chore: wireguard dns can work with domain-based server

adapter/outbound/base.go

@@ -93,6 +93,11 @@ func (b *Base) SupportTFO() bool {
 	return b.tfo
 }
 
+// IsL3Protocol implements C.ProxyAdapter
+func (b *Base) IsL3Protocol(metadata *C.Metadata) bool {
+	return false
+}
+
 // MarshalJSON implements C.ProxyAdapter
 func (b *Base) MarshalJSON() ([]byte, error) {
 	return json.Marshal(map[string]string{

adapter/outbound/wireguard.go

@@ -401,3 +401,8 @@ func (w *WireGuard) ListenPacketContext(ctx context.Context, metadata *C.Metadat
 	}
 	return newPacketConn(CN.NewRefPacketConn(pc, w), w), nil
 }
+
+// IsL3Protocol implements C.ProxyAdapter
+func (w *WireGuard) IsL3Protocol(metadata *C.Metadata) bool {
+	return true
+}

adapter/outboundgroup/fallback.go

@@ -70,6 +70,11 @@ func (f *Fallback) SupportUDP() bool {
 	return proxy.SupportUDP()
 }
 
+// IsL3Protocol implements C.ProxyAdapter
+func (f *Fallback) IsL3Protocol(metadata *C.Metadata) bool {
+	return f.findAliveProxy(false).IsL3Protocol(metadata)
+}
+
 // MarshalJSON implements C.ProxyAdapter
 func (f *Fallback) MarshalJSON() ([]byte, error) {
 	all := []string{}

adapter/outboundgroup/loadbalance.go

@@ -124,6 +124,11 @@ func (lb *LoadBalance) SupportUDP() bool {
 	return !lb.disableUDP
 }
 
+// IsL3Protocol implements C.ProxyAdapter
+func (lb *LoadBalance) IsL3Protocol(metadata *C.Metadata) bool {
+	return lb.Unwrap(metadata, false).IsL3Protocol(metadata)
+}
+
 func strategyRoundRobin() strategyFn {
 	idx := 0
 	idxMutex := sync.Mutex{}

adapter/outboundgroup/selector.go

@@ -44,6 +44,11 @@ func (s *Selector) SupportUDP() bool {
 	return s.selectedProxy(false).SupportUDP()
 }
 
+// IsL3Protocol implements C.ProxyAdapter
+func (s *Selector) IsL3Protocol(metadata *C.Metadata) bool {
+	return s.selectedProxy(false).IsL3Protocol(metadata)
+}
+
 // MarshalJSON implements C.ProxyAdapter
 func (s *Selector) MarshalJSON() ([]byte, error) {
 	all := []string{}

adapter/outboundgroup/urltest.go

@@ -147,6 +147,11 @@ func (u *URLTest) SupportUDP() bool {
 	return u.fast(false).SupportUDP()
 }
 
+// IsL3Protocol implements C.ProxyAdapter
+func (u *URLTest) IsL3Protocol(metadata *C.Metadata) bool {
+	return u.fast(false).IsL3Protocol(metadata)
+}
+
 // MarshalJSON implements C.ProxyAdapter
 func (u *URLTest) MarshalJSON() ([]byte, error) {
 	all := []string{}

component/resolver/resolver.go

@@ -48,6 +48,7 @@ type Resolver interface {
 	ResolveIPv4(ctx context.Context, host string) (ip netip.Addr, err error)
 	ResolveIPv6(ctx context.Context, host string) (ip netip.Addr, err error)
 	ExchangeContext(ctx context.Context, m *dns.Msg) (msg *dns.Msg, err error)
+	Invalid() bool
 }
 
 // LookupIPv4WithResolver same as LookupIPv4, but with a resolver
@@ -68,7 +69,7 @@ func LookupIPv4WithResolver(ctx context.Context, host string, r Resolver) ([]net
 		return []netip.Addr{}, ErrIPVersion
 	}
 
-	if r != nil {
+	if r != nil && r.Invalid() {
 		return r.LookupIPv4(ctx, host)
 	}
 
@@ -124,7 +125,7 @@ func LookupIPv6WithResolver(ctx context.Context, host string, r Resolver) ([]net
 		return nil, ErrIPVersion
 	}
 
-	if r != nil {
+	if r != nil && r.Invalid() {
 		return r.LookupIPv6(ctx, host)
 	}
 
@@ -164,7 +165,7 @@ func LookupIPWithResolver(ctx context.Context, host string, r Resolver) ([]netip
 		return node.IPs, nil
 	}
 
-	if r != nil {
+	if r != nil && r.Invalid() {
 		if DisableIPv6 {
 			return r.LookupIPv4(ctx, host)
 		}

constant/adapters.go

@@ -124,6 +124,9 @@ type ProxyAdapter interface {
 	DialContextWithDialer(ctx context.Context, dialer Dialer, metadata *Metadata) (Conn, error)
 	ListenPacketWithDialer(ctx context.Context, dialer Dialer, metadata *Metadata) (PacketConn, error)
 
+	// IsL3Protocol return ProxyAdapter working in L3 (tell dns module not pass the domain to avoid loopback)
+	IsL3Protocol(metadata *Metadata) bool
+
 	// Unwrap extracts the proxy from a proxy-group. It returns nil when nothing to extract.
 	Unwrap(metadata *Metadata, touch bool) Proxy
 }

dns/resolver.go

@@ -412,8 +412,11 @@ func (r *Resolver) asyncExchange(ctx context.Context, client []dnsClient, msg *D
 	return ch
 }
 
-// HasProxyServer has proxy server dns client
-func (r *Resolver) HasProxyServer() bool {
+// Invalid return this resolver can or can't be used
+func (r *Resolver) Invalid() bool {
+	if r == nil {
+		return false
+	}
 	return len(r.main) > 0
 }
 

dns/util.go

@@ -170,6 +170,14 @@ func getDialHandler(r *Resolver, proxyAdapter C.ProxyAdapter, proxyName string,
 					Host:    host,
 					DstPort: port,
 				}
+				if proxyAdapter.IsL3Protocol(metadata) {
+					dstIP, err := resolver.ResolveIPWithResolver(ctx, host, r)
+					if err != nil {
+						return nil, err
+					}
+					metadata.Host = ""
+					metadata.DstIP = dstIP
+				}
 				if proxyAdapter != nil {
 					return proxyAdapter.DialContext(ctx, metadata, opts...)
 				}

hub/executor/executor.go

@@ -239,7 +239,7 @@ func updateDNS(c *config.DNS, ruleProvider map[string]provider.RuleProvider, gen
 	resolver.DefaultHostMapper = m
 	resolver.DefaultLocalServer = dns.NewLocalServer(r, m)
 
-	if pr.HasProxyServer() {
+	if pr.Invalid() {
 		resolver.ProxyServerHostResolver = pr
 	}