src/purple/purple-media.c

   1 /**
   2  * @file purple-media.c
   3  *
   4  * pidgin-sipe
   5  *
   6  * Copyright (C) 2010-2019 SIPE Project <http://sipe.sourceforge.net/>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include "glib.h"
  28 #include "glib/gstdio.h"
  29 #include <fcntl.h>
  30 #include <string.h>
  31 #ifdef HAVE_UNISTD_H
  32 #include <unistd.h>
  33 #endif
  34
  35 #include "sipe-common.h"
  36
  37 #include "mediamanager.h"
  38 #include "agent.h"
  39 #include "version.h"
  40
  41 #ifdef _WIN32
  42 /* wrappers for write() & friends for socket handling */
  43 #include "win32/win32dep.h"
  44 #endif
  45
  46 #if PURPLE_VERSION_CHECK(3,0,0)
  47 /* nothing here yet */
  48 #else
  49 #define purple_config_dir purple_user_dir
  50 #endif
  51
  52 #include "sipe-backend.h"
  53 #include "sipe-core.h"
  54
  55 #include "purple-private.h"
  56
  57 /*
  58  * GStreamer interfaces fail to compile on ARM architecture with -Wcast-align
  59  *
  60  * Diagnostic #pragma was added in GCC 4.2.0
  61  */
  62 #if defined(__GNUC__)
  63 #if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 2)) || (__GNUC__ >= 5)
  64 #if defined(__ARMEL__) || defined(__ARMEB__) || defined(__hppa__) || defined(__mips__) || defined(__sparc__) || (defined(__powerpc__) && defined(__NO_FPRS__))
  65 #pragma GCC diagnostic ignored "-Wcast-align"
  66 #endif
  67 #endif
  68 #endif
  69
  70 #include "media-gst.h"
  71 #include <gst/rtp/gstrtcpbuffer.h>
  72 #include <farstream/fs-session.h>
  73
  74 struct sipe_backend_media {
  75         PurpleMedia *m;
  76         /**
  77          * Number of media streams that were not yet locally accepted or rejected.
  78          */
  79         guint unconfirmed_streams;
  80 };
  81
  82 struct sipe_backend_media_stream {
  83         gboolean local_on_hold;
  84         gboolean remote_on_hold;
  85         gboolean accepted;
  86         gboolean initialized_cb_was_fired;
  87
  88         gulong gst_bus_cb_id;
  89
  90         GObject *rtpsession;
  91         gulong on_sending_rtcp_cb_id;
  92 };
  93
  94 void
  95 sipe_backend_media_stream_free(struct sipe_backend_media_stream *stream)
  96 {
  97         if (stream->gst_bus_cb_id != 0) {
  98                 GstElement *pipe;
  99
 100                 pipe = purple_media_manager_get_pipeline(
 101                                 purple_media_manager_get());
 102                 if (pipe) {
 103                         GstBus *bus;
 104
 105                         bus = gst_element_get_bus(pipe);
 106                         g_signal_handler_disconnect(bus, stream->gst_bus_cb_id);
 107                         stream->gst_bus_cb_id = 0;
 108                         gst_object_unref(bus);
 109                 }
 110         }
 111
 112         if (stream->rtpsession) {
 113                 g_clear_object(&stream->rtpsession);
 114         }
 115
 116         g_free(stream);
 117 }
 118
 119 static PurpleMediaSessionType sipe_media_to_purple(SipeMediaType type);
 120 static PurpleMediaCandidateType sipe_candidate_type_to_purple(SipeCandidateType type);
 121 static SipeCandidateType purple_candidate_type_to_sipe(PurpleMediaCandidateType type);
 122 static PurpleMediaNetworkProtocol sipe_network_protocol_to_purple(SipeNetworkProtocol proto);
 123 static SipeNetworkProtocol purple_network_protocol_to_sipe(PurpleMediaNetworkProtocol proto);
 124
 125 static void
 126 maybe_signal_stream_initialized(struct sipe_media_call *call, gchar *sessionid)
 127 {
 128         if (call->stream_initialized_cb) {
 129                 struct sipe_media_stream *stream;
 130                 stream = sipe_core_media_get_stream_by_id(call, sessionid);
 131
 132                 if (stream &&
 133                     sipe_backend_stream_initialized(call, stream) &&
 134                     !stream->backend_private->initialized_cb_was_fired) {
 135                         stream->backend_private->initialized_cb_was_fired = TRUE;
 136                         call->stream_initialized_cb(call, stream);
 137                 }
 138         }
 139 }
 140
 141 static void
 142 on_candidates_prepared_cb(SIPE_UNUSED_PARAMETER PurpleMedia *media,
 143                           gchar *sessionid,
 144                           SIPE_UNUSED_PARAMETER gchar *participant,
 145                           struct sipe_media_call *call)
 146 {
 147         maybe_signal_stream_initialized(call, sessionid);
 148 }
 149
 150 static void
 151 on_codecs_changed_cb(SIPE_UNUSED_PARAMETER PurpleMedia *media,
 152                     gchar *sessionid,
 153                     struct sipe_media_call *call)
 154 {
 155         maybe_signal_stream_initialized(call, sessionid);
 156 }
 157
 158 static void
 159 on_state_changed_cb(SIPE_UNUSED_PARAMETER PurpleMedia *media,
 160                     PurpleMediaState state,
 161                     gchar *sessionid,
 162                     gchar *participant,
 163                     struct sipe_media_call *call)
 164 {
 165         SIPE_DEBUG_INFO("sipe_media_state_changed_cb: %d %s %s\n", state, sessionid, participant);
 166
 167         if (state == PURPLE_MEDIA_STATE_CONNECTED && sessionid && participant) {
 168                 struct sipe_media_stream *stream;
 169
 170                 stream = sipe_core_media_get_stream_by_id(call, sessionid);
 171                 if (stream && stream->backend_private->rtpsession &&
 172                     stream->backend_private->on_sending_rtcp_cb_id != 0) {
 173                         struct sipe_backend_media_stream *backend_stream;
 174
 175                         SIPE_DEBUG_INFO_NOFORMAT("Peer started sending. Ceasing"
 176                                         " video source requests.");
 177
 178                         backend_stream = stream->backend_private;
 179
 180                         g_signal_handler_disconnect(backend_stream->rtpsession,
 181                                         backend_stream->on_sending_rtcp_cb_id);
 182                         g_clear_object(&backend_stream->rtpsession);
 183                         backend_stream->on_sending_rtcp_cb_id = 0;
 184                 }
 185         } else if (state == PURPLE_MEDIA_STATE_END) {
