523 lines
22 KiB
Nim
523 lines
22 KiB
Nim
# 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
|
|
os, tables, strutils,
|
|
|
|
# Nimble packages
|
|
stew/[byteutils, objects], stew/shims/macros,
|
|
chronos, metrics, json_rpc/[rpcserver, jsonmarshal],
|
|
chronicles,
|
|
json_serialization/std/[options, sets, net], serialization/errors,
|
|
eth/db/kvstore,
|
|
eth/[keys, async_utils], eth/p2p/discoveryv5/[protocol, enr],
|
|
|
|
# Local modules
|
|
spec/[datatypes, digest, crypto, beaconstate, helpers, validator, network],
|
|
spec/state_transition,
|
|
conf, time, validator_pool,
|
|
attestation_pool, block_pool, block_pools/candidate_chains, eth2_network,
|
|
keystore_management, beacon_node_common, beacon_node_types,
|
|
nimbus_binary_common, mainchain_monitor, version, ssz/merkleization, interop,
|
|
attestation_aggregation, sync_manager, sszdump
|
|
|
|
# Metrics for tracking attestation and beacon block loss
|
|
declareCounter beacon_attestations_sent,
|
|
"Number of beacon chain attestations sent by this peer"
|
|
declareCounter beacon_blocks_proposed,
|
|
"Number of beacon chain blocks sent by this peer"
|
|
|
|
logScope: topics = "beacval"
|
|
|
|
proc saveValidatorKey*(keyName, key: string, conf: BeaconNodeConf) =
|
|
let validatorsDir = conf.validatorsDir
|
|
let outputFile = validatorsDir / keyName
|
|
createDir validatorsDir
|
|
writeFile(outputFile, key)
|
|
info "Imported validator key", file = outputFile
|
|
|
|
proc addLocalValidator*(node: BeaconNode,
|
|
state: BeaconState,
|
|
privKey: ValidatorPrivKey) =
|
|
let pubKey = privKey.toPubKey()
|
|
|
|
let idx = state.validators.asSeq.findIt(it.pubKey == pubKey)
|
|
if idx == -1:
|
|
# We allow adding a validator even if its key is not in the state registry:
|
|
# it might be that the deposit for this validator has not yet been processed
|
|
warn "Validator not in registry (yet?)", pubKey
|
|
|
|
node.attachedValidators.addLocalValidator(pubKey, privKey)
|
|
|
|
proc addLocalValidators*(node: BeaconNode) {.async.} =
|
|
let
|
|
head = node.blockPool.head
|
|
bs = BlockSlot(blck: head.blck, slot: head.blck.slot)
|
|
|
|
node.blockPool.withState(node.blockPool.tmpState, bs):
|
|
for validatorKey in node.config.validatorKeys:
|
|
node.addLocalValidator state, validatorKey
|
|
# Allow some network events to be processed:
|
|
await sleepAsync(0.seconds)
|
|
|
|
info "Local validators attached ", count = node.attachedValidators.count
|
|
|
|
func getAttachedValidator*(node: BeaconNode,
|
|
state: BeaconState,
|
|
idx: ValidatorIndex): AttachedValidator =
|
|
let validatorKey = state.validators[idx].pubkey
|
|
node.attachedValidators.getValidator(validatorKey)
