IPv6 handling updates

- Try connecting via IPv4 addresses first
- Ignore IPv6 link local addresses

hub/hub_connections.go

@@ -6,7 +6,9 @@ import (
 	"errors"
 	"fmt"
 	"math/rand"
+	"net"
 	"net/http"
+	"slices"
 	"strconv"
 	"time"
 
@@ -353,6 +355,17 @@ func (h *Hub) initateConnection(remoteService *api.ServiceDetails, entry *api.Md
 		}
 	}
 
+	// try IPv4 addresses before IPv6 addresses
+	slices.SortFunc(entry.Addresses, func(a, b net.IP) int {
+		if a.To4() != nil && b.To4() == nil {
+			return -1
+		}
+		if a.To4() == nil && b.To4() != nil {
+			return 1
+		}
+		return 0
+	})
+
 	// try connecting via the provided IP addresses
 	for _, address := range entry.Addresses {
 		logging.Log().Debug("trying to connect to", remoteService.SKI(), "at", address)

mdns/mdns.go

@@ -345,6 +345,16 @@ func (m *MdnsManager) processMdnsEntry(elements map[string]string, name, host st
 		return
 	}
 
+	// remove IPv6 local link addresses
+	var newAddresses []net.IP
+	for _, address := range addresses {
+		if address.To4() == nil && address.IsLinkLocalUnicast() {
+			continue
+		}
+		newAddresses = append(newAddresses, address)
+	}
+	addresses = newAddresses
+
 	var deviceType, model, brand string
 
 	if _, ok := elements["brand"]; ok {

mdns/mdns_test.go

@@ -218,7 +218,7 @@ func (s *MdnsSuite) Test_ProcessMdnsEntry() {
 	s.sut.processMdnsEntry(elements, name, host, ips, port, false)
 	assert.Equal(s.T(), 1, len(s.sut.mdnsEntries()))
 
-	ips = []net.IP{[]byte("127.0.0.1")}
+	ips = []net.IP{[]byte("127.0.0.1"), []byte{0xfe, 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}
 	s.sut.processMdnsEntry(elements, name, host, ips, port, false)
 	assert.Equal(s.T(), 1, len(s.sut.mdnsEntries()))