1 /** @file
2 * @brief Websocket API
3 *
4 * An API for applications to setup websocket connections
5 */
6
7 /*
8 * Copyright (c) 2019 Intel Corporation
9 *
10 * SPDX-License-Identifier: Apache-2.0
11 */
12
13 #ifndef ZEPHYR_INCLUDE_NET_WEBSOCKET_H_
14 #define ZEPHYR_INCLUDE_NET_WEBSOCKET_H_
15
16 #include <zephyr/kernel.h>
17
18 #include <zephyr/net/net_ip.h>
19 #include <zephyr/net/http/parser.h>
20 #include <zephyr/net/http/client.h>
21
22 #ifdef __cplusplus
23 extern "C" {
24 #endif
25
26 /**
27 * @brief Websocket API
28 * @defgroup websocket Websocket API
29 * @since 1.12
30 * @version 0.1.0
31 * @ingroup networking
32 * @{
33 */
34
35 /** Message type values. Returned in websocket_recv_msg() */
36 #define WEBSOCKET_FLAG_FINAL 0x00000001 /**< Final frame */
37 #define WEBSOCKET_FLAG_TEXT 0x00000002 /**< Textual data */
38 #define WEBSOCKET_FLAG_BINARY 0x00000004 /**< Binary data */
39 #define WEBSOCKET_FLAG_CLOSE 0x00000008 /**< Closing connection */
40 #define WEBSOCKET_FLAG_PING 0x00000010 /**< Ping message */
41 #define WEBSOCKET_FLAG_PONG 0x00000020 /**< Pong message */
42
43 /** @brief Websocket option codes */
44 enum websocket_opcode {
45 WEBSOCKET_OPCODE_CONTINUE = 0x00, /**< Message continues */
46 WEBSOCKET_OPCODE_DATA_TEXT = 0x01, /**< Textual data */
47 WEBSOCKET_OPCODE_DATA_BINARY = 0x02, /**< Binary data */
48 WEBSOCKET_OPCODE_CLOSE = 0x08, /**< Closing connection */
49 WEBSOCKET_OPCODE_PING = 0x09, /**< Ping message */
50 WEBSOCKET_OPCODE_PONG = 0x0A, /**< Pong message */
51 };
52
53 /**
54 * @typedef websocket_connect_cb_t
55 * @brief Callback called after Websocket connection is established.
56 *
57 * @param ws_sock Websocket id
58 * @param req HTTP handshake request
59 * @param user_data A valid pointer on some user data or NULL
60 *
61 * @return 0 if ok, <0 if there is an error and connection should be aborted
62 */
63 typedef int (*websocket_connect_cb_t)(int ws_sock, struct http_request *req,
64 void *user_data);
65
66 /**
67 * Websocket client connection request. This contains all the data that is
68 * needed when doing a Websocket connection request.
69 */
70 struct websocket_request {
71 /** Host of the Websocket server when doing HTTP handshakes. */
72 const char *host;
73
74 /** URL of the Websocket. */
75 const char *url;
76
77 /** User supplied callback function to call when optional headers need
78 * to be sent. This can be NULL, in which case the optional_headers
79 * field in http_request is used. The idea of this optional_headers
80 * callback is to allow user to send more HTTP header data that is
81 * practical to store in allocated memory.
82 */
83 http_header_cb_t optional_headers_cb;
84
85 /** A NULL terminated list of any optional headers that
86 * should be added to the HTTP request. May be NULL.
87 * If the optional_headers_cb is specified, then this field is ignored.
88 */
89 const char **optional_headers;
90
91 /** User supplied callback function to call when a connection is
92 * established.
93 */
94 websocket_connect_cb_t cb;
95
96 /** User supplied list of callback functions if the calling application
97 * wants to know the parsing status or the HTTP fields during the
98 * handshake. This is optional parameter and normally not needed but
99 * is useful if the caller wants to know something about
100 * the fields that the server is sending.
101 */
102 const struct http_parser_settings *http_cb;
103
104 /** User supplied buffer where HTTP connection data is stored */
105 uint8_t *tmp_buf;
106
107 /** Length of the user supplied temp buffer */
108 size_t tmp_buf_len;
109 };
110
111 /**
112 * @brief Connect to a server that provides Websocket service. The callback is
113 * called after connection is established. The returned value is a new socket
114 * descriptor that can be used to send / receive data using the BSD socket API.
115 *
116 * @param http_sock Socket id to the server. Note that this socket is used to do
117 * HTTP handshakes etc. The actual Websocket connectivity is done via the
118 * returned websocket id. Note that the http_sock must not be closed
119 * after this function returns as it is used to deliver the Websocket
120 * packets to the Websocket server.
