# beacon_chain # Copyright (c) 2018-2023 Status Research & Development GmbH # Licensed and distributed under either of # * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT). # * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0). # at your option. This file may not be copied, modified, or distributed except according to those terms. when (NimMajor, NimMinor) < (1, 4): {.push raises: [Defect].} else: {.push raises: [].} import chronicles, chronos, ../spec/datatypes/base, ../consensus_object_pools/[blockchain_dag, block_quarantine, attestation_pool], ../eth1/eth1_monitor from ../spec/beaconstate import get_expected_withdrawals from ../spec/datatypes/capella import Withdrawal from ../spec/eth2_apis/dynamic_fee_recipients import DynamicFeeRecipientsStore, getDynamicFeeRecipient from ../validators/keystore_management import KeymanagerHost, getSuggestedFeeRecipient from ../validators/action_tracker import ActionTracker, getNextProposalSlot type ForkChoiceUpdatedInformation* = object payloadId*: PayloadID headBlockRoot*: Eth2Digest safeBlockRoot*: Eth2Digest finalizedBlockRoot*: Eth2Digest timestamp*: uint64 feeRecipient*: Eth1Address withdrawals*: Opt[seq[Withdrawal]] ConsensusManager* = object expectedSlot: Slot expectedBlockReceived: Future[bool] # Validated & Verified # ---------------------------------------------------------------- dag*: ChainDAGRef attestationPool*: ref AttestationPool # Missing info # ---------------------------------------------------------------- quarantine*: ref Quarantine # Execution layer integration # ---------------------------------------------------------------- eth1Monitor*: Eth1Monitor # Allow determination of whether there's an upcoming proposal # ---------------------------------------------------------------- actionTracker*: ActionTracker # Allow determination of preferred fee recipient during proposals # ---------------------------------------------------------------- dynamicFeeRecipientsStore: ref DynamicFeeRecipientsStore validatorsDir: string defaultFeeRecipient: Eth1Address # Tracking last proposal forkchoiceUpdated payload information # ---------------------------------------------------------------- forkchoiceUpdatedInfo*: Opt[ForkchoiceUpdatedInformation] optimisticHead: tuple[bid: BlockId, execution_block_hash: Eth2Digest] # Initialization # ------------------------------------------------------------------------------ func new*(T: type ConsensusManager, dag: ChainDAGRef, attestationPool: ref AttestationPool, quarantine: ref Quarantine, eth1Monitor: Eth1Monitor, actionTracker: ActionTracker, dynamicFeeRecipientsStore: ref DynamicFeeRecipientsStore, validatorsDir: string, defaultFeeRecipient: Eth1Address ): ref ConsensusManager = (ref ConsensusManager)( dag: dag, attestationPool: attestationPool, quarantine: quarantine, eth1Monitor: eth1Monitor, actionTracker: actionTracker, dynamicFeeRecipientsStore: dynamicFeeRecipientsStore, validatorsDir: validatorsDir, forkchoiceUpdatedInfo: Opt.none ForkchoiceUpdatedInformation, defaultFeeRecipient: defaultFeeRecipient ) # Consensus Management # ----------------------------------------------------------------------------------- proc checkExpectedBlock(self: var ConsensusManager) = if self.expectedBlockReceived == nil: return if self.dag.head.slot < self.expectedSlot: return self.expectedBlockReceived.complete(true) self.expectedBlockReceived = nil # Don't keep completed futures around! proc expectBlock*(self: var ConsensusManager, expectedSlot: Slot): Future[bool] = ## Return a future that will complete when a head is selected whose slot is ## equal or greater than the given slot, or a new expectation is created if self.expectedBlockReceived != nil: # Reset the old future to not leave it hanging.. an alternative would be to # cancel it, but it doesn't make any practical difference for now self.expectedBlockReceived.complete(false) let fut = newFuture[bool]("ConsensusManager.expectBlock") self.expectedSlot = expectedSlot self.expectedBlockReceived = fut # It might happen that by the time we're expecting a block, it might have # already been processed! self.checkExpectedBlock() return fut from eth/async_utils import awaitWithTimeout from web3/engine_api_types import