nimbus-eth2/beacon_chain/spec/network.nim

208 lines
8.9 KiB
Nim

# beacon_chain
# Copyright (c) 2018-2022 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.
{.push raises: [Defect].}
# References to `vFuture` refer to the pre-release proposal of the libp2p based
# light client sync protocol. Conflicting release versions are not in use.
# https://github.com/ethereum/consensus-specs/pull/2802
import
"."/[helpers, forks],
"."/datatypes/base
export base
const
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.1/specs/phase0/p2p-interface.md#topics-and-messages
topicBeaconBlocksSuffix* = "beacon_block/ssz_snappy"
topicVoluntaryExitsSuffix* = "voluntary_exit/ssz_snappy"
topicProposerSlashingsSuffix* = "proposer_slashing/ssz_snappy"
topicAttesterSlashingsSuffix* = "attester_slashing/ssz_snappy"
topicAggregateAndProofsSuffix* = "beacon_aggregate_and_proof/ssz_snappy"
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.1/specs/phase0/p2p-interface.md#configuration
MAX_CHUNK_SIZE* = 1 * 1024 * 1024 # bytes
GOSSIP_MAX_SIZE* = 1 * 1024 * 1024 # bytes
TTFB_TIMEOUT* = 5.seconds
RESP_TIMEOUT* = 10.seconds
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.1/specs/bellatrix/p2p-interface.md#configuration
GOSSIP_MAX_SIZE_BELLATRIX* = 10 * 1024 * 1024 # bytes
MAX_CHUNK_SIZE_BELLATRIX* = 10 * 1024 * 1024 # bytes
defaultEth2TcpPort* = 9000
# This is not part of the spec! But its port which uses Lighthouse
DefaultEth2RestPort* = 5052
enrAttestationSubnetsField* = "attnets"
enrSyncSubnetsField* = "syncnets"
enrForkIdField* = "eth2"
template eth2Prefix(forkDigest: ForkDigest): string =
"/eth2/" & $forkDigest & "/"
func getBeaconBlocksTopic*(forkDigest: ForkDigest): string =
eth2Prefix(forkDigest) & topicBeaconBlocksSuffix
func getVoluntaryExitsTopic*(forkDigest: ForkDigest): string =
eth2Prefix(forkDigest) & topicVoluntaryExitsSuffix
func getProposerSlashingsTopic*(forkDigest: ForkDigest): string =
eth2Prefix(forkDigest) & topicProposerSlashingsSuffix
func getAttesterSlashingsTopic*(forkDigest: ForkDigest): string =
eth2Prefix(forkDigest) & topicAttesterSlashingsSuffix
func getAggregateAndProofsTopic*(forkDigest: ForkDigest): string =
eth2Prefix(forkDigest) & topicAggregateAndProofsSuffix
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.1/specs/phase0/validator.md#broadcast-attestation
func compute_subnet_for_attestation*(
committees_per_slot: uint64, slot: Slot, committee_index: CommitteeIndex):
SubnetId =
# Compute the correct subnet for an attestation for Phase 0.
# Note, this mimics expected Phase 1 behavior where attestations will be
# mapped to their shard subnet.
let
slots_since_epoch_start = slot.since_epoch_start()
committees_since_epoch_start =
committees_per_slot * slots_since_epoch_start
SubnetId(
(committees_since_epoch_start + committee_index.asUInt64) mod
ATTESTATION_SUBNET_COUNT)
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.1/specs/phase0/validator.md#broadcast-attestation
func getAttestationTopic*(forkDigest: ForkDigest,
subnetId: SubnetId): string =
## For subscribing and unsubscribing to/from a subnet.
eth2Prefix(forkDigest) & "beacon_attestation_" & $(subnetId) & "/ssz_snappy"
# https://github.com/ethereum/consensus-specs/blob/v1.1.10/specs/altair/p2p-interface.md#topics-and-messages
func getSyncCommitteeTopic*(forkDigest: ForkDigest,
subcommitteeIdx: SyncSubcommitteeIndex): string =
## For subscribing and unsubscribing to/from a subnet.
eth2Prefix(forkDigest) & "sync_committee_" & $subcommitteeIdx & "/ssz_snappy"
# https://github.com/ethereum/consensus-specs/blob/v1.1.10/specs/altair/p2p-interface.md#topics-and-messages
func getSyncCommitteeContributionAndProofTopic*(forkDigest: ForkDigest): string =
## For subscribing and unsubscribing to/from a subnet.
eth2Prefix(forkDigest) & "sync_committee_contribution_and_proof/ssz_snappy"
