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 #include "asterisk/features_config.h"
  47 #include "asterisk/pickup.h"
  48
  49 #define SDP_HANDLER_BUCKETS 11
  50
  51 #define MOD_DATA_ON_RESPONSE "on_response"
  52 #define MOD_DATA_NAT_HOOK "nat_hook"
  53
  54 /* Hostname used for origin line within SDP */
  55 static const pj_str_t *hostname;
  56
  57 /* Some forward declarations */
  58 static void handle_incoming_request(struct ast_sip_session *session, pjsip_rx_data *rdata);
  59 static void handle_incoming_response(struct ast_sip_session *session, pjsip_rx_data *rdata);
  60 static int handle_incoming(struct ast_sip_session *session, pjsip_rx_data *rdata);
  61 static void handle_outgoing_request(struct ast_sip_session *session, pjsip_tx_data *tdata);
  62 static void handle_outgoing_response(struct ast_sip_session *session, pjsip_tx_data *tdata);
  63 static void handle_outgoing(struct ast_sip_session *session, pjsip_tx_data *tdata);
  64
  65 /*! \brief NAT hook for modifying outgoing messages with SDP */
  66 static struct ast_sip_nat_hook *nat_hook;
  67
  68 /*!
  69  * \brief Registered SDP stream handlers
  70  *
  71  * This container is keyed on stream types. Each
  72  * object in the container is a linked list of
  73  * handlers for the stream type.
  74  */
  75 static struct ao2_container *sdp_handlers;
  76
  77 /*!
  78  * These are the objects in the sdp_handlers container
  79  */
  80 struct sdp_handler_list {
  81         /* The list of handlers to visit */
  82         AST_LIST_HEAD_NOLOCK(, ast_sip_session_sdp_handler) list;
  83         /* The handlers in this list handle streams of this type */
  84         char stream_type[1];
  85 };
  86
  87 static struct pjmedia_sdp_session *create_local_sdp(pjsip_inv_session *inv, struct ast_sip_session *session, const pjmedia_sdp_session *offer);
  88
  89 static int sdp_handler_list_hash(const void *obj, int flags)
  90 {
  91         const struct sdp_handler_list *handler_list = obj;
  92         const char *stream_type = flags & OBJ_KEY ? obj : handler_list->stream_type;
  93
  94         return ast_str_hash(stream_type);
  95 }
  96
  97 static int sdp_handler_list_cmp(void *obj, void *arg, int flags)
  98 {
  99         struct sdp_handler_list *handler_list1 = obj;
 100         struct sdp_handler_list *handler_list2 = arg;
 101         const char *stream_type2 = flags & OBJ_KEY ? arg : handler_list2->stream_type;
 102
 103         return strcmp(handler_list1->stream_type, stream_type2) ? 0 : CMP_MATCH | CMP_STOP;
 104 }
 105
 106 static int session_media_hash(const void *obj, int flags)
 107 {
 108         const struct ast_sip_session_media *session_media = obj;
 109         const char *stream_type = flags & OBJ_KEY ? obj : session_media->stream_type;
 110
 111         return ast_str_hash(stream_type);
 112 }
 113
 114 static int session_media_cmp(void *obj, void *arg, int flags)
 115 {
 116         struct ast_sip_session_media *session_media1 = obj;
 117         struct ast_sip_session_media *session_media2 = arg;
 118         const char *stream_type2 = flags & OBJ_KEY ? arg : session_media2->stream_type;
 119
 120         return strcmp(session_media1->stream_type, stream_type2) ? 0 : CMP_MATCH | CMP_STOP;
 121 }
 122
 123 int ast_sip_session_register_sdp_handler(struct ast_sip_session_sdp_handler *handler, const char *stream_type)
 124 {
 125         RAII_VAR(struct sdp_handler_list *, handler_list,
 126                         ao2_find(sdp_handlers, stream_type, OBJ_KEY), ao2_cleanup);
 127         SCOPED_AO2LOCK(lock, sdp_handlers);
 128
 129         if (handler_list) {
 130                 struct ast_sip_session_sdp_handler *iter;
 131                 /* Check if this handler is already registered for this stream type */
 132                 AST_LIST_TRAVERSE(&handler_list->list, iter, next) {
 133                         if (!strcmp(iter->id, handler->id)) {
 134                                 ast_log(LOG_WARNING, "Handler '%s' already registered for stream type '%s'.\n", handler->id, stream_type);
 135                                 return -1;
 136                         }
 137                 }
 138                 AST_LIST_INSERT_TAIL(&handler_list->list, handler, next);
 139                 ast_debug(1, "Registered SDP stream handler '%s' for stream type '%s'\n", handler->id, stream_type);
 140                 ast_module_ref(ast_module_info->self);
 141                 return 0;
 142         }
 143
 144         /* No stream of this type has been registered yet, so we need to create a new list */
 145         handler_list = ao2_alloc(sizeof(*handler_list) + strlen(stream_type), NULL);
 146         if (!handler_list) {
 147                 return -1;
 148         }
 149         /* Safe use of strcpy */
 150         strcpy(handler_list->stream_type, stream_type);
 151         AST_LIST_HEAD_INIT_NOLOCK(&handler_list->list);
 152         AST_LIST_INSERT_TAIL(&handler_list->list, handler, next);
 153         if (!ao2_link(sdp_handlers, handler_list)) {
 154                 return -1;
 155         }
 156         ast_debug(1, "Registered SDP stream handler '%s' for stream type '%s'\n", handler->id, stream_type);
 157         ast_module_ref(ast_module_info->self);
 158         return 0;
 159 }
 160
 161 static int remove_handler(void *obj, void *arg, void *data, int flags)
 162 {
 163         struct sdp_handler_list *handler_list = obj;
 164         struct ast_sip_session_sdp_handler *handler = data;
 165         struct ast_sip_session_sdp_handler *iter;
 166         const char *stream_type = arg;
 167
 168         AST_LIST_TRAVERSE_SAFE_BEGIN(&handler_list->list, iter, next) {
 169                 if (!strcmp(iter->id, handler->id)) {
 170                         AST_LIST_REMOVE_CURRENT(next);
 171                         ast_debug(1, "Unregistered SDP stream handler '%s' for stream type '%s'\n", handler->id, stream_type);
 172                         ast_module_unref(ast_module_info->self);
 173                 }
 174         }
 175         AST_LIST_TRAVERSE_SAFE_END;
 176
 177         if (AST_LIST_EMPTY(&handler_list->list)) {
 178                 ast_debug(3, "No more handlers exist for stream type '%s'\n", stream_type);
 179                 return CMP_MATCH;
 180         } else {
 181                 return CMP_STOP;
 182         }
 183 }
 184
 185 void ast_sip_session_unregister_sdp_handler(struct ast_sip_session_sdp_handler *handler, const char *stream_type)
 186 {
 187         ao2_callback_data(sdp_handlers, OBJ_KEY | OBJ_UNLINK | OBJ_NODATA, remove_handler, (void *)stream_type, handler);
 188 }
 189
 190 static int validate_port_hash(const void *obj, int flags)
 191 {
 192         const int *port = obj;
 193         return *port;
 194 }
 195
 196 static int validate_port_cmp(void *obj, void *arg, int flags)
 197 {
 198         int *port1 = obj;
 199         int *port2 = arg;
 200
 201         return *port1 == *port2 ? CMP_MATCH | CMP_STOP : 0;
 202 }
 203
 204 struct bundle_assoc {
 205         int port;
 206         char tag[1];
 207 };
 208
 209 static int bundle_assoc_hash(const void *obj, int flags)
 210 {
 211         const struct bundle_assoc *assoc = obj;
 212         const char *tag = flags & OBJ_KEY ? obj : assoc->tag;
 213
 214         return ast_str_hash(tag);
 215 }
 216
 217 static int bundle_assoc_cmp(void *obj, void *arg, int flags)
 218 {
 219         struct bundle_assoc *assoc1 = obj;
 220         struct bundle_assoc *assoc2 = arg;
 221         const char *tag2 = flags & OBJ_KEY ? arg : assoc2->tag;
 222
 223         return strcmp(assoc1->tag, tag2) ? 0 : CMP_MATCH | CMP_STOP;
 224 }
 225
 226 /* return must be ast_freed */
 227 static pjmedia_sdp_attr *media_get_mid(pjmedia_sdp_media *media)
 228 {
 229         pjmedia_sdp_attr *attr = pjmedia_sdp_media_find_attr2(media, "mid", NULL);
 230         if (!attr) {
 231                 return NULL;
 232         }
 233
 234         return attr;
 235 }
 236
 237 static int get_bundle_port(const pjmedia_sdp_session *sdp, const char *mid)
 238 {
 239         int i;
 240         for (i = 0; i < sdp->media_count; ++i) {
 241                 pjmedia_sdp_attr *mid_attr = media_get_mid(sdp->media[i]);
 242                 if (mid_attr && !pj_strcmp2(&mid_attr->value, mid)) {
 243                         return sdp->media[i]->desc.port;
 244                 }
 245         }
 246
 247         return -1;
 248 }
 249
 250 static int validate_incoming_sdp(const pjmedia_sdp_session *sdp)
 251 {
 252         int i;
 253         RAII_VAR(struct ao2_container *, portlist, ao2_container_alloc(5, validate_port_hash, validate_port_cmp), ao2_cleanup);
 254         RAII_VAR(struct ao2_container *, bundle_assoc_list, ao2_container_alloc(5, bundle_assoc_hash, bundle_assoc_cmp), ao2_cleanup);
 255
 256         /* check for bundles (for websocket RTP multiplexing, there can be more than one) */
 257         for (i = 0; i < sdp->attr_count; ++i) {
 258                 char *bundle_list;
 259                 int bundle_port = 0;
 260                 if (pj_stricmp2(&sdp->attr[i]->name, "group")) {
 261                         continue;
 262                 }
 263
 264                 /* check to see if this group is a bundle */
 265                 if (7 >= sdp->attr[i]->value.slen || pj_strnicmp2(&sdp->attr[i]->value, "bundle ", 7)) {
 266                         continue;
 267                 }
 268
 269                 bundle_list = ast_alloca(sdp->attr[i]->value.slen - 6);
 270                 strncpy(bundle_list, sdp->attr[i]->value.ptr + 7, sdp->attr[i]->value.slen - 7);
 271                 bundle_list[sdp->attr[i]->value.slen - 7] = '\0';
 272                 while (bundle_list) {
 273                         char *item;
 274                         RAII_VAR(struct bundle_assoc *, assoc, NULL, ao2_cleanup);
 275                         item = strsep(&bundle_list, " ,");
 276                         if (!bundle_port) {
 277                                 RAII_VAR(int *, port, ao2_alloc(sizeof(int), NULL), ao2_cleanup);
 278                                 RAII_VAR(int *, port_match, NULL, ao2_cleanup);
 279                                 bundle_port = get_bundle_port(sdp, item);
 280                                 if (bundle_port < 0) {
 281                                         return -1;
 282                                 }
 283                                 port_match = ao2_find(portlist, &bundle_port, OBJ_KEY);
 284                                 if (port_match) {
 285                                         /* bundle port aready consumed by a different bundle */
 286                                         return -1;
 287                                 }
 288                                 *port = bundle_port;
 289                                 ao2_link(portlist, port);
 290                         }
 291                         assoc = ao2_alloc(sizeof(*assoc) + strlen(item), NULL);
 292                         if (!assoc) {
 293                                 return -1;
 294                         }
 295
 296                         /* safe use of strcpy */
 297                         strcpy(assoc->tag, item);
 298                         assoc->port = bundle_port;
 299                         ao2_link(bundle_assoc_list, assoc);
 300                 }
 301         }
 302
 303         /* validate all streams */
 304         for (i = 0; i < sdp->media_count; ++i) {
 305                 RAII_VAR(int *, port, ao2_alloc(sizeof(int), NULL), ao2_cleanup);
 306                 RAII_VAR(int *, port_match, NULL, ao2_cleanup);
 307
 308                 *port = sdp->media[i]->desc.port;
 309                 port_match = ao2_find(portlist, port, OBJ_KEY);
 310                 if (port_match) {
 311                         RAII_VAR(struct bundle_assoc *, assoc, NULL, ao2_cleanup);
 312                         pjmedia_sdp_attr *mid = media_get_mid(sdp->media[i]);
 313                         char *mid_val;
 314
 315                         if (!mid) {
 316                                 /* not part of a bundle */
 317                                 return -1;
 318                         }
 319
 320                         mid_val = ast_alloca(mid->value.slen + 1);
