# beacon_chain # Copyright (c) 2018-2020 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. import # Standard library std/[algorithm, os, tables, strutils, sequtils, times, math, terminal], std/[osproc, random], # Nimble packages stew/[objects, byteutils, endians2], stew/shims/macros, chronos, confutils, metrics, json_rpc/[rpcserver, jsonmarshal], chronicles, bearssl, blscurve, json_serialization/std/[options, sets, net], serialization/errors, eth/[keys, async_utils], eth/common/eth_types_json_serialization, eth/db/[kvstore, kvstore_sqlite3], eth/p2p/enode, eth/p2p/discoveryv5/[protocol, enr], # Local modules spec/[datatypes, digest, crypto, beaconstate, helpers, network, presets], spec/state_transition, conf, time, beacon_chain_db, validator_pool, extras, attestation_pool, exit_pool, eth2_network, eth2_discovery, beacon_node_common, beacon_node_types, block_pools/[spec_cache, chain_dag, quarantine, clearance, block_pools_types], nimbus_binary_common, network_metadata, mainchain_monitor, version, ssz/[merkleization], merkle_minimal, sync_protocol, request_manager, keystore_management, interop, statusbar, sync_manager, validator_duties, validator_api, validator_slashing_protection, ./eth2_processor const genesisFile* = "genesis.ssz" hasPrompt = not defined(withoutPrompt) type RpcServer* = RpcHttpServer # "state" is already taken by BeaconState BeaconNodeStatus* = enum Starting, Running, Stopping # this needs to be global, so it can be set in the Ctrl+C signal handler var status = BeaconNodeStatus.Starting template init(T: type RpcHttpServer, ip: ValidIpAddress, port: Port): T = newRpcHttpServer([initTAddress(ip, port)]) # https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#interop-metrics declareGauge beacon_slot, "Latest slot of the beacon chain state" declareGauge beacon_head_slot, "Slot of the head block of the beacon chain" # Finalization tracking declareGauge finalization_delay, "Epoch delay between scheduled epoch and finalized epoch" declareGauge ticks_delay, "How long does to take to run the onSecond loop" logScope: topics = "beacnde" proc getStateFromSnapshot(conf: BeaconNodeConf, stateSnapshotContents: ref string): NilableBeaconStateRef = var genesisPath = conf.dataDir/genesisFile snapshotContents: TaintedString writeGenesisFile = false if conf.stateSnapshot.isSome: let snapshotPath = conf.stateSnapshot.get.string snapshotExt = splitFile(snapshotPath).ext if cmpIgnoreCase(snapshotExt, ".ssz") != 0: error "The supplied state snapshot must be a SSZ file", suppliedPath = snapshotPath quit 1 snapshotContents = readFile(snapshotPath) if fileExists(genesisPath): let genesisContents = readFile(genesisPath) if snapshotContents != genesisContents: error "Data directory not empty. Existing genesis state differs from supplied snapshot", dataDir = conf.dataDir.string, snapshot = snapshotPath quit 1 else: debug "No previous genesis state. Importing snapshot", genesisPath, dataDir = conf.dataDir.string writeGenesisFile = true genesisPath = snapshotPath elif fileExists(genesisPath): try: snapshotContents = readFile(genesisPath) except CatchableError as err: error "Failed to read genesis file", err = err.msg quit 1 elif stateSnapshotContents != nil: swap(snapshotContents, TaintedString stateSnapshotContents[]) else: # No snapshot was provided. We should wait for genesis. return nil result = try: newClone(SSZ.decode(snapshotContents, BeaconState)) except SerializationError: error "Failed to import genesis file", path = genesisPath quit 1 info "Loaded genesis state", path = genesisPath if writeGenesisFile: try: notice "Writing genesis to data directory", path = conf.dataDir/genesisFile writeFile(conf.dataDir/genesisFile, snapshotContents.string) except CatchableError as err: error "Failed to persist genesis file to data dir", err = err.msg, genesisFile = conf.dataDir/genesisFile quit 1 func enrForkIdFromState(state: BeaconState): ENRForkID = let forkVer = state.fork.current_version forkDigest = compute_fork_digest(forkVer, state.genesis_validators_root) ENRForkID( fork_digest: forkDigest, next_fork_version: forkVer, next_fork_epoch: FAR_FUTURE_EPOCH) proc init*(T: type BeaconNode, rng: ref BrHmacDrbgContext, conf: BeaconNodeConf, stateSnapshotContents: ref string): Future[BeaconNode] {.async.} = let netKeys = getPersistentNetKeys(rng[], conf) nickname = if conf.nodeName == "auto": shortForm(netKeys) else: conf.nodeName db = BeaconChainDB.init(kvStore SqStoreRef.init(conf.databaseDir, "nbc").tryGet()) var mainchainMonitor: MainchainMonitor if not ChainDAGRef.isInitialized(db): # Fresh start - need to load a genesis state from somewhere var genesisState = conf.getStateFromSnapshot(stateSnapshotContents) # Try file from command line first if genesisState.isNil: if conf.web3Url.len == 0: fatal "Web3 URL not specified" quit 1 if conf.depositContractAddress.isNone: fatal "Deposit contract address not specified" quit 1 if conf.depositContractDeployedAt.isNone: # When we don't have a known genesis state, the network metadata # must specify the deployment block of the contract. fatal "Deposit contract deployment block not specified" quit 1 let web3 = web3Provider(conf.web3Url) let deployedAtAsHash = if conf.depositContractDeployedAt.get.startsWith "0x": try: BlockHash.fromHex conf.depositContractDeployedAt.get except ValueError: fatal "Invalid hex value specified for deposit-contract-block" quit 