# Nimbus - Ethereum Wire Protocol, version eth/65 # # Copyright (c) 2018-2021 Status Research & Development GmbH # Licensed under either of # * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0) # * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT) # at your option. This file may not be copied, modified, or distributed except according to those terms. ## This module implements Ethereum Wire Protocol version 65, `eth/65`. ## Specification: ## https://github.com/ethereum/devp2p/blob/master/caps/eth.md import chronos, stint, chronicles, stew/byteutils, macros, eth/[common/eth_types, rlp, p2p], eth/p2p/[rlpx, private/p2p_types, blockchain_utils] type NewBlockHashesAnnounce* = object hash: KeccakHash number: uint64 # Note: Was `uint`, wrong on 32-bit targets. NewBlockAnnounce* = EthBlock ForkId* = object forkHash: array[4, byte] # The RLP encoding must be exactly 4 bytes. forkNext: BlockNumber # The RLP encoding must be variable-length PeerState = ref object initialized*: bool bestBlockHash*: KeccakHash bestDifficulty*: DifficultyInt const tracePackets* = true # Set `true` or `false` to control packet traces. traceHandshakes* = true const maxStateFetch* = 384 maxBodiesFetch* = 128 maxReceiptsFetch* = 256 maxHeadersFetch* = 192 ethVersion = 65 func toHex*(x: KeccakHash): string = x.data.toHex macro tracePacket*(msg: static[string], args: varargs[untyped]) = quote do: if tracePackets: trace `msg`, `args` p2pProtocol eth(version = ethVersion, peerState = PeerState, useRequestIds = false): onPeerConnected do (peer: Peer): let network = peer.network chain = network.chain bestBlock = chain.getBestBlockHeader chainForkId = chain.getForkId(bestBlock.blockNumber) forkId = ForkId( forkHash: chainForkId.crc.toBytesBe, forkNext: chainForkId.nextFork.u256, ) tracePacket ">> Sending eth.Status (0x00) [eth/" & $ethVersion & "]", peer, td=bestBlock.difficulty, bestHash=bestBlock.blockHash.toHex, networkId=network.networkId, genesis=chain.genesisHash.toHex, forkHash=forkId.forkHash.toHex, forkNext=forkId.forkNext let m = await peer.status(ethVersion, network.networkId, bestBlock.difficulty, bestBlock.blockHash, chain.genesisHash, forkId, timeout = chronos.seconds(10)) if traceHandshakes: trace "Handshake: Local and remote networkId", local=network.networkId, remote=m.networkId trace "Handshake: Local and remote genesisHash", local=chain.genesisHash.toHex, remote=m.genesisHash.toHex trace "Handshake: Local and remote forkId", local=(forkId.forkHash.toHex & "/" & $forkId.forkNext), remote=(m.forkId.forkHash.toHex & "/" & $m.forkId.forkNext) if m.networkId != network.networkId: trace "Peer for a different network (networkId)", peer, expectNetworkId=network.networkId, gotNetworkId=m.networkId raise newException(UselessPeerError, "Eth handshake for different network") if m.genesisHash != chain.genesisHash: trace "Peer for a different network (genesisHash)", peer, expectGenesis=chain.genesisHash.toHex, gotGenesis=m.genesisHash.toHex raise newException(UselessPeerError, "Eth handshake for different network") trace "Peer matches our network", peer peer.state.initialized = true peer.state.bestDifficulty = m.totalDifficulty peer.state.bestBlockHash = m.bestHash handshake: # User message 0x00: Status. proc status(peer: Peer, ethVersionArg: uint, networkId: NetworkId, totalDifficulty: DifficultyInt, bestHash: KeccakHash, genesisHash: KeccakHash, forkId: ForkId) = tracePacket "<< Received eth.Status (0x00) [eth/" & $ethVersion & "]", peer, td=totalDifficulty, bestHash=bestHash.toHex, networkId, genesis=genesisHash.toHex, forkHash=forkId.forkHash.toHex, forkNext=forkId.forkNext # User message 0x01: NewBlockHashes. proc newBlockHashes(peer: Peer, hashes: openArray[NewBlockHashesAnnounce]) = tracePacket "<< Discarding eth.NewBlockHashes (0x01)", peer, count=hashes.len discard # User message 0x02: Transactions. proc transactions(peer: Peer, transactions: openArray[Transaction]) = tracePacket "<< Discarding eth.Transactions (0x02)", peer, count=transactions.len discard requestResponse: # User message 0x03: GetBlockHeaders. proc getBlockHeaders(peer: Peer, request: BlocksRequest) = tracePacket "<< Received eth.GetBlockHeaders (0x03)", peer, count=request.maxResults if request.maxResults > uint64(maxHeadersFetch): debug "eth.GetBlockHeaders (0x03) requested too many headers", peer, requested=request.maxResults, max=maxHeadersFetch await peer.disconnect(BreachOfProtocol) return let headers = peer.network.chain.getBlockHeaders(request) if headers.len > 0: tracePacket ">> Replying with eth.BlockHeaders (0x04)", peer, count=headers.len else: tracePacket ">> Replying EMPTY eth.BlockHeaders (0x04)", peer, count=0 await response.send(headers) # User message 0x04: BlockHeaders. proc blockHeaders(p: Peer, headers: openArray[BlockHeader]) requestResponse: # User message 0x05: GetBlockBodies. proc getBlockBodies(peer: Peer, hashes: openArray[KeccakHash]) = tracePacket "<< Received eth.GetBlockBodies (0x05)", peer, count=hashes.len if hashes.len > maxBodiesFetch: debug "eth.GetBlockBodies (0x05) requested too many bodies", peer, requested=hashes.len, max=maxBodiesFetch await peer.disconnect(BreachOfProtocol) return let bodies = peer.network.chain.getBlockBodies(hashes) if bodies.len > 0: tracePacket ">> Replying with eth.BlockBodies (0x06)", peer, count=bodies.len else: tracePacket ">> Replying EMPTY eth.BlockBodies (0x06)", peer, count=0 await response.send(bodies) # User message 0x06: BlockBodies. proc blockBodies(peer: Peer, blocks: openArray[BlockBody]) # User message 0x07: NewBlock. proc newBlock(peer: Peer, bh: EthBlock, totalDifficulty: DifficultyInt) = # (Note, needs to use `EthBlock` instead of its alias `NewBlockAnnounce` # because either `p2pProtocol` or RLPx doesn't work with an alias.) tracePacket "<< Discarding eth.NewBlock (0x07)", peer, totalDifficulty, blockNumber=bh.header.blockNumber, blockDifficulty=bh.header.difficulty discard # User message 0x08: NewPooledTransactionHashes. proc newPooledTransactionHashes(peer: Peer, hashes: openArray[KeccakHash]) = tracePacket "<< Discarding eth.NewPooledTransactionHashes (0x08)", peer, count=hashes.len discard requestResponse: # User message 0x09: GetPooledTransactions. proc getPooledTransactions(peer: Peer, hashes: openArray[KeccakHash]) = tracePacket "<< Received eth.GetPooledTransactions (0x09)", peer, count=hashes.len tracePacket ">> Replying EMPTY eth.PooledTransactions (0x10)", peer, count=0 await response.send([]) # User message 0x0a: PooledTransactions. proc pooledTransactions(peer: Peer, transactions: openArray[Transaction]) nextId 0x0d requestResponse: # User message 0x0d: GetNodeData. proc getNodeData(peer: Peer, hashes: openArray[KeccakHash]) = tracePacket "<< Received eth.GetNodeData (0x0d)", peer, count=hashes.len let blobs = peer.network.chain.getStorageNodes(hashes) if blobs.len > 0: tracePacket ">> Replying with eth.NodeData (0x0e)", peer, count=blobs.len else: tracePacket ">> Replying EMPTY eth.NodeData (0x0e)", peer, count=0 await response.send(blobs) # User message 0x0e: NodeData. proc nodeData(peer: Peer, data: openArray[Blob]) requestResponse: # User message 0x0f: GetReceipts. proc getReceipts(peer: Peer, hashes: openArray[KeccakHash]) = tracePacket "<< Received eth.GetReceipts (0x0f)", peer, count=hashes.len tracePacket ">> Replying EMPTY eth.Receipts (0x10)", peer, count=0 await response.send([]) # TODO: implement `getReceipts` and reactivate this code # await response.send(peer.network.chain.getReceipts(hashes)) # User message 0x10: Receipts. proc receipts(peer: Peer, receipts: openArray[Receipt])