694 lines
28 KiB
Nim
694 lines
28 KiB
Nim
# beacon_chain
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# Copyright (c) 2018-2020 Status Research & Development GmbH
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# Licensed and distributed under either of
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# * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
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# * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
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# at your option. This file may not be copied, modified, or distributed except according to those terms.
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import
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# Standard library
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std/[os, osproc, random, sequtils, streams, tables],
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# Nimble packages
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stew/[objects], stew/shims/macros,
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chronos, metrics, json_rpc/[rpcserver, jsonmarshal],
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chronicles,
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json_serialization/std/[options, sets, net], serialization/errors,
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eth/db/kvstore,
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eth/[keys, async_utils], eth/p2p/discoveryv5/[protocol, enr],
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# Local modules
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spec/[datatypes, digest, crypto, helpers, network, signatures],
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spec/state_transition,
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conf, time, validator_pool,
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attestation_pool, exit_pool, block_pools/[spec_cache, chain_dag, clearance],
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eth2_network, keystore_management, beacon_node_common, beacon_node_types,
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nimbus_binary_common,
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eth1_monitor, version, ssz/merkleization,
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attestation_aggregation, sync_manager, sszdump,
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validator_slashing_protection
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# Metrics for tracking attestation and beacon block loss
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const delayBuckets = [-Inf, -4.0, -2.0, -1.0, -0.5, -0.1, -0.05,
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0.05, 0.1, 0.5, 1.0, 2.0, 4.0, 8.0, Inf]
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declareCounter beacon_attestations_sent,
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"Number of beacon chain attestations sent by this peer"
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declareHistogram beacon_attestation_sent_delay,
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"Time(s) between slot start and attestation sent moment",
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buckets = delayBuckets
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declareCounter beacon_blocks_proposed,
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"Number of beacon chain blocks sent by this peer"
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declareGauge(attached_validator_balance,
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"Validator balance at slot end of the first 64 validators, in Gwei",
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labels = ["pubkey"])
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declarePublicGauge(attached_validator_balance_total,
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"Validator balance of all attached validators, in Gwei")
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logScope: topics = "beacval"
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proc findValidator(state: BeaconState, pubKey: ValidatorPubKey):
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Option[ValidatorIndex] =
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let idx = state.validators.asSeq.findIt(it.pubKey == pubKey)
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if idx == -1:
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# We allow adding a validator even if its key is not in the state registry:
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# it might be that the deposit for this validator has not yet been processed
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notice "Validator deposit not yet processed, monitoring", pubKey
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none(ValidatorIndex)
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else:
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some(idx.ValidatorIndex)
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proc addLocalValidator*(node: BeaconNode,
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state: BeaconState,
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privKey: ValidatorPrivKey) =
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let pubKey = privKey.toPubKey()
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node.attachedValidators.addLocalValidator(
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pubKey, privKey, findValidator(state, pubKey))
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proc addLocalValidators*(node: BeaconNode) =
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for validatorKey in node.config.validatorKeys:
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node.addLocalValidator node.chainDag.headState.data.data, validatorKey
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proc addRemoteValidators*(node: BeaconNode) =
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# load all the validators from the child process - loop until `end`
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var line = newStringOfCap(120).TaintedString
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while line != "end" and running(node.vcProcess):
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if node.vcProcess.outputStream.readLine(line) and line != "end":
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let
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key = ValidatorPubKey.fromHex(line).get().initPubKey()
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index = findValidator(node.chainDag.headState.data.data, key)
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let v = AttachedValidator(pubKey: key,
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index: index,
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kind: ValidatorKind.remote,
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connection: ValidatorConnection(
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inStream: node.vcProcess.inputStream,
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outStream: node.vcProcess.outputStream,
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pubKeyStr: $key))
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node.attachedValidators.addRemoteValidator(key, v)
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proc getAttachedValidator*(node: BeaconNode,
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pubkey: ValidatorPubKey): AttachedValidator =
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node.attachedValidators.getValidator(pubkey)
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proc getAttachedValidator*(node: BeaconNode,
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state: BeaconState,
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idx: ValidatorIndex): AttachedValidator =
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if idx < state.validators.len.ValidatorIndex:
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let validator = node.getAttachedValidator(state.validators[idx].pubkey)
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if validator != nil and validator.index != some(idx.ValidatorIndex):
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# Update index, in case the validator was activated!
