Feature: add dhcp type dns client (#1509)

component/dialer/bind_others.go

@@ -3,12 +3,91 @@
 
 package dialer
 
-import "net"
+import (
+	"net"
+	"strconv"
+	"strings"
 
-func bindIfaceToDialer(dialer *net.Dialer, ifaceName string) error {
-	return errPlatformNotSupport
+	"github.com/Dreamacro/clash/component/iface"
+)
+
+func lookupLocalAddr(ifaceName string, network string, destination net.IP, port int) (net.Addr, error) {
+	ifaceObj, err := iface.ResolveInterface(ifaceName)
+	if err != nil {
+		return nil, err
+	}
+
+	var addr *net.IPNet
+	switch network {
+	case "udp4", "tcp4":
+		addr, err = ifaceObj.PickIPv4Addr(destination)
+	case "tcp6", "udp6":
+		addr, err = ifaceObj.PickIPv6Addr(destination)
+	default:
+		if destination != nil {
+			if destination.To4() != nil {
+				addr, err = ifaceObj.PickIPv4Addr(destination)
+			} else {
+				addr, err = ifaceObj.PickIPv6Addr(destination)
+			}
+		} else {
+			addr, err = ifaceObj.PickIPv4Addr(destination)
+		}
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	if strings.HasPrefix(network, "tcp") {
+		return &net.TCPAddr{
+			IP:   addr.IP,
+			Port: port,
+		}, nil
+	} else if strings.HasPrefix(network, "udp") {
+		return &net.UDPAddr{
+			IP:   addr.IP,
+			Port: port,
+		}, nil
+	}
+
+	return nil, iface.ErrAddrNotFound
 }
 
-func bindIfaceToListenConfig(lc *net.ListenConfig, ifaceName string) error {
-	return errPlatformNotSupport
+func bindIfaceToDialer(ifaceName string, dialer *net.Dialer, network string, destination net.IP) error {
+	if !destination.IsGlobalUnicast() {
+		return nil
+	}
+
+	local := 0
+	if dialer.LocalAddr != nil {
+		_, port, err := net.SplitHostPort(dialer.LocalAddr.String())
+		if err == nil {
+			local, _ = strconv.Atoi(port)
+		}
+	}
+
+	addr, err := lookupLocalAddr(ifaceName, network, destination, local)
+	if err != nil {
+		return err
+	}
+
+	dialer.LocalAddr = addr
+
+	return nil
+}
+
+func bindIfaceToListenConfig(ifaceName string, _ *net.ListenConfig, network, address string) (string, error) {
+	_, port, err := net.SplitHostPort(address)
+	if err != nil {
+		port = "0"
+	}
+
+	local, _ := strconv.Atoi(port)
+
+	addr, err := lookupLocalAddr(ifaceName, network, nil, local)
+	if err != nil {
+		return "", err
+	}
+
+	return addr.String(), nil
 }