121 * @param req Websocket request. User should allocate and fill the request
122 * data.
123 * @param timeout Max timeout to wait for the connection. The timeout value is
124 * in milliseconds. Value SYS_FOREVER_MS means to wait forever.
125 * @param user_data User specified data that is passed to the callback.
126 *
127 * @return Websocket id to be used when sending/receiving Websocket data.
128 */
129 int websocket_connect(int http_sock, struct websocket_request *req,
130 int32_t timeout, void *user_data);
131
132 /**
133 * @brief Send websocket msg to peer.
134 *
135 * @details The function will automatically add websocket header to the
136 * message.
137 *
138 * @param ws_sock Websocket id returned by websocket_connect().
139 * @param payload Websocket data to send.
140 * @param payload_len Length of the data to be sent.
141 * @param opcode Operation code (text, binary, ping, pong, close)
142 * @param mask Mask the data, see RFC 6455 for details
143 * @param final Is this final message for this message send. If final == false,
144 * then the first message must have valid opcode and subsequent messages
145 * must have opcode WEBSOCKET_OPCODE_CONTINUE. If final == true and this
146 * is the only message, then opcode should have proper opcode (text or
147 * binary) set.
148 * @param timeout How long to try to send the message. The value is in
149 * milliseconds. Value SYS_FOREVER_MS means to wait forever.
150 *
151 * @return <0 if error, >=0 amount of bytes sent
152 */
153 int websocket_send_msg(int ws_sock, const uint8_t *payload, size_t payload_len,
154 enum websocket_opcode opcode, bool mask, bool final,
155 int32_t timeout);
156
157 /**
158 * @brief Receive websocket msg from peer.
159 *
160 * @details The function will automatically remove websocket header from the
161 * message.
162 *
163 * @param ws_sock Websocket id returned by websocket_connect().
164 * @param buf Buffer where websocket data is read.
165 * @param buf_len Length of the data buffer.
166 * @param message_type Type of the message.
167 * @param remaining How much there is data left in the message after this read.
168 * @param timeout How long to try to receive the message.
169 * The value is in milliseconds. Value SYS_FOREVER_MS means to wait
170 * forever.
171 *
172 * @retval >=0 amount of bytes received.
173 * @retval -EAGAIN on timeout.
174 * @retval -ENOTCONN on socket close.
175 * @retval -errno other negative errno value in case of failure.
176 */
177 int websocket_recv_msg(int ws_sock, uint8_t *buf, size_t buf_len,
178 uint32_t *message_type, uint64_t *remaining,
179 int32_t timeout);
180
181 /**
182 * @brief Close websocket.
183 *
184 * @details One must call websocket_connect() after this call to re-establish
185 * the connection.
186 *
187 * @param ws_sock Websocket id returned by websocket_connect().
188 *
189 * @return <0 if error, 0 the connection was closed successfully
190 */
191 int websocket_disconnect(int ws_sock);
192
193 /**
194 * @brief Register a socket as websocket. This is called by HTTP server
195 * when a connection is upgraded to a websocket connection.
196 *
197 * @param http_sock Underlying socket connection socket.
198 * @param recv_buf Temporary receive buffer for websocket parsing. This must
199 * point to a memory area that is valid for the duration of the whole
200 * websocket session.
201 * @param recv_buf_len Length of the temporary receive buffer.
202 *
203 * @return <0 if error, >=0 the actual websocket to be used by application
204 */
205 int websocket_register(int http_sock, uint8_t *recv_buf, size_t recv_buf_len);
206
207 /**
208 * @brief Unregister a websocket. This is called when we no longer need
209 * the underlying "real" socket. This will close first the websocket
210 * and then the original socket.
211 *
212 * @param ws_sock Websocket connection socket.
213 *
214 * @return <0 if error, 0 the websocket connection is now fully closed
215 */
216 int websocket_unregister(int ws_sock);
217
218 /** @cond INTERNAL_HIDDEN */
219
220 #if defined(CONFIG_WEBSOCKET_CLIENT)
221 void websocket_init(void);
222 #else
websocket_init(void)223 static inline void websocket_init(void)
224 {
225 }
226 #endif
227
228 /** @endcond */
229
230 #ifdef __cplusplus
231 }
232 #endif
233
234 /**
235 * @}
236 */
237
238 #endif /* ZEPHYR_INCLUDE_NET_WEBSOCKET_H_ */
239
