res_http_websocket: Avoid passing strlen() to ast_websocket_write().
[asterisk/asterisk.git] / res / res_pjsip_transport_websocket.c
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2013, Digium, Inc.
5  *
6  * Jason Parker <jparker@digium.com>
7  *
8  * See http://www.asterisk.org for more information about
9  * the Asterisk project. Please do not directly contact
10  * any of the maintainers of this project for assistance;
11  * the project provides a web site, mailing lists and IRC
12  * channels for your use.
13  *
14  * This program is free software, distributed under the terms of
15  * the GNU General Public License Version 2. See the LICENSE file
16  * at the top of the source tree.
17  */
18
19 /*!
20  * \brief WebSocket transport module
21  */
22
23 /*** MODULEINFO
24         <depend>pjproject</depend>
25         <depend>res_pjsip</depend>
26         <depend>res_http_websocket</depend>
27         <support_level>core</support_level>
28  ***/
29
30 #include "asterisk.h"
31
32 #include <pjsip.h>
33 #include <pjsip_ua.h>
34
35 #include "asterisk/module.h"
36 #include "asterisk/http_websocket.h"
37 #include "asterisk/res_pjsip.h"
38 #include "asterisk/res_pjsip_session.h"
39 #include "asterisk/taskprocessor.h"
40
41 static int transport_type_ws;
42 static int transport_type_wss;
43
44 /*!
45  * \brief Wrapper for pjsip_transport, for storing the WebSocket session
46  */
47 struct ws_transport {
48         pjsip_transport transport;
49         pjsip_rx_data rdata;
50         struct ast_websocket *ws_session;
51 };
52
53 /*!
54  * \brief Send a message over the WebSocket connection.
55  *
56  * Called by pjsip transport manager.
57  */
58 static pj_status_t ws_send_msg(pjsip_transport *transport,
59                             pjsip_tx_data *tdata,
60                             const pj_sockaddr_t *rem_addr,
61                             int addr_len,
62                             void *token,
63                             pjsip_transport_callback callback)
64 {
65         struct ws_transport *wstransport = (struct ws_transport *)transport;
66         uint64_t len = tdata->buf.cur - tdata->buf.start;
67
68         if (ast_websocket_write(wstransport->ws_session, AST_WEBSOCKET_OPCODE_TEXT, tdata->buf.start, len)) {
69                 return PJ_EUNKNOWN;
70         }
71
72         return PJ_SUCCESS;
73 }
74
75 /*!
76  * \brief Destroy the pjsip transport.
77  *
78  * Called by pjsip transport manager.
79  */
80 static pj_status_t ws_destroy(pjsip_transport *transport)
81 {
82         struct ws_transport *wstransport = (struct ws_transport *)transport;
83         int fd = ast_websocket_fd(wstransport->ws_session);
84
85         if (fd > 0) {
86                 ast_websocket_close(wstransport->ws_session, 1000);
87                 shutdown(fd, SHUT_RDWR);
88         }
89
90         ao2_ref(wstransport, -1);
91
92         return PJ_SUCCESS;
93 }
94
95 static void transport_dtor(void *arg)
96 {
97         struct ws_transport *wstransport = arg;
98
99         if (wstransport->ws_session) {
100                 ast_websocket_unref(wstransport->ws_session);
101         }
102
103         if (wstransport->transport.ref_cnt) {
104                 pj_atomic_destroy(wstransport->transport.ref_cnt);
105         }
106
107         if (wstransport->transport.lock) {
108                 pj_lock_destroy(wstransport->transport.lock);
109         }
110
111         if (wstransport->transport.endpt && wstransport->transport.pool) {
112                 pjsip_endpt_release_pool(wstransport->transport.endpt, wstransport->transport.pool);
113         }
114
115         if (wstransport->rdata.tp_info.pool) {
116                 pjsip_endpt_release_pool(wstransport->transport.endpt, wstransport->rdata.tp_info.pool);
117         }
118 }
119
120 static int transport_shutdown(void *data)
121 {
122         struct ws_transport *wstransport = data;
123
124         if (!wstransport->transport.is_shutdown && !wstransport->transport.is_destroying) {
125                 pjsip_transport_shutdown(&wstransport->transport);
126         }
127
128         /* Note that the destructor calls PJSIP functions,
129          * therefore it must be called in a PJSIP thread.
130          */
131         ao2_ref(wstransport, -1);
132
133         return 0;
134 }
135
136 struct transport_create_data {
137         struct ws_transport *transport;
138         struct ast_websocket *ws_session;
139 };
140
141 /*!
142  * \brief Create a pjsip transport.
