params: release Geth 1.8.2 stable

github: config for probot-stale bot (#16235 )
* github: config for probot-stale bot * github: use stale label, instead of wontfix
2018-03-05 15:48:48 +02:00 · 2018-03-05 15:23:26 +02:00 · 2018-03-05 14:33:45 +02:00 · 2018-03-05 14:23:48 +02:00 · 2018-03-05 14:01:13 +02:00 · 2018-03-05 13:02:32 +02:00
2868 changed files with 474431 additions and 2603556 deletions
--- a/.dockerignore
+++ b/.dockerignore
@@ -0,0 +1,9 @@
+**/.git
+.git
+!.git/HEAD
+!.git/refs/heads
+**/*_test.go
+
+build/_workspace
+build/_bin
+tests/testdata
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -0,0 +1,11 @@
+# Lines starting with '#' are comments.
+# Each line is a file pattern followed by one or more owners.
+
+accounts/usbwallet @karalabe
+consensus          @karalabe
+core/              @karalabe @holiman
+eth/               @karalabe
+les/               @zsfelfoldi
+light/             @zsfelfoldi
+mobile/            @karalabe
+p2p/               @fjl @zsfelfoldi
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -2,16 +2,14 @@

 Before you do a feature request please check and make sure that it isn't possible
 through some other means. The JavaScript enabled console is a powerful feature
-in the right hands. Please check our [Bitchin' tricks](https://github.com/ethereum/go-ethereum/wiki/bitchin-tricks) wiki page for more info
+in the right hands. Please check our [Wiki page](https://github.com/ethereum/go-ethereum/wiki) for more info
 and help.

 ## Contributing

 If you'd like to contribute to go-ethereum please fork, fix, commit and
 send a pull request. Commits which do not comply with the coding standards
-are ignored (use gofmt!). If you send pull requests make absolute sure that you
-commit on the `develop` branch and that you do not merge to master.
-Commits that are directly based on master are simply ignored.
+are ignored (use gofmt!).

 See [Developers' Guide](https://github.com/ethereum/go-ethereum/wiki/Developers'-Guide)
 for more details on configuring your environment, testing, and
--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -1,3 +1,9 @@
+Hi there,
+
+please note that this is an issue tracker reserved for bug reports and feature requests.
+
+For general questions please use the gitter channel or the Ethereum stack exchange at https://ethereum.stackexchange.com.
+
 #### System information

 Geth version: `geth version`
--- a/.github/stale.yml
+++ b/.github/stale.yml
@@ -0,0 +1,17 @@
+# Number of days of inactivity before an issue becomes stale
+daysUntilStale: 366
+# Number of days of inactivity before a stale issue is closed
+daysUntilClose: 42
+# Issues with these labels will never be considered stale
+exemptLabels:
+  - pinned
+  - security
+# Label to use when marking an issue as stale
+staleLabel: stale
+# Comment to post when marking an issue as stale. Set to `false` to disable
+markComment: >
+  This issue has been automatically marked as stale because it has not had
+  recent activity. It will be closed if no further activity occurs. Thank you
+  for your contributions.
+# Comment to post when closing a stale issue. Set to `false` to disable
+closeComment: false
--- a/.gitignore
+++ b/.gitignore
@@ -30,3 +30,15 @@ build/_vendor/pkg
 # travis
 profile.tmp
 profile.cov
+
+# IdeaIDE
+.idea
+
+# VS Code
+.vscode
+
+# dashboard
+/dashboard/assets/flow-typed
+/dashboard/assets/node_modules
+/dashboard/assets/stats.json
+/dashboard/assets/bundle.js
--- a/.gitmodules
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "tests"]
+	path = tests/testdata
+	url = https://github.com/ethereum/tests
--- a/.mailmap
+++ b/.mailmap
@@ -65,11 +65,12 @@ Enrique Fynn <enriquefynn@gmail.com>

 Vincent G <caktux@gmail.com>

-RJ Catalano <rj@erisindustries.com>
+RJ Catalano <catalanor0220@gmail.com>
+RJ Catalano <catalanor0220@gmail.com> <rj@erisindustries.com>

 Nchinda Nchinda <nchinda2@gmail.com>

-Aron Fischer <homotopycolimit@users.noreply.github.com>
+Aron Fischer <github@aron.guru> <homotopycolimit@users.noreply.github.com>

 Vlad Gluhovsky <gluk256@users.noreply.github.com>

@@ -90,3 +91,33 @@ Nick Johnson <arachnid@notdot.net>
 Henning Diedrich <hd@eonblast.com>
 Henning Diedrich <hd@eonblast.com> Drake Burroughs <wildfyre@hotmail.com>

+Felix Lange <fjl@twurst.com>
+Felix Lange <fjl@twurst.com> <fjl@users.noreply.github.com>
+
+Максим Чусовлянов <mchusovlianov@gmail.com>
+
+Louis Holbrook <dev@holbrook.no>
+Louis Holbrook <dev@holbrook.no> <nolash@users.noreply.github.com>
+
+Thomas Bocek <tom@tomp2p.net>
+
+Victor Tran <vu.tran54@gmail.com>
+
+Justin Drake <drakefjustin@gmail.com>
+
+Frank Wang <eternnoir@gmail.com>
+
+Gary Rong <garyrong0905@gmail.com>
+
+Guillaume Nicolas <guin56@gmail.com>
+
+Sorin Neacsu <sorin.neacsu@gmail.com>
+Sorin Neacsu <sorin.neacsu@gmail.com> <sorin@users.noreply.github.com>
+
+Valentin Wüstholz <wuestholz@gmail.com>
+Valentin Wüstholz <wuestholz@gmail.com> <wuestholz@users.noreply.github.com>
+
+Armin Braun <me@obrown.io>
+
+Ernesto del Toro <ernesto.deltoro@gmail.com>
+Ernesto del Toro <ernesto.deltoro@gmail.com> <ernestodeltoro@users.noreply.github.com>
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,26 +5,58 @@ matrix:
  include:
    - os: linux
      dist: trusty
-      go: 1.5.4
-      env:
-        - GO15VENDOREXPERIMENT=1
+      sudo: required
+      go: 1.8.x
+      script:
+        - sudo modprobe fuse
+        - sudo chmod 666 /dev/fuse
+        - sudo chown root:$USER /etc/fuse.conf
+        - go run build/ci.go install
+        - go run build/ci.go test -coverage
+
+    # These are the latest Go versions.
    - os: linux
      dist: trusty
-      go: 1.6.2
-    - os: linux
-      dist: trusty
-      go: 1.7
+      sudo: required
+      go: 1.9.x
+      script:
+        - sudo modprobe fuse
+        - sudo chmod 666 /dev/fuse
+        - sudo chown root:$USER /etc/fuse.conf
+        - go run build/ci.go install
+        - go run build/ci.go test -coverage
+
    - os: osx
-      go: 1.7
+      go: 1.9.x
+      script:
+        - unset -f cd # workaround for https://github.com/travis-ci/travis-ci/issues/8703
+        - brew update
+        - brew install caskroom/cask/brew-cask
+        - brew cask install osxfuse
+        - go run build/ci.go install
+        - go run build/ci.go test -coverage
+
+    # This builder only tests code linters on latest version of Go
+    - os: linux
+      dist: trusty
+      go: 1.9.x
+      env:
+        - lint
+      git:
+        submodules: false # avoid cloning ethereum/tests
+      script:
+        - go run build/ci.go lint

    # This builder does the Ubuntu PPA and Linux Azure uploads
    - os: linux
      dist: trusty
      sudo: required
-      go: 1.7
+      go: 1.9.x
      env:
        - ubuntu-ppa
        - azure-linux
+      git:
+        submodules: false # avoid cloning ethereum/tests
      addons:
        apt:
          packages:
@@ -32,6 +64,7 @@ matrix:
            - debhelper
            - dput
            - gcc-multilib
+            - fakeroot
      script:
        # Build for the primary platforms that Trusty can manage
        - go run build/ci.go debsrc -signer "Go Ethereum Linux Builder <geth-ci@ethereum.org>" -upload ppa:ethereum/ethereum
@@ -44,54 +77,118 @@ matrix:
        - sudo -E apt-get -yq --no-install-suggests --no-install-recommends --force-yes install gcc-arm-linux-gnueabi libc6-dev-armel-cross gcc-arm-linux-gnueabihf libc6-dev-armhf-cross gcc-aarch64-linux-gnu libc6-dev-arm64-cross
        - sudo ln -s /usr/include/asm-generic /usr/include/asm

-        - GOARM=5 CC=arm-linux-gnueabi-gcc go run build/ci.go install -arch arm
+        - GOARM=5 go run build/ci.go install -arch arm -cc arm-linux-gnueabi-gcc
        - GOARM=5 go run build/ci.go archive -arch arm -type tar -signer LINUX_SIGNING_KEY -upload gethstore/builds
-        - GOARM=6 CC=arm-linux-gnueabi-gcc go run build/ci.go install -arch arm
+        - GOARM=6 go run build/ci.go install -arch arm -cc arm-linux-gnueabi-gcc
        - GOARM=6 go run build/ci.go archive -arch arm -type tar -signer LINUX_SIGNING_KEY -upload gethstore/builds
-        - GOARM=7 CC=arm-linux-gnueabihf-gcc go run build/ci.go install -arch arm
+        - GOARM=7 go run build/ci.go install -arch arm -cc arm-linux-gnueabihf-gcc
        - GOARM=7 go run build/ci.go archive -arch arm -type tar -signer LINUX_SIGNING_KEY -upload gethstore/builds
-        - CC=aarch64-linux-gnu-gcc go run build/ci.go install -arch arm64
+        - go run build/ci.go install -arch arm64 -cc aarch64-linux-gnu-gcc
        - go run build/ci.go archive -arch arm64 -type tar -signer LINUX_SIGNING_KEY -upload gethstore/builds

-    # This builder does the OSX Azure, Android Maven and Azure and iOS CocoaPods and Azure uploads
+    # This builder does the Linux Azure MIPS xgo uploads
+    - os: linux
+      dist: trusty
+      services:
+        - docker
+      go: 1.9.x
+      env:
+        - azure-linux-mips
+      git:
+        submodules: false # avoid cloning ethereum/tests
+      script:
+        - go run build/ci.go xgo --alltools -- --targets=linux/mips --ldflags '-extldflags "-static"' -v
+        - for bin in build/bin/*-linux-mips; do mv -f "${bin}" "${bin/-linux-mips/}"; done
+        - go run build/ci.go archive -arch mips -type tar -signer LINUX_SIGNING_KEY -upload gethstore/builds
+
+        - go run build/ci.go xgo --alltools -- --targets=linux/mipsle --ldflags '-extldflags "-static"' -v
+        - for bin in build/bin/*-linux-mipsle; do mv -f "${bin}" "${bin/-linux-mipsle/}"; done
+        - go run build/ci.go archive -arch mipsle -type tar -signer LINUX_SIGNING_KEY -upload gethstore/builds
+
+        - go run build/ci.go xgo --alltools -- --targets=linux/mips64 --ldflags '-extldflags "-static"' -v
+        - for bin in build/bin/*-linux-mips64; do mv -f "${bin}" "${bin/-linux-mips64/}"; done
+        - go run build/ci.go archive -arch mips64 -type tar -signer LINUX_SIGNING_KEY -upload gethstore/builds
+
+        - go run build/ci.go xgo --alltools -- --targets=linux/mips64le --ldflags '-extldflags "-static"' -v
+        - for bin in build/bin/*-linux-mips64le; do mv -f "${bin}" "${bin/-linux-mips64le/}"; done
+        - go run build/ci.go archive -arch mips64le -type tar -signer LINUX_SIGNING_KEY -upload gethstore/builds
+
+    # This builder does the Android Maven and Azure uploads
+    - os: linux
+      dist: precise # Needed for the android tools
+      addons:
+        apt:
+          packages:
+            - oracle-java8-installer
+            - oracle-java8-set-default
+      language: android
+      android:
+        components:
+          - platform-tools
+          - tools
+          - android-15
+          - android-19
+          - android-24
+      env:
+        - azure-android
+        - maven-android
+      git:
+        submodules: false # avoid cloning ethereum/tests
+      before_install:
+        - curl https://storage.googleapis.com/golang/go1.9.2.linux-amd64.tar.gz | tar -xz
+        - export PATH=`pwd`/go/bin:$PATH
+        - export GOROOT=`pwd`/go
+        - export GOPATH=$HOME/go
+      script:
+        # Build the Android archive and upload it to Maven Central and Azure
+        - curl https://dl.google.com/android/repository/android-ndk-r15c-linux-x86_64.zip -o android-ndk-r15c.zip
+        - unzip -q android-ndk-r15c.zip && rm android-ndk-r15c.zip
+        - mv android-ndk-r15c $HOME
+        - export ANDROID_NDK=$HOME/android-ndk-r15c
+
+        - mkdir -p $GOPATH/src/github.com/ethereum
+        - ln -s `pwd` $GOPATH/src/github.com/ethereum
+        - go run build/ci.go aar -signer ANDROID_SIGNING_KEY -deploy https://oss.sonatype.org -upload gethstore/builds
+
+    # This builder does the OSX Azure, iOS CocoaPods and iOS Azure uploads
    - os: osx
-      go: 1.7
+      go: 1.9.x
      env:
        - azure-osx
-        - mobile
-      cache:
-        directories:
-          - $HOME/.android.platforms
-          - $HOME/.cocoapods
+        - azure-ios
+        - cocoapods-ios
+      git:
+        submodules: false # avoid cloning ethereum/tests
      script:
        - go run build/ci.go install
        - go run build/ci.go archive -type tar -signer OSX_SIGNING_KEY -upload gethstore/builds

-        # Build the Android archive and upload it to Maven Central and Azure
-        - brew update
-        - brew install android-sdk maven gpg
-        - alias gpg="gpg2"
-        - export ANDROID_HOME=/usr/local/opt/android-sdk
-
-        - mkdir -p $ANDROID_HOME/platforms
-        - mv -f $HOME/.android.platforms $ANDROID_HOME/platforms
-        - echo "y" | android update sdk --no-ui --filter platform
-
-        - go run build/ci.go aar -signer ANDROID_SIGNING_KEY -deploy https://oss.sonatype.org -upload gethstore/builds
-        - mv -f $ANDROID_HOME/platforms $HOME/.android.platforms
-
        # Build the iOS framework and upload it to CocoaPods and Azure
-        - gem uninstall cocoapods -a
-        - gem install cocoapods --pre
+        - gem uninstall cocoapods -a -x
+        - gem install cocoapods
+
+        - mv ~/.cocoapods/repos/master ~/.cocoapods/repos/master.bak
+        - sed -i '.bak' 's/repo.join/!repo.join/g' $(dirname `gem which cocoapods`)/cocoapods/sources_manager.rb
+        - if [ "$TRAVIS_PULL_REQUEST" = "false" ]; then git clone --depth=1 https://github.com/CocoaPods/Specs.git ~/.cocoapods/repos/master && pod setup --verbose; fi
+
        - xctool -version
        - xcrun simctl list
-        - travis_wait 30 go run build/ci.go xcode -signer IOS_SIGNING_KEY -deploy trunk -upload gethstore/builds

-install:
-  - go get golang.org/x/tools/cmd/cover
-script:
-  - go run build/ci.go install
-  - go run build/ci.go test -coverage -vet
+        # Workaround for https://github.com/golang/go/issues/23749
+        - export CGO_CFLAGS_ALLOW='-fmodules|-fblocks|-fobjc-arc'
+        - go run build/ci.go xcode -signer IOS_SIGNING_KEY -deploy trunk -upload gethstore/builds
+
+    # This builder does the Azure archive purges to avoid accumulating junk
+    - os: linux
+      dist: trusty
+      sudo: required
+      go: 1.9.x
+      env:
+        - azure-purge
+      git:
+        submodules: false # avoid cloning ethereum/tests
+      script:
+        - go run build/ci.go purge -store gethstore/builds -days 14

 notifications:
  webhooks:
--- a/114
+++ b/114
@@ -1,63 +1,173 @@
 # This is the official list of go-ethereum authors for copyright purposes.

+Afri Schoedon <5chdn@users.noreply.github.com>
+Agustin Armellini Fischer <armellini13@gmail.com>
+Airead <fgh1987168@gmail.com>
+Alan Chen <alanchchen@users.noreply.github.com>
+Alejandro Isaza <alejandro.isaza@gmail.com>
 Ales Katona <ales@coinbase.com>
 Alex Leverington <alex@ethdev.com>
+Alex Wu <wuyiding@gmail.com>
 Alexandre Van de Sande <alex.vandesande@ethdev.com>
-Aron Fischer <homotopycolimit@users.noreply.github.com>
+Ali Hajimirza <Ali92hm@users.noreply.github.com>
+Anton Evangelatov <anton.evangelatov@gmail.com>
+Arba Sasmoyo <arba.sasmoyo@gmail.com>
+Armani Ferrante <armaniferrante@berkeley.edu>
+Armin Braun <me@obrown.io>
+Aron Fischer <github@aron.guru>
 Bas van Kervel <bas@ethdev.com>
 Benjamin Brent <benjamin@benjaminbrent.com>
+Benoit Verkindt <benoit.verkindt@gmail.com>
+Bo <bohende@gmail.com>
+Bo Ye <boy.e.computer.1982@outlook.com>
+Bob Glickstein <bobg@users.noreply.github.com>
+Brian Schroeder <bts@gmail.com>
 Casey Detrio <cdetrio@gmail.com>
+Chase Wright <mysticryuujin@gmail.com>
 Christoph Jentzsch <jentzsch.software@gmail.com>
 Daniel A. Nagy <nagy.da@gmail.com>
+Daniel Sloof <goapsychadelic@gmail.com>
+Darrel Herbst <dherbst@gmail.com>
+Dave Appleton <calistralabs@gmail.com>
+Diego Siqueira <DiSiqueira@users.noreply.github.com>
+Dmitry Shulyak <yashulyak@gmail.com>
+Egon Elbre <egonelbre@gmail.com>
+Elias Naur <elias.naur@gmail.com>
 Elliot Shepherd <elliot@identitii.com>
 Enrique Fynn <enriquefynn@gmail.com>
+Ernesto del Toro <ernesto.deltoro@gmail.com>
 Ethan Buchman <ethan@coinculture.info>
+Eugene Valeyev <evgen.povt@gmail.com>
+Evangelos Pappas <epappas@evalonlabs.com>
+Evgeny Danilenko <6655321@bk.ru>
 Fabian Vogelsteller <fabian@frozeman.de>
+Fabio Barone <fabio.barone.co@gmail.com>
 Fabio Berger <fabioberger1991@gmail.com>
+FaceHo <facehoshi@gmail.com>
 Felix Lange <fjl@twurst.com>
+Fiisio <liangcszzu@163.com>
+Frank Wang <eternnoir@gmail.com>
+Furkan KAMACI <furkankamaci@gmail.com>
+Gary Rong <garyrong0905@gmail.com>
+George Ornbo <george@shapeshed.com>
 Gregg Dourgarian <greggd@tempworks.com>
+Guillaume Ballet <gballet@gmail.com>
+Guillaume Nicolas <guin56@gmail.com>
 Gustav Simonsson <gustav.simonsson@gmail.com>
 Hao Bryan Cheng <haobcheng@gmail.com>
 Henning Diedrich <hd@eonblast.com>
 Isidoro Ghezzi <isidoro.ghezzi@icloud.com>
+Ivan Daniluk <ivan.daniluk@gmail.com>
 Jae Kwon <jkwon.work@gmail.com>
+Jamie Pitts <james.pitts@gmail.com>
+Janoš Guljaš <janos@users.noreply.github.com>
 Jason Carver <jacarver@linkedin.com>
+Jay Guo <guojiannan1101@gmail.com>
 Jeff R. Allen <jra@nella.org>
 Jeffrey Wilcke <jeffrey@ethereum.org>
 Jens Agerberg <github@agerberg.me>
+Jia Chenhui <jiachenhui1989@gmail.com>
+Jim McDonald <Jim@mcdee.net>
+Joel Burget <joelburget@gmail.com>
 Jonathan Brown <jbrown@bluedroplet.com>
 Joseph Chow <ethereum@outlook.com>
 Justin Clark-Casey <justincc@justincc.org>
+Justin Drake <drakefjustin@gmail.com>
 Kenji Siu <kenji@isuntv.com>
 Kobi Gurkan <kobigurk@gmail.com>
+Konrad Feldmeier <konrad@brainbot.com>
+Kurkó Mihály <kurkomisi@users.noreply.github.com>
+Kyuntae Ethan Kim <ethan.kyuntae.kim@gmail.com>
 Lefteris Karapetsas <lefteris@refu.co>
 Leif Jurvetson <leijurv@gmail.com>
+Leo Shklovskii <leo@thermopylae.net>
+Lewis Marshall <lewis@lmars.net>
+Lio李欧 <lionello@users.noreply.github.com>
+Louis Holbrook <dev@holbrook.no>
+Luca Zeug <luclu@users.noreply.github.com>
+Magicking <s@6120.eu>
 Maran Hidskes <maran.hidskes@gmail.com>
 Marek Kotewicz <marek.kotewicz@gmail.com>
+Mark <markya0616@gmail.com>
 Martin Holst Swende <martin@swende.se>
 Matthew Di Ferrante <mattdf@users.noreply.github.com>
 Matthew Wampler-Doty <matthew.wampler.doty@gmail.com>
+Maximilian Meister <mmeister@suse.de>
+Micah Zoltu <micah@zoltu.net>
+Michael Ruminer <michael.ruminer+github@gmail.com>
+Miguel Mota <miguelmota2@gmail.com>
+Miya Chen <miyatlchen@gmail.com>
 Nchinda Nchinda <nchinda2@gmail.com>
 Nick Dodson <silentcicero@outlook.com>
 Nick Johnson <arachnid@notdot.net>
+Nicolas Guillaume <gunicolas@sqli.com>
+Noman <noman@noman.land>
+Oli Bye <olibye@users.noreply.github.com>
+Paul Litvak <litvakpol@012.net.il>
 Paulo L F Casaretto <pcasaretto@gmail.com>
+Paweł Bylica <chfast@gmail.com>
 Peter Pratscher <pratscher@gmail.com>
+Petr Mikusek <petr@mikusek.info>
 Péter Szilágyi <peterke@gmail.com>
-RJ Catalano <rj@erisindustries.com>
+RJ Catalano <catalanor0220@gmail.com>
 Ramesh Nair <ram@hiddentao.com>
 Ricardo Catalinas Jiménez <r@untroubled.be>
+Ricardo Domingos <ricardohsd@gmail.com>
+Richard Hart <richardhart92@gmail.com>
+Rob <robert@rojotek.com>
+Robert Zaremba <robert.zaremba@scale-it.pl>
+Russ Cox <rsc@golang.org>
 Rémy Roy <remyroy@remyroy.com>
+S. Matthew English <s-matthew-english@users.noreply.github.com>
+Shintaro Kaneko <kaneshin0120@gmail.com>
+Sorin Neacsu <sorin.neacsu@gmail.com>
 Stein Dekker <dekker.stein@gmail.com>
+Steve Waldman <swaldman@mchange.com>
 Steven Roose <stevenroose@gmail.com>
 Taylor Gerring <taylor.gerring@gmail.com>
 Thomas Bocek <tom@tomp2p.net>
+Ti Zhou <tizhou1986@gmail.com>
 Tosh Camille <tochecamille@gmail.com>
+Valentin Wüstholz <wuestholz@gmail.com>
+Victor Farazdagi <simple.square@gmail.com>
+Victor Tran <vu.tran54@gmail.com>
 Viktor Trón <viktor.tron@gmail.com>
 Ville Sundell <github@solarius.fi>
 Vincent G <caktux@gmail.com>
 Vitalik Buterin <v@buterin.com>
+Vitaly V <vvelikodny@gmail.com>
+Vivek Anand <vivekanand1101@users.noreply.github.com>
 Vlad Gluhovsky <gluk256@users.noreply.github.com>
 Yohann Léon <sybiload@gmail.com>
 Yoichi Hirai <i@yoichihirai.com>
+Yondon Fu <yondon.fu@gmail.com>
+Zach <zach.ramsay@gmail.com>
+Zahoor Mohamed <zahoor@zahoor.in>
+Zoe Nolan <github@zoenolan.org>
 Zsolt Felföldi <zsfelfoldi@gmail.com>
+am2rican5 <am2rican5@gmail.com>
+ayeowch <ayeowch@gmail.com>
+b00ris <b00ris@mail.ru>
+bailantaotao <Edwin@maicoin.com>
+baizhenxuan <nkbai@163.com>
+bloonfield <bloonfield@163.com>
+changhong <changhong.yu@shanbay.com>
+evgk <evgeniy.kamyshev@gmail.com>
+ferhat elmas <elmas.ferhat@gmail.com>
+holisticode <holistic.computing@gmail.com>
+jtakalai <juuso.takalainen@streamr.com>
+ken10100147 <sunhongping@kanjian.com>
+ligi <ligi@ligi.de>
+mark.lin <mark@maicoin.com>
+necaremus <necaremus@gmail.com>
+njupt-moon <1015041018@njupt.edu.cn>
+nkbai <nkbai@163.com>
+rhaps107 <dod-source@yandex.ru>
+slumber1122 <slumber1122@gmail.com>
+sunxiaojun2014 <sunxiaojun-xy@360.cn>
+terasum <terasum@163.com>
+tsarpaul <Litvakpol@012.net.il>
+xiekeyang <xiekeyang@users.noreply.github.com>
+yoza <yoza.is12s@gmail.com>
 ΞTHΞЯSPHΞЯΞ <{viktor.tron,nagydani,zsfelfoldi}@gmail.com>
+Максим Чусовлянов <mchusovlianov@gmail.com>
--- a/16
+++ b/16
@@ -0,0 +1,16 @@
+# Build Geth in a stock Go builder container
+FROM golang:1.9-alpine as builder
+
+RUN apk add --no-cache make gcc musl-dev linux-headers
+
+ADD . /go-ethereum
+RUN cd /go-ethereum && make geth
+
+# Pull Geth into a second stage deploy alpine container
+FROM alpine:latest
+
+RUN apk add --no-cache ca-certificates
+COPY --from=builder /go-ethereum/build/bin/geth /usr/local/bin/
+
+EXPOSE 8545 8546 30303 30303/udp 30304/udp
+ENTRYPOINT ["geth"]
--- a/Dockerfile.alltools
+++ b/Dockerfile.alltools
@@ -0,0 +1,15 @@
+# Build Geth in a stock Go builder container
+FROM golang:1.9-alpine as builder
+
+RUN apk add --no-cache make gcc musl-dev linux-headers
+
+ADD . /go-ethereum
+RUN cd /go-ethereum && make all
+
+# Pull all binaries into a second stage deploy alpine container
+FROM alpine:latest
+
+RUN apk add --no-cache ca-certificates
+COPY --from=builder /go-ethereum/build/bin/* /usr/local/bin/
+
+EXPOSE 8545 8546 30303 30303/udp 30304/udp
--- a/78
+++ b/78
@@ -2,14 +2,13 @@
 # with Go source code. If you know what GOPATH is then you probably
 # don't need to bother with make.

-.PHONY: geth geth-cross evm all test clean
+.PHONY: geth android ios geth-cross swarm evm all test clean
 .PHONY: geth-linux geth-linux-386 geth-linux-amd64 geth-linux-mips64 geth-linux-mips64le
 .PHONY: geth-linux-arm geth-linux-arm-5 geth-linux-arm-6 geth-linux-arm-7 geth-linux-arm64
 .PHONY: geth-darwin geth-darwin-386 geth-darwin-amd64
 .PHONY: geth-windows geth-windows-386 geth-windows-amd64
-.PHONY: geth-android geth-ios

-GOBIN = build/bin
+GOBIN = $(shell pwd)/build/bin
 GO ?= latest

 geth:
@@ -17,20 +16,43 @@ geth:
 	@echo "Done building."
 	@echo "Run \"$(GOBIN)/geth\" to launch geth."

-evm:
-	build/env.sh go run build/ci.go install ./cmd/evm
+swarm:
+	build/env.sh go run build/ci.go install ./cmd/swarm
 	@echo "Done building."
-	@echo "Run \"$(GOBIN)/evm to start the evm."
+	@echo "Run \"$(GOBIN)/swarm\" to launch swarm."

 all:
 	build/env.sh go run build/ci.go install

+android:
+	build/env.sh go run build/ci.go aar --local
+	@echo "Done building."
+	@echo "Import \"$(GOBIN)/geth.aar\" to use the library."
+
+ios:
+	build/env.sh go run build/ci.go xcode --local
+	@echo "Done building."
+	@echo "Import \"$(GOBIN)/Geth.framework\" to use the library."
+
 test: all
 	build/env.sh go run build/ci.go test

 clean:
 	rm -fr build/_workspace/pkg/ $(GOBIN)/*

+# The devtools target installs tools required for 'go generate'.
+# You need to put $GOBIN (or $GOPATH/bin) in your PATH to use 'go generate'.
+
+devtools:
+	env GOBIN= go get -u golang.org/x/tools/cmd/stringer
+	env GOBIN= go get -u github.com/kevinburke/go-bindata/go-bindata
+	env GOBIN= go get -u github.com/fjl/gencodec
+	env GOBIN= go get -u github.com/golang/protobuf/protoc-gen-go
+	env GOBIN= go install ./cmd/abigen
+	@type "npm" 2> /dev/null || echo 'Please install node.js and npm'
+	@type "solc" 2> /dev/null || echo 'Please install solc'
+	@type "protoc" 2> /dev/null || echo 'Please install protoc'
+
 # Cross Compilation Targets (xgo)

 geth-cross: geth-linux geth-darwin geth-windows geth-android geth-ios
@@ -42,12 +64,12 @@ geth-linux: geth-linux-386 geth-linux-amd64 geth-linux-arm geth-linux-mips64 get
 	@ls -ld $(GOBIN)/geth-linux-*

 geth-linux-386:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=linux/386 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/386 -v ./cmd/geth
 	@echo "Linux 386 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-linux-* | grep 386

 geth-linux-amd64:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=linux/amd64 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/amd64 -v ./cmd/geth
 	@echo "Linux amd64 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-linux-* | grep amd64

@@ -56,32 +78,42 @@ geth-linux-arm: geth-linux-arm-5 geth-linux-arm-6 geth-linux-arm-7 geth-linux-ar
 	@ls -ld $(GOBIN)/geth-linux-* | grep arm

 geth-linux-arm-5:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=linux/arm-5 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/arm-5 -v ./cmd/geth
 	@echo "Linux ARMv5 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-linux-* | grep arm-5

 geth-linux-arm-6:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=linux/arm-6 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/arm-6 -v ./cmd/geth
 	@echo "Linux ARMv6 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-linux-* | grep arm-6

 geth-linux-arm-7:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=linux/arm-7 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/arm-7 -v ./cmd/geth
 	@echo "Linux ARMv7 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-linux-* | grep arm-7

 geth-linux-arm64:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=linux/arm64 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/arm64 -v ./cmd/geth
 	@echo "Linux ARM64 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-linux-* | grep arm64

+geth-linux-mips:
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/mips --ldflags '-extldflags "-static"' -v ./cmd/geth
+	@echo "Linux MIPS cross compilation done:"
+	@ls -ld $(GOBIN)/geth-linux-* | grep mips
+
+geth-linux-mipsle:
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/mipsle --ldflags '-extldflags "-static"' -v ./cmd/geth
+	@echo "Linux MIPSle cross compilation done:"
+	@ls -ld $(GOBIN)/geth-linux-* | grep mipsle
+
 geth-linux-mips64:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=linux/mips64 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/mips64 --ldflags '-extldflags "-static"' -v ./cmd/geth
 	@echo "Linux MIPS64 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-linux-* | grep mips64

 geth-linux-mips64le:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=linux/mips64le -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=linux/mips64le --ldflags '-extldflags "-static"' -v ./cmd/geth
 	@echo "Linux MIPS64le cross compilation done:"
 	@ls -ld $(GOBIN)/geth-linux-* | grep mips64le

@@ -90,12 +122,12 @@ geth-darwin: geth-darwin-386 geth-darwin-amd64
 	@ls -ld $(GOBIN)/geth-darwin-*

 geth-darwin-386:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=darwin/386 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=darwin/386 -v ./cmd/geth
 	@echo "Darwin 386 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-darwin-* | grep 386

 geth-darwin-amd64:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=darwin/amd64 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=darwin/amd64 -v ./cmd/geth
 	@echo "Darwin amd64 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-darwin-* | grep amd64

@@ -104,21 +136,11 @@ geth-windows: geth-windows-386 geth-windows-amd64
 	@ls -ld $(GOBIN)/geth-windows-*

 geth-windows-386:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=windows/386 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=windows/386 -v ./cmd/geth
 	@echo "Windows 386 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-windows-* | grep 386

 geth-windows-amd64:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=windows/amd64 -v ./cmd/geth
+	build/env.sh go run build/ci.go xgo -- --go=$(GO) --targets=windows/amd64 -v ./cmd/geth
 	@echo "Windows amd64 cross compilation done:"
 	@ls -ld $(GOBIN)/geth-windows-* | grep amd64
-
-geth-android:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=android-21/aar -v ./cmd/geth
-	@echo "Android cross compilation done:"
-	@ls -ld $(GOBIN)/geth-android-*
-
-geth-ios:
-	build/env.sh go run build/ci.go xgo -- --go=$(GO) --dest=$(GOBIN) --targets=ios-7.0/framework -v ./cmd/geth
-	@echo "iOS framework cross compilation done:"
-	@ls -ld $(GOBIN)/geth-ios-*
--- a/README.md
+++ b/README.md
@@ -1,28 +1,16 @@
-## Ethereum Go
+## Go Ethereum

-Official golang implementation of the Ethereum protocol
-
-          | Linux   | OSX | ARM | Windows | Tests
----------|---------|-----|-----|---------|------
-develop   | [![Build+Status](https://build.ethdev.com/buildstatusimage?builder=Linux%20Go%20develop%20branch)](https://build.ethdev.com/builders/Linux%20Go%20develop%20branch/builds/-1) | [![Build+Status](https://build.ethdev.com/buildstatusimage?builder=Linux%20Go%20develop%20branch)](https://build.ethdev.com/builders/OSX%20Go%20develop%20branch/builds/-1) | [![Build+Status](https://build.ethdev.com/buildstatusimage?builder=ARM%20Go%20develop%20branch)](https://build.ethdev.com/builders/ARM%20Go%20develop%20branch/builds/-1) | [![Build+Status](https://build.ethdev.com/buildstatusimage?builder=Windows%20Go%20develop%20branch)](https://build.ethdev.com/builders/Windows%20Go%20develop%20branch/builds/-1) | [![Buildr+Status](https://travis-ci.org/ethereum/go-ethereum.svg?branch=develop)](https://travis-ci.org/ethereum/go-ethereum) [![codecov.io](https://codecov.io/github/ethereum/go-ethereum/coverage.svg?branch=develop)](https://codecov.io/github/ethereum/go-ethereum?branch=develop)
-master    | [![Build+Status](https://build.ethdev.com/buildstatusimage?builder=Linux%20Go%20master%20branch)](https://build.ethdev.com/builders/Linux%20Go%20master%20branch/builds/-1) | [![Build+Status](https://build.ethdev.com/buildstatusimage?builder=OSX%20Go%20master%20branch)](https://build.ethdev.com/builders/OSX%20Go%20master%20branch/builds/-1) | [![Build+Status](https://build.ethdev.com/buildstatusimage?builder=ARM%20Go%20master%20branch)](https://build.ethdev.com/builders/ARM%20Go%20master%20branch/builds/-1) | [![Build+Status](https://build.ethdev.com/buildstatusimage?builder=Windows%20Go%20master%20branch)](https://build.ethdev.com/builders/Windows%20Go%20master%20branch/builds/-1) | [![Buildr+Status](https://travis-ci.org/ethereum/go-ethereum.svg?branch=master)](https://travis-ci.org/ethereum/go-ethereum) [![codecov.io](https://codecov.io/github/ethereum/go-ethereum/coverage.svg?branch=master)](https://codecov.io/github/ethereum/go-ethereum?branch=master)
+Official golang implementation of the Ethereum protocol.

 [![API Reference](
 https://camo.githubusercontent.com/915b7be44ada53c290eb157634330494ebe3e30a/68747470733a2f2f676f646f632e6f72672f6769746875622e636f6d2f676f6c616e672f6764646f3f7374617475732e737667
 )](https://godoc.org/github.com/ethereum/go-ethereum)
+[![Go Report Card](https://goreportcard.com/badge/github.com/ethereum/go-ethereum)](https://goreportcard.com/report/github.com/ethereum/go-ethereum)
+[![Travis](https://travis-ci.org/ethereum/go-ethereum.svg?branch=master)](https://travis-ci.org/ethereum/go-ethereum)
 [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/ethereum/go-ethereum?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)

-## Automated development builds
-
-The following builds are built automatically by our build servers after each push to the [develop](https://github.com/ethereum/go-ethereum/tree/develop) branch.
-
-* [Docker](https://registry.hub.docker.com/u/ethereum/client-go/)
-* [OS X](https://build.ethdev.com/builds/OSX%20Go%20develop%20branch/Mist-OSX-latest.dmg)
-* Ubuntu
-  [trusty](https://build.ethdev.com/builds/Linux%20Go%20develop%20deb%20i386-trusty/latest/) |
-  [utopic](https://build.ethdev.com/builds/Linux%20Go%20develop%20deb%20i386-utopic/latest/)
-* [Windows 64-bit](https://build.ethdev.com/builds/Windows%20Go%20develop%20branch/Geth-Win64-latest.zip)
-* [ARM](https://build.ethdev.com/builds/ARM%20Go%20develop%20branch/geth-ARM-latest.tar.bz2)
+Automated builds are available for stable releases and the unstable master branch.
+Binary archives are published at https://geth.ethereum.org/downloads/.

 ## Building the source

@@ -30,7 +18,7 @@ For prerequisites and detailed build instructions please read the
 [Installation Instructions](https://github.com/ethereum/go-ethereum/wiki/Building-Ethereum)
 on the wiki.

-Building geth requires both a Go and a C compiler.
+Building geth requires both a Go (version 1.7 or later) and a C compiler.
 You can install them using your favourite package manager.
 Once the dependencies are installed, run

@@ -46,13 +34,14 @@ The go-ethereum project comes with several wrappers/executables found in the `cm

 | Command    | Description |
 |:----------:|-------------|
-| **`geth`** | Our main Ethereum CLI client. It is the entry point into the Ethereum network (main-, test- or private net), capable of running as a full node (default) archive node (retaining all historical state) or a light node (retrieving data live). It can be used by other processes as a gateway into the Ethereum network via JSON RPC endpoints exposed on top of HTTP, WebSocket and/or IPC transports. Please see our [Command Line Options](https://github.com/ethereum/go-ethereum/wiki/Command-Line-Options) wiki page for details. |
+| **`geth`** | Our main Ethereum CLI client. It is the entry point into the Ethereum network (main-, test- or private net), capable of running as a full node (default) archive node (retaining all historical state) or a light node (retrieving data live). It can be used by other processes as a gateway into the Ethereum network via JSON RPC endpoints exposed on top of HTTP, WebSocket and/or IPC transports. `geth --help` and the [CLI Wiki page](https://github.com/ethereum/go-ethereum/wiki/Command-Line-Options) for command line options. |
 | `abigen` | Source code generator to convert Ethereum contract definitions into easy to use, compile-time type-safe Go packages. It operates on plain [Ethereum contract ABIs](https://github.com/ethereum/wiki/wiki/Ethereum-Contract-ABI) with expanded functionality if the contract bytecode is also available. However it also accepts Solidity source files, making development much more streamlined. Please see our [Native DApps](https://github.com/ethereum/go-ethereum/wiki/Native-DApps:-Go-bindings-to-Ethereum-contracts) wiki page for details. |
 | `bootnode` | Stripped down version of our Ethereum client implementation that only takes part in the network node discovery protocol, but does not run any of the higher level application protocols. It can be used as a lightweight bootstrap node to aid in finding peers in private networks. |
-| `disasm` | Bytecode disassembler to convert EVM (Ethereum Virtual Machine) bytecode into more user friendly assembly-like opcodes (e.g. `echo "6001" | disasm`). For details on the individual opcodes, please see pages 22-30 of the [Ethereum Yellow Paper](http://gavwood.com/paper.pdf). |
-| `evm` | Developer utility version of the EVM (Ethereum Virtual Machine) that is capable of running bytecode snippets within a configurable environment and execution mode. Its purpose is to allow insolated, fine-grained debugging of EVM opcodes (e.g. `evm --code 60ff60ff --debug`). |
+| `evm` | Developer utility version of the EVM (Ethereum Virtual Machine) that is capable of running bytecode snippets within a configurable environment and execution mode. Its purpose is to allow isolated, fine-grained debugging of EVM opcodes (e.g. `evm --code 60ff60ff --debug`). |
 | `gethrpctest` | Developer utility tool to support our [ethereum/rpc-test](https://github.com/ethereum/rpc-tests) test suite which validates baseline conformity to the [Ethereum JSON RPC](https://github.com/ethereum/wiki/wiki/JSON-RPC) specs. Please see the [test suite's readme](https://github.com/ethereum/rpc-tests/blob/master/README.md) for details. |
 | `rlpdump` | Developer utility tool to convert binary RLP ([Recursive Length Prefix](https://github.com/ethereum/wiki/wiki/RLP)) dumps (data encoding used by the Ethereum protocol both network as well as consensus wise) to user friendlier hierarchical representation (e.g. `rlpdump --hex CE0183FFFFFFC4C304050583616263`). |
+| `swarm`    | swarm daemon and tools. This is the entrypoint for the swarm network. `swarm --help` for command line options and subcommands. See https://swarm-guide.readthedocs.io for swarm documentation. |
+| `puppeth`    | a CLI wizard that aids in creating a new Ethereum network. |

 ## Running geth

@@ -69,21 +58,19 @@ the user doesn't care about years-old historical data, so we can fast-sync quick
 state of the network. To do so:

 ```
-$ geth --fast --cache=512 console
+$ geth console
 ```

 This command will:

- * Start geth in fast sync mode (`--fast`), causing it to download more data in exchange for avoiding
-   processing the entire history of the Ethereum network, which is very CPU intensive.
- * Bump the memory allowance of the database to 512MB (`--cache=512`), which can help significantly in
-   sync times especially for HDD users. This flag is optional and you can set it as high or as low as
-   you'd like, though we'd recommend the 512MB - 2GB range.
+ * Start geth in fast sync mode (default, can be changed with the `--syncmode` flag), causing it to
+   download more data in exchange for avoiding processing the entire history of the Ethereum network,
+   which is very CPU intensive.
 * Start up Geth's built-in interactive [JavaScript console](https://github.com/ethereum/go-ethereum/wiki/JavaScript-Console),
   (via the trailing `console` subcommand) through which you can invoke all official [`web3` methods](https://github.com/ethereum/wiki/wiki/JavaScript-API)
   as well as Geth's own [management APIs](https://github.com/ethereum/go-ethereum/wiki/Management-APIs).
   This too is optional and if you leave it out you can always attach to an already running Geth instance
-   with `geth --attach`.
+   with `geth attach`.

 ### Full node on the Ethereum test network

@@ -93,25 +80,50 @@ entire system. In other words, instead of attaching to the main network, you wan
 network with your node, which is fully equivalent to the main network, but with play-Ether only.

 ```
-$ geth --testnet --fast --cache=512 console
+$ geth --testnet console
 ```

-The `--fast`, `--cache` flags and `console` subcommand have the exact same meaning as above and they
-are equially useful on the testnet too. Please see above for their explanations if you've skipped to
-here.
+The `console` subcommand have the exact same meaning as above and they are equally useful on the
+testnet too. Please see above for their explanations if you've skipped to here.

 Specifying the `--testnet` flag however will reconfigure your Geth instance a bit:

 * Instead of using the default data directory (`~/.ethereum` on Linux for example), Geth will nest
-   itself one level deeper into a `testnet` subfolder (`~/.ethereum/testnet` on Linux).
+   itself one level deeper into a `testnet` subfolder (`~/.ethereum/testnet` on Linux). Note, on OSX
+   and Linux this also means that attaching to a running testnet node requires the use of a custom
+   endpoint since `geth attach` will try to attach to a production node endpoint by default. E.g.
+   `geth attach <datadir>/testnet/geth.ipc`. Windows users are not affected by this.
 * Instead of connecting the main Ethereum network, the client will connect to the test network,
   which uses different P2P bootnodes, different network IDs and genesis states.
-
+   
 *Note: Although there are some internal protective measures to prevent transactions from crossing
-over between the main network and test network (different starting nonces), you should make sure to
-always use separate accounts for play-money and real-money. Unless you manually move accounts, Geth
-will by default correctly separate the two networks and will not make any accounts available between
-them.*
+over between the main network and test network, you should make sure to always use separate accounts
+for play-money and real-money. Unless you manually move accounts, Geth will by default correctly
+separate the two networks and will not make any accounts available between them.*
+
+### Full node on the Rinkeby test network
+
+The above test network is a cross client one based on the ethash proof-of-work consensus algorithm. As such, it has certain extra overhead and is more susceptible to reorganization attacks due to the network's low difficulty / security. Go Ethereum also supports connecting to a proof-of-authority based test network called [*Rinkeby*](https://www.rinkeby.io) (operated by members of the community). This network is lighter, more secure, but is only supported by go-ethereum.
+
+```
+$ geth --rinkeby console
+```
+
+### Configuration
+
+As an alternative to passing the numerous flags to the `geth` binary, you can also pass a configuration file via:
+
+```
+$ geth --config /path/to/your_config.toml
+```
+
+To get an idea how the file should look like you can use the `dumpconfig` subcommand to export your existing configuration:
+
+```
+$ geth --your-favourite-flags dumpconfig
+```
+
+*Note: This works only with geth v1.6.0 and above.*

 #### Docker quick start

@@ -120,10 +132,12 @@ One of the quickest ways to get Ethereum up and running on your machine is by us
 ```
 docker run -d --name ethereum-node -v /Users/alice/ethereum:/root \
           -p 8545:8545 -p 30303:30303 \
-           ethereum/client-go --fast --cache=512
+           ethereum/client-go
 ```

-This will start geth in fast sync mode with a DB memory allowance of 512MB just as the above command does.  It will also create a persistent volume in your home directory for saving your blockchain as well as map the default ports. There is also an `alpine` tag available for a slim version of the image.
+This will start geth in fast-sync mode with a DB memory allowance of 1GB just as the above command does.  It will also create a persistent volume in your home directory for saving your blockchain as well as map the default ports. There is also an `alpine` tag available for a slim version of the image.
+
+Do not forget `--rpcaddr 0.0.0.0`, if you want to access RPC from other containers and/or hosts. By default, `geth` binds to the local interface and RPC endpoints is not accessible from the outside.

 ### Programatically interfacing Geth nodes

@@ -131,7 +145,7 @@ As a developer, sooner rather than later you'll want to start interacting with G
 network via your own programs and not manually through the console. To aid this, Geth has built in
 support for a JSON-RPC based APIs ([standard APIs](https://github.com/ethereum/wiki/wiki/JSON-RPC) and
 [Geth specific APIs](https://github.com/ethereum/go-ethereum/wiki/Management-APIs)). These can be
-exposed via HTTP, WebSockets and IPC (unix sockets on unix based platroms, and named pipes on Windows).
+exposed via HTTP, WebSockets and IPC (unix sockets on unix based platforms, and named pipes on Windows).

 The IPC interface is enabled by default and exposes all the APIs supported by Geth, whereas the HTTP
 and WS interfaces need to manually be enabled and only expose a subset of APIs due to security reasons.
@@ -174,6 +188,12 @@ and agree upon. This consists of a small JSON file (e.g. call it `genesis.json`)

 ```json
 {
+  "config": {
+        "chainId": 0,
+        "homesteadBlock": 0,
+        "eip155Block": 0,
+        "eip158Block": 0
+    },
  "alloc"      : {},
  "coinbase"   : "0x0000000000000000000000000000000000000000",
  "difficulty" : "0x20000",
@@ -253,7 +273,7 @@ instance for mining, run it with all your usual flags, extended by:
 $ geth <usual-flags> --mine --minerthreads=1 --etherbase=0x0000000000000000000000000000000000000000
 ```

-Which will start mining bocks and transactions on a single CPU thread, crediting all proceedings to
+Which will start mining blocks and transactions on a single CPU thread, crediting all proceedings to
 the account specified by `--etherbase`. You can further tune the mining by changing the default gas
 limit blocks converge to (`--targetgaslimit`) and the price transactions are accepted at (`--gasprice`).

@@ -273,7 +293,7 @@ Please make sure your contributions adhere to our coding guidelines:

 * Code must adhere to the official Go [formatting](https://golang.org/doc/effective_go.html#formatting) guidelines (i.e. uses [gofmt](https://golang.org/cmd/gofmt/)).
 * Code must be documented adhering to the official Go [commentary](https://golang.org/doc/effective_go.html#commentary) guidelines.
- * Pull requests need to be based on and opened against the `develop` branch.
+ * Pull requests need to be based on and opened against the `master` branch.
 * Commit messages should be prefixed with the package(s) they modify.
   * E.g. "eth, rpc: make trace configs optional"

--- a/2
+++ b/2
@@ -1 +1 @@
-1.5.0
+1.8.2
--- a/accounts/abi/abi.go
+++ b/accounts/abi/abi.go
@@ -17,14 +17,10 @@
 package abi

 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
-	"math/big"
-	"reflect"
-	"strings"
-
-	"github.com/ethereum/go-ethereum/common"
 )

 // The ABI holds information about a contract's context and available
@@ -55,302 +51,55 @@ func JSON(reader io.Reader) (ABI, error) {
 // methods string signature. (signature = baz(uint32,string32))
 func (abi ABI) Pack(name string, args ...interface{}) ([]byte, error) {
 	// Fetch the ABI of the requested method
-	var method Method
-
 	if name == "" {
-		method = abi.Constructor
-	} else {
-		m, exist := abi.Methods[name]
-		if !exist {
-			return nil, fmt.Errorf("method '%s' not found", name)
+		// constructor
+		arguments, err := abi.Constructor.Inputs.Pack(args...)
+		if err != nil {
+			return nil, err
 		}
-		method = m
+		return arguments, nil
+
 	}
-	arguments, err := method.pack(method, args...)
+	method, exist := abi.Methods[name]
+	if !exist {
+		return nil, fmt.Errorf("method '%s' not found", name)
+	}
+
+	arguments, err := method.Inputs.Pack(args...)
 	if err != nil {
 		return nil, err
 	}
 	// Pack up the method ID too if not a constructor and return
-	if name == "" {
-		return arguments, nil
-	}
 	return append(method.Id(), arguments...), nil
 }

-// toGoSliceType parses the input and casts it to the proper slice defined by the ABI
-// argument in T.
-func toGoSlice(i int, t Argument, output []byte) (interface{}, error) {
-	index := i * 32
-	// The slice must, at very least be large enough for the index+32 which is exactly the size required
-	// for the [offset in output, size of offset].
-	if index+32 > len(output) {
-		return nil, fmt.Errorf("abi: cannot marshal in to go slice: insufficient size output %d require %d", len(output), index+32)
-	}
-	elem := t.Type.Elem
-
-	// first we need to create a slice of the type
-	var refSlice reflect.Value
-	switch elem.T {
-	case IntTy, UintTy, BoolTy: // int, uint, bool can all be of type big int.
-		refSlice = reflect.ValueOf([]*big.Int(nil))
-	case AddressTy: // address must be of slice Address
-		refSlice = reflect.ValueOf([]common.Address(nil))
-	case HashTy: // hash must be of slice hash
-		refSlice = reflect.ValueOf([]common.Hash(nil))
-	case FixedBytesTy:
-		refSlice = reflect.ValueOf([][]byte(nil))
-	default: // no other types are supported
-		return nil, fmt.Errorf("abi: unsupported slice type %v", elem.T)
-	}
-
-	var slice []byte
-	var size int
-	var offset int
-	if t.Type.IsSlice {
-
-		// get the offset which determines the start of this array ...
-		offset = int(common.BytesToBig(output[index : index+32]).Uint64())
-		if offset+32 > len(output) {
-			return nil, fmt.Errorf("abi: cannot marshal in to go slice: offset %d would go over slice boundary (len=%d)", len(output), offset+32)
-		}
-
-		slice = output[offset:]
-		// ... starting with the size of the array in elements ...
-		size = int(common.BytesToBig(slice[:32]).Uint64())
-		slice = slice[32:]
-		// ... and make sure that we've at the very least the amount of bytes
-		// available in the buffer.
-		if size*32 > len(slice) {
-			return nil, fmt.Errorf("abi: cannot marshal in to go slice: insufficient size output %d require %d", len(output), offset+32+size*32)
-		}
-
-		// reslice to match the required size
-		slice = slice[:(size * 32)]
-	} else if t.Type.IsArray {
-		//get the number of elements in the array
-		size = t.Type.SliceSize
-
-		//check to make sure array size matches up
-		if index+32*size > len(output) {
-			return nil, fmt.Errorf("abi: cannot marshal in to go array: offset %d would go over slice boundary (len=%d)", len(output), index+32*size)
-		}
-		//slice is there for a fixed amount of times
-		slice = output[index : index+size*32]
-	}
-
-	for i := 0; i < size; i++ {
-		var (
-			inter        interface{}             // interface type
-			returnOutput = slice[i*32 : i*32+32] // the return output
-		)
-
-		// set inter to the correct type (cast)
-		switch elem.T {
-		case IntTy, UintTy:
-			inter = common.BytesToBig(returnOutput)
-		case BoolTy:
-			inter = common.BytesToBig(returnOutput).Uint64() > 0
-		case AddressTy:
-			inter = common.BytesToAddress(returnOutput)
-		case HashTy:
-			inter = common.BytesToHash(returnOutput)
-		case FixedBytesTy:
-			inter = returnOutput
-		}
-		// append the item to our reflect slice
-		refSlice = reflect.Append(refSlice, reflect.ValueOf(inter))
-	}
-
-	// return the interface
-	return refSlice.Interface(), nil
-}
-
-// toGoType parses the input and casts it to the proper type defined by the ABI
-// argument in T.
-func toGoType(i int, t Argument, output []byte) (interface{}, error) {
-	// we need to treat slices differently
-	if (t.Type.IsSlice || t.Type.IsArray) && t.Type.T != BytesTy && t.Type.T != StringTy && t.Type.T != FixedBytesTy {
-		return toGoSlice(i, t, output)
-	}
-
-	index := i * 32
-	if index+32 > len(output) {
-		return nil, fmt.Errorf("abi: cannot marshal in to go type: length insufficient %d require %d", len(output), index+32)
-	}
-
-	// Parse the given index output and check whether we need to read
-	// a different offset and length based on the type (i.e. string, bytes)
-	var returnOutput []byte
-	switch t.Type.T {
-	case StringTy, BytesTy: // variable arrays are written at the end of the return bytes
-		// parse offset from which we should start reading
-		offset := int(common.BytesToBig(output[index : index+32]).Uint64())
-		if offset+32 > len(output) {
-			return nil, fmt.Errorf("abi: cannot marshal in to go type: length insufficient %d require %d", len(output), offset+32)
-		}
-		// parse the size up until we should be reading
-		size := int(common.BytesToBig(output[offset : offset+32]).Uint64())
-		if offset+32+size > len(output) {
-			return nil, fmt.Errorf("abi: cannot marshal in to go type: length insufficient %d require %d", len(output), offset+32+size)
-		}
-
-		// get the bytes for this return value
-		returnOutput = output[offset+32 : offset+32+size]
-	default:
-		returnOutput = output[index : index+32]
-	}
-
-	// convert the bytes to whatever is specified by the ABI.
-	switch t.Type.T {
-	case IntTy, UintTy:
-		bigNum := common.BytesToBig(returnOutput)
-
-		// If the type is a integer convert to the integer type
-		// specified by the ABI.
-		switch t.Type.Kind {
-		case reflect.Uint8:
-			return uint8(bigNum.Uint64()), nil
-		case reflect.Uint16:
-			return uint16(bigNum.Uint64()), nil
-		case reflect.Uint32:
-			return uint32(bigNum.Uint64()), nil
-		case reflect.Uint64:
-			return uint64(bigNum.Uint64()), nil
-		case reflect.Int8:
-			return int8(bigNum.Int64()), nil
-		case reflect.Int16:
-			return int16(bigNum.Int64()), nil
-		case reflect.Int32:
-			return int32(bigNum.Int64()), nil
-		case reflect.Int64:
-			return int64(bigNum.Int64()), nil
-		case reflect.Ptr:
-			return bigNum, nil
-		}
-	case BoolTy:
-		return common.BytesToBig(returnOutput).Uint64() > 0, nil
-	case AddressTy:
-		return common.BytesToAddress(returnOutput), nil
-	case HashTy:
-		return common.BytesToHash(returnOutput), nil
-	case BytesTy, FixedBytesTy:
-		return returnOutput, nil
-	case StringTy:
-		return string(returnOutput), nil
-	}
-	return nil, fmt.Errorf("abi: unknown type %v", t.Type.T)
-}
-
-// these variable are used to determine certain types during type assertion for
-// assignment.
-var (
-	r_interSlice = reflect.TypeOf([]interface{}{})
-	r_hash       = reflect.TypeOf(common.Hash{})
-	r_bytes      = reflect.TypeOf([]byte{})
-	r_byte       = reflect.TypeOf(byte(0))
-)
-
 // Unpack output in v according to the abi specification
-func (abi ABI) Unpack(v interface{}, name string, output []byte) error {
-	var method = abi.Methods[name]
-
+func (abi ABI) Unpack(v interface{}, name string, output []byte) (err error) {
 	if len(output) == 0 {
 		return fmt.Errorf("abi: unmarshalling empty output")
 	}
-
-	// make sure the passed value is a pointer
-	valueOf := reflect.ValueOf(v)
-	if reflect.Ptr != valueOf.Kind() {
-		return fmt.Errorf("abi: Unpack(non-pointer %T)", v)
+	// since there can't be naming collisions with contracts and events,
+	// we need to decide whether we're calling a method or an event
+	if method, ok := abi.Methods[name]; ok {
+		if len(output)%32 != 0 {
+			return fmt.Errorf("abi: improperly formatted output")
+		}
+		return method.Outputs.Unpack(v, output)
+	} else if event, ok := abi.Events[name]; ok {
+		return event.Inputs.Unpack(v, output)
 	}
-
-	var (
-		value = valueOf.Elem()
-		typ   = value.Type()
-	)
-
-	if len(method.Outputs) > 1 {
-		switch value.Kind() {
-		// struct will match named return values to the struct's field
-		// names
-		case reflect.Struct:
-			for i := 0; i < len(method.Outputs); i++ {
-				marshalledValue, err := toGoType(i, method.Outputs[i], output)
-				if err != nil {
-					return err
-				}
-				reflectValue := reflect.ValueOf(marshalledValue)
-
-				for j := 0; j < typ.NumField(); j++ {
-					field := typ.Field(j)
-					// TODO read tags: `abi:"fieldName"`
-					if field.Name == strings.ToUpper(method.Outputs[i].Name[:1])+method.Outputs[i].Name[1:] {
-						if err := set(value.Field(j), reflectValue, method.Outputs[i]); err != nil {
-							return err
-						}
-					}
-				}
-			}
-		case reflect.Slice:
-			if !value.Type().AssignableTo(r_interSlice) {
-				return fmt.Errorf("abi: cannot marshal tuple in to slice %T (only []interface{} is supported)", v)
-			}
-
-			// if the slice already contains values, set those instead of the interface slice itself.
-			if value.Len() > 0 {
-				if len(method.Outputs) > value.Len() {
-					return fmt.Errorf("abi: cannot marshal in to slices of unequal size (require: %v, got: %v)", len(method.Outputs), value.Len())
-				}
-
-				for i := 0; i < len(method.Outputs); i++ {
-					marshalledValue, err := toGoType(i, method.Outputs[i], output)
-					if err != nil {
-						return err
-					}
-					reflectValue := reflect.ValueOf(marshalledValue)
-					if err := set(value.Index(i).Elem(), reflectValue, method.Outputs[i]); err != nil {
-						return err
-					}
-				}
-				return nil
-			}
-
-			// create a new slice and start appending the unmarshalled
-			// values to the new interface slice.
-			z := reflect.MakeSlice(typ, 0, len(method.Outputs))
-			for i := 0; i < len(method.Outputs); i++ {
-				marshalledValue, err := toGoType(i, method.Outputs[i], output)
-				if err != nil {
-					return err
-				}
-				z = reflect.Append(z, reflect.ValueOf(marshalledValue))
-			}
-			value.Set(z)
-		default:
-			return fmt.Errorf("abi: cannot unmarshal tuple in to %v", typ)
-		}
-
-	} else {
-		marshalledValue, err := toGoType(0, method.Outputs[0], output)
-		if err != nil {
-			return err
-		}
-		if err := set(value, reflect.ValueOf(marshalledValue), method.Outputs[0]); err != nil {
-			return err
-		}
-	}
-
-	return nil
+	return fmt.Errorf("abi: could not locate named method or event")
 }

+// UnmarshalJSON implements json.Unmarshaler interface
 func (abi *ABI) UnmarshalJSON(data []byte) error {
 	var fields []struct {
-		Type     string
-		Name     string
-		Constant bool
-		Indexed  bool
-		Inputs   []Argument
-		Outputs  []Argument
+		Type      string
+		Name      string
+		Constant  bool
+		Anonymous bool
+		Inputs    []Argument
+		Outputs   []Argument
 	}

 	if err := json.Unmarshal(data, &fields); err != nil {
@@ -375,11 +124,23 @@ func (abi *ABI) UnmarshalJSON(data []byte) error {
 			}
 		case "event":
 			abi.Events[field.Name] = Event{
-				Name:   field.Name,
-				Inputs: field.Inputs,
+				Name:      field.Name,
+				Anonymous: field.Anonymous,
+				Inputs:    field.Inputs,
 			}
 		}
 	}

 	return nil
 }
+
+// MethodById looks up a method by the 4-byte id
+// returns nil if none found
+func (abi *ABI) MethodById(sigdata []byte) (*Method, error) {
+	for _, method := range abi.Methods {
+		if bytes.Equal(method.Id(), sigdata[:4]) {
+			return &method, nil
+		}
+	}
+	return nil, fmt.Errorf("no method with id: %#x", sigdata[:4])
+}
--- a/accounts/abi/abi_test.go
+++ b/accounts/abi/abi_test.go
--- a/accounts/abi/argument.go
+++ b/accounts/abi/argument.go
@@ -19,6 +19,8 @@ package abi
 import (
 	"encoding/json"
 	"fmt"
+	"reflect"
+	"strings"
 )

 // Argument holds the name of the argument and the corresponding type.
@@ -29,21 +31,250 @@ type Argument struct {
 	Indexed bool // indexed is only used by events
 }

-func (a *Argument) UnmarshalJSON(data []byte) error {
+type Arguments []Argument
+
+// UnmarshalJSON implements json.Unmarshaler interface
+func (argument *Argument) UnmarshalJSON(data []byte) error {
 	var extarg struct {
-		Name string
-		Type string
+		Name    string
+		Type    string
+		Indexed bool
 	}
 	err := json.Unmarshal(data, &extarg)
 	if err != nil {
 		return fmt.Errorf("argument json err: %v", err)
 	}

-	a.Type, err = NewType(extarg.Type)
+	argument.Type, err = NewType(extarg.Type)
 	if err != nil {
 		return err
 	}
-	a.Name = extarg.Name
+	argument.Name = extarg.Name
+	argument.Indexed = extarg.Indexed

 	return nil
 }
+
+// LengthNonIndexed returns the number of arguments when not counting 'indexed' ones. Only events
+// can ever have 'indexed' arguments, it should always be false on arguments for method input/output
+func (arguments Arguments) LengthNonIndexed() int {
+	out := 0
+	for _, arg := range arguments {
+		if !arg.Indexed {
+			out++
+		}
+	}
+	return out
+}
+
+// NonIndexed returns the arguments with indexed arguments filtered out
+func (arguments Arguments) NonIndexed() Arguments {
+	var ret []Argument
+	for _, arg := range arguments {
+		if !arg.Indexed {
+			ret = append(ret, arg)
+		}
+	}
+	return ret
+}
+
+// isTuple returns true for non-atomic constructs, like (uint,uint) or uint[]
+func (arguments Arguments) isTuple() bool {
+	return len(arguments) > 1
+}
+
+// Unpack performs the operation hexdata -> Go format
+func (arguments Arguments) Unpack(v interface{}, data []byte) error {
+
+	// make sure the passed value is arguments pointer
+	if reflect.Ptr != reflect.ValueOf(v).Kind() {
+		return fmt.Errorf("abi: Unpack(non-pointer %T)", v)
+	}
+	marshalledValues, err := arguments.UnpackValues(data)
+	if err != nil {
+		return err
+	}
+	if arguments.isTuple() {
+		return arguments.unpackTuple(v, marshalledValues)
+	}
+	return arguments.unpackAtomic(v, marshalledValues)
+}
+
+func (arguments Arguments) unpackTuple(v interface{}, marshalledValues []interface{}) error {
+
+	var (
+		value = reflect.ValueOf(v).Elem()
+		typ   = value.Type()
+		kind  = value.Kind()
+	)
+
+	if err := requireUnpackKind(value, typ, kind, arguments); err != nil {
+		return err
+	}
+	// If the output interface is a struct, make sure names don't collide
+	if kind == reflect.Struct {
+		exists := make(map[string]bool)
+		for _, arg := range arguments {
+			field := capitalise(arg.Name)
+			if field == "" {
+				return fmt.Errorf("abi: purely underscored output cannot unpack to struct")
+			}
+			if exists[field] {
+				return fmt.Errorf("abi: multiple outputs mapping to the same struct field '%s'", field)
+			}
+			exists[field] = true
+		}
+	}
+	for i, arg := range arguments.NonIndexed() {
+
+		reflectValue := reflect.ValueOf(marshalledValues[i])
+
+		switch kind {
+		case reflect.Struct:
+			name := capitalise(arg.Name)
+			for j := 0; j < typ.NumField(); j++ {
+				// TODO read tags: `abi:"fieldName"`
+				if typ.Field(j).Name == name {
+					if err := set(value.Field(j), reflectValue, arg); err != nil {
+						return err
+					}
+				}
+			}
+		case reflect.Slice, reflect.Array:
+			if value.Len() < i {
+				return fmt.Errorf("abi: insufficient number of arguments for unpack, want %d, got %d", len(arguments), value.Len())
+			}
+			v := value.Index(i)
+			if err := requireAssignable(v, reflectValue); err != nil {
+				return err
+			}
+
+			if err := set(v.Elem(), reflectValue, arg); err != nil {
+				return err
+			}
+		default:
+			return fmt.Errorf("abi:[2] cannot unmarshal tuple in to %v", typ)
+		}
+	}
+	return nil
+}
+
+// unpackAtomic unpacks ( hexdata -> go ) a single value
+func (arguments Arguments) unpackAtomic(v interface{}, marshalledValues []interface{}) error {
+	if len(marshalledValues) != 1 {
+		return fmt.Errorf("abi: wrong length, expected single value, got %d", len(marshalledValues))
+	}
+	elem := reflect.ValueOf(v).Elem()
+	reflectValue := reflect.ValueOf(marshalledValues[0])
+	return set(elem, reflectValue, arguments.NonIndexed()[0])
+}
+
+// Computes the full size of an array;
+// i.e. counting nested arrays, which count towards size for unpacking.
+func getArraySize(arr *Type) int {
+	size := arr.Size
+	// Arrays can be nested, with each element being the same size
+	arr = arr.Elem
+	for arr.T == ArrayTy {
+		// Keep multiplying by elem.Size while the elem is an array.
+		size *= arr.Size
+		arr = arr.Elem
+	}
+	// Now we have the full array size, including its children.
+	return size
+}
+
+// UnpackValues can be used to unpack ABI-encoded hexdata according to the ABI-specification,
+// without supplying a struct to unpack into. Instead, this method returns a list containing the
+// values. An atomic argument will be a list with one element.
+func (arguments Arguments) UnpackValues(data []byte) ([]interface{}, error) {
+	retval := make([]interface{}, 0, arguments.LengthNonIndexed())
+	virtualArgs := 0
+	for index, arg := range arguments.NonIndexed() {
+		marshalledValue, err := toGoType((index+virtualArgs)*32, arg.Type, data)
+		if arg.Type.T == ArrayTy {
+			// If we have a static array, like [3]uint256, these are coded as
+			// just like uint256,uint256,uint256.
+			// This means that we need to add two 'virtual' arguments when
+			// we count the index from now on.
+			//
+			// Array values nested multiple levels deep are also encoded inline:
+			// [2][3]uint256: uint256,uint256,uint256,uint256,uint256,uint256
+			//
+			// Calculate the full array size to get the correct offset for the next argument.
+			// Decrement it by 1, as the normal index increment is still applied.
+			virtualArgs += getArraySize(&arg.Type) - 1
+		}
+		if err != nil {
+			return nil, err
+		}
+		retval = append(retval, marshalledValue)
+	}
+	return retval, nil
+}
+
+// PackValues performs the operation Go format -> Hexdata
+// It is the semantic opposite of UnpackValues
+func (arguments Arguments) PackValues(args []interface{}) ([]byte, error) {
+	return arguments.Pack(args...)
+}
+
+// Pack performs the operation Go format -> Hexdata
+func (arguments Arguments) Pack(args ...interface{}) ([]byte, error) {
+	// Make sure arguments match up and pack them
+	abiArgs := arguments
+	if len(args) != len(abiArgs) {
+		return nil, fmt.Errorf("argument count mismatch: %d for %d", len(args), len(abiArgs))
+	}
+	// variable input is the output appended at the end of packed
+	// output. This is used for strings and bytes types input.
+	var variableInput []byte
+
+	// input offset is the bytes offset for packed output
+	inputOffset := 0
+	for _, abiArg := range abiArgs {
+		if abiArg.Type.T == ArrayTy {
+			inputOffset += 32 * abiArg.Type.Size
+		} else {
+			inputOffset += 32
+		}
+	}
+	var ret []byte
+	for i, a := range args {
+		input := abiArgs[i]
+		// pack the input
+		packed, err := input.Type.pack(reflect.ValueOf(a))
+		if err != nil {
+			return nil, err
+		}
+		// check for a slice type (string, bytes, slice)
+		if input.Type.requiresLengthPrefix() {
+			// calculate the offset
+			offset := inputOffset + len(variableInput)
+			// set the offset
+			ret = append(ret, packNum(reflect.ValueOf(offset))...)
+			// Append the packed output to the variable input. The variable input
+			// will be appended at the end of the input.
+			variableInput = append(variableInput, packed...)
+		} else {
+			// append the packed value to the input
+			ret = append(ret, packed...)
+		}
+	}
+	// append the variable input at the end of the packed input
+	ret = append(ret, variableInput...)
+
+	return ret, nil
+}
+
+// capitalise makes the first character of a string upper case, also removing any
+// prefixing underscores from the variable names.
+func capitalise(input string) string {
+	for len(input) > 0 && input[0] == '_' {
+		input = input[1:]
+	}
+	if len(input) == 0 {
+		return ""
+	}
+	return strings.ToUpper(input[:1]) + input[1:]
+}
--- a/accounts/abi/bind/auth.go
+++ b/accounts/abi/bind/auth.go
@@ -22,7 +22,7 @@ import (
 	"io"
 	"io/ioutil"

