feat(noise): added support to Waku Payload V2

tests/v2/test_waku_noise.nim

@@ -2,7 +2,9 @@
 
 import
   testutils/unittests,
+  ../../waku/v2/protocol/waku_message,
   ../../waku/v2/protocol/waku_noise/noise,
+  ../../waku/v2/node/waku_payload,
   ../test_helpers,
   std/tables
 
@@ -80,3 +82,42 @@ procSuite "Waku Noise":
 
     check:
       noisePublicKey == dec_pk
+
+  test "Encode/decode PayloadV2 to byte sequence":
+
+    let 
+      payload2 = randomPayloadV2(rng[])
+      encoded_payload = encodeV2(payload2)
+      decoded_payload = decodeV2(encoded_payload.get())
+
+    check: 
+      payload2 == decoded_payload.get()
+
+
+  test "Encode/Decode Waku2 payload (version 2) - ChaChaPoly Keyinfo":
+    # Encoding
+    let
+      version = 2'u32
+      payload = randomPayloadV2(rng[])
+      encodedPayload = encodePayloadV2(payload)
+
+    check encodedPayload.isOk()
+
+    let
+      msg = WakuMessage(payload: encodedPayload.get(), version: version)
+      pb =  msg.encode()
+
+    # Decoding
+    let msgDecoded = WakuMessage.init(pb.buffer)
+    check msgDecoded.isOk()
+
+    let
+      cipherState = randomChaChaPolyCipherState(rng[])
+      keyInfo = KeyInfo(kind: ChaChaPolyEncryption, cs: cipherState)
+      decoded = decodePayloadV2(msgDecoded.get(), keyInfo)
+
+    check:
+      decoded.isOk()
+      decoded.get() == payload
+
+  #TODO: add encrypt payload with ChaChaPoly

waku/v2/node/waku_payload.nim

@@ -4,7 +4,11 @@ import
   std/options,
   eth/keys,
   ../../whisper/whisper_types,
-  ../protocol/waku_message
+  ../protocol/waku_message,
+  ../protocol/waku_noise/noise
+
+import libp2p/crypto/[chacha20poly1305, curve25519]
+
 
 export whisper_types, keys, options
 
@@ -12,6 +16,7 @@ type
   KeyKind* = enum
     Symmetric
     Asymmetric
+    ChaChaPolyEncryption
     None
 
   KeyInfo* = object
@@ -20,6 +25,8 @@ type
       symKey*: SymKey
     of Asymmetric:
       privKey*: PrivateKey
+    of ChaChaPolyEncryption:
+      cs*: ChaChaPolyCipherState
     of None:
       discard
 
@@ -56,7 +63,7 @@ proc decodePayload*(message: WakuMessage, keyInfo: KeyInfo):
         return ok(decoded.get())
       else:
         return err("Couldn't decrypt using asymmetric key")
-    of None:
+    else:
       discard
   else:
     return err("Unsupported WakuMessage version")
@@ -77,3 +84,29 @@ proc encode*(payload: Payload, version: uint32, rng: var BrHmacDrbgContext):
       return err("Couldn't encode the payload")
   else:
     return err("Unsupported WakuMessage version")
+
+
+proc decodePayloadV2*(message: WakuMessage, keyInfo: KeyInfo):
+    WakuResult[PayloadV2] =
+  case message.version
+  of 2:
+    case keyInfo.kind
+    of ChaChaPolyEncryption:
+      let decoded = decodeV2(message.payload)#, keyInfo.cs)
+      if decoded.isSome():
+        return ok(decoded.get())
+      else:
+        return err("Couldn't decrypt using ChaChaPoly Cipher State")
+    else:
+      discard
+  else:
+    return err("Key info doesn't match v2 payloads")
+
+
+proc encodePayloadV2*(payload: PayloadV2):
+    WakuResult[seq[byte]] =
+  let encoded = encodeV2(payload)
+  if encoded.isSome():
+    return ok(encoded.get())
+  else:
+    return err("Couldn't encode the payload")

waku/v2/protocol/waku_noise/noise.nim

@@ -132,7 +132,6 @@ proc serializeNoisePublicKey*(noisePublicKey: NoisePublicKey): seq[byte] =
   result.add noisePublicKey.flag
   result.add noisePublicKey.pk
 
