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-rw-r--r--eth/protocol.go379
1 files changed, 379 insertions, 0 deletions
diff --git a/eth/protocol.go b/eth/protocol.go
new file mode 100644
index 000000000..b52c7db42
--- /dev/null
+++ b/eth/protocol.go
@@ -0,0 +1,379 @@
+package eth
+
+import (
+ "bytes"
+ "fmt"
+ "math/big"
+
+ "github.com/ethereum/go-ethereum/core/types"
+ "github.com/ethereum/go-ethereum/errs"
+ "github.com/ethereum/go-ethereum/ethutil"
+ "github.com/ethereum/go-ethereum/logger"
+ "github.com/ethereum/go-ethereum/p2p"
+ "github.com/ethereum/go-ethereum/rlp"
+)
+
+const (
+ ProtocolVersion = 56
+ NetworkId = 0
+ ProtocolLength = uint64(8)
+ ProtocolMaxMsgSize = 10 * 1024 * 1024
+ maxHashes = 256
+ maxBlocks = 64
+)
+
+// eth protocol message codes
+const (
+ StatusMsg = iota
+ GetTxMsg // unused
+ TxMsg
+ GetBlockHashesMsg
+ BlockHashesMsg
+ GetBlocksMsg
+ BlocksMsg
+ NewBlockMsg
+)
+
+const (
+ ErrMsgTooLarge = iota
+ ErrDecode
+ ErrInvalidMsgCode
+ ErrProtocolVersionMismatch
+ ErrNetworkIdMismatch
+ ErrGenesisBlockMismatch
+ ErrNoStatusMsg
+ ErrExtraStatusMsg
+)
+
+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",
+}
+
+// ethProtocol represents the ethereum wire protocol
+// instance is running on each peer
+type ethProtocol struct {
+ txPool txPool
+ chainManager chainManager
+ blockPool blockPool
+ peer *p2p.Peer
+ id string
+ rw p2p.MsgReadWriter
+ errors *errs.Errors
+}
+
+// backend is the interface the ethereum protocol backend should implement
+// used as an argument to EthProtocol
+type txPool interface {
+ AddTransactions([]*types.Transaction)
+ GetTransactions() types.Transactions
+}
+
+type chainManager interface {
+ GetBlockHashesFromHash(hash []byte, amount uint64) (hashes [][]byte)
+ GetBlock(hash []byte) (block *types.Block)
+ Status() (td *big.Int, currentBlock []byte, genesisBlock []byte)
+}
+
+type blockPool interface {
+ AddBlockHashes(next func() ([]byte, bool), peerId string)
+ AddBlock(block *types.Block, peerId string)
+ AddPeer(td *big.Int, currentBlock []byte, peerId string, requestHashes func([]byte) error, requestBlocks func([][]byte) error, peerError func(*errs.Error)) (best bool)
+ RemovePeer(peerId string)
+}
+
+// message structs used for rlp decoding
+type newBlockMsgData struct {
+ Block *types.Block
+ TD *big.Int
+}
+
+type getBlockHashesMsgData struct {
+ Hash []byte
+ Amount uint64
+}
+
+// main entrypoint, wrappers starting a server running the eth protocol
+// use this constructor to attach the protocol ("class") to server caps
+// the Dev p2p layer then runs the protocol instance on each peer
+func EthProtocol(txPool txPool, chainManager chainManager, blockPool blockPool) p2p.Protocol {
+ return p2p.Protocol{
+ Name: "eth",
+ Version: ProtocolVersion,
+ Length: ProtocolLength,
+ Run: func(peer *p2p.Peer, rw p2p.MsgReadWriter) error {
+ return runEthProtocol(txPool, chainManager, blockPool, peer, rw)
