# Nimbus # Copyright (c) 2023 Status Research & Development GmbH # Licensed under either of # * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE)) # * MIT license ([LICENSE-MIT](LICENSE-MIT)) # at your option. # This file may not be copied, modified, or distributed except according to # those terms. import std/[typetraits], eth/common, stew/results, ../web3_eth_conv, ../beacon_engine, ../execution_types, ./api_utils, chronicles {.push gcsafe, raises:[CatchableError].} template validateVersion(attrsOpt, com) = if attrsOpt.isSome: let attr = attrsOpt.get version = attr.version timestamp = ethTime attr.timestamp if com.isCancunOrLater(timestamp): if version != Version.V3: raise invalidParams("if timestamp is Cancun or later," & " payloadAttributes must be PayloadAttributesV3") elif com.isShanghaiOrLater(timestamp): if version != Version.V2: raise invalidParams("if timestamp is Shanghai or later," & " payloadAttributes must be PayloadAttributesV2") else: if version != Version.V1: raise invalidParams("if timestamp is earlier than Shanghai," & " payloadAttributes must be PayloadAttributesV1") proc forkchoiceUpdated*(ben: BeaconEngineRef, update: ForkchoiceStateV1, attrsOpt: Option[PayloadAttributes]): ForkchoiceUpdatedResponse = let com = ben.com db = com.db chain = ben.chain blockHash = ethHash update.headBlockHash validateVersion(attrsOpt, com) if blockHash == common.Hash256(): warn "Forkchoice requested update to zero hash" return simpleFCU(PayloadExecutionStatus.invalid) # Check whether we have the block yet in our database or not. If not, we'll # need to either trigger a sync, or to reject this forkchoice update for a # reason. var header: common.BlockHeader if not db.getBlockHeader(blockHash, header): # If the head hash is unknown (was not given to us in a newPayload request), # we cannot resolve the header, so not much to do. This could be extended in # the future to resolve from the `eth` network, but it's an unexpected case # that should be fixed, not papered over. if not ben.get(blockHash, header): warn "Forkchoice requested unknown head", hash = blockHash return simpleFCU(PayloadExecutionStatus.syncing) # Header advertised via a past newPayload request. Start syncing to it. # Before we do however, make sure any legacy sync in switched off so we # don't accidentally have 2 cycles running. if not ben.ttdReached(): ben.reachTTD() # TODO: cancel downloader info "Forkchoice requested sync to new head", number = header.blockNumber, hash = blockHash # Update sync header (if any) com.syncReqNewHead(header) return simpleFCU(PayloadExecutionStatus.syncing) # Block is known locally, just sanity check that the beacon client does not # attempt to push us back to before the merge. let blockNumber = header.blockNumber.truncate(uint64) if header.difficulty > 0.u256 or blockNumber == 0'u64: var td, ptd: DifficultyInt ttd = com.ttd.get(high(common.BlockNumber)) if not db.getTd(blockHash, td) or (blockNumber > 0'u64 and not db.getTd(header.parentHash, ptd)): error "TDs unavailable for TTD check", number = blockNumber, hash = blockHash, td = td, parent = header.parentHash, ptd = ptd return simpleFCU(PayloadExecutionStatus.invalid, "TDs unavailable for TDD check") if td < ttd or (blockNumber > 0'u64 and ptd > ttd): error "Refusing beacon update to pre-merge", number = blockNumber, hash = blockHash, diff = header.difficulty, ptd = ptd, ttd = ttd return invalidFCU() # If the head block is already in our canonical chain, the beacon client is # probably resyncing. Ignore the update. var canonHash: common.Hash256 if db.getBlockHash(header.blockNumber, canonHash) and canonHash == blockHash: # TODO should this be possible? # If we allow these types of reorgs, we will do lots and lots of reorgs during sync warn "Reorg to previous block" if chain.setCanonical(header) != ValidationResult.OK: return invalidFCU(com, header) elif chain.setCanonical(header) != ValidationResult.OK: return invalidFCU(com, header) # If the beacon client also advertised a finalized block, mark the local # chain final and completely in PoS mode. let finalizedBlockHash = ethHash update.finalizedBlockHash if finalizedBlockHash != common.Hash256(): if not ben.posFinalized: ben.finalizePoS() # TODO: If the finalized block is not in our canonical tree, somethings wrong var finalBlock: common.BlockHeader if not db.getBlockHeader(finalizedBlockHash, finalBlock): warn "Final block not available in database", hash=finalizedBlockHash raise invalidParams("finalized block header not available") var finalHash: common.Hash256 if not db.getBlockHash(finalBlock.blockNumber, finalHash): warn "Final block not in canonical chain", number=finalBlock.blockNumber, hash=finalizedBlockHash raise invalidParams("finalized block hash not available") if finalHash != finalizedBlockHash: warn "Final block not in canonical chain", number=finalBlock.blockNumber, expect=finalizedBlockHash, get=finalHash raise invalidParams("finalilized block not canonical") db.finalizedHeaderHash(finalizedBlockHash) let safeBlockHash = ethHash update.safeBlockHash if safeBlockHash != common.Hash256(): var safeBlock: common.BlockHeader if not db.getBlockHeader(safeBlockHash, safeBlock): warn "Safe block not available in database", hash = safeBlockHash raise invalidParams("safe head not available") var safeHash: common.Hash256 if not db.getBlockHash(safeBlock.blockNumber, safeHash): warn "Safe block hash not available in database", hash = safeHash raise invalidParams("safe block hash not available") if safeHash != safeBlockHash: warn "Safe block not in canonical chain", blockNumber=safeBlock.blockNumber, expect=safeBlockHash, get=safeHash raise invalidParams("safe head not canonical") db.safeHeaderHash(safeBlockHash) # If payload generation was requested, create a new block to be potentially # sealed by the beacon client. The payload will be requested later, and we # might replace it arbitrarilly many times in between. if attrsOpt.isSome: let attrs = attrsOpt.get() let payload = ben.generatePayload(attrs).valueOr: error "Failed to create sealing payload", err = error raise invalidAttr(error) let id = computePayloadId(blockHash, attrs) ben.put(id, ben.blockValue, payload) info "Created payload for sealing", id = id.toHex, hash = payload.blockHash, number = payload.blockNumber return validFCU(some(id), blockHash) return validFCU(none(PayloadID), blockHash)