1 else: let blockNum = try: parseBiggestUInt conf.depositContractDeployedAt.get except ValueError: fatal "Invalid nummeric value for deposit-contract-block" quit 1 await getEth1BlockHash(conf.web3Url, blockId blockNum) # TODO Could move this to a separate "GenesisMonitor" process or task # that would do only this - see Paul's proposal for this. mainchainMonitor = MainchainMonitor.init( conf.runtimePreset, web3, conf.depositContractAddress.get, Eth1Data(block_hash: deployedAtAsHash.asEth2Digest, deposit_count: 0)) mainchainMonitor.start() genesisState = await mainchainMonitor.waitGenesis() info "Eth2 genesis state detected", genesisTime = genesisState.genesisTime, eth1Block = genesisState.eth1_data.block_hash, totalDeposits = genesisState.eth1_data.deposit_count # This is needed to prove the not nil property from here on if genesisState == nil: doAssert false else: if genesisState.slot != GENESIS_SLOT: # TODO how to get a block from a non-genesis state? error "Starting from non-genesis state not supported", stateSlot = genesisState.slot, stateRoot = hash_tree_root(genesisState[]) quit 1 let tailBlock = get_initial_beacon_block(genesisState[]) try: ChainDAGRef.preInit(db, genesisState[], tailBlock) doAssert ChainDAGRef.isInitialized(db), "preInit should have initialized db" except CatchableError as e: error "Failed to initialize database", err = e.msg quit 1 if stateSnapshotContents != nil: # The memory for the initial snapshot won't be needed anymore stateSnapshotContents[] = "" # TODO check that genesis given on command line (if any) matches database let chainDagFlags = if conf.verifyFinalization: {verifyFinalization} else: {} chainDag = init(ChainDAGRef, conf.runtimePreset, db, chainDagFlags) quarantine = QuarantineRef() if mainchainMonitor.isNil and conf.web3Url.len > 0 and conf.depositContractAddress.isSome: mainchainMonitor = MainchainMonitor.init( conf.runtimePreset, web3Provider(conf.web3Url), conf.depositContractAddress.get, chainDag.headState.data.data.eth1_data) # TODO if we don't have any validators attached, we don't need a mainchain # monitor mainchainMonitor.start() let rpcServer = if conf.rpcEnabled: RpcServer.init(conf.rpcAddress, conf.rpcPort) else: nil let enrForkId = enrForkIdFromState(chainDag.headState.data.data) topicBeaconBlocks = getBeaconBlocksTopic(enrForkId.forkDigest) topicAggregateAndProofs = getAggregateAndProofsTopic(enrForkId.forkDigest) network = createEth2Node(rng, conf, enrForkId) attestationPool = newClone(AttestationPool.init(chainDag, quarantine)) exitPool = newClone(ExitPool.init(chainDag, quarantine)) var res = BeaconNode( nickname: nickname, graffitiBytes: if conf.graffiti.isSome: conf.graffiti.get.GraffitiBytes else: defaultGraffitiBytes(), network: network, netKeys: netKeys, db: db, config: conf, chainDag: chainDag, quarantine: quarantine, attestationPool: attestationPool, exitPool: exitPool, mainchainMonitor: mainchainMonitor, beaconClock: BeaconClock.init(chainDag.headState.data.data), rpcServer: rpcServer, forkDigest: enrForkId.forkDigest, topicBeaconBlocks: topicBeaconBlocks, topicAggregateAndProofs: topicAggregateAndProofs, ) res.attachedValidators = ValidatorPool.init( SlashingProtectionDB.init( chainDag.headState.data.data.genesis_validators_root, when UseSlashingProtection: kvStore SqStoreRef.init(conf.validatorsDir(), "slashing_protection").tryGet() else: KvStoreRef() ) ) proc getWallTime(): BeaconTime = res.beaconClock.now() res.processor = Eth2Processor.new( conf, chainDag, attestationPool, exitPool, quarantine, getWallTime) res.requestManager = RequestManager.init( network, res.processor.blocksQueue) if res.config.inProcessValidators: res.addLocalValidators() else: res.vcProcess = startProcess(getAppDir() & "/signing_process".addFileExt(ExeExt), getCurrentDir(), [$res.config.validatorsDir, $res.config.secretsDir]) res.addRemoteValidators() # This merely configures the BeaconSync # The traffic will be started when we join the network. network.initBeaconSync(chainDag, enrForkId.forkDigest) return res func verifyFinalization(node: BeaconNode, slot: Slot) = # Epoch must be >= 4 to check finalization const SETTLING_TIME_OFFSET = 1'u64 let epoch = slot.compute_epoch_at_slot() # Don't static-assert this -- if this isn't called, don't require it doAssert SLOTS_PER_EPOCH > SETTLING_TIME_OFFSET # Intentionally, loudly assert. Point is to fail visibly and unignorably # during testing. if epoch >= 4 and slot mod SLOTS_PER_EPOCH > SETTLING_TIME_OFFSET: let finalizedEpoch = node.chainDag.finalizedHead.slot.compute_epoch_at_slot() # Finalization rule 234, that has the most lag slots among the cases, sets # state.finalized_checkpoint = old_previous_justified_checkpoint.epoch + 3 # and then state.slot gets incremented, to increase the maximum offset, if # finalization occurs every slot, to 4 slots vs scheduledSlot. doAssert finalizedEpoch + 4 >= epoch proc installAttestationSubnetHandlers(node: BeaconNode, subnets: set[uint8]) = var attestationSubscriptions: seq[Future[void]] = @[] # https://github.com/ethereum/eth2.0-specs/blob/v0.12.3/specs/phase0/p2p-interface.md#attestations-and-aggregation for subnet in subnets: attestationSubscriptions.add(node.network.subscribe( getAttestationTopic(node.forkDigest, subnet))) waitFor allFutures(attestationSubscriptions) # https://github.com/ethereum/eth2.0-specs/blob/v0.12.3/specs/phase0/p2p-interface.md#metadata node.network.metadata.seq_number += 1 for subnet in subnets: node.network.metadata.attnets[subnet] = true proc cycleAttestationSubnets(node: BeaconNode, slot: Slot) = static: doAssert RANDOM_SUBNETS_PER_VALIDATOR == 1 let epochParity = slot.epoch mod 2 var attachedValidators: seq[ValidatorIndex] for validatorIndex in 0 ..