143  */
144 static int transport_create(void *data)
145 {
146         struct transport_create_data *create_data = data;
147         struct ws_transport *newtransport = NULL;
148
149         pjsip_endpoint *endpt = ast_sip_get_pjsip_endpoint();
150         struct pjsip_tpmgr *tpmgr = pjsip_endpt_get_tpmgr(endpt);
151
152         pj_pool_t *pool;
153         pj_str_t buf;
154         pj_status_t status;
155
156         newtransport = ao2_t_alloc_options(sizeof(*newtransport), transport_dtor,
157                         AO2_ALLOC_OPT_LOCK_NOLOCK, "pjsip websocket transport");
158         if (!newtransport) {
159                 ast_log(LOG_ERROR, "Failed to allocate WebSocket transport.\n");
160                 goto on_error;
161         }
162
163         newtransport->transport.endpt = endpt;
164
165         if (!(pool = pjsip_endpt_create_pool(endpt, "ws", 512, 512))) {
166                 ast_log(LOG_ERROR, "Failed to allocate WebSocket endpoint pool.\n");
167                 goto on_error;
168         }
169
170         newtransport->transport.pool = pool;
171         newtransport->ws_session = create_data->ws_session;
172
173         /* Keep the session until transport dies */
174         ast_websocket_ref(newtransport->ws_session);
175
176         status = pj_atomic_create(pool, 0, &newtransport->transport.ref_cnt);
177         if (status != PJ_SUCCESS) {
178                 goto on_error;
179         }
180
181         status = pj_lock_create_recursive_mutex(pool, pool->obj_name, &newtransport->transport.lock);
182         if (status != PJ_SUCCESS) {
183                 goto on_error;
184         }
185
186         pj_sockaddr_parse(pj_AF_UNSPEC(), 0, pj_cstr(&buf, ast_sockaddr_stringify(ast_websocket_remote_address(newtransport->ws_session))), &newtransport->transport.key.rem_addr);
187         newtransport->transport.key.rem_addr.addr.sa_family = pj_AF_INET();
188         newtransport->transport.key.type = ast_websocket_is_secure(newtransport->ws_session) ? transport_type_wss : transport_type_ws;
189
190         newtransport->transport.addr_len = pj_sockaddr_get_len(&newtransport->transport.key.rem_addr);
191
192         pj_sockaddr_cp(&newtransport->transport.local_addr, &newtransport->transport.key.rem_addr);
193
194         newtransport->transport.local_name.host.ptr = (char *)pj_pool_alloc(pool, newtransport->transport.addr_len+4);
195         pj_sockaddr_print(&newtransport->transport.key.rem_addr, newtransport->transport.local_name.host.ptr, newtransport->transport.addr_len+4, 0);
196         newtransport->transport.local_name.host.slen = pj_ansi_strlen(newtransport->transport.local_name.host.ptr);
197         newtransport->transport.local_name.port = pj_sockaddr_get_port(&newtransport->transport.key.rem_addr);
198
199         newtransport->transport.type_name = (char *)pjsip_transport_get_type_name(newtransport->transport.key.type);
200         newtransport->transport.flag = pjsip_transport_get_flag_from_type((pjsip_transport_type_e)newtransport->transport.key.type);
201         newtransport->transport.info = (char *)pj_pool_alloc(newtransport->transport.pool, 64);
202
203         newtransport->transport.tpmgr = tpmgr;
204         newtransport->transport.send_msg = &ws_send_msg;
205         newtransport->transport.destroy = &ws_destroy;
206
207         status = pjsip_transport_register(newtransport->transport.tpmgr,
208                         (pjsip_transport *)newtransport);
209         if (status != PJ_SUCCESS) {
210                 goto on_error;
211         }
212
213         /* Add a reference for pjsip transport manager */
214         ao2_ref(newtransport, +1);
215
216         newtransport->rdata.tp_info.transport = &newtransport->transport;
217         newtransport->rdata.tp_info.pool = pjsip_endpt_create_pool(endpt, "rtd%p",
218                 PJSIP_POOL_RDATA_LEN, PJSIP_POOL_RDATA_INC);
219         if (!newtransport->rdata.tp_info.pool) {
220                 ast_log(LOG_ERROR, "Failed to allocate WebSocket rdata.\n");
221                 pjsip_transport_destroy((pjsip_transport *)newtransport);
222                 goto on_error;
223         }
224
225         create_data->transport = newtransport;
226         return 0;
227
228 on_error:
229         ao2_cleanup(newtransport);
230         return -1;
231 }
232
233 struct transport_read_data {
234         struct ws_transport *transport;
235         char *payload;
236         uint64_t payload_len;
237 };
238
239 /*!
240  * \brief Pass WebSocket data into pjsip transport manager.
