refactor: 优化UDP远程目标获取

adapter/outbound/base.go

@@ -129,6 +129,11 @@ func NewBase(opt BaseOption) *Base {
 type conn struct {
 	net.Conn
 	chain             C.Chain
+	lastAdapterRemote string
+}
+
+func (c *conn) RemoteDestination() string {
+	return c.lastAdapterRemote
 }
 
 // Chains implements C.Connection
@@ -142,12 +147,17 @@ func (c *conn) AppendToChains(a C.ProxyAdapter) {
 }
 
 func NewConn(c net.Conn, a C.ProxyAdapter) C.Conn {
-	return &conn{c, []string{a.Name()}}
+	return &conn{c, []string{a.Name()}, a.Addr()}
 }
 
 type packetConn struct {
 	net.PacketConn
 	chain             C.Chain
+	lastAdapterRemote string
+}
+
+func (c *packetConn) RemoteDestination() string {
+	return c.lastAdapterRemote
 }
 
 // Chains implements C.Connection
@@ -161,5 +171,5 @@ func (c *packetConn) AppendToChains(a C.ProxyAdapter) {
 }
 
 func newPacketConn(pc net.PacketConn, a C.ProxyAdapter) C.PacketConn {
-	return &packetConn{pc, []string{a.Name()}}
+	return &packetConn{pc, []string{a.Name()}, a.Addr()}
 }

constant/adapters.go

@@ -41,6 +41,7 @@ const (
 type Connection interface {
 	Chains() Chain
 	AppendToChains(adapter ProxyAdapter)
+	RemoteDestination() string
 }
 
 type Chain []string

tunnel/tunnel.go

@@ -288,14 +288,12 @@ func handleUDPConn(packet *inbound.PacketAdapter) {
 		}
 		pCtx.InjectPacketConn(rawPc)
 
-		actualProxy := proxy.Unwrap(metadata)
+		addr := rawPc.RemoteDestination()
-		if actualProxy != nil {
+		if dst, _, err := net.SplitHostPort(addr); err == nil {
-			if dst, _, err := net.SplitHostPort(actualProxy.Addr()); err == nil {
 			metadata.RemoteDst = dst
 		} else {
 			if addrError, ok := err.(*net.AddrError); ok && strings.Contains(addrError.Err, "missing port") {
-					metadata.RemoteDst = actualProxy.Addr()
+				metadata.RemoteDst = addr
-				}
 			}
 		}