feat: support ipv6 link-local address

p2p/discovery/mdns/mdns.go

@@ -86,10 +86,16 @@ func (s *mdnsService) Close() error {
 func (s *mdnsService) getIPs(addrs []ma.Multiaddr) ([]string, error) {
 	var ip4, ip6 string
 	for _, addr := range addrs {
-		first, _ := ma.SplitFirst(addr)
+		first, remaining := ma.SplitFirst(addr)
 		if first == nil {
 			continue
 		}
+		if first.Protocol().Code == ma.P_IP6ZONE {
+			first, _ = ma.SplitFirst(remaining)
+			if first == nil {
+				continue
+			}
+		}
 		if ip4 == "" && first.Protocol().Code == ma.P_IP4 {
 			ip4 = first.Value()
 		} else if ip6 == "" && first.Protocol().Code == ma.P_IP6 {

p2p/host/basic/basic_host.go

@@ -782,22 +782,27 @@ func (h *BasicHost) Addrs() []ma.Multiaddr {
 
 	// Copy addrs slice since we'll be modifying it.
 	addrsOld := addrs
-	addrs = make([]ma.Multiaddr, len(addrsOld))
-	copy(addrs, addrsOld)
+	addrs = make([]ma.Multiaddr, 0, len(addrsOld))
 
-	for i, addr := range addrs {
+	for _, addr := range addrsOld {
 		if ok, n := libp2pwebtransport.IsWebtransportMultiaddr(addr); ok && n == 0 {
 			t := s.TransportForListening(addr)
 			tpt, ok := t.(addCertHasher)
 			if !ok {
+				addrs = append(addrs, addr)
 				continue
 			}
 			addrWithCerthash, added := tpt.AddCertHashes(addr)
 			if !added {
+				addrs = append(addrs, addr)
 				log.Debug("Couldn't add certhashes to webtransport multiaddr because we aren't listening on webtransport")
 				continue
 			}
-			addrs[i] = addrWithCerthash
+			addrs = append(addrs, addrWithCerthash)
+		} else if manet.IsIP6LinkLocal(addr) {
+			continue
+		} else {
+			addrs = append(addrs, addr)
 		}
 	}
 	return addrs

p2p/net/reuseport/dialer.go

@@ -50,7 +50,7 @@ func (d *dialer) DialContext(ctx context.Context, network, addr string) (net.Con
 			return nil, err
 		}
 		ip := tcpAddr.IP
-		if !ip.IsLoopback() && !ip.IsGlobalUnicast() {
+		if !ip.IsLoopback() && !ip.IsGlobalUnicast() && !ip.IsLinkLocalUnicast() {
 			return nil, fmt.Errorf("undialable IP: %s", ip)
 		}
 

p2p/net/swarm/swarm_dial.go

@@ -489,8 +489,6 @@ func (s *Swarm) filterKnownUndialables(p peer.ID, addrs []ma.Multiaddr) (goodAdd
 			}
 			return true
 		},
-		// TODO: Consider allowing link-local addresses
-		func(addr ma.Multiaddr) bool { return !manet.IsIP6LinkLocal(addr) },
 		func(addr ma.Multiaddr) bool {
 			if s.gater != nil && !s.gater.InterceptAddrDial(p, addr) {
 				addrErrs = append(addrErrs, TransportError{Address: addr, Cause: ErrGaterDisallowedConnection})

p2p/transport/tcp/tcp.go

@@ -152,7 +152,10 @@ func NewTCPTransport(upgrader transport.Upgrader, rcmgr network.ResourceManager,
 	return tr, nil
 }
 
-var dialMatcher = mafmt.And(mafmt.IP, mafmt.Base(ma.P_TCP))
+var dialMatcher = mafmt.Or(
+	mafmt.And(mafmt.IP, mafmt.Base(ma.P_TCP)),
+	mafmt.And(mafmt.Base(ma.P_IP6ZONE), mafmt.IP, mafmt.Base(ma.P_TCP)),
+)
 
 // CanDial returns true if this transport believes it can dial the given
 // multiaddr.