ForkchoiceUpdatedResponse, PayloadExecutionStatus, PayloadStatusV1 func `$`(h: BlockHash): string = $h.asEth2Digest func shouldSyncOptimistically*( optimisticSlot, dagSlot, wallSlot: Slot): bool = ## Determine whether an optimistic execution block hash should be reported ## to the EL client instead of the current head as determined by fork choice. # Check whether optimistic head is sufficiently ahead of DAG const minProgress = 8 * SLOTS_PER_EPOCH # Set arbitrarily if optimisticSlot < dagSlot or optimisticSlot - dagSlot < minProgress: return false # Check whether optimistic head has synced sufficiently close to wall slot const maxAge = 2 * SLOTS_PER_EPOCH # Set arbitrarily if optimisticSlot < max(wallSlot, maxAge.Slot) - maxAge: return false true func shouldSyncOptimistically*(self: ConsensusManager, wallSlot: Slot): bool = if self.eth1Monitor == nil: return false if self.optimisticHead.execution_block_hash.isZero: return false shouldSyncOptimistically( optimisticSlot = self.optimisticHead.bid.slot, dagSlot = getStateField(self.dag.headState, slot), wallSlot = wallSlot) func optimisticHead*(self: ConsensusManager): BlockId = self.optimisticHead.bid func optimisticExecutionPayloadHash*(self: ConsensusManager): Eth2Digest = self.optimisticHead.execution_block_hash func setOptimisticHead*( self: var ConsensusManager, bid: BlockId, execution_block_hash: Eth2Digest) = self.optimisticHead = (bid: bid, execution_block_hash: execution_block_hash) proc runForkchoiceUpdated*( eth1Monitor: Eth1Monitor, headBlockRoot, safeBlockRoot, finalizedBlockRoot: Eth2Digest): Future[(PayloadExecutionStatus, Option[BlockHash])] {.async.} = # Allow finalizedBlockRoot to be 0 to avoid sync deadlocks. # # https://github.com/ethereum/EIPs/blob/master/EIPS/eip-3675.md#pos-events # has "Before the first finalized block occurs in the system the finalized # block hash provided by this event is stubbed with # `0x0000000000000000000000000000000000000000000000000000000000000000`." # and # https://github.com/ethereum/consensus-specs/blob/v1.3.0-rc.0/specs/bellatrix/validator.md#executionpayload # notes "`finalized_block_hash` is the hash of the latest finalized execution # payload (`Hash32()` if none yet finalized)" doAssert not headBlockRoot.isZero try: # Minimize window for Eth1 monitor to shut down connection await eth1Monitor.ensureDataProvider() let fcuR = awaitWithTimeout( forkchoiceUpdated( eth1Monitor, headBlockRoot, safeBlockRoot, finalizedBlockRoot), FORKCHOICEUPDATED_TIMEOUT): debug "runForkchoiceUpdated: forkchoiceUpdated timed out", headBlockRoot = shortLog(headBlockRoot), safeBlockRoot = shortLog(safeBlockRoot), finalizedBlockRoot = shortLog(finalizedBlockRoot) ForkchoiceUpdatedResponse( payloadStatus: PayloadStatusV1( status: PayloadExecutionStatus.syncing)) debug "runForkchoiceUpdated: ran forkchoiceUpdated", headBlockRoot, safeBlockRoot, finalizedBlockRoot, payloadStatus = $fcuR.payloadStatus.status, latestValidHash = $fcuR.payloadStatus.latestValidHash, validationError = $fcuR.payloadStatus.validationError return (fcuR.payloadStatus.status, fcuR.payloadStatus.latestValidHash) except CatchableError as err: warn "forkchoiceUpdated failed - check execution client", err = err.msg, headBlockRoot = shortLog(headBlockRoot), safeBlockRoot = shortLog(safeBlockRoot), finalizedBlockRoot = shortLog(finalizedBlockRoot) return (PayloadExecutionStatus.syncing, none BlockHash) proc runForkchoiceUpdatedDiscardResult*( eth1Monitor: Eth1Monitor, headBlockHash, safeBlockHash, finalizedBlockHash: Eth2Digest) {.async.} = discard await eth1Monitor.runForkchoiceUpdated( headBlockHash, safeBlockHash, finalizedBlockHash) from ../beacon_clock import GetBeaconTimeFn from ../fork_choice/fork_choice import mark_root_invalid proc updateExecutionClientHead( self: ref ConsensusManager, newHead: BeaconHead): Future[Opt[void]] {.async.