-	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/accounts/keystore"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
@@ -35,7 +35,7 @@ func NewTransactor(keyin io.Reader, passphrase string) (*TransactOpts, error) {
 	if err != nil {
 		return nil, err
 	}
-	key, err := accounts.DecryptKey(json, passphrase)
+	key, err := keystore.DecryptKey(json, passphrase)
 	if err != nil {
 		return nil, err
 	}
@@ -52,7 +52,7 @@ func NewKeyedTransactor(key *ecdsa.PrivateKey) *TransactOpts {
 			if address != keyAddr {
 				return nil, errors.New("not authorized to sign this account")
 			}
-			signature, err := crypto.SignEthereum(signer.Hash(tx).Bytes(), key)
+			signature, err := crypto.Sign(signer.Hash(tx).Bytes(), key)
 			if err != nil {
 				return nil, err
 			}
--- a/accounts/abi/bind/backend.go
+++ b/accounts/abi/bind/backend.go
@@ -17,13 +17,13 @@
 package bind

 import (
+	"context"
 	"errors"
 	"math/big"

 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
-	"golang.org/x/net/context"
 )

 var (
@@ -52,12 +52,6 @@ type ContractCaller interface {
 	CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error)
 }

-// DeployBackend wraps the operations needed by WaitMined and WaitDeployed.
-type DeployBackend interface {
-	TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error)
-	CodeAt(ctx context.Context, account common.Address, blockNumber *big.Int) ([]byte, error)
-}
-
 // PendingContractCaller defines methods to perform contract calls on the pending state.
 // Call will try to discover this interface when access to the pending state is requested.
 // If the backend does not support the pending state, Call returns ErrNoPendingState.
@@ -85,13 +79,34 @@ type ContractTransactor interface {
 	// There is no guarantee that this is the true gas limit requirement as other
 	// transactions may be added or removed by miners, but it should provide a basis
 	// for setting a reasonable default.
-	EstimateGas(ctx context.Context, call ethereum.CallMsg) (usedGas *big.Int, err error)
+	EstimateGas(ctx context.Context, call ethereum.CallMsg) (gas uint64, err error)
 	// SendTransaction injects the transaction into the pending pool for execution.
 	SendTransaction(ctx context.Context, tx *types.Transaction) error
 }

+// ContractFilterer defines the methods needed to access log events using one-off
+// queries or continuous event subscriptions.
+type ContractFilterer interface {
+	// FilterLogs executes a log filter operation, blocking during execution and
+	// returning all the results in one batch.
+	//
+	// TODO(karalabe): Deprecate when the subscription one can return past data too.
+	FilterLogs(ctx context.Context, query ethereum.FilterQuery) ([]types.Log, error)
+
+	// SubscribeFilterLogs creates a background log filtering operation, returning
+	// a subscription immediately, which can be used to stream the found events.
+	SubscribeFilterLogs(ctx context.Context, query ethereum.FilterQuery, ch chan<- types.Log) (ethereum.Subscription, error)
+}
+
+// DeployBackend wraps the operations needed by WaitMined and WaitDeployed.
+type DeployBackend interface {
+	TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error)
+	CodeAt(ctx context.Context, account common.Address, blockNumber *big.Int) ([]byte, error)
+}
+
 // ContractBackend defines the methods needed to work with contracts on a read-write basis.
 type ContractBackend interface {
 	ContractCaller
 	ContractTransactor
+	ContractFilterer
 }
--- a/accounts/abi/bind/backends/simulated.go
+++ b/accounts/abi/bind/backends/simulated.go
@@ -17,31 +17,35 @@
 package backends

 import (
+	"context"
 	"errors"
 	"fmt"
 	"math/big"
 	"sync"
+	"time"

 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/accounts/abi/bind"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/bloombits"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/ethereum/go-ethereum/eth/filters"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/params"
-	"golang.org/x/net/context"
+	"github.com/ethereum/go-ethereum/rpc"
 )

-// Default chain configuration which sets homestead phase at block 0 (i.e. no frontier)
-var chainConfig = &params.ChainConfig{HomesteadBlock: big.NewInt(0), EIP150Block: new(big.Int), EIP158Block: new(big.Int)}
-
 // This nil assignment ensures compile time that SimulatedBackend implements bind.ContractBackend.
 var _ bind.ContractBackend = (*SimulatedBackend)(nil)

 var errBlockNumberUnsupported = errors.New("SimulatedBackend cannot access blocks other than the latest block")
+var errGasEstimationFailed = errors.New("gas required exceeds allowance or always failing transaction")

 // SimulatedBackend implements bind.ContractBackend, simulating a blockchain in
 // the background. Its main purpose is to allow easily testing contract bindings.
@@ -53,16 +57,25 @@ type SimulatedBackend struct {
 	pendingBlock *types.Block   // Currently pending block that will be imported on request
 	pendingState *state.StateDB // Currently pending state that will be the active on on request

+	events *filters.EventSystem // Event system for filtering log events live
+
 	config *params.ChainConfig
 }

 // NewSimulatedBackend creates a new binding backend using a simulated blockchain
 // for testing purposes.
-func NewSimulatedBackend(accounts ...core.GenesisAccount) *SimulatedBackend {
+func NewSimulatedBackend(alloc core.GenesisAlloc) *SimulatedBackend {
 	database, _ := ethdb.NewMemDatabase()
-	core.WriteGenesisBlockForTesting(database, accounts...)
-	blockchain, _ := core.NewBlockChain(database, chainConfig, new(core.FakePow), new(event.TypeMux))
-	backend := &SimulatedBackend{database: database, blockchain: blockchain}
+	genesis := core.Genesis{Config: params.AllEthashProtocolChanges, Alloc: alloc}
+	genesis.MustCommit(database)
+	blockchain, _ := core.NewBlockChain(database, nil, genesis.Config, ethash.NewFaker(), vm.Config{})
+
+	backend := &SimulatedBackend{
+		database:   database,
+		blockchain: blockchain,
+		config:     genesis.Config,
+		events:     filters.NewEventSystem(new(event.TypeMux), &filterBackend{database, blockchain}, false),
+	}
 	backend.rollback()
 	return backend
 }
@@ -88,9 +101,11 @@ func (b *SimulatedBackend) Rollback() {
 }

 func (b *SimulatedBackend) rollback() {
-	blocks, _ := core.GenerateChain(chainConfig, b.blockchain.CurrentBlock(), b.database, 1, func(int, *core.BlockGen) {})
+	blocks, _ := core.GenerateChain(b.config, b.blockchain.CurrentBlock(), ethash.NewFaker(), b.database, 1, func(int, *core.BlockGen) {})
+	statedb, _ := b.blockchain.State()
+
 	b.pendingBlock = blocks[0]
-	b.pendingState, _ = state.New(b.pendingBlock.Root(), b.database)
+	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database())
 }

 // CodeAt returns the code associated with a certain account in the blockchain.
@@ -144,7 +159,8 @@ func (b *SimulatedBackend) StorageAt(ctx context.Context, contract common.Addres

 // TransactionReceipt returns the receipt of a transaction.
 func (b *SimulatedBackend) TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error) {
-	return core.GetReceipt(b.database, txHash), nil
+	receipt, _, _, _ := core.GetReceipt(b.database, txHash)
+	return receipt, nil
 }

 // PendingCodeAt returns the code associated with an account in the pending state.
@@ -167,7 +183,7 @@ func (b *SimulatedBackend) CallContract(ctx context.Context, call ethereum.CallM
 	if err != nil {
 		return nil, err
 	}
-	rval, _, err := b.callContract(ctx, call, b.blockchain.CurrentBlock(), state)
+	rval, _, _, err := b.callContract(ctx, call, b.blockchain.CurrentBlock(), state)
 	return rval, err
 }

@@ -177,7 +193,7 @@ func (b *SimulatedBackend) PendingCallContract(ctx context.Context, call ethereu
 	defer b.mu.Unlock()
 	defer b.pendingState.RevertToSnapshot(b.pendingState.Snapshot())

-	rval, _, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
+	rval, _, _, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
 	return rval, err
 }

@@ -198,37 +214,80 @@ func (b *SimulatedBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error

 // EstimateGas executes the requested code against the currently pending block/state and
 // returns the used amount of gas.
-func (b *SimulatedBackend) EstimateGas(ctx context.Context, call ethereum.CallMsg) (*big.Int, error) {
+func (b *SimulatedBackend) EstimateGas(ctx context.Context, call ethereum.CallMsg) (uint64, error) {
 	b.mu.Lock()
 	defer b.mu.Unlock()
-	defer b.pendingState.RevertToSnapshot(b.pendingState.Snapshot())

-	_, gas, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
-	return gas, err
+	// Determine the lowest and highest possible gas limits to binary search in between
+	var (
+		lo  uint64 = params.TxGas - 1
+		hi  uint64
+		cap uint64
+	)
+	if call.Gas >= params.TxGas {
+		hi = call.Gas
+	} else {
+		hi = b.pendingBlock.GasLimit()
+	}
+	cap = hi
+
+	// Create a helper to check if a gas allowance results in an executable transaction
+	executable := func(gas uint64) bool {
+		call.Gas = gas
+
+		snapshot := b.pendingState.Snapshot()
+		_, _, failed, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
+		b.pendingState.RevertToSnapshot(snapshot)
+
+		if err != nil || failed {
+			return false
+		}
+		return true
+	}
+	// Execute the binary search and hone in on an executable gas limit
+	for lo+1 < hi {
+		mid := (hi + lo) / 2
+		if !executable(mid) {
+			lo = mid
+		} else {
+			hi = mid
+		}
+	}
+	// Reject the transaction as invalid if it still fails at the highest allowance
+	if hi == cap {
+		if !executable(hi) {
+			return 0, errGasEstimationFailed
+		}
+	}
+	return hi, nil
 }

-// callContract implemens common code between normal and pending contract calls.
+// callContract implements common code between normal and pending contract calls.
 // state is modified during execution, make sure to copy it if necessary.
-func (b *SimulatedBackend) callContract(ctx context.Context, call ethereum.CallMsg, block *types.Block, statedb *state.StateDB) ([]byte, *big.Int, error) {
+func (b *SimulatedBackend) callContract(ctx context.Context, call ethereum.CallMsg, block *types.Block, statedb *state.StateDB) ([]byte, uint64, bool, error) {
 	// Ensure message is initialized properly.
 	if call.GasPrice == nil {
 		call.GasPrice = big.NewInt(1)
 	}
-	if call.Gas == nil || call.Gas.BitLen() == 0 {
-		call.Gas = big.NewInt(50000000)
+	if call.Gas == 0 {
+		call.Gas = 50000000
 	}
 	if call.Value == nil {
 		call.Value = new(big.Int)
 	}
 	// Set infinite balance to the fake caller account.
 	from := statedb.GetOrNewStateObject(call.From)
-	from.SetBalance(common.MaxBig)
+	from.SetBalance(math.MaxBig256)
 	// Execute the call.
 	msg := callmsg{call}
-	vmenv := core.NewEnv(statedb, chainConfig, b.blockchain, msg, block.Header(), vm.Config{})
-	gaspool := new(core.GasPool).AddGas(common.MaxBig)
-	ret, gasUsed, _, err := core.NewStateTransition(vmenv, msg, gaspool).TransitionDb()
-	return ret, gasUsed, err
+
+	evmContext := core.NewEVMContext(msg, block.Header(), b.blockchain, nil)
+	// Create a new environment which holds all relevant information
+	// about the transaction and calling mechanisms.
+	vmenv := vm.NewEVM(evmContext, statedb, b.config, vm.Config{})
+	gaspool := new(core.GasPool).AddGas(math.MaxUint64)
+
+	return core.NewStateTransition(vmenv, msg, gaspool).TransitionDb()
 }

 // SendTransaction updates the pending block to include the given transaction.
@@ -246,14 +305,96 @@ func (b *SimulatedBackend) SendTransaction(ctx context.Context, tx *types.Transa
 		panic(fmt.Errorf("invalid transaction nonce: got %d, want %d", tx.Nonce(), nonce))
 	}

-	blocks, _ := core.GenerateChain(chainConfig, b.blockchain.CurrentBlock(), b.database, 1, func(number int, block *core.BlockGen) {
+	blocks, _ := core.GenerateChain(b.config, b.blockchain.CurrentBlock(), ethash.NewFaker(), b.database, 1, func(number int, block *core.BlockGen) {
 		for _, tx := range b.pendingBlock.Transactions() {
 			block.AddTx(tx)
 		}
 		block.AddTx(tx)
 	})
+	statedb, _ := b.blockchain.State()
+
 	b.pendingBlock = blocks[0]
-	b.pendingState, _ = state.New(b.pendingBlock.Root(), b.database)
+	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database())
+	return nil
+}
+
+// FilterLogs executes a log filter operation, blocking during execution and
+// returning all the results in one batch.
+//
+// TODO(karalabe): Deprecate when the subscription one can return past data too.
+func (b *SimulatedBackend) FilterLogs(ctx context.Context, query ethereum.FilterQuery) ([]types.Log, error) {
+	// Initialize unset filter boundaried to run from genesis to chain head
+	from := int64(0)
+	if query.FromBlock != nil {
+		from = query.FromBlock.Int64()
+	}
+	to := int64(-1)
+	if query.ToBlock != nil {
+		to = query.ToBlock.Int64()
+	}
+	// Construct and execute the filter
+	filter := filters.New(&filterBackend{b.database, b.blockchain}, from, to, query.Addresses, query.Topics)
+
+	logs, err := filter.Logs(ctx)
+	if err != nil {
+		return nil, err
+	}
+	res := make([]types.Log, len(logs))
+	for i, log := range logs {
+		res[i] = *log
+	}
+	return res, nil
+}
+
+// SubscribeFilterLogs creates a background log filtering operation, returning a
+// subscription immediately, which can be used to stream the found events.
+func (b *SimulatedBackend) SubscribeFilterLogs(ctx context.Context, query ethereum.FilterQuery, ch chan<- types.Log) (ethereum.Subscription, error) {
+	// Subscribe to contract events
+	sink := make(chan []*types.Log)
+
+	sub, err := b.events.SubscribeLogs(query, sink)
+	if err != nil {
+		return nil, err
+	}
+	// Since we're getting logs in batches, we need to flatten them into a plain stream
+	return event.NewSubscription(func(quit <-chan struct{}) error {
+		defer sub.Unsubscribe()
+		for {
+			select {
+			case logs := <-sink:
+				for _, log := range logs {
+					select {
+					case ch <- *log:
+					case err := <-sub.Err():
+						return err
+					case <-quit:
+						return nil
+					}
+				}
+			case err := <-sub.Err():
+				return err
+			case <-quit:
+				return nil
+			}
+		}
+	}), nil
+}
+
+// AdjustTime adds a time shift to the simulated clock.
+func (b *SimulatedBackend) AdjustTime(adjustment time.Duration) error {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	blocks, _ := core.GenerateChain(b.config, b.blockchain.CurrentBlock(), ethash.NewFaker(), b.database, 1, func(number int, block *core.BlockGen) {
+		for _, tx := range b.pendingBlock.Transactions() {
+			block.AddTx(tx)
+		}
+		block.OffsetTime(int64(adjustment.Seconds()))
+	})
+	statedb, _ := b.blockchain.State()
+
+	b.pendingBlock = blocks[0]
+	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database())
+
 	return nil
 }

@@ -267,6 +408,60 @@ func (m callmsg) Nonce() uint64        { return 0 }
 func (m callmsg) CheckNonce() bool     { return false }
 func (m callmsg) To() *common.Address  { return m.CallMsg.To }
 func (m callmsg) GasPrice() *big.Int   { return m.CallMsg.GasPrice }
-func (m callmsg) Gas() *big.Int        { return m.CallMsg.Gas }
+func (m callmsg) Gas() uint64          { return m.CallMsg.Gas }
 func (m callmsg) Value() *big.Int      { return m.CallMsg.Value }
 func (m callmsg) Data() []byte         { return m.CallMsg.Data }
+
+// filterBackend implements filters.Backend to support filtering for logs without
+// taking bloom-bits acceleration structures into account.
+type filterBackend struct {
+	db ethdb.Database
+	bc *core.BlockChain
+}
+
+func (fb *filterBackend) ChainDb() ethdb.Database  { return fb.db }
+func (fb *filterBackend) EventMux() *event.TypeMux { panic("not supported") }
+
+func (fb *filterBackend) HeaderByNumber(ctx context.Context, block rpc.BlockNumber) (*types.Header, error) {
+	if block == rpc.LatestBlockNumber {
+		return fb.bc.CurrentHeader(), nil
+	}
+	return fb.bc.GetHeaderByNumber(uint64(block.Int64())), nil
+}
+
+func (fb *filterBackend) GetReceipts(ctx context.Context, hash common.Hash) (types.Receipts, error) {
+	return core.GetBlockReceipts(fb.db, hash, core.GetBlockNumber(fb.db, hash)), nil
+}
+
+func (fb *filterBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*types.Log, error) {
+	receipts := core.GetBlockReceipts(fb.db, hash, core.GetBlockNumber(fb.db, hash))
+	if receipts == nil {
+		return nil, nil
+	}
+	logs := make([][]*types.Log, len(receipts))
+	for i, receipt := range receipts {
+		logs[i] = receipt.Logs
+	}
+	return logs, nil
+}
+
+func (fb *filterBackend) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription {
+	return event.NewSubscription(func(quit <-chan struct{}) error {
+		<-quit
+		return nil
+	})
+}
+func (fb *filterBackend) SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription {
+	return fb.bc.SubscribeChainEvent(ch)
+}
+func (fb *filterBackend) SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent) event.Subscription {
+	return fb.bc.SubscribeRemovedLogsEvent(ch)
+}
+func (fb *filterBackend) SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription {
+	return fb.bc.SubscribeLogsEvent(ch)
+}
+
+func (fb *filterBackend) BloomStatus() (uint64, uint64) { return 4096, 0 }
+func (fb *filterBackend) ServiceFilter(ctx context.Context, ms *bloombits.MatcherSession) {
+	panic("not supported")
+}
--- a/accounts/abi/bind/base.go
+++ b/accounts/abi/bind/base.go
@@ -17,6 +17,7 @@
 package bind

 import (
+	"context"
 	"errors"
 	"fmt"
 	"math/big"
@@ -26,7 +27,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
-	"golang.org/x/net/context"
+	"github.com/ethereum/go-ethereum/event"
 )

 // SignerFn is a signer function callback when a contract requires a method to
@@ -35,7 +36,8 @@ type SignerFn func(types.Signer, common.Address, *types.Transaction) (*types.Tra

 // CallOpts is the collection of options to fine tune a contract call request.
 type CallOpts struct {
-	Pending bool // Whether to operate on the pending state or the last known one
+	Pending bool           // Whether to operate on the pending state or the last known one
+	From    common.Address // Optional the sender address, otherwise the first account is used

 	Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
 }
@@ -49,11 +51,27 @@ type TransactOpts struct {

 	Value    *big.Int // Funds to transfer along along the transaction (nil = 0 = no funds)
 	GasPrice *big.Int // Gas price to use for the transaction execution (nil = gas price oracle)
-	GasLimit *big.Int // Gas limit to set for the transaction execution (nil = estimate + 10%)
+	GasLimit uint64   // Gas limit to set for the transaction execution (0 = estimate)

 	Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
 }

+// FilterOpts is the collection of options to fine tune filtering for events
+// within a bound contract.
+type FilterOpts struct {
+	Start uint64  // Start of the queried range
+	End   *uint64 // End of the range (nil = latest)
+
+	Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
+}
+
+// WatchOpts is the collection of options to fine tune subscribing for events
+// within a bound contract.
+type WatchOpts struct {
+	Start   *uint64         // Start of the queried range (nil = latest)
+	Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
+}
+
 // BoundContract is the base wrapper object that reflects a contract on the
 // Ethereum network. It contains a collection of methods that are used by the
 // higher level contract bindings to operate.
@@ -62,16 +80,18 @@ type BoundContract struct {
 	abi        abi.ABI            // Reflect based ABI to access the correct Ethereum methods
 	caller     ContractCaller     // Read interface to interact with the blockchain
 	transactor ContractTransactor // Write interface to interact with the blockchain
+	filterer   ContractFilterer   // Event filtering to interact with the blockchain
 }

 // NewBoundContract creates a low level contract interface through which calls
 // and transactions may be made through.
-func NewBoundContract(address common.Address, abi abi.ABI, caller ContractCaller, transactor ContractTransactor) *BoundContract {
+func NewBoundContract(address common.Address, abi abi.ABI, caller ContractCaller, transactor ContractTransactor, filterer ContractFilterer) *BoundContract {
 	return &BoundContract{
 		address:    address,
 		abi:        abi,
 		caller:     caller,
 		transactor: transactor,
+		filterer:   filterer,
 	}
 }

@@ -79,7 +99,7 @@ func NewBoundContract(address common.Address, abi abi.ABI, caller ContractCaller
 // deployment address with a Go wrapper.
 func DeployContract(opts *TransactOpts, abi abi.ABI, bytecode []byte, backend ContractBackend, params ...interface{}) (common.Address, *types.Transaction, *BoundContract, error) {
 	// Otherwise try to deploy the contract
-	c := NewBoundContract(common.Address{}, abi, backend, backend)
+	c := NewBoundContract(common.Address{}, abi, backend, backend, backend)

 	input, err := c.abi.Pack("", params...)
 	if err != nil {
@@ -108,7 +128,7 @@ func (c *BoundContract) Call(opts *CallOpts, result interface{}, method string,
 		return err
 	}
 	var (
-		msg    = ethereum.CallMsg{To: &c.address, Data: input}
+		msg    = ethereum.CallMsg{From: opts.From, To: &c.address, Data: input}
 		ctx    = ensureContext(opts.Context)
 		code   []byte
 		output []byte
@@ -170,7 +190,7 @@ func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, i
 	if value == nil {
 		value = new(big.Int)
 	}
-	nonce := uint64(0)
+	var nonce uint64
 	if opts.Nonce == nil {
 		nonce, err = c.transactor.PendingNonceAt(ensureContext(opts.Context), opts.From)
 		if err != nil {
@@ -188,7 +208,7 @@ func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, i
 		}
 	}
 	gasLimit := opts.GasLimit
-	if gasLimit == nil {
+	if gasLimit == 0 {
 		// Gas estimation cannot succeed without code for method invocations
 		if contract != nil {
 			if code, err := c.transactor.PendingCodeAt(ensureContext(opts.Context), c.address); err != nil {
@@ -224,6 +244,104 @@ func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, i
 	return signedTx, nil
 }

+// FilterLogs filters contract logs for past blocks, returning the necessary
+// channels to construct a strongly typed bound iterator on top of them.
+func (c *BoundContract) FilterLogs(opts *FilterOpts, name string, query ...[]interface{}) (chan types.Log, event.Subscription, error) {
+	// Don't crash on a lazy user
+	if opts == nil {
+		opts = new(FilterOpts)
+	}
+	// Append the event selector to the query parameters and construct the topic set
+	query = append([][]interface{}{{c.abi.Events[name].Id()}}, query...)
+
+	topics, err := makeTopics(query...)
+	if err != nil {
+		return nil, nil, err
+	}
+	// Start the background filtering
+	logs := make(chan types.Log, 128)
+
+	config := ethereum.FilterQuery{
+		Addresses: []common.Address{c.address},
+		Topics:    topics,
+		FromBlock: new(big.Int).SetUint64(opts.Start),
+	}
+	if opts.End != nil {
+		config.ToBlock = new(big.Int).SetUint64(*opts.End)
+	}
+	/* TODO(karalabe): Replace the rest of the method below with this when supported
+	sub, err := c.filterer.SubscribeFilterLogs(ensureContext(opts.Context), config, logs)
+	*/
+	buff, err := c.filterer.FilterLogs(ensureContext(opts.Context), config)
+	if err != nil {
+		return nil, nil, err
+	}
+	sub, err := event.NewSubscription(func(quit <-chan struct{}) error {
+		for _, log := range buff {
+			select {
+			case logs <- log:
+			case <-quit:
+				return nil
+			}
+		}
+		return nil
+	}), nil
+
+	if err != nil {
+		return nil, nil, err
+	}
+	return logs, sub, nil
+}
+
+// WatchLogs filters subscribes to contract logs for future blocks, returning a
+// subscription object that can be used to tear down the watcher.
+func (c *BoundContract) WatchLogs(opts *WatchOpts, name string, query ...[]interface{}) (chan types.Log, event.Subscription, error) {
+	// Don't crash on a lazy user
+	if opts == nil {
+		opts = new(WatchOpts)
+	}
+	// Append the event selector to the query parameters and construct the topic set
+	query = append([][]interface{}{{c.abi.Events[name].Id()}}, query...)
+
+	topics, err := makeTopics(query...)
+	if err != nil {
+		return nil, nil, err
+	}
+	// Start the background filtering
+	logs := make(chan types.Log, 128)
+
+	config := ethereum.FilterQuery{
+		Addresses: []common.Address{c.address},
+		Topics:    topics,
+	}
+	if opts.Start != nil {
+		config.FromBlock = new(big.Int).SetUint64(*opts.Start)
+	}
+	sub, err := c.filterer.SubscribeFilterLogs(ensureContext(opts.Context), config, logs)
+	if err != nil {
+		return nil, nil, err
+	}
+	return logs, sub, nil
+}
+
+// UnpackLog unpacks a retrieved log into the provided output structure.
+func (c *BoundContract) UnpackLog(out interface{}, event string, log types.Log) error {
+	if len(log.Data) > 0 {
+		if err := c.abi.Unpack(out, event, log.Data); err != nil {
+			return err
+		}
+	}
+	var indexed abi.Arguments
+	for _, arg := range c.abi.Events[event].Inputs {
+		if arg.Indexed {
+			indexed = append(indexed, arg)
+		}
+	}
+	return parseTopics(out, indexed, log.Topics[1:])
+}
+
+// ensureContext is a helper method to ensure a context is not nil, even if the
+// user specified it as such.
 func ensureContext(ctx context.Context) context.Context {
 	if ctx == nil {
 		return context.TODO()
--- a/accounts/abi/bind/bind.go
+++ b/accounts/abi/bind/bind.go
@@ -63,10 +63,11 @@ func Bind(types []string, abis []string, bytecodes []string, pkg string, lang La
 			return r
 		}, abis[i])

-		// Extract the call and transact methods, and sort them alphabetically
+		// Extract the call and transact methods; events; and sort them alphabetically
 		var (
 			calls     = make(map[string]*tmplMethod)
 			transacts = make(map[string]*tmplMethod)
+			events    = make(map[string]*tmplEvent)
 		)
 		for _, original := range evmABI.Methods {
 			// Normalize the method for capital cases and non-anonymous inputs/outputs
@@ -89,11 +90,33 @@ func Bind(types []string, abis []string, bytecodes []string, pkg string, lang La
 			}
 			// Append the methods to the call or transact lists
 			if original.Const {
-				calls[original.Name] = &tmplMethod{Original: original, Normalized: normalized, Structured: structured(original)}
+				calls[original.Name] = &tmplMethod{Original: original, Normalized: normalized, Structured: structured(original.Outputs)}
 			} else {
-				transacts[original.Name] = &tmplMethod{Original: original, Normalized: normalized, Structured: structured(original)}
+				transacts[original.Name] = &tmplMethod{Original: original, Normalized: normalized, Structured: structured(original.Outputs)}
 			}
 		}
+		for _, original := range evmABI.Events {
+			// Skip anonymous events as they don't support explicit filtering
+			if original.Anonymous {
+				continue
+			}
+			// Normalize the event for capital cases and non-anonymous outputs
+			normalized := original
+			normalized.Name = methodNormalizer[lang](original.Name)
+
+			normalized.Inputs = make([]abi.Argument, len(original.Inputs))
+			copy(normalized.Inputs, original.Inputs)
+			for j, input := range normalized.Inputs {
+				// Indexed fields are input, non-indexed ones are outputs
+				if input.Indexed {
+					if input.Name == "" {
+						normalized.Inputs[j].Name = fmt.Sprintf("arg%d", j)
+					}
+				}
+			}
+			// Append the event to the accumulator list
+			events[original.Name] = &tmplEvent{Original: original, Normalized: normalized}
+		}
 		contracts[types[i]] = &tmplContract{
 			Type:        capitalise(types[i]),
 			InputABI:    strings.Replace(strippedABI, "\"", "\\\"", -1),
@@ -101,6 +124,7 @@ func Bind(types []string, abis []string, bytecodes []string, pkg string, lang La
 			Constructor: evmABI.Constructor,
 			Calls:       calls,
 			Transacts:   transacts,
+			Events:      events,
 		}
 	}
 	// Generate the contract template data content and render it
@@ -111,10 +135,11 @@ func Bind(types []string, abis []string, bytecodes []string, pkg string, lang La
 	buffer := new(bytes.Buffer)

 	funcs := map[string]interface{}{
-		"bindtype":     bindType[lang],
-		"namedtype":    namedType[lang],
-		"capitalise":   capitalise,
-		"decapitalise": decapitalise,
+		"bindtype":      bindType[lang],
+		"bindtopictype": bindTopicType[lang],
+		"namedtype":     namedType[lang],
+		"capitalise":    capitalise,
+		"decapitalise":  decapitalise,
 	}
 	tmpl := template.Must(template.New("").Funcs(funcs).Parse(tmplSource[lang]))
 	if err := tmpl.Execute(buffer, data); err != nil {
@@ -122,138 +147,194 @@ func Bind(types []string, abis []string, bytecodes []string, pkg string, lang La
 	}
 	// For Go bindings pass the code through goimports to clean it up and double check
 	if lang == LangGo {
-		code, err := imports.Process("", buffer.Bytes(), nil)
+		code, err := imports.Process(".", buffer.Bytes(), nil)
 		if err != nil {
 			return "", fmt.Errorf("%v\n%s", err, buffer)
 		}
 		return string(code), nil
 	}
 	// For all others just return as is for now
-	return string(buffer.Bytes()), nil
+	return buffer.String(), nil
 }

 // bindType is a set of type binders that convert Solidity types to some supported
-// programming language.
+// programming language types.
 var bindType = map[Lang]func(kind abi.Type) string{
 	LangGo:   bindTypeGo,
 	LangJava: bindTypeJava,
 }

+// Helper function for the binding generators.
+// It reads the unmatched characters after the inner type-match,
+//  (since the inner type is a prefix of the total type declaration),
+//  looks for valid arrays (possibly a dynamic one) wrapping the inner type,
+//  and returns the sizes of these arrays.
+//
+// Returned array sizes are in the same order as solidity signatures; inner array size first.
+// Array sizes may also be "", indicating a dynamic array.
+func wrapArray(stringKind string, innerLen int, innerMapping string) (string, []string) {
+	remainder := stringKind[innerLen:]
+	//find all the sizes
+	matches := regexp.MustCompile(`\[(\d*)\]`).FindAllStringSubmatch(remainder, -1)
+	parts := make([]string, 0, len(matches))
+	for _, match := range matches {
+		//get group 1 from the regex match
+		parts = append(parts, match[1])
+	}
+	return innerMapping, parts
+}
+
+// Translates the array sizes to a Go-lang declaration of a (nested) array of the inner type.
+// Simply returns the inner type if arraySizes is empty.
+func arrayBindingGo(inner string, arraySizes []string) string {
+	out := ""
+	//prepend all array sizes, from outer (end arraySizes) to inner (start arraySizes)
+	for i := len(arraySizes) - 1; i >= 0; i-- {
+		out += "[" + arraySizes[i] + "]"
+	}
+	out += inner
+	return out
+}
+
 // bindTypeGo converts a Solidity type to a Go one. Since there is no clear mapping
 // from all Solidity types to Go ones (e.g. uint17), those that cannot be exactly
 // mapped will use an upscaled type (e.g. *big.Int).
 func bindTypeGo(kind abi.Type) string {
 	stringKind := kind.String()
+	innerLen, innerMapping := bindUnnestedTypeGo(stringKind)
+	return arrayBindingGo(wrapArray(stringKind, innerLen, innerMapping))
+}
+
+// The inner function of bindTypeGo, this finds the inner type of stringKind.
+// (Or just the type itself if it is not an array or slice)
+// The length of the matched part is returned, with the the translated type.
+func bindUnnestedTypeGo(stringKind string) (int, string) {

 	switch {
 	case strings.HasPrefix(stringKind, "address"):
-		parts := regexp.MustCompile("address(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
-		if len(parts) != 2 {
-			return stringKind
-		}
-		return fmt.Sprintf("%scommon.Address", parts[1])
+		return len("address"), "common.Address"

 	case strings.HasPrefix(stringKind, "bytes"):
-		parts := regexp.MustCompile("bytes([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
-		if len(parts) != 3 {
-			return stringKind
-		}
-		return fmt.Sprintf("%s[%s]byte", parts[2], parts[1])
+		parts := regexp.MustCompile(`bytes([0-9]*)`).FindStringSubmatch(stringKind)
+		return len(parts[0]), fmt.Sprintf("[%s]byte", parts[1])

 	case strings.HasPrefix(stringKind, "int") || strings.HasPrefix(stringKind, "uint"):
-		parts := regexp.MustCompile("(u)?int([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
-		if len(parts) != 4 {
-			return stringKind
-		}
+		parts := regexp.MustCompile(`(u)?int([0-9]*)`).FindStringSubmatch(stringKind)
 		switch parts[2] {
 		case "8", "16", "32", "64":
-			return fmt.Sprintf("%s%sint%s", parts[3], parts[1], parts[2])
+			return len(parts[0]), fmt.Sprintf("%sint%s", parts[1], parts[2])
 		}
-		return fmt.Sprintf("%s*big.Int", parts[3])
+		return len(parts[0]), "*big.Int"

-	case strings.HasPrefix(stringKind, "bool") || strings.HasPrefix(stringKind, "string"):
-		parts := regexp.MustCompile("([a-z]+)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
-		if len(parts) != 3 {
-			return stringKind
-		}
-		return fmt.Sprintf("%s%s", parts[2], parts[1])
+	case strings.HasPrefix(stringKind, "bool"):
+		return len("bool"), "bool"
+
+	case strings.HasPrefix(stringKind, "string"):
+		return len("string"), "string"

 	default:
-		return stringKind
+		return len(stringKind), stringKind
 	}
 }

+// Translates the array sizes to a Java declaration of a (nested) array of the inner type.
+// Simply returns the inner type if arraySizes is empty.
+func arrayBindingJava(inner string, arraySizes []string) string {
+	// Java array type declarations do not include the length.
+	return inner + strings.Repeat("[]", len(arraySizes))
+}
+
 // bindTypeJava converts a Solidity type to a Java one. Since there is no clear mapping
 // from all Solidity types to Java ones (e.g. uint17), those that cannot be exactly
 // mapped will use an upscaled type (e.g. BigDecimal).
 func bindTypeJava(kind abi.Type) string {
 	stringKind := kind.String()
+	innerLen, innerMapping := bindUnnestedTypeJava(stringKind)
+	return arrayBindingJava(wrapArray(stringKind, innerLen, innerMapping))
+}
+
+// The inner function of bindTypeJava, this finds the inner type of stringKind.
+// (Or just the type itself if it is not an array or slice)
+// The length of the matched part is returned, with the the translated type.
+func bindUnnestedTypeJava(stringKind string) (int, string) {

 	switch {
 	case strings.HasPrefix(stringKind, "address"):
-		parts := regexp.MustCompile("address(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`address(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 2 {
-			return stringKind
+			return len(stringKind), stringKind
 		}
 		if parts[1] == "" {
-			return fmt.Sprintf("Address")
+			return len("address"), "Address"
 		}
-		return fmt.Sprintf("Addresses")
+		return len(parts[0]), "Addresses"

 	case strings.HasPrefix(stringKind, "bytes"):
-		parts := regexp.MustCompile("bytes([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
-		if len(parts) != 3 {
-			return stringKind
+		parts := regexp.MustCompile(`bytes([0-9]*)`).FindStringSubmatch(stringKind)
+		if len(parts) != 2 {
+			return len(stringKind), stringKind
 		}
-		if parts[2] != "" {
-			return "byte[][]"
-		}
-		return "byte[]"
+		return len(parts[0]), "byte[]"

 	case strings.HasPrefix(stringKind, "int") || strings.HasPrefix(stringKind, "uint"):
-		parts := regexp.MustCompile("(u)?int([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
-		if len(parts) != 4 {
-			return stringKind
+		//Note that uint and int (without digits) are also matched,
+		// these are size 256, and will translate to BigInt (the default).
+		parts := regexp.MustCompile(`(u)?int([0-9]*)`).FindStringSubmatch(stringKind)
+		if len(parts) != 3 {
+			return len(stringKind), stringKind
 		}
-		switch parts[2] {
-		case "8", "16", "32", "64":
-			if parts[1] == "" {
-				if parts[3] == "" {
-					return fmt.Sprintf("int%s", parts[2])
-				}
-				return fmt.Sprintf("int%s[]", parts[2])
-			}
+
+		namedSize := map[string]string{
+			"8":  "byte",
+			"16": "short",
+			"32": "int",
+			"64": "long",
+		}[parts[2]]
+
+		//default to BigInt
+		if namedSize == "" {
+			namedSize = "BigInt"
 		}
-		if parts[3] == "" {
-			return fmt.Sprintf("BigInt")
-		}
-		return fmt.Sprintf("BigInts")
+		return len(parts[0]), namedSize

 	case strings.HasPrefix(stringKind, "bool"):
-		parts := regexp.MustCompile("bool(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
-		if len(parts) != 2 {
-			return stringKind
-		}
-		if parts[1] == "" {
-			return fmt.Sprintf("bool")
-		}
-		return fmt.Sprintf("bool[]")
+		return len("bool"), "boolean"

 	case strings.HasPrefix(stringKind, "string"):
-		parts := regexp.MustCompile("string(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
-		if len(parts) != 2 {
-			return stringKind
-		}
-		if parts[1] == "" {
-			return fmt.Sprintf("String")
-		}
-		return fmt.Sprintf("String[]")
+		return len("string"), "String"

 	default:
-		return stringKind
+		return len(stringKind), stringKind
 	}
 }

+// bindTopicType is a set of type binders that convert Solidity types to some
+// supported programming language topic types.
+var bindTopicType = map[Lang]func(kind abi.Type) string{
+	LangGo:   bindTopicTypeGo,
+	LangJava: bindTopicTypeJava,
+}
+
+// bindTypeGo converts a Solidity topic type to a Go one. It is almost the same
+// funcionality as for simple types, but dynamic types get converted to hashes.
+func bindTopicTypeGo(kind abi.Type) string {
+	bound := bindTypeGo(kind)
+	if bound == "string" || bound == "[]byte" {
+		bound = "common.Hash"
+	}
+	return bound
+}
+
+// bindTypeGo converts a Solidity topic type to a Java one. It is almost the same
+// funcionality as for simple types, but dynamic types get converted to hashes.
+func bindTopicTypeJava(kind abi.Type) string {
+	bound := bindTypeJava(kind)
+	if bound == "String" || bound == "Bytes" {
+		bound = "Hash"
+	}
+	return bound
+}
+
 // namedType is a set of functions that transform language specific types to
 // named versions that my be used inside method names.
 var namedType = map[Lang]func(string, abi.Type) string{
@@ -273,12 +354,14 @@ func namedTypeJava(javaKind string, solKind abi.Type) string {
 		return "String"
 	case "string[]":
 		return "Strings"
-	case "bool":
+	case "boolean":
 		return "Bool"
-	case "bool[]":
+	case "boolean[]":
 		return "Bools"
-	case "BigInt":
-		parts := regexp.MustCompile("(u)?int([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(solKind.String())
+	case "BigInt[]":
+		return "BigInts"
+	default:
+		parts := regexp.MustCompile(`(u)?int([0-9]*)(\[[0-9]*\])?`).FindStringSubmatch(solKind.String())
 		if len(parts) != 4 {
 			return javaKind
 		}
@@ -292,8 +375,6 @@ func namedTypeJava(javaKind string, solKind abi.Type) string {
 		default:
 			return javaKind
 		}
-	default:
-		return javaKind
 	}
 }

@@ -304,8 +385,15 @@ var methodNormalizer = map[Lang]func(string) string{
 	LangJava: decapitalise,
 }

-// capitalise makes the first character of a string upper case.
+// capitalise makes the first character of a string upper case, also removing any
+// prefixing underscores from the variable names.
 func capitalise(input string) string {
+	for len(input) > 0 && input[0] == '_' {
+		input = input[1:]
+	}
+	if len(input) == 0 {
+		return ""
+	}
 	return strings.ToUpper(input[:1]) + input[1:]
 }

@@ -314,16 +402,25 @@ func decapitalise(input string) string {
 	return strings.ToLower(input[:1]) + input[1:]
 }

-// structured checks whether a method has enough information to return a proper
-// Go struct ot if flat returns are needed.
-func structured(method abi.Method) bool {
-	if len(method.Outputs) < 2 {
+// structured checks whether a list of ABI data types has enough information to
+// operate through a proper Go struct or if flat returns are needed.
+func structured(args abi.Arguments) bool {
+	if len(args) < 2 {
 		return false
 	}
-	for _, out := range method.Outputs {
+	exists := make(map[string]bool)
+	for _, out := range args {
+		// If the name is anonymous, we can't organize into a struct
 		if out.Name == "" {
 			return false
 		}
+		// If the field name is empty when normalized or collides (var, Var, _var, _Var),
+		// we can't organize into a struct
+		field := capitalise(out.Name)
+		if field == "" || exists[field] {
+			return false
+		}
+		exists[field] = true
 	}
 	return true
 }
--- a/accounts/abi/bind/bind_test.go
+++ b/accounts/abi/bind/bind_test.go
@@ -126,6 +126,7 @@ var bindTests = []struct {
 				{"type":"function","name":"namedOutput","constant":true,"inputs":[],"outputs":[{"name":"str","type":"string"}]},
 				{"type":"function","name":"anonOutput","constant":true,"inputs":[],"outputs":[{"name":"","type":"string"}]},
 				{"type":"function","name":"namedOutputs","constant":true,"inputs":[],"outputs":[{"name":"str1","type":"string"},{"name":"str2","type":"string"}]},
+				{"type":"function","name":"collidingOutputs","constant":true,"inputs":[],"outputs":[{"name":"str","type":"string"},{"name":"Str","type":"string"}]},
 				{"type":"function","name":"anonOutputs","constant":true,"inputs":[],"outputs":[{"name":"","type":"string"},{"name":"","type":"string"}]},
 				{"type":"function","name":"mixedOutputs","constant":true,"inputs":[],"outputs":[{"name":"","type":"string"},{"name":"str","type":"string"}]}
 			]
@@ -140,12 +141,71 @@ var bindTests = []struct {
 			 str1, err        = b.NamedOutput(nil)
 			 str1, err        = b.AnonOutput(nil)
 			 res, _          := b.NamedOutputs(nil)
+			 str1, str2, err  = b.CollidingOutputs(nil)
 			 str1, str2, err  = b.AnonOutputs(nil)
 			 str1, str2, err  = b.MixedOutputs(nil)

 			 fmt.Println(str1, str2, res.Str1, res.Str2, err)
 		 }`,
 	},
+	// Tests that named, anonymous and indexed events are handled correctly
+	{
+		`EventChecker`, ``, ``,
+		`
+			[
+				{"type":"event","name":"empty","inputs":[]},
+				{"type":"event","name":"indexed","inputs":[{"name":"addr","type":"address","indexed":true},{"name":"num","type":"int256","indexed":true}]},
+				{"type":"event","name":"mixed","inputs":[{"name":"addr","type":"address","indexed":true},{"name":"num","type":"int256"}]},
+				{"type":"event","name":"anonymous","anonymous":true,"inputs":[]},
+				{"type":"event","name":"dynamic","inputs":[{"name":"idxStr","type":"string","indexed":true},{"name":"idxDat","type":"bytes","indexed":true},{"name":"str","type":"string"},{"name":"dat","type":"bytes"}]}
+			]
+		`,
+		`if e, err := NewEventChecker(common.Address{}, nil); e == nil || err != nil {
+			 t.Fatalf("binding (%v) nil or error (%v) not nil", e, nil)
+		 } else if false { // Don't run, just compile and test types
+			 var (
+				 err  error
+			   res  bool
+				 str  string
+				 dat  []byte
+				 hash common.Hash
+			 )
+			 _, err = e.FilterEmpty(nil)
+			 _, err = e.FilterIndexed(nil, []common.Address{}, []*big.Int{})
+
+			 mit, err := e.FilterMixed(nil, []common.Address{})
+
+			 res = mit.Next()  // Make sure the iterator has a Next method
+			 err = mit.Error() // Make sure the iterator has an Error method
+			 err = mit.Close() // Make sure the iterator has a Close method
+
+			 fmt.Println(mit.Event.Raw.BlockHash) // Make sure the raw log is contained within the results
+			 fmt.Println(mit.Event.Num)           // Make sure the unpacked non-indexed fields are present
+			 fmt.Println(mit.Event.Addr)          // Make sure the reconstructed indexed fields are present
+
+			 dit, err := e.FilterDynamic(nil, []string{}, [][]byte{})
+
+			 str  = dit.Event.Str    // Make sure non-indexed strings retain their type
+			 dat  = dit.Event.Dat    // Make sure non-indexed bytes retain their type
+			 hash = dit.Event.IdxStr // Make sure indexed strings turn into hashes
+			 hash = dit.Event.IdxDat // Make sure indexed bytes turn into hashes
+
+			 sink := make(chan *EventCheckerMixed)
+			 sub, err := e.WatchMixed(nil, sink, []common.Address{})
+			 defer sub.Unsubscribe()
+
+			 event := <-sink
+			 fmt.Println(event.Raw.BlockHash) // Make sure the raw log is contained within the results
+			 fmt.Println(event.Num)           // Make sure the unpacked non-indexed fields are present
+			 fmt.Println(event.Addr)          // Make sure the reconstructed indexed fields are present
+
+			 fmt.Println(res, str, dat, hash, err)
+		 }
+		 // Run a tiny reflection test to ensure disallowed methods don't appear
+		 if _, ok := reflect.TypeOf(&EventChecker{}).MethodByName("FilterAnonymous"); ok {
+		 	t.Errorf("binding has disallowed method (FilterAnonymous)")
+		 }`,
+	},
 	// Test that contract interactions (deploy, transact and call) generate working code
 	{
 		`Interactor`,
@@ -169,7 +229,7 @@ var bindTests = []struct {
 			// Generate a new random account and a funded simulator
 			key, _ := crypto.GenerateKey()
 			auth := bind.NewKeyedTransactor(key)
-			sim := backends.NewSimulatedBackend(core.GenesisAccount{Address: auth.From, Balance: big.NewInt(10000000000)})
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})

 			// Deploy an interaction tester contract and call a transaction on it
 			_, _, interactor, err := DeployInteractor(auth, sim, "Deploy string")
@@ -210,7 +270,7 @@ var bindTests = []struct {
 			// Generate a new random account and a funded simulator
 			key, _ := crypto.GenerateKey()
 			auth := bind.NewKeyedTransactor(key)
-			sim := backends.NewSimulatedBackend(core.GenesisAccount{Address: auth.From, Balance: big.NewInt(10000000000)})
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})

 			// Deploy a tuple tester contract and execute a structured call on it
 			_, _, getter, err := DeployGetter(auth, sim)
@@ -242,7 +302,7 @@ var bindTests = []struct {
 			// Generate a new random account and a funded simulator
 			key, _ := crypto.GenerateKey()
 			auth := bind.NewKeyedTransactor(key)
-			sim := backends.NewSimulatedBackend(core.GenesisAccount{Address: auth.From, Balance: big.NewInt(10000000000)})
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})

 			// Deploy a tuple tester contract and execute a structured call on it
 			_, _, tupler, err := DeployTupler(auth, sim)
@@ -284,7 +344,7 @@ var bindTests = []struct {
 			// Generate a new random account and a funded simulator
 			key, _ := crypto.GenerateKey()
 			auth := bind.NewKeyedTransactor(key)
-			sim := backends.NewSimulatedBackend(core.GenesisAccount{Address: auth.From, Balance: big.NewInt(10000000000)})
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})

 			// Deploy a slice tester contract and execute a n array call on it
 			_, _, slicer, err := DeploySlicer(auth, sim)
@@ -318,7 +378,7 @@ var bindTests = []struct {
 			// Generate a new random account and a funded simulator
 			key, _ := crypto.GenerateKey()
 			auth := bind.NewKeyedTransactor(key)
-			sim := backends.NewSimulatedBackend(core.GenesisAccount{Address: auth.From, Balance: big.NewInt(10000000000)})
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})

 			// Deploy a default method invoker contract and execute its default method
 			_, _, defaulter, err := DeployDefaulter(auth, sim)
@@ -341,17 +401,17 @@ var bindTests = []struct {
 	{
 		`NonExistent`,
 		`
-		contract NonExistent {
-			function String() constant returns(string) {
-				return "I don't exist";
+			contract NonExistent {
+				function String() constant returns(string) {
+					return "I don't exist";
+				}
 			}
-		}
 		`,
 		`6060604052609f8060106000396000f3606060405260e060020a6000350463f97a60058114601a575b005b600060605260c0604052600d60809081527f4920646f6e27742065786973740000000000000000000000000000000000000060a052602060c0908152600d60e081905281906101009060a09080838184600060046012f15050815172ffffffffffffffffffffffffffffffffffffff1916909152505060405161012081900392509050f3`,
 		`[{"constant":true,"inputs":[],"name":"String","outputs":[{"name":"","type":"string"}],"type":"function"}]`,
 		`
 			// Create a simulator and wrap a non-deployed contract
-			sim := backends.NewSimulatedBackend()
+			sim := backends.NewSimulatedBackend(nil)

 			nonexistent, err := NewNonExistent(common.Address{}, sim)
 			if err != nil {
@@ -365,6 +425,384 @@ var bindTests = []struct {
 			}
 		`,
 	},
+	// Tests that gas estimation works for contracts with	weird gas mechanics too.
+	{
+		`FunkyGasPattern`,
+		`
+			contract FunkyGasPattern {
+				string public field;
+
+				function SetField(string value) {
+					// This check will screw gas estimation! Good, good!
+					if (msg.gas < 100000) {
+						throw;
+					}
+					field = value;
+				}
+			}
+		`,
+		`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`,
+		`[{"constant":false,"inputs":[{"name":"value","type":"string"}],"name":"SetField","outputs":[],"type":"function"},{"constant":true,"inputs":[],"name":"field","outputs":[{"name":"","type":"string"}],"type":"function"}]`,
+		`
+			// Generate a new random account and a funded simulator
+			key, _ := crypto.GenerateKey()
+			auth := bind.NewKeyedTransactor(key)
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})
+
+			// Deploy a funky gas pattern contract
+			_, _, limiter, err := DeployFunkyGasPattern(auth, sim)
+			if err != nil {
+				t.Fatalf("Failed to deploy funky contract: %v", err)
+			}
+			sim.Commit()
+
+			// Set the field with automatic estimation and check that it succeeds
+			if _, err := limiter.SetField(auth, "automatic"); err != nil {
+				t.Fatalf("Failed to call automatically gased transaction: %v", err)
+			}
+			sim.Commit()
+
+			if field, _ := limiter.Field(nil); field != "automatic" {
+				t.Fatalf("Field mismatch: have %v, want %v", field, "automatic")
+			}
+		`,
+	},
+	// Test that constant functions can be called from an (optional) specified address
+	{
+		`CallFrom`,
+		`
+			contract CallFrom {
+				function callFrom() constant returns(address) {
+					return msg.sender;
+				}
+			}
+		`, `6060604052346000575b6086806100176000396000f300606060405263ffffffff60e060020a60003504166349f8e98281146022575b6000565b34600057602c6055565b6040805173ffffffffffffffffffffffffffffffffffffffff9092168252519081900360200190f35b335b905600a165627a7a72305820aef6b7685c0fa24ba6027e4870404a57df701473fe4107741805c19f5138417c0029`,
+		`[{"constant":true,"inputs":[],"name":"callFrom","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"}]`,
+		`
+			// Generate a new random account and a funded simulator
+			key, _ := crypto.GenerateKey()
+			auth := bind.NewKeyedTransactor(key)
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})
+
+			// Deploy a sender tester contract and execute a structured call on it
+			_, _, callfrom, err := DeployCallFrom(auth, sim)
+			if err != nil {
+				t.Fatalf("Failed to deploy sender contract: %v", err)
+			}
+			sim.Commit()
+
+			if res, err := callfrom.CallFrom(nil); err != nil {
+				t.Errorf("Failed to call constant function: %v", err)
+			} else if res != (common.Address{}) {
+				t.Errorf("Invalid address returned, want: %x, got: %x", (common.Address{}), res)
+			}
+
+			for _, addr := range []common.Address{common.Address{}, common.Address{1}, common.Address{2}} {
+				if res, err := callfrom.CallFrom(&bind.CallOpts{From: addr}); err != nil {
+					t.Fatalf("Failed to call constant function: %v", err)
+				} else if res != addr {
+					t.Fatalf("Invalid address returned, want: %x, got: %x", addr, res)
+				}
+			}
+		`,
+	},
+	{
+		`Underscorer`,
+		`
+		contract Underscorer {
+			function UnderscoredOutput() constant returns (int _int, string _string) {
+				return (314, "pi");
+			}
+			function LowerLowerCollision() constant returns (int _res, int res) {
+				return (1, 2);
+			}
+			function LowerUpperCollision() constant returns (int _res, int Res) {
+				return (1, 2);
+		  }
+			function UpperLowerCollision() constant returns (int _Res, int res) {
+				return (1, 2);
+			}
+			function UpperUpperCollision() constant returns (int _Res, int Res) {
+				return (1, 2);
+			}
+			function PurelyUnderscoredOutput() constant returns (int _, int res) {
+				return (1, 2);
+			}
+			function AllPurelyUnderscoredOutput() constant returns (int _, int __) {
+				return (1, 2);
+			}
+		}
+		`, `6060604052341561000f57600080fd5b6103498061001e6000396000f300606060405260043610610083576000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff16806303a592131461008857806367e6633d146100b85780639df484851461014d578063af7486ab1461017d578063b564b34d146101ad578063e02ab24d146101dd578063e409ca451461020d575b600080fd5b341561009357600080fd5b61009b61023d565b604051808381526020018281526020019250505060405180910390f35b34156100c357600080fd5b6100cb610252565b6040518083815260200180602001828103825283818151815260200191508051906020019080838360005b838110156101115780820151818401526020810190506100f6565b50505050905090810190601f16801561013e5780820380516001836020036101000a031916815260200191505b50935050505060405180910390f35b341561015857600080fd5b6101606102a0565b604051808381526020018281526020019250505060405180910390f35b341561018857600080fd5b6101906102b5565b604051808381526020018281526020019250505060405180910390f35b34156101b857600080fd5b6101c06102ca565b604051808381526020018281526020019250505060405180910390f35b34156101e857600080fd5b6101f06102df565b604051808381526020018281526020019250505060405180910390f35b341561021857600080fd5b6102206102f4565b604051808381526020018281526020019250505060405180910390f35b60008060016002819150809050915091509091565b600061025c610309565b61013a8090506040805190810160405280600281526020017f7069000000000000000000000000000000000000000000000000000000000000815250915091509091565b60008060016002819150809050915091509091565b60008060016002819150809050915091509091565b60008060016002819150809050915091509091565b60008060016002819150809050915091509091565b60008060016002819150809050915091509091565b6020604051908101604052806000815250905600a165627a7a72305820c11dcfa136fc7d182ee4d34f0b12d988496228f7e2d02d2b5376d996ca1743d00029`,
+		`[{"constant":true,"inputs":[],"name":"LowerUpperCollision","outputs":[{"name":"_res","type":"int256"},{"name":"Res","type":"int256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"UnderscoredOutput","outputs":[{"name":"_int","type":"int256"},{"name":"_string","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"PurelyUnderscoredOutput","outputs":[{"name":"_","type":"int256"},{"name":"res","type":"int256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"UpperLowerCollision","outputs":[{"name":"_Res","type":"int256"},{"name":"res","type":"int256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"AllPurelyUnderscoredOutput","outputs":[{"name":"_","type":"int256"},{"name":"__","type":"int256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"UpperUpperCollision","outputs":[{"name":"_Res","type":"int256"},{"name":"Res","type":"int256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"LowerLowerCollision","outputs":[{"name":"_res","type":"int256"},{"name":"res","type":"int256"}],"payable":false,"stateMutability":"view","type":"function"}]`,
+		`
+			// Generate a new random account and a funded simulator
+			key, _ := crypto.GenerateKey()
+			auth := bind.NewKeyedTransactor(key)
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})
+
+			// Deploy a underscorer tester contract and execute a structured call on it
+			_, _, underscorer, err := DeployUnderscorer(auth, sim)
+			if err != nil {
+				t.Fatalf("Failed to deploy underscorer contract: %v", err)
+			}
+			sim.Commit()
+
+			// Verify that underscored return values correctly parse into structs
+			if res, err := underscorer.UnderscoredOutput(nil); err != nil {
+				t.Errorf("Failed to call constant function: %v", err)
+			} else if res.Int.Cmp(big.NewInt(314)) != 0 || res.String != "pi" {
+				t.Errorf("Invalid result, want: {314, \"pi\"}, got: %+v", res)
+			}
+			// Verify that underscored and non-underscored name collisions force tuple outputs
+			var a, b *big.Int
+
+			a, b, _ = underscorer.LowerLowerCollision(nil)
+			a, b, _ = underscorer.LowerUpperCollision(nil)
+			a, b, _ = underscorer.UpperLowerCollision(nil)
+			a, b, _ = underscorer.UpperUpperCollision(nil)
+			a, b, _ = underscorer.PurelyUnderscoredOutput(nil)
+			a, b, _ = underscorer.AllPurelyUnderscoredOutput(nil)
+
+			fmt.Println(a, b, err)
+		`,
+	},
+	// Tests that logs can be successfully filtered and decoded.
+	{
+		`Eventer`,
+		`
+			contract Eventer {
+					event SimpleEvent (
+					address indexed Addr,
+					bytes32 indexed Id,
+					bool    indexed Flag,
+					uint    Value
+				);
+				function raiseSimpleEvent(address addr, bytes32 id, bool flag, uint value) {
+					SimpleEvent(addr, id, flag, value);
+				}
+
+				event NodataEvent (
+					uint   indexed Number,
+					int16  indexed Short,
+					uint32 indexed Long
+				);
+				function raiseNodataEvent(uint number, int16 short, uint32 long) {
+					NodataEvent(number, short, long);
+				}
+
+				event DynamicEvent (
+					string indexed IndexedString,
+					bytes  indexed IndexedBytes,
+					string NonIndexedString,
+					bytes  NonIndexedBytes
+				);
+				function raiseDynamicEvent(string str, bytes blob) {
+					DynamicEvent(str, blob, str, blob);
+				}
+			}
+		`,
+		`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`,
+		`[{"constant":false,"inputs":[{"name":"str","type":"string"},{"name":"blob","type":"bytes"}],"name":"raiseDynamicEvent","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":false,"inputs":[{"name":"addr","type":"address"},{"name":"id","type":"bytes32"},{"name":"flag","type":"bool"},{"name":"value","type":"uint256"}],"name":"raiseSimpleEvent","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":false,"inputs":[{"name":"number","type":"uint256"},{"name":"short","type":"int16"},{"name":"long","type":"uint32"}],"name":"raiseNodataEvent","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"anonymous":false,"inputs":[{"indexed":true,"name":"Addr","type":"address"},{"indexed":true,"name":"Id","type":"bytes32"},{"indexed":true,"name":"Flag","type":"bool"},{"indexed":false,"name":"Value","type":"uint256"}],"name":"SimpleEvent","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"Number","type":"uint256"},{"indexed":true,"name":"Short","type":"int16"},{"indexed":true,"name":"Long","type":"uint32"}],"name":"NodataEvent","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"IndexedString","type":"string"},{"indexed":true,"name":"IndexedBytes","type":"bytes"},{"indexed":false,"name":"NonIndexedString","type":"string"},{"indexed":false,"name":"NonIndexedBytes","type":"bytes"}],"name":"DynamicEvent","type":"event"}]`,
+		`
+			// Generate a new random account and a funded simulator
+			key, _ := crypto.GenerateKey()
+			auth := bind.NewKeyedTransactor(key)
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})
+
+			// Deploy an eventer contract
+			_, _, eventer, err := DeployEventer(auth, sim)
+			if err != nil {
+				t.Fatalf("Failed to deploy eventer contract: %v", err)
+			}
+			sim.Commit()
+
+			// Inject a few events into the contract, gradually more in each block
+			for i := 1; i <= 3; i++ {
+				for j := 1; j <= i; j++ {
+					if _, err := eventer.RaiseSimpleEvent(auth, common.Address{byte(j)}, [32]byte{byte(j)}, true, big.NewInt(int64(10*i+j))); err != nil {
+						t.Fatalf("block %d, event %d: raise failed: %v", i, j, err)
+					}
+				}
+				sim.Commit()
+			}
+			// Test filtering for certain events and ensure they can be found
+			sit, err := eventer.FilterSimpleEvent(nil, []common.Address{common.Address{1}, common.Address{3}}, [][32]byte{{byte(1)}, {byte(2)}, {byte(3)}}, []bool{true})
+			if err != nil {
+				t.Fatalf("failed to filter for simple events: %v", err)
+			}
+			defer sit.Close()
+
+			sit.Next()
+			if sit.Event.Value.Uint64() != 11 || !sit.Event.Flag {
+				t.Errorf("simple log content mismatch: have %v, want {11, true}", sit.Event)
+			}
+			sit.Next()
+			if sit.Event.Value.Uint64() != 21 || !sit.Event.Flag {
+				t.Errorf("simple log content mismatch: have %v, want {21, true}", sit.Event)
+			}
+			sit.Next()
+			if sit.Event.Value.Uint64() != 31 || !sit.Event.Flag {
+				t.Errorf("simple log content mismatch: have %v, want {31, true}", sit.Event)
+			}
+			sit.Next()
+			if sit.Event.Value.Uint64() != 33 || !sit.Event.Flag {
+				t.Errorf("simple log content mismatch: have %v, want {33, true}", sit.Event)
+			}
+
+			if sit.Next() {
+				t.Errorf("unexpected simple event found: %+v", sit.Event)
+			}
+			if err = sit.Error(); err != nil {
+				t.Fatalf("simple event iteration failed: %v", err)
+			}
+			// Test raising and filtering for an event with no data component
+			if _, err := eventer.RaiseNodataEvent(auth, big.NewInt(314), 141, 271); err != nil {
+				t.Fatalf("failed to raise nodata event: %v", err)
+			}
+			sim.Commit()
+
+			nit, err := eventer.FilterNodataEvent(nil, []*big.Int{big.NewInt(314)}, []int16{140, 141, 142}, []uint32{271})
+			if err != nil {
+				t.Fatalf("failed to filter for nodata events: %v", err)
+			}
+			defer nit.Close()
+
+			if !nit.Next() {
+				t.Fatalf("nodata log not found: %v", nit.Error())
+			}
+			if nit.Event.Number.Uint64() != 314 {
+				t.Errorf("nodata log content mismatch: have %v, want 314", nit.Event.Number)
+			}
+			if nit.Next() {
+				t.Errorf("unexpected nodata event found: %+v", nit.Event)
+			}
+			if err = nit.Error(); err != nil {
+				t.Fatalf("nodata event iteration failed: %v", err)
+			}
+			// Test raising and filtering for events with dynamic indexed components
+			if _, err := eventer.RaiseDynamicEvent(auth, "Hello", []byte("World")); err != nil {
+				t.Fatalf("failed to raise dynamic event: %v", err)
+			}
+			sim.Commit()
+
+			dit, err := eventer.FilterDynamicEvent(nil, []string{"Hi", "Hello", "Bye"}, [][]byte{[]byte("World")})
+			if err != nil {
+				t.Fatalf("failed to filter for dynamic events: %v", err)
+			}
+			defer dit.Close()
+
+			if !dit.Next() {
+				t.Fatalf("dynamic log not found: %v", dit.Error())
+			}
+			if dit.Event.NonIndexedString != "Hello" || string(dit.Event.NonIndexedBytes) != "World" ||	dit.Event.IndexedString != common.HexToHash("0x06b3dfaec148fb1bb2b066f10ec285e7c9bf402ab32aa78a5d38e34566810cd2") || dit.Event.IndexedBytes != common.HexToHash("0xf2208c967df089f60420785795c0a9ba8896b0f6f1867fa7f1f12ad6f79c1a18") {
+				t.Errorf("dynamic log content mismatch: have %v, want {'0x06b3dfaec148fb1bb2b066f10ec285e7c9bf402ab32aa78a5d38e34566810cd2, '0xf2208c967df089f60420785795c0a9ba8896b0f6f1867fa7f1f12ad6f79c1a18', 'Hello', 'World'}", dit.Event)
+			}
+			if dit.Next() {
+				t.Errorf("unexpected dynamic event found: %+v", dit.Event)
+			}
+			if err = dit.Error(); err != nil {
+				t.Fatalf("dynamic event iteration failed: %v", err)
+			}
+			// Test subscribing to an event and raising it afterwards
+			ch := make(chan *EventerSimpleEvent, 16)
+			sub, err := eventer.WatchSimpleEvent(nil, ch, nil, nil, nil)
+			if err != nil {
+				t.Fatalf("failed to subscribe to simple events: %v", err)
+			}
+			if _, err := eventer.RaiseSimpleEvent(auth, common.Address{255}, [32]byte{255}, true, big.NewInt(255)); err != nil {
+				t.Fatalf("failed to raise subscribed simple event: %v", err)
+			}
+			sim.Commit()
+
+			select {
+			case event := <-ch:
+				if event.Value.Uint64() != 255 {
+					t.Errorf("simple log content mismatch: have %v, want 255", event)
+				}
+			case <-time.After(250 * time.Millisecond):
+				t.Fatalf("subscribed simple event didn't arrive")
+			}
+			// Unsubscribe from the event and make sure we're not delivered more
+			sub.Unsubscribe()
+
+			if _, err := eventer.RaiseSimpleEvent(auth, common.Address{254}, [32]byte{254}, true, big.NewInt(254)); err != nil {
+				t.Fatalf("failed to raise subscribed simple event: %v", err)
+			}
+			sim.Commit()
+
+			select {
+			case event := <-ch:
+				t.Fatalf("unsubscribed simple event arrived: %v", event)
+			case <-time.After(250 * time.Millisecond):
+			}
+		`,
+	},
+	{
+		`DeeplyNestedArray`,
+		`
+			contract DeeplyNestedArray {
+				uint64[3][4][5] public deepUint64Array;
+				function storeDeepUintArray(uint64[3][4][5] arr) public {
+					deepUint64Array = arr;
+				}
+				function retrieveDeepArray() public view returns (uint64[3][4][5]) {
+					return deepUint64Array;
+				}
+			}
+		`,
+		`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`,
+		`[{"constant":false,"inputs":[{"name":"arr","type":"uint64[3][4][5]"}],"name":"storeDeepUintArray","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"retrieveDeepArray","outputs":[{"name":"","type":"uint64[3][4][5]"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"name":"","type":"uint256"},{"name":"","type":"uint256"},{"name":"","type":"uint256"}],"name":"deepUint64Array","outputs":[{"name":"","type":"uint64"}],"payable":false,"stateMutability":"view","type":"function"}]`,
+		`
+			// Generate a new random account and a funded simulator
+			key, _ := crypto.GenerateKey()
+			auth := bind.NewKeyedTransactor(key)
+			sim := backends.NewSimulatedBackend(core.GenesisAlloc{auth.From: {Balance: big.NewInt(10000000000)}})
+
+			//deploy the test contract
+			_, _, testContract, err := DeployDeeplyNestedArray(auth, sim)
+			if err != nil {
+				t.Fatalf("Failed to deploy test contract: %v", err)
+			}
+
+			// Finish deploy.
+			sim.Commit()
+
+			//Create coordinate-filled array, for testing purposes.
+			testArr := [5][4][3]uint64{}
+			for i := 0; i < 5; i++ {
+				testArr[i] = [4][3]uint64{}
+				for j := 0; j < 4; j++ {
+					testArr[i][j] = [3]uint64{}
+					for k := 0; k < 3; k++ {
+						//pack the coordinates, each array value will be unique, and can be validated easily.
+						testArr[i][j][k] = uint64(i) << 16 | uint64(j) << 8 | uint64(k)
+					}
+				}
+			}
+
+			if _, err := testContract.StoreDeepUintArray(&bind.TransactOpts{
+				From: auth.From,
+				Signer: auth.Signer,
+			}, testArr); err != nil {
+				t.Fatalf("Failed to store nested array in test contract: %v", err)
+			}
+
+			sim.Commit()
+
+			retrievedArr, err := testContract.RetrieveDeepArray(&bind.CallOpts{
+				From: auth.From,
+				Pending: false,
+			})
+			if err != nil {
+				t.Fatalf("Failed to retrieve nested array from test contract: %v", err)
+			}
+
+			//quick check to see if contents were copied
+			// (See accounts/abi/unpack_test.go for more extensive testing)
+			if retrievedArr[4][3][2] != testArr[4][3][2] {
+				t.Fatalf("Retrieved value does not match expected value! got: %d, expected: %d. %v", retrievedArr[4][3][2], testArr[4][3][2], err)
+			}`,
+	},
 }

 // Tests that packages generated by the binder can be successfully compiled and
@@ -376,8 +814,8 @@ func TestBindings(t *testing.T) {
 		t.Skip("go sdk not found for testing")
 	}
 	// Skip the test if the go-ethereum sources are symlinked (https://github.com/golang/go/issues/14845)
-	linkTestCode := fmt.Sprintf("package linktest\nfunc CheckSymlinks(){\nfmt.Println(backends.NewSimulatedBackend())\n}")
-	linkTestDeps, err := imports.Process("", []byte(linkTestCode), nil)
+	linkTestCode := fmt.Sprintf("package linktest\nfunc CheckSymlinks(){\nfmt.Println(backends.NewSimulatedBackend(nil))\n}")
+	linkTestDeps, err := imports.Process(os.TempDir(), []byte(linkTestCode), nil)
 	if err != nil {
 		t.Fatalf("failed check for goimports symlink bug: %v", err)
 	}
@@ -416,7 +854,7 @@ func TestBindings(t *testing.T) {
 		}
 	}
 	// Test the entire package and report any failures
-	cmd := exec.Command(gocmd, "test", "-v")
+	cmd := exec.Command(gocmd, "test", "-v", "-count", "1")
 	cmd.Dir = pkg
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Fatalf("failed to run binding test: %v\n%s", err, out)
--- a/accounts/abi/bind/template.go
+++ b/accounts/abi/bind/template.go
@@ -32,6 +32,7 @@ type tmplContract struct {
 	Constructor abi.Method             // Contract constructor for deploy parametrization
 	Calls       map[string]*tmplMethod // Contract calls that only read state data
 	Transacts   map[string]*tmplMethod // Contract calls that write state data
+	Events      map[string]*tmplEvent  // Contract events accessors
 }

