nimbus-eth2/beacon_chain/networking/peer_protocol.nim

260 lines
9.3 KiB
Nim

# beacon_chain
# Copyright (c) 2018-2024 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: [].}
import
chronicles,
../spec/network,
".."/[beacon_clock],
../networking/eth2_network,
../consensus_object_pools/blockchain_dag,
../rpc/rest_constants
logScope:
topics = "peer_proto"
type
StatusMsg* = object
forkDigest*: ForkDigest
finalizedRoot*: Eth2Digest
finalizedEpoch*: Epoch
headRoot*: Eth2Digest
headSlot*: Slot
PeerSyncNetworkState* {.final.} = ref object of RootObj
dag: ChainDAGRef
cfg: RuntimeConfig
forkDigests: ref ForkDigests
genesisBlockRoot: Eth2Digest
getBeaconTime: GetBeaconTimeFn
PeerSyncPeerState* {.final.} = ref object of RootObj
statusLastTime: chronos.Moment
statusMsg: StatusMsg
func shortLog*(s: StatusMsg): auto =
(
forkDigest: s.forkDigest,
finalizedRoot: shortLog(s.finalizedRoot),
finalizedEpoch: shortLog(s.finalizedEpoch),
headRoot: shortLog(s.headRoot),
headSlot: shortLog(s.headSlot)
)
chronicles.formatIt(StatusMsg): shortLog(it)
func disconnectReasonName(reason: uint64): string =
# haha, nim doesn't support uint64 in `case`!
if reason == uint64(ClientShutDown): "Client shutdown"
elif reason == uint64(IrrelevantNetwork): "Irrelevant network"
elif reason == uint64(FaultOrError): "Fault or error"
else: "Disconnected (" & $reason & ")"
func forkDigestAtEpoch(state: PeerSyncNetworkState,
epoch: Epoch): ForkDigest =
state.forkDigests[].atEpoch(epoch, state.cfg)
# https://github.com/ethereum/consensus-specs/blob/v1.4.0/specs/phase0/p2p-interface.md#status
proc getCurrentStatus(state: PeerSyncNetworkState): StatusMsg =
let
dag = state.dag
wallSlot = state.getBeaconTime().slotOrZero
if dag != nil:
StatusMsg(
forkDigest: state.forkDigestAtEpoch(wallSlot.epoch),
finalizedRoot:
(if dag.finalizedHead.slot.epoch != GENESIS_EPOCH:
dag.finalizedHead.blck.root
else:
# this defaults to `Root(b'\x00' * 32)` for the genesis finalized
# checkpoint
ZERO_HASH),
finalizedEpoch: dag.finalizedHead.slot.epoch,
headRoot: dag.head.root,
headSlot: dag.head.slot)
else:
StatusMsg(
forkDigest: state.forkDigestAtEpoch(wallSlot.epoch),
# this defaults to `Root(b'\x00' * 32)` for the genesis finalized
# checkpoint
finalizedRoot: ZERO_HASH,
finalizedEpoch: GENESIS_EPOCH,
headRoot: state.genesisBlockRoot,
headSlot: GENESIS_SLOT)
proc checkStatusMsg(state: PeerSyncNetworkState, status: StatusMsg):
Result[void, cstring] =
let
dag = state.dag
wallSlot = (state.getBeaconTime() + MAXIMUM_GOSSIP_CLOCK_DISPARITY).slotOrZero
if status.finalizedEpoch > status.headSlot.epoch:
# Can be equal during genesis or checkpoint start
return err("finalized epoch newer than head")
if status.headSlot > wallSlot:
return err("head more recent than wall clock")
if state.forkDigestAtEpoch(wallSlot.epoch) != status.forkDigest:
return err("fork digests differ")
# https://github.com/ethereum/consensus-specs/blob/v1.4.0/specs/phase0/p2p-interface.md#status
if dag != nil:
if status.finalizedEpoch <= dag.finalizedHead.slot.epoch:
let blockId = dag.getBlockIdAtSlot(status.finalizedEpoch.start_slot())
if blockId.isSome and
(not status.finalizedRoot.isZero) and
status.finalizedRoot != blockId.get().bid.root:
return err("peer following different finality")
else:
if status.finalizedEpoch == GENESIS_EPOCH:
# "this defaults to `Root(b'\x00' * 32)` for the genesis finalized checkpoint"
# keep compatibility with Lighthouse and other Nimbus for a while, which
# apparently don't use spec ZERO_HASH as of this writing
if not (status.finalizedRoot in [state.genesisBlockRoot, ZERO_HASH]):
return err("peer following different finality")
ok()
proc handleStatus(peer: Peer,
state: PeerSyncNetworkState,
theirStatus: StatusMsg): Future[bool] {.async: (raises: [CancelledError]).}
{.pop.} # TODO fix p2p macro for raises
p2pProtocol PeerSync(version = 1,
networkState = PeerSyncNetworkState,
peerState = PeerSyncPeerState):
onPeerConnected do (peer: Peer, incoming: bool) {.async: (raises: [CancelledError]).}:
debug "Peer connected",
peer, peerId = shortLog(peer.peerId), incoming
# Per the eth2 protocol, whoever dials must send a status message when
# connected for the first time, but because of how libp2p works, there may
# be a race between incoming and outgoing connections and disconnects that
# makes the incoming flag unreliable / obsolete by the time we get to
# this point - instead of making assumptions, we'll just send a status
# message redundantly.
# TODO(zah)
# the spec does not prohibit sending the extra status message on
# incoming connections, but it should not be necessary - this would
# need a dedicated flow in libp2p that resolves the race conditions -
# this needs more thinking around the ordering of events and the
# given incoming flag
let
ourStatus = peer.networkState.getCurrentStatus()
theirStatus = await peer.status(ourStatus, timeout = RESP_TIMEOUT_DUR)
if theirStatus.isOk:
discard await peer.handleStatus(peer.networkState, theirStatus.get())
else:
debug "Status response not received in time",
peer, errorKind = theirStatus.error.kind
await peer.disconnect(FaultOrError)
proc status(peer: Peer,
theirStatus: StatusMsg,
response: SingleChunkResponse[StatusMsg])
{.async, libp2pProtocol("status", 1).} =
let ourStatus = peer.networkState.getCurrentStatus()
trace "Sending status message", peer = peer, status = ourStatus
await response.send(ourStatus)
discard await peer.handleStatus(peer.networkState, theirStatus)
proc ping(peer: Peer, value: uint64): uint64
{.libp2pProtocol("ping", 1).} =
peer.network.metadata.seq_number
# https://github.com/ethereum/consensus-specs/blob/v1.4.0/specs/altair/p2p-interface.md#transitioning-from-v1-to-v2
proc getMetaData(peer: Peer): uint64
{.libp2pProtocol("metadata", 1).} =
raise newException(InvalidInputsError, "GetMetaData v1 unsupported")
proc getMetadata_v2(peer: Peer): altair.MetaData
{.libp2pProtocol("metadata", 2).} =
peer.network.metadata
proc goodbye(peer: Peer, reason: uint64)
{.async, libp2pProtocol("goodbye", 1).} =
debug "Received Goodbye message", reason = disconnectReasonName(reason), peer
proc setStatusMsg(peer: Peer, statusMsg: StatusMsg) =
debug "Peer status", peer, statusMsg
peer.state(PeerSync).statusMsg = statusMsg
peer.state(PeerSync).statusLastTime = Moment.now()
proc handleStatus(peer: Peer,
state: PeerSyncNetworkState,
theirStatus: StatusMsg): Future[bool]
{.async: (raises: [CancelledError]).} =
let
res = checkStatusMsg(state, theirStatus)
return if res.isErr():
debug "Irrelevant peer", peer, theirStatus, err = res.error()
await peer.disconnect(IrrelevantNetwork)
false
else:
peer.setStatusMsg(theirStatus)
if peer.connectionState == Connecting:
# As soon as we get here it means that we passed handshake succesfully. So
# we can add this peer to PeerPool.
await peer.handlePeer()
true
proc updateStatus*(peer: Peer): Future[bool] {.async: (raises: [CancelledError]).} =
## Request `status` of remote peer ``peer``.
let
nstate = peer.networkState(PeerSync)
ourStatus = getCurrentStatus(nstate)
theirStatus =
(await peer.status(ourStatus, timeout = RESP_TIMEOUT_DUR)).valueOr:
return false
await peer.handleStatus(nstate, theirStatus)
proc getHeadRoot*(peer: Peer): Eth2Digest =
## Returns head root for specific peer ``peer``.
peer.state(PeerSync).statusMsg.headRoot
proc getHeadSlot*(peer: Peer): Slot =
## Returns head slot for specific peer ``peer``.
peer.state(PeerSync).statusMsg.headSlot
proc getFinalizedEpoch*(peer: Peer): Epoch =
## Returns head slot for specific peer ``peer``.
peer.state(PeerSync).statusMsg.finalizedEpoch
proc getStatusLastTime*(peer: Peer): chronos.Moment =
## Returns head slot for specific peer ``peer``.
peer.state(PeerSync).statusLastTime
proc init*(T: type PeerSync.NetworkState,
dag: ChainDAGRef, getBeaconTime: GetBeaconTimeFn): T =
T(
dag: dag,
cfg: dag.cfg,
forkDigests: dag.forkDigests,
genesisBlockRoot: dag.genesisBlockRoot,
getBeaconTime: getBeaconTime,
)
proc init*(T: type PeerSync.NetworkState,
cfg: RuntimeConfig,
forkDigests: ref ForkDigests,
genesisBlockRoot: Eth2Digest,
getBeaconTime: GetBeaconTimeFn): T =
T(
dag: nil,
cfg: cfg,
forkDigests: forkDigests,
genesisBlockRoot: genesisBlockRoot,
getBeaconTime: getBeaconTime,
)