sing-box/docs/examples/tun.md

```json
{
  "dns": {
    "servers": [
      {
        "tag": "google",
        "address": "tls://8.8.8.8"
      },
      {
        "tag": "local",
        "address": "223.5.5.5",
        "detour": "direct"
      },
      {
        "tag": "block",
        "address": "rcode://success"
      }
    ],
    "rules": [
      {
        "geosite": "category-ads-all",
        "server": "block",
        "disable_cache": true
      },
      {
        "outbound": "any",
        "server": "local"
      },
      {
        "geosite": "cn",
        "server": "local"
      }
    ],
    "strategy": "ipv4_only"
  },
  "inbounds": [
    {
      "type": "tun",
      "inet4_address": "172.19.0.1/30",
      "auto_route": true,
      "strict_route": false,
      "sniff": true
    }
  ],
  "outbounds": [
    {
      "type": "shadowsocks",
      "tag": "proxy",
      "server": "mydomain.com",
      "server_port": 8080,
      "method": "2022-blake3-aes-128-gcm",
      "password": "8JCsPssfgS8tiRwiMlhARg=="
    },
    {
      "type": "direct",
      "tag": "direct"
    },
    {
      "type": "block",
      "tag": "block"
    },
    {
      "type": "dns",
      "tag": "dns-out"
    }
  ],
  "route": {
    "rules": [
      {
        "protocol": "dns",
        "outbound": "dns-out"
      },
      {
        "geosite": "cn",
        "geoip": [
          "private",
          "cn"
        ],
        "outbound": "direct"
      },
      {
        "geosite": "category-ads-all",
        "outbound": "block"
      }
    ],
    "auto_detect_interface": true
  }
}
```