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notice "Validator activated", pubkey = validator.pubkey, index = idx
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validator.index = some(idx.ValidatorIndex)
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validator
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else:
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warn "Validator index out of bounds",
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idx, stateSlot = state.slot, validators = state.validators.len
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nil
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proc getAttachedValidator*(node: BeaconNode,
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epochRef: EpochRef,
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idx: ValidatorIndex): AttachedValidator =
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if idx < epochRef.validator_keys.len.ValidatorIndex:
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let validator = node.getAttachedValidator(epochRef.validator_keys[idx])
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if validator != nil and validator.index != some(idx.ValidatorIndex):
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# Update index, in case the validator was activated!
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notice "Validator activated", pubkey = validator.pubkey, index = idx
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validator.index = some(idx.ValidatorIndex)
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validator
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else:
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warn "Validator index out of bounds",
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idx, epoch = epochRef.epoch, validators = epochRef.validator_keys.len
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nil
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proc isSynced*(node: BeaconNode, head: BlockRef): bool =
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## TODO This function is here as a placeholder for some better heurestics to
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## determine if we're in sync and should be producing blocks and
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## attestations. Generally, the problem is that slot time keeps advancing
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## even when there are no blocks being produced, so there's no way to
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## distinguish validators geniunely going missing from the node not being
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## well connected (during a network split or an internet outage for
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## example). It would generally be correct to simply keep running as if
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## we were the only legit node left alive, but then we run into issues:
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## with enough many empty slots, the validator pool is emptied leading
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## to empty committees and lots of empty slot processing that will be
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## thrown away as soon as we're synced again.
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let
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# The slot we should be at, according to the clock
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beaconTime = node.beaconClock.now()
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wallSlot = beaconTime.toSlot()
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# TODO: MaxEmptySlotCount should likely involve the weak subjectivity period.
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# TODO if everyone follows this logic, the network will not recover from a
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# halt: nobody will be producing blocks because everone expects someone
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# else to do it
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if wallSlot.afterGenesis and head.slot + MaxEmptySlotCount < wallSlot.slot:
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false
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else:
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true
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proc sendAttestation*(
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node: BeaconNode, attestation: Attestation, num_active_validators: uint64) =
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node.network.broadcast(
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getAttestationTopic(node.forkDigest, attestation, num_active_validators),
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attestation)
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beacon_attestations_sent.inc()
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proc sendVoluntaryExit*(node: BeaconNode, exit: SignedVoluntaryExit) =
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node.network.broadcast(getVoluntaryExitsTopic(node.forkDigest), exit)
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proc sendAttesterSlashing*(node: BeaconNode, slashing: AttesterSlashing) =
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node.network.broadcast(getAttesterSlashingsTopic(node.forkDigest),
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slashing)
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proc sendProposerSlashing*(node: BeaconNode, slashing: ProposerSlashing) =
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node.network.broadcast(getProposerSlashingsTopic(node.forkDigest),
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slashing)
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proc sendAttestation*(node: BeaconNode, attestation: Attestation) =
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# For the validator API, which doesn't supply num_active_validators.