241  */
242 static int transport_read(void *data)
243 {
244         struct transport_read_data *read_data = data;
245         struct ws_transport *newtransport = read_data->transport;
246         struct ast_websocket *session = newtransport->ws_session;
247
248         pjsip_rx_data *rdata = &newtransport->rdata;
249         int recvd;
250         pj_str_t buf;
251         int pjsip_pkt_len;
252
253         pj_gettimeofday(&rdata->pkt_info.timestamp);
254
255         pjsip_pkt_len = PJSIP_MAX_PKT_LEN < read_data->payload_len ? PJSIP_MAX_PKT_LEN : read_data->payload_len;
256         pj_memcpy(rdata->pkt_info.packet, read_data->payload, pjsip_pkt_len);
257         rdata->pkt_info.len = pjsip_pkt_len;
258         rdata->pkt_info.zero = 0;
259
260         pj_sockaddr_parse(pj_AF_UNSPEC(), 0, pj_cstr(&buf, ast_sockaddr_stringify(ast_websocket_remote_address(session))), &rdata->pkt_info.src_addr);
261         rdata->pkt_info.src_addr.addr.sa_family = pj_AF_INET();
262
263         rdata->pkt_info.src_addr_len = sizeof(rdata->pkt_info.src_addr);
264
265         pj_ansi_strcpy(rdata->pkt_info.src_name, ast_sockaddr_stringify_host(ast_websocket_remote_address(session)));
266         rdata->pkt_info.src_port = ast_sockaddr_port(ast_websocket_remote_address(session));
267
268         recvd = pjsip_tpmgr_receive_packet(rdata->tp_info.transport->tpmgr, rdata);
269
270         pj_pool_reset(rdata->tp_info.pool);
271
272         return (read_data->payload_len == recvd) ? 0 : -1;
273 }
274
275 static int get_write_timeout(void)
276 {
277         int write_timeout = -1;
278         struct ao2_container *transports;
279
280         transports = ast_sorcery_retrieve_by_fields(ast_sip_get_sorcery(), "transport", AST_RETRIEVE_FLAG_ALL, NULL);
281
282         if (transports) {
283                 struct ao2_iterator it_transports = ao2_iterator_init(transports, 0);
284                 struct ast_sip_transport *transport;
285
286                 for (; (transport = ao2_iterator_next(&it_transports)); ao2_cleanup(transport)) {
287                         if (transport->type != AST_TRANSPORT_WS && transport->type != AST_TRANSPORT_WSS) {
288                                 continue;
289                         }
290                         ast_debug(5, "Found %s transport with write timeout: %d\n",
291                                 transport->type == AST_TRANSPORT_WS ? "WS" : "WSS",
292                                 transport->write_timeout);
293                         write_timeout = MAX(write_timeout, transport->write_timeout);
294                 }
295                 ao2_cleanup(transports);
296         }
297
298         if (write_timeout < 0) {
299                 write_timeout = AST_DEFAULT_WEBSOCKET_WRITE_TIMEOUT;
300         }
301
302         ast_debug(1, "Write timeout for WS/WSS transports: %d\n", write_timeout);
303         return write_timeout;
304 }
305
306 /*!
307  \brief WebSocket connection handler.
308  */
309 static void websocket_cb(struct ast_websocket *session, struct ast_variable *parameters, struct ast_variable *headers)
310 {
311         struct ast_taskprocessor *serializer = NULL;
312         struct transport_create_data create_data;
313         struct ws_transport *transport = NULL;
314         struct transport_read_data read_data;
315
316         if (ast_websocket_set_nonblock(session)) {
317                 ast_websocket_unref(session);
318                 return;
319         }
320
321         if (ast_websocket_set_timeout(session, get_write_timeout())) {
322                 ast_websocket_unref(session);
323                 return;
324         }
325
326         if (!(serializer = ast_sip_create_serializer())) {
327                 ast_websocket_unref(session);
328                 return;
329         }
330
331         create_data.ws_session = session;
332
333         if (ast_sip_push_task_synchronous(serializer, transport_create, &create_data)) {
334                 ast_log(LOG_ERROR, "Could not create WebSocket transport.\n");
335                 ast_websocket_unref(session);
336                 return;
337         }
338
339         transport = create_data.transport;
340         read_data.transport = transport;
341
342         while (ast_wait_for_input(ast_websocket_fd(session), -1) > 0) {
343                 enum ast_websocket_opcode opcode;
344                 int fragmented;
345
346                 if (ast_websocket_read(session, &read_data.payload, &read_data.payload_len, &opcode, &fragmented)) {
347                         break;
348                 }
349
350                 if (opcode == AST_WEBSOCKET_OPCODE_TEXT || opcode == AST_WEBSOCKET_OPCODE_BINARY) {
351                         ast_sip_push_task_synchronous(serializer, transport_read, &read_data);
352                 } else if (opcode == AST_WEBSOCKET_OPCODE_CLOSE) {
353                         break;
354                 }
355         }
356
357         ast_sip_push_task_synchronous(serializer, transport_shutdown, transport);
358
359         ast_taskprocessor_unreference(serializer);
360         ast_websocket_unref(session);
361 }
362
363 /*!