< node.chainDag.headState.data.data.validators.len: if node.getAttachedValidator( node.chainDag.headState.data.data, validatorIndex.ValidatorIndex) != nil: attachedValidators.add validatorIndex.ValidatorIndex if attachedValidators.len == 0: return let (newAttestationSubnets, expiringSubnets, newSubnets) = get_attestation_subnet_changes( node.chainDag.headState.data.data, attachedValidators, node.attestationSubnets, slot.epoch) node.attestationSubnets = newAttestationSubnets debug "Attestation subnets", expiring_subnets = expiringSubnets, current_epoch_subnets = node.attestationSubnets.subscribedSubnets[1 - epochParity], upcoming_subnets = node.attestationSubnets.subscribedSubnets[epochParity], new_subnets = newSubnets, stability_subnet = node.attestationSubnets.stabilitySubnet, stability_subnet_expiration_epoch = node.attestationSubnets.stabilitySubnetExpirationEpoch block: var unsubscriptions: seq[Future[void]] = @[] for expiringSubnet in expiringSubnets: unsubscriptions.add(node.network.unsubscribe( getAttestationTopic(node.forkDigest, expiringSubnet))) waitFor allFutures(unsubscriptions) # https://github.com/ethereum/eth2.0-specs/blob/v0.12.3/specs/phase0/p2p-interface.md#metadata # The race condition window is smaller by placing the fast, local, and # synchronous operation after a variable-latency, asynchronous action. node.network.metadata.seq_number += 1 for expiringSubnet in expiringSubnets: node.network.metadata.attnets[expiringSubnet] = false node.installAttestationSubnetHandlers(newSubnets) block: let subscribed_subnets = node.attestationSubnets.subscribedSubnets[0] + node.attestationSubnets.subscribedSubnets[1] + {node.attestationSubnets.stabilitySubnet.uint8} for subnet in 0'u8 ..< ATTESTATION_SUBNET_COUNT: doAssert node.network.metadata.attnets[subnet] == (subnet in subscribed_subnets) proc getAttestationHandlers(node: BeaconNode): Future[void] = var initialSubnets: set[uint8] for i in 0'u8 ..< ATTESTATION_SUBNET_COUNT: initialSubnets.incl i node.installAttestationSubnetHandlers(initialSubnets) # https://github.com/ethereum/eth2.0-specs/blob/v0.12.3/specs/phase0/validator.md#phase-0-attestation-subnet-stability let wallEpoch = node.beaconClock.now().slotOrZero().epoch node.attestationSubnets.stabilitySubnet = rand(ATTESTATION_SUBNET_COUNT - 1).uint64 node.attestationSubnets.stabilitySubnetExpirationEpoch = wallEpoch + getStabilitySubnetLength() # Sets the "current" and "future" attestation subnets. One of these gets # replaced by get_attestation_subnet_changes() immediately. node.attestationSubnets.subscribedSubnets[0] = initialSubnets node.attestationSubnets.subscribedSubnets[1] = initialSubnets node.network.subscribe(getAggregateAndProofsTopic(node.forkDigest)) proc addMessageHandlers(node: BeaconNode): Future[void] = allFutures( # As a side-effect, this gets the attestation subnets too. node.network.subscribe(node.topicBeaconBlocks), node.network.subscribe(getAttesterSlashingsTopic(node.forkDigest)), node.network.subscribe(getProposerSlashingsTopic(node.forkDigest)), node.network.subscribe(getVoluntaryExitsTopic(node.forkDigest)), node.getAttestationHandlers() ) func getTopicSubscriptionEnabled(node: BeaconNode): bool = node.attestationSubnets.subscribedSubnets[0].len + node.attestationSubnets.subscribedSubnets[1].len > 0 proc removeMessageHandlers(node: BeaconNode): Future[void] = node.attestationSubnets.subscribedSubnets[0] = {} node.attestationSubnets.subscribedSubnets[1] = {} doAssert not node.getTopicSubscriptionEnabled() var unsubscriptions = mapIt( [getBeaconBlocksTopic(node.forkDigest), getVoluntaryExitsTopic(node.forkDigest), getProposerSlashingsTopic(node.forkDigest), getAttesterSlashingsTopic(node.forkDigest), getAggregateAndProofsTopic(node.forkDigest)], node.network.unsubscribe(it)) for subnet in 0'u64 ..< ATTESTATION_SUBNET_COUNT: unsubscriptions.add node.network.unsubscribe( getAttestationTopic(node.forkDigest, subnet)) allFutures(unsubscriptions) proc onSlotStart(node: BeaconNode, lastSlot, scheduledSlot: Slot) {.async.} = ## Called at the beginning of a slot - usually every slot, but sometimes might ## skip a few in case we're running late. ## lastSlot: the last slot that we successfully processed, so we know where to ## start work from ## scheduledSlot: the slot that we were aiming for, in terms of timing let # The slot we should be at, according to the clock beaconTime = node.beaconClock.now() wallSlot = beaconTime.toSlot() finalizedEpoch = node.chainDag.finalizedHead.blck.slot.compute_epoch_at_slot() info "Slot start", lastSlot = shortLog(lastSlot), scheduledSlot = shortLog(scheduledSlot), beaconTime = shortLog(beaconTime), peers = len(node.network.peerPool), head = shortLog(node.chainDag.head), headEpoch = shortLog(node.chainDag.head.slot.compute_epoch_at_slot()), finalized = shortLog(node.chainDag.finalizedHead.blck), finalizedEpoch = shortLog(finalizedEpoch) # Check before any re-scheduling of onSlotStart() checkIfShouldStopAtEpoch(scheduledSlot, node.config.stopAtEpoch) if not wallSlot.afterGenesis or (wallSlot.slot < lastSlot): let