Added packet encoding tests

eth/p2p/discoveryv5/encoding.nim

@@ -246,7 +246,8 @@ proc decodeEncrypted*(c: var Codec, fromId: NodeID, fromAddr: Address, input: se
     result = decodePacketBody(body[0], body.toOpenArray(1, body.high), packet)
 
 proc newRequestId*(): RequestId =
-  randomBytes(result)
+  if randomBytes(addr result, sizeof(result)) != sizeof(result):
+    raise newException(Exception, "Could not randomize bytes") # TODO:
 
 proc numFields(T: typedesc): int =
   for k, v in fieldPairs(default(T)): inc result
@@ -265,9 +266,3 @@ proc encodePacket*[T: SomePacket](p: T, reqId: RequestId): seq[byte] =
 
 proc encodePacket*[T: SomePacket](p: T): seq[byte] =
   encodePacket(p, newRequestId())
-
-proc makePingPacket*(enrSeq: uint64): seq[byte] =
-  encodePacket(PingPacket(enrSeq: enrSeq))
-
-proc makeFindnodePacket*(distance: uint32): seq[byte] =
-  encodePacket(FindNodePacket(distance: distance))

eth/p2p/discoveryv5/types.nim

@@ -28,7 +28,7 @@ type
     regconfirmation = 0x07
     topicquery = 0x08
 
-  RequestId* = array[8, byte]
+  RequestId* = uint64
 
   PingPacket* = object
     enrSeq*: uint64

tests/p2p/test_discv5_encoding.nim

@@ -0,0 +1,44 @@
+import unittest
+import eth/p2p/discoveryv5/[types, encoding, enr]
+import eth/rlp, stew/byteutils
+
+# According to test vectors:
+# https://github.com/ethereum/devp2p/blob/master/discv5/discv5-wire-test-vectors.md
+
+suite "Discovery v5 Protocol Message Encodings":
+  test "Ping Request":
+    var p: PingPacket
+    p.enrSeq = 1
+    var reqId: RequestId = 1
+    check encodePacket(p, reqId).toHex == "01c20101"
+
+  test "Pong Response":
+    var p: PongPacket
+    p.enrSeq = 1
+    p.port = 5000
+    p.ip = @[127.byte, 0, 0, 1]
+    var reqId: RequestId = 1
+    check encodePacket(p, reqId).toHex == "02ca0101847f000001821388"
+
+  test "FindNode Request":
+    var p: FindNodePacket
+    p.distance = 0x0100
+    var reqId: RequestId = 1
+    check encodePacket(p, reqId).toHex == "03c401820100"
+
+  test "Nodes Response (empty)":
+    var p: NodesPacket
+    p.total = 0x1
+    var reqId: RequestId = 1
+    check encodePacket(p, reqId).toHex == "04c30101c0"
+
+  test "Nodes Response (multiple)":
+    var p: NodesPacket
+    p.total = 0x1
+    var e1, e2: Record
+    check e1.fromURI("enr:-HW4QBzimRxkmT18hMKaAL3IcZF1UcfTMPyi3Q1pxwZZbcZVRI8DC5infUAB_UauARLOJtYTxaagKoGmIjzQxO2qUygBgmlkgnY0iXNlY3AyNTZrMaEDymNMrg1JrLQB2KTGtv6MVbcNEVv0AHacwUAPMljNMTg")
+    check e2.fromURI("enr:-HW4QNfxw543Ypf4HXKXdYxkyzfcxcO-6p9X986WldfVpnVTQX1xlTnWrktEWUbeTZnmgOuAY_KUhbVV1Ft98WoYUBMBgmlkgnY0iXNlY3AyNTZrMaEDDiy3QkHAxPyOgWbxp5oF1bDdlYE6dLCUUp8xfVw50jU")
+
+    p.enrs = @[e1, e2]
+    var reqId: RequestId = 1
+    check encodePacket(p, reqId).toHex == "04f8f20101f8eef875b8401ce2991c64993d7c84c29a00bdc871917551c7d330fca2dd0d69c706596dc655448f030b98a77d4001fd46ae0112ce26d613c5a6a02a81a6223cd0c4edaa53280182696482763489736563703235366b31a103ca634cae0d49acb401d8a4c6b6fe8c55b70d115bf400769cc1400f3258cd3138f875b840d7f1c39e376297f81d7297758c64cb37dcc5c3beea9f57f7ce9695d7d5a67553417d719539d6ae4b445946de4d99e680eb8063f29485b555d45b7df16a1850130182696482763489736563703235366b31a1030e2cb74241c0c4fc8e8166f1a79a05d5b0dd95813a74b094529f317d5c39d235"