nimbus-eth2/beacon_chain/networking/eth2_discovery.nim

187 lines
6.3 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
std/[algorithm, sequtils],
chronos, chronicles, stew/results,
eth/p2p/discoveryv5/[enr, protocol, node, random2],
../spec/datatypes/altair,
../spec/eth2_ssz_serialization,
".."/[conf, conf_light_client]
from std/os import splitFile
from std/strutils import cmpIgnoreCase, split, startsWith, strip, toLowerAscii
export protocol, node
type
Eth2DiscoveryProtocol* = protocol.Protocol
Eth2DiscoveryId* = NodeId
func parseBootstrapAddress*(address: string):
Result[enr.Record, cstring] =
let lowerCaseAddress = toLowerAscii(address)
if lowerCaseAddress.startsWith("enr:"):
var enrRec: enr.Record
if enrRec.fromURI(address):
return ok enrRec
return err "Invalid ENR bootstrap record"
elif lowerCaseAddress.startsWith("enode:"):
return err "ENode bootstrap addresses are not supported"
else:
return err "Ignoring unrecognized bootstrap address type"
iterator strippedLines(filename: string): string {.raises: [ref IOError].} =
for line in lines(filename):
let stripped = strip(line)
if stripped.startsWith('#'): # Comments
continue
if stripped.len > 0:
yield stripped
proc addBootstrapNode*(bootstrapAddr: string,
bootstrapEnrs: var seq[enr.Record]) =
# Ignore empty lines or lines starting with #
if bootstrapAddr.len == 0 or bootstrapAddr[0] == '#':
return
# Ignore comments in
# https://github.com/eth-clients/eth2-networks/blob/063f826a03676c33c95a66306916f18b690d35eb/shared/mainnet/bootstrap_nodes.txt
let enrRes = parseBootstrapAddress(bootstrapAddr.split(" # ")[0])
if enrRes.isOk:
bootstrapEnrs.add enrRes.value
else:
warn "Ignoring invalid bootstrap address",
bootstrapAddr, reason = enrRes.error
proc loadBootstrapFile*(bootstrapFile: string,
bootstrapEnrs: var seq[enr.Record]) =
if bootstrapFile.len == 0: return
let ext = splitFile(bootstrapFile).ext
if cmpIgnoreCase(ext, ".txt") == 0 or cmpIgnoreCase(ext, ".enr") == 0 :
try:
for ln in strippedLines(bootstrapFile):
addBootstrapNode(ln, bootstrapEnrs)
except IOError as e:
error "Could not read bootstrap file", msg = e.msg
quit 1
else:
error "Unknown bootstrap file format", ext
quit 1
proc new*(T: type Eth2DiscoveryProtocol,
config: BeaconNodeConf | LightClientConf,
enrIp: Option[IpAddress], enrTcpPort, enrUdpPort: Option[Port],
pk: PrivateKey,
enrFields: openArray[(string, seq[byte])], rng: ref HmacDrbgContext):
T =
# TODO
# Implement more configuration options:
# * for setting up a specific key
# * for using a persistent database
var bootstrapEnrs: seq[enr.Record]
for node in config.bootstrapNodes:
addBootstrapNode(node, bootstrapEnrs)
loadBootstrapFile(string config.bootstrapNodesFile, bootstrapEnrs)
when config is BeaconNodeConf:
let persistentBootstrapFile = config.dataDir / "bootstrap_nodes.txt"
if fileExists(persistentBootstrapFile):
loadBootstrapFile(persistentBootstrapFile, bootstrapEnrs)
let listenAddress =
if config.listenAddress.isSome():
Opt.some(config.listenAddress.get())
else:
Opt.none(IpAddress)
newProtocol(pk, enrIp, enrTcpPort, enrUdpPort, enrFields, bootstrapEnrs,
bindPort = config.udpPort, bindIp = listenAddress,
enrAutoUpdate = config.enrAutoUpdate, rng = rng)
func isCompatibleForkId*(discoveryForkId: ENRForkID, peerForkId: ENRForkID): bool =
if discoveryForkId.fork_digest == peerForkId.fork_digest:
if discoveryForkId.next_fork_version < peerForkId.next_fork_version:
# Peer knows about a fork and we don't
true
elif discoveryForkId.next_fork_version == peerForkId.next_fork_version:
# We should have the same next_fork_epoch
discoveryForkId.next_fork_epoch == peerForkId.next_fork_epoch
else:
# Our next fork version is bigger than the peer's one
false
else:
# Wrong fork digest
false
proc queryRandom*(
d: Eth2DiscoveryProtocol,
forkId: ENRForkID,
wantedAttnets: AttnetBits,
wantedSyncnets: SyncnetBits,
minScore: int): Future[seq[Node]] {.async.} =
## Perform a discovery query for a random target
## (forkId) and matching at least one of the attestation subnets.
let nodes = await d.queryRandom()
var filtered: seq[(int, Node)]
for n in nodes:
var score: int = 0
let
eth2FieldBytes = n.record.get(enrForkIdField, seq[byte]).valueOr:
continue
peerForkId =
try:
SSZ.decode(eth2FieldBytes, ENRForkID)
except SszError as e:
debug "Could not decode the eth2 field of peer",
peer = n.record.toURI(), exception = e.name, msg = e.msg
continue
if not forkId.isCompatibleForkId(peerForkId):
continue
let attnetsBytes = n.record.get(enrAttestationSubnetsField, seq[byte])
if attnetsBytes.isOk():
let attnetsNode =
try:
SSZ.decode(attnetsBytes.get(), AttnetBits)
except SszError as e:
debug "Could not decode the attnets ERN bitfield of peer",
peer = n.record.toURI(), exception = e.name, msg = e.msg
continue
for i in 0..<ATTESTATION_SUBNET_COUNT:
if wantedAttnets[i] and attnetsNode[i]:
score += 1
let syncnetsBytes = n.record.get(enrSyncSubnetsField, seq[byte])
if syncnetsBytes.isOk():
let syncnetsNode =
try:
SSZ.decode(syncnetsBytes.get(), SyncnetBits)
except SszError as e:
debug "Could not decode the syncnets ENR bitfield of peer",
peer = n.record.toURI(), exception = e.name, msg = e.msg
continue
for i in SyncSubcommitteeIndex:
if wantedSyncnets[i] and syncnetsNode[i]:
score += 10 # connecting to the right syncnet is urgent
if score >= minScore:
filtered.add((score, n))
d.rng[].shuffle(filtered)
return filtered.sortedByIt(-it[0]).mapIt(it[1])