Make sockopt.interface work with UDP on Darwin

Author: 92613hjh

transport/internet/sockopt_darwin.go

@@ -1,7 +1,7 @@
 package internet
 
 import (
-	network "net"
+	gonet "net"
 	"os"
 	"syscall"
 	"unsafe"
@@ -108,14 +108,6 @@ func applyOutboundSocketOptions(network string, address string, fd uintptr, conf
 				return err
 			}
 		}
-		if config.Interface != "" {
-			InterfaceIndex := getInterfaceIndexByName(config.Interface)
-			if InterfaceIndex != 0 {
-				if err := unix.SetsockoptInt(int(fd), syscall.IPPROTO_IP, syscall.IP_BOUND_IF, InterfaceIndex); err != nil {
-					return errors.New("failed to set Interface").Base(err)
-				}
-			}
-		}
 
 		if config.TcpKeepAliveIdle > 0 || config.TcpKeepAliveInterval > 0 {
 			if config.TcpKeepAliveIdle > 0 {
@@ -138,6 +130,23 @@ func applyOutboundSocketOptions(network string, address string, fd uintptr, conf
 		}
 	}
 
+	if config.Interface != "" {
+		iface, err := gonet.InterfaceByName(config.Interface)
+
+		if err != nil {
+			return errors.New("failed to get interface ", config.Interface).Base(err)
+		}
+		if network == "tcp6" || network == "udp6" {
+			if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_IPV6, unix.IPV6_BOUND_IF, iface.Index); err != nil {
+				return errors.New("failed to set IPV6_BOUND_IF").Base(err)
+			}
+		} else {
+			if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_IP, unix.IP_BOUND_IF, iface.Index); err != nil {
+				return errors.New("failed to set IP_BOUND_IF").Base(err)
+			}
+		}
+	}
+
 	return nil
 }
 
@@ -152,14 +161,6 @@ func applyInboundSocketOptions(network string, fd uintptr, config *SocketConfig)
 				return err
 			}
 		}
-		if config.Interface != "" {
-			InterfaceIndex := getInterfaceIndexByName(config.Interface)
-			if InterfaceIndex != 0 {
-				if err := unix.SetsockoptInt(int(fd), syscall.IPPROTO_IP, syscall.IP_BOUND_IF, InterfaceIndex); err != nil {
-					return errors.New("failed to set Interface").Base(err)
-				}
-			}
-		}
 
 		if config.TcpKeepAliveIdle > 0 || config.TcpKeepAliveInterval > 0 {
 			if config.TcpKeepAliveIdle > 0 {
@@ -182,6 +183,23 @@ func applyInboundSocketOptions(network string, fd uintptr, config *SocketConfig)
 		}
 	}
 
+	if config.Interface != "" {
+		iface, err := gonet.InterfaceByName(config.Interface)
+
+		if err != nil {
+			return errors.New("failed to get interface ", config.Interface).Base(err)
+		}
+		if network == "tcp6" || network == "udp6" {
+			if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_IPV6, unix.IPV6_BOUND_IF, iface.Index); err != nil {
+				return errors.New("failed to set IPV6_BOUND_IF").Base(err)
+			}
+		} else {
+			if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_IP, unix.IP_BOUND_IF, iface.Index); err != nil {
+				return errors.New("failed to set IP_BOUND_IF").Base(err)
+			}
+		}
+	}
+
 	return nil
 }
 
@@ -224,24 +242,3 @@ func setReusePort(fd uintptr) error {
 	}
 	return nil
 }
-func getInterfaceIndexByName(name string) int {
-	ifaces, err := network.Interfaces()
-	if err == nil {
-		for _, iface := range ifaces {
-			if (iface.Flags&network.FlagUp == network.FlagUp) && (iface.Flags&network.FlagLoopback != network.FlagLoopback) {
-				addrs, _ := iface.Addrs()
-				for _, addr := range addrs {
-					if ipnet, ok := addr.(*network.IPNet); ok && !ipnet.IP.IsLoopback() {
-						if ipnet.IP.To4() != nil {
-							if iface.Name == name {
-								return iface.Index
-							}
-						}
-					}
-				}
-			}
-
-		}
-	}
-	return 0
-}

transport/internet/system_dialer.go

@@ -51,7 +51,7 @@ func hasBindAddr(sockopt *SocketConfig) bool {
 func (d *DefaultSystemDialer) Dial(ctx context.Context, src net.Address, dest net.Destination, sockopt *SocketConfig) (net.Conn, error) {
 	errors.LogDebug(ctx, "dialing to "+dest.String())
 
-	if dest.Network == net.Network_UDP && !hasBindAddr(sockopt) {
+	if dest.Network == net.Network_UDP && !hasBindAddr(sockopt) && sockopt.Interface == "" {
 		srcAddr := resolveSrcAddr(net.Network_UDP, src)
 		if srcAddr == nil {
 			srcAddr = &net.UDPAddr{