 // tmplMethod is a wrapper around an abi.Method that contains a few preprocessed
@@ -39,7 +40,13 @@ type tmplContract struct {
 type tmplMethod struct {
 	Original   abi.Method // Original method as parsed by the abi package
 	Normalized abi.Method // Normalized version of the parsed method (capitalized names, non-anonymous args/returns)
-	Structured bool       // Whether the returns should be accumulated into a contract
+	Structured bool       // Whether the returns should be accumulated into a struct
+}
+
+// tmplEvent is a wrapper around an a
+type tmplEvent struct {
+	Original   abi.Event // Original event as parsed by the abi package
+	Normalized abi.Event // Normalized version of the parsed fields
 }

 // tmplSource is language to template mapping containing all the supported
@@ -52,8 +59,8 @@ var tmplSource = map[Lang]string{
 // tmplSourceGo is the Go source template use to generate the contract binding
 // based on.
 const tmplSourceGo = `
-// This file is an automatically generated Go binding. Do not modify as any
-// change will likely be lost upon the next re-generation!
+// Code generated - DO NOT EDIT.
+// This file is a generated binding and any manual changes will be lost.

 package {{.Package}}

@@ -75,7 +82,7 @@ package {{.Package}}
 		  if err != nil {
 		    return common.Address{}, nil, nil, err
 		  }
-		  return address, tx, &{{.Type}}{ {{.Type}}Caller: {{.Type}}Caller{contract: contract}, {{.Type}}Transactor: {{.Type}}Transactor{contract: contract} }, nil
+		  return address, tx, &{{.Type}}{ {{.Type}}Caller: {{.Type}}Caller{contract: contract}, {{.Type}}Transactor: {{.Type}}Transactor{contract: contract}, {{.Type}}Filterer: {{.Type}}Filterer{contract: contract} }, nil
 		}
 	{{end}}

@@ -83,6 +90,7 @@ package {{.Package}}
 	type {{.Type}} struct {
 	  {{.Type}}Caller     // Read-only binding to the contract
 	  {{.Type}}Transactor // Write-only binding to the contract
+		{{.Type}}Filterer   // Log filterer for contract events
 	}

 	// {{.Type}}Caller is an auto generated read-only Go binding around an Ethereum contract.
@@ -95,6 +103,11 @@ package {{.Package}}
 	  contract *bind.BoundContract // Generic contract wrapper for the low level calls
 	}

+	// {{.Type}}Filterer is an auto generated log filtering Go binding around an Ethereum contract events.
+	type {{.Type}}Filterer struct {
+	  contract *bind.BoundContract // Generic contract wrapper for the low level calls
+	}
+
 	// {{.Type}}Session is an auto generated Go binding around an Ethereum contract,
 	// with pre-set call and transact options.
 	type {{.Type}}Session struct {
@@ -134,16 +147,16 @@ package {{.Package}}

 	// New{{.Type}} creates a new instance of {{.Type}}, bound to a specific deployed contract.
 	func New{{.Type}}(address common.Address, backend bind.ContractBackend) (*{{.Type}}, error) {
-	  contract, err := bind{{.Type}}(address, backend, backend)
+	  contract, err := bind{{.Type}}(address, backend, backend, backend)
 	  if err != nil {
 	    return nil, err
 	  }
-	  return &{{.Type}}{ {{.Type}}Caller: {{.Type}}Caller{contract: contract}, {{.Type}}Transactor: {{.Type}}Transactor{contract: contract} }, nil
+	  return &{{.Type}}{ {{.Type}}Caller: {{.Type}}Caller{contract: contract}, {{.Type}}Transactor: {{.Type}}Transactor{contract: contract}, {{.Type}}Filterer: {{.Type}}Filterer{contract: contract} }, nil
 	}

 	// New{{.Type}}Caller creates a new read-only instance of {{.Type}}, bound to a specific deployed contract.
 	func New{{.Type}}Caller(address common.Address, caller bind.ContractCaller) (*{{.Type}}Caller, error) {
-	  contract, err := bind{{.Type}}(address, caller, nil)
+	  contract, err := bind{{.Type}}(address, caller, nil, nil)
 	  if err != nil {
 	    return nil, err
 	  }
@@ -152,20 +165,29 @@ package {{.Package}}

 	// New{{.Type}}Transactor creates a new write-only instance of {{.Type}}, bound to a specific deployed contract.
 	func New{{.Type}}Transactor(address common.Address, transactor bind.ContractTransactor) (*{{.Type}}Transactor, error) {
-	  contract, err := bind{{.Type}}(address, nil, transactor)
+	  contract, err := bind{{.Type}}(address, nil, transactor, nil)
 	  if err != nil {
 	    return nil, err
 	  }
 	  return &{{.Type}}Transactor{contract: contract}, nil
 	}

+	// New{{.Type}}Filterer creates a new log filterer instance of {{.Type}}, bound to a specific deployed contract.
+ 	func New{{.Type}}Filterer(address common.Address, filterer bind.ContractFilterer) (*{{.Type}}Filterer, error) {
+ 	  contract, err := bind{{.Type}}(address, nil, nil, filterer)
+ 	  if err != nil {
+ 	    return nil, err
+ 	  }
+ 	  return &{{.Type}}Filterer{contract: contract}, nil
+ 	}
+
 	// bind{{.Type}} binds a generic wrapper to an already deployed contract.
-	func bind{{.Type}}(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor) (*bind.BoundContract, error) {
+	func bind{{.Type}}(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor, filterer bind.ContractFilterer) (*bind.BoundContract, error) {
 	  parsed, err := abi.JSON(strings.NewReader({{.Type}}ABI))
 	  if err != nil {
 	    return nil, err
 	  }
-	  return bind.NewBoundContract(address, parsed, caller, transactor), nil
+	  return bind.NewBoundContract(address, parsed, caller, transactor, filterer), nil
 	}

 	// Call invokes the (constant) contract method with params as input values and
@@ -263,6 +285,137 @@ package {{.Package}}
 		  return _{{$contract.Type}}.Contract.{{.Normalized.Name}}(&_{{$contract.Type}}.TransactOpts {{range $i, $_ := .Normalized.Inputs}}, {{.Name}}{{end}})
 		}
 	{{end}}
+
+	{{range .Events}}
+		// {{$contract.Type}}{{.Normalized.Name}}Iterator is returned from Filter{{.Normalized.Name}} and is used to iterate over the raw logs and unpacked data for {{.Normalized.Name}} events raised by the {{$contract.Type}} contract.
+		type {{$contract.Type}}{{.Normalized.Name}}Iterator struct {
+			Event *{{$contract.Type}}{{.Normalized.Name}} // Event containing the contract specifics and raw log
+
+			contract *bind.BoundContract // Generic contract to use for unpacking event data
+			event    string              // Event name to use for unpacking event data
+
+			logs chan types.Log        // Log channel receiving the found contract events
+			sub  ethereum.Subscription // Subscription for errors, completion and termination
+			done bool                  // Whether the subscription completed delivering logs
+			fail error                 // Occurred error to stop iteration
+		}
+		// Next advances the iterator to the subsequent event, returning whether there
+		// are any more events found. In case of a retrieval or parsing error, false is
+		// returned and Error() can be queried for the exact failure.
+		func (it *{{$contract.Type}}{{.Normalized.Name}}Iterator) Next() bool {
+			// If the iterator failed, stop iterating
+			if (it.fail != nil) {
+				return false
+			}
+			// If the iterator completed, deliver directly whatever's available
+			if (it.done) {
+				select {
+				case log := <-it.logs:
+					it.Event = new({{$contract.Type}}{{.Normalized.Name}})
+					if err := it.contract.UnpackLog(it.Event, it.event, log); err != nil {
+						it.fail = err
+						return false
+					}
+					it.Event.Raw = log
+					return true
+
+				default:
+					return false
+				}
+			}
+			// Iterator still in progress, wait for either a data or an error event
+			select {
+			case log := <-it.logs:
+				it.Event = new({{$contract.Type}}{{.Normalized.Name}})
+				if err := it.contract.UnpackLog(it.Event, it.event, log); err != nil {
+					it.fail = err
+					return false
+				}
+				it.Event.Raw = log
+				return true
+
+			case err := <-it.sub.Err():
+				it.done = true
+				it.fail = err
+				return it.Next()
+			}
+		}
+		// Error returns any retrieval or parsing error occurred during filtering.
+		func (it *{{$contract.Type}}{{.Normalized.Name}}Iterator) Error() error {
+			return it.fail
+		}
+		// Close terminates the iteration process, releasing any pending underlying
+		// resources.
+		func (it *{{$contract.Type}}{{.Normalized.Name}}Iterator) Close() error {
+			it.sub.Unsubscribe()
+			return nil
+		}
+
+		// {{$contract.Type}}{{.Normalized.Name}} represents a {{.Normalized.Name}} event raised by the {{$contract.Type}} contract.
+		type {{$contract.Type}}{{.Normalized.Name}} struct { {{range .Normalized.Inputs}}
+			{{capitalise .Name}} {{if .Indexed}}{{bindtopictype .Type}}{{else}}{{bindtype .Type}}{{end}}; {{end}}
+			Raw types.Log // Blockchain specific contextual infos
+		}
+
+		// Filter{{.Normalized.Name}} is a free log retrieval operation binding the contract event 0x{{printf "%x" .Original.Id}}.
+		//
+		// Solidity: {{.Original.String}}
+ 		func (_{{$contract.Type}} *{{$contract.Type}}Filterer) Filter{{.Normalized.Name}}(opts *bind.FilterOpts{{range .Normalized.Inputs}}{{if .Indexed}}, {{.Name}} []{{bindtype .Type}}{{end}}{{end}}) (*{{$contract.Type}}{{.Normalized.Name}}Iterator, error) {
+			{{range .Normalized.Inputs}}
+			{{if .Indexed}}var {{.Name}}Rule []interface{}
+			for _, {{.Name}}Item := range {{.Name}} {
+				{{.Name}}Rule = append({{.Name}}Rule, {{.Name}}Item)
+			}{{end}}{{end}}
+
+			logs, sub, err := _{{$contract.Type}}.contract.FilterLogs(opts, "{{.Original.Name}}"{{range .Normalized.Inputs}}{{if .Indexed}}, {{.Name}}Rule{{end}}{{end}})
+			if err != nil {
+				return nil, err
+			}
+			return &{{$contract.Type}}{{.Normalized.Name}}Iterator{contract: _{{$contract.Type}}.contract, event: "{{.Original.Name}}", logs: logs, sub: sub}, nil
+ 		}
+
+		// Watch{{.Normalized.Name}} is a free log subscription operation binding the contract event 0x{{printf "%x" .Original.Id}}.
+		//
+		// Solidity: {{.Original.String}}
+		func (_{{$contract.Type}} *{{$contract.Type}}Filterer) Watch{{.Normalized.Name}}(opts *bind.WatchOpts, sink chan<- *{{$contract.Type}}{{.Normalized.Name}}{{range .Normalized.Inputs}}{{if .Indexed}}, {{.Name}} []{{bindtype .Type}}{{end}}{{end}}) (event.Subscription, error) {
+			{{range .Normalized.Inputs}}
+			{{if .Indexed}}var {{.Name}}Rule []interface{}
+			for _, {{.Name}}Item := range {{.Name}} {
+				{{.Name}}Rule = append({{.Name}}Rule, {{.Name}}Item)
+			}{{end}}{{end}}
+
+			logs, sub, err := _{{$contract.Type}}.contract.WatchLogs(opts, "{{.Original.Name}}"{{range .Normalized.Inputs}}{{if .Indexed}}, {{.Name}}Rule{{end}}{{end}})
+			if err != nil {
+				return nil, err
+			}
+			return event.NewSubscription(func(quit <-chan struct{}) error {
+				defer sub.Unsubscribe()
+				for {
+					select {
+					case log := <-logs:
+						// New log arrived, parse the event and forward to the user
+						event := new({{$contract.Type}}{{.Normalized.Name}})
+						if err := _{{$contract.Type}}.contract.UnpackLog(event, "{{.Original.Name}}", log); err != nil {
+							return err
+						}
+						event.Raw = log
+
+						select {
+						case sink <- event:
+						case err := <-sub.Err():
+							return err
+						case <-quit:
+							return nil
+						}
+					case err := <-sub.Err():
+						return err
+					case <-quit:
+						return nil
+					}
+				}
+			}), nil
+		}
+ 	{{end}}
 {{end}}
 `

--- a/accounts/abi/bind/topics.go
+++ b/accounts/abi/bind/topics.go
@@ -0,0 +1,189 @@
+// Copyright 2018 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package bind
+
+import (
+	"errors"
+	"fmt"
+	"math/big"
+	"reflect"
+
+	"github.com/ethereum/go-ethereum/accounts/abi"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/crypto"
+)
+
+// makeTopics converts a filter query argument list into a filter topic set.
+func makeTopics(query ...[]interface{}) ([][]common.Hash, error) {
+	topics := make([][]common.Hash, len(query))
+	for i, filter := range query {
+		for _, rule := range filter {
+			var topic common.Hash
+
+			// Try to generate the topic based on simple types
+			switch rule := rule.(type) {
+			case common.Hash:
+				copy(topic[:], rule[:])
+			case common.Address:
+				copy(topic[common.HashLength-common.AddressLength:], rule[:])
+			case *big.Int:
+				blob := rule.Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case bool:
+				if rule {
+					topic[common.HashLength-1] = 1
+				}
+			case int8:
+				blob := big.NewInt(int64(rule)).Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case int16:
+				blob := big.NewInt(int64(rule)).Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case int32:
+				blob := big.NewInt(int64(rule)).Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case int64:
+				blob := big.NewInt(rule).Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case uint8:
+				blob := new(big.Int).SetUint64(uint64(rule)).Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case uint16:
+				blob := new(big.Int).SetUint64(uint64(rule)).Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case uint32:
+				blob := new(big.Int).SetUint64(uint64(rule)).Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case uint64:
+				blob := new(big.Int).SetUint64(rule).Bytes()
+				copy(topic[common.HashLength-len(blob):], blob)
+			case string:
+				hash := crypto.Keccak256Hash([]byte(rule))
+				copy(topic[:], hash[:])
+			case []byte:
+				hash := crypto.Keccak256Hash(rule)
+				copy(topic[:], hash[:])
+
+			default:
+				// Attempt to generate the topic from funky types
+				val := reflect.ValueOf(rule)
+
+				switch {
+				case val.Kind() == reflect.Array && reflect.TypeOf(rule).Elem().Kind() == reflect.Uint8:
+					reflect.Copy(reflect.ValueOf(topic[common.HashLength-val.Len():]), val)
+
+				default:
+					return nil, fmt.Errorf("unsupported indexed type: %T", rule)
+				}
+			}
+			topics[i] = append(topics[i], topic)
+		}
+	}
+	return topics, nil
+}
+
+// Big batch of reflect types for topic reconstruction.
+var (
+	reflectHash    = reflect.TypeOf(common.Hash{})
+	reflectAddress = reflect.TypeOf(common.Address{})
+	reflectBigInt  = reflect.TypeOf(new(big.Int))
+)
+
+// parseTopics converts the indexed topic fields into actual log field values.
+//
+// Note, dynamic types cannot be reconstructed since they get mapped to Keccak256
+// hashes as the topic value!
+func parseTopics(out interface{}, fields abi.Arguments, topics []common.Hash) error {
+	// Sanity check that the fields and topics match up
+	if len(fields) != len(topics) {
+		return errors.New("topic/field count mismatch")
+	}
+	// Iterate over all the fields and reconstruct them from topics
+	for _, arg := range fields {
+		if !arg.Indexed {
+			return errors.New("non-indexed field in topic reconstruction")
+		}
+		field := reflect.ValueOf(out).Elem().FieldByName(capitalise(arg.Name))
+
+		// Try to parse the topic back into the fields based on primitive types
+		switch field.Kind() {
+		case reflect.Bool:
+			if topics[0][common.HashLength-1] == 1 {
+				field.Set(reflect.ValueOf(true))
+			}
+		case reflect.Int8:
+			num := new(big.Int).SetBytes(topics[0][:])
+			field.Set(reflect.ValueOf(int8(num.Int64())))
+
+		case reflect.Int16:
+			num := new(big.Int).SetBytes(topics[0][:])
+			field.Set(reflect.ValueOf(int16(num.Int64())))
+
+		case reflect.Int32:
+			num := new(big.Int).SetBytes(topics[0][:])
+			field.Set(reflect.ValueOf(int32(num.Int64())))
+
+		case reflect.Int64:
+			num := new(big.Int).SetBytes(topics[0][:])
+			field.Set(reflect.ValueOf(num.Int64()))
+
+		case reflect.Uint8:
+			num := new(big.Int).SetBytes(topics[0][:])
+			field.Set(reflect.ValueOf(uint8(num.Uint64())))
+
+		case reflect.Uint16:
+			num := new(big.Int).SetBytes(topics[0][:])
+			field.Set(reflect.ValueOf(uint16(num.Uint64())))
+
+		case reflect.Uint32:
+			num := new(big.Int).SetBytes(topics[0][:])
+			field.Set(reflect.ValueOf(uint32(num.Uint64())))
+
+		case reflect.Uint64:
+			num := new(big.Int).SetBytes(topics[0][:])
+			field.Set(reflect.ValueOf(num.Uint64()))
+
+		default:
+			// Ran out of plain primitive types, try custom types
+			switch field.Type() {
+			case reflectHash: // Also covers all dynamic types
+				field.Set(reflect.ValueOf(topics[0]))
+
+			case reflectAddress:
+				var addr common.Address
+				copy(addr[:], topics[0][common.HashLength-common.AddressLength:])
+				field.Set(reflect.ValueOf(addr))
+
+			case reflectBigInt:
+				num := new(big.Int).SetBytes(topics[0][:])
+				field.Set(reflect.ValueOf(num))
+
+			default:
+				// Ran out of custom types, try the crazies
+				switch {
+				case arg.Type.T == abi.FixedBytesTy:
+					reflect.Copy(field, reflect.ValueOf(topics[0][common.HashLength-arg.Type.Size:]))
+
+				default:
+					return fmt.Errorf("unsupported indexed type: %v", arg.Type)
+				}
+			}
+		}
+		topics = topics[1:]
+	}
+	return nil
+}
--- a/accounts/abi/bind/util.go
+++ b/accounts/abi/bind/util.go
@@ -17,31 +17,31 @@
 package bind

 import (
+	"context"
 	"fmt"
 	"time"

 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/ethereum/go-ethereum/logger"
-	"github.com/ethereum/go-ethereum/logger/glog"
-	"golang.org/x/net/context"
+	"github.com/ethereum/go-ethereum/log"
 )

 // WaitMined waits for tx to be mined on the blockchain.
 // It stops waiting when the context is canceled.
 func WaitMined(ctx context.Context, b DeployBackend, tx *types.Transaction) (*types.Receipt, error) {
-	queryTicker := time.NewTicker(1 * time.Second)
+	queryTicker := time.NewTicker(time.Second)
 	defer queryTicker.Stop()
-	loghash := tx.Hash().Hex()[:8]
+
+	logger := log.New("hash", tx.Hash())
 	for {
 		receipt, err := b.TransactionReceipt(ctx, tx.Hash())
 		if receipt != nil {
 			return receipt, nil
 		}
 		if err != nil {
-			glog.V(logger.Detail).Infof("tx %x error: %v", loghash, err)
+			logger.Trace("Receipt retrieval failed", "err", err)
 		} else {
-			glog.V(logger.Detail).Infof("tx %x not yet mined...", loghash)
+			logger.Trace("Transaction not yet mined")
 		}
 		// Wait for the next round.
 		select {
--- a/accounts/abi/bind/util_test.go
+++ b/accounts/abi/bind/util_test.go
@@ -17,6 +17,7 @@
 package bind_test

 import (
+	"context"
 	"math/big"
 	"testing"
 	"time"
@@ -27,25 +28,24 @@ import (
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
-	"golang.org/x/net/context"
 )

 var testKey, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")

 var waitDeployedTests = map[string]struct {
 	code        string
-	gas         *big.Int
+	gas         uint64
 	wantAddress common.Address
 	wantErr     error
 }{
 	"successful deploy": {
 		code:        `6060604052600a8060106000396000f360606040526008565b00`,
-		gas:         big.NewInt(3000000),
+		gas:         3000000,
 		wantAddress: common.HexToAddress("0x3a220f351252089d385b29beca14e27f204c296a"),
 	},
 	"empty code": {
 		code:        ``,
-		gas:         big.NewInt(300000),
+		gas:         300000,
 		wantErr:     bind.ErrNoCodeAfterDeploy,
 		wantAddress: common.HexToAddress("0x3a220f351252089d385b29beca14e27f204c296a"),
 	},
@@ -53,14 +53,13 @@ var waitDeployedTests = map[string]struct {

 func TestWaitDeployed(t *testing.T) {
 	for name, test := range waitDeployedTests {
-		backend := backends.NewSimulatedBackend(core.GenesisAccount{
-			Address: crypto.PubkeyToAddress(testKey.PublicKey),
-			Balance: big.NewInt(10000000000),
+		backend := backends.NewSimulatedBackend(core.GenesisAlloc{
+			crypto.PubkeyToAddress(testKey.PublicKey): {Balance: big.NewInt(10000000000)},
 		})

 		// Create the transaction.
 		tx := types.NewContractCreation(0, big.NewInt(0), test.gas, big.NewInt(1), common.FromHex(test.code))
-		tx, _ = tx.SignECDSA(types.HomesteadSigner{}, testKey)
+		tx, _ = types.SignTx(tx, types.HomesteadSigner{}, testKey)

 		// Wait for it to get mined in the background.
 		var (
--- a/accounts/abi/error.go
+++ b/accounts/abi/error.go
@@ -17,10 +17,15 @@
 package abi

 import (
+	"errors"
 	"fmt"
 	"reflect"
 )

+var (
+	errBadBool = errors.New("abi: improperly encoded boolean value")
+)
+
 // formatSliceString formats the reflection kind with the given slice size
 // and returns a formatted string representation.
 func formatSliceString(kind reflect.Kind, sliceSize int) string {
@@ -34,22 +39,23 @@ func formatSliceString(kind reflect.Kind, sliceSize int) string {
 // type in t.
 func sliceTypeCheck(t Type, val reflect.Value) error {
 	if val.Kind() != reflect.Slice && val.Kind() != reflect.Array {
-		return typeErr(formatSliceString(t.Kind, t.SliceSize), val.Type())
-	}
-	if t.IsArray && val.Len() != t.SliceSize {
-		return typeErr(formatSliceString(t.Elem.Kind, t.SliceSize), formatSliceString(val.Type().Elem().Kind(), val.Len()))
+		return typeErr(formatSliceString(t.Kind, t.Size), val.Type())
 	}

-	if t.Elem.IsSlice {
+	if t.T == ArrayTy && val.Len() != t.Size {
+		return typeErr(formatSliceString(t.Elem.Kind, t.Size), formatSliceString(val.Type().Elem().Kind(), val.Len()))
+	}
+
+	if t.Elem.T == SliceTy {
 		if val.Len() > 0 {
 			return sliceTypeCheck(*t.Elem, val.Index(0))
 		}
-	} else if t.Elem.IsArray {
+	} else if t.Elem.T == ArrayTy {
 		return sliceTypeCheck(*t.Elem, val.Index(0))
 	}

 	if elemKind := val.Type().Elem().Kind(); elemKind != t.Elem.Kind {
-		return typeErr(formatSliceString(t.Elem.Kind, t.SliceSize), val.Type())
+		return typeErr(formatSliceString(t.Elem.Kind, t.Size), val.Type())
 	}
 	return nil
 }
@@ -57,20 +63,19 @@ func sliceTypeCheck(t Type, val reflect.Value) error {
 // typeCheck checks that the given reflection value can be assigned to the reflection
 // type in t.
 func typeCheck(t Type, value reflect.Value) error {
-	if t.IsSlice || t.IsArray {
+	if t.T == SliceTy || t.T == ArrayTy {
 		return sliceTypeCheck(t, value)
 	}

 	// Check base type validity. Element types will be checked later on.
 	if t.Kind != value.Kind() {
 		return typeErr(t.Kind, value.Kind())
+	} else if t.T == FixedBytesTy && t.Size != value.Len() {
+		return typeErr(t.Type, value.Type())
+	} else {
+		return nil
 	}
-	return nil
-}

-// varErr returns a formatted error.
-func varErr(expected, got reflect.Kind) error {
-	return typeErr(expected, got)
 }

 // typeErr returns a formatted type casting error.
--- a/accounts/abi/event.go
+++ b/accounts/abi/event.go
@@ -25,10 +25,23 @@ import (
 )

 // Event is an event potentially triggered by the EVM's LOG mechanism. The Event
-// holds type information (inputs) about the yielded output
+// holds type information (inputs) about the yielded output. Anonymous events
+// don't get the signature canonical representation as the first LOG topic.
 type Event struct {
-	Name   string
-	Inputs []Argument
+	Name      string
+	Anonymous bool
+	Inputs    Arguments
+}
+
+func (event Event) String() string {
+	inputs := make([]string, len(event.Inputs))
+	for i, input := range event.Inputs {
+		inputs[i] = fmt.Sprintf("%v %v", input.Name, input.Type)
+		if input.Indexed {
+			inputs[i] = fmt.Sprintf("%v indexed %v", input.Name, input.Type)
+		}
+	}
+	return fmt.Sprintf("event %v(%v)", event.Name, strings.Join(inputs, ", "))
 }

 // Id returns the canonical representation of the event's signature used by the
--- a/accounts/abi/event_test.go
+++ b/accounts/abi/event_test.go
@@ -17,13 +17,53 @@
 package abi

 import (
+	"bytes"
+	"encoding/hex"
+	"encoding/json"
+	"math/big"
+	"reflect"
 	"strings"
 	"testing"

 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )

+var jsonEventTransfer = []byte(`{
+  "anonymous": false,
+  "inputs": [
+    {
+      "indexed": true, "name": "from", "type": "address"
+    }, {
+      "indexed": true, "name": "to", "type": "address"
+    }, {
+      "indexed": false, "name": "value", "type": "uint256"
+  }],
+  "name": "Transfer",
+  "type": "event"
+}`)
+
+var jsonEventPledge = []byte(`{
+  "anonymous": false,
+  "inputs": [{
+      "indexed": false, "name": "who", "type": "address"
+    }, {
+      "indexed": false, "name": "wad", "type": "uint128"
+    }, {
+      "indexed": false, "name": "currency", "type": "bytes3"
+  }],
+  "name": "Pledge",
+  "type": "event"
+}`)
+
+// 1000000
+var transferData1 = "00000000000000000000000000000000000000000000000000000000000f4240"
+
+// "0x00Ce0d46d924CC8437c806721496599FC3FFA268", 2218516807680, "usd"
+var pledgeData1 = "00000000000000000000000000ce0d46d924cc8437c806721496599fc3ffa2680000000000000000000000000000000000000000000000000000020489e800007573640000000000000000000000000000000000000000000000000000000000"
+
 func TestEventId(t *testing.T) {
 	var table = []struct {
 		definition   string
@@ -31,7 +71,7 @@ func TestEventId(t *testing.T) {
 	}{
 		{
 			definition: `[
-			{ "type" : "event", "name" : "balance", "inputs": [{ "name" : "in", "type": "uint" }] },
+			{ "type" : "event", "name" : "balance", "inputs": [{ "name" : "in", "type": "uint256" }] },
 			{ "type" : "event", "name" : "check", "inputs": [{ "name" : "t", "type": "address" }, { "name": "b", "type": "uint256" }] }
 			]`,
 			expectations: map[string]common.Hash{
@@ -54,3 +94,223 @@ func TestEventId(t *testing.T) {
 		}
 	}
 }
+
+// TestEventMultiValueWithArrayUnpack verifies that array fields will be counted after parsing array.
+func TestEventMultiValueWithArrayUnpack(t *testing.T) {
+	definition := `[{"name": "test", "type": "event", "inputs": [{"indexed": false, "name":"value1", "type":"uint8[2]"},{"indexed": false, "name":"value2", "type":"uint8"}]}]`
+	type testStruct struct {
+		Value1 [2]uint8
+		Value2 uint8
+	}
+	abi, err := JSON(strings.NewReader(definition))
+	require.NoError(t, err)
+	var b bytes.Buffer
+	var i uint8 = 1
+	for ; i <= 3; i++ {
+		b.Write(packNum(reflect.ValueOf(i)))
+	}
+	var rst testStruct
+	require.NoError(t, abi.Unpack(&rst, "test", b.Bytes()))
+	require.Equal(t, [2]uint8{1, 2}, rst.Value1)
+	require.Equal(t, uint8(3), rst.Value2)
+}
+
+func TestEventTupleUnpack(t *testing.T) {
+
+	type EventTransfer struct {
+		Value *big.Int
+	}
+
+	type EventPledge struct {
+		Who      common.Address
+		Wad      *big.Int
+		Currency [3]byte
+	}
+
+	type BadEventPledge struct {
+		Who      string
+		Wad      int
+		Currency [3]byte
+	}
+
+	bigint := new(big.Int)
+	bigintExpected := big.NewInt(1000000)
+	bigintExpected2 := big.NewInt(2218516807680)
+	addr := common.HexToAddress("0x00Ce0d46d924CC8437c806721496599FC3FFA268")
+	var testCases = []struct {
+		data     string
+		dest     interface{}
+		expected interface{}
+		jsonLog  []byte
+		error    string
+		name     string
+	}{{
+		transferData1,
+		&EventTransfer{},
+		&EventTransfer{Value: bigintExpected},
+		jsonEventTransfer,
+		"",
+		"Can unpack ERC20 Transfer event into structure",
+	}, {
+		transferData1,
+		&[]interface{}{&bigint},
+		&[]interface{}{&bigintExpected},
+		jsonEventTransfer,
+		"",
+		"Can unpack ERC20 Transfer event into slice",
+	}, {
+		pledgeData1,
+		&EventPledge{},
+		&EventPledge{
+			addr,
+			bigintExpected2,
+			[3]byte{'u', 's', 'd'}},
+		jsonEventPledge,
+		"",
+		"Can unpack Pledge event into structure",
+	}, {
+		pledgeData1,
+		&[]interface{}{&common.Address{}, &bigint, &[3]byte{}},
+		&[]interface{}{
+			&addr,
+			&bigintExpected2,
+			&[3]byte{'u', 's', 'd'}},
+		jsonEventPledge,
+		"",
+		"Can unpack Pledge event into slice",
+	}, {
+		pledgeData1,
+		&[3]interface{}{&common.Address{}, &bigint, &[3]byte{}},
+		&[3]interface{}{
+			&addr,
+			&bigintExpected2,
+			&[3]byte{'u', 's', 'd'}},
+		jsonEventPledge,
+		"",
+		"Can unpack Pledge event into an array",
+	}, {
+		pledgeData1,
+		&[]interface{}{new(int), 0, 0},
+		&[]interface{}{},
+		jsonEventPledge,
+		"abi: cannot unmarshal common.Address in to int",
+		"Can not unpack Pledge event into slice with wrong types",
+	}, {
+		pledgeData1,
+		&BadEventPledge{},
+		&BadEventPledge{},
+		jsonEventPledge,
+		"abi: cannot unmarshal common.Address in to string",
+		"Can not unpack Pledge event into struct with wrong filed types",
+	}, {
+		pledgeData1,
+		&[]interface{}{common.Address{}, new(big.Int)},
+		&[]interface{}{},
+		jsonEventPledge,
+		"abi: insufficient number of elements in the list/array for unpack, want 3, got 2",
+		"Can not unpack Pledge event into too short slice",
+	}, {
+		pledgeData1,
+		new(map[string]interface{}),
+		&[]interface{}{},
+		jsonEventPledge,
+		"abi: cannot unmarshal tuple into map[string]interface {}",
+		"Can not unpack Pledge event into map",
+	}}
+
+	for _, tc := range testCases {
+		assert := assert.New(t)
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			err := unpackTestEventData(tc.dest, tc.data, tc.jsonLog, assert)
+			if tc.error == "" {
+				assert.Nil(err, "Should be able to unpack event data.")
+				assert.Equal(tc.expected, tc.dest, tc.name)
+			} else {
+				assert.EqualError(err, tc.error)
+			}
+		})
+	}
+}
+
+func unpackTestEventData(dest interface{}, hexData string, jsonEvent []byte, assert *assert.Assertions) error {
+	data, err := hex.DecodeString(hexData)
+	assert.NoError(err, "Hex data should be a correct hex-string")
+	var e Event
+	assert.NoError(json.Unmarshal(jsonEvent, &e), "Should be able to unmarshal event ABI")
+	a := ABI{Events: map[string]Event{"e": e}}
+	return a.Unpack(dest, "e", data)
+}
+
+/*
+Taken from
+https://github.com/ethereum/go-ethereum/pull/15568
+*/
+
+type testResult struct {
+	Values [2]*big.Int
+	Value1 *big.Int
+	Value2 *big.Int
+}
+
+type testCase struct {
+	definition string
+	want       testResult
+}
+
+func (tc testCase) encoded(intType, arrayType Type) []byte {
+	var b bytes.Buffer
+	if tc.want.Value1 != nil {
+		val, _ := intType.pack(reflect.ValueOf(tc.want.Value1))
+		b.Write(val)
+	}
+
+	if !reflect.DeepEqual(tc.want.Values, [2]*big.Int{nil, nil}) {
+		val, _ := arrayType.pack(reflect.ValueOf(tc.want.Values))
+		b.Write(val)
+	}
+	if tc.want.Value2 != nil {
+		val, _ := intType.pack(reflect.ValueOf(tc.want.Value2))
+		b.Write(val)
+	}
+	return b.Bytes()
+}
+
+// TestEventUnpackIndexed verifies that indexed field will be skipped by event decoder.
+func TestEventUnpackIndexed(t *testing.T) {
+	definition := `[{"name": "test", "type": "event", "inputs": [{"indexed": true, "name":"value1", "type":"uint8"},{"indexed": false, "name":"value2", "type":"uint8"}]}]`
+	type testStruct struct {
+		Value1 uint8
+		Value2 uint8
+	}
+	abi, err := JSON(strings.NewReader(definition))
+	require.NoError(t, err)
+	var b bytes.Buffer
+	b.Write(packNum(reflect.ValueOf(uint8(8))))
+	var rst testStruct
+	require.NoError(t, abi.Unpack(&rst, "test", b.Bytes()))
+	require.Equal(t, uint8(0), rst.Value1)
+	require.Equal(t, uint8(8), rst.Value2)
+}
+
+// TestEventIndexedWithArrayUnpack verifies that decoder will not overlow when static array is indexed input.
+func TestEventIndexedWithArrayUnpack(t *testing.T) {
+	definition := `[{"name": "test", "type": "event", "inputs": [{"indexed": true, "name":"value1", "type":"uint8[2]"},{"indexed": false, "name":"value2", "type":"string"}]}]`
+	type testStruct struct {
+		Value1 [2]uint8
+		Value2 string
+	}
+	abi, err := JSON(strings.NewReader(definition))
+	require.NoError(t, err)
+	var b bytes.Buffer
+	stringOut := "abc"
+	// number of fields that will be encoded * 32
+	b.Write(packNum(reflect.ValueOf(32)))
+	b.Write(packNum(reflect.ValueOf(len(stringOut))))
+	b.Write(common.RightPadBytes([]byte(stringOut), 32))
+
+	var rst testStruct
+	require.NoError(t, abi.Unpack(&rst, "test", b.Bytes()))
+	require.Equal(t, [2]uint8{0, 0}, rst.Value1)
+	require.Equal(t, stringOut, rst.Value2)
+}
--- a/accounts/abi/method.go
+++ b/accounts/abi/method.go
@@ -18,13 +18,12 @@ package abi

 import (
 	"fmt"
-	"reflect"
 	"strings"

 	"github.com/ethereum/go-ethereum/crypto"
 )

-// Callable method given a `Name` and whether the method is a constant.
+// Method represents a callable given a `Name` and whether the method is a constant.
 // If the method is `Const` no transaction needs to be created for this
 // particular Method call. It can easily be simulated using a local VM.
 // For example a `Balance()` method only needs to retrieve something
@@ -35,46 +34,8 @@ import (
 type Method struct {
 	Name    string
 	Const   bool
-	Inputs  []Argument
-	Outputs []Argument
-}
-
-func (m Method) pack(method Method, args ...interface{}) ([]byte, error) {
-	// Make sure arguments match up and pack them
-	if len(args) != len(method.Inputs) {
-		return nil, fmt.Errorf("argument count mismatch: %d for %d", len(args), len(method.Inputs))
-	}
-	// variable input is the output appended at the end of packed
-	// output. This is used for strings and bytes types input.
-	var variableInput []byte
-
-	var ret []byte
-	for i, a := range args {
-		input := method.Inputs[i]
-		// pack the input
-		packed, err := input.Type.pack(reflect.ValueOf(a))
-		if err != nil {
-			return nil, fmt.Errorf("`%s` %v", method.Name, err)
-		}
-
-		// check for a slice type (string, bytes, slice)
-		if input.Type.requiresLengthPrefix() {
-			// calculate the offset
-			offset := len(method.Inputs)*32 + len(variableInput)
-			// set the offset
-			ret = append(ret, packNum(reflect.ValueOf(offset))...)
-			// Append the packed output to the variable input. The variable input
-			// will be appended at the end of the input.
-			variableInput = append(variableInput, packed...)
-		} else {
-			// append the packed value to the input
-			ret = append(ret, packed...)
-		}
-	}
-	// append the variable input at the end of the packed input
-	ret = append(ret, variableInput...)
-
-	return ret, nil
+	Inputs  Arguments
+	Outputs Arguments
 }

 // Sig returns the methods string signature according to the ABI spec.
@@ -84,35 +45,35 @@ func (m Method) pack(method Method, args ...interface{}) ([]byte, error) {
 //     function foo(uint32 a, int b)    =    "foo(uint32,int256)"
 //
 // Please note that "int" is substitute for its canonical representation "int256"
-func (m Method) Sig() string {
-	types := make([]string, len(m.Inputs))
+func (method Method) Sig() string {
+	types := make([]string, len(method.Inputs))
 	i := 0
-	for _, input := range m.Inputs {
+	for _, input := range method.Inputs {
 		types[i] = input.Type.String()
 		i++
 	}
-	return fmt.Sprintf("%v(%v)", m.Name, strings.Join(types, ","))
+	return fmt.Sprintf("%v(%v)", method.Name, strings.Join(types, ","))
 }

-func (m Method) String() string {
-	inputs := make([]string, len(m.Inputs))
-	for i, input := range m.Inputs {
+func (method Method) String() string {
+	inputs := make([]string, len(method.Inputs))
+	for i, input := range method.Inputs {
 		inputs[i] = fmt.Sprintf("%v %v", input.Name, input.Type)
 	}
-	outputs := make([]string, len(m.Outputs))
-	for i, output := range m.Outputs {
+	outputs := make([]string, len(method.Outputs))
+	for i, output := range method.Outputs {
 		if len(output.Name) > 0 {
 			outputs[i] = fmt.Sprintf("%v ", output.Name)
 		}
 		outputs[i] += output.Type.String()
 	}
 	constant := ""
-	if m.Const {
+	if method.Const {
 		constant = "constant "
 	}
-	return fmt.Sprintf("function %v(%v) %sreturns(%v)", m.Name, strings.Join(inputs, ", "), constant, strings.Join(outputs, ", "))
+	return fmt.Sprintf("function %v(%v) %sreturns(%v)", method.Name, strings.Join(inputs, ", "), constant, strings.Join(outputs, ", "))
 }

-func (m Method) Id() []byte {
-	return crypto.Keccak256([]byte(m.Sig()))[:4]
+func (method Method) Id() []byte {
+	return crypto.Keccak256([]byte(method.Sig()))[:4]
 }
--- a/accounts/abi/numbers.go
+++ b/accounts/abi/numbers.go
@@ -21,57 +21,32 @@ import (
 	"reflect"

 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/math"
 )

 var (
-	big_t     = reflect.TypeOf(big.Int{})
-	ubig_t    = reflect.TypeOf(big.Int{})
-	byte_t    = reflect.TypeOf(byte(0))
-	byte_ts   = reflect.TypeOf([]byte(nil))
-	uint_t    = reflect.TypeOf(uint(0))
-	uint8_t   = reflect.TypeOf(uint8(0))
-	uint16_t  = reflect.TypeOf(uint16(0))
-	uint32_t  = reflect.TypeOf(uint32(0))
-	uint64_t  = reflect.TypeOf(uint64(0))
-	int_t     = reflect.TypeOf(int(0))
-	int8_t    = reflect.TypeOf(int8(0))
-	int16_t   = reflect.TypeOf(int16(0))
-	int32_t   = reflect.TypeOf(int32(0))
-	int64_t   = reflect.TypeOf(int64(0))
-	hash_t    = reflect.TypeOf(common.Hash{})
-	address_t = reflect.TypeOf(common.Address{})
-
-	uint_ts   = reflect.TypeOf([]uint(nil))
-	uint8_ts  = reflect.TypeOf([]uint8(nil))
-	uint16_ts = reflect.TypeOf([]uint16(nil))
-	uint32_ts = reflect.TypeOf([]uint32(nil))
-	uint64_ts = reflect.TypeOf([]uint64(nil))
-	ubig_ts   = reflect.TypeOf([]*big.Int(nil))
-
-	int_ts   = reflect.TypeOf([]int(nil))
-	int8_ts  = reflect.TypeOf([]int8(nil))
-	int16_ts = reflect.TypeOf([]int16(nil))
-	int32_ts = reflect.TypeOf([]int32(nil))
-	int64_ts = reflect.TypeOf([]int64(nil))
-	big_ts   = reflect.TypeOf([]*big.Int(nil))
+	big_t      = reflect.TypeOf(&big.Int{})
+	derefbig_t = reflect.TypeOf(big.Int{})
+	uint8_t    = reflect.TypeOf(uint8(0))
+	uint16_t   = reflect.TypeOf(uint16(0))
+	uint32_t   = reflect.TypeOf(uint32(0))
+	uint64_t   = reflect.TypeOf(uint64(0))
+	int_t      = reflect.TypeOf(int(0))
+	int8_t     = reflect.TypeOf(int8(0))
+	int16_t    = reflect.TypeOf(int16(0))
+	int32_t    = reflect.TypeOf(int32(0))
+	int64_t    = reflect.TypeOf(int64(0))
+	address_t  = reflect.TypeOf(common.Address{})
+	int_ts     = reflect.TypeOf([]int(nil))
+	int8_ts    = reflect.TypeOf([]int8(nil))
+	int16_ts   = reflect.TypeOf([]int16(nil))
+	int32_ts   = reflect.TypeOf([]int32(nil))
+	int64_ts   = reflect.TypeOf([]int64(nil))
 )

 // U256 converts a big Int into a 256bit EVM number.
 func U256(n *big.Int) []byte {
-	return common.LeftPadBytes(common.U256(n).Bytes(), 32)
-}
-
-// packNum packs the given number (using the reflect value) and will cast it to appropriate number representation
-func packNum(value reflect.Value) []byte {
-	switch kind := value.Kind(); kind {
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
-		return U256(new(big.Int).SetUint64(value.Uint()))
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		return U256(big.NewInt(value.Int()))
-	case reflect.Ptr:
-		return U256(value.Interface().(*big.Int))
-	}
-	return nil
+	return math.PaddedBigBytes(math.U256(n), 32)
 }

 // checks whether the given reflect value is signed. This also works for slices with a number type
--- a/accounts/abi/numbers_test.go
+++ b/accounts/abi/numbers_test.go
@@ -18,7 +18,6 @@ package abi

 import (
 	"bytes"
-	"math"
 	"math/big"
 	"reflect"
 	"testing"
@@ -34,43 +33,6 @@ func TestNumberTypes(t *testing.T) {
 	}
 }

-func TestPackNumber(t *testing.T) {
-	tests := []struct {
-		value  reflect.Value
-		packed []byte
-	}{
-		// Protocol limits
-		{reflect.ValueOf(0), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
-		{reflect.ValueOf(1), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}},
-		{reflect.ValueOf(-1), []byte{255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}},
-
-		// Type corner cases
-		{reflect.ValueOf(uint8(math.MaxUint8)), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255}},
-		{reflect.ValueOf(uint16(math.MaxUint16)), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255}},
-		{reflect.ValueOf(uint32(math.MaxUint32)), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255, 255, 255}},
-		{reflect.ValueOf(uint64(math.MaxUint64)), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255, 255, 255, 255, 255, 255, 255}},
-
-		{reflect.ValueOf(int8(math.MaxInt8)), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 127}},
-		{reflect.ValueOf(int16(math.MaxInt16)), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 127, 255}},
-		{reflect.ValueOf(int32(math.MaxInt32)), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 127, 255, 255, 255}},
-		{reflect.ValueOf(int64(math.MaxInt64)), []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 127, 255, 255, 255, 255, 255, 255, 255}},
-
-		{reflect.ValueOf(int8(math.MinInt8)), []byte{255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 128}},
-		{reflect.ValueOf(int16(math.MinInt16)), []byte{255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 128, 0}},
-		{reflect.ValueOf(int32(math.MinInt32)), []byte{255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 128, 0, 0, 0}},
-		{reflect.ValueOf(int64(math.MinInt64)), []byte{255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 128, 0, 0, 0, 0, 0, 0, 0}},
-	}
-	for i, tt := range tests {
-		packed := packNum(tt.value)
-		if !bytes.Equal(packed, tt.packed) {
-			t.Errorf("test %d: pack mismatch: have %x, want %x", i, packed, tt.packed)
-		}
-	}
-	if packed := packNum(reflect.ValueOf("string")); packed != nil {
-		t.Errorf("expected 'string' to pack to nil. got %x instead", packed)
-	}
-}
-
 func TestSigned(t *testing.T) {
 	if isSigned(reflect.ValueOf(uint(10))) {
 		t.Error("signed")
--- a/accounts/abi/pack.go
+++ b/accounts/abi/pack.go
@@ -0,0 +1,81 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package abi
+
+import (
+	"math/big"
+	"reflect"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/math"
+)
+
+// packBytesSlice packs the given bytes as [L, V] as the canonical representation
+// bytes slice
+func packBytesSlice(bytes []byte, l int) []byte {
+	len := packNum(reflect.ValueOf(l))
+	return append(len, common.RightPadBytes(bytes, (l+31)/32*32)...)
+}
+
+// packElement packs the given reflect value according to the abi specification in
+// t.
+func packElement(t Type, reflectValue reflect.Value) []byte {
+	switch t.T {
+	case IntTy, UintTy:
+		return packNum(reflectValue)
+	case StringTy:
+		return packBytesSlice([]byte(reflectValue.String()), reflectValue.Len())
+	case AddressTy:
+		if reflectValue.Kind() == reflect.Array {
+			reflectValue = mustArrayToByteSlice(reflectValue)
+		}
+
+		return common.LeftPadBytes(reflectValue.Bytes(), 32)
+	case BoolTy:
+		if reflectValue.Bool() {
+			return math.PaddedBigBytes(common.Big1, 32)
+		}
+		return math.PaddedBigBytes(common.Big0, 32)
+	case BytesTy:
+		if reflectValue.Kind() == reflect.Array {
+			reflectValue = mustArrayToByteSlice(reflectValue)
+		}
+		return packBytesSlice(reflectValue.Bytes(), reflectValue.Len())
+	case FixedBytesTy, FunctionTy:
+		if reflectValue.Kind() == reflect.Array {
+			reflectValue = mustArrayToByteSlice(reflectValue)
+		}
+		return common.RightPadBytes(reflectValue.Bytes(), 32)
+	default:
+		panic("abi: fatal error")
+	}
+}
+
+// packNum packs the given number (using the reflect value) and will cast it to appropriate number representation
+func packNum(value reflect.Value) []byte {
+	switch kind := value.Kind(); kind {
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return U256(new(big.Int).SetUint64(value.Uint()))
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return U256(big.NewInt(value.Int()))
+	case reflect.Ptr:
+		return U256(value.Interface().(*big.Int))
+	default:
+		panic("abi: fatal error")
+	}
+
+}
--- a/accounts/abi/pack_test.go
+++ b/accounts/abi/pack_test.go
@@ -0,0 +1,443 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package abi
+
+import (
+	"bytes"
+	"math"
+	"math/big"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+func TestPack(t *testing.T) {
+	for i, test := range []struct {
+		typ string
+
+		input  interface{}
+		output []byte
+	}{
+		{
+			"uint8",
+			uint8(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint8[]",
+			[]uint8{1, 2},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint16",
+			uint16(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint16[]",
+			[]uint16{1, 2},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint32",
+			uint32(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint32[]",
+			[]uint32{1, 2},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint64",
+			uint64(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint64[]",
+			[]uint64{1, 2},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint256",
+			big.NewInt(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"uint256[]",
+			[]*big.Int{big.NewInt(1), big.NewInt(2)},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int8",
+			int8(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int8[]",
+			[]int8{1, 2},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int16",
+			int16(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int16[]",
+			[]int16{1, 2},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int32",
+			int32(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int32[]",
+			[]int32{1, 2},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int64",
+			int64(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int64[]",
+			[]int64{1, 2},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int256",
+			big.NewInt(2),
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"int256[]",
+			[]*big.Int{big.NewInt(1), big.NewInt(2)},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
+		},
+		{
+			"bytes1",
+			[1]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes2",
+			[2]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes3",
+			[3]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes4",
+			[4]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes5",
+			[5]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes6",
+			[6]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes7",
+			[7]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes8",
+			[8]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes9",
+			[9]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes10",
+			[10]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes11",
+			[11]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes12",
+			[12]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes13",
+			[13]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes14",
+			[14]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes15",
+			[15]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes16",
+			[16]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes17",
+			[17]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes18",
+			[18]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes19",
+			[19]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes20",
+			[20]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes21",
+			[21]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes22",
+			[22]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes23",
+			[23]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes24",
+			[24]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes24",
+			[24]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes25",
+			[25]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes26",
+			[26]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes27",
+			[27]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes28",
+			[28]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes29",
+			[29]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes30",
+			[30]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes31",
+			[31]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"bytes32",
+			[32]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"uint32[2][3][4]",
+			[4][3][2]uint32{{{1, 2}, {3, 4}, {5, 6}}, {{7, 8}, {9, 10}, {11, 12}}, {{13, 14}, {15, 16}, {17, 18}}, {{19, 20}, {21, 22}, {23, 24}}},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000700000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000f000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000110000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000000000000001300000000000000000000000000000000000000000000000000000000000000140000000000000000000000000000000000000000000000000000000000000015000000000000000000000000000000000000000000000000000000000000001600000000000000000000000000000000000000000000000000000000000000170000000000000000000000000000000000000000000000000000000000000018"),
+		},
+		{
+			"address[]",
+			[]common.Address{{1}, {2}},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000200000000000000000000000001000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000"),
+		},
+		{
+			"bytes32[]",
+			[]common.Hash{{1}, {2}},
+			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000201000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"function",
+			[24]byte{1},
+			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+		},
+		{
+			"string",
+			"foobar",
+			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000006666f6f6261720000000000000000000000000000000000000000000000000000"),
+		},
+	} {
+		typ, err := NewType(test.typ)
+		if err != nil {
+			t.Fatalf("%v failed. Unexpected parse error: %v", i, err)
+		}
+
+		output, err := typ.pack(reflect.ValueOf(test.input))
+		if err != nil {
+			t.Fatalf("%v failed. Unexpected pack error: %v", i, err)
+		}
+
+		if !bytes.Equal(output, test.output) {
+			t.Errorf("%d failed. Expected bytes: '%x' Got: '%x'", i, test.output, output)
+		}
+	}
+}
+
+func TestMethodPack(t *testing.T) {
+	abi, err := JSON(strings.NewReader(jsondata2))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	sig := abi.Methods["slice"].Id()
+	sig = append(sig, common.LeftPadBytes([]byte{1}, 32)...)
+	sig = append(sig, common.LeftPadBytes([]byte{2}, 32)...)
+
+	packed, err := abi.Pack("slice", []uint32{1, 2})
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !bytes.Equal(packed, sig) {
+		t.Errorf("expected %x got %x", sig, packed)
+	}
+
+	var addrA, addrB = common.Address{1}, common.Address{2}
+	sig = abi.Methods["sliceAddress"].Id()
+	sig = append(sig, common.LeftPadBytes([]byte{32}, 32)...)
+	sig = append(sig, common.LeftPadBytes([]byte{2}, 32)...)
+	sig = append(sig, common.LeftPadBytes(addrA[:], 32)...)
+	sig = append(sig, common.LeftPadBytes(addrB[:], 32)...)
+
+	packed, err = abi.Pack("sliceAddress", []common.Address{addrA, addrB})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(packed, sig) {
+		t.Errorf("expected %x got %x", sig, packed)
+	}
+
+	var addrC, addrD = common.Address{3}, common.Address{4}
+	sig = abi.Methods["sliceMultiAddress"].Id()
+	sig = append(sig, common.LeftPadBytes([]byte{64}, 32)...)
+	sig = append(sig, common.LeftPadBytes([]byte{160}, 32)...)
+	sig = append(sig, common.LeftPadBytes([]byte{2}, 32)...)
+	sig = append(sig, common.LeftPadBytes(addrA[:], 32)...)
+	sig = append(sig, common.LeftPadBytes(addrB[:], 32)...)
+	sig = append(sig, common.LeftPadBytes([]byte{2}, 32)...)
+	sig = append(sig, common.LeftPadBytes(addrC[:], 32)...)
+	sig = append(sig, common.LeftPadBytes(addrD[:], 32)...)
+
+	packed, err = abi.Pack("sliceMultiAddress", []common.Address{addrA, addrB}, []common.Address{addrC, addrD})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(packed, sig) {
+		t.Errorf("expected %x got %x", sig, packed)
+	}
+
+	sig = abi.Methods["slice256"].Id()
+	sig = append(sig, common.LeftPadBytes([]byte{1}, 32)...)
+	sig = append(sig, common.LeftPadBytes([]byte{2}, 32)...)
+
+	packed, err = abi.Pack("slice256", []*big.Int{big.NewInt(1), big.NewInt(2)})
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !bytes.Equal(packed, sig) {
+		t.Errorf("expected %x got %x", sig, packed)
+	}
+}
+
+func TestPackNumber(t *testing.T) {
+	tests := []struct {
+		value  reflect.Value
+		packed []byte
+	}{
+		// Protocol limits
+		{reflect.ValueOf(0), common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000000")},
+		{reflect.ValueOf(1), common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001")},
+		{reflect.ValueOf(-1), common.Hex2Bytes("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff")},
+
+		// Type corner cases
+		{reflect.ValueOf(uint8(math.MaxUint8)), common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000ff")},
+		{reflect.ValueOf(uint16(math.MaxUint16)), common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000ffff")},
+		{reflect.ValueOf(uint32(math.MaxUint32)), common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000ffffffff")},
+		{reflect.ValueOf(uint64(math.MaxUint64)), common.Hex2Bytes("000000000000000000000000000000000000000000000000ffffffffffffffff")},
+
+		{reflect.ValueOf(int8(math.MaxInt8)), common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000007f")},
+		{reflect.ValueOf(int16(math.MaxInt16)), common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000007fff")},
+		{reflect.ValueOf(int32(math.MaxInt32)), common.Hex2Bytes("000000000000000000000000000000000000000000000000000000007fffffff")},
+		{reflect.ValueOf(int64(math.MaxInt64)), common.Hex2Bytes("0000000000000000000000000000000000000000000000007fffffffffffffff")},
+
+		{reflect.ValueOf(int8(math.MinInt8)), common.Hex2Bytes("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff80")},
+		{reflect.ValueOf(int16(math.MinInt16)), common.Hex2Bytes("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff8000")},
+		{reflect.ValueOf(int32(math.MinInt32)), common.Hex2Bytes("ffffffffffffffffffffffffffffffffffffffffffffffffffffffff80000000")},
+		{reflect.ValueOf(int64(math.MinInt64)), common.Hex2Bytes("ffffffffffffffffffffffffffffffffffffffffffffffff8000000000000000")},
+	}
+	for i, tt := range tests {
+		packed := packNum(tt.value)
+		if !bytes.Equal(packed, tt.packed) {
+			t.Errorf("test %d: pack mismatch: have %x, want %x", i, packed, tt.packed)
+		}
+	}
+}
--- a/accounts/abi/packing.go
+++ b/accounts/abi/packing.go
@@ -1,65 +0,0 @@
-// Copyright 2016 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package abi
-
-import (
-	"reflect"
-
-	"github.com/ethereum/go-ethereum/common"
-)
-
-// packBytesSlice packs the given bytes as [L, V] as the canonical representation
-// bytes slice
-func packBytesSlice(bytes []byte, l int) []byte {
-	len := packNum(reflect.ValueOf(l))
-	return append(len, common.RightPadBytes(bytes, (l+31)/32*32)...)
-}
-
-// packElement packs the given reflect value according to the abi specification in
-// t.
-func packElement(t Type, reflectValue reflect.Value) []byte {
-	switch t.T {
-	case IntTy, UintTy:
-		return packNum(reflectValue)
-	case StringTy:
-		return packBytesSlice([]byte(reflectValue.String()), reflectValue.Len())
-	case AddressTy:
-		if reflectValue.Kind() == reflect.Array {
-			reflectValue = mustArrayToByteSlice(reflectValue)
-		}
-
-		return common.LeftPadBytes(reflectValue.Bytes(), 32)
-	case BoolTy:
-		if reflectValue.Bool() {
-			return common.LeftPadBytes(common.Big1.Bytes(), 32)
-		} else {
-			return common.LeftPadBytes(common.Big0.Bytes(), 32)
-		}
-	case BytesTy:
-		if reflectValue.Kind() == reflect.Array {
-			reflectValue = mustArrayToByteSlice(reflectValue)
-		}
-		return packBytesSlice(reflectValue.Bytes(), reflectValue.Len())
-	case FixedBytesTy:
-		if reflectValue.Kind() == reflect.Array {
-			reflectValue = mustArrayToByteSlice(reflectValue)
-		}
-
-		return common.RightPadBytes(reflectValue.Bytes(), 32)
-	}
-	panic("abi: fatal error")
-}
--- a/accounts/abi/reflect.go
+++ b/accounts/abi/reflect.go
@@ -24,7 +24,7 @@ import (
 // indirect recursively dereferences the value until it either gets the value
 // or finds a big.Int
 func indirect(v reflect.Value) reflect.Value {
-	if v.Kind() == reflect.Ptr && v.Elem().Type() != big_t {
+	if v.Kind() == reflect.Ptr && v.Elem().Type() != derefbig_t {
 		return indirect(v.Elem())
 	}
 	return v
@@ -32,30 +32,30 @@ func indirect(v reflect.Value) reflect.Value {

 // reflectIntKind returns the reflect using the given size and
 // unsignedness.
-func reflectIntKind(unsigned bool, size int) reflect.Kind {
+func reflectIntKindAndType(unsigned bool, size int) (reflect.Kind, reflect.Type) {
 	switch size {
 	case 8:
 		if unsigned {
-			return reflect.Uint8
+			return reflect.Uint8, uint8_t
 		}
-		return reflect.Int8
+		return reflect.Int8, int8_t
 	case 16:
 		if unsigned {
-			return reflect.Uint16
+			return reflect.Uint16, uint16_t
 		}
-		return reflect.Int16
+		return reflect.Int16, int16_t
 	case 32:
 		if unsigned {
-			return reflect.Uint32
+			return reflect.Uint32, uint32_t
 		}
-		return reflect.Int32
+		return reflect.Int32, int32_t
 	case 64:
 		if unsigned {
-			return reflect.Uint64
+			return reflect.Uint64, uint64_t
 		}
-		return reflect.Int64
+		return reflect.Int64, int64_t
 	}
-	return reflect.Ptr
+	return reflect.Ptr, big_t
 }

 // mustArrayToBytesSlice creates a new byte slice with the exact same size as value
@@ -73,15 +73,9 @@ func mustArrayToByteSlice(value reflect.Value) reflect.Value {
 func set(dst, src reflect.Value, output Argument) error {
 	dstType := dst.Type()
 	srcType := src.Type()
-
 	switch {
-	case dstType.AssignableTo(src.Type()):
+	case dstType.AssignableTo(srcType):
 		dst.Set(src)
-	case dstType.Kind() == reflect.Array && srcType.Kind() == reflect.Slice:
-		if dst.Len() < output.Type.SliceSize {
-			return fmt.Errorf("abi: cannot unmarshal src (len=%d) in to dst (len=%d)", output.Type.SliceSize, dst.Len())
-		}
-		reflect.Copy(dst, src)
 	case dstType.Kind() == reflect.Interface:
 		dst.Set(src)
 	case dstType.Kind() == reflect.Ptr:
@@ -91,3 +85,28 @@ func set(dst, src reflect.Value, output Argument) error {
 	}
 	return nil
 }
+
+// requireAssignable assures that `dest` is a pointer and it's not an interface.
+func requireAssignable(dst, src reflect.Value) error {
+	if dst.Kind() != reflect.Ptr && dst.Kind() != reflect.Interface {
+		return fmt.Errorf("abi: cannot unmarshal %v into %v", src.Type(), dst.Type())
+	}
+	return nil
+}
+
+// requireUnpackKind verifies preconditions for unpacking `args` into `kind`
+func requireUnpackKind(v reflect.Value, t reflect.Type, k reflect.Kind,
+	args Arguments) error {
+
+	switch k {
+	case reflect.Struct:
+	case reflect.Slice, reflect.Array:
+		if minLen := args.LengthNonIndexed(); v.Len() < minLen {
+			return fmt.Errorf("abi: insufficient number of elements in the list/array for unpack, want %d, got %d",
+				minLen, v.Len())
+		}
+	default:
+		return fmt.Errorf("abi: cannot unmarshal tuple into %v", t)
+	}
+	return nil
+}
--- a/accounts/abi/type.go
+++ b/accounts/abi/type.go
@@ -21,26 +21,27 @@ import (
 	"reflect"
 	"regexp"
 	"strconv"
+	"strings"
 )

+// Type enumerator
 const (
 	IntTy byte = iota
 	UintTy
 	BoolTy
 	StringTy
 	SliceTy
+	ArrayTy
 	AddressTy
 	FixedBytesTy
 	BytesTy
 	HashTy
-	RealTy
+	FixedPointTy
+	FunctionTy
 )

 // Type is the reflection of the supported argument type
 type Type struct {
-	IsSlice, IsArray bool
-	SliceSize        int
-
 	Elem *Type

 	Kind reflect.Kind
@@ -52,81 +53,86 @@ type Type struct {
 }

 var (
-	// fullTypeRegex parses the abi types
-	//
-	// Types can be in the format of:
-	//
-	// 	Input  = Type [ "[" [ Number ] "]" ] Name .
-	// 	Type   = [ "u" ] "int" [ Number ] .
-	//
-	// Examples:
-	//
-	//      string     int       uint       real
-	//      string32   int8      uint8      uint[]
-	//      address    int256    uint256    real[2]
-	fullTypeRegex = regexp.MustCompile("([a-zA-Z0-9]+)(\\[([0-9]*)?\\])?")
 	// typeRegex parses the abi sub types
-	typeRegex = regexp.MustCompile("([a-zA-Z]+)([0-9]*)?")
+	typeRegex = regexp.MustCompile("([a-zA-Z]+)(([0-9]+)(x([0-9]+))?)?")
 )

 // NewType creates a new reflection type of abi type given in t.
 func NewType(t string) (typ Type, err error) {
-	res := fullTypeRegex.FindAllStringSubmatch(t, -1)[0]
-	// check if type is slice and parse type.
-	switch {
-	case res[3] != "":
-		// err is ignored. Already checked for number through the regexp
-		typ.SliceSize, _ = strconv.Atoi(res[3])
-		typ.IsArray = true
-	case res[2] != "":
-		typ.IsSlice, typ.SliceSize = true, -1
-	case res[0] == "":
-		return Type{}, fmt.Errorf("abi: type parse error: %s", t)
+	// check that array brackets are equal if they exist
+	if strings.Count(t, "[") != strings.Count(t, "]") {
+		return Type{}, fmt.Errorf("invalid arg type in abi")
 	}
-	if typ.IsArray || typ.IsSlice {
-		sliceType, err := NewType(res[1])
+
+	typ.stringKind = t
+
+	// if there are brackets, get ready to go into slice/array mode and
+	// recursively create the type
+	if strings.Count(t, "[") != 0 {
+		i := strings.LastIndex(t, "[")
+		// recursively embed the type
+		embeddedType, err := NewType(t[:i])
 		if err != nil {
 			return Type{}, err
 		}
-		typ.Elem = &sliceType
-		typ.stringKind = sliceType.stringKind + t[len(res[1]):]
-		return typ, nil
-	}
+		// grab the last cell and create a type from there
+		sliced := t[i:]
+		// grab the slice size with regexp
+		re := regexp.MustCompile("[0-9]+")
+		intz := re.FindAllString(sliced, -1)

+		if len(intz) == 0 {
+			// is a slice
+			typ.T = SliceTy
+			typ.Kind = reflect.Slice
+			typ.Elem = &embeddedType
+			typ.Type = reflect.SliceOf(embeddedType.Type)
+		} else if len(intz) == 1 {
+			// is a array
+			typ.T = ArrayTy
+			typ.Kind = reflect.Array
+			typ.Elem = &embeddedType
+			typ.Size, err = strconv.Atoi(intz[0])
+			if err != nil {
+				return Type{}, fmt.Errorf("abi: error parsing variable size: %v", err)
+			}
+			typ.Type = reflect.ArrayOf(typ.Size, embeddedType.Type)
+		} else {
+			return Type{}, fmt.Errorf("invalid formatting of array type")
+		}
+		return typ, err
+	}
 	// parse the type and size of the abi-type.
-	parsedType := typeRegex.FindAllStringSubmatch(res[1], -1)[0]
+	parsedType := typeRegex.FindAllStringSubmatch(t, -1)[0]
 	// varSize is the size of the variable
 	var varSize int
-	if len(parsedType[2]) > 0 {
+	if len(parsedType[3]) > 0 {
 		var err error
 		varSize, err = strconv.Atoi(parsedType[2])
 		if err != nil {
 			return Type{}, fmt.Errorf("abi: error parsing variable size: %v", err)
 		}
+	} else {
+		if parsedType[0] == "uint" || parsedType[0] == "int" {
+			// this should fail because it means that there's something wrong with
+			// the abi type (the compiler should always format it to the size...always)
+			return Type{}, fmt.Errorf("unsupported arg type: %s", t)
+		}
 	}
 	// varType is the parsed abi type
-	varType := parsedType[1]
-	// substitute canonical integer
-	if varSize == 0 && (varType == "int" || varType == "uint") {
-		varSize = 256
-		t += "256"
-	}
-	typ.stringKind = t
-
-	switch varType {
+	switch varType := parsedType[1]; varType {
 	case "int":
-		typ.Kind = reflectIntKind(false, varSize)
-		typ.Type = big_t
+		typ.Kind, typ.Type = reflectIntKindAndType(false, varSize)
 		typ.Size = varSize
 		typ.T = IntTy
 	case "uint":
-		typ.Kind = reflectIntKind(true, varSize)
-		typ.Type = ubig_t
+		typ.Kind, typ.Type = reflectIntKindAndType(true, varSize)
 		typ.Size = varSize
 		typ.T = UintTy
 	case "bool":
 		typ.Kind = reflect.Bool
 		typ.T = BoolTy
+		typ.Type = reflect.TypeOf(bool(false))
 	case "address":
 		typ.Kind = reflect.Array
 		typ.Type = address_t
@@ -134,20 +140,24 @@ func NewType(t string) (typ Type, err error) {
 		typ.T = AddressTy
 	case "string":
 		typ.Kind = reflect.String
-		typ.Size = -1
+		typ.Type = reflect.TypeOf("")
 		typ.T = StringTy
 	case "bytes":
-		sliceType, _ := NewType("uint8")
-		typ.Elem = &sliceType
 		if varSize == 0 {
-			typ.IsSlice = true
 			typ.T = BytesTy
-			typ.SliceSize = -1
+			typ.Kind = reflect.Slice
+			typ.Type = reflect.SliceOf(reflect.TypeOf(byte(0)))
 		} else {
-			typ.IsArray = true
 			typ.T = FixedBytesTy
-			typ.SliceSize = varSize
+			typ.Kind = reflect.Array
+			typ.Size = varSize
+			typ.Type = reflect.ArrayOf(varSize, reflect.TypeOf(byte(0)))
 		}
+	case "function":
+		typ.Kind = reflect.Array
+		typ.T = FunctionTy
+		typ.Size = 24
+		typ.Type = reflect.ArrayOf(24, reflect.TypeOf(byte(0)))
 	default:
 		return Type{}, fmt.Errorf("unsupported arg type: %s", t)
 	}
@@ -168,7 +178,7 @@ func (t Type) pack(v reflect.Value) ([]byte, error) {
 		return nil, err
 	}

-	if (t.IsSlice || t.IsArray) && t.T != BytesTy && t.T != FixedBytesTy {
+	if t.T == SliceTy || t.T == ArrayTy {
 		var packed []byte

 		for i := 0; i < v.Len(); i++ {
@@ -178,18 +188,17 @@ func (t Type) pack(v reflect.Value) ([]byte, error) {
 			}
 			packed = append(packed, val...)
 		}
-		if t.IsSlice {
+		if t.T == SliceTy {
 			return packBytesSlice(packed, v.Len()), nil
-		} else if t.IsArray {
+		} else if t.T == ArrayTy {
 			return packed, nil
 		}
 	}
-
 	return packElement(t, v), nil
 }

