Allow routing_mark when auto_redirect is enabled

adapter/network.go

@@ -24,6 +24,7 @@ type NetworkManager interface {
 	DefaultOptions() NetworkOptions
 	RegisterAutoRedirectOutputMark(mark uint32) error
 	AutoRedirectOutputMark() uint32
+	AutoRedirectMarkMask() uint32
 	AutoRedirectOutputMarkFunc() control.Func
 	NetworkMonitor() tun.NetworkUpdateMonitor
 	InterfaceMonitor() tun.DefaultInterfaceMonitor

common/dialer/default.go

@@ -228,12 +228,19 @@ func setMarkWrapper(networkManager adapter.NetworkManager, mark uint32, isDefaul
 		return control.RoutingMark(mark)
 	}
 	return func(network, address string, conn syscall.RawConn) error {
-		if networkManager.AutoRedirectOutputMark() != 0 {
-			if isDefault {
-				return E.New("`route.default_mark` is conflict with `tun.auto_redirect`")
-			} else {
-				return E.New("`routing_mark` is conflict with `tun.auto_redirect`")
+		autoMark := networkManager.AutoRedirectOutputMark()
+		if autoMark != 0 {
+			maskReserved := networkManager.AutoRedirectMarkMask()
+			if mark&maskReserved != 0 {
+				if isDefault {
+					return E.New("`route.default_mark` uses bits reserved for `tun.auto_redirect` (low 16 bits)")
+				}
+				return E.New("`routing_mark` uses bits reserved for `tun.auto_redirect` (low 16 bits)")
 			}
+			return control.Raw(conn, func(fd uintptr) error {
+				current, _ := syscall.GetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK)
+				return syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK, current|int(mark))
+			})
 		}
 		return control.RoutingMark(mark)(network, address, conn)
 	}

go.mod

@@ -166,3 +166,5 @@ require (
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	lukechampine.com/blake3 v1.3.0 // indirect
 )
+
+replace github.com/sagernet/sing-tun => github.com/loncharles/sing-tun v0.0.0-20260513193456-240481b009fd

go.sum

@@ -124,6 +124,8 @@ github.com/libdns/libdns v1.1.1 h1:wPrHrXILoSHKWJKGd0EiAVmiJbFShguILTg9leS/P/U=
 github.com/libdns/libdns v1.1.1/go.mod h1:4Bj9+5CQiNMVGf87wjX4CY3HQJypUHRuLvlsfsZqLWQ=
 github.com/logrusorgru/aurora v2.0.3+incompatible h1:tOpm7WcpBTn4fjmVfgpQq0EfczGlG91VSDkswnjF5A8=
 github.com/logrusorgru/aurora v2.0.3+incompatible/go.mod h1:7rIyQOR62GCctdiQpZ/zOJlFyk6y+94wXzv6RNZgaR4=
+github.com/loncharles/sing-tun v0.0.0-20260513193456-240481b009fd h1:Fx6u/em9g9k9gPgz/5iRSt+Kt+XQV7lIqIjorRhWu2U=
+github.com/loncharles/sing-tun v0.0.0-20260513193456-240481b009fd/go.mod h1:QvarqUtHfj1ULaRR+6kZOS/OoCE+pYGq67A5tyIy+dQ=
 github.com/mdlayher/netlink v1.9.0 h1:G8+GLq2x3v4D4MVIqDdNUhTUC7TKiCy/6MDkmItfKco=
 github.com/mdlayher/netlink v1.9.0/go.mod h1:YBnl5BXsCoRuwBjKKlZ+aYmEoq0r12FDA/3JC+94KDg=
 github.com/mdlayher/socket v0.5.1 h1:VZaqt6RkGkt2OE9l3GcC6nZkqD3xKeQLyfleW/uBcos=
@@ -248,8 +250,6 @@ github.com/sagernet/sing-shadowsocks2 v0.2.1 h1:dWV9OXCeFPuYGHb6IRqlSptVnSzOelnq
 github.com/sagernet/sing-shadowsocks2 v0.2.1/go.mod h1:RnXS0lExcDAovvDeniJ4IKa2IuChrdipolPYWBv9hWQ=
 github.com/sagernet/sing-shadowtls v0.2.1-0.20250503051639-fcd445d33c11 h1:tK+75l64tm9WvEFrYRE1t0YxoFdWQqw/h7Uhzj0vJ+w=
 github.com/sagernet/sing-shadowtls v0.2.1-0.20250503051639-fcd445d33c11/go.mod h1:sWqKnGlMipCHaGsw1sTTlimyUpgzP4WP3pjhCsYt9oA=
-github.com/sagernet/sing-tun v0.8.9 h1:ixFKKUGdVcJl4wb0xbL36hobiw9l6DIH497EQf5ILpM=
-github.com/sagernet/sing-tun v0.8.9/go.mod h1:QvarqUtHfj1ULaRR+6kZOS/OoCE+pYGq67A5tyIy+dQ=
 github.com/sagernet/sing-vmess v0.2.8-0.20250909125414-3aed155119a1 h1:aSwUNYUkVyVvdmBSufR8/nRFonwJeKSIROxHcm5br9o=
 github.com/sagernet/sing-vmess v0.2.8-0.20250909125414-3aed155119a1/go.mod h1:P11scgTxMxVVQ8dlM27yNm3Cro40mD0+gHbnqrNGDuY=
 github.com/sagernet/smux v1.5.50-sing-box-mod.1 h1:XkJcivBC9V4wBjiGXIXZ229aZCU1hzcbp6kSkkyQ478=

route/network.go

@@ -41,6 +41,7 @@ type NetworkManager struct {
 	autoDetectInterface    bool
 	defaultOptions         adapter.NetworkOptions
 	autoRedirectOutputMark uint32
+	autoRedirectMarkMask   uint32
 	networkMonitor         tun.NetworkUpdateMonitor
 	interfaceMonitor       tun.DefaultInterfaceMonitor
 	packageManager         tun.PackageManager
@@ -385,19 +386,27 @@ func (r *NetworkManager) RegisterAutoRedirectOutputMark(mark uint32) error {
 		return E.New("only one auto-redirect can be configured")
 	}
 	r.autoRedirectOutputMark = mark
+	r.autoRedirectMarkMask = tun.AutoRedirectMarkMask
 	return nil
 }
 
 func (r *NetworkManager) AutoRedirectOutputMark() uint32 {
 	return r.autoRedirectOutputMark
 }
 
+func (r *NetworkManager) AutoRedirectMarkMask() uint32 {
+	return r.autoRedirectMarkMask
+}
+
 func (r *NetworkManager) AutoRedirectOutputMarkFunc() control.Func {
 	return func(network, address string, conn syscall.RawConn) error {
 		if r.autoRedirectOutputMark == 0 {
 			return nil
 		}
-		return control.RoutingMark(r.autoRedirectOutputMark)(network, address, conn)
+		return control.Raw(conn, func(fd uintptr) error {
+			current, _ := syscall.GetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK)
+			return syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK, current|int(r.autoRedirectOutputMark))
+		})
 	}
 }