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let attestationBlck =
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node.chainDag.getRef(attestation.data.beacon_block_root)
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if attestationBlck.isNil:
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debug "Attempt to send attestation without corresponding block"
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return
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node.sendAttestation(
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attestation,
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count_active_validators(
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node.chainDag.getEpochRef(attestationBlck, attestation.data.target.epoch)))
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proc createAndSendAttestation(node: BeaconNode,
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fork: Fork,
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genesis_validators_root: Eth2Digest,
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validator: AttachedValidator,
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attestationData: AttestationData,
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committeeLen: int,
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indexInCommittee: int,
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num_active_validators: uint64) {.async.} =
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var attestation = await validator.produceAndSignAttestation(
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attestationData, committeeLen, indexInCommittee, fork,
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genesis_validators_root)
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node.sendAttestation(attestation, num_active_validators)
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if node.config.dumpEnabled:
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dump(node.config.dumpDirOutgoing, attestation.data, validator.pubKey)
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let wallTime = node.beaconClock.now()
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let deadline = attestationData.slot.toBeaconTime() +
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seconds(int(SECONDS_PER_SLOT div 3))
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let (delayStr, delayMillis) =
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if wallTime < deadline:
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("-" & $(deadline - wallTime), -toFloatSeconds(deadline - wallTime))
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else:
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($(wallTime - deadline), toFloatSeconds(wallTime - deadline))
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notice "Attestation sent", attestation = shortLog(attestation),
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validator = shortLog(validator), delay = delayStr,
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indexInCommittee = indexInCommittee
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beacon_attestation_sent_delay.observe(delayMillis)
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proc getBlockProposalEth1Data*(node: BeaconNode,
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state: BeaconState): BlockProposalEth1Data =
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if node.eth1Monitor.isNil:
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var pendingDepositsCount = state.eth1_data.deposit_count -
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state.eth1_deposit_index
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if pendingDepositsCount > 0:
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result.hasMissingDeposits = true
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else:
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result.vote = state.eth1_data
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else:
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let finalizedEpochRef = node.chainDag.getFinalizedEpochRef()
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result = node.eth1Monitor.getBlockProposalData(
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state, finalizedEpochRef.eth1_data, finalizedEpochRef.eth1_deposit_index)
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proc makeBeaconBlockForHeadAndSlot*(node: BeaconNode,
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randao_reveal: ValidatorSig,
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validator_index: ValidatorIndex,
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graffiti: GraffitiBytes,
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head: BlockRef,
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slot: Slot): Option[BeaconBlock] =
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# Advance state to the slot that we're proposing for
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node.chainDag.withState(node.chainDag.tmpState, head.atSlot(slot)):
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let
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eth1Proposal = node.getBlockProposalEth1Data(state)
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poolPtr = unsafeAddr node.chainDag # safe because restore is short-lived
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if eth1Proposal.hasMissingDeposits:
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error "Eth1 deposits not available. Skipping block proposal", slot
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return none(BeaconBlock)
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func restore(v: var HashedBeaconState) =
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# TODO address this ugly workaround - there should probably be a
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# `state_transition` that takes a `StateData` instead and updates
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# the block as well
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doAssert v.addr == addr poolPtr.tmpState.data
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assign(poolPtr.tmpState, poolPtr.headState)
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makeBeaconBlock(
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node.config.runtimePreset,
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hashedState,
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validator_index,
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head.root,
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randao_reveal,
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eth1Proposal.vote,
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graffiti,
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node.attestationPool[].getAttestationsForBlock(state, cache),
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eth1Proposal.deposits,
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node.exitPool[].getProposerSlashingsForBlock(),
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node.exitPool[].getAttesterSlashingsForBlock(),
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node.exitPool[].getVoluntaryExitsForBlock(),
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restore,
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cache)
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proc proposeSignedBlock*(node: BeaconNode,
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head: BlockRef,
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validator: AttachedValidator,
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newBlock: SignedBeaconBlock): BlockRef =
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let newBlockRef = node.chainDag.addRawBlock(node.quarantine, newBlock) do (
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blckRef: BlockRef, signedBlock: SignedBeaconBlock,
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epochRef: EpochRef, state: HashedBeaconState):
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# Callback add to fork choice if valid
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node.attestationPool[].addForkChoice(
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epochRef, blckRef, signedBlock.message,
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node.beaconClock.now().slotOrZero())
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if newBlockRef.isErr:
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warn "Unable to add proposed block to block pool",
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newBlock = shortLog(newBlock.message),
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blockRoot = shortLog(newBlock.root)
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return head
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notice "Block proposed",
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blck = shortLog(newBlock.message),
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blockRoot = shortLog(newBlockRef[].root),
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validator = shortLog(validator)
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if node.config.dumpEnabled:
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dump(node.config.dumpDirOutgoing, newBlock)
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node.network.broadcast(node.topicBeaconBlocks, newBlock)
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beacon_blocks_proposed.inc()
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return newBlockRef[]
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proc proposeBlock(node: BeaconNode,
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validator: AttachedValidator,
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validator_index: ValidatorIndex,
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head: BlockRef,
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slot: Slot): Future[BlockRef] {.async.} =
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if head.slot >= slot:
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# We should normally not have a head newer than the slot we're proposing for
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# but this can happen if block proposal is delayed
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warn "Skipping proposal, have newer head already",
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headSlot = shortLog(head.slot),
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headBlockRoot = shortLog(head.root),
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slot = shortLog(slot)
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return head
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let notSlashable = node.attachedValidators
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.slashingProtection
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.checkSlashableBlockProposal(validator.pubkey, slot)
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if notSlashable.isErr:
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warn "Slashing protection activated",
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validator = validator.pubkey,
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slot = slot,
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existingProposal = notSlashable.error
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return head
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let
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fork = node.chainDag.headState.data.data.fork
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genesis_validators_root =
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node.chainDag.headState.data.data.genesis_validators_root
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let
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randao = await validator.genRandaoReveal(
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fork, genesis_validators_root, slot)
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message = makeBeaconBlockForHeadAndSlot(
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node, randao, validator_index, node.graffitiBytes, head, slot)
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if not message.isSome():
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return head # already logged elsewhere!