 321                         strncpy(mid_val, mid->value.ptr, mid->value.slen);
 322                         mid_val[mid->value.slen] = '\0';
 323
 324                         assoc = ao2_find(bundle_assoc_list, mid_val, OBJ_KEY);
 325                         if (!assoc || assoc->port != *port) {
 326                                 /* This port already exists elsewhere in the SDP
 327                                  * and is not an appropriate bundle port, fail
 328                                  * catastrophically */
 329                                 return -1;
 330                         }
 331                 }
 332                 ao2_link(portlist, port);
 333         }
 334         return 0;
 335 }
 336
 337 static int handle_incoming_sdp(struct ast_sip_session *session, const pjmedia_sdp_session *sdp)
 338 {
 339         int i;
 340
 341         if (validate_incoming_sdp(sdp)) {
 342                 return -1;
 343         }
 344
 345         for (i = 0; i < sdp->media_count; ++i) {
 346                 /* See if there are registered handlers for this media stream type */
 347                 char media[20];
 348                 struct ast_sip_session_sdp_handler *handler;
 349                 RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
 350                 RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
 351                 int res;
 352
 353                 /* We need a null-terminated version of the media string */
 354                 ast_copy_pj_str(media, &sdp->media[i]->desc.media, sizeof(media));
 355
 356                 session_media = ao2_find(session->media, media, OBJ_KEY);
 357                 if (!session_media) {
 358                         /* if the session_media doesn't exist, there weren't
 359                          * any handlers at the time of its creation */
 360                         continue;
 361                 }
 362
 363                 if (session_media->handler) {
 364                         handler = session_media->handler;
 365                         res = handler->negotiate_incoming_sdp_stream(session, session_media, sdp,
 366                                 sdp->media[i]);
 367                         if (res <= 0) {
 368                                 /* Catastrophic failure or ignored by assigned handler. Abort! */
 369                                 return -1;
 370                         }
 371                         /* Handled by this handler. Move to the next stream */
 372                         continue;
 373                 }
 374
 375                 handler_list = ao2_find(sdp_handlers, media, OBJ_KEY);
 376                 if (!handler_list) {
 377                         ast_debug(1, "No registered SDP handlers for media type '%s'\n", media);
 378                         continue;
 379                 }
 380                 AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
 381                         res = handler->negotiate_incoming_sdp_stream(session, session_media, sdp,
 382                                 sdp->media[i]);
 383                         if (res < 0) {
 384                                 /* Catastrophic failure. Abort! */
 385                                 return -1;
 386                         }
 387                         if (res > 0) {
 388                                 /* Handled by this handler. Move to the next stream */
 389                                 session_media->handler = handler;
 390                                 break;
 391                         }
 392                 }
 393         }
 394         return 0;
 395 }
 396
 397 struct handle_negotiated_sdp_cb {
 398         struct ast_sip_session *session;
 399         const pjmedia_sdp_session *local;
 400         const pjmedia_sdp_session *remote;
 401 };
 402
 403 static int handle_negotiated_sdp_session_media(void *obj, void *arg, int flags)
 404 {
 405         struct ast_sip_session_media *session_media = obj;
 406         struct handle_negotiated_sdp_cb *callback_data = arg;
 407         struct ast_sip_session *session = callback_data->session;
 408         const pjmedia_sdp_session *local = callback_data->local;
 409         const pjmedia_sdp_session *remote = callback_data->remote;
 410         int i;
 411
 412         for (i = 0; i < local->media_count; ++i) {
 413                 /* See if there are registered handlers for this media stream type */
 414                 char media[20];
 415                 struct ast_sip_session_sdp_handler *handler;
 416                 RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
 417                 int res;
 418
 419                 if (!remote->media[i]) {
 420                         continue;
 421                 }
 422
 423                 /* We need a null-terminated version of the media string */
 424                 ast_copy_pj_str(media, &local->media[i]->desc.media, sizeof(media));
 425
 426                 /* stream type doesn't match the one we're looking to fill */
 427                 if (strcasecmp(session_media->stream_type, media)) {
 428                         continue;
 429                 }
 430
 431                 handler = session_media->handler;
 432                 if (handler) {
 433                         res = handler->apply_negotiated_sdp_stream(session, session_media, local,
 434                                 local->media[i], remote, remote->media[i]);
 435                         if (res >= 0) {
 436                                 return CMP_MATCH;
 437                         }
 438                         return 0;
 439                 }
 440
 441                 handler_list = ao2_find(sdp_handlers, media, OBJ_KEY);
 442                 if (!handler_list) {
 443                         ast_debug(1, "No registered SDP handlers for media type '%s'\n", media);
 444                         continue;
 445                 }
 446                 AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
 447                         res = handler->apply_negotiated_sdp_stream(session, session_media, local,
 448                                 local->media[i], remote, remote->media[i]);
 449                         if (res < 0) {
 450                                 /* Catastrophic failure. Abort! */
 451                                 return 0;
 452                         }
 453                         if (res > 0) {
 454                                 /* Handled by this handler. Move to the next stream */
 455                                 session_media->handler = handler;
 456                                 return CMP_MATCH;
 457                         }
 458                 }
 459         }
 460         return CMP_MATCH;
 461 }
 462
 463 static int handle_negotiated_sdp(struct ast_sip_session *session, const pjmedia_sdp_session *local, const pjmedia_sdp_session *remote)
 464 {
 465         RAII_VAR(struct ao2_iterator *, successful, NULL, ao2_iterator_cleanup);
 466         struct handle_negotiated_sdp_cb callback_data = {
 467                 .session = session,
 468                 .local = local,
 469                 .remote = remote,
 470         };
 471
 472         successful = ao2_callback(session->media, OBJ_MULTIPLE, handle_negotiated_sdp_session_media, &callback_data);
 473         if (successful && ao2_iterator_count(successful) == ao2_container_count(session->media)) {
 474                 /* Nothing experienced a catastrophic failure */
 475                 ast_queue_frame(session->channel, &ast_null_frame);
 476                 return 0;
 477         }
 478         return -1;
 479 }
 480
 481 AST_RWLIST_HEAD_STATIC(session_supplements, ast_sip_session_supplement);
 482
 483 int ast_sip_session_register_supplement(struct ast_sip_session_supplement *supplement)
 484 {
 485         struct ast_sip_session_supplement *iter;
 486         int inserted = 0;
 487         SCOPED_LOCK(lock, &session_supplements, AST_RWLIST_WRLOCK, AST_RWLIST_UNLOCK);
 488
 489         AST_RWLIST_TRAVERSE_SAFE_BEGIN(&session_supplements, iter, next) {
 490                 if (iter->priority > supplement->priority) {
 491                         AST_RWLIST_INSERT_BEFORE_CURRENT(supplement, next);
 492                         inserted = 1;
 493                         break;
 494                 }
 495         }
 496         AST_RWLIST_TRAVERSE_SAFE_END;
 497
 498         if (!inserted) {
 499                 AST_RWLIST_INSERT_TAIL(&session_supplements, supplement, next);
 500         }
 501         ast_module_ref(ast_module_info->self);
 502         return 0;
 503 }
 504
 505 void ast_sip_session_unregister_supplement(struct ast_sip_session_supplement *supplement)
 506 {
 507         struct ast_sip_session_supplement *iter;
 508         SCOPED_LOCK(lock, &session_supplements, AST_RWLIST_WRLOCK, AST_RWLIST_UNLOCK);
 509         AST_RWLIST_TRAVERSE_SAFE_BEGIN(&session_supplements, iter, next) {
 510                 if (supplement == iter) {
 511                         AST_RWLIST_REMOVE_CURRENT(next);
 512                         ast_module_unref(ast_module_info->self);
 513                         break;
 514                 }
 515         }
 516         AST_RWLIST_TRAVERSE_SAFE_END;
 517 }
 518
 519 static struct ast_sip_session_supplement *supplement_dup(const struct ast_sip_session_supplement *src)
 520 {
 521         struct ast_sip_session_supplement *dst = ast_calloc(1, sizeof(*dst));
 522         if (!dst) {
 523                 return NULL;
 524         }
 525         /* Will need to revisit if shallow copy becomes an issue */
 526         *dst = *src;
 527         return dst;
 528 }
 529
 530 #define DATASTORE_BUCKETS 53
 531 #define MEDIA_BUCKETS 7
 532
 533 static void session_datastore_destroy(void *obj)
 534 {
 535         struct ast_datastore *datastore = obj;
 536
 537         /* Using the destroy function (if present) destroy the data */
 538         if (datastore->info->destroy != NULL && datastore->data != NULL) {
 539                 datastore->info->destroy(datastore->data);
 540                 datastore->data = NULL;
 541         }
 542
 543         ast_free((void *) datastore->uid);
 544         datastore->uid = NULL;
 545 }
 546
 547 struct ast_datastore *ast_sip_session_alloc_datastore(const struct ast_datastore_info *info, const char *uid)
 548 {
 549         RAII_VAR(struct ast_datastore *, datastore, NULL, ao2_cleanup);
 550         const char *uid_ptr = uid;
 551
 552         if (!info) {
 553                 return NULL;
 554         }
 555
 556         datastore = ao2_alloc(sizeof(*datastore), session_datastore_destroy);
 557         if (!datastore) {
 558                 return NULL;
 559         }
 560
 561         datastore->info = info;
 562         if (ast_strlen_zero(uid)) {
 563                 /* They didn't provide an ID so we'll provide one ourself */
 564                 struct ast_uuid *uuid = ast_uuid_generate();
 565                 char uuid_buf[AST_UUID_STR_LEN];
 566                 if (!uuid) {
 567                         return NULL;
 568                 }
 569                 uid_ptr = ast_uuid_to_str(uuid, uuid_buf, sizeof(uuid_buf));
 570                 ast_free(uuid);
 571         }
 572
 573         datastore->uid = ast_strdup(uid_ptr);
 574         if (!datastore->uid) {
 575                 return NULL;
 576         }
 577
 578         ao2_ref(datastore, +1);
 579         return datastore;
 580 }
 581
 582 int ast_sip_session_add_datastore(struct ast_sip_session *session, struct ast_datastore *datastore)
 583 {
 584         ast_assert(datastore != NULL);
 585         ast_assert(datastore->info != NULL);
 586         ast_assert(ast_strlen_zero(datastore->uid) == 0);
 587
 588         if (!ao2_link(session->datastores, datastore)) {
 589                 return -1;
 590         }
 591         return 0;
 592 }
 593
 594 struct ast_datastore *ast_sip_session_get_datastore(struct ast_sip_session *session, const char *name)
 595 {
 596         return ao2_find(session->datastores, name, OBJ_KEY);
 597 }
 598
 599 void ast_sip_session_remove_datastore(struct ast_sip_session *session, const char *name)
 600 {
 601         ao2_callback(session->datastores, OBJ_KEY | OBJ_UNLINK | OBJ_NODATA, NULL, (void *) name);
 602 }
 603
 604 /*!