# https://github.com/ethereum/consensus-specs/blob/vFuture/specs/altair/sync-protocol.md#light_client_finality_update
func getLightClientFinalityUpdateTopic*(forkDigest: ForkDigest): string =
## For broadcasting or obtaining the latest `LightClientFinalityUpdate`.
eth2Prefix(forkDigest) & "light_client_finality_update_v0/ssz_snappy"
# https://github.com/ethereum/consensus-specs/blob/vFuture/specs/altair/sync-protocol.md#light_client_optimistic_update
func getLightClientOptimisticUpdateTopic*(forkDigest: ForkDigest): string =
## For broadcasting or obtaining the latest `LightClientOptimisticUpdate`.
eth2Prefix(forkDigest) & "light_client_optimistic_update_v0/ssz_snappy"
func getENRForkID*(cfg: RuntimeConfig,
epoch: Epoch,
genesis_validators_root: Eth2Digest): ENRForkID =
let
current_fork_version = cfg.forkVersionAtEpoch(epoch)
next_fork_version = if cfg.nextForkEpochAtEpoch(epoch) == FAR_FUTURE_EPOCH:
current_fork_version
else:
cfg.forkVersionAtEpoch(cfg.nextForkEpochAtEpoch(epoch))
fork_digest = compute_fork_digest(current_fork_version,
genesis_validators_root)
ENRForkID(
fork_digest: fork_digest,
next_fork_version: next_fork_version,
next_fork_epoch: cfg.nextForkEpochAtEpoch(epoch))
func getDiscoveryForkID*(cfg: RuntimeConfig,
epoch: Epoch,
genesis_validators_root: Eth2Digest): ENRForkID =
# Until 1 epoch from fork, returns pre-fork value
if epoch + 1 >= cfg.ALTAIR_FORK_EPOCH:
getENRForkID(cfg, epoch, genesis_validators_root)
else:
let
current_fork_version = cfg.forkVersionAtEpoch(epoch)
fork_digest = compute_fork_digest(current_fork_version,
genesis_validators_root)
ENRForkID(
fork_digest: fork_digest,
next_fork_version: current_fork_version,
next_fork_epoch: FAR_FUTURE_EPOCH)
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.1/specs/altair/p2p-interface.md#transitioning-the-gossip
type GossipState* = set[BeaconStateFork]
func getTargetGossipState*(
epoch, ALTAIR_FORK_EPOCH, BELLATRIX_FORK_EPOCH: Epoch, isBehind: bool):
GossipState =
if isBehind:
{}
# The order of these checks doesn't matter.
elif epoch >= BELLATRIX_FORK_EPOCH:
{BeaconStateFork.Bellatrix}
elif epoch + 1 < ALTAIR_FORK_EPOCH:
{BeaconStateFork.Phase0}
# Order remaining checks so ALTAIR_FORK_EPOCH == BELLATRIX_FORK_EPOCH works
# and when the transition zones align contiguously, or are separated by
# intermediate pure-Altair epochs.
#
# In the first case, should never enable Altair, and there's also never
# a Phase -> Altair, or Altair -> Bellatrix gossip transition epoch. In
# contiguous Phase0 -> Altair and Altair -> Bellatrix transitions, that
# pure Altair state gossip state never occurs, but it works without any
# special cases so long as one checks for transition-to-fork+1 before a
# pure fork gossip state.
#
# Therefore, check for transition-to-merge before pure-Altair.
elif epoch + 1 >= BELLATRIX_FORK_EPOCH:
# As there are only two fork epochs and there's no transition to phase0
{if ALTAIR_FORK_EPOCH == BELLATRIX_FORK_EPOCH:
BeaconStateFork.Phase0
else:
BeaconStateFork.Altair,
BeaconStateFork.Bellatrix}
elif epoch >= ALTAIR_FORK_EPOCH:
{BeaconStateFork.Altair}
# Must be after the case which catches phase0 => merge
elif epoch + 1 >= ALTAIR_FORK_EPOCH:
{BeaconStateFork.Phase0, BeaconStateFork.Altair}
else:
raiseAssert "Unknown target gossip state"
func nearSyncCommitteePeriod*(epoch: Epoch): Option[uint64] =
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.1/specs/altair/validator.md#sync-committee-subnet-stability
if epoch.is_sync_committee_period():
return some 0'u64
let epochsBefore =
EPOCHS_PER_SYNC_COMMITTEE_PERIOD - epoch.since_sync_committee_period_start()
if epoch.is_sync_committee_period() or epochsBefore <= SYNC_COMMITTEE_SUBNET_COUNT:
return some epochsBefore
none(uint64)
func getSyncSubnets*(
nodeHasPubkey: proc(pubkey: ValidatorPubKey):
bool {.noSideEffect, raises: [Defect].},
syncCommittee: SyncCommittee): SyncnetBits =
var res: SyncnetBits
for i, pubkey in syncCommittee.pubkeys:
if not nodeHasPubkey(pubkey):
continue
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.1/specs/altair/validator.md#broadcast-sync-committee-message
# The first quarter of the pubkeys map to subnet 0, the second quarter to
# subnet 1, the third quarter to subnet 2 and the final quarter to subnet
# 3.
res.setBit(i div (SYNC_COMMITTEE_SIZE div SYNC_COMMITTEE_SUBNET_COUNT))
res