From 81fde1a80598cf375ccfd7f555f98c3614ae20db Mon Sep 17 00:00:00 2001 From: Neil Alexander Date: Sun, 22 Jul 2018 18:16:03 +0100 Subject: [PATCH] Use flow label instead of TCP/UDP/SCTP source/destination ports --- src/yggdrasil/session.go | 34 ++++++++++++---------------------- 1 file changed, 12 insertions(+), 22 deletions(-) diff --git a/src/yggdrasil/session.go b/src/yggdrasil/session.go index c605333..34da823 100644 --- a/src/yggdrasil/session.go +++ b/src/yggdrasil/session.go @@ -429,30 +429,20 @@ func (sinfo *sessionInfo) doSend(bs []byte) { // Specifically, we append a 0, and then arbitrary data // The 0 ensures that the destination node switch forwards to the self peer (router) // The rest is ignored, but it's still part as the coords, so it affects switch queues - // This helps separate traffic streams (protocol + source + dest port) are queued independently + // This helps separate traffic streams (coords, flowlabel) to be queued independently var coords []byte - addUint64 := func(bs []byte) { - // Converts bytes to a uint64 - // Converts that back to variable length bytes - // Appends it to coords - var u uint64 - for _, b := range bs { - u <<= 8 - u |= uint64(b) - } - coords = append(coords, wire_encode_uint64(u)...) - } coords = append(coords, sinfo.coords...) // Start with the real coords - coords = append(coords, 0) // Add an explicit 0 for the destination's self peer - addUint64(bs[6:7]) // Byte 6, next header type (e.g. TCP vs UDP) - // Is the next header TCP, UDP, SCTP for finding source port? - // 0x06 (6) = TCP, 0x11 (17) = UDP, 0x84 (132) = SCTP - // TODO: Perhaps improve this for other protocols - // TODO: Consider that the Next Header could be an IPv6 Extension Header instead - if bs[6:7][0] == 0x06 || bs[6:7][0] == 0x11 || bs[6:7][0] == 0x84 { - if len(bs) > 44 { - addUint64(bs[40:42]) // Bytes 40-41, source port for TCP/UDP/SCTP - addUint64(bs[42:44]) // Bytes 42-43, destination port for TCP/UDP/SCTP + flowlabel := int(bs[1:2][0]&0x0f)<<16 | int(bs[2:3][0])<<8 | int(bs[3:4][0]) + if flowlabel > 0 { + coords = append(coords, 0) // Add an explicit 0 for the destination's self peer + if flowlabel>>16 > 0 { + coords = append(coords, byte(flowlabel>>16)) + } + if flowlabel>>8 > 0 { + coords = append(coords, byte(flowlabel>>8)) + } + if flowlabel>>0 > 0 { + coords = append(coords, byte(flowlabel>>0)) } } payload, nonce := boxSeal(&sinfo.sharedSesKey, bs, &sinfo.myNonce)