mirror of
https://github.com/cwinfo/yggdrasil-go.git
synced 2024-11-10 07:30:27 +00:00
Clean up the flow a bit (partly because I am allergic to huge compounded if statements)
This commit is contained in:
parent
68a482ed92
commit
ebb4ec7c33
@ -423,40 +423,37 @@ func (sinfo *sessionInfo) doWorker() {
|
||||
func (sinfo *sessionInfo) doSend(bs []byte) {
|
||||
defer util_putBytes(bs)
|
||||
if !sinfo.init {
|
||||
// To prevent using empty session keys
|
||||
return
|
||||
} // To prevent using empty session keys
|
||||
|
||||
}
|
||||
coords := sinfo.coords
|
||||
// Read IPv6 flowlabel field (20 bits).
|
||||
// Assumes packet at least contains IPv6 header.
|
||||
flowkey := uint64(bs[1]&0x0f)<<16 | uint64(bs[2])<<8 | uint64(bs[3])
|
||||
if flowkey == 0 /* not specified */ &&
|
||||
len(bs) >= 48 /* min UDP len, others are bigger */ &&
|
||||
(bs[6] == 0x06 || bs[6] == 0x11 || bs[6] == 0x84) /* TCP UDP SCTP */ {
|
||||
// if flowlabel was unspecified (0), try to use known protocols' ports
|
||||
// protokey: proto | sport | dport
|
||||
flowkey = uint64(bs[6])<<32 /* proto */ |
|
||||
uint64(bs[40])<<24 | uint64(bs[41])<<16 /* sport */ |
|
||||
uint64(bs[42])<<8 | uint64(bs[43]) /* dport */
|
||||
// Check if the flowlabel was specified
|
||||
if flowkey == 0 {
|
||||
// Does the packet meet the minimum UDP packet size? (others are bigger)
|
||||
if len(bs) >= 48 {
|
||||
// Is the protocol TCP, UDP, SCTP?
|
||||
if bs[6] == 0x06 || bs[6] == 0x11 || bs[6] == 0x84 {
|
||||
// if flowlabel was unspecified (0), try to use known protocols' ports
|
||||
// protokey: proto | sport | dport
|
||||
flowkey = uint64(bs[6])<<32 /* proto */ |
|
||||
uint64(bs[40])<<24 | uint64(bs[41])<<16 /* sport */ |
|
||||
uint64(bs[42])<<8 | uint64(bs[43]) /* dport */
|
||||
}
|
||||
}
|
||||
}
|
||||
var coords []byte
|
||||
// If we have a flowkey, either through the IPv6 flowlabel field or through
|
||||
// known TCP/UDP/SCTP proto-sport-dport triplet, then append it to the coords.
|
||||
// Appending extra coords after a 0 ensures that we still target the local router
|
||||
// but lets us send extra data (which is otherwise ignored) to help separate
|
||||
// traffic streams into independent queues
|
||||
if flowkey != 0 {
|
||||
// Now we append something to the coords
|
||||
// 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 (coords, flowlabel) to be queued independently
|
||||
|
||||
// TODO could we avoid allocations there and put this work into wire_trafficPacket.encode()?
|
||||
coords = append(coords, sinfo.coords...) // Start with the real coords
|
||||
coords = append(coords, 0) // Then target the local switchport
|
||||
coords = append(coords, 0) // First target the local switchport
|
||||
coords = wire_put_uint64(flowkey, coords) // Then variable-length encoded flowkey
|
||||
} else {
|
||||
// flowlabel was unspecified (0) and protocol unrecognised.
|
||||
// To save bytes, we're not including it, therefore we won't need self-port override either.
|
||||
// So just use sinfo.coords directly to avoid golang GC allocations.
|
||||
// Recent enough Linux and BSDs support flowlabels (auto_flowlabel) out of the box so this will be rare.
|
||||
coords = sinfo.coords
|
||||
}
|
||||
// Prepare the payload
|
||||
payload, nonce := boxSeal(&sinfo.sharedSesKey, bs, &sinfo.myNonce)
|
||||
defer util_putBytes(payload)
|
||||
p := wire_trafficPacket{
|
||||
|
Loading…
Reference in New Issue
Block a user