nimbus-eth2/beacon_chain/eth2_network.nim

1321 lines
46 KiB
Nim

import
# Std lib
std/[typetraits, strutils, os, algorithm, math, sets],
std/options as stdOptions,
# Status libs
stew/[varints, base58, base64, endians2, results, byteutils], bearssl,
stew/shims/net as stewNet,
stew/shims/[macros, tables],
faststreams/[inputs, outputs, buffers], snappy, snappy/framing,
json_serialization, json_serialization/std/[net, options],
chronos, chronicles, metrics,
# TODO: create simpler to use libp2p modules that use re-exports
libp2p/[switch, standard_setup, peerinfo,
multiaddress, multicodec, crypto/crypto, crypto/secp,
protocols/identify, protocols/protocol],
libp2p/protocols/secure/[secure, secio],
libp2p/protocols/pubsub/[pubsub, floodsub, gossipsub, rpc/message, rpc/messages],
libp2p/transports/tcptransport,
libp2p/stream/connection,
eth/[keys, async_utils], eth/p2p/p2p_protocol_dsl,
eth/net/nat, eth/p2p/discoveryv5/[enr, node],
# Beacon node modules
version, conf, eth2_discovery, libp2p_json_serialization, conf,
ssz/ssz_serialization,
peer_pool, spec/[datatypes, network], ./time
when chronicles.enabledLogLevel == LogLevel.TRACE:
import std/sequtils
export
version, multiaddress, peer_pool, peerinfo, p2pProtocol, connection,
libp2p_json_serialization, ssz_serialization, results
logScope:
topics = "networking"
type
KeyPair* = crypto.KeyPair
PublicKey* = crypto.PublicKey
PrivateKey* = crypto.PrivateKey
Bytes = seq[byte]
ErrorMsg = List[byte, 256]
# TODO: This is here only to eradicate a compiler
# warning about unused import (rpc/messages).
GossipMsg = messages.Message
SeenItem* = object
peerId*: PeerID
stamp*: chronos.Moment
# TODO Is this really needed?
Eth2Node* = ref object of RootObj
switch*: Switch
pubsub*: PubSub
discovery*: Eth2DiscoveryProtocol
discoveryEnabled*: bool
wantedPeers*: int
peerPool*: PeerPool[Peer, PeerID]
protocolStates*: seq[RootRef]
libp2pTransportLoops*: seq[Future[void]]
metadata*: Eth2Metadata
connectTimeout*: chronos.Duration
seenThreshold*: chronos.Duration
connQueue: AsyncQueue[PeerAddr]
seenTable: Table[PeerID, SeenItem]
connWorkers: seq[Future[void]]
connTable: HashSet[PeerID]
forkId: ENRForkID
rng*: ref BrHmacDrbgContext
peers: Table[PeerID, Peer]
EthereumNode = Eth2Node # needed for the definitions in p2p_backends_helpers
Eth2MetaData* = object
seq_number*: uint64
attnets*: BitArray[ATTESTATION_SUBNET_COUNT]
ENRForkID* = object
fork_digest*: ForkDigest
next_fork_version*: Version
next_fork_epoch*: Epoch
AverageThroughput* = object
count*: uint64
average*: float
Peer* = ref object
network*: Eth2Node
info*: PeerInfo
discoveryId*: Eth2DiscoveryId
connectionState*: ConnectionState
protocolStates*: seq[RootRef]
maxInactivityAllowed*: Duration
netThroughput: AverageThroughput
score*: int
connections*: int
disconnectedFut: Future[void]
PeerAddr* = object
peerId*: PeerID
addrs*: seq[MultiAddress]
ConnectionState* = enum
None,
Connecting,
Connected,
Disconnecting,
Disconnected
UntypedResponse = ref object
peer*: Peer
stream*: Connection
writtenChunks*: int
SingleChunkResponse*[MsgType] = distinct UntypedResponse
## Protocol requests using this type will produce request-making
## client-side procs that return `NetRes[MsgType]`
MultipleChunksResponse*[MsgType] = distinct UntypedResponse
## Protocol requests using this type will produce request-making
## client-side procs that return `NetRes[seq[MsgType]]`.
## In the future, such procs will return an `InputStream[NetRes[MsgType]]`.
MessageInfo* = object
name*: string
# Private fields:
libp2pCodecName: string
protocolMounter*: MounterProc
ProtocolInfoObj* = object
name*: string
messages*: seq[MessageInfo]
index*: int # the position of the protocol in the
# ordered list of supported protocols
# Private fields:
peerStateInitializer*: PeerStateInitializer
networkStateInitializer*: NetworkStateInitializer
onPeerConnected*: OnPeerConnectedHandler
onPeerDisconnected*: OnPeerDisconnectedHandler
ProtocolInfo* = ptr ProtocolInfoObj
ResponseCode* = enum
Success
InvalidRequest
ServerError
PeerStateInitializer* = proc(peer: Peer): RootRef {.gcsafe.}
NetworkStateInitializer* = proc(network: EthereumNode): RootRef {.gcsafe.}
OnPeerConnectedHandler* = proc(peer: Peer, incoming: bool): Future[void] {.gcsafe.}
