initial commit for eth-p2p integration

This commit is contained in:
zelig 2014-12-05 21:14:55 +00:00
parent 4082c8b61d
commit 47793b606c
3 changed files with 500 additions and 0 deletions

73
eth/error.go Normal file

@ -0,0 +1,73 @@
package eth
import (
"fmt"
// "github.com/ethereum/go-ethereum/logger"
)
const (
ErrMsgTooLarge = iota
ErrDecode
ErrInvalidMsgCode
ErrProtocolVersionMismatch
ErrNetworkIdMismatch
ErrGenesisBlockMismatch
ErrNoStatusMsg
ErrExtraStatusMsg
ErrInvalidBlock
)
var errorToString = map[int]string{
ErrMsgTooLarge: "Message too long",
ErrDecode: "Invalid message",
ErrInvalidMsgCode: "Invalid message code",
ErrProtocolVersionMismatch: "Protocol version mismatch",
ErrNetworkIdMismatch: "NetworkId mismatch",
ErrGenesisBlockMismatch: "Genesis block mismatch",
ErrNoStatusMsg: "No status message",
ErrExtraStatusMsg: "Extra status message",
ErrInvalidBlock: "Invalid block",
}
type protocolError struct {
Code int
fatal bool
message string
format string
params []interface{}
// size int
}
func newProtocolError(code int, format string, params ...interface{}) *protocolError {
return &protocolError{Code: code, format: format, params: params}
}
func ProtocolError(code int, format string, params ...interface{}) (err *protocolError) {
err = newProtocolError(code, format, params...)
// report(err)
if err.Fatal() {
logger.Errorln(err)
} else {
logger.Debugln(err)
}
return
}
func (self protocolError) Error() (message string) {
message = self.message
if message == "" {
message, ok := errorToString[self.Code]
if !ok {
panic("invalid error code")
}
if self.format != "" {
message += ": " + fmt.Sprintf(self.format, self.params...)
}
self.message = message
}
return
}
func (self *protocolError) Fatal() bool {
return self.fatal
}