} = if self.eth1Monitor.isNil: return Opt[void].ok() let headExecutionPayloadHash = self.dag.loadExecutionBlockRoot(newHead.blck) if headExecutionPayloadHash.isZero: # Blocks without execution payloads can't be optimistic. self.dag.markBlockVerified(self.quarantine[], newHead.blck.root) return Opt[void].ok() # Can't use dag.head here because it hasn't been updated yet let (payloadExecutionStatus, latestValidHash) = await self.eth1Monitor.runForkchoiceUpdated( headExecutionPayloadHash, newHead.safeExecutionPayloadHash, newHead.finalizedExecutionPayloadHash) case payloadExecutionStatus of PayloadExecutionStatus.valid: self.dag.markBlockVerified(self.quarantine[], newHead.blck.root) of PayloadExecutionStatus.invalid, PayloadExecutionStatus.invalid_block_hash: self.attestationPool[].forkChoice.mark_root_invalid(newHead.blck.root) self.quarantine[].addUnviable(newHead.blck.root) return Opt.none(void) of PayloadExecutionStatus.accepted, PayloadExecutionStatus.syncing: self.dag.optimisticRoots.incl newHead.blck.root return Opt[void].ok() proc updateHead*(self: var ConsensusManager, newHead: BlockRef) = ## Trigger fork choice and update the DAG with the new head block ## This does not automatically prune the DAG after finalization ## `pruneFinalized` must be called for pruning. # Store the new head in the chain DAG - this may cause epochs to be # justified and finalized self.dag.updateHead(newHead, self.quarantine[]) self.checkExpectedBlock() proc updateHead*(self: var ConsensusManager, wallSlot: Slot) = ## Trigger fork choice and update the DAG with the new head block ## This does not automatically prune the DAG after finalization ## `pruneFinalized` must be called for pruning. # Grab the new head according to our latest attestation data let newHead = self.attestationPool[].selectOptimisticHead( wallSlot.start_beacon_time).valueOr: warn "Head selection failed, using previous head", head = shortLog(self.dag.head), wallSlot return if self.dag.loadExecutionBlockRoot(newHead.blck).isZero: # Blocks without execution payloads can't be optimistic. self.dag.markBlockVerified(self.quarantine[], newHead.blck.root) self.updateHead(newHead.blck) func isSynced(dag: ChainDAGRef, wallSlot: Slot): bool = # This is a tweaked version of the validator_duties isSynced. TODO, refactor # that one so this becomes the default version, with the same information to # work with. For the head slot, use the DAG head regardless of what head the # proposer forkchoiceUpdated is using, because by the validator_duties might # be ready to actually propose, it's going to do so from the DAG head. Given # the defaultSyncHorizon, it will start triggering in time so that potential # discrepancies between the head here, and the head the DAG has (which might # not yet be updated) won't be visible. const defaultSyncHorizon = 50 if dag.head.slot + defaultSyncHorizon < wallSlot: false else: not dag.is_optimistic(dag.head.root) proc checkNextProposer( dag: ChainDAGRef, actionTracker: ActionTracker, dynamicFeeRecipientsStore: ref DynamicFeeRecipientsStore, wallSlot: Slot): Opt[(ValidatorIndex, ValidatorPubKey)] = let nextWallSlot = wallSlot + 1 # Avoid long rewinds during syncing, when it's not going to propose. Though # this is preparing for a proposal on `nextWallSlot`, it can't possibly yet # be on said slot, so still check just `wallSlot`. if not dag.isSynced(wallSlot): return Opt.none((ValidatorIndex, ValidatorPubKey)) let proposer = ? dag.getProposer(dag.head, nextWallSlot) if actionTracker.getNextProposalSlot(wallSlot) != nextWallSlot and dynamicFeeRecipientsStore[].getDynamicFeeRecipient( proposer, nextWallSlot.epoch).isNone: return Opt.none((ValidatorIndex, ValidatorPubKey)) let proposerKey = dag.validatorKey(proposer).get().toPubKey Opt.some((proposer, proposerKey)) proc checkNextProposer*(self: ref ConsensusManager, wallSlot: Slot): Opt[(ValidatorIndex, ValidatorPubKey)] = self.dag.checkNextProposer( self.actionTracker, self.dynamicFeeRecipientsStore, wallSlot) proc getFeeRecipient*( self: ConsensusManager, pubkey: ValidatorPubKey, validatorIdx: Opt[ValidatorIndex], epoch: Epoch): Eth1Address = let dynFeeRecipient = if validatorIdx.isSome: self.dynamicFeeRecipientsStore[].getDynamicFeeRecipient( validatorIdx.get(), epoch) else: Opt.none(Eth1Address) dynFeeRecipient.valueOr: self.validatorsDir.getSuggestedFeeRecipient( pubkey, self.defaultFeeRecipient).valueOr: # Ignore errors and use default - errors are logged in gsfr self.defaultFeeRecipient from ../spec/datatypes/bellatrix import PayloadID proc runProposalForkchoiceUpdated*( self: ref ConsensusManager, wallSlot: Slot) {.async.