fix(libhttp): 服务器读超时防 Slowloris (P1-4)

- 新增 setHeaderTimeout()(default 10s) / setReadTimeout()(default 30s)，对齐 WAF
- doSSLHandshake 设置头超时覆盖握手，doRead 拆分为 async_read_header (头超时) + async_read (体超时)
- doWsRead 每次读取设置空闲超时，自动清理长期空闲连接
- 更新审计文档 P1-4 状态、README v3.4.2

libhttp/README.md

@@ -14,6 +14,7 @@ C++20 network library for the UniServe microservice framework, providing unified
 - **Thread Pool**: Multi-threaded I/O with `asio::strand` for thread safety
 - **Client Management**: WebSocket client tracking, broadcast, and targeted send
 - **WS Message Size Limit**: `setMaxWsMessageSize()` caps single WebSocket message (default 16MB, aligned with Beast; applies to server and proxy streams) to prevent OOM
+- **Read Timeouts (Slowloris Protection)**: `setHeaderTimeout()` (default 10s) / `setReadTimeout()` (default 30s) enforce two-stage header/body read timeouts plus WS idle timeout, aligned with WAF
 
 ### HttpClient
 - **HTTP Client**: Synchronous HTTP requests via libcurl (GET/POST/PUT/DELETE/PATCH/HEAD/OPTIONS)
@@ -172,6 +173,12 @@ void setStaticDirectory(const std::string& path);
 void setMaxWsMessageSize(std::size_t bytes);
 std::size_t getMaxWsMessageSize() const;
 
