a00299ebb3acb5379d23f22e0e3d707816df4dfa
[asterisk/asterisk.git] / res / res_pjsip_session.c
1 /*
2 * Asterisk -- An open source telephony toolkit.
3 *
4 * Copyright (C) 2013, Digium, Inc.
5 *
6 * Mark Michelson <mmichelson@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 /*** MODULEINFO
20         <depend>pjproject</depend>
21         <depend>res_pjsip</depend>
22         <support_level>core</support_level>
23  ***/
24
25 #include "asterisk.h"
26
27 #include <pjsip.h>
28 #include <pjsip_ua.h>
29 #include <pjlib.h>
30
31 #include "asterisk/res_pjsip.h"
32 #include "asterisk/res_pjsip_session.h"
33 #include "asterisk/datastore.h"
34 #include "asterisk/module.h"
35 #include "asterisk/logger.h"
36 #include "asterisk/res_pjsip.h"
37 #include "asterisk/astobj2.h"
38 #include "asterisk/lock.h"
39 #include "asterisk/uuid.h"
40 #include "asterisk/pbx.h"
41 #include "asterisk/taskprocessor.h"
42 #include "asterisk/causes.h"
43 #include "asterisk/sdp_srtp.h"
44 #include "asterisk/dsp.h"
45 #include "asterisk/acl.h"
46
47 #define SDP_HANDLER_BUCKETS 11
48
49 #define MOD_DATA_ON_RESPONSE "on_response"
50 #define MOD_DATA_NAT_HOOK "nat_hook"
51
52 /* Hostname used for origin line within SDP */
53 static const pj_str_t *hostname;
54
55 /* Some forward declarations */
56 static void handle_incoming_request(struct ast_sip_session *session, pjsip_rx_data *rdata);
57 static void handle_incoming_response(struct ast_sip_session *session, pjsip_rx_data *rdata);
58 static int handle_incoming(struct ast_sip_session *session, pjsip_rx_data *rdata);
59 static void handle_outgoing_request(struct ast_sip_session *session, pjsip_tx_data *tdata);
60 static void handle_outgoing_response(struct ast_sip_session *session, pjsip_tx_data *tdata);
61 static void handle_outgoing(struct ast_sip_session *session, pjsip_tx_data *tdata);
62
63 /*! \brief NAT hook for modifying outgoing messages with SDP */
64 static struct ast_sip_nat_hook *nat_hook;
65
66 /*!
67  * \brief Registered SDP stream handlers
68  *
69  * This container is keyed on stream types. Each
70  * object in the container is a linked list of
71  * handlers for the stream type.
72  */
73 static struct ao2_container *sdp_handlers;
74
75 /*!
76  * These are the objects in the sdp_handlers container
77  */
78 struct sdp_handler_list {
79         /* The list of handlers to visit */
80         AST_LIST_HEAD_NOLOCK(, ast_sip_session_sdp_handler) list;
81         /* The handlers in this list handle streams of this type */
82         char stream_type[1];
83 };
84
85 static struct pjmedia_sdp_session *create_local_sdp(pjsip_inv_session *inv, struct ast_sip_session *session, const pjmedia_sdp_session *offer);
86
87 static int sdp_handler_list_hash(const void *obj, int flags)
88 {
89         const struct sdp_handler_list *handler_list = obj;
90         const char *stream_type = flags & OBJ_KEY ? obj : handler_list->stream_type;
91
92         return ast_str_hash(stream_type);
93 }
94
95 static int sdp_handler_list_cmp(void *obj, void *arg, int flags)
96 {
97         struct sdp_handler_list *handler_list1 = obj;
98         struct sdp_handler_list *handler_list2 = arg;
99         const char *stream_type2 = flags & OBJ_KEY ? arg : handler_list2->stream_type;
100
101         return strcmp(handler_list1->stream_type, stream_type2) ? 0 : CMP_MATCH | CMP_STOP;
102 }
103
104 static int session_media_hash(const void *obj, int flags)
105 {
106         const struct ast_sip_session_media *session_media = obj;
107         const char *stream_type = flags & OBJ_KEY ? obj : session_media->stream_type;
108
109         return ast_str_hash(stream_type);
110 }
111
112 static int session_media_cmp(void *obj, void *arg, int flags)
113 {
114         struct ast_sip_session_media *session_media1 = obj;
115         struct ast_sip_session_media *session_media2 = arg;
116         const char *stream_type2 = flags & OBJ_KEY ? arg : session_media2->stream_type;
117
118         return strcmp(session_media1->stream_type, stream_type2) ? 0 : CMP_MATCH | CMP_STOP;
119 }
120
121 int ast_sip_session_register_sdp_handler(struct ast_sip_session_sdp_handler *handler, const char *stream_type)
122 {
123         RAII_VAR(struct sdp_handler_list *, handler_list,
124                         ao2_find(sdp_handlers, stream_type, OBJ_KEY), ao2_cleanup);
125         SCOPED_AO2LOCK(lock, sdp_handlers);
126
127         if (handler_list) {
128                 struct ast_sip_session_sdp_handler *iter;
129                 /* Check if this handler is already registered for this stream type */
130                 AST_LIST_TRAVERSE(&handler_list->list, iter, next) {
131                         if (!strcmp(iter->id, handler->id)) {
132                                 ast_log(LOG_WARNING, "Handler '%s' already registered for stream type '%s'.\n", handler->id, stream_type);
133                                 return -1;
134                         }
135                 }
136                 AST_LIST_INSERT_TAIL(&handler_list->list, handler, next);
137                 ast_debug(1, "Registered SDP stream handler '%s' for stream type '%s'\n", handler->id, stream_type);
138                 ast_module_ref(ast_module_info->self);
139                 return 0;
140         }
141
142         /* No stream of this type has been registered yet, so we need to create a new list */
143         handler_list = ao2_alloc(sizeof(*handler_list) + strlen(stream_type), NULL);
144         if (!handler_list) {
145                 return -1;
146         }
147         /* Safe use of strcpy */
148         strcpy(handler_list->stream_type, stream_type);
149         AST_LIST_HEAD_INIT_NOLOCK(&handler_list->list);
150         AST_LIST_INSERT_TAIL(&handler_list->list, handler, next);
151         if (!ao2_link(sdp_handlers, handler_list)) {
152                 return -1;
153         }
154         ast_debug(1, "Registered SDP stream handler '%s' for stream type '%s'\n", handler->id, stream_type);
155         ast_module_ref(ast_module_info->self);
156         return 0;
157 }
158
159 static int remove_handler(void *obj, void *arg, void *data, int flags)
160 {
161         struct sdp_handler_list *handler_list = obj;
162         struct ast_sip_session_sdp_handler *handler = data;
163         struct ast_sip_session_sdp_handler *iter;
164         const char *stream_type = arg;
165
166         AST_LIST_TRAVERSE_SAFE_BEGIN(&handler_list->list, iter, next) {
167                 if (!strcmp(iter->id, handler->id)) {
168                         AST_LIST_REMOVE_CURRENT(next);
169                         ast_debug(1, "Unregistered SDP stream handler '%s' for stream type '%s'\n", handler->id, stream_type);
170                         ast_module_unref(ast_module_info->self);
171                 }
172         }
173         AST_LIST_TRAVERSE_SAFE_END;
174
175         if (AST_LIST_EMPTY(&handler_list->list)) {
176                 ast_debug(3, "No more handlers exist for stream type '%s'\n", stream_type);
177                 return CMP_MATCH;
178         } else {
179                 return CMP_STOP;
180         }
181 }
182
183 void ast_sip_session_unregister_sdp_handler(struct ast_sip_session_sdp_handler *handler, const char *stream_type)
184 {
185         ao2_callback_data(sdp_handlers, OBJ_KEY | OBJ_UNLINK | OBJ_NODATA, remove_handler, (void *)stream_type, handler);
186 }
187
188 static int validate_port_hash(const void *obj, int flags)
189 {
190         const int *port = obj;
191         return *port;
192 }
193
194 static int validate_port_cmp(void *obj, void *arg, int flags)
195 {
196         int *port1 = obj;
197         int *port2 = arg;
198
199         return *port1 == *port2 ? CMP_MATCH | CMP_STOP : 0;
200 }
201
202 struct bundle_assoc {
203         int port;
204         char tag[1];
205 };
206
207 static int bundle_assoc_hash(const void *obj, int flags)
208 {
209         const struct bundle_assoc *assoc = obj;
210         const char *tag = flags & OBJ_KEY ? obj : assoc->tag;
211
212         return ast_str_hash(tag);
213 }
214
215 static int bundle_assoc_cmp(void *obj, void *arg, int flags)
216 {
217         struct bundle_assoc *assoc1 = obj;
218         struct bundle_assoc *assoc2 = arg;
219         const char *tag2 = flags & OBJ_KEY ? arg : assoc2->tag;
220
221         return strcmp(assoc1->tag, tag2) ? 0 : CMP_MATCH | CMP_STOP;
222 }
223
224 /* return must be ast_freed */
225 static pjmedia_sdp_attr *media_get_mid(pjmedia_sdp_media *media)
226 {
227         pjmedia_sdp_attr *attr = pjmedia_sdp_media_find_attr2(media, "mid", NULL);
228         if (!attr) {
229                 return NULL;
230         }
231
232         return attr;
233 }
234
235 static int get_bundle_port(const pjmedia_sdp_session *sdp, const char *mid)
236 {
237         int i;
238         for (i = 0; i < sdp->media_count; ++i) {
239                 pjmedia_sdp_attr *mid_attr = media_get_mid(sdp->media[i]);
240                 if (mid_attr && !pj_strcmp2(&mid_attr->value, mid)) {
241                         return sdp->media[i]->desc.port;
242                 }
243         }
244
245         return -1;
246 }
247
248 static int validate_incoming_sdp(const pjmedia_sdp_session *sdp)
249 {
250         int i;
251         RAII_VAR(struct ao2_container *, portlist, ao2_container_alloc(5, validate_port_hash, validate_port_cmp), ao2_cleanup);
252         RAII_VAR(struct ao2_container *, bundle_assoc_list, ao2_container_alloc(5, bundle_assoc_hash, bundle_assoc_cmp), ao2_cleanup);
253
254         /* check for bundles (for websocket RTP multiplexing, there can be more than one) */
255         for (i = 0; i < sdp->attr_count; ++i) {
256                 char *bundle_list;
257                 int bundle_port = 0;
258                 if (pj_stricmp2(&sdp->attr[i]->name, "group")) {
259                         continue;
260                 }
261
262                 /* check to see if this group is a bundle */
263                 if (7 >= sdp->attr[i]->value.slen || pj_strnicmp2(&sdp->attr[i]->value, "bundle ", 7)) {
264                         continue;
265                 }
266
267                 bundle_list = ast_alloca(sdp->attr[i]->value.slen - 6);
268                 strncpy(bundle_list, sdp->attr[i]->value.ptr + 7, sdp->attr[i]->value.slen - 7);
269                 bundle_list[sdp->attr[i]->value.slen - 7] = '\0';
270                 while (bundle_list) {
271                         char *item;
272                         RAII_VAR(struct bundle_assoc *, assoc, NULL, ao2_cleanup);
273                         item = strsep(&bundle_list, " ,");
274                         if (!bundle_port) {
275                                 RAII_VAR(int *, port, ao2_alloc(sizeof(int), NULL), ao2_cleanup);
276                                 RAII_VAR(int *, port_match, NULL, ao2_cleanup);
277                                 bundle_port = get_bundle_port(sdp, item);
278                                 if (bundle_port < 0) {
279                                         return -1;
280                                 }
281                                 port_match = ao2_find(portlist, &bundle_port, OBJ_KEY);
282                                 if (port_match) {
283                                         /* bundle port aready consumed by a different bundle */
284                                         return -1;
285                                 }
286                                 *port = bundle_port;
287                                 ao2_link(portlist, port);
288                         }
289                         assoc = ao2_alloc(sizeof(*assoc) + strlen(item), NULL);
290                         if (!assoc) {
291                                 return -1;
292                         }
293
294                         /* safe use of strcpy */
295                         strcpy(assoc->tag, item);
296                         assoc->port = bundle_port;
297                         ao2_link(bundle_assoc_list, assoc);
298                 }
299         }
300
301         /* validate all streams */
302         for (i = 0; i < sdp->media_count; ++i) {
303                 RAII_VAR(int *, port, ao2_alloc(sizeof(int), NULL), ao2_cleanup);
304                 RAII_VAR(int *, port_match, NULL, ao2_cleanup);
305                 RAII_VAR(int *, bundle_match, NULL, ao2_cleanup);
306                 *port = sdp->media[i]->desc.port;
307                 port_match = ao2_find(portlist, port, OBJ_KEY);
308                 if (port_match) {
309                         RAII_VAR(struct bundle_assoc *, assoc, NULL, ao2_cleanup);
310                         pjmedia_sdp_attr *mid = media_get_mid(sdp->media[i]);