 // requireLengthPrefix returns whether the type requires any sort of length
 // prefixing.
 func (t Type) requiresLengthPrefix() bool {
-	return t.T != FixedBytesTy && (t.T == StringTy || t.T == BytesTy || t.IsSlice)
+	return t.T == StringTy || t.T == BytesTy || t.T == SliceTy
 }
--- a/accounts/abi/type_test.go
+++ b/accounts/abi/type_test.go
@@ -0,0 +1,280 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package abi
+
+import (
+	"math/big"
+	"reflect"
+	"testing"
+
+	"github.com/davecgh/go-spew/spew"
+	"github.com/ethereum/go-ethereum/common"
+)
+
+// typeWithoutStringer is a alias for the Type type which simply doesn't implement
+// the stringer interface to allow printing type details in the tests below.
+type typeWithoutStringer Type
+
+// Tests that all allowed types get recognized by the type parser.
+func TestTypeRegexp(t *testing.T) {
+	tests := []struct {
+		blob string
+		kind Type
+	}{
+		{"bool", Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}},
+		{"bool[]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]bool(nil)), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[]"}},
+		{"bool[2]", Type{Size: 2, Kind: reflect.Array, T: ArrayTy, Type: reflect.TypeOf([2]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[2]"}},
+		{"bool[2][]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([][2]bool{}), Elem: &Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[2]"}, stringKind: "bool[2][]"}},
+		{"bool[][]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([][]bool{}), Elem: &Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[]"}, stringKind: "bool[][]"}},
+		{"bool[][2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2][]bool{}), Elem: &Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[]"}, stringKind: "bool[][2]"}},
+		{"bool[2][2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2][2]bool{}), Elem: &Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[2]"}, stringKind: "bool[2][2]"}},
+		{"bool[2][][2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2][][2]bool{}), Elem: &Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([][2]bool{}), Elem: &Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[2]"}, stringKind: "bool[2][]"}, stringKind: "bool[2][][2]"}},
+		{"bool[2][2][2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2][2][2]bool{}), Elem: &Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2][2]bool{}), Elem: &Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[2]"}, stringKind: "bool[2][2]"}, stringKind: "bool[2][2][2]"}},
+		{"bool[][][]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([][][]bool{}), Elem: &Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([][]bool{}), Elem: &Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[]"}, stringKind: "bool[][]"}, stringKind: "bool[][][]"}},
+		{"bool[][2][]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([][2][]bool{}), Elem: &Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2][]bool{}), Elem: &Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([]bool{}), Elem: &Type{Kind: reflect.Bool, T: BoolTy, Type: reflect.TypeOf(bool(false)), stringKind: "bool"}, stringKind: "bool[]"}, stringKind: "bool[][2]"}, stringKind: "bool[][2][]"}},
+		{"int8", Type{Kind: reflect.Int8, Type: int8_t, Size: 8, T: IntTy, stringKind: "int8"}},
+		{"int16", Type{Kind: reflect.Int16, Type: int16_t, Size: 16, T: IntTy, stringKind: "int16"}},
+		{"int32", Type{Kind: reflect.Int32, Type: int32_t, Size: 32, T: IntTy, stringKind: "int32"}},
+		{"int64", Type{Kind: reflect.Int64, Type: int64_t, Size: 64, T: IntTy, stringKind: "int64"}},
+		{"int256", Type{Kind: reflect.Ptr, Type: big_t, Size: 256, T: IntTy, stringKind: "int256"}},
+		{"int8[]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]int8{}), Elem: &Type{Kind: reflect.Int8, Type: int8_t, Size: 8, T: IntTy, stringKind: "int8"}, stringKind: "int8[]"}},
+		{"int8[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]int8{}), Elem: &Type{Kind: reflect.Int8, Type: int8_t, Size: 8, T: IntTy, stringKind: "int8"}, stringKind: "int8[2]"}},
+		{"int16[]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]int16{}), Elem: &Type{Kind: reflect.Int16, Type: int16_t, Size: 16, T: IntTy, stringKind: "int16"}, stringKind: "int16[]"}},
+		{"int16[2]", Type{Size: 2, Kind: reflect.Array, T: ArrayTy, Type: reflect.TypeOf([2]int16{}), Elem: &Type{Kind: reflect.Int16, Type: int16_t, Size: 16, T: IntTy, stringKind: "int16"}, stringKind: "int16[2]"}},
+		{"int32[]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]int32{}), Elem: &Type{Kind: reflect.Int32, Type: int32_t, Size: 32, T: IntTy, stringKind: "int32"}, stringKind: "int32[]"}},
+		{"int32[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]int32{}), Elem: &Type{Kind: reflect.Int32, Type: int32_t, Size: 32, T: IntTy, stringKind: "int32"}, stringKind: "int32[2]"}},
+		{"int64[]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]int64{}), Elem: &Type{Kind: reflect.Int64, Type: int64_t, Size: 64, T: IntTy, stringKind: "int64"}, stringKind: "int64[]"}},
+		{"int64[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]int64{}), Elem: &Type{Kind: reflect.Int64, Type: int64_t, Size: 64, T: IntTy, stringKind: "int64"}, stringKind: "int64[2]"}},
+		{"int256[]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]*big.Int{}), Elem: &Type{Kind: reflect.Ptr, Type: big_t, Size: 256, T: IntTy, stringKind: "int256"}, stringKind: "int256[]"}},
+		{"int256[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]*big.Int{}), Elem: &Type{Kind: reflect.Ptr, Type: big_t, Size: 256, T: IntTy, stringKind: "int256"}, stringKind: "int256[2]"}},
+		{"uint8", Type{Kind: reflect.Uint8, Type: uint8_t, Size: 8, T: UintTy, stringKind: "uint8"}},
+		{"uint16", Type{Kind: reflect.Uint16, Type: uint16_t, Size: 16, T: UintTy, stringKind: "uint16"}},
+		{"uint32", Type{Kind: reflect.Uint32, Type: uint32_t, Size: 32, T: UintTy, stringKind: "uint32"}},
+		{"uint64", Type{Kind: reflect.Uint64, Type: uint64_t, Size: 64, T: UintTy, stringKind: "uint64"}},
+		{"uint256", Type{Kind: reflect.Ptr, Type: big_t, Size: 256, T: UintTy, stringKind: "uint256"}},
+		{"uint8[]", Type{Kind: reflect.Slice, T: SliceTy, Type: reflect.TypeOf([]uint8{}), Elem: &Type{Kind: reflect.Uint8, Type: uint8_t, Size: 8, T: UintTy, stringKind: "uint8"}, stringKind: "uint8[]"}},
+		{"uint8[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]uint8{}), Elem: &Type{Kind: reflect.Uint8, Type: uint8_t, Size: 8, T: UintTy, stringKind: "uint8"}, stringKind: "uint8[2]"}},
+		{"uint16[]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([]uint16{}), Elem: &Type{Kind: reflect.Uint16, Type: uint16_t, Size: 16, T: UintTy, stringKind: "uint16"}, stringKind: "uint16[]"}},
+		{"uint16[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]uint16{}), Elem: &Type{Kind: reflect.Uint16, Type: uint16_t, Size: 16, T: UintTy, stringKind: "uint16"}, stringKind: "uint16[2]"}},
+		{"uint32[]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([]uint32{}), Elem: &Type{Kind: reflect.Uint32, Type: uint32_t, Size: 32, T: UintTy, stringKind: "uint32"}, stringKind: "uint32[]"}},
+		{"uint32[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]uint32{}), Elem: &Type{Kind: reflect.Uint32, Type: uint32_t, Size: 32, T: UintTy, stringKind: "uint32"}, stringKind: "uint32[2]"}},
+		{"uint64[]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([]uint64{}), Elem: &Type{Kind: reflect.Uint64, Type: uint64_t, Size: 64, T: UintTy, stringKind: "uint64"}, stringKind: "uint64[]"}},
+		{"uint64[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]uint64{}), Elem: &Type{Kind: reflect.Uint64, Type: uint64_t, Size: 64, T: UintTy, stringKind: "uint64"}, stringKind: "uint64[2]"}},
+		{"uint256[]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([]*big.Int{}), Elem: &Type{Kind: reflect.Ptr, Type: big_t, Size: 256, T: UintTy, stringKind: "uint256"}, stringKind: "uint256[]"}},
+		{"uint256[2]", Type{Kind: reflect.Array, T: ArrayTy, Type: reflect.TypeOf([2]*big.Int{}), Size: 2, Elem: &Type{Kind: reflect.Ptr, Type: big_t, Size: 256, T: UintTy, stringKind: "uint256"}, stringKind: "uint256[2]"}},
+		{"bytes32", Type{Kind: reflect.Array, T: FixedBytesTy, Size: 32, Type: reflect.TypeOf([32]byte{}), stringKind: "bytes32"}},
+		{"bytes[]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([][]byte{}), Elem: &Type{Kind: reflect.Slice, Type: reflect.TypeOf([]byte{}), T: BytesTy, stringKind: "bytes"}, stringKind: "bytes[]"}},
+		{"bytes[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2][]byte{}), Elem: &Type{T: BytesTy, Type: reflect.TypeOf([]byte{}), Kind: reflect.Slice, stringKind: "bytes"}, stringKind: "bytes[2]"}},
+		{"bytes32[]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([][32]byte{}), Elem: &Type{Kind: reflect.Array, Type: reflect.TypeOf([32]byte{}), T: FixedBytesTy, Size: 32, stringKind: "bytes32"}, stringKind: "bytes32[]"}},
+		{"bytes32[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2][32]byte{}), Elem: &Type{Kind: reflect.Array, T: FixedBytesTy, Size: 32, Type: reflect.TypeOf([32]byte{}), stringKind: "bytes32"}, stringKind: "bytes32[2]"}},
+		{"string", Type{Kind: reflect.String, T: StringTy, Type: reflect.TypeOf(""), stringKind: "string"}},
+		{"string[]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([]string{}), Elem: &Type{Kind: reflect.String, Type: reflect.TypeOf(""), T: StringTy, stringKind: "string"}, stringKind: "string[]"}},
+		{"string[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]string{}), Elem: &Type{Kind: reflect.String, T: StringTy, Type: reflect.TypeOf(""), stringKind: "string"}, stringKind: "string[2]"}},
+		{"address", Type{Kind: reflect.Array, Type: address_t, Size: 20, T: AddressTy, stringKind: "address"}},
+		{"address[]", Type{T: SliceTy, Kind: reflect.Slice, Type: reflect.TypeOf([]common.Address{}), Elem: &Type{Kind: reflect.Array, Type: address_t, Size: 20, T: AddressTy, stringKind: "address"}, stringKind: "address[]"}},
+		{"address[2]", Type{Kind: reflect.Array, T: ArrayTy, Size: 2, Type: reflect.TypeOf([2]common.Address{}), Elem: &Type{Kind: reflect.Array, Type: address_t, Size: 20, T: AddressTy, stringKind: "address"}, stringKind: "address[2]"}},
+		// TODO when fixed types are implemented properly
+		// {"fixed", Type{}},
+		// {"fixed128x128", Type{}},
+		// {"fixed[]", Type{}},
+		// {"fixed[2]", Type{}},
+		// {"fixed128x128[]", Type{}},
+		// {"fixed128x128[2]", Type{}},
+	}
+
+	for _, tt := range tests {
+		typ, err := NewType(tt.blob)
+		if err != nil {
+			t.Errorf("type %q: failed to parse type string: %v", tt.blob, err)
+		}
+		if !reflect.DeepEqual(typ, tt.kind) {
+			t.Errorf("type %q: parsed type mismatch:\nGOT %s\nWANT %s ", tt.blob, spew.Sdump(typeWithoutStringer(typ)), spew.Sdump(typeWithoutStringer(tt.kind)))
+		}
+	}
+}
+
+func TestTypeCheck(t *testing.T) {
+	for i, test := range []struct {
+		typ   string
+		input interface{}
+		err   string
+	}{
+		{"uint", big.NewInt(1), "unsupported arg type: uint"},
+		{"int", big.NewInt(1), "unsupported arg type: int"},
+		{"uint256", big.NewInt(1), ""},
+		{"uint256[][3][]", [][3][]*big.Int{{{}}}, ""},
+		{"uint256[][][3]", [3][][]*big.Int{{{}}}, ""},
+		{"uint256[3][][]", [][][3]*big.Int{{{}}}, ""},
+		{"uint256[3][3][3]", [3][3][3]*big.Int{{{}}}, ""},
+		{"uint8[][]", [][]uint8{}, ""},
+		{"int256", big.NewInt(1), ""},
+		{"uint8", uint8(1), ""},
+		{"uint16", uint16(1), ""},
+		{"uint32", uint32(1), ""},
+		{"uint64", uint64(1), ""},
+		{"int8", int8(1), ""},
+		{"int16", int16(1), ""},
+		{"int32", int32(1), ""},
+		{"int64", int64(1), ""},
+		{"uint24", big.NewInt(1), ""},
+		{"uint40", big.NewInt(1), ""},
+		{"uint48", big.NewInt(1), ""},
+		{"uint56", big.NewInt(1), ""},
+		{"uint72", big.NewInt(1), ""},
+		{"uint80", big.NewInt(1), ""},
+		{"uint88", big.NewInt(1), ""},
+		{"uint96", big.NewInt(1), ""},
+		{"uint104", big.NewInt(1), ""},
+		{"uint112", big.NewInt(1), ""},
+		{"uint120", big.NewInt(1), ""},
+		{"uint128", big.NewInt(1), ""},
+		{"uint136", big.NewInt(1), ""},
+		{"uint144", big.NewInt(1), ""},
+		{"uint152", big.NewInt(1), ""},
+		{"uint160", big.NewInt(1), ""},
+		{"uint168", big.NewInt(1), ""},
+		{"uint176", big.NewInt(1), ""},
+		{"uint184", big.NewInt(1), ""},
+		{"uint192", big.NewInt(1), ""},
+		{"uint200", big.NewInt(1), ""},
+		{"uint208", big.NewInt(1), ""},
+		{"uint216", big.NewInt(1), ""},
+		{"uint224", big.NewInt(1), ""},
+		{"uint232", big.NewInt(1), ""},
+		{"uint240", big.NewInt(1), ""},
+		{"uint248", big.NewInt(1), ""},
+		{"int24", big.NewInt(1), ""},
+		{"int40", big.NewInt(1), ""},
+		{"int48", big.NewInt(1), ""},
+		{"int56", big.NewInt(1), ""},
+		{"int72", big.NewInt(1), ""},
+		{"int80", big.NewInt(1), ""},
+		{"int88", big.NewInt(1), ""},
+		{"int96", big.NewInt(1), ""},
+		{"int104", big.NewInt(1), ""},
+		{"int112", big.NewInt(1), ""},
+		{"int120", big.NewInt(1), ""},
+		{"int128", big.NewInt(1), ""},
+		{"int136", big.NewInt(1), ""},
+		{"int144", big.NewInt(1), ""},
+		{"int152", big.NewInt(1), ""},
+		{"int160", big.NewInt(1), ""},
+		{"int168", big.NewInt(1), ""},
+		{"int176", big.NewInt(1), ""},
+		{"int184", big.NewInt(1), ""},
+		{"int192", big.NewInt(1), ""},
+		{"int200", big.NewInt(1), ""},
+		{"int208", big.NewInt(1), ""},
+		{"int216", big.NewInt(1), ""},
+		{"int224", big.NewInt(1), ""},
+		{"int232", big.NewInt(1), ""},
+		{"int240", big.NewInt(1), ""},
+		{"int248", big.NewInt(1), ""},
+		{"uint30", uint8(1), "abi: cannot use uint8 as type ptr as argument"},
+		{"uint8", uint16(1), "abi: cannot use uint16 as type uint8 as argument"},
+		{"uint8", uint32(1), "abi: cannot use uint32 as type uint8 as argument"},
+		{"uint8", uint64(1), "abi: cannot use uint64 as type uint8 as argument"},
+		{"uint8", int8(1), "abi: cannot use int8 as type uint8 as argument"},
+		{"uint8", int16(1), "abi: cannot use int16 as type uint8 as argument"},
+		{"uint8", int32(1), "abi: cannot use int32 as type uint8 as argument"},
+		{"uint8", int64(1), "abi: cannot use int64 as type uint8 as argument"},
+		{"uint16", uint16(1), ""},
+		{"uint16", uint8(1), "abi: cannot use uint8 as type uint16 as argument"},
+		{"uint16[]", []uint16{1, 2, 3}, ""},
+		{"uint16[]", [3]uint16{1, 2, 3}, ""},
+		{"uint16[]", []uint32{1, 2, 3}, "abi: cannot use []uint32 as type [0]uint16 as argument"},
+		{"uint16[3]", [3]uint32{1, 2, 3}, "abi: cannot use [3]uint32 as type [3]uint16 as argument"},
+		{"uint16[3]", [4]uint16{1, 2, 3}, "abi: cannot use [4]uint16 as type [3]uint16 as argument"},
+		{"uint16[3]", []uint16{1, 2, 3}, ""},
+		{"uint16[3]", []uint16{1, 2, 3, 4}, "abi: cannot use [4]uint16 as type [3]uint16 as argument"},
+		{"address[]", []common.Address{{1}}, ""},
+		{"address[1]", []common.Address{{1}}, ""},
+		{"address[1]", [1]common.Address{{1}}, ""},
+		{"address[2]", [1]common.Address{{1}}, "abi: cannot use [1]array as type [2]array as argument"},
+		{"bytes32", [32]byte{}, ""},
+		{"bytes31", [31]byte{}, ""},
+		{"bytes30", [30]byte{}, ""},
+		{"bytes29", [29]byte{}, ""},
+		{"bytes28", [28]byte{}, ""},
+		{"bytes27", [27]byte{}, ""},
+		{"bytes26", [26]byte{}, ""},
+		{"bytes25", [25]byte{}, ""},
+		{"bytes24", [24]byte{}, ""},
+		{"bytes23", [23]byte{}, ""},
+		{"bytes22", [22]byte{}, ""},
+		{"bytes21", [21]byte{}, ""},
+		{"bytes20", [20]byte{}, ""},
+		{"bytes19", [19]byte{}, ""},
+		{"bytes18", [18]byte{}, ""},
+		{"bytes17", [17]byte{}, ""},
+		{"bytes16", [16]byte{}, ""},
+		{"bytes15", [15]byte{}, ""},
+		{"bytes14", [14]byte{}, ""},
+		{"bytes13", [13]byte{}, ""},
+		{"bytes12", [12]byte{}, ""},
+		{"bytes11", [11]byte{}, ""},
+		{"bytes10", [10]byte{}, ""},
+		{"bytes9", [9]byte{}, ""},
+		{"bytes8", [8]byte{}, ""},
+		{"bytes7", [7]byte{}, ""},
+		{"bytes6", [6]byte{}, ""},
+		{"bytes5", [5]byte{}, ""},
+		{"bytes4", [4]byte{}, ""},
+		{"bytes3", [3]byte{}, ""},
+		{"bytes2", [2]byte{}, ""},
+		{"bytes1", [1]byte{}, ""},
+		{"bytes32", [33]byte{}, "abi: cannot use [33]uint8 as type [32]uint8 as argument"},
+		{"bytes32", common.Hash{1}, ""},
+		{"bytes31", common.Hash{1}, "abi: cannot use common.Hash as type [31]uint8 as argument"},
+		{"bytes31", [32]byte{}, "abi: cannot use [32]uint8 as type [31]uint8 as argument"},
+		{"bytes", []byte{0, 1}, ""},
+		{"bytes", [2]byte{0, 1}, "abi: cannot use array as type slice as argument"},
+		{"bytes", common.Hash{1}, "abi: cannot use array as type slice as argument"},
+		{"string", "hello world", ""},
+		{"string", string(""), ""},
+		{"string", []byte{}, "abi: cannot use slice as type string as argument"},
+		{"bytes32[]", [][32]byte{{}}, ""},
+		{"function", [24]byte{}, ""},
+		{"bytes20", common.Address{}, ""},
+		{"address", [20]byte{}, ""},
+		{"address", common.Address{}, ""},
+	} {
+		typ, err := NewType(test.typ)
+		if err != nil && len(test.err) == 0 {
+			t.Fatal("unexpected parse error:", err)
+		} else if err != nil && len(test.err) != 0 {
+			if err.Error() != test.err {
+				t.Errorf("%d failed. Expected err: '%v' got err: '%v'", i, test.err, err)
+			}
+			continue
+		}
+
+		err = typeCheck(typ, reflect.ValueOf(test.input))
+		if err != nil && len(test.err) == 0 {
+			t.Errorf("%d failed. Expected no err but got: %v", i, err)
+			continue
+		}
+		if err == nil && len(test.err) != 0 {
+			t.Errorf("%d failed. Expected err: %v but got none", i, test.err)
+			continue
+		}
+
+		if err != nil && len(test.err) != 0 && err.Error() != test.err {
+			t.Errorf("%d failed. Expected err: '%v' got err: '%v'", i, test.err, err)
+		}
+	}
+}
--- a/accounts/abi/unpack.go
+++ b/accounts/abi/unpack.go
@@ -0,0 +1,230 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package abi
+
+import (
+	"encoding/binary"
+	"fmt"
+	"math/big"
+	"reflect"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+// reads the integer based on its kind
+func readInteger(kind reflect.Kind, b []byte) interface{} {
+	switch kind {
+	case reflect.Uint8:
+		return b[len(b)-1]
+	case reflect.Uint16:
+		return binary.BigEndian.Uint16(b[len(b)-2:])
+	case reflect.Uint32:
+		return binary.BigEndian.Uint32(b[len(b)-4:])
+	case reflect.Uint64:
+		return binary.BigEndian.Uint64(b[len(b)-8:])
+	case reflect.Int8:
+		return int8(b[len(b)-1])
+	case reflect.Int16:
+		return int16(binary.BigEndian.Uint16(b[len(b)-2:]))
+	case reflect.Int32:
+		return int32(binary.BigEndian.Uint32(b[len(b)-4:]))
+	case reflect.Int64:
+		return int64(binary.BigEndian.Uint64(b[len(b)-8:]))
+	default:
+		return new(big.Int).SetBytes(b)
+	}
+}
+
+// reads a bool
+func readBool(word []byte) (bool, error) {
+	for _, b := range word[:31] {
+		if b != 0 {
+			return false, errBadBool
+		}
+	}
+	switch word[31] {
+	case 0:
+		return false, nil
+	case 1:
+		return true, nil
+	default:
+		return false, errBadBool
+	}
+}
+
+// A function type is simply the address with the function selection signature at the end.
+// This enforces that standard by always presenting it as a 24-array (address + sig = 24 bytes)
+func readFunctionType(t Type, word []byte) (funcTy [24]byte, err error) {
+	if t.T != FunctionTy {
+		return [24]byte{}, fmt.Errorf("abi: invalid type in call to make function type byte array")
+	}
+	if garbage := binary.BigEndian.Uint64(word[24:32]); garbage != 0 {
+		err = fmt.Errorf("abi: got improperly encoded function type, got %v", word)
+	} else {
+		copy(funcTy[:], word[0:24])
+	}
+	return
+}
+
+// through reflection, creates a fixed array to be read from
+func readFixedBytes(t Type, word []byte) (interface{}, error) {
+	if t.T != FixedBytesTy {
+		return nil, fmt.Errorf("abi: invalid type in call to make fixed byte array")
+	}
+	// convert
+	array := reflect.New(t.Type).Elem()
+
+	reflect.Copy(array, reflect.ValueOf(word[0:t.Size]))
+	return array.Interface(), nil
+
+}
+
+func getFullElemSize(elem *Type) int {
+	//all other should be counted as 32 (slices have pointers to respective elements)
+	size := 32
+	//arrays wrap it, each element being the same size
+	for elem.T == ArrayTy {
+		size *= elem.Size
+		elem = elem.Elem
+	}
+	return size
+}
+
+// iteratively unpack elements
+func forEachUnpack(t Type, output []byte, start, size int) (interface{}, error) {
+	if size < 0 {
+		return nil, fmt.Errorf("cannot marshal input to array, size is negative (%d)", size)
+	}
+	if start+32*size > len(output) {
+		return nil, fmt.Errorf("abi: cannot marshal in to go array: offset %d would go over slice boundary (len=%d)", len(output), start+32*size)
+	}
+
+	// this value will become our slice or our array, depending on the type
+	var refSlice reflect.Value
+
+	if t.T == SliceTy {
+		// declare our slice
+		refSlice = reflect.MakeSlice(t.Type, size, size)
+	} else if t.T == ArrayTy {
+		// declare our array
+		refSlice = reflect.New(t.Type).Elem()
+	} else {
+		return nil, fmt.Errorf("abi: invalid type in array/slice unpacking stage")
+	}
+
+	// Arrays have packed elements, resulting in longer unpack steps.
+	// Slices have just 32 bytes per element (pointing to the contents).
+	elemSize := 32
+	if t.T == ArrayTy {
+		elemSize = getFullElemSize(t.Elem)
+	}
+
+	for i, j := start, 0; j < size; i, j = i+elemSize, j+1 {
+
+		inter, err := toGoType(i, *t.Elem, output)
+		if err != nil {
+			return nil, err
+		}
+
+		// append the item to our reflect slice
+		refSlice.Index(j).Set(reflect.ValueOf(inter))
+	}
+
+	// return the interface
+	return refSlice.Interface(), nil
+}
+
+// toGoType parses the output bytes and recursively assigns the value of these bytes
+// into a go type with accordance with the ABI spec.
+func toGoType(index int, t Type, output []byte) (interface{}, error) {
+	if index+32 > len(output) {
+		return nil, fmt.Errorf("abi: cannot marshal in to go type: length insufficient %d require %d", len(output), index+32)
+	}
+
+	var (
+		returnOutput []byte
+		begin, end   int
+		err          error
+	)
+
+	// if we require a length prefix, find the beginning word and size returned.
+	if t.requiresLengthPrefix() {
+		begin, end, err = lengthPrefixPointsTo(index, output)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		returnOutput = output[index : index+32]
+	}
+
+	switch t.T {
+	case SliceTy:
+		return forEachUnpack(t, output, begin, end)
+	case ArrayTy:
+		return forEachUnpack(t, output, index, t.Size)
+	case StringTy: // variable arrays are written at the end of the return bytes
+		return string(output[begin : begin+end]), nil
+	case IntTy, UintTy:
+		return readInteger(t.Kind, returnOutput), nil
+	case BoolTy:
+		return readBool(returnOutput)
+	case AddressTy:
+		return common.BytesToAddress(returnOutput), nil
+	case HashTy:
+		return common.BytesToHash(returnOutput), nil
+	case BytesTy:
+		return output[begin : begin+end], nil
+	case FixedBytesTy:
+		return readFixedBytes(t, returnOutput)
+	case FunctionTy:
+		return readFunctionType(t, returnOutput)
+	default:
+		return nil, fmt.Errorf("abi: unknown type %v", t.T)
+	}
+}
+
+// interprets a 32 byte slice as an offset and then determines which indice to look to decode the type.
+func lengthPrefixPointsTo(index int, output []byte) (start int, length int, err error) {
+	bigOffsetEnd := big.NewInt(0).SetBytes(output[index : index+32])
+	bigOffsetEnd.Add(bigOffsetEnd, common.Big32)
+	outputLength := big.NewInt(int64(len(output)))
+
+	if bigOffsetEnd.Cmp(outputLength) > 0 {
+		return 0, 0, fmt.Errorf("abi: cannot marshal in to go slice: offset %v would go over slice boundary (len=%v)", bigOffsetEnd, outputLength)
+	}
+
+	if bigOffsetEnd.BitLen() > 63 {
+		return 0, 0, fmt.Errorf("abi offset larger than int64: %v", bigOffsetEnd)
+	}
+
+	offsetEnd := int(bigOffsetEnd.Uint64())
+	lengthBig := big.NewInt(0).SetBytes(output[offsetEnd-32 : offsetEnd])
+
+	totalSize := big.NewInt(0)
+	totalSize.Add(totalSize, bigOffsetEnd)
+	totalSize.Add(totalSize, lengthBig)
+	if totalSize.BitLen() > 63 {
+		return 0, 0, fmt.Errorf("abi length larger than int64: %v", totalSize)
+	}
+
+	if totalSize.Cmp(outputLength) > 0 {
+		return 0, 0, fmt.Errorf("abi: cannot marshal in to go type: length insufficient %v require %v", outputLength, totalSize)
+	}
+	start = int(bigOffsetEnd.Uint64())
+	length = int(lengthBig.Uint64())
+	return
+}
--- a/accounts/abi/unpack_test.go
+++ b/accounts/abi/unpack_test.go
@@ -0,0 +1,800 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package abi
+
+import (
+	"bytes"
+	"encoding/hex"
+	"fmt"
+	"math/big"
+	"reflect"
+	"strconv"
+	"strings"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/stretchr/testify/require"
+)
+
+type unpackTest struct {
+	def  string      // ABI definition JSON
+	enc  string      // evm return data
+	want interface{} // the expected output
+	err  string      // empty or error if expected
+}
+
+func (test unpackTest) checkError(err error) error {
+	if err != nil {
+		if len(test.err) == 0 {
+			return fmt.Errorf("expected no err but got: %v", err)
+		} else if err.Error() != test.err {
+			return fmt.Errorf("expected err: '%v' got err: %q", test.err, err)
+		}
+	} else if len(test.err) > 0 {
+		return fmt.Errorf("expected err: %v but got none", test.err)
+	}
+	return nil
+}
+
+var unpackTests = []unpackTest{
+	{
+		def:  `[{ "type": "bool" }]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: true,
+	},
+	{
+		def:  `[{"type": "uint32"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: uint32(1),
+	},
+	{
+		def:  `[{"type": "uint32"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: uint16(0),
+		err:  "abi: cannot unmarshal uint32 in to uint16",
+	},
+	{
+		def:  `[{"type": "uint17"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: uint16(0),
+		err:  "abi: cannot unmarshal *big.Int in to uint16",
+	},
+	{
+		def:  `[{"type": "uint17"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: big.NewInt(1),
+	},
+	{
+		def:  `[{"type": "int32"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: int32(1),
+	},
+	{
+		def:  `[{"type": "int32"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: int16(0),
+		err:  "abi: cannot unmarshal int32 in to int16",
+	},
+	{
+		def:  `[{"type": "int17"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: int16(0),
+		err:  "abi: cannot unmarshal *big.Int in to int16",
+	},
+	{
+		def:  `[{"type": "int17"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001",
+		want: big.NewInt(1),
+	},
+	{
+		def:  `[{"type": "address"}]`,
+		enc:  "0000000000000000000000000100000000000000000000000000000000000000",
+		want: common.Address{1},
+	},
+	{
+		def:  `[{"type": "bytes32"}]`,
+		enc:  "0100000000000000000000000000000000000000000000000000000000000000",
+		want: [32]byte{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	},
+	{
+		def:  `[{"type": "bytes"}]`,
+		enc:  "000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000",
+		want: common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
+	},
+	{
+		def:  `[{"type": "bytes"}]`,
+		enc:  "000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000",
+		want: [32]byte{},
+		err:  "abi: cannot unmarshal []uint8 in to [32]uint8",
+	},
+	{
+		def:  `[{"type": "bytes32"}]`,
+		enc:  "000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000",
+		want: []byte(nil),
+		err:  "abi: cannot unmarshal [32]uint8 in to []uint8",
+	},
+	{
+		def:  `[{"type": "bytes32"}]`,
+		enc:  "0100000000000000000000000000000000000000000000000000000000000000",
+		want: [32]byte{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	},
+	{
+		def:  `[{"type": "function"}]`,
+		enc:  "0100000000000000000000000000000000000000000000000000000000000000",
+		want: [24]byte{1},
+	},
+	// slices
+	{
+		def:  `[{"type": "uint8[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []uint8{1, 2},
+	},
+	{
+		def:  `[{"type": "uint8[2]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2]uint8{1, 2},
+	},
+	// multi dimensional, if these pass, all types that don't require length prefix should pass
+	{
+		def:  `[{"type": "uint8[][]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000E0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [][]uint8{{1, 2}, {1, 2}},
+	},
+	{
+		def:  `[{"type": "uint8[2][2]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2][2]uint8{{1, 2}, {1, 2}},
+	},
+	{
+		def:  `[{"type": "uint8[][2]"}]`,
+		enc:  "000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000001",
+		want: [2][]uint8{{1}, {1}},
+	},
+	{
+		def:  `[{"type": "uint8[2][]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [][2]uint8{{1, 2}},
+	},
+	{
+		def:  `[{"type": "uint16[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []uint16{1, 2},
+	},
+	{
+		def:  `[{"type": "uint16[2]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2]uint16{1, 2},
+	},
+	{
+		def:  `[{"type": "uint32[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []uint32{1, 2},
+	},
+	{
+		def:  `[{"type": "uint32[2]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2]uint32{1, 2},
+	},
+	{
+		def:  `[{"type": "uint32[2][3][4]"}]`,
+		enc:  "000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000700000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000f000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000110000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000000000000001300000000000000000000000000000000000000000000000000000000000000140000000000000000000000000000000000000000000000000000000000000015000000000000000000000000000000000000000000000000000000000000001600000000000000000000000000000000000000000000000000000000000000170000000000000000000000000000000000000000000000000000000000000018",
+		want: [4][3][2]uint32{{{1, 2}, {3, 4}, {5, 6}}, {{7, 8}, {9, 10}, {11, 12}}, {{13, 14}, {15, 16}, {17, 18}}, {{19, 20}, {21, 22}, {23, 24}}},
+	},
+	{
+		def:  `[{"type": "uint64[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []uint64{1, 2},
+	},
+	{
+		def:  `[{"type": "uint64[2]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2]uint64{1, 2},
+	},
+	{
+		def:  `[{"type": "uint256[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []*big.Int{big.NewInt(1), big.NewInt(2)},
+	},
+	{
+		def:  `[{"type": "uint256[3]"}]`,
+		enc:  "000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003",
+		want: [3]*big.Int{big.NewInt(1), big.NewInt(2), big.NewInt(3)},
+	},
+	{
+		def:  `[{"type": "int8[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []int8{1, 2},
+	},
+	{
+		def:  `[{"type": "int8[2]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2]int8{1, 2},
+	},
+	{
+		def:  `[{"type": "int16[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []int16{1, 2},
+	},
+	{
+		def:  `[{"type": "int16[2]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2]int16{1, 2},
+	},
+	{
+		def:  `[{"type": "int32[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []int32{1, 2},
+	},
+	{
+		def:  `[{"type": "int32[2]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2]int32{1, 2},
+	},
+	{
+		def:  `[{"type": "int64[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []int64{1, 2},
+	},
+	{
+		def:  `[{"type": "int64[2]"}]`,
+		enc:  "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: [2]int64{1, 2},
+	},
+	{
+		def:  `[{"type": "int256[]"}]`,
+		enc:  "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: []*big.Int{big.NewInt(1), big.NewInt(2)},
+	},
+	{
+		def:  `[{"type": "int256[3]"}]`,
+		enc:  "000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003",
+		want: [3]*big.Int{big.NewInt(1), big.NewInt(2), big.NewInt(3)},
+	},
+	// struct outputs
+	{
+		def: `[{"name":"int1","type":"int256"},{"name":"int2","type":"int256"}]`,
+		enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: struct {
+			Int1 *big.Int
+			Int2 *big.Int
+		}{big.NewInt(1), big.NewInt(2)},
+	},
+	{
+		def: `[{"name":"int","type":"int256"},{"name":"Int","type":"int256"}]`,
+		enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: struct {
+			Int1 *big.Int
+			Int2 *big.Int
+		}{},
+		err: "abi: multiple outputs mapping to the same struct field 'Int'",
+	},
+	{
+		def: `[{"name":"int","type":"int256"},{"name":"_int","type":"int256"}]`,
+		enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: struct {
+			Int1 *big.Int
+			Int2 *big.Int
+		}{},
+		err: "abi: multiple outputs mapping to the same struct field 'Int'",
+	},
+	{
+		def: `[{"name":"Int","type":"int256"},{"name":"_int","type":"int256"}]`,
+		enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: struct {
+			Int1 *big.Int
+			Int2 *big.Int
+		}{},
+		err: "abi: multiple outputs mapping to the same struct field 'Int'",
+	},
+	{
+		def: `[{"name":"Int","type":"int256"},{"name":"_","type":"int256"}]`,
+		enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		want: struct {
+			Int1 *big.Int
+			Int2 *big.Int
+		}{},
+		err: "abi: purely underscored output cannot unpack to struct",
+	},
+}
+
+func TestUnpack(t *testing.T) {
+	for i, test := range unpackTests {
+		t.Run(strconv.Itoa(i), func(t *testing.T) {
+			def := fmt.Sprintf(`[{ "name" : "method", "outputs": %s}]`, test.def)
+			abi, err := JSON(strings.NewReader(def))
+			if err != nil {
+				t.Fatalf("invalid ABI definition %s: %v", def, err)
+			}
+			encb, err := hex.DecodeString(test.enc)
+			if err != nil {
+				t.Fatalf("invalid hex: %s" + test.enc)
+			}
+			outptr := reflect.New(reflect.TypeOf(test.want))
+			err = abi.Unpack(outptr.Interface(), "method", encb)
+			if err := test.checkError(err); err != nil {
+				t.Errorf("test %d (%v) failed: %v", i, test.def, err)
+				return
+			}
+			out := outptr.Elem().Interface()
+			if !reflect.DeepEqual(test.want, out) {
+				t.Errorf("test %d (%v) failed: expected %v, got %v", i, test.def, test.want, out)
+			}
+		})
+	}
+}
+
+type methodMultiOutput struct {
+	Int    *big.Int
+	String string
+}
+
+func methodMultiReturn(require *require.Assertions) (ABI, []byte, methodMultiOutput) {
+	const definition = `[
+	{ "name" : "multi", "constant" : false, "outputs": [ { "name": "Int", "type": "uint256" }, { "name": "String", "type": "string" } ] }]`
+	var expected = methodMultiOutput{big.NewInt(1), "hello"}
+
+	abi, err := JSON(strings.NewReader(definition))
+	require.NoError(err)
+	// using buff to make the code readable
+	buff := new(bytes.Buffer)
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000005"))
+	buff.Write(common.RightPadBytes([]byte(expected.String), 32))
+	return abi, buff.Bytes(), expected
+}
+
+func TestMethodMultiReturn(t *testing.T) {
+	type reversed struct {
+		String string
+		Int    *big.Int
+	}
+
+	abi, data, expected := methodMultiReturn(require.New(t))
+	bigint := new(big.Int)
+	var testCases = []struct {
+		dest     interface{}
+		expected interface{}
+		error    string
+		name     string
+	}{{
+		&methodMultiOutput{},
+		&expected,
+		"",
+		"Can unpack into structure",
+	}, {
+		&reversed{},
+		&reversed{expected.String, expected.Int},
+		"",
+		"Can unpack into reversed structure",
+	}, {
+		&[]interface{}{&bigint, new(string)},
+		&[]interface{}{&expected.Int, &expected.String},
+		"",
+		"Can unpack into a slice",
+	}, {
+		&[2]interface{}{&bigint, new(string)},
+		&[2]interface{}{&expected.Int, &expected.String},
+		"",
+		"Can unpack into an array",
+	}, {
+		&[]interface{}{new(int), new(int)},
+		&[]interface{}{&expected.Int, &expected.String},
+		"abi: cannot unmarshal *big.Int in to int",
+		"Can not unpack into a slice with wrong types",
+	}, {
+		&[]interface{}{new(int)},
+		&[]interface{}{},
+		"abi: insufficient number of elements in the list/array for unpack, want 2, got 1",
+		"Can not unpack into a slice with wrong types",
+	}}
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			require := require.New(t)
+			err := abi.Unpack(tc.dest, "multi", data)
+			if tc.error == "" {
+				require.Nil(err, "Should be able to unpack method outputs.")
+				require.Equal(tc.expected, tc.dest)
+			} else {
+				require.EqualError(err, tc.error)
+			}
+		})
+	}
+}
+
+func TestMultiReturnWithArray(t *testing.T) {
+	const definition = `[{"name" : "multi", "outputs": [{"type": "uint64[3]"}, {"type": "uint64"}]}]`
+	abi, err := JSON(strings.NewReader(definition))
+	if err != nil {
+		t.Fatal(err)
+	}
+	buff := new(bytes.Buffer)
+	buff.Write(common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000900000000000000000000000000000000000000000000000000000000000000090000000000000000000000000000000000000000000000000000000000000009"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000008"))
+
+	ret1, ret1Exp := new([3]uint64), [3]uint64{9, 9, 9}
+	ret2, ret2Exp := new(uint64), uint64(8)
+	if err := abi.Unpack(&[]interface{}{ret1, ret2}, "multi", buff.Bytes()); err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(*ret1, ret1Exp) {
+		t.Error("array result", *ret1, "!= Expected", ret1Exp)
+	}
+	if *ret2 != ret2Exp {
+		t.Error("int result", *ret2, "!= Expected", ret2Exp)
+	}
+}
+
+func TestMultiReturnWithDeeplyNestedArray(t *testing.T) {
+	// Similar to TestMultiReturnWithArray, but with a special case in mind:
+	//  values of nested static arrays count towards the size as well, and any element following
+	//  after such nested array argument should be read with the correct offset,
+	//  so that it does not read content from the previous array argument.
+	const definition = `[{"name" : "multi", "outputs": [{"type": "uint64[3][2][4]"}, {"type": "uint64"}]}]`
+	abi, err := JSON(strings.NewReader(definition))
+	if err != nil {
+		t.Fatal(err)
+	}
+	buff := new(bytes.Buffer)
+	// construct the test array, each 3 char element is joined with 61 '0' chars,
+	// to from the ((3 + 61) * 0.5) = 32 byte elements in the array.
+	buff.Write(common.Hex2Bytes(strings.Join([]string{
+		"", //empty, to apply the 61-char separator to the first element as well.
+		"111", "112", "113", "121", "122", "123",
+		"211", "212", "213", "221", "222", "223",
+		"311", "312", "313", "321", "322", "323",
+		"411", "412", "413", "421", "422", "423",
+	}, "0000000000000000000000000000000000000000000000000000000000000")))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000009876"))
+
+	ret1, ret1Exp := new([4][2][3]uint64), [4][2][3]uint64{
+		{{0x111, 0x112, 0x113}, {0x121, 0x122, 0x123}},
+		{{0x211, 0x212, 0x213}, {0x221, 0x222, 0x223}},
+		{{0x311, 0x312, 0x313}, {0x321, 0x322, 0x323}},
+		{{0x411, 0x412, 0x413}, {0x421, 0x422, 0x423}},
+	}
+	ret2, ret2Exp := new(uint64), uint64(0x9876)
+	if err := abi.Unpack(&[]interface{}{ret1, ret2}, "multi", buff.Bytes()); err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(*ret1, ret1Exp) {
+		t.Error("array result", *ret1, "!= Expected", ret1Exp)
+	}
+	if *ret2 != ret2Exp {
+		t.Error("int result", *ret2, "!= Expected", ret2Exp)
+	}
+}
+
+func TestUnmarshal(t *testing.T) {
+	const definition = `[
+	{ "name" : "int", "constant" : false, "outputs": [ { "type": "uint256" } ] },
+	{ "name" : "bool", "constant" : false, "outputs": [ { "type": "bool" } ] },
+	{ "name" : "bytes", "constant" : false, "outputs": [ { "type": "bytes" } ] },
+	{ "name" : "fixed", "constant" : false, "outputs": [ { "type": "bytes32" } ] },
+	{ "name" : "multi", "constant" : false, "outputs": [ { "type": "bytes" }, { "type": "bytes" } ] },
+	{ "name" : "intArraySingle", "constant" : false, "outputs": [ { "type": "uint256[3]" } ] },
+	{ "name" : "addressSliceSingle", "constant" : false, "outputs": [ { "type": "address[]" } ] },
+	{ "name" : "addressSliceDouble", "constant" : false, "outputs": [ { "name": "a", "type": "address[]" }, { "name": "b", "type": "address[]" } ] },
+	{ "name" : "mixedBytes", "constant" : true, "outputs": [ { "name": "a", "type": "bytes" }, { "name": "b", "type": "bytes32" } ] }]`
+
+	abi, err := JSON(strings.NewReader(definition))
+	if err != nil {
+		t.Fatal(err)
+	}
+	buff := new(bytes.Buffer)
+
+	// marshall mixed bytes (mixedBytes)
+	p0, p0Exp := []byte{}, common.Hex2Bytes("01020000000000000000")
+	p1, p1Exp := [32]byte{}, common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000ddeeff")
+	mixedBytes := []interface{}{&p0, &p1}
+
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000ddeeff"))
+	buff.Write(common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000a"))
+	buff.Write(common.Hex2Bytes("0102000000000000000000000000000000000000000000000000000000000000"))
+
+	err = abi.Unpack(&mixedBytes, "mixedBytes", buff.Bytes())
+	if err != nil {
+		t.Error(err)
+	} else {
+		if !bytes.Equal(p0, p0Exp) {
+			t.Errorf("unexpected value unpacked: want %x, got %x", p0Exp, p0)
+		}
+
+		if !bytes.Equal(p1[:], p1Exp) {
+			t.Errorf("unexpected value unpacked: want %x, got %x", p1Exp, p1)
+		}
+	}
+
+	// marshal int
+	var Int *big.Int
+	err = abi.Unpack(&Int, "int", common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
+	if err != nil {
+		t.Error(err)
+	}
+
+	if Int == nil || Int.Cmp(big.NewInt(1)) != 0 {
+		t.Error("expected Int to be 1 got", Int)
+	}
+
+	// marshal bool
+	var Bool bool
+	err = abi.Unpack(&Bool, "bool", common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !Bool {
+		t.Error("expected Bool to be true")
+	}
+
+	// marshal dynamic bytes max length 32
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
+	bytesOut := common.RightPadBytes([]byte("hello"), 32)
+	buff.Write(bytesOut)
+
+	var Bytes []byte
+	err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !bytes.Equal(Bytes, bytesOut) {
+		t.Errorf("expected %x got %x", bytesOut, Bytes)
+	}
+
+	// marshall dynamic bytes max length 64
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040"))
+	bytesOut = common.RightPadBytes([]byte("hello"), 64)
+	buff.Write(bytesOut)
+
+	err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !bytes.Equal(Bytes, bytesOut) {
+		t.Errorf("expected %x got %x", bytesOut, Bytes)
+	}
+
+	// marshall dynamic bytes max length 64
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
+	buff.Write(common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000003f"))
+	bytesOut = common.RightPadBytes([]byte("hello"), 64)
+	buff.Write(bytesOut)
+
+	err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !bytes.Equal(Bytes, bytesOut[:len(bytesOut)-1]) {
+		t.Errorf("expected %x got %x", bytesOut[:len(bytesOut)-1], Bytes)
+	}
+
+	// marshal dynamic bytes output empty
+	err = abi.Unpack(&Bytes, "bytes", nil)
+	if err == nil {
+		t.Error("expected error")
+	}
+
+	// marshal dynamic bytes length 5
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000005"))
+	buff.Write(common.RightPadBytes([]byte("hello"), 32))
+
+	err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !bytes.Equal(Bytes, []byte("hello")) {
+		t.Errorf("expected %x got %x", bytesOut, Bytes)
+	}
+
+	// marshal dynamic bytes length 5
+	buff.Reset()
+	buff.Write(common.RightPadBytes([]byte("hello"), 32))
+
+	var hash common.Hash
+	err = abi.Unpack(&hash, "fixed", buff.Bytes())
+	if err != nil {
+		t.Error(err)
+	}
+
+	helloHash := common.BytesToHash(common.RightPadBytes([]byte("hello"), 32))
+	if hash != helloHash {
+		t.Errorf("Expected %x to equal %x", hash, helloHash)
+	}
+
+	// marshal error
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
+	err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
+	if err == nil {
+		t.Error("expected error")
+	}
+
+	err = abi.Unpack(&Bytes, "multi", make([]byte, 64))
+	if err == nil {
+		t.Error("expected error")
+	}
+
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000003"))
+	// marshal int array
+	var intArray [3]*big.Int
+	err = abi.Unpack(&intArray, "intArraySingle", buff.Bytes())
+	if err != nil {
+		t.Error(err)
+	}
+	var testAgainstIntArray [3]*big.Int
+	testAgainstIntArray[0] = big.NewInt(1)
+	testAgainstIntArray[1] = big.NewInt(2)
+	testAgainstIntArray[2] = big.NewInt(3)
+
+	for i, Int := range intArray {
+		if Int.Cmp(testAgainstIntArray[i]) != 0 {
+			t.Errorf("expected %v, got %v", testAgainstIntArray[i], Int)
+		}
+	}
+	// marshal address slice
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020")) // offset
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001")) // size
+	buff.Write(common.Hex2Bytes("0000000000000000000000000100000000000000000000000000000000000000"))
+
+	var outAddr []common.Address
+	err = abi.Unpack(&outAddr, "addressSliceSingle", buff.Bytes())
+	if err != nil {
+		t.Fatal("didn't expect error:", err)
+	}
+
+	if len(outAddr) != 1 {
+		t.Fatal("expected 1 item, got", len(outAddr))
+	}
+
+	if outAddr[0] != (common.Address{1}) {
+		t.Errorf("expected %x, got %x", common.Address{1}, outAddr[0])
+	}
+
+	// marshal multiple address slice
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040")) // offset
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000080")) // offset
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001")) // size
+	buff.Write(common.Hex2Bytes("0000000000000000000000000100000000000000000000000000000000000000"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002")) // size
+	buff.Write(common.Hex2Bytes("0000000000000000000000000200000000000000000000000000000000000000"))
+	buff.Write(common.Hex2Bytes("0000000000000000000000000300000000000000000000000000000000000000"))
+
+	var outAddrStruct struct {
+		A []common.Address
+		B []common.Address
+	}
+	err = abi.Unpack(&outAddrStruct, "addressSliceDouble", buff.Bytes())
+	if err != nil {
+		t.Fatal("didn't expect error:", err)
+	}
+
+	if len(outAddrStruct.A) != 1 {
+		t.Fatal("expected 1 item, got", len(outAddrStruct.A))
+	}
+
+	if outAddrStruct.A[0] != (common.Address{1}) {
+		t.Errorf("expected %x, got %x", common.Address{1}, outAddrStruct.A[0])
+	}
+
+	if len(outAddrStruct.B) != 2 {
+		t.Fatal("expected 1 item, got", len(outAddrStruct.B))
+	}
+
+	if outAddrStruct.B[0] != (common.Address{2}) {
+		t.Errorf("expected %x, got %x", common.Address{2}, outAddrStruct.B[0])
+	}
+	if outAddrStruct.B[1] != (common.Address{3}) {
+		t.Errorf("expected %x, got %x", common.Address{3}, outAddrStruct.B[1])
+	}
+
+	// marshal invalid address slice
+	buff.Reset()
+	buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000100"))
+
+	err = abi.Unpack(&outAddr, "addressSliceSingle", buff.Bytes())
+	if err == nil {
+		t.Fatal("expected error:", err)
+	}
+}
+
+func TestOOMMaliciousInput(t *testing.T) {
+	oomTests := []unpackTest{
+		{
+			def: `[{"type": "uint8[]"}]`,
+			enc: "0000000000000000000000000000000000000000000000000000000000000020" + // offset
+				"0000000000000000000000000000000000000000000000000000000000000003" + // num elems
+				"0000000000000000000000000000000000000000000000000000000000000001" + // elem 1
+				"0000000000000000000000000000000000000000000000000000000000000002", // elem 2
+		},
+		{ // Length larger than 64 bits
+			def: `[{"type": "uint8[]"}]`,
+			enc: "0000000000000000000000000000000000000000000000000000000000000020" + // offset
+				"00ffffffffffffffffffffffffffffffffffffffffffffff0000000000000002" + // num elems
+				"0000000000000000000000000000000000000000000000000000000000000001" + // elem 1
+				"0000000000000000000000000000000000000000000000000000000000000002", // elem 2
+		},
+		{ // Offset very large (over 64 bits)
+			def: `[{"type": "uint8[]"}]`,
+			enc: "00ffffffffffffffffffffffffffffffffffffffffffffff0000000000000020" + // offset
+				"0000000000000000000000000000000000000000000000000000000000000002" + // num elems
+				"0000000000000000000000000000000000000000000000000000000000000001" + // elem 1
+				"0000000000000000000000000000000000000000000000000000000000000002", // elem 2
+		},
+		{ // Offset very large (below 64 bits)
+			def: `[{"type": "uint8[]"}]`,
+			enc: "0000000000000000000000000000000000000000000000007ffffffffff00020" + // offset
+				"0000000000000000000000000000000000000000000000000000000000000002" + // num elems
+				"0000000000000000000000000000000000000000000000000000000000000001" + // elem 1
+				"0000000000000000000000000000000000000000000000000000000000000002", // elem 2
+		},
+		{ // Offset negative (as 64 bit)
+			def: `[{"type": "uint8[]"}]`,
+			enc: "000000000000000000000000000000000000000000000000f000000000000020" + // offset
+				"0000000000000000000000000000000000000000000000000000000000000002" + // num elems
+				"0000000000000000000000000000000000000000000000000000000000000001" + // elem 1
+				"0000000000000000000000000000000000000000000000000000000000000002", // elem 2
+		},
+
+		{ // Negative length
+			def: `[{"type": "uint8[]"}]`,
+			enc: "0000000000000000000000000000000000000000000000000000000000000020" + // offset
+				"000000000000000000000000000000000000000000000000f000000000000002" + // num elems
+				"0000000000000000000000000000000000000000000000000000000000000001" + // elem 1
+				"0000000000000000000000000000000000000000000000000000000000000002", // elem 2
+		},
+		{ // Very large length
+			def: `[{"type": "uint8[]"}]`,
+			enc: "0000000000000000000000000000000000000000000000000000000000000020" + // offset
+				"0000000000000000000000000000000000000000000000007fffffffff000002" + // num elems
+				"0000000000000000000000000000000000000000000000000000000000000001" + // elem 1
+				"0000000000000000000000000000000000000000000000000000000000000002", // elem 2
+		},
+	}
+	for i, test := range oomTests {
+		def := fmt.Sprintf(`[{ "name" : "method", "outputs": %s}]`, test.def)
+		abi, err := JSON(strings.NewReader(def))
+		if err != nil {
+			t.Fatalf("invalid ABI definition %s: %v", def, err)
+		}
+		encb, err := hex.DecodeString(test.enc)
+		if err != nil {
+			t.Fatalf("invalid hex: %s" + test.enc)
+		}
+		_, err = abi.Methods["method"].Outputs.UnpackValues(encb)
+		if err == nil {
+			t.Fatalf("Expected error on malicious input, test %d", i)
+		}
+	}
+}
--- a/accounts/account_manager.go
+++ b/accounts/account_manager.go
@@ -1,363 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-// Package accounts implements encrypted storage of secp256k1 private keys.
-//
-// Keys are stored as encrypted JSON files according to the Web3 Secret Storage specification.
-// See https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition for more information.
-package accounts
-
-import (
-	"crypto/ecdsa"
-	crand "crypto/rand"
-	"encoding/json"
-	"errors"
-	"fmt"
-	"os"
-	"path/filepath"
-	"runtime"
-	"sync"
-	"time"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/crypto"
-)
-
-var (
-	ErrLocked  = errors.New("account is locked")
-	ErrNoMatch = errors.New("no key for given address or file")
-	ErrDecrypt = errors.New("could not decrypt key with given passphrase")
-)
-
-// Account represents a stored key.
-// When used as an argument, it selects a unique key file to act on.
-type Account struct {
-	Address common.Address // Ethereum account address derived from the key
-
-	// File contains the key file name.
-	// When Acccount is used as an argument to select a key, File can be left blank to
-	// select just by address or set to the basename or absolute path of a file in the key
-	// directory. Accounts returned by Manager will always contain an absolute path.
-	File string
-}
-
-func (acc *Account) MarshalJSON() ([]byte, error) {
-	return []byte(`"` + acc.Address.Hex() + `"`), nil
-}
-
-func (acc *Account) UnmarshalJSON(raw []byte) error {
-	return json.Unmarshal(raw, &acc.Address)
-}
-
-// Manager manages a key storage directory on disk.
-type Manager struct {
-	cache    *addrCache
-	keyStore keyStore
-	mu       sync.RWMutex
-	unlocked map[common.Address]*unlocked
-}
-
-type unlocked struct {
-	*Key
-	abort chan struct{}
-}
-
-// NewManager creates a manager for the given directory.
-func NewManager(keydir string, scryptN, scryptP int) *Manager {
-	keydir, _ = filepath.Abs(keydir)
-	am := &Manager{keyStore: &keyStorePassphrase{keydir, scryptN, scryptP}}
-	am.init(keydir)
-	return am
-}
-
-// NewPlaintextManager creates a manager for the given directory.
-// Deprecated: Use NewManager.
-func NewPlaintextManager(keydir string) *Manager {
-	keydir, _ = filepath.Abs(keydir)
-	am := &Manager{keyStore: &keyStorePlain{keydir}}
-	am.init(keydir)
-	return am
-}
-
-func (am *Manager) init(keydir string) {
-	am.unlocked = make(map[common.Address]*unlocked)
-	am.cache = newAddrCache(keydir)
-	// TODO: In order for this finalizer to work, there must be no references
-	// to am. addrCache doesn't keep a reference but unlocked keys do,
-	// so the finalizer will not trigger until all timed unlocks have expired.
-	runtime.SetFinalizer(am, func(m *Manager) {
-		m.cache.close()
-	})
-}
-
-// HasAddress reports whether a key with the given address is present.
-func (am *Manager) HasAddress(addr common.Address) bool {
-	return am.cache.hasAddress(addr)
-}
-
-// Accounts returns all key files present in the directory.
-func (am *Manager) Accounts() []Account {
-	return am.cache.accounts()
-}
-
-// DeleteAccount deletes the key matched by account if the passphrase is correct.
-// If a contains no filename, the address must match a unique key.
-func (am *Manager) DeleteAccount(a Account, passphrase string) error {
-	// Decrypting the key isn't really necessary, but we do
-	// it anyway to check the password and zero out the key
-	// immediately afterwards.
-	a, key, err := am.getDecryptedKey(a, passphrase)
-	if key != nil {
-		zeroKey(key.PrivateKey)
-	}
-	if err != nil {
-		return err
-	}
-	// The order is crucial here. The key is dropped from the
-	// cache after the file is gone so that a reload happening in
-	// between won't insert it into the cache again.
-	err = os.Remove(a.File)
-	if err == nil {
-		am.cache.delete(a)
-	}
-	return err
-}
-
-// Sign calculates a ECDSA signature for the given hash.
-// Note, Ethereum signatures have a particular format as described in the
-// yellow paper. Use the SignEthereum function to calculate a signature
-// in Ethereum format.
-func (am *Manager) Sign(addr common.Address, hash []byte) ([]byte, error) {
-	am.mu.RLock()
-	defer am.mu.RUnlock()
-	unlockedKey, found := am.unlocked[addr]
-	if !found {
-		return nil, ErrLocked
-	}
-	return crypto.Sign(hash, unlockedKey.PrivateKey)
-}
-
-// SignEthereum calculates a ECDSA signature for the given hash.
-// The signature has the format as described in the Ethereum yellow paper.
-func (am *Manager) SignEthereum(addr common.Address, hash []byte) ([]byte, error) {
-	am.mu.RLock()
-	defer am.mu.RUnlock()
-	unlockedKey, found := am.unlocked[addr]
-	if !found {
-		return nil, ErrLocked
-	}
-	return crypto.SignEthereum(hash, unlockedKey.PrivateKey)
-}
-
-// SignWithPassphrase signs hash if the private key matching the given
-// address can be decrypted with the given passphrase.
-func (am *Manager) SignWithPassphrase(addr common.Address, passphrase string, hash []byte) (signature []byte, err error) {
-	_, key, err := am.getDecryptedKey(Account{Address: addr}, passphrase)
-	if err != nil {
-		return nil, err
-	}
-
-	defer zeroKey(key.PrivateKey)
-	return crypto.SignEthereum(hash, key.PrivateKey)
-}
-
-// Unlock unlocks the given account indefinitely.
-func (am *Manager) Unlock(a Account, passphrase string) error {
-	return am.TimedUnlock(a, passphrase, 0)
-}
-
-// Lock removes the private key with the given address from memory.
-func (am *Manager) Lock(addr common.Address) error {
-	am.mu.Lock()
-	if unl, found := am.unlocked[addr]; found {
-		am.mu.Unlock()
-		am.expire(addr, unl, time.Duration(0)*time.Nanosecond)
-	} else {
-		am.mu.Unlock()
-	}
-	return nil
-}
-
-// TimedUnlock unlocks the given account with the passphrase. The account
-// stays unlocked for the duration of timeout. A timeout of 0 unlocks the account
-// until the program exits. The account must match a unique key file.
-//
-// If the account address is already unlocked for a duration, TimedUnlock extends or
-// shortens the active unlock timeout. If the address was previously unlocked
-// indefinitely the timeout is not altered.
-func (am *Manager) TimedUnlock(a Account, passphrase string, timeout time.Duration) error {
-	a, key, err := am.getDecryptedKey(a, passphrase)
-	if err != nil {
-		return err
-	}
-
-	am.mu.Lock()
-	defer am.mu.Unlock()
-	u, found := am.unlocked[a.Address]
-	if found {
-		if u.abort == nil {
-			// The address was unlocked indefinitely, so unlocking
-			// it with a timeout would be confusing.
-			zeroKey(key.PrivateKey)
-			return nil
-		} else {
-			// Terminate the expire goroutine and replace it below.
-			close(u.abort)
-		}
-	}
-	if timeout > 0 {
-		u = &unlocked{Key: key, abort: make(chan struct{})}
-		go am.expire(a.Address, u, timeout)
-	} else {
-		u = &unlocked{Key: key}
-	}
-	am.unlocked[a.Address] = u
-	return nil
-}
-
-// Find resolves the given account into a unique entry in the keystore.
-func (am *Manager) Find(a Account) (Account, error) {
-	am.cache.maybeReload()
-	am.cache.mu.Lock()
-	a, err := am.cache.find(a)
-	am.cache.mu.Unlock()
-	return a, err
-}
-
-func (am *Manager) getDecryptedKey(a Account, auth string) (Account, *Key, error) {
-	a, err := am.Find(a)
-	if err != nil {
-		return a, nil, err
-	}
-	key, err := am.keyStore.GetKey(a.Address, a.File, auth)
-	return a, key, err
-}
-
-func (am *Manager) expire(addr common.Address, u *unlocked, timeout time.Duration) {
-	t := time.NewTimer(timeout)
-	defer t.Stop()
-	select {
-	case <-u.abort:
-		// just quit
-	case <-t.C:
-		am.mu.Lock()
-		// only drop if it's still the same key instance that dropLater
-		// was launched with. we can check that using pointer equality
-		// because the map stores a new pointer every time the key is
-		// unlocked.
-		if am.unlocked[addr] == u {
-			zeroKey(u.PrivateKey)
-			delete(am.unlocked, addr)
-		}
-		am.mu.Unlock()
-	}
-}
-
-// NewAccount generates a new key and stores it into the key directory,
-// encrypting it with the passphrase.
-func (am *Manager) NewAccount(passphrase string) (Account, error) {
-	_, account, err := storeNewKey(am.keyStore, crand.Reader, passphrase)
-	if err != nil {
-		return Account{}, err
-	}
-	// Add the account to the cache immediately rather
-	// than waiting for file system notifications to pick it up.
-	am.cache.add(account)
-	return account, nil
-}
-
-// AccountByIndex returns the ith account.
-func (am *Manager) AccountByIndex(i int) (Account, error) {
-	accounts := am.Accounts()
-	if i < 0 || i >= len(accounts) {
-		return Account{}, fmt.Errorf("account index %d out of range [0, %d]", i, len(accounts)-1)
-	}
-	return accounts[i], nil
-}
-
-// Export exports as a JSON key, encrypted with newPassphrase.
-func (am *Manager) Export(a Account, passphrase, newPassphrase string) (keyJSON []byte, err error) {
-	_, key, err := am.getDecryptedKey(a, passphrase)
-	if err != nil {
-		return nil, err
-	}
-	var N, P int
-	if store, ok := am.keyStore.(*keyStorePassphrase); ok {
-		N, P = store.scryptN, store.scryptP
-	} else {
-		N, P = StandardScryptN, StandardScryptP
-	}
-	return EncryptKey(key, newPassphrase, N, P)
-}
-
-// Import stores the given encrypted JSON key into the key directory.
-func (am *Manager) Import(keyJSON []byte, passphrase, newPassphrase string) (Account, error) {
-	key, err := DecryptKey(keyJSON, passphrase)
-	if key != nil && key.PrivateKey != nil {
-		defer zeroKey(key.PrivateKey)
-	}
-	if err != nil {
-		return Account{}, err
-	}
-	return am.importKey(key, newPassphrase)
-}
-
-// ImportECDSA stores the given key into the key directory, encrypting it with the passphrase.
-func (am *Manager) ImportECDSA(priv *ecdsa.PrivateKey, passphrase string) (Account, error) {
-	key := newKeyFromECDSA(priv)
-	if am.cache.hasAddress(key.Address) {
-		return Account{}, fmt.Errorf("account already exists")
-	}
-
-	return am.importKey(key, passphrase)
-}
-
-func (am *Manager) importKey(key *Key, passphrase string) (Account, error) {
-	a := Account{Address: key.Address, File: am.keyStore.JoinPath(keyFileName(key.Address))}
-	if err := am.keyStore.StoreKey(a.File, key, passphrase); err != nil {
-		return Account{}, err
-	}
-	am.cache.add(a)
-	return a, nil
-}
-
-// Update changes the passphrase of an existing account.
-func (am *Manager) Update(a Account, passphrase, newPassphrase string) error {
-	a, key, err := am.getDecryptedKey(a, passphrase)
-	if err != nil {
-		return err
-	}
-	return am.keyStore.StoreKey(a.File, key, newPassphrase)
-}
-
-// ImportPreSaleKey decrypts the given Ethereum presale wallet and stores
-// a key file in the key directory. The key file is encrypted with the same passphrase.
-func (am *Manager) ImportPreSaleKey(keyJSON []byte, passphrase string) (Account, error) {
-	a, _, err := importPreSaleKey(am.keyStore, keyJSON, passphrase)
-	if err != nil {
-		return a, err
-	}
-	am.cache.add(a)
-	return a, nil
-}
-
-// zeroKey zeroes a private key in memory.
-func zeroKey(k *ecdsa.PrivateKey) {
-	b := k.D.Bits()
-	for i := range b {
-		b[i] = 0
-	}
-}
--- a/accounts/accounts.go
+++ b/accounts/accounts.go
@@ -0,0 +1,173 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// Package accounts implements high level Ethereum account management.
+package accounts
+
+import (
+	"math/big"
+
+	ethereum "github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/event"
+)
+
+// Account represents an Ethereum account located at a specific location defined
+// by the optional URL field.
+type Account struct {
+	Address common.Address `json:"address"` // Ethereum account address derived from the key
+	URL     URL            `json:"url"`     // Optional resource locator within a backend
+}
+
+// Wallet represents a software or hardware wallet that might contain one or more
+// accounts (derived from the same seed).
+type Wallet interface {
+	// URL retrieves the canonical path under which this wallet is reachable. It is
+	// user by upper layers to define a sorting order over all wallets from multiple
+	// backends.
+	URL() URL
+
+	// Status returns a textual status to aid the user in the current state of the
+	// wallet. It also returns an error indicating any failure the wallet might have
+	// encountered.
+	Status() (string, error)
+
+	// Open initializes access to a wallet instance. It is not meant to unlock or
+	// decrypt account keys, rather simply to establish a connection to hardware
+	// wallets and/or to access derivation seeds.
+	//
+	// The passphrase parameter may or may not be used by the implementation of a
+	// particular wallet instance. The reason there is no passwordless open method
+	// is to strive towards a uniform wallet handling, oblivious to the different
+	// backend providers.
+	//
+	// Please note, if you open a wallet, you must close it to release any allocated
+	// resources (especially important when working with hardware wallets).
+	Open(passphrase string) error
+
+	// Close releases any resources held by an open wallet instance.
+	Close() error
+
+	// Accounts retrieves the list of signing accounts the wallet is currently aware
+	// of. For hierarchical deterministic wallets, the list will not be exhaustive,
+	// rather only contain the accounts explicitly pinned during account derivation.
+	Accounts() []Account
+
+	// Contains returns whether an account is part of this particular wallet or not.
+	Contains(account Account) bool
+
+	// Derive attempts to explicitly derive a hierarchical deterministic account at
+	// the specified derivation path. If requested, the derived account will be added
+	// to the wallet's tracked account list.
+	Derive(path DerivationPath, pin bool) (Account, error)
+
+	// SelfDerive sets a base account derivation path from which the wallet attempts
+	// to discover non zero accounts and automatically add them to list of tracked
+	// accounts.
+	//
+	// Note, self derivaton will increment the last component of the specified path
+	// opposed to decending into a child path to allow discovering accounts starting
+	// from non zero components.
+	//
+	// You can disable automatic account discovery by calling SelfDerive with a nil
+	// chain state reader.
+	SelfDerive(base DerivationPath, chain ethereum.ChainStateReader)
+
+	// SignHash requests the wallet to sign the given hash.
+	//
+	// It looks up the account specified either solely via its address contained within,
+	// or optionally with the aid of any location metadata from the embedded URL field.
+	//
+	// If the wallet requires additional authentication to sign the request (e.g.
+	// a password to decrypt the account, or a PIN code o verify the transaction),
+	// an AuthNeededError instance will be returned, containing infos for the user
+	// about which fields or actions are needed. The user may retry by providing
+	// the needed details via SignHashWithPassphrase, or by other means (e.g. unlock
+	// the account in a keystore).
+	SignHash(account Account, hash []byte) ([]byte, error)
+
+	// SignTx requests the wallet to sign the given transaction.
+	//
+	// It looks up the account specified either solely via its address contained within,
+	// or optionally with the aid of any location metadata from the embedded URL field.
+	//
+	// If the wallet requires additional authentication to sign the request (e.g.
+	// a password to decrypt the account, or a PIN code o verify the transaction),
+	// an AuthNeededError instance will be returned, containing infos for the user
+	// about which fields or actions are needed. The user may retry by providing
+	// the needed details via SignTxWithPassphrase, or by other means (e.g. unlock
+	// the account in a keystore).
+	SignTx(account Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error)
+
+	// SignHashWithPassphrase requests the wallet to sign the given hash with the
+	// given passphrase as extra authentication information.
+	//
+	// It looks up the account specified either solely via its address contained within,
+	// or optionally with the aid of any location metadata from the embedded URL field.
+	SignHashWithPassphrase(account Account, passphrase string, hash []byte) ([]byte, error)
+
+	// SignTxWithPassphrase requests the wallet to sign the given transaction, with the
+	// given passphrase as extra authentication information.
+	//
+	// It looks up the account specified either solely via its address contained within,
+	// or optionally with the aid of any location metadata from the embedded URL field.
+	SignTxWithPassphrase(account Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error)
+}
+
+// Backend is a "wallet provider" that may contain a batch of accounts they can
+// sign transactions with and upon request, do so.
+type Backend interface {
+	// Wallets retrieves the list of wallets the backend is currently aware of.
+	//
+	// The returned wallets are not opened by default. For software HD wallets this
+	// means that no base seeds are decrypted, and for hardware wallets that no actual
+	// connection is established.
+	//
+	// The resulting wallet list will be sorted alphabetically based on its internal
+	// URL assigned by the backend. Since wallets (especially hardware) may come and
+	// go, the same wallet might appear at a different positions in the list during
+	// subsequent retrievals.
+	Wallets() []Wallet
+
+	// Subscribe creates an async subscription to receive notifications when the
+	// backend detects the arrival or departure of a wallet.
+	Subscribe(sink chan<- WalletEvent) event.Subscription
+}
+
+// WalletEventType represents the different event types that can be fired by
+// the wallet subscription subsystem.
+type WalletEventType int
+
+const (
+	// WalletArrived is fired when a new wallet is detected either via USB or via
+	// a filesystem event in the keystore.
+	WalletArrived WalletEventType = iota
+
+	// WalletOpened is fired when a wallet is successfully opened with the purpose
+	// of starting any background processes such as automatic key derivation.
+	WalletOpened
+
+	// WalletDropped
+	WalletDropped
+)
+
+// WalletEvent is an event fired by an account backend when a wallet arrival or
+// departure is detected.
+type WalletEvent struct {
+	Wallet Wallet          // Wallet instance arrived or departed
+	Kind   WalletEventType // Event type that happened in the system
+}
--- a/accounts/accounts_test.go
+++ b/accounts/accounts_test.go
@@ -1,218 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package accounts
-
-import (
-	"io/ioutil"
-	"os"
-	"runtime"
-	"strings"
-	"testing"
-	"time"
-
-	"github.com/ethereum/go-ethereum/common"
-)
-
-var testSigData = make([]byte, 32)
-
-func TestManager(t *testing.T) {
-	dir, am := tmpManager(t, true)
-	defer os.RemoveAll(dir)
-
-	a, err := am.NewAccount("foo")
-	if err != nil {
-		t.Fatal(err)
-	}
-	if !strings.HasPrefix(a.File, dir) {
-		t.Errorf("account file %s doesn't have dir prefix", a.File)
-	}
-	stat, err := os.Stat(a.File)
-	if err != nil {
-		t.Fatalf("account file %s doesn't exist (%v)", a.File, err)
-	}
-	if runtime.GOOS != "windows" && stat.Mode() != 0600 {
-		t.Fatalf("account file has wrong mode: got %o, want %o", stat.Mode(), 0600)
-	}
-	if !am.HasAddress(a.Address) {
-		t.Errorf("HasAccount(%x) should've returned true", a.Address)
-	}
-	if err := am.Update(a, "foo", "bar"); err != nil {
-		t.Errorf("Update error: %v", err)
-	}
-	if err := am.DeleteAccount(a, "bar"); err != nil {
-		t.Errorf("DeleteAccount error: %v", err)
-	}
-	if common.FileExist(a.File) {
-		t.Errorf("account file %s should be gone after DeleteAccount", a.File)
-	}
-	if am.HasAddress(a.Address) {
-		t.Errorf("HasAccount(%x) should've returned true after DeleteAccount", a.Address)
-	}
-}
-
-func TestSign(t *testing.T) {
-	dir, am := tmpManager(t, true)
-	defer os.RemoveAll(dir)
-
-	pass := "" // not used but required by API
-	a1, err := am.NewAccount(pass)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if err := am.Unlock(a1, ""); err != nil {
-		t.Fatal(err)
-	}
-	if _, err := am.Sign(a1.Address, testSigData); err != nil {
-		t.Fatal(err)
-	}
-}
-
-func TestSignWithPassphrase(t *testing.T) {
-	dir, am := tmpManager(t, true)
-	defer os.RemoveAll(dir)
-
-	pass := "passwd"
-	acc, err := am.NewAccount(pass)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if _, unlocked := am.unlocked[acc.Address]; unlocked {
-		t.Fatal("expected account to be locked")
-	}
-
-	_, err = am.SignWithPassphrase(acc.Address, pass, testSigData)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if _, unlocked := am.unlocked[acc.Address]; unlocked {