 186                 if (sessionid && participant) {
 187                         struct sipe_media_stream *stream =
 188                                         sipe_core_media_get_stream_by_id(call, sessionid);
 189                         if (stream) {
 190                                 sipe_core_media_stream_end(stream);
 191                         }
 192                 } else if (!sessionid && !participant && call->media_end_cb) {
 193                         call->media_end_cb(call);
 194                 }
 195         }
 196 }
 197
 198 void
 199 capture_pipeline(const gchar *label) {
 200         PurpleMediaManager *manager = purple_media_manager_get();
 201         GstElement *pipeline = purple_media_manager_get_pipeline(manager);
 202         GST_DEBUG_BIN_TO_DOT_FILE_WITH_TS(GST_BIN(pipeline), GST_DEBUG_GRAPH_SHOW_ALL, label);
 203 }
 204
 205 static void
 206 on_error_cb(SIPE_UNUSED_PARAMETER PurpleMedia *media, gchar *message,
 207             struct sipe_media_call *call)
 208 {
 209         capture_pipeline("ERROR");
 210
 211         if (call->error_cb)
 212                 call->error_cb(call, message);
 213 }
 214
 215 static void
 216 on_stream_info_cb(PurpleMedia *media,
 217                   PurpleMediaInfoType type,
 218                   gchar *sessionid,
 219                   gchar *participant,
 220                   gboolean local,
 221                   struct sipe_media_call *call)
 222 {
 223         if (type == PURPLE_MEDIA_INFO_ACCEPT) {
 224                 if (call->call_accept_cb && !sessionid && !participant)
 225                         call->call_accept_cb(call, local);
 226                 else if (sessionid && participant) {
 227                         struct sipe_media_stream *stream;
 228                         stream = sipe_core_media_get_stream_by_id(call, sessionid);
 229                         if (stream) {
 230                                 if (!stream->backend_private->accepted && local)
 231                                          --call->backend_private->unconfirmed_streams;
 232                                 stream->backend_private->accepted = TRUE;
 233                         }
 234                 }
 235         } else if (type == PURPLE_MEDIA_INFO_HOLD || type == PURPLE_MEDIA_INFO_UNHOLD) {
 236
 237                 gboolean state = (type == PURPLE_MEDIA_INFO_HOLD);
 238
 239                 if (sessionid) {
 240                         // Hold specific stream
 241                         struct sipe_media_stream *stream;
 242                         stream = sipe_core_media_get_stream_by_id(call, sessionid);
 243
 244                         if (stream) {
 245                                 if (local)
 246                                         stream->backend_private->local_on_hold = state;
 247                                 else
 248                                         stream->backend_private->remote_on_hold = state;
 249                         }
 250                 } else {
 251                         // Hold all streams
 252                         GList *session_ids = purple_media_get_session_ids(media);
 253
 254                         for (; session_ids; session_ids = session_ids->next) {
 255                                 struct sipe_media_stream *stream =
 256                                                 sipe_core_media_get_stream_by_id(call, session_ids->data);
 257
 258                                 if (stream) {
 259                                         if (local)
 260                                                 stream->backend_private->local_on_hold = state;
 261                                         else
 262                                                 stream->backend_private->remote_on_hold = state;
 263                                 }
 264                         }
 265
 266                         g_list_free(session_ids);
 267                 }
 268
 269                 if (call->call_hold_cb)
 270                         call->call_hold_cb(call, local, state);
 271         } else if (type == PURPLE_MEDIA_INFO_HANGUP || type == PURPLE_MEDIA_INFO_REJECT) {
 272                 if (!sessionid && !participant) {
 273                         if (type == PURPLE_MEDIA_INFO_HANGUP && call->call_hangup_cb)
 274                                 call->call_hangup_cb(call, local);
 275                         else if (type == PURPLE_MEDIA_INFO_REJECT && call->call_reject_cb && !local)
 276                                 call->call_reject_cb(call, local);
 277                 } else if (sessionid && participant) {
 278                         struct sipe_media_stream *stream;
 279                         stream = sipe_core_media_get_stream_by_id(call, sessionid);
 280
 281 #ifdef HAVE_XDATA
 282                         purple_media_manager_set_application_data_callbacks(
 283                                         purple_media_manager_get(), media,
 284                                         sessionid, participant, NULL, NULL, NULL);
 285 #endif
 286
 287                         if (stream) {
 288                                 if (local && --call->backend_private->unconfirmed_streams == 0 &&
 289                                     call->call_reject_cb)
 290                                         call->call_reject_cb(call, local);
 291                         }
 292                 }
 293         } else if (type == PURPLE_MEDIA_INFO_MUTE || type == PURPLE_MEDIA_INFO_UNMUTE) {
 294                 struct sipe_media_stream *stream =
 295                                 sipe_core_media_get_stream_by_id(call, "audio");
 296
 297                 if (stream && stream->mute_cb) {
 298                         stream->mute_cb(stream, type == PURPLE_MEDIA_INFO_MUTE);
 299                 }
 300         }
 301 }
 302
 303 static void
 304 on_candidate_pair_established_cb(SIPE_UNUSED_PARAMETER PurpleMedia *media,
 305                                  const gchar *sessionid,
 306                                  SIPE_UNUSED_PARAMETER const gchar *participant,
 307                                  SIPE_UNUSED_PARAMETER PurpleMediaCandidate *local_candidate,
