Fix logDistance for BE arch and remove toBytes for NodeId (#427)

toBytes for NodeId wasn't selected by compiler byt if it does
get selected, it will fail on the test cases due to the
countdown that is done in logDistance.
Set to toBytesBE properly now and do countup, that should make
it correct also for BE architecture.

Removed toBytes to avoid confusion and avoid this one being
selected ever. The only place toBytes for NodeId was used is in
sessions.nim makeKey func and there also the stint one
(thus native endianness) was selected in Nim 1.2.x.
Native endianness is fine there as it is only an internal
representation.

eth/p2p/discoveryv5/encoding.nim

@@ -236,7 +236,7 @@ proc encodeWhoareyouPacket*(rng: var BrHmacDrbgContext, c: var Codec,
   # authdata
   var authdata: seq[byte]
   authdata.add(idNonce)
-  authdata.add(recordSeq.tobytesBE)
+  authdata.add(recordSeq.toBytesBE)
 
   # static-header
   let staticHeader = encodeStaticHeader(Flag.Whoareyou, requestNonce,

eth/p2p/discoveryv5/node.nim

@@ -88,9 +88,6 @@ proc random*(T: type NodeId, rng: var BrHmacDrbgContext): T =
 
   id
 
-func toBytes*(id: NodeId): array[32, byte] =
-  id.toByteArrayBE()
-
 func `$`*(id: NodeId): string =
   id.toHex()
 

eth/p2p/discoveryv5/routing_table.nim

@@ -104,10 +104,10 @@ func logDistance*(a, b: NodeId): uint16 =
   ## is rather the log base 2 of the distance + 1, as else the 0 value can not
   ## be used (e.g. by FindNode call to return peer its own ENR)
   ## For NodeId of 256 bits, range is 0-256.
-  let a = a.toBytes
-  let b = b.toBytes
+  let a = a.toBytesBE
+  let b = b.toBytesBE
   var lz = 0
-  for i in countdown(a.len - 1, 0):
+  for i in 0..<a.len:
     let x = a[i] xor b[i]
     if x == 0:
       lz += 8

tests/p2p/test_discoveryv5.nim

@@ -82,15 +82,55 @@ procSuite "Discovery v5 Tests":
       check logDistance(parse(targetId, UInt256, 16), parse(id, UInt256, 16)) == d
 