slot = if wallSlot.afterGenesis: wallSlot.slot else: GENESIS_SLOT nextSlot = slot + 1 # At least GENESIS_SLOT + 1! # This can happen if the system clock changes time for example, and it's # pretty bad # TODO shut down? time either was or is bad, and PoS relies on accuracy.. warn "Beacon clock time moved back, rescheduling slot actions", beaconTime = shortLog(beaconTime), lastSlot = shortLog(lastSlot), scheduledSlot = shortLog(scheduledSlot), nextSlot = shortLog(nextSlot) addTimer(saturate(node.beaconClock.fromNow(nextSlot))) do (p: pointer): asyncCheck node.onSlotStart(slot, nextSlot) return let slot = wallSlot.slot # afterGenesis == true! nextSlot = slot + 1 beacon_slot.set slot.int64 finalization_delay.set scheduledSlot.epoch.int64 - finalizedEpoch.int64 if node.config.verifyFinalization: verifyFinalization(node, scheduledSlot) if slot > lastSlot + SLOTS_PER_EPOCH: # We've fallen behind more than an epoch - there's nothing clever we can # do here really, except skip all the work and try again later. # TODO how long should the period be? Using an epoch because that's roughly # how long attestations remain interesting # TODO should we shut down instead? clearly we're unable to keep up warn "Unable to keep up, skipping ahead", lastSlot = shortLog(lastSlot), slot = shortLog(slot), nextSlot = shortLog(nextSlot), scheduledSlot = shortLog(scheduledSlot) addTimer(saturate(node.beaconClock.fromNow(nextSlot))) do (p: pointer): # We pass the current slot here to indicate that work should be skipped! asyncCheck node.onSlotStart(slot, nextSlot) return # Whatever we do during the slot, we need to know the head, because this will # give us a state to work with and thus a shuffling. # TODO typically, what consitutes correct actions stays constant between slot # updates and is stable across some epoch transitions as well - see how # we can avoid recalculating everything here # TODO if the head is very old, that is indicative of something being very # wrong - us being out of sync or disconnected from the network - need # to consider what to do in that case: # * nothing - the other parts of the application will reconnect and # start listening to broadcasts, learn a new head etc.. # risky, because the network might stall if everyone does # this, because no blocks will be produced # * shut down - this allows the user to notice and take action, but is # kind of harsh # * keep going - we create blocks and attestations as usual and send them # out - if network conditions improve, fork choice should # eventually select the correct head and the rest will # disappear naturally - risky because user is not aware, # and might lose stake on canonical chain but "just works" # when reconnected.. discard node.updateHead(slot) # TODO is the slot of the clock or the head block more interesting? provide # rationale in comment beacon_head_slot.set slot.int64 # Time passes in here.. await node.handleValidatorDuties(lastSlot, slot) let nextSlotStart = saturate(node.beaconClock.fromNow(nextSlot)) info "Slot end", slot = shortLog(slot), nextSlot = shortLog(nextSlot), head = shortLog(node.chainDag.head), headEpoch = shortLog(node.chainDag.head.slot.compute_epoch_at_slot()), finalizedHead = shortLog(node.chainDag.finalizedHead.blck), finalizedEpoch = shortLog(node.chainDag.finalizedHead.blck.slot.compute_epoch_at_slot()) # Syncing tends to be ~1 block/s, and allow for an epoch of time for libp2p # subscribing to spin up. The faster the sync, the more wallSlot - headSlot # lead time is required const TOPIC_SUBSCRIBE_THRESHOLD_SLOTS = 64 HYSTERESIS_BUFFER = 16 let syncQueueLen = node.syncManager.syncQueueLen topicSubscriptionEnabled = node.getTopicSubscriptionEnabled() if # Don't enable if already enabled; to avoid race conditions requires care, # but isn't crucial, as this condition spuriously fail, but the next time, # should properly succeed. not topicSubscriptionEnabled and # SyncManager forward sync by default runs until maxHeadAge slots, or one # epoch range is achieved. This particular condition has a couple caveats # including that under certain conditions, debtsCount appears to push len # (here, syncQueueLen) to underflow-like values; and even when exactly at # the expected walltime slot the queue isn't necessarily empty. Therefore # TOPIC_SUBSCRIBE_THRESHOLD_SLOTS is not exactly the number of slots that # are left. Furthermore, even when 0 peers are being used, this won't get # to 0 slots in syncQueueLen, but that's a vacuous condition given that a # networking interaction cannot happen under such circumstances. syncQueueLen < TOPIC_SUBSCRIBE_THRESHOLD_SLOTS: # When node.cycleAttestationSubnets() is enabled more properly, integrate # this into the node.cycleAttestationSubnets() call. debug "Enabling topic subscriptions", wallSlot = slot, headSlot = node.chainDag.head.slot, syncQueueLen await node.addMessageHandlers() doAssert node.getTopicSubscriptionEnabled() elif topicSubscriptionEnabled and syncQueueLen > TOPIC_SUBSCRIBE_THRESHOLD_SLOTS + HYSTERESIS_BUFFER and # Filter out underflow from debtsCount; plausible queue lengths can't # exceed wallslot, with safety margin. syncQueueLen < 2 * slot.uint64: debug "Disabling topic subscriptions", wallSlot = slot, headSlot = node.chainDag.head.slot, syncQueueLen await node.removeMessageHandlers() # Subscription or unsubscription might have occurred; recheck if slot.isEpoch