 308                                  SIPE_UNUSED_PARAMETER PurpleMediaCandidate *remote_candidate,
 309                                  struct sipe_media_call *call)
 310 {
 311         struct sipe_media_stream *stream =
 312                         sipe_core_media_get_stream_by_id(call, sessionid);
 313
 314         if (!stream) {
 315                 return;
 316         }
 317
 318 #ifdef HAVE_PURPLE_NEW_TCP_ENUMS
 319         if (purple_media_candidate_get_protocol(local_candidate) != PURPLE_MEDIA_NETWORK_PROTOCOL_UDP) {
 320                 purple_media_set_send_rtcp_mux(media, sessionid, participant, TRUE);
 321         }
 322 #endif
 323
 324         sipe_core_media_stream_candidate_pair_established(stream);
 325 }
 326
 327 struct sipe_backend_media *
 328 sipe_backend_media_new(struct sipe_core_public *sipe_public,
 329                        struct sipe_media_call *call,
 330                        const gchar *participant,
 331                        SipeMediaCallFlags flags)
 332 {
 333         struct sipe_backend_media *media = g_new0(struct sipe_backend_media, 1);
 334         struct sipe_backend_private *purple_private = sipe_public->backend_private;
 335         PurpleMediaManager *manager = purple_media_manager_get();
 336         GstElement *pipeline;
 337
 338         if (flags & SIPE_MEDIA_CALL_NO_UI) {
 339 #ifdef HAVE_XDATA
 340                 media->m = purple_media_manager_create_private_media(manager,
 341                                 purple_private->account, "fsrtpconference",
 342                                 participant, flags & SIPE_MEDIA_CALL_INITIATOR);
 343 #else
 344                 SIPE_DEBUG_ERROR_NOFORMAT("Purple doesn't support private media");
 345 #endif
 346         } else {
 347                 media->m = purple_media_manager_create_media(manager,
 348                                 purple_private->account, "fsrtpconference",
 349                                 participant, flags & SIPE_MEDIA_CALL_INITIATOR);
 350         }
 351
 352         g_signal_connect(G_OBJECT(media->m), "candidates-prepared",
 353                          G_CALLBACK(on_candidates_prepared_cb), call);
 354         g_signal_connect(G_OBJECT(media->m), "codecs-changed",
 355                          G_CALLBACK(on_codecs_changed_cb), call);
 356         g_signal_connect(G_OBJECT(media->m), "stream-info",
 357                          G_CALLBACK(on_stream_info_cb), call);
 358         g_signal_connect(G_OBJECT(media->m), "error",
 359                          G_CALLBACK(on_error_cb), call);
 360         g_signal_connect(G_OBJECT(media->m), "state-changed",
 361                          G_CALLBACK(on_state_changed_cb), call);
 362         g_signal_connect(G_OBJECT(media->m), "candidate-pair-established",
 363                          G_CALLBACK(on_candidate_pair_established_cb), call);
 364
 365
 366         /* On error, the pipeline is no longer in PLAYING state and libpurple
 367          * will not switch it back to PLAYING, preventing any more calls until
 368          * application restart. We switch the state ourselves here to negate
 369          * effect of any error in previous call (if any). */
 370         pipeline = purple_media_manager_get_pipeline(manager);
 371         gst_element_set_state(pipeline, GST_STATE_PLAYING);
 372
 373         return media;
 374 }
 375
 376 void
 377 sipe_backend_media_free(struct sipe_backend_media *media)
 378 {
 379         g_free(media);
 380 }
 381
 382 void
 383 sipe_backend_media_set_cname(struct sipe_backend_media *media, gchar *cname)
 384 {
 385         if (media) {
 386                 guint num_params = 3;
 387                 GParameter *params = g_new0(GParameter, num_params);
 388                 params[0].name = "sdes-cname";
 389                 g_value_init(&params[0].value, G_TYPE_STRING);
 390                 g_value_set_string(&params[0].value, cname);
 391                 params[1].name = "sdes-name";
 392                 g_value_init(&params[1].value, G_TYPE_STRING);
 393                 params[2].name = "sdes-tool";
 394                 g_value_init(&params[2].value, G_TYPE_STRING);
 395
 396                 purple_media_set_params(media->m, num_params, params);
 397
 398                 g_value_unset(&params[0].value);
 399                 g_free(params);
 400         }
 401 }
 402
 403 #define FS_CODECS_CONF \
 404         "# Automatically created by SIPE plugin\n" \
 405         "[video/H264]\n" \
 406         "farstream-send-profile=videoscale ! videoconvert ! fsvideoanyrate ! x264enc ! video/x-h264,profile=constrained-baseline ! rtph264pay\n" \
 407         "\n" \
 408         "[application/X-DATA]\n" \
 409         "id=127\n"
 410
 411 static void
 412 ensure_codecs_conf()
 413 {
 414         gchar *filename;
 415         const gchar *fs_codecs_conf = FS_CODECS_CONF;
 416         GError *error = NULL;
 417
 418         filename = g_build_filename(purple_config_dir(), "fs-codec.conf", NULL);
 419
 420         g_file_set_contents(filename, fs_codecs_conf, strlen(fs_codecs_conf),
 421                             &error);
 422         if (error) {
 423                 SIPE_DEBUG_ERROR("Couldn't create fs-codec.conf: %s",
 424                                  error->message);
 425                 g_error_free(error);
 426         }
 427
 428         g_free(filename);
 429 }
 430
 431 static void
 432 append_relay(struct sipe_backend_media_relays *relay_info, const gchar *ip,
 433              guint port, const gchar *type, gchar *username, gchar *password)
 434 {
 435         GstStructure *gst_relay_info;
 436
 437         gst_relay_info = gst_structure_new("relay-info",
 438                         "ip", G_TYPE_STRING, ip,
 439                         "port", G_TYPE_UINT, port,
 440                         "relay-type", G_TYPE_STRING, type,
 441                         "username", G_TYPE_STRING, username,
 442                         "password", G_TYPE_STRING, password,
 443                         NULL);
 444
 445         if (gst_relay_info) {
 446                 g_ptr_array_add((GPtrArray *)relay_info, gst_relay_info);
 447         }
 448 }
 449
 450 struct sipe_backend_media_relays *
 451 sipe_backend_media_relays_convert(GSList *media_relays, gchar *username, gchar *password)