 605  * \brief Structure used for sending delayed requests
 606  *
 607  * Requests are typically delayed because the current transaction
 608  * state of an INVITE. Once the pending INVITE transaction terminates,
 609  * the delayed request will be sent
 610  */
 611 struct ast_sip_session_delayed_request {
 612         /*! Method of the request */
 613         char method[15];
 614         /*! Callback to call when the delayed request is created. */
 615         ast_sip_session_request_creation_cb on_request_creation;
 616         /*! Callback to call when the delayed request SDP is created */
 617         ast_sip_session_sdp_creation_cb on_sdp_creation;
 618         /*! Callback to call when the delayed request receives a response */
 619         ast_sip_session_response_cb on_response;
 620         /*! Request to send */
 621         pjsip_tx_data *tdata;
 622         AST_LIST_ENTRY(ast_sip_session_delayed_request) next;
 623 };
 624
 625 static struct ast_sip_session_delayed_request *delayed_request_alloc(const char *method,
 626                 ast_sip_session_request_creation_cb on_request_creation,
 627                 ast_sip_session_sdp_creation_cb on_sdp_creation,
 628                 ast_sip_session_response_cb on_response,
 629                 pjsip_tx_data *tdata)
 630 {
 631         struct ast_sip_session_delayed_request *delay = ast_calloc(1, sizeof(*delay));
 632         if (!delay) {
 633                 return NULL;
 634         }
 635         ast_copy_string(delay->method, method, sizeof(delay->method));
 636         delay->on_request_creation = on_request_creation;
 637         delay->on_sdp_creation = on_sdp_creation;
 638         delay->on_response = on_response;
 639         delay->tdata = tdata;
 640         return delay;
 641 }
 642
 643 static int send_delayed_request(struct ast_sip_session *session, struct ast_sip_session_delayed_request *delay)
 644 {
 645         ast_debug(3, "Sending delayed %s request to %s\n", delay->method, ast_sorcery_object_get_id(session->endpoint));
 646
 647         if (delay->tdata) {
 648                 ast_sip_session_send_request_with_cb(session, delay->tdata, delay->on_response);
 649                 return 0;
 650         }
 651
 652         if (!strcmp(delay->method, "INVITE")) {
 653                 ast_sip_session_refresh(session, delay->on_request_creation,
 654                                 delay->on_sdp_creation, delay->on_response, AST_SIP_SESSION_REFRESH_METHOD_INVITE, 1);
 655         } else if (!strcmp(delay->method, "UPDATE")) {
 656                 ast_sip_session_refresh(session, delay->on_request_creation,
 657                                 delay->on_sdp_creation, delay->on_response, AST_SIP_SESSION_REFRESH_METHOD_UPDATE, 1);
 658         } else {
 659                 ast_log(LOG_WARNING, "Unexpected delayed %s request with no existing request structure\n", delay->method);
 660                 return -1;
 661         }
 662         return 0;
 663 }
 664
 665 static int queued_delayed_request_send(void *data)
 666 {
 667         RAII_VAR(struct ast_sip_session *, session, data, ao2_cleanup);
 668         RAII_VAR(struct ast_sip_session_delayed_request *, delay, NULL, ast_free_ptr);
 669
 670         delay = AST_LIST_REMOVE_HEAD(&session->delayed_requests, next);
 671         if (!delay) {
 672                 return 0;
 673         }
 674
 675         return send_delayed_request(session, delay);
 676 }
 677
 678 static void queue_delayed_request(struct ast_sip_session *session)
 679 {
 680         if (AST_LIST_EMPTY(&session->delayed_requests)) {
 681                 /* No delayed request to send, so just return */
 682                 return;
 683         }
 684
 685         ast_debug(3, "Queuing delayed request to run for %s\n",
 686                         ast_sorcery_object_get_id(session->endpoint));
 687
 688         ao2_ref(session, +1);
 689         ast_sip_push_task(session->serializer, queued_delayed_request_send, session);
 690 }
 691
 692 static int delay_request(struct ast_sip_session *session, ast_sip_session_request_creation_cb on_request,
 693                 ast_sip_session_sdp_creation_cb on_sdp_creation, ast_sip_session_response_cb on_response,
 694                 const char *method, pjsip_tx_data *tdata)
 695 {
 696         struct ast_sip_session_delayed_request *delay = delayed_request_alloc(method,
 697                         on_request, on_sdp_creation, on_response, tdata);
 698
 699         if (!delay) {
 700                 return -1;
 701         }
 702
 703         AST_LIST_INSERT_TAIL(&session->delayed_requests, delay, next);
 704         return 0;
 705 }
 706
 707 static pjmedia_sdp_session *generate_session_refresh_sdp(struct ast_sip_session *session)
 708 {
 709         pjsip_inv_session *inv_session = session->inv_session;
 710         const pjmedia_sdp_session *previous_sdp;
 711
 712         if (pjmedia_sdp_neg_was_answer_remote(inv_session->neg)) {
 713                 pjmedia_sdp_neg_get_active_remote(inv_session->neg, &previous_sdp);
 714         } else {
 715                 pjmedia_sdp_neg_get_active_local(inv_session->neg, &previous_sdp);
 716         }
 717         return create_local_sdp(inv_session, session, previous_sdp);
 718 }
 719
 720 int ast_sip_session_refresh(struct ast_sip_session *session,
 721                 ast_sip_session_request_creation_cb on_request_creation,
 722                 ast_sip_session_sdp_creation_cb on_sdp_creation,
 723                 ast_sip_session_response_cb on_response,
 724                 enum ast_sip_session_refresh_method method, int generate_new_sdp)
 725 {
 726         pjsip_inv_session *inv_session = session->inv_session;
 727         pjmedia_sdp_session *new_sdp = NULL;
 728         pjsip_tx_data *tdata;
 729
 730         if (inv_session->state == PJSIP_INV_STATE_DISCONNECTED) {
 731                 /* Don't try to do anything with a hung-up call */
 732                 ast_debug(3, "Not sending reinvite to %s because of disconnected state...\n",
 733                                 ast_sorcery_object_get_id(session->endpoint));
 734                 return 0;
 735         }
 736
 737         if (method == AST_SIP_SESSION_REFRESH_METHOD_INVITE) {
 738                 if (inv_session->invite_tsx) {
 739                         /* We can't send a reinvite yet, so delay it */
 740                         ast_debug(3, "Delaying sending reinvite to %s because of outstanding transaction...\n",
 741                                         ast_sorcery_object_get_id(session->endpoint));
 742                         return delay_request(session, on_request_creation, on_sdp_creation, on_response, "INVITE", NULL);
 743                 } else if (inv_session->state != PJSIP_INV_STATE_CONFIRMED) {
 744                         /* Initial INVITE transaction failed to progress us to a confirmed state
 745                          * which means re-invites are not possible
 746                          */
 747                         ast_debug(3, "Not sending reinvite to %s because not in confirmed state...\n",
 748                                         ast_sorcery_object_get_id(session->endpoint));
 749                         return 0;
 750                 }
 751         }
 752
 753         if (generate_new_sdp) {
 754                 new_sdp = generate_session_refresh_sdp(session);
 755                 if (!new_sdp) {
 756                         ast_log(LOG_ERROR, "Failed to generate session refresh SDP. Not sending session refresh\n");
 757                         return -1;
 758                 }
 759                 if (on_sdp_creation) {
 760                         if (on_sdp_creation(session, new_sdp)) {
 761                                 return -1;
 762                         }
 763                 }
 764         }
 765
 766         if (method == AST_SIP_SESSION_REFRESH_METHOD_INVITE) {
 767                 if (pjsip_inv_reinvite(inv_session, NULL, new_sdp, &tdata)) {
 768                         ast_log(LOG_WARNING, "Failed to create reinvite properly.\n");
 769                         return -1;
 770                 }
 771         } else if (pjsip_inv_update(inv_session, NULL, new_sdp, &tdata)) {
 772                 ast_log(LOG_WARNING, "Failed to create UPDATE properly.\n");
 773                 return -1;
 774         }
 775         if (on_request_creation) {
 776                 if (on_request_creation(session, tdata)) {
 777                         return -1;
 778                 }
 779         }
 780         ast_debug(3, "Sending session refresh SDP via %s to %s\n",
 781                 method == AST_SIP_SESSION_REFRESH_METHOD_INVITE ? "re-INVITE" : "UPDATE",
 782                 ast_sorcery_object_get_id(session->endpoint));
 783         ast_sip_session_send_request_with_cb(session, tdata, on_response);
 784         return 0;
 785 }
 786
 787 void ast_sip_session_send_response(struct ast_sip_session *session, pjsip_tx_data *tdata)
 788 {
 789         handle_outgoing_response(session, tdata);
 790         pjsip_inv_send_msg(session->inv_session, tdata);
 791         return;
 792 }
 793
 794 static pj_bool_t session_on_rx_request(pjsip_rx_data *rdata);
 795
 796 static pjsip_module session_module = {
 797         .name = {"Session Module", 14},
 798         .priority = PJSIP_MOD_PRIORITY_APPLICATION,
 799         .on_rx_request = session_on_rx_request,
 800 };
 801
 802 /*! \brief Determine whether the SDP provided requires deferral of negotiating or not
 803  *
 804  * \retval 1 re-invite should be deferred and resumed later
 805  * \retval 0 re-invite should not be deferred
 806  */
 807 static int sdp_requires_deferral(struct ast_sip_session *session, const pjmedia_sdp_session *sdp)
 808 {
 809         int i;
 810
 811         if (validate_incoming_sdp(sdp)) {
 812                 return 0;
 813         }
 814
 815         for (i = 0; i < sdp->media_count; ++i) {
 816                 /* See if there are registered handlers for this media stream type */
 817                 char media[20];
 818                 struct ast_sip_session_sdp_handler *handler;
 819                 RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
 820                 RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
 821                 enum ast_sip_session_sdp_stream_defer res;
 822
 823                 /* We need a null-terminated version of the media string */
 824                 ast_copy_pj_str(media, &sdp->media[i]->desc.media, sizeof(media));
 825
 826                 session_media = ao2_find(session->media, media, OBJ_KEY);
 827                 if (!session_media) {
 828                         /* if the session_media doesn't exist, there weren't
 829                          * any handlers at the time of its creation */
 830                         continue;
 831                 }
 832
 833                 if (session_media->handler) {
 834                         handler = session_media->handler;
 835                         if (handler->defer_incoming_sdp_stream) {
 836                                 res = handler->defer_incoming_sdp_stream(session, session_media, sdp,
 837                                         sdp->media[i]);
 838                                 switch (res) {
 839                                 case AST_SIP_SESSION_SDP_DEFER_NOT_HANDLED:
 840                                         break;
 841                                 case AST_SIP_SESSION_SDP_DEFER_ERROR:
 842                                         return 0;
 843                                 case AST_SIP_SESSION_SDP_DEFER_NOT_NEEDED:
 844                                         break;
 845                                 case AST_SIP_SESSION_SDP_DEFER_NEEDED:
 846                                         return 1;
 847                                 }
 848                         }
 849                         /* Handled by this handler. Move to the next stream */
