sing-box/docs/configuration/inbound/tun.md

!!! quote ""

Only supported on Linux, Windows and macOS.

Structure

{
  "type": "tun",
  "tag": "tun-in",
  "interface_name": "tun0",
  "inet4_address": "172.19.0.1/30",
  "inet6_address": "fdfe:dcba:9876::1/126",
  "mtu": 9000,
  "auto_route": true,
  "strict_route": true,
  "inet4_route_address": [
    "0.0.0.0/1",
    "128.0.0.0/1"
  ],
  "inet6_route_address": [
    "::/1",
    "8000::/1"
  ],
  "inet4_route_exclude_address": [
    "192.168.0.0/16"
  ],
  "inet6_route_exclude_address": [
    "fc00::/7"
  ],
  "endpoint_independent_nat": false,
  "udp_timeout": "5m",
  "stack": "system",
  "include_interface": [
    "lan0"
  ],
  "exclude_interface": [
    "lan1"
  ],
  "include_uid": [
    0
  ],
  "include_uid_range": [
    "1000-99999"
  ],
  "exclude_uid": [
    1000
  ],
  "exclude_uid_range": [
    "1000-99999"
  ],
  "include_android_user": [
    0,
    10
  ],
  "include_package": [
    "com.android.chrome"
  ],
  "exclude_package": [
    "com.android.captiveportallogin"
  ],
  "platform": {
    "http_proxy": {
      "enabled": false,
      "server": "127.0.0.1",
      "server_port": 8080
    }
  },
  
  ... // Listen Fields
}

!!! note ""

You can ignore the JSON Array [] tag when the content is only one item

!!! warning ""

If tun is running in non-privileged mode, addresses and MTU will not be configured automatically, please make sure the settings are accurate.

Fields

interface_name

Virtual device name, automatically selected if empty.

inet4_address

==Required==

IPv4 prefix for the tun interface.

inet6_address

IPv6 prefix for the tun interface.

mtu

The maximum transmission unit.

auto_route

Set the default route to the Tun.

!!! quote ""

To avoid traffic loopback, set `route.auto_detect_interface` or `route.default_interface` or `outbound.bind_interface`

!!! note "Use with Android VPN"

By default, VPN takes precedence over tun. To make tun go through VPN, enable `route.override_android_vpn`.

strict_route

Enforce strict routing rules when auto_route is enabled:

In Linux:

• Let unsupported network unreachable
• Route all connections to tun

It prevents address leaks and makes DNS hijacking work on Android, but your device will not be accessible by others.

In Windows:

• Add firewall rules to prevent DNS leak caused by Windows' ordinary multihomed DNS resolution behavior

It may prevent some applications (such as VirtualBox) from working properly in certain situations.

inet4_route_address

Use custom routes instead of default when auto_route is enabled.

inet6_route_address

Use custom routes instead of default when auto_route is enabled.

inet4_route_exclude_address

Exclude custom routes when auto_route is enabled.

inet6_route_exclude_address

Exclude custom routes when auto_route is enabled.

endpoint_independent_nat

!!! info ""

This item is only available on the gvisor stack, other stacks are endpoint-independent NAT by default.

Enable endpoint-independent NAT.

Performance may degrade slightly, so it is not recommended to enable on when it is not needed.

udp_timeout

UDP NAT expiration time in seconds, default is 300 (5 minutes).

stack

TCP/IP stack.

Stack	Description	Status
system	Sometimes better performance	recommended
gVisor	Better compatibility, based on google/gvisor	recommended
mixed	Mixed system TCP stack and gVisor UDP stack	recommended
LWIP	Based on eycorsican/go-tun2socks	upstream archived

!!! warning ""

LWIP stacks is not included by default, see [Installation](/installation/build-from-source/#build-tags).

include_interface

!!! quote ""

Interface rules are only supported on Linux and require auto_route.

Limit interfaces in route. Not limited by default.

Conflict with exclude_interface.

exclude_interface

Exclude interfaces in route.

Conflict with include_interface.

include_uid

!!! quote ""

UID rules are only supported on Linux and require auto_route.

Limit users in route. Not limited by default.

include_uid_range

Limit users in route, but in range.

exclude_uid

Exclude users in route.

exclude_uid_range

Exclude users in route, but in range.

include_android_user

!!! quote ""

Android user and package rules are only supported on Android and require auto_route.

Limit android users in route.

Common user	ID
Main	0
Work Profile	10

include_package

Limit android packages in route.

exclude_package

Exclude android packages in route.

platform

Platform-specific settings, provided by client applications.

platform.http_proxy

System HTTP proxy settings.

Listen Fields

See Listen Fields for details.