-		t.Fatal("expected account to be locked")
-	}
-
-	if _, err = am.SignWithPassphrase(acc.Address, "invalid passwd", testSigData); err == nil {
-		t.Fatal("expected SignHash to fail with invalid password")
-	}
-}
-
-func TestTimedUnlock(t *testing.T) {
-	dir, am := tmpManager(t, true)
-	defer os.RemoveAll(dir)
-
-	pass := "foo"
-	a1, err := am.NewAccount(pass)
-
-	// Signing without passphrase fails because account is locked
-	_, err = am.Sign(a1.Address, testSigData)
-	if err != ErrLocked {
-		t.Fatal("Signing should've failed with ErrLocked before unlocking, got ", err)
-	}
-
-	// Signing with passphrase works
-	if err = am.TimedUnlock(a1, pass, 100*time.Millisecond); err != nil {
-		t.Fatal(err)
-	}
-
-	// Signing without passphrase works because account is temp unlocked
-	_, err = am.Sign(a1.Address, testSigData)
-	if err != nil {
-		t.Fatal("Signing shouldn't return an error after unlocking, got ", err)
-	}
-
-	// Signing fails again after automatic locking
-	time.Sleep(250 * time.Millisecond)
-	_, err = am.Sign(a1.Address, testSigData)
-	if err != ErrLocked {
-		t.Fatal("Signing should've failed with ErrLocked timeout expired, got ", err)
-	}
-}
-
-func TestOverrideUnlock(t *testing.T) {
-	dir, am := tmpManager(t, false)
-	defer os.RemoveAll(dir)
-
-	pass := "foo"
-	a1, err := am.NewAccount(pass)
-
-	// Unlock indefinitely.
-	if err = am.TimedUnlock(a1, pass, 5*time.Minute); err != nil {
-		t.Fatal(err)
-	}
-
-	// Signing without passphrase works because account is temp unlocked
-	_, err = am.Sign(a1.Address, testSigData)
-	if err != nil {
-		t.Fatal("Signing shouldn't return an error after unlocking, got ", err)
-	}
-
-	// reset unlock to a shorter period, invalidates the previous unlock
-	if err = am.TimedUnlock(a1, pass, 100*time.Millisecond); err != nil {
-		t.Fatal(err)
-	}
-
-	// Signing without passphrase still works because account is temp unlocked
-	_, err = am.Sign(a1.Address, testSigData)
-	if err != nil {
-		t.Fatal("Signing shouldn't return an error after unlocking, got ", err)
-	}
-
-	// Signing fails again after automatic locking
-	time.Sleep(250 * time.Millisecond)
-	_, err = am.Sign(a1.Address, testSigData)
-	if err != ErrLocked {
-		t.Fatal("Signing should've failed with ErrLocked timeout expired, got ", err)
-	}
-}
-
-// This test should fail under -race if signing races the expiration goroutine.
-func TestSignRace(t *testing.T) {
-	dir, am := tmpManager(t, false)
-	defer os.RemoveAll(dir)
-
-	// Create a test account.
-	a1, err := am.NewAccount("")
-	if err != nil {
-		t.Fatal("could not create the test account", err)
-	}
-
-	if err := am.TimedUnlock(a1, "", 15*time.Millisecond); err != nil {
-		t.Fatal("could not unlock the test account", err)
-	}
-	end := time.Now().Add(500 * time.Millisecond)
-	for time.Now().Before(end) {
-		if _, err := am.Sign(a1.Address, testSigData); err == ErrLocked {
-			return
-		} else if err != nil {
-			t.Errorf("Sign error: %v", err)
-			return
-		}
-		time.Sleep(1 * time.Millisecond)
-	}
-	t.Errorf("Account did not lock within the timeout")
-}
-
-func tmpManager(t *testing.T, encrypted bool) (string, *Manager) {
-	d, err := ioutil.TempDir("", "eth-keystore-test")
-	if err != nil {
-		t.Fatal(err)
-	}
-	new := NewPlaintextManager
-	if encrypted {
-		new = func(kd string) *Manager { return NewManager(kd, veryLightScryptN, veryLightScryptP) }
-	}
-	return d, new(d)
-}
--- a/accounts/addrcache.go
+++ b/accounts/addrcache.go
@@ -1,269 +0,0 @@
-// Copyright 2016 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package accounts
-
-import (
-	"bufio"
-	"encoding/json"
-	"fmt"
-	"io/ioutil"
-	"os"
-	"path/filepath"
-	"sort"
-	"strings"
-	"sync"
-	"time"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/logger"
-	"github.com/ethereum/go-ethereum/logger/glog"
-)
-
-// Minimum amount of time between cache reloads. This limit applies if the platform does
-// not support change notifications. It also applies if the keystore directory does not
-// exist yet, the code will attempt to create a watcher at most this often.
-const minReloadInterval = 2 * time.Second
-
-type accountsByFile []Account
-
-func (s accountsByFile) Len() int           { return len(s) }
-func (s accountsByFile) Less(i, j int) bool { return s[i].File < s[j].File }
-func (s accountsByFile) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
-
-// AmbiguousAddrError is returned when attempting to unlock
-// an address for which more than one file exists.
-type AmbiguousAddrError struct {
-	Addr    common.Address
-	Matches []Account
-}
-
-func (err *AmbiguousAddrError) Error() string {
-	files := ""
-	for i, a := range err.Matches {
-		files += a.File
-		if i < len(err.Matches)-1 {
-			files += ", "
-		}
-	}
-	return fmt.Sprintf("multiple keys match address (%s)", files)
-}
-
-// addrCache is a live index of all accounts in the keystore.
-type addrCache struct {
-	keydir   string
-	watcher  *watcher
-	mu       sync.Mutex
-	all      accountsByFile
-	byAddr   map[common.Address][]Account
-	throttle *time.Timer
-}
-
-func newAddrCache(keydir string) *addrCache {
-	ac := &addrCache{
-		keydir: keydir,
-		byAddr: make(map[common.Address][]Account),
-	}
-	ac.watcher = newWatcher(ac)
-	return ac
-}
-
-func (ac *addrCache) accounts() []Account {
-	ac.maybeReload()
-	ac.mu.Lock()
-	defer ac.mu.Unlock()
-	cpy := make([]Account, len(ac.all))
-	copy(cpy, ac.all)
-	return cpy
-}
-
-func (ac *addrCache) hasAddress(addr common.Address) bool {
-	ac.maybeReload()
-	ac.mu.Lock()
-	defer ac.mu.Unlock()
-	return len(ac.byAddr[addr]) > 0
-}
-
-func (ac *addrCache) add(newAccount Account) {
-	ac.mu.Lock()
-	defer ac.mu.Unlock()
-
-	i := sort.Search(len(ac.all), func(i int) bool { return ac.all[i].File >= newAccount.File })
-	if i < len(ac.all) && ac.all[i] == newAccount {
-		return
-	}
-	// newAccount is not in the cache.
-	ac.all = append(ac.all, Account{})
-	copy(ac.all[i+1:], ac.all[i:])
-	ac.all[i] = newAccount
-	ac.byAddr[newAccount.Address] = append(ac.byAddr[newAccount.Address], newAccount)
-}
-
-// note: removed needs to be unique here (i.e. both File and Address must be set).
-func (ac *addrCache) delete(removed Account) {
-	ac.mu.Lock()
-	defer ac.mu.Unlock()
-	ac.all = removeAccount(ac.all, removed)
-	if ba := removeAccount(ac.byAddr[removed.Address], removed); len(ba) == 0 {
-		delete(ac.byAddr, removed.Address)
-	} else {
-		ac.byAddr[removed.Address] = ba
-	}
-}
-
-func removeAccount(slice []Account, elem Account) []Account {
-	for i := range slice {
-		if slice[i] == elem {
-			return append(slice[:i], slice[i+1:]...)
-		}
-	}
-	return slice
-}
-
-// find returns the cached account for address if there is a unique match.
-// The exact matching rules are explained by the documentation of Account.
-// Callers must hold ac.mu.
-func (ac *addrCache) find(a Account) (Account, error) {
-	// Limit search to address candidates if possible.
-	matches := ac.all
-	if (a.Address != common.Address{}) {
-		matches = ac.byAddr[a.Address]
-	}
-	if a.File != "" {
-		// If only the basename is specified, complete the path.
-		if !strings.ContainsRune(a.File, filepath.Separator) {
-			a.File = filepath.Join(ac.keydir, a.File)
-		}
-		for i := range matches {
-			if matches[i].File == a.File {
-				return matches[i], nil
-			}
-		}
-		if (a.Address == common.Address{}) {
-			return Account{}, ErrNoMatch
-		}
-	}
-	switch len(matches) {
-	case 1:
-		return matches[0], nil
-	case 0:
-		return Account{}, ErrNoMatch
-	default:
-		err := &AmbiguousAddrError{Addr: a.Address, Matches: make([]Account, len(matches))}
-		copy(err.Matches, matches)
-		return Account{}, err
-	}
-}
-
-func (ac *addrCache) maybeReload() {
-	ac.mu.Lock()
-	defer ac.mu.Unlock()
-	if ac.watcher.running {
-		return // A watcher is running and will keep the cache up-to-date.
-	}
-	if ac.throttle == nil {
-		ac.throttle = time.NewTimer(0)
-	} else {
-		select {
-		case <-ac.throttle.C:
-		default:
-			return // The cache was reloaded recently.
-		}
-	}
-	ac.watcher.start()
-	ac.reload()
-	ac.throttle.Reset(minReloadInterval)
-}
-
-func (ac *addrCache) close() {
-	ac.mu.Lock()
-	ac.watcher.close()
-	if ac.throttle != nil {
-		ac.throttle.Stop()
-	}
-	ac.mu.Unlock()
-}
-
-// reload caches addresses of existing accounts.
-// Callers must hold ac.mu.
-func (ac *addrCache) reload() {
-	accounts, err := ac.scan()
-	if err != nil && glog.V(logger.Debug) {
-		glog.Errorf("can't load keys: %v", err)
-	}
-	ac.all = accounts
-	sort.Sort(ac.all)
-	for k := range ac.byAddr {
-		delete(ac.byAddr, k)
-	}
-	for _, a := range accounts {
-		ac.byAddr[a.Address] = append(ac.byAddr[a.Address], a)
-	}
-	glog.V(logger.Debug).Infof("reloaded keys, cache has %d accounts", len(ac.all))
-}
-
-func (ac *addrCache) scan() ([]Account, error) {
-	files, err := ioutil.ReadDir(ac.keydir)
-	if err != nil {
-		return nil, err
-	}
-
-	var (
-		buf     = new(bufio.Reader)
-		addrs   []Account
-		keyJSON struct {
-			Address common.Address `json:"address"`
-		}
-	)
-	for _, fi := range files {
-		path := filepath.Join(ac.keydir, fi.Name())
-		if skipKeyFile(fi) {
-			glog.V(logger.Detail).Infof("ignoring file %s", path)
-			continue
-		}
-		fd, err := os.Open(path)
-		if err != nil {
-			glog.V(logger.Detail).Infoln(err)
-			continue
-		}
-		buf.Reset(fd)
-		// Parse the address.
-		keyJSON.Address = common.Address{}
-		err = json.NewDecoder(buf).Decode(&keyJSON)
-		switch {
-		case err != nil:
-			glog.V(logger.Debug).Infof("can't decode key %s: %v", path, err)
-		case (keyJSON.Address == common.Address{}):
-			glog.V(logger.Debug).Infof("can't decode key %s: missing or zero address", path)
-		default:
-			addrs = append(addrs, Account{Address: keyJSON.Address, File: path})
-		}
-		fd.Close()
-	}
-	return addrs, err
-}
-
-func skipKeyFile(fi os.FileInfo) bool {
-	// Skip editor backups and UNIX-style hidden files.
-	if strings.HasSuffix(fi.Name(), "~") || strings.HasPrefix(fi.Name(), ".") {
-		return true
-	}
-	// Skip misc special files, directories (yes, symlinks too).
-	if fi.IsDir() || fi.Mode()&os.ModeType != 0 {
-		return true
-	}
-	return false
-}
--- a/accounts/addrcache_test.go
+++ b/accounts/addrcache_test.go
@@ -1,283 +0,0 @@
-// Copyright 2016 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package accounts
-
-import (
-	"fmt"
-	"math/rand"
-	"os"
-	"path/filepath"
-	"reflect"
-	"sort"
-	"testing"
-	"time"
-
-	"github.com/cespare/cp"
-	"github.com/davecgh/go-spew/spew"
-	"github.com/ethereum/go-ethereum/common"
-)
-
-var (
-	cachetestDir, _   = filepath.Abs(filepath.Join("testdata", "keystore"))
-	cachetestAccounts = []Account{
-		{
-			Address: common.HexToAddress("7ef5a6135f1fd6a02593eedc869c6d41d934aef8"),
-			File:    filepath.Join(cachetestDir, "UTC--2016-03-22T12-57-55.920751759Z--7ef5a6135f1fd6a02593eedc869c6d41d934aef8"),
-		},
-		{
-			Address: common.HexToAddress("f466859ead1932d743d622cb74fc058882e8648a"),
-			File:    filepath.Join(cachetestDir, "aaa"),
-		},
-		{
-			Address: common.HexToAddress("289d485d9771714cce91d3393d764e1311907acc"),
-			File:    filepath.Join(cachetestDir, "zzz"),
-		},
-	}
-)
-
-func TestWatchNewFile(t *testing.T) {
-	t.Parallel()
-
-	dir, am := tmpManager(t, false)
-	defer os.RemoveAll(dir)
-
-	// Ensure the watcher is started before adding any files.
-	am.Accounts()
-	time.Sleep(200 * time.Millisecond)
-
-	// Move in the files.
-	wantAccounts := make([]Account, len(cachetestAccounts))
-	for i := range cachetestAccounts {
-		a := cachetestAccounts[i]
-		a.File = filepath.Join(dir, filepath.Base(a.File))
-		wantAccounts[i] = a
-		if err := cp.CopyFile(a.File, cachetestAccounts[i].File); err != nil {
-			t.Fatal(err)
-		}
-	}
-
-	// am should see the accounts.
-	var list []Account
-	for d := 200 * time.Millisecond; d < 5*time.Second; d *= 2 {
-		list = am.Accounts()
-		if reflect.DeepEqual(list, wantAccounts) {
-			return
-		}
-		time.Sleep(d)
-	}
-	t.Errorf("got %s, want %s", spew.Sdump(list), spew.Sdump(wantAccounts))
-}
-
-func TestWatchNoDir(t *testing.T) {
-	t.Parallel()
-
-	// Create am but not the directory that it watches.
-	rand.Seed(time.Now().UnixNano())
-	dir := filepath.Join(os.TempDir(), fmt.Sprintf("eth-keystore-watch-test-%d-%d", os.Getpid(), rand.Int()))
-	am := NewManager(dir, LightScryptN, LightScryptP)
-
-	list := am.Accounts()
-	if len(list) > 0 {
-		t.Error("initial account list not empty:", list)
-	}
-	time.Sleep(100 * time.Millisecond)
-
-	// Create the directory and copy a key file into it.
-	os.MkdirAll(dir, 0700)
-	defer os.RemoveAll(dir)
-	file := filepath.Join(dir, "aaa")
-	if err := cp.CopyFile(file, cachetestAccounts[0].File); err != nil {
-		t.Fatal(err)
-	}
-
-	// am should see the account.
-	wantAccounts := []Account{cachetestAccounts[0]}
-	wantAccounts[0].File = file
-	for d := 200 * time.Millisecond; d < 8*time.Second; d *= 2 {
-		list = am.Accounts()
-		if reflect.DeepEqual(list, wantAccounts) {
-			return
-		}
-		time.Sleep(d)
-	}
-	t.Errorf("\ngot  %v\nwant %v", list, wantAccounts)
-}
-
-func TestCacheInitialReload(t *testing.T) {
-	cache := newAddrCache(cachetestDir)
-	accounts := cache.accounts()
-	if !reflect.DeepEqual(accounts, cachetestAccounts) {
-		t.Fatalf("got initial accounts: %swant %s", spew.Sdump(accounts), spew.Sdump(cachetestAccounts))
-	}
-}
-
-func TestCacheAddDeleteOrder(t *testing.T) {
-	cache := newAddrCache("testdata/no-such-dir")
-	cache.watcher.running = true // prevent unexpected reloads
-
-	accounts := []Account{
-		{
-			Address: common.HexToAddress("095e7baea6a6c7c4c2dfeb977efac326af552d87"),
-			File:    "-309830980",
-		},
-		{
-			Address: common.HexToAddress("2cac1adea150210703ba75ed097ddfe24e14f213"),
-			File:    "ggg",
-		},
-		{
-			Address: common.HexToAddress("8bda78331c916a08481428e4b07c96d3e916d165"),
-			File:    "zzzzzz-the-very-last-one.keyXXX",
-		},
-		{
-			Address: common.HexToAddress("d49ff4eeb0b2686ed89c0fc0f2b6ea533ddbbd5e"),
-			File:    "SOMETHING.key",
-		},
-		{
-			Address: common.HexToAddress("7ef5a6135f1fd6a02593eedc869c6d41d934aef8"),
-			File:    "UTC--2016-03-22T12-57-55.920751759Z--7ef5a6135f1fd6a02593eedc869c6d41d934aef8",
-		},
-		{
-			Address: common.HexToAddress("f466859ead1932d743d622cb74fc058882e8648a"),
-			File:    "aaa",
-		},
-		{
-			Address: common.HexToAddress("289d485d9771714cce91d3393d764e1311907acc"),
-			File:    "zzz",
-		},
-	}
-	for _, a := range accounts {
-		cache.add(a)
-	}
-	// Add some of them twice to check that they don't get reinserted.
-	cache.add(accounts[0])
-	cache.add(accounts[2])
-
-	// Check that the account list is sorted by filename.
-	wantAccounts := make([]Account, len(accounts))
-	copy(wantAccounts, accounts)
-	sort.Sort(accountsByFile(wantAccounts))
-	list := cache.accounts()
-	if !reflect.DeepEqual(list, wantAccounts) {
-		t.Fatalf("got accounts: %s\nwant %s", spew.Sdump(accounts), spew.Sdump(wantAccounts))
-	}
-	for _, a := range accounts {
-		if !cache.hasAddress(a.Address) {
-			t.Errorf("expected hasAccount(%x) to return true", a.Address)
-		}
-	}
-	if cache.hasAddress(common.HexToAddress("fd9bd350f08ee3c0c19b85a8e16114a11a60aa4e")) {
-		t.Errorf("expected hasAccount(%x) to return false", common.HexToAddress("fd9bd350f08ee3c0c19b85a8e16114a11a60aa4e"))
-	}
-
-	// Delete a few keys from the cache.
-	for i := 0; i < len(accounts); i += 2 {
-		cache.delete(wantAccounts[i])
-	}
-	cache.delete(Account{Address: common.HexToAddress("fd9bd350f08ee3c0c19b85a8e16114a11a60aa4e"), File: "something"})
-
-	// Check content again after deletion.
-	wantAccountsAfterDelete := []Account{
-		wantAccounts[1],
-		wantAccounts[3],
-		wantAccounts[5],
-	}
-	list = cache.accounts()
-	if !reflect.DeepEqual(list, wantAccountsAfterDelete) {
-		t.Fatalf("got accounts after delete: %s\nwant %s", spew.Sdump(list), spew.Sdump(wantAccountsAfterDelete))
-	}
-	for _, a := range wantAccountsAfterDelete {
-		if !cache.hasAddress(a.Address) {
-			t.Errorf("expected hasAccount(%x) to return true", a.Address)
-		}
-	}
-	if cache.hasAddress(wantAccounts[0].Address) {
-		t.Errorf("expected hasAccount(%x) to return false", wantAccounts[0].Address)
-	}
-}
-
-func TestCacheFind(t *testing.T) {
-	dir := filepath.Join("testdata", "dir")
-	cache := newAddrCache(dir)
-	cache.watcher.running = true // prevent unexpected reloads
-
-	accounts := []Account{
-		{
-			Address: common.HexToAddress("095e7baea6a6c7c4c2dfeb977efac326af552d87"),
-			File:    filepath.Join(dir, "a.key"),
-		},
-		{
-			Address: common.HexToAddress("2cac1adea150210703ba75ed097ddfe24e14f213"),
-			File:    filepath.Join(dir, "b.key"),
-		},
-		{
-			Address: common.HexToAddress("d49ff4eeb0b2686ed89c0fc0f2b6ea533ddbbd5e"),
-			File:    filepath.Join(dir, "c.key"),
-		},
-		{
-			Address: common.HexToAddress("d49ff4eeb0b2686ed89c0fc0f2b6ea533ddbbd5e"),
-			File:    filepath.Join(dir, "c2.key"),
-		},
-	}
-	for _, a := range accounts {
-		cache.add(a)
-	}
-
-	nomatchAccount := Account{
-		Address: common.HexToAddress("f466859ead1932d743d622cb74fc058882e8648a"),
-		File:    filepath.Join(dir, "something"),
-	}
-	tests := []struct {
-		Query      Account
-		WantResult Account
-		WantError  error
-	}{
-		// by address
-		{Query: Account{Address: accounts[0].Address}, WantResult: accounts[0]},
-		// by file
-		{Query: Account{File: accounts[0].File}, WantResult: accounts[0]},
-		// by basename
-		{Query: Account{File: filepath.Base(accounts[0].File)}, WantResult: accounts[0]},
-		// by file and address
-		{Query: accounts[0], WantResult: accounts[0]},
-		// ambiguous address, tie resolved by file
-		{Query: accounts[2], WantResult: accounts[2]},
-		// ambiguous address error
-		{
-			Query: Account{Address: accounts[2].Address},
-			WantError: &AmbiguousAddrError{
-				Addr:    accounts[2].Address,
-				Matches: []Account{accounts[2], accounts[3]},
-			},
-		},
-		// no match error
-		{Query: nomatchAccount, WantError: ErrNoMatch},
-		{Query: Account{File: nomatchAccount.File}, WantError: ErrNoMatch},
-		{Query: Account{File: filepath.Base(nomatchAccount.File)}, WantError: ErrNoMatch},
-		{Query: Account{Address: nomatchAccount.Address}, WantError: ErrNoMatch},
-	}
-	for i, test := range tests {
-		a, err := cache.find(test.Query)
-		if !reflect.DeepEqual(err, test.WantError) {
-			t.Errorf("test %d: error mismatch for query %v\ngot %q\nwant %q", i, test.Query, err, test.WantError)
-			continue
-		}
-		if a != test.WantResult {
-			t.Errorf("test %d: result mismatch for query %v\ngot %v\nwant %v", i, test.Query, a, test.WantResult)
-			continue
-		}
-	}
-}
--- a/accounts/errors.go
+++ b/accounts/errors.go
@@ -0,0 +1,68 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package accounts
+
+import (
+	"errors"
+	"fmt"
+)
+
+// ErrUnknownAccount is returned for any requested operation for which no backend
+// provides the specified account.
+var ErrUnknownAccount = errors.New("unknown account")
+
+// ErrUnknownWallet is returned for any requested operation for which no backend
+// provides the specified wallet.
+var ErrUnknownWallet = errors.New("unknown wallet")
+
+// ErrNotSupported is returned when an operation is requested from an account
+// backend that it does not support.
+var ErrNotSupported = errors.New("not supported")
+
+// ErrInvalidPassphrase is returned when a decryption operation receives a bad
+// passphrase.
+var ErrInvalidPassphrase = errors.New("invalid passphrase")
+
+// ErrWalletAlreadyOpen is returned if a wallet is attempted to be opened the
+// second time.
+var ErrWalletAlreadyOpen = errors.New("wallet already open")
+
+// ErrWalletClosed is returned if a wallet is attempted to be opened the
+// secodn time.
+var ErrWalletClosed = errors.New("wallet closed")
+
+// AuthNeededError is returned by backends for signing requests where the user
+// is required to provide further authentication before signing can succeed.
+//
+// This usually means either that a password needs to be supplied, or perhaps a
+// one time PIN code displayed by some hardware device.
+type AuthNeededError struct {
+	Needed string // Extra authentication the user needs to provide
+}
+
+// NewAuthNeededError creates a new authentication error with the extra details
+// about the needed fields set.
+func NewAuthNeededError(needed string) error {
+	return &AuthNeededError{
+		Needed: needed,
+	}
+}
+
+// Error implements the standard error interface.
+func (err *AuthNeededError) Error() string {
+	return fmt.Sprintf("authentication needed: %s", err.Needed)
+}
--- a/accounts/hd.go
+++ b/accounts/hd.go
@@ -0,0 +1,135 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package accounts
+
+import (
+	"errors"
+	"fmt"
+	"math"
+	"math/big"
+	"strings"
+)
+
+// DefaultRootDerivationPath is the root path to which custom derivation endpoints
+// are appended. As such, the first account will be at m/44'/60'/0'/0, the second
+// at m/44'/60'/0'/1, etc.
+var DefaultRootDerivationPath = DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}
+
+// DefaultBaseDerivationPath is the base path from which custom derivation endpoints
+// are incremented. As such, the first account will be at m/44'/60'/0'/0, the second
+// at m/44'/60'/0'/1, etc.
+var DefaultBaseDerivationPath = DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0}
+
+// DefaultLedgerBaseDerivationPath is the base path from which custom derivation endpoints
+// are incremented. As such, the first account will be at m/44'/60'/0'/0, the second
+// at m/44'/60'/0'/1, etc.
+var DefaultLedgerBaseDerivationPath = DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}
+
+// DerivationPath represents the computer friendly version of a hierarchical
+// deterministic wallet account derivaion path.
+//
+// The BIP-32 spec https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki
+// defines derivation paths to be of the form:
+//
+//   m / purpose' / coin_type' / account' / change / address_index
+//
+// The BIP-44 spec https://github.com/bitcoin/bips/blob/master/bip-0044.mediawiki
+// defines that the `purpose` be 44' (or 0x8000002C) for crypto currencies, and
+// SLIP-44 https://github.com/satoshilabs/slips/blob/master/slip-0044.md assigns
+// the `coin_type` 60' (or 0x8000003C) to Ethereum.
+//
+// The root path for Ethereum is m/44'/60'/0'/0 according to the specification
+// from https://github.com/ethereum/EIPs/issues/84, albeit it's not set in stone
+// yet whether accounts should increment the last component or the children of
+// that. We will go with the simpler approach of incrementing the last component.
+type DerivationPath []uint32
+
+// ParseDerivationPath converts a user specified derivation path string to the
+// internal binary representation.
+//
+// Full derivation paths need to start with the `m/` prefix, relative derivation
+// paths (which will get appended to the default root path) must not have prefixes
+// in front of the first element. Whitespace is ignored.
+func ParseDerivationPath(path string) (DerivationPath, error) {
+	var result DerivationPath
+
+	// Handle absolute or relative paths
+	components := strings.Split(path, "/")
+	switch {
+	case len(components) == 0:
+		return nil, errors.New("empty derivation path")
+
+	case strings.TrimSpace(components[0]) == "":
+		return nil, errors.New("ambiguous path: use 'm/' prefix for absolute paths, or no leading '/' for relative ones")
+
+	case strings.TrimSpace(components[0]) == "m":
+		components = components[1:]
+
+	default:
+		result = append(result, DefaultRootDerivationPath...)
+	}
+	// All remaining components are relative, append one by one
+	if len(components) == 0 {
+		return nil, errors.New("empty derivation path") // Empty relative paths
+	}
+	for _, component := range components {
+		// Ignore any user added whitespace
+		component = strings.TrimSpace(component)
+		var value uint32
+
+		// Handle hardened paths
+		if strings.HasSuffix(component, "'") {
+			value = 0x80000000
+			component = strings.TrimSpace(strings.TrimSuffix(component, "'"))
+		}
+		// Handle the non hardened component
+		bigval, ok := new(big.Int).SetString(component, 0)
+		if !ok {
+			return nil, fmt.Errorf("invalid component: %s", component)
+		}
+		max := math.MaxUint32 - value
+		if bigval.Sign() < 0 || bigval.Cmp(big.NewInt(int64(max))) > 0 {
+			if value == 0 {
+				return nil, fmt.Errorf("component %v out of allowed range [0, %d]", bigval, max)
+			}
+			return nil, fmt.Errorf("component %v out of allowed hardened range [0, %d]", bigval, max)
+		}
+		value += uint32(bigval.Uint64())
+
+		// Append and repeat
+		result = append(result, value)
+	}
+	return result, nil
+}
+
+// String implements the stringer interface, converting a binary derivation path
+// to its canonical representation.
+func (path DerivationPath) String() string {
+	result := "m"
+	for _, component := range path {
+		var hardened bool
+		if component >= 0x80000000 {
+			component -= 0x80000000
+			hardened = true
+		}
+		result = fmt.Sprintf("%s/%d", result, component)
+		if hardened {
+			result += "'"
+		}
+	}
+	return result
+}
--- a/accounts/hd_test.go
+++ b/accounts/hd_test.go
@@ -0,0 +1,79 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package accounts
+
+import (
+	"reflect"
+	"testing"
+)
+
+// Tests that HD derivation paths can be correctly parsed into our internal binary
+// representation.
+func TestHDPathParsing(t *testing.T) {
+	tests := []struct {
+		input  string
+		output DerivationPath
+	}{
+		// Plain absolute derivation paths
+		{"m/44'/60'/0'/0", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}},
+		{"m/44'/60'/0'/128", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 128}},
+		{"m/44'/60'/0'/0'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}},
+		{"m/44'/60'/0'/128'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 128}},
+		{"m/2147483692/2147483708/2147483648/0", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}},
+		{"m/2147483692/2147483708/2147483648/2147483648", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}},
+
+		// Plain relative derivation paths
+		{"0", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0}},
+		{"128", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 128}},
+		{"0'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 0}},
+		{"128'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 128}},
+		{"2147483648", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 0}},
+
+		// Hexadecimal absolute derivation paths
+		{"m/0x2C'/0x3c'/0x00'/0x00", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}},
+		{"m/0x2C'/0x3c'/0x00'/0x80", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 128}},
+		{"m/0x2C'/0x3c'/0x00'/0x00'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}},
+		{"m/0x2C'/0x3c'/0x00'/0x80'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 128}},
+		{"m/0x8000002C/0x8000003c/0x80000000/0x00", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}},
+		{"m/0x8000002C/0x8000003c/0x80000000/0x80000000", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}},
+
+		// Hexadecimal relative derivation paths
+		{"0x00", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0}},
+		{"0x80", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 128}},
+		{"0x00'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 0}},
+		{"0x80'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 128}},
+		{"0x80000000", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 0}},
+
+		// Weird inputs just to ensure they work
+		{"	m  /   44			'\n/\n   60	\n\n\t'   /\n0 ' /\t\t	0", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}},
+
+		// Invaid derivation paths
+		{"", nil},              // Empty relative derivation path
+		{"m", nil},             // Empty absolute derivation path
+		{"m/", nil},            // Missing last derivation component
+		{"/44'/60'/0'/0", nil}, // Absolute path without m prefix, might be user error
+		{"m/2147483648'", nil}, // Overflows 32 bit integer
+		{"m/-1'", nil},         // Cannot contain negative number
+	}
+	for i, tt := range tests {
+		if path, err := ParseDerivationPath(tt.input); !reflect.DeepEqual(path, tt.output) {
+			t.Errorf("test %d: parse mismatch: have %v (%v), want %v", i, path, err, tt.output)
+		} else if path == nil && err == nil {
+			t.Errorf("test %d: nil path and error: %v", i, err)
+		}
+	}
+}
--- a/accounts/key_store_passphrase.go
+++ b/accounts/key_store_passphrase.go
@@ -1,305 +0,0 @@
-// Copyright 2014 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-/*
-
-This key store behaves as KeyStorePlain with the difference that
-the private key is encrypted and on disk uses another JSON encoding.
-
-The crypto is documented at https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition
-
-*/
-
-package accounts
-
-import (
-	"bytes"
-	"crypto/aes"
-	"crypto/sha256"
-	"encoding/hex"
-	"encoding/json"
-	"fmt"
-	"io/ioutil"
-	"path/filepath"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/crypto/randentropy"
-	"github.com/pborman/uuid"
-	"golang.org/x/crypto/pbkdf2"
-	"golang.org/x/crypto/scrypt"
-)
-
-const (
-	keyHeaderKDF = "scrypt"
-
-	// StandardScryptN is the N parameter of Scrypt encryption algorithm, using 256MB
-	// memory and taking approximately 1s CPU time on a modern processor.
-	StandardScryptN = 1 << 18
-
-	// StandardScryptP is the P parameter of Scrypt encryption algorithm, using 256MB
-	// memory and taking approximately 1s CPU time on a modern processor.
-	StandardScryptP = 1
-
-	// LightScryptN is the N parameter of Scrypt encryption algorithm, using 4MB
-	// memory and taking approximately 100ms CPU time on a modern processor.
-	LightScryptN = 1 << 12
-
-	// LightScryptP is the P parameter of Scrypt encryption algorithm, using 4MB
-	// memory and taking approximately 100ms CPU time on a modern processor.
-	LightScryptP = 6
-
-	scryptR     = 8
-	scryptDKLen = 32
-)
-
-type keyStorePassphrase struct {
-	keysDirPath string
-	scryptN     int
-	scryptP     int
-}
-
-func (ks keyStorePassphrase) GetKey(addr common.Address, filename, auth string) (*Key, error) {
-	// Load the key from the keystore and decrypt its contents
-	keyjson, err := ioutil.ReadFile(filename)
-	if err != nil {
-		return nil, err
-	}
-	key, err := DecryptKey(keyjson, auth)
-	if err != nil {
-		return nil, err
-	}
-	// Make sure we're really operating on the requested key (no swap attacks)
-	if key.Address != addr {
-		return nil, fmt.Errorf("key content mismatch: have account %x, want %x", key.Address, addr)
-	}
-	return key, nil
-}
-
-func (ks keyStorePassphrase) StoreKey(filename string, key *Key, auth string) error {
-	keyjson, err := EncryptKey(key, auth, ks.scryptN, ks.scryptP)
-	if err != nil {
-		return err
-	}
-	return writeKeyFile(filename, keyjson)
-}
-
-func (ks keyStorePassphrase) JoinPath(filename string) string {
-	if filepath.IsAbs(filename) {
-		return filename
-	} else {
-		return filepath.Join(ks.keysDirPath, filename)
-	}
-}
-
-// EncryptKey encrypts a key using the specified scrypt parameters into a json
-// blob that can be decrypted later on.
-func EncryptKey(key *Key, auth string, scryptN, scryptP int) ([]byte, error) {
-	authArray := []byte(auth)
-	salt := randentropy.GetEntropyCSPRNG(32)
-	derivedKey, err := scrypt.Key(authArray, salt, scryptN, scryptR, scryptP, scryptDKLen)
-	if err != nil {
-		return nil, err
-	}
-	encryptKey := derivedKey[:16]
-	keyBytes0 := crypto.FromECDSA(key.PrivateKey)
-	keyBytes := common.LeftPadBytes(keyBytes0, 32)
-
-	iv := randentropy.GetEntropyCSPRNG(aes.BlockSize) // 16
-	cipherText, err := aesCTRXOR(encryptKey, keyBytes, iv)
-	if err != nil {
-		return nil, err
-	}
-	mac := crypto.Keccak256(derivedKey[16:32], cipherText)
-
-	scryptParamsJSON := make(map[string]interface{}, 5)
-	scryptParamsJSON["n"] = scryptN
-	scryptParamsJSON["r"] = scryptR
-	scryptParamsJSON["p"] = scryptP
-	scryptParamsJSON["dklen"] = scryptDKLen
-	scryptParamsJSON["salt"] = hex.EncodeToString(salt)
-
-	cipherParamsJSON := cipherparamsJSON{
-		IV: hex.EncodeToString(iv),
-	}
-
-	cryptoStruct := cryptoJSON{
-		Cipher:       "aes-128-ctr",
-		CipherText:   hex.EncodeToString(cipherText),
-		CipherParams: cipherParamsJSON,
-		KDF:          "scrypt",
-		KDFParams:    scryptParamsJSON,
-		MAC:          hex.EncodeToString(mac),
-	}
-	encryptedKeyJSONV3 := encryptedKeyJSONV3{
-		hex.EncodeToString(key.Address[:]),
-		cryptoStruct,
-		key.Id.String(),
-		version,
-	}
-	return json.Marshal(encryptedKeyJSONV3)
-}
-
-// DecryptKey decrypts a key from a json blob, returning the private key itself.
-func DecryptKey(keyjson []byte, auth string) (*Key, error) {
-	// Parse the json into a simple map to fetch the key version
-	m := make(map[string]interface{})
-	if err := json.Unmarshal(keyjson, &m); err != nil {
-		return nil, err
-	}
-	// Depending on the version try to parse one way or another
-	var (
-		keyBytes, keyId []byte
-		err             error
-	)
-	if version, ok := m["version"].(string); ok && version == "1" {
-		k := new(encryptedKeyJSONV1)
-		if err := json.Unmarshal(keyjson, k); err != nil {
-			return nil, err
-		}
-		keyBytes, keyId, err = decryptKeyV1(k, auth)
-	} else {
-		k := new(encryptedKeyJSONV3)
-		if err := json.Unmarshal(keyjson, k); err != nil {
-			return nil, err
-		}
-		keyBytes, keyId, err = decryptKeyV3(k, auth)
-	}
-	// Handle any decryption errors and return the key
-	if err != nil {
-		return nil, err
-	}
-	key := crypto.ToECDSA(keyBytes)
-	return &Key{
-		Id:         uuid.UUID(keyId),
-		Address:    crypto.PubkeyToAddress(key.PublicKey),
-		PrivateKey: key,
-	}, nil
-}
-
-func decryptKeyV3(keyProtected *encryptedKeyJSONV3, auth string) (keyBytes []byte, keyId []byte, err error) {
-	if keyProtected.Version != version {
-		return nil, nil, fmt.Errorf("Version not supported: %v", keyProtected.Version)
-	}
-
-	if keyProtected.Crypto.Cipher != "aes-128-ctr" {
-		return nil, nil, fmt.Errorf("Cipher not supported: %v", keyProtected.Crypto.Cipher)
-	}
-
-	keyId = uuid.Parse(keyProtected.Id)
-	mac, err := hex.DecodeString(keyProtected.Crypto.MAC)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	iv, err := hex.DecodeString(keyProtected.Crypto.CipherParams.IV)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	cipherText, err := hex.DecodeString(keyProtected.Crypto.CipherText)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	derivedKey, err := getKDFKey(keyProtected.Crypto, auth)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	calculatedMAC := crypto.Keccak256(derivedKey[16:32], cipherText)
-	if !bytes.Equal(calculatedMAC, mac) {
-		return nil, nil, ErrDecrypt
-	}
-
-	plainText, err := aesCTRXOR(derivedKey[:16], cipherText, iv)
-	if err != nil {
-		return nil, nil, err
-	}
-	return plainText, keyId, err
-}
-
-func decryptKeyV1(keyProtected *encryptedKeyJSONV1, auth string) (keyBytes []byte, keyId []byte, err error) {
-	keyId = uuid.Parse(keyProtected.Id)
-	mac, err := hex.DecodeString(keyProtected.Crypto.MAC)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	iv, err := hex.DecodeString(keyProtected.Crypto.CipherParams.IV)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	cipherText, err := hex.DecodeString(keyProtected.Crypto.CipherText)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	derivedKey, err := getKDFKey(keyProtected.Crypto, auth)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	calculatedMAC := crypto.Keccak256(derivedKey[16:32], cipherText)
-	if !bytes.Equal(calculatedMAC, mac) {
-		return nil, nil, ErrDecrypt
-	}
-
-	plainText, err := aesCBCDecrypt(crypto.Keccak256(derivedKey[:16])[:16], cipherText, iv)
-	if err != nil {
-		return nil, nil, err
-	}
-	return plainText, keyId, err
-}
-
-func getKDFKey(cryptoJSON cryptoJSON, auth string) ([]byte, error) {
-	authArray := []byte(auth)
-	salt, err := hex.DecodeString(cryptoJSON.KDFParams["salt"].(string))
-	if err != nil {
-		return nil, err
-	}
-	dkLen := ensureInt(cryptoJSON.KDFParams["dklen"])
-
-	if cryptoJSON.KDF == "scrypt" {
-		n := ensureInt(cryptoJSON.KDFParams["n"])
-		r := ensureInt(cryptoJSON.KDFParams["r"])
-		p := ensureInt(cryptoJSON.KDFParams["p"])
-		return scrypt.Key(authArray, salt, n, r, p, dkLen)
-
-	} else if cryptoJSON.KDF == "pbkdf2" {
-		c := ensureInt(cryptoJSON.KDFParams["c"])
-		prf := cryptoJSON.KDFParams["prf"].(string)
-		if prf != "hmac-sha256" {
-			return nil, fmt.Errorf("Unsupported PBKDF2 PRF: %s", prf)
-		}
-		key := pbkdf2.Key(authArray, salt, c, dkLen, sha256.New)
-		return key, nil
-	}
-
-	return nil, fmt.Errorf("Unsupported KDF: %s", cryptoJSON.KDF)
-}
-
-// TODO: can we do without this when unmarshalling dynamic JSON?
-// why do integers in KDF params end up as float64 and not int after
-// unmarshal?
-func ensureInt(x interface{}) int {
-	res, ok := x.(int)
-	if !ok {
-		res = int(x.(float64))
-	}
-	return res
-}
--- a/accounts/key_store_passphrase_test.go
+++ b/accounts/key_store_passphrase_test.go
@@ -1,60 +0,0 @@
-// Copyright 2016 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package accounts
-
-import (
-	"io/ioutil"
-	"testing"
-
-	"github.com/ethereum/go-ethereum/common"
-)
-
-const (
-	veryLightScryptN = 2
-	veryLightScryptP = 1
-)
-
-// Tests that a json key file can be decrypted and encrypted in multiple rounds.
-func TestKeyEncryptDecrypt(t *testing.T) {
-	keyjson, err := ioutil.ReadFile("testdata/very-light-scrypt.json")
-	if err != nil {
-		t.Fatal(err)
-	}
-	password := ""
-	address := common.HexToAddress("45dea0fb0bba44f4fcf290bba71fd57d7117cbb8")
-
-	// Do a few rounds of decryption and encryption
-	for i := 0; i < 3; i++ {
-		// Try a bad password first
-		if _, err := DecryptKey(keyjson, password+"bad"); err == nil {
-			t.Errorf("test %d: json key decrypted with bad password", i)
-		}
-		// Decrypt with the correct password
-		key, err := DecryptKey(keyjson, password)
-		if err != nil {
-			t.Errorf("test %d: json key failed to decrypt: %v", i, err)
-		}
-		if key.Address != address {
-			t.Errorf("test %d: key address mismatch: have %x, want %x", i, key.Address, address)
-		}
-		// Recrypt with a new password and start over
-		password += "new data appended"
-		if keyjson, err = EncryptKey(key, password, veryLightScryptN, veryLightScryptP); err != nil {
-			t.Errorf("test %d: failed to recrypt key %v", i, err)
-		}
-	}
-}
--- a/accounts/key_store_plain.go
+++ b/accounts/key_store_plain.go
@@ -1,62 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package accounts
-
-import (
-	"encoding/json"
-	"fmt"
-	"os"
-	"path/filepath"
-
-	"github.com/ethereum/go-ethereum/common"
-)
-
-type keyStorePlain struct {
-	keysDirPath string
-}
-
-func (ks keyStorePlain) GetKey(addr common.Address, filename, auth string) (*Key, error) {
-	fd, err := os.Open(filename)
-	if err != nil {
-		return nil, err
-	}
-	defer fd.Close()
-	key := new(Key)
-	if err := json.NewDecoder(fd).Decode(key); err != nil {
-		return nil, err
-	}
-	if key.Address != addr {
-		return nil, fmt.Errorf("key content mismatch: have address %x, want %x", key.Address, addr)
-	}
-	return key, nil
-}
-
-func (ks keyStorePlain) StoreKey(filename string, key *Key, auth string) error {
-	content, err := json.Marshal(key)
-	if err != nil {
-		return err
-	}
-	return writeKeyFile(filename, content)
-}
-
-func (ks keyStorePlain) JoinPath(filename string) string {
-	if filepath.IsAbs(filename) {
-		return filename
-	} else {
-		return filepath.Join(ks.keysDirPath, filename)
-	}
-}
--- a/accounts/key_store_test.go
+++ b/accounts/key_store_test.go
@@ -1,253 +0,0 @@
-// Copyright 2014 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package accounts
-
-import (
-	"crypto/rand"
-	"encoding/hex"
-	"fmt"
-	"io/ioutil"
-	"os"
-	"reflect"
-	"strings"
-	"testing"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/crypto"
-)
-
-func tmpKeyStore(t *testing.T, encrypted bool) (dir string, ks keyStore) {
-	d, err := ioutil.TempDir("", "geth-keystore-test")
-	if err != nil {
-		t.Fatal(err)
-	}
-	if encrypted {
-		ks = &keyStorePassphrase{d, veryLightScryptN, veryLightScryptP}
-	} else {
-		ks = &keyStorePlain{d}
-	}
-	return d, ks
-}
-
-func TestKeyStorePlain(t *testing.T) {
-	dir, ks := tmpKeyStore(t, false)
-	defer os.RemoveAll(dir)
-
-	pass := "" // not used but required by API
-	k1, account, err := storeNewKey(ks, rand.Reader, pass)
-	if err != nil {
-		t.Fatal(err)
-	}
-	k2, err := ks.GetKey(k1.Address, account.File, pass)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if !reflect.DeepEqual(k1.Address, k2.Address) {
-		t.Fatal(err)
-	}
-	if !reflect.DeepEqual(k1.PrivateKey, k2.PrivateKey) {
-		t.Fatal(err)
-	}
-}
-
-func TestKeyStorePassphrase(t *testing.T) {
-	dir, ks := tmpKeyStore(t, true)
-	defer os.RemoveAll(dir)
-
-	pass := "foo"
-	k1, account, err := storeNewKey(ks, rand.Reader, pass)
-	if err != nil {
-		t.Fatal(err)
-	}
-	k2, err := ks.GetKey(k1.Address, account.File, pass)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if !reflect.DeepEqual(k1.Address, k2.Address) {
-		t.Fatal(err)
-	}
-	if !reflect.DeepEqual(k1.PrivateKey, k2.PrivateKey) {
-		t.Fatal(err)
-	}
-}
-
-func TestKeyStorePassphraseDecryptionFail(t *testing.T) {
-	dir, ks := tmpKeyStore(t, true)
-	defer os.RemoveAll(dir)
-
-	pass := "foo"
-	k1, account, err := storeNewKey(ks, rand.Reader, pass)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if _, err = ks.GetKey(k1.Address, account.File, "bar"); err != ErrDecrypt {
-		t.Fatalf("wrong error for invalid passphrase\ngot %q\nwant %q", err, ErrDecrypt)
-	}
-}
-
-func TestImportPreSaleKey(t *testing.T) {
-	dir, ks := tmpKeyStore(t, true)
-	defer os.RemoveAll(dir)
-
-	// file content of a presale key file generated with:
-	// python pyethsaletool.py genwallet
-	// with password "foo"
-	fileContent := "{\"encseed\": \"26d87f5f2bf9835f9a47eefae571bc09f9107bb13d54ff12a4ec095d01f83897494cf34f7bed2ed34126ecba9db7b62de56c9d7cd136520a0427bfb11b8954ba7ac39b90d4650d3448e31185affcd74226a68f1e94b1108e6e0a4a91cdd83eba\", \"ethaddr\": \"d4584b5f6229b7be90727b0fc8c6b91bb427821f\", \"email\": \"gustav.simonsson@gmail.com\", \"btcaddr\": \"1EVknXyFC68kKNLkh6YnKzW41svSRoaAcx\"}"
-	pass := "foo"
-	account, _, err := importPreSaleKey(ks, []byte(fileContent), pass)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if account.Address != common.HexToAddress("d4584b5f6229b7be90727b0fc8c6b91bb427821f") {
-		t.Errorf("imported account has wrong address %x", account.Address)
-	}
-	if !strings.HasPrefix(account.File, dir) {
-		t.Errorf("imported account file not in keystore directory: %q", account.File)
-	}
-}
-
-// Test and utils for the key store tests in the Ethereum JSON tests;
-// testdataKeyStoreTests/basic_tests.json
-type KeyStoreTestV3 struct {
-	Json     encryptedKeyJSONV3
-	Password string
-	Priv     string
-}
-
-type KeyStoreTestV1 struct {
-	Json     encryptedKeyJSONV1
-	Password string
-	Priv     string
-}
-
-func TestV3_PBKDF2_1(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV3("testdata/v3_test_vector.json", t)
-	testDecryptV3(tests["wikipage_test_vector_pbkdf2"], t)
-}
-
-func TestV3_PBKDF2_2(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV3("../tests/files/KeyStoreTests/basic_tests.json", t)
-	testDecryptV3(tests["test1"], t)
-}
-
-func TestV3_PBKDF2_3(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV3("../tests/files/KeyStoreTests/basic_tests.json", t)
-	testDecryptV3(tests["python_generated_test_with_odd_iv"], t)
-}
-
-func TestV3_PBKDF2_4(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV3("../tests/files/KeyStoreTests/basic_tests.json", t)
-	testDecryptV3(tests["evilnonce"], t)
-}
-
-func TestV3_Scrypt_1(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV3("testdata/v3_test_vector.json", t)
-	testDecryptV3(tests["wikipage_test_vector_scrypt"], t)
-}
-
-func TestV3_Scrypt_2(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV3("../tests/files/KeyStoreTests/basic_tests.json", t)
-	testDecryptV3(tests["test2"], t)
-}
-
-func TestV1_1(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV1("testdata/v1_test_vector.json", t)
-	testDecryptV1(tests["test1"], t)
-}
-
-func TestV1_2(t *testing.T) {
-	t.Parallel()
-	ks := &keyStorePassphrase{"testdata/v1", LightScryptN, LightScryptP}
-	addr := common.HexToAddress("cb61d5a9c4896fb9658090b597ef0e7be6f7b67e")
-	file := "testdata/v1/cb61d5a9c4896fb9658090b597ef0e7be6f7b67e/cb61d5a9c4896fb9658090b597ef0e7be6f7b67e"
-	k, err := ks.GetKey(addr, file, "g")
-	if err != nil {
-		t.Fatal(err)
-	}
-	privHex := hex.EncodeToString(crypto.FromECDSA(k.PrivateKey))
-	expectedHex := "d1b1178d3529626a1a93e073f65028370d14c7eb0936eb42abef05db6f37ad7d"
-	if privHex != expectedHex {
-		t.Fatal(fmt.Errorf("Unexpected privkey: %v, expected %v", privHex, expectedHex))
-	}
-}
-
-func testDecryptV3(test KeyStoreTestV3, t *testing.T) {
-	privBytes, _, err := decryptKeyV3(&test.Json, test.Password)
-	if err != nil {
-		t.Fatal(err)
-	}
-	privHex := hex.EncodeToString(privBytes)
-	if test.Priv != privHex {
-		t.Fatal(fmt.Errorf("Decrypted bytes not equal to test, expected %v have %v", test.Priv, privHex))
-	}
-}
-
-func testDecryptV1(test KeyStoreTestV1, t *testing.T) {
-	privBytes, _, err := decryptKeyV1(&test.Json, test.Password)
-	if err != nil {
-		t.Fatal(err)
-	}
-	privHex := hex.EncodeToString(privBytes)
-	if test.Priv != privHex {
-		t.Fatal(fmt.Errorf("Decrypted bytes not equal to test, expected %v have %v", test.Priv, privHex))
-	}
-}
-
-func loadKeyStoreTestV3(file string, t *testing.T) map[string]KeyStoreTestV3 {
-	tests := make(map[string]KeyStoreTestV3)
-	err := common.LoadJSON(file, &tests)
-	if err != nil {
-		t.Fatal(err)
-	}
-	return tests
-}
-
-func loadKeyStoreTestV1(file string, t *testing.T) map[string]KeyStoreTestV1 {
-	tests := make(map[string]KeyStoreTestV1)
-	err := common.LoadJSON(file, &tests)
-	if err != nil {
-		t.Fatal(err)
-	}
-	return tests
-}
-
-func TestKeyForDirectICAP(t *testing.T) {
-	t.Parallel()
-	key := NewKeyForDirectICAP(rand.Reader)
-	if !strings.HasPrefix(key.Address.Hex(), "0x00") {
-		t.Errorf("Expected first address byte to be zero, have: %s", key.Address.Hex())
-	}
-}
-
-func TestV3_31_Byte_Key(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV3("testdata/v3_test_vector.json", t)
-	testDecryptV3(tests["31_byte_key"], t)
-}
-
-func TestV3_30_Byte_Key(t *testing.T) {
-	t.Parallel()
-	tests := loadKeyStoreTestV3("testdata/v3_test_vector.json", t)
-	testDecryptV3(tests["30_byte_key"], t)
-}
--- a/accounts/keystore/account_cache.go
+++ b/accounts/keystore/account_cache.go
@@ -0,0 +1,298 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package keystore
+
+import (
+	"bufio"
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/log"
+	"gopkg.in/fatih/set.v0"
+)
+
+// Minimum amount of time between cache reloads. This limit applies if the platform does
+// not support change notifications. It also applies if the keystore directory does not
+// exist yet, the code will attempt to create a watcher at most this often.
+const minReloadInterval = 2 * time.Second
+
+type accountsByURL []accounts.Account
+
+func (s accountsByURL) Len() int           { return len(s) }
+func (s accountsByURL) Less(i, j int) bool { return s[i].URL.Cmp(s[j].URL) < 0 }
+func (s accountsByURL) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// AmbiguousAddrError is returned when attempting to unlock
+// an address for which more than one file exists.
+type AmbiguousAddrError struct {
+	Addr    common.Address
+	Matches []accounts.Account
+}
+
+func (err *AmbiguousAddrError) Error() string {
+	files := ""
+	for i, a := range err.Matches {
+		files += a.URL.Path
+		if i < len(err.Matches)-1 {
+			files += ", "
+		}
+	}
+	return fmt.Sprintf("multiple keys match address (%s)", files)
+}
+
+// accountCache is a live index of all accounts in the keystore.
+type accountCache struct {
+	keydir   string
+	watcher  *watcher
+	mu       sync.Mutex
+	all      accountsByURL
+	byAddr   map[common.Address][]accounts.Account
+	throttle *time.Timer
+	notify   chan struct{}
+	fileC    fileCache
+}
+
+func newAccountCache(keydir string) (*accountCache, chan struct{}) {
+	ac := &accountCache{
+		keydir: keydir,
+		byAddr: make(map[common.Address][]accounts.Account),
+		notify: make(chan struct{}, 1),
+		fileC:  fileCache{all: set.NewNonTS()},
+	}
+	ac.watcher = newWatcher(ac)
+	return ac, ac.notify
+}
+
+func (ac *accountCache) accounts() []accounts.Account {
+	ac.maybeReload()
+	ac.mu.Lock()
+	defer ac.mu.Unlock()
+	cpy := make([]accounts.Account, len(ac.all))
+	copy(cpy, ac.all)
+	return cpy
+}
+
+func (ac *accountCache) hasAddress(addr common.Address) bool {
+	ac.maybeReload()
+	ac.mu.Lock()
+	defer ac.mu.Unlock()
+	return len(ac.byAddr[addr]) > 0
+}
+
+func (ac *accountCache) add(newAccount accounts.Account) {
+	ac.mu.Lock()
+	defer ac.mu.Unlock()
+
+	i := sort.Search(len(ac.all), func(i int) bool { return ac.all[i].URL.Cmp(newAccount.URL) >= 0 })
+	if i < len(ac.all) && ac.all[i] == newAccount {
+		return
+	}
+	// newAccount is not in the cache.
+	ac.all = append(ac.all, accounts.Account{})
+	copy(ac.all[i+1:], ac.all[i:])
+	ac.all[i] = newAccount
+	ac.byAddr[newAccount.Address] = append(ac.byAddr[newAccount.Address], newAccount)
+}
+
+// note: removed needs to be unique here (i.e. both File and Address must be set).
+func (ac *accountCache) delete(removed accounts.Account) {
+	ac.mu.Lock()
+	defer ac.mu.Unlock()
+
+	ac.all = removeAccount(ac.all, removed)
+	if ba := removeAccount(ac.byAddr[removed.Address], removed); len(ba) == 0 {
+		delete(ac.byAddr, removed.Address)
+	} else {
+		ac.byAddr[removed.Address] = ba
+	}
+}
+
+// deleteByFile removes an account referenced by the given path.
+func (ac *accountCache) deleteByFile(path string) {
+	ac.mu.Lock()
+	defer ac.mu.Unlock()
+	i := sort.Search(len(ac.all), func(i int) bool { return ac.all[i].URL.Path >= path })
+
+	if i < len(ac.all) && ac.all[i].URL.Path == path {
+		removed := ac.all[i]
+		ac.all = append(ac.all[:i], ac.all[i+1:]...)
+		if ba := removeAccount(ac.byAddr[removed.Address], removed); len(ba) == 0 {
+			delete(ac.byAddr, removed.Address)
+		} else {
+			ac.byAddr[removed.Address] = ba
+		}
+	}
+}
+
+func removeAccount(slice []accounts.Account, elem accounts.Account) []accounts.Account {
+	for i := range slice {
+		if slice[i] == elem {
+			return append(slice[:i], slice[i+1:]...)
+		}
+	}
+	return slice
+}
+
+// find returns the cached account for address if there is a unique match.
+// The exact matching rules are explained by the documentation of accounts.Account.
+// Callers must hold ac.mu.
+func (ac *accountCache) find(a accounts.Account) (accounts.Account, error) {
+	// Limit search to address candidates if possible.
+	matches := ac.all
+	if (a.Address != common.Address{}) {
+		matches = ac.byAddr[a.Address]
+	}
+	if a.URL.Path != "" {
+		// If only the basename is specified, complete the path.
+		if !strings.ContainsRune(a.URL.Path, filepath.Separator) {
+			a.URL.Path = filepath.Join(ac.keydir, a.URL.Path)
+		}
+		for i := range matches {
+			if matches[i].URL == a.URL {
+				return matches[i], nil
+			}
+		}
+		if (a.Address == common.Address{}) {
+			return accounts.Account{}, ErrNoMatch
+		}
+	}
+	switch len(matches) {
+	case 1:
+		return matches[0], nil
+	case 0:
+		return accounts.Account{}, ErrNoMatch
+	default:
+		err := &AmbiguousAddrError{Addr: a.Address, Matches: make([]accounts.Account, len(matches))}
+		copy(err.Matches, matches)
+		sort.Sort(accountsByURL(err.Matches))
+		return accounts.Account{}, err
+	}
+}
+
+func (ac *accountCache) maybeReload() {
+	ac.mu.Lock()
+
+	if ac.watcher.running {
+		ac.mu.Unlock()
+		return // A watcher is running and will keep the cache up-to-date.
+	}
+	if ac.throttle == nil {
+		ac.throttle = time.NewTimer(0)
+	} else {
+		select {
+		case <-ac.throttle.C:
+		default:
+			ac.mu.Unlock()
+			return // The cache was reloaded recently.
+		}
+	}
+	// No watcher running, start it.
+	ac.watcher.start()
+	ac.throttle.Reset(minReloadInterval)
+	ac.mu.Unlock()
+	ac.scanAccounts()
+}
+
+func (ac *accountCache) close() {
+	ac.mu.Lock()
+	ac.watcher.close()
+	if ac.throttle != nil {
+		ac.throttle.Stop()
+	}
+	if ac.notify != nil {
+		close(ac.notify)
+		ac.notify = nil
+	}
+	ac.mu.Unlock()
+}
+
+// scanAccounts checks if any changes have occurred on the filesystem, and
+// updates the account cache accordingly
+func (ac *accountCache) scanAccounts() error {
+	// Scan the entire folder metadata for file changes
+	creates, deletes, updates, err := ac.fileC.scan(ac.keydir)
+	if err != nil {
+		log.Debug("Failed to reload keystore contents", "err", err)
+		return err
+	}
+	if creates.Size() == 0 && deletes.Size() == 0 && updates.Size() == 0 {
+		return nil
+	}
+	// Create a helper method to scan the contents of the key files
+	var (
+		buf = new(bufio.Reader)
+		key struct {
+			Address string `json:"address"`
+		}
+	)
+	readAccount := func(path string) *accounts.Account {
+		fd, err := os.Open(path)
+		if err != nil {
+			log.Trace("Failed to open keystore file", "path", path, "err", err)
+			return nil
+		}
+		defer fd.Close()
+		buf.Reset(fd)
+		// Parse the address.
+		key.Address = ""
+		err = json.NewDecoder(buf).Decode(&key)
+		addr := common.HexToAddress(key.Address)
+		switch {
+		case err != nil:
+			log.Debug("Failed to decode keystore key", "path", path, "err", err)
+		case (addr == common.Address{}):
+			log.Debug("Failed to decode keystore key", "path", path, "err", "missing or zero address")
+		default:
+			return &accounts.Account{Address: addr, URL: accounts.URL{Scheme: KeyStoreScheme, Path: path}}
+		}
+		return nil
+	}
+	// Process all the file diffs
+	start := time.Now()
+
+	for _, p := range creates.List() {
+		if a := readAccount(p.(string)); a != nil {
+			ac.add(*a)
+		}
+	}
+	for _, p := range deletes.List() {
+		ac.deleteByFile(p.(string))
+	}
+	for _, p := range updates.List() {
+		path := p.(string)
+		ac.deleteByFile(path)
+		if a := readAccount(path); a != nil {
+			ac.add(*a)
+		}
+	}
+	end := time.Now()
+
+	select {
+	case ac.notify <- struct{}{}:
+	default:
+	}
+	log.Trace("Handled keystore changes", "time", end.Sub(start))
+	return nil
+}
--- a/accounts/keystore/account_cache_test.go
+++ b/accounts/keystore/account_cache_test.go
@@ -0,0 +1,406 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package keystore
+
+import (
+	"fmt"
+	"io/ioutil"
+	"math/rand"
+	"os"
+	"path/filepath"
+	"reflect"
+	"sort"
+	"testing"
+	"time"
+
+	"github.com/cespare/cp"
+	"github.com/davecgh/go-spew/spew"
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/common"
+)
+
+var (
+	cachetestDir, _   = filepath.Abs(filepath.Join("testdata", "keystore"))
+	cachetestAccounts = []accounts.Account{
+		{
+			Address: common.HexToAddress("7ef5a6135f1fd6a02593eedc869c6d41d934aef8"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(cachetestDir, "UTC--2016-03-22T12-57-55.920751759Z--7ef5a6135f1fd6a02593eedc869c6d41d934aef8")},
+		},
+		{
+			Address: common.HexToAddress("f466859ead1932d743d622cb74fc058882e8648a"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(cachetestDir, "aaa")},
+		},
+		{
+			Address: common.HexToAddress("289d485d9771714cce91d3393d764e1311907acc"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(cachetestDir, "zzz")},
+		},
+	}
+)
+
+func TestWatchNewFile(t *testing.T) {
+	t.Parallel()
+
+	dir, ks := tmpKeyStore(t, false)
+	defer os.RemoveAll(dir)
+
+	// Ensure the watcher is started before adding any files.
+	ks.Accounts()
+	time.Sleep(1000 * time.Millisecond)
+
+	// Move in the files.
+	wantAccounts := make([]accounts.Account, len(cachetestAccounts))
+	for i := range cachetestAccounts {
+		wantAccounts[i] = accounts.Account{
+			Address: cachetestAccounts[i].Address,
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(dir, filepath.Base(cachetestAccounts[i].URL.Path))},
+		}
+		if err := cp.CopyFile(wantAccounts[i].URL.Path, cachetestAccounts[i].URL.Path); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	// ks should see the accounts.
+	var list []accounts.Account
+	for d := 200 * time.Millisecond; d < 5*time.Second; d *= 2 {
+		list = ks.Accounts()
+		if reflect.DeepEqual(list, wantAccounts) {
+			// ks should have also received change notifications
+			select {
+			case <-ks.changes:
+			default:
+				t.Fatalf("wasn't notified of new accounts")
+			}
+			return
+		}
+		time.Sleep(d)
+	}
+	t.Errorf("got %s, want %s", spew.Sdump(list), spew.Sdump(wantAccounts))
+}
+
+func TestWatchNoDir(t *testing.T) {
+	t.Parallel()
+
+	// Create ks but not the directory that it watches.
+	rand.Seed(time.Now().UnixNano())
+	dir := filepath.Join(os.TempDir(), fmt.Sprintf("eth-keystore-watch-test-%d-%d", os.Getpid(), rand.Int()))
+	ks := NewKeyStore(dir, LightScryptN, LightScryptP)
+
+	list := ks.Accounts()
+	if len(list) > 0 {
+		t.Error("initial account list not empty:", list)
+	}
+	time.Sleep(100 * time.Millisecond)
+
+	// Create the directory and copy a key file into it.
+	os.MkdirAll(dir, 0700)
+	defer os.RemoveAll(dir)
+	file := filepath.Join(dir, "aaa")
+	if err := cp.CopyFile(file, cachetestAccounts[0].URL.Path); err != nil {
+		t.Fatal(err)
+	}
+
+	// ks should see the account.
+	wantAccounts := []accounts.Account{cachetestAccounts[0]}
+	wantAccounts[0].URL = accounts.URL{Scheme: KeyStoreScheme, Path: file}
+	for d := 200 * time.Millisecond; d < 8*time.Second; d *= 2 {
+		list = ks.Accounts()
+		if reflect.DeepEqual(list, wantAccounts) {
+			// ks should have also received change notifications
+			select {
+			case <-ks.changes:
+			default:
+				t.Fatalf("wasn't notified of new accounts")
+			}
+			return
+		}
+		time.Sleep(d)
+	}
+	t.Errorf("\ngot  %v\nwant %v", list, wantAccounts)
+}
+
+func TestCacheInitialReload(t *testing.T) {
+	cache, _ := newAccountCache(cachetestDir)
+	accounts := cache.accounts()
+	if !reflect.DeepEqual(accounts, cachetestAccounts) {
+		t.Fatalf("got initial accounts: %swant %s", spew.Sdump(accounts), spew.Sdump(cachetestAccounts))
+	}
+}
+
+func TestCacheAddDeleteOrder(t *testing.T) {
+	cache, _ := newAccountCache("testdata/no-such-dir")
+	cache.watcher.running = true // prevent unexpected reloads
+
+	accs := []accounts.Account{
+		{
+			Address: common.HexToAddress("095e7baea6a6c7c4c2dfeb977efac326af552d87"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: "-309830980"},
+		},
+		{
+			Address: common.HexToAddress("2cac1adea150210703ba75ed097ddfe24e14f213"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: "ggg"},
+		},
+		{
+			Address: common.HexToAddress("8bda78331c916a08481428e4b07c96d3e916d165"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: "zzzzzz-the-very-last-one.keyXXX"},
+		},
+		{
+			Address: common.HexToAddress("d49ff4eeb0b2686ed89c0fc0f2b6ea533ddbbd5e"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: "SOMETHING.key"},
+		},
+		{
+			Address: common.HexToAddress("7ef5a6135f1fd6a02593eedc869c6d41d934aef8"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: "UTC--2016-03-22T12-57-55.920751759Z--7ef5a6135f1fd6a02593eedc869c6d41d934aef8"},
+		},
+		{
+			Address: common.HexToAddress("f466859ead1932d743d622cb74fc058882e8648a"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: "aaa"},
+		},
+		{
+			Address: common.HexToAddress("289d485d9771714cce91d3393d764e1311907acc"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: "zzz"},
+		},
+	}
+	for _, a := range accs {
+		cache.add(a)
+	}
+	// Add some of them twice to check that they don't get reinserted.
+	cache.add(accs[0])
+	cache.add(accs[2])
+
+	// Check that the account list is sorted by filename.
+	wantAccounts := make([]accounts.Account, len(accs))
+	copy(wantAccounts, accs)
+	sort.Sort(accountsByURL(wantAccounts))
+	list := cache.accounts()
+	if !reflect.DeepEqual(list, wantAccounts) {
+		t.Fatalf("got accounts: %s\nwant %s", spew.Sdump(accs), spew.Sdump(wantAccounts))
+	}
+	for _, a := range accs {
+		if !cache.hasAddress(a.Address) {
+			t.Errorf("expected hasAccount(%x) to return true", a.Address)
+		}
+	}
+	if cache.hasAddress(common.HexToAddress("fd9bd350f08ee3c0c19b85a8e16114a11a60aa4e")) {
+		t.Errorf("expected hasAccount(%x) to return false", common.HexToAddress("fd9bd350f08ee3c0c19b85a8e16114a11a60aa4e"))
+	}
+
+	// Delete a few keys from the cache.
+	for i := 0; i < len(accs); i += 2 {
+		cache.delete(wantAccounts[i])
+	}
+	cache.delete(accounts.Account{Address: common.HexToAddress("fd9bd350f08ee3c0c19b85a8e16114a11a60aa4e"), URL: accounts.URL{Scheme: KeyStoreScheme, Path: "something"}})
+
+	// Check content again after deletion.
+	wantAccountsAfterDelete := []accounts.Account{
+		wantAccounts[1],
+		wantAccounts[3],
+		wantAccounts[5],
+	}
+	list = cache.accounts()
+	if !reflect.DeepEqual(list, wantAccountsAfterDelete) {
+		t.Fatalf("got accounts after delete: %s\nwant %s", spew.Sdump(list), spew.Sdump(wantAccountsAfterDelete))
+	}
+	for _, a := range wantAccountsAfterDelete {
+		if !cache.hasAddress(a.Address) {
+			t.Errorf("expected hasAccount(%x) to return true", a.Address)
+		}
+	}
+	if cache.hasAddress(wantAccounts[0].Address) {
+		t.Errorf("expected hasAccount(%x) to return false", wantAccounts[0].Address)
+	}
+}
+
+func TestCacheFind(t *testing.T) {
+	dir := filepath.Join("testdata", "dir")
+	cache, _ := newAccountCache(dir)
+	cache.watcher.running = true // prevent unexpected reloads
+
+	accs := []accounts.Account{
+		{
+			Address: common.HexToAddress("095e7baea6a6c7c4c2dfeb977efac326af552d87"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(dir, "a.key")},
+		},
+		{
+			Address: common.HexToAddress("2cac1adea150210703ba75ed097ddfe24e14f213"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(dir, "b.key")},
+		},
+		{
+			Address: common.HexToAddress("d49ff4eeb0b2686ed89c0fc0f2b6ea533ddbbd5e"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(dir, "c.key")},
+		},
+		{
+			Address: common.HexToAddress("d49ff4eeb0b2686ed89c0fc0f2b6ea533ddbbd5e"),
+			URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(dir, "c2.key")},
+		},
+	}
+	for _, a := range accs {
+		cache.add(a)
+	}
+
+	nomatchAccount := accounts.Account{
+		Address: common.HexToAddress("f466859ead1932d743d622cb74fc058882e8648a"),
+		URL:     accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Join(dir, "something")},
+	}
+	tests := []struct {
+		Query      accounts.Account
+		WantResult accounts.Account
+		WantError  error
+	}{
+		// by address
+		{Query: accounts.Account{Address: accs[0].Address}, WantResult: accs[0]},
+		// by file
+		{Query: accounts.Account{URL: accs[0].URL}, WantResult: accs[0]},
+		// by basename
+		{Query: accounts.Account{URL: accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Base(accs[0].URL.Path)}}, WantResult: accs[0]},
+		// by file and address
+		{Query: accs[0], WantResult: accs[0]},
+		// ambiguous address, tie resolved by file
+		{Query: accs[2], WantResult: accs[2]},
+		// ambiguous address error
+		{
+			Query: accounts.Account{Address: accs[2].Address},
+			WantError: &AmbiguousAddrError{
+				Addr:    accs[2].Address,
+				Matches: []accounts.Account{accs[2], accs[3]},
+			},
+		},
+		// no match error
+		{Query: nomatchAccount, WantError: ErrNoMatch},
+		{Query: accounts.Account{URL: nomatchAccount.URL}, WantError: ErrNoMatch},
+		{Query: accounts.Account{URL: accounts.URL{Scheme: KeyStoreScheme, Path: filepath.Base(nomatchAccount.URL.Path)}}, WantError: ErrNoMatch},
+		{Query: accounts.Account{Address: nomatchAccount.Address}, WantError: ErrNoMatch},
+	}
+	for i, test := range tests {
+		a, err := cache.find(test.Query)
+		if !reflect.DeepEqual(err, test.WantError) {
+			t.Errorf("test %d: error mismatch for query %v\ngot %q\nwant %q", i, test.Query, err, test.WantError)
+			continue
+		}
+		if a != test.WantResult {
+			t.Errorf("test %d: result mismatch for query %v\ngot %v\nwant %v", i, test.Query, a, test.WantResult)
+			continue
+		}
+	}
+}
+
+func waitForAccounts(wantAccounts []accounts.Account, ks *KeyStore) error {
+	var list []accounts.Account
+	for d := 200 * time.Millisecond; d < 8*time.Second; d *= 2 {
+		list = ks.Accounts()
+		if reflect.DeepEqual(list, wantAccounts) {
+			// ks should have also received change notifications
+			select {
+			case <-ks.changes:
+			default:
+				return fmt.Errorf("wasn't notified of new accounts")
+			}
+			return nil
+		}
+		time.Sleep(d)
+	}
+	return fmt.Errorf("\ngot  %v\nwant %v", list, wantAccounts)
+}
+
+// TestUpdatedKeyfileContents tests that updating the contents of a keystore file
+// is noticed by the watcher, and the account cache is updated accordingly
+func TestUpdatedKeyfileContents(t *testing.T) {
+	t.Parallel()
+
+	// Create a temporary kesytore to test with
+	rand.Seed(time.Now().UnixNano())
+	dir := filepath.Join(os.TempDir(), fmt.Sprintf("eth-keystore-watch-test-%d-%d", os.Getpid(), rand.Int()))
+	ks := NewKeyStore(dir, LightScryptN, LightScryptP)
+
+	list := ks.Accounts()
+	if len(list) > 0 {
+		t.Error("initial account list not empty:", list)
+	}
+	time.Sleep(100 * time.Millisecond)
+
+	// Create the directory and copy a key file into it.
+	os.MkdirAll(dir, 0700)
+	defer os.RemoveAll(dir)
+	file := filepath.Join(dir, "aaa")
+
+	// Place one of our testfiles in there
+	if err := cp.CopyFile(file, cachetestAccounts[0].URL.Path); err != nil {
+		t.Fatal(err)
+	}
+
+	// ks should see the account.
+	wantAccounts := []accounts.Account{cachetestAccounts[0]}
+	wantAccounts[0].URL = accounts.URL{Scheme: KeyStoreScheme, Path: file}
+	if err := waitForAccounts(wantAccounts, ks); err != nil {
+		t.Error(err)
+		return
+	}
+
+	// needed so that modTime of `file` is different to its current value after forceCopyFile
+	time.Sleep(1000 * time.Millisecond)
+
+	// Now replace file contents
+	if err := forceCopyFile(file, cachetestAccounts[1].URL.Path); err != nil {
+		t.Fatal(err)
+		return
+	}
+	wantAccounts = []accounts.Account{cachetestAccounts[1]}
+	wantAccounts[0].URL = accounts.URL{Scheme: KeyStoreScheme, Path: file}
+	if err := waitForAccounts(wantAccounts, ks); err != nil {
+		t.Errorf("First replacement failed")
+		t.Error(err)
+		return
+	}
+
+	// needed so that modTime of `file` is different to its current value after forceCopyFile
+	time.Sleep(1000 * time.Millisecond)
+
+	// Now replace file contents again
+	if err := forceCopyFile(file, cachetestAccounts[2].URL.Path); err != nil {
+		t.Fatal(err)
+		return
+	}
+	wantAccounts = []accounts.Account{cachetestAccounts[2]}
+	wantAccounts[0].URL = accounts.URL{Scheme: KeyStoreScheme, Path: file}
+	if err := waitForAccounts(wantAccounts, ks); err != nil {
+		t.Errorf("Second replacement failed")
+		t.Error(err)
+		return
+	}
+
+	// needed so that modTime of `file` is different to its current value after ioutil.WriteFile
+	time.Sleep(1000 * time.Millisecond)
+
+	// Now replace file contents with crap
+	if err := ioutil.WriteFile(file, []byte("foo"), 0644); err != nil {
+		t.Fatal(err)
+		return
+	}
+	if err := waitForAccounts([]accounts.Account{}, ks); err != nil {
+		t.Errorf("Emptying account file failed")
+		t.Error(err)
+		return
+	}
+}
+
+// forceCopyFile is like cp.CopyFile, but doesn't complain if the destination exists.
+func forceCopyFile(dst, src string) error {
+	data, err := ioutil.ReadFile(src)
+	if err != nil {
+		return err
+	}
+	return ioutil.WriteFile(dst, data, 0644)
+}
--- a/accounts/keystore/file_cache.go
+++ b/accounts/keystore/file_cache.go
@@ -0,0 +1,102 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package keystore
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/ethereum/go-ethereum/log"
+	set "gopkg.in/fatih/set.v0"
+)
+
+// fileCache is a cache of files seen during scan of keystore.
+type fileCache struct {
+	all     *set.SetNonTS // Set of all files from the keystore folder
+	lastMod time.Time     // Last time instance when a file was modified
+	mu      sync.RWMutex
+}
+
+// scan performs a new scan on the given directory, compares against the already
+// cached filenames, and returns file sets: creates, deletes, updates.
+func (fc *fileCache) scan(keyDir string) (set.Interface, set.Interface, set.Interface, error) {
+	t0 := time.Now()
+
+	// List all the failes from the keystore folder
+	files, err := ioutil.ReadDir(keyDir)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	t1 := time.Now()
+
+	fc.mu.Lock()
+	defer fc.mu.Unlock()
+
+	// Iterate all the files and gather their metadata
+	all := set.NewNonTS()
+	mods := set.NewNonTS()
+
+	var newLastMod time.Time
+	for _, fi := range files {
+		// Skip any non-key files from the folder
+		path := filepath.Join(keyDir, fi.Name())
+		if skipKeyFile(fi) {
+			log.Trace("Ignoring file on account scan", "path", path)
+			continue
+		}
+		// Gather the set of all and fresly modified files
+		all.Add(path)
+
+		modified := fi.ModTime()
+		if modified.After(fc.lastMod) {
+			mods.Add(path)
+		}
+		if modified.After(newLastMod) {
+			newLastMod = modified
+		}
+	}
+	t2 := time.Now()
+
+	// Update the tracked files and return the three sets
+	deletes := set.Difference(fc.all, all)   // Deletes = previous - current
+	creates := set.Difference(all, fc.all)   // Creates = current - previous
+	updates := set.Difference(mods, creates) // Updates = modified - creates
+
+	fc.all, fc.lastMod = all, newLastMod
+	t3 := time.Now()
+
+	// Report on the scanning stats and return
+	log.Debug("FS scan times", "list", t1.Sub(t0), "set", t2.Sub(t1), "diff", t3.Sub(t2))
+	return creates, deletes, updates, nil
+}
+
+// skipKeyFile ignores editor backups, hidden files and folders/symlinks.
+func skipKeyFile(fi os.FileInfo) bool {
+	// Skip editor backups and UNIX-style hidden files.
+	if strings.HasSuffix(fi.Name(), "~") || strings.HasPrefix(fi.Name(), ".") {
+		return true
+	}
+	// Skip misc special files, directories (yes, symlinks too).
+	if fi.IsDir() || fi.Mode()&os.ModeType != 0 {
+		return true
+	}
+	return false
+}
--- a/accounts/keystore/key.go
+++ b/accounts/keystore/key.go
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

