allow to omit peerId and seqno (#372)

* allow to omit peerId and seqno

* small refactor

* wip

* fix message encoding

* improve rpc signature logic

* remove peerid from verify

* trace fixes

* fix message test

* fix gossip 1.0 tests

libp2p/protocols/pubsub/floodsub.nim

@@ -72,10 +72,19 @@ method rpcHandler*(f: FloodSub,
       trace "Dropping already-seen message", msgId, peer
       continue
 
-    if f.verifySignature and not msg.verify(peer.peerId):
+    if (msg.signature.len > 0 or f.verifySignature) and not msg.verify():
+      # always validate if signature is present or required
       debug "Dropping message due to failed signature verification", msgId, peer
       continue
 
+    if msg.seqno.len > 0 and msg.seqno.len != 8:
+      # if we have seqno should be 8 bytes long
+      debug "Dropping message due to invalid seqno length", msgId, peer
+      continue
+
+    # g.anonymize needs no evaluation when receiving messages
+    # as we have a "lax" policy and allow signed messages
+
     if not (await f.validate(msg)):
       trace "Dropping message due to failed validation", msgId, peer
       continue
@@ -129,7 +138,11 @@ method publish*(f: FloodSub,
 
   inc f.msgSeqno
   let
-    msg = Message.init(f.peerInfo, data, topic, f.msgSeqno, f.sign)
+    msg =
+      if f.anonymize:
+        Message.init(none(PeerInfo), data, topic, none(uint64), false)
+      else:
+        Message.init(some(f.peerInfo), data, topic, some(f.msgSeqno), f.sign)
     msgId = f.msgIdProvider(msg)
 
   trace "Created new message",

libp2p/protocols/pubsub/gossipsub.nim

@@ -1046,11 +1046,21 @@ method rpcHandler*(g: GossipSub,
 
     g.mcache.put(msgId, msg)
 
-    if g.verifySignature and not msg.verify(peer.peerId):
+    if (msg.signature.len > 0 or g.verifySignature) and not msg.verify():
+      # always validate if signature is present or required
       debug "Dropping message due to failed signature verification", msgId, peer
       g.punishPeer(peer, msg)
       continue
 
+    if msg.seqno.len > 0 and msg.seqno.len != 8:
+      # if we have seqno should be 8 bytes long
+      debug "Dropping message due to invalid seqno length", msgId, peer
+      g.punishPeer(peer, msg)
+      continue
+
+    # g.anonymize needs no evaluation when receiving messages
+    # as we have a "lax" policy and allow signed messages
+
     if not (await g.validate(msg)):
       debug "Dropping message due to failed validation", msgId, peer
       g.punishPeer(peer, msg)
@@ -1197,7 +1207,11 @@ method publish*(g: GossipSub,
 
   inc g.msgSeqno
   let
-    msg = Message.init(g.peerInfo, data, topic, g.msgSeqno, g.sign)
+    msg =
+      if g.anonymize:
+        Message.init(none(PeerInfo), data, topic, none(uint64), false)
+      else:
+        Message.init(some(g.peerInfo), data, topic, some(g.msgSeqno), g.sign)
     msgId = g.msgIdProvider(msg)
 
   logScope: msgId

libp2p/protocols/pubsub/gossipsub10.nim

@@ -451,10 +451,19 @@ method rpcHandler*(g: GossipSub,
 
     g.mcache.put(msgId, msg)
 
-    if g.verifySignature and not msg.verify(peer.peerId):
+    if (msg.signature.len > 0 or g.verifySignature) and not msg.verify():
+      # always validate if signature is present or required
       debug "Dropping message due to failed signature verification", msgId, peer
       continue
 
+    if msg.seqno.len > 0 and msg.seqno.len != 8:
+      # if we have seqno should be 8 bytes long
+      debug "Dropping message due to invalid seqno length", msgId, peer
+      continue
+
+    # g.anonymize needs no evaluation when receiving messages
+    # as we have a "lax" policy and allow signed messages
+
     if not (await g.validate(msg)):
       trace "Dropping message due to failed validation", msgId, peer
       continue
@@ -556,7 +565,11 @@ method publish*(g: GossipSub,
 
   inc g.msgSeqno
   let
-    msg = Message.init(g.peerInfo, data, topic, g.msgSeqno, g.sign)
+    msg =
+      if g.anonymize:
+        Message.init(none(PeerInfo), data, topic, none(uint64), false)
+      else:
+        Message.init(some(g.peerInfo), data, topic, some(g.msgSeqno), g.sign)
     msgId = g.msgIdProvider(msg)
 