 452 {
 453         struct sipe_backend_media_relays *relay_info;
 454
 455         relay_info = (struct sipe_backend_media_relays *)
 456                         g_ptr_array_new_with_free_func((GDestroyNotify) gst_structure_free);
 457
 458         for (; media_relays; media_relays = media_relays->next) {\
 459                 struct sipe_media_relay *relay = media_relays->data;
 460
 461                 /* Skip relays where IP could not be resolved. */
 462                 if (!relay->hostname)
 463                         continue;
 464
 465                 if (relay->udp_port != 0)
 466                         append_relay(relay_info, relay->hostname, relay->udp_port,
 467                                      "udp", username, password);
 468
 469 #ifdef HAVE_PURPLE_NEW_TCP_ENUMS
 470                 if (relay->tcp_port != 0) {
 471                         const gchar *type = "tcp";
 472                         if (relay->tcp_port == 443)
 473                                 type = "tls";
 474                         append_relay(relay_info, relay->hostname, relay->tcp_port,
 475                                      type, username, password);
 476                 }
 477 #endif
 478         }
 479
 480         return relay_info;
 481 }
 482
 483 void
 484 sipe_backend_media_relays_free(struct sipe_backend_media_relays *media_relays)
 485 {
 486         g_ptr_array_unref((GPtrArray *)media_relays);
 487 }
 488
 489 #ifdef HAVE_XDATA
 490 static void
 491 stream_readable_cb(SIPE_UNUSED_PARAMETER PurpleMediaManager *manager,
 492                  SIPE_UNUSED_PARAMETER PurpleMedia *media,
 493                  const gchar *session_id,
 494                  SIPE_UNUSED_PARAMETER const gchar *participant,
 495                  gpointer user_data)
 496 {
 497         struct sipe_media_call *call = (struct sipe_media_call *)user_data;
 498         struct sipe_media_stream *stream;
 499
 500         SIPE_DEBUG_INFO("stream_readable_cb: %s is readable", session_id);
 501
 502         stream = sipe_core_media_get_stream_by_id(call, session_id);
 503
 504         if (stream) {
 505                 sipe_core_media_stream_readable(stream);
 506         }
 507 }
 508
 509 gssize
 510 sipe_backend_media_stream_read(struct sipe_media_stream *stream,
 511                                guint8 *buffer, gsize len)
 512 {
 513         return purple_media_manager_receive_application_data(
 514                         purple_media_manager_get(),
 515                         stream->call->backend_private->m,
 516                         stream->id, stream->call->with, buffer, len, FALSE);
 517 }
 518
 519 gssize
 520 sipe_backend_media_stream_write(struct sipe_media_stream *stream,
 521                                 guint8 *buffer, gsize len)
 522 {
 523         return purple_media_manager_send_application_data(
 524                         purple_media_manager_get(),
 525                         stream->call->backend_private->m,
 526                         stream->id, stream->call->with, buffer, len, FALSE);
 527 }
 528
 529 static void
 530 stream_writable_cb(SIPE_UNUSED_PARAMETER PurpleMediaManager *manager,
 531                    SIPE_UNUSED_PARAMETER PurpleMedia *media,
 532                    const gchar *session_id,
 533                    SIPE_UNUSED_PARAMETER const gchar *participant,
 534                    gboolean writable,
 535                    gpointer user_data)
 536 {
 537         struct sipe_media_call *call = (struct sipe_media_call *)user_data;
 538         struct sipe_media_stream *stream;
 539
 540         stream = sipe_core_media_get_stream_by_id(call, session_id);
 541
 542         if (!stream) {
 543                 SIPE_DEBUG_ERROR("stream_writable_cb: stream %s not found!",
 544                                  session_id);
 545                 return;
 546         }
 547
 548         SIPE_DEBUG_INFO("stream_writable_cb: %s has become %swritable",
 549                         session_id, writable ? "" : "not ");
 550
 551         sipe_core_media_stream_writable(stream, writable);
 552 }
 553 #endif
 554
 555 static gboolean
 556 write_ms_h264_video_source_request(GstRTCPBuffer *buffer, guint32 ssrc,
 557                                    guint8 payload_type)
 558 {
 559         GstRTCPPacket packet;
 560         guint8 *fci_data;
 561
 562         if (!gst_rtcp_buffer_add_packet(buffer, GST_RTCP_TYPE_PSFB, &packet)) {
 563                 return FALSE;
 564         }
 565
 566         gst_rtcp_packet_fb_set_type(&packet, GST_RTCP_PSFB_TYPE_AFB);
 567         gst_rtcp_packet_fb_set_sender_ssrc(&packet, ssrc);
 568         gst_rtcp_packet_fb_set_media_ssrc(&packet, SIPE_MSRTP_VSR_SOURCE_ANY);
 569
 570         if (!gst_rtcp_packet_fb_set_fci_length(&packet,
 571                                                SIPE_MSRTP_VSR_FCI_WORDLEN)) {
 572                 gst_rtcp_packet_remove(&packet);
 573                 return FALSE;
 574         }
 575
 576         fci_data = gst_rtcp_packet_fb_get_fci(&packet);
 577
 578         sipe_core_msrtp_write_video_source_request(fci_data, payload_type);
 579
 580         return TRUE;
 581 }
 582
 583 static gboolean
 584 on_sending_rtcp_cb(SIPE_UNUSED_PARAMETER GObject *rtpsession,
 585                    GstBuffer *buffer,
 586                    SIPE_UNUSED_PARAMETER gboolean is_early,
 587                    FsSession *fssession)
 588 {
 589         gboolean was_changed = FALSE;
 590         FsCodec *send_codec;
 591
 592         g_object_get(fssession, "current-send-codec", &send_codec, NULL);
 593         if (!send_codec) {
 594                 return FALSE;
 595         }
 596
 597         if (sipe_strequal(send_codec->encoding_name, "H264")) {
 598                 GstRTCPBuffer rtcp_buffer = GST_RTCP_BUFFER_INIT;
 599                 guint32 ssrc;
 600
 601                 g_object_get(fssession, "ssrc", &ssrc, NULL);
 602
 603                 gst_rtcp_buffer_map(buffer, GST_MAP_READWRITE, &rtcp_buffer);
 604                 was_changed = write_ms_h264_video_source_request(&rtcp_buffer,
 605                                 ssrc, send_codec->id);
 606                 gst_rtcp_buffer_unmap(&rtcp_buffer);