311                         char *mid_val;
312
313                         if (!mid) {
314                                 /* not part of a bundle */
315                                 return -1;
316                         }
317
318                         mid_val = ast_alloca(mid->value.slen + 1);
319                         strncpy(mid_val, mid->value.ptr, mid->value.slen);
320                         mid_val[mid->value.slen] = '\0';
321
322                         assoc = ao2_find(bundle_assoc_list, mid_val, OBJ_KEY);
323                         if (!assoc || assoc->port != *port) {
324                                 /* This port already exists elsewhere in the SDP
325                                  * and is not an appropriate bundle port, fail
326                                  * catastrophically */
327                                 return -1;
328                         }
329                 }
330                 ao2_link(portlist, port);
331         }
332         return 0;
333 }
334
335 static int handle_incoming_sdp(struct ast_sip_session *session, const pjmedia_sdp_session *sdp)
336 {
337         int i;
338         if (validate_incoming_sdp(sdp)) {
339                 return -1;
340         }
341
342         for (i = 0; i < sdp->media_count; ++i) {
343                 /* See if there are registered handlers for this media stream type */
344                 char media[20];
345                 struct ast_sip_session_sdp_handler *handler;
346                 RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
347                 RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
348
349                 /* We need a null-terminated version of the media string */
350                 ast_copy_pj_str(media, &sdp->media[i]->desc.media, sizeof(media));
351
352                 session_media = ao2_find(session->media, media, OBJ_KEY);
353                 if (!session_media) {
354                         /* if the session_media doesn't exist, there weren't
355                          * any handlers at the time of its creation */
356                         continue;
357                 }
358
359                 if (session_media->handler) {
360                         int res;
361                         handler = session_media->handler;
362                         res = handler->negotiate_incoming_sdp_stream(
363                                 session, session_media, sdp, sdp->media[i]);
364                         if (res <= 0) {
365                                 /* Catastrophic failure or ignored by assigned handler. Abort! */
366                                 return -1;
367                         }
368                         if (res > 0) {
369                                 /* Handled by this handler. Move to the next stream */
370                                 continue;
371                         }
372                 }
373
374                 handler_list = ao2_find(sdp_handlers, media, OBJ_KEY);
375                 if (!handler_list) {
376                         ast_debug(1, "No registered SDP handlers for media type '%s'\n", media);
377                         continue;
378                 }
379                 AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
380                         int res;
381                         if (session_media->handler) {
382                                 /* There is only one slot for this stream type and it has already been claimed
383                                  * so it will go unhandled */
384                                 break;
385                         }
386                         res = handler->negotiate_incoming_sdp_stream(session, session_media, sdp, sdp->media[i]);
387                         if (res < 0) {
388                                 /* Catastrophic failure. Abort! */
389                                 return -1;
390                         }
391                         if (res > 0) {
392                                 /* Handled by this handler. Move to the next stream */
393                                 session_media->handler = handler;
394                                 break;
395                         }
396                 }
397         }
398         return 0;
399 }
400
401 struct handle_negotiated_sdp_cb {
402         struct ast_sip_session *session;
403         const pjmedia_sdp_session *local;
404         const pjmedia_sdp_session *remote;
405 };
406
407 static int handle_negotiated_sdp_session_media(void *obj, void *arg, int flags)
408 {
409         struct ast_sip_session_media *session_media = obj;
410         struct handle_negotiated_sdp_cb *callback_data = arg;
411         struct ast_sip_session *session = callback_data->session;
412         const pjmedia_sdp_session *local = callback_data->local;
413         const pjmedia_sdp_session *remote = callback_data->remote;
414         int i;
415
416         for (i = 0; i < local->media_count; ++i) {
417                 /* See if there are registered handlers for this media stream type */
418                 char media[20];
419                 struct ast_sip_session_sdp_handler *handler;
420                 RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
421
422                 if (!remote->media[i]) {
423                         continue;
424                 }
425
426                 /* We need a null-terminated version of the media string */
427                 ast_copy_pj_str(media, &local->media[i]->desc.media, sizeof(media));
428
429                 /* stream type doesn't match the one we're looking to fill */
430                 if (strcasecmp(session_media->stream_type, media)) {
431                         continue;
432                 }
433
434                 handler = session_media->handler;
435                 if (handler) {
436                         int res = handler->apply_negotiated_sdp_stream(session, session_media, local, local->media[i], remote, remote->media[i]);
437                         if (res >= 0) {
438                                 return CMP_MATCH;
439                         }
440                         return 0;
441                 }
442
443                 handler_list = ao2_find(sdp_handlers, media, OBJ_KEY);
444                 if (!handler_list) {
445                         ast_debug(1, "No registered SDP handlers for media type '%s'\n", media);
446                         continue;
447                 }
448                 AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
449                         int res = handler->apply_negotiated_sdp_stream(session, session_media, local, local->media[i], remote, remote->media[i]);
450                         if (res < 0) {
451                                 /* Catastrophic failure. Abort! */
452                                 return 0;
453                         }
454                         if (res > 0) {
455                                 /* Handled by this handler. Move to the next stream */
456                                 session_media->handler = handler;
457                                 return CMP_MATCH;
458                         }
459                 }
460         }
461         return CMP_MATCH;
462 }
463
464 static int handle_negotiated_sdp(struct ast_sip_session *session, const pjmedia_sdp_session *local, const pjmedia_sdp_session *remote)
465 {
466         RAII_VAR(struct ao2_iterator *, successful, NULL, ao2_iterator_cleanup);
467         struct handle_negotiated_sdp_cb callback_data = {
468                 .session = session,
469                 .local = local,
470                 .remote = remote,
471         };
472
473         successful = ao2_callback(session->media, OBJ_MULTIPLE, handle_negotiated_sdp_session_media, &callback_data);
474         if (successful && ao2_iterator_count(successful) == ao2_container_count(session->media)) {
475                 /* Nothing experienced a catastrophic failure */
476                 ast_queue_frame(session->channel, &ast_null_frame);
477                 return 0;
478         }
479         return -1;
480 }
481
482 AST_RWLIST_HEAD_STATIC(session_supplements, ast_sip_session_supplement);
483
484 int ast_sip_session_register_supplement(struct ast_sip_session_supplement *supplement)
485 {
486         struct ast_sip_session_supplement *iter;
487         int inserted = 0;
488         SCOPED_LOCK(lock, &session_supplements, AST_RWLIST_WRLOCK, AST_RWLIST_UNLOCK);
489
490         AST_RWLIST_TRAVERSE_SAFE_BEGIN(&session_supplements, iter, next) {
491                 if (iter->priority > supplement->priority) {
492                         AST_RWLIST_INSERT_BEFORE_CURRENT(supplement, next);
493                         inserted = 1;
494                         break;
495                 }
496         }
497         AST_RWLIST_TRAVERSE_SAFE_END;
498
499         if (!inserted) {
500                 AST_RWLIST_INSERT_TAIL(&session_supplements, supplement, next);
501         }
502         ast_module_ref(ast_module_info->self);
503         return 0;
504 }
505
506 void ast_sip_session_unregister_supplement(struct ast_sip_session_supplement *supplement)
507 {
508         struct ast_sip_session_supplement *iter;
509         SCOPED_LOCK(lock, &session_supplements, AST_RWLIST_WRLOCK, AST_RWLIST_UNLOCK);
510         AST_RWLIST_TRAVERSE_SAFE_BEGIN(&session_supplements, iter, next) {
511                 if (supplement == iter) {
512                         AST_RWLIST_REMOVE_CURRENT(next);
513                         ast_module_unref(ast_module_info->self);
514                         break;
515                 }
516         }
517         AST_RWLIST_TRAVERSE_SAFE_END;
518 }
519
520 static struct ast_sip_session_supplement *supplement_dup(const struct ast_sip_session_supplement *src)
521 {
522         struct ast_sip_session_supplement *dst = ast_calloc(1, sizeof(*dst));
523         if (!dst) {
524                 return NULL;
525         }
526         /* Will need to revisit if shallow copy becomes an issue */
527         *dst = *src;
528         return dst;
529 }
530
531 #define DATASTORE_BUCKETS 53
532 #define MEDIA_BUCKETS 7
533
534 static void session_datastore_destroy(void *obj)
535 {
536         struct ast_datastore *datastore = obj;
537
538         /* Using the destroy function (if present) destroy the data */
539         if (datastore->info->destroy != NULL && datastore->data != NULL) {
540                 datastore->info->destroy(datastore->data);
541                 datastore->data = NULL;
542         }
543
544         ast_free((void *) datastore->uid);
545         datastore->uid = NULL;
546 }
547
548 struct ast_datastore *ast_sip_session_alloc_datastore(const struct ast_datastore_info *info, const char *uid)
549 {
550         RAII_VAR(struct ast_datastore *, datastore, NULL, ao2_cleanup);
551         const char *uid_ptr = uid;
552
553         if (!info) {
554                 return NULL;
555         }
556
557         datastore = ao2_alloc(sizeof(*datastore), session_datastore_destroy);
558         if (!datastore) {
559                 return NULL;
560         }
561
562         datastore->info = info;
563         if (ast_strlen_zero(uid)) {
564                 /* They didn't provide an ID so we'll provide one ourself */
565                 struct ast_uuid *uuid = ast_uuid_generate();
566                 char uuid_buf[AST_UUID_STR_LEN];
567                 if (!uuid) {
568                         return NULL;
569                 }
570                 uid_ptr = ast_uuid_to_str(uuid, uuid_buf, sizeof(uuid_buf));
571                 ast_free(uuid);
572         }
573
574         datastore->uid = ast_strdup(uid_ptr);
575         if (!datastore->uid) {
576                 return NULL;
577         }
578
579         ao2_ref(datastore, +1);
580         return datastore;
581 }
582
583 int ast_sip_session_add_datastore(struct ast_sip_session *session, struct ast_datastore *datastore)
584 {
585         ast_assert(datastore != NULL);
586         ast_assert(datastore->info != NULL);
587         ast_assert(ast_strlen_zero(datastore->uid) == 0);
588
589         if (!ao2_link(session->datastores, datastore)) {
590                 return -1;
591         }
592         return 0;
593 }
594
595 struct ast_datastore *ast_sip_session_get_datastore(struct ast_sip_session *session, const char *name)
596 {
597         return ao2_find(session->datastores, name, OBJ_KEY);
598 }
599
600 void ast_sip_session_remove_datastore(struct ast_sip_session *session, const char *name)
601 {
602         ao2_callback(session->datastores, OBJ_KEY | OBJ_UNLINK | OBJ_NODATA, NULL, (void *) name);
603 }
604
605 /*!