OnPeerDisconnectedHandler* = proc(peer: Peer): Future[void] {.gcsafe.}
ThunkProc* = LPProtoHandler
MounterProc* = proc(network: Eth2Node) {.gcsafe.}
MessageContentPrinter* = proc(msg: pointer): string {.gcsafe.}
DisconnectionReason* = enum
# might see other values on the wire!
ClientShutDown = 1
IrrelevantNetwork = 2
FaultOrError = 3
PeerDisconnected* = object of CatchableError
reason*: DisconnectionReason
TransmissionError* = object of CatchableError
Eth2NetworkingErrorKind* = enum
BrokenConnection
ReceivedErrorResponse
UnexpectedEOF
PotentiallyExpectedEOF
InvalidResponseCode
InvalidSnappyBytes
InvalidSszBytes
StreamOpenTimeout
ReadResponseTimeout
ZeroSizePrefix
SizePrefixOverflow
Eth2NetworkingError = object
case kind*: Eth2NetworkingErrorKind
of ReceivedErrorResponse:
responseCode: ResponseCode
errorMsg: ErrorMsg
else:
discard
NetRes*[T] = Result[T, Eth2NetworkingError]
## This is type returned from all network requests
const
clientId* = "Nimbus beacon node v" & fullVersionStr
networkKeyFilename = "privkey.protobuf"
nodeMetadataFilename = "node-metadata.json"
TCP = net.Protocol.IPPROTO_TCP
HandshakeTimeout = FaultOrError
NewPeerScore* = 200
## Score which will be assigned to new connected Peer
PeerScoreLowLimit* = 0
## Score after which peer will be kicked
PeerScoreHighLimit* = 1000
## Max value of peer's score
ConcurrentConnections* = 10
## Maximum number of active concurrent connection requests.
SeenTableTimeTimeout* =
when not defined(local_testnet): 5.minutes else: 10.seconds
## Seen period of time for timeout connections
SeenTableTimeDeadPeer* =
when not defined(local_testnet): 5.minutes else: 10.seconds
## Period of time for dead peers.
SeenTableTimeIrrelevantNetwork* = 24.hours
## Period of time for `IrrelevantNetwork` error reason.
SeenTableTimeClientShutDown* = 10.minutes
## Period of time for `ClientShutDown` error reason.
SeemTableTimeFaultOrError* = 10.minutes
## Period of time for `FaultOnError` error reason.
var successfullyDialledAPeer = false # used to show a warning
template neterr(kindParam: Eth2NetworkingErrorKind): auto =
err(type(result), Eth2NetworkingError(kind: kindParam))
# Metrics for tracking attestation and beacon block loss
declareCounter nbc_gossip_messages_sent,
"Number of gossip messages sent by this peer"
declareCounter nbc_gossip_messages_received,
"Number of gossip messages received by this peer"
declarePublicCounter nbc_successful_dials,
"Number of successfully dialed peers"
declarePublicCounter nbc_failed_dials,
"Number of dialing attempts that failed"
declarePublicCounter nbc_timeout_dials,
"Number of dialing attempts that exceeded timeout"
declarePublicGauge nbc_peers,
"Number of active libp2p peers"
const
snappy_implementation {.strdefine.} = "libp2p"
const useNativeSnappy = when snappy_implementation == "native": true
elif snappy_implementation == "libp2p": false
else: {.fatal: "Please set snappy_implementation to either 'libp2p' or 'native'".}
const
libp2p_pki_schemes {.strdefine.} = ""
when libp2p_pki_schemes != "secp256k1":
{.fatal: "Incorrect building process, please use -d:\"libp2p_pki_schemes=secp256k1\"".}
template libp2pProtocol*(name: string, version: int) {.pragma.}
func shortLog*(peer: Peer): string = shortLog(peer.info.peerId)
chronicles.formatIt(Peer): shortLog(it)
template remote*(peer: Peer): untyped =
peer.info.peerId
proc openStream(node: Eth2Node,
peer: Peer,
protocolId: string): Future[Connection] {.async.} =
let
protocolId = protocolId & "ssz_snappy"
conn = await dial(
node.switch, peer.info.peerId, peer.info.addrs, protocolId)
# libp2p may replace peerinfo ref sometimes, so make sure we have a recent
# one
if conn.peerInfo != nil:
peer.info = conn.peerInfo
return conn
proc init*(T: type Peer, network: Eth2Node, info: PeerInfo): Peer {.gcsafe.}
proc getPeer*(node: Eth2Node, peerId: PeerID): Peer =
node.peers.withValue(peerId, peer) do:
return peer[]
do:
let peer = Peer.init(node, PeerInfo.init(peerId))
return node.peers.mGetOrPut(peerId, peer)
proc peerFromStream(network: Eth2Node, conn: Connection): Peer =
# TODO: Can this be `nil`?
return network.getPeer(conn.peerInfo.peerId)
proc getKey*(peer: Peer): PeerID {.inline.} =
result = peer.info.peerId
proc getFuture*(peer: Peer): Future[void] {.inline.} =
if peer.disconnectedFut.isNil:
peer.disconnectedFut = newFuture[void]()
result = peer.disconnectedFut
proc getScore*(a: Peer): int =
## Returns current score value for peer ``peer``.
result = a.score
proc updateScore*(peer: Peer, score: int) {.inline.} =
## Update peer's ``peer`` score with value ``score``.
peer.score = peer.score + score
if peer.score > PeerScoreHighLimit:
peer.score = PeerScoreHighLimit
proc calcThroughput(dur: Duration, value: uint64): float {.inline.} =
let secs = float(chronos.seconds(1).nanoseconds)
if isZero(dur):
0.0
else:
float(value) * (secs / float(dur.nanoseconds))
proc updateNetThroughput*(peer: Peer, dur: Duration,
bytesCount: uint64) {.inline.} =
## Update peer's ``peer`` network throughput.
let bytesPerSecond = calcThroughput(dur, bytesCount)
let a = peer.netThroughput.average
let n = peer.netThroughput.count
peer.netThroughput.average = a + (bytesPerSecond - a) / float(n + 1)
inc(peer.netThroughput.count)
proc netBps*(peer: Peer): float {.inline.} =
## Returns current network throughput average value in Bps for peer ``peer``.
round((peer.netThroughput.average * 10_000) / 10_000)
proc netKbps*(peer: Peer): float {.inline.} =
## Returns current network throughput average value in Kbps for peer ``peer``.
round(((peer.netThroughput.average / 1024) * 10_000) / 10_000)
proc netMbps*(peer: Peer): float {.inline.} =
## Returns current network throughput average value in Mbps for peer ``peer``.
round(((peer.netThroughput.average / (1024 * 1024)) * 10_000) / 10_000)
