// Copyright 2016 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
// This is a simple Whisper node. It could be used as a stand-alone bootstrap node.
// Also, could be used for different test and diagnostics purposes.
package main
import (
"bufio"
"crypto/ecdsa"
"crypto/sha1"
"crypto/sha256"
"crypto/sha512"
"encoding/binary"
"encoding/hex"
"flag"
"fmt"
"os"
"strconv"
"strings"
"time"
"github.com/ethereum/go-ethereum/cmd/utils"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/console"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/logger/glog"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/discover"
"github.com/ethereum/go-ethereum/p2p/nat"
"github.com/ethereum/go-ethereum/whisper/mailserver"
whisper "github.com/ethereum/go-ethereum/whisper/whisperv5"
"golang.org/x/crypto/pbkdf2"
)
const quitCommand = "~Q"
// singletons
var (
server *p2p.Server
shh *whisper.Whisper
done chan struct{}
mailServer mailserver.WMailServer
input = bufio.NewReader(os.Stdin)
)
// encryption
var (
symKey []byte
pub *ecdsa.PublicKey
asymKey *ecdsa.PrivateKey
nodeid *ecdsa.PrivateKey
topic whisper.TopicType
filterID uint32
msPassword string
)
// cmd arguments
var (
echoMode = flag.Bool("e", false, "echo mode: prints some arguments for diagnostics")
bootstrapMode = flag.Bool("b", false, "boostrap node: don't actively connect to peers, wait for incoming connections")
forwarderMode = flag.Bool("f", false, "forwarder mode: only forward messages, neither send nor decrypt messages")
mailServerMode = flag.Bool("s", false, "mail server mode: delivers expired messages on demand")
requestMail = flag.Bool("r", false, "request expired messages from the bootstrap server")
asymmetricMode = flag.Bool("a", false, "use asymmetric encryption")
testMode = flag.Bool("t", false, "use of predefined parameters for diagnostics")
generateKey = flag.Bool("k", false, "generate and show the private key")
argTTL = flag.Uint("ttl", 30, "time-to-live for messages in seconds")
argWorkTime = flag.Uint("work", 5, "work time in seconds")
argPoW = flag.Float64("pow", whisper.MinimumPoW, "PoW for normal messages in float format (e.g. 2.7)")
argServerPoW = flag.Float64("mspow", whisper.MinimumPoW, "PoW requirement for Mail Server request")
argIP = flag.String("ip", "", "IP address and port of this node (e.g. 127.0.0.1:30303)")
argSalt = flag.String("salt", "", "salt (for topic and key derivation)")
argPub = flag.String("pub", "", "public key for asymmetric encryption")
argDBPath = flag.String("dbpath", "", "path to the server's DB directory")
argIDFile = flag.String("idfile", "", "file name with node id (private key)")
argEnode = flag.String("boot", "", "bootstrap node you want to connect to (e.g. enode://e454......08d50@52.176.211.200:16428)")
argTopic = flag.String("topic", "", "topic in hexadecimal format (e.g. 70a4beef)")
)
func main() {
processArgs()
initialize()
run()
}
func processArgs() {
flag.Parse()
if len(*argIDFile) > 0 {
var err error
nodeid, err = crypto.LoadECDSA(*argIDFile)
if err != nil {
utils.Fatalf("Failed to load file [%s]: %s.", *argIDFile, err)
}
}
const enodePrefix = "enode://"
if len(*argEnode) > 0 {
if (*argEnode)[:len(enodePrefix)] != enodePrefix {
*argEnode = enodePrefix + *argEnode
}
}
if len(*argTopic) > 0 {
x, err := hex.DecodeString(*argTopic)
if err != nil {
utils.Fatalf("Failed to parse the topic: %s", err)
}
topic = whisper.BytesToTopic(x)
}
if *asymmetricMode && len(*argPub) > 0 {
pub = crypto.ToECDSAPub(common.FromHex(*argPub))
if !isKeyValid(pub) {
utils.Fatalf("invalid public key")
}
}
if *echoMode {
echo()
}
}
func echo() {
fmt.Printf("ttl = %d \n", *argTTL)
fmt.Printf("workTime = %d \n", *argWorkTime)
fmt.Printf("pow = %f \n", *argPoW)
fmt.Printf("mspow = %f \n", *argServerPoW)
fmt.Printf("ip = %s \n", *argIP)
fmt.Printf("salt = %s \n", *argSalt)
fmt.Printf("pub = %s \n", common.ToHex(crypto.FromECDSAPub(pub)))
fmt.Printf("idfile = %s \n", *argIDFile)
fmt.Printf("dbpath = %s \n", *argDBPath)
fmt.Printf("boot = %s \n", *argEnode)
}
func initialize() {
glog.SetV(logger.Warn)
glog.SetToStderr(true)
done = make(chan struct{})