606  * \brief Structure used for sending delayed requests
607  *
608  * Requests are typically delayed because the current transaction
609  * state of an INVITE. Once the pending INVITE transaction terminates,
610  * the delayed request will be sent
611  */
612 struct ast_sip_session_delayed_request {
613         /*! Method of the request */
614         char method[15];
615         /*! Callback to call when the delayed request is created. */
616         ast_sip_session_request_creation_cb on_request_creation;
617         /*! Callback to call when the delayed request SDP is created */
618         ast_sip_session_sdp_creation_cb on_sdp_creation;
619         /*! Callback to call when the delayed request receives a response */
620         ast_sip_session_response_cb on_response;
621         /*! Request to send */
622         pjsip_tx_data *tdata;
623         AST_LIST_ENTRY(ast_sip_session_delayed_request) next;
624 };
625
626 static struct ast_sip_session_delayed_request *delayed_request_alloc(const char *method,
627                 ast_sip_session_request_creation_cb on_request_creation,
628                 ast_sip_session_sdp_creation_cb on_sdp_creation,
629                 ast_sip_session_response_cb on_response,
630                 pjsip_tx_data *tdata)
631 {
632         struct ast_sip_session_delayed_request *delay = ast_calloc(1, sizeof(*delay));
633         if (!delay) {
634                 return NULL;
635         }
636         ast_copy_string(delay->method, method, sizeof(delay->method));
637         delay->on_request_creation = on_request_creation;
638         delay->on_sdp_creation = on_sdp_creation;
639         delay->on_response = on_response;
640         delay->tdata = tdata;
641         return delay;
642 }
643
644 static int send_delayed_request(struct ast_sip_session *session, struct ast_sip_session_delayed_request *delay)
645 {
646         ast_debug(3, "Sending delayed %s request to %s\n", delay->method, ast_sorcery_object_get_id(session->endpoint));
647
648         if (delay->tdata) {
649                 ast_sip_session_send_request_with_cb(session, delay->tdata, delay->on_response);
650                 return 0;
651         }
652
653         if (!strcmp(delay->method, "INVITE")) {
654                 ast_sip_session_refresh(session, delay->on_request_creation,
655                                 delay->on_sdp_creation, delay->on_response, AST_SIP_SESSION_REFRESH_METHOD_INVITE, 1);
656         } else if (!strcmp(delay->method, "UPDATE")) {
657                 ast_sip_session_refresh(session, delay->on_request_creation,
658                                 delay->on_sdp_creation, delay->on_response, AST_SIP_SESSION_REFRESH_METHOD_UPDATE, 1);
659         } else {
660                 ast_log(LOG_WARNING, "Unexpected delayed %s request with no existing request structure\n", delay->method);
661                 return -1;
662         }
663         return 0;
664 }
665
666 static int queued_delayed_request_send(void *data)
667 {
668         RAII_VAR(struct ast_sip_session *, session, data, ao2_cleanup);
669         RAII_VAR(struct ast_sip_session_delayed_request *, delay, NULL, ast_free_ptr);
670
671         delay = AST_LIST_REMOVE_HEAD(&session->delayed_requests, next);
672         if (!delay) {
673                 return 0;
674         }
675
676         return send_delayed_request(session, delay);
677 }
678
679 static void queue_delayed_request(struct ast_sip_session *session)
680 {
681         if (AST_LIST_EMPTY(&session->delayed_requests)) {
682                 /* No delayed request to send, so just return */
683                 return;
684         }
685
686         ast_debug(3, "Queuing delayed request to run for %s\n",
687                         ast_sorcery_object_get_id(session->endpoint));
688
689         ao2_ref(session, +1);
690         ast_sip_push_task(session->serializer, queued_delayed_request_send, session);
691 }
692
693 static int delay_request(struct ast_sip_session *session, ast_sip_session_request_creation_cb on_request,
694                 ast_sip_session_sdp_creation_cb on_sdp_creation, ast_sip_session_response_cb on_response,
695                 const char *method, pjsip_tx_data *tdata)
696 {
697         struct ast_sip_session_delayed_request *delay = delayed_request_alloc(method,
698                         on_request, on_sdp_creation, on_response, tdata);
699
700         if (!delay) {
701                 return -1;
702         }
703
704         AST_LIST_INSERT_TAIL(&session->delayed_requests, delay, next);
705         return 0;
706 }
707
708 static pjmedia_sdp_session *generate_session_refresh_sdp(struct ast_sip_session *session)
709 {
710         pjsip_inv_session *inv_session = session->inv_session;
711         const pjmedia_sdp_session *previous_sdp;
712
713         if (pjmedia_sdp_neg_was_answer_remote(inv_session->neg)) {
714                 pjmedia_sdp_neg_get_active_remote(inv_session->neg, &previous_sdp);
715         } else {
716                 pjmedia_sdp_neg_get_active_local(inv_session->neg, &previous_sdp);
717         }
718         return create_local_sdp(inv_session, session, previous_sdp);
719 }
720
721 int ast_sip_session_refresh(struct ast_sip_session *session,
722                 ast_sip_session_request_creation_cb on_request_creation,
723                 ast_sip_session_sdp_creation_cb on_sdp_creation,
724                 ast_sip_session_response_cb on_response,
725                 enum ast_sip_session_refresh_method method, int generate_new_sdp)
726 {
727         pjsip_inv_session *inv_session = session->inv_session;
728         pjmedia_sdp_session *new_sdp = NULL;
729         pjsip_tx_data *tdata;
730
731         if (inv_session->state == PJSIP_INV_STATE_DISCONNECTED) {
732                 /* Don't try to do anything with a hung-up call */
733                 ast_debug(3, "Not sending reinvite to %s because of disconnected state...\n",
734                                 ast_sorcery_object_get_id(session->endpoint));
735                 return 0;
736         }
737
738         if (method == AST_SIP_SESSION_REFRESH_METHOD_INVITE) {
739                 if (inv_session->invite_tsx) {
740                         /* We can't send a reinvite yet, so delay it */
741                         ast_debug(3, "Delaying sending reinvite to %s because of outstanding transaction...\n",
742                                         ast_sorcery_object_get_id(session->endpoint));
743                         return delay_request(session, on_request_creation, on_sdp_creation, on_response, "INVITE", NULL);
744                 } else if (inv_session->state != PJSIP_INV_STATE_CONFIRMED) {
745                         /* Initial INVITE transaction failed to progress us to a confirmed state
746                          * which means re-invites are not possible
747                          */
748                         ast_debug(3, "Not sending reinvite to %s because not in confirmed state...\n",
749                                         ast_sorcery_object_get_id(session->endpoint));
750                         return 0;
751                 }
752         }
753
754         if (generate_new_sdp) {
755                 new_sdp = generate_session_refresh_sdp(session);
756                 if (!new_sdp) {
757                         ast_log(LOG_ERROR, "Failed to generate session refresh SDP. Not sending session refresh\n");
758                         return -1;
759                 }
760                 if (on_sdp_creation) {
761                         if (on_sdp_creation(session, new_sdp)) {
762                                 return -1;
763                         }
764                 }
765         }
766
767         if (method == AST_SIP_SESSION_REFRESH_METHOD_INVITE) {
768                 if (pjsip_inv_reinvite(inv_session, NULL, new_sdp, &tdata)) {
769                         ast_log(LOG_WARNING, "Failed to create reinvite properly.\n");
770                         return -1;
771                 }
772         } else if (pjsip_inv_update(inv_session, NULL, new_sdp, &tdata)) {
773                 ast_log(LOG_WARNING, "Failed to create UPDATE properly.\n");
774                 return -1;
775         }
776         if (on_request_creation) {
777                 if (on_request_creation(session, tdata)) {
778                         return -1;
779                 }
780         }
781         ast_sip_session_send_request_with_cb(session, tdata, on_response);
782         return 0;
783 }
784
785 void ast_sip_session_send_response(struct ast_sip_session *session, pjsip_tx_data *tdata)
786 {
787         handle_outgoing_response(session, tdata);
788         pjsip_inv_send_msg(session->inv_session, tdata);
789         return;
790 }
791
792 static pj_bool_t session_on_rx_request(pjsip_rx_data *rdata);
793
794 static pjsip_module session_module = {
795         .name = {"Session Module", 14},
796         .priority = PJSIP_MOD_PRIORITY_APPLICATION,
797         .on_rx_request = session_on_rx_request,
798 };
799
800 /*! \brief Determine whether the SDP provided requires deferral of negotiating or not
801  *
802  * \retval 1 re-invite should be deferred and resumed later
803  * \retval 0 re-invite should not be deferred
804  */
805 static int sdp_requires_deferral(struct ast_sip_session *session, const pjmedia_sdp_session *sdp)
806 {
807         int i;
808         if (validate_incoming_sdp(sdp)) {
809                 return 0;
810         }
811
812         for (i = 0; i < sdp->media_count; ++i) {
813                 /* See if there are registered handlers for this media stream type */
814                 char media[20];
815                 struct ast_sip_session_sdp_handler *handler;
816                 RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
817                 RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
818
819                 /* We need a null-terminated version of the media string */
820                 ast_copy_pj_str(media, &sdp->media[i]->desc.media, sizeof(media));
821
822                 session_media = ao2_find(session->media, media, OBJ_KEY);
823                 if (!session_media) {
824                         /* if the session_media doesn't exist, there weren't
825                          * any handlers at the time of its creation */
826                         continue;
827                 }
828
829                 if (session_media->handler && session_media->handler->defer_incoming_sdp_stream) {
830                         int res;
831                         handler = session_media->handler;
832                         res = handler->defer_incoming_sdp_stream(
833                                 session, session_media, sdp, sdp->media[i]);
834                         if (res) {
835                                 return 1;
836                         }
837                 }
838
839                 handler_list = ao2_find(sdp_handlers, media, OBJ_KEY);
840                 if (!handler_list) {
841                         ast_debug(1, "No registered SDP handlers for media type '%s'\n", media);
842                         continue;
843                 }
844                 AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
845                         int res;
846                         if (session_media->handler) {
847                                 /* There is only one slot for this stream type and it has already been claimed
848                                  * so it will go unhandled */
849                                 break;
850                         }
851                         if (!handler->defer_incoming_sdp_stream) {
852                                 continue;
853                         }
854                         res = handler->defer_incoming_sdp_stream(session, session_media, sdp, sdp->media[i]);
855                         if (res) {
856                                 return 1;
857                         }
858                 }
859         }
860         return 0;
861 }
862
863 static pj_bool_t session_reinvite_on_rx_request(pjsip_rx_data *rdata)
864 {
865         pjsip_dialog *dlg;
866         RAII_VAR(struct ast_sip_session *, session, NULL, ao2_cleanup);
867         pjsip_rdata_sdp_info *sdp_info;
868
869         if (rdata->msg_info.msg->line.req.method.id != PJSIP_INVITE_METHOD ||
870                 !(dlg = pjsip_ua_find_dialog(&rdata->msg_info.cid->id, &rdata->msg_info.to->tag, &rdata->msg_info.from->tag, PJ_FALSE)) ||
871                 !(session = ast_sip_dialog_get_session(dlg))) {
872                 return PJ_FALSE;
873         }
874
875         if (session->deferred_reinvite) {
876                 pj_str_t key, deferred_key;