 607         }
 608
 609         fs_codec_destroy(send_codec);
 610
 611         return was_changed;
 612 }
 613
 614 static GstPadProbeReturn
 615 h264_buffer_cb(SIPE_UNUSED_PARAMETER GstPad *pad, GstPadProbeInfo *info,
 616                SIPE_UNUSED_PARAMETER gpointer user_data)
 617 {
 618         GstBuffer *buffer;
 619         GstMemory *memory;
 620         GstMapInfo map;
 621         guint8 *data;
 622         guint8 nal_count = 0;
 623         gsize pacsi_len;
 624
 625         buffer = gst_pad_probe_info_get_buffer(info);
 626
 627         // Count NALs in the buffer
 628         gst_buffer_map(buffer, &map, GST_MAP_READ);
 629
 630         data = map.data;
 631         while (data < map.data + map.size) {
 632                 guint32 size = GST_READ_UINT32_BE(data);
 633                 data += GST_READ_UINT32_BE(data) + sizeof (size);
 634                 ++nal_count;
 635         }
 636
 637         gst_buffer_unmap(buffer, &map);
 638
 639         // Write PACSI (RFC6190 section 4.9)
 640         memory = gst_allocator_alloc(NULL, 100, NULL);
 641         gst_memory_map(memory, &map, GST_MAP_WRITE);
 642         pacsi_len = sipe_core_msrtp_write_video_scalability_info(map.data,
 643                                                                  nal_count);
 644         gst_memory_unmap(memory, &map);
 645         gst_memory_resize(memory, 0, pacsi_len);
 646
 647         buffer = gst_buffer_make_writable(buffer);
 648         gst_buffer_insert_memory(buffer, 0, memory);
 649         GST_PAD_PROBE_INFO_DATA(info) = buffer;
 650
 651         return GST_PAD_PROBE_OK;
 652 }
 653
 654 static gint
 655 find_payloader(GValue *value, GstCaps *rtpcaps)
 656 {
 657         gint result = 1;
 658         GstElement *element;
 659         GstPad *sinkpad;
 660         GstCaps *caps;
 661
 662         element = g_value_get_object(value);
 663         sinkpad = gst_element_get_static_pad(element, "sink");
 664         caps = gst_pad_query_caps(sinkpad, NULL);
 665
 666         /* Elements are iterated from the most downstream. We're looking for the
 667          * first that does NOT consume RTP frames. */
 668         result = gst_caps_can_intersect(caps, rtpcaps);
 669
 670         gst_caps_unref(caps);
 671         gst_object_unref(sinkpad);
 672
 673         return result;
 674 }
 675
 676 static void
 677 current_send_codec_changed_cb(FsSession *fssession,
 678                               SIPE_UNUSED_PARAMETER GParamSpec *pspec,
 679                               GstBin *fsconference)
 680 {
 681         FsCodec *send_codec;
 682
 683         g_object_get(fssession, "current-send-codec", &send_codec, NULL);
 684
 685         if (sipe_strequal(send_codec->encoding_name, "H264")) {
 686                 guint session_id;
 687                 gchar *sendbin_name;
 688                 GstBin *sendbin;
 689                 GstCaps *caps;
 690                 GstIterator *it;
 691                 GValue val = G_VALUE_INIT;
 692
 693                 g_object_get(fssession, "id", &session_id, NULL);
 694
 695                 sendbin_name = g_strdup_printf("send_%u_%u", session_id,
 696                                                send_codec->id);
 697
 698                 sendbin = GST_BIN(gst_bin_get_by_name(fsconference,
 699                                                       sendbin_name));
 700                 g_free(sendbin_name);
 701
 702                 if (!sendbin) {
 703                         SIPE_DEBUG_ERROR("Couldn't find Farstream send bin for "
 704                                          "session %d", session_id);
 705                         return;
 706                 }
 707
 708                 caps = gst_caps_new_empty_simple("application/x-rtp");
 709                 it = gst_bin_iterate_sorted(sendbin);
 710                 if (gst_iterator_find_custom(it, (GCompareFunc)find_payloader,
 711                                              &val, caps)) {
 712                         GstElement *payloader;
 713                         GstPad *sinkpad;
 714
 715                         payloader = g_value_get_object(&val);
 716                         sinkpad = gst_element_get_static_pad(payloader, "sink");
 717                         if (sinkpad) {
 718                                 gst_pad_add_probe(sinkpad,
 719                                                   GST_PAD_PROBE_TYPE_BUFFER,
 720                                                   h264_buffer_cb, NULL, NULL);
 721                                 gst_object_unref(sinkpad);
 722                         }
 723                         g_value_unset(&val);
 724                 }
 725                 gst_caps_unref(caps);
 726
 727                 gst_iterator_free(it);
 728                 gst_object_unref(sendbin);
 729         }
 730
 731         fs_codec_destroy(send_codec);
 732 }
 733
 734 static gint
 735 find_sinkpad(GValue *value, GstPad *fssession_sinkpad)
 736 {
 737         GstElement *tee_srcpad = g_value_get_object(value);
 738
 739         return !(GST_PAD_PEER(tee_srcpad) == fssession_sinkpad);
 740 }
 741
 742 static void
 743 gst_bus_cb(GstBus *bus, GstMessage *msg, struct sipe_media_stream *stream)
 744 {
 745         PurpleMedia *m;
 746         const GstStructure *s;
 747         FsSession *fssession;
 748         GstElement *tee;
 749         GstPad *sinkpad;
 750         GstIterator *it;
 751         GValue val = G_VALUE_INIT;
 752
 753         if (GST_MESSAGE_TYPE(msg) != GST_MESSAGE_ELEMENT) {
 754                 return;
 755         }
 756
 757         m = stream->call->backend_private->m;
 758
 759         s = gst_message_get_structure(msg);
 760         if (!gst_structure_has_name(s, "farstream-codecs-changed")) {
 761                 return;
 762         }
 763
 764         fssession = g_value_get_object(gst_structure_get_value(s, "session"));
 765         g_return_if_fail(fssession);
 766
 767         tee = purple_media_get_tee(m, stream->id, NULL);
 768         g_return_if_fail(tee);
 769
 770         g_object_get(fssession, "sink-pad", &sinkpad, NULL);
 771         g_return_if_fail(sinkpad);
 772
 773         /* Check whether this message is from the FsSession we're waiting for.