var peers []*discover.Node
var err error
if *generateKey {
key, err := crypto.GenerateKey()
if err != nil {
utils.Fatalf("Failed to generate private key: %s", err)
}
k := hex.EncodeToString(crypto.FromECDSA(key))
fmt.Printf("Random private key: %s \n", k)
os.Exit(0)
}
if *testMode {
password := []byte("test password for symmetric encryption")
salt := []byte("test salt for symmetric encryption")
symKey = pbkdf2.Key(password, salt, 64, 32, sha256.New)
topic = whisper.TopicType{0xFF, 0xFF, 0xFF, 0xFF}
msPassword = "mail server test password"
}
if *bootstrapMode {
if len(*argIP) == 0 {
argIP = scanLineA("Please enter your IP and port (e.g. 127.0.0.1:30348): ")
}
} else {
if len(*argEnode) == 0 {
argEnode = scanLineA("Please enter the peer's enode: ")
}
peer := discover.MustParseNode(*argEnode)
peers = append(peers, peer)
}
if *mailServerMode {
if len(msPassword) == 0 {
msPassword, err = console.Stdin.PromptPassword("Please enter the Mail Server password: ")
if err != nil {
utils.Fatalf("Failed to read Mail Server password: %s", err)
}
}
shh = whisper.New()
shh.RegisterServer(&mailServer)
mailServer.Init(shh, *argDBPath, msPassword, *argServerPoW)
} else {
shh = whisper.New()
}
asymKey = shh.NewIdentity()
if nodeid == nil {
nodeid = shh.NewIdentity()
}
maxPeers := 80
if *bootstrapMode {
maxPeers = 800
}
server = &p2p.Server{
Config: p2p.Config{
PrivateKey: nodeid,
MaxPeers: maxPeers,
Name: common.MakeName("whisper-go", "5.0"),
Protocols: shh.Protocols(),
ListenAddr: *argIP,
NAT: nat.Any(),
BootstrapNodes: peers,
StaticNodes: peers,
TrustedNodes: peers,
},
}
}
func startServer() {
err := server.Start()
if err != nil {
utils.Fatalf("Failed to start Whisper peer: %s.", err)
}
fmt.Printf("my public key: %s \n", common.ToHex(crypto.FromECDSAPub(&asymKey.PublicKey)))
fmt.Println(server.NodeInfo().Enode)
if *bootstrapMode {
configureNode()
fmt.Println("Bootstrap Whisper node started")
} else {
fmt.Println("Whisper node started")
// first see if we can establish connection, then ask for user input
waitForConnection(true)
configureNode()
}
if !*forwarderMode {
fmt.Printf("Please type the message. To quit type: '%s'\n", quitCommand)
}
}
func isKeyValid(k *ecdsa.PublicKey) bool {
return k.X != nil && k.Y != nil
}
func configureNode() {
var err error
var p2pAccept bool
if *forwarderMode {
return
}
if *asymmetricMode {
if len(*argPub) == 0 {
s := scanLine("Please enter the peer's public key: ")
pub = crypto.ToECDSAPub(common.FromHex(s))
if !isKeyValid(pub) {
utils.Fatalf("Error: invalid public key")
}
}
}
if *requestMail {
p2pAccept = true
if len(msPassword) == 0 {
msPassword, err = console.Stdin.PromptPassword("Please enter the Mail Server password: ")
if err != nil {
utils.Fatalf("Failed to read Mail Server password: %s", err)
}
}
}
if !*asymmetricMode && !*forwarderMode && !*testMode {
pass, err := console.Stdin.PromptPassword("Please enter the password: ")
if err != nil {
utils.Fatalf("Failed to read passphrase: %v", err)
}
if len(*argSalt) == 0 {
argSalt = scanLineA("Please enter the salt: ")
}
symKey = pbkdf2.Key([]byte(pass), []byte(*argSalt), 65356, 32, sha256.New)
if len(*argTopic) == 0 {
generateTopic([]byte(pass), []byte(*argSalt))
}
}
if *mailServerMode {
if len(*argDBPath) == 0 {
argDBPath = scanLineA("Please enter the path to DB file: ")
}
}
filter := whisper.Filter{
KeySym: symKey,
KeyAsym: asymKey,
Topics: []whisper.TopicType{topic},
AcceptP2P: p2pAccept,
}
filterID = shh.Watch(&filter)
fmt.Printf("Filter is configured for the topic: %x \n", topic)
}
func generateTopic(password, salt []byte) {
const rounds = 4000
const size = 128
x1 := pbkdf2.Key(password, salt, rounds, size, sha512.New)
x2 := pbkdf2.Key(password, salt, rounds, size, sha1.New)
x3 := pbkdf2.Key(x1, x2, rounds, size, sha256.New)
for i := 0; i < size; i++ {
topic[i%whisper.TopicLength] ^= x3[i]
}
}
func waitForConnection(timeout bool) {
var cnt int
var connected bool
for !connected {
time.Sleep(time.Millisecond * 50)
connected = server.PeerCount() > 0
if timeout {
cnt++
if cnt > 1000 {
utils.Fatalf("Timeout expired, failed to connect")
}
}
}
fmt.Println("Connected to peer.")
