diff options
| -rw-r--r-- | wgengine/magicsock/magicsock.go | 59 |
1 files changed, 41 insertions, 18 deletions
diff --git a/wgengine/magicsock/magicsock.go b/wgengine/magicsock/magicsock.go index fd0b091d1..3713c5273 100644 --- a/wgengine/magicsock/magicsock.go +++ b/wgengine/magicsock/magicsock.go @@ -111,7 +111,7 @@ var derpMagicIP = net.ParseIP(DerpMagicIP).To4() // activeDerp contains fields for an active DERP connection. type activeDerp struct { - c *derphttp.Client + c *derphttp.Client // Conn.derpMu must be held cancel context.CancelFunc writeCh chan<- derpWriteRequest lastWrite *time.Time @@ -412,7 +412,9 @@ func (c *Conn) setNearestDERP(derpNum int) (wantDERP bool) { c.myDerp = derpNum c.logf("home DERP server is now %v, %v", derpNum, c.derps.ServerByID(derpNum)) for i, ad := range c.activeDerp { - go ad.c.NotePreferred(i == c.myDerp) + if ad.c != nil { + go ad.c.NotePreferred(i == c.myDerp) + } } if derpNum != 0 && derpNum != c.myDerp { // On change, start connecting to it: @@ -707,32 +709,51 @@ func (c *Conn) derpWriteChanOfAddr(addr *net.UDPAddr) chan<- derpWriteRequest { return nil } - // TODO(bradfitz): don't hold derpMu here. It's slow. Release first and use singleflight to dial+re-lock to add. - dc, err := derphttp.NewClient(c.privateKey, "https://"+derpSrv.HostHTTPS+"/derp", c.logf) - if err != nil { - c.logf("derphttp.NewClient: port %d, host %q invalid? err: %v", addr.Port, derpSrv.HostHTTPS, err) - return nil - } - dc.NotePreferred(c.myDerp == addr.Port) - dc.DNSCache = dnscache.Get() - dc.TLSConfig = c.derpTLSConfig - ctx, cancel := context.WithCancel(context.Background()) ch := make(chan derpWriteRequest, bufferedDerpWritesBeforeDrop) - - ad.c = dc ad.writeCh = ch ad.cancel = cancel ad.lastWrite = new(time.Time) c.activeDerp[addr.Port] = ad - - go c.runDerpReader(ctx, addr, dc) - go c.runDerpWriter(ctx, addr, dc, ch) + go c.dialDerp(ctx, addr, &ad, ch, derpSrv) } *ad.lastWrite = time.Now() return ad.writeCh } +func (c *Conn) dialDerp(ctx context.Context, addr *net.UDPAddr, ad *activeDerp, ch chan derpWriteRequest, derpSrv *derpmap.Server) { + dc, err := derphttp.NewClient(c.privateKey, "https://"+derpSrv.HostHTTPS+"/derp", c.logf) + if err != nil { + c.logf("derphttp.NewClient: port %d, host %q invalid? err: %v", addr.Port, derpSrv.HostHTTPS, err) + + c.derpMu.Lock() + if ctx.Err() == nil { + ad.cancel() + delete(c.activeDerp, addr.Port) + } + c.derpMu.Unlock() + + return + } + dc.NotePreferred(c.myDerp == addr.Port) + dc.DNSCache = dnscache.Get() + dc.TLSConfig = c.derpTLSConfig + + c.derpMu.Lock() + if ctx.Err() != nil { + // Some other dialDerp beat us to the punch. + c.derpMu.Unlock() + dc.Close() + return + } + ad.c = dc + c.activeDerp[addr.Port] = *ad + c.derpMu.Unlock() + + go c.runDerpReader(ctx, addr, dc) + go c.runDerpWriter(ctx, addr, dc, ch) +} + // derpReadResult is the type sent by runDerpClient to ReceiveIPv4 // when a DERP packet is available. // @@ -1035,7 +1056,9 @@ func (c *Conn) closeAllDerpLocked() { func (c *Conn) closeDerpLocked(node int) { if ad, ok := c.activeDerp[node]; ok { c.logf("closing connection to derp%v", node) - go ad.c.Close() + if ad.c != nil { + go ad.c.Close() + } ad.cancel() delete(c.activeDerp, node) } |