 774          * For this to be true, the tee we got from libpurple has to be linked
 775          * to "sink-pad" of the message's FsSession. */
 776         it = gst_element_iterate_src_pads(tee);
 777         if (gst_iterator_find_custom(it, (GCompareFunc)find_sinkpad, &val,
 778                                      sinkpad)) {
 779                 FsMediaType media_type;
 780
 781                 if (stream->ssrc_range) {
 782                         g_object_set(fssession, "ssrc",
 783                                      stream->ssrc_range->begin, NULL);
 784                 }
 785
 786                 g_object_get(fssession, "media-type", &media_type, NULL);
 787
 788                 if (media_type == FS_MEDIA_TYPE_VIDEO) {
 789                         GObject *rtpsession;
 790                         GstBin *fsconference;
 791
 792                         g_object_get(fssession,
 793                                      "internal-session", &rtpsession, NULL);
 794                         if (rtpsession) {
 795                                 stream->backend_private->rtpsession =
 796                                         gst_object_ref(rtpsession);
 797                                 stream->backend_private->on_sending_rtcp_cb_id =
 798                                         g_signal_connect(rtpsession,
 799                                                 "on-sending-rtcp",
 800                                                 G_CALLBACK(on_sending_rtcp_cb),
 801                                                 fssession);
 802
 803                                 g_object_unref (rtpsession);
 804                         }
 805
 806                         g_object_get(fssession,
 807                                      "conference", &fsconference, NULL);
 808
 809                         g_signal_connect_object(fssession,
 810                                 "notify::current-send-codec",
 811                                 G_CALLBACK(current_send_codec_changed_cb),
 812                                 fsconference, 0);
 813                         gst_object_unref(fsconference);
 814                 }
 815
 816                 g_signal_handler_disconnect(bus,
 817                                 stream->backend_private->gst_bus_cb_id);
 818                 stream->backend_private->gst_bus_cb_id = 0;
 819                 g_value_unset (&val);
 820         }
 821
 822         gst_iterator_free(it);
 823         gst_object_unref(sinkpad);
 824 }
 825
 826 struct sipe_backend_media_stream *
 827 sipe_backend_media_add_stream(struct sipe_media_stream *stream,
 828                               SipeMediaType type,
 829                               SipeIceVersion ice_version,
 830                               gboolean initiator,
 831                               struct sipe_backend_media_relays *media_relays,
 832                               guint min_port, guint max_port)
 833 {
 834         struct sipe_backend_media *media = stream->call->backend_private;
 835         struct sipe_backend_media_stream *backend_stream = NULL;
 836         GstElement *pipe;
 837         // Preallocate enough space for all potential parameters to fit.
 838         GParameter *params = g_new0(GParameter, 7);
 839         guint params_cnt = 0;
 840         const gchar *transmitter;
 841 #ifdef HAVE_XDATA
 842         PurpleMediaAppDataCallbacks callbacks = {
 843                         stream_readable_cb, stream_writable_cb
 844         };
 845 #endif
 846
 847         if (ice_version != SIPE_ICE_NO_ICE) {
 848                 transmitter = "nice";
 849
 850                 params[params_cnt].name = "compatibility-mode";
 851                 g_value_init(&params[params_cnt].value, G_TYPE_UINT);
 852                 g_value_set_uint(&params[params_cnt].value,
 853                                  ice_version == SIPE_ICE_DRAFT_6 ?
 854                                  NICE_COMPATIBILITY_OC2007 :
 855                                  NICE_COMPATIBILITY_OC2007R2);
 856                 ++params_cnt;
 857
 858                 if (min_port != 0) {
 859                         params[params_cnt].name = "min-port";
 860                         g_value_init(&params[params_cnt].value, G_TYPE_UINT);
 861                         g_value_set_uint(&params[params_cnt].value, min_port);
 862                         ++params_cnt;
 863                 }
 864
 865                 if (max_port != 0) {
 866                         params[params_cnt].name = "max-port";
 867                         g_value_init(&params[params_cnt].value, G_TYPE_UINT);
 868                         g_value_set_uint(&params[params_cnt].value, max_port);
 869                         ++params_cnt;
 870                 }
 871
 872                 if (media_relays) {
 873                         params[params_cnt].name = "relay-info";
 874                         g_value_init(&params[params_cnt].value, G_TYPE_PTR_ARRAY);
 875                         g_value_set_boxed(&params[params_cnt].value, media_relays);
 876                         ++params_cnt;
 877                 }
 878
 879                 if (type == SIPE_MEDIA_APPLICATION) {
 880                         params[params_cnt].name = "ice-udp";
 881                         g_value_init(&params[params_cnt].value, G_TYPE_BOOLEAN);
 882                         g_value_set_boolean(&params[params_cnt].value, FALSE);
 883                         ++params_cnt;
 884
 885                         params[params_cnt].name = "reliable";
 886                         g_value_init(&params[params_cnt].value, G_TYPE_BOOLEAN);
 887                         g_value_set_boolean(&params[params_cnt].value, TRUE);
 888                         ++params_cnt;
 889                 }
 890
 891                 /* Don't use the globally defined stun server (it is used by
 892                  * default in backend-fs2) because it generates srflx local
 893                  * candidates that confuse SfB when they contribute to valid
 894                  * pairs in controlled mode:
 895                  *
 896                  * ms-client-diagnostics: 21
 897                  *   "Call failed to establish due to a media connectivity
 898                  *   failure where one endpoint is of unknown type"
 899                  *
 900                  * These candidates will be discovered anyway during the
 901                  * conncheck as prflx, and they will be accepted and nominated
 902                  * by SfB when having this type. */