877                 pjsip_tx_data *tdata;
878
879                 /* We use memory from the new request on purpose so the deferred reinvite pool does not grow uncontrollably */
880                 pjsip_tsx_create_key(rdata->tp_info.pool, &key, PJSIP_ROLE_UAS, &rdata->msg_info.cseq->method, rdata);
881                 pjsip_tsx_create_key(rdata->tp_info.pool, &deferred_key, PJSIP_ROLE_UAS, &session->deferred_reinvite->msg_info.cseq->method,
882                         session->deferred_reinvite);
883
884                 /* If this is a retransmission ignore it */
885                 if (!pj_strcmp(&key, &deferred_key)) {
886                         return PJ_TRUE;
887                 }
888
889                 /* Otherwise this is a new re-invite, so reject it */
890                 if (pjsip_dlg_create_response(dlg, rdata, 491, NULL, &tdata) == PJ_SUCCESS) {
891                         pjsip_endpt_send_response2(ast_sip_get_pjsip_endpoint(), rdata, tdata, NULL, NULL);
892                 }
893
894                 return PJ_TRUE;
895         }
896
897         if (!(sdp_info = pjsip_rdata_get_sdp_info(rdata)) ||
898                 (sdp_info->sdp_err != PJ_SUCCESS)) {
899                 return PJ_FALSE;
900         }
901
902         if (!sdp_info->sdp) {
903                 ast_queue_unhold(session->channel);
904                 return PJ_FALSE;
905         }
906
907         if (!sdp_requires_deferral(session, sdp_info->sdp)) {
908                 return PJ_FALSE;
909         }
910
911         pjsip_rx_data_clone(rdata, 0, &session->deferred_reinvite);
912
913         return PJ_TRUE;
914 }
915
916 void ast_sip_session_resume_reinvite(struct ast_sip_session *session)
917 {
918         if (!session->deferred_reinvite) {
919                 return;
920         }
921
922         pjsip_endpt_process_rx_data(ast_sip_get_pjsip_endpoint(), session->deferred_reinvite, NULL, NULL);
923         pjsip_rx_data_free_cloned(session->deferred_reinvite);
924         session->deferred_reinvite = NULL;
925 }
926
927 static pjsip_module session_reinvite_module = {
928         .name = { "Session Re-Invite Module", 24 },
929         .priority = PJSIP_MOD_PRIORITY_UA_PROXY_LAYER - 1,
930         .on_rx_request = session_reinvite_on_rx_request,
931 };
932
933 void ast_sip_session_send_request_with_cb(struct ast_sip_session *session, pjsip_tx_data *tdata,
934                 ast_sip_session_response_cb on_response)
935 {
936         pjsip_inv_session *inv_session = session->inv_session;
937
938         if (inv_session->state == PJSIP_INV_STATE_DISCONNECTED) {
939                 /* Don't try to do anything with a hung-up call */
940                 return;
941         }
942
943         ast_sip_mod_data_set(tdata->pool, tdata->mod_data, session_module.id,
944                              MOD_DATA_ON_RESPONSE, on_response);
945
946         if (!ast_strlen_zero(session->endpoint->fromuser) ||
947                 !ast_strlen_zero(session->endpoint->fromdomain)) {
948                 pjsip_fromto_hdr *from = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_FROM, tdata->msg->hdr.next);
949                 pjsip_sip_uri *uri = pjsip_uri_get_uri(from->uri);
950
951                 if (!ast_strlen_zero(session->endpoint->fromuser)) {
952                         pj_strdup2(tdata->pool, &uri->user, session->endpoint->fromuser);
953                 }
954                 if (!ast_strlen_zero(session->endpoint->fromdomain)) {
955                         pj_strdup2(tdata->pool, &uri->host, session->endpoint->fromdomain);
956                 }
957         }
958
959         handle_outgoing_request(session, tdata);
960         pjsip_inv_send_msg(session->inv_session, tdata);
961         return;
962 }
963
964 void ast_sip_session_send_request(struct ast_sip_session *session, pjsip_tx_data *tdata)
965 {
966         ast_sip_session_send_request_with_cb(session, tdata, NULL);
967 }
968
969 int ast_sip_session_create_invite(struct ast_sip_session *session, pjsip_tx_data **tdata)
970 {
971         pjmedia_sdp_session *offer;
972
973         if (!(offer = create_local_sdp(session->inv_session, session, NULL))) {
974                 pjsip_inv_terminate(session->inv_session, 500, PJ_FALSE);
975                 return -1;
976         }
977
978         pjsip_inv_set_local_sdp(session->inv_session, offer);
979         pjmedia_sdp_neg_set_prefer_remote_codec_order(session->inv_session->neg, PJ_FALSE);
980 #ifdef PJMEDIA_SDP_NEG_ANSWER_MULTIPLE_CODECS
981         pjmedia_sdp_neg_set_answer_multiple_codecs(session->inv_session->neg, PJ_TRUE);
982 #endif
983         if (pjsip_inv_invite(session->inv_session, tdata) != PJ_SUCCESS) {
984                 return -1;
985         }
986         return 0;
987 }
988
989 static int datastore_hash(const void *obj, int flags)
990 {
991         const struct ast_datastore *datastore = obj;
992         const char *uid = flags & OBJ_KEY ? obj : datastore->uid;
993
994         ast_assert(uid != NULL);
995
996         return ast_str_hash(uid);
997 }
998
999 static int datastore_cmp(void *obj, void *arg, int flags)
1000 {
1001         const struct ast_datastore *datastore1 = obj;
1002         const struct ast_datastore *datastore2 = arg;
1003         const char *uid2 = flags & OBJ_KEY ? arg : datastore2->uid;
1004
1005         ast_assert(datastore1->uid != NULL);
1006         ast_assert(uid2 != NULL);
1007
1008         return strcmp(datastore1->uid, uid2) ? 0 : CMP_MATCH | CMP_STOP;
1009 }
1010
1011 static void session_media_dtor(void *obj)
1012 {
1013         struct ast_sip_session_media *session_media = obj;
1014         if (session_media->handler) {
1015                 session_media->handler->stream_destroy(session_media);
1016         }
1017         if (session_media->srtp) {
1018                 ast_sdp_srtp_destroy(session_media->srtp);
1019         }
1020 }
1021
1022 static void session_destructor(void *obj)
1023 {
1024         struct ast_sip_session *session = obj;
1025         struct ast_sip_session_supplement *supplement;
1026         struct ast_sip_session_delayed_request *delay;
1027
1028         ast_debug(3, "Destroying SIP session with endpoint %s\n",
1029                         ast_sorcery_object_get_id(session->endpoint));
1030
1031         while ((supplement = AST_LIST_REMOVE_HEAD(&session->supplements, next))) {
1032                 if (supplement->session_destroy) {
1033                         supplement->session_destroy(session);
1034                 }
1035                 ast_free(supplement);
1036         }
1037
1038         ast_taskprocessor_unreference(session->serializer);
1039         ao2_cleanup(session->datastores);
1040         ao2_cleanup(session->media);
1041
1042         AST_LIST_HEAD_DESTROY(&session->supplements);
1043         while ((delay = AST_LIST_REMOVE_HEAD(&session->delayed_requests, next))) {
1044                 ast_free(delay);
1045         }
1046         ast_party_id_free(&session->id);
1047         ao2_cleanup(session->endpoint);
1048         ast_format_cap_destroy(session->req_caps);
1049         ast_format_cap_destroy(session->direct_media_cap);
1050
1051         if (session->dsp) {
1052                 ast_dsp_free(session->dsp);
1053         }
1054
1055         if (session->inv_session) {
1056                 pjsip_dlg_dec_session(session->inv_session->dlg, &session_module);
1057         }
1058 }
1059
1060 static int add_supplements(struct ast_sip_session *session)
1061 {
1062         struct ast_sip_session_supplement *iter;
1063         SCOPED_LOCK(lock, &session_supplements, AST_RWLIST_RDLOCK, AST_RWLIST_UNLOCK);
1064
1065         AST_RWLIST_TRAVERSE(&session_supplements, iter, next) {
1066                 struct ast_sip_session_supplement *copy = supplement_dup(iter);
1067                 if (!copy) {
1068                         return -1;
1069                 }
1070                 AST_LIST_INSERT_TAIL(&session->supplements, copy, next);
1071         }
1072         return 0;
1073 }
1074
1075 static int add_session_media(void *obj, void *arg, int flags)
1076 {
1077         struct sdp_handler_list *handler_list = obj;
1078         struct ast_sip_session * session = arg;
1079         RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
1080         session_media = ao2_alloc(sizeof(*session_media) + strlen(handler_list->stream_type), session_media_dtor);
1081         if (!session_media) {
1082                 return CMP_STOP;
1083         }
1084         /* Safe use of strcpy */
1085         strcpy(session_media->stream_type, handler_list->stream_type);
1086         ao2_link(session->media, session_media);
1087         return 0;
1088 }
1089
1090 /*! \brief Destructor for SIP channel */
1091 static void sip_channel_destroy(void *obj)
1092 {
1093         struct ast_sip_channel_pvt *channel = obj;
1094
1095         ao2_cleanup(channel->pvt);
1096         ao2_cleanup(channel->session);
1097 }
1098
1099 struct ast_sip_channel_pvt *ast_sip_channel_pvt_alloc(void *pvt, struct ast_sip_session *session)
1100 {
1101         struct ast_sip_channel_pvt *channel = ao2_alloc(sizeof(*channel), sip_channel_destroy);
1102
1103         if (!channel) {
1104                 return NULL;
1105         }
1106
1107         ao2_ref(pvt, +1);
1108         channel->pvt = pvt;
1109         ao2_ref(session, +1);
1110         channel->session = session;
1111
1112         return channel;
1113 }
1114
1115 struct ast_sip_session *ast_sip_session_alloc(struct ast_sip_endpoint *endpoint, pjsip_inv_session *inv_session)
1116 {
1117         RAII_VAR(struct ast_sip_session *, session, ao2_alloc(sizeof(*session), session_destructor), ao2_cleanup);
1118         struct ast_sip_session_supplement *iter;
1119         int dsp_features = 0;
1120         if (!session) {
1121                 return NULL;
1122         }
1123         AST_LIST_HEAD_INIT(&session->supplements);
1124         session->datastores = ao2_container_alloc(DATASTORE_BUCKETS, datastore_hash, datastore_cmp);
1125         if (!session->datastores) {
1126                 return NULL;
1127         }
1128
1129         session->media = ao2_container_alloc(MEDIA_BUCKETS, session_media_hash, session_media_cmp);
1130         if (!session->media) {
1131                 return NULL;
1132         }
1133         /* fill session->media with available types */
1134         ao2_callback(sdp_handlers, OBJ_NODATA, add_session_media, session);
1135
1136         session->serializer = ast_sip_create_serializer();
1137         if (!session->serializer) {
1138                 return NULL;
1139         }
1140         ast_sip_dialog_set_serializer(inv_session->dlg, session->serializer);
1141         ast_sip_dialog_set_endpoint(inv_session->dlg, endpoint);
1142         pjsip_dlg_inc_session(inv_session->dlg, &session_module);
1143         ao2_ref(session, +1);
1144         inv_session->mod_data[session_module.id] = session;
1145         ao2_ref(endpoint, +1);
1146         session->endpoint = endpoint;
1147         session->inv_session = inv_session;
1148         session->req_caps = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_NOLOCK);
1149
1150         if (endpoint->dtmf == AST_SIP_DTMF_INBAND) {
1151                 dsp_features |= DSP_FEATURE_DIGIT_DETECT;
1152         }
1153
1154         if (endpoint->faxdetect) {
1155                 dsp_features |= DSP_FEATURE_FAX_DETECT;
1156         }
1157
1158         if (dsp_features) {
1159                 if (!(session->dsp = ast_dsp_new())) {
1160                         ao2_ref(session, -1);
1161                         return NULL;
1162                 }
1163
1164                 ast_dsp_set_features(session->dsp, dsp_features);
1165         }
1166
1167         if (add_supplements(session)) {
1168                 ao2_ref(session, -1);
1169                 return NULL;
1170         }
1171         AST_LIST_TRAVERSE(&session->supplements, iter, next) {
1172                 if (iter->session_begin) {
1173                         iter->session_begin(session);
1174                 }
1175         }
1176         session->direct_media_cap = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_NOLOCK);
1177         AST_LIST_HEAD_INIT_NOLOCK(&session->delayed_requests);
1178         ast_party_id_init(&session->id);
1179         ao2_ref(session, +1);
1180         return session;
1181 }
1182
1183 static int session_outbound_auth(pjsip_dialog *dlg, pjsip_tx_data *tdata, void *user_data)
1184 {
1185         pjsip_inv_session *inv = pjsip_dlg_get_inv_session(dlg);
1186         struct ast_sip_session *session = inv->mod_data[session_module.id];
1187
1188         if (inv->state < PJSIP_INV_STATE_CONFIRMED && tdata->msg->line.req.method.id == PJSIP_INVITE_METHOD) {
