Fix compatibility with MPTCP

Author: nekohasekai

docs/configuration/inbound/tun.md

@@ -2,6 +2,10 @@
 icon: material/new-box
 ---
 
+!!! quote "Changes in sing-box 1.13.0"
+
+    :material-plus: [exclude_mptcp](#exclude_mptcp)
+
 !!! quote "Changes in sing-box 1.12.0"
 
     :material-plus: [loopback_address](#loopback_address)
@@ -63,6 +67,7 @@ icon: material/new-box
   "auto_redirect": true,
   "auto_redirect_input_mark": "0x2023",
   "auto_redirect_output_mark": "0x2024",
+  "exclude_mptcp": false,
   "loopback_address": [
     "10.7.0.1"
   ],
@@ -278,6 +283,20 @@ Connection output mark used by `auto_redirect`.
 
 `0x2024` is used by default.
 
+#### exclude_mptcp
+
+!!! question "Since sing-box 1.13.0"
+
+!!! quote ""
+
+    Only supported on Linux with nftables and requires `auto_route` and `auto_redirect` enabled.
+
+MPTCP cannot be transparently proxied due to protocol limitations.
+
+Such traffic is usually created by Apple systems.
+
+When enabled, MPTCP connections will bypass sing-box and connect directly, otherwise, will be rejected to avoid errors by default.
+
 #### loopback_address
 
 !!! question "Since sing-box 1.12.0"

docs/configuration/inbound/tun.zh.md

@@ -2,6 +2,10 @@
 icon: material/new-box
 ---
 
+!!! quote "sing-box 1.13.0 中的更改"
+
+    :material-plus: [exclude_mptcp](#exclude_mptcp)
+
 !!! quote "sing-box 1.12.0 中的更改"
 
     :material-plus: [loopback_address](#loopback_address)
@@ -63,6 +67,7 @@ icon: material/new-box
   "auto_redirect": true,
   "auto_redirect_input_mark": "0x2023",
   "auto_redirect_output_mark": "0x2024",
+  "exclude_mptcp": false,
   "loopback_address": [
     "10.7.0.1"
   ],
@@ -277,6 +282,20 @@ tun 接口的 IPv6 前缀。
 
 默认使用 `0x2024`。
 
+#### exclude_mptcp
+
+!!! question "自 sing-box 1.13.0 起"
+
+!!! quote ""
+
+    仅支持 Linux，且需要 nftables，`auto_route` 和 `auto_redirect` 已启用。 
+
+由于协议限制，MPTCP 无法被透明代理。
+
+此类流量通常由 Apple 系统创建。
+
+启用时，MPTCP 连接将绕过 sing-box 直接连接，否则，将被拒绝以避免错误。
+
 #### loopback_address
 
 !!! question "自 sing-box 1.12.0 起"

go.mod

@@ -33,7 +33,7 @@ require (
 	github.com/sagernet/sing-shadowsocks v0.2.8
 	github.com/sagernet/sing-shadowsocks2 v0.2.1
 	github.com/sagernet/sing-shadowtls v0.2.1-0.20250503051639-fcd445d33c11
-	github.com/sagernet/sing-tun v0.8.0-beta.10
+	github.com/sagernet/sing-tun v0.8.0-beta.10.0.20251017082645-b49e63f8efdb
 	github.com/sagernet/sing-vmess v0.2.8-0.20250909125414-3aed155119a1
 	github.com/sagernet/smux v1.5.34-mod.2
 	github.com/sagernet/tailscale v1.86.5-sing-box-1.13-mod.4

go.sum

@@ -171,8 +171,8 @@ 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 v0.8.0-beta.10 h1:sHqSXTvzKPDF67AwZdoBV5FA91tFdWGfA1AbenIbpA4=
-github.com/sagernet/sing-tun v0.8.0-beta.10/go.mod h1:eWETzl4AwaxGKiZTpDIDVJLTBz9cfIdoZwaZY1jlSjg=
+github.com/sagernet/sing-tun v0.8.0-beta.10.0.20251017082645-b49e63f8efdb h1:iHbtERRIZ8Tf2uzghiDioc13LYfxhZcjKtNn9zh2DRo=
+github.com/sagernet/sing-tun v0.8.0-beta.10.0.20251017082645-b49e63f8efdb/go.mod h1:eWETzl4AwaxGKiZTpDIDVJLTBz9cfIdoZwaZY1jlSjg=
 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 v1.5.34-mod.2 h1:gkmBjIjlJ2zQKpLigOkFur5kBKdV6bNRoFu2WkltRQ4=

option/tun.go

@@ -20,6 +20,7 @@ type TunInboundOptions struct {
 	AutoRedirect           bool                             `json:"auto_redirect,omitempty"`
 	AutoRedirectInputMark  FwMark                           `json:"auto_redirect_input_mark,omitempty"`
 	AutoRedirectOutputMark FwMark                           `json:"auto_redirect_output_mark,omitempty"`
+	ExcludeMPTCP           bool                             `json:"exclude_mptcp,omitempty"`
 	LoopbackAddress        badoption.Listable[netip.Addr]   `json:"loopback_address,omitempty"`
 	StrictRoute            bool                             `json:"strict_route,omitempty"`
 	RouteAddress           badoption.Listable[netip.Prefix] `json:"route_address,omitempty"`

protocol/tun/inbound.go

@@ -203,6 +203,7 @@ func NewInbound(ctx context.Context, router adapter.Router, logger log.ContextLo
 			IPRoute2RuleIndex:        ruleIndex,
 			AutoRedirectInputMark:    inputMark,
 			AutoRedirectOutputMark:   outputMark,
+			ExcludeMPTCP:             options.ExcludeMPTCP,
 			Inet4LoopbackAddress:     common.Filter(options.LoopbackAddress, netip.Addr.Is4),
 			Inet6LoopbackAddress:     common.Filter(options.LoopbackAddress, netip.Addr.Is6),
 			StrictRoute:              options.StrictRoute,