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var
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newBlock = SignedBeaconBlock(
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message: message.get()
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)
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newBlock.root = hash_tree_root(newBlock.message)
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# TODO: recomputed in block proposal
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let signing_root = compute_block_root(
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fork, genesis_validators_root, slot, newBlock.root)
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node.attachedValidators
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.slashingProtection
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.registerBlock(validator.pubkey, slot, signing_root)
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newBlock.signature = await validator.signBlockProposal(
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fork, genesis_validators_root, slot, newBlock.root)
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return node.proposeSignedBlock(head, validator, newBlock)
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proc handleAttestations(node: BeaconNode, head: BlockRef, slot: Slot) =
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## Perform all attestations that the validators attached to this node should
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## perform during the given slot
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if slot + SLOTS_PER_EPOCH < head.slot:
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# The latest block we know about is a lot newer than the slot we're being
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# asked to attest to - this makes it unlikely that it will be included
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# at all.
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# TODO the oldest attestations allowed are those that are older than the
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# finalized epoch.. also, it seems that posting very old attestations
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# is risky from a slashing perspective. More work is needed here.
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warn "Skipping attestation, head is too recent",
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headSlot = shortLog(head.slot),
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slot = shortLog(slot)
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return
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let attestationHead = head.atSlot(slot)
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if head != attestationHead.blck:
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# In rare cases, such as when we're busy syncing or just slow, we'll be
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# attesting to a past state - we must then recreate the world as it looked
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# like back then
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notice "Attesting to a state in the past, falling behind?",
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headSlot = shortLog(head.slot),
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attestationHeadSlot = shortLog(attestationHead.slot),
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attestationSlot = shortLog(slot)
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trace "Checking attestations",
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attestationHeadRoot = shortLog(attestationHead.blck.root),
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attestationSlot = shortLog(slot)
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# Collect data to send before node.stateCache grows stale
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var attestations: seq[tuple[
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data: AttestationData, committeeLen, indexInCommittee: int,
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validator: AttachedValidator]]
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# We need to run attestations exactly for the slot that we're attesting to.
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# In case blocks went missing, this means advancing past the latest block
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# using empty slots as fillers.
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# https://github.com/ethereum/eth2.0-specs/blob/v1.0.0/specs/phase0/validator.md#validator-assignments
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let
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epochRef = node.chainDag.getEpochRef(
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attestationHead.blck, slot.compute_epoch_at_slot())
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committees_per_slot =
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get_committee_count_per_slot(epochRef)
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num_active_validators = count_active_validators(epochRef)
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fork = node.chainDag.headState.data.data.fork
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genesis_validators_root =
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node.chainDag.headState.data.data.genesis_validators_root
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for committee_index in 0'u64..<committees_per_slot:
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let committee = get_beacon_committee(
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epochRef, slot, committee_index.CommitteeIndex)
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for index_in_committee, validatorIdx in committee:
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let validator = node.getAttachedValidator(epochRef, validatorIdx)
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if validator != nil:
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let ad = makeAttestationData(