 850                         continue;
 851                 }
 852
 853                 handler_list = ao2_find(sdp_handlers, media, OBJ_KEY);
 854                 if (!handler_list) {
 855                         ast_debug(1, "No registered SDP handlers for media type '%s'\n", media);
 856                         continue;
 857                 }
 858                 AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
 859                         if (!handler->defer_incoming_sdp_stream) {
 860                                 continue;
 861                         }
 862                         res = handler->defer_incoming_sdp_stream(session, session_media, sdp,
 863                                 sdp->media[i]);
 864                         switch (res) {
 865                         case AST_SIP_SESSION_SDP_DEFER_NOT_HANDLED:
 866                                 continue;
 867                         case AST_SIP_SESSION_SDP_DEFER_ERROR:
 868                                 session_media->handler = handler;
 869                                 return 0;
 870                         case AST_SIP_SESSION_SDP_DEFER_NOT_NEEDED:
 871                                 /* Handled by this handler. */
 872                                 session_media->handler = handler;
 873                                 break;
 874                         case AST_SIP_SESSION_SDP_DEFER_NEEDED:
 875                                 /* Handled by this handler. */
 876                                 session_media->handler = handler;
 877                                 return 1;
 878                         }
 879                         /* Move to the next stream */
 880                         break;
 881                 }
 882         }
 883         return 0;
 884 }
 885
 886 static pj_bool_t session_reinvite_on_rx_request(pjsip_rx_data *rdata)
 887 {
 888         pjsip_dialog *dlg;
 889         RAII_VAR(struct ast_sip_session *, session, NULL, ao2_cleanup);
 890         pjsip_rdata_sdp_info *sdp_info;
 891
 892         if (rdata->msg_info.msg->line.req.method.id != PJSIP_INVITE_METHOD ||
 893                 !(dlg = pjsip_ua_find_dialog(&rdata->msg_info.cid->id, &rdata->msg_info.to->tag, &rdata->msg_info.from->tag, PJ_FALSE)) ||
 894                 !(session = ast_sip_dialog_get_session(dlg))) {
 895                 return PJ_FALSE;
 896         }
 897
 898         if (session->deferred_reinvite) {
 899                 pj_str_t key, deferred_key;
 900                 pjsip_tx_data *tdata;
 901
 902                 /* We use memory from the new request on purpose so the deferred reinvite pool does not grow uncontrollably */
 903                 pjsip_tsx_create_key(rdata->tp_info.pool, &key, PJSIP_ROLE_UAS, &rdata->msg_info.cseq->method, rdata);
 904                 pjsip_tsx_create_key(rdata->tp_info.pool, &deferred_key, PJSIP_ROLE_UAS, &session->deferred_reinvite->msg_info.cseq->method,
 905                         session->deferred_reinvite);
 906
 907                 /* If this is a retransmission ignore it */
 908                 if (!pj_strcmp(&key, &deferred_key)) {
 909                         return PJ_TRUE;
 910                 }
 911
 912                 /* Otherwise this is a new re-invite, so reject it */
 913                 if (pjsip_dlg_create_response(dlg, rdata, 491, NULL, &tdata) == PJ_SUCCESS) {
 914                         pjsip_endpt_send_response2(ast_sip_get_pjsip_endpoint(), rdata, tdata, NULL, NULL);
 915                 }
 916
 917                 return PJ_TRUE;
 918         }
 919
 920         if (!(sdp_info = pjsip_rdata_get_sdp_info(rdata)) ||
 921                 (sdp_info->sdp_err != PJ_SUCCESS)) {
 922                 return PJ_FALSE;
 923         }
 924
 925         if (!sdp_info->sdp) {
 926                 ast_queue_unhold(session->channel);
 927                 return PJ_FALSE;
 928         }
 929
 930         if (!sdp_requires_deferral(session, sdp_info->sdp)) {
 931                 return PJ_FALSE;
 932         }
 933
 934         pjsip_rx_data_clone(rdata, 0, &session->deferred_reinvite);
 935
 936         return PJ_TRUE;
 937 }
 938
 939 void ast_sip_session_resume_reinvite(struct ast_sip_session *session)
 940 {
 941         if (!session->deferred_reinvite) {
 942                 return;
 943         }
 944
 945         pjsip_endpt_process_rx_data(ast_sip_get_pjsip_endpoint(), session->deferred_reinvite, NULL, NULL);
 946         pjsip_rx_data_free_cloned(session->deferred_reinvite);
 947         session->deferred_reinvite = NULL;
 948 }
 949
 950 static pjsip_module session_reinvite_module = {
 951         .name = { "Session Re-Invite Module", 24 },
 952         .priority = PJSIP_MOD_PRIORITY_UA_PROXY_LAYER - 1,
 953         .on_rx_request = session_reinvite_on_rx_request,
 954 };
 955
 956 void ast_sip_session_send_request_with_cb(struct ast_sip_session *session, pjsip_tx_data *tdata,
 957                 ast_sip_session_response_cb on_response)
 958 {
 959         pjsip_inv_session *inv_session = session->inv_session;
 960
 961         if (inv_session->state == PJSIP_INV_STATE_DISCONNECTED) {
 962                 /* Don't try to do anything with a hung-up call */
 963                 return;
 964         }
 965
 966         ast_sip_mod_data_set(tdata->pool, tdata->mod_data, session_module.id,
 967                              MOD_DATA_ON_RESPONSE, on_response);
 968
 969         if (!ast_strlen_zero(session->endpoint->fromuser) ||
 970                 !ast_strlen_zero(session->endpoint->fromdomain)) {
 971                 pjsip_fromto_hdr *from = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_FROM, tdata->msg->hdr.next);
 972                 pjsip_sip_uri *uri = pjsip_uri_get_uri(from->uri);
 973
 974                 if (!ast_strlen_zero(session->endpoint->fromuser)) {
 975                         pj_strdup2(tdata->pool, &uri->user, session->endpoint->fromuser);
 976                 }
 977                 if (!ast_strlen_zero(session->endpoint->fromdomain)) {
 978                         pj_strdup2(tdata->pool, &uri->host, session->endpoint->fromdomain);
 979                 }
 980         }
 981
 982         handle_outgoing_request(session, tdata);
 983         pjsip_inv_send_msg(session->inv_session, tdata);
 984         return;
 985 }
 986
 987 void ast_sip_session_send_request(struct ast_sip_session *session, pjsip_tx_data *tdata)
 988 {
 989         ast_sip_session_send_request_with_cb(session, tdata, NULL);
 990 }
 991
 992 int ast_sip_session_create_invite(struct ast_sip_session *session, pjsip_tx_data **tdata)
 993 {
 994         pjmedia_sdp_session *offer;
 995
 996         if (!(offer = create_local_sdp(session->inv_session, session, NULL))) {
 997                 pjsip_inv_terminate(session->inv_session, 500, PJ_FALSE);
 998                 return -1;
 999         }
1000
1001         pjsip_inv_set_local_sdp(session->inv_session, offer);
1002         pjmedia_sdp_neg_set_prefer_remote_codec_order(session->inv_session->neg, PJ_FALSE);
1003 #ifdef PJMEDIA_SDP_NEG_ANSWER_MULTIPLE_CODECS
1004         pjmedia_sdp_neg_set_answer_multiple_codecs(session->inv_session->neg, PJ_TRUE);
1005 #endif
1006         if (pjsip_inv_invite(session->inv_session, tdata) != PJ_SUCCESS) {
1007                 return -1;
1008         }
1009         return 0;
1010 }
1011
1012 static int datastore_hash(const void *obj, int flags)
1013 {
1014         const struct ast_datastore *datastore = obj;
1015         const char *uid = flags & OBJ_KEY ? obj : datastore->uid;
1016
1017         ast_assert(uid != NULL);
1018
1019         return ast_str_hash(uid);
1020 }
1021
1022 static int datastore_cmp(void *obj, void *arg, int flags)
1023 {
1024         const struct ast_datastore *datastore1 = obj;
1025         const struct ast_datastore *datastore2 = arg;
1026         const char *uid2 = flags & OBJ_KEY ? arg : datastore2->uid;
1027
1028         ast_assert(datastore1->uid != NULL);
1029         ast_assert(uid2 != NULL);
1030
1031         return strcmp(datastore1->uid, uid2) ? 0 : CMP_MATCH | CMP_STOP;
1032 }
1033
1034 static void session_media_dtor(void *obj)
1035 {
1036         struct ast_sip_session_media *session_media = obj;
1037         if (session_media->handler) {
1038                 session_media->handler->stream_destroy(session_media);
1039         }
1040         if (session_media->srtp) {
1041                 ast_sdp_srtp_destroy(session_media->srtp);
1042         }
1043 }
1044
1045 static void session_destructor(void *obj)
1046 {
1047         struct ast_sip_session *session = obj;
1048         struct ast_sip_session_supplement *supplement;
1049         struct ast_sip_session_delayed_request *delay;
1050
1051         ast_debug(3, "Destroying SIP session with endpoint %s\n",
1052                         ast_sorcery_object_get_id(session->endpoint));
1053
1054         while ((supplement = AST_LIST_REMOVE_HEAD(&session->supplements, next))) {
1055                 if (supplement->session_destroy) {
1056                         supplement->session_destroy(session);
1057                 }
1058                 ast_free(supplement);
1059         }
1060
1061         ast_taskprocessor_unreference(session->serializer);
1062         ao2_cleanup(session->datastores);
1063         ao2_cleanup(session->media);
1064
1065         AST_LIST_HEAD_DESTROY(&session->supplements);
1066         while ((delay = AST_LIST_REMOVE_HEAD(&session->delayed_requests, next))) {
1067                 ast_free(delay);
1068         }
1069         ast_party_id_free(&session->id);
1070         ao2_cleanup(session->endpoint);
1071         ao2_cleanup(session->contact);
1072         ao2_cleanup(session->req_caps);
1073         ao2_cleanup(session->direct_media_cap);
1074
1075         if (session->dsp) {
1076                 ast_dsp_free(session->dsp);
1077         }
1078
1079         if (session->inv_session) {
1080                 pjsip_dlg_dec_session(session->inv_session->dlg, &session_module);
1081         }
1082 }
1083
1084 static int add_supplements(struct ast_sip_session *session)
1085 {
1086         struct ast_sip_session_supplement *iter;
1087         SCOPED_LOCK(lock, &session_supplements, AST_RWLIST_RDLOCK, AST_RWLIST_UNLOCK);
1088
1089         AST_RWLIST_TRAVERSE(&session_supplements, iter, next) {
1090                 struct ast_sip_session_supplement *copy = supplement_dup(iter);
1091                 if (!copy) {
1092                         return -1;
1093                 }
1094                 AST_LIST_INSERT_TAIL(&session->supplements, copy, next);
1095         }
1096         return 0;
1097 }
1098
1099 static int add_session_media(void *obj, void *arg, int flags)
1100 {
1101         struct sdp_handler_list *handler_list = obj;
1102         struct ast_sip_session * session = arg;
1103         RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
1104         session_media = ao2_alloc(sizeof(*session_media) + strlen(handler_list->stream_type), session_media_dtor);
1105         if (!session_media) {
1106                 return CMP_STOP;
1107         }
1108         /* Safe use of strcpy */
1109         strcpy(session_media->stream_type, handler_list->stream_type);
1110         ao2_link(session->media, session_media);
1111         return 0;
1112 }
1113
1114 /*! \brief Destructor for SIP channel */
1115 static void sip_channel_destroy(void *obj)
1116 {
1117         struct ast_sip_channel_pvt *channel = obj;
1118
1119         ao2_cleanup(channel->pvt);
1120         ao2_cleanup(channel->session);
1121 }
1122
1123 struct ast_sip_channel_pvt *ast_sip_channel_pvt_alloc(void *pvt, struct ast_sip_session *session)
1124 {
1125         struct ast_sip_channel_pvt *channel = ao2_alloc(sizeof(*channel), sip_channel_destroy);
1126
1127         if (!channel) {
1128                 return NULL;
1129         }
1130
1131         ao2_ref(pvt, +1);
1132         channel->pvt = pvt;
1133         ao2_ref(session, +1);
1134         channel->session = session;