} = let nextWallSlot = wallSlot + 1 (validatorIndex, nextProposer) = self.checkNextProposer(wallSlot).valueOr: return debug "runProposalForkchoiceUpdated: expected to be proposing next slot", nextWallSlot, validatorIndex, nextProposer # Approximately lines up with validator_duties version. Used optimistcally/ # opportunistically, so mismatches are fine if not too frequent. let timestamp = withState(self.dag.headState): compute_timestamp_at_slot(forkyState.data, nextWallSlot) randomData = withState(self.dag.headState): get_randao_mix(forkyState.data, get_current_epoch(forkyState.data)).data feeRecipient = self[].getFeeRecipient( nextProposer, Opt.some(validatorIndex), nextWallSlot.epoch) withdrawals = withState(self.dag.headState): when stateFork >= BeaconStateFork.Capella: Opt.some get_expected_withdrawals(forkyState.data) else: Opt.none(seq[Withdrawal]) beaconHead = self.attestationPool[].getBeaconHead(self.dag.head) headBlockRoot = self.dag.loadExecutionBlockRoot(beaconHead.blck) if headBlockRoot.isZero: return try: let fcResult = awaitWithTimeout( forkchoiceUpdated( self.eth1Monitor, headBlockRoot, beaconHead.safeExecutionPayloadHash, beaconHead.finalizedExecutionPayloadHash, timestamp, randomData, feeRecipient, withdrawals), FORKCHOICEUPDATED_TIMEOUT): debug "runProposalForkchoiceUpdated: forkchoiceUpdated timed out" ForkchoiceUpdatedResponse( payloadStatus: PayloadStatusV1(status: PayloadExecutionStatus.syncing)) if fcResult.payloadStatus.status != PayloadExecutionStatus.valid or fcResult.payloadId.isNone: return self.forkchoiceUpdatedInfo = Opt.some ForkchoiceUpdatedInformation( payloadId: bellatrix.PayloadID(fcResult.payloadId.get), headBlockRoot: headBlockRoot, safeBlockRoot: beaconHead.safeExecutionPayloadHash, finalizedBlockRoot: beaconHead.finalizedExecutionPayloadHash, timestamp: timestamp, feeRecipient: feeRecipient, withdrawals: withdrawals) except CatchableError as err: error "Engine API fork-choice update failed", err = err.msg proc updateHeadWithExecution*( self: ref ConsensusManager, initialNewHead: BeaconHead, getBeaconTimeFn: GetBeaconTimeFn) {.async.} = ## Trigger fork choice and update the DAG with the new head block ## This does not automatically prune the DAG after finalization ## `pruneFinalized` must be called for pruning. # Grab the new head according to our latest attestation data try: # Ensure dag.updateHead has most current information var attempts = 0 newHead = initialNewHead while (await self.updateExecutionClientHead(newHead)).isErr: # This proc is called on every new block; guarantee timely return inc attempts const maxAttempts = 5 if attempts >= maxAttempts: warn "updateHeadWithExecution: too many attempts to recover from invalid payload", attempts, maxAttempts, newHead, initialNewHead break # Select new head for next attempt let wallTime = getBeaconTimeFn() nextHead = self.attestationPool[].selectOptimisticHead(wallTime).valueOr: warn "Head selection failed after invalid block, using previous head", newHead, wallSlot = wallTime.slotOrZero break warn "updateHeadWithExecution: attempting to recover from invalid payload", attempts, maxAttempts, newHead, initialNewHead, nextHead newHead = nextHead # Store the new head in the chain DAG - this may cause epochs to be # justified and finalized self.dag.updateHead(newHead.blck, self.quarantine[]) # If this node should propose next slot, start preparing payload. Both # fcUs are useful: the updateExecutionClientHead(newHead) call updates # the head state (including optimistic status) that self.dagUpdateHead # needs while runProposalForkchoiceUpdated requires RANDAO information # from the head state corresponding to the `newHead` block, which only # self.dag.updateHead(...) sets up. await self.runProposalForkchoiceUpdated(getBeaconTimeFn().slotOrZero) self[].checkExpectedBlock() except CatchableError as exc: debug "updateHeadWithExecution error", error = exc.msg proc pruneStateCachesAndForkChoice*(self: var ConsensusManager) = ## Prune unneeded and invalidated data after finalization ## - the DAG state checkpoints ## - the DAG EpochRef ## - the attestation pool/fork choice # Cleanup DAG & fork choice if we have a finalized head if self.dag.needStateCachesAndForkChoicePruning(): self.dag.pruneStateCachesDAG() self.attestationPool[].prune()