and node.getTopicSubscriptionEnabled: node.cycleAttestationSubnets(slot) when declared(GC_fullCollect): # The slots in the beacon node work as frames in a game: we want to make # sure that we're ready for the next one and don't get stuck in lengthy # garbage collection tasks when time is of essence in the middle of a slot - # while this does not guarantee that we'll never collect during a slot, it # makes sure that all the scratch space we used during slot tasks (logging, # temporary buffers etc) gets recycled for the next slot that is likely to # need similar amounts of memory. GC_fullCollect() addTimer(nextSlotStart) do (p: pointer): asyncCheck node.onSlotStart(slot, nextSlot) proc handleMissingBlocks(node: BeaconNode) = let missingBlocks = node.quarantine.checkMissing() if missingBlocks.len > 0: info "Requesting detected missing blocks", blocks = shortLog(missingBlocks) node.requestManager.fetchAncestorBlocks(missingBlocks) proc onSecond(node: BeaconNode) = ## This procedure will be called once per second. if not(node.syncManager.inProgress): node.handleMissingBlocks() proc runOnSecondLoop(node: BeaconNode) {.async.} = let sleepTime = chronos.seconds(1) const nanosecondsIn1s = float(chronos.seconds(1).nanoseconds) while true: let start = chronos.now(chronos.Moment) await chronos.sleepAsync(sleepTime) let afterSleep = chronos.now(chronos.Moment) let sleepTime = afterSleep - start node.onSecond() let finished = chronos.now(chronos.Moment) let processingTime = finished - afterSleep ticks_delay.set(sleepTime.nanoseconds.float / nanosecondsIn1s) debug "onSecond task completed", sleepTime, processingTime proc startSyncManager(node: BeaconNode) = func getLocalHeadSlot(): Slot = node.chainDag.head.slot proc getLocalWallSlot(): Slot = let epoch = node.beaconClock.now().slotOrZero.compute_epoch_at_slot() + 1'u64 epoch.compute_start_slot_at_epoch() func getFirstSlotAtFinalizedEpoch(): Slot = let fepoch = node.chainDag.headState.data.data.finalized_checkpoint.epoch compute_start_slot_at_epoch(fepoch) proc scoreCheck(peer: Peer): bool = if peer.score < PeerScoreLowLimit: try: debug "Peer score is too low, disconnecting", peer = peer, peer_score = peer.score, score_low_limit = PeerScoreLowLimit, score_high_limit = PeerScoreHighLimit # We do not care about result of this operation, because even if # disconnect operation fails, peer will still be added to SeenTable # and removed from PeerPool. So it will be not reused for syncing for # `SeenTablePenaltyError` time. asyncSpawn peer.disconnect(PeerScoreLow) except: discard false else: true node.network.peerPool.setScoreCheck(scoreCheck) node.syncManager = newSyncManager[Peer, PeerID]( node.network.peerPool, getLocalHeadSlot, getLocalWallSlot, getFirstSlotAtFinalizedEpoch, node.processor.blocksQueue, chunkSize = 32 ) node.syncManager.start() proc currentSlot(node: BeaconNode): Slot = node.beaconClock.now.slotOrZero proc connectedPeersCount(node: BeaconNode): int = len(node.network.peerPool) proc installBeaconApiHandlers(rpcServer: RpcServer, node: BeaconNode) = rpcServer.rpc("getBeaconHead") do () -> Slot: return node.chainDag.head.slot rpcServer.rpc("getChainHead") do () -> JsonNode: let head = node.chainDag.head finalized = node.chainDag.headState.data.data.finalized_checkpoint justified = node.chainDag.headState.data.data.current_justified_checkpoint return %* { "head_slot": head.slot, "head_block_root": head.root.data.toHex(), "finalized_slot": finalized.epoch * SLOTS_PER_EPOCH, "finalized_block_root": finalized.root.data.toHex(), "justified_slot": justified.epoch * SLOTS_PER_EPOCH, "justified_block_root": justified.root.data.toHex(), } rpcServer.rpc("getSyncing") do () -> bool: let wallSlot = currentSlot(node) headSlot = node.chainDag.head.slot # FIXME: temporary hack: If more than 1 block away from expected head, then we are "syncing" return (headSlot + 1) < wallSlot template requireOneOf(x, y: distinct Option) = if x.isNone xor y.isNone: raise newException(CatchableError, "Please specify one of " & astToStr(x) & " or " & astToStr(y)) template jsonResult(x: auto): auto = StringOfJson(Json.encode(x)) rpcServer.rpc("getBeaconBlock") do (slot: Option[Slot], root: Option[Eth2Digest]) -> StringOfJson: requireOneOf(slot, root) var blockHash: Eth2Digest if root.isSome: blockHash = root.get else: let foundRef = node.chainDag.getBlockByPreciseSlot(slot.get) if foundRef != nil: blockHash = foundRef.root else: return StringOfJson("null") let dbBlock = node.db.getBlock(blockHash) if dbBlock.isSome: return jsonResult(dbBlock.get) else: return StringOfJson("null") rpcServer.rpc("getBeaconState") do (slot: Option[Slot], root: Option[Eth2Digest]) -> StringOfJson: requireOneOf(slot, root) if slot.isSome: # TODO sanity check slot so that it doesn't cause excessive rewinding let blk = node.chainDag.head.atSlot(slot.get) node.chainDag.withState(node.chainDag.tmpState, blk): return jsonResult(state) else: let tmp = BeaconStateRef() # TODO use tmpState - but load the entire StateData! let state = node.db.getState(root.get, tmp[], noRollback) if state: return jsonResult(tmp[]) else: return StringOfJson("null") rpcServer.rpc("getNetworkPeerId") do () -> string: return $publicKey(node.network) rpcServer.rpc("getNetworkPeers") do () -> seq[string]: for peerId, peer in node.network.peerPool: result.add $peerId rpcServer.rpc("getNetworkEnr") do () -> string: return $node.network.discovery.localNode.record proc installDebugApiHandlers(rpcServer: RpcServer, node: BeaconNode) = rpcServer.rpc("getNodeVersion") do () -> string: return "Nimbus/" & fullVersionStr rpcServer.rpc("getSpecPreset") do () -> JsonNode: var res = newJObject() genStmtList: for presetValue in PresetValue: if presetValue notin ignoredValues + runtimeValues: let settingSym = ident($presetValue) settingKey = newLit(toLowerAscii($presetValue)) let f = quote do: res[`settingKey`] = %(presets.