-package accounts
+package keystore

 import (
 	"bytes"
@@ -29,9 +29,9 @@ import (
 	"strings"
 	"time"

+	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/crypto/secp256k1"
 	"github.com/pborman/uuid"
 )

@@ -91,14 +91,6 @@ type cipherparamsJSON struct {
 	IV string `json:"iv"`
 }

-type scryptParamsJSON struct {
-	N     int    `json:"n"`
-	R     int    `json:"r"`
-	P     int    `json:"p"`
-	DkLen int    `json:"dklen"`
-	Salt  string `json:"salt"`
-}
-
 func (k *Key) MarshalJSON() (j []byte, err error) {
 	jStruct := plainKeyJSON{
 		hex.EncodeToString(k.Address[:]),
@@ -124,14 +116,13 @@ func (k *Key) UnmarshalJSON(j []byte) (err error) {
 	if err != nil {
 		return err
 	}
-
-	privkey, err := hex.DecodeString(keyJSON.PrivateKey)
+	privkey, err := crypto.HexToECDSA(keyJSON.PrivateKey)
 	if err != nil {
 		return err
 	}

 	k.Address = common.BytesToAddress(addr)
-	k.PrivateKey = crypto.ToECDSA(privkey)
+	k.PrivateKey = privkey

 	return nil
 }
@@ -156,7 +147,7 @@ func NewKeyForDirectICAP(rand io.Reader) *Key {
 		panic("key generation: could not read from random source: " + err.Error())
 	}
 	reader := bytes.NewReader(randBytes)
-	privateKeyECDSA, err := ecdsa.GenerateKey(secp256k1.S256(), reader)
+	privateKeyECDSA, err := ecdsa.GenerateKey(crypto.S256(), reader)
 	if err != nil {
 		panic("key generation: ecdsa.GenerateKey failed: " + err.Error())
 	}
@@ -168,20 +159,20 @@ func NewKeyForDirectICAP(rand io.Reader) *Key {
 }

 func newKey(rand io.Reader) (*Key, error) {
-	privateKeyECDSA, err := ecdsa.GenerateKey(secp256k1.S256(), rand)
+	privateKeyECDSA, err := ecdsa.GenerateKey(crypto.S256(), rand)
 	if err != nil {
 		return nil, err
 	}
 	return newKeyFromECDSA(privateKeyECDSA), nil
 }

-func storeNewKey(ks keyStore, rand io.Reader, auth string) (*Key, Account, error) {
+func storeNewKey(ks keyStore, rand io.Reader, auth string) (*Key, accounts.Account, error) {
 	key, err := newKey(rand)
 	if err != nil {
-		return nil, Account{}, err
+		return nil, accounts.Account{}, err
 	}
-	a := Account{Address: key.Address, File: ks.JoinPath(keyFileName(key.Address))}
-	if err := ks.StoreKey(a.File, key, auth); err != nil {
+	a := accounts.Account{Address: key.Address, URL: accounts.URL{Scheme: KeyStoreScheme, Path: ks.JoinPath(keyFileName(key.Address))}}
+	if err := ks.StoreKey(a.URL.Path, key, auth); err != nil {
 		zeroKey(key.PrivateKey)
 		return nil, a, err
 	}
--- a/accounts/keystore/keystore.go
+++ b/accounts/keystore/keystore.go
@@ -0,0 +1,493 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// Package keystore implements encrypted storage of secp256k1 private keys.
+//
+// Keys are stored as encrypted JSON files according to the Web3 Secret Storage specification.
+// See https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition for more information.
+package keystore
+
+import (
+	"crypto/ecdsa"
+	crand "crypto/rand"
+	"errors"
+	"fmt"
+	"math/big"
+	"os"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"sync"
+	"time"
+
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/event"
+)
+
+var (
+	ErrLocked  = accounts.NewAuthNeededError("password or unlock")
+	ErrNoMatch = errors.New("no key for given address or file")
+	ErrDecrypt = errors.New("could not decrypt key with given passphrase")
+)
+
+// KeyStoreType is the reflect type of a keystore backend.
+var KeyStoreType = reflect.TypeOf(&KeyStore{})
+
+// KeyStoreScheme is the protocol scheme prefixing account and wallet URLs.
+var KeyStoreScheme = "keystore"
+
+// Maximum time between wallet refreshes (if filesystem notifications don't work).
+const walletRefreshCycle = 3 * time.Second
+
+// KeyStore manages a key storage directory on disk.
+type KeyStore struct {
+	storage  keyStore                     // Storage backend, might be cleartext or encrypted
+	cache    *accountCache                // In-memory account cache over the filesystem storage
+	changes  chan struct{}                // Channel receiving change notifications from the cache
+	unlocked map[common.Address]*unlocked // Currently unlocked account (decrypted private keys)
+
+	wallets     []accounts.Wallet       // Wallet wrappers around the individual key files
+	updateFeed  event.Feed              // Event feed to notify wallet additions/removals
+	updateScope event.SubscriptionScope // Subscription scope tracking current live listeners
+	updating    bool                    // Whether the event notification loop is running
+
+	mu sync.RWMutex
+}
+
+type unlocked struct {
+	*Key
+	abort chan struct{}
+}
+
+// NewKeyStore creates a keystore for the given directory.
+func NewKeyStore(keydir string, scryptN, scryptP int) *KeyStore {
+	keydir, _ = filepath.Abs(keydir)
+	ks := &KeyStore{storage: &keyStorePassphrase{keydir, scryptN, scryptP}}
+	ks.init(keydir)
+	return ks
+}
+
+// NewPlaintextKeyStore creates a keystore for the given directory.
+// Deprecated: Use NewKeyStore.
+func NewPlaintextKeyStore(keydir string) *KeyStore {
+	keydir, _ = filepath.Abs(keydir)
+	ks := &KeyStore{storage: &keyStorePlain{keydir}}
+	ks.init(keydir)
+	return ks
+}
+
+func (ks *KeyStore) init(keydir string) {
+	// Lock the mutex since the account cache might call back with events
+	ks.mu.Lock()
+	defer ks.mu.Unlock()
+
+	// Initialize the set of unlocked keys and the account cache
+	ks.unlocked = make(map[common.Address]*unlocked)
+	ks.cache, ks.changes = newAccountCache(keydir)
+
+	// TODO: In order for this finalizer to work, there must be no references
+	// to ks. addressCache doesn't keep a reference but unlocked keys do,
+	// so the finalizer will not trigger until all timed unlocks have expired.
+	runtime.SetFinalizer(ks, func(m *KeyStore) {
+		m.cache.close()
+	})
+	// Create the initial list of wallets from the cache
+	accs := ks.cache.accounts()
+	ks.wallets = make([]accounts.Wallet, len(accs))
+	for i := 0; i < len(accs); i++ {
+		ks.wallets[i] = &keystoreWallet{account: accs[i], keystore: ks}
+	}
+}
+
+// Wallets implements accounts.Backend, returning all single-key wallets from the
+// keystore directory.
+func (ks *KeyStore) Wallets() []accounts.Wallet {
+	// Make sure the list of wallets is in sync with the account cache
+	ks.refreshWallets()
+
+	ks.mu.RLock()
+	defer ks.mu.RUnlock()
+
+	cpy := make([]accounts.Wallet, len(ks.wallets))
+	copy(cpy, ks.wallets)
+	return cpy
+}
+
+// refreshWallets retrieves the current account list and based on that does any
+// necessary wallet refreshes.
+func (ks *KeyStore) refreshWallets() {
+	// Retrieve the current list of accounts
+	ks.mu.Lock()
+	accs := ks.cache.accounts()
+
+	// Transform the current list of wallets into the new one
+	wallets := make([]accounts.Wallet, 0, len(accs))
+	events := []accounts.WalletEvent{}
+
+	for _, account := range accs {
+		// Drop wallets while they were in front of the next account
+		for len(ks.wallets) > 0 && ks.wallets[0].URL().Cmp(account.URL) < 0 {
+			events = append(events, accounts.WalletEvent{Wallet: ks.wallets[0], Kind: accounts.WalletDropped})
+			ks.wallets = ks.wallets[1:]
+		}
+		// If there are no more wallets or the account is before the next, wrap new wallet
+		if len(ks.wallets) == 0 || ks.wallets[0].URL().Cmp(account.URL) > 0 {
+			wallet := &keystoreWallet{account: account, keystore: ks}
+
+			events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletArrived})
+			wallets = append(wallets, wallet)
+			continue
+		}
+		// If the account is the same as the first wallet, keep it
+		if ks.wallets[0].Accounts()[0] == account {
+			wallets = append(wallets, ks.wallets[0])
+			ks.wallets = ks.wallets[1:]
+			continue
+		}
+	}
+	// Drop any leftover wallets and set the new batch
+	for _, wallet := range ks.wallets {
+		events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletDropped})
+	}
+	ks.wallets = wallets
+	ks.mu.Unlock()
+
+	// Fire all wallet events and return
+	for _, event := range events {
+		ks.updateFeed.Send(event)
+	}
+}
+
+// Subscribe implements accounts.Backend, creating an async subscription to
+// receive notifications on the addition or removal of keystore wallets.
+func (ks *KeyStore) Subscribe(sink chan<- accounts.WalletEvent) event.Subscription {
+	// We need the mutex to reliably start/stop the update loop
+	ks.mu.Lock()
+	defer ks.mu.Unlock()
+
+	// Subscribe the caller and track the subscriber count
+	sub := ks.updateScope.Track(ks.updateFeed.Subscribe(sink))
+
+	// Subscribers require an active notification loop, start it
+	if !ks.updating {
+		ks.updating = true
+		go ks.updater()
+	}
+	return sub
+}
+
+// updater is responsible for maintaining an up-to-date list of wallets stored in
+// the keystore, and for firing wallet addition/removal events. It listens for
+// account change events from the underlying account cache, and also periodically
+// forces a manual refresh (only triggers for systems where the filesystem notifier
+// is not running).
+func (ks *KeyStore) updater() {
+	for {
+		// Wait for an account update or a refresh timeout
+		select {
+		case <-ks.changes:
+		case <-time.After(walletRefreshCycle):
+		}
+		// Run the wallet refresher
+		ks.refreshWallets()
+
+		// If all our subscribers left, stop the updater
+		ks.mu.Lock()
+		if ks.updateScope.Count() == 0 {
+			ks.updating = false
+			ks.mu.Unlock()
+			return
+		}
+		ks.mu.Unlock()
+	}
+}
+
+// HasAddress reports whether a key with the given address is present.
+func (ks *KeyStore) HasAddress(addr common.Address) bool {
+	return ks.cache.hasAddress(addr)
+}
+
+// Accounts returns all key files present in the directory.
+func (ks *KeyStore) Accounts() []accounts.Account {
+	return ks.cache.accounts()
+}
+
+// Delete deletes the key matched by account if the passphrase is correct.
+// If the account contains no filename, the address must match a unique key.
+func (ks *KeyStore) Delete(a accounts.Account, passphrase string) error {
+	// Decrypting the key isn't really necessary, but we do
+	// it anyway to check the password and zero out the key
+	// immediately afterwards.
+	a, key, err := ks.getDecryptedKey(a, passphrase)
+	if key != nil {
+		zeroKey(key.PrivateKey)
+	}
+	if err != nil {
+		return err
+	}
+	// The order is crucial here. The key is dropped from the
+	// cache after the file is gone so that a reload happening in
+	// between won't insert it into the cache again.
+	err = os.Remove(a.URL.Path)
+	if err == nil {
+		ks.cache.delete(a)
+		ks.refreshWallets()
+	}
+	return err
+}
+
+// SignHash calculates a ECDSA signature for the given hash. The produced
+// signature is in the [R || S || V] format where V is 0 or 1.
+func (ks *KeyStore) SignHash(a accounts.Account, hash []byte) ([]byte, error) {
+	// Look up the key to sign with and abort if it cannot be found
+	ks.mu.RLock()
+	defer ks.mu.RUnlock()
+
+	unlockedKey, found := ks.unlocked[a.Address]
+	if !found {
+		return nil, ErrLocked
+	}
+	// Sign the hash using plain ECDSA operations
+	return crypto.Sign(hash, unlockedKey.PrivateKey)
+}
+
+// SignTx signs the given transaction with the requested account.
+func (ks *KeyStore) SignTx(a accounts.Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
+	// Look up the key to sign with and abort if it cannot be found
+	ks.mu.RLock()
+	defer ks.mu.RUnlock()
+
+	unlockedKey, found := ks.unlocked[a.Address]
+	if !found {
+		return nil, ErrLocked
+	}
+	// Depending on the presence of the chain ID, sign with EIP155 or homestead
+	if chainID != nil {
+		return types.SignTx(tx, types.NewEIP155Signer(chainID), unlockedKey.PrivateKey)
+	}
+	return types.SignTx(tx, types.HomesteadSigner{}, unlockedKey.PrivateKey)
+}
+
+// SignHashWithPassphrase signs hash if the private key matching the given address
+// can be decrypted with the given passphrase. The produced signature is in the
+// [R || S || V] format where V is 0 or 1.
+func (ks *KeyStore) SignHashWithPassphrase(a accounts.Account, passphrase string, hash []byte) (signature []byte, err error) {
+	_, key, err := ks.getDecryptedKey(a, passphrase)
+	if err != nil {
+		return nil, err
+	}
+	defer zeroKey(key.PrivateKey)
+	return crypto.Sign(hash, key.PrivateKey)
+}
+
+// SignTxWithPassphrase signs the transaction if the private key matching the
+// given address can be decrypted with the given passphrase.
+func (ks *KeyStore) SignTxWithPassphrase(a accounts.Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
+	_, key, err := ks.getDecryptedKey(a, passphrase)
+	if err != nil {
+		return nil, err
+	}
+	defer zeroKey(key.PrivateKey)
+
+	// Depending on the presence of the chain ID, sign with EIP155 or homestead
+	if chainID != nil {
+		return types.SignTx(tx, types.NewEIP155Signer(chainID), key.PrivateKey)
+	}
+	return types.SignTx(tx, types.HomesteadSigner{}, key.PrivateKey)
+}
+
+// Unlock unlocks the given account indefinitely.
+func (ks *KeyStore) Unlock(a accounts.Account, passphrase string) error {
+	return ks.TimedUnlock(a, passphrase, 0)
+}
+
+// Lock removes the private key with the given address from memory.
+func (ks *KeyStore) Lock(addr common.Address) error {
+	ks.mu.Lock()
+	if unl, found := ks.unlocked[addr]; found {
+		ks.mu.Unlock()
+		ks.expire(addr, unl, time.Duration(0)*time.Nanosecond)
+	} else {
+		ks.mu.Unlock()
+	}
+	return nil
+}
+
+// TimedUnlock unlocks the given account with the passphrase. The account
+// stays unlocked for the duration of timeout. A timeout of 0 unlocks the account
+// until the program exits. The account must match a unique key file.
+//
+// If the account address is already unlocked for a duration, TimedUnlock extends or
+// shortens the active unlock timeout. If the address was previously unlocked
+// indefinitely the timeout is not altered.
+func (ks *KeyStore) TimedUnlock(a accounts.Account, passphrase string, timeout time.Duration) error {
+	a, key, err := ks.getDecryptedKey(a, passphrase)
+	if err != nil {
+		return err
+	}
+
+	ks.mu.Lock()
+	defer ks.mu.Unlock()
+	u, found := ks.unlocked[a.Address]
+	if found {
+		if u.abort == nil {
+			// The address was unlocked indefinitely, so unlocking
+			// it with a timeout would be confusing.
+			zeroKey(key.PrivateKey)
+			return nil
+		}
+		// Terminate the expire goroutine and replace it below.
+		close(u.abort)
+	}
+	if timeout > 0 {
+		u = &unlocked{Key: key, abort: make(chan struct{})}
+		go ks.expire(a.Address, u, timeout)
+	} else {
+		u = &unlocked{Key: key}
+	}
+	ks.unlocked[a.Address] = u
+	return nil
+}
+
+// Find resolves the given account into a unique entry in the keystore.
+func (ks *KeyStore) Find(a accounts.Account) (accounts.Account, error) {
+	ks.cache.maybeReload()
+	ks.cache.mu.Lock()
+	a, err := ks.cache.find(a)
+	ks.cache.mu.Unlock()
+	return a, err
+}
+
+func (ks *KeyStore) getDecryptedKey(a accounts.Account, auth string) (accounts.Account, *Key, error) {
+	a, err := ks.Find(a)
+	if err != nil {
+		return a, nil, err
+	}
+	key, err := ks.storage.GetKey(a.Address, a.URL.Path, auth)
+	return a, key, err
+}
+
+func (ks *KeyStore) expire(addr common.Address, u *unlocked, timeout time.Duration) {
+	t := time.NewTimer(timeout)
+	defer t.Stop()
+	select {
+	case <-u.abort:
+		// just quit
+	case <-t.C:
+		ks.mu.Lock()
+		// only drop if it's still the same key instance that dropLater
+		// was launched with. we can check that using pointer equality
+		// because the map stores a new pointer every time the key is
+		// unlocked.
+		if ks.unlocked[addr] == u {
+			zeroKey(u.PrivateKey)
+			delete(ks.unlocked, addr)
+		}
+		ks.mu.Unlock()
+	}
+}
+
+// NewAccount generates a new key and stores it into the key directory,
+// encrypting it with the passphrase.
+func (ks *KeyStore) NewAccount(passphrase string) (accounts.Account, error) {
+	_, account, err := storeNewKey(ks.storage, crand.Reader, passphrase)
+	if err != nil {
+		return accounts.Account{}, err
+	}
+	// Add the account to the cache immediately rather
+	// than waiting for file system notifications to pick it up.
+	ks.cache.add(account)
+	ks.refreshWallets()
+	return account, nil
+}
+
+// Export exports as a JSON key, encrypted with newPassphrase.
+func (ks *KeyStore) Export(a accounts.Account, passphrase, newPassphrase string) (keyJSON []byte, err error) {
+	_, key, err := ks.getDecryptedKey(a, passphrase)
+	if err != nil {
+		return nil, err
+	}
+	var N, P int
+	if store, ok := ks.storage.(*keyStorePassphrase); ok {
+		N, P = store.scryptN, store.scryptP
+	} else {
+		N, P = StandardScryptN, StandardScryptP
+	}
+	return EncryptKey(key, newPassphrase, N, P)
+}
+
+// Import stores the given encrypted JSON key into the key directory.
+func (ks *KeyStore) Import(keyJSON []byte, passphrase, newPassphrase string) (accounts.Account, error) {
+	key, err := DecryptKey(keyJSON, passphrase)
+	if key != nil && key.PrivateKey != nil {
+		defer zeroKey(key.PrivateKey)
+	}
+	if err != nil {
+		return accounts.Account{}, err
+	}
+	return ks.importKey(key, newPassphrase)
+}
+
+// ImportECDSA stores the given key into the key directory, encrypting it with the passphrase.
+func (ks *KeyStore) ImportECDSA(priv *ecdsa.PrivateKey, passphrase string) (accounts.Account, error) {
+	key := newKeyFromECDSA(priv)
+	if ks.cache.hasAddress(key.Address) {
+		return accounts.Account{}, fmt.Errorf("account already exists")
+	}
+	return ks.importKey(key, passphrase)
+}
+
+func (ks *KeyStore) importKey(key *Key, passphrase string) (accounts.Account, error) {
+	a := accounts.Account{Address: key.Address, URL: accounts.URL{Scheme: KeyStoreScheme, Path: ks.storage.JoinPath(keyFileName(key.Address))}}
+	if err := ks.storage.StoreKey(a.URL.Path, key, passphrase); err != nil {
+		return accounts.Account{}, err
+	}
+	ks.cache.add(a)
+	ks.refreshWallets()
+	return a, nil
+}
+
+// Update changes the passphrase of an existing account.
+func (ks *KeyStore) Update(a accounts.Account, passphrase, newPassphrase string) error {
+	a, key, err := ks.getDecryptedKey(a, passphrase)
+	if err != nil {
+		return err
+	}
+	return ks.storage.StoreKey(a.URL.Path, key, newPassphrase)
+}
+
+// ImportPreSaleKey decrypts the given Ethereum presale wallet and stores
+// a key file in the key directory. The key file is encrypted with the same passphrase.
+func (ks *KeyStore) ImportPreSaleKey(keyJSON []byte, passphrase string) (accounts.Account, error) {
+	a, _, err := importPreSaleKey(ks.storage, keyJSON, passphrase)
+	if err != nil {
+		return a, err
+	}
+	ks.cache.add(a)
+	ks.refreshWallets()
+	return a, nil
+}
+
+// zeroKey zeroes a private key in memory.
+func zeroKey(k *ecdsa.PrivateKey) {
+	b := k.D.Bits()
+	for i := range b {
+		b[i] = 0
+	}
+}
--- a/accounts/keystore/keystore_passphrase.go
+++ b/accounts/keystore/keystore_passphrase.go
@@ -0,0 +1,313 @@
+// Copyright 2014 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+/*
+
+This key store behaves as KeyStorePlain with the difference that
+the private key is encrypted and on disk uses another JSON encoding.
+
+The crypto is documented at https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition
+
+*/
+
+package keystore
+
+import (
+	"bytes"
+	"crypto/aes"
+	crand "crypto/rand"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"path/filepath"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/crypto/randentropy"
+	"github.com/pborman/uuid"
+	"golang.org/x/crypto/pbkdf2"
+	"golang.org/x/crypto/scrypt"
+)
+
+const (
+	keyHeaderKDF = "scrypt"
+
+	// StandardScryptN is the N parameter of Scrypt encryption algorithm, using 256MB
+	// memory and taking approximately 1s CPU time on a modern processor.
+	StandardScryptN = 1 << 18
+
+	// StandardScryptP is the P parameter of Scrypt encryption algorithm, using 256MB
+	// memory and taking approximately 1s CPU time on a modern processor.
+	StandardScryptP = 1
+
+	// LightScryptN is the N parameter of Scrypt encryption algorithm, using 4MB
+	// memory and taking approximately 100ms CPU time on a modern processor.
+	LightScryptN = 1 << 12
+
+	// LightScryptP is the P parameter of Scrypt encryption algorithm, using 4MB
+	// memory and taking approximately 100ms CPU time on a modern processor.
+	LightScryptP = 6
+
+	scryptR     = 8
+	scryptDKLen = 32
+)
+
+type keyStorePassphrase struct {
+	keysDirPath string
+	scryptN     int
+	scryptP     int
+}
+
+func (ks keyStorePassphrase) GetKey(addr common.Address, filename, auth string) (*Key, error) {
+	// Load the key from the keystore and decrypt its contents
+	keyjson, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+	key, err := DecryptKey(keyjson, auth)
+	if err != nil {
+		return nil, err
+	}
+	// Make sure we're really operating on the requested key (no swap attacks)
+	if key.Address != addr {
+		return nil, fmt.Errorf("key content mismatch: have account %x, want %x", key.Address, addr)
+	}
+	return key, nil
+}
+
+// StoreKey generates a key, encrypts with 'auth' and stores in the given directory
+func StoreKey(dir, auth string, scryptN, scryptP int) (common.Address, error) {
+	_, a, err := storeNewKey(&keyStorePassphrase{dir, scryptN, scryptP}, crand.Reader, auth)
+	return a.Address, err
+}
+
+func (ks keyStorePassphrase) StoreKey(filename string, key *Key, auth string) error {
+	keyjson, err := EncryptKey(key, auth, ks.scryptN, ks.scryptP)
+	if err != nil {
+		return err
+	}
+	return writeKeyFile(filename, keyjson)
+}
+
+func (ks keyStorePassphrase) JoinPath(filename string) string {
+	if filepath.IsAbs(filename) {
+		return filename
+	} else {
+		return filepath.Join(ks.keysDirPath, filename)
+	}
+}
+
+// EncryptKey encrypts a key using the specified scrypt parameters into a json
+// blob that can be decrypted later on.
+func EncryptKey(key *Key, auth string, scryptN, scryptP int) ([]byte, error) {
+	authArray := []byte(auth)
+	salt := randentropy.GetEntropyCSPRNG(32)
+	derivedKey, err := scrypt.Key(authArray, salt, scryptN, scryptR, scryptP, scryptDKLen)
+	if err != nil {
+		return nil, err
+	}
+	encryptKey := derivedKey[:16]
+	keyBytes := math.PaddedBigBytes(key.PrivateKey.D, 32)
+
+	iv := randentropy.GetEntropyCSPRNG(aes.BlockSize) // 16
+	cipherText, err := aesCTRXOR(encryptKey, keyBytes, iv)
+	if err != nil {
+		return nil, err
+	}
+	mac := crypto.Keccak256(derivedKey[16:32], cipherText)
+
+	scryptParamsJSON := make(map[string]interface{}, 5)
+	scryptParamsJSON["n"] = scryptN
+	scryptParamsJSON["r"] = scryptR
+	scryptParamsJSON["p"] = scryptP
+	scryptParamsJSON["dklen"] = scryptDKLen
+	scryptParamsJSON["salt"] = hex.EncodeToString(salt)
+
+	cipherParamsJSON := cipherparamsJSON{
+		IV: hex.EncodeToString(iv),
+	}
+
+	cryptoStruct := cryptoJSON{
+		Cipher:       "aes-128-ctr",
+		CipherText:   hex.EncodeToString(cipherText),
+		CipherParams: cipherParamsJSON,
+		KDF:          keyHeaderKDF,
+		KDFParams:    scryptParamsJSON,
+		MAC:          hex.EncodeToString(mac),
+	}
+	encryptedKeyJSONV3 := encryptedKeyJSONV3{
+		hex.EncodeToString(key.Address[:]),
+		cryptoStruct,
+		key.Id.String(),
+		version,
+	}
+	return json.Marshal(encryptedKeyJSONV3)
+}
+
+// DecryptKey decrypts a key from a json blob, returning the private key itself.
+func DecryptKey(keyjson []byte, auth string) (*Key, error) {
+	// Parse the json into a simple map to fetch the key version
+	m := make(map[string]interface{})
+	if err := json.Unmarshal(keyjson, &m); err != nil {
+		return nil, err
+	}
+	// Depending on the version try to parse one way or another
+	var (
+		keyBytes, keyId []byte
+		err             error
+	)
+	if version, ok := m["version"].(string); ok && version == "1" {
+		k := new(encryptedKeyJSONV1)
+		if err := json.Unmarshal(keyjson, k); err != nil {
+			return nil, err
+		}
+		keyBytes, keyId, err = decryptKeyV1(k, auth)
+	} else {
+		k := new(encryptedKeyJSONV3)
+		if err := json.Unmarshal(keyjson, k); err != nil {
+			return nil, err
+		}
+		keyBytes, keyId, err = decryptKeyV3(k, auth)
+	}
+	// Handle any decryption errors and return the key
+	if err != nil {
+		return nil, err
+	}
+	key := crypto.ToECDSAUnsafe(keyBytes)
+
+	return &Key{
+		Id:         uuid.UUID(keyId),
+		Address:    crypto.PubkeyToAddress(key.PublicKey),
+		PrivateKey: key,
+	}, nil
+}
+
+func decryptKeyV3(keyProtected *encryptedKeyJSONV3, auth string) (keyBytes []byte, keyId []byte, err error) {
+	if keyProtected.Version != version {
+		return nil, nil, fmt.Errorf("Version not supported: %v", keyProtected.Version)
+	}
+
+	if keyProtected.Crypto.Cipher != "aes-128-ctr" {
+		return nil, nil, fmt.Errorf("Cipher not supported: %v", keyProtected.Crypto.Cipher)
+	}
+
+	keyId = uuid.Parse(keyProtected.Id)
+	mac, err := hex.DecodeString(keyProtected.Crypto.MAC)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	iv, err := hex.DecodeString(keyProtected.Crypto.CipherParams.IV)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	cipherText, err := hex.DecodeString(keyProtected.Crypto.CipherText)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	derivedKey, err := getKDFKey(keyProtected.Crypto, auth)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	calculatedMAC := crypto.Keccak256(derivedKey[16:32], cipherText)
+	if !bytes.Equal(calculatedMAC, mac) {
+		return nil, nil, ErrDecrypt
+	}
+
+	plainText, err := aesCTRXOR(derivedKey[:16], cipherText, iv)
+	if err != nil {
+		return nil, nil, err
+	}
+	return plainText, keyId, err
+}
+
+func decryptKeyV1(keyProtected *encryptedKeyJSONV1, auth string) (keyBytes []byte, keyId []byte, err error) {
+	keyId = uuid.Parse(keyProtected.Id)
+	mac, err := hex.DecodeString(keyProtected.Crypto.MAC)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	iv, err := hex.DecodeString(keyProtected.Crypto.CipherParams.IV)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	cipherText, err := hex.DecodeString(keyProtected.Crypto.CipherText)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	derivedKey, err := getKDFKey(keyProtected.Crypto, auth)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	calculatedMAC := crypto.Keccak256(derivedKey[16:32], cipherText)
+	if !bytes.Equal(calculatedMAC, mac) {
+		return nil, nil, ErrDecrypt
+	}
+
+	plainText, err := aesCBCDecrypt(crypto.Keccak256(derivedKey[:16])[:16], cipherText, iv)
+	if err != nil {
+		return nil, nil, err
+	}
+	return plainText, keyId, err
+}
+
+func getKDFKey(cryptoJSON cryptoJSON, auth string) ([]byte, error) {
+	authArray := []byte(auth)
+	salt, err := hex.DecodeString(cryptoJSON.KDFParams["salt"].(string))
+	if err != nil {
+		return nil, err
+	}
+	dkLen := ensureInt(cryptoJSON.KDFParams["dklen"])
+
+	if cryptoJSON.KDF == keyHeaderKDF {
+		n := ensureInt(cryptoJSON.KDFParams["n"])
+		r := ensureInt(cryptoJSON.KDFParams["r"])
+		p := ensureInt(cryptoJSON.KDFParams["p"])
+		return scrypt.Key(authArray, salt, n, r, p, dkLen)
+
+	} else if cryptoJSON.KDF == "pbkdf2" {
+		c := ensureInt(cryptoJSON.KDFParams["c"])
+		prf := cryptoJSON.KDFParams["prf"].(string)
+		if prf != "hmac-sha256" {
+			return nil, fmt.Errorf("Unsupported PBKDF2 PRF: %s", prf)
+		}
+		key := pbkdf2.Key(authArray, salt, c, dkLen, sha256.New)
+		return key, nil
+	}
+
+	return nil, fmt.Errorf("Unsupported KDF: %s", cryptoJSON.KDF)
+}
+
+// TODO: can we do without this when unmarshalling dynamic JSON?
+// why do integers in KDF params end up as float64 and not int after
+// unmarshal?
+func ensureInt(x interface{}) int {
+	res, ok := x.(int)
+	if !ok {
+		res = int(x.(float64))
+	}
+	return res
+}
--- a/accounts/keystore/keystore_passphrase_test.go
+++ b/accounts/keystore/keystore_passphrase_test.go
@@ -0,0 +1,60 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package keystore
+
+import (
+	"io/ioutil"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+const (
+	veryLightScryptN = 2
+	veryLightScryptP = 1
+)
+
+// Tests that a json key file can be decrypted and encrypted in multiple rounds.
+func TestKeyEncryptDecrypt(t *testing.T) {
+	keyjson, err := ioutil.ReadFile("testdata/very-light-scrypt.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	password := ""
+	address := common.HexToAddress("45dea0fb0bba44f4fcf290bba71fd57d7117cbb8")
+
+	// Do a few rounds of decryption and encryption
+	for i := 0; i < 3; i++ {
+		// Try a bad password first
+		if _, err := DecryptKey(keyjson, password+"bad"); err == nil {
+			t.Errorf("test %d: json key decrypted with bad password", i)
+		}
+		// Decrypt with the correct password
+		key, err := DecryptKey(keyjson, password)
+		if err != nil {
+			t.Fatalf("test %d: json key failed to decrypt: %v", i, err)
+		}
+		if key.Address != address {
+			t.Errorf("test %d: key address mismatch: have %x, want %x", i, key.Address, address)
+		}
+		// Recrypt with a new password and start over
+		password += "new data appended"
+		if keyjson, err = EncryptKey(key, password, veryLightScryptN, veryLightScryptP); err != nil {
+			t.Errorf("test %d: failed to recrypt key %v", i, err)
+		}
+	}
+}
--- a/accounts/keystore/keystore_plain.go
+++ b/accounts/keystore/keystore_plain.go
@@ -0,0 +1,62 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package keystore
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+type keyStorePlain struct {
+	keysDirPath string
+}
+
+func (ks keyStorePlain) GetKey(addr common.Address, filename, auth string) (*Key, error) {
+	fd, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer fd.Close()
+	key := new(Key)
+	if err := json.NewDecoder(fd).Decode(key); err != nil {
+		return nil, err
+	}
+	if key.Address != addr {
+		return nil, fmt.Errorf("key content mismatch: have address %x, want %x", key.Address, addr)
+	}
+	return key, nil
+}
+
+func (ks keyStorePlain) StoreKey(filename string, key *Key, auth string) error {
+	content, err := json.Marshal(key)
+	if err != nil {
+		return err
+	}
+	return writeKeyFile(filename, content)
+}
+
+func (ks keyStorePlain) JoinPath(filename string) string {
+	if filepath.IsAbs(filename) {
+		return filename
+	} else {
+		return filepath.Join(ks.keysDirPath, filename)
+	}
+}
--- a/accounts/keystore/keystore_plain_test.go
+++ b/accounts/keystore/keystore_plain_test.go
@@ -0,0 +1,266 @@
+// Copyright 2014 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package keystore
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/crypto"
+)
+
+func tmpKeyStoreIface(t *testing.T, encrypted bool) (dir string, ks keyStore) {
+	d, err := ioutil.TempDir("", "geth-keystore-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if encrypted {
+		ks = &keyStorePassphrase{d, veryLightScryptN, veryLightScryptP}
+	} else {
+		ks = &keyStorePlain{d}
+	}
+	return d, ks
+}
+
+func TestKeyStorePlain(t *testing.T) {
+	dir, ks := tmpKeyStoreIface(t, false)
+	defer os.RemoveAll(dir)
+
+	pass := "" // not used but required by API
+	k1, account, err := storeNewKey(ks, rand.Reader, pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+	k2, err := ks.GetKey(k1.Address, account.URL.Path, pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(k1.Address, k2.Address) {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(k1.PrivateKey, k2.PrivateKey) {
+		t.Fatal(err)
+	}
+}
+
+func TestKeyStorePassphrase(t *testing.T) {
+	dir, ks := tmpKeyStoreIface(t, true)
+	defer os.RemoveAll(dir)
+
+	pass := "foo"
+	k1, account, err := storeNewKey(ks, rand.Reader, pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+	k2, err := ks.GetKey(k1.Address, account.URL.Path, pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(k1.Address, k2.Address) {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(k1.PrivateKey, k2.PrivateKey) {
+		t.Fatal(err)
+	}
+}
+
+func TestKeyStorePassphraseDecryptionFail(t *testing.T) {
+	dir, ks := tmpKeyStoreIface(t, true)
+	defer os.RemoveAll(dir)
+
+	pass := "foo"
+	k1, account, err := storeNewKey(ks, rand.Reader, pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err = ks.GetKey(k1.Address, account.URL.Path, "bar"); err != ErrDecrypt {
+		t.Fatalf("wrong error for invalid passphrase\ngot %q\nwant %q", err, ErrDecrypt)
+	}
+}
+
+func TestImportPreSaleKey(t *testing.T) {
+	dir, ks := tmpKeyStoreIface(t, true)
+	defer os.RemoveAll(dir)
+
+	// file content of a presale key file generated with:
+	// python pyethsaletool.py genwallet
+	// with password "foo"
+	fileContent := "{\"encseed\": \"26d87f5f2bf9835f9a47eefae571bc09f9107bb13d54ff12a4ec095d01f83897494cf34f7bed2ed34126ecba9db7b62de56c9d7cd136520a0427bfb11b8954ba7ac39b90d4650d3448e31185affcd74226a68f1e94b1108e6e0a4a91cdd83eba\", \"ethaddr\": \"d4584b5f6229b7be90727b0fc8c6b91bb427821f\", \"email\": \"gustav.simonsson@gmail.com\", \"btcaddr\": \"1EVknXyFC68kKNLkh6YnKzW41svSRoaAcx\"}"
+	pass := "foo"
+	account, _, err := importPreSaleKey(ks, []byte(fileContent), pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if account.Address != common.HexToAddress("d4584b5f6229b7be90727b0fc8c6b91bb427821f") {
+		t.Errorf("imported account has wrong address %x", account.Address)
+	}
+	if !strings.HasPrefix(account.URL.Path, dir) {
+		t.Errorf("imported account file not in keystore directory: %q", account.URL)
+	}
+}
+
+// Test and utils for the key store tests in the Ethereum JSON tests;
+// testdataKeyStoreTests/basic_tests.json
+type KeyStoreTestV3 struct {
+	Json     encryptedKeyJSONV3
+	Password string
+	Priv     string
+}
+
+type KeyStoreTestV1 struct {
+	Json     encryptedKeyJSONV1
+	Password string
+	Priv     string
+}
+
+func TestV3_PBKDF2_1(t *testing.T) {
+	t.Parallel()
+	tests := loadKeyStoreTestV3("testdata/v3_test_vector.json", t)
+	testDecryptV3(tests["wikipage_test_vector_pbkdf2"], t)
+}
+
+var testsSubmodule = filepath.Join("..", "..", "tests", "testdata", "KeyStoreTests")
+
+func skipIfSubmoduleMissing(t *testing.T) {
+	if !common.FileExist(testsSubmodule) {
+		t.Skipf("can't find JSON tests from submodule at %s", testsSubmodule)
+	}
+}
+
+func TestV3_PBKDF2_2(t *testing.T) {
+	skipIfSubmoduleMissing(t)
+	t.Parallel()
+	tests := loadKeyStoreTestV3(filepath.Join(testsSubmodule, "basic_tests.json"), t)
+	testDecryptV3(tests["test1"], t)
+}
+
+func TestV3_PBKDF2_3(t *testing.T) {
+	skipIfSubmoduleMissing(t)
+	t.Parallel()
+	tests := loadKeyStoreTestV3(filepath.Join(testsSubmodule, "basic_tests.json"), t)
+	testDecryptV3(tests["python_generated_test_with_odd_iv"], t)
+}
+
+func TestV3_PBKDF2_4(t *testing.T) {
+	skipIfSubmoduleMissing(t)
+	t.Parallel()
+	tests := loadKeyStoreTestV3(filepath.Join(testsSubmodule, "basic_tests.json"), t)
+	testDecryptV3(tests["evilnonce"], t)
+}
+
+func TestV3_Scrypt_1(t *testing.T) {
+	t.Parallel()
+	tests := loadKeyStoreTestV3("testdata/v3_test_vector.json", t)
+	testDecryptV3(tests["wikipage_test_vector_scrypt"], t)
+}
+
+func TestV3_Scrypt_2(t *testing.T) {
+	skipIfSubmoduleMissing(t)
+	t.Parallel()
+	tests := loadKeyStoreTestV3(filepath.Join(testsSubmodule, "basic_tests.json"), t)
+	testDecryptV3(tests["test2"], t)
+}
+
+func TestV1_1(t *testing.T) {
+	t.Parallel()
+	tests := loadKeyStoreTestV1("testdata/v1_test_vector.json", t)
+	testDecryptV1(tests["test1"], t)
+}
+
+func TestV1_2(t *testing.T) {
+	t.Parallel()
+	ks := &keyStorePassphrase{"testdata/v1", LightScryptN, LightScryptP}
+	addr := common.HexToAddress("cb61d5a9c4896fb9658090b597ef0e7be6f7b67e")
+	file := "testdata/v1/cb61d5a9c4896fb9658090b597ef0e7be6f7b67e/cb61d5a9c4896fb9658090b597ef0e7be6f7b67e"
+	k, err := ks.GetKey(addr, file, "g")
+	if err != nil {
+		t.Fatal(err)
+	}
+	privHex := hex.EncodeToString(crypto.FromECDSA(k.PrivateKey))
+	expectedHex := "d1b1178d3529626a1a93e073f65028370d14c7eb0936eb42abef05db6f37ad7d"
+	if privHex != expectedHex {
+		t.Fatal(fmt.Errorf("Unexpected privkey: %v, expected %v", privHex, expectedHex))
+	}
+}
+
+func testDecryptV3(test KeyStoreTestV3, t *testing.T) {
+	privBytes, _, err := decryptKeyV3(&test.Json, test.Password)
+	if err != nil {
+		t.Fatal(err)
+	}
+	privHex := hex.EncodeToString(privBytes)
+	if test.Priv != privHex {
+		t.Fatal(fmt.Errorf("Decrypted bytes not equal to test, expected %v have %v", test.Priv, privHex))
+	}
+}
+
+func testDecryptV1(test KeyStoreTestV1, t *testing.T) {
+	privBytes, _, err := decryptKeyV1(&test.Json, test.Password)
+	if err != nil {
+		t.Fatal(err)
+	}
+	privHex := hex.EncodeToString(privBytes)
+	if test.Priv != privHex {
+		t.Fatal(fmt.Errorf("Decrypted bytes not equal to test, expected %v have %v", test.Priv, privHex))
+	}
+}
+
+func loadKeyStoreTestV3(file string, t *testing.T) map[string]KeyStoreTestV3 {
+	tests := make(map[string]KeyStoreTestV3)
+	err := common.LoadJSON(file, &tests)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return tests
+}
+
+func loadKeyStoreTestV1(file string, t *testing.T) map[string]KeyStoreTestV1 {
+	tests := make(map[string]KeyStoreTestV1)
+	err := common.LoadJSON(file, &tests)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return tests
+}
+
+func TestKeyForDirectICAP(t *testing.T) {
+	t.Parallel()
+	key := NewKeyForDirectICAP(rand.Reader)
+	if !strings.HasPrefix(key.Address.Hex(), "0x00") {
+		t.Errorf("Expected first address byte to be zero, have: %s", key.Address.Hex())
+	}
+}
+
+func TestV3_31_Byte_Key(t *testing.T) {
+	t.Parallel()
+	tests := loadKeyStoreTestV3("testdata/v3_test_vector.json", t)
+	testDecryptV3(tests["31_byte_key"], t)
+}
+
+func TestV3_30_Byte_Key(t *testing.T) {
+	t.Parallel()
+	tests := loadKeyStoreTestV3("testdata/v3_test_vector.json", t)
+	testDecryptV3(tests["30_byte_key"], t)
+}
--- a/accounts/keystore/keystore_test.go
+++ b/accounts/keystore/keystore_test.go
@@ -0,0 +1,387 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package keystore
+
+import (
+	"io/ioutil"
+	"math/rand"
+	"os"
+	"runtime"
+	"sort"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/event"
+)
+
+var testSigData = make([]byte, 32)
+
+func TestKeyStore(t *testing.T) {
+	dir, ks := tmpKeyStore(t, true)
+	defer os.RemoveAll(dir)
+
+	a, err := ks.NewAccount("foo")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.HasPrefix(a.URL.Path, dir) {
+		t.Errorf("account file %s doesn't have dir prefix", a.URL)
+	}
+	stat, err := os.Stat(a.URL.Path)
+	if err != nil {
+		t.Fatalf("account file %s doesn't exist (%v)", a.URL, err)
+	}
+	if runtime.GOOS != "windows" && stat.Mode() != 0600 {
+		t.Fatalf("account file has wrong mode: got %o, want %o", stat.Mode(), 0600)
+	}
+	if !ks.HasAddress(a.Address) {
+		t.Errorf("HasAccount(%x) should've returned true", a.Address)
+	}
+	if err := ks.Update(a, "foo", "bar"); err != nil {
+		t.Errorf("Update error: %v", err)
+	}
+	if err := ks.Delete(a, "bar"); err != nil {
+		t.Errorf("Delete error: %v", err)
+	}
+	if common.FileExist(a.URL.Path) {
+		t.Errorf("account file %s should be gone after Delete", a.URL)
+	}
+	if ks.HasAddress(a.Address) {
+		t.Errorf("HasAccount(%x) should've returned true after Delete", a.Address)
+	}
+}
+
+func TestSign(t *testing.T) {
+	dir, ks := tmpKeyStore(t, true)
+	defer os.RemoveAll(dir)
+
+	pass := "" // not used but required by API
+	a1, err := ks.NewAccount(pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := ks.Unlock(a1, ""); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := ks.SignHash(accounts.Account{Address: a1.Address}, testSigData); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestSignWithPassphrase(t *testing.T) {
+	dir, ks := tmpKeyStore(t, true)
+	defer os.RemoveAll(dir)
+
+	pass := "passwd"
+	acc, err := ks.NewAccount(pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if _, unlocked := ks.unlocked[acc.Address]; unlocked {
+		t.Fatal("expected account to be locked")
+	}
+
+	_, err = ks.SignHashWithPassphrase(acc, pass, testSigData)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if _, unlocked := ks.unlocked[acc.Address]; unlocked {
+		t.Fatal("expected account to be locked")
+	}
+
+	if _, err = ks.SignHashWithPassphrase(acc, "invalid passwd", testSigData); err == nil {
+		t.Fatal("expected SignHashWithPassphrase to fail with invalid password")
+	}
+}
+
+func TestTimedUnlock(t *testing.T) {
+	dir, ks := tmpKeyStore(t, true)
+	defer os.RemoveAll(dir)
+
+	pass := "foo"
+	a1, err := ks.NewAccount(pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Signing without passphrase fails because account is locked
+	_, err = ks.SignHash(accounts.Account{Address: a1.Address}, testSigData)
+	if err != ErrLocked {
+		t.Fatal("Signing should've failed with ErrLocked before unlocking, got ", err)
+	}
+
+	// Signing with passphrase works
+	if err = ks.TimedUnlock(a1, pass, 100*time.Millisecond); err != nil {
+		t.Fatal(err)
+	}
+
+	// Signing without passphrase works because account is temp unlocked
+	_, err = ks.SignHash(accounts.Account{Address: a1.Address}, testSigData)
+	if err != nil {
+		t.Fatal("Signing shouldn't return an error after unlocking, got ", err)
+	}
+
+	// Signing fails again after automatic locking
+	time.Sleep(250 * time.Millisecond)
+	_, err = ks.SignHash(accounts.Account{Address: a1.Address}, testSigData)
+	if err != ErrLocked {
+		t.Fatal("Signing should've failed with ErrLocked timeout expired, got ", err)
+	}
+}
+
+func TestOverrideUnlock(t *testing.T) {
+	dir, ks := tmpKeyStore(t, false)
+	defer os.RemoveAll(dir)
+
+	pass := "foo"
+	a1, err := ks.NewAccount(pass)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Unlock indefinitely.
+	if err = ks.TimedUnlock(a1, pass, 5*time.Minute); err != nil {
+		t.Fatal(err)
+	}
+
+	// Signing without passphrase works because account is temp unlocked
+	_, err = ks.SignHash(accounts.Account{Address: a1.Address}, testSigData)
+	if err != nil {
+		t.Fatal("Signing shouldn't return an error after unlocking, got ", err)
+	}
+
+	// reset unlock to a shorter period, invalidates the previous unlock
+	if err = ks.TimedUnlock(a1, pass, 100*time.Millisecond); err != nil {
+		t.Fatal(err)
+	}
+
+	// Signing without passphrase still works because account is temp unlocked
+	_, err = ks.SignHash(accounts.Account{Address: a1.Address}, testSigData)
+	if err != nil {
+		t.Fatal("Signing shouldn't return an error after unlocking, got ", err)
+	}
+
+	// Signing fails again after automatic locking
+	time.Sleep(250 * time.Millisecond)
+	_, err = ks.SignHash(accounts.Account{Address: a1.Address}, testSigData)
+	if err != ErrLocked {
+		t.Fatal("Signing should've failed with ErrLocked timeout expired, got ", err)
+	}
+}
+
+// This test should fail under -race if signing races the expiration goroutine.
+func TestSignRace(t *testing.T) {
+	dir, ks := tmpKeyStore(t, false)
+	defer os.RemoveAll(dir)
+
+	// Create a test account.
+	a1, err := ks.NewAccount("")
+	if err != nil {
+		t.Fatal("could not create the test account", err)
+	}
+
+	if err := ks.TimedUnlock(a1, "", 15*time.Millisecond); err != nil {
+		t.Fatal("could not unlock the test account", err)
+	}
+	end := time.Now().Add(500 * time.Millisecond)
+	for time.Now().Before(end) {
+		if _, err := ks.SignHash(accounts.Account{Address: a1.Address}, testSigData); err == ErrLocked {
+			return
+		} else if err != nil {
+			t.Errorf("Sign error: %v", err)
+			return
+		}
+		time.Sleep(1 * time.Millisecond)
+	}
+	t.Errorf("Account did not lock within the timeout")
+}
+
+// Tests that the wallet notifier loop starts and stops correctly based on the
+// addition and removal of wallet event subscriptions.
+func TestWalletNotifierLifecycle(t *testing.T) {
+	// Create a temporary kesytore to test with
+	dir, ks := tmpKeyStore(t, false)
+	defer os.RemoveAll(dir)
+
+	// Ensure that the notification updater is not running yet
+	time.Sleep(250 * time.Millisecond)
+	ks.mu.RLock()
+	updating := ks.updating
+	ks.mu.RUnlock()
+
+	if updating {
+		t.Errorf("wallet notifier running without subscribers")
+	}
+	// Subscribe to the wallet feed and ensure the updater boots up
+	updates := make(chan accounts.WalletEvent)
+
+	subs := make([]event.Subscription, 2)
+	for i := 0; i < len(subs); i++ {
+		// Create a new subscription
+		subs[i] = ks.Subscribe(updates)
+
+		// Ensure the notifier comes online
+		time.Sleep(250 * time.Millisecond)
+		ks.mu.RLock()
+		updating = ks.updating
+		ks.mu.RUnlock()
+
+		if !updating {
+			t.Errorf("sub %d: wallet notifier not running after subscription", i)
+		}
+	}
+	// Unsubscribe and ensure the updater terminates eventually
+	for i := 0; i < len(subs); i++ {
+		// Close an existing subscription
+		subs[i].Unsubscribe()
+
+		// Ensure the notifier shuts down at and only at the last close
+		for k := 0; k < int(walletRefreshCycle/(250*time.Millisecond))+2; k++ {
+			ks.mu.RLock()
+			updating = ks.updating
+			ks.mu.RUnlock()
+
+			if i < len(subs)-1 && !updating {
+				t.Fatalf("sub %d: event notifier stopped prematurely", i)
+			}
+			if i == len(subs)-1 && !updating {
+				return
+			}
+			time.Sleep(250 * time.Millisecond)
+		}
+	}
+	t.Errorf("wallet notifier didn't terminate after unsubscribe")
+}
+
+type walletEvent struct {
+	accounts.WalletEvent
+	a accounts.Account
+}
+
+// Tests that wallet notifications and correctly fired when accounts are added
+// or deleted from the keystore.
+func TestWalletNotifications(t *testing.T) {
+	dir, ks := tmpKeyStore(t, false)
+	defer os.RemoveAll(dir)
+
+	// Subscribe to the wallet feed and collect events.
+	var (
+		events  []walletEvent
+		updates = make(chan accounts.WalletEvent)
+		sub     = ks.Subscribe(updates)
+	)
+	defer sub.Unsubscribe()
+	go func() {
+		for {
+			select {
+			case ev := <-updates:
+				events = append(events, walletEvent{ev, ev.Wallet.Accounts()[0]})
+			case <-sub.Err():
+				close(updates)
+				return
+			}
+		}
+	}()
+
+	// Randomly add and remove accounts.
+	var (
+		live       = make(map[common.Address]accounts.Account)
+		wantEvents []walletEvent
+	)
+	for i := 0; i < 1024; i++ {
+		if create := len(live) == 0 || rand.Int()%4 > 0; create {
+			// Add a new account and ensure wallet notifications arrives
+			account, err := ks.NewAccount("")
+			if err != nil {
+				t.Fatalf("failed to create test account: %v", err)
+			}
+			live[account.Address] = account
+			wantEvents = append(wantEvents, walletEvent{accounts.WalletEvent{Kind: accounts.WalletArrived}, account})
+		} else {
+			// Delete a random account.
+			var account accounts.Account
+			for _, a := range live {
+				account = a
+				break
+			}
+			if err := ks.Delete(account, ""); err != nil {
+				t.Fatalf("failed to delete test account: %v", err)
+			}
+			delete(live, account.Address)
+			wantEvents = append(wantEvents, walletEvent{accounts.WalletEvent{Kind: accounts.WalletDropped}, account})
+		}
+	}
+
+	// Shut down the event collector and check events.
+	sub.Unsubscribe()
+	<-updates
+	checkAccounts(t, live, ks.Wallets())
+	checkEvents(t, wantEvents, events)
+}
+
+// checkAccounts checks that all known live accounts are present in the wallet list.
+func checkAccounts(t *testing.T, live map[common.Address]accounts.Account, wallets []accounts.Wallet) {
+	if len(live) != len(wallets) {
+		t.Errorf("wallet list doesn't match required accounts: have %d, want %d", len(wallets), len(live))
+		return
+	}
+	liveList := make([]accounts.Account, 0, len(live))
+	for _, account := range live {
+		liveList = append(liveList, account)
+	}
+	sort.Sort(accountsByURL(liveList))
+	for j, wallet := range wallets {
+		if accs := wallet.Accounts(); len(accs) != 1 {
+			t.Errorf("wallet %d: contains invalid number of accounts: have %d, want 1", j, len(accs))
+		} else if accs[0] != liveList[j] {
+			t.Errorf("wallet %d: account mismatch: have %v, want %v", j, accs[0], liveList[j])
+		}
+	}
+}
+
+// checkEvents checks that all events in 'want' are present in 'have'. Events may be present multiple times.
+func checkEvents(t *testing.T, want []walletEvent, have []walletEvent) {
+	for _, wantEv := range want {
+		nmatch := 0
+		for ; len(have) > 0; nmatch++ {
+			if have[0].Kind != wantEv.Kind || have[0].a != wantEv.a {
+				break
+			}
+			have = have[1:]
+		}
+		if nmatch == 0 {
+			t.Fatalf("can't find event with Kind=%v for %x", wantEv.Kind, wantEv.a.Address)
+		}
+	}
+}
+
+func tmpKeyStore(t *testing.T, encrypted bool) (string, *KeyStore) {
+	d, err := ioutil.TempDir("", "eth-keystore-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	new := NewPlaintextKeyStore
+	if encrypted {
+		new = func(kd string) *KeyStore { return NewKeyStore(kd, veryLightScryptN, veryLightScryptP) }
+	}
+	return d, new(d)
+}
--- a/accounts/keystore/keystore_wallet.go
+++ b/accounts/keystore/keystore_wallet.go
@@ -0,0 +1,139 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package keystore
+
+import (
+	"math/big"
+
+	ethereum "github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/core/types"
+)
+
+// keystoreWallet implements the accounts.Wallet interface for the original
+// keystore.
+type keystoreWallet struct {
+	account  accounts.Account // Single account contained in this wallet
+	keystore *KeyStore        // Keystore where the account originates from
+}
+
+// URL implements accounts.Wallet, returning the URL of the account within.
+func (w *keystoreWallet) URL() accounts.URL {
+	return w.account.URL
+}
+
+// Status implements accounts.Wallet, returning whether the account held by the
+// keystore wallet is unlocked or not.
+func (w *keystoreWallet) Status() (string, error) {
+	w.keystore.mu.RLock()
+	defer w.keystore.mu.RUnlock()
+
+	if _, ok := w.keystore.unlocked[w.account.Address]; ok {
+		return "Unlocked", nil
+	}
+	return "Locked", nil
+}
+
+// Open implements accounts.Wallet, but is a noop for plain wallets since there
+// is no connection or decryption step necessary to access the list of accounts.
+func (w *keystoreWallet) Open(passphrase string) error { return nil }
+
+// Close implements accounts.Wallet, but is a noop for plain wallets since is no
+// meaningful open operation.
+func (w *keystoreWallet) Close() error { return nil }
+
+// Accounts implements accounts.Wallet, returning an account list consisting of
+// a single account that the plain kestore wallet contains.
+func (w *keystoreWallet) Accounts() []accounts.Account {
+	return []accounts.Account{w.account}
+}
+
+// Contains implements accounts.Wallet, returning whether a particular account is
+// or is not wrapped by this wallet instance.
+func (w *keystoreWallet) Contains(account accounts.Account) bool {
+	return account.Address == w.account.Address && (account.URL == (accounts.URL{}) || account.URL == w.account.URL)
+}
+
+// Derive implements accounts.Wallet, but is a noop for plain wallets since there
+// is no notion of hierarchical account derivation for plain keystore accounts.
+func (w *keystoreWallet) Derive(path accounts.DerivationPath, pin bool) (accounts.Account, error) {
+	return accounts.Account{}, accounts.ErrNotSupported
+}
+
+// SelfDerive implements accounts.Wallet, but is a noop for plain wallets since
+// there is no notion of hierarchical account derivation for plain keystore accounts.
+func (w *keystoreWallet) SelfDerive(base accounts.DerivationPath, chain ethereum.ChainStateReader) {}
+
+// SignHash implements accounts.Wallet, attempting to sign the given hash with
+// the given account. If the wallet does not wrap this particular account, an
+// error is returned to avoid account leakage (even though in theory we may be
+// able to sign via our shared keystore backend).
+func (w *keystoreWallet) SignHash(account accounts.Account, hash []byte) ([]byte, error) {
+	// Make sure the requested account is contained within
+	if account.Address != w.account.Address {
+		return nil, accounts.ErrUnknownAccount
+	}
+	if account.URL != (accounts.URL{}) && account.URL != w.account.URL {
+		return nil, accounts.ErrUnknownAccount
+	}
+	// Account seems valid, request the keystore to sign
+	return w.keystore.SignHash(account, hash)
+}
+
+// SignTx implements accounts.Wallet, attempting to sign the given transaction
+// with the given account. If the wallet does not wrap this particular account,
+// an error is returned to avoid account leakage (even though in theory we may
+// be able to sign via our shared keystore backend).
+func (w *keystoreWallet) SignTx(account accounts.Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
+	// Make sure the requested account is contained within
+	if account.Address != w.account.Address {
+		return nil, accounts.ErrUnknownAccount
+	}
+	if account.URL != (accounts.URL{}) && account.URL != w.account.URL {
+		return nil, accounts.ErrUnknownAccount
+	}
+	// Account seems valid, request the keystore to sign
+	return w.keystore.SignTx(account, tx, chainID)
+}
+
+// SignHashWithPassphrase implements accounts.Wallet, attempting to sign the
+// given hash with the given account using passphrase as extra authentication.
+func (w *keystoreWallet) SignHashWithPassphrase(account accounts.Account, passphrase string, hash []byte) ([]byte, error) {
+	// Make sure the requested account is contained within
+	if account.Address != w.account.Address {
+		return nil, accounts.ErrUnknownAccount
+	}
+	if account.URL != (accounts.URL{}) && account.URL != w.account.URL {
+		return nil, accounts.ErrUnknownAccount
+	}
+	// Account seems valid, request the keystore to sign
+	return w.keystore.SignHashWithPassphrase(account, passphrase, hash)
+}
+
+// SignTxWithPassphrase implements accounts.Wallet, attempting to sign the given
+// transaction with the given account using passphrase as extra authentication.
+func (w *keystoreWallet) SignTxWithPassphrase(account accounts.Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
+	// Make sure the requested account is contained within
+	if account.Address != w.account.Address {
+		return nil, accounts.ErrUnknownAccount
+	}
+	if account.URL != (accounts.URL{}) && account.URL != w.account.URL {
+		return nil, accounts.ErrUnknownAccount
+	}
+	// Account seems valid, request the keystore to sign
+	return w.keystore.SignTxWithPassphrase(account, passphrase, tx, chainID)
+}
--- a/accounts/keystore/presale.go
+++ b/accounts/keystore/presale.go
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

-package accounts
+package keystore

 import (
 	"crypto/aes"
@@ -22,22 +22,24 @@ import (
 	"crypto/sha256"
 	"encoding/hex"
 	"encoding/json"
+	"errors"
 	"fmt"

+	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/pborman/uuid"
 	"golang.org/x/crypto/pbkdf2"
 )

 // creates a Key and stores that in the given KeyStore by decrypting a presale key JSON
-func importPreSaleKey(keyStore keyStore, keyJSON []byte, password string) (Account, *Key, error) {
+func importPreSaleKey(keyStore keyStore, keyJSON []byte, password string) (accounts.Account, *Key, error) {
 	key, err := decryptPreSaleKey(keyJSON, password)
 	if err != nil {
-		return Account{}, nil, err
+		return accounts.Account{}, nil, err
 	}
 	key.Id = uuid.NewRandom()
-	a := Account{Address: key.Address, File: keyStore.JoinPath(keyFileName(key.Address))}
-	err = keyStore.StoreKey(a.File, key, password)
+	a := accounts.Account{Address: key.Address, URL: accounts.URL{Scheme: KeyStoreScheme, Path: keyStore.JoinPath(keyFileName(key.Address))}}
+	err = keyStore.StoreKey(a.URL.Path, key, password)
 	return a, key, err
 }

@@ -53,6 +55,12 @@ func decryptPreSaleKey(fileContent []byte, password string) (key *Key, err error
 		return nil, err
 	}
 	encSeedBytes, err := hex.DecodeString(preSaleKeyStruct.EncSeed)
+	if err != nil {
+		return nil, errors.New("invalid hex in encSeed")
+	}
+	if len(encSeedBytes) < 16 {
+		return nil, errors.New("invalid encSeed, too short")
+	}
 	iv := encSeedBytes[:16]
 	cipherText := encSeedBytes[16:]
 	/*
@@ -69,7 +77,8 @@ func decryptPreSaleKey(fileContent []byte, password string) (key *Key, err error
 		return nil, err
 	}
 	ethPriv := crypto.Keccak256(plainText)
-	ecKey := crypto.ToECDSA(ethPriv)
+	ecKey := crypto.ToECDSAUnsafe(ethPriv)
+
 	key = &Key{
 		Id:         nil,
 		Address:    crypto.PubkeyToAddress(ecKey.PublicKey),
--- a/accounts/keystore/testdata/dupes/1
+++ b/accounts/keystore/testdata/dupes/1
--- a/accounts/keystore/testdata/dupes/2
+++ b/accounts/keystore/testdata/dupes/2
--- a/accounts/keystore/testdata/dupes/foo
+++ b/accounts/keystore/testdata/dupes/foo
--- a/accounts/keystore/testdata/keystore/.hiddenfile
+++ b/accounts/keystore/testdata/keystore/.hiddenfile
--- a/accounts/keystore/testdata/keystore/README
+++ b/accounts/keystore/testdata/keystore/README
--- a/accounts/keystore/testdata/keystore/UTC--2016-03-22T12-57-55.920751759Z--7ef5a6135f1fd6a02593eedc869c6d41d934aef8
+++ b/accounts/keystore/testdata/keystore/UTC--2016-03-22T12-57-55.920751759Z--7ef5a6135f1fd6a02593eedc869c6d41d934aef8
--- a/accounts/keystore/testdata/keystore/aaa
+++ b/accounts/keystore/testdata/keystore/aaa
--- a/accounts/keystore/testdata/keystore/empty
+++ b/accounts/keystore/testdata/keystore/empty
--- a/accounts/keystore/testdata/keystore/foo/fd9bd350f08ee3c0c19b85a8e16114a11a60aa4e
+++ b/accounts/keystore/testdata/keystore/foo/fd9bd350f08ee3c0c19b85a8e16114a11a60aa4e
--- a/accounts/keystore/testdata/keystore/garbage
+++ b/accounts/keystore/testdata/keystore/garbage
--- a/accounts/keystore/testdata/keystore/no-address
+++ b/accounts/keystore/testdata/keystore/no-address
--- a/accounts/keystore/testdata/keystore/zero
+++ b/accounts/keystore/testdata/keystore/zero
--- a/accounts/keystore/testdata/keystore/zzz
+++ b/accounts/keystore/testdata/keystore/zzz
--- a/accounts/keystore/testdata/v1/cb61d5a9c4896fb9658090b597ef0e7be6f7b67e/cb61d5a9c4896fb9658090b597ef0e7be6f7b67e
+++ b/accounts/keystore/testdata/v1/cb61d5a9c4896fb9658090b597ef0e7be6f7b67e/cb61d5a9c4896fb9658090b597ef0e7be6f7b67e
--- a/accounts/keystore/testdata/v1_test_vector.json
+++ b/accounts/keystore/testdata/v1_test_vector.json
--- a/accounts/keystore/testdata/v3_test_vector.json
+++ b/accounts/keystore/testdata/v3_test_vector.json
--- a/accounts/keystore/testdata/very-light-scrypt.json
+++ b/accounts/keystore/testdata/very-light-scrypt.json
--- a/accounts/keystore/watch.go
+++ b/accounts/keystore/watch.go
@@ -0,0 +1,108 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// +build darwin,!ios freebsd linux,!arm64 netbsd solaris
+
+package keystore
+
+import (
+	"time"
+
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/rjeczalik/notify"
+)
+
+type watcher struct {
+	ac       *accountCache
+	starting bool
+	running  bool
+	ev       chan notify.EventInfo
+	quit     chan struct{}
+}
+
+func newWatcher(ac *accountCache) *watcher {
+	return &watcher{
+		ac:   ac,
+		ev:   make(chan notify.EventInfo, 10),
+		quit: make(chan struct{}),
+	}
+}
+
+// starts the watcher loop in the background.
+// Start a watcher in the background if that's not already in progress.
+// The caller must hold w.ac.mu.
+func (w *watcher) start() {
+	if w.starting || w.running {
+		return
+	}
+	w.starting = true
+	go w.loop()
+}
+
+func (w *watcher) close() {
+	close(w.quit)
+}
+
+func (w *watcher) loop() {
+	defer func() {
+		w.ac.mu.Lock()
+		w.running = false
+		w.starting = false
+		w.ac.mu.Unlock()
+	}()
+	logger := log.New("path", w.ac.keydir)
+
+	if err := notify.Watch(w.ac.keydir, w.ev, notify.All); err != nil {
+		logger.Trace("Failed to watch keystore folder", "err", err)
+		return
+	}
+	defer notify.Stop(w.ev)
+	logger.Trace("Started watching keystore folder")
+	defer logger.Trace("Stopped watching keystore folder")
+
+	w.ac.mu.Lock()
+	w.running = true
+	w.ac.mu.Unlock()
+
+	// Wait for file system events and reload.
+	// When an event occurs, the reload call is delayed a bit so that
+	// multiple events arriving quickly only cause a single reload.
+	var (
+		debounceDuration = 500 * time.Millisecond
+		rescanTriggered  = false
+		debounce         = time.NewTimer(0)
+	)
+	// Ignore initial trigger
+	if !debounce.Stop() {
+		<-debounce.C
+	}
+	defer debounce.Stop()
+	for {
+		select {
+		case <-w.quit:
+			return
+		case <-w.ev:
+			// Trigger the scan (with delay), if not already triggered
+			if !rescanTriggered {
+				debounce.Reset(debounceDuration)
+				rescanTriggered = true
+			}
+		case <-debounce.C:
+			w.ac.scanAccounts()
+			rescanTriggered = false
+		}
+	}
+}
--- a/accounts/keystore/watch_fallback.go
+++ b/accounts/keystore/watch_fallback.go
@@ -14,15 +14,15 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

-// +build ios linux,arm64 !darwin,!freebsd,!linux,!netbsd,!solaris,!windows
+// +build ios linux,arm64 windows !darwin,!freebsd,!linux,!netbsd,!solaris

 // This is the fallback implementation of directory watching.
 // It is used on unsupported platforms.