proc `<`*(a, b: Peer): bool =
## Comparison function, which first checks peer's scores, and if the peers'
## score is equal it compares peers' network throughput.
if a.score < b.score:
true
elif a.score == b.score:
(a.netThroughput.average < b.netThroughput.average)
else:
false
proc isSeen*(network: ETh2Node, peerId: PeerID): bool =
let currentTime = now(chronos.Moment)
if peerId notin network.seenTable:
return false
let item = network.seenTable[peerId]
if currentTime >= item.stamp:
# Peer is in SeenTable, but the time period has expired.
network.seenTable.del(peerId)
return false
return true
proc addSeen*(network: ETh2Node, peerId: PeerID,
period: chronos.Duration) =
let item = SeenItem(peerId: peerId, stamp: now(chronos.Moment) + period)
network.seenTable[peerId] = item
proc disconnect*(peer: Peer, reason: DisconnectionReason,
notifyOtherPeer = false) {.async.} =
# TODO: How should we notify the other peer?
if peer.connectionState notin {Disconnecting, Disconnected}:
peer.connectionState = Disconnecting
await peer.network.switch.disconnect(peer.info.peerId)
peer.connectionState = Disconnected
peer.network.peerPool.release(peer)
let seenTime = case reason
of ClientShutDown:
SeenTableTimeClientShutDown
of IrrelevantNetwork:
SeenTableTimeIrrelevantNetwork
of FaultOrError:
SeemTableTimeFaultOrError
peer.network.addSeen(peer.info.peerId, seenTime)
include eth/p2p/p2p_backends_helpers
include eth/p2p/p2p_tracing
proc getRequestProtoName(fn: NimNode): NimNode =
# `getCustomPragmaVal` doesn't work yet on regular nnkProcDef nodes
# (TODO: file as an issue)
let pragmas = fn.pragma
if pragmas.kind == nnkPragma and pragmas.len > 0:
for pragma in pragmas:
if pragma.len > 0 and $pragma[0] == "libp2pProtocol":
let protoName = $(pragma[1])
let protoVer = $(pragma[2].intVal)
return newLit("/eth2/beacon_chain/req/" & protoName & "/" & protoVer & "/")
return newLit("")
template raisePeerDisconnected(msg: string, r: DisconnectionReason) =
var e = newException(PeerDisconnected, msg)
e.reason = r
raise e
proc disconnectAndRaise(peer: Peer,
reason: DisconnectionReason,
msg: string) {.async.} =
let r = reason
await peer.disconnect(r)
raisePeerDisconnected(msg, r)
proc writeChunk*(conn: Connection,
responseCode: Option[ResponseCode],
payload: Bytes) {.async.} =
var output = memoryOutput()
if responseCode.isSome:
output.write byte(responseCode.get)
output.write varintBytes(payload.lenu64)
output.write(framingFormatCompress payload)
await conn.write(output.getOutput)
template errorMsgLit(x: static string): ErrorMsg =
const val = ErrorMsg toBytes(x)
val
proc formatErrorMsg(msg: ErrorMSg): string =
let candidate = string.fromBytes(asSeq(msg))
for c in candidate:
# TODO UTF-8 - but let's start with ASCII
if ord(c) < 32 or ord(c) > 127:
return byteutils.toHex(asSeq(msg))
return candidate
proc sendErrorResponse(peer: Peer,
conn: Connection,
responseCode: ResponseCode,
errMsg: ErrorMsg) {.async.} =
debug "Error processing request",
peer, responseCode, errMsg = formatErrorMsg(errMsg)
await conn.writeChunk(some responseCode, SSZ.encode(errMsg))
proc sendNotificationMsg(peer: Peer, protocolId: string, requestBytes: Bytes) {.async} =
var
deadline = sleepAsync RESP_TIMEOUT
streamFut = peer.network.openStream(peer, protocolId)
await streamFut or deadline
if not streamFut.finished:
streamFut.cancel()
raise newException(TransmissionError, "Failed to open LibP2P stream")
let stream = streamFut.read
try:
await stream.writeChunk(none ResponseCode, requestBytes)
finally:
await stream.close()
proc sendResponseChunkBytes(response: UntypedResponse, payload: Bytes) {.async.} =
inc response.writtenChunks
await response.stream.writeChunk(some Success, payload)
proc sendResponseChunkObj(response: UntypedResponse, val: auto) {.async.} =
inc response.writtenChunks
await response.stream.writeChunk(some Success, SSZ.encode(val))
template sendUserHandlerResultAsChunkImpl*(stream: Connection,
handlerResultFut: Future): untyped =
let handlerRes = await handlerResultFut
writeChunk(stream, some Success, SSZ.encode(handlerRes))
template sendUserHandlerResultAsChunkImpl*(stream: Connection,
handlerResult: auto): untyped =
writeChunk(stream, some Success, SSZ.encode(handlerResult))
when useNativeSnappy:
include faststreams_backend
else:
include libp2p_streams_backend
proc makeEth2Request(peer: Peer, protocolId: string, requestBytes: Bytes,
ResponseMsg: type,
timeout: Duration): Future[NetRes[ResponseMsg]]
{.async.} =
var deadline = sleepAsync timeout
let stream = awaitWithTimeout(peer.network.openStream(peer, protocolId),
deadline): return neterr StreamOpenTimeout
try:
# Send the request
await stream.writeChunk(none ResponseCode, requestBytes)