1189                 pjsip_inv_uac_restart(inv, PJ_FALSE);
1190         }
1191         ast_sip_session_send_request(session, tdata);
1192         return 0;
1193 }
1194
1195 struct ast_sip_session *ast_sip_session_create_outgoing(struct ast_sip_endpoint *endpoint, const char *location, const char *request_user, struct ast_format_cap *req_caps)
1196 {
1197         const char *uri = NULL;
1198         RAII_VAR(struct ast_sip_contact *, contact, NULL, ao2_cleanup);
1199         pjsip_timer_setting timer;
1200         pjsip_dialog *dlg;
1201         struct pjsip_inv_session *inv_session;
1202         RAII_VAR(struct ast_sip_session *, session, NULL, ao2_cleanup);
1203
1204         /* If no location has been provided use the AOR list from the endpoint itself */
1205         location = S_OR(location, endpoint->aors);
1206
1207         contact = ast_sip_location_retrieve_contact_from_aor_list(location);
1208         if (!contact || ast_strlen_zero(contact->uri)) {
1209                 uri = location;
1210         } else {
1211                 uri = contact->uri;
1212         }
1213
1214         /* If we still have no URI to dial fail to create the session */
1215         if (ast_strlen_zero(uri)) {
1216                 return NULL;
1217         }
1218
1219         if (!(dlg = ast_sip_create_dialog_uac(endpoint, uri, request_user))) {
1220                 return NULL;
1221         }
1222
1223         if (ast_sip_dialog_setup_outbound_authentication(dlg, endpoint, session_outbound_auth, NULL)) {
1224                 pjsip_dlg_terminate(dlg);
1225                 return NULL;
1226         }
1227
1228         if (pjsip_inv_create_uac(dlg, NULL, endpoint->extensions.flags, &inv_session) != PJ_SUCCESS) {
1229                 pjsip_dlg_terminate(dlg);
1230                 return NULL;
1231         }
1232 #if defined(HAVE_PJSIP_REPLACE_MEDIA_STREAM) || defined(PJMEDIA_SDP_NEG_ALLOW_MEDIA_CHANGE)
1233         inv_session->sdp_neg_flags = PJMEDIA_SDP_NEG_ALLOW_MEDIA_CHANGE;
1234 #endif
1235
1236         pjsip_timer_setting_default(&timer);
1237         timer.min_se = endpoint->extensions.timer.min_se;
1238         timer.sess_expires = endpoint->extensions.timer.sess_expires;
1239         pjsip_timer_init_session(inv_session, &timer);
1240
1241         if (!(session = ast_sip_session_alloc(endpoint, inv_session))) {
1242                 pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1243                 return NULL;
1244         }
1245
1246         ast_format_cap_copy(session->req_caps, req_caps);
1247         if ((pjsip_dlg_add_usage(dlg, &session_module, NULL) != PJ_SUCCESS)) {
1248                 pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1249                 /* Since we are not notifying ourselves that the INVITE session is being terminated
1250                  * we need to manually drop its reference to session
1251                  */
1252                 ao2_ref(session, -1);
1253                 return NULL;
1254         }
1255
1256         ao2_ref(session, +1);
1257         return session;
1258 }
1259
1260 static int session_termination_task(void *data)
1261 {
1262         RAII_VAR(struct ast_sip_session *, session, data, ao2_cleanup);
1263         pjsip_tx_data *packet = NULL;
1264
1265         if (!session->inv_session) {
1266                 return 0;
1267         }
1268
1269         if (pjsip_inv_end_session(session->inv_session, 603, NULL, &packet) == PJ_SUCCESS) {
1270                 ast_sip_session_send_request(session, packet);
1271         }
1272
1273         return 0;
1274 }
1275
1276 static void session_termination_cb(pj_timer_heap_t *timer_heap, struct pj_timer_entry *entry)
1277 {
1278         struct ast_sip_session *session = entry->user_data;
1279
1280         if (ast_sip_push_task(session->serializer, session_termination_task, session)) {
1281                 ao2_cleanup(session);
1282         }
1283 }
1284
1285 void ast_sip_session_defer_termination(struct ast_sip_session *session)
1286 {
1287         pj_time_val delay = { .sec = 60, };
1288
1289         session->defer_terminate = 1;
1290
1291         session->scheduled_termination.id = 0;
1292         ao2_ref(session, +1);
1293         session->scheduled_termination.user_data = session;
1294         session->scheduled_termination.cb = session_termination_cb;
1295
1296         if (pjsip_endpt_schedule_timer(ast_sip_get_pjsip_endpoint(), &session->scheduled_termination, &delay) != PJ_SUCCESS) {
1297                 ao2_ref(session, -1);
1298         }
1299 }
1300
1301 struct ast_sip_session *ast_sip_dialog_get_session(pjsip_dialog *dlg)
1302 {
1303         pjsip_inv_session *inv_session = pjsip_dlg_get_inv_session(dlg);
1304         struct ast_sip_session *session;
1305
1306         if (!inv_session ||
1307                 !(session = inv_session->mod_data[session_module.id])) {
1308                 return NULL;
1309         }
1310
1311         ao2_ref(session, +1);
1312
1313         return session;
1314 }
1315
1316 enum sip_get_destination_result {
1317         /*! The extension was successfully found */
1318         SIP_GET_DEST_EXTEN_FOUND,
1319         /*! The extension specified in the RURI was not found */
1320         SIP_GET_DEST_EXTEN_NOT_FOUND,
1321         /*! The extension specified in the RURI was a partial match */
1322         SIP_GET_DEST_EXTEN_PARTIAL,
1323         /*! The RURI is of an unsupported scheme */
1324         SIP_GET_DEST_UNSUPPORTED_URI,
1325 };
1326
1327 /*!
1328  * \brief Determine where in the dialplan a call should go
1329  *
1330  * This uses the username in the request URI to try to match
1331  * an extension in the endpoint's configured context in order
1332  * to route the call.
1333  *
1334  * \param session The inbound SIP session
1335  * \param rdata The SIP INVITE
1336  */
1337 static enum sip_get_destination_result get_destination(struct ast_sip_session *session, pjsip_rx_data *rdata)
1338 {
1339         pjsip_uri *ruri = rdata->msg_info.msg->line.req.uri;
1340         pjsip_sip_uri *sip_ruri;
1341         if (!PJSIP_URI_SCHEME_IS_SIP(ruri) && !PJSIP_URI_SCHEME_IS_SIPS(ruri)) {
1342                 return SIP_GET_DEST_UNSUPPORTED_URI;
1343         }
1344         sip_ruri = pjsip_uri_get_uri(ruri);
1345         ast_copy_pj_str(session->exten, &sip_ruri->user, sizeof(session->exten));
1346         if (ast_exists_extension(NULL, session->endpoint->context, session->exten, 1, NULL)) {
1347                 return SIP_GET_DEST_EXTEN_FOUND;
1348         }
1349         /* XXX In reality, we'll likely have further options so that partial matches
1350          * can be indicated here, but for getting something up and running, we're going
1351          * to return a "not exists" error here.
1352          */
1353         return SIP_GET_DEST_EXTEN_NOT_FOUND;
1354 }
1355
1356 static pjsip_inv_session *pre_session_setup(pjsip_rx_data *rdata, const struct ast_sip_endpoint *endpoint)
1357 {
1358         pjsip_tx_data *tdata;
1359         pjsip_dialog *dlg;
1360         pjsip_inv_session *inv_session;
1361         unsigned int options = endpoint->extensions.flags;
1362
1363         if (pjsip_inv_verify_request(rdata, &options, NULL, NULL, ast_sip_get_pjsip_endpoint(), &tdata) != PJ_SUCCESS) {
1364                 if (tdata) {
1365                         pjsip_endpt_send_response2(ast_sip_get_pjsip_endpoint(), rdata, tdata, NULL, NULL);
1366                 } else {
1367                         pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 500, NULL, NULL, NULL);
1368                 }
1369                 return NULL;
1370         }
1371         dlg = ast_sip_create_dialog_uas(endpoint, rdata);
1372         if (!dlg) {
1373                 pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 500, NULL, NULL, NULL);
1374                 return NULL;
1375         }
1376         if (pjsip_inv_create_uas(dlg, rdata, NULL, 0, &inv_session) != PJ_SUCCESS) {
1377                 pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 500, NULL, NULL, NULL);
1378                 pjsip_dlg_terminate(dlg);
1379                 return NULL;
1380         }
1381
1382 #if defined(HAVE_PJSIP_REPLACE_MEDIA_STREAM) || defined(PJMEDIA_SDP_NEG_ALLOW_MEDIA_CHANGE)
1383         inv_session->sdp_neg_flags = PJMEDIA_SDP_NEG_ALLOW_MEDIA_CHANGE;
1384 #endif
1385         if (pjsip_dlg_add_usage(dlg, &session_module, NULL) != PJ_SUCCESS) {
1386                 if (pjsip_inv_initial_answer(inv_session, rdata, 500, NULL, NULL, &tdata) != PJ_SUCCESS) {
1387                         pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1388                 }
1389                 pjsip_inv_send_msg(inv_session, tdata);
1390                 return NULL;
1391         }
1392         return inv_session;
1393 }
1394
1395 struct new_invite {
1396         /*! \brief Session created for the new INVITE */
1397         struct ast_sip_session *session;
1398
1399         /*! \brief INVITE request itself */
1400         pjsip_rx_data *rdata;
1401 };
1402
1403 static void new_invite_destroy(void *obj)
1404 {
1405         struct new_invite *invite = obj;
1406
1407         ao2_cleanup(invite->session);
1408
1409         if (invite->rdata) {
1410                 pjsip_rx_data_free_cloned(invite->rdata);
1411         }
1412 }
1413
1414 static struct new_invite *new_invite_alloc(struct ast_sip_session *session, pjsip_rx_data *rdata)
1415 {
1416         struct new_invite *invite = ao2_alloc(sizeof(*invite), new_invite_destroy);
1417
1418         if (!invite) {
1419                 return NULL;
1420         }
1421
1422         ao2_ref(session, +1);
1423         invite->session = session;
1424
1425         if (pjsip_rx_data_clone(rdata, 0, &invite->rdata) != PJ_SUCCESS) {
1426                 ao2_ref(invite, -1);
1427                 return NULL;
1428         }
1429
1430         return invite;
1431 }
1432
1433 static int new_invite(void *data)
1434 {
1435         RAII_VAR(struct new_invite *, invite, data, ao2_cleanup);
1436         pjsip_tx_data *tdata = NULL;
1437         pjsip_timer_setting timer;
1438         pjsip_rdata_sdp_info *sdp_info;
1439         pjmedia_sdp_session *local = NULL;
1440
1441         /* From this point on, any calls to pjsip_inv_terminate have the last argument as PJ_TRUE
1442          * so that we will be notified so we can destroy the session properly
1443          */
1444
1445         switch (get_destination(invite->session, invite->rdata)) {
1446         case SIP_GET_DEST_EXTEN_FOUND:
1447                 /* Things worked. Keep going */
1448                 break;
1449         case SIP_GET_DEST_UNSUPPORTED_URI:
1450                 if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 416, NULL, NULL, &tdata) == PJ_SUCCESS) {
1451                         ast_sip_session_send_response(invite->session, tdata);
1452                 } else  {
1453                         pjsip_inv_terminate(invite->session->inv_session, 416, PJ_TRUE);
1454                 }
1455                 return 0;
1456         case SIP_GET_DEST_EXTEN_NOT_FOUND:
1457         case SIP_GET_DEST_EXTEN_PARTIAL:
1458         default:
1459                 ast_log(LOG_NOTICE, "Call from '%s' (%s:%s:%d) to extension '%s' rejected because extension not found in context '%s'.\n",
1460                         ast_sorcery_object_get_id(invite->session->endpoint), invite->rdata->tp_info.transport->type_name, invite->rdata->pkt_info.src_name,
1461                         invite->rdata->pkt_info.src_port, invite->session->exten, invite->session->endpoint->context);
1462
1463                 if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 404, NULL, NULL, &tdata) == PJ_SUCCESS) {
1464                         ast_sip_session_send_response(invite->session, tdata);
1465                 } else  {
1466                         pjsip_inv_terminate(invite->session->inv_session, 404, PJ_TRUE);
1467                 }
1468                 return 0;
1469         };
1470
1471         if ((sdp_info = pjsip_rdata_get_sdp_info(invite->rdata)) && (sdp_info->sdp_err == PJ_SUCCESS) && sdp_info->sdp) {
1472                 if (handle_incoming_sdp(invite->session, sdp_info->sdp)) {
1473                         if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 488, NULL, NULL, &tdata) == PJ_SUCCESS) {
1474                                 ast_sip_session_send_response(invite->session, tdata);
1475                         } else  {
1476                                 pjsip_inv_terminate(invite->session->inv_session, 488, PJ_TRUE);
1477                         }
1478                         return 0;
1479                 }
1480                 /* We are creating a local SDP which is an answer to their offer */
