fix: improve memory management and error handling in WebSocket and HTTP2 implementations

.gitignore

@@ -59,3 +59,4 @@ ssl/*
 src/bin
 docker-push.sh
 .idea
+error.txt

src/http2.c

@@ -258,6 +258,8 @@ static int on_frame_recv_callback(nghttp2_session* session,
                 {
                     close(fd);
                     free(mime_type);
+                    stream_data->mime_type = NULL;  // Prevent double-free in cleanup
+                    stream_data->fd = -1;           // Mark fd as already closed
                     log_event("HTTP/2: Memory allocation failed");
                     break;
                 }
@@ -403,8 +405,12 @@ static int on_begin_headers_callback(nghttp2_session* session,
     stream_data->stream_id = frame->hd.stream_id;
     stream_data->fd = -1;
 
-    nghttp2_session_set_stream_user_data(session, frame->hd.stream_id, stream_data);
+    if (nghttp2_session_set_stream_user_data(session, frame->hd.stream_id, stream_data) != 0)
+    {
         free(stream_data);
+        return NGHTTP2_ERR_CALLBACK_FAILURE;
+    }
+
     return 0;
 }
 

src/server.c

@@ -528,12 +528,11 @@ static int is_websocket_upgrade(const char* request)
 // Handle WebSocket connection
 static void* handle_websocket(void* arg)
 {
-    ws_connection_t* conn = (ws_connection_t*)arg;
+    ws_connection_t* conn = arg;
 
-
-    // Remove socket timeout for WebSocket (connections should stay open)
+    // Remove socket timeout for WebSocket
     struct timeval ws_timeout;
-    ws_timeout.tv_sec = 0; // No timeout - wait indefinitely
+    ws_timeout.tv_sec = 0;
     ws_timeout.tv_usec = 0;
     setsockopt(conn->socket_fd, SOL_SOCKET, SO_RCVTIMEO, &ws_timeout, sizeof(ws_timeout));
 
@@ -571,18 +570,19 @@ static void* handle_websocket(void* arg)
         if (parsed < 0)
         {
             log_event("Failed to parse WebSocket frame");
-            free(payload);
+            free(payload);  // Safe - only frees if allocated
             ws_close_connection(conn, 1002);
             free(conn);
             pthread_exit(NULL);
         }
 
+        bool should_exit = false;
+
         switch (header.opcode)
         {
         case WS_OPCODE_TEXT:
             if (ws_is_valid_utf8(payload, header.payload_length))
             {
-                // Echo back the text message
                 ws_send_frame(conn, WS_OPCODE_TEXT, payload, header.payload_length);
                 log_event("WebSocket text frame received and echoed");
             }
@@ -593,7 +593,6 @@ static void* handle_websocket(void* arg)
             break;
 
         case WS_OPCODE_BINARY:
-            // Echo back binary data
             ws_send_frame(conn, WS_OPCODE_BINARY, payload, header.payload_length);
             log_event("WebSocket binary frame received and echoed");
             break;
@@ -605,16 +604,22 @@ static void* handle_websocket(void* arg)
 
         case WS_OPCODE_CLOSE:
             log_event("WebSocket close frame received");
-            free(payload);
-            ws_close_connection(conn, 1000);
-            free(conn);
-            pthread_exit(NULL);
+            should_exit = true;
+            break;
 
         default:
             break;
         }
 
         free(payload);
+        payload = NULL;
+
+        if (should_exit)
+        {
+            ws_close_connection(conn, 1000);
+            free(conn);
+            pthread_exit(NULL);
+        }
     }
 
     ws_close_connection(conn, 1000);
@@ -622,6 +627,7 @@ static void* handle_websocket(void* arg)
     pthread_exit(NULL);
 }
 
+
 void* handle_http_client(void* arg)
 {
     int client_socket = *((int*)arg);
@@ -1066,7 +1072,7 @@ void* handle_http_client(void* arg)
         done_serving:
             continue;
         }
-        else if (bytes_received < 0)
+        if (bytes_received < 0)
         {
             break;
         }
@@ -1081,7 +1087,7 @@ cleanup:
 
 void* handle_https_client(void* arg)
 {
-    int client_socket = *((int*)arg);
+    int client_socket = *(int*)arg;
     free(arg);
 
     SSL* ssl = SSL_new(ssl_ctx);
@@ -1176,17 +1182,14 @@ void* handle_https_client(void* arg)
         log_event("SSL_read failed");
         goto cleanup;
     }
-    else if (bytes_received == 0)
+    if (bytes_received == 0)
     {
         log_event("Client closed connection");
         goto cleanup;
     }
-    else
-    {
     buffer[bytes_received] = '\0';
     log_event("Received HTTPS request:");
     log_event(buffer);
-    }
 