 903                 params[params_cnt].name = "stun-ip";
 904                 g_value_init(&params[params_cnt].value, G_TYPE_STRING);
 905                 g_value_set_string(&params[params_cnt].value, NULL);
 906                 ++params_cnt;
 907         } else {
 908                 // TODO: session naming here, Communicator needs audio/video
 909                 transmitter = "rawudp";
 910                 //sessionid = "sipe-voice-rawudp";
 911         }
 912
 913         ensure_codecs_conf();
 914
 915 #ifdef HAVE_XDATA
 916         if (type == SIPE_MEDIA_APPLICATION) {
 917                 purple_media_manager_set_application_data_callbacks(
 918                                 purple_media_manager_get(),
 919                                 media->m, stream->id, stream->call->with,
 920                                 &callbacks, stream->call, NULL);
 921         }
 922 #endif
 923
 924         backend_stream = g_new0(struct sipe_backend_media_stream, 1);
 925
 926         pipe = purple_media_manager_get_pipeline(purple_media_manager_get());
 927         if (pipe) {
 928                 GstBus *bus;
 929
 930                 bus = gst_element_get_bus(pipe);
 931                 backend_stream->gst_bus_cb_id = g_signal_connect(bus, "message",
 932                                 G_CALLBACK(gst_bus_cb), stream);
 933                 gst_object_unref(bus);
 934         }
 935
 936         if (purple_media_add_stream(media->m, stream->id, stream->call->with,
 937                                     sipe_media_to_purple(type),
 938                                     initiator, transmitter, params_cnt,
 939                                     params)) {
 940                 if (!initiator)
 941                         ++media->unconfirmed_streams;
 942         } else {
 943                 sipe_backend_media_stream_free(backend_stream);
 944                 backend_stream = NULL;
 945         }
 946
 947         g_free(params);
 948
 949         return backend_stream;
 950 }
 951
 952 void
 953 sipe_backend_media_stream_end(struct sipe_media_call *media,
 954                               struct sipe_media_stream *stream)
 955 {
 956         purple_media_end(media->backend_private->m, stream->id, NULL);
 957 }
 958
 959 void
 960 sipe_backend_media_add_remote_candidates(struct sipe_media_call *media,
 961                                          struct sipe_media_stream *stream,
 962                                          GList *candidates)
 963 {
 964         GList *udp_candidates = NULL;
 965
 966 #ifndef HAVE_PURPLE_NEW_TCP_ENUMS
 967         /* Keep only UDP candidates in the list to set. */
 968         while (candidates) {
 969                 PurpleMediaCandidate *candidate = candidates->data;
 970                 PurpleMediaNetworkProtocol proto;
 971
 972                 proto = purple_media_candidate_get_protocol(candidate);
 973                 if (proto == PURPLE_MEDIA_NETWORK_PROTOCOL_UDP)
 974                         udp_candidates = g_list_append(udp_candidates, candidate);
 975
 976                 candidates = candidates->next;
 977         }
 978
 979         candidates = udp_candidates;
 980 #endif
 981
 982         purple_media_add_remote_candidates(media->backend_private->m,
 983                                            stream->id, media->with, candidates);
 984
 985         g_list_free(udp_candidates);
 986 }
 987
 988 gboolean sipe_backend_media_is_initiator(struct sipe_media_call *media,
 989                                          struct sipe_media_stream *stream)
 990 {
 991         return purple_media_is_initiator(media->backend_private->m,
 992                                          stream ? stream->id : NULL,
 993                                          stream ? media->with : NULL);
 994 }
 995
 996 gboolean sipe_backend_media_accepted(struct sipe_backend_media *media)
 997 {
 998         return purple_media_accepted(media->m, NULL, NULL);
 999 }
1000
1001 gboolean
1002 sipe_backend_stream_initialized(struct sipe_media_call *media,
1003                                 struct sipe_media_stream *stream)
1004 {
1005         g_return_val_if_fail(media, FALSE);
1006         g_return_val_if_fail(stream, FALSE);
1007
1008         if (purple_media_candidates_prepared(media->backend_private->m,
1009                                              stream->id, media->with)) {
1010                 GList *codecs;
1011                 codecs = purple_media_get_codecs(media->backend_private->m,
1012                                                  stream->id);
1013                 if (codecs) {
1014                         purple_media_codec_list_free(codecs);
1015                         return TRUE;
1016                 }
1017         }
1018         return FALSE;
1019 }
1020
1021 static GList *
1022 duplicate_tcp_candidates(GList *candidates)
1023 {
1024         GList *i;
1025         GList *result = NULL;
1026
1027         for (i = candidates; i; i = i->next) {
1028                 PurpleMediaCandidate *candidate = i->data;
1029                 PurpleMediaNetworkProtocol protocol =
1030                                 purple_media_candidate_get_protocol(candidate);
1031                 guint component_id =
1032                                 purple_media_candidate_get_component_id(candidate);
1033
1034                 if (protocol != PURPLE_MEDIA_NETWORK_PROTOCOL_UDP) {
1035                         PurpleMediaCandidate *c2;
1036
1037                         if (component_id != PURPLE_MEDIA_COMPONENT_RTP) {
1038                                 /* Ignore TCP candidates for other than
1039                                  * the first component. */
1040                                 g_object_unref(candidate);
1041                                 continue;
1042                         }
1043
1044                         c2 = purple_media_candidate_copy(candidate);
1045                         g_object_set(c2,
1046                                      "component-id", PURPLE_MEDIA_COMPONENT_RTCP,
1047                                      NULL);
1048                         result = g_list_append(result, c2);
1049                 }
1050
1051                 result = g_list_append(result, candidate);
1052         }
1053
1054         g_list_free(candidates);
1055
1056         return result;
1057 }
1058
1059 GList *
1060 sipe_backend_media_stream_get_active_local_candidates(struct sipe_media_stream *stream)
1061 {