+ },
+ }
+}
+
+// the main loop that handles incoming messages
+// note RemovePeer in the post-disconnect hook
+func runEthProtocol(txPool txPool, chainManager chainManager, blockPool blockPool, peer *p2p.Peer, rw p2p.MsgReadWriter) (err error) {
+ id := peer.ID()
+ self := &ethProtocol{
+ txPool: txPool,
+ chainManager: chainManager,
+ blockPool: blockPool,
+ rw: rw,
+ peer: peer,
+ errors: &errs.Errors{
+ Package: "ETH",
+ Errors: errorToString,
+ },
+ id: fmt.Sprintf("%x", id[:8]),
+ }
+ err = self.handleStatus()
+ if err == nil {
+ self.propagateTxs()
+ for {
+ err = self.handle()
+ if err != nil {
+ self.blockPool.RemovePeer(self.id)
+ break
+ }
+ }
+ }
+ return
+}
+
+func (self *ethProtocol) handle() error {
+ msg, err := self.rw.ReadMsg()
+ if err != nil {
+ return err
+ }
+ if msg.Size > ProtocolMaxMsgSize {
+ return self.protoError(ErrMsgTooLarge, "%v > %v", msg.Size, ProtocolMaxMsgSize)
+ }
+ // make sure that the payload has been fully consumed
+ defer msg.Discard()
+
+ switch msg.Code {
+ case GetTxMsg: // ignore
+ case StatusMsg:
+ return self.protoError(ErrExtraStatusMsg, "")
+
+ case TxMsg:
+ // TODO: rework using lazy RLP stream
+ var txs []*types.Transaction
+ if err := msg.Decode(&txs); err != nil {
+ return self.protoError(ErrDecode, "msg %v: %v", msg, err)
+ }
+ for _, tx := range txs {
+ jsonlogger.LogJson(&logger.EthTxReceived{
+ TxHash: ethutil.Bytes2Hex(tx.Hash()),
+ RemoteId: self.peer.ID().String(),
+ })
+ }
+ self.txPool.AddTransactions(txs)
+
+ case GetBlockHashesMsg:
+ var request getBlockHashesMsgData
+ if err := msg.Decode(&request); err != nil {
+ return self.protoError(ErrDecode, "->msg %v: %v", msg, err)
+ }
+
+ if request.Amount > maxHashes {
+ request.Amount = maxHashes
+ }
+ hashes := self.chainManager.GetBlockHashesFromHash(request.Hash, request.Amount)
+ return p2p.EncodeMsg(self.rw, BlockHashesMsg, ethutil.ByteSliceToInterface(hashes)...)
+
+ case BlockHashesMsg:
+ msgStream := rlp.NewStream(msg.Payload)
+ if _, err := msgStream.List(); err != nil {
+ return err
+ }
+
+ var i int
+ iter := func() (hash []byte, ok bool) {
+ hash, err := msgStream.Bytes()
+ if err == rlp.EOL {
+ return nil, false
+ } else if err != nil {
+ self.protoError(ErrDecode, "msg %v: after %v hashes : %v", msg, i, err)
+ return nil, false
+ }
+ i++
+ return hash, true
+ }
+ self.blockPool.AddBlockHashes(iter, self.id)
+
+ case GetBlocksMsg:
+ msgStream := rlp.NewStream(msg.Payload)
+ if _, err := msgStream.List(); err != nil {
+ return err
+ }
+
+ var blocks []interface{}
+ var i int
+ for {
+ i++
+ var hash []byte
+ if err := msgStream.Decode(&hash); err != nil {
+ if err == rlp.EOL {
+ break
+ } else {
+ return self.protoError(ErrDecode, "msg %v: %v", msg, err)
+ }
+ }
+ block := self.chainManager.GetBlock(hash)
+ if block != nil {
+ blocks = append(blocks, block)
+ }
+ if i == maxBlocks {
+ break
+ }
+ }
+ return p2p.EncodeMsg(self.rw, BlocksMsg, blocks...)
