feat: Adds IPv6 disabling feature (#803)

* Allow disabling IPv6

Simply ignores any IPv6 addresses in the lease and doesn't offer them to the RPC
Also fixed display issue for IPv6 link local address.
Fixes https://github.com/orgs/jetkvm/projects/7/views/1?pane=issue&itemId=122761546&issue=jetkvm%7Ckvm%7C685

* Don't listen on disabled addresses in mDNS or web server.

* We have to set the IPv4 and IPv6 modes on the server.

internal/network/config.go

@@ -56,13 +56,12 @@ type NetworkConfig struct {
 }
 
 func (c *NetworkConfig) GetMDNSMode() *mdns.MDNSListenOptions {
-	mode := c.MDNSMode.String
 	listenOptions := &mdns.MDNSListenOptions{
-		IPv4: true,
-		IPv6: true,
+		IPv4: c.IPv4Mode.String != "disabled",
+		IPv6: c.IPv6Mode.String != "disabled",
 	}
 
-	switch mode {
+	switch c.MDNSMode.String {
 	case "ipv4_only":
 		listenOptions.IPv6 = false
 	case "ipv6_only":

internal/network/netif.go

@@ -239,6 +239,10 @@ func (s *NetworkInterfaceState) update() (DhcpTargetState, error) {
 			ipv4Addresses = append(ipv4Addresses, addr.IP)
 			ipv4AddressesString = append(ipv4AddressesString, addr.IPNet.String())
 		} else if addr.IP.To16() != nil {
+			if s.config.IPv6Mode.String == "disabled" {
+				continue
+			}
+
 			scopedLogger := s.l.With().Str("ipv6", addr.IP.String()).Logger()
 			// check if it's a link local address
 			if addr.IP.IsLinkLocalUnicast() {
@@ -287,35 +291,37 @@ func (s *NetworkInterfaceState) update() (DhcpTargetState, error) {
 	}
 	s.ipv4Addresses = ipv4AddressesString
 
-	if ipv6LinkLocal != nil {
-		if s.ipv6LinkLocal == nil || s.ipv6LinkLocal.String() != ipv6LinkLocal.String() {
-			scopedLogger := s.l.With().Str("ipv6", ipv6LinkLocal.String()).Logger()
-			if s.ipv6LinkLocal != nil {
-				scopedLogger.Info().
-					Str("old_ipv6", s.ipv6LinkLocal.String()).
-					Msg("IPv6 link local address changed")
-			} else {
-				scopedLogger.Info().Msg("IPv6 link local address found")
+	if s.config.IPv6Mode.String != "disabled" {
+		if ipv6LinkLocal != nil {
+			if s.ipv6LinkLocal == nil || s.ipv6LinkLocal.String() != ipv6LinkLocal.String() {
+				scopedLogger := s.l.With().Str("ipv6", ipv6LinkLocal.String()).Logger()
+				if s.ipv6LinkLocal != nil {
+					scopedLogger.Info().
+						Str("old_ipv6", s.ipv6LinkLocal.String()).
+						Msg("IPv6 link local address changed")
+				} else {
+					scopedLogger.Info().Msg("IPv6 link local address found")
+				}
+				s.ipv6LinkLocal = ipv6LinkLocal
+				changed = true
 			}
-			s.ipv6LinkLocal = ipv6LinkLocal
-			changed = true
 		}
-	}
-	s.ipv6Addresses = ipv6Addresses
+		s.ipv6Addresses = ipv6Addresses
 
-	if len(ipv6Addresses) > 0 {
-		// compare the addresses to see if there's a change
-		if s.ipv6Addr == nil || s.ipv6Addr.String() != ipv6Addresses[0].Address.String() {
-			scopedLogger := s.l.With().Str("ipv6", ipv6Addresses[0].Address.String()).Logger()
-			if s.ipv6Addr != nil {
-				scopedLogger.Info().
-					Str("old_ipv6", s.ipv6Addr.String()).
-					Msg("IPv6 address changed")
-			} else {
-				scopedLogger.Info().Msg("IPv6 address found")
+		if len(ipv6Addresses) > 0 {
+			// compare the addresses to see if there's a change
+			if s.ipv6Addr == nil || s.ipv6Addr.String() != ipv6Addresses[0].Address.String() {
+				scopedLogger := s.l.With().Str("ipv6", ipv6Addresses[0].Address.String()).Logger()
+				if s.ipv6Addr != nil {
+					scopedLogger.Info().
+						Str("old_ipv6", s.ipv6Addr.String()).
+						Msg("IPv6 address changed")
+				} else {
+					scopedLogger.Info().Msg("IPv6 address found")
+				}
+				s.ipv6Addr = &ipv6Addresses[0].Address
+				changed = true
 			}
-			s.ipv6Addr = &ipv6Addresses[0].Address
-			changed = true
 		}
 	}
 

internal/network/rpc.go

@@ -65,7 +65,7 @@ func (s *NetworkInterfaceState) IPv6LinkLocalAddress() string {
 func (s *NetworkInterfaceState) RpcGetNetworkState() RpcNetworkState {
 	ipv6Addresses := make([]RpcIPv6Address, 0)
 