-package accounts
+package keystore

 type watcher struct{ running bool }

-func newWatcher(*addrCache) *watcher { return new(watcher) }
-func (*watcher) start()              {}
-func (*watcher) close()              {}
+func newWatcher(*accountCache) *watcher { return new(watcher) }
+func (*watcher) start()                 {}
+func (*watcher) close()                 {}
--- a/accounts/manager.go
+++ b/accounts/manager.go
@@ -0,0 +1,199 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package accounts
+
+import (
+	"reflect"
+	"sort"
+	"sync"
+
+	"github.com/ethereum/go-ethereum/event"
+)
+
+// Manager is an overarching account manager that can communicate with various
+// backends for signing transactions.
+type Manager struct {
+	backends map[reflect.Type][]Backend // Index of backends currently registered
+	updaters []event.Subscription       // Wallet update subscriptions for all backends
+	updates  chan WalletEvent           // Subscription sink for backend wallet changes
+	wallets  []Wallet                   // Cache of all wallets from all registered backends
+
+	feed event.Feed // Wallet feed notifying of arrivals/departures
+
+	quit chan chan error
+	lock sync.RWMutex
+}
+
+// NewManager creates a generic account manager to sign transaction via various
+// supported backends.
+func NewManager(backends ...Backend) *Manager {
+	// Retrieve the initial list of wallets from the backends and sort by URL
+	var wallets []Wallet
+	for _, backend := range backends {
+		wallets = merge(wallets, backend.Wallets()...)
+	}
+	// Subscribe to wallet notifications from all backends
+	updates := make(chan WalletEvent, 4*len(backends))
+
+	subs := make([]event.Subscription, len(backends))
+	for i, backend := range backends {
+		subs[i] = backend.Subscribe(updates)
+	}
+	// Assemble the account manager and return
+	am := &Manager{
+		backends: make(map[reflect.Type][]Backend),
+		updaters: subs,
+		updates:  updates,
+		wallets:  wallets,
+		quit:     make(chan chan error),
+	}
+	for _, backend := range backends {
+		kind := reflect.TypeOf(backend)
+		am.backends[kind] = append(am.backends[kind], backend)
+	}
+	go am.update()
+
+	return am
+}
+
+// Close terminates the account manager's internal notification processes.
+func (am *Manager) Close() error {
+	errc := make(chan error)
+	am.quit <- errc
+	return <-errc
+}
+
+// update is the wallet event loop listening for notifications from the backends
+// and updating the cache of wallets.
+func (am *Manager) update() {
+	// Close all subscriptions when the manager terminates
+	defer func() {
+		am.lock.Lock()
+		for _, sub := range am.updaters {
+			sub.Unsubscribe()
+		}
+		am.updaters = nil
+		am.lock.Unlock()
+	}()
+
+	// Loop until termination
+	for {
+		select {
+		case event := <-am.updates:
+			// Wallet event arrived, update local cache
+			am.lock.Lock()
+			switch event.Kind {
+			case WalletArrived:
+				am.wallets = merge(am.wallets, event.Wallet)
+			case WalletDropped:
+				am.wallets = drop(am.wallets, event.Wallet)
+			}
+			am.lock.Unlock()
+
+			// Notify any listeners of the event
+			am.feed.Send(event)
+
+		case errc := <-am.quit:
+			// Manager terminating, return
+			errc <- nil
+			return
+		}
+	}
+}
+
+// Backends retrieves the backend(s) with the given type from the account manager.
+func (am *Manager) Backends(kind reflect.Type) []Backend {
+	return am.backends[kind]
+}
+
+// Wallets returns all signer accounts registered under this account manager.
+func (am *Manager) Wallets() []Wallet {
+	am.lock.RLock()
+	defer am.lock.RUnlock()
+
+	cpy := make([]Wallet, len(am.wallets))
+	copy(cpy, am.wallets)
+	return cpy
+}
+
+// Wallet retrieves the wallet associated with a particular URL.
+func (am *Manager) Wallet(url string) (Wallet, error) {
+	am.lock.RLock()
+	defer am.lock.RUnlock()
+
+	parsed, err := parseURL(url)
+	if err != nil {
+		return nil, err
+	}
+	for _, wallet := range am.Wallets() {
+		if wallet.URL() == parsed {
+			return wallet, nil
+		}
+	}
+	return nil, ErrUnknownWallet
+}
+
+// Find attempts to locate the wallet corresponding to a specific account. Since
+// accounts can be dynamically added to and removed from wallets, this method has
+// a linear runtime in the number of wallets.
+func (am *Manager) Find(account Account) (Wallet, error) {
+	am.lock.RLock()
+	defer am.lock.RUnlock()
+
+	for _, wallet := range am.wallets {
+		if wallet.Contains(account) {
+			return wallet, nil
+		}
+	}
+	return nil, ErrUnknownAccount
+}
+
+// Subscribe creates an async subscription to receive notifications when the
+// manager detects the arrival or departure of a wallet from any of its backends.
+func (am *Manager) Subscribe(sink chan<- WalletEvent) event.Subscription {
+	return am.feed.Subscribe(sink)
+}
+
+// merge is a sorted analogue of append for wallets, where the ordering of the
+// origin list is preserved by inserting new wallets at the correct position.
+//
+// The original slice is assumed to be already sorted by URL.
+func merge(slice []Wallet, wallets ...Wallet) []Wallet {
+	for _, wallet := range wallets {
+		n := sort.Search(len(slice), func(i int) bool { return slice[i].URL().Cmp(wallet.URL()) >= 0 })
+		if n == len(slice) {
+			slice = append(slice, wallet)
+			continue
+		}
+		slice = append(slice[:n], append([]Wallet{wallet}, slice[n:]...)...)
+	}
+	return slice
+}
+
+// drop is the couterpart of merge, which looks up wallets from within the sorted
+// cache and removes the ones specified.
+func drop(slice []Wallet, wallets ...Wallet) []Wallet {
+	for _, wallet := range wallets {
+		n := sort.Search(len(slice), func(i int) bool { return slice[i].URL().Cmp(wallet.URL()) >= 0 })
+		if n == len(slice) {
+			// Wallet not found, may happen during startup
+			continue
+		}
+		slice = append(slice[:n], slice[n+1:]...)
+	}
+	return slice
+}
--- a/accounts/url.go
+++ b/accounts/url.go
@@ -0,0 +1,88 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package accounts
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+)
+
+// URL represents the canonical identification URL of a wallet or account.
+//
+// It is a simplified version of url.URL, with the important limitations (which
+// are considered features here) that it contains value-copyable components only,
+// as well as that it doesn't do any URL encoding/decoding of special characters.
+//
+// The former is important to allow an account to be copied without leaving live
+// references to the original version, whereas the latter is important to ensure
+// one single canonical form opposed to many allowed ones by the RFC 3986 spec.
+//
+// As such, these URLs should not be used outside of the scope of an Ethereum
+// wallet or account.
+type URL struct {
+	Scheme string // Protocol scheme to identify a capable account backend
+	Path   string // Path for the backend to identify a unique entity
+}
+
+// parseURL converts a user supplied URL into the accounts specific structure.
+func parseURL(url string) (URL, error) {
+	parts := strings.Split(url, "://")
+	if len(parts) != 2 || parts[0] == "" {
+		return URL{}, errors.New("protocol scheme missing")
+	}
+	return URL{
+		Scheme: parts[0],
+		Path:   parts[1],
+	}, nil
+}
+
+// String implements the stringer interface.
+func (u URL) String() string {
+	if u.Scheme != "" {
+		return fmt.Sprintf("%s://%s", u.Scheme, u.Path)
+	}
+	return u.Path
+}
+
+// TerminalString implements the log.TerminalStringer interface.
+func (u URL) TerminalString() string {
+	url := u.String()
+	if len(url) > 32 {
+		return url[:31] + "…"
+	}
+	return url
+}
+
+// MarshalJSON implements the json.Marshaller interface.
+func (u URL) MarshalJSON() ([]byte, error) {
+	return json.Marshal(u.String())
+}
+
+// Cmp compares x and y and returns:
+//
+//   -1 if x <  y
+//    0 if x == y
+//   +1 if x >  y
+//
+func (u URL) Cmp(url URL) int {
+	if u.Scheme == url.Scheme {
+		return strings.Compare(u.Path, url.Path)
+	}
+	return strings.Compare(u.Scheme, url.Scheme)
+}
--- a/accounts/usbwallet/hub.go
+++ b/accounts/usbwallet/hub.go
@@ -0,0 +1,238 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package usbwallet
+
+import (
+	"errors"
+	"runtime"
+	"sync"
+	"time"
+
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/karalabe/hid"
+)
+
+// LedgerScheme is the protocol scheme prefixing account and wallet URLs.
+const LedgerScheme = "ledger"
+
+// TrezorScheme is the protocol scheme prefixing account and wallet URLs.
+const TrezorScheme = "trezor"
+
+// refreshCycle is the maximum time between wallet refreshes (if USB hotplug
+// notifications don't work).
+const refreshCycle = time.Second
+
+// refreshThrottling is the minimum time between wallet refreshes to avoid USB
+// trashing.
+const refreshThrottling = 500 * time.Millisecond
+
+// Hub is a accounts.Backend that can find and handle generic USB hardware wallets.
+type Hub struct {
+	scheme     string                  // Protocol scheme prefixing account and wallet URLs.
+	vendorID   uint16                  // USB vendor identifier used for device discovery
+	productIDs []uint16                // USB product identifiers used for device discovery
+	usageID    uint16                  // USB usage page identifier used for macOS device discovery
+	endpointID int                     // USB endpoint identifier used for non-macOS device discovery
+	makeDriver func(log.Logger) driver // Factory method to construct a vendor specific driver
+
+	refreshed   time.Time               // Time instance when the list of wallets was last refreshed
+	wallets     []accounts.Wallet       // List of USB wallet devices currently tracking
+	updateFeed  event.Feed              // Event feed to notify wallet additions/removals
+	updateScope event.SubscriptionScope // Subscription scope tracking current live listeners
+	updating    bool                    // Whether the event notification loop is running
+
+	quit chan chan error
+
+	stateLock sync.RWMutex // Protects the internals of the hub from racey access
+
+	// TODO(karalabe): remove if hotplug lands on Windows
+	commsPend int        // Number of operations blocking enumeration
+	commsLock sync.Mutex // Lock protecting the pending counter and enumeration
+}
+
+// NewLedgerHub creates a new hardware wallet manager for Ledger devices.
+func NewLedgerHub() (*Hub, error) {
+	return newHub(LedgerScheme, 0x2c97, []uint16{0x0000 /* Ledger Blue */, 0x0001 /* Ledger Nano S */}, 0xffa0, 0, newLedgerDriver)
+}
+
+// NewTrezorHub creates a new hardware wallet manager for Trezor devices.
+func NewTrezorHub() (*Hub, error) {
+	return newHub(TrezorScheme, 0x534c, []uint16{0x0001 /* Trezor 1 */}, 0xff00, 0, newTrezorDriver)
+}
+
+// newHub creates a new hardware wallet manager for generic USB devices.
+func newHub(scheme string, vendorID uint16, productIDs []uint16, usageID uint16, endpointID int, makeDriver func(log.Logger) driver) (*Hub, error) {
+	if !hid.Supported() {
+		return nil, errors.New("unsupported platform")
+	}
+	hub := &Hub{
+		scheme:     scheme,
+		vendorID:   vendorID,
+		productIDs: productIDs,
+		usageID:    usageID,
+		endpointID: endpointID,
+		makeDriver: makeDriver,
+		quit:       make(chan chan error),
+	}
+	hub.refreshWallets()
+	return hub, nil
+}
+
+// Wallets implements accounts.Backend, returning all the currently tracked USB
+// devices that appear to be hardware wallets.
+func (hub *Hub) Wallets() []accounts.Wallet {
+	// Make sure the list of wallets is up to date
+	hub.refreshWallets()
+
+	hub.stateLock.RLock()
+	defer hub.stateLock.RUnlock()
+
+	cpy := make([]accounts.Wallet, len(hub.wallets))
+	copy(cpy, hub.wallets)
+	return cpy
+}
+
+// refreshWallets scans the USB devices attached to the machine and updates the
+// list of wallets based on the found devices.
+func (hub *Hub) refreshWallets() {
+	// Don't scan the USB like crazy it the user fetches wallets in a loop
+	hub.stateLock.RLock()
+	elapsed := time.Since(hub.refreshed)
+	hub.stateLock.RUnlock()
+
+	if elapsed < refreshThrottling {
+		return
+	}
+	// Retrieve the current list of USB wallet devices
+	var devices []hid.DeviceInfo
+
+	if runtime.GOOS == "linux" {
+		// hidapi on Linux opens the device during enumeration to retrieve some infos,
+		// breaking the Ledger protocol if that is waiting for user confirmation. This
+		// is a bug acknowledged at Ledger, but it won't be fixed on old devices so we
+		// need to prevent concurrent comms ourselves. The more elegant solution would
+		// be to ditch enumeration in favor of hutplug events, but that don't work yet
+		// on Windows so if we need to hack it anyway, this is more elegant for now.
+		hub.commsLock.Lock()
+		if hub.commsPend > 0 { // A confirmation is pending, don't refresh
+			hub.commsLock.Unlock()
+			return
+		}
+	}
+	for _, info := range hid.Enumerate(hub.vendorID, 0) {
+		for _, id := range hub.productIDs {
+			if info.ProductID == id && (info.UsagePage == hub.usageID || info.Interface == hub.endpointID) {
+				devices = append(devices, info)
+				break
+			}
+		}
+	}
+	if runtime.GOOS == "linux" {
+		// See rationale before the enumeration why this is needed and only on Linux.
+		hub.commsLock.Unlock()
+	}
+	// Transform the current list of wallets into the new one
+	hub.stateLock.Lock()
+
+	wallets := make([]accounts.Wallet, 0, len(devices))
+	events := []accounts.WalletEvent{}
+
+	for _, device := range devices {
+		url := accounts.URL{Scheme: hub.scheme, Path: device.Path}
+
+		// Drop wallets in front of the next device or those that failed for some reason
+		for len(hub.wallets) > 0 {
+			// Abort if we're past the current device and found an operational one
+			_, failure := hub.wallets[0].Status()
+			if hub.wallets[0].URL().Cmp(url) >= 0 || failure == nil {
+				break
+			}
+			// Drop the stale and failed devices
+			events = append(events, accounts.WalletEvent{Wallet: hub.wallets[0], Kind: accounts.WalletDropped})
+			hub.wallets = hub.wallets[1:]
+		}
+		// If there are no more wallets or the device is before the next, wrap new wallet
+		if len(hub.wallets) == 0 || hub.wallets[0].URL().Cmp(url) > 0 {
+			logger := log.New("url", url)
+			wallet := &wallet{hub: hub, driver: hub.makeDriver(logger), url: &url, info: device, log: logger}
+
+			events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletArrived})
+			wallets = append(wallets, wallet)
+			continue
+		}
+		// If the device is the same as the first wallet, keep it
+		if hub.wallets[0].URL().Cmp(url) == 0 {
+			wallets = append(wallets, hub.wallets[0])
+			hub.wallets = hub.wallets[1:]
+			continue
+		}
+	}
+	// Drop any leftover wallets and set the new batch
+	for _, wallet := range hub.wallets {
+		events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletDropped})
+	}
+	hub.refreshed = time.Now()
+	hub.wallets = wallets
+	hub.stateLock.Unlock()
+
+	// Fire all wallet events and return
+	for _, event := range events {
+		hub.updateFeed.Send(event)
+	}
+}
+
+// Subscribe implements accounts.Backend, creating an async subscription to
+// receive notifications on the addition or removal of USB wallets.
+func (hub *Hub) Subscribe(sink chan<- accounts.WalletEvent) event.Subscription {
+	// We need the mutex to reliably start/stop the update loop
+	hub.stateLock.Lock()
+	defer hub.stateLock.Unlock()
+
+	// Subscribe the caller and track the subscriber count
+	sub := hub.updateScope.Track(hub.updateFeed.Subscribe(sink))
+
+	// Subscribers require an active notification loop, start it
+	if !hub.updating {
+		hub.updating = true
+		go hub.updater()
+	}
+	return sub
+}
+
+// updater is responsible for maintaining an up-to-date list of wallets managed
+// by the USB hub, and for firing wallet addition/removal events.
+func (hub *Hub) updater() {
+	for {
+		// TODO: Wait for a USB hotplug event (not supported yet) or a refresh timeout
+		// <-hub.changes
+		time.Sleep(refreshCycle)
+
+		// Run the wallet refresher
+		hub.refreshWallets()
+
+		// If all our subscribers left, stop the updater
+		hub.stateLock.Lock()
+		if hub.updateScope.Count() == 0 {
+			hub.updating = false
+			hub.stateLock.Unlock()
+			return
+		}
+		hub.stateLock.Unlock()
+	}
+}
--- a/accounts/usbwallet/internal/trezor/messages.pb.go
+++ b/accounts/usbwallet/internal/trezor/messages.pb.go
--- a/accounts/usbwallet/internal/trezor/messages.proto
+++ b/accounts/usbwallet/internal/trezor/messages.proto
@@ -0,0 +1,905 @@
+// This file originates from the SatoshiLabs Trezor `common` repository at:
+//   https://github.com/trezor/trezor-common/blob/master/protob/messages.proto
+// dated 28.07.2017, commit dd8ec3231fb5f7992360aff9bdfe30bb58130f4b.
+
+syntax = "proto2";
+
+/**
+ * Messages for TREZOR communication
+ */
+
+// Sugar for easier handling in Java
+option java_package = "com.satoshilabs.trezor.lib.protobuf";
+option java_outer_classname = "TrezorMessage";
+
+import "types.proto";
+
+/**
+ * Mapping between Trezor wire identifier (uint) and a protobuf message
+ */
+enum MessageType {
+	MessageType_Initialize = 0 [(wire_in) = true];
+	MessageType_Ping = 1 [(wire_in) = true];
+	MessageType_Success = 2 [(wire_out) = true];
+	MessageType_Failure = 3 [(wire_out) = true];
+	MessageType_ChangePin = 4 [(wire_in) = true];
+	MessageType_WipeDevice = 5 [(wire_in) = true];
+	MessageType_FirmwareErase = 6 [(wire_in) = true, (wire_bootloader) = true];
+	MessageType_FirmwareUpload = 7 [(wire_in) = true, (wire_bootloader) = true];
+	MessageType_FirmwareRequest = 8 [(wire_out) = true, (wire_bootloader) = true];
+	MessageType_GetEntropy = 9 [(wire_in) = true];
+	MessageType_Entropy = 10 [(wire_out) = true];
+	MessageType_GetPublicKey = 11 [(wire_in) = true];
+	MessageType_PublicKey = 12 [(wire_out) = true];
+	MessageType_LoadDevice = 13 [(wire_in) = true];
+	MessageType_ResetDevice = 14 [(wire_in) = true];
+	MessageType_SignTx = 15 [(wire_in) = true];
+	MessageType_SimpleSignTx = 16 [(wire_in) = true, deprecated = true];
+	MessageType_Features = 17 [(wire_out) = true];
+	MessageType_PinMatrixRequest = 18 [(wire_out) = true];
+	MessageType_PinMatrixAck = 19 [(wire_in) = true, (wire_tiny) = true];
+	MessageType_Cancel = 20 [(wire_in) = true];
+	MessageType_TxRequest = 21 [(wire_out) = true];
+	MessageType_TxAck = 22 [(wire_in) = true];
+	MessageType_CipherKeyValue = 23 [(wire_in) = true];
+	MessageType_ClearSession = 24 [(wire_in) = true];
+	MessageType_ApplySettings = 25 [(wire_in) = true];
+	MessageType_ButtonRequest = 26 [(wire_out) = true];
+	MessageType_ButtonAck = 27 [(wire_in) = true, (wire_tiny) = true];
+	MessageType_ApplyFlags = 28 [(wire_in) = true];
+	MessageType_GetAddress = 29 [(wire_in) = true];
+	MessageType_Address = 30 [(wire_out) = true];
+	MessageType_SelfTest = 32 [(wire_in) = true, (wire_bootloader) = true];
+	MessageType_BackupDevice = 34 [(wire_in) = true];
+	MessageType_EntropyRequest = 35 [(wire_out) = true];
+	MessageType_EntropyAck = 36 [(wire_in) = true];
+	MessageType_SignMessage = 38 [(wire_in) = true];
+	MessageType_VerifyMessage = 39 [(wire_in) = true];
+	MessageType_MessageSignature = 40 [(wire_out) = true];
+	MessageType_PassphraseRequest = 41 [(wire_out) = true];
+	MessageType_PassphraseAck = 42 [(wire_in) = true, (wire_tiny) = true];
+	MessageType_EstimateTxSize = 43 [(wire_in) = true, deprecated = true];
+	MessageType_TxSize = 44 [(wire_out) = true, deprecated = true];
+	MessageType_RecoveryDevice = 45 [(wire_in) = true];
+	MessageType_WordRequest = 46 [(wire_out) = true];
+	MessageType_WordAck = 47 [(wire_in) = true];
+	MessageType_CipheredKeyValue = 48 [(wire_out) = true];
+	MessageType_EncryptMessage = 49 [(wire_in) = true, deprecated = true];
+	MessageType_EncryptedMessage = 50 [(wire_out) = true, deprecated = true];
+	MessageType_DecryptMessage = 51 [(wire_in) = true, deprecated = true];
+	MessageType_DecryptedMessage = 52 [(wire_out) = true, deprecated = true];
+	MessageType_SignIdentity = 53 [(wire_in) = true];
+	MessageType_SignedIdentity = 54 [(wire_out) = true];
+	MessageType_GetFeatures = 55 [(wire_in) = true];
+	MessageType_EthereumGetAddress = 56 [(wire_in) = true];
+	MessageType_EthereumAddress = 57 [(wire_out) = true];
+	MessageType_EthereumSignTx = 58 [(wire_in) = true];
+	MessageType_EthereumTxRequest = 59 [(wire_out) = true];
+	MessageType_EthereumTxAck = 60 [(wire_in) = true];
+	MessageType_GetECDHSessionKey = 61 [(wire_in) = true];
+	MessageType_ECDHSessionKey = 62 [(wire_out) = true];
+	MessageType_SetU2FCounter = 63 [(wire_in) = true];
+	MessageType_EthereumSignMessage = 64 [(wire_in) = true];
+	MessageType_EthereumVerifyMessage = 65 [(wire_in) = true];
+	MessageType_EthereumMessageSignature = 66 [(wire_out) = true];
+	MessageType_DebugLinkDecision = 100 [(wire_debug_in) = true, (wire_tiny) = true];
+	MessageType_DebugLinkGetState = 101 [(wire_debug_in) = true];
+	MessageType_DebugLinkState = 102 [(wire_debug_out) = true];
+	MessageType_DebugLinkStop = 103 [(wire_debug_in) = true];
+	MessageType_DebugLinkLog = 104 [(wire_debug_out) = true];
+	MessageType_DebugLinkMemoryRead = 110 [(wire_debug_in) = true];
+	MessageType_DebugLinkMemory = 111 [(wire_debug_out) = true];
+	MessageType_DebugLinkMemoryWrite = 112 [(wire_debug_in) = true];
+	MessageType_DebugLinkFlashErase = 113 [(wire_debug_in) = true];
+}
+
+////////////////////
+// Basic messages //
+////////////////////
+
+/**
+ * Request: Reset device to default state and ask for device details
+ * @next Features
+ */
+message Initialize {
+}
+
+/**
+ * Request: Ask for device details (no device reset)
+ * @next Features
+ */
+message GetFeatures {
+}
+
+/**
+ * Response: Reports various information about the device
+ * @prev Initialize
+ * @prev GetFeatures
+ */
+message Features {
+	optional string vendor = 1;			// name of the manufacturer, e.g. "bitcointrezor.com"
+	optional uint32 major_version = 2;		// major version of the device, e.g. 1
+	optional uint32 minor_version = 3;		// minor version of the device, e.g. 0
+	optional uint32 patch_version = 4;		// patch version of the device, e.g. 0
+	optional bool bootloader_mode = 5;		// is device in bootloader mode?
+	optional string device_id = 6;			// device's unique identifier
+	optional bool pin_protection = 7;		// is device protected by PIN?
+	optional bool passphrase_protection = 8;	// is node/mnemonic encrypted using passphrase?
+	optional string language = 9;			// device language
+	optional string label = 10;			// device description label
+	repeated CoinType coins = 11;			// supported coins
+	optional bool initialized = 12;			// does device contain seed?
+	optional bytes revision = 13;			// SCM revision of firmware
+	optional bytes bootloader_hash = 14;		// hash of the bootloader
+	optional bool imported = 15;			// was storage imported from an external source?
+	optional bool pin_cached = 16;			// is PIN already cached in session?
+	optional bool passphrase_cached = 17;		// is passphrase already cached in session?
+	optional bool firmware_present = 18;		// is valid firmware loaded?
+	optional bool needs_backup = 19;		// does storage need backup? (equals to Storage.needs_backup)
+	optional uint32 flags = 20;			// device flags (equals to Storage.flags)
+}
+
+/**
+ * Request: clear session (removes cached PIN, passphrase, etc).
+ * @next Success
+ */
+message ClearSession {
+}
+
+/**
+ * Request: change language and/or label of the device
+ * @next Success
+ * @next Failure
+ * @next ButtonRequest
+ * @next PinMatrixRequest
+ */
+message ApplySettings {
+	optional string language = 1;
+	optional string label = 2;
+	optional bool use_passphrase = 3;
+	optional bytes homescreen = 4;
+}
+
+/**
+ * Request: set flags of the device
+ * @next Success
+ * @next Failure
+ */
+message ApplyFlags {
+	optional uint32 flags = 1;	// bitmask, can only set bits, not unset
+}
+
+/**
+ * Request: Starts workflow for setting/changing/removing the PIN
+ * @next ButtonRequest
+ * @next PinMatrixRequest
+ */
+message ChangePin {
+	optional bool remove = 1;	// is PIN removal requested?
+}
+
+/**
+ * Request: Test if the device is alive, device sends back the message in Success response
+ * @next Success
+ */
+message Ping {
+	optional string message = 1;			// message to send back in Success message
+	optional bool button_protection = 2;		// ask for button press
+	optional bool pin_protection = 3;		// ask for PIN if set in device
+	optional bool passphrase_protection = 4;	// ask for passphrase if set in device
+}
+
+/**
+ * Response: Success of the previous request
+ */
+message Success {
+	optional string message = 1;	// human readable description of action or request-specific payload
+}
+
+/**
+ * Response: Failure of the previous request
+ */
+message Failure {
+	optional FailureType code = 1;	// computer-readable definition of the error state
+	optional string message = 2;	// human-readable message of the error state
+}
+
+/**
+ * Response: Device is waiting for HW button press.
+ * @next ButtonAck
+ * @next Cancel
+ */
+message ButtonRequest {
+	optional ButtonRequestType code = 1;
+	optional string data = 2;
+}
+
+/**
+ * Request: Computer agrees to wait for HW button press
+ * @prev ButtonRequest
+ */
+message ButtonAck {
+}
+
+/**
+ * Response: Device is asking computer to show PIN matrix and awaits PIN encoded using this matrix scheme
+ * @next PinMatrixAck
+ * @next Cancel
+ */
+message PinMatrixRequest {
+	optional PinMatrixRequestType type = 1;
+}
+
+/**
+ * Request: Computer responds with encoded PIN
+ * @prev PinMatrixRequest
+ */
+message PinMatrixAck {
+	required string pin = 1;		// matrix encoded PIN entered by user
+}
+
+/**
+ * Request: Abort last operation that required user interaction
+ * @prev ButtonRequest
+ * @prev PinMatrixRequest
+ * @prev PassphraseRequest
+ */
+message Cancel {
+}
+
+/**
+ * Response: Device awaits encryption passphrase
+ * @next PassphraseAck
+ * @next Cancel
+ */
+message PassphraseRequest {
+}
+
+/**
+ * Request: Send passphrase back
+ * @prev PassphraseRequest
+ */
+message PassphraseAck {
+	required string passphrase = 1;
+}
+
+/**
+ * Request: Request a sample of random data generated by hardware RNG. May be used for testing.
+ * @next ButtonRequest
+ * @next Entropy
+ * @next Failure
+ */
+message GetEntropy {
+	required uint32 size = 1;		// size of requested entropy
+}
+
+/**
+ * Response: Reply with random data generated by internal RNG
+ * @prev GetEntropy
+ */
+message Entropy {
+	required bytes entropy = 1;		// stream of random generated bytes
+}
+
+/**
+ * Request: Ask device for public key corresponding to address_n path
+ * @next PassphraseRequest
+ * @next PublicKey
+ * @next Failure
+ */
+message GetPublicKey {
+	repeated uint32 address_n = 1;		// BIP-32 path to derive the key from master node
+	optional string ecdsa_curve_name = 2;	// ECDSA curve name to use
+	optional bool show_display = 3;		// optionally show on display before sending the result
+	optional string coin_name = 4 [default='Bitcoin'];
+}
+
+/**
+ * Response: Contains public key derived from device private seed
+ * @prev GetPublicKey
+ */
+message PublicKey {
+	required HDNodeType node = 1;		// BIP32 public node
+	optional string xpub = 2;		// serialized form of public node
+}
+
+/**
+ * Request: Ask device for address corresponding to address_n path
+ * @next PassphraseRequest
+ * @next Address
+ * @next Failure
+ */
+message GetAddress {
+	repeated uint32 address_n = 1;						// BIP-32 path to derive the key from master node
+	optional string coin_name = 2 [default='Bitcoin'];
+	optional bool show_display = 3			;			// optionally show on display before sending the result
+	optional MultisigRedeemScriptType multisig = 4;				// filled if we are showing a multisig address
+	optional InputScriptType script_type = 5 [default=SPENDADDRESS];	// used to distinguish between various address formats (non-segwit, segwit, etc.)
+}
+
+/**
+ * Request: Ask device for Ethereum address corresponding to address_n path
+ * @next PassphraseRequest
+ * @next EthereumAddress
+ * @next Failure
+ */
+message EthereumGetAddress {
+	repeated uint32 address_n = 1;			// BIP-32 path to derive the key from master node
+	optional bool show_display = 2;			// optionally show on display before sending the result
+}
+
+/**
+ * Response: Contains address derived from device private seed
+ * @prev GetAddress
+ */
+message Address {
+	required string address = 1;		// Coin address in Base58 encoding
+}
+
+/**
+ * Response: Contains an Ethereum address derived from device private seed
+ * @prev EthereumGetAddress
+ */
+message EthereumAddress {
+	required bytes address = 1;		// Coin address as an Ethereum 160 bit hash
+}
+
+/**
+ * Request: Request device to wipe all sensitive data and settings
+ * @next ButtonRequest
+ */
+message WipeDevice {
+}
+
+/**
+ * Request: Load seed and related internal settings from the computer
+ * @next ButtonRequest
+ * @next Success
+ * @next Failure
+ */
+message LoadDevice {
+	optional string mnemonic = 1;				// seed encoded as BIP-39 mnemonic (12, 18 or 24 words)
+	optional HDNodeType node = 2;				// BIP-32 node
+	optional string pin = 3;				// set PIN protection
+	optional bool passphrase_protection = 4;		// enable master node encryption using passphrase
+	optional string language = 5 [default='english'];	// device language
+	optional string label = 6;				// device label
+	optional bool skip_checksum = 7;			// do not test mnemonic for valid BIP-39 checksum
+	optional uint32 u2f_counter = 8;			// U2F counter
+}
+
+/**
+ * Request: Ask device to do initialization involving user interaction
+ * @next EntropyRequest
+ * @next Failure
+ */
+message ResetDevice {
+	optional bool display_random = 1;			// display entropy generated by the device before asking for additional entropy
+	optional uint32 strength = 2 [default=256];		// strength of seed in bits
+	optional bool passphrase_protection = 3;		// enable master node encryption using passphrase
+	optional bool pin_protection = 4;			// enable PIN protection
+	optional string language = 5 [default='english'];	// device language
+	optional string label = 6;				// device label
+	optional uint32 u2f_counter = 7;			// U2F counter
+	optional bool skip_backup = 8;				// postpone seed backup to BackupDevice workflow
+}
+
+/**
+ * Request: Perform backup of the device seed if not backed up using ResetDevice
+ * @next ButtonRequest
+ */
+message BackupDevice {
+}
+
+/**
+ * Response: Ask for additional entropy from host computer
+ * @prev ResetDevice
+ * @next EntropyAck
+ */
+message EntropyRequest {
+}
+
+/**
+ * Request: Provide additional entropy for seed generation function
+ * @prev EntropyRequest
+ * @next ButtonRequest
+ */
+message EntropyAck {
+	optional bytes entropy = 1;				// 256 bits (32 bytes) of random data
+}
+
+/**
+ * Request: Start recovery workflow asking user for specific words of mnemonic
+ * Used to recovery device safely even on untrusted computer.
+ * @next WordRequest
+ */
+message RecoveryDevice {
+	optional uint32 word_count = 1;				// number of words in BIP-39 mnemonic
+	optional bool passphrase_protection = 2;		// enable master node encryption using passphrase
+	optional bool pin_protection = 3;			// enable PIN protection
+	optional string language = 4 [default='english'];	// device language
+	optional string label = 5;				// device label
+	optional bool enforce_wordlist = 6;			// enforce BIP-39 wordlist during the process
+	// 7 reserved for unused recovery method
+	optional uint32 type = 8;				// supported recovery type (see RecoveryType)
+	optional uint32 u2f_counter = 9;			// U2F counter
+	optional bool dry_run = 10;				// perform dry-run recovery workflow (for safe mnemonic validation)
+}
+
+/**
+ * Response: Device is waiting for user to enter word of the mnemonic
+ * Its position is shown only on device's internal display.
+ * @prev RecoveryDevice
+ * @prev WordAck
+ */
+message WordRequest {
+	optional WordRequestType type = 1;
+}
+
+/**
+ * Request: Computer replies with word from the mnemonic
+ * @prev WordRequest
+ * @next WordRequest
+ * @next Success
+ * @next Failure
+ */
+message WordAck {
+	required string word = 1;				// one word of mnemonic on asked position
+}
+
+//////////////////////////////
+// Message signing messages //
+//////////////////////////////
+
+/**
+ * Request: Ask device to sign message
+ * @next MessageSignature
+ * @next Failure
+ */
+message SignMessage {
+	repeated uint32 address_n = 1;						// BIP-32 path to derive the key from master node
+	required bytes message = 2;						// message to be signed
+	optional string coin_name = 3 [default='Bitcoin'];			// coin to use for signing
+	optional InputScriptType script_type = 4 [default=SPENDADDRESS];	// used to distinguish between various address formats (non-segwit, segwit, etc.)
+}
+
+/**
+ * Request: Ask device to verify message
+ * @next Success
+ * @next Failure
+ */
+message VerifyMessage {
+	optional string address = 1;				// address to verify
+	optional bytes signature = 2;				// signature to verify
+	optional bytes message = 3;				// message to verify
+	optional string coin_name = 4 [default='Bitcoin'];	// coin to use for verifying
+}
+
+/**
+ * Response: Signed message
+ * @prev SignMessage
+ */
+message MessageSignature {
+	optional string address = 1;				// address used to sign the message
+	optional bytes signature = 2;				// signature of the message
+}
+
+///////////////////////////
+// Encryption/decryption //
+///////////////////////////
+
+/**
+ * Request: Ask device to encrypt message
+ * @next EncryptedMessage
+ * @next Failure
+ */
+message EncryptMessage {
+	optional bytes pubkey = 1;				// public key
+	optional bytes message = 2;				// message to encrypt
+	optional bool display_only = 3;				// show just on display? (don't send back via wire)
+	repeated uint32 address_n = 4;				// BIP-32 path to derive the signing key from master node
+	optional string coin_name = 5 [default='Bitcoin'];	// coin to use for signing
+}
+
+/**
+ * Response: Encrypted message
+ * @prev EncryptMessage
+ */
+message EncryptedMessage {
+	optional bytes nonce = 1;				// nonce used during encryption
+	optional bytes message = 2;				// encrypted message
+	optional bytes hmac = 3;				// message hmac
+}
+
+/**
+ * Request: Ask device to decrypt message
+ * @next Success
+ * @next Failure
+ */
+message DecryptMessage {
+	repeated uint32 address_n = 1;				// BIP-32 path to derive the decryption key from master node
+	optional bytes nonce = 2;				// nonce used during encryption
+	optional bytes message = 3;				// message to decrypt
+	optional bytes hmac = 4;				// message hmac
+}
+
+/**
+ * Response: Decrypted message
+ * @prev DecryptedMessage
+ */
+message DecryptedMessage {
+	optional bytes message = 1;				// decrypted message
+	optional string address = 2;				// address used to sign the message (if used)
+}
+
+/**
+ * Request: Ask device to encrypt or decrypt value of given key
+ * @next CipheredKeyValue
+ * @next Failure
+ */
+message CipherKeyValue {
+	repeated uint32 address_n = 1;		// BIP-32 path to derive the key from master node
+	optional string key = 2;		// key component of key:value
+	optional bytes value = 3;		// value component of key:value
+	optional bool encrypt = 4;		// are we encrypting (True) or decrypting (False)?
+	optional bool ask_on_encrypt = 5;	// should we ask on encrypt operation?
+	optional bool ask_on_decrypt = 6;	// should we ask on decrypt operation?
+	optional bytes iv = 7;			// initialization vector (will be computed if not set)
+}
+
+/**
+ * Response: Return ciphered/deciphered value
+ * @prev CipherKeyValue
+ */
+message CipheredKeyValue {
+	optional bytes value = 1;		// ciphered/deciphered value
+}
+
+//////////////////////////////////
+// Transaction signing messages //
+//////////////////////////////////
+
+/**
+ * Request: Estimated size of the transaction
+ * This behaves exactly like SignTx, which means that it can ask using TxRequest
+ * This call is non-blocking (except possible PassphraseRequest to unlock the seed)
+ * @next TxSize
+ * @next Failure
+ */
+message EstimateTxSize {
+	required uint32 outputs_count = 1;			// number of transaction outputs
+	required uint32 inputs_count = 2;			// number of transaction inputs
+	optional string coin_name = 3 [default='Bitcoin'];	// coin to use
+}
+
+/**
+ * Response: Estimated size of the transaction
+ * @prev EstimateTxSize
+ */
+message TxSize {
+	optional uint32 tx_size = 1;				// estimated size of transaction in bytes
+}
+
+/**
+ * Request: Ask device to sign transaction
+ * @next PassphraseRequest
+ * @next PinMatrixRequest
+ * @next TxRequest
+ * @next Failure
+ */
+message SignTx {
+	required uint32 outputs_count = 1;			// number of transaction outputs
+	required uint32 inputs_count = 2;			// number of transaction inputs
+	optional string coin_name = 3 [default='Bitcoin'];	// coin to use
+	optional uint32 version = 4 [default=1];		// transaction version
+	optional uint32 lock_time = 5 [default=0];		// transaction lock_time
+}
+
+/**
+ * Request: Simplified transaction signing
+ * This method doesn't support streaming, so there are hardware limits in number of inputs and outputs.
+ * In case of success, the result is returned using TxRequest message.
+ * @next PassphraseRequest
+ * @next PinMatrixRequest
+ * @next TxRequest
+ * @next Failure
+ */
+message SimpleSignTx {
+	repeated TxInputType inputs = 1;			// transaction inputs
+	repeated TxOutputType outputs = 2;			// transaction outputs
+	repeated TransactionType transactions = 3;		// transactions whose outputs are used to build current inputs
+	optional string coin_name = 4 [default='Bitcoin'];	// coin to use
+	optional uint32 version = 5 [default=1];		// transaction version
+	optional uint32 lock_time = 6 [default=0];		// transaction lock_time
+}
+
+/**
+ * Response: Device asks for information for signing transaction or returns the last result
+ * If request_index is set, device awaits TxAck message (with fields filled in according to request_type)
+ * If signature_index is set, 'signature' contains signed input of signature_index's input
+ * @prev SignTx
+ * @prev SimpleSignTx
+ * @prev TxAck
+ */
+message TxRequest {
+	optional RequestType request_type = 1;			// what should be filled in TxAck message?
+	optional TxRequestDetailsType details = 2;		// request for tx details
+	optional TxRequestSerializedType serialized = 3;	// serialized data and request for next
+}
+
+/**
+ * Request: Reported transaction data
+ * @prev TxRequest
+ * @next TxRequest
+ */
+message TxAck {
+	optional TransactionType tx = 1;
+}
+
+/**
+ * Request: Ask device to sign transaction
+ * All fields are optional from the protocol's point of view. Each field defaults to value `0` if missing.
+ * Note: the first at most 1024 bytes of data MUST be transmitted as part of this message.
+ * @next PassphraseRequest
+ * @next PinMatrixRequest
+ * @next EthereumTxRequest
+ * @next Failure
+ */
+message EthereumSignTx {
+	repeated uint32 address_n = 1;			// BIP-32 path to derive the key from master node
+	optional bytes nonce = 2;			// <=256 bit unsigned big endian
+	optional bytes gas_price = 3;			// <=256 bit unsigned big endian (in wei)
+	optional bytes gas_limit = 4;			// <=256 bit unsigned big endian
+	optional bytes to = 5;				// 160 bit address hash
+	optional bytes value = 6;			// <=256 bit unsigned big endian (in wei)
+	optional bytes data_initial_chunk = 7;		// The initial data chunk (<= 1024 bytes)
+	optional uint32 data_length = 8;		// Length of transaction payload
+	optional uint32 chain_id = 9;			// Chain Id for EIP 155
+}
+
+/**
+ * Response: Device asks for more data from transaction payload, or returns the signature.
+ * If data_length is set, device awaits that many more bytes of payload.
+ * Otherwise, the signature_* fields contain the computed transaction signature. All three fields will be present.
+ * @prev EthereumSignTx
+ * @next EthereumTxAck
+ */
+message EthereumTxRequest {
+	optional uint32 data_length = 1;		// Number of bytes being requested (<= 1024)
+	optional uint32 signature_v = 2;		// Computed signature (recovery parameter, limited to 27 or 28)
+	optional bytes signature_r = 3;			// Computed signature R component (256 bit)
+	optional bytes signature_s = 4;			// Computed signature S component (256 bit)
+}
+
+/**
+ * Request: Transaction payload data.
+ * @prev EthereumTxRequest
+ * @next EthereumTxRequest
+ */
+message EthereumTxAck {
+	optional bytes data_chunk = 1;			// Bytes from transaction payload (<= 1024 bytes)
+}
+
+////////////////////////////////////////
+// Ethereum: Message signing messages //
+////////////////////////////////////////
+
+/**
+ * Request: Ask device to sign message
+ * @next EthereumMessageSignature
+ * @next Failure
+ */
+message EthereumSignMessage {
+	repeated uint32 address_n = 1;				// BIP-32 path to derive the key from master node
+	required bytes message = 2;				// message to be signed
+}
+
+/**
+ * Request: Ask device to verify message
+ * @next Success
+ * @next Failure
+ */
+message EthereumVerifyMessage {
+	optional bytes address = 1;				// address to verify
+	optional bytes signature = 2;				// signature to verify
+	optional bytes message = 3;				// message to verify
+}
+
+/**
+ * Response: Signed message
+ * @prev EthereumSignMessage
+ */
+message EthereumMessageSignature {
+	optional bytes address = 1;				// address used to sign the message
+	optional bytes signature = 2;				// signature of the message
+}
+
+///////////////////////
+// Identity messages //
+///////////////////////
+
+/**
+ * Request: Ask device to sign identity
+ * @next SignedIdentity
+ * @next Failure
+ */
+message SignIdentity {
+	optional IdentityType identity = 1;		// identity
+	optional bytes challenge_hidden = 2;		// non-visible challenge
+	optional string challenge_visual = 3;		// challenge shown on display (e.g. date+time)
+	optional string ecdsa_curve_name = 4;		// ECDSA curve name to use
+}
+
+/**
+ * Response: Device provides signed identity
+ * @prev SignIdentity
+ */
+message SignedIdentity {
+	optional string address = 1;			// identity address
+	optional bytes public_key = 2;			// identity public key
+	optional bytes signature = 3;			// signature of the identity data
+}
+
+///////////////////
+// ECDH messages //
+///////////////////
+
+/**
+ * Request: Ask device to generate ECDH session key
+ * @next ECDHSessionKey
+ * @next Failure
+ */
+message GetECDHSessionKey {
+	optional IdentityType identity = 1;		// identity
+	optional bytes peer_public_key = 2;		// peer's public key
+	optional string ecdsa_curve_name = 3;		// ECDSA curve name to use
+}
+
+/**
+ * Response: Device provides ECDH session key
+ * @prev GetECDHSessionKey
+ */
+message ECDHSessionKey {
+	optional bytes session_key = 1;			// ECDH session key
+}
+
+///////////////////
+// U2F messages //
+///////////////////
+
+/**
+ * Request: Set U2F counter
+ * @next Success
+ */
+message SetU2FCounter {
+	optional uint32 u2f_counter = 1;		// counter
+}
+
+/////////////////////////
+// Bootloader messages //
+/////////////////////////
+
+/**
+ * Request: Ask device to erase its firmware (so it can be replaced via FirmwareUpload)
+ * @next Success
+ * @next FirmwareRequest
+ * @next Failure
+ */
+message FirmwareErase {
+	optional uint32 length = 1;			// length of new firmware
+}
+
+/**
+ * Response: Ask for firmware chunk
+ * @next FirmwareUpload
+ */
+message FirmwareRequest {
+	optional uint32 offset = 1;			// offset of requested firmware chunk
+	optional uint32 length = 2;			// length of requested firmware chunk
+}
+
+/**
+ * Request: Send firmware in binary form to the device
+ * @next Success
+ * @next Failure
+ */
+message FirmwareUpload {
+	required bytes payload = 1;			// firmware to be loaded into device
+	optional bytes hash = 2;			// hash of the payload
+}
+
+
+/**
+ * Request: Perform a device self-test
+ * @next Success
+ * @next Failure
+ */
+message SelfTest {
+	optional bytes payload = 1;			// payload to be used in self-test
+}
+
+/////////////////////////////////////////////////////////////
+// Debug messages (only available if DebugLink is enabled) //
+/////////////////////////////////////////////////////////////
+
+/**
+ * Request: "Press" the button on the device
+ * @next Success
+ */
+message DebugLinkDecision {
+	required bool yes_no = 1;			// true for "Confirm", false for "Cancel"
+}
+
+/**
+ * Request: Computer asks for device state
+ * @next DebugLinkState
+ */
+message DebugLinkGetState {
+}
+
+/**
+ * Response: Device current state
+ * @prev DebugLinkGetState
+ */
+message DebugLinkState {
+	optional bytes layout = 1;			// raw buffer of display
+	optional string pin = 2;			// current PIN, blank if PIN is not set/enabled
+	optional string matrix = 3;			// current PIN matrix
+	optional string mnemonic = 4;			// current BIP-39 mnemonic
+	optional HDNodeType node = 5;			// current BIP-32 node
+	optional bool passphrase_protection = 6;	// is node/mnemonic encrypted using passphrase?
+	optional string reset_word = 7;			// word on device display during ResetDevice workflow
+	optional bytes reset_entropy = 8;		// current entropy during ResetDevice workflow
+	optional string recovery_fake_word = 9;		// (fake) word on display during RecoveryDevice workflow
+	optional uint32 recovery_word_pos = 10;		// index of mnemonic word the device is expecting during RecoveryDevice workflow
+}
+
+/**
+ * Request: Ask device to restart
+ */
+message DebugLinkStop {
+}
+
+/**
+ * Response: Device wants host to log event
+ */
+message DebugLinkLog {
+	optional uint32 level = 1;
+	optional string bucket = 2;
+	optional string text = 3;
+}
+
+/**
+ * Request: Read memory from device
+ * @next DebugLinkMemory
+ */
+message DebugLinkMemoryRead {
+	optional uint32 address = 1;
+	optional uint32 length = 2;
+}
+
+/**
+ * Response: Device sends memory back
+ * @prev DebugLinkMemoryRead
+ */
+message DebugLinkMemory {
+	optional bytes memory = 1;
+}
+
+/**
+ * Request: Write memory to device.
+ * WARNING: Writing to the wrong location can irreparably break the device.
+ */
+message DebugLinkMemoryWrite {
+	optional uint32 address = 1;
+	optional bytes memory = 2;
+	optional bool flash = 3;
+}
+
+/**
+ * Request: Erase block of flash on device
+ * WARNING: Writing to the wrong location can irreparably break the device.
+ */
+message DebugLinkFlashErase {
+	optional uint32 sector = 1;
+}
--- a/accounts/usbwallet/internal/trezor/trezor.go
+++ b/accounts/usbwallet/internal/trezor/trezor.go
@@ -0,0 +1,46 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// This file contains the implementation for interacting with the Trezor hardware
+// wallets. The wire protocol spec can be found on the SatoshiLabs website:
+// https://doc.satoshilabs.com/trezor-tech/api-protobuf.html
+
+//go:generate protoc --go_out=import_path=trezor:. types.proto messages.proto
+
+// Package trezor contains the wire protocol wrapper in Go.
+package trezor
+
+import (
+	"reflect"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// Type returns the protocol buffer type number of a specific message. If the
+// message is nil, this method panics!
+func Type(msg proto.Message) uint16 {
+	return uint16(MessageType_value["MessageType_"+reflect.TypeOf(msg).Elem().Name()])
+}
+
+// Name returns the friendly message type name of a specific protocol buffer
+// type numbers.
+func Name(kind uint16) string {
+	name := MessageType_name[int32(kind)]
+	if len(name) < 12 {
+		return name
+	}
+	return name[12:]
+}
--- a/accounts/usbwallet/internal/trezor/types.pb.go
+++ b/accounts/usbwallet/internal/trezor/types.pb.go
--- a/accounts/usbwallet/internal/trezor/types.proto
+++ b/accounts/usbwallet/internal/trezor/types.proto
@@ -0,0 +1,278 @@
+// This file originates from the SatoshiLabs Trezor `common` repository at:
+//   https://github.com/trezor/trezor-common/blob/master/protob/types.proto
+// dated 28.07.2017, commit dd8ec3231fb5f7992360aff9bdfe30bb58130f4b.
+
+syntax = "proto2";
+
+/**
+ * Types for TREZOR communication
+ *
+ * @author	Marek Palatinus <slush@satoshilabs.com>
+ * @version	1.2
+ */
+
+// Sugar for easier handling in Java
+option java_package = "com.satoshilabs.trezor.lib.protobuf";
+option java_outer_classname = "TrezorType";
+
+import "google/protobuf/descriptor.proto";
+
+/**
+ * Options for specifying message direction and type of wire (normal/debug)
+ */
+extend google.protobuf.EnumValueOptions {
+	optional bool wire_in = 50002;		// message can be transmitted via wire from PC to TREZOR
+	optional bool wire_out = 50003;		// message can be transmitted via wire from TREZOR to PC
+	optional bool wire_debug_in = 50004;	// message can be transmitted via debug wire from PC to TREZOR
+	optional bool wire_debug_out = 50005;	// message can be transmitted via debug wire from TREZOR to PC
+	optional bool wire_tiny = 50006;	// message is handled by TREZOR when the USB stack is in tiny mode
+	optional bool wire_bootloader = 50007;  // message is only handled by TREZOR Bootloader
+}
+
+/**
+ * Type of failures returned by Failure message
+ * @used_in Failure
+ */
+enum FailureType {
+	Failure_UnexpectedMessage = 1;
+	Failure_ButtonExpected = 2;
+	Failure_DataError = 3;
+	Failure_ActionCancelled = 4;
+	Failure_PinExpected = 5;
+	Failure_PinCancelled = 6;
+	Failure_PinInvalid = 7;
+	Failure_InvalidSignature = 8;
+	Failure_ProcessError = 9;
+	Failure_NotEnoughFunds = 10;
+	Failure_NotInitialized = 11;
+	Failure_FirmwareError = 99;
+}
+
+/**
+ * Type of script which will be used for transaction output
+ * @used_in TxOutputType
+ */
+enum OutputScriptType {
+	PAYTOADDRESS = 0;	// used for all addresses (bitcoin, p2sh, witness)
+	PAYTOSCRIPTHASH = 1;	// p2sh address (deprecated; use PAYTOADDRESS)
+	PAYTOMULTISIG = 2;	// only for change output
+	PAYTOOPRETURN = 3;	// op_return
+	PAYTOWITNESS = 4;	// only for change output
+	PAYTOP2SHWITNESS = 5;	// only for change output
+}
+
+/**
+ * Type of script which will be used for transaction output
+ * @used_in TxInputType
+ */
+enum InputScriptType {
+	SPENDADDRESS = 0;		// standard p2pkh address
+	SPENDMULTISIG = 1;		// p2sh multisig address
+	EXTERNAL = 2;			// reserved for external inputs (coinjoin)
+	SPENDWITNESS = 3;		// native segwit
+	SPENDP2SHWITNESS = 4;		// segwit over p2sh (backward compatible)
+}
+
+/**
+ * Type of information required by transaction signing process
+ * @used_in TxRequest
+ */
+enum RequestType {
+	TXINPUT = 0;
+	TXOUTPUT = 1;
+	TXMETA = 2;
+	TXFINISHED = 3;
+	TXEXTRADATA = 4;
+}
+
+/**
+ * Type of button request
+ * @used_in ButtonRequest
+ */
+enum ButtonRequestType {
+	ButtonRequest_Other = 1;
+	ButtonRequest_FeeOverThreshold = 2;
+	ButtonRequest_ConfirmOutput = 3;
+	ButtonRequest_ResetDevice = 4;
+	ButtonRequest_ConfirmWord = 5;
+	ButtonRequest_WipeDevice = 6;
+	ButtonRequest_ProtectCall = 7;
+	ButtonRequest_SignTx = 8;
+	ButtonRequest_FirmwareCheck = 9;
+	ButtonRequest_Address = 10;
+	ButtonRequest_PublicKey = 11;
+}
+
+/**
+ * Type of PIN request
+ * @used_in PinMatrixRequest
+ */
+enum PinMatrixRequestType {
+	PinMatrixRequestType_Current = 1;
+	PinMatrixRequestType_NewFirst = 2;
+	PinMatrixRequestType_NewSecond = 3;
+}
+
+/**
+ * Type of recovery procedure. These should be used as bitmask, e.g.,
+ * `RecoveryDeviceType_ScrambledWords | RecoveryDeviceType_Matrix`
+ * listing every method supported by the host computer.
+ *
+ * Note that ScrambledWords must be supported by every implementation
+ * for backward compatibility; there is no way to not support it.
+ *
+ * @used_in RecoveryDevice
+ */
+enum RecoveryDeviceType {
+	// use powers of two when extending this field
+	RecoveryDeviceType_ScrambledWords = 0;		// words in scrambled order
+	RecoveryDeviceType_Matrix = 1;				// matrix recovery type
+}
+
+/**
+ * Type of Recovery Word request
+ * @used_in WordRequest
+ */
+enum WordRequestType {
+	WordRequestType_Plain = 0;
+	WordRequestType_Matrix9 = 1;
+	WordRequestType_Matrix6 = 2;
+}
+
+/**
+ * Structure representing BIP32 (hierarchical deterministic) node
+ * Used for imports of private key into the device and exporting public key out of device
+ * @used_in PublicKey
+ * @used_in LoadDevice
+ * @used_in DebugLinkState
+ * @used_in Storage
+ */
+message HDNodeType {
+	required uint32 depth = 1;
+	required uint32 fingerprint = 2;
+	required uint32 child_num = 3;
+	required bytes chain_code = 4;
+	optional bytes private_key = 5;
+	optional bytes public_key = 6;
+}
+
+message HDNodePathType {
+	required HDNodeType node = 1;						// BIP-32 node in deserialized form
+	repeated uint32 address_n = 2;						// BIP-32 path to derive the key from node
+}
+
+/**
+ * Structure representing Coin
+ * @used_in Features
+ */
+message CoinType {
+	optional string coin_name = 1;
+	optional string coin_shortcut = 2;
+	optional uint32 address_type = 3 [default=0];
+	optional uint64 maxfee_kb = 4;
+	optional uint32 address_type_p2sh = 5 [default=5];
+	optional string signed_message_header = 8;
+	optional uint32 xpub_magic = 9 [default=76067358];	// default=0x0488b21e
+	optional uint32 xprv_magic = 10 [default=76066276];	// default=0x0488ade4
+	optional bool segwit = 11;
+	optional uint32 forkid = 12;
+}
+
+/**
+ * Type of redeem script used in input
+ * @used_in TxInputType
+ */
+message MultisigRedeemScriptType {
+	repeated HDNodePathType pubkeys = 1;					// pubkeys from multisig address (sorted lexicographically)
+	repeated bytes signatures = 2;						// existing signatures for partially signed input
+	optional uint32 m = 3;							// "m" from n, how many valid signatures is necessary for spending
+}
+
+/**
+ * Structure representing transaction input
+ * @used_in SimpleSignTx
+ * @used_in TransactionType
+ */
+message TxInputType {
+	repeated uint32 address_n = 1;						// BIP-32 path to derive the key from master node
+	required bytes prev_hash = 2;						// hash of previous transaction output to spend by this input
+	required uint32 prev_index = 3;						// index of previous output to spend
+	optional bytes script_sig = 4;						// script signature, unset for tx to sign
+	optional uint32 sequence = 5 [default=4294967295];			// sequence (default=0xffffffff)
+	optional InputScriptType script_type = 6 [default=SPENDADDRESS];	// defines template of input script
+	optional MultisigRedeemScriptType multisig = 7;				// Filled if input is going to spend multisig tx
+	optional uint64 amount = 8;						// amount of previous transaction output (for segwit only)
+}
+
+/**
+ * Structure representing transaction output
+ * @used_in SimpleSignTx
+ * @used_in TransactionType
+ */
+message TxOutputType {
+	optional string address = 1;			// target coin address in Base58 encoding
+	repeated uint32 address_n = 2;			// BIP-32 path to derive the key from master node; has higher priority than "address"
+	required uint64 amount = 3;			// amount to spend in satoshis
+	required OutputScriptType script_type = 4;	// output script type
+	optional MultisigRedeemScriptType multisig = 5; // defines multisig address; script_type must be PAYTOMULTISIG
+	optional bytes op_return_data = 6;		// defines op_return data; script_type must be PAYTOOPRETURN, amount must be 0
+}
+
+/**
+ * Structure representing compiled transaction output
+ * @used_in TransactionType
+ */
+message TxOutputBinType {
+	required uint64 amount = 1;
+	required bytes script_pubkey = 2;
+}
+
+/**
+ * Structure representing transaction
+ * @used_in SimpleSignTx
+ */
+message TransactionType {
+	optional uint32 version = 1;
+	repeated TxInputType inputs = 2;
+	repeated TxOutputBinType bin_outputs = 3;
+	repeated TxOutputType outputs = 5;
+	optional uint32 lock_time = 4;
+	optional uint32 inputs_cnt = 6;
+	optional uint32 outputs_cnt = 7;
+	optional bytes extra_data = 8;
+	optional uint32 extra_data_len = 9;
+}
+
+/**
+ * Structure representing request details
+ * @used_in TxRequest
+ */
+message TxRequestDetailsType {
+	optional uint32 request_index = 1;	// device expects TxAck message from the computer
+	optional bytes tx_hash = 2;		// tx_hash of requested transaction
+	optional uint32 extra_data_len = 3;	// length of requested extra data
+	optional uint32 extra_data_offset = 4;	// offset of requested extra data
+}
+
+/**
+ * Structure representing serialized data
+ * @used_in TxRequest
+ */
+message TxRequestSerializedType {
+	optional uint32 signature_index = 1;	// 'signature' field contains signed input of this index
+	optional bytes signature = 2;		// signature of the signature_index input
+	optional bytes serialized_tx = 3;	// part of serialized and signed transaction
+}
+
+/**
+ * Structure representing identity data
+ * @used_in IdentityType
+ */
+message IdentityType {
+	optional string proto = 1;			// proto part of URI
+	optional string user = 2;			// user part of URI
+	optional string host = 3;			// host part of URI
+	optional string port = 4;			// port part of URI
+	optional string path = 5;			// path part of URI
+	optional uint32 index = 6 [default=0];		// identity index
+}
--- a/accounts/usbwallet/ledger.go
+++ b/accounts/usbwallet/ledger.go
@@ -0,0 +1,464 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// This file contains the implementation for interacting with the Ledger hardware
+// wallets. The wire protocol spec can be found in the Ledger Blue GitHub repo:
+// https://raw.githubusercontent.com/LedgerHQ/blue-app-eth/master/doc/ethapp.asc
+
+package usbwallet
+
+import (
+	"encoding/binary"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/rlp"
+)
+
+// ledgerOpcode is an enumeration encoding the supported Ledger opcodes.
+type ledgerOpcode byte
+
+// ledgerParam1 is an enumeration encoding the supported Ledger parameters for
+// specific opcodes. The same parameter values may be reused between opcodes.
+type ledgerParam1 byte
+
+// ledgerParam2 is an enumeration encoding the supported Ledger parameters for
+// specific opcodes. The same parameter values may be reused between opcodes.
+type ledgerParam2 byte
+
+const (
+	ledgerOpRetrieveAddress  ledgerOpcode = 0x02 // Returns the public key and Ethereum address for a given BIP 32 path
+	ledgerOpSignTransaction  ledgerOpcode = 0x04 // Signs an Ethereum transaction after having the user validate the parameters
+	ledgerOpGetConfiguration ledgerOpcode = 0x06 // Returns specific wallet application configuration
+
+	ledgerP1DirectlyFetchAddress    ledgerParam1 = 0x00 // Return address directly from the wallet
+	ledgerP1ConfirmFetchAddress     ledgerParam1 = 0x01 // Require a user confirmation before returning the address
+	ledgerP1InitTransactionData     ledgerParam1 = 0x00 // First transaction data block for signing
+	ledgerP1ContTransactionData     ledgerParam1 = 0x80 // Subsequent transaction data block for signing
+	ledgerP2DiscardAddressChainCode ledgerParam2 = 0x00 // Do not return the chain code along with the address
+	ledgerP2ReturnAddressChainCode  ledgerParam2 = 0x01 // Require a user confirmation before returning the address
+)
+
+// errLedgerReplyInvalidHeader is the error message returned by a Ledger data exchange
+// if the device replies with a mismatching header. This usually means the device
+// is in browser mode.
+var errLedgerReplyInvalidHeader = errors.New("ledger: invalid reply header")
+
+// errLedgerInvalidVersionReply is the error message returned by a Ledger version retrieval
+// when a response does arrive, but it does not contain the expected data.
+var errLedgerInvalidVersionReply = errors.New("ledger: invalid version reply")
+
+// ledgerDriver implements the communication with a Ledger hardware wallet.
+type ledgerDriver struct {
+	device  io.ReadWriter // USB device connection to communicate through
+	version [3]byte       // Current version of the Ledger firmware (zero if app is offline)
+	browser bool          // Flag whether the Ledger is in browser mode (reply channel mismatch)
+	failure error         // Any failure that would make the device unusable
+	log     log.Logger    // Contextual logger to tag the ledger with its id
+}
+
+// newLedgerDriver creates a new instance of a Ledger USB protocol driver.
+func newLedgerDriver(logger log.Logger) driver {
+	return &ledgerDriver{
+		log: logger,
+	}
+}
+
+// Status implements usbwallet.driver, returning various states the Ledger can
+// currently be in.
+func (w *ledgerDriver) Status() (string, error) {
+	if w.failure != nil {
+		return fmt.Sprintf("Failed: %v", w.failure), w.failure
+	}
+	if w.browser {
+		return "Ethereum app in browser mode", w.failure
+	}
+	if w.offline() {
+		return "Ethereum app offline", w.failure
+	}
+	return fmt.Sprintf("Ethereum app v%d.%d.%d online", w.version[0], w.version[1], w.version[2]), w.failure
+}
+
+// offline returns whether the wallet and the Ethereum app is offline or not.
+//
+// The method assumes that the state lock is held!
+func (w *ledgerDriver) offline() bool {
+	return w.version == [3]byte{0, 0, 0}
+}
+
+// Open implements usbwallet.driver, attempting to initialize the connection to the
+// Ledger hardware wallet. The Ledger does not require a user passphrase, so that
+// parameter is silently discarded.
+func (w *ledgerDriver) Open(device io.ReadWriter, passphrase string) error {
+	w.device, w.failure = device, nil
+
+	_, err := w.ledgerDerive(accounts.DefaultBaseDerivationPath)
+	if err != nil {
+		// Ethereum app is not running or in browser mode, nothing more to do, return
+		if err == errLedgerReplyInvalidHeader {
+			w.browser = true
+		}
+		return nil
+	}
+	// Try to resolve the Ethereum app's version, will fail prior to v1.0.2
+	if w.version, err = w.ledgerVersion(); err != nil {
+		w.version = [3]byte{1, 0, 0} // Assume worst case, can't verify if v1.0.0 or v1.0.1
+	}
+	return nil
+}
+
+// Close implements usbwallet.driver, cleaning up and metadata maintained within
+// the Ledger driver.
+func (w *ledgerDriver) Close() error {
+	w.browser, w.version = false, [3]byte{}
+	return nil
+}
+
+// Heartbeat implements usbwallet.driver, performing a sanity check against the
+// Ledger to see if it's still online.
+func (w *ledgerDriver) Heartbeat() error {
+	if _, err := w.ledgerVersion(); err != nil && err != errLedgerInvalidVersionReply {
+		w.failure = err
+		return err
+	}
+	return nil
+}
+
+// Derive implements usbwallet.driver, sending a derivation request to the Ledger
+// and returning the Ethereum address located on that derivation path.
+func (w *ledgerDriver) Derive(path accounts.DerivationPath) (common.Address, error) {
+	return w.ledgerDerive(path)
+}
+
+// SignTx implements usbwallet.driver, sending the transaction to the Ledger and
+// waiting for the user to confirm or deny the transaction.
+//
+// Note, if the version of the Ethereum application running on the Ledger wallet is
+// too old to sign EIP-155 transactions, but such is requested nonetheless, an error
+// will be returned opposed to silently signing in Homestead mode.
+func (w *ledgerDriver) SignTx(path accounts.DerivationPath, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
+	// If the Ethereum app doesn't run, abort
+	if w.offline() {
+		return common.Address{}, nil, accounts.ErrWalletClosed
+	}
+	// Ensure the wallet is capable of signing the given transaction
+	if chainID != nil && w.version[0] <= 1 && w.version[1] <= 0 && w.version[2] <= 2 {
+		return common.Address{}, nil, fmt.Errorf("Ledger v%d.%d.%d doesn't support signing this transaction, please update to v1.0.3 at least", w.version[0], w.version[1], w.version[2])
+	}
+	// All infos gathered and metadata checks out, request signing
+	return w.ledgerSign(path, tx, chainID)
+}
+
+// ledgerVersion retrieves the current version of the Ethereum wallet app running
+// on the Ledger wallet.
+//
+// The version retrieval protocol is defined as follows:
+//
+//   CLA | INS | P1 | P2 | Lc | Le
+//   ----+-----+----+----+----+---
+//    E0 | 06  | 00 | 00 | 00 | 04
+//
+// With no input data, and the output data being:
+//
+//   Description                                        | Length
+//   ---------------------------------------------------+--------
+//   Flags 01: arbitrary data signature enabled by user | 1 byte
+//   Application major version                          | 1 byte
+//   Application minor version                          | 1 byte
+//   Application patch version                          | 1 byte
+func (w *ledgerDriver) ledgerVersion() ([3]byte, error) {
+	// Send the request and wait for the response
+	reply, err := w.ledgerExchange(ledgerOpGetConfiguration, 0, 0, nil)
+	if err != nil {
+		return [3]byte{}, err
+	}
+	if len(reply) != 4 {
+		return [3]byte{}, errLedgerInvalidVersionReply
+	}
+	// Cache the version for future reference
+	var version [3]byte
+	copy(version[:], reply[1:])
+	return version, nil
+}
+
+// ledgerDerive retrieves the currently active Ethereum address from a Ledger
+// wallet at the specified derivation path.
+//
+// The address derivation protocol is defined as follows:
+//
+//   CLA | INS | P1 | P2 | Lc  | Le
+//   ----+-----+----+----+-----+---
+//    E0 | 02  | 00 return address
+//               01 display address and confirm before returning
+//                  | 00: do not return the chain code
+//                  | 01: return the chain code
+//                       | var | 00
+//
+// Where the input data is:
+//
+//   Description                                      | Length
+//   -------------------------------------------------+--------
+//   Number of BIP 32 derivations to perform (max 10) | 1 byte
+//   First derivation index (big endian)              | 4 bytes
+//   ...                                              | 4 bytes
+//   Last derivation index (big endian)               | 4 bytes
+//
+// And the output data is:
+//
+//   Description             | Length
+//   ------------------------+-------------------
+//   Public Key length       | 1 byte
+//   Uncompressed Public Key | arbitrary
+//   Ethereum address length | 1 byte
+//   Ethereum address        | 40 bytes hex ascii
+//   Chain code if requested | 32 bytes
+func (w *ledgerDriver) ledgerDerive(derivationPath []uint32) (common.Address, error) {
+	// Flatten the derivation path into the Ledger request
+	path := make([]byte, 1+4*len(derivationPath))
+	path[0] = byte(len(derivationPath))
+	for i, component := range derivationPath {
+		binary.BigEndian.PutUint32(path[1+4*i:], component)
+	}
+	// Send the request and wait for the response
+	reply, err := w.ledgerExchange(ledgerOpRetrieveAddress, ledgerP1DirectlyFetchAddress, ledgerP2DiscardAddressChainCode, path)
+	if err != nil {
+		return common.Address{}, err
+	}
+	// Discard the public key, we don't need that for now
+	if len(reply) < 1 || len(reply) < 1+int(reply[0]) {
+		return common.Address{}, errors.New("reply lacks public key entry")
+	}
+	reply = reply[1+int(reply[0]):]
+
+	// Extract the Ethereum hex address string
+	if len(reply) < 1 || len(reply) < 1+int(reply[0]) {
+		return common.Address{}, errors.New("reply lacks address entry")
+	}
+	hexstr := reply[1 : 1+int(reply[0])]
+
+	// Decode the hex sting into an Ethereum address and return
+	var address common.Address
+	hex.Decode(address[:], hexstr)
+	return address, nil
+}
+
+// ledgerSign sends the transaction to the Ledger wallet, and waits for the user
+// to confirm or deny the transaction.
+//
+// The transaction signing protocol is defined as follows:
+//
+//   CLA | INS | P1 | P2 | Lc  | Le
+//   ----+-----+----+----+-----+---
+//    E0 | 04  | 00: first transaction data block
+//               80: subsequent transaction data block
+//                  | 00 | variable | variable
+//
+// Where the input for the first transaction block (first 255 bytes) is:
+//
+//   Description                                      | Length
+//   -------------------------------------------------+----------
+//   Number of BIP 32 derivations to perform (max 10) | 1 byte
+//   First derivation index (big endian)              | 4 bytes
+//   ...                                              | 4 bytes
+//   Last derivation index (big endian)               | 4 bytes
+//   RLP transaction chunk                            | arbitrary
+//
+// And the input for subsequent transaction blocks (first 255 bytes) are:
+//
+//   Description           | Length
+//   ----------------------+----------
+//   RLP transaction chunk | arbitrary
+//
+// And the output data is:
+//
+//   Description | Length
+//   ------------+---------
+//   signature V | 1 byte
+//   signature R | 32 bytes
+//   signature S | 32 bytes
+func (w *ledgerDriver) ledgerSign(derivationPath []uint32, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
+	// Flatten the derivation path into the Ledger request
+	path := make([]byte, 1+4*len(derivationPath))
+	path[0] = byte(len(derivationPath))
+	for i, component := range derivationPath {
+		binary.BigEndian.PutUint32(path[1+4*i:], component)
+	}
+	// Create the transaction RLP based on whether legacy or EIP155 signing was requeste
+	var (
+		txrlp []byte
+		err   error
+	)
+	if chainID == nil {
+		if txrlp, err = rlp.EncodeToBytes([]interface{}{tx.Nonce(), tx.GasPrice(), tx.Gas(), tx.To(), tx.Value(), tx.Data()}); err != nil {
+			return common.Address{}, nil, err
+		}
+	} else {
+		if txrlp, err = rlp.EncodeToBytes([]interface{}{tx.Nonce(), tx.GasPrice(), tx.Gas(), tx.To(), tx.Value(), tx.Data(), chainID, big.NewInt(0), big.NewInt(0)}); err != nil {
+			return common.Address{}, nil, err
+		}
+	}
+	payload := append(path, txrlp...)
+
+	// Send the request and wait for the response
+	var (
+		op    = ledgerP1InitTransactionData
+		reply []byte
+	)
+	for len(payload) > 0 {
+		// Calculate the size of the next data chunk
+		chunk := 255
+		if chunk > len(payload) {
+			chunk = len(payload)
+		}
+		// Send the chunk over, ensuring it's processed correctly
+		reply, err = w.ledgerExchange(ledgerOpSignTransaction, op, 0, payload[:chunk])
+		if err != nil {
+			return common.Address{}, nil, err
+		}
+		// Shift the payload and ensure subsequent chunks are marked as such
+		payload = payload[chunk:]
+		op = ledgerP1ContTransactionData
+	}
+	// Extract the Ethereum signature and do a sanity validation
+	if len(reply) != 65 {
+		return common.Address{}, nil, errors.New("reply lacks signature")
+	}
+	signature := append(reply[1:], reply[0])
+
+	// Create the correct signer and signature transform based on the chain ID
+	var signer types.Signer
+	if chainID == nil {
+		signer = new(types.HomesteadSigner)
+	} else {
+		signer = types.NewEIP155Signer(chainID)
+		signature[64] = signature[64] - byte(chainID.Uint64()*2+35)
+	}
+	signed, err := tx.WithSignature(signer, signature)
+	if err != nil {
+		return common.Address{}, nil, err
+	}
+	sender, err := types.Sender(signer, signed)
+	if err != nil {
+		return common.Address{}, nil, err
+	}
+	return sender, signed, nil
+}
+
+// ledgerExchange performs a data exchange with the Ledger wallet, sending it a
+// message and retrieving the response.
+//
+// The common transport header is defined as follows:
+//
+//  Description                           | Length
+//  --------------------------------------+----------
+//  Communication channel ID (big endian) | 2 bytes
+//  Command tag                           | 1 byte
+//  Packet sequence index (big endian)    | 2 bytes
+//  Payload                               | arbitrary
+//
+// The Communication channel ID allows commands multiplexing over the same
+// physical link. It is not used for the time being, and should be set to 0101
+// to avoid compatibility issues with implementations ignoring a leading 00 byte.
+//
+// The Command tag describes the message content. Use TAG_APDU (0x05) for standard
+// APDU payloads, or TAG_PING (0x02) for a simple link test.
+//
+// The Packet sequence index describes the current sequence for fragmented payloads.
+// The first fragment index is 0x00.
+//
+// APDU Command payloads are encoded as follows:
+//
+//  Description              | Length
+//  -----------------------------------
+//  APDU length (big endian) | 2 bytes
+//  APDU CLA                 | 1 byte
+//  APDU INS                 | 1 byte
+//  APDU P1                  | 1 byte
+//  APDU P2                  | 1 byte
+//  APDU length              | 1 byte
+//  Optional APDU data       | arbitrary
+func (w *ledgerDriver) ledgerExchange(opcode ledgerOpcode, p1 ledgerParam1, p2 ledgerParam2, data []byte) ([]byte, error) {
+	// Construct the message payload, possibly split into multiple chunks
+	apdu := make([]byte, 2, 7+len(data))
+
+	binary.BigEndian.PutUint16(apdu, uint16(5+len(data)))
+	apdu = append(apdu, []byte{0xe0, byte(opcode), byte(p1), byte(p2), byte(len(data))}...)
+	apdu = append(apdu, data...)
+
+	// Stream all the chunks to the device
+	header := []byte{0x01, 0x01, 0x05, 0x00, 0x00} // Channel ID and command tag appended
+	chunk := make([]byte, 64)
+	space := len(chunk) - len(header)
+
+	for i := 0; len(apdu) > 0; i++ {
+		// Construct the new message to stream
+		chunk = append(chunk[:0], header...)
+		binary.BigEndian.PutUint16(chunk[3:], uint16(i))
+
+		if len(apdu) > space {
+			chunk = append(chunk, apdu[:space]...)
+			apdu = apdu[space:]
+		} else {
+			chunk = append(chunk, apdu...)
+			apdu = nil
+		}
+		// Send over to the device
+		w.log.Trace("Data chunk sent to the Ledger", "chunk", hexutil.Bytes(chunk))
+		if _, err := w.device.Write(chunk); err != nil {
+			return nil, err
+		}
+	}
+	// Stream the reply back from the wallet in 64 byte chunks
+	var reply []byte
+	chunk = chunk[:64] // Yeah, we surely have enough space
+	for {
+		// Read the next chunk from the Ledger wallet
+		if _, err := io.ReadFull(w.device, chunk); err != nil {
+			return nil, err
+		}
+		w.log.Trace("Data chunk received from the Ledger", "chunk", hexutil.Bytes(chunk))
+
+		// Make sure the transport header matches
+		if chunk[0] != 0x01 || chunk[1] != 0x01 || chunk[2] != 0x05 {
+			return nil, errLedgerReplyInvalidHeader
+		}
+		// If it's the first chunk, retrieve the total message length
+		var payload []byte
+
+		if chunk[3] == 0x00 && chunk[4] == 0x00 {
+			reply = make([]byte, 0, int(binary.BigEndian.Uint16(chunk[5:7])))
+			payload = chunk[7:]
+		} else {
+			payload = chunk[5:]
+		}
+		// Append to the reply and stop when filled up
+		if left := cap(reply) - len(reply); left > len(payload) {
+			reply = append(reply, payload...)
+		} else {
+			reply = append(reply, payload[:left]...)
+			break
+		}
+	}
+	return reply[:len(reply)-2], nil
+}
--- a/accounts/usbwallet/trezor.go
+++ b/accounts/usbwallet/trezor.go
@@ -0,0 +1,330 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// This file contains the implementation for interacting with the Trezor hardware
+// wallets. The wire protocol spec can be found on the SatoshiLabs website:
+// https://doc.satoshilabs.com/trezor-tech/api-protobuf.html
+
+package usbwallet
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/accounts/usbwallet/internal/trezor"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/golang/protobuf/proto"
+)
+
+// ErrTrezorPINNeeded is returned if opening the trezor requires a PIN code. In
+// this case, the calling application should display a pinpad and send back the
+// encoded passphrase.
+var ErrTrezorPINNeeded = errors.New("trezor: pin needed")
+
+// errTrezorReplyInvalidHeader is the error message returned by a Trezor data exchange
+// if the device replies with a mismatching header. This usually means the device
+// is in browser mode.
+var errTrezorReplyInvalidHeader = errors.New("trezor: invalid reply header")
+
+// trezorDriver implements the communication with a Trezor hardware wallet.
+type trezorDriver struct {
+	device  io.ReadWriter // USB device connection to communicate through
+	version [3]uint32     // Current version of the Trezor firmware
+	label   string        // Current textual label of the Trezor device
+	pinwait bool          // Flags whether the device is waiting for PIN entry
+	failure error         // Any failure that would make the device unusable
+	log     log.Logger    // Contextual logger to tag the trezor with its id
+}
+
+// newTrezorDriver creates a new instance of a Trezor USB protocol driver.
+func newTrezorDriver(logger log.Logger) driver {
+	return &trezorDriver{
+		log: logger,
+	}
+}
+
+// Status implements accounts.Wallet, always whether the Trezor is opened, closed
+// or whether the Ethereum app was not started on it.
+func (w *trezorDriver) Status() (string, error) {
+	if w.failure != nil {
+		return fmt.Sprintf("Failed: %v", w.failure), w.failure
+	}
+	if w.device == nil {
+		return "Closed", w.failure
+	}
+	if w.pinwait {
+		return fmt.Sprintf("Trezor v%d.%d.%d '%s' waiting for PIN", w.version[0], w.version[1], w.version[2], w.label), w.failure
+	}
+	return fmt.Sprintf("Trezor v%d.%d.%d '%s' online", w.version[0], w.version[1], w.version[2], w.label), w.failure
+}
+
+// Open implements usbwallet.driver, attempting to initialize the connection to
+// the Trezor hardware wallet. Initializing the Trezor is a two phase operation:
+//  * The first phase is to initialize the connection and read the wallet's
+//    features. This phase is invoked is the provided passphrase is empty. The
+//    device will display the pinpad as a result and will return an appropriate
+//    error to notify the user that a second open phase is needed.
+//  * The second phase is to unlock access to the Trezor, which is done by the
+//    user actually providing a passphrase mapping a keyboard keypad to the pin
+//    number of the user (shuffled according to the pinpad displayed).
+func (w *trezorDriver) Open(device io.ReadWriter, passphrase string) error {
+	w.device, w.failure = device, nil
+
+	// If phase 1 is requested, init the connection and wait for user callback
+	if passphrase == "" {
+		// If we're already waiting for a PIN entry, insta-return
+		if w.pinwait {
+			return ErrTrezorPINNeeded
+		}
+		// Initialize a connection to the device
+		features := new(trezor.Features)
+		if _, err := w.trezorExchange(&trezor.Initialize{}, features); err != nil {
+			return err
+		}
+		w.version = [3]uint32{features.GetMajorVersion(), features.GetMinorVersion(), features.GetPatchVersion()}
+		w.label = features.GetLabel()
+
+		// Do a manual ping, forcing the device to ask for its PIN
+		askPin := true
+		res, err := w.trezorExchange(&trezor.Ping{PinProtection: &askPin}, new(trezor.PinMatrixRequest), new(trezor.Success))
+		if err != nil {
+			return err
+		}
+		// Only return the PIN request if the device wasn't unlocked until now
+		if res == 1 {
+			return nil // Device responded with trezor.Success
+		}
+		w.pinwait = true
+		return ErrTrezorPINNeeded
+	}
+	// Phase 2 requested with actual PIN entry
+	w.pinwait = false
+
+	if _, err := w.trezorExchange(&trezor.PinMatrixAck{Pin: &passphrase}, new(trezor.Success)); err != nil {
+		w.failure = err
+		return err
+	}
+	return nil
+}
+
+// Close implements usbwallet.driver, cleaning up and metadata maintained within
+// the Trezor driver.
+func (w *trezorDriver) Close() error {
+	w.version, w.label, w.pinwait = [3]uint32{}, "", false
+	return nil
+}
+
+// Heartbeat implements usbwallet.driver, performing a sanity check against the
+// Trezor to see if it's still online.
+func (w *trezorDriver) Heartbeat() error {
+	if _, err := w.trezorExchange(&trezor.Ping{}, new(trezor.Success)); err != nil {
+		w.failure = err
+		return err
+	}
+	return nil
+}
+
+// Derive implements usbwallet.driver, sending a derivation request to the Trezor
+// and returning the Ethereum address located on that derivation path.
+func (w *trezorDriver) Derive(path accounts.DerivationPath) (common.Address, error) {
+	return w.trezorDerive(path)
+}
+
+// SignTx implements usbwallet.driver, sending the transaction to the Trezor and
+// waiting for the user to confirm or deny the transaction.
+func (w *trezorDriver) SignTx(path accounts.DerivationPath, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
+	if w.device == nil {
+		return common.Address{}, nil, accounts.ErrWalletClosed
+	}
+	return w.trezorSign(path, tx, chainID)
+}
+
+// trezorDerive sends a derivation request to the Trezor device and returns the
+// Ethereum address located on that path.
+func (w *trezorDriver) trezorDerive(derivationPath []uint32) (common.Address, error) {
+	address := new(trezor.EthereumAddress)
+	if _, err := w.trezorExchange(&trezor.EthereumGetAddress{AddressN: derivationPath}, address); err != nil {
+		return common.Address{}, err
+	}
+	return common.BytesToAddress(address.GetAddress()), nil
+}
+
+// trezorSign sends the transaction to the Trezor wallet, and waits for the user
+// to confirm or deny the transaction.
+func (w *trezorDriver) trezorSign(derivationPath []uint32, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
+	// Create the transaction initiation message
+	data := tx.Data()
+	length := uint32(len(data))
+
+	request := &trezor.EthereumSignTx{
+		AddressN:   derivationPath,
+		Nonce:      new(big.Int).SetUint64(tx.Nonce()).Bytes(),
+		GasPrice:   tx.GasPrice().Bytes(),
+		GasLimit:   new(big.Int).SetUint64(tx.Gas()).Bytes(),
+		Value:      tx.Value().Bytes(),
+		DataLength: &length,
+	}
+	if to := tx.To(); to != nil {
+		request.To = (*to)[:] // Non contract deploy, set recipient explicitly
+	}
+	if length > 1024 { // Send the data chunked if that was requested
+		request.DataInitialChunk, data = data[:1024], data[1024:]
+	} else {
+		request.DataInitialChunk, data = data, nil
+	}
+	if chainID != nil { // EIP-155 transaction, set chain ID explicitly (only 32 bit is supported!?)
+		id := uint32(chainID.Int64())
+		request.ChainId = &id
+	}
+	// Send the initiation message and stream content until a signature is returned
+	response := new(trezor.EthereumTxRequest)
+	if _, err := w.trezorExchange(request, response); err != nil {
+		return common.Address{}, nil, err
+	}
+	for response.DataLength != nil && int(*response.DataLength) <= len(data) {
+		chunk := data[:*response.DataLength]
+		data = data[*response.DataLength:]
+
+		if _, err := w.trezorExchange(&trezor.EthereumTxAck{DataChunk: chunk}, response); err != nil {
+			return common.Address{}, nil, err
+		}
+	}
+	// Extract the Ethereum signature and do a sanity validation
+	if len(response.GetSignatureR()) == 0 || len(response.GetSignatureS()) == 0 || response.GetSignatureV() == 0 {
+		return common.Address{}, nil, errors.New("reply lacks signature")
+	}
+	signature := append(append(response.GetSignatureR(), response.GetSignatureS()...), byte(response.GetSignatureV()))
+
+	// Create the correct signer and signature transform based on the chain ID
+	var signer types.Signer
+	if chainID == nil {
+		signer = new(types.HomesteadSigner)
+	} else {
+		signer = types.NewEIP155Signer(chainID)
+		signature[64] = signature[64] - byte(chainID.Uint64()*2+35)
+	}
+	// Inject the final signature into the transaction and sanity check the sender
+	signed, err := tx.WithSignature(signer, signature)
+	if err != nil {
+		return common.Address{}, nil, err
+	}
+	sender, err := types.Sender(signer, signed)
+	if err != nil {
+		return common.Address{}, nil, err
+	}
+	return sender, signed, nil
+}
+
+// trezorExchange performs a data exchange with the Trezor wallet, sending it a
+// message and retrieving the response. If multiple responses are possible, the
+// method will also return the index of the destination object used.
+func (w *trezorDriver) trezorExchange(req proto.Message, results ...proto.Message) (int, error) {
+	// Construct the original message payload to chunk up
+	data, err := proto.Marshal(req)
+	if err != nil {
+		return 0, err
+	}
+	payload := make([]byte, 8+len(data))
+	copy(payload, []byte{0x23, 0x23})
+	binary.BigEndian.PutUint16(payload[2:], trezor.Type(req))
+	binary.BigEndian.PutUint32(payload[4:], uint32(len(data)))
+	copy(payload[8:], data)
+
+	// Stream all the chunks to the device
+	chunk := make([]byte, 64)
+	chunk[0] = 0x3f // Report ID magic number
+
+	for len(payload) > 0 {
+		// Construct the new message to stream, padding with zeroes if needed
+		if len(payload) > 63 {
+			copy(chunk[1:], payload[:63])
+			payload = payload[63:]
+		} else {
+			copy(chunk[1:], payload)
+			copy(chunk[1+len(payload):], make([]byte, 63-len(payload)))
+			payload = nil
+		}
+		// Send over to the device
+		w.log.Trace("Data chunk sent to the Trezor", "chunk", hexutil.Bytes(chunk))
+		if _, err := w.device.Write(chunk); err != nil {
+			return 0, err
+		}
+	}
+	// Stream the reply back from the wallet in 64 byte chunks
+	var (
+		kind  uint16
+		reply []byte
+	)
+	for {
+		// Read the next chunk from the Trezor wallet
+		if _, err := io.ReadFull(w.device, chunk); err != nil {
+			return 0, err
+		}
+		w.log.Trace("Data chunk received from the Trezor", "chunk", hexutil.Bytes(chunk))
+
+		// Make sure the transport header matches
+		if chunk[0] != 0x3f || (len(reply) == 0 && (chunk[1] != 0x23 || chunk[2] != 0x23)) {
+			return 0, errTrezorReplyInvalidHeader
+		}
+		// If it's the first chunk, retrieve the reply message type and total message length
+		var payload []byte
+
+		if len(reply) == 0 {
+			kind = binary.BigEndian.Uint16(chunk[3:5])
+			reply = make([]byte, 0, int(binary.BigEndian.Uint32(chunk[5:9])))
+			payload = chunk[9:]
+		} else {
+			payload = chunk[1:]
+		}
+		// Append to the reply and stop when filled up
+		if left := cap(reply) - len(reply); left > len(payload) {
+			reply = append(reply, payload...)
+		} else {
+			reply = append(reply, payload[:left]...)
+			break
+		}
+	}
+	// Try to parse the reply into the requested reply message
+	if kind == uint16(trezor.MessageType_MessageType_Failure) {
+		// Trezor returned a failure, extract and return the message
+		failure := new(trezor.Failure)
+		if err := proto.Unmarshal(reply, failure); err != nil {
+			return 0, err
+		}
+		return 0, errors.New("trezor: " + failure.GetMessage())
+	}
+	if kind == uint16(trezor.MessageType_MessageType_ButtonRequest) {
+		// Trezor is waiting for user confirmation, ack and wait for the next message
+		return w.trezorExchange(&trezor.ButtonAck{}, results...)
+	}
+	for i, res := range results {
+		if trezor.Type(res) == kind {
+			return i, proto.Unmarshal(reply, res)
+		}
+	}
+	expected := make([]string, len(results))
+	for i, res := range results {
+		expected[i] = trezor.Name(trezor.Type(res))
+	}
+	return 0, fmt.Errorf("trezor: expected reply types %s, got %s", expected, trezor.Name(kind))
+}
--- a/accounts/usbwallet/wallet.go
+++ b/accounts/usbwallet/wallet.go
@@ -0,0 +1,562 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// Package usbwallet implements support for USB hardware wallets.
+package usbwallet
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"math/big"
+	"sync"
+	"time"
+
+	ethereum "github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/karalabe/hid"
+)
+
+// Maximum time between wallet health checks to detect USB unplugs.
+const heartbeatCycle = time.Second
+
+// Minimum time to wait between self derivation attempts, even it the user is
+// requesting accounts like crazy.
+const selfDeriveThrottling = time.Second
+
+// driver defines the vendor specific functionality hardware wallets instances
+// must implement to allow using them with the wallet lifecycle management.
+type driver interface {
+	// Status returns a textual status to aid the user in the current state of the
+	// wallet. It also returns an error indicating any failure the wallet might have
+	// encountered.
+	Status() (string, error)
+
+	// Open initializes access to a wallet instance. The passphrase parameter may
+	// or may not be used by the implementation of a particular wallet instance.
+	Open(device io.ReadWriter, passphrase string) error
+
+	// Close releases any resources held by an open wallet instance.
+	Close() error
+
+	// Heartbeat performs a sanity check against the hardware wallet to see if it
+	// is still online and healthy.
+	Heartbeat() error
+
+	// Derive sends a derivation request to the USB device and returns the Ethereum
+	// address located on that path.
+	Derive(path accounts.DerivationPath) (common.Address, error)
+
+	// SignTx sends the transaction to the USB device and waits for the user to confirm
+	// or deny the transaction.
+	SignTx(path accounts.DerivationPath, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error)
+}
+
+// wallet represents the common functionality shared by all USB hardware
+// wallets to prevent reimplementing the same complex maintenance mechanisms
+// for different vendors.
+type wallet struct {
+	hub    *Hub          // USB hub scanning
+	driver driver        // Hardware implementation of the low level device operations
+	url    *accounts.URL // Textual URL uniquely identifying this wallet
+
+	info   hid.DeviceInfo // Known USB device infos about the wallet
+	device *hid.Device    // USB device advertising itself as a hardware wallet
+
+	accounts []accounts.Account                         // List of derive accounts pinned on the hardware wallet
+	paths    map[common.Address]accounts.DerivationPath // Known derivation paths for signing operations
+
+	deriveNextPath accounts.DerivationPath   // Next derivation path for account auto-discovery
+	deriveNextAddr common.Address            // Next derived account address for auto-discovery
+	deriveChain    ethereum.ChainStateReader // Blockchain state reader to discover used account with
+	deriveReq      chan chan struct{}        // Channel to request a self-derivation on
+	deriveQuit     chan chan error           // Channel to terminate the self-deriver with
+
+	healthQuit chan chan error
+
+	// Locking a hardware wallet is a bit special. Since hardware devices are lower
+	// performing, any communication with them might take a non negligible amount of
+	// time. Worse still, waiting for user confirmation can take arbitrarily long,
+	// but exclusive communication must be upheld during. Locking the entire wallet
+	// in the mean time however would stall any parts of the system that don't want
+	// to communicate, just read some state (e.g. list the accounts).
+	//
+	// As such, a hardware wallet needs two locks to function correctly. A state
+	// lock can be used to protect the wallet's software-side internal state, which
+	// must not be held exlusively during hardware communication. A communication
+	// lock can be used to achieve exclusive access to the device itself, this one
+	// however should allow "skipping" waiting for operations that might want to
+	// use the device, but can live without too (e.g. account self-derivation).
+	//
+	// Since we have two locks, it's important to know how to properly use them:
+	//   - Communication requires the `device` to not change, so obtaining the
+	//     commsLock should be done after having a stateLock.
+	//   - Communication must not disable read access to the wallet state, so it
+	//     must only ever hold a *read* lock to stateLock.
+	commsLock chan struct{} // Mutex (buf=1) for the USB comms without keeping the state locked
+	stateLock sync.RWMutex  // Protects read and write access to the wallet struct fields
+
+	log log.Logger // Contextual logger to tag the base with its id
+}
+
+// URL implements accounts.Wallet, returning the URL of the USB hardware device.
+func (w *wallet) URL() accounts.URL {
+	return *w.url // Immutable, no need for a lock
+}
+
+// Status implements accounts.Wallet, returning a custom status message from the
+// underlying vendor-specific hardware wallet implementation.
+func (w *wallet) Status() (string, error) {
+	w.stateLock.RLock() // No device communication, state lock is enough
+	defer w.stateLock.RUnlock()
+
+	status, failure := w.driver.Status()
+	if w.device == nil {
+		return "Closed", failure
+	}
+	return status, failure
+}
+
+// Open implements accounts.Wallet, attempting to open a USB connection to the
+// hardware wallet.
+func (w *wallet) Open(passphrase string) error {
+	w.stateLock.Lock() // State lock is enough since there's no connection yet at this point
+	defer w.stateLock.Unlock()
+
+	// If the device was already opened once, refuse to try again
+	if w.paths != nil {
+		return accounts.ErrWalletAlreadyOpen
+	}
+	// Make sure the actual device connection is done only once
+	if w.device == nil {
+		device, err := w.info.Open()
+		if err != nil {
+			return err
+		}
+		w.device = device
+		w.commsLock = make(chan struct{}, 1)
+		w.commsLock <- struct{}{} // Enable lock
+	}
+	// Delegate device initialization to the underlying driver
+	if err := w.driver.Open(w.device, passphrase); err != nil {
+		return err
+	}
+	// Connection successful, start life-cycle management
+	w.paths = make(map[common.Address]accounts.DerivationPath)
+
+	w.deriveReq = make(chan chan struct{})
+	w.deriveQuit = make(chan chan error)
+	w.healthQuit = make(chan chan error)
+
+	go w.heartbeat()
+	go w.selfDerive()
+
+	// Notify anyone listening for wallet events that a new device is accessible
+	go w.hub.updateFeed.Send(accounts.WalletEvent{Wallet: w, Kind: accounts.WalletOpened})
+
+	return nil
+}
+
+// heartbeat is a health check loop for the USB wallets to periodically verify
+// whether they are still present or if they malfunctioned.
+func (w *wallet) heartbeat() {
+	w.log.Debug("USB wallet health-check started")
+	defer w.log.Debug("USB wallet health-check stopped")
+
+	// Execute heartbeat checks until termination or error
+	var (
+		errc chan error
+		err  error
+	)
+	for errc == nil && err == nil {
+		// Wait until termination is requested or the heartbeat cycle arrives
+		select {
+		case errc = <-w.healthQuit:
+			// Termination requested
+			continue
+		case <-time.After(heartbeatCycle):
+			// Heartbeat time
+		}
+		// Execute a tiny data exchange to see responsiveness
+		w.stateLock.RLock()
+		if w.device == nil {
+			// Terminated while waiting for the lock
+			w.stateLock.RUnlock()
+			continue
+		}
+		<-w.commsLock // Don't lock state while resolving version
+		err = w.driver.Heartbeat()
+		w.commsLock <- struct{}{}
+		w.stateLock.RUnlock()
+
+		if err != nil {
+			w.stateLock.Lock() // Lock state to tear the wallet down
+			w.close()
+			w.stateLock.Unlock()
+		}
+		// Ignore non hardware related errors
+		err = nil
+	}
+	// In case of error, wait for termination
+	if err != nil {
+		w.log.Debug("USB wallet health-check failed", "err", err)
+		errc = <-w.healthQuit
+	}
+	errc <- err
+}
+
+// Close implements accounts.Wallet, closing the USB connection to the device.
+func (w *wallet) Close() error {
+	// Ensure the wallet was opened
+	w.stateLock.RLock()
+	hQuit, dQuit := w.healthQuit, w.deriveQuit
+	w.stateLock.RUnlock()
+
+	// Terminate the health checks
+	var herr error
+	if hQuit != nil {
+		errc := make(chan error)
+		hQuit <- errc
+		herr = <-errc // Save for later, we *must* close the USB
+	}
+	// Terminate the self-derivations
+	var derr error
+	if dQuit != nil {
+		errc := make(chan error)
+		dQuit <- errc
+		derr = <-errc // Save for later, we *must* close the USB
+	}
+	// Terminate the device connection
+	w.stateLock.Lock()
+	defer w.stateLock.Unlock()
+
+	w.healthQuit = nil
+	w.deriveQuit = nil
+	w.deriveReq = nil
+
+	if err := w.close(); err != nil {
+		return err
+	}
+	if herr != nil {
+		return herr
+	}
+	return derr
+}
+
+// close is the internal wallet closer that terminates the USB connection and
+// resets all the fields to their defaults.
+//
+// Note, close assumes the state lock is held!
+func (w *wallet) close() error {
+	// Allow duplicate closes, especially for health-check failures
+	if w.device == nil {
+		return nil
+	}
+	// Close the device, clear everything, then return
+	w.device.Close()
+	w.device = nil
+
+	w.accounts, w.paths = nil, nil
+	w.driver.Close()
+
+	return nil
+}
+
+// Accounts implements accounts.Wallet, returning the list of accounts pinned to
+// the USB hardware wallet. If self-derivation was enabled, the account list is
+// periodically expanded based on current chain state.
+func (w *wallet) Accounts() []accounts.Account {
+	// Attempt self-derivation if it's running
+	reqc := make(chan struct{}, 1)
+	select {
+	case w.deriveReq <- reqc:
+		// Self-derivation request accepted, wait for it
+		<-reqc
+	default:
+		// Self-derivation offline, throttled or busy, skip
+	}
+	// Return whatever account list we ended up with
+	w.stateLock.RLock()
+	defer w.stateLock.RUnlock()
+
+	cpy := make([]accounts.Account, len(w.accounts))
+	copy(cpy, w.accounts)
+	return cpy
+}
+
+// selfDerive is an account derivation loop that upon request attempts to find
+// new non-zero accounts.
+func (w *wallet) selfDerive() {
+	w.log.Debug("USB wallet self-derivation started")
+	defer w.log.Debug("USB wallet self-derivation stopped")
+
+	// Execute self-derivations until termination or error
+	var (
+		reqc chan struct{}
+		errc chan error
+		err  error
+	)
+	for errc == nil && err == nil {
+		// Wait until either derivation or termination is requested
+		select {
+		case errc = <-w.deriveQuit:
+			// Termination requested
+			continue
+		case reqc = <-w.deriveReq:
+			// Account discovery requested
+		}
+		// Derivation needs a chain and device access, skip if either unavailable
+		w.stateLock.RLock()
+		if w.device == nil || w.deriveChain == nil {
+			w.stateLock.RUnlock()
+			reqc <- struct{}{}
+			continue
+		}
+		select {
+		case <-w.commsLock:
+		default:
+			w.stateLock.RUnlock()
+			reqc <- struct{}{}
+			continue
+		}
+		// Device lock obtained, derive the next batch of accounts
+		var (
+			accs  []accounts.Account
+			paths []accounts.DerivationPath
+
+			nextAddr = w.deriveNextAddr
+			nextPath = w.deriveNextPath
+
+			context = context.Background()
+		)
+		for empty := false; !empty; {
+			// Retrieve the next derived Ethereum account
+			if nextAddr == (common.Address{}) {
+				if nextAddr, err = w.driver.Derive(nextPath); err != nil {
+					w.log.Warn("USB wallet account derivation failed", "err", err)
+					break
+				}
+			}
+			// Check the account's status against the current chain state
+			var (
+				balance *big.Int
+				nonce   uint64
+			)
+			balance, err = w.deriveChain.BalanceAt(context, nextAddr, nil)
+			if err != nil {
+				w.log.Warn("USB wallet balance retrieval failed", "err", err)
+				break
+			}
+			nonce, err = w.deriveChain.NonceAt(context, nextAddr, nil)
+			if err != nil {
+				w.log.Warn("USB wallet nonce retrieval failed", "err", err)
+				break
+			}
+			// If the next account is empty, stop self-derivation, but add it nonetheless
+			if balance.Sign() == 0 && nonce == 0 {
+				empty = true
+			}
+			// We've just self-derived a new account, start tracking it locally
+			path := make(accounts.DerivationPath, len(nextPath))
+			copy(path[:], nextPath[:])
+			paths = append(paths, path)
+
+			account := accounts.Account{
+				Address: nextAddr,
+				URL:     accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)},
+			}
+			accs = append(accs, account)
+
+			// Display a log message to the user for new (or previously empty accounts)
+			if _, known := w.paths[nextAddr]; !known || (!empty && nextAddr == w.deriveNextAddr) {
+				w.log.Info("USB wallet discovered new account", "address", nextAddr, "path", path, "balance", balance, "nonce", nonce)
+			}
+			// Fetch the next potential account
+			if !empty {
+				nextAddr = common.Address{}
+				nextPath[len(nextPath)-1]++
+			}
+		}
+		// Self derivation complete, release device lock
+		w.commsLock <- struct{}{}
+		w.stateLock.RUnlock()
+
+		// Insert any accounts successfully derived
+		w.stateLock.Lock()
+		for i := 0; i < len(accs); i++ {
+			if _, ok := w.paths[accs[i].Address]; !ok {
+				w.accounts = append(w.accounts, accs[i])
+				w.paths[accs[i].Address] = paths[i]
+			}
+		}
+		// Shift the self-derivation forward
+		// TODO(karalabe): don't overwrite changes from wallet.SelfDerive
+		w.deriveNextAddr = nextAddr
+		w.deriveNextPath = nextPath
+		w.stateLock.Unlock()
+
+		// Notify the user of termination and loop after a bit of time (to avoid trashing)
+		reqc <- struct{}{}
+		if err == nil {
+			select {
+			case errc = <-w.deriveQuit:
+				// Termination requested, abort
+			case <-time.After(selfDeriveThrottling):
+				// Waited enough, willing to self-derive again
+			}
+		}
+	}
+	// In case of error, wait for termination
+	if err != nil {
+		w.log.Debug("USB wallet self-derivation failed", "err", err)
+		errc = <-w.deriveQuit
+	}
+	errc <- err
+}
+
+// Contains implements accounts.Wallet, returning whether a particular account is
+// or is not pinned into this wallet instance. Although we could attempt to resolve
+// unpinned accounts, that would be an non-negligible hardware operation.
+func (w *wallet) Contains(account accounts.Account) bool {
+	w.stateLock.RLock()
+	defer w.stateLock.RUnlock()
+
+	_, exists := w.paths[account.Address]
+	return exists
+}
+
+// Derive implements accounts.Wallet, deriving a new account at the specific
+// derivation path. If pin is set to true, the account will be added to the list
+// of tracked accounts.
+func (w *wallet) Derive(path accounts.DerivationPath, pin bool) (accounts.Account, error) {
+	// Try to derive the actual account and update its URL if successful
+	w.stateLock.RLock() // Avoid device disappearing during derivation
+
+	if w.device == nil {
+		w.stateLock.RUnlock()
+		return accounts.Account{}, accounts.ErrWalletClosed
+	}
+	<-w.commsLock // Avoid concurrent hardware access
+	address, err := w.driver.Derive(path)
+	w.commsLock <- struct{}{}
+
+	w.stateLock.RUnlock()
+
+	// If an error occurred or no pinning was requested, return
+	if err != nil {
+		return accounts.Account{}, err
+	}
+	account := accounts.Account{
+		Address: address,
+		URL:     accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)},
+	}
+	if !pin {
+		return account, nil
+	}
+	// Pinning needs to modify the state
+	w.stateLock.Lock()
+	defer w.stateLock.Unlock()
+
+	if _, ok := w.paths[address]; !ok {
+		w.accounts = append(w.accounts, account)
+		w.paths[address] = path
+	}
+	return account, nil
+}
+
+// SelfDerive implements accounts.Wallet, trying to discover accounts that the
+// user used previously (based on the chain state), but ones that he/she did not
+// explicitly pin to the wallet manually. To avoid chain head monitoring, self
+// derivation only runs during account listing (and even then throttled).
+func (w *wallet) SelfDerive(base accounts.DerivationPath, chain ethereum.ChainStateReader) {
+	w.stateLock.Lock()
+	defer w.stateLock.Unlock()
+
+	w.deriveNextPath = make(accounts.DerivationPath, len(base))
+	copy(w.deriveNextPath[:], base[:])
+
+	w.deriveNextAddr = common.Address{}
+	w.deriveChain = chain
+}
+
+// SignHash implements accounts.Wallet, however signing arbitrary data is not
+// supported for hardware wallets, so this method will always return an error.
+func (w *wallet) SignHash(account accounts.Account, hash []byte) ([]byte, error) {
+	return nil, accounts.ErrNotSupported
+}
+
+// SignTx implements accounts.Wallet. It sends the transaction over to the Ledger
+// wallet to request a confirmation from the user. It returns either the signed
+// transaction or a failure if the user denied the transaction.
+//
+// Note, if the version of the Ethereum application running on the Ledger wallet is
+// too old to sign EIP-155 transactions, but such is requested nonetheless, an error
+// will be returned opposed to silently signing in Homestead mode.
+func (w *wallet) SignTx(account accounts.Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
+	w.stateLock.RLock() // Comms have own mutex, this is for the state fields
+	defer w.stateLock.RUnlock()
+
+	// If the wallet is closed, abort
+	if w.device == nil {
+		return nil, accounts.ErrWalletClosed
+	}
+	// Make sure the requested account is contained within
+	path, ok := w.paths[account.Address]
+	if !ok {
+		return nil, accounts.ErrUnknownAccount
+	}
+	// All infos gathered and metadata checks out, request signing
+	<-w.commsLock
+	defer func() { w.commsLock <- struct{}{} }()
+
+	// Ensure the device isn't screwed with while user confirmation is pending
+	// TODO(karalabe): remove if hotplug lands on Windows
+	w.hub.commsLock.Lock()
+	w.hub.commsPend++
+	w.hub.commsLock.Unlock()
+
+	defer func() {
+		w.hub.commsLock.Lock()
+		w.hub.commsPend--
+		w.hub.commsLock.Unlock()
+	}()
+	// Sign the transaction and verify the sender to avoid hardware fault surprises
+	sender, signed, err := w.driver.SignTx(path, tx, chainID)
+	if err != nil {
+		return nil, err
+	}
+	if sender != account.Address {
+		return nil, fmt.Errorf("signer mismatch: expected %s, got %s", account.Address.Hex(), sender.Hex())
+	}
+	return signed, nil
+}
+
+// SignHashWithPassphrase implements accounts.Wallet, however signing arbitrary
+// data is not supported for Ledger wallets, so this method will always return
+// an error.
+func (w *wallet) SignHashWithPassphrase(account accounts.Account, passphrase string, hash []byte) ([]byte, error) {
+	return w.SignHash(account, hash)
+}
+
+// SignTxWithPassphrase implements accounts.Wallet, attempting to sign the given
+// transaction with the given account using passphrase as extra authentication.
+// Since USB wallets don't rely on passphrases, these are silently ignored.
+func (w *wallet) SignTxWithPassphrase(account accounts.Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
+	return w.SignTx(account, tx, chainID)
+}
--- a/accounts/watch.go
+++ b/accounts/watch.go
@@ -1,113 +0,0 @@
-// Copyright 2016 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-// +build darwin,!ios freebsd linux,!arm64 netbsd solaris windows
-
-package accounts
-
-import (
-	"time"
-
-	"github.com/ethereum/go-ethereum/logger"
-	"github.com/ethereum/go-ethereum/logger/glog"
-	"github.com/rjeczalik/notify"
-)
-
-type watcher struct {
-	ac       *addrCache
-	starting bool
-	running  bool
-	ev       chan notify.EventInfo
-	quit     chan struct{}
-}
-
-func newWatcher(ac *addrCache) *watcher {
-	return &watcher{
-		ac:   ac,
-		ev:   make(chan notify.EventInfo, 10),
-		quit: make(chan struct{}),
-	}
-}
-
-// starts the watcher loop in the background.
-// Start a watcher in the background if that's not already in progress.
-// The caller must hold w.ac.mu.
-func (w *watcher) start() {
-	if w.starting || w.running {
-		return
-	}
-	w.starting = true
-	go w.loop()
-}
-
-func (w *watcher) close() {
-	close(w.quit)
-}
-
-func (w *watcher) loop() {
-	defer func() {
-		w.ac.mu.Lock()
-		w.running = false
-		w.starting = false
-		w.ac.mu.Unlock()
-	}()
-
-	err := notify.Watch(w.ac.keydir, w.ev, notify.All)
-	if err != nil {
-		glog.V(logger.Detail).Infof("can't watch %s: %v", w.ac.keydir, err)
-		return
-	}
-	defer notify.Stop(w.ev)
-	glog.V(logger.Detail).Infof("now watching %s", w.ac.keydir)
-	defer glog.V(logger.Detail).Infof("no longer watching %s", w.ac.keydir)
-
-	w.ac.mu.Lock()
-	w.running = true
-	w.ac.mu.Unlock()
-
-	// Wait for file system events and reload.
-	// When an event occurs, the reload call is delayed a bit so that
-	// multiple events arriving quickly only cause a single reload.
-	var (
-		debounce          = time.NewTimer(0)
-		debounceDuration  = 500 * time.Millisecond
-		inCycle, hadEvent bool
-	)
-	defer debounce.Stop()
-	for {
-		select {
-		case <-w.quit:
-			return
-		case <-w.ev:
-			if !inCycle {
-				debounce.Reset(debounceDuration)
-				inCycle = true
-			} else {
-				hadEvent = true
-			}
-		case <-debounce.C:
-			w.ac.mu.Lock()
-			w.ac.reload()
-			w.ac.mu.Unlock()
-			if hadEvent {
-				debounce.Reset(debounceDuration)
-				inCycle, hadEvent = true, false
-			} else {
-				inCycle, hadEvent = false, false
-			}
-		}
-	}
-}
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -21,20 +21,20 @@ environment:
      PATH: C:\msys64\mingw32\bin\;C:\Program Files (x86)\NSIS\;%PATH%