294
eth/protocol.go Normal file

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package eth
import (
"bytes"
"math"
"math/big"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/ethutil"
ethlogger "github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/p2p"
)
var logger = ethlogger.NewLogger("SERV")
// ethProtocol represents the ethereum wire protocol
// instance is running on each peer
type ethProtocol struct {
eth backend
td *big.Int
peer *p2p.Peer
rw p2p.MsgReadWriter
}
// backend is the interface the ethereum protocol backend should implement
// used as an argument to EthProtocol
type backend interface {
GetTransactions() (txs []*types.Transaction)
AddTransactions(txs []*types.Transaction)
GetBlockHashes(hash []byte, amount uint32) (hashes [][]byte)
AddHash(hash []byte, peer *p2p.Peer) (more bool)
GetBlock(hash []byte) (block *types.Block)
AddBlock(td *big.Int, block *types.Block, peer *p2p.Peer) (fetchHashes bool, err error)
AddPeer(td *big.Int, currentBlock []byte, peer *p2p.Peer) (fetchHashes bool)
Status() (td *big.Int, currentBlock []byte, genesisBlock []byte)
}
const (
ProtocolVersion = 43
// 0x00 // PoC-1
// 0x01 // PoC-2
// 0x07 // PoC-3
// 0x09 // PoC-4
// 0x17 // PoC-5
// 0x1c // PoC-6
NetworkId = 0
ProtocolLength = uint64(8)
ProtocolMaxMsgSize = 10 * 1024 * 1024
blockHashesBatchSize = 256
)
// eth protocol message codes
const (
StatusMsg = iota
GetTxMsg // unused
TxMsg
GetBlockHashesMsg
BlockHashesMsg
GetBlocksMsg
BlocksMsg
NewBlockMsg
)
// message structs used for rlp decoding
type newBlockMsgData struct {
Block *types.Block
TD *big.Int
}
type getBlockHashesMsgData struct {
Hash []byte
Amount uint32
}
// main entrypoint, wrappers starting a server running the eth protocol
// use this constructor to attach the protocol (class) to server caps
func EthProtocol(eth backend) *p2p.Protocol {
return &p2p.Protocol{
Name: "eth",
Version: ProtocolVersion,
Length: ProtocolLength,
Run: func(peer *p2p.Peer, rw p2p.MsgReadWriter) error {
return runEthProtocol(eth, peer, rw)
},
}
}
func runEthProtocol(eth backend, peer *p2p.Peer, rw p2p.MsgReadWriter) (err error) {
self := &ethProtocol{
eth: eth,
rw: rw,
peer: peer,
}
err = self.handleStatus()
if err == nil {
go func() {
for {
err = self.handle()
if err != nil {
break
}
}
}()
}
return
}
func (self *ethProtocol) handle() error {
msg, err := self.rw.ReadMsg()
if err != nil {
return err
}
if msg.Size > ProtocolMaxMsgSize {
return ProtocolError(ErrMsgTooLarge, "%v > %v", msg.Size, ProtocolMaxMsgSize)
}
// make sure that the payload has been fully consumed
defer msg.Discard()
switch msg.Code {
case StatusMsg:
return ProtocolError(ErrExtraStatusMsg, "")
case GetTxMsg:
txs := self.eth.GetTransactions()
// TODO: rewrite using rlp flat
txsInterface := make([]interface{}, len(txs))
for i, tx := range txs {
txsInterface[i] = tx.RlpData()
}
return self.rw.EncodeMsg(TxMsg, txsInterface...)
case TxMsg:
var txs []*types.Transaction
if err := msg.Decode(&txs); err != nil {
return ProtocolError(ErrDecode, "%v", err)
}
self.eth.AddTransactions(txs)
case GetBlockHashesMsg:
var request getBlockHashesMsgData
if err := msg.Decode(&request); err != nil {
return ProtocolError(ErrDecode, "%v", err)
}
hashes := self.eth.GetBlockHashes(request.Hash, request.Amount)
return self.rw.EncodeMsg(BlockHashesMsg, ethutil.ByteSliceToInterface(hashes)...)
case BlockHashesMsg:
// TODO: redo using lazy decode , this way very inefficient on known chains
// s := rlp.NewListStream(msg.Payload, uint64(msg.Size))
var blockHashes [][]byte
if err := msg.Decode(&blockHashes); err != nil {
return ProtocolError(ErrDecode, "%v", err)
}
fetchMore := true
for _, hash := range blockHashes {
fetchMore = self.eth.AddHash(hash, self.peer)
if !fetchMore {
break
}
}
if fetchMore {
return self.FetchHashes(blockHashes[len(blockHashes)-1])
}
case GetBlocksMsg:
// Limit to max 300 blocks
var blockHashes [][]byte
if err := msg.Decode(&blockHashes); err != nil {
return ProtocolError(ErrDecode, "%v", err)
}
max := int(math.Min(float64(len(blockHashes)), 300.0))
var blocks []interface{}
for i, hash := range blockHashes {
if i >= max {
break
}
block := self.eth.GetBlock(hash)
if block != nil {
blocks = append(blocks, block.Value().Raw())
}
}
return self.rw.EncodeMsg(BlocksMsg, blocks...)
case BlocksMsg:
var blocks []*types.Block
if err := msg.Decode(&blocks); err != nil {
return ProtocolError(ErrDecode, "%v", err)
}
for _, block := range blocks {
fetchHashes, err := self.eth.AddBlock(nil, block, self.peer)
if err != nil {
return ProtocolError(ErrInvalidBlock, "%v", err)
}
if fetchHashes {
if err := self.FetchHashes(block.Hash()); err != nil {
return err
}
}
}
case NewBlockMsg:
var request newBlockMsgData
if err := msg.Decode(&request); err != nil {
return ProtocolError(ErrDecode, "%v", err)
}
var fetchHashes bool
// this should reset td and offer blockpool as candidate new peer?
if fetchHashes, err = self.eth.AddBlock(request.TD, request.Block, self.peer); err != nil {
return ProtocolError(ErrInvalidBlock, "%v", err)
}
if fetchHashes {
return self.FetchHashes(request.Block.Hash())
}
default:
return ProtocolError(ErrInvalidMsgCode, "%v", msg.Code)
}
return nil
}
type statusMsgData struct {
ProtocolVersion uint
NetworkId uint
TD *big.Int
CurrentBlock []byte
GenesisBlock []byte
}
func (self *ethProtocol) statusMsg() p2p.Msg {
td, currentBlock, genesisBlock := self.eth.Status()
return p2p.NewMsg(StatusMsg,
uint32(ProtocolVersion),
uint32(NetworkId),
td,
currentBlock,
genesisBlock,
)
}
func (self *ethProtocol) handleStatus() error {
// send precanned status message
if err := self.rw.WriteMsg(self.statusMsg()); err != nil {
return err
}
// read and handle remote status
msg, err := self.rw.ReadMsg()
if err != nil {
return err
}
if msg.Code != StatusMsg {
return ProtocolError(ErrNoStatusMsg, "first msg has code %x (!= %x)", msg.Code, StatusMsg)
}
if msg.Size > ProtocolMaxMsgSize {
return ProtocolError(ErrMsgTooLarge, "%v > %v", msg.Size, ProtocolMaxMsgSize)
}
var status statusMsgData
if err := msg.Decode(&status); err != nil {
return ProtocolError(ErrDecode, "%v", err)
}
_, _, genesisBlock := self.eth.Status()
if bytes.Compare(status.GenesisBlock, genesisBlock) != 0 {
return ProtocolError(ErrGenesisBlockMismatch, "%x (!= %x)", status.GenesisBlock, genesisBlock)
}
if status.NetworkId != NetworkId {
return ProtocolError(ErrNetworkIdMismatch, "%d (!= %d)", status.NetworkId, NetworkId)
}
if ProtocolVersion != status.ProtocolVersion {
return ProtocolError(ErrProtocolVersionMismatch, "%d (!= %d)", status.ProtocolVersion, ProtocolVersion)
}
logger.Infof("Peer is [eth] capable (%d/%d). TD = %v ~ %x", status.ProtocolVersion, status.NetworkId, status.CurrentBlock)
if self.eth.AddPeer(status.TD, status.CurrentBlock, self.peer) {
return self.FetchHashes(status.CurrentBlock)
}
return nil
}
func (self *ethProtocol) FetchHashes(from []byte) error {
logger.Debugf("Fetching hashes (%d) %x...\n", blockHashesBatchSize, from[0:4])
return self.rw.EncodeMsg(GetBlockHashesMsg, from, blockHashesBatchSize)
}