# Half-close the stream to mark the end of the request - if this is not
# done, the other peer might never send us the response.
await stream.close()
# Read the response
return
await readResponse(when useNativeSnappy: libp2pInput(stream) else: stream,
peer, ResponseMsg, timeout)
finally:
await stream.close()
proc init*[MsgType](T: type MultipleChunksResponse[MsgType],
peer: Peer, conn: Connection): T =
T(UntypedResponse(peer: peer, stream: conn))
proc init*[MsgType](T: type SingleChunkResponse[MsgType],
peer: Peer, conn: Connection): T =
T(UntypedResponse(peer: peer, stream: conn))
template write*[M](r: MultipleChunksResponse[M], val: auto): untyped =
sendResponseChunkObj(UntypedResponse(r), val)
template send*[M](r: SingleChunkResponse[M], val: auto): untyped =
doAssert UntypedResponse(r).writtenChunks == 0
sendResponseChunkObj(UntypedResponse(r), val)
proc performProtocolHandshakes*(peer: Peer, incoming: bool) {.async.} =
# Loop down serially because it's easier to reason about the connection state
# when there are fewer async races, specially during setup
for protocol in allProtocols:
if protocol.onPeerConnected != nil:
await protocol.onPeerConnected(peer, incoming)
proc initProtocol(name: string,
peerInit: PeerStateInitializer,
networkInit: NetworkStateInitializer): ProtocolInfoObj =
result.name = name
result.messages = @[]
result.peerStateInitializer = peerInit
result.networkStateInitializer = networkInit
proc registerProtocol(protocol: ProtocolInfo) =
# TODO: This can be done at compile-time in the future
let pos = lowerBound(gProtocols, protocol)
gProtocols.insert(protocol, pos)
for i in 0 ..< gProtocols.len:
gProtocols[i].index = i
proc setEventHandlers(p: ProtocolInfo,
onPeerConnected: OnPeerConnectedHandler,
onPeerDisconnected: OnPeerDisconnectedHandler) =
p.onPeerConnected = onPeerConnected
p.onPeerDisconnected = onPeerDisconnected
proc implementSendProcBody(sendProc: SendProc) =
let
msg = sendProc.msg
UntypedResponse = bindSym "UntypedResponse"
proc sendCallGenerator(peer, bytes: NimNode): NimNode =
if msg.kind != msgResponse:
let msgProto = getRequestProtoName(msg.procDef)
case msg.kind
of msgRequest:
let ResponseRecord = msg.response.recName
quote:
makeEth2Request(`peer`, `msgProto`, `bytes`,
`ResponseRecord`, `timeoutVar`)
else:
quote: sendNotificationMsg(`peer`, `msgProto`, `bytes`)
else:
quote: sendResponseChunkBytes(`UntypedResponse`(`peer`), `bytes`)
sendProc.useStandardBody(nil, nil, sendCallGenerator)
proc handleIncomingStream(network: Eth2Node,
conn: Connection,
MsgType: type) {.async.} =
mixin callUserHandler, RecType
type MsgRec = RecType(MsgType)
const msgName {.used.} = typetraits.name(MsgType)
## Uncomment this to enable tracing on all incoming requests
## You can include `msgNameLit` in the condition to select
## more specific requests:
# when chronicles.runtimeFilteringEnabled:
# setLogLevel(LogLevel.TRACE)
# defer: setLogLevel(LogLevel.DEBUG)
# trace "incoming " & `msgNameLit` & " conn"
try:
let peer = peerFromStream(network, conn)
# TODO peer connection setup is broken, update info in some better place
# whenever race is fix:
# https://github.com/status-im/nim-beacon-chain/issues/1157
peer.info = conn.peerInfo
template returnInvalidRequest(msg: ErrorMsg) =
await sendErrorResponse(peer, conn, InvalidRequest, msg)
return
template returnInvalidRequest(msg: string) =
returnInvalidRequest(ErrorMsg msg.toBytes)
let s = when useNativeSnappy:
let fs = libp2pInput(conn)
if fs.timeoutToNextByte(TTFB_TIMEOUT):
returnInvalidRequest(errorMsgLit "Request first byte not sent in time")
fs
else:
# TODO The TTFB timeout is not implemented in LibP2P streams back-end
conn
let deadline = sleepAsync RESP_TIMEOUT
let msg = if sizeof(MsgRec) > 0:
try:
awaitWithTimeout(readChunkPayload(s, peer, MsgRec), deadline):
returnInvalidRequest(errorMsgLit "Request full data not sent in time")
except SerializationError as err:
returnInvalidRequest err.formatMsg("msg")
except SnappyError as err:
returnInvalidRequest err.msg
else:
NetRes[MsgRec].ok default(MsgRec)
if msg.isErr:
let (responseCode, errMsg) = case msg.error.kind
of UnexpectedEOF, PotentiallyExpectedEOF:
(InvalidRequest, errorMsgLit "Incomplete request")
of InvalidSnappyBytes:
(InvalidRequest, errorMsgLit "Failed to decompress snappy payload")
of InvalidSszBytes:
(InvalidRequest, errorMsgLit "Failed to decode SSZ payload")
of ZeroSizePrefix:
(InvalidRequest, errorMsgLit "The request chunk cannot have a size of zero")
of SizePrefixOverflow:
(InvalidRequest, errorMsgLit "The chunk size exceed the maximum allowed")
of InvalidResponseCode, ReceivedErrorResponse,
StreamOpenTimeout, ReadResponseTimeout:
# These shouldn't be possible in a request, because
# there are no response codes being read, no stream
# openings and no reading of responses:
(ServerError, errorMsgLit "Internal server error")
of BrokenConnection:
return
await sendErrorResponse(peer, conn, responseCode, errMsg)
return
try:
logReceivedMsg(peer, MsgType(msg.get))
await callUserHandler(MsgType, peer, conn, msg.get)
except CatchableError as err:
await sendErrorResponse(peer, conn, ServerError,
ErrorMsg err.msg.toBytes)
except CatchableError as err:
debug "Error processing an incoming request", err = err.msg, msgName
finally:
await conn.close()
proc handleOutgoingPeer(peer: Peer): Future[bool] {.async.} =
let network = peer.network
proc onPeerClosed(udata: pointer) =
debug "Peer (outgoing) lost", peer