1481                 local = create_local_sdp(invite->session->inv_session, invite->session, sdp_info->sdp);
1482         } else {
1483                 /* We are creating a local SDP which is an offer */
1484                 local = create_local_sdp(invite->session->inv_session, invite->session, NULL);
1485         }
1486
1487         /* If we were unable to create a local SDP terminate the session early, it won't go anywhere */
1488         if (!local) {
1489                 if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 500, NULL, NULL, &tdata) == PJ_SUCCESS) {
1490                         ast_sip_session_send_response(invite->session, tdata);
1491                 } else  {
1492                         pjsip_inv_terminate(invite->session->inv_session, 500, PJ_TRUE);
1493                 }
1494                 return 0;
1495         } else {
1496                 pjsip_inv_set_local_sdp(invite->session->inv_session, local);
1497                 pjmedia_sdp_neg_set_prefer_remote_codec_order(invite->session->inv_session->neg, PJ_FALSE);
1498 #ifdef PJMEDIA_SDP_NEG_ANSWER_MULTIPLE_CODECS
1499                 pjmedia_sdp_neg_set_answer_multiple_codecs(invite->session->inv_session->neg, PJ_TRUE);
1500 #endif
1501         }
1502
1503         pjsip_timer_setting_default(&timer);
1504         timer.min_se = invite->session->endpoint->extensions.timer.min_se;
1505         timer.sess_expires = invite->session->endpoint->extensions.timer.sess_expires;
1506         pjsip_timer_init_session(invite->session->inv_session, &timer);
1507
1508         /* At this point, we've verified what we can, so let's go ahead and send a 100 Trying out */
1509         if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 100, NULL, NULL, &tdata) != PJ_SUCCESS) {
1510                 pjsip_inv_terminate(invite->session->inv_session, 500, PJ_TRUE);
1511                 return 0;
1512         }
1513         ast_sip_session_send_response(invite->session, tdata);
1514
1515         handle_incoming_request(invite->session, invite->rdata);
1516
1517         return 0;
1518 }
1519
1520 static void handle_new_invite_request(pjsip_rx_data *rdata)
1521 {
1522         RAII_VAR(struct ast_sip_endpoint *, endpoint,
1523                         ast_pjsip_rdata_get_endpoint(rdata), ao2_cleanup);
1524         pjsip_tx_data *tdata = NULL;
1525         pjsip_inv_session *inv_session = NULL;
1526         RAII_VAR(struct ast_sip_session *, session, NULL, ao2_cleanup);
1527         struct new_invite *invite;
1528
1529         ast_assert(endpoint != NULL);
1530
1531         inv_session = pre_session_setup(rdata, endpoint);
1532         if (!inv_session) {
1533                 /* pre_session_setup() returns a response on failure */
1534                 return;
1535         }
1536
1537         session = ast_sip_session_alloc(endpoint, inv_session);
1538         if (!session) {
1539                 if (pjsip_inv_initial_answer(inv_session, rdata, 500, NULL, NULL, &tdata) == PJ_SUCCESS) {
1540                         pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1541                 } else {
1542                         pjsip_inv_send_msg(inv_session, tdata);
1543                 }
1544                 return;
1545         }
1546
1547         invite = new_invite_alloc(session, rdata);
1548         if (!invite || ast_sip_push_task(session->serializer, new_invite, invite)) {
1549                 if (pjsip_inv_initial_answer(inv_session, rdata, 500, NULL, NULL, &tdata) == PJ_SUCCESS) {
1550                         pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1551                 } else {
1552                         pjsip_inv_send_msg(inv_session, tdata);
1553                 }
1554                 ao2_ref(session, -1);
1555                 ao2_cleanup(invite);
1556                 return;
1557         }
1558 }
1559
1560 static pj_bool_t does_method_match(const pj_str_t *message_method, const char *supplement_method)
1561 {
1562         pj_str_t method;
1563
1564         if (ast_strlen_zero(supplement_method)) {
1565                 return PJ_TRUE;
1566         }
1567
1568         pj_cstr(&method, supplement_method);
1569
1570         return pj_stristr(&method, message_method) ? PJ_TRUE : PJ_FALSE;
1571 }
1572
1573 static pj_bool_t has_supplement(const struct ast_sip_session *session, const pjsip_rx_data *rdata)
1574 {
1575         struct ast_sip_session_supplement *supplement;
1576         struct pjsip_method *method = &rdata->msg_info.msg->line.req.method;
1577
1578         if (!session) {
1579                 return PJ_FALSE;
1580         }
1581
1582         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1583                 if (does_method_match(&method->name, supplement->method)) {
1584                         return PJ_TRUE;
1585                 }
1586         }
1587         return PJ_FALSE;
1588 }
1589 /*!
1590  * \brief Called when a new SIP request comes into PJSIP
1591  *
1592  * This function is called under two circumstances
1593  * 1) An out-of-dialog request is received by PJSIP
1594  * 2) An in-dialog request that the inv_session layer does not
1595  *    handle is received (such as an in-dialog INFO)
1596  *
1597  * In all cases, there is very little we actually do in this function
1598  * 1) For requests we don't handle, we return PJ_FALSE
1599  * 2) For new INVITEs, throw the work into the SIP threadpool to be done
1600  *    there to free up the thread(s) handling incoming requests
1601  * 3) For in-dialog requests we handle, we defer handling them until the
1602  *    on_inv_state_change() callback instead (where we will end up putting
1603  *    them into the threadpool).
1604  */
1605 static pj_bool_t session_on_rx_request(pjsip_rx_data *rdata)
1606 {
1607         pj_status_t handled = PJ_FALSE;
1608         pjsip_dialog *dlg = pjsip_rdata_get_dlg(rdata);
1609         pjsip_inv_session *inv_session;
1610
1611         switch (rdata->msg_info.msg->line.req.method.id) {
1612         case PJSIP_INVITE_METHOD:
1613                 if (dlg) {
1614                         ast_log(LOG_WARNING, "on_rx_request called for INVITE in mid-dialog?\n");
1615                         break;
1616                 }
1617                 handled = PJ_TRUE;
1618                 handle_new_invite_request(rdata);
1619                 break;
1620         default:
1621                 /* Handle other in-dialog methods if their supplements have been registered */
1622                 handled = dlg && (inv_session = pjsip_dlg_get_inv_session(dlg)) &&
1623                         has_supplement(inv_session->mod_data[session_module.id], rdata);
1624                 break;
1625         }
1626
1627         return handled;
1628 }
1629
1630 struct reschedule_reinvite_data {
1631         struct ast_sip_session *session;
1632         struct ast_sip_session_delayed_request *delay;
1633 };
1634
1635 static struct reschedule_reinvite_data *reschedule_reinvite_data_alloc(
1636                 struct ast_sip_session *session, struct ast_sip_session_delayed_request *delay)
1637 {
1638         struct reschedule_reinvite_data *rrd = ast_malloc(sizeof(*rrd));
1639         if (!rrd) {
1640                 return NULL;
1641         }
1642         ao2_ref(session, +1);
1643         rrd->session = session;
1644         rrd->delay = delay;
1645         return rrd;
1646 }
1647
1648 static void reschedule_reinvite_data_destroy(struct reschedule_reinvite_data *rrd)
1649 {
1650         ao2_cleanup(rrd->session);
1651         ast_free(rrd->delay);
1652         ast_free(rrd);
1653 }
1654
1655 static int really_resend_reinvite(void *data)
1656 {
1657         RAII_VAR(struct reschedule_reinvite_data *, rrd, data, reschedule_reinvite_data_destroy);
1658
1659         return send_delayed_request(rrd->session, rrd->delay);
1660 }
1661
1662 static void resend_reinvite(pj_timer_heap_t *timer, pj_timer_entry *entry)
1663 {
1664         struct reschedule_reinvite_data *rrd = entry->user_data;
1665
1666         ast_sip_push_task(rrd->session->serializer, really_resend_reinvite, entry->user_data);
1667 }
1668
1669 static void reschedule_reinvite(struct ast_sip_session *session, ast_sip_session_response_cb on_response, pjsip_tx_data *tdata)
1670 {
1671         struct ast_sip_session_delayed_request *delay = delayed_request_alloc("INVITE",
1672                         NULL, NULL, on_response, tdata);
1673         pjsip_inv_session *inv = session->inv_session;
1674         struct reschedule_reinvite_data *rrd = reschedule_reinvite_data_alloc(session, delay);
1675         pj_time_val tv;
1676
1677         if (!rrd || !delay) {
1678                 return;
1679         }
1680
1681         tv.sec = 0;
1682         if (inv->role == PJSIP_ROLE_UAC) {
1683                 tv.msec = 2100 + ast_random() % 2000;
1684         } else {
1685                 tv.msec = ast_random() % 2000;
1686         }
1687
1688         pj_timer_entry_init(&session->rescheduled_reinvite, 0, rrd, resend_reinvite);
1689
1690         pjsip_endpt_schedule_timer(ast_sip_get_pjsip_endpoint(), &session->rescheduled_reinvite, &tv);
1691 }
1692
1693 static void __print_debug_details(const char *function, pjsip_inv_session *inv, pjsip_transaction *tsx, pjsip_event *e)
1694 {
1695         struct ast_sip_session *session;
1696         ast_debug(5, "Function %s called on event %s\n", function, pjsip_event_str(e->type));
1697         if (!inv) {
1698                 ast_debug(5, "Transaction %p does not belong to an inv_session?\n", tsx);
1699                 ast_debug(5, "The transaction state is %s\n", pjsip_tsx_state_str(tsx->state));
1700                 return;
1701         }
1702         session = inv->mod_data[session_module.id];
1703         if (!session) {
1704                 ast_debug(5, "inv_session %p has no ast session\n", inv);
1705         } else {
1706                 ast_debug(5, "The state change pertains to the session with %s\n",
1707                                 ast_sorcery_object_get_id(session->endpoint));
1708         }
1709         if (inv->invite_tsx) {
1710                 ast_debug(5, "The inv session still has an invite_tsx (%p)\n", inv->invite_tsx);
1711         } else {
1712                 ast_debug(5, "The inv session does NOT have an invite_tsx\n");
1713         }
1714         if (tsx) {
1715                 ast_debug(5, "The transaction involved in this state change is %p\n", tsx);
1716                 ast_debug(5, "The current transaction state is %s\n", pjsip_tsx_state_str(tsx->state));
1717                 ast_debug(5, "The transaction state change event is %s\n", pjsip_event_str(e->body.tsx_state.type));
1718         } else {
1719                 ast_debug(5, "There is no transaction involved in this state change\n");
1720         }
1721         ast_debug(5, "The current inv state is %s\n", pjsip_inv_state_name(inv->state));
1722 }
1723
1724 #define print_debug_details(inv, tsx, e) __print_debug_details(__PRETTY_FUNCTION__, (inv), (tsx), (e))
1725
1726 static void handle_incoming_request(struct ast_sip_session *session, pjsip_rx_data *rdata)
1727 {
1728         struct ast_sip_session_supplement *supplement;
1729         struct pjsip_request_line req = rdata->msg_info.msg->line.req;
1730
1731         ast_debug(3, "Method is %.*s\n", (int) pj_strlen(&req.method.name), pj_strbuf(&req.method.name));
1732         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1733                 if (supplement->incoming_request && does_method_match(&req.method.name, supplement->method)) {
1734                         if (supplement->incoming_request(session, rdata)) {
1735                                 break;
1736                         }
1737                 }
1738         }
1739 }
1740
1741 static void handle_incoming_response(struct ast_sip_session *session, pjsip_rx_data *rdata)
1742 {
1743         struct ast_sip_session_supplement *supplement;
1744         struct pjsip_status_line status = rdata->msg_info.msg->line.status;
1745
1746         ast_debug(3, "Response is %d %.*s\n", status.code, (int) pj_strlen(&status.reason),
1747                         pj_strbuf(&status.reason));
1748
1749         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1750                 if (supplement->incoming_response && does_method_match(&rdata->msg_info.cseq->method.name, supplement->method)) {
1751                         supplement->incoming_response(session, rdata);
1752                 }
1753         }
1754 }
1755
1756 static int handle_incoming(struct ast_sip_session *session, pjsip_rx_data *rdata)
1757 {
1758         ast_debug(3, "Received %s\n", rdata->msg_info.msg->type == PJSIP_REQUEST_MSG ?