1135
1136         return channel;
1137 }
1138
1139 struct ast_sip_session *ast_sip_session_alloc(struct ast_sip_endpoint *endpoint,
1140         struct ast_sip_contact *contact, pjsip_inv_session *inv_session)
1141 {
1142         RAII_VAR(struct ast_sip_session *, session, ao2_alloc(sizeof(*session), session_destructor), ao2_cleanup);
1143         struct ast_sip_session_supplement *iter;
1144         int dsp_features = 0;
1145         if (!session) {
1146                 return NULL;
1147         }
1148         AST_LIST_HEAD_INIT(&session->supplements);
1149         session->datastores = ao2_container_alloc(DATASTORE_BUCKETS, datastore_hash, datastore_cmp);
1150         if (!session->datastores) {
1151                 return NULL;
1152         }
1153
1154         session->media = ao2_container_alloc(MEDIA_BUCKETS, session_media_hash, session_media_cmp);
1155         if (!session->media) {
1156                 return NULL;
1157         }
1158         /* fill session->media with available types */
1159         ao2_callback(sdp_handlers, OBJ_NODATA, add_session_media, session);
1160
1161         session->serializer = ast_sip_create_serializer();
1162         if (!session->serializer) {
1163                 return NULL;
1164         }
1165         ast_sip_dialog_set_serializer(inv_session->dlg, session->serializer);
1166         ast_sip_dialog_set_endpoint(inv_session->dlg, endpoint);
1167         pjsip_dlg_inc_session(inv_session->dlg, &session_module);
1168         inv_session->mod_data[session_module.id] = ao2_bump(session);
1169         session->endpoint = ao2_bump(endpoint);
1170         session->contact = ao2_bump(contact);
1171         session->inv_session = inv_session;
1172         session->req_caps = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
1173
1174         if (endpoint->dtmf == AST_SIP_DTMF_INBAND) {
1175                 dsp_features |= DSP_FEATURE_DIGIT_DETECT;
1176         }
1177
1178         if (endpoint->faxdetect) {
1179                 dsp_features |= DSP_FEATURE_FAX_DETECT;
1180         }
1181
1182         if (dsp_features) {
1183                 if (!(session->dsp = ast_dsp_new())) {
1184                         ao2_ref(session, -1);
1185                         return NULL;
1186                 }
1187
1188                 ast_dsp_set_features(session->dsp, dsp_features);
1189         }
1190
1191         if (add_supplements(session)) {
1192                 ao2_ref(session, -1);
1193                 return NULL;
1194         }
1195         AST_LIST_TRAVERSE(&session->supplements, iter, next) {
1196                 if (iter->session_begin) {
1197                         iter->session_begin(session);
1198                 }
1199         }
1200         session->direct_media_cap = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
1201         AST_LIST_HEAD_INIT_NOLOCK(&session->delayed_requests);
1202         ast_party_id_init(&session->id);
1203         ao2_ref(session, +1);
1204         return session;
1205 }
1206
1207 static int session_outbound_auth(pjsip_dialog *dlg, pjsip_tx_data *tdata, void *user_data)
1208 {
1209         pjsip_inv_session *inv = pjsip_dlg_get_inv_session(dlg);
1210         struct ast_sip_session *session = inv->mod_data[session_module.id];
1211
1212         if (inv->state < PJSIP_INV_STATE_CONFIRMED && tdata->msg->line.req.method.id == PJSIP_INVITE_METHOD) {
1213                 pjsip_inv_uac_restart(inv, PJ_FALSE);
1214         }
1215         ast_sip_session_send_request(session, tdata);
1216         return 0;
1217 }
1218
1219 struct ast_sip_session *ast_sip_session_create_outgoing(struct ast_sip_endpoint *endpoint,
1220         struct ast_sip_contact *contact, const char *location, const char *request_user,
1221         struct ast_format_cap *req_caps)
1222 {
1223         const char *uri = NULL;
1224         RAII_VAR(struct ast_sip_contact *, found_contact, NULL, ao2_cleanup);
1225         pjsip_timer_setting timer;
1226         pjsip_dialog *dlg;
1227         struct pjsip_inv_session *inv_session;
1228         RAII_VAR(struct ast_sip_session *, session, NULL, ao2_cleanup);
1229
1230         /* If no location has been provided use the AOR list from the endpoint itself */
1231         if (location || !contact) {
1232                 location = S_OR(location, endpoint->aors);
1233
1234                 found_contact = ast_sip_location_retrieve_contact_from_aor_list(location);
1235                 if (!found_contact || ast_strlen_zero(found_contact->uri)) {
1236                         uri = location;
1237                 } else {
1238                         uri = found_contact->uri;
1239                 }
1240         } else {
1241                 uri = contact->uri;
1242         }
1243
1244         /* If we still have no URI to dial fail to create the session */
1245         if (ast_strlen_zero(uri)) {
1246                 return NULL;
1247         }
1248
1249         if (!(dlg = ast_sip_create_dialog_uac(endpoint, uri, request_user))) {
1250                 return NULL;
1251         }
1252
1253         if (ast_sip_dialog_setup_outbound_authentication(dlg, endpoint, session_outbound_auth, NULL)) {
1254                 pjsip_dlg_terminate(dlg);
1255                 return NULL;
1256         }
1257
1258         if (pjsip_inv_create_uac(dlg, NULL, endpoint->extensions.flags, &inv_session) != PJ_SUCCESS) {
1259                 pjsip_dlg_terminate(dlg);
1260                 return NULL;
1261         }
1262 #if defined(HAVE_PJSIP_REPLACE_MEDIA_STREAM) || defined(PJMEDIA_SDP_NEG_ALLOW_MEDIA_CHANGE)
1263         inv_session->sdp_neg_flags = PJMEDIA_SDP_NEG_ALLOW_MEDIA_CHANGE;
1264 #endif
1265
1266         pjsip_timer_setting_default(&timer);
1267         timer.min_se = endpoint->extensions.timer.min_se;
1268         timer.sess_expires = endpoint->extensions.timer.sess_expires;
1269         pjsip_timer_init_session(inv_session, &timer);
1270
1271         if (!(session = ast_sip_session_alloc(endpoint, found_contact ? found_contact : contact, inv_session))) {
1272                 pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1273                 return NULL;
1274         }
1275
1276         if (ast_format_cap_count(req_caps)) {
1277                 /* get joint caps between req_caps and endpoint caps */
1278                 struct ast_format_cap *joint_caps = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
1279                 ast_format_cap_get_compatible(req_caps, session->endpoint->media.codecs, joint_caps);
1280
1281                 /* if joint caps */
1282                 if (ast_format_cap_count(joint_caps)) {
1283                         /* copy endpoint caps into session->req_caps */
1284                         ast_format_cap_append_from_cap(session->req_caps, session->endpoint->media.codecs, AST_MEDIA_TYPE_UNKNOWN);
1285                         /* replace instances of joint caps equivalents in session->req_caps */
1286                         ast_format_cap_replace_from_cap(session->req_caps, joint_caps, AST_MEDIA_TYPE_UNKNOWN);
1287                 }
1288                 ao2_cleanup(joint_caps);
1289         }
1290
1291         if ((pjsip_dlg_add_usage(dlg, &session_module, NULL) != PJ_SUCCESS)) {
1292                 pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1293                 /* Since we are not notifying ourselves that the INVITE session is being terminated
1294                  * we need to manually drop its reference to session
1295                  */
1296                 ao2_ref(session, -1);
1297                 return NULL;
1298         }
1299
1300         ao2_ref(session, +1);
1301         return session;
1302 }
1303
1304 static int session_termination_task(void *data)
1305 {
1306         RAII_VAR(struct ast_sip_session *, session, data, ao2_cleanup);
1307         pjsip_tx_data *packet = NULL;
1308
1309         if (!session->inv_session) {
1310                 return 0;
1311         }
1312
1313         if (pjsip_inv_end_session(session->inv_session, 603, NULL, &packet) == PJ_SUCCESS) {
1314                 ast_sip_session_send_request(session, packet);
1315         }
1316
1317         return 0;
1318 }
1319
1320 static void session_termination_cb(pj_timer_heap_t *timer_heap, struct pj_timer_entry *entry)
1321 {
1322         struct ast_sip_session *session = entry->user_data;
1323
1324         if (ast_sip_push_task(session->serializer, session_termination_task, session)) {
1325                 ao2_cleanup(session);
1326         }
1327 }
1328
1329 void ast_sip_session_defer_termination(struct ast_sip_session *session)
1330 {
1331         pj_time_val delay = { .sec = 60, };
1332
1333         session->defer_terminate = 1;
1334
1335         session->scheduled_termination.id = 0;
1336         ao2_ref(session, +1);
1337         session->scheduled_termination.user_data = session;
1338         session->scheduled_termination.cb = session_termination_cb;
1339
1340         if (pjsip_endpt_schedule_timer(ast_sip_get_pjsip_endpoint(), &session->scheduled_termination, &delay) != PJ_SUCCESS) {
1341                 ao2_ref(session, -1);
1342         }
1343 }
1344
1345 struct ast_sip_session *ast_sip_dialog_get_session(pjsip_dialog *dlg)
1346 {
1347         pjsip_inv_session *inv_session = pjsip_dlg_get_inv_session(dlg);
1348         struct ast_sip_session *session;
1349
1350         if (!inv_session ||
1351                 !(session = inv_session->mod_data[session_module.id])) {
1352                 return NULL;
1353         }
1354
1355         ao2_ref(session, +1);
1356
1357         return session;
1358 }
1359
1360 enum sip_get_destination_result {
1361         /*! The extension was successfully found */
1362         SIP_GET_DEST_EXTEN_FOUND,
1363         /*! The extension specified in the RURI was not found */
1364         SIP_GET_DEST_EXTEN_NOT_FOUND,
1365         /*! The extension specified in the RURI was a partial match */
1366         SIP_GET_DEST_EXTEN_PARTIAL,
1367         /*! The RURI is of an unsupported scheme */
1368         SIP_GET_DEST_UNSUPPORTED_URI,
1369 };
1370
1371 /*!
1372  * \brief Determine where in the dialplan a call should go
1373  *
1374  * This uses the username in the request URI to try to match
1375  * an extension in the endpoint's configured context in order
1376  * to route the call.
1377  *
1378  * \param session The inbound SIP session
1379  * \param rdata The SIP INVITE
1380  */
1381 static enum sip_get_destination_result get_destination(struct ast_sip_session *session, pjsip_rx_data *rdata)
1382 {
1383         pjsip_uri *ruri = rdata->msg_info.msg->line.req.uri;
1384         pjsip_sip_uri *sip_ruri;
1385         struct ast_features_pickup_config *pickup_cfg;
1386         const char *pickupexten;
1387
1388         if (!PJSIP_URI_SCHEME_IS_SIP(ruri) && !PJSIP_URI_SCHEME_IS_SIPS(ruri)) {
1389                 return SIP_GET_DEST_UNSUPPORTED_URI;
1390         }
1391
1392         sip_ruri = pjsip_uri_get_uri(ruri);
1393         ast_copy_pj_str(session->exten, &sip_ruri->user, sizeof(session->exten));
1394
1395         pickup_cfg = ast_get_chan_features_pickup_config(session->channel);
1396         if (!pickup_cfg) {
1397                 ast_log(LOG_ERROR, "Unable to retrieve pickup configuration options. Unable to detect call pickup extension\n");
1398                 pickupexten = "";
1399         } else {
1400                 pickupexten = ast_strdupa(pickup_cfg->pickupexten);
1401                 ao2_ref(pickup_cfg, -1);
1402         }
1403
1404         if (!strcmp(session->exten, pickupexten) ||
1405                 ast_exists_extension(NULL, session->endpoint->context, session->exten, 1, NULL)) {
1406                 return SIP_GET_DEST_EXTEN_FOUND;
1407         }
1408         /* XXX In reality, we'll likely have further options so that partial matches
1409          * can be indicated here, but for getting something up and running, we're going
1410          * to return a "not exists" error here.
