nwaku/waku/waku_relay/protocol.nim

512 lines
17 KiB
Nim
Raw Permalink Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

## Waku Relay module. Thin layer on top of GossipSub.
##
## See https://github.com/vacp2p/specs/blob/master/specs/waku/v2/waku-relay.md
## for spec.
{.push raises: [].}
import
std/strformat,
stew/byteutils,
results,
sequtils,
chronos,
chronicles,
metrics,
libp2p/multihash,
libp2p/protocols/pubsub/pubsub,
libp2p/protocols/pubsub/gossipsub,
libp2p/protocols/pubsub/rpc/messages,
libp2p/stream/connection,
libp2p/switch
import ../waku_core, ./message_id, ../node/delivery_monitor/publish_observer
from ../waku_core/codecs import WakuRelayCodec
export WakuRelayCodec
logScope:
topics = "waku relay"
# see: https://github.com/libp2p/specs/blob/master/pubsub/gossipsub/gossipsub-v1.1.md#overview-of-new-parameters
const TopicParameters = TopicParams(
topicWeight: 1,
# p1: favours peers already in the mesh
timeInMeshWeight: 0.01,
timeInMeshQuantum: 1.seconds,
timeInMeshCap: 10.0,
# p2: rewards fast peers
firstMessageDeliveriesWeight: 1.0,
firstMessageDeliveriesDecay: 0.5,
firstMessageDeliveriesCap: 10.0,
# p3: penalizes lazy peers. safe low value
meshMessageDeliveriesWeight: 0.0,
meshMessageDeliveriesDecay: 0.0,
meshMessageDeliveriesCap: 0,
meshMessageDeliveriesThreshold: 0,
meshMessageDeliveriesWindow: 0.milliseconds,
meshMessageDeliveriesActivation: 0.seconds,
# p3b: tracks history of prunes
meshFailurePenaltyWeight: 0.0,
meshFailurePenaltyDecay: 0.0,
# p4: penalizes invalid messages. highly penalize
# peers sending wrong messages
invalidMessageDeliveriesWeight: -100.0,
invalidMessageDeliveriesDecay: 0.5,
)
declareCounter waku_relay_network_bytes,
"total traffic per topic, distinct gross/net and direction",
labels = ["topic", "type", "direction"]
# see: https://rfc.vac.dev/spec/29/#gossipsub-v10-parameters
const GossipsubParameters = GossipSubParams.init(
pruneBackoff = chronos.minutes(1),
unsubscribeBackoff = chronos.seconds(5),
floodPublish = true,
gossipFactor = 0.25,
d = 6,
dLow = 4,
dHigh = 8,
dScore = 6,
dOut = 3,
dLazy = 6,
heartbeatInterval = chronos.seconds(1),
historyLength = 6,
historyGossip = 3,
fanoutTTL = chronos.minutes(1),
seenTTL = chronos.minutes(2),
# no gossip is sent to peers below this score
gossipThreshold = -100,
# no self-published msgs are sent to peers below this score
publishThreshold = -1000,
# used to trigger disconnections + ignore peer if below this score
graylistThreshold = -10000,
# grafts better peers if the mesh median score drops below this. unset.
opportunisticGraftThreshold = 0,
# how often peer scoring is updated
decayInterval = chronos.seconds(12),
# below this we consider the parameter to be zero
decayToZero = 0.01,
# remember peer score during x after it disconnects
retainScore = chronos.minutes(10),
# p5: application specific, unset
appSpecificWeight = 0.0,
# p6: penalizes peers sharing more than threshold ips
ipColocationFactorWeight = -50.0,
ipColocationFactorThreshold = 5.0,
# p7: penalizes bad behaviour (weight and decay)
behaviourPenaltyWeight = -10.0,
behaviourPenaltyDecay = 0.986,
# triggers disconnections of bad peers aka score <graylistThreshold
disconnectBadPeers = true,
)
type
WakuRelayResult*[T] = Result[T, string]
WakuRelayHandler* = proc(pubsubTopic: PubsubTopic, message: WakuMessage): Future[void] {.