|
|
|
|
proc isSynced*(node: BeaconNode, head: BlockRef): bool =
|
|
## TODO This function is here as a placeholder for some better heurestics to
|
|
## determine if we're in sync and should be producing blocks and
|
|
## attestations. Generally, the problem is that slot time keeps advancing
|
|
## even when there are no blocks being produced, so there's no way to
|
|
## distinguish validators geniunely going missing from the node not being
|
|
## well connected (during a network split or an internet outage for
|
|
## example). It would generally be correct to simply keep running as if
|
|
## we were the only legit node left alive, but then we run into issues:
|
|
## with enough many empty slots, the validator pool is emptied leading
|
|
## to empty committees and lots of empty slot processing that will be
|
|
## thrown away as soon as we're synced again.
|
|
|
|
let
|
|
# The slot we should be at, according to the clock
|
|
beaconTime = node.beaconClock.now()
|
|
wallSlot = beaconTime.toSlot()
|
|
|
|
# TODO if everyone follows this logic, the network will not recover from a
|
|
# halt: nobody will be producing blocks because everone expects someone
|
|
# else to do it
|
|
if wallSlot.afterGenesis and head.slot + MaxEmptySlotCount < wallSlot.slot:
|
|
false
|
|
else:
|
|
true
|
|
|
|
proc sendAttestation*(
|
|
node: BeaconNode, attestation: Attestation, num_active_validators: uint64) =
|
|
logScope: pcs = "send_attestation"
|
|
|
|
# https://github.com/ethereum/eth2.0-specs/blob/v0.12.1/specs/phase0/p2p-interface.md#attestations-and-aggregation
|
|
node.network.broadcast(
|
|
getAttestationTopic(node.forkDigest, attestation, num_active_validators),
|
|
attestation)
|
|
|
|
beacon_attestations_sent.inc()
|
|
|
|
proc sendAttestation*(node: BeaconNode, attestation: Attestation) =
|
|
# For the validator API, which doesn't supply num_active_validators.
|
|
let attestationBlck =
|
|
node.blockPool.getRef(attestation.data.beacon_block_root)
|
|
if attestationBlck.isNil:
|
|
debug "Attempt to send attestation without corresponding block"
|
|
return
|
|
|
|
node.blockPool.withEpochState(
|
|
node.blockPool.tmpState,
|
|
BlockSlot(blck: attestationBlck, slot: attestation.data.slot)):
|
|
node.sendAttestation(
|
|
attestation,
|
|
blck.getEpochInfo(state).shuffled_active_validator_indices.len.uint64)
|
|
|
|
proc createAndSendAttestation(node: BeaconNode,
|
|
fork: Fork,
|
|
genesis_validators_root: Eth2Digest,
|
|
validator: AttachedValidator,
|
|
attestationData: AttestationData,
|
|
committeeLen: int,
|
|
indexInCommittee: int,
|
|
num_active_validators: uint64) {.async.} =
|
|
logScope: pcs = "send_attestation"
|
|
|
|
var attestation = await validator.produceAndSignAttestation(attestationData, committeeLen, indexInCommittee, fork, genesis_validators_root)
|
|
|
|
node.sendAttestation(attestation, num_active_validators)
|
|
|
|
if node.config.dumpEnabled:
|
|
dump(node.config.dumpDirOutgoing, attestation.data, validator.pubKey)
|
|
|
|
info "Attestation sent",
|
|
attestation = shortLog(attestation),
|
|
validator = shortLog(validator),
|
|
indexInCommittee = indexInCommittee,
|
|
cat = "consensus"
|
|
|
|
type
|
|
ValidatorInfoForMakeBeaconBlockKind* = enum
|
|
viValidator
|
|
viRandao_reveal
|
|
ValidatorInfoForMakeBeaconBlock* = object
|
|
case kind*: ValidatorInfoForMakeBeaconBlockKind
|
|
of viValidator: validator*: AttachedValidator
|
|
of viRandao_reveal: randao_reveal*: ValidatorSig
|
|
|
|
proc makeBeaconBlockForHeadAndSlot*(node: BeaconNode,
|
|
val_info: ValidatorInfoForMakeBeaconBlock,
|
|
validator_index: ValidatorIndex,
|
|
graffiti: Eth2Digest,
|
|
head: BlockRef,
|
|
slot: Slot):
|
|
tuple[message: Option[BeaconBlock], fork: Fork, genesis_validators_root: Eth2Digest] =