`settingSym`) yield f for field, value in fieldPairs(node.config.runtimePreset): res[field] = when value isnot Version: %value else: %value.toUInt64 return res rpcServer.rpc("peers") do () -> JsonNode: var res = newJObject() var peers = newJArray() for id, peer in node.network.peerPool: peers.add( %( info: shortLog(peer.info), connectionState: $peer.connectionState, score: peer.score, ) ) res.add("peers", peers) return res proc installRpcHandlers(rpcServer: RpcServer, node: BeaconNode) = rpcServer.installValidatorApiHandlers(node) rpcServer.installBeaconApiHandlers(node) rpcServer.installDebugApiHandlers(node) proc installMessageValidators(node: BeaconNode) = # https://github.com/ethereum/eth2.0-specs/blob/v0.12.3/specs/phase0/p2p-interface.md#attestations-and-aggregation # These validators stay around the whole time, regardless of which specific # subnets are subscribed to during any given epoch. for it in 0'u64 ..< ATTESTATION_SUBNET_COUNT.uint64: closureScope: let ci = it node.network.addValidator( getAttestationTopic(node.forkDigest, ci), # This proc needs to be within closureScope; don't lift out of loop. proc(attestation: Attestation): ValidationResult = node.processor[].attestationValidator(attestation, ci)) node.network.addValidator( getAggregateAndProofsTopic(node.forkDigest), proc(signedAggregateAndProof: SignedAggregateAndProof): ValidationResult = node.processor[].aggregateValidator(signedAggregateAndProof)) node.network.addValidator( node.topicBeaconBlocks, proc (signedBlock: SignedBeaconBlock): ValidationResult = node.processor[].blockValidator(signedBlock)) node.network.addValidator( getAttesterSlashingsTopic(node.forkDigest), proc (attesterSlashing: AttesterSlashing): ValidationResult = node.processor[].attesterSlashingValidator(attesterSlashing)) node.network.addValidator( getProposerSlashingsTopic(node.forkDigest), proc (proposerSlashing: ProposerSlashing): ValidationResult = node.processor[].proposerSlashingValidator(proposerSlashing)) node.network.addValidator( getVoluntaryExitsTopic(node.forkDigest), proc (signedVoluntaryExit: SignedVoluntaryExit): ValidationResult = node.processor[].voluntaryExitValidator(signedVoluntaryExit)) proc stop*(node: BeaconNode) = status = BeaconNodeStatus.Stopping info "Graceful shutdown" if not node.config.inProcessValidators: node.vcProcess.close() waitFor node.network.stop() node.db.close() info "Database closed" proc run*(node: BeaconNode) = if status == BeaconNodeStatus.Starting: # it might have been set to "Stopping" with Ctrl+C status = BeaconNodeStatus.Running if node.rpcServer != nil: node.rpcServer.installRpcHandlers(node) node.rpcServer.start() node.installMessageValidators() let curSlot = node.beaconClock.now().slotOrZero() nextSlot = curSlot + 1 # No earlier than GENESIS_SLOT + 1 fromNow = saturate(node.beaconClock.fromNow(nextSlot)) info "Scheduling first slot action", beaconTime = shortLog(node.beaconClock.now()), nextSlot = shortLog(nextSlot), fromNow = shortLog(fromNow) addTimer(fromNow) do (p: pointer): asyncCheck node.onSlotStart(curSlot, nextSlot) node.onSecondLoop = runOnSecondLoop(node) node.blockProcessingLoop = node.processor.runQueueProcessingLoop() node.requestManager.start() node.startSyncManager() # main event loop while status == BeaconNodeStatus.Running: try: poll() except CatchableError as e: debug "Exception in poll()", exc = e.name, err = e.msg # time to say goodbye node.stop() var gPidFile: string proc createPidFile(filename: string) = createDir splitFile(filename).dir writeFile filename, $os.getCurrentProcessId() gPidFile = filename addQuitProc proc {.noconv.} = removeFile gPidFile proc initializeNetworking(node: BeaconNode) {.async.} = await node.network.startListening() let addressFile = node.config.dataDir / "beacon_node.enr" writeFile(addressFile, node.network.announcedENR.toURI) await node.network.start() info "Networking initialized", enr = node.network.announcedENR.toURI, libp2p = shortLog(node.network.switch.peerInfo) proc start(node: BeaconNode) = let head = node.chainDag.head finalizedHead = node.chainDag.finalizedHead genesisTime = node.beaconClock.fromNow(toBeaconTime(Slot 0)) info "Starting beacon node", version = fullVersionStr, nim = shortNimBanner(), timeSinceFinalization = finalizedHead.slot.toBeaconTime() - node.beaconClock.now(), head = shortLog(head), finalizedHead = shortLog(finalizedHead), SLOTS_PER_EPOCH, SECONDS_PER_SLOT, SPEC_VERSION, dataDir = node.config.dataDir.string if genesisTime.inFuture: notice "Waiting for genesis", genesisIn = genesisTime.offset waitFor node.initializeNetworking() node.run() func formatGwei(amount: uint64): string = # TODO This is implemented in a quite a silly way. # Better routines for formatting decimal numbers # should exists somewhere else. let eth = amount div 1000000000 remainder = amount mod 1000000000 result = $eth if remainder != 0: result.add '.' result.add $remainder while result[^1] == '0': result.setLen(result.len - 1) when hasPrompt: from unicode import Rune import prompt func providePromptCompletions*(line: seq[Rune], cursorPos: int): seq[string] = # TODO # The completions should be generated with the general-purpose command-line # parsing API of Confutils result = @[] proc processPromptCommands(p: ptr Prompt) {.thread.