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epochRef, attestationHead, committee_index.CommitteeIndex)
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attestations.add((ad, committee.len, index_in_committee, validator))
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for a in attestations:
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let notSlashable = node.attachedValidators
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.slashingProtection
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.checkSlashableAttestation(
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a.validator.pubkey,
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a.data.source.epoch,
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a.data.target.epoch)
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if notSlashable.isOk():
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# TODO signing_root is recomputed in produceAndSignAttestation/signAttestation just after
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let signing_root = compute_attestation_root(
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fork, genesis_validators_root, a.data)
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node.attachedValidators
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.slashingProtection
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.registerAttestation(
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a.validator.pubkey,
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a.data.source.epoch,
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a.data.target.epoch,
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signing_root
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)
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traceAsyncErrors createAndSendAttestation(
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node, fork, genesis_validators_root, a.validator, a.data,
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a.committeeLen, a.indexInCommittee, num_active_validators)
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else:
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warn "Slashing protection activated for attestation",
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validator = a.validator.pubkey,
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badVoteDetails = $notSlashable.error
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proc handleProposal(node: BeaconNode, head: BlockRef, slot: Slot):
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Future[BlockRef] {.async.} =
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## Perform the proposal for the given slot, iff we have a validator attached
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## that is supposed to do so, given the shuffling at that slot for the given
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## head - to compute the proposer, we need to advance a state to the given
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## slot
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let proposer = node.chainDag.getProposer(head, slot)
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if proposer.isNone():
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return head
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let validator =
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node.attachedValidators.getValidator(proposer.get()[1])
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if validator != nil:
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return await proposeBlock(node, validator, proposer.get()[0], head, slot)
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debug "Expecting block proposal",
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|
headRoot = shortLog(head.root),
|
|
slot = shortLog(slot),
|
|
proposer_index = proposer.get()[0],
|
|
proposer = shortLog(proposer.get()[1].initPubKey())
|
|
|
|
return head
|
|
|
|
proc broadcastAggregatedAttestations(
|
|
node: BeaconNode, aggregationHead: BlockRef, aggregationSlot: Slot) {.async.} =
|
|
# The index is via a
|
|
# locally attested validator. Unlike in handleAttestations(...) there's a
|
|
# single one at most per slot (because that's how aggregation attestation
|
|
# works), so the machinery that has to handle looping across, basically a
|
|
# set of locally attached validators is in principle not necessary, but a
|
|
# way to organize this. Then the private key for that validator should be
|
|
# the corresponding one -- whatver they are, they match.
|
|
|
|
let
|
|
epochRef = node.chainDag.getEpochRef(aggregationHead, aggregationSlot.epoch)
|
|
fork = node.chainDag.headState.data.data.fork
|
|
genesis_validators_root =
|
|
node.chainDag.headState.data.data.genesis_validators_root
|
|
committees_per_slot = get_committee_count_per_slot(epochRef)
|
|
|
|
var
|
|
slotSigs: seq[Future[ValidatorSig]] = @[]
|
|
slotSigsData: seq[tuple[committee_index: uint64,
|
|
validator_idx: ValidatorIndex,
|
|
v: AttachedValidator]] = @[]
|
|
|
|
for committee_index in 0'u64..<committees_per_slot:
|
|
let committee = get_beacon_committee(
|
|
epochRef, aggregationSlot, committee_index.CommitteeIndex)
|
|
|
|
for index_in_committee, validatorIdx in committee:
|
|
let validator = node.getAttachedValidator(epochRef, validatorIdx)
|
|
if validator != nil:
|
|
# the validator index and private key pair.
|
|
slotSigs.add getSlotSig(validator, fork,
|
|
genesis_validators_root, aggregationSlot)
|
|
slotSigsData.add (committee_index, validatorIdx, validator)
|
|
|
|
await allFutures(slotSigs)
|
|
|
|
for curr in zip(slotSigsData, slotSigs):
|
|
let aggregateAndProof =
|
|
aggregate_attestations(node.attestationPool[], epochRef, aggregationSlot,
|
|
curr[0].committee_index.CommitteeIndex,
|
|
curr[0].validator_idx,
|
|
curr[1].read)
|
|
|
|
# Don't broadcast when, e.g., this node isn't aggregator
|
|
if aggregateAndProof.isSome:
|
|
let sig = await signAggregateAndProof(curr[0].v,
|
|
aggregateAndProof.get, fork, genesis_validators_root)
|
|
var signedAP = SignedAggregateAndProof(
|
|
message: aggregateAndProof.get,
|
|
signature: sig)
|
|
node.network.broadcast(node.topicAggregateAndProofs, signedAP)