|
|
# Advance state to the slot that we're proposing for - this is the equivalent
|
|
# of running `process_slots` up to the slot of the new block.
|
|
node.blockPool.withState(
|
|
node.blockPool.tmpState, head.atSlot(slot)):
|
|
let (eth1data, deposits) =
|
|
if node.mainchainMonitor.isNil:
|
|
(get_eth1data_stub(state.eth1_deposit_index, slot.compute_epoch_at_slot()),
|
|
newSeq[Deposit]())
|
|
else:
|
|
node.mainchainMonitor.getBlockProposalData(state)
|
|
|
|
# TODO perhaps just making the enclosing function accept 2 different types at the
|
|
# same time and doing some compile-time branching logic is cleaner (without the
|
|
# need for the discriminated union)... but we need the `state` from `withState`
|
|
# in order to get the fork/root for the specific head/slot for the randao_reveal
|
|
# and it's causing problems when the function becomes a generic for 2 types...
|
|
proc getRandaoReveal(val_info: ValidatorInfoForMakeBeaconBlock): ValidatorSig =
|
|
if val_info.kind == viValidator:
|
|
return val_info.validator.genRandaoReveal(state.fork, state.genesis_validators_root, slot)
|
|
elif val_info.kind == viRandao_reveal:
|
|
return val_info.randao_reveal
|
|
|
|
let
|
|
poolPtr = unsafeAddr node.blockPool.dag # safe because restore is short-lived
|
|
|
|
func restore(v: var HashedBeaconState) =
|
|
# TODO address this ugly workaround - there should probably be a
|
|
# `state_transition` that takes a `StateData` instead and updates
|
|
# the block as well
|
|
doAssert v.addr == addr poolPtr.tmpState.data
|
|
assign(poolPtr.tmpState, poolPtr.headState)
|
|
|
|
var cache = get_empty_per_epoch_cache()
|
|
let message = makeBeaconBlock(
|
|
node.config.runtimePreset,
|
|
hashedState,
|
|
validator_index,
|
|
head.root,
|
|
getRandaoReveal(val_info),
|
|
eth1data,
|
|
graffiti,
|
|
node.attestationPool.getAttestationsForBlock(state),
|
|
deposits,
|
|
restore,
|
|
cache)
|
|
|
|
if message.isSome():
|
|
# TODO this restore is needed because otherwise tmpState will be internally
|
|
# inconsistent - it's blck will not be pointing to the block that
|
|
# created this state - we have to reset it here before `await` to avoid
|
|
# races.
|
|
restore(poolPtr.tmpState.data)
|
|
|
|
return (message, state.fork, state.genesis_validators_root)
|
|
|
|
proc proposeSignedBlock*(node: BeaconNode,
|
|
head: BlockRef,
|
|
validator: AttachedValidator,
|
|
newBlock: SignedBeaconBlock,
|
|
blockRoot: Eth2Digest): Future[BlockRef] {.async.} =
|
|
|
|
{.gcsafe.}: # TODO: fork choice and blockpool should sync via messages instead of callbacks
|
|
let newBlockRef = node.blockPool.addRawBlock(blockRoot, newBlock) do (validBlock: BlockRef):
|
|
# Callback Add to fork choice
|
|
# node.attestationPool.addForkChoice_v2(validBlock)
|
|
discard "TODO: Deactivated"
|
|
|
|
if newBlockRef.isErr:
|
|
warn "Unable to add proposed block to block pool",
|
|
newBlock = shortLog(newBlock.message),
|
|
blockRoot = shortLog(blockRoot),
|
|
cat = "bug"
|
|
|
|
return head
|
|
|
|
info "Block proposed",
|
|
blck = shortLog(newBlock.message),
|
|
blockRoot = shortLog(newBlockRef[].root),
|
|
validator = shortLog(validator),
|
|
cat = "consensus"
|
|
|
|