133
eth/protocol_test.go Normal file

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package eth
import (
"io"
"math/big"
"testing"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/p2p"
)
type testMsgReadWriter struct {
in chan p2p.Msg
out chan p2p.Msg
}
func (self *testMsgReadWriter) In(msg p2p.Msg) {
self.in <- msg
}
func (self *testMsgReadWriter) Out(msg p2p.Msg) {
self.in <- msg
}
func (self *testMsgReadWriter) WriteMsg(msg p2p.Msg) error {
self.out <- msg
return nil
}
func (self *testMsgReadWriter) EncodeMsg(code uint64, data ...interface{}) error {
return self.WriteMsg(p2p.NewMsg(code, data))
}
func (self *testMsgReadWriter) ReadMsg() (p2p.Msg, error) {
msg, ok := <-self.in
if !ok {
return msg, io.EOF
}
return msg, nil
}
func errorCheck(t *testing.T, expCode int, err error) {
perr, ok := err.(*protocolError)
if ok && perr != nil {
if code := perr.Code; code != expCode {
ok = false
}
}
if !ok {
t.Errorf("expected error code %v, got %v", ErrNoStatusMsg, err)
}
}
type TestBackend struct {
getTransactions func() []*types.Transaction
addTransactions func(txs []*types.Transaction)
getBlockHashes func(hash []byte, amount uint32) (hashes [][]byte)
addHash func(hash []byte, peer *p2p.Peer) (more bool)
getBlock func(hash []byte) *types.Block
addBlock func(td *big.Int, block *types.Block, peer *p2p.Peer) (fetchHashes bool, err error)
addPeer func(td *big.Int, currentBlock []byte, peer *p2p.Peer) (fetchHashes bool)
status func() (td *big.Int, currentBlock []byte, genesisBlock []byte)
}
func (self *TestBackend) GetTransactions() (txs []*types.Transaction) {
if self.getTransactions != nil {
txs = self.getTransactions()
}
return
}
func (self *TestBackend) AddTransactions(txs []*types.Transaction) {
if self.addTransactions != nil {
self.addTransactions(txs)
}
}
func (self *TestBackend) GetBlockHashes(hash []byte, amount uint32) (hashes [][]byte) {
if self.getBlockHashes != nil {
hashes = self.getBlockHashes(hash, amount)
}
return
}
func (self *TestBackend) AddHash(hash []byte, peer *p2p.Peer) (more bool) {
if self.addHash != nil {
more = self.addHash(hash, peer)
}
return
}
func (self *TestBackend) GetBlock(hash []byte) (block *types.Block) {
if self.getBlock != nil {
block = self.getBlock(hash)
}
return
}
func (self *TestBackend) AddBlock(td *big.Int, block *types.Block, peer *p2p.Peer) (fetchHashes bool, err error) {
if self.addBlock != nil {
fetchHashes, err = self.addBlock(td, block, peer)
}
return
}
func (self *TestBackend) AddPeer(td *big.Int, currentBlock []byte, peer *p2p.Peer) (fetchHashes bool) {
if self.addPeer != nil {
fetchHashes = self.addPeer(td, currentBlock, peer)
}
return
}
func (self *TestBackend) Status() (td *big.Int, currentBlock []byte, genesisBlock []byte) {
if self.status != nil {
td, currentBlock, genesisBlock = self.status()
}
return
}
func TestEth(t *testing.T) {
quit := make(chan bool)
rw := &testMsgReadWriter{make(chan p2p.Msg, 10), make(chan p2p.Msg, 10)}
testBackend := &TestBackend{}
var err error
go func() {
err = runEthProtocol(testBackend, nil, rw)
close(quit)
}()
statusMsg := p2p.NewMsg(4)
rw.In(statusMsg)
<-quit
errorCheck(t, ErrNoStatusMsg, err)
// read(t, remote, []byte("hello, world"), nil)
}