 install:
+  - git submodule update --init
  - rmdir C:\go /s /q
-  - appveyor DownloadFile https://storage.googleapis.com/golang/go1.7.3.windows-amd64.zip
-  - 7z x go1.7.3.windows-amd64.zip -y -oC:\ > NUL
+  - appveyor DownloadFile https://storage.googleapis.com/golang/go1.9.2.windows-%GETH_ARCH%.zip
+  - 7z x go1.9.2.windows-%GETH_ARCH%.zip -y -oC:\ > NUL
  - go version
  - gcc --version

 build_script:
-  - go run build\ci.go install -arch %GETH_ARCH%
+  - go run build\ci.go install

 after_build:
-  - go run build\ci.go archive -arch %GETH_ARCH% -type zip -signer WINDOWS_SIGNING_KEY -upload gethstore/builds
-  - go run build\ci.go nsis -arch %GETH_ARCH% -signer WINDOWS_SIGNING_KEY -upload gethstore/builds
+  - go run build\ci.go archive -type zip -signer WINDOWS_SIGNING_KEY -upload gethstore/builds
+  - go run build\ci.go nsis -signer WINDOWS_SIGNING_KEY -upload gethstore/builds

 test_script:
-  - set GOARCH=%GETH_ARCH%
  - set CGO_ENABLED=1
-  - go run build\ci.go test -vet -coverage
+  - go run build\ci.go test -coverage
--- a/bmt/bmt.go
+++ b/bmt/bmt.go
@@ -0,0 +1,561 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// Package bmt provides a binary merkle tree implementation
+package bmt
+
+import (
+	"fmt"
+	"hash"
+	"io"
+	"strings"
+	"sync"
+	"sync/atomic"
+)
+
+/*
+Binary Merkle Tree Hash is a hash function over arbitrary datachunks of limited size
+It is defined as the root hash of the binary merkle tree built over fixed size segments
+of the underlying chunk using any base hash function (e.g keccak 256 SHA3)
+
+It is used as the chunk hash function in swarm which in turn is the basis for the
+128 branching swarm hash http://swarm-guide.readthedocs.io/en/latest/architecture.html#swarm-hash
+
+The BMT is optimal for providing compact inclusion proofs, i.e. prove that a
+segment is a substring of a chunk starting at a particular offset
+The size of the underlying segments is fixed at 32 bytes (called the resolution
+of the BMT hash), the EVM word size to optimize for on-chain BMT verification
+as well as the hash size optimal for inclusion proofs in the merkle tree of the swarm hash.
+
+Two implementations are provided:
+
+* RefHasher is optimized for code simplicity and meant as a reference implementation
+* Hasher is optimized for speed taking advantage of concurrency with minimalistic
+  control structure to coordinate the concurrent routines
+  It implements the ChunkHash interface as well as the go standard hash.Hash interface
+
+*/
+
+const (
+	// DefaultSegmentCount is the maximum number of segments of the underlying chunk
+	DefaultSegmentCount = 128 // Should be equal to storage.DefaultBranches
+	// DefaultPoolSize is the maximum number of bmt trees used by the hashers, i.e,
+	// the maximum number of concurrent BMT hashing operations performed by the same hasher
+	DefaultPoolSize = 8
+)
+
+// BaseHasher is a hash.Hash constructor function used for the base hash of the  BMT.
+type BaseHasher func() hash.Hash
+
+// Hasher a reusable hasher for fixed maximum size chunks representing a BMT
+// implements the hash.Hash interface
+// reuse pool of Tree-s for amortised memory allocation and resource control
+// supports order-agnostic concurrent segment writes
+// as well as sequential read and write
+// can not be called concurrently on more than one chunk
+// can be further appended after Sum
+// Reset gives back the Tree to the pool and guaranteed to leave
+// the tree and itself in a state reusable for hashing a new chunk
+type Hasher struct {
+	pool        *TreePool   // BMT resource pool
+	bmt         *Tree       // prebuilt BMT resource for flowcontrol and proofs
+	blocksize   int         // segment size (size of hash) also for hash.Hash
+	count       int         // segment count
+	size        int         // for hash.Hash same as hashsize
+	cur         int         // cursor position for righmost currently open chunk
+	segment     []byte      // the rightmost open segment (not complete)
+	depth       int         // index of last level
+	result      chan []byte // result channel
+	hash        []byte      // to record the result
+	max         int32       // max segments for SegmentWriter interface
+	blockLength []byte      // The block length that needes to be added in Sum
+}
+
+// New creates a reusable Hasher
+// implements the hash.Hash interface
+// pulls a new Tree from a resource pool for hashing each chunk
+func New(p *TreePool) *Hasher {
+	return &Hasher{
+		pool:      p,
+		depth:     depth(p.SegmentCount),
+		size:      p.SegmentSize,
+		blocksize: p.SegmentSize,
+		count:     p.SegmentCount,
+		result:    make(chan []byte),
+	}
+}
+
+// Node is a reuseable segment hasher representing a node in a BMT
+// it allows for continued writes after a Sum
+// and is left in completely reusable state after Reset
+type Node struct {
+	level, index int   // position of node for information/logging only
+	initial      bool  // first and last node
+	root         bool  // whether the node is root to a smaller BMT
+	isLeft       bool  // whether it is left side of the parent double segment
+	unbalanced   bool  // indicates if a node has only the left segment
+	parent       *Node // BMT connections
+	state        int32 // atomic increment impl concurrent boolean toggle
+	left, right  []byte
+}
+
+// NewNode constructor for segment hasher nodes in the BMT
+func NewNode(level, index int, parent *Node) *Node {
+	return &Node{
+		parent:  parent,
+		level:   level,
+		index:   index,
+		initial: index == 0,
+		isLeft:  index%2 == 0,
+	}
+}
+
+// TreePool provides a pool of Trees used as resources by Hasher
+// a Tree popped from the pool is guaranteed to have clean state
+// for hashing a new chunk
+// Hasher Reset releases the Tree to the pool
+type TreePool struct {
+	lock         sync.Mutex
+	c            chan *Tree
+	hasher       BaseHasher
+	SegmentSize  int
+	SegmentCount int
+	Capacity     int
+	count        int
+}
+
+// NewTreePool creates a Tree pool with hasher, segment size, segment count and capacity
+// on GetTree it reuses free Trees or creates a new one if size is not reached
+func NewTreePool(hasher BaseHasher, segmentCount, capacity int) *TreePool {
+	return &TreePool{
+		c:            make(chan *Tree, capacity),
+		hasher:       hasher,
+		SegmentSize:  hasher().Size(),
+		SegmentCount: segmentCount,
+		Capacity:     capacity,
+	}
+}
+
+// Drain drains the pool uptil it has no more than n resources
+func (self *TreePool) Drain(n int) {
+	self.lock.Lock()
+	defer self.lock.Unlock()
+	for len(self.c) > n {
+		<-self.c
+		self.count--
+	}
+}
+
+// Reserve is blocking until it returns an available Tree
+// it reuses free Trees or creates a new one if size is not reached
+func (self *TreePool) Reserve() *Tree {
+	self.lock.Lock()
+	defer self.lock.Unlock()
+	var t *Tree
+	if self.count == self.Capacity {
+		return <-self.c
+	}
+	select {
+	case t = <-self.c:
+	default:
+		t = NewTree(self.hasher, self.SegmentSize, self.SegmentCount)
+		self.count++
+	}
+	return t
+}
+
+// Release gives back a Tree to the pool.
+// This Tree is guaranteed to be in reusable state
+// does not need locking
+func (self *TreePool) Release(t *Tree) {
+	self.c <- t // can never fail but...
+}
+
+// Tree is a reusable control structure representing a BMT
+// organised in a binary tree
+// Hasher uses a TreePool to pick one for each chunk hash
+// the Tree is 'locked' while not in the pool
+type Tree struct {
+	leaves []*Node
+}
+
+// Draw draws the BMT (badly)
+func (self *Tree) Draw(hash []byte, d int) string {
+	var left, right []string
+	var anc []*Node
+	for i, n := range self.leaves {
+		left = append(left, fmt.Sprintf("%v", hashstr(n.left)))
+		if i%2 == 0 {
+			anc = append(anc, n.parent)
+		}
+		right = append(right, fmt.Sprintf("%v", hashstr(n.right)))
+	}
+	anc = self.leaves
+	var hashes [][]string
+	for l := 0; len(anc) > 0; l++ {
+		var nodes []*Node
+		hash := []string{""}
+		for i, n := range anc {
+			hash = append(hash, fmt.Sprintf("%v|%v", hashstr(n.left), hashstr(n.right)))
+			if i%2 == 0 && n.parent != nil {
+				nodes = append(nodes, n.parent)
+			}
+		}
+		hash = append(hash, "")
+		hashes = append(hashes, hash)
+		anc = nodes
+	}
+	hashes = append(hashes, []string{"", fmt.Sprintf("%v", hashstr(hash)), ""})
+	total := 60
+	del := "                             "
+	var rows []string
+	for i := len(hashes) - 1; i >= 0; i-- {
+		var textlen int
+		hash := hashes[i]
+		for _, s := range hash {
+			textlen += len(s)
+		}
+		if total < textlen {
+			total = textlen + len(hash)
+		}
+		delsize := (total - textlen) / (len(hash) - 1)
+		if delsize > len(del) {
+			delsize = len(del)
+		}
+		row := fmt.Sprintf("%v: %v", len(hashes)-i-1, strings.Join(hash, del[:delsize]))
+		rows = append(rows, row)
+
+	}
+	rows = append(rows, strings.Join(left, "  "))
+	rows = append(rows, strings.Join(right, "  "))
+	return strings.Join(rows, "\n") + "\n"
+}
+
+// NewTree initialises the Tree by building up the nodes of a BMT
+// segment size is stipulated to be the size of the hash
+// segmentCount needs to be positive integer and does not need to be
+// a power of two and can even be an odd number
+// segmentSize * segmentCount determines the maximum chunk size
+// hashed using the tree
+func NewTree(hasher BaseHasher, segmentSize, segmentCount int) *Tree {
+	n := NewNode(0, 0, nil)
+	n.root = true
+	prevlevel := []*Node{n}
+	// iterate over levels and creates 2^level nodes
+	level := 1
+	count := 2
+	for d := 1; d <= depth(segmentCount); d++ {
+		nodes := make([]*Node, count)
+		for i := 0; i < len(nodes); i++ {
+			parent := prevlevel[i/2]
+			t := NewNode(level, i, parent)
+			nodes[i] = t
+		}
+		prevlevel = nodes
+		level++
+		count *= 2
+	}
+	// the datanode level is the nodes on the last level where
+	return &Tree{
+		leaves: prevlevel,
+	}
+}
+
+// methods needed by hash.Hash
+
+// Size returns the size
+func (self *Hasher) Size() int {
+	return self.size
+}
+
+// BlockSize returns the block size
+func (self *Hasher) BlockSize() int {
+	return self.blocksize
+}
+
+// Sum returns the hash of the buffer
+// hash.Hash interface Sum method appends the byte slice to the underlying
+// data before it calculates and returns the hash of the chunk
+func (self *Hasher) Sum(b []byte) (r []byte) {
+	t := self.bmt
+	i := self.cur
+	n := t.leaves[i]
+	j := i
+	// must run strictly before all nodes calculate
+	// datanodes are guaranteed to have a parent
+	if len(self.segment) > self.size && i > 0 && n.parent != nil {
+		n = n.parent
+	} else {
+		i *= 2
+	}
+	d := self.finalise(n, i)
+	self.writeSegment(j, self.segment, d)
+	c := <-self.result
+	self.releaseTree()
+
+	// sha3(length + BMT(pure_chunk))
+	if self.blockLength == nil {
+		return c
+	}
+	res := self.pool.hasher()
+	res.Reset()
+	res.Write(self.blockLength)
+	res.Write(c)
+	return res.Sum(nil)
+}
+
+// Hasher implements the SwarmHash interface
+
+// Hash waits for the hasher result and returns it
+// caller must call this on a BMT Hasher being written to
+func (self *Hasher) Hash() []byte {
+	return <-self.result
+}
+
+// Hasher implements the io.Writer interface
+
+// Write fills the buffer to hash
+// with every full segment complete launches a hasher go routine
+// that shoots up the BMT
+func (self *Hasher) Write(b []byte) (int, error) {
+	l := len(b)
+	if l <= 0 {
+		return 0, nil
+	}
+	s := self.segment
+	i := self.cur
+	count := (self.count + 1) / 2
+	need := self.count*self.size - self.cur*2*self.size
+	size := self.size
+	if need > size {
+		size *= 2
+	}
+	if l < need {
+		need = l
+	}
+	// calculate missing bit to complete current open segment
+	rest := size - len(s)
+	if need < rest {
+		rest = need
+	}
+	s = append(s, b[:rest]...)
+	need -= rest
+	// read full segments and the last possibly partial segment
+	for need > 0 && i < count-1 {
+		// push all finished chunks we read
+		self.writeSegment(i, s, self.depth)
+		need -= size
+		if need < 0 {
+			size += need
+		}
+		s = b[rest : rest+size]
+		rest += size
+		i++
+	}
+	self.segment = s
+	self.cur = i
+	// otherwise, we can assume len(s) == 0, so all buffer is read and chunk is not yet full
+	return l, nil
+}
+
+// Hasher implements the io.ReaderFrom interface
+
+// ReadFrom reads from io.Reader and appends to the data to hash using Write
+// it reads so that chunk to hash is maximum length or reader reaches EOF
+// caller must Reset the hasher prior to call
+func (self *Hasher) ReadFrom(r io.Reader) (m int64, err error) {
+	bufsize := self.size*self.count - self.size*self.cur - len(self.segment)
+	buf := make([]byte, bufsize)
+	var read int
+	for {
+		var n int
+		n, err = r.Read(buf)
+		read += n
+		if err == io.EOF || read == len(buf) {
+			hash := self.Sum(buf[:n])
+			if read == len(buf) {
+				err = NewEOC(hash)
+			}
+			break
+		}
+		if err != nil {
+			break
+		}
+		n, err = self.Write(buf[:n])
+		if err != nil {
+			break
+		}
+	}
+	return int64(read), err
+}
+
+// Reset needs to be called before writing to the hasher
+func (self *Hasher) Reset() {
+	self.getTree()
+	self.blockLength = nil
+}
+
+// Hasher implements the SwarmHash interface
+
+// ResetWithLength needs to be called before writing to the hasher
+// the argument is supposed to be the byte slice binary representation of
+// the legth of the data subsumed under the hash
+func (self *Hasher) ResetWithLength(l []byte) {
+	self.Reset()
+	self.blockLength = l
+
+}
+
+// Release gives back the Tree to the pool whereby it unlocks
+// it resets tree, segment and index
+func (self *Hasher) releaseTree() {
+	if self.bmt != nil {
+		n := self.bmt.leaves[self.cur]
+		for ; n != nil; n = n.parent {
+			n.unbalanced = false
+			if n.parent != nil {
+				n.root = false
+			}
+		}
+		self.pool.Release(self.bmt)
+		self.bmt = nil
+
+	}
+	self.cur = 0
+	self.segment = nil
+}
+
+func (self *Hasher) writeSegment(i int, s []byte, d int) {
+	h := self.pool.hasher()
+	n := self.bmt.leaves[i]
+
+	if len(s) > self.size && n.parent != nil {
+		go func() {
+			h.Reset()
+			h.Write(s)
+			s = h.Sum(nil)
+
+			if n.root {
+				self.result <- s
+				return
+			}
+			self.run(n.parent, h, d, n.index, s)
+		}()
+		return
+	}
+	go self.run(n, h, d, i*2, s)
+}
+
+func (self *Hasher) run(n *Node, h hash.Hash, d int, i int, s []byte) {
+	isLeft := i%2 == 0
+	for {
+		if isLeft {
+			n.left = s
+		} else {
+			n.right = s
+		}
+		if !n.unbalanced && n.toggle() {
+			return
+		}
+		if !n.unbalanced || !isLeft || i == 0 && d == 0 {
+			h.Reset()
+			h.Write(n.left)
+			h.Write(n.right)
+			s = h.Sum(nil)
+
+		} else {
+			s = append(n.left, n.right...)
+		}
+
+		self.hash = s
+		if n.root {
+			self.result <- s
+			return
+		}
+
+		isLeft = n.isLeft
+		n = n.parent
+		i++
+	}
+}
+
+// getTree obtains a BMT resource by reserving one from the pool
+func (self *Hasher) getTree() *Tree {
+	if self.bmt != nil {
+		return self.bmt
+	}
+	t := self.pool.Reserve()
+	self.bmt = t
+	return t
+}
+
+// atomic bool toggle implementing a concurrent reusable 2-state object
+// atomic addint with %2 implements atomic bool toggle
+// it returns true if the toggler just put it in the active/waiting state
+func (self *Node) toggle() bool {
+	return atomic.AddInt32(&self.state, 1)%2 == 1
+}
+
+func hashstr(b []byte) string {
+	end := len(b)
+	if end > 4 {
+		end = 4
+	}
+	return fmt.Sprintf("%x", b[:end])
+}
+
+func depth(n int) (d int) {
+	for l := (n - 1) / 2; l > 0; l /= 2 {
+		d++
+	}
+	return d
+}
+
+// finalise is following the zigzags on the tree belonging
+// to the final datasegment
+func (self *Hasher) finalise(n *Node, i int) (d int) {
+	isLeft := i%2 == 0
+	for {
+		// when the final segment's path is going via left segments
+		// the incoming data is pushed to the parent upon pulling the left
+		// we do not need toogle the state since this condition is
+		// detectable
+		n.unbalanced = isLeft
+		n.right = nil
+		if n.initial {
+			n.root = true
+			return d
+		}
+		isLeft = n.isLeft
+		n = n.parent
+		d++
+	}
+}
+
+// EOC (end of chunk) implements the error interface
+type EOC struct {
+	Hash []byte // read the hash of the chunk off the error
+}
+
+// Error returns the error string
+func (self *EOC) Error() string {
+	return fmt.Sprintf("hasher limit reached, chunk hash: %x", self.Hash)
+}
+
+// NewEOC creates new end of chunk error with the hash
+func NewEOC(hash []byte) *EOC {
+	return &EOC{hash}
+}
--- a/bmt/bmt_r.go
+++ b/bmt/bmt_r.go
@@ -0,0 +1,85 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// simple nonconcurrent reference implementation for hashsize segment based
+// Binary Merkle tree hash on arbitrary but fixed maximum chunksize
+//
+// This implementation does not take advantage of any paralellisms and uses
+// far more memory than necessary, but it is easy to see that it is correct.
+// It can be used for generating test cases for optimized implementations.
+// see testBMTHasherCorrectness function in bmt_test.go
+package bmt
+
+import (
+	"hash"
+)
+
+// RefHasher is the non-optimized easy to read reference implementation of BMT
+type RefHasher struct {
+	span    int
+	section int
+	cap     int
+	h       hash.Hash
+}
+
+// NewRefHasher returns a new RefHasher
+func NewRefHasher(hasher BaseHasher, count int) *RefHasher {
+	h := hasher()
+	hashsize := h.Size()
+	maxsize := hashsize * count
+	c := 2
+	for ; c < count; c *= 2 {
+	}
+	if c > 2 {
+		c /= 2
+	}
+	return &RefHasher{
+		section: 2 * hashsize,
+		span:    c * hashsize,
+		cap:     maxsize,
+		h:       h,
+	}
+}
+
+// Hash returns the BMT hash of the byte slice
+// implements the SwarmHash interface
+func (rh *RefHasher) Hash(d []byte) []byte {
+	if len(d) > rh.cap {
+		d = d[:rh.cap]
+	}
+
+	return rh.hash(d, rh.span)
+}
+
+func (rh *RefHasher) hash(d []byte, s int) []byte {
+	l := len(d)
+	left := d
+	var right []byte
+	if l > rh.section {
+		for ; s >= l; s /= 2 {
+		}
+		left = rh.hash(d[:s], s)
+		right = d[s:]
+		if l-s > rh.section/2 {
+			right = rh.hash(right, s)
+		}
+	}
+	defer rh.h.Reset()
+	rh.h.Write(left)
+	rh.h.Write(right)
+	h := rh.h.Sum(nil)
+	return h
+}
--- a/Show More
+++ b/Show More
@@ -1 +1 @@
 .5.0
 .8.2