if node.config.dumpEnabled:
|
|
dump(node.config.dumpDirOutgoing, newBlock, newBlockRef[])
|
|
|
|
node.network.broadcast(node.topicBeaconBlocks, newBlock)
|
|
|
|
beacon_blocks_proposed.inc()
|
|
|
|
return newBlockRef[]
|
|
|
|
proc proposeBlock(node: BeaconNode,
|
|
validator: AttachedValidator,
|
|
validator_index: ValidatorIndex,
|
|
head: BlockRef,
|
|
slot: Slot): Future[BlockRef] {.async.} =
|
|
logScope: pcs = "block_proposal"
|
|
|
|
if head.slot >= slot:
|
|
# We should normally not have a head newer than the slot we're proposing for
|
|
# but this can happen if block proposal is delayed
|
|
warn "Skipping proposal, have newer head already",
|
|
headSlot = shortLog(head.slot),
|
|
headBlockRoot = shortLog(head.root),
|
|
slot = shortLog(slot),
|
|
cat = "fastforward"
|
|
return head
|
|
|
|
var graffiti: Eth2Digest
|
|
graffiti.data[0..<5] = toBytes("quack")
|
|
let valInfo = ValidatorInfoForMakeBeaconBlock(kind: viValidator, validator: validator)
|
|
let beaconBlockTuple = makeBeaconBlockForHeadAndSlot(node, valInfo, validator_index, graffiti, head, slot)
|
|
|
|
if not beaconBlockTuple.message.isSome():
|
|
return head # already logged elsewhere!
|
|
var
|
|
newBlock = SignedBeaconBlock(
|
|
message: beaconBlockTuple.message.get()
|
|
)
|
|
|
|
let blockRoot = hash_tree_root(newBlock.message)
|
|
|
|
newBlock.signature = await validator.signBlockProposal(
|
|
beaconBlockTuple.fork, beaconBlockTuple.genesis_validators_root, slot, blockRoot)
|
|
|
|
return await node.proposeSignedBlock(head, validator, newBlock, blockRoot)
|
|
|
|
proc handleAttestations(node: BeaconNode, head: BlockRef, slot: Slot) =
|
|
## Perform all attestations that the validators attached to this node should
|
|
## perform during the given slot
|
|
logScope: pcs = "on_attestation"
|
|
|
|
if slot + SLOTS_PER_EPOCH < head.slot:
|
|
# The latest block we know about is a lot newer than the slot we're being
|
|
# asked to attest to - this makes it unlikely that it will be included
|
|
# at all.
|
|
# TODO the oldest attestations allowed are those that are older than the
|
|
# finalized epoch.. also, it seems that posting very old attestations
|
|
# is risky from a slashing perspective. More work is needed here.
|
|
notice "Skipping attestation, head is too recent",
|
|
headSlot = shortLog(head.slot),
|
|
slot = shortLog(slot)
|
|
return
|
|
|
|
let attestationHead = head.atSlot(slot)
|
|
if head != attestationHead.blck:
|
|
# In rare cases, such as when we're busy syncing or just slow, we'll be
|
|
# attesting to a past state - we must then recreate the world as it looked
|
|
# like back then
|
|
notice "Attesting to a state in the past, falling behind?",
|
|
headSlot = shortLog(head.slot),
|
|
attestationHeadSlot = shortLog(attestationHead.slot),
|
|
attestationSlot = shortLog(slot)
|
|
|
|
trace "Checking attestations",
|
|
attestationHeadRoot = shortLog(attestationHead.blck.root),
|
|
attestationSlot = shortLog(slot),
|
|
cat = "attestation"
|
|
|
|
# Collect data to send before node.stateCache grows stale
|
|
var attestations: seq[tuple[
|
|
data: AttestationData, committeeLen, indexInCommittee: int,
|
|
validator: AttachedValidator]]
