Try to exchange MTUs when creating sessions

This commit is contained in:
Neil Alexander 2018-02-11 23:09:05 +00:00
parent 38567fffef
commit 536974f20c
2 changed files with 20 additions and 0 deletions

View File

@ -223,6 +223,7 @@ func (a *admin) getData_getSessions() []admin_nodeInfo {
info := admin_nodeInfo{ info := admin_nodeInfo{
{"IP", net.IP(sinfo.theirAddr[:]).String()}, {"IP", net.IP(sinfo.theirAddr[:]).String()},
{"coords", fmt.Sprint(sinfo.coords)}, {"coords", fmt.Sprint(sinfo.coords)},
{"MTU", fmt.Sprint(sinfo.getMTU())},
} }
infos = append(infos, info) infos = append(infos, info)
} }

View File

@ -5,6 +5,7 @@ package yggdrasil
// The session information consists of crypto keys and coords // The session information consists of crypto keys and coords
import "time" import "time"
import "net"
type sessionInfo struct { type sessionInfo struct {
core *Core core *Core
@ -19,6 +20,8 @@ type sessionInfo struct {
myHandle handle myHandle handle
theirNonce boxNonce theirNonce boxNonce
myNonce boxNonce myNonce boxNonce
theirMTU uint16
myMTU uint16
time time.Time // Time we last received a packet time time.Time // Time we last received a packet
coords []byte // coords of destination coords []byte // coords of destination
packet []byte // a buffered packet, sent immediately on ping/pong packet []byte // a buffered packet, sent immediately on ping/pong
@ -36,6 +39,7 @@ type sessionPing struct {
coords []byte coords []byte
tstamp int64 // unix time, but the only real requirement is that it increases tstamp int64 // unix time, but the only real requirement is that it increases
isPong bool isPong bool
mtu uint16
} }
// Returns true if the session was updated, false otherwise // Returns true if the session was updated, false otherwise
@ -56,6 +60,10 @@ func (s *sessionInfo) update(p *sessionPing) bool {
s.theirNonce = boxNonce{} s.theirNonce = boxNonce{}
s.nonceMask = 0 s.nonceMask = 0
} }
s.core.log.Printf("Received MTU %d from %s", p.mtu, net.IP(s.theirAddr[:]).String())
if p.mtu >= 1280 {
s.theirMTU = p.mtu
}
s.coords = append([]byte{}, p.coords...) s.coords = append([]byte{}, p.coords...)
s.time = time.Now() s.time = time.Now()
s.tstamp = p.tstamp s.tstamp = p.tstamp
@ -144,6 +152,8 @@ func (ss *sessions) createSession(theirPermKey *boxPubKey) *sessionInfo {
sinfo.mySesPub = *pub sinfo.mySesPub = *pub
sinfo.mySesPriv = *priv sinfo.mySesPriv = *priv
sinfo.myNonce = *newBoxNonce() sinfo.myNonce = *newBoxNonce()
sinfo.theirMTU = 1280
sinfo.myMTU = uint16(ss.core.tun.mtu)
higher := false higher := false
for idx := range ss.core.boxPub { for idx := range ss.core.boxPub {
if ss.core.boxPub[idx] > sinfo.theirPermPub[idx] { if ss.core.boxPub[idx] > sinfo.theirPermPub[idx] {
@ -195,12 +205,14 @@ func (sinfo *sessionInfo) close() {
func (ss *sessions) getPing(sinfo *sessionInfo) sessionPing { func (ss *sessions) getPing(sinfo *sessionInfo) sessionPing {
loc := ss.core.switchTable.getLocator() loc := ss.core.switchTable.getLocator()
coords := loc.getCoords() coords := loc.getCoords()
sinfo.core.log.Printf("Sending MTU %d to %s", sinfo.myMTU, net.IP(sinfo.theirAddr[:]).String())
ref := sessionPing{ ref := sessionPing{
sendPermPub: ss.core.boxPub, sendPermPub: ss.core.boxPub,
handle: sinfo.myHandle, handle: sinfo.myHandle,
sendSesPub: sinfo.mySesPub, sendSesPub: sinfo.mySesPub,
tstamp: time.Now().Unix(), tstamp: time.Now().Unix(),
coords: coords, coords: coords,
mtu: sinfo.myMTU,
} }
sinfo.myNonce.update() sinfo.myNonce.update()
return ref return ref
@ -289,6 +301,13 @@ func (n *boxNonce) minus(m *boxNonce) int64 {
return diff return diff
} }
func (sinfo *sessionInfo) getMTU() uint16 {
if sinfo.theirMTU < sinfo.myMTU {
return sinfo.theirMTU
}
return sinfo.myMTU
}
func (sinfo *sessionInfo) nonceIsOK(theirNonce *boxNonce) bool { func (sinfo *sessionInfo) nonceIsOK(theirNonce *boxNonce) bool {
// The bitmask is to allow for some non-duplicate out-of-order packets // The bitmask is to allow for some non-duplicate out-of-order packets
diff := theirNonce.minus(&sinfo.theirNonce) diff := theirNonce.minus(&sinfo.theirNonce)