-#TODO: strip pk_auth if pk not encrypted
 proc intoNoisePublicKey*(serializedNoisePublicKey: seq[byte]): NoisePublicKey =
   result.flag = serializedNoisePublicKey[0]
   assert result.flag == 0 or result.flag == 1
@@ -168,3 +167,112 @@ proc decryptNoisePublicKey*(cs: ChaChaPolyCipherState, noisePublicKey: NoisePubl
       debug "Public key is not encrypted."
     debug "Public key is left unchanged"
     result = noisePublicKey
+
+
+
+
+
+# Payload functions
+type
+  PayloadV2* = object
+    protocol_id: uint8
+    handshake_message: seq[NoisePublicKey]
+    transport_message: seq[byte]
+
+
+proc `==`(p1, p2: PayloadV2): bool =
+  result =  (p1.protocol_id == p2.protocol_id) and 
+            (p1.handshake_message == p2.handshake_message) and 
+            (p1.transport_message == p2.transport_message) 
+  
+
+
+proc randomPayloadV2*(rng: var BrHmacDrbgContext): PayloadV2 =
+  var protocol_id = newSeq[byte](1)
+  brHmacDrbgGenerate(rng, protocol_id)
+  result.protocol_id = protocol_id[0].uint8
+  result.handshake_message = @[genNoisePublicKey(rng), genNoisePublicKey(rng), genNoisePublicKey(rng)]
+  result.transport_message = newSeq[byte](128)
+  brHmacDrbgGenerate(rng, result.transport_message)
+
+
+proc encodeV2*(self: PayloadV2): Option[seq[byte]] =
+
+  #We collect public keys contained in the handshake message
+  var
+    ser_handshake_message_len: int = 0
+    ser_handshake_message = newSeqOfCap[byte](256)
+    ser_pk: seq[byte]
+  for pk in self.handshake_message:
+    ser_pk = serializeNoisePublicKey(pk)
+    ser_handshake_message_len +=  ser_pk.len
+    ser_handshake_message.add ser_pk
+
+
+  #RFC: handshake-message-len is 1 byte
+  if ser_handshake_message_len > 256:
+    debug "Payload malformed: too many public keys contained in the handshake message"
+    return none(seq[byte])
+
+  let transport_message_len = self.transport_message.len
+  #let transport_message_len_len = ceil(log(transport_message_len, 8)).int
+
+  var payload = newSeqOfCap[byte](1 + #self.protocol_id.len +              
+                                  1 + #ser_handshake_message_len 
+                                  ser_handshake_message_len +        
+                                  8 + #transport_message_len
+                                  transport_message_len #self.transport_message
+                                  )
+  
+  
+  payload.add self.protocol_id.byte
+  payload.add ser_handshake_message_len.byte
+  payload.add ser_handshake_message
+  payload.add toBytesLE(transport_message_len.uint64)
+  payload.add self.transport_message
+
+  return some(payload)
+
+
+
+#Decode Noise handshake payload
+proc decodeV2*(payload: seq[byte]): Option[PayloadV2] =
+  var res: PayloadV2
+
+  var i: uint64 = 0
+  res.protocol_id = payload[i].uint8
+  i+=1
+
+  var handshake_message_len = payload[i].uint64
+  i+=1
+
+  var handshake_message: seq[NoisePublicKey]
+
+  var 
+    flag: byte
+    pk_len: uint64
+    written: uint64 = 0
+
+  while written != handshake_message_len:
+    #Note that flag can be used to add support to multiple Elliptic Curve arithmetics..
+    flag = payload[i]
+    if flag == 0:
+      pk_len = 1 + Curve25519Key.len
+      handshake_message.add intoNoisePublicKey(payload[i..<i+pk_len])
+      i += pk_len
+      written += pk_len
+    if flag == 1:
+      pk_len = 1 + Curve25519Key.len + ChaChaPolyTag.len
+      handshake_message.add intoNoisePublicKey(payload[i..<i+pk_len])
+      i += pk_len
+      written += pk_len
+
+  res.handshake_message = handshake_message
+
+  let transport_message_len = fromBytesLE(uint64, payload[i..(i+8-1)])
+  i+=8
+
+  res.transport_message = payload[i..i+transport_message_len-1]
+  i+=transport_message_len
+
+  return some(res)