Feature: use native syscall to bind interface on Linux and macOS

component/dialer/hook.go

@@ -3,20 +3,15 @@ package dialer
 import (
 	"errors"
 	"net"
-	"time"
-
-	"github.com/Dreamacro/clash/common/singledo"
 )
 
 type DialerHookFunc = func(dialer *net.Dialer) error
 type DialHookFunc = func(dialer *net.Dialer, network string, ip net.IP) error
-type ListenConfigHookFunc = func(*net.ListenConfig) error
-type ListenPacketHookFunc = func() (net.IP, error)
+type ListenPacketHookFunc = func(lc *net.ListenConfig, address string) (string, error)
 
 var (
 	DialerHook       DialerHookFunc
 	DialHook         DialHookFunc
-	ListenConfigHook ListenConfigHookFunc
 	ListenPacketHook ListenPacketHookFunc
 )
 
@@ -25,124 +20,24 @@ var (
 	ErrNetworkNotSupport = errors.New("network not support")
 )
 
-func lookupTCPAddr(ip net.IP, addrs []net.Addr) (*net.TCPAddr, error) {
-	ipv4 := ip.To4() != nil
-
-	for _, elm := range addrs {
-		addr, ok := elm.(*net.IPNet)
-		if !ok {
-			continue
-		}
-
-		addrV4 := addr.IP.To4() != nil
-
-		if addrV4 && ipv4 {
-			return &net.TCPAddr{IP: addr.IP, Port: 0}, nil
-		} else if !addrV4 && !ipv4 {
-			return &net.TCPAddr{IP: addr.IP, Port: 0}, nil
-		}
-	}
-
-	return nil, ErrAddrNotFound
-}
-
-func lookupUDPAddr(ip net.IP, addrs []net.Addr) (*net.UDPAddr, error) {
-	ipv4 := ip.To4() != nil
-
-	for _, elm := range addrs {
-		addr, ok := elm.(*net.IPNet)
-		if !ok {
-			continue
-		}
-
-		addrV4 := addr.IP.To4() != nil
-
-		if addrV4 && ipv4 {
-			return &net.UDPAddr{IP: addr.IP, Port: 0}, nil
-		} else if !addrV4 && !ipv4 {
-			return &net.UDPAddr{IP: addr.IP, Port: 0}, nil
-		}
-	}
-
-	return nil, ErrAddrNotFound
-}
-
 func ListenPacketWithInterface(name string) ListenPacketHookFunc {
-	single := singledo.NewSingle(5 * time.Second)
-
-	return func() (net.IP, error) {
-		elm, err, _ := single.Do(func() (interface{}, error) {
-			iface, err := net.InterfaceByName(name)
-			if err != nil {
-				return nil, err
-			}
-
-			addrs, err := iface.Addrs()
-			if err != nil {
-				return nil, err
-			}
-
-			return addrs, nil
-		})
-
-		if err != nil {
-			return nil, err
+	return func(lc *net.ListenConfig, address string) (string, error) {
+		err := bindIfaceToListenConfig(lc, name)
+		if err == errPlatformNotSupport {
+			address, err = fallbackBindToListenConfig(name)
 		}
 
-		addrs := elm.([]net.Addr)
-
-		for _, elm := range addrs {
-			addr, ok := elm.(*net.IPNet)
-			if !ok || addr.IP.To4() == nil {
-				continue
-			}
-
-			return addr.IP, nil
-		}
-
-		return nil, ErrAddrNotFound
+		return address, err
 	}
 }
 
 func DialerWithInterface(name string) DialHookFunc {
-	single := singledo.NewSingle(5 * time.Second)
-
 	return func(dialer *net.Dialer, network string, ip net.IP) error {
-		elm, err, _ := single.Do(func() (interface{}, error) {
-			iface, err := net.InterfaceByName(name)
-			if err != nil {
-				return nil, err
-			}
-
-			addrs, err := iface.Addrs()
-			if err != nil {
-				return nil, err
-			}
-
-			return addrs, nil
-		})
-
-		if err != nil {
-			return err
+		err := bindIfaceToDialer(dialer, name)
+		if err == errPlatformNotSupport {
+			err = fallbackBindToDialer(dialer, network, ip, name)
 		}
 
-		addrs := elm.([]net.Addr)
-
-		switch network {
-		case "tcp", "tcp4", "tcp6":
-			if addr, err := lookupTCPAddr(ip, addrs); err == nil {
-				dialer.LocalAddr = addr
-			} else {
-				return err
-			}
-		case "udp", "udp4", "udp6":
-			if addr, err := lookupUDPAddr(ip, addrs); err == nil {
-				dialer.LocalAddr = addr
-			} else {
-				return err
-			}
-		}
-
-		return nil
+		return err
 	}
 }