}
func run() {
defer mailServer.Close()
startServer()
defer server.Stop()
shh.Start(nil)
defer shh.Stop()
if !*forwarderMode {
go messageLoop()
}
if *requestMail {
requestExpiredMessagesLoop()
} else {
sendLoop()
}
}
func sendLoop() {
for {
s := scanLine("")
if s == quitCommand {
fmt.Println("Quit command received")
close(done)
break
}
sendMsg([]byte(s))
if *asymmetricMode {
// print your own message for convenience,
// because in asymmetric mode it is impossible to decrypt it
hour, min, sec := time.Now().Clock()
from := crypto.PubkeyToAddress(asymKey.PublicKey)
fmt.Printf("\n%02d:%02d:%02d <%x>: %s\n", hour, min, sec, from, s)
}
}
}
func scanLine(prompt string) string {
if len(prompt) > 0 {
fmt.Print(prompt)
}
txt, err := input.ReadString('\n')
if err != nil {
utils.Fatalf("input error: %s", err)
}
txt = strings.TrimRight(txt, "\n\r")
return txt
}
func scanLineA(prompt string) *string {
s := scanLine(prompt)
return &s
}
func scanUint(prompt string) uint32 {
s := scanLine(prompt)
i, err := strconv.Atoi(s)
if err != nil {
utils.Fatalf("Fail to parse the lower time limit: %s", err)
}
return uint32(i)
}
func sendMsg(payload []byte) {
params := whisper.MessageParams{
Src: asymKey,
Dst: pub,
KeySym: symKey,
Payload: payload,
Topic: topic,
TTL: uint32(*argTTL),
PoW: *argPoW,
WorkTime: uint32(*argWorkTime),
}
msg := whisper.NewSentMessage(¶ms)
envelope, err := msg.Wrap(¶ms)
if err != nil {
fmt.Printf("failed to seal message: %v \n", err)
return
}
err = shh.Send(envelope)
if err != nil {
fmt.Printf("failed to send message: %v \n", err)
}
}
func messageLoop() {
f := shh.GetFilter(filterID)
if f == nil {
utils.Fatalf("filter is not installed")
}
ticker := time.NewTicker(time.Millisecond * 50)
for {
select {
case <-ticker.C:
messages := f.Retrieve()
for _, msg := range messages {
printMessageInfo(msg)
}
case <-done:
return
}
}
}
func printMessageInfo(msg *whisper.ReceivedMessage) {
timestamp := fmt.Sprintf("%d", msg.Sent) // unix timestamp for diagnostics
text := string(msg.Payload)
var address common.Address
if msg.Src != nil {
address = crypto.PubkeyToAddress(*msg.Src)
}
if whisper.IsPubKeyEqual(msg.Src, &asymKey.PublicKey) {
fmt.Printf("\n%s <%x>: %s\n", timestamp, address, text) // message from myself
} else {
fmt.Printf("\n%s [%x]: %s\n", timestamp, address, text) // message from a peer
}
}
func requestExpiredMessagesLoop() {
var key, peerID []byte
var timeLow, timeUpp uint32
var t string
var xt, empty whisper.TopicType
err := shh.AddSymKey(mailserver.MailServerKeyName, []byte(msPassword))
if err != nil {
utils.Fatalf("Failed to create symmetric key for mail request: %s", err)
}
key = shh.GetSymKey(mailserver.MailServerKeyName)
peerID = extractIdFromEnode(*argEnode)
shh.MarkPeerTrusted(peerID)
for {
timeLow = scanUint("Please enter the lower limit of the time range (unix timestamp): ")
timeUpp = scanUint("Please enter the upper limit of the time range (unix timestamp): ")
t = scanLine("Please enter the topic (hexadecimal): ")
if len(t) >= whisper.TopicLength*2 {
x, err := hex.DecodeString(t)
if err != nil {
utils.Fatalf("Failed to parse the topic: %s", err)
}
xt = whisper.BytesToTopic(x)
}
if timeUpp == 0 {
timeUpp = 0xFFFFFFFF
}
data := make([]byte, 8+whisper.TopicLength)
binary.BigEndian.PutUint32(data, timeLow)
binary.BigEndian.PutUint32(data[4:], timeUpp)
copy(data[8:], xt[:])
if xt == empty {
data = data[:8]
}
var params whisper.MessageParams
params.PoW = *argServerPoW
params.Payload = data
params.KeySym = key
params.Src = nodeid
params.WorkTime = 5
msg := whisper.NewSentMessage(¶ms)
env, err := msg.Wrap(¶ms)
if err != nil {
utils.Fatalf("Wrap failed: %s", err)
}
err = shh.RequestHistoricMessages(peerID, env)
if err != nil {
utils.Fatalf("Failed to send P2P message: %s", err)
}
time.Sleep(time.Second * 5)
}
}
func extractIdFromEnode(s string) []byte {
n, err := discover.ParseNode(s)
if err != nil {
utils.Fatalf("Failed to parse enode: %s", err)
return nil
}
return n.ID[:]
}