1062         GList *candidates = purple_media_get_active_local_candidates(
1063                         stream->call->backend_private->m, stream->id,
1064                         stream->call->with);
1065         return duplicate_tcp_candidates(candidates);
1066 }
1067
1068 GList *
1069 sipe_backend_media_stream_get_active_remote_candidates(struct sipe_media_stream *stream)
1070 {
1071         GList *candidates = purple_media_get_active_remote_candidates(
1072                         stream->call->backend_private->m, stream->id,
1073                         stream->call->with);
1074         return duplicate_tcp_candidates(candidates);
1075 }
1076
1077 #ifdef HAVE_SRTP
1078 void
1079 sipe_backend_media_set_encryption_keys(struct sipe_media_call *media,
1080                                        struct sipe_media_stream *stream,
1081                                        const guchar *encryption_key,
1082                                        const guchar *decryption_key)
1083 {
1084         purple_media_set_encryption_parameters(media->backend_private->m,
1085                         stream->id,
1086                         "aes-128-icm",
1087                         "hmac-sha1-80",
1088                         (gchar *)encryption_key, SIPE_SRTP_KEY_LEN);
1089         purple_media_set_decryption_parameters(media->backend_private->m,
1090                         stream->id, media->with,
1091                         "aes-128-icm",
1092                         "hmac-sha1-80",
1093                         (gchar *)decryption_key, SIPE_SRTP_KEY_LEN);
1094 }
1095 #else
1096 void
1097 sipe_backend_media_set_encryption_keys(SIPE_UNUSED_PARAMETER struct sipe_media_call *media,
1098                                        SIPE_UNUSED_PARAMETER struct sipe_media_stream *stream,
1099                                        SIPE_UNUSED_PARAMETER const guchar *encryption_key,
1100                                        SIPE_UNUSED_PARAMETER const guchar *decryption_key)
1101 {}
1102 #endif
1103
1104 #if defined(HAVE_SRTP) && PURPLE_VERSION_CHECK(2,14,0)
1105 void
1106 sipe_backend_media_set_require_encryption(struct sipe_media_call *media,
1107                                           struct sipe_media_stream *stream,
1108                                           const gboolean require_encryption)
1109 {
1110         purple_media_set_require_encryption(media->backend_private->m,
1111                         stream->id, media->with, require_encryption);
1112 }
1113 #else
1114 void
1115 sipe_backend_media_set_require_encryption(SIPE_UNUSED_PARAMETER struct sipe_media_call *media,
1116                                           SIPE_UNUSED_PARAMETER struct sipe_media_stream *stream,
1117                                           SIPE_UNUSED_PARAMETER const gboolean require_encryption)
1118 {}
1119 #endif
1120
1121 void sipe_backend_stream_hold(struct sipe_media_call *media,
1122                               struct sipe_media_stream *stream,
1123                               gboolean local)
1124 {
1125         purple_media_stream_info(media->backend_private->m, PURPLE_MEDIA_INFO_HOLD,
1126                                  stream->id, media->with, local);
1127 }
1128
1129 void sipe_backend_stream_unhold(struct sipe_media_call *media,
1130                                 struct sipe_media_stream *stream,
1131                                 gboolean local)
1132 {
1133         purple_media_stream_info(media->backend_private->m, PURPLE_MEDIA_INFO_UNHOLD,
1134                                  stream->id, media->with, local);
1135 }
1136
1137 gboolean sipe_backend_stream_is_held(struct sipe_media_stream *stream)
1138 {
1139         g_return_val_if_fail(stream, FALSE);
1140
1141         return stream->backend_private->local_on_hold ||
1142                stream->backend_private->remote_on_hold;
1143 }
1144
1145 struct sipe_backend_codec *
1146 sipe_backend_codec_new(int id, const char *name, SipeMediaType type,
1147                        guint clock_rate, guint channels)
1148 {
1149         PurpleMediaCodec *codec;
1150
1151         if (sipe_strcase_equal(name, "X-H264UC")) {
1152                 name = "H264";
1153         }
1154
1155         codec = purple_media_codec_new(id, name, sipe_media_to_purple(type),
1156                                        clock_rate);
1157         g_object_set(codec, "channels", channels, NULL);
1158
1159         return (struct sipe_backend_codec *)codec;
1160 }
1161
1162 void
1163 sipe_backend_codec_free(struct sipe_backend_codec *codec)
1164 {
1165         if (codec)
1166                 g_object_unref(codec);
1167 }
1168
1169 int
1170 sipe_backend_codec_get_id(struct sipe_backend_codec *codec)
1171 {
1172         return purple_media_codec_get_id((PurpleMediaCodec *)codec);
1173 }
1174
1175 gchar *
1176 sipe_backend_codec_get_name(struct sipe_backend_codec *codec)
1177 {
1178         /* Not explicitly documented, but return value must be g_free()'d */
1179         return purple_media_codec_get_encoding_name((PurpleMediaCodec *)codec);
1180 }
1181
1182 guint
1183 sipe_backend_codec_get_clock_rate(struct sipe_backend_codec *codec)
1184 {
1185         return purple_media_codec_get_clock_rate((PurpleMediaCodec *)codec);
1186 }
1187
1188 void
1189 sipe_backend_codec_add_optional_parameter(struct sipe_backend_codec *codec,
1190                                                                                   const gchar *name, const gchar *value)
1191 {
1192         purple_media_codec_add_optional_parameter((PurpleMediaCodec *)codec, name, value);
1193 }
1194
1195 GList *
1196 sipe_backend_codec_get_optional_parameters(struct sipe_backend_codec *codec)
1197 {
1198         return purple_media_codec_get_optional_parameters((PurpleMediaCodec *)codec);
1199 }
1200
1201 gboolean
1202 sipe_backend_set_remote_codecs(struct sipe_media_call *media,
1203                                struct sipe_media_stream *stream,
1204                                GList *codecs)
1205 {
1206         gboolean result;
1207
1208         /* Lync offers multichannel audio as a codec with the same encoding name
1209          * as the mono variant, but a different payload type and an extra
1210          * encoding parameter:
1211          *
1212          *  a=rtpmap:117 G722/8000/2
1213          *  a=rtpmap:9 G722/8000
1214          *
1215          * Since avenc_g722 from gst-libav can encode only one audio channel, ignore
1216          * multichannel codecs we were offered by the remote host.
1217          */
1218         GList *tmp = