whisper: project restructured, version 5 introduced (#3022)

whisper: project restructured, version 5 introduced

This commits adds a draft version of the new shh v5 protocol.
The new version is not on by default, --shh still selects version 2.

whisper/whisperv2/main.go

@@ -0,0 +1,106 @@
+// 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/>.
+
+// +build none
+
+// Contains a simple whisper peer setup and self messaging to allow playing
+// around with the protocol and API without a fancy client implementation.
+
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/logger"
+	"github.com/ethereum/go-ethereum/p2p"
+	"github.com/ethereum/go-ethereum/p2p/nat"
+	"github.com/ethereum/go-ethereum/whisper"
+)
+
+func main() {
+	logger.AddLogSystem(logger.NewStdLogSystem(os.Stdout, log.LstdFlags, logger.InfoLevel))
+
+	// Generate the peer identity
+	key, err := crypto.GenerateKey()
+	if err != nil {
+		fmt.Printf("Failed to generate peer key: %v.\n", err)
+		os.Exit(-1)
+	}
+	name := common.MakeName("whisper-go", "1.0")
+	shh := whisper.New()
+
+	// Create an Ethereum peer to communicate through
+	server := p2p.Server{
+		PrivateKey: key,
+		MaxPeers:   10,
+		Name:       name,
+		Protocols:  []p2p.Protocol{shh.Protocol()},
+		ListenAddr: ":30300",
+		NAT:        nat.Any(),
+	}
+	fmt.Println("Starting Ethereum peer...")
+	if err := server.Start(); err != nil {
+		fmt.Printf("Failed to start Ethereum peer: %v.\n", err)
+		os.Exit(1)
+	}
+
+	// Send a message to self to check that something works
+	payload := fmt.Sprintf("Hello world, this is %v. In case you're wondering, the time is %v", name, time.Now())
+	if err := selfSend(shh, []byte(payload)); err != nil {
+		fmt.Printf("Failed to self message: %v.\n", err)
+		os.Exit(-1)
+	}
+}
+
+// SendSelf wraps a payload into a Whisper envelope and forwards it to itself.
+func selfSend(shh *whisper.Whisper, payload []byte) error {
+	ok := make(chan struct{})
+
+	// Start watching for self messages, output any arrivals
+	id := shh.NewIdentity()
+	shh.Watch(whisper.Filter{
+		To: &id.PublicKey,
+		Fn: func(msg *whisper.Message) {
+			fmt.Printf("Message received: %s, signed with 0x%x.\n", string(msg.Payload), msg.Signature)
+			close(ok)
+		},
+	})
+	// Wrap the payload and encrypt it
+	msg := whisper.NewMessage(payload)
+	envelope, err := msg.Wrap(whisper.DefaultPoW, whisper.Options{
+		From: id,
+		To:   &id.PublicKey,
+		TTL:  whisper.DefaultTTL,
+	})
+	if err != nil {
+		return fmt.Errorf("failed to seal message: %v", err)
+	}
+	// Dump the message into the system and wait for it to pop back out
+	if err := shh.Send(envelope); err != nil {
+		return fmt.Errorf("failed to send self-message: %v", err)
+	}
+	select {
+	case <-ok:
+	case <-time.After(time.Second):
+		return fmt.Errorf("failed to receive message in time")
+	}
+	return nil
+}