nbc_peers.set int64(len(network.peerPool))
let res = await network.peerPool.addOutgoingPeer(peer)
if res:
peer.updateScore(NewPeerScore)
debug "Peer (outgoing) has been added to PeerPool", peer
peer.getFuture().addCallback(onPeerClosed)
result = true
nbc_peers.set int64(len(network.peerPool))
proc handleIncomingPeer(peer: Peer): Future[bool] {.async.} =
let network = peer.network
proc onPeerClosed(udata: pointer) =
debug "Peer (incoming) lost", peer
nbc_peers.set int64(len(network.peerPool))
let res = await network.peerPool.addIncomingPeer(peer)
if res:
peer.updateScore(NewPeerScore)
debug "Peer (incoming) has been added to PeerPool", peer
peer.getFuture().addCallback(onPeerClosed)
result = true
nbc_peers.set int64(len(network.peerPool))
proc toPeerAddr*(r: enr.TypedRecord):
Result[PeerAddr, cstring] {.raises: [Defect].} =
if not r.secp256k1.isSome:
return err("enr: no secp256k1 key in record")
let
pubKey = ? keys.PublicKey.fromRaw(r.secp256k1.get)
peerId = ? PeerID.init(crypto.PublicKey(
scheme: Secp256k1, skkey: secp.SkPublicKey(pubKey)))
var addrs = newSeq[MultiAddress]()
if r.ip.isSome and r.tcp.isSome:
let ip = ipv4(r.ip.get)
addrs.add MultiAddress.init(ip, tcpProtocol, Port r.tcp.get)
if r.ip6.isSome:
let ip = ipv6(r.ip6.get)
if r.tcp6.isSome:
addrs.add MultiAddress.init(ip, tcpProtocol, Port r.tcp6.get)
elif r.tcp.isSome:
addrs.add MultiAddress.init(ip, tcpProtocol, Port r.tcp.get)
else:
discard
if addrs.len == 0:
return err("enr: no addresses in record")
ok(PeerAddr(peerId: peerId, addrs: addrs))
proc dialPeer*(node: Eth2Node, peerAddr: PeerAddr) {.async.} =
logScope: peer = peerAddr.peerId
debug "Connecting to discovered peer"
# TODO connect is called here, but there's no guarantee that the connection
# we get when using dialPeer later on is the one we just connected
await node.switch.connect(peerAddr.peerId, peerAddr.addrs)
#let msDial = newMultistream()
#let conn = node.switch.connections.getOrDefault(peerInfo.id)
#let ls = await msDial.list(conn)
#debug "Supported protocols", ls
inc nbc_successful_dials
successfullyDialledAPeer = true
debug "Network handshakes completed"
proc connectWorker(network: Eth2Node) {.async.} =
debug "Connection worker started"
while true:
let
remotePeerAddr = await network.connQueue.popFirst()
peerPoolHasRemotePeer = network.peerPool.hasPeer(remotePeerAddr.peerId)
seenTableHasRemotePeer = network.isSeen(remotePeerAddr.peerId)
remotePeerAlreadyConnected = remotePeerAddr.peerId in network.connTable
if not(peerPoolHasRemotePeer) and not(seenTableHasRemotePeer) and not(remotePeerAlreadyConnected):
network.connTable.incl(remotePeerAddr.peerId)
try:
# We trying to connect to peers which are not in PeerPool, SeenTable and
# ConnTable.
var fut = network.dialPeer(remotePeerAddr)
# We discarding here just because we going to check future state, to avoid
# condition where connection happens and timeout reached.
discard await withTimeout(fut, network.connectTimeout)
# We handling only timeout and errors, because successfull connections
# will be stored in PeerPool.
if fut.finished():
if fut.failed() and not(fut.cancelled()):
debug "Unable to establish connection with peer", peer = remotePeerAddr.peerId,
errMsg = fut.readError().msg
inc nbc_failed_dials
network.addSeen(remotePeerAddr.peerId, SeenTableTimeDeadPeer)
continue
debug "Connection to remote peer timed out", peer = remotePeerAddr.peerId
inc nbc_timeout_dials
network.addSeen(remotePeerAddr.peerId, SeenTableTimeTimeout)
finally:
network.connTable.excl(remotePeerAddr.peerId)
else:
trace "Peer is already connected, connecting or already seen",
peer = remotePeerAddr.peerId, peer_pool_has_peer = $peerPoolHasRemotePeer, seen_table_has_peer = $seenTableHasRemotePeer,
connecting_peer = $remotePeerAlreadyConnected, seen_table_size = len(network.seenTable)
# Prevent (a purely theoretical) high CPU usage when losing connectivity.
await sleepAsync(1.seconds)
proc runDiscoveryLoop*(node: Eth2Node) {.async.} =
debug "Starting discovery loop"
let enrField = ("eth2", SSZ.encode(node.forkId))
while true:
let currentPeerCount = node.peerPool.len
if currentPeerCount < node.wantedPeers:
try:
let discoveredPeers =
node.discovery.randomNodes(node.wantedPeers - currentPeerCount,
enrField)
for peer in discoveredPeers:
try:
let peerRecord = peer.record.toTypedRecord
if peerRecord.isOk:
let peerAddr = peerRecord.value.toPeerAddr
if peerAddr.isOk:
if not node.switch.isConnected(peerAddr.get().peerId):
await node.connQueue.addLast(peerAddr.get())
else:
discard # peerInfo.close()
except CatchableError as err:
debug "Failed to connect to peer", peer = $peer, err = err.msg
except CatchableError as err:
debug "Failure in discovery", err = err.msg
await sleepAsync seconds(1)
proc getPersistentNetMetadata*(conf: BeaconNodeConf): Eth2Metadata =
let metadataPath = conf.dataDir / nodeMetadataFilename
if not fileExists(metadataPath):
result = Eth2Metadata()
for i in 0 ..< ATTESTATION_SUBNET_COUNT:
# TODO: For now, we indicate that we participate in all subnets
result.attnets[i] = true
Json.saveFile(metadataPath, result)
else:
result = Json.loadFile(metadataPath, Eth2Metadata)
proc onConnEvent(node: Eth2Node, peerId: PeerID, event: ConnEvent) {.async.} =
let peer = node.getPeer(peerId)
case event.kind
of ConnEventKind.Connected:
inc peer.connections
debug "Peer upgraded", peer = $peerId, connections = peer.connections
if peer.connections == 1:
