diff options
| -rw-r--r-- | wgengine/userspace.go | 114 |
1 files changed, 76 insertions, 38 deletions
diff --git a/wgengine/userspace.go b/wgengine/userspace.go index c47fb0fa7..a19ca15e5 100644 --- a/wgengine/userspace.go +++ b/wgengine/userspace.go @@ -66,7 +66,7 @@ type userspaceEngine struct { statusCallback StatusCallback peerSequence []wgcfg.Key endpoints []string - pingers map[wgcfg.Key]context.CancelFunc // mu must be held to call CancelFunc + pingers map[wgcfg.Key]*pinger linkState *interfaces.State // Lock ordering: wgLock, then mu. @@ -128,7 +128,7 @@ func newUserspaceEngineAdvanced(logf logger.Logf, tundev *tstun.TUN, routerGen R reqCh: make(chan struct{}, 1), waitCh: make(chan struct{}), tundev: tundev, - pingers: make(map[wgcfg.Key]context.CancelFunc), + pingers: make(map[wgcfg.Key]*pinger), } e.linkState, _ = getLinkState() @@ -259,28 +259,29 @@ func newUserspaceEngineAdvanced(logf logger.Logf, tundev *tstun.TUN, routerGen R // // These generated packets are used to ensure we trigger the spray logic in // the magicsock package for NAT traversal. -func (e *userspaceEngine) pinger(peerKey wgcfg.Key, ips []wgcfg.IP) { - e.logf("generating initial ping traffic to %s (%v)", peerKey.ShortString(), ips) - var srcIP packet.IP +type pinger struct { + e *userspaceEngine + done chan struct{} // closed after shutdown (not the ctx.Done() chan) + cancel context.CancelFunc +} - e.wgLock.Lock() - if len(e.lastCfg.Addresses) > 0 { - srcIP = packet.NewIP(e.lastCfg.Addresses[0].IP.IP()) - } - e.wgLock.Unlock() +// close cleans up pinger and removes it from the userspaceEngine.pingers map. +// It cannot be called while p.e.mu is held. +func (p *pinger) close() { + p.cancel() + <-p.done +} - if srcIP == 0 { - e.logf("generating initial ping traffic: no source IP") - return - } +func (p *pinger) run(ctx context.Context, peerKey wgcfg.Key, ips []wgcfg.IP, srcIP packet.IP) { + defer func() { + p.e.mu.Lock() + if p.e.pingers[peerKey] == p { + delete(p.e.pingers, peerKey) + } + p.e.mu.Unlock() - e.mu.Lock() - if cancel := e.pingers[peerKey]; cancel != nil { - cancel() - } - ctx, cancel := context.WithCancel(context.Background()) - e.pingers[peerKey] = cancel - e.mu.Unlock() + close(p.done) + }() // sendFreq is slightly longer than sprayFreq in magicsock to ensure // that if these ping packets are the only source of early packets @@ -296,19 +297,6 @@ func (e *userspaceEngine) pinger(peerKey wgcfg.Key, ips []wgcfg.IP) { payload := []byte("magicsock_spray") // no meaning - defer func() { - e.mu.Lock() - defer e.mu.Unlock() - select { - case <-ctx.Done(): - return - default: - } - // If the pinger context is not done, then the - // CancelFunc is still in the pingers map. - delete(e.pingers, peerKey) - }() - ipid := uint16(1) t := time.NewTicker(sendFreq) defer t.Stop() @@ -323,10 +311,52 @@ func (e *userspaceEngine) pinger(peerKey wgcfg.Key, ips []wgcfg.IP) { } for _, dstIP := range dstIPs { b := packet.GenICMP(srcIP, dstIP, ipid, packet.ICMPEchoRequest, 0, payload) - e.tundev.InjectOutbound(b) + p.e.tundev.InjectOutbound(b) } ipid++ } + +} + +// pinger sends ping packets for a few seconds. +// +// These generated packets are used to ensure we trigger the spray logic in +// the magicsock package for NAT traversal. +func (e *userspaceEngine) pinger(peerKey wgcfg.Key, ips []wgcfg.IP) { + e.logf("generating initial ping traffic to %s (%v)", peerKey.ShortString(), ips) + var srcIP packet.IP + + e.wgLock.Lock() + if len(e.lastCfg.Addresses) > 0 { + srcIP = packet.NewIP(e.lastCfg.Addresses[0].IP.IP()) + } + e.wgLock.Unlock() + + if srcIP == 0 { + e.logf("generating initial ping traffic: no source IP") + return + } + + ctx, cancel := context.WithCancel(context.Background()) + p := &pinger{ + e: e, + done: make(chan struct{}), + cancel: cancel, + } + + e.mu.Lock() + if e.closing { + e.mu.Unlock() + return + } + oldPinger := e.pingers[peerKey] + e.pingers[peerKey] = p + e.mu.Unlock() + + if oldPinger != nil { + oldPinger.close() + } + p.run(ctx, peerKey, ips, srcIP) } func configSignature(cfg *wgcfg.Config, routerCfg *router.Config) (string, error) { @@ -565,15 +595,16 @@ func (e *userspaceEngine) RequestStatus() { } func (e *userspaceEngine) Close() { + var pingers []*pinger + e.mu.Lock() if e.closing { e.mu.Unlock() return } e.closing = true - for key, cancel := range e.pingers { - delete(e.pingers, key) - cancel() + for _, pinger := range e.pingers { + pingers = append(pingers, pinger) } e.mu.Unlock() @@ -583,6 +614,13 @@ func (e *userspaceEngine) Close() { e.linkMon.Close() e.router.Close() e.magicConn.Close() + + // Shut down pingers after tundev is closed (by e.wgdev.Close) so the + // synchronous close does not get stuck on InjectOutbound. + for _, pinger := range pingers { + pinger.close() + } + close(e.waitCh) } |