udpmux: announce on any addr not src

Author: ignoramous

intra/icmp.go

@@ -171,12 +171,7 @@ func (h *icmpHandler) Ping(source, target netip.AddrPort, msg []byte) (echoed bo
 	}
 
 	dst := oneRealIp(realips, target)
-	anyaddr := "0.0.0.0:0"
-	proto := "udp4"
-	if target.Addr().Is6() {
-		proto = "udp6"
-		anyaddr = "[::]:0"
-	}
+	proto, anyaddr := anyaddrFor(dst)
 	// todo: use dialers.ListenICMP?
 	uc, err := px.Dialer().Probe(proto, anyaddr)
 	ucnil := uc == nil || core.IsNil(uc)
@@ -221,6 +216,16 @@ func extend(c core.MinConn, t time.Duration) {
 	}
 }
 
+func anyaddrFor(ipp netip.AddrPort) (proto, anyaddr string) {
+	anyaddr = "0.0.0.0:0"
+	proto = "udp4"
+	if ipp.Addr().Is6() {
+		proto = "udp6"
+		anyaddr = "[::]:0"
+	}
+	return
+}
+
 func logei(err error, msg string, args ...any) {
 	f := log.E
 	if err == nil {

intra/udpmux.go

@@ -473,15 +473,16 @@ func newMuxTable() *muxTable {
 	return &muxTable{t: make(map[netip.AddrPort]*muxer)}
 }
 
-func (e *muxTable) associate(id string, src netip.AddrPort, mk assocFn, vendor netstack.DemuxerFn) (*muxer, error) {
+func (e *muxTable) associate(id string, src netip.AddrPort, mk assocFn, v netstack.DemuxerFn) (*muxer, error) {
 	e.Lock()
 	defer e.Unlock()
 
+	proto, anyaddr := anyaddrFor(src)
 	if mxr, ok := e.t[src]; ok {
 		return mxr, nil
-	} else if pc, err := mk("udp", src.String()); err == nil {
+	} else if pc, err := mk(proto, anyaddr); err == nil {
 		log.I("udp: mux: %s new assoc for %s", id, src)
-		mxr = newMuxerLocked(id, pc, vendor, func() {
+		mxr = newMuxerLocked(id, pc, v, func() {
 			e.dissociate(id, src)
 		})
 		e.t[src] = mxr