|
|
|
|
# We need to run attestations exactly for the slot that we're attesting to.
|
|
# In case blocks went missing, this means advancing past the latest block
|
|
# using empty slots as fillers.
|
|
# https://github.com/ethereum/eth2.0-specs/blob/v0.12.1/specs/phase0/validator.md#validator-assignments
|
|
# TODO we could cache the validator assignment since it's valid for the entire
|
|
# epoch since it doesn't change, but that has to be weighed against
|
|
# the complexity of handling forks correctly - instead, we use an adapted
|
|
# version here that calculates the committee for a single slot only
|
|
node.blockPool.withState(node.blockPool.tmpState, attestationHead):
|
|
var cache = getEpochCache(attestationHead.blck, state)
|
|
let
|
|
committees_per_slot = get_committee_count_at_slot(state, slot)
|
|
num_active_validators =
|
|
try:
|
|
cache.shuffled_active_validator_indices[
|
|
slot.compute_epoch_at_slot].len.uint64
|
|
except KeyError:
|
|
raiseAssert "getEpochCache(...) didn't fill cache"
|
|
|
|
for committee_index in 0'u64..<committees_per_slot:
|
|
let committee = get_beacon_committee(
|
|
state, slot, committee_index.CommitteeIndex, cache)
|
|
|
|
for index_in_committee, validatorIdx in committee:
|
|
let validator = node.getAttachedValidator(state, validatorIdx)
|
|
if validator != nil:
|
|
let ad = makeAttestationData(state, slot, committee_index, blck.root)
|
|
attestations.add((ad, committee.len, index_in_committee, validator))
|
|
|
|
for a in attestations:
|
|
traceAsyncErrors createAndSendAttestation(
|
|
node, state.fork, state.genesis_validators_root, a.validator, a.data,
|
|
a.committeeLen, a.indexInCommittee, num_active_validators)
|
|
|
|
proc handleProposal(node: BeaconNode, head: BlockRef, slot: Slot):
|
|
Future[BlockRef] {.async.} =
|
|
## Perform the proposal for the given slot, iff we have a validator attached
|
|
## that is supposed to do so, given the shuffling in head
|
|
|
|
# TODO here we advance the state to the new slot, but later we'll be
|
|
# proposing for it - basically, we're selecting proposer based on an
|
|
# empty slot
|
|
|
|
let proposer = node.blockPool.getProposer(head, slot)
|
|
if proposer.isNone():
|
|
return head
|
|
|
|
let validator = node.attachedValidators.getValidator(proposer.get()[1])
|
|
|
|
if validator != nil:
|
|
return await proposeBlock(node, validator, proposer.get()[0], head, slot)
|
|
|
|
debug "Expecting block proposal",
|
|
headRoot = shortLog(head.root),
|
|
slot = shortLog(slot),
|
|
proposer_index = proposer.get()[0],
|
|
proposer = shortLog(proposer.get()[1]),
|
|
cat = "consensus",
|
|
pcs = "wait_for_proposal"
|
|
|
|
return head
|
|
|
|
proc broadcastAggregatedAttestations(
|
|
node: BeaconNode, aggregationHead: BlockRef, aggregationSlot: Slot,
|
|
trailing_distance: uint64) =
|
|
# 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 bs = BlockSlot(blck: aggregationHead, slot: aggregationSlot)
|
|
node.blockPool.withState(node.blockPool.tmpState, bs):
|
|
let
|
|
committees_per_slot = get_committee_count_at_slot(state, aggregationSlot)
|
|
var cache = get_empty_per_epoch_cache()
|
|
for committee_index in 0'u64..<committees_per_slot:
|
|
let committee = get_beacon_committee(
|
|
state, aggregationSlot, committee_index.CommitteeIndex, cache)
|
|
|
|
for index_in_committee, validatorIdx in committee:
|
|
let validator = node.getAttachedValidator(state, validatorIdx)
|
|
if validator != nil:
