Websocket：C-服务器 --> 浏览器无效帧头

Question

亲爱的 stackoverflow 论坛，

我的 C 服务器和客户端 (javascript) 之间的通信存在问题。我使用 Rasperry Pi 4 作为服务器，Chrome 作为浏览器（我还使用 Firefox 和 Edge 测试了我的东西）。

我的问题是握手的帧头是什么样的。握手应将通信协议从 HTTP 更改为 websocket。我的标题看起来像这样：

GET / HTTP/1.1
Host: 192.168.1.100:8000
Connection: Upgrade
Pragma: no-cache
Cache-Control: no-cache
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko)
Chrome/119.0.0.0 Safari/537.36
Upgrade: websocket
Origin: http://192.168.1.100
Sec-WebSocket-Version: 13
Accept-Encoding: gzip, deflate
Accept-Language: de-DE,de;q=0.9,en-US;q=0.8,en;q=0.7
Sec-WebSocket-Key: 6Hw/S8rXFY4ExVDMGWWn6Q==
Sec-WebSocket-Extensions: permessage-deflate; client_max_window_bits

服务器端的回答（附生成响应请求的代码）：

HTTP/1.1 101 Switching Protocols
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Accept: 57dCnQc8YJrJ51osdI/I71QHYi4=

现在我在浏览器中收到消息：

script.js:8 WebSocket connection to 'ws://192.168.1.100:8000/' failed: Invalid frame header.

在wireshark中，我可以看到帧头看起来与上面的完全一样。浏览器（客户端）以红色突出显示的消息进行响应：响应中设置了重置标志。

有人看到帧头中有错误吗？或者哈希码可能是错误的？

图比

Answer 1

我找到了一个解决方案，我对传入数据的处理错误。数据必须像这样解码：

int rxDataLen = 0;
char rxBuf[rxBufferSize];
char selectedObject;
int16_t controlledValue;
WH_Status_t ret = OK;
uint8_t k = 0;

char rxBuf[rxBufferSize];
int rx_data_len = recv (comSockId, (void *)rxBuf, rxBufferSize, MSG_DONTWAIT);
        // Has a new WebSocket message have been received
        if (rx_data_len > 0) {
            rxBuf[rx_data_len] = '\0';
            // Is the message a handshake request
            if (strncmp(rxBuf, "GET", 3) == 0) {
                printf("%s\n", rxBuf);
                // Yes -> create the handshake response and send it back
                char response[WS_HS_ACCLEN];
                get_handshake_response(rxBuf, response);
                send(comSockId, (void *)response, strlen(response), 0);
                printf("Handshake done\n");
            }
            else {
                /* No -> decode incoming message,
                process the command and
                send back an acknowledge message */
                char command[rx_data_len];
                decode_incoming_request(rxBuf, command);
                command[strlen(command)] = '\0';

                /* Check, if the website has been closed. */
                if (strncmp(command, "close", 5) == 0){
                    printf("Cliend closed connection.\n");
                    return closeClient;
                }

                // Decode the message string to control the webhouse.
                analyseMessage((char*)&command, &selectedObject, &controlledValue);

                char response[6] = {0};
                sendMessage((char*)&(response), &selectedObject, actualTemperature, alarmState);
                printf("Answer: %s\n", response);
                char codedResponse[strlen(response)+1];
                code_outgoing_response (response, codedResponse);
                send(comSockId, (void *)codedResponse,
                strlen(codedResponse), 0);
            }
        }

当连接处于活动状态时，您必须循环执行此代码行，直到连接关闭或从服务器端关闭它。这样，就不再存在无效的帧头。