fix(libhttp): WebSocket 发送/代理队列上限防 OOM (P1-6)

- 新增 setMaxWsQueueSize()(default 1000)，每个入队点检查
- wsSend / onProxyReadClient / onProxyReadBackend 超限关闭连接
- 更新审计文档 P1-6 状态、README v3.4.3

libhttp/README.md

@@ -15,6 +15,7 @@ C++20 network library for the UniServe microservice framework, providing unified
 - **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
+- **WS Queue Size Limit**: `setMaxWsQueueSize()` (default 1000) caps WS send / proxy queues; slow consumers get disconnected to prevent unbounded-memory OOM
 
 ### HttpClient
 - **HTTP Client**: Synchronous HTTP requests via libcurl (GET/POST/PUT/DELETE/PATCH/HEAD/OPTIONS)
@@ -179,6 +180,10 @@ std::chrono::seconds getHeaderTimeout() const;
 void setReadTimeout(std::chrono::seconds t);
 std::chrono::seconds getReadTimeout() const;
 
+// WS 发送/代理队列上限（条数）。默认 1000；超限判定慢消费者并关闭连接（防 OOM）。
+void setMaxWsQueueSize(std::size_t n);
+std::size_t getMaxWsQueueSize() const;
+
 **WebSocket Routes**
 ```cpp
 void ws(const std::string& path, WebSocketMessageHandler handler);
@@ -295,6 +300,7 @@ using WebSocketClientBase = HttpClient;
 
 ## Version History
 
+- **v3.4.3**: WebSocket 发送/代理队列上限（P1-6）。新增 `setMaxWsQueueSize()`（默认 1000）；`wsSend` / `onProxyReadClient` / `onProxyReadBackend` 入队前检查，超限判定慢消费者并关闭连接，防止无界队列内存耗尽。
 - **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。

libhttp/inc/us/HttpServer.hpp

@@ -132,6 +132,11 @@ public:
     void setReadTimeout(std::chrono::seconds t) { read_timeout_ = t; }
     std::chrono::seconds getReadTimeout() const { return read_timeout_; }
 
+    // WS 发送/代理队列上限（条数）。默认 1000。防止慢消费者导致无界队列内存耗尽（P1-6）。
+    // 超限时判定为慢消费者，关闭对应连接。
+    void setMaxWsQueueSize(std::size_t n) { max_ws_queue_size_ = n; }
+    std::size_t getMaxWsQueueSize() const { return max_ws_queue_size_; }
+
     class debug {
     public:
         static void print_all_header_fields(const http::request<http::string_body>& req);
@@ -150,6 +155,7 @@ private:
     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）
+    std::size_t max_ws_queue_size_ = 1000;    // WS 发送/代理队列上限，防慢消费者 OOM（P1-6）
 
     bool ssl_enabled_{false};
     std::string cert_file_;

libhttp/src/HttpServer_WsSession.cpp

@@ -8,6 +8,14 @@ namespace net {
 void HttpServer::Session::wsSend(const std::string& message) {
     auto exec = stream_.get_executor();
     asio::post(exec, [self = shared_from_this(), message]() {
+        // P1-6：超过队列上限，判定慢消费者，关闭连接防内存耗尽
+        if (self->ws_send_queue_.size() >= self->server_->getMaxWsQueueSize()) {
+            std::cerr << "[WS] ws_send_queue_ overflow (" << self->ws_send_queue_.size()
+                      << " >= " << self->server_->getMaxWsQueueSize()
+                      << ") from " << self->getRemoteAddress() << ", closing" << std::endl;
+            self->close();
+            return;
+        }
         self->ws_send_queue_.push_back(message);
         if (self->ws_send_queue_.size() == 1) {
             self->doWsWrite();
@@ -373,6 +381,13 @@ void HttpServer::Session::onProxyReadClient(beast::error_code ec, std::size_t by
     // Queue to backend
     auto exec = stream_.get_executor();
     asio::post(exec, [self = shared_from_this(), data = std::move(data), is_binary]() {
+        // P1-6：超过队列上限，判定慢后端，关闭代理连接防内存耗尽
+        if (self->proxy_to_backend_queue_.size() >= self->server_->getMaxWsQueueSize()) {
+            std::cerr << "[WS-Proxy] proxy_to_backend_queue_ overflow ("
+                      << self->proxy_to_backend_queue_.size() << ") closing" << std::endl;
+            self->closeProxy(websocket::close_code::internal_error);
+            return;
+        }
         self->proxy_to_backend_queue_.emplace_back(std::move(data), is_binary);
         if (self->proxy_to_backend_queue_.size() == 1) {
             self->doProxyWriteBackend();
@@ -449,6 +464,13 @@ void HttpServer::Session::onProxyReadBackend(beast::error_code ec, std::size_t b
     // Queue to client
     auto exec = stream_.get_executor();
     asio::post(exec, [self = shared_from_this(), data = std::move(data), is_binary]() {
+        // P1-6：超过队列上限，判定慢客户端，关闭代理连接防内存耗尽
+        if (self->proxy_to_client_queue_.size() >= self->server_->getMaxWsQueueSize()) {
+            std::cerr << "[WS-Proxy] proxy_to_client_queue_ overflow ("
+                      << self->proxy_to_client_queue_.size() << ") closing" << std::endl;
+            self->closeProxy(websocket::close_code::internal_error);
+            return;
+        }
         self->proxy_to_client_queue_.emplace_back(std::move(data), is_binary);
         if (self->proxy_to_client_queue_.size() == 1) {
             self->doProxyWriteClient();