-	if s.ipv6Addresses != nil {
+	if s.ipv6Addresses != nil && s.config.IPv6Mode.String != "disabled" {
 		for _, addr := range s.ipv6Addresses {
 			ipv6Addresses = append(ipv6Addresses, RpcIPv6Address{
 				Address:           addr.Prefix.String(),

mdns.go

@@ -13,10 +13,7 @@ func initMdns() error {
 			networkState.GetHostname(),
 			networkState.GetFQDN(),
 		},
-		ListenOptions: &mdns.MDNSListenOptions{
-			IPv4: true,
-			IPv6: true,
-		},
+		ListenOptions: config.NetworkConfig.GetMDNSMode(),
 	})
 	if err != nil {
 		return err

ui/src/components/Ipv6NetworkCard.tsx

@@ -17,7 +17,7 @@ export default function Ipv6NetworkCard({
           </h3>
 
           <div className="grid grid-cols-2 gap-x-6 gap-y-2">
-            {networkState?.dhcp_lease?.ip && (
+            {networkState?.ipv6_link_local && (
               <div className="flex flex-col justify-between">
                 <span className="text-sm text-slate-600 dark:text-slate-400">
                   Link-local

ui/src/routes/devices.$id.settings.network.tsx

@@ -166,11 +166,11 @@ export default function SettingsNetworkRoute() {
   }, [getNetworkState, getNetworkSettings]);
 
   const handleIpv4ModeChange = (value: IPv4Mode | string) => {
-    setNetworkSettings({ ...networkSettings, ipv4_mode: value as IPv4Mode });
+    setNetworkSettingsRemote({ ...networkSettings, ipv4_mode: value as IPv4Mode });
   };
 
   const handleIpv6ModeChange = (value: IPv6Mode | string) => {
-    setNetworkSettings({ ...networkSettings, ipv6_mode: value as IPv6Mode });
+    setNetworkSettingsRemote({ ...networkSettings, ipv6_mode: value as IPv6Mode });
   };
 
   const handleLldpModeChange = (value: LLDPMode | string) => {
@@ -419,7 +419,7 @@ export default function SettingsNetworkRoute() {
               value={networkSettings.ipv6_mode}
               onChange={e => handleIpv6ModeChange(e.target.value)}
               options={filterUnknown([
-                // { value: "disabled", label: "Disabled" },
+                { value: "disabled", label: "Disabled" },
                 { value: "slaac", label: "SLAAC" },
                 // { value: "dhcpv6", label: "DHCPv6" },
                 // { value: "slaac_and_dhcpv6", label: "SLAAC and DHCPv6" },

web.go

@@ -562,14 +562,31 @@ func RunWebServer() {
 	r := setupRouter()
 
 	// Determine the binding address based on the config
-	bindAddress := ":80" // Default to all interfaces
+	var bindAddress string
+	listenPort := 80 // default port
+	useIPv4 := config.NetworkConfig.IPv4Mode.String != "disabled"
+	useIPv6 := config.NetworkConfig.IPv6Mode.String != "disabled"
+
 	if config.LocalLoopbackOnly {
-		bindAddress = "localhost:80" // Loopback only (both IPv4 and IPv6)
+		if useIPv4 && useIPv6 {
+			bindAddress = fmt.Sprintf("localhost:%d", listenPort)
+		} else if useIPv4 {
+			bindAddress = fmt.Sprintf("127.0.0.1:%d", listenPort)
+		} else if useIPv6 {
+			bindAddress = fmt.Sprintf("[::1]:%d", listenPort)
+		}
+	} else {
+		if useIPv4 && useIPv6 {
+			bindAddress = fmt.Sprintf(":%d", listenPort)
+		} else if useIPv4 {
+			bindAddress = fmt.Sprintf("0.0.0.0:%d", listenPort)
+		} else if useIPv6 {
+			bindAddress = fmt.Sprintf("[::]:%d", listenPort)
+		}
 	}
 
 	logger.Info().Str("bindAddress", bindAddress).Bool("loopbackOnly", config.LocalLoopbackOnly).Msg("Starting web server")
-	err := r.Run(bindAddress)
-	if err != nil {
+	if err := r.Run(bindAddress); err != nil {
 		panic(err)
 	}
 }