From e71059d2454d3df4b1ea2ee4173448e0d7655801 Mon Sep 17 00:00:00 2001
From: Viktor Liu <viktor@netbird.io>
Date: Wed, 22 May 2024 12:32:01 +0200
Subject: [PATCH] Add dummy ipv6 to macos interface (#2025)

---
 client/internal/routemanager/systemops_darwin.go |  5 -----
 iface/iface_test.go                              | 14 +++++++++++++-
 iface/tun_darwin.go                              | 11 ++++++++---
 3 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/client/internal/routemanager/systemops_darwin.go b/client/internal/routemanager/systemops_darwin.go
index 017dc6c28..ee4196a0c 100644
--- a/client/internal/routemanager/systemops_darwin.go
+++ b/client/internal/routemanager/systemops_darwin.go
@@ -43,11 +43,6 @@ func routeCmd(action string, prefix netip.Prefix, nexthop netip.Addr, intf *net.
 	}
 	if prefix.Addr().Is6() {
 		inet = "-inet6"
-		// Special case for IPv6 split default route, pointing to the wg interface fails
-		// TODO: Remove once we have IPv6 support on the interface
-		if prefix.Bits() == 1 {
-			intf = &net.Interface{Name: "lo0"}
-		}
 	}
 
 	args := []string{"-n", action, inet, network}
diff --git a/iface/iface_test.go b/iface/iface_test.go
index 3fc250637..f227eaf83 100644
--- a/iface/iface_test.go
+++ b/iface/iface_test.go
@@ -3,6 +3,7 @@ package iface
 import (
 	"fmt"
 	"net"
+	"net/netip"
 	"testing"
 	"time"
 
@@ -79,8 +80,19 @@ func TestWGIface_UpdateAddr(t *testing.T) {
 		t.Error(err)
 	}
 
-	assert.Equal(t, addr, addrs[0].String())
+	var found bool
+	for _, a := range addrs {
+		prefix, err := netip.ParsePrefix(a.String())
+		assert.NoError(t, err)
+		if prefix.Addr().Is4() {
+			found = true
+			assert.Equal(t, addr, prefix.String())
+		}
+	}
 
+	if !found {
+		t.Fatal("v4 address not found")
+	}
 }
 
 func getIfaceAddrs(ifaceName string) ([]net.Addr, error) {
diff --git a/iface/tun_darwin.go b/iface/tun_darwin.go
index bac14986f..8dc10bd0e 100644
--- a/iface/tun_darwin.go
+++ b/iface/tun_darwin.go
@@ -1,5 +1,4 @@
 //go:build !ios
-// +build !ios
 
 package iface
 
@@ -121,13 +120,19 @@ func (t *tunDevice) Wrapper() *DeviceWrapper {
 func (t *tunDevice) assignAddr() error {
 	cmd := exec.Command("ifconfig", t.name, "inet", t.address.IP.String(), t.address.IP.String())
 	if out, err := cmd.CombinedOutput(); err != nil {
-		log.Infof(`adding address command "%v" failed with output %s and error: `, cmd.String(), out)
+		log.Errorf("adding address command '%v' failed with output: %s", cmd.String(), out)
 		return err
 	}
 
+	// dummy ipv6 so routing works
+	cmd = exec.Command("ifconfig", t.name, "inet6", "fe80::/64")
+	if out, err := cmd.CombinedOutput(); err != nil {
+		log.Debugf("adding address command '%v' failed with output: %s", cmd.String(), out)
+	}
+
 	routeCmd := exec.Command("route", "add", "-net", t.address.Network.String(), "-interface", t.name)
 	if out, err := routeCmd.CombinedOutput(); err != nil {
-		log.Printf(`adding route command "%v" failed with output %s and error: `, routeCmd.String(), out)
+		log.Errorf("adding route command '%v' failed with output: %s", routeCmd.String(), out)
 		return err
 	}
 	return nil