   logScope: msgId

libp2p/protocols/pubsub/pubsub.nim

@@ -67,6 +67,7 @@ type
     observers: ref seq[PubSubObserver] # ref as in smart_ptr
     msgIdProvider*: MsgIdProvider      # Turn message into message id (not nil)
     msgSeqno*: uint64
+    anonymize*: bool                   # if we omit fromPeer and seqno from RPC messages we send
 
 method unsubscribePeer*(p: PubSub, peerId: PeerID) {.base.} =
   ## handle peer disconnects
@@ -329,6 +330,7 @@ proc init*[PubParams: object | bool](
   P: typedesc[PubSub],
   switch: Switch,
   triggerSelf: bool = false,
+  anonymize: bool = false,
   verifySignature: bool = true,
   sign: bool = true,
   msgIdProvider: MsgIdProvider = defaultMsgIdProvider,
@@ -338,6 +340,7 @@ proc init*[PubParams: object | bool](
       P(switch: switch,
         peerInfo: switch.peerInfo,
         triggerSelf: triggerSelf,
+        anonymize: anonymize,
         verifySignature: verifySignature,
         sign: sign,
         peers: initTable[PeerID, PubSubPeer](),
@@ -347,6 +350,7 @@ proc init*[PubParams: object | bool](
       P(switch: switch,
         peerInfo: switch.peerInfo,
         triggerSelf: triggerSelf,
+        anonymize: anonymize,
         verifySignature: verifySignature,
         sign: sign,
         peers: initTable[PeerID, PubSubPeer](),

libp2p/protocols/pubsub/rpc/message.nim

@@ -33,7 +33,7 @@ func defaultMsgIdProvider*(m: Message): string =
 proc sign*(msg: Message, privateKey: PrivateKey): CryptoResult[seq[byte]] =
   ok((? privateKey.sign(PubSubPrefix & encodeMessage(msg))).getBytes())
 
-proc verify*(m: Message, p: PeerID): bool =
+proc verify*(m: Message): bool =
   if m.signature.len > 0 and m.key.len > 0:
     var msg = m
     msg.signature = @[]
@@ -52,20 +52,26 @@ proc verify*(m: Message, p: PeerID): bool =
 
 proc init*(
     T: type Message,
-    peer: PeerInfo,
+    peer: Option[PeerInfo],
     data: seq[byte],
     topic: string,
-    seqno: uint64,
+    seqno: Option[uint64],
     sign: bool = true): Message {.gcsafe, raises: [CatchableError, Defect].} =
-  result = Message(
+  var msg = Message(data: data, topicIDs: @[topic])
-    fromPeer: peer.peerId,
-    data: data,
-    seqno: @(seqno.toBytesBE), # unefficient, fine for now
-    topicIDs: @[topic])
 
-  if sign:
+  # order matters, we want to include seqno in the signature
-    if peer.keyType != KeyType.HasPrivate:
+  if seqno.isSome: 
-      raise (ref CatchableError)(msg: "Cannot sign message without private key")
+    msg.seqno = @(seqno.get().toBytesBE())
 
-    result.signature = sign(result, peer.privateKey).tryGet()
+  if peer.isSome:
-    result.key = peer.privateKey.getKey().tryGet().getBytes().tryGet()
+    let peer = peer.get()
+    msg.fromPeer = peer.peerId
+    if sign:
+      if peer.keyType != KeyType.HasPrivate:
+        raise (ref CatchableError)(msg: "Cannot sign message without private key")
+      msg.signature = sign(msg, peer.privateKey).tryGet()
+      msg.key = peer.privateKey.getKey().tryGet().getBytes().tryGet()
+  elif sign:
+    raise (ref CatchableError)(msg: "Cannot sign message without peer info")
+
+  msg

tests/pubsub/testgossipinternal.nim

@@ -2,6 +2,7 @@ include ../../libp2p/protocols/pubsub/gossipsub
 
 {.used.}
 
+import options
 import unittest, bearssl
 import stew/byteutils
 import ../../libp2p/standard_setup
@@ -267,7 +268,7 @@ suite "GossipSub internal":
         let peerInfo = randomPeerInfo()
         conn.peerInfo = peerInfo
         inc seqno
-        let msg = Message.init(peerInfo, ("HELLO" & $i).toBytes(), topic, seqno, false)
+        let msg = Message.init(some(peerInfo), ("HELLO" & $i).toBytes(), topic, some(seqno), false)
         gossipSub.mcache.put(gossipSub.msgIdProvider(msg), msg)
 