gcsafe, raises: [Defect]
.}
WakuValidatorHandler* = proc(
pubsubTopic: PubsubTopic, message: WakuMessage
): Future[ValidationResult] {.gcsafe, raises: [Defect].}
WakuRelay* = ref object of GossipSub
# seq of tuples: the first entry in the tuple contains the validators are called for every topic
# the second entry contains the error messages to be returned when the validator fails
wakuValidators: seq[tuple[handler: WakuValidatorHandler, errorMessage: string]]
# a map of validators to error messages to return when validation fails
validatorInserted: Table[PubsubTopic, bool]
publishObservers: seq[PublishObserver]
proc initProtocolHandler(w: WakuRelay) =
proc handler(conn: Connection, proto: string) {.async.} =
## main protocol handler that gets triggered on every
## connection for a protocol string
## e.g. ``/wakusub/0.0.1``, etc...
debug "Incoming WakuRelay connection", connection = conn, protocol = proto
try:
await w.handleConn(conn, proto)
except CancelledError:
# This is top-level procedure which will work as separate task, so it
# do not need to propogate CancelledError.
error "Unexpected cancellation in relay handler",
conn = conn, error = getCurrentExceptionMsg()
except CatchableError:
error "WakuRelay handler leaks an error",
conn = conn, error = getCurrentExceptionMsg()
# XXX: Handler hijack GossipSub here?
w.handler = handler
w.codec = WakuRelayCodec
proc logMessageInfo*(
w: WakuRelay,
remotePeerId: string,
topic: string,
msg_id_short: string,
msg: WakuMessage,
onRecv: bool,
) =
let msg_hash = computeMessageHash(topic, msg).to0xHex()
if onRecv:
notice "received relay message",
my_peer_id = w.switch.peerInfo.peerId,
msg_hash = msg_hash,
msg_id = msg_id_short,
from_peer_id = remotePeerId,
topic = topic,
receivedTime = getNowInNanosecondTime(),
payloadSizeBytes = msg.payload.len
else:
notice "sent relay message",
my_peer_id = w.switch.peerInfo.peerId,
msg_hash = msg_hash,
msg_id = msg_id_short,
to_peer_id = remotePeerId,
topic = topic,
sentTime = getNowInNanosecondTime(),
payloadSizeBytes = msg.payload.len
proc initRelayObservers(w: WakuRelay) =
proc decodeRpcMessageInfo(
peer: PubSubPeer, msg: Message
): Result[
tuple[msgId: string, topic: string, wakuMessage: WakuMessage, msgSize: int], void
] =
let msg_id = w.msgIdProvider(msg).valueOr:
warn "Error generating message id",
my_peer_id = w.switch.peerInfo.peerId,
from_peer_id = peer.peerId,
pubsub_topic = msg.topic,
error = $error
return err()
let msg_id_short = shortLog(msg_id)
let wakuMessage = WakuMessage.decode(msg.data).valueOr:
warn "Error decoding to Waku Message",
my_peer_id = w.switch.peerInfo.peerId,
msg_id = msg_id_short,
from_peer_id = peer.peerId,
pubsub_topic = msg.topic,
error = $error
return err()
let msgSize = msg.data.len + msg.topic.len
return ok((msg_id_short, msg.topic, wakuMessage, msgSize))
proc updateMetrics(
peer: PubSubPeer,
pubsub_topic: string,
msg: WakuMessage,
msgSize: int,
onRecv: bool,
) =
if onRecv:
waku_relay_network_bytes.inc(
msgSize.int64, labelValues = [pubsub_topic, "gross", "in"]
)
else:
# sent traffic can only be "net"
# TODO: If we can measure unsuccessful sends would mean a possible distinction between gross/net
waku_relay_network_bytes.inc(
msgSize.int64, labelValues = [pubsub_topic, "net", "out"]
)
proc onRecv(peer: PubSubPeer, msgs: var RPCMsg) =
for msg in msgs.messages:
let (msg_id_short, topic, wakuMessage, msgSize) = decodeRpcMessageInfo(peer, msg).valueOr:
continue
# message receive log happens in onValidated observer as onRecv is called before checks
updateMetrics(peer, topic, wakuMessage, msgSize, onRecv = true)
discard
proc onValidated(peer: PubSubPeer, msg: Message, msgId: MessageId) =
let msg_id_short = shortLog(msgId)
let wakuMessage = WakuMessage.decode(msg.data).valueOr:
warn "onValidated: failed decoding to Waku Message",
my_peer_id = w.switch.peerInfo.peerId,
msg_id = msg_id_short,
from_peer_id = peer.peerId,
pubsub_topic = msg.topic,
error = $error
return
logMessageInfo(
w, shortLog(peer.peerId), msg.topic, msg_id_short, wakuMessage, onRecv = true
)
proc onSend(peer: PubSubPeer, msgs: var RPCMsg) =
for msg in msgs.messages:
let (msg_id_short, topic, wakuMessage, msgSize) = decodeRpcMessageInfo(peer, msg).valueOr:
warn "onSend: failed decoding RPC info",
my_peer_id = w.switch.peerInfo.peerId, to_peer_id = peer.peerId
continue
logMessageInfo(
w, shortLog(peer.peerId), topic, msg_id_short, wakuMessage, onRecv = false
)
updateMetrics(peer, topic, wakuMessage, msgSize, onRecv = false)
let administrativeObserver =
PubSubObserver(onRecv: onRecv, onSend: onSend, onValidated: onValidated)