+// 入站读超时（防 Slowloris）。默认 10s（头）/ 30s（体），对齐 WAF。
+void setHeaderTimeout(std::chrono::seconds t);
+std::chrono::seconds getHeaderTimeout() const;
+void setReadTimeout(std::chrono::seconds t);
+std::chrono::seconds getReadTimeout() const;
+
 **WebSocket Routes**
 ```cpp
 void ws(const std::string& path, WebSocketMessageHandler handler);
@@ -288,6 +295,7 @@ using WebSocketClientBase = HttpClient;
 
 ## Version History
 
+- **v3.4.2**: 服务器读超时防 Slowloris（P1-4）。新增 `setHeaderTimeout()`（默认 10s）/`setReadTimeout()`（默认 30s）；`doRead` 两阶段读（`async_read_header` 头超时 → `async_read` 体超时），`doSSLHandshake` 覆盖握手超时，`doWsRead` 设 WS 空闲超时，对齐 WAF ReadHeaderTimeout/ReadTimeout。
 - **v3.4.1**: WebSocket 单条消息大小限制（P1-3）。新增 `setMaxWsMessageSize()`/`getMaxWsMessageSize()`（默认 16MB，与 Beast 默认一致），服务端 `doWsUpgrade`/`doWssUpgrade` 与代理 `onProxyConnect`/`onProxySslHandshake` 创建流后调用 `read_message_max()`，超限消息由 Beast 在分配内存前拒绝并关闭连接，防 OOM。
 - **v3.4.0**: HttpClient 响应大小限制（防 OOM）。`request_stream_sync` 改为真流式（按块回调，不二次缓冲）；新增 `set_max_response_size()`/`get_max_response_size()`（默认 10MB，对齐 WAF，0 表示不限制），超限时 `write_callback` 返回 0 中止传输并抛异常。
 - **v3.3.0**: Split HttpServer into 6 modular translation units by functional area (core/lifecycle, listener, routes, request dispatch, WS management, WS session/proxy) for dramatically faster incremental builds. Added internal detail header `inc/us/detail/HttpServerImpl.hpp` for shared definitions across TU boundaries.

libhttp/inc/us/HttpServer.hpp

@@ -21,6 +21,7 @@
 #include <mutex>
 #include <regex>
 #include <deque>
+#include <chrono>
 
 namespace pmc {
 namespace net {
@@ -124,6 +125,13 @@ public:
     void setMaxWsMessageSize(std::size_t bytes) { max_ws_message_size_ = bytes; }
     std::size_t getMaxWsMessageSize() const { return max_ws_message_size_; }
 
+    // 入站读超时（防 Slowloris，P1-4）。默认与 WAF 对齐：头 10s、体 30s。
+    // 头超时覆盖 TCP 连接建立 + SSL 握手 + 请求头读取；体超时覆盖请求体读取。
+    void setHeaderTimeout(std::chrono::seconds t) { header_timeout_ = t; }
+    std::chrono::seconds getHeaderTimeout() const { return header_timeout_; }
+    void setReadTimeout(std::chrono::seconds t) { read_timeout_ = t; }
+    std::chrono::seconds getReadTimeout() const { return read_timeout_; }
+
     class debug {
     public:
         static void print_all_header_fields(const http::request<http::string_body>& req);
@@ -140,6 +148,8 @@ private:
 
     std::size_t max_body_size_ = 10 * 1024 * 1024; // 默认 10MB,与 WAF 对齐
     std::size_t max_ws_message_size_ = 16 * 1024 * 1024; // 默认 16MB,与 Beast 默认一致
+    std::chrono::seconds header_timeout_{10}; // 头/握手超时，防 Slowloris（对齐 WAF ReadHeaderTimeout）
+    std::chrono::seconds read_timeout_{30};   // 体超时（对齐 WAF ReadTimeout）
 
     bool ssl_enabled_{false};
     std::string cert_file_;

libhttp/inc/us/detail/HttpServerImpl.hpp

@@ -67,6 +67,7 @@ private:
     void close();
     void doSSLHandshake();
     void doRead();
+    void doReadBody();
     void handleRead(beast::error_code ec);
     bool isWebSocketUpgrade(const http::request<http::string_body>& req);
     void doWsUpgrade();

libhttp/src/HttpServer_Request.cpp

@@ -167,6 +167,13 @@ void HttpServer::Session::doSSLHandshake() {
     std::cout << "[SSL] Starting handshake for "
               << remote_ip_ << ":" << remote_port_ << std::endl;
 
+    // P1-4：设置头超时（TCP 连接完成后，覆盖 SSL 握手 + 请求头读取）
+    if (ssl_enabled_ && ssl_stream_) {
+        ssl_stream_->next_layer().expires_after(server_->getHeaderTimeout());
+    } else {
+        stream_.expires_after(server_->getHeaderTimeout());
+    }
+
     ssl_stream_->async_handshake(
         asio::ssl::stream_base::server,
         [self](beast::error_code ec) {
@@ -193,6 +200,37 @@ void HttpServer::Session::doRead() {
     parser_.emplace();
     parser_->body_limit(server_->max_body_size_);
 
+    // P1-4：阶段1 读请求头（头超时，防 Slowloris）
+    if (ssl_enabled_ && ssl_stream_) {
+        ssl_stream_->next_layer().expires_after(server_->getHeaderTimeout());
+    } else {
+        stream_.expires_after(server_->getHeaderTimeout());
+    }
+
+    auto on_header = [self](beast::error_code ec, std::size_t) {
+        if (ec) {
+            self->handleRead(ec);
+            return;
+        }
+        // 阶段2 读请求体：切换到体超时
+        if (self->ssl_enabled_ && self->ssl_stream_) {
+            self->ssl_stream_->next_layer().expires_after(self->server_->getReadTimeout());
+        } else {
+            self->stream_.expires_after(self->server_->getReadTimeout());
+        }
+        self->doReadBody();
+    };
+
+    if (ssl_enabled_ && ssl_stream_) {
+        http::async_read_header(*ssl_stream_, buffer_, *parser_, on_header);
+    } else {
+        http::async_read_header(stream_, buffer_, *parser_, on_header);
+    }
+}
+
+void HttpServer::Session::doReadBody() {
+    auto self = shared_from_this();
+
     auto on_read = [self](beast::error_code ec, std::size_t) {
         if (!ec) self->request_ = self->parser_->release();
         self->handleRead(ec);

libhttp/src/HttpServer_WsSession.cpp

@@ -74,6 +74,9 @@ void HttpServer::Session::doWsRead() {
     auto self = shared_from_this();
     ws_buffer_.consume(ws_buffer_.size());
 
+    // P1-4：WS 读取设置空闲超时，清理长期不发消息的连接
+    stream_.expires_after(server_->getReadTimeout());
+
     if (ssl_enabled_ && wss_stream_) {
         wss_stream_->async_read(
             ws_buffer_,