1411          */
1412         return SIP_GET_DEST_EXTEN_NOT_FOUND;
1413 }
1414
1415 static pjsip_inv_session *pre_session_setup(pjsip_rx_data *rdata, const struct ast_sip_endpoint *endpoint)
1416 {
1417         pjsip_tx_data *tdata;
1418         pjsip_dialog *dlg;
1419         pjsip_inv_session *inv_session;
1420         unsigned int options = endpoint->extensions.flags;
1421
1422         if (pjsip_inv_verify_request(rdata, &options, NULL, NULL, ast_sip_get_pjsip_endpoint(), &tdata) != PJ_SUCCESS) {
1423                 if (tdata) {
1424                         pjsip_endpt_send_response2(ast_sip_get_pjsip_endpoint(), rdata, tdata, NULL, NULL);
1425                 } else {
1426                         pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 500, NULL, NULL, NULL);
1427                 }
1428                 return NULL;
1429         }
1430         dlg = ast_sip_create_dialog_uas(endpoint, rdata);
1431         if (!dlg) {
1432                 pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 500, NULL, NULL, NULL);
1433                 return NULL;
1434         }
1435         if (pjsip_inv_create_uas(dlg, rdata, NULL, options, &inv_session) != PJ_SUCCESS) {
1436                 pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 500, NULL, NULL, NULL);
1437                 pjsip_dlg_terminate(dlg);
1438                 return NULL;
1439         }
1440
1441 #if defined(HAVE_PJSIP_REPLACE_MEDIA_STREAM) || defined(PJMEDIA_SDP_NEG_ALLOW_MEDIA_CHANGE)
1442         inv_session->sdp_neg_flags = PJMEDIA_SDP_NEG_ALLOW_MEDIA_CHANGE;
1443 #endif
1444         if (pjsip_dlg_add_usage(dlg, &session_module, NULL) != PJ_SUCCESS) {
1445                 if (pjsip_inv_initial_answer(inv_session, rdata, 500, NULL, NULL, &tdata) != PJ_SUCCESS) {
1446                         pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1447                 }
1448                 pjsip_inv_send_msg(inv_session, tdata);
1449                 return NULL;
1450         }
1451         return inv_session;
1452 }
1453
1454 struct new_invite {
1455         /*! \brief Session created for the new INVITE */
1456         struct ast_sip_session *session;
1457
1458         /*! \brief INVITE request itself */
1459         pjsip_rx_data *rdata;
1460 };
1461
1462 static void new_invite_destroy(void *obj)
1463 {
1464         struct new_invite *invite = obj;
1465
1466         ao2_cleanup(invite->session);
1467
1468         if (invite->rdata) {
1469                 pjsip_rx_data_free_cloned(invite->rdata);
1470         }
1471 }
1472
1473 static struct new_invite *new_invite_alloc(struct ast_sip_session *session, pjsip_rx_data *rdata)
1474 {
1475         struct new_invite *invite = ao2_alloc(sizeof(*invite), new_invite_destroy);
1476
1477         if (!invite) {
1478                 return NULL;
1479         }
1480
1481         ao2_ref(session, +1);
1482         invite->session = session;
1483
1484         if (pjsip_rx_data_clone(rdata, 0, &invite->rdata) != PJ_SUCCESS) {
1485                 ao2_ref(invite, -1);
1486                 return NULL;
1487         }
1488
1489         return invite;
1490 }
1491
1492 static int new_invite(void *data)
1493 {
1494         RAII_VAR(struct new_invite *, invite, data, ao2_cleanup);
1495         pjsip_tx_data *tdata = NULL;
1496         pjsip_timer_setting timer;
1497         pjsip_rdata_sdp_info *sdp_info;
1498         pjmedia_sdp_session *local = NULL;
1499
1500         /* From this point on, any calls to pjsip_inv_terminate have the last argument as PJ_TRUE
1501          * so that we will be notified so we can destroy the session properly
1502          */
1503
1504         switch (get_destination(invite->session, invite->rdata)) {
1505         case SIP_GET_DEST_EXTEN_FOUND:
1506                 /* Things worked. Keep going */
1507                 break;
1508         case SIP_GET_DEST_UNSUPPORTED_URI:
1509                 if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 416, NULL, NULL, &tdata) == PJ_SUCCESS) {
1510                         ast_sip_session_send_response(invite->session, tdata);
1511                 } else  {
1512                         pjsip_inv_terminate(invite->session->inv_session, 416, PJ_TRUE);
1513                 }
1514                 return 0;
1515         case SIP_GET_DEST_EXTEN_NOT_FOUND:
1516         case SIP_GET_DEST_EXTEN_PARTIAL:
1517         default:
1518                 ast_log(LOG_NOTICE, "Call from '%s' (%s:%s:%d) to extension '%s' rejected because extension not found in context '%s'.\n",
1519                         ast_sorcery_object_get_id(invite->session->endpoint), invite->rdata->tp_info.transport->type_name, invite->rdata->pkt_info.src_name,
1520                         invite->rdata->pkt_info.src_port, invite->session->exten, invite->session->endpoint->context);
1521
1522                 if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 404, NULL, NULL, &tdata) == PJ_SUCCESS) {
1523                         ast_sip_session_send_response(invite->session, tdata);
1524                 } else  {
1525                         pjsip_inv_terminate(invite->session->inv_session, 404, PJ_TRUE);
1526                 }
1527                 return 0;
1528         };
1529
1530         if ((sdp_info = pjsip_rdata_get_sdp_info(invite->rdata)) && (sdp_info->sdp_err == PJ_SUCCESS) && sdp_info->sdp) {
1531                 if (handle_incoming_sdp(invite->session, sdp_info->sdp)) {
1532                         if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 488, NULL, NULL, &tdata) == PJ_SUCCESS) {
1533                                 ast_sip_session_send_response(invite->session, tdata);
1534                         } else  {
1535                                 pjsip_inv_terminate(invite->session->inv_session, 488, PJ_TRUE);
1536                         }
1537                         return 0;
1538                 }
1539                 /* We are creating a local SDP which is an answer to their offer */
1540                 local = create_local_sdp(invite->session->inv_session, invite->session, sdp_info->sdp);
1541         } else {
1542                 /* We are creating a local SDP which is an offer */
1543                 local = create_local_sdp(invite->session->inv_session, invite->session, NULL);
1544         }
1545
1546         /* If we were unable to create a local SDP terminate the session early, it won't go anywhere */
1547         if (!local) {
1548                 if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 500, NULL, NULL, &tdata) == PJ_SUCCESS) {
1549                         ast_sip_session_send_response(invite->session, tdata);
1550                 } else  {
1551                         pjsip_inv_terminate(invite->session->inv_session, 500, PJ_TRUE);
1552                 }
1553                 return 0;
1554         } else {
1555                 pjsip_inv_set_local_sdp(invite->session->inv_session, local);
1556                 pjmedia_sdp_neg_set_prefer_remote_codec_order(invite->session->inv_session->neg, PJ_FALSE);
1557 #ifdef PJMEDIA_SDP_NEG_ANSWER_MULTIPLE_CODECS
1558                 pjmedia_sdp_neg_set_answer_multiple_codecs(invite->session->inv_session->neg, PJ_TRUE);
1559 #endif
1560         }
1561
1562         pjsip_timer_setting_default(&timer);
1563         timer.min_se = invite->session->endpoint->extensions.timer.min_se;
1564         timer.sess_expires = invite->session->endpoint->extensions.timer.sess_expires;
1565         pjsip_timer_init_session(invite->session->inv_session, &timer);
1566
1567         /* At this point, we've verified what we can, so let's go ahead and send a 100 Trying out */
1568         if (pjsip_inv_initial_answer(invite->session->inv_session, invite->rdata, 100, NULL, NULL, &tdata) != PJ_SUCCESS) {
1569                 pjsip_inv_terminate(invite->session->inv_session, 500, PJ_TRUE);
1570                 return 0;
1571         }
1572         ast_sip_session_send_response(invite->session, tdata);
1573
1574         handle_incoming_request(invite->session, invite->rdata);
1575
1576         return 0;
1577 }
1578
1579 static void handle_new_invite_request(pjsip_rx_data *rdata)
1580 {
1581         RAII_VAR(struct ast_sip_endpoint *, endpoint,
1582                         ast_pjsip_rdata_get_endpoint(rdata), ao2_cleanup);
1583         pjsip_tx_data *tdata = NULL;
1584         pjsip_inv_session *inv_session = NULL;
1585         RAII_VAR(struct ast_sip_session *, session, NULL, ao2_cleanup);
1586         struct new_invite *invite;
1587
1588         ast_assert(endpoint != NULL);
1589
1590         inv_session = pre_session_setup(rdata, endpoint);
1591         if (!inv_session) {
1592                 /* pre_session_setup() returns a response on failure */
1593                 return;
1594         }
1595
1596         session = ast_sip_session_alloc(endpoint, NULL, inv_session);
1597         if (!session) {
1598                 if (pjsip_inv_initial_answer(inv_session, rdata, 500, NULL, NULL, &tdata) == PJ_SUCCESS) {
1599                         pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1600                 } else {
1601                         pjsip_inv_send_msg(inv_session, tdata);
1602                 }
1603                 return;
1604         }
1605
1606         invite = new_invite_alloc(session, rdata);
1607         if (!invite || ast_sip_push_task(session->serializer, new_invite, invite)) {
1608                 if (pjsip_inv_initial_answer(inv_session, rdata, 500, NULL, NULL, &tdata) == PJ_SUCCESS) {
1609                         pjsip_inv_terminate(inv_session, 500, PJ_FALSE);
1610                 } else {
1611                         pjsip_inv_send_msg(inv_session, tdata);
1612                 }
1613                 ao2_ref(session, -1);
1614                 ao2_cleanup(invite);
1615                 return;
1616         }
1617 }
1618
1619 static pj_bool_t does_method_match(const pj_str_t *message_method, const char *supplement_method)
1620 {
1621         pj_str_t method;
1622
1623         if (ast_strlen_zero(supplement_method)) {
1624                 return PJ_TRUE;
1625         }
1626
1627         pj_cstr(&method, supplement_method);
1628
1629         return pj_stristr(&method, message_method) ? PJ_TRUE : PJ_FALSE;
1630 }
1631
1632 static pj_bool_t has_supplement(const struct ast_sip_session *session, const pjsip_rx_data *rdata)
1633 {
1634         struct ast_sip_session_supplement *supplement;
1635         struct pjsip_method *method = &rdata->msg_info.msg->line.req.method;
1636
1637         if (!session) {
1638                 return PJ_FALSE;
1639         }
1640
1641         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1642                 if (does_method_match(&method->name, supplement->method)) {
1643                         return PJ_TRUE;
1644                 }
1645         }
1646         return PJ_FALSE;
1647 }
1648 /*!
1649  * \brief Called when a new SIP request comes into PJSIP
1650  *
1651  * This function is called under two circumstances
1652  * 1) An out-of-dialog request is received by PJSIP
1653  * 2) An in-dialog request that the inv_session layer does not
1654  *    handle is received (such as an in-dialog INFO)
1655  *
1656  * In all cases, there is very little we actually do in this function
1657  * 1) For requests we don't handle, we return PJ_FALSE
1658  * 2) For new INVITEs, throw the work into the SIP threadpool to be done
1659  *    there to free up the thread(s) handling incoming requests
1660  * 3) For in-dialog requests we handle, we defer handling them until the
1661  *    on_inv_state_change() callback instead (where we will end up putting
1662  *    them into the threadpool).
1663  */
1664 static pj_bool_t session_on_rx_request(pjsip_rx_data *rdata)
1665 {
1666         pj_status_t handled = PJ_FALSE;
1667         pjsip_dialog *dlg = pjsip_rdata_get_dlg(rdata);
1668         pjsip_inv_session *inv_session;
1669
1670         switch (rdata->msg_info.msg->line.req.method.id) {
1671         case PJSIP_INVITE_METHOD:
1672                 if (dlg) {
1673                         ast_log(LOG_WARNING, "on_rx_request called for INVITE in mid-dialog?\n");
1674                         break;
1675                 }
1676                 handled = PJ_TRUE;
1677                 handle_new_invite_request(rdata);
1678                 break;
1679         default:
1680                 /* Handle other in-dialog methods if their supplements have been registered */
1681                 handled = dlg && (inv_session = pjsip_dlg_get_inv_session(dlg)) &&
1682                         has_supplement(inv_session->mod_data[session_module.id], rdata);
1683                 break;
1684         }
1685
1686         return handled;
1687 }
1688
1689 struct reschedule_reinvite_data {
1690         struct ast_sip_session *session;
1691         struct ast_sip_session_delayed_request *delay;
1692 };
1693
1694 static struct reschedule_reinvite_data *reschedule_reinvite_data_alloc(
1695                 struct ast_sip_session *session, struct ast_sip_session_delayed_request *delay)
1696 {
1697         struct reschedule_reinvite_data *rrd = ast_malloc(sizeof(*rrd));
1698         if (!rrd) {
1699                 return NULL;
1700         }
1701         ao2_ref(session, +1);
1702         rrd->session = session;
1703         rrd->delay = delay;
1704         return rrd;
1705 }
1706
1707 static void reschedule_reinvite_data_destroy(struct reschedule_reinvite_data *rrd)
1708 {
1709         ao2_cleanup(rrd->session);
1710         ast_free(rrd->delay);
1711         ast_free(rrd);
1712 }
1713
1714 static int really_resend_reinvite(void *data)
1715 {
1716         RAII_VAR(struct reschedule_reinvite_data *, rrd, data, reschedule_reinvite_data_destroy);
1717
1718         return send_delayed_request(rrd->session, rrd->delay);
1719 }
1720
1721 static void resend_reinvite(pj_timer_heap_t *timer, pj_timer_entry *entry)
1722 {
1723         struct reschedule_reinvite_data *rrd = entry->user_data;
1724
1725         ast_sip_push_task(rrd->session->serializer, really_resend_reinvite, entry->user_data);
1726 }
1727
1728 static void reschedule_reinvite(struct ast_sip_session *session, ast_sip_session_response_cb on_response, pjsip_tx_data *tdata)
1729 {
1730         struct ast_sip_session_delayed_request *delay = delayed_request_alloc("INVITE",
1731                         NULL, NULL, on_response, tdata);
1732         pjsip_inv_session *inv = session->inv_session;
1733         struct reschedule_reinvite_data *rrd = reschedule_reinvite_data_alloc(session, delay);
1734         pj_time_val tv;
1735
1736         if (!rrd || !delay) {
1737                 return;
1738         }
1739
1740         tv.sec = 0;
1741         if (inv->role == PJSIP_ROLE_UAC) {
1742                 tv.msec = 2100 + ast_random() % 2000;
1743         } else {
1744                 tv.msec = ast_random() % 2000;
1745         }
1746
1747         pj_timer_entry_init(&session->rescheduled_reinvite, 0, rrd, resend_reinvite);
1748
1749         pjsip_endpt_schedule_timer(ast_sip_get_pjsip_endpoint(), &session->rescheduled_reinvite, &tv);
1750 }
1751
1752 static void __print_debug_details(const char *function, pjsip_inv_session *inv, pjsip_transaction *tsx, pjsip_event *e)
1753 {
1754         struct ast_sip_session *session;
1755         ast_debug(5, "Function %s called on event %s\n", function, pjsip_event_str(e->type));
1756         if (!inv) {
1757                 ast_debug(5, "Transaction %p does not belong to an inv_session?\n", tsx);
1758                 ast_debug(5, "The transaction state is %s\n", pjsip_tsx_state_str(tsx->state));
1759                 return;
1760         }
1761         session = inv->mod_data[session_module.id];
1762         if (!session) {
1763                 ast_debug(5, "inv_session %p has no ast session\n", inv);
1764         } else {
1765                 ast_debug(5, "The state change pertains to the session with %s\n",
1766                                 ast_sorcery_object_get_id(session->endpoint));
1767         }
1768         if (inv->invite_tsx) {
1769                 ast_debug(5, "The inv session still has an invite_tsx (%p)\n", inv->invite_tsx);
1770         } else {
1771                 ast_debug(5, "The inv session does NOT have an invite_tsx\n");
1772         }
1773         if (tsx) {
1774                 ast_debug(5, "The transaction involved in this state change is %p\n", tsx);
1775                 ast_debug(5, "The current transaction state is %s\n", pjsip_tsx_state_str(tsx->state));
1776                 ast_debug(5, "The transaction state change event is %s\n", pjsip_event_str(e->body.tsx_state.type));
1777         } else {
1778                 ast_debug(5, "There is no transaction involved in this state change\n");
1779         }
1780         ast_debug(5, "The current inv state is %s\n", pjsip_inv_state_name(inv->state));
1781 }
1782
1783 #define print_debug_details(inv, tsx, e) __print_debug_details(__PRETTY_FUNCTION__, (inv), (tsx), (e))
1784
1785 static void handle_incoming_request(struct ast_sip_session *session, pjsip_rx_data *rdata)
1786 {
1787         struct ast_sip_session_supplement *supplement;
1788         struct pjsip_request_line req = rdata->msg_info.msg->line.req;
1789
1790         ast_debug(3, "Method is %.*s\n", (int) pj_strlen(&req.method.name), pj_strbuf(&req.method.name));
1791         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1792                 if (supplement->incoming_request && does_method_match(&req.method.name, supplement->method)) {
1793                         if (supplement->incoming_request(session, rdata)) {
1794                                 break;
1795                         }
1796                 }
1797         }
1798 }
1799
1800 static void handle_incoming_response(struct ast_sip_session *session, pjsip_rx_data *rdata)
1801 {
1802         struct ast_sip_session_supplement *supplement;
1803         struct pjsip_status_line status = rdata->msg_info.msg->line.status;
1804
1805         ast_debug(3, "Response is %d %.*s\n", status.code, (int) pj_strlen(&status.reason),
1806                         pj_strbuf(&status.reason));
1807
1808         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1809                 if (supplement->incoming_response && does_method_match(&rdata->msg_info.cseq->method.name, supplement->method)) {
1810                         supplement->incoming_response(session, rdata);
1811                 }
1812         }
1813 }
1814
1815 static int handle_incoming(struct ast_sip_session *session, pjsip_rx_data *rdata)
1816 {
1817         ast_debug(3, "Received %s\n", rdata->msg_info.msg->type == PJSIP_REQUEST_MSG ?
