Xray-core: Add Lua script for dns and routing

https://github.com/XTLS/Xray-core/pull/6823

docs/en/config/dns.md

@@ -7,6 +7,7 @@ The built-in DNS module in Xray has three main purposes:
 - **Routing Phase:** Resolves domain names to IPs and matches rules based on the resolved IPs for traffic splitting.
   ::: details Detailed explanation
   Whether a domain name is resolved for IP-based routing depends on `routing.domainStrategy`. The built-in DNS server may be used for DNS queries only with the following values:
+
   - `"IPIfNonMatch"`: If no rule matches during the first routing pass, resolution occurs whenever the target includes a domain name and at least one rule contains an `ip` condition.
   - `"IPOnDemand"`: Resolution occurs when the target includes a domain name and a rule containing an `ip` condition is encountered.
 
@@ -14,6 +15,7 @@ The built-in DNS module in Xray has three main purposes:
 
 - **Outbound Phase:** Resolves target domain names for connections or for sending to a remote proxy server.
   ::: details Detailed explanation
+
   - For example, setting `targetStrategy` to `UseIP` in a VLESS outbound resolves the target domain of the proxied request through the local built-in DNS module, then sends the resolved IP to the remote proxy server.
   - Setting `sockopt.domainStrategy` to `UseIP` in a VLESS outbound resolves the VLESS server's domain through the built-in DNS module, then connects to the resolved IP.
   - Setting `sockopt.domainStrategy` to `UseIP` in a Freedom outbound resolves the request's target domain through the built-in DNS module, then connects to the resolved IP.
@@ -23,6 +25,7 @@ The built-in DNS module in Xray has three main purposes:
 
 - **TUN/Transparent Proxy DNS Traffic Hijacking:** Combines routing with the DNS outbound to hijack DNS traffic into this module; or uses [Tunnel](./inbounds/tunnel.md) to expose port 53 and act as a recursive DNS server.
   ::: details Detailed explanation
+
   - Only basic IP queries (A and AAAA records) are supported. CNAME records will be queried repeatedly until an A/AAAA record is returned. Other queries will not enter the built-in DNS server; instead, they may be discarded or transparently forwarded to other servers depending on your outbound configuration.
 
   :::
@@ -31,6 +34,8 @@ The built-in DNS module in Xray has three main purposes:
 
 The domain first undergoes a Hosts mapping check (see the `hosts` field). If the required IP is not found, the DNS server is used for the query.
 
+If `script` is configured, subsequent DNS queries are handled by a [Lua script](../development/lua/guide/dns.md), and the built-in processing flow below is skipped.
+
 The core then begins to build a list of servers, sorting them according to the requested domain based on the following rules.
 
 - Build List 1: Contains servers where the `domains` field successfully matches the requested domain, in the order they appear in the configuration file.
@@ -54,6 +59,7 @@ When executing a DNS query, the core will query the servers in the Final Server
       "baidu.com": "127.0.0.1",
       "dns.google": ["8.8.8.8", "8.8.4.4"]
     },
+    "script": "",
     "servers": [
       "8.8.8.8",
       "8.8.4.4",
@@ -107,6 +113,10 @@ The mapping target may be a domain name. When the core finishes matching and the
 
 The matching format (`domain:`, `full:`, etc.) is the same as the domain in the commonly used [Routing System](./routing.md#ruleobject). The difference is that without a prefix, it defaults to using the `full:` prefix (similar to the common hosts file syntax).
 
+> `script`: string
+
+Path to a Lua script file; defaults to an empty string. When set, the Lua script takes over the built-in DNS processing flow. See the [DNS Scripts guide](../development/lua/guide/dns.md) for usage.
+
 > `servers`: \[string | [DnsServerObject](#dnsserverobject) \]
 
 A list of DNS servers. Two types are supported: DNS address (string format) and [DnsServerObject](#dnsserverobject).
@@ -267,6 +277,7 @@ For query traffic generated by the built-in DNS, except for `localhost`, `fakedn
 
 ```json
 {
+  "id": "primary",
   "address": "1.2.3.4",
   "port": 5353,
   "domains": ["domain:xray.com"],
@@ -281,6 +292,10 @@ For query traffic generated by the built-in DNS, except for `localhost`, `fakedn
 }
 ```
 
+> `id`: string
+
+Server identifier; an empty string if omitted. Lua scripts use [`serverObj.ID`](../development/lua/reference/module-dns.md#id) to identify the upstream.
+
 > `address`: address
 
 A list of DNS servers. Two types are supported: DNS address (string format) and DnsServerObject.

docs/en/config/routing.md

@@ -15,6 +15,7 @@ For a more detailed analysis of the routing function: [Analysis of Routing (Part
   "routing": {
     "domainStrategy": "AsIs",
     "rules": [],
+    "script": "",
     "balancers": []
   }
 }
@@ -44,6 +45,10 @@ For each connection, routing will judge these rules from top to bottom. When the
 When no rule is matched, traffic is sent via the first outbound by default.
 :::
 
+> `script`: string
+
+Path to a Lua script file; defaults to an empty string. When set, the Lua script takes over outbound selection. See the [Routing Scripts guide](../development/lua/guide/routing.md) for usage.
+
 > `balancers`: \[ [BalancerObject](#balancerobject) \]
 
 An array, where each item is a load balancer configuration.