+
+ case BlocksMsg:
+ msgStream := rlp.NewStream(msg.Payload)
+ if _, err := msgStream.List(); err != nil {
+ return err
+ }
+ for {
+ var block types.Block
+ if err := msgStream.Decode(&block); err != nil {
+ if err == rlp.EOL {
+ break
+ } else {
+ return self.protoError(ErrDecode, "msg %v: %v", msg, err)
+ }
+ }
+ self.blockPool.AddBlock(&block, self.id)
+ }
+
+ case NewBlockMsg:
+ var request newBlockMsgData
+ if err := msg.Decode(&request); err != nil {
+ return self.protoError(ErrDecode, "msg %v: %v", msg, err)
+ }
+ hash := request.Block.Hash()
+ fmt.Printf("received block: %x\n", hash)
+ _, chainHead, _ := self.chainManager.Status()
+
+ jsonlogger.LogJson(&logger.EthChainReceivedNewBlock{
+ BlockHash: ethutil.Bytes2Hex(hash),
+ BlockNumber: request.Block.Number(), // this surely must be zero
+ ChainHeadHash: ethutil.Bytes2Hex(chainHead),
+ BlockPrevHash: ethutil.Bytes2Hex(request.Block.ParentHash()),
+ RemoteId: self.peer.ID().String(),
+ })
+ // to simplify backend interface adding a new block
+ // uses AddPeer followed by AddBlock only if peer is the best peer
+ // (or selected as new best peer)
+ if self.blockPool.AddPeer(request.TD, hash, self.id, self.requestBlockHashes, self.requestBlocks, self.protoErrorDisconnect) {
+ self.blockPool.AddBlock(request.Block, self.id)
+ }
+
+ default:
+ return self.protoError(ErrInvalidMsgCode, "%v", msg.Code)
+ }
+ return nil
+}
+
+type statusMsgData struct {
+ ProtocolVersion uint32
+ NetworkId uint32
+ TD *big.Int
+ CurrentBlock []byte
+ GenesisBlock []byte
+}
+
+func (self *ethProtocol) statusMsg() p2p.Msg {
+ td, currentBlock, genesisBlock := self.chainManager.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 self.protoError(ErrNoStatusMsg, "first msg has code %x (!= %x)", msg.Code, StatusMsg)
+ }
+
+ if msg.Size > ProtocolMaxMsgSize {
+ return self.protoError(ErrMsgTooLarge, "%v > %v", msg.Size, ProtocolMaxMsgSize)
+ }
+
+ var status statusMsgData
+ if err := msg.Decode(&status); err != nil {
+ return self.protoError(ErrDecode, "msg %v: %v", msg, err)
+ }
+
+ _, _, genesisBlock := self.chainManager.Status()
+
+ if !bytes.Equal(status.GenesisBlock, genesisBlock) {
+ return self.protoError(ErrGenesisBlockMismatch, "%x (!= %x)", status.GenesisBlock, genesisBlock)
+ }
+
+ if status.NetworkId != NetworkId {
+ return self.protoError(ErrNetworkIdMismatch, "%d (!= %d)", status.NetworkId, NetworkId)
+ }
+
+ if ProtocolVersion != status.ProtocolVersion {
+ return self.protoError(ErrProtocolVersionMismatch, "%d (!= %d)", status.ProtocolVersion, ProtocolVersion)
+ }
+
+ self.peer.Infof("Peer is [eth] capable (%d/%d). TD=%v H=%x\n", status.ProtocolVersion, status.NetworkId, status.TD, status.CurrentBlock[:4])
+
+ self.blockPool.AddPeer(status.TD, status.CurrentBlock, self.id, self.requestBlockHashes, self.requestBlocks, self.protoErrorDisconnect)
+
+ return nil
+}
+
+func (self *ethProtocol) requestBlockHashes(from []byte) error {
+ self.peer.Debugf("fetching hashes (%d) %x...\n", maxHashes, from[0:4])
+ return p2p.EncodeMsg(self.rw, GetBlockHashesMsg, interface{}(from), uint64(maxHashes))
+}
+
+func (self *ethProtocol) requestBlocks(hashes [][]byte) error {
+ self.peer.Debugf("fetching %v blocks", len(hashes))
+ return p2p.EncodeMsg(self.rw, GetBlocksMsg, ethutil.ByteSliceToInterface(hashes)...)
+}
+
+func (self *ethProtocol) protoError(code int, format string, params ...interface{}) (err *errs.Error) {
+ err = self.errors.New(code, format, params...)
+ err.Log(self.peer.Logger)
+ return
+}
+
+func (self *ethProtocol) protoErrorDisconnect(err *errs.Error) {
+ err.Log(self.peer.Logger)
+ if err.Fatal() {
+ self.peer.Disconnect(p2p.DiscSubprotocolError)
+ }
+}
+
+func (self *ethProtocol) propagateTxs() {
+ transactions := self.txPool.GetTransactions()
+ iface := make([]interface{}, len(transactions))
+ for i, transaction := range transactions {
+ iface[i] = transaction
+ }
+
+ self.rw.WriteMsg(p2p.NewMsg(TxMsg, iface...))
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-01-04 20:11:32 +0800