# Libp2p may connect multiple times to the same peer - using different
# transports for both incoming and outgoing. For now, we'll count our
# "fist" encounter with the peer as the true connection, leaving the
# other connections be - libp2p limits the number of concurrent
# connections to the same peer, and only one of these connections will be
# active. Nonetheless, this quirk will cause a number of odd behaviours:
# * For peer limits, we might miscount the incoming vs outgoing quota
# * Protocol handshakes are wonky: we'll not necessarily use the newly
# connected transport - instead we'll just pick a random one!
node.pubsub.subscribePeer(peerId)
await performProtocolHandshakes(peer, event.incoming)
# While performing the handshake, the peer might have been disconnected -
# there's still a slim chance of a race condition here if a reconnect
# happens quickly
if peer.connections == 1:
# TODO when the pool is full, adding it will block - this means peers
# will be left in limbo until some other peer makes room for it
let added = if event.incoming:
await handleIncomingPeer(peer)
else:
await handleOutgoingPeer(peer)
if not added:
# We must have hit a limit!
await peer.disconnect(FaultOrError)
of ConnEventKind.Disconnected:
dec peer.connections
debug "Peer disconnected", peer = $peerId, connections = peer.connections
if peer.connections == 0:
node.pubsub.unsubscribePeer(peerId)
let fut = peer.disconnectedFut
if fut != nil:
peer.disconnectedFut = nil
fut.complete()
proc init*(T: type Eth2Node, conf: BeaconNodeConf, enrForkId: ENRForkID,
switch: Switch, pubsub: PubSub, ip: Option[ValidIpAddress],
tcpPort, udpPort: Port, privKey: keys.PrivateKey, discovery: bool,
rng: ref BrHmacDrbgContext): T =
new result
result.switch = switch
result.pubsub = pubsub
result.wantedPeers = conf.maxPeers
result.peerPool = newPeerPool[Peer, PeerID](maxPeers = conf.maxPeers)
when not defined(local_testnet):
result.connectTimeout = 1.minutes
result.seenThreshold = 5.minutes
else:
result.connectTimeout = 10.seconds
result.seenThreshold = 10.seconds
result.seenTable = initTable[PeerID, SeenItem]()
result.connTable = initHashSet[PeerID]()
result.connQueue = newAsyncQueue[PeerAddr](ConcurrentConnections)
result.metadata = getPersistentNetMetadata(conf)
result.forkId = enrForkId
result.discovery = Eth2DiscoveryProtocol.new(
conf, ip, tcpPort, udpPort, privKey,
{"eth2": SSZ.encode(result.forkId), "attnets": SSZ.encode(result.metadata.attnets)},
rng)
result.discoveryEnabled = discovery
newSeq result.protocolStates, allProtocols.len
for proto in allProtocols:
if proto.networkStateInitializer != nil:
result.protocolStates[proto.index] = proto.networkStateInitializer(result)
for msg in proto.messages:
if msg.protocolMounter != nil:
msg.protocolMounter result
let node = result
proc peerHook(peerId: PeerID, event: ConnEvent): Future[void] {.gcsafe.} =
onConnEvent(node, peerId, event)
switch.addConnEventHandler(peerHook, ConnEventKind.Connected)
switch.addConnEventHandler(peerHook, ConnEventKind.Disconnected)
template publicKey*(node: Eth2Node): keys.PublicKey =
node.discovery.privKey.toPublicKey
proc startListening*(node: Eth2Node) {.async.} =
if node.discoveryEnabled:
node.discovery.open()
node.libp2pTransportLoops = await node.switch.start()
await node.pubsub.start()
proc start*(node: Eth2Node) {.async.} =
for i in 0 ..< ConcurrentConnections:
node.connWorkers.add connectWorker(node)
if node.discoveryEnabled:
node.discovery.start()
traceAsyncErrors node.runDiscoveryLoop()
else:
debug "Discovery disabled, trying bootstrap nodes",
nodes = node.discovery.bootstrapRecords.len
for enr in node.discovery.bootstrapRecords:
let tr = enr.toTypedRecord()
if tr.isOk():
let pa = tr.get().toPeerAddr()
if pa.isOk():
await node.connQueue.addLast(pa.get())
proc stop*(node: Eth2Node) {.async.} =
# Ignore errors in futures, since we're shutting down (but log them on the
# TRACE level, if a timeout is reached).
let
waitedFutures = @[
node.discovery.closeWait(),
node.switch.stop(),
]
timeout = 5.seconds
completed = await withTimeout(allFutures(waitedFutures), timeout)
if not completed:
trace "Eth2Node.stop(): timeout reached", timeout,
futureErrors = waitedFutures.filterIt(it.error != nil).mapIt(it.error.msg)
proc init*(T: type Peer, network: Eth2Node, info: PeerInfo): Peer =
new result
result.info = info
result.network = network
result.connectionState = Connected
result.maxInactivityAllowed = 15.minutes # TODO: Read this from the config
newSeq result.protocolStates, allProtocols.len
for i in 0 ..< allProtocols.len:
let proto = allProtocols[i]
if proto.peerStateInitializer != nil:
result.protocolStates[i] = proto.peerStateInitializer(result)
proc registerMsg(protocol: ProtocolInfo,
name: string,
mounter: MounterProc,
libp2pCodecName: string) =
protocol.messages.add MessageInfo(name: name,
protocolMounter: mounter,
libp2pCodecName: libp2pCodecName)
proc p2pProtocolBackendImpl*(p: P2PProtocol): Backend =
var
Format = ident "SSZ"
Bool = bindSym "bool"
Connection = bindSym "Connection"
Peer = bindSym "Peer"
Eth2Node = bindSym "Eth2Node"
registerMsg = bindSym "registerMsg"
initProtocol = bindSym "initProtocol"
msgVar = ident "msg"
networkVar = ident "network"
callUserHandler = ident "callUserHandler"
MSG = ident "MSG"
p.useRequestIds = false
p.useSingleRecordInlining = true
new result
result.PeerType = Peer
result.NetworkType = Eth2Node
result.registerProtocol = bindSym "registerProtocol"
result.setEventHandlers = bindSym "setEventHandlers"
result.SerializationFormat = Format
result.RequestResultsWrapper = ident "NetRes"
result.implementMsg = proc (msg: p2p_protocol_dsl.Message) =
if msg.kind == msgResponse:
return
let
protocol = msg.protocol
msgName = $msg.ident
msgNameLit = newLit msgName
MsgRecName = msg.recName
MsgStrongRecName = msg.strongRecName
codecNameLit = getRequestProtoName(msg.procDef)
protocolMounterName = ident(msgName & "Mounter")