1818                         "request" : "response");
1819
1820         if (rdata->msg_info.msg->type == PJSIP_REQUEST_MSG) {
1821                 handle_incoming_request(session, rdata);
1822         } else {
1823                 handle_incoming_response(session, rdata);
1824         }
1825
1826         return 0;
1827 }
1828
1829 static void handle_outgoing_request(struct ast_sip_session *session, pjsip_tx_data *tdata)
1830 {
1831         struct ast_sip_session_supplement *supplement;
1832         struct pjsip_request_line req = tdata->msg->line.req;
1833
1834         ast_debug(3, "Method is %.*s\n", (int) pj_strlen(&req.method.name), pj_strbuf(&req.method.name));
1835         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1836                 if (supplement->outgoing_request && does_method_match(&req.method.name, supplement->method)) {
1837                         supplement->outgoing_request(session, tdata);
1838                 }
1839         }
1840 }
1841
1842 static void handle_outgoing_response(struct ast_sip_session *session, pjsip_tx_data *tdata)
1843 {
1844         struct ast_sip_session_supplement *supplement;
1845         struct pjsip_status_line status = tdata->msg->line.status;
1846         pjsip_cseq_hdr *cseq = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_CSEQ, NULL);
1847         ast_debug(3, "Method is %.*s, Response is %d %.*s\n", (int) pj_strlen(&cseq->method.name),
1848                 pj_strbuf(&cseq->method.name), status.code, (int) pj_strlen(&status.reason),
1849                 pj_strbuf(&status.reason));
1850
1851         AST_LIST_TRAVERSE(&session->supplements, supplement, next) {
1852                 if (supplement->outgoing_response && does_method_match(&cseq->method.name, supplement->method)) {
1853                         supplement->outgoing_response(session, tdata);
1854                 }
1855         }
1856 }
1857
1858 static void handle_outgoing(struct ast_sip_session *session, pjsip_tx_data *tdata)
1859 {
1860         ast_debug(3, "Sending %s\n", tdata->msg->type == PJSIP_REQUEST_MSG ?
1861                         "request" : "response");
1862         if (tdata->msg->type == PJSIP_REQUEST_MSG) {
1863                 handle_outgoing_request(session, tdata);
1864         } else {
1865                 handle_outgoing_response(session, tdata);
1866         }
1867 }
1868
1869 static int session_end(struct ast_sip_session *session)
1870 {
1871         struct ast_sip_session_supplement *iter;
1872
1873         /* Stop the scheduled termination */
1874         if (pj_timer_heap_cancel(pjsip_endpt_get_timer_heap(ast_sip_get_pjsip_endpoint()), &session->scheduled_termination)) {
1875                 ao2_ref(session, -1);
1876         }
1877
1878         /* Session is dead. Let's get rid of the reference to the session */
1879         AST_LIST_TRAVERSE(&session->supplements, iter, next) {
1880                 if (iter->session_end) {
1881                         iter->session_end(session);
1882                 }
1883         }
1884
1885         session->inv_session->mod_data[session_module.id] = NULL;
1886         ast_sip_dialog_set_serializer(session->inv_session->dlg, NULL);
1887         ast_sip_dialog_set_endpoint(session->inv_session->dlg, NULL);
1888         ao2_cleanup(session);
1889         return 0;
1890 }
1891
1892 static void session_inv_on_state_changed(pjsip_inv_session *inv, pjsip_event *e)
1893 {
1894         struct ast_sip_session *session = inv->mod_data[session_module.id];
1895         pjsip_event_id_e type;
1896
1897         if (e) {
1898                 print_debug_details(inv, NULL, e);
1899                 type = e->type;
1900         } else {
1901                 type = PJSIP_EVENT_UNKNOWN;
1902         }
1903
1904         if (!session) {
1905                 return;
1906         }
1907
1908         switch(type) {
1909         case PJSIP_EVENT_TX_MSG:
1910                 handle_outgoing(session, e->body.tx_msg.tdata);
1911                 break;
1912         case PJSIP_EVENT_RX_MSG:
1913                 handle_incoming(session, e->body.rx_msg.rdata);
1914                 break;
1915         case PJSIP_EVENT_TSX_STATE:
1916                 ast_debug(3, "Source of transaction state change is %s\n", pjsip_event_str(e->body.tsx_state.type));
1917                 /* Transaction state changes are prompted by some other underlying event. */
1918                 switch(e->body.tsx_state.type) {
1919                 case PJSIP_EVENT_TX_MSG:
1920                         handle_outgoing(session, e->body.tsx_state.src.tdata);
1921                         break;
1922                 case PJSIP_EVENT_RX_MSG:
1923                         handle_incoming(session, e->body.tsx_state.src.rdata);
1924                         break;
1925                 case PJSIP_EVENT_TRANSPORT_ERROR:
1926                 case PJSIP_EVENT_TIMER:
1927                 case PJSIP_EVENT_USER:
1928                 case PJSIP_EVENT_UNKNOWN:
1929                 case PJSIP_EVENT_TSX_STATE:
1930                         /* Inception? */
1931                         break;
1932                 }
1933                 break;
1934         case PJSIP_EVENT_TRANSPORT_ERROR:
1935         case PJSIP_EVENT_TIMER:
1936         case PJSIP_EVENT_UNKNOWN:
1937         case PJSIP_EVENT_USER:
1938         default:
1939                 break;
1940         }
1941
1942         if (inv->state == PJSIP_INV_STATE_DISCONNECTED) {
1943                 session_end(session);
1944         }
1945 }
1946
1947 static void session_inv_on_new_session(pjsip_inv_session *inv, pjsip_event *e)
1948 {
1949         /* XXX STUB */
1950 }
1951
1952 static void session_inv_on_tsx_state_changed(pjsip_inv_session *inv, pjsip_transaction *tsx, pjsip_event *e)
1953 {
1954         ast_sip_session_response_cb cb;
1955         struct ast_sip_session *session = inv->mod_data[session_module.id];
1956         print_debug_details(inv, tsx, e);
1957         if (!session) {
1958                 /* Transaction likely timed out after the call was hung up. Just
1959                  * ignore such transaction changes
1960                  */
1961                 return;
1962         }
1963         switch (e->body.tsx_state.type) {
1964         case PJSIP_EVENT_TX_MSG:
1965                 /* When we create an outgoing request, we do not have access to the transaction that
1966                  * is created. Instead, We have to place transaction-specific data in the tdata. Here,
1967                  * we transfer the data into the transaction. This way, when we receive a response, we
1968                  * can dig this data out again
1969                  */
1970                 tsx->mod_data[session_module.id] = e->body.tsx_state.src.tdata->mod_data[session_module.id];
1971                 break;
1972         case PJSIP_EVENT_RX_MSG:
1973                 if (tsx->method.id == PJSIP_INVITE_METHOD) {
1974                         if (tsx->role == PJSIP_ROLE_UAC) {
1975                                 if (tsx->state == PJSIP_TSX_STATE_COMPLETED) {
1976                                         /* This means we got a non 2XX final response to our outgoing INVITE */
1977                                         if (tsx->status_code == PJSIP_SC_REQUEST_PENDING) {
1978                                                 reschedule_reinvite(session, tsx->mod_data[session_module.id], tsx->last_tx);
1979                                                 return;
1980                                         } else if (inv->state == PJSIP_INV_STATE_CONFIRMED &&
1981                                                    tsx->status_code != 488) {
1982                                                 /* Other reinvite failures (except 488) result in destroying the session. */
1983                                                 pjsip_tx_data *tdata;
1984                                                 if (pjsip_inv_end_session(inv, 500, NULL, &tdata) == PJ_SUCCESS) {
1985                                                         ast_sip_session_send_request(session, tdata);
1986                                                 }
1987                                         }
1988                                 } else if (tsx->state == PJSIP_TSX_STATE_TERMINATED) {
1989                                         if (inv->cancelling && tsx->status_code == PJSIP_SC_OK) {
1990                                                 /* This is a race condition detailed in RFC 5407 section 3.1.2.
1991                                                  * We sent a CANCEL at the same time that the UAS sent us a 200 OK for
1992                                                  * the original INVITE. As a result, we have now received a 200 OK for
1993                                                  * a cancelled call. Our role is to immediately send a BYE to end the
1994                                                  * dialog.
