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-rw-r--r--eth/protocol.go319
1 files changed, 319 insertions, 0 deletions
diff --git a/eth/protocol.go b/eth/protocol.go
new file mode 100644
index 000000000..963d41794
--- /dev/null
+++ b/eth/protocol.go
@@ -0,0 +1,319 @@
+package eth
+
+import (
+ "bytes"
+ "fmt"
+ "math"
+ "math/big"
+
+ "github.com/ethereum/go-ethereum/core/types"
+ "github.com/ethereum/go-ethereum/ethutil"
+ "github.com/ethereum/go-ethereum/p2p"
+ "github.com/ethereum/go-ethereum/rlp"
+)
+
+const (
+ ProtocolVersion = 49
+ NetworkId = 0
+ ProtocolLength = uint64(8)
+ ProtocolMaxMsgSize = 10 * 1024 * 1024
+)
+
+// eth protocol message codes
+const (
+ StatusMsg = iota
+ GetTxMsg // unused
+ TxMsg
+ GetBlockHashesMsg
+ BlockHashesMsg
+ GetBlocksMsg
+ BlocksMsg
+ NewBlockMsg
+)
+
+// 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
+}
+
+// backend is the interface the ethereum protocol backend should implement
+// used as an argument to EthProtocol
+type txPool interface {
+ AddTransactions([]*types.Transaction)
+}
+
+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(int, string, ...interface{})) (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) {
+ self := &ethProtocol{
+ txPool: txPool,
+ chainManager: chainManager,
+ blockPool: blockPool,
+ rw: rw,
+ peer: peer,
+ id: (string)(peer.Identity().Pubkey()),
+ }
+ err = self.handleStatus()
+ if err == nil {
+ for {
+ err = self.handle()
+ if err != nil {
+ fmt.Println(err)
+ 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 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 TxMsg:
+ // TODO: rework using lazy RLP stream
+ var txs []*types.Transaction
+ if err := msg.Decode(&txs); err != nil {
+ return ProtocolError(ErrDecode, "%v", err)
+ }
+ self.txPool.AddTransactions(txs)
+
+ case GetBlockHashesMsg:
+ var request getBlockHashesMsgData
+ if err := msg.Decode(&request); err != nil {
+ return ProtocolError(ErrDecode, "%v", err)
+ }
+ hashes := self.chainManager.GetBlockHashesFromHash(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
+ msgStream := rlp.NewListStream(msg.Payload, uint64(msg.Size))
+ var err error
+ iter := func() (hash []byte, ok bool) {
+ hash, err = msgStream.Bytes()
+ if err == nil {
+ ok = true
+ }
+ return
+ }
+ self.blockPool.AddBlockHashes(iter, self.id)
+ if err != nil && err != rlp.EOL {
+ return ProtocolError(ErrDecode, "%v", err)
+ }
+
+ case GetBlocksMsg:
+ var blockHashes [][]byte
+ if err := msg.Decode(&blockHashes); err != nil {
+ return ProtocolError(ErrDecode, "%v", err)
+ }
+ max := int(math.Min(float64(len(blockHashes)), blockHashesBatchSize))
+ var blocks []interface{}
+ for i, hash := range blockHashes {
+ if i >= max {
+ break
+ }
+ block := self.chainManager.GetBlock(hash)
+ if block != nil {
+ blocks = append(blocks, block.RlpData())
+ }
+ }
+ return self.rw.EncodeMsg(BlocksMsg, blocks...)
+
+ case BlocksMsg:
+ msgStream := rlp.NewListStream(msg.Payload, uint64(msg.Size))
+ for {
+ var block *types.Block
+ if err := msgStream.Decode(&block); err != nil {
+ if err == rlp.EOL {
+ break
+ } else {
+ return ProtocolError(ErrDecode, "%v", err)
+ }
+ }
+ self.blockPool.AddBlock(block, self.id)
+ }
+
+ case NewBlockMsg:
+ var request newBlockMsgData
+ if err := msg.Decode(&request); err != nil {
+ return ProtocolError(ErrDecode, "%v", err)
+ }
+ hash := request.Block.Hash()
+ // to simplify backend interface adding a new block
+ // uses AddPeer followed by AddHashes, 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) {
+ called := true
+ iter := func() (hash []byte, ok bool) {
+ if called {
+ called = false
+ return hash, true
+ } else {
+ return
+ }
+ }
+ self.blockPool.AddBlockHashes(iter, self.id)
+ self.blockPool.AddBlock(request.Block, self.id)
+ }
+
+ 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.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 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.chainManager.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)
+ }
+
+ 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)
+ self.peer.Infoln("AddPeer(IGNORED)")
+
+ return nil
+}
+
+func (self *ethProtocol) requestBlockHashes(from []byte) error {
+ self.peer.Debugf("fetching hashes (%d) %x...\n", blockHashesBatchSize, from[0:4])
+ return self.rw.EncodeMsg(GetBlockHashesMsg, from, blockHashesBatchSize)
+}
+
+func (self *ethProtocol) requestBlocks(hashes [][]byte) error {
+ self.peer.Debugf("fetching %v blocks", len(hashes))
+ return self.rw.EncodeMsg(GetBlocksMsg, ethutil.ByteSliceToInterface(hashes))
+}
+
+func (self *ethProtocol) protoError(code int, format string, params ...interface{}) (err *protocolError) {
+ err = ProtocolError(code, format, params...)
+ if err.Fatal() {
+ self.peer.Errorln(err)
+ } else {
+ self.peer.Debugln(err)
+ }
+ return
+}
+
+func (self *ethProtocol) protoErrorDisconnect(code int, format string, params ...interface{}) {
+ err := ProtocolError(code, format, params...)
+ if err.Fatal() {
+ self.peer.Errorln(err)
+ // disconnect
+ } else {
+ self.peer.Debugln(err)
+ }
+
+}
generated by cgit (git 2.34.1) at 2024-11-12 18:30:47 +0800