chore: code optimizations

cmd/config.go

@@ -63,10 +63,10 @@ type serverConfig struct {
 		User     string `json:"user"`
 		Password string `json:"password"`
 	} `json:"socks5_outbound"`
-	SocketConfig struct {
-		BindAddress  string `json:"bind_address"`
-		BindToDevice string `json:"bind_to_device"`
-	} `json:"socket_config"`
+	BindOutbound struct {
+		Address string `json:"address"`
+		Device  string `json:"device"`
+	} `json:"bind_outbound"`
 }
 
 func (c *serverConfig) Speed() (uint64, uint64, error) {

cmd/server.go

@@ -164,32 +164,26 @@ func server(config *serverConfig) {
 		}
 		transport.DefaultServerTransport.SOCKS5Client = ob
 	}
-	// socket settings
-	if config.SocketConfig.BindToDevice != "" {
-		iface, err := net.InterfaceByName(config.SocketConfig.BindToDevice)
+	// Bind outbound
+	if config.BindOutbound.Device != "" {
+		iface, err := net.InterfaceByName(config.BindOutbound.Device)
 		if err != nil {
 			logrus.WithFields(logrus.Fields{
 				"error": err,
-			}).Fatal("Failed to get bind_to_device")
+			}).Fatal("Failed to find the interface")
 		}
-		transport.DefaultServerTransport.Intf = iface
+		transport.DefaultServerTransport.LocalUDPIntf = iface
 		sockopt.BindDialer(transport.DefaultServerTransport.Dialer, iface)
 	}
-	if config.SocketConfig.BindAddress != "" {
-		ip := net.ParseIP(config.SocketConfig.BindAddress)
+	if config.BindOutbound.Address != "" {
+		ip := net.ParseIP(config.BindOutbound.Address)
 		if ip == nil {
 			logrus.WithFields(logrus.Fields{
 				"error": err,
-			}).Fatal("Failed to parse bind_address")
-		}
-		transport.DefaultServerTransport.Dialer.LocalAddr = &net.TCPAddr{
-			IP:   ip,
-			Port: 0,
-		}
-		transport.DefaultServerTransport.LocalAddrUDP = &net.UDPAddr{
-			IP:   ip,
-			Port: 0,
+			}).Fatal("Failed to parse the address")
 		}
+		transport.DefaultServerTransport.Dialer.LocalAddr = &net.TCPAddr{IP: ip}
+		transport.DefaultServerTransport.LocalUDPAddr = &net.UDPAddr{IP: ip}
 	}
 	// ACL
 	var aclEngine *acl.Engine

pkg/sockopt/sockopt_linux.go

@@ -8,9 +8,15 @@ import (
 )
 
 func bindRawConn(network string, c syscall.RawConn, bindIface *net.Interface) error {
-	return c.Control(func(fd uintptr) {
+	var err1, err2 error
+	err1 = c.Control(func(fd uintptr) {
 		if bindIface != nil {
-			unix.BindToDevice(int(fd), bindIface.Name)
+			err2 = unix.BindToDevice(int(fd), bindIface.Name)
 		}
 	})
+	if err1 != nil {
+		return err1
+	} else {
+		return err2
+	}
 }

pkg/sockopt/sockopt_others.go

@@ -3,8 +3,11 @@
 package sockopt
 
 import (
+	"errors"
 	"net"
 	"syscall"
 )
 
-func bindRawConn(network string, c syscall.RawConn, bindIface *net.Interface) error { return nil }
+func bindRawConn(network string, c syscall.RawConn, bindIface *net.Interface) error {
+	return errors.New("binding interface is not supported on the current system")
+}

pkg/transport/server.go

@@ -21,8 +21,8 @@ type ServerTransport struct {
 	PrefEnabled   bool
 	PrefIPv6      bool
 	PrefExclusive bool
-	LocalAddrUDP  *net.UDPAddr
-	Intf          *net.Interface
+	LocalUDPAddr  *net.UDPAddr
+	LocalUDPIntf  *net.Interface
 }
 
 // AddrEx is like net.TCPAddr or net.UDPAddr, but with additional domain information for SOCKS5.
@@ -167,12 +167,12 @@ func (st *ServerTransport) ListenUDP() (PUDPConn, error) {
 	if st.SOCKS5Client != nil {
 		return st.SOCKS5Client.ListenUDP()
 	} else {
-		conn, err := net.ListenUDP("udp", st.LocalAddrUDP)
+		conn, err := net.ListenUDP("udp", st.LocalUDPAddr)
 		if err != nil {
 			return nil, err
 		}
-		if st.Intf != nil {
-			err = sockopt.BindUDPConn("udp", conn, st.Intf)
+		if st.LocalUDPIntf != nil {
+			err = sockopt.BindUDPConn("udp", conn, st.LocalUDPIntf)
 			if err != nil {
 				conn.Close()
 				return nil, err