|
|
notice "Aggregated attestation sent",
|
|
attestation = shortLog(signedAP.message.aggregate),
|
|
validator = shortLog(curr[0].v),
|
|
aggregationSlot
|
|
|
|
proc getSlotTimingEntropy(): int64 =
|
|
# Ensure SECONDS_PER_SLOT / ATTESTATION_PRODUCTION_DIVISOR >
|
|
# SECONDS_PER_SLOT / ATTESTATION_ENTROPY_DIVISOR, which will
|
|
# enure that the second condition can't go negative.
|
|
static: doAssert ATTESTATION_ENTROPY_DIVISOR > ATTESTATION_PRODUCTION_DIVISOR
|
|
|
|
# For each `slot`, a validator must generate a uniform random variable
|
|
# `slot_timing_entropy` between `(-SECONDS_PER_SLOT /
|
|
# ATTESTATION_ENTROPY_DIVISOR, SECONDS_PER_SLOT /
|
|
# ATTESTATION_ENTROPY_DIVISOR)` with millisecond resolution and using local
|
|
# entropy.
|
|
#
|
|
# Per issue discussion "validators served by the same beacon node can have
|
|
# the same attestation production time, i.e., they can share the source of
|
|
# the entropy and the actual slot_timing_entropy value."
|
|
const
|
|
slot_timing_entropy_upper_bound =
|
|
SECONDS_PER_SLOT.int64 * 1000 div ATTESTATION_ENTROPY_DIVISOR
|
|
slot_timing_entropy_lower_bound = 0-slot_timing_entropy_upper_bound
|
|
rand(range[(slot_timing_entropy_lower_bound + 1) ..
|
|
(slot_timing_entropy_upper_bound - 1)])
|
|
|
|
proc updateMetrics(node: BeaconNode) =
|
|
when defined(metrics):
|
|
# Technically, this only needs to be done on epoch transitions and if there's
|
|
# a reorg that spans an epoch transition, but it's easier to implement this
|
|
# way for now..
|
|
|
|
# We'll limit labelled metrics to the first 64, so that we don't overload
|
|
# prom
|
|
|
|
template state: untyped = node.chainDag.headState.data.data
|
|
|
|
var total: Gwei
|
|
var i = 0
|
|
for _, v in node.attachedValidators.validators:
|
|
let balance =
|
|
if v.index.isNone():
|
|
0.Gwei
|
|
elif v.index.get().uint64 >= state.balances.lenu64:
|
|
debug "Cannot get validator balance, index out of bounds",
|
|
pubkey = shortLog(v.pubkey), index = v.index.get(),
|
|
balances = state.balances.len,
|
|
stateRoot = node.chainDag.headState.data.root
|
|
0.Gwei
|
|
else:
|
|
state.balances[v.index.get()]
|
|
|
|
if i < 64:
|
|
attached_validator_balance.set(
|
|
min(balance, int64.high.uint64).int64,
|
|
labelValues = [shortLog(v.pubkey)])
|
|
else:
|
|
inc i
|
|
total += balance
|
|
|
|
node.attachedValidatorBalanceTotal = total
|
|
attached_validator_balance_total.set(min(total, int64.high.uint64).int64)
|
|
else:
|
|
discard
|
|
|
|
proc handleValidatorDuties*(node: BeaconNode, lastSlot, slot: Slot) {.async.} =
|
|
## Perform validator duties - create blocks, vote and aggregate existing votes
|
|
if node.attachedValidators.count == 0:
|
|
# Nothing to do because we have no validator attached
|
|
return
|
|
|
|
# The chainDag head might be updated by sync while we're working due to the
|
|
# await calls, thus we use a local variable to keep the logic straight here
|
|
var head = node.chainDag.head
|
|
if not node.isSynced(head):
|
|
notice "Syncing in progress; skipping validator duties for now",
|
|
slot, headSlot = head.slot
|
|
return
|
|
|
|
var curSlot = lastSlot + 1
|
|
|
|
# Start by checking if there's work we should have done in the past that we
|
|
# can still meaningfully do
|
|
while curSlot < slot:
|
|
notice "Catching up on validator duties",
|
|
curSlot = shortLog(curSlot),
|
|
lastSlot = shortLog(lastSlot),
|
|
slot = shortLog(slot)
|
|
|
|
# For every slot we're catching up, we'll propose then send
|
|
# attestations - head should normally be advancing along the same branch
|
|
# in this case
|
|
head = await handleProposal(node, head, curSlot)
|
|
|
|
# For each slot we missed, we need to send out attestations - if we were
|
|
# proposing during this time, we'll use the newly proposed head, else just
|
|
# keep reusing the same - the attestation that goes out will actually
|
|
# rewind the state to what it looked like at the time of that slot
|
|
handleAttestations(node, head, curSlot)
|
|
|
|
curSlot += 1
|
|
|
|
head = await handleProposal(node, head, slot)