|
|
# This is slightly strange/inverted control flow, since really it's
|
|
# going to happen once per slot, but this is the best way to get at
|
|
# the validator index and private key pair. TODO verify it only has
|
|
# one isSome() with test.
|
|
let aggregateAndProof =
|
|
aggregate_attestations(node.attestationPool, state,
|
|
committee_index.CommitteeIndex,
|
|
# TODO https://github.com/status-im/nim-beacon-chain/issues/545
|
|
# this assumes in-process private keys
|
|
validator.privKey,
|
|
trailing_distance)
|
|
|
|
# Don't broadcast when, e.g., this node isn't an aggregator
|
|
if aggregateAndProof.isSome:
|
|
var signedAP = SignedAggregateAndProof(
|
|
message: aggregateAndProof.get,
|
|
# TODO Make the signing async here
|
|
signature: validator.signAggregateAndProof(
|
|
aggregateAndProof.get, state.fork,
|
|
state.genesis_validators_root))
|
|
node.network.broadcast(node.topicAggregateAndProofs, signedAP)
|
|
|
|
proc handleValidatorDuties*(
|
|
node: BeaconNode, lastSlot, slot: Slot) {.async.} =
|
|
## Perform validator duties - create blocks, vote and aggreagte existing votes
|
|
var head = node.updateHead()
|
|
if node.attachedValidators.count == 0:
|
|
# Nothing to do because we have no validator attached
|
|
return
|
|
|
|
if not node.isSynced(head):
|
|
notice "Node out of sync, skipping validator duties",
|
|
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:
|
|
# TODO maybe even collect all work synchronously to avoid unnecessary
|
|
# state rewinds while waiting for async operations like validator
|
|
# signature..
|
|
notice "Catching up",
|
|
curSlot = shortLog(curSlot),
|
|
lastSlot = shortLog(lastSlot),
|
|
slot = shortLog(slot),
|
|
cat = "overload"
|
|
|
|
# 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
|
|
# TODO what if we receive blocks / attestations while doing this work?
|
|
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
|
|
# TODO smells like there's an optimization opportunity here
|
|
handleAttestations(node, head, curSlot)
|
|
|
|
curSlot += 1
|
|
|
|
head = await handleProposal(node, head, 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..
|
|
|
|
# https://github.com/ethereum/eth2.0-specs/blob/v0.12.1/specs/phase0/validator.md#attesting
|
|
# A validator should create and broadcast the attestation to the associated
|
|
# attestation subnet when either (a) the validator has received a valid
|
|
# block from the expected block proposer for the assigned slot or
|
|
# (b) one-third of the slot has transpired (`SECONDS_PER_SLOT / 3` seconds
|
|
# after the start of slot) -- whichever comes first.
|
|
template sleepToSlotOffsetWithHeadUpdate(extra: chronos.Duration, msg: static string) =
|
|
if await node.beaconClock.sleepToSlotOffset(extra, slot, msg):
|
|
# Time passed - we might need to select a new head in that case
|
|
head = node.updateHead()
|
|
|
|
sleepToSlotOffsetWithHeadUpdate(
|
|
seconds(int64(SECONDS_PER_SLOT)) div 3, "Waiting to send attestations")
|
|
|
|
handleAttestations(node, head, slot)
|
|
|
|
# https://github.com/ethereum/eth2.0-specs/blob/v0.12.1/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:
|
|
sleepToSlotOffsetWithHeadUpdate(
|
|
seconds(int64(SECONDS_PER_SLOT * 2) div 3),
|
|
"Waiting to aggregate attestations")
|
|
|
|
const TRAILING_DISTANCE = 1
|
|
let
|
|
aggregationSlot = slot - TRAILING_DISTANCE
|
|
aggregationHead = getAncestorAt(head, aggregationSlot)
|
|
|
|
broadcastAggregatedAttestations(
|
|
node, aggregationHead, aggregationSlot, TRAILING_DISTANCE)
|