w.addObserver(administrativeObserver)
proc new*(
T: type WakuRelay, switch: Switch, maxMessageSize = int(DefaultMaxWakuMessageSize)
): WakuRelayResult[T] =
## maxMessageSize: max num bytes that are allowed for the WakuMessage
var w: WakuRelay
try:
w = WakuRelay.init(
switch = switch,
anonymize = true,
verifySignature = false,
sign = false,
triggerSelf = true,
msgIdProvider = defaultMessageIdProvider,
maxMessageSize = maxMessageSize,
parameters = GossipsubParameters,
)
procCall GossipSub(w).initPubSub()
w.initProtocolHandler()
w.initRelayObservers()
except InitializationError:
return err("initialization error: " & getCurrentExceptionMsg())
return ok(w)
proc addValidator*(
w: WakuRelay, handler: WakuValidatorHandler, errorMessage: string = ""
) {.gcsafe.} =
w.wakuValidators.add((handler, errorMessage))
proc addPublishObserver*(w: WakuRelay, obs: PublishObserver) =
## Observer when the api client performed a publish operation. This
## is initially aimed for bringing an additional layer of delivery reliability thanks
## to store
w.publishObservers.add(obs)
proc addObserver*(w: WakuRelay, observer: PubSubObserver) {.gcsafe.} =
## Observes when a message is sent/received from the GossipSub PoV
procCall GossipSub(w).addObserver(observer)
method start*(w: WakuRelay) {.async, base.} =
debug "start"
await procCall GossipSub(w).start()
method stop*(w: WakuRelay) {.async, base.} =
debug "stop"
await procCall GossipSub(w).stop()
proc isSubscribed*(w: WakuRelay, topic: PubsubTopic): bool =
GossipSub(w).topics.hasKey(topic)
proc subscribedTopics*(w: WakuRelay): seq[PubsubTopic] =
return toSeq(GossipSub(w).topics.keys())
proc generateOrderedValidator(w: WakuRelay): auto {.gcsafe.} =
# rejects messages that are not WakuMessage
let wrappedValidator = proc(
pubsubTopic: string, message: messages.Message
): Future[ValidationResult] {.async.} =
# can be optimized by checking if the message is a WakuMessage without allocating memory
# see nim-libp2p protobuf library
let msg = WakuMessage.decode(message.data).valueOr:
error "protocol generateOrderedValidator reject decode error",
pubsubTopic = pubsubTopic, error = $error
return ValidationResult.Reject
# now sequentially validate the message
for (validator, errorMessage) in w.wakuValidators:
let validatorRes = await validator(pubsubTopic, msg)
if validatorRes != ValidationResult.Accept:
let msgHash = computeMessageHash(pubsubTopic, msg).to0xHex()
error "protocol generateOrderedValidator reject waku validator",
msg_hash = msgHash,
pubsubTopic = pubsubTopic,
contentTopic = msg.contentTopic,
validatorRes = validatorRes,
error = errorMessage
return validatorRes
return ValidationResult.Accept
return wrappedValidator
proc validateMessage*(
w: WakuRelay, pubsubTopic: string, msg: WakuMessage
): Future[Result[void, string]] {.async.} =
let messageSizeBytes = msg.encode().buffer.len
let msgHash = computeMessageHash(pubsubTopic, msg).to0xHex()
if messageSizeBytes > w.maxMessageSize:
let message = fmt"Message size exceeded maximum of {w.maxMessageSize} bytes"
error "too large Waku message",
msg_hash = msgHash,
error = message,
messageSizeBytes = messageSizeBytes,
maxMessageSize = w.maxMessageSize
return err(message)
for (validator, message) in w.wakuValidators:
let validatorRes = await validator(pubsubTopic, msg)
if validatorRes != ValidationResult.Accept:
if message.len > 0:
error "invalid Waku message", msg_hash = msgHash, error = message
return err(message)
else:
## This should never happen
error "uncertain invalid Waku message", msg_hash = msgHash, error = message
return err("validator failed")
return ok()
proc subscribe*(
w: WakuRelay, pubsubTopic: PubsubTopic, handler: WakuRelayHandler
): TopicHandler =
debug "subscribe", pubsubTopic = pubsubTopic
# We need to wrap the handler since gossipsub doesnt understand WakuMessage
let wrappedHandler = proc(
pubsubTopic: string, data: seq[byte]
): Future[void] {.gcsafe, raises: [].} =
let decMsg = WakuMessage.decode(data)
if decMsg.isErr():
# fine if triggerSelf enabled, since validators are bypassed
error "failed to decode WakuMessage, validator passed a wrong message",
pubsubTopic = pubsubTopic, error = decMsg.error
let fut = newFuture[void]()
fut.complete()
return fut
else:
# this subscription handler is called once for every validated message
# that will be relayed, hence this is the place we can count net incoming traffic
waku_relay_network_bytes.inc(
data.len.int64 + pubsubTopic.len.int64, labelValues = [pubsubTopic, "net", "in"]
)
return handler(pubsubTopic, decMsg.get())
