swarm/network: fix chunk integrity checks (#3665)

* swarm/network: integrity on incoming known chunks
* swarm/network: fix integrity check for incoming chunks
* swarm/storage: imrpoved integrity checking on chunks
* dbstore panics on corrupt chunk entry an prompts user to run cleandb
* memstore adds logging for garbage collection
* dbstore refactor item delete. correct partial deletes in Get
* cmd/swarm: added cleandb subcommand

cmd/swarm/cleandb.go

@@ -0,0 +1,39 @@
+// 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 main
+
+import (
+	"log"
+
+	"github.com/ethereum/go-ethereum/swarm/storage"
+	"gopkg.in/urfave/cli.v1"
+)
+
+func cleandb(ctx *cli.Context) {
+	args := ctx.Args()
+	if len(args) != 1 {
+		log.Fatal("need path to chunks database as the first and only argument")
+	}
+
+	chunkDbPath := args[0]
+	hash := storage.MakeHashFunc("SHA3")
+	dbStore, err := storage.NewDbStore(chunkDbPath, hash, 10000000, 0)
+	if err != nil {
+		log.Fatalf("cannot initialise dbstore: %v", err)
+	}
+	dbStore.Cleanup()
+}