364  * \brief Store the transport a message came in on, so it can be used for outbound messages to that contact.
365  */
366 static pj_bool_t websocket_on_rx_msg(pjsip_rx_data *rdata)
367 {
368         static const pj_str_t STR_WS = { "ws", 2 };
369         static const pj_str_t STR_WSS = { "wss", 3 };
370         pjsip_contact_hdr *contact;
371
372         long type = rdata->tp_info.transport->key.type;
373
374         if (type != (long)transport_type_ws && type != (long)transport_type_wss) {
375                 return PJ_FALSE;
376         }
377
378         if ((contact = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CONTACT, NULL)) && !contact->star &&
379                 (PJSIP_URI_SCHEME_IS_SIP(contact->uri) || PJSIP_URI_SCHEME_IS_SIPS(contact->uri))) {
380                 pjsip_sip_uri *uri = pjsip_uri_get_uri(contact->uri);
381
382                 pj_cstr(&uri->host, rdata->pkt_info.src_name);
383                 uri->port = rdata->pkt_info.src_port;
384                 ast_debug(4, "Re-wrote Contact URI host/port to %.*s:%d\n",
385                         (int)pj_strlen(&uri->host), pj_strbuf(&uri->host), uri->port);
386                 pj_strdup(rdata->tp_info.pool, &uri->transport_param, (type == (long)transport_type_ws) ? &STR_WS : &STR_WSS);
387         }
388
389         rdata->msg_info.via->rport_param = 0;
390
391         return PJ_FALSE;
392 }
393
394 static pjsip_module websocket_module = {
395         .name = { "WebSocket Transport Module", 26 },
396         .id = -1,
397         .priority = PJSIP_MOD_PRIORITY_TRANSPORT_LAYER,
398         .on_rx_request = websocket_on_rx_msg,
399         .on_rx_response = websocket_on_rx_msg,
400 };
401
402 /*! \brief Function called when an INVITE goes out */
403 static void websocket_outgoing_invite_request(struct ast_sip_session *session, struct pjsip_tx_data *tdata)
404 {
405         if (session->inv_session->state == PJSIP_INV_STATE_NULL) {
406                 pjsip_dlg_add_usage(session->inv_session->dlg, &websocket_module, NULL);
407         }
408 }
409
410 /*! \brief Supplement for adding Websocket functionality to dialog */
411 static struct ast_sip_session_supplement websocket_supplement = {
412         .method = "INVITE",
413         .priority = AST_SIP_SUPPLEMENT_PRIORITY_FIRST + 1,
414         .outgoing_request = websocket_outgoing_invite_request,
415 };
416
417 static int load_module(void)
418 {
419         CHECK_PJSIP_MODULE_LOADED();
420
421         pjsip_transport_register_type(PJSIP_TRANSPORT_RELIABLE, "WS", 5060, &transport_type_ws);
422         pjsip_transport_register_type(PJSIP_TRANSPORT_RELIABLE, "WSS", 5060, &transport_type_wss);
423
424         if (ast_sip_register_service(&websocket_module) != PJ_SUCCESS) {
425                 return AST_MODULE_LOAD_DECLINE;
426         }
427
428         if (ast_sip_session_register_supplement(&websocket_supplement)) {
429                 ast_sip_unregister_service(&websocket_module);
430                 return AST_MODULE_LOAD_DECLINE;
431         }
432
433         if (ast_websocket_add_protocol("sip", websocket_cb)) {
434                 ast_sip_session_unregister_supplement(&websocket_supplement);
435                 ast_sip_unregister_service(&websocket_module);
436                 return AST_MODULE_LOAD_DECLINE;
437         }
438
439         return AST_MODULE_LOAD_SUCCESS;
440 }
441
442 static int unload_module(void)
443 {
444         ast_sip_unregister_service(&websocket_module);
445         ast_sip_session_unregister_supplement(&websocket_supplement);
446         ast_websocket_remove_protocol("sip", websocket_cb);
447
448         return 0;
449 }
450
451 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP WebSocket Transport Support",
452         .support_level = AST_MODULE_SUPPORT_CORE,
453         .load = load_module,
454         .unload = unload_module,
455         .load_pri = AST_MODPRI_APP_DEPEND,
456 );