# Add the ordered validator to the topic
# This assumes that if `w.validatorInserted.hasKey(pubSubTopic) is true`, it contains the ordered validator.
# Otherwise this might lead to unintended behaviour.
if not w.validatorInserted.hasKey(pubSubTopic):
procCall GossipSub(w).addValidator(pubSubTopic, w.generateOrderedValidator())
w.validatorInserted[pubSubTopic] = true
# set this topic parameters for scoring
w.topicParams[pubsubTopic] = TopicParameters
# subscribe to the topic with our wrapped handler
procCall GossipSub(w).subscribe(pubsubTopic, wrappedHandler)
return wrappedHandler
proc unsubscribeAll*(w: WakuRelay, pubsubTopic: PubsubTopic) =
## Unsubscribe all handlers on this pubsub topic
debug "unsubscribe all", pubsubTopic = pubsubTopic
procCall GossipSub(w).unsubscribeAll(pubsubTopic)
w.validatorInserted.del(pubsubTopic)
proc unsubscribe*(w: WakuRelay, pubsubTopic: PubsubTopic, handler: TopicHandler) =
## Unsubscribe this handler on this pubsub topic
debug "unsubscribe", pubsubTopic = pubsubTopic
procCall GossipSub(w).unsubscribe(pubsubTopic, handler)
proc publish*(
w: WakuRelay, pubsubTopic: PubsubTopic, message: WakuMessage
): Future[int] {.async.} =
let data = message.encode().buffer
let msgHash = computeMessageHash(pubsubTopic, message).to0xHex()
notice "start publish Waku message", msg_hash = msgHash, pubsubTopic = pubsubTopic
let relayedPeerCount = await procCall GossipSub(w).publish(pubsubTopic, data)
if relayedPeerCount > 0:
for obs in w.publishObservers:
obs.onMessagePublished(pubSubTopic, message)
return relayedPeerCount
proc getNumPeersInMesh*(w: WakuRelay, pubsubTopic: PubsubTopic): Result[int, string] =
## Returns the number of peers in a mesh defined by the passed pubsub topic.
## The 'mesh' atribute is defined in the GossipSub ref object.
if not w.mesh.hasKey(pubsubTopic):
return err(
"getNumPeersInMesh - there is no mesh peer for the given pubsub topic: " &
pubsubTopic
)
let peersRes = catch:
w.mesh[pubsubTopic]
let peers: HashSet[PubSubPeer] = peersRes.valueOr:
return
err("getNumPeersInMesh - exception accessing " & pubsubTopic & ": " & error.msg)
return ok(peers.len)
proc getNumConnectedPeers*(
w: WakuRelay, pubsubTopic: PubsubTopic
): Result[int, string] =
## Returns the number of connected peers and subscribed to the passed pubsub topic.
## The 'gossipsub' atribute is defined in the GossipSub ref object.
if pubsubTopic == "":
## Return all the connected peers
var numConnPeers = 0
for k, v in w.gossipsub:
numConnPeers.inc(v.len)
return ok(numConnPeers)
if not w.gossipsub.hasKey(pubsubTopic):
return err(
"getNumConnectedPeers - there is no gossipsub peer for the given pubsub topic: " &
pubsubTopic
)
let peersRes = catch:
w.gossipsub[pubsubTopic]
let peers: HashSet[PubSubPeer] = peersRes.valueOr:
return err(
"getNumConnectedPeers - exception accessing " & pubsubTopic & ": " & error.msg
)
return ok(peers.len)
proc getSubscribedTopics*(w: WakuRelay): seq[PubsubTopic] =
## Returns a seq containing the current list of subscribed topics
var topics: seq[PubsubTopic]
for t in w.validatorInserted.keys():
topics.add(t)
return topics