     // Check for WebSocket upgrade request on HTTPS
     if (config.enable_websocket && is_websocket_upgrade(buffer))
@@ -1220,20 +1223,14 @@ void* handle_https_client(void* arg)
                 handle_websocket(ws_conn);
                 pthread_exit(NULL);
             }
-            else
-            {
             SSL_shutdown(ssl);
             SSL_free(ssl);
             close(client_socket);
             pthread_exit(NULL);
         }
-        }
-        else
-        {
         log_event("Secure WebSocket handshake failed");
         goto cleanup;
     }
-    }
 
     char method[8], url[256], protocol[16];
     if (parse_request_line(buffer, method, url, protocol) != 0)
@@ -1791,7 +1788,6 @@ void* worker_thread(void* arg)
                 *socket_ptr = task->socket_fd;
                 handle_https_client(socket_ptr);
             }
-            free(socket_ptr);
         }
         else
         {

src/websocket.c

@@ -111,7 +111,7 @@ int ws_handle_handshake(int client_socket, const char* request, char* response,
     }
 
     // Create handshake response
-    int written = snprintf(response, response_size,
+    const int written = snprintf(response, response_size,
                            "HTTP/1.1 101 Switching Protocols\r\n"
                            "Upgrade: websocket\r\n"
                            "Connection: Upgrade\r\n"
@@ -125,34 +125,39 @@ int ws_handle_handshake(int client_socket, const char* request, char* response,
     {
         return -1;
     }
-
     return 0;
 }
 
 // Handle WebSocket handshake for SSL connections
-int ws_handle_handshake_ssl(SSL* ssl, const char* request, char* response, size_t response_size)
+int ws_handle_handshake_ssl(const SSL* ssl, const char* request, char* response, const size_t response_size)
 {
     (void)ssl; // Use the same logic, just different transport
     return ws_handle_handshake(0, request, response, response_size);
 }
 
+void ws_free_payload(uint8_t* payload)
+{
+    if (payload)
+    {
+        free(payload);
+    }
+}
+
 // Parse WebSocket frame
-int ws_parse_frame(const uint8_t* data, size_t len, ws_frame_header_t* header, uint8_t** payload)
+int ws_parse_frame(const uint8_t* data, const size_t len, ws_frame_header_t* header, uint8_t** payload)
 {
     // Maximum allowed WebSocket payload size (10MB)
 #define MAX_WEBSOCKET_PAYLOAD (10 * 1024 * 1024)
 
     if (len < 2)
-    {
         return -1;
-    }
 
     header->fin = (data[0] & 0x80) >> 7;
     header->opcode = data[0] & 0x0F;
     header->mask = (data[1] & 0x80) >> 7;
 
     size_t offset = 2;
-    uint8_t payload_len = data[1] & 0x7F;
+    const uint8_t payload_len = data[1] & 0x7F;
 
     if (payload_len == 126)
     {
@@ -177,10 +182,7 @@ int ws_parse_frame(const uint8_t* data, size_t len, ws_frame_header_t* header, u
         header->payload_length = payload_len;
     }
 
-    if (header->payload_length > MAX_WEBSOCKET_PAYLOAD)
-    {
-        return -1;
-    }
+    if (header->payload_length > MAX_WEBSOCKET_PAYLOAD) return -1;
 
     if (header->mask)
     {
@@ -195,11 +197,13 @@ int ws_parse_frame(const uint8_t* data, size_t len, ws_frame_header_t* header, u
         return -1;
     }
 
-    // Unmask payload if masked
-    *payload = (uint8_t*)malloc(header->payload_length);
+    // Allocate payload buffer if there is payload data
+    if (header->payload_length > 0)
+    {
+        *payload = malloc(header->payload_length);
         if (!*payload)
         {
-        return -1;
+            return -1;  // Allocation failed
         }
 
         if (header->mask)
@@ -213,12 +217,13 @@ int ws_parse_frame(const uint8_t* data, size_t len, ws_frame_header_t* header, u
         {
             memcpy(*payload, data + offset, header->payload_length);
         }
+    }
 
     return offset + header->payload_length;
 }
 
 // Create WebSocket frame
-int ws_create_frame(uint8_t* buffer, size_t buffer_size, uint8_t opcode, const uint8_t* payload, size_t payload_len)
+int ws_create_frame(uint8_t* buffer,const size_t buffer_size,const uint8_t opcode, const uint8_t* payload, size_t payload_len)
 {
     size_t header_size;
 
@@ -276,9 +281,69 @@ int ws_create_frame(uint8_t* buffer, size_t buffer_size, uint8_t opcode, const u
 
     return (int)offset;
 }
+int ws_send_frame_chunk(const ws_connection_t* conn,const uint8_t opcode,const uint8_t fin, const uint8_t* payload,const size_t payload_len) {
+    uint8_t buffer[65536];
+    size_t header_size;
+    size_t offset = 0;
 