##
## Implement the Thunk:
##
## The protocol handlers in nim-libp2p receive only a `Connection`
## parameter and there is no way to access the wider context (such
## as the current `Switch`). In our handlers, we may need to list all
## peers in the current network, so we must keep a reference to the
## network object in the closure environment of the installed handlers.
##
## For this reason, we define a `protocol mounter` proc that will
## initialize the network object by creating handlers bound to the
## specific network.
##
var userHandlerCall = newTree(nnkDiscardStmt)
if msg.userHandler != nil:
var OutputParamType = if msg.kind == msgRequest: msg.outputParamType
else: nil
if OutputParamType == nil:
userHandlerCall = msg.genUserHandlerCall(msgVar, [peerVar])
if msg.kind == msgRequest:
userHandlerCall = newCall(ident"sendUserHandlerResultAsChunkImpl",
streamVar,
userHandlerCall)
else:
if OutputParamType.kind == nnkVarTy:
OutputParamType = OutputParamType[0]
let isChunkStream = eqIdent(OutputParamType[0], "MultipleChunksResponse")
msg.response.recName = if isChunkStream:
newTree(nnkBracketExpr, ident"seq", OutputParamType[1])
else:
OutputParamType[1]
let responseVar = ident("response")
userHandlerCall = newStmtList(
newVarStmt(responseVar,
newCall(ident"init", OutputParamType,
peerVar, streamVar)),
msg.genUserHandlerCall(msgVar, [peerVar], outputParam = responseVar))
protocol.outRecvProcs.add quote do:
template `callUserHandler`(`MSG`: type `MsgStrongRecName`,
`peerVar`: `Peer`,
`streamVar`: `Connection`,
`msgVar`: `MsgRecName`): untyped =
`userHandlerCall`
proc `protocolMounterName`(`networkVar`: `Eth2Node`) =
proc snappyThunk(`streamVar`: `Connection`,
`protocolVar`: string): Future[void] {.gcsafe.} =
return handleIncomingStream(`networkVar`, `streamVar`,
`MsgStrongRecName`)
mount `networkVar`.switch,
LPProtocol(codec: `codecNameLit` & "ssz_snappy",
handler: snappyThunk)
##
## Implement Senders and Handshake
##
if msg.kind == msgHandshake:
macros.error "Handshake messages are not supported in LibP2P protocols"
else:
var sendProc = msg.createSendProc()
implementSendProcBody sendProc
protocol.outProcRegistrations.add(
newCall(registerMsg,
protocol.protocolInfoVar,
msgNameLit,
protocolMounterName,
codecNameLit))
result.implementProtocolInit = proc (p: P2PProtocol): NimNode =
return newCall(initProtocol, newLit(p.name), p.peerInit, p.netInit)
proc setupNat(conf: BeaconNodeConf): tuple[ip: Option[ValidIpAddress],
tcpPort: Port,
udpPort: Port] =
# defaults
result.tcpPort = conf.tcpPort
result.udpPort = conf.udpPort
var nat: NatStrategy
case conf.nat.toLowerAscii:
of "any":
nat = NatAny
of "none":
nat = NatNone
of "upnp":
nat = NatUpnp
of "pmp":
nat = NatPmp
else:
if conf.nat.startsWith("extip:"):
try:
# any required port redirection is assumed to be done by hand
result.ip = some(ValidIpAddress.init(conf.nat[6..^1]))
nat = NatNone
except ValueError:
error "nor a valid IP address", address = conf.nat[6..^1]
quit QuitFailure
else:
error "not a valid NAT mechanism", value = conf.nat
quit QuitFailure
if nat != NatNone:
let extIp = getExternalIP(nat)
if extIP.isSome:
result.ip = some(ValidIpAddress.init extIp.get)
# TODO redirectPorts in considered a gcsafety violation
# because it obtains the address of a non-gcsafe proc?
let extPorts = ({.gcsafe.}:
redirectPorts(tcpPort = result.tcpPort,
udpPort = result.udpPort,
description = clientId))
if extPorts.isSome:
(result.tcpPort, result.udpPort) = extPorts.get()
func asLibp2pKey*(key: keys.PublicKey): PublicKey =
PublicKey(scheme: Secp256k1, skkey: secp.SkPublicKey(key))
func asEthKey*(key: PrivateKey): keys.PrivateKey =
keys.PrivateKey(key.skkey)
proc initAddress*(T: type MultiAddress, str: string): T =
let address = MultiAddress.init(str)
if IPFS.match(address) and matchPartial(multiaddress.TCP, address):
result = address
else:
raise newException(MultiAddressError,
"Invalid bootstrap node multi-address")
template tcpEndPoint(address, port): auto =
MultiAddress.init(address, tcpProtocol, port)
proc getPersistentNetKeys*(
rng: var BrHmacDrbgContext, conf: BeaconNodeConf): KeyPair =
let
privKeyPath = conf.dataDir / networkKeyFilename
privKey =
if not fileExists(privKeyPath):
createDir conf.dataDir.string
let key = PrivateKey.random(Secp256k1, rng).tryGet()
writeFile(privKeyPath, key.getBytes().tryGet())
key
else:
let keyBytes = readFile(privKeyPath)
PrivateKey.init(keyBytes.toOpenArrayByte(0, keyBytes.high)).tryGet()
KeyPair(seckey: privKey, pubkey: privKey.getKey().tryGet())
func gossipId(data: openArray[byte]): string =
# https://github.com/ethereum/eth2.0-specs/blob/v0.12.2/specs/phase0/p2p-interface.md#topics-and-messages
base64.encode(Base64Url, sha256.digest(data).data)
func msgIdProvider(m: messages.Message): string =
gossipId(m.data)
proc createEth2Node*(
rng: ref BrHmacDrbgContext, conf: BeaconNodeConf,
enrForkId: ENRForkID): Eth2Node =
var
(extIp, extTcpPort, extUdpPort) = setupNat(conf)
hostAddress = tcpEndPoint(conf.libp2pAddress, conf.tcpPort)
announcedAddresses = if extIp.isNone(): @[]
else: @[tcpEndPoint(extIp.get(), extTcpPort)]
info "Initializing networking", hostAddress,
announcedAddresses
let keys = getPersistentNetKeys(rng[], conf)
# TODO nim-libp2p still doesn't have support for announcing addresses
# that are different from the host address (this is relevant when we
# are running behind a NAT).
var switch = newStandardSwitch(some keys.seckey, hostAddress,
transportFlags = {ServerFlags.ReuseAddr},
secureManagers = [
SecureProtocol.Noise, # Only noise in ETH2!
],
rng = rng)
let pubsub = GossipSub.init(
switch = switch,
msgIdProvider = msgIdProvider,
triggerSelf = true, sign = false,
verifySignature = false).PubSub
switch.mount(pubsub)
result = Eth2Node.init(conf, enrForkId, switch, pubsub,
extIp, extTcpPort, extUdpPort,
keys.seckey.asEthKey, discovery = conf.discv5Enabled,
rng = rng)
proc getPersistenBootstrapAddr*(rng: var BrHmacDrbgContext, conf: BeaconNodeConf,
ip: ValidIpAddress, port: Port): EnrResult[enr.Record] =
let pair = getPersistentNetKeys(rng, conf)
return enr.Record.init(1'u64, # sequence number
pair.seckey.asEthKey,
some(ip), port, port, @[])
proc announcedENR*(node: Eth2Node): enr.Record =
doAssert node.discovery != nil, "The Eth2Node must be initialized"
node.discovery.localNode.record
proc shortForm*(id: KeyPair): string =
$PeerID.init(id.pubkey)
let BOOTSTRAP_NODE_CHECK_INTERVAL = 30.seconds
proc checkIfConnectedToBootstrapNode(p: pointer) {.gcsafe.} =
# Keep showing warnings until we connect to at least one bootstrap node
# successfully, in order to allow detection of an invalid configuration.
let node = cast[Eth2Node](p)
if node.discovery.bootstrapRecords.len > 0 and not successfullyDialledAPeer:
warn "Failed to connect to any bootstrap node",
bootstrapEnrs = node.discovery.bootstrapRecords
addTimer(BOOTSTRAP_NODE_CHECK_INTERVAL, checkIfConnectedToBootstrapNode, p)
proc startLookingForPeers*(node: Eth2Node) {.async.} =
await node.start()
addTimer(BOOTSTRAP_NODE_CHECK_INTERVAL, checkIfConnectedToBootstrapNode, node[].addr)
func peersCount*(node: Eth2Node): int =
len(node.peerPool)
proc subscribe*[MsgType](node: Eth2Node,
topic: string,
msgHandler: proc(msg: MsgType) {.gcsafe.} ) {.async.} =
proc execMsgHandler(topic: string, data: seq[byte]) {.async.} =
inc nbc_gossip_messages_received
trace "Incoming pubsub message received",
len = data.len, topic, msgId = gossipId(data)
try:
let decompressed = snappy.decode(data, GOSSIP_MAX_SIZE)
if decompressed.len > 0:
msgHandler SSZ.decode(decompressed, MsgType)
else:
# TODO penalize peer?
debug "Failed to decompress gossip payload"
except CatchableError as err:
debug "Gossip msg handler error",
msg = err.msg, len = data.len, topic, msgId = gossipId(data)
await node.pubsub.subscribe(topic & "_snappy", execMsgHandler)
proc subscribe*(node: Eth2Node, topic: string) {.async.} =
proc dummyMsgHandler(topic: string, data: seq[byte]) {.async.} =
discard
await node.pubsub.subscribe(topic & "_snappy", dummyMsgHandler)
proc addValidator*[MsgType](node: Eth2Node,
topic: string,
msgValidator: proc(msg: MsgType): bool {.gcsafe.} ) =
# Validate messages as soon as subscribed
proc execValidator(
topic: string, message: GossipMsg): Future[bool] {.async.} =
trace "Validating incoming gossip message",
len = message.data.len, topic, msgId = gossipId(message.data)
try:
let decompressed = snappy.decode(message.data, GOSSIP_MAX_SIZE)
if decompressed.len > 0:
return msgValidator SSZ.decode(decompressed, MsgType)
else:
# TODO penalize peer?
debug "Failed to decompress gossip payload"
except CatchableError as err:
debug "Gossip validation error",
msg = err.msg, msgId = gossipId(message.data)
return false
node.pubsub.addValidator(topic & "_snappy", execValidator)
proc unsubscribe*(node: Eth2Node, topic: string): Future[void] =
node.pubsub.unsubscribeAll(topic)
proc traceMessage(fut: FutureBase, msgId: string) =
fut.addCallback do (arg: pointer):
if not(fut.failed):
trace "Outgoing pubsub message sent", msgId
elif fut.error != nil:
debug "Gossip message not sent", msgId, err = fut.error.msg
else:
debug "Unexpected future state for gossip", msgId, state = fut.state
proc broadcast*(node: Eth2Node, topic: string, msg: auto) =
inc nbc_gossip_messages_sent
let
data = snappy.encode(SSZ.encode(msg))
var futSnappy = node.pubsub.publish(topic & "_snappy", data)
traceMessage(futSnappy, gossipId(data))