Cleanup

cmd/tun/main.go

@@ -24,12 +24,13 @@ var (
 )
 
 func init() {
+	iface, _ := control.DefaultInterfaceName()
 	flag.IntVar(&mark, "fwmark", 0, "Set firewall MARK (Linux only)")
 	flag.IntVar(&conf.MTU, "mtu", 0, "Set device maximum transmission unit (MTU)")
 	flag.StringVar(&conf.Device, "device", "", "Use this device")
 	flag.StringVar(&conf.Name, "name", "", "Use this device name")
 	flag.StringVar(&route, "route", "10.0.0.0/8", "Set the route")
-	flag.StringVar(&interfaceName, "interface", "", "Use network INTERFACE (Linux/MacOS only)")
+	flag.StringVar(&interfaceName, "interface", iface, "Use network INTERFACE (Linux/MacOS only)")
 	flag.Parse()
 }
 
@@ -60,7 +61,6 @@ func main() {
 	conf.Logger = logger
 	conf.Dialer = WrapDialerFunc(func(ctx context.Context, network, address string) (net.Conn, error) {
 		logger.Println("Dial", network, address)
-		return dialer.DialContext(ctx, network, "www.baidu.com:80")
 		return dialer.DialContext(ctx, network, address)
 	})
 	conf.ListenPacket = &listenConfig

control/interface_name.go

@@ -0,0 +1,26 @@
+package control
+
+import (
+	"net"
+	"strings"
+)
+
+func DefaultInterfaceName() (string, error) {
+	ifaces, err := net.Interfaces()
+	if err != nil {
+		return "", err
+	}
+
+	for _, iface := range ifaces {
+		if iface.Flags&net.FlagUp == 0 {
+			continue
+		}
+		if iface.Flags&net.FlagBroadcast == 0 {
+			continue
+		}
+		if strings.HasPrefix(iface.Name, "en") || strings.HasPrefix(iface.Name, "eth") {
+			return iface.Name, nil
+		}
+	}
+	return "", nil
+}

go.mod

@@ -5,7 +5,6 @@ go 1.17
 require (
 	golang.org/x/sys v0.0.0-20220204135822-1c1b9b1eba6a
 	golang.org/x/time v0.0.0-20211116232009-f0f3c7e86c11
-	golang.zx2c4.com/wintun v0.0.0-20211104114900-415007cec224
 	golang.zx2c4.com/wireguard v0.0.0-20220202223031-3b95c81cc178
 	gvisor.dev/gvisor v0.0.0-20220208035940-56a131734b85
 )
@@ -13,4 +12,5 @@ require (
 require (
 	github.com/google/btree v1.0.1 // indirect
 	golang.org/x/net v0.0.0-20220127200216-cd36cc0744dd // indirect
+	golang.zx2c4.com/wintun v0.0.0-20211104114900-415007cec224 // indirect
 )