1759                         "request" : "response");
1760
1761         if (rdata->msg_info.msg->type == PJSIP_REQUEST_MSG) {
1762                 handle_incoming_request(session, rdata);
1763         } else {
1764                 handle_incoming_response(session, rdata);
1765         }
1766
1767         return 0;
1768 }
1769
1770 static void handle_outgoing_request(struct ast_sip_session *session, pjsip_tx_data *tdata)
1771 {
1772         struct ast_sip_session_supplement *supplement;
1773         struct pjsip_request_line req = tdata->msg->line.req;
1774
1775         ast_debug(3, "Method is %.*s\n", (int) pj_strlen(&req.method.name), pj_strbuf(&req.method.name));
1776         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1777                 if (supplement->outgoing_request && does_method_match(&req.method.name, supplement->method)) {
1778                         supplement->outgoing_request(session, tdata);
1779                 }
1780         }
1781 }
1782
1783 static void handle_outgoing_response(struct ast_sip_session *session, pjsip_tx_data *tdata)
1784 {
1785         struct ast_sip_session_supplement *supplement;
1786         struct pjsip_status_line status = tdata->msg->line.status;
1787         pjsip_cseq_hdr *cseq = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_CSEQ, NULL);
1788         ast_debug(3, "Method is %.*s, Response is %d %.*s\n", (int) pj_strlen(&cseq->method.name),
1789                 pj_strbuf(&cseq->method.name), status.code, (int) pj_strlen(&status.reason),
1790                 pj_strbuf(&status.reason));
1791
1792         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1793                 if (supplement->outgoing_response && does_method_match(&cseq->method.name, supplement->method)) {
1794                         supplement->outgoing_response(session, tdata);
1795                 }
1796         }
1797 }
1798
1799 static void handle_outgoing(struct ast_sip_session *session, pjsip_tx_data *tdata)
1800 {
1801         ast_debug(3, "Sending %s\n", tdata->msg->type == PJSIP_REQUEST_MSG ?
1802                         "request" : "response");
1803         if (tdata->msg->type == PJSIP_REQUEST_MSG) {
1804                 handle_outgoing_request(session, tdata);
1805         } else {
1806                 handle_outgoing_response(session, tdata);
1807         }
1808 }
1809
1810 static int session_end(struct ast_sip_session *session)
1811 {
1812         struct ast_sip_session_supplement *iter;
1813
1814         /* Stop the scheduled termination */
1815         if (pj_timer_heap_cancel(pjsip_endpt_get_timer_heap(ast_sip_get_pjsip_endpoint()), &session->scheduled_termination)) {
1816                 ao2_ref(session, -1);
1817         }
1818
1819         /* Session is dead. Let's get rid of the reference to the session */
1820         AST_LIST_TRAVERSE(&session->supplements, iter, next) {
1821                 if (iter->session_end) {
1822                         iter->session_end(session);
1823                 }
1824         }
1825
1826         session->inv_session->mod_data[session_module.id] = NULL;
1827         ast_sip_dialog_set_serializer(session->inv_session->dlg, NULL);
1828         ast_sip_dialog_set_endpoint(session->inv_session->dlg, NULL);
1829         ao2_cleanup(session);
1830         return 0;
1831 }
1832
1833 static void session_inv_on_state_changed(pjsip_inv_session *inv, pjsip_event *e)
1834 {
1835         struct ast_sip_session *session = inv->mod_data[session_module.id];
1836         pjsip_event_id_e type;
1837
1838         if (e) {
1839                 print_debug_details(inv, NULL, e);
1840                 type = e->type;
1841         } else {
1842                 type = PJSIP_EVENT_UNKNOWN;
1843         }
1844
1845         if (!session) {
1846                 return;
1847         }
1848
1849         switch(type) {
1850         case PJSIP_EVENT_TX_MSG:
1851                 handle_outgoing(session, e->body.tx_msg.tdata);
1852                 break;
1853         case PJSIP_EVENT_RX_MSG:
1854                 handle_incoming(session, e->body.rx_msg.rdata);
1855                 break;
1856         case PJSIP_EVENT_TSX_STATE:
1857                 ast_debug(3, "Source of transaction state change is %s\n", pjsip_event_str(e->body.tsx_state.type));
1858                 /* Transaction state changes are prompted by some other underlying event. */
1859                 switch(e->body.tsx_state.type) {
1860                 case PJSIP_EVENT_TX_MSG:
1861                         handle_outgoing(session, e->body.tsx_state.src.tdata);
1862                         break;
1863                 case PJSIP_EVENT_RX_MSG:
1864                         handle_incoming(session, e->body.tsx_state.src.rdata);
1865                         break;
1866                 case PJSIP_EVENT_TRANSPORT_ERROR:
1867                 case PJSIP_EVENT_TIMER:
1868                 case PJSIP_EVENT_USER:
1869                 case PJSIP_EVENT_UNKNOWN:
1870                 case PJSIP_EVENT_TSX_STATE:
1871                         /* Inception? */
1872                         break;
1873                 }
1874                 break;
1875         case PJSIP_EVENT_TRANSPORT_ERROR:
1876         case PJSIP_EVENT_TIMER:
1877         case PJSIP_EVENT_UNKNOWN:
1878         case PJSIP_EVENT_USER:
1879         default:
1880                 break;
1881         }
1882
1883         if (inv->state == PJSIP_INV_STATE_DISCONNECTED) {
1884                 session_end(session);
1885         }
1886 }
1887
1888 static void session_inv_on_new_session(pjsip_inv_session *inv, pjsip_event *e)
1889 {
1890         /* XXX STUB */
1891 }
1892
1893 static void session_inv_on_tsx_state_changed(pjsip_inv_session *inv, pjsip_transaction *tsx, pjsip_event *e)
1894 {
1895         ast_sip_session_response_cb cb;
1896         struct ast_sip_session *session = inv->mod_data[session_module.id];
1897         print_debug_details(inv, tsx, e);
1898         if (!session) {
1899                 /* Transaction likely timed out after the call was hung up. Just
1900                  * ignore such transaction changes
1901                  */
1902                 return;
1903         }
1904         switch (e->body.tsx_state.type) {
1905         case PJSIP_EVENT_TX_MSG:
1906                 /* When we create an outgoing request, we do not have access to the transaction that
1907                  * is created. Instead, We have to place transaction-specific data in the tdata. Here,
1908                  * we transfer the data into the transaction. This way, when we receive a response, we
1909                  * can dig this data out again
1910                  */
1911                 tsx->mod_data[session_module.id] = e->body.tsx_state.src.tdata->mod_data[session_module.id];
1912                 break;
1913         case PJSIP_EVENT_RX_MSG:
1914                 if (tsx->method.id == PJSIP_INVITE_METHOD) {
1915                         if (tsx->role == PJSIP_ROLE_UAC) {
1916                                 if (tsx->state == PJSIP_TSX_STATE_COMPLETED) {
1917                                         /* This means we got a non 2XX final response to our outgoing INVITE */
1918                                         if (tsx->status_code == PJSIP_SC_REQUEST_PENDING) {
1919                                                 reschedule_reinvite(session, tsx->mod_data[session_module.id], tsx->last_tx);
1920                                                 return;
1921                                         } else if (inv->state == PJSIP_INV_STATE_CONFIRMED &&
1922                                                    tsx->status_code != 488) {
1923                                                 /* Other reinvite failures (except 488) result in destroying the session. */
1924                                                 pjsip_tx_data *tdata;
1925                                                 if (pjsip_inv_end_session(inv, 500, NULL, &tdata) == PJ_SUCCESS) {
1926                                                         ast_sip_session_send_request(session, tdata);
1927                                                 }
1928                                         }
1929                                 } else if (tsx->state == PJSIP_TSX_STATE_TERMINATED) {
1930                                         if (inv->cancelling && tsx->status_code == PJSIP_SC_OK) {
1931                                                 /* This is a race condition detailed in RFC 5407 section 3.1.2.
1932                                                  * We sent a CANCEL at the same time that the UAS sent us a 200 OK for
1933                                                  * the original INVITE. As a result, we have now received a 200 OK for
1934                                                  * a cancelled call. Our role is to immediately send a BYE to end the
1935                                                  * dialog.
