From 2e1d9a4f2ef4fb9c846614c53c6fd1d4a0b198e2 Mon Sep 17 00:00:00 2001
From: adlyq <2833154405@qq.com>
Date: Fri, 22 Apr 2022 22:25:45 +0800
Subject: [PATCH] fix: hotspot for android

---
 listener/listener.go                         |  5 +++-
 listener/tun/ipstack/commons/router_linux.go | 27 +++++++++++++++-----
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/listener/listener.go b/listener/listener.go
index 79732b66..9671bce9 100644
--- a/listener/listener.go
+++ b/listener/listener.go
@@ -398,7 +398,10 @@ func Cleanup() {
 	if tunStackListener != nil {
 		_ = tunStackListener.Close()
 		if runtime.GOOS == "android" {
-			_, _ = cmd.ExecCmd("ip rule del pref 5000")
+			prefs := []int{9000, 9001, 9002, 9003}
+			for _, pref := range prefs {
+				_, _ = cmd.ExecCmd(fmt.Sprintf("ip rule del pref %d", pref))
+			}
 		}
 	}
 }
diff --git a/listener/tun/ipstack/commons/router_linux.go b/listener/tun/ipstack/commons/router_linux.go
index 34281d86..1259ab75 100644
--- a/listener/tun/ipstack/commons/router_linux.go
+++ b/listener/tun/ipstack/commons/router_linux.go
@@ -7,6 +7,7 @@ import (
 	"github.com/Dreamacro/clash/log"
 	"net/netip"
 	"runtime"
+	"strconv"
 )
 
 func GetAutoDetectInterface() (string, error) {
@@ -39,21 +40,33 @@ func ConfigInterfaceAddress(dev device.Device, addr netip.Prefix, forceMTU int,
 }
 
 func configInterfaceRouting(interfaceName string, addr netip.Prefix) error {
+	linkIP := addr.Masked().Addr().Next()
 	if runtime.GOOS == "android" {
-		tableId := 1981801
+		const tableId = 1981801
 		for _, route := range defaultRoutes {
-			if _, err := cmd.ExecCmd(fmt.Sprintf("ip route add %s dev %s scope link table %d", route, interfaceName, tableId)); err != nil {
+			if err := execRouterCmd("add", route, interfaceName, linkIP.String(), strconv.Itoa(tableId)); err != nil {
 				return err
 			}
 		}
-		_, err := cmd.ExecCmd(fmt.Sprintf("ip rule add lookup %d suppress_prefixlength 0 pref 5000", tableId))
+		_, err := cmd.ExecCmd(fmt.Sprintf("ip rule add from 0.0.0.0 iif lo uidrange 0-4294967294 lookup %d pref 9000", tableId))
+		if err != nil {
+			log.Warnln("%s", err)
+		}
+		_, err = cmd.ExecCmd(fmt.Sprintf("ip rule add from %s iif lo uidrange 0-4294967294 lookup %d pref 9001", linkIP, tableId))
+		if err != nil {
+			log.Warnln("%s", err)
+		}
+		_, err = cmd.ExecCmd(fmt.Sprintf("ip rule add from all iif %s lookup main suppress_prefixlength 0 pref 9002", interfaceName))
+		if err != nil {
+			log.Warnln("%s", err)
+		}
+		_, err = cmd.ExecCmd(fmt.Sprintf("ip rule add not from all iif lo lookup %d pref 9003", tableId))
 		if err != nil {
 			log.Warnln("%s", err)
 		}
 	} else {
-		linkIP := addr.Masked().Addr().Next()
 		for _, route := range defaultRoutes {
-			if err := execRouterCmd("add", route, interfaceName, linkIP.String()); err != nil {
+			if err := execRouterCmd("add", route, interfaceName, linkIP.String(), "main"); err != nil {
 				return err
 			}
 		}
@@ -64,8 +77,8 @@ func configInterfaceRouting(interfaceName string, addr netip.Prefix) error {
 	return nil
 }
 
-func execRouterCmd(action, route string, interfaceName string, linkIP string) error {
-	cmdStr := fmt.Sprintf("ip route %s %s dev %s proto kernel scope link src %s", action, route, interfaceName, linkIP)
+func execRouterCmd(action, route, interfaceName, linkIP, table string) error {
+	cmdStr := fmt.Sprintf("ip route %s %s dev %s proto kernel scope link src %s table %s", action, route, interfaceName, linkIP, table)
 
 	_, err := cmd.ExecCmd(cmdStr)
 	return err