       check gossipSub.fanout[topic].len == 15
@@ -321,7 +322,7 @@ suite "GossipSub internal":
         let peerInfo = randomPeerInfo()
         conn.peerInfo = peerInfo
         inc seqno
-        let msg = Message.init(peerInfo, ("HELLO" & $i).toBytes(), topic, seqno, false)
+        let msg = Message.init(some(peerInfo), ("HELLO" & $i).toBytes(), topic, some(seqno), false)
         gossipSub.mcache.put(gossipSub.msgIdProvider(msg), msg)
 
       let peers = gossipSub.getGossipPeers()
@@ -369,7 +370,7 @@ suite "GossipSub internal":
         let peerInfo = randomPeerInfo()
         conn.peerInfo = peerInfo
         inc seqno
-        let msg = Message.init(peerInfo, ("HELLO" & $i).toBytes(), topic, seqno, false)
+        let msg = Message.init(some(peerInfo), ("HELLO" & $i).toBytes(), topic, some(seqno), false)
         gossipSub.mcache.put(gossipSub.msgIdProvider(msg), msg)
 
       let peers = gossipSub.getGossipPeers()
@@ -417,7 +418,7 @@ suite "GossipSub internal":
         let peerInfo = randomPeerInfo()
         conn.peerInfo = peerInfo
         inc seqno
-        let msg = Message.init(peerInfo, ("bar" & $i).toBytes(), topic, seqno, false)
+        let msg = Message.init(some(peerInfo), ("bar" & $i).toBytes(), topic, some(seqno), false)
         gossipSub.mcache.put(gossipSub.msgIdProvider(msg), msg)
 
       let peers = gossipSub.getGossipPeers()

tests/pubsub/testgossipinternal10.nim

@@ -2,6 +2,7 @@ include ../../libp2p/protocols/pubsub/gossipsub10
 
 {.used.}
 
+import options
 import unittest, bearssl
 import stew/byteutils
 import ../../libp2p/standard_setup
@@ -244,7 +245,7 @@ suite "GossipSub internal":
         let peerInfo = randomPeerInfo()
         conn.peerInfo = peerInfo
         inc seqno
-        let msg = Message.init(peerInfo, ("HELLO" & $i).toBytes(), topic, seqno, false)
+        let msg = Message.init(some(peerInfo), ("HELLO" & $i).toBytes(), topic, some(seqno), false)
         gossipSub.mcache.put(gossipSub.msgIdProvider(msg), msg)
 
       check gossipSub.fanout[topic].len == 15
@@ -296,7 +297,7 @@ suite "GossipSub internal":
         let peerInfo = randomPeerInfo()
         conn.peerInfo = peerInfo
         inc seqno
-        let msg = Message.init(peerInfo, ("HELLO" & $i).toBytes(), topic, seqno, false)
+        let msg = Message.init(some(peerInfo), ("HELLO" & $i).toBytes(), topic, some(seqno), false)
         gossipSub.mcache.put(gossipSub.msgIdProvider(msg), msg)
 
       let peers = gossipSub.getGossipPeers()
@@ -341,7 +342,7 @@ suite "GossipSub internal":
         let peerInfo = randomPeerInfo()
         conn.peerInfo = peerInfo
         inc seqno
-        let msg = Message.init(peerInfo, ("HELLO" & $i).toBytes(), topic, seqno, false)
+        let msg = Message.init(some(peerInfo), ("HELLO" & $i).toBytes(), topic, some(seqno), false)
         gossipSub.mcache.put(gossipSub.msgIdProvider(msg), msg)
 
       let peers = gossipSub.getGossipPeers()
@@ -386,7 +387,7 @@ suite "GossipSub internal":
         let peerInfo = randomPeerInfo()
         conn.peerInfo = peerInfo
         inc seqno
-        let msg = Message.init(peerInfo, ("bar" & $i).toBytes(), topic, seqno, false)
+        let msg = Message.init(some(peerInfo), ("bar" & $i).toBytes(), topic, some(seqno), false)
         gossipSub.mcache.put(gossipSub.msgIdProvider(msg), msg)
 
       let peers = gossipSub.getGossipPeers()

tests/pubsub/testmessage.nim

@@ -2,6 +2,7 @@ import unittest
 
 {.used.}
 
+import options
 import ../../libp2p/[peerid, peerinfo,
                      crypto/crypto,
                      protocols/pubsub/rpc/message,
@@ -14,6 +15,6 @@ suite "Message":
     var seqno = 11'u64
     let
       peer = PeerInfo.init(PrivateKey.random(ECDSA, rng[]).get())
-      msg = Message.init(peer, @[], "topic", seqno, sign = true)
+      msg = Message.init(some(peer), @[], "topic", some(seqno), sign = true)
 
-    check verify(msg, peer.peerId)
+    check verify(msg)