} = while true: var cmd = p[].readLine() case cmd of "quit": quit 0 else: p[].writeLine("Unknown command: " & cmd) proc initPrompt(node: BeaconNode) = if isatty(stdout) and node.config.statusBarEnabled: enableTrueColors() # TODO: nim-prompt seems to have threading issues at the moment # which result in sporadic crashes. We should introduce a # lock that guards the access to the internal prompt line # variable. # # var p = Prompt.init("nimbus > ", providePromptCompletions) # p.useHistoryFile() proc dataResolver(expr: string): string = template justified: untyped = node.chainDag.head.atEpochStart( node.chainDag.headState.data.data.current_justified_checkpoint.epoch) # TODO: # We should introduce a general API for resolving dot expressions # such as `db.latest_block.slot` or `metrics.connected_peers`. # Such an API can be shared between the RPC back-end, CLI tools # such as ncli, a potential GraphQL back-end and so on. # The status bar feature would allow the user to specify an # arbitrary expression that is resolvable through this API. case expr.toLowerAscii of "connected_peers": $(node.connectedPeersCount) of "head_root": shortLog(node.chainDag.head.root) of "head_epoch": $(node.chainDag.head.slot.epoch) of "head_epoch_slot": $(node.chainDag.head.slot mod SLOTS_PER_EPOCH) of "head_slot": $(node.chainDag.head.slot) of "justifed_root": shortLog(justified.blck.root) of "justifed_epoch": $(justified.slot.epoch) of "justifed_epoch_slot": $(justified.slot mod SLOTS_PER_EPOCH) of "justifed_slot": $(justified.slot) of "finalized_root": shortLog(node.chainDag.finalizedHead.blck.root) of "finalized_epoch": $(node.chainDag.finalizedHead.slot.epoch) of "finalized_epoch_slot": $(node.chainDag.finalizedHead.slot mod SLOTS_PER_EPOCH) of "finalized_slot": $(node.chainDag.finalizedHead.slot) of "epoch": $node.currentSlot.epoch of "epoch_slot": $(node.currentSlot mod SLOTS_PER_EPOCH) of "slot": $node.currentSlot of "slots_per_epoch": $SLOTS_PER_EPOCH of "slot_trailing_digits": var slotStr = $node.currentSlot if slotStr.len > 3: slotStr = slotStr[^3..^1] slotStr of "attached_validators_balance": var balance = uint64(0) # TODO slow linear scan! for idx, b in node.chainDag.headState.data.data.balances: if node.getAttachedValidator( node.chainDag.headState.data.data, ValidatorIndex(idx)) != nil: balance += b formatGwei(balance) of "sync_status": if isNil(node.syncManager): "pending" else: if node.syncManager.inProgress: node.syncManager.syncStatus else: "synced" else: # We ignore typos for now and just render the expression # as it was written. TODO: come up with a good way to show # an error message to the user. "$" & expr var statusBar = StatusBarView.init( node.config.statusBarContents, dataResolver) when compiles(defaultChroniclesStream.output.writer): defaultChroniclesStream.output.writer = proc (logLevel: LogLevel, msg: LogOutputStr) {.raises: [Defect].} = try: # p.hidePrompt erase statusBar # p.writeLine msg stdout.write msg render statusBar # p.showPrompt except Exception as e: # render raises Exception logLoggingFailure(cstring(msg), e) proc statusBarUpdatesPollingLoop() {.async.} = while true: update statusBar await sleepAsync(chronos.seconds(1)) traceAsyncErrors statusBarUpdatesPollingLoop() # var t: Thread[ptr Prompt] # createThread(t, processPromptCommands, addr p) programMain: var config = makeBannerAndConfig(clientId, BeaconNodeConf) # This is ref so we can mutate it (to erase it) after the initial loading. stateSnapshotContents: ref string setupLogging(config.logLevel, config.logFile) if config.eth2Network.isSome: let metadata = getMetadataForNetwork(config.eth2Network.get) config.runtimePreset = metadata.runtimePreset if config.cmd == noCommand: for node in metadata.bootstrapNodes: config.bootstrapNodes.add node if config.stateSnapshot.isNone and metadata.genesisData.len > 0: stateSnapshotContents = newClone metadata.genesisData template checkForIncompatibleOption(flagName, fieldName) = # TODO: This will have to be reworked slightly when we introduce config files. # We'll need to keep track of the "origin" of the config value, so we can # discriminate between values from config files that can be overridden and # regular command-line options (that may conflict). if config.fieldName.isSome: fatal "Invalid CLI arguments specified. You must not specify '--network' and '" & flagName & "' at the same time", networkParam = config.eth2Network.get, `flagName` = config.fieldName.get quit 1 checkForIncompatibleOption "deposit-contract", depositContractAddress checkForIncompatibleOption "deposit-contract-block", depositContractDeployedAt config.depositContractAddress = some metadata.depositContractAddress config.depositContractDeployedAt = some metadata.depositContractDeployedAt else: config.runtimePreset = defaultRuntimePreset # Single RNG instance for the application - will be seeded on construction # and avoid using system resources (such as urandom) after that let rng = keys.newRng() case config.cmd of createTestnet: let launchPadDeposits = try: Json.loadFile(config.testnetDepositsFile.string, seq[LaunchPadDeposit]) except SerializationError as err: error "Invalid LaunchPad deposits file", err = formatMsg(err, config.testnetDepositsFile.string) quit 1 var deposits: seq[Deposit] for i in config.firstValidator.int ..