chore: decrease goroutine used in core tunnel

constant/listener.go

@@ -16,7 +16,7 @@ type MultiAddrListener interface {
 
 type InboundListener interface {
 	Name() string
-	Listen(tcpIn chan<- ConnContext, udpIn chan<- PacketAdapter, natTable NatTable) error
+	Listen(tunnel Tunnel) error
 	Close() error
 	Address() string
 	RawAddress() string

constant/tunnel.go

@@ -0,0 +1,10 @@
+package constant
+
+type Tunnel interface {
+	// HandleTCPConn will handle a tcp connection blocking
+	HandleTCPConn(connCtx ConnContext)
+	// HandleUDPPacket will handle a udp packet nonblocking
+	HandleUDPPacket(packet PacketAdapter)
+	// NatTable return nat table
+	NatTable() NatTable
+}