|
|
|
|
# Fix timing attack: https://github.com/ethereum/eth2.0-specs/pull/2101
|
|
# A validator must create and broadcast the `attestation` to the associated
|
|
# attestation subnet when the earlier one of the following two events occurs:
|
|
#
|
|
# - The validator has received a valid block from the expected block
|
|
# proposer for the assigned `slot`. In this case, the validator must set a
|
|
# timer for `abs(slot_timing_entropy)`. The end of this timer will be the
|
|
# trigger for attestation production.
|
|
#
|
|
# - `SECONDS_PER_SLOT / ATTESTATION_PRODUCTION_DIVISOR +
|
|
# slot_timing_entropy` seconds have elapsed since the start of the `slot`
|
|
# (using the `slot_timing_entropy` generated for this slot)
|
|
|
|
# We've been doing lots of work up until now which took time. Normally, we
|
|
# send out attestations at the slot thirds-point, so we go back to the clock
|
|
# to see how much time we need to wait.
|
|
# TODO the beacon clock might jump here also. It's probably easier to complete
|
|
# the work for the whole slot using a monotonic clock instead, then deal
|
|
# with any clock discrepancies once only, at the start of slot timer
|
|
# processing..
|
|
let slotTimingEntropy = getSlotTimingEntropy()
|
|
|
|
template sleepToSlotOffsetWithHeadUpdate(extra: chronos.Duration, msg: static string) =
|
|
let waitTime = node.beaconClock.fromNow(slot.toBeaconTime(extra))
|
|
if waitTime.inFuture:
|
|
discard await withTimeout(
|
|
node.processor[].blockReceivedDuringSlot, waitTime.offset)
|
|
|
|
# Might have gotten a valid beacon block this slot, which triggers the
|
|
# first case, in which we wait for another abs(slotTimingEntropy).
|
|
if node.processor[].blockReceivedDuringSlot.finished:
|
|
await sleepAsync(
|
|
milliseconds(max(slotTimingEntropy, 0 - slotTimingEntropy)))
|
|
|
|
# Time passed - we might need to select a new head in that case
|
|
node.processor[].updateHead(slot)
|
|
head = node.chainDag.head
|
|
|
|
sleepToSlotOffsetWithHeadUpdate(
|
|
milliseconds(SECONDS_PER_SLOT.int64 * 1000 div ATTESTATION_PRODUCTION_DIVISOR +
|
|
slotTimingEntropy),
|
|
"Waiting to send attestations")
|
|
|
|
handleAttestations(node, head, slot)
|
|
|
|
updateMetrics(node) # the important stuff is done, update the vanity numbers
|
|
|
|
# https://github.com/ethereum/eth2.0-specs/blob/v1.0.0/specs/phase0/validator.md#broadcast-aggregate
|
|
# If the validator is selected to aggregate (is_aggregator), then they
|
|
# broadcast their best aggregate as a SignedAggregateAndProof to the global
|
|
# aggregate channel (beacon_aggregate_and_proof) two-thirds of the way
|
|
# through the slot-that is, SECONDS_PER_SLOT * 2 / 3 seconds after the start
|
|
# of slot.
|
|
if slot > 2:
|
|
discard await node.beaconClock.sleepToSlotOffset(
|
|
seconds(int64(SECONDS_PER_SLOT * 2) div 3), slot,
|
|
"Waiting to aggregate attestations")
|
|
|
|
await broadcastAggregatedAttestations(node, head, slot)
|
|
|
|
if node.eth1Monitor != nil and (slot mod SLOTS_PER_EPOCH) == 0:
|
|
let finalizedEpochRef = node.chainDag.getFinalizedEpochRef()
|
|
discard node.eth1Monitor.trackFinalizedState(
|
|
finalizedEpochRef.eth1_data, finalizedEpochRef.eth1_deposit_index)
|
|
|