< launchPadDeposits.len: deposits.add Deposit(data: launchPadDeposits[i] as DepositData) attachMerkleProofs(deposits) let startTime = uint64(times.toUnix(times.getTime()) + config.genesisOffset) outGenesis = config.outputGenesis.string eth1Hash = if config.web3Url.len == 0: eth1BlockHash else: (waitFor getEth1BlockHash(config.web3Url, blockId("latest"))).asEth2Digest var initialState = initialize_beacon_state_from_eth1( config.runtimePreset, eth1Hash, startTime, deposits, {skipBlsValidation}) # https://github.com/ethereum/eth2.0-pm/tree/6e41fcf383ebeb5125938850d8e9b4e9888389b4/interop/mocked_start#create-genesis-state initialState.genesis_time = startTime doAssert initialState.validators.len > 0 let outGenesisExt = splitFile(outGenesis).ext if cmpIgnoreCase(outGenesisExt, ".json") == 0: Json.saveFile(outGenesis, initialState, pretty = true) echo "Wrote ", outGenesis let outSszGenesis = outGenesis.changeFileExt "ssz" SSZ.saveFile(outSszGenesis, initialState[]) echo "Wrote ", outSszGenesis let bootstrapFile = config.outputBootstrapFile.string if bootstrapFile.len > 0: let networkKeys = getPersistentNetKeys(rng[], config) netMetadata = getPersistentNetMetadata(config) bootstrapEnr = enr.Record.init( 1, # sequence number networkKeys.seckey.asEthKey, some(config.bootstrapAddress), config.bootstrapPort, config.bootstrapPort, [toFieldPair("eth2", SSZ.encode(enrForkIdFromState initialState[])), toFieldPair("attnets", SSZ.encode(netMetadata.attnets))]) writeFile(bootstrapFile, bootstrapEnr.tryGet().toURI) echo "Wrote ", bootstrapFile of noCommand: debug "Launching beacon node", version = fullVersionStr, bls_backend = $BLS_BACKEND, cmdParams = commandLineParams(), config createPidFile(config.dataDir.string / "beacon_node.pid") config.createDumpDirs() ## Ctrl+C handling proc controlCHandler() {.noconv.} = when defined(windows): # workaround for https://github.com/nim-lang/Nim/issues/4057 setupForeignThreadGc() info "Shutting down after having received SIGINT" status = BeaconNodeStatus.Stopping setControlCHook(controlCHandler) when useInsecureFeatures: if config.metricsEnabled: let metricsAddress = config.metricsAddress info "Starting metrics HTTP server", address = metricsAddress, port = config.metricsPort metrics.startHttpServer($metricsAddress, config.metricsPort) var node = waitFor BeaconNode.init(rng, config, stateSnapshotContents) when hasPrompt: initPrompt(node) if node.nickname != "": dynamicLogScope(node = node.nickname): node.start() else: node.start() of deposits: case config.depositsCmd of DepositsCmd.create: var mnemonic: Mnemonic defer: burnMem(mnemonic) var walletPath: WalletPathPair if config.existingWalletId.isSome: let id = config.existingWalletId.get let found = keystore_management.findWallet(config, id) if found.isOk: walletPath = found.get else: fatal "Unable to find wallet with the specified name/uuid", id, err = found.error quit 1 var unlocked = unlockWalletInteractively(walletPath.wallet) if unlocked.isOk: swap(mnemonic, unlocked.get) else: # The failure will be reported in `unlockWalletInteractively`. quit 1 else: var walletRes = createWalletInteractively(rng[], config) if walletRes.isErr: fatal "Unable to create wallet", err = walletRes.error quit 1 else: swap(mnemonic, walletRes.get.mnemonic) walletPath = walletRes.get.walletPath createDir(config.outValidatorsDir) createDir(config.outSecretsDir) let deposits = generateDeposits( config.runtimePreset, rng[], mnemonic, walletPath.wallet.nextAccount, config.totalDeposits, config.outValidatorsDir, config.outSecretsDir) if deposits.isErr: fatal "Failed to generate deposits", err = deposits.error quit 1 try: let depositDataPath = if config.outDepositsFile.isSome: config.outDepositsFile.get.string else: config.outValidatorsDir / "deposit_data-" & $epochTime() & ".json" let launchPadDeposits = mapIt(deposits.value, LaunchPadDeposit.init(config.runtimePreset, it)) Json.saveFile(depositDataPath, launchPadDeposits) info "Deposit data written", filename = depositDataPath walletPath.wallet.nextAccount += deposits.value.len let status = saveWallet(walletPath) if status.isErr: error "Failed to update wallet file after generating deposits", wallet = walletPath.path, error = status.error quit 1 except CatchableError as err: error "Failed to create launchpad deposit data file", err = err.msg quit 1 of DepositsCmd.`import`: importKeystoresFromDir( rng[], config.importedDepositsDir.string, config.validatorsDir, config.secretsDir) of DepositsCmd.status: echo "The status command is not implemented yet" quit 1 of wallets: case config.walletsCmd: of WalletsCmd.create: var walletRes = createWalletInteractively(rng[], config) if walletRes.isErr: fatal "Unable to create wallet", err = walletRes.error quit 1 burnMem(walletRes.get.mnemonic) of WalletsCmd.list: for kind, walletFile in walkDir(config.walletsDir): if kind != pcFile: continue let walletRes = loadWallet(walletFile) if walletRes.isOk: echo walletRes.get.longName else: warn "Found corrupt wallet file", wallet = walletFile, error = walletRes.error of WalletsCmd.restore: restoreWalletInteractively(rng[], config)