1995                                                  */
1996                                                 pjsip_tx_data *tdata;
1997
1998                                                 if (pjsip_inv_end_session(inv, 500, NULL, &tdata) == PJ_SUCCESS) {
1999                                                         ast_sip_session_send_request(session, tdata);
2000                                                 }
2001                                         }
2002                                 }
2003                         }
2004                 } else {
2005                         if (tsx->role == PJSIP_ROLE_UAS && tsx->state == PJSIP_TSX_STATE_TRYING) {
2006                                 handle_incoming_request(session, e->body.tsx_state.src.rdata);
2007                         }
2008                 }
2009                 if ((cb = ast_sip_mod_data_get(tsx->mod_data, session_module.id,
2010                                                MOD_DATA_ON_RESPONSE))) {
2011                         cb(session, e->body.tsx_state.src.rdata);
2012                 }
2013         case PJSIP_EVENT_TRANSPORT_ERROR:
2014         case PJSIP_EVENT_TIMER:
2015         case PJSIP_EVENT_USER:
2016         case PJSIP_EVENT_UNKNOWN:
2017         case PJSIP_EVENT_TSX_STATE:
2018                 /* Inception? */
2019                 break;
2020         }
2021
2022         /* Terminated INVITE transactions always should result in queuing delayed requests,
2023          * no matter what event caused the transaction to terminate
2024          */
2025         if (tsx->method.id == PJSIP_INVITE_METHOD && tsx->state == PJSIP_TSX_STATE_TERMINATED) {
2026                 queue_delayed_request(session);
2027         }
2028 }
2029
2030 static int add_sdp_streams(void *obj, void *arg, void *data, int flags)
2031 {
2032         struct ast_sip_session_media *session_media = obj;
2033         pjmedia_sdp_session *answer = arg;
2034         struct ast_sip_session *session = data;
2035         struct ast_sip_session_sdp_handler *handler = session_media->handler;
2036         RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
2037         int res;
2038
2039         if (handler) {
2040                 /* if an already assigned handler does not handle the session_media or reports a catastrophic error, fail */
2041                 res = handler->create_outgoing_sdp_stream(session, session_media, answer);
2042                 if (res <= 0) {
2043                         return 0;
2044                 }
2045                 return CMP_MATCH;
2046         }
2047
2048         handler_list = ao2_find(sdp_handlers, session_media->stream_type, OBJ_KEY);
2049         if (!handler_list) {
2050                 return CMP_MATCH;
2051         }
2052
2053         /* no handler for this stream type and we have a list to search */
2054         AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
2055                 res = handler->create_outgoing_sdp_stream(session, session_media, answer);
2056                 if (res < 0) {
2057                         /* catastrophic error */
2058                         return 0;
2059                 }
2060                 if (res > 0) {
2061                         /* Handled by this handler. Move to the next stream */
2062                         session_media->handler = handler;
2063                         return CMP_MATCH;
2064                 }
2065         }
2066
2067         /* streams that weren't handled won't be included in generated outbound SDP */
2068         return CMP_MATCH;
2069 }
2070
2071 static struct pjmedia_sdp_session *create_local_sdp(pjsip_inv_session *inv, struct ast_sip_session *session, const pjmedia_sdp_session *offer)
2072 {
2073         RAII_VAR(struct ao2_iterator *, successful, NULL, ao2_iterator_cleanup);
2074         static const pj_str_t STR_IN = { "IN", 2 };
2075         static const pj_str_t STR_IP4 = { "IP4", 3 };
2076         static const pj_str_t STR_IP6 = { "IP6", 3 };
2077         pjmedia_sdp_session *local;
2078
2079         if (!(local = PJ_POOL_ZALLOC_T(inv->pool_prov, pjmedia_sdp_session))) {
2080                 return NULL;
2081         }
2082
2083         if (!offer) {
2084                 local->origin.version = local->origin.id = (pj_uint32_t)(ast_random());
2085         } else {
2086                 local->origin.version = offer->origin.version + 1;
2087                 local->origin.id = offer->origin.id;
2088         }
2089
2090         pj_strdup2(inv->pool, &local->origin.user, session->endpoint->media.sdpowner);
2091         local->origin.net_type = STR_IN;
2092         local->origin.addr_type = session->endpoint->media.rtp.ipv6 ? STR_IP6 : STR_IP4;
2093         local->origin.addr = *hostname;
2094         pj_strdup2(inv->pool, &local->name, session->endpoint->media.sdpsession);
2095
2096         /* Now let the handlers add streams of various types, pjmedia will automatically reorder the media streams for us */
2097         successful = ao2_callback_data(session->media, OBJ_MULTIPLE, add_sdp_streams, local, session);
2098         if (!successful || ao2_iterator_count(successful) != ao2_container_count(session->media)) {
2099                 /* Something experienced a catastrophic failure */
2100                 return NULL;
2101         }
2102
2103         /* Use the connection details of the first media stream if possible for SDP level */
2104         if (local->media_count) {
2105                 local->conn = local->media[0]->conn;
2106         }
2107
2108         return local;
2109 }
2110
2111 static void session_inv_on_rx_offer(pjsip_inv_session *inv, const pjmedia_sdp_session *offer)
2112 {
2113         struct ast_sip_session *session = inv->mod_data[session_module.id];
2114         pjmedia_sdp_session *answer;
2115
2116         if (handle_incoming_sdp(session, offer)) {
2117                 return;
2118         }
2119
2120         if ((answer = create_local_sdp(inv, session, offer))) {
2121                 pjsip_inv_set_sdp_answer(inv, answer);
2122         }
2123 }
2124
2125 #if 0
2126 static void session_inv_on_create_offer(pjsip_inv_session *inv, pjmedia_sdp_session **p_offer)
2127 {
2128         /* XXX STUB */
2129 }
2130 #endif
2131
2132 static void session_inv_on_media_update(pjsip_inv_session *inv, pj_status_t status)
2133 {
2134         struct ast_sip_session *session = inv->mod_data[session_module.id];
2135         const pjmedia_sdp_session *local, *remote;
2136
2137         if (!session->channel) {
2138                 /* If we don't have a channel. We really don't care about media updates.
2139                  * Just ignore
2140                  */
2141                 return;
2142         }
2143
2144         if ((status != PJ_SUCCESS) || (pjmedia_sdp_neg_get_active_local(inv->neg, &local) != PJ_SUCCESS) ||
2145                 (pjmedia_sdp_neg_get_active_remote(inv->neg, &remote) != PJ_SUCCESS)) {
2146                 ast_channel_hangupcause_set(session->channel, AST_CAUSE_BEARERCAPABILITY_NOTAVAIL);
2147                 ast_set_hangupsource(session->channel, ast_channel_name(session->channel), 0);
2148                 ast_queue_hangup(session->channel);
2149                 return;
2150         }
2151
2152         handle_negotiated_sdp(session, local, remote);
2153 }
2154
2155 static pjsip_redirect_op session_inv_on_redirected(pjsip_inv_session *inv, const pjsip_uri *target, const pjsip_event *e)
2156 {
2157         struct ast_sip_session *session = inv->mod_data[session_module.id];
2158         const pjsip_sip_uri *uri;
2159
2160         if (session->endpoint->redirect_method == AST_SIP_REDIRECT_URI_PJSIP) {
2161                 return PJSIP_REDIRECT_ACCEPT;
2162         }
2163
2164         if (!PJSIP_URI_SCHEME_IS_SIP(target) && !PJSIP_URI_SCHEME_IS_SIPS(target)) {
2165                 return PJSIP_REDIRECT_STOP;
2166         }
2167
2168         uri = pjsip_uri_get_uri(target);
2169
2170         if (session->endpoint->redirect_method == AST_SIP_REDIRECT_USER) {
2171                 char exten[AST_MAX_EXTENSION];
2172
2173                 ast_copy_pj_str(exten, &uri->user, sizeof(exten));
2174                 ast_channel_call_forward_set(session->channel, exten);
2175         } else if (session->endpoint->redirect_method == AST_SIP_REDIRECT_URI_CORE) {
2176                 char target_uri[PJSIP_MAX_URL_SIZE];
2177                 /* PJSIP/ + endpoint length + / + max URL size */
2178                 char forward[8 + strlen(ast_sorcery_object_get_id(session->endpoint)) + PJSIP_MAX_URL_SIZE];
2179
2180                 pjsip_uri_print(PJSIP_URI_IN_REQ_URI, uri, target_uri, sizeof(target_uri));
2181                 sprintf(forward, "PJSIP/%s/%s", ast_sorcery_object_get_id(session->endpoint), target_uri);
2182                 ast_channel_call_forward_set(session->channel, forward);
2183         }
2184
2185         return PJSIP_REDIRECT_STOP;
2186 }
2187
2188 static pjsip_inv_callback inv_callback = {
2189         .on_state_changed = session_inv_on_state_changed,
2190         .on_new_session = session_inv_on_new_session,
2191         .on_tsx_state_changed = session_inv_on_tsx_state_changed,
2192         .on_rx_offer = session_inv_on_rx_offer,
2193         .on_media_update = session_inv_on_media_update,
2194         .on_redirected = session_inv_on_redirected,
2195 };
2196
2197 /*! \brief Hook for modifying outgoing messages with SDP to contain the proper address information */
2198 static void session_outgoing_nat_hook(pjsip_tx_data *tdata, struct ast_sip_transport *transport)
2199 {
2200         struct ast_sip_nat_hook *hook = ast_sip_mod_data_get(
2201                 tdata->mod_data, session_module.id, MOD_DATA_NAT_HOOK);
2202         struct pjmedia_sdp_session *sdp;
2203         int stream;
2204
2205         /* SDP produced by us directly will never be multipart */
2206         if (hook || !tdata->msg->body || pj_stricmp2(&tdata->msg->body->content_type.type, "application") ||
2207                 pj_stricmp2(&tdata->msg->body->content_type.subtype, "sdp") || ast_strlen_zero(transport->external_media_address)) {
2208                 return;
2209         }
2210
2211         sdp = tdata->msg->body->data;
2212
2213         if (sdp->conn) {
2214                 char host[NI_MAXHOST];
2215                 struct ast_sockaddr addr = { { 0, } };
2216
2217                 ast_copy_pj_str(host, &sdp->conn->addr, sizeof(host));
2218                 ast_sockaddr_parse(&addr, host, PARSE_PORT_FORBID);
2219
2220                 if (ast_apply_ha(transport->localnet, &addr) != AST_SENSE_ALLOW) {
2221                         pj_strdup2(tdata->pool, &sdp->conn->addr, transport->external_media_address);
2222                 }
2223         }
2224
2225         for (stream = 0; stream < sdp->media_count; ++stream) {
2226                 /* See if there are registered handlers for this media stream type */
2227                 char media[20];
2228                 struct ast_sip_session_sdp_handler *handler;
2229                 RAII_VAR(struct sdp_handler_list *, handler_list, NULL, ao2_cleanup);
2230
2231                 /* We need a null-terminated version of the media string */
2232                 ast_copy_pj_str(media, &sdp->media[stream]->desc.media, sizeof(media));
2233
2234                 handler_list = ao2_find(sdp_handlers, media, OBJ_KEY);
2235                 if (!handler_list) {
2236                         ast_debug(1, "No registered SDP handlers for media type '%s'\n", media);
2237                         continue;
2238                 }
2239                 AST_LIST_TRAVERSE(&handler_list->list, handler, next) {
2240                         if (handler->change_outgoing_sdp_stream_media_address) {
2241                                 handler->change_outgoing_sdp_stream_media_address(tdata, sdp->media[stream], transport);
2242                         }
2243                 }
2244         }
2245
2246         /* We purposely do this so that the hook will not be invoked multiple times, ie: if a retransmit occurs */
2247         ast_sip_mod_data_set(tdata->pool, tdata->mod_data, session_module.id, MOD_DATA_NAT_HOOK, nat_hook);
2248 }
2249
2250 static int load_module(void)
2251 {
2252         pjsip_endpoint *endpt;
2253         if (!ast_sip_get_sorcery() || !ast_sip_get_pjsip_endpoint()) {
2254                 return AST_MODULE_LOAD_DECLINE;
2255         }
2256         if (!(nat_hook = ast_sorcery_alloc(ast_sip_get_sorcery(), "nat_hook", NULL))) {
2257                 return AST_MODULE_LOAD_DECLINE;
2258         }
2259         nat_hook->outgoing_external_message = session_outgoing_nat_hook;
2260         ast_sorcery_create(ast_sip_get_sorcery(), nat_hook);
2261         sdp_handlers = ao2_container_alloc(SDP_HANDLER_BUCKETS,
2262                         sdp_handler_list_hash, sdp_handler_list_cmp);
2263         if (!sdp_handlers) {
2264                 return AST_MODULE_LOAD_DECLINE;
2265         }
2266         endpt = ast_sip_get_pjsip_endpoint();
2267         pjsip_inv_usage_init(endpt, &inv_callback);
2268         pjsip_100rel_init_module(endpt);
2269         pjsip_timer_init_module(endpt);
2270         hostname = pj_gethostname();
2271         if (ast_sip_register_service(&session_module)) {
2272                 return AST_MODULE_LOAD_DECLINE;
2273         }
2274         ast_sip_register_service(&session_reinvite_module);
2275
2276         ast_module_ref(ast_module_info->self);
2277
2278         return AST_MODULE_LOAD_SUCCESS;
2279 }
2280
2281 static int unload_module(void)
2282 {
2283         /* This will never get called as this module can't be unloaded */
2284         return 0;
2285 }
2286
2287 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "PJSIP Session resource",
2288                 .support_level = AST_MODULE_SUPPORT_CORE,
2289                 .load = load_module,
2290                 .unload = unload_module,
2291                 .load_pri = AST_MODPRI_APP_DEPEND,
2292                );