From cf5709aab10e6523be3cf76da2e114773eafc610 Mon Sep 17 00:00:00 2001
From: metacubex <maze.y2b@gmail.com>
Date: Sat, 3 Dec 2022 00:10:50 +0800
Subject: [PATCH] fix: a temporary solution for error reporting when enabling
 tun for devices that do not have an ipv6 environment.

---
 config/config.go |  4 ++++
 config/utils.go  | 23 +++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/config/config.go b/config/config.go
index bb8c65f44..f5efc936b 100644
--- a/config/config.go
+++ b/config/config.go
@@ -1289,6 +1289,10 @@ func parseTun(rawTun RawTun, general *General) error {
 	}
 	tunAddressPrefix = netip.PrefixFrom(tunAddressPrefix.Addr(), 30)
 
+	if !general.IPv6 || !verifyIP6() {
+		rawTun.Inet6Address = nil
+	}
+
 	general.Tun = Tun{
 		Enable:              rawTun.Enable,
 		Device:              rawTun.Device,
diff --git a/config/utils.go b/config/utils.go
index 1d49552fe..2c470618a 100644
--- a/config/utils.go
+++ b/config/utils.go
@@ -2,6 +2,7 @@ package config
 
 import (
 	"fmt"
+	"net"
 	"strings"
 
 	"github.com/Dreamacro/clash/adapter/outboundgroup"
@@ -146,3 +147,25 @@ func proxyGroupsDagSort(groupsConfig []map[string]any) error {
 	}
 	return fmt.Errorf("loop is detected in ProxyGroup, please check following ProxyGroups: %v", loopElements)
 }
+
+func verifyIP6() bool {
+	addrs, err := net.InterfaceAddrs()
+	if err != nil {
+		return false
+	}
+	for _, addr := range addrs {
+		ipNet, isIpNet := addr.(*net.IPNet)
+		if isIpNet && !ipNet.IP.IsLoopback() {
+			if ipNet.IP.To16() != nil {
+				s := ipNet.IP.String()
+				for i := 0; i < len(s); i++ {
+					switch s[i] {
+					case ':':
+						return true
+					}
+				}
+			}
+		}
+	}
+	return false
+}