+    if (payload_len < 126) {
+        header_size = 2;
+    } else if (payload_len < 65536) {
+        header_size = 4;
+    } else {
+        header_size = 10;
+    }
+
+    if (header_size + payload_len >sizeof(buffer)) return -1;
+
+    buffer[offset++] = (fin ? 0x80 : 0x00) | (opcode & 0x0F);
+
+    if (payload_len < 126) {
+        buffer[offset++] = (uint8_t)payload_len;
+    } else if (payload_len < 65536) {
+        buffer[offset++] = 126;
+        buffer[offset++] = (payload_len >> 8) & 0xFF;
+        buffer[offset++] = payload_len & 0xFF;
+    } else {
+        buffer[offset++] = 127;
+        for (int i = 7; i >= 0; i--) {
+            buffer[offset++] = (payload_len >> (i * 8)) & 0xFF;
+        }
+    }
+
+    if (payload && payload_len > 0) {
+        memcpy(buffer + offset, payload, payload_len);
+        offset += payload_len;
+    }
+
+    ssize_t sent;
+    if (conn->is_ssl && conn->ssl) {
+        sent = SSL_write(conn->ssl, buffer, offset);
+    } else {
+        sent = write(conn->socket_fd, buffer, offset);
+    }
+
+    return (sent > 0) ? sent : -1;
+}
+
+int ws_send_frame_fragmented(const ws_connection_t* conn,const uint8_t opcode, const uint8_t* payload,const size_t payload_len) {
+    size_t offset = 0;
+
+    while (offset < payload_len) {
+        const size_t CHUNK_SIZE = 65526;
+        const size_t chunk = (payload_len - offset > CHUNK_SIZE) ? CHUNK_SIZE : (payload_len - offset);
+        const uint8_t frame_opcode = (offset == 0) ? opcode : WS_OPCODE_CONTINUATION;
+        const uint8_t fin = (offset + chunk >= payload_len) ? 0x80 : 0x00;
+
+        const int result = ws_send_frame_chunk(conn, frame_opcode, fin, payload + offset, chunk);
+
+        if (result < 0) return result;
+        offset += chunk;
+    }
+    return offset;
+}
 // Send WebSocket frame
-int ws_send_frame(ws_connection_t* conn, uint8_t opcode, const uint8_t* payload, size_t payload_len)
+int ws_send_frame(const ws_connection_t* conn, const uint8_t opcode, const uint8_t* payload, const size_t payload_len)
 {
     // Allocate buffer with enough space for header (max 10 bytes) + payload
     // Check for integer overflow
@@ -290,13 +355,15 @@ int ws_send_frame(ws_connection_t* conn, uint8_t opcode, const uint8_t* payload,
     uint8_t buffer[65536];
 
     // Limit payload to avoid overflow (65536 - 10 bytes for max header)
+
+    //TODO: Logging errors
     size_t safe_payload_len = payload_len;
     if (safe_payload_len > 65526)
     {
         safe_payload_len = 65526;
     }
 
-    int frame_len = ws_create_frame(buffer, sizeof(buffer), opcode, payload, safe_payload_len);
+    const int frame_len = ws_create_frame(buffer, sizeof(buffer), opcode, payload, safe_payload_len);
 
     if (frame_len < 0)
     {
@@ -307,10 +374,7 @@ int ws_send_frame(ws_connection_t* conn, uint8_t opcode, const uint8_t* payload,
     {
         return SSL_write(conn->ssl, buffer, frame_len);
     }
-    else
-    {
     return write(conn->socket_fd, buffer, frame_len);
-    }
 }
 
 // Send text message
@@ -326,7 +390,7 @@ int ws_send_pong(ws_connection_t* conn, const uint8_t* payload, size_t payload_l
 }
 
 // Close WebSocket connection
-void ws_close_connection(ws_connection_t* conn, uint16_t status_code)
+void ws_close_connection(ws_connection_t* conn, const uint16_t status_code)
 {
     uint8_t close_payload[2];
     close_payload[0] = (status_code >> 8) & 0xFF;
@@ -338,12 +402,14 @@ void ws_close_connection(ws_connection_t* conn, uint16_t status_code)
     {
         SSL_shutdown(conn->ssl);
         SSL_free(conn->ssl);
+        conn->ssl = NULL;  // Prevent double-free
     }
     close(conn->socket_fd);
+    conn->socket_fd = -1;  // Mark as closed
 }
 
 // Validate UTF-8 encoding
-bool ws_is_valid_utf8(const uint8_t* data, size_t len)
+bool ws_is_valid_utf8(const uint8_t* data, const size_t len)
 {
     size_t i = 0;
     while (i < len)

src/websocket.h

@@ -34,10 +34,10 @@ typedef struct
 
 // Function prototypes
 int ws_handle_handshake(int client_socket, const char* request, char* response, size_t response_size);
-int ws_handle_handshake_ssl(SSL* ssl, const char* request, char* response, size_t response_size);
+int ws_handle_handshake_ssl(const SSL* ssl, const char* request, char* response, size_t response_size);
 int ws_parse_frame(const uint8_t* data, size_t len, ws_frame_header_t* header, uint8_t** payload);
 int ws_create_frame(uint8_t* buffer, size_t buffer_size, uint8_t opcode, const uint8_t* payload, size_t payload_len);
-int ws_send_frame(ws_connection_t* conn, uint8_t opcode, const uint8_t* payload, size_t payload_len);
+int ws_send_frame(const ws_connection_t* conn, uint8_t opcode, const uint8_t* payload, size_t payload_len);
 int ws_send_text(ws_connection_t* conn, const char* text);
 int ws_send_pong(ws_connection_t* conn, const uint8_t* payload, size_t payload_len);
 void ws_close_connection(ws_connection_t* conn, uint16_t status_code);