1936                                                  */
1937                                                 pjsip_tx_data *tdata;
1938
1939                                                 if (pjsip_inv_end_session(inv, 500, NULL, &tdata) == PJ_SUCCESS) {
1940                                                         ast_sip_session_send_request(session, tdata);
1941                                                 }
1942                                         }
1943                                 }
1944                         }
1945                 } else {
1946                         if (tsx->role == PJSIP_ROLE_UAS && tsx->state == PJSIP_TSX_STATE_TRYING) {
1947                                 handle_incoming_request(session, e->body.tsx_state.src.rdata);
1948                         }
1949                 }
1950                 if ((cb = ast_sip_mod_data_get(tsx->mod_data, session_module.id,
1951                                                MOD_DATA_ON_RESPONSE))) {
1952                         cb(session, e->body.tsx_state.src.rdata);
1953                 }
1954         case PJSIP_EVENT_TRANSPORT_ERROR:
1955         case PJSIP_EVENT_TIMER:
1956         case PJSIP_EVENT_USER:
1957         case PJSIP_EVENT_UNKNOWN:
1958         case PJSIP_EVENT_TSX_STATE:
1959                 /* Inception? */
1960                 break;
1961         }
1962
1963         /* Terminated INVITE transactions always should result in queuing delayed requests,
1964          * no matter what event caused the transaction to terminate
1965          */
1966         if (tsx->method.id == PJSIP_INVITE_METHOD && tsx->state == PJSIP_TSX_STATE_TERMINATED) {
1967                 queue_delayed_request(session);
1968         }
1969 }
1970
1971 static int add_sdp_streams(void *obj, void *arg, void *data, int flags)
1972 {
1973         struct ast_sip_session_media *session_media = obj;
1974         pjmedia_sdp_session *answer = arg;
1975         struct ast_sip_session *session = data;
1976         struct ast_sip_session_sdp_handler *handler = session_media->handler;
1977         RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
1978
1979         if (handler) {
1980                 /* if an already assigned handler does not handle the session_media or reports a catastrophic error, fail */
1981                 if (handler->create_outgoing_sdp_stream(session, session_media, answer) <= 0) {
1982                         return 0;
1983                 }
1984                 return CMP_MATCH;
1985         }
1986
1987         handler_list = ao2_find(sdp_handlers, session_media->stream_type, OBJ_KEY);
1988         if (!handler_list) {
1989                 return CMP_MATCH;
1990         }
1991
1992         /* no handler for this stream type and we have a list to search */
1993         AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
1994                 int res = handler->create_outgoing_sdp_stream(session, session_media, answer);
1995                 if (res < 0) {
1996                         /* catastrophic error */
1997                         return 0;
1998                 }
1999                 if (res > 0) {
2000                         /* handled */
2001                         return CMP_MATCH;
2002                 }
2003         }
2004
2005         /* streams that weren't handled won't be included in generated outbound SDP */
2006         return CMP_MATCH;
2007 }
2008
2009 static struct pjmedia_sdp_session *create_local_sdp(pjsip_inv_session *inv, struct ast_sip_session *session, const pjmedia_sdp_session *offer)
2010 {
2011         RAII_VAR(struct ao2_iterator *, successful, NULL, ao2_iterator_cleanup);
2012         static const pj_str_t STR_IN = { "IN", 2 };
2013         static const pj_str_t STR_IP4 = { "IP4", 3 };
2014         static const pj_str_t STR_IP6 = { "IP6", 3 };
2015         pjmedia_sdp_session *local;
2016
2017         if (!(local = PJ_POOL_ZALLOC_T(inv->pool_prov, pjmedia_sdp_session))) {
2018                 return NULL;
2019         }
2020
2021         if (!offer) {
2022                 local->origin.version = local->origin.id = (pj_uint32_t)(ast_random());
2023         } else {
2024                 local->origin.version = offer->origin.version + 1;
2025                 local->origin.id = offer->origin.id;
2026         }
2027
2028         pj_strdup2(inv->pool, &local->origin.user, session->endpoint->media.sdpowner);
2029         local->origin.net_type = STR_IN;
2030         local->origin.addr_type = session->endpoint->media.rtp.ipv6 ? STR_IP6 : STR_IP4;
2031         local->origin.addr = *hostname;
2032         pj_strdup2(inv->pool, &local->name, session->endpoint->media.sdpsession);
2033
2034         /* Now let the handlers add streams of various types, pjmedia will automatically reorder the media streams for us */
2035         successful = ao2_callback_data(session->media, OBJ_MULTIPLE, add_sdp_streams, local, session);
2036         if (!successful || ao2_iterator_count(successful) != ao2_container_count(session->media)) {
2037                 /* Something experienced a catastrophic failure */
2038                 return NULL;
2039         }
2040
2041         /* Use the connection details of the first media stream if possible for SDP level */
2042         if (local->media_count) {
2043                 local->conn = local->media[0]->conn;
2044         }
2045
2046         return local;
2047 }
2048
2049 static void session_inv_on_rx_offer(pjsip_inv_session *inv, const pjmedia_sdp_session *offer)
2050 {
2051         struct ast_sip_session *session = inv->mod_data[session_module.id];
2052         pjmedia_sdp_session *answer;
2053
2054         if (handle_incoming_sdp(session, offer)) {
2055                 return;
2056         }
2057
2058         if ((answer = create_local_sdp(inv, session, offer))) {
2059                 pjsip_inv_set_sdp_answer(inv, answer);
2060         }
2061 }
2062
2063 #if 0
2064 static void session_inv_on_create_offer(pjsip_inv_session *inv, pjmedia_sdp_session **p_offer)
2065 {
2066         /* XXX STUB */
2067 }
2068 #endif
2069
2070 static void session_inv_on_media_update(pjsip_inv_session *inv, pj_status_t status)
2071 {
2072         struct ast_sip_session *session = inv->mod_data[session_module.id];
2073         const pjmedia_sdp_session *local, *remote;
2074
2075         if (!session->channel) {
2076                 /* If we don't have a channel. We really don't care about media updates.
2077                  * Just ignore
2078                  */
2079                 return;
2080         }
2081
2082         if ((status != PJ_SUCCESS) || (pjmedia_sdp_neg_get_active_local(inv->neg, &local) != PJ_SUCCESS) ||
2083                 (pjmedia_sdp_neg_get_active_remote(inv->neg, &remote) != PJ_SUCCESS)) {
2084                 ast_channel_hangupcause_set(session->channel, AST_CAUSE_BEARERCAPABILITY_NOTAVAIL);
2085                 ast_queue_hangup(session->channel);
2086                 return;
2087         }
2088
2089         handle_negotiated_sdp(session, local, remote);
2090 }
2091
2092 static pjsip_redirect_op session_inv_on_redirected(pjsip_inv_session *inv, const pjsip_uri *target, const pjsip_event *e)
2093 {
2094         struct ast_sip_session *session = inv->mod_data[session_module.id];
2095         const pjsip_sip_uri *uri;
2096
2097         if (session->endpoint->redirect_method == AST_SIP_REDIRECT_URI_PJSIP) {
2098                 return PJSIP_REDIRECT_ACCEPT;
2099         }
2100
2101         if (!PJSIP_URI_SCHEME_IS_SIP(target) && !PJSIP_URI_SCHEME_IS_SIPS(target)) {
2102                 return PJSIP_REDIRECT_STOP;
2103         }
2104
2105         uri = pjsip_uri_get_uri(target);
2106
2107         if (session->endpoint->redirect_method == AST_SIP_REDIRECT_USER) {
2108                 char exten[AST_MAX_EXTENSION];
2109
2110                 ast_copy_pj_str(exten, &uri->user, sizeof(exten));
2111                 ast_channel_call_forward_set(session->channel, exten);
2112         } else if (session->endpoint->redirect_method == AST_SIP_REDIRECT_URI_CORE) {
2113                 char target_uri[PJSIP_MAX_URL_SIZE];
2114                 /* PJSIP/ + endpoint length + / + max URL size */
2115                 char forward[8 + strlen(ast_sorcery_object_get_id(session->endpoint)) + PJSIP_MAX_URL_SIZE];
2116
2117                 pjsip_uri_print(PJSIP_URI_IN_REQ_URI, uri, target_uri, sizeof(target_uri));
2118                 sprintf(forward, "PJSIP/%s/%s", ast_sorcery_object_get_id(session->endpoint), target_uri);
2119                 ast_channel_call_forward_set(session->channel, forward);
2120         }
2121
2122         return PJSIP_REDIRECT_STOP;
2123 }
2124
2125 static pjsip_inv_callback inv_callback = {
2126         .on_state_changed = session_inv_on_state_changed,
2127         .on_new_session = session_inv_on_new_session,
2128         .on_tsx_state_changed = session_inv_on_tsx_state_changed,
2129         .on_rx_offer = session_inv_on_rx_offer,
2130         .on_media_update = session_inv_on_media_update,
2131         .on_redirected = session_inv_on_redirected,
2132 };
2133
2134 /*! \brief Hook for modifying outgoing messages with SDP to contain the proper address information */
2135 static void session_outgoing_nat_hook(pjsip_tx_data *tdata, struct ast_sip_transport *transport)
2136 {
2137         struct ast_sip_nat_hook *hook = ast_sip_mod_data_get(
2138                 tdata->mod_data, session_module.id, MOD_DATA_NAT_HOOK);
2139         struct pjmedia_sdp_session *sdp;
2140         int stream;
2141
2142         /* SDP produced by us directly will never be multipart */
2143         if (hook || !tdata->msg->body || pj_stricmp2(&tdata->msg->body->content_type.type, "application") ||
2144                 pj_stricmp2(&tdata->msg->body->content_type.subtype, "sdp") || ast_strlen_zero(transport->external_media_address)) {
2145                 return;
2146         }
2147
2148         sdp = tdata->msg->body->data;
2149
2150         if (sdp->conn) {
2151                 char host[NI_MAXHOST];
2152                 struct ast_sockaddr addr = { { 0, } };
2153
2154                 ast_copy_pj_str(host, &sdp->conn->addr, sizeof(host));
2155                 ast_sockaddr_parse(&addr, host, PARSE_PORT_FORBID);
2156
2157                 if (ast_apply_ha(transport->localnet, &addr) != AST_SENSE_ALLOW) {
2158                         pj_strdup2(tdata->pool, &sdp->conn->addr, transport->external_media_address);
2159                 }
2160         }
2161
2162         for (stream = 0; stream < sdp->media_count; ++stream) {
2163                 /* See if there are registered handlers for this media stream type */
2164                 char media[20];
2165                 struct ast_sip_session_sdp_handler *handler;
2166                 RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
2167
2168                 /* We need a null-terminated version of the media string */
2169                 ast_copy_pj_str(media, &sdp->media[stream]->desc.media, sizeof(media));
2170
2171                 handler_list = ao2_find(sdp_handlers, media, OBJ_KEY);
2172                 if (!handler_list) {
2173                         ast_debug(1, "No registered SDP handlers for media type '%s'\n", media);
2174                         continue;
2175                 }
2176                 AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
2177                         if (handler->change_outgoing_sdp_stream_media_address) {
2178                                 handler->change_outgoing_sdp_stream_media_address(tdata, sdp->media[stream], transport);
2179                         }
2180                 }
2181         }
2182
2183         /* We purposely do this so that the hook will not be invoked multiple times, ie: if a retransmit occurs */
2184         ast_sip_mod_data_set(tdata->pool, tdata->mod_data, session_module.id, MOD_DATA_NAT_HOOK, nat_hook);
2185 }
2186
2187 static int load_module(void)
2188 {
2189         pjsip_endpoint *endpt;
2190         if (!ast_sip_get_sorcery() || !ast_sip_get_pjsip_endpoint()) {
2191                 return AST_MODULE_LOAD_DECLINE;
2192         }
2193         if (!(nat_hook = ast_sorcery_alloc(ast_sip_get_sorcery(), "nat_hook", NULL))) {
2194                 return AST_MODULE_LOAD_DECLINE;
2195         }
2196         nat_hook->outgoing_external_message = session_outgoing_nat_hook;
2197         ast_sorcery_create(ast_sip_get_sorcery(), nat_hook);
2198         sdp_handlers = ao2_container_alloc(SDP_HANDLER_BUCKETS,
2199                         sdp_handler_list_hash, sdp_handler_list_cmp);
2200         if (!sdp_handlers) {
2201                 return AST_MODULE_LOAD_DECLINE;
2202         }
2203         endpt = ast_sip_get_pjsip_endpoint();
2204         pjsip_inv_usage_init(endpt, &inv_callback);
2205         pjsip_100rel_init_module(endpt);
2206         pjsip_timer_init_module(endpt);
2207         hostname = pj_gethostname();
2208         if (ast_sip_register_service(&session_module)) {
2209                 return AST_MODULE_LOAD_DECLINE;
2210         }
2211         ast_sip_register_service(&session_reinvite_module);
2212
2213         ast_module_ref(ast_module_info->self);
2214
2215         return AST_MODULE_LOAD_SUCCESS;
2216 }
2217
2218 static int unload_module(void)
2219 {
2220         /* This will never get called as this module can't be unloaded */
2221         return 0;
2222 }
2223
2224 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "PJSIP Session resource",
2225                 .load = load_module,
2226                 .unload = unload_module,
2227                 .load_pri = AST_MODPRI_APP_DEPEND,
2228                );