   test "Distance check with keys":
+    # Values for this test are taken from
+    # https://github.com/ethereum/go-ethereum/blob/d8ff53dfb8a516f47db37dbc7fd7ad18a1e8a125/p2p/discover/v4_lookup_test.go#L176
     const
       targetKey = "5d485bdcbe9bc89314a10ae9231e429d33853e3a8fa2af39f5f827370a2e4185e344ace5d16237491dad41f278f1d3785210d29ace76cd627b9147ee340b1125"
       testValues = [
         ("29738ba0c1a4397d6a65f292eee07f02df8e58d41594ba2be3cf84ce0fc58169", 251'u16),
+        ("511b1686e4e58a917f7f848e9bf5539d206a68f5ad6b54b552c2399fe7d174ae", 251'u16),
+        ("d09e5eaeec0fd596236faed210e55ef45112409a5aa7f3276d26646080dcfaeb", 251'u16),
+        ("c1e20dbbf0d530e50573bd0a260b32ec15eb9190032b4633d44834afc8afe578", 251'u16),
+        ("ed5f38f5702d92d306143e5d9154fb21819777da39af325ea359f453d179e80b", 251'u16),
+
         ("1c9b1cafbec00848d2c174b858219914b42a7d5c9359b1ca03fd650e8239ae94", 252'u16),
+        ("e0e1e8db4a6f13c1ffdd3e96b72fa7012293ced187c9dcdcb9ba2af37a46fa10", 252'u16),
+        ("3d53823e0a0295cb09f3e11d16c1b44d07dd37cec6f739b8df3a590189fe9fb9", 252'u16),
+
         ("2d0511ae9bf590166597eeab86b6f27b1ab761761eaea8965487b162f8703847", 253'u16),
+        ("6cfbd7b8503073fc3dbdb746a7c672571648d3bd15197ccf7f7fef3d904f53a2", 253'u16),
+        ("a30599b12827b69120633f15b98a7f6bc9fc2e9a0fd6ae2ebb767c0e64d743ab", 253'u16),
+        ("14a98db9b46a831d67eff29f3b85b1b485bb12ae9796aea98d91be3dc78d8a91", 253'u16),
+        ("2369ff1fc1ff8ca7d20b17e2673adc3365c3674377f21c5d9dafaff21fe12e24", 253'u16),
+        ("9ae91101d6b5048607f41ec0f690ef5d09507928aded2410aabd9237aa2727d7", 253'u16),
+        ("05e3c59090a3fd1ae697c09c574a36fcf9bedd0afa8fe3946f21117319ca4973", 253'u16),
+        ("06f31c5ea632658f718a91a1b1b9ae4b7549d7b3bc61cbc2be5f4a439039f3ad", 253'u16),
+
         ("dec742079ec00ff4ec1284d7905bc3de2366f67a0769431fd16f80fd68c58a7c", 254'u16),
+        ("ff02c8861fa12fbd129d2a95ea663492ef9c1e51de19dcfbbfe1c59894a28d2b", 254'u16),
+        ("4dded9e4eefcbce4262be4fd9e8a773670ab0b5f448f286ec97dfc8cf681444a", 254'u16),
+        ("750d931e2a8baa2c9268cb46b7cd851f4198018bed22f4dceb09dd334a2395f6", 254'u16),
+        ("ce1435a956a98ffec484cd11489c4f165cf1606819ab6b521cee440f0c677e9e", 254'u16),
+        ("996e7f8d1638be92d7328b4770f47e5420fc4bafecb4324fd33b1f5d9f403a75", 254'u16),
+        ("46bd1eddcf6431bea66fc19ebc45df191c1c7d6ed552dcdc7392885009c322f0", 254'u16),
+
         ("da8645f90826e57228d9ea72aff84500060ad111a5d62e4af831ed8e4b5acfb8", 255'u16),
-        ("8c5b422155d33ea8e9d46f71d1ad3e7b24cb40051413ffa1a81cff613d243ba9", 256'u16)
+        ("3c944c5d9af51d4c1d43f5d0f3a1a7ef65d5e82744d669b58b5fed242941a566", 255'u16),
+        ("5ebcde76f1d579eebf6e43b0ffe9157e65ffaa391175d5b9aa988f47df3e33da", 255'u16),
+        ("97f78253a7d1d796e4eaabce721febcc4550dd68fb11cc818378ba807a2cb7de", 255'u16),
+        ("a38cd7dc9b4079d1c0406afd0fdb1165c285f2c44f946eca96fc67772c988c7d", 255'u16),
+        ("d64cbb3ffdf712c372b7a22a176308ef8f91861398d5dbaf326fd89c6eaeef1c", 255'u16),
+        ("d269609743ef29d6446e3355ec647e38d919c82a4eb5837e442efd7f4218944f", 255'u16),
+        ("d8f7bcc4a530efde1d143717007179e0d9ace405ddaaf151c4d863753b7fd64c", 255'u16),
+
+        ("8c5b422155d33ea8e9d46f71d1ad3e7b24cb40051413ffa1a81cff613d243ba9", 256'u16),
+        ("937b1af801def4e8f5a3a8bd225a8bcff1db764e41d3e177f2e9376e8dd87233", 256'u16),
+        ("120260dce739b6f71f171da6f65bc361b5fad51db74cf02d3e973347819a6518", 256'u16),
+        ("1fa56cf25d4b46c2bf94e82355aa631717b63190785ac6bae545a88aadc304a9", 256'u16),
+        ("3c38c503c0376f9b4adcbe935d5f4b890391741c764f61b03cd4d0d42deae002", 256'u16),
+        ("3a54af3e9fa162bc8623cdf3e5d9b70bf30ade1d54cc3abea8659aba6cff471f", 256'u16),
+        ("6799a02ea1999aefdcbcc4d3ff9544478be7365a328d0d0f37c26bd95ade0cda", 256'u16),
+        ("e24a7bc9051058f918646b0f6e3d16884b2a55a15553b89bab910d55ebc36116", 256'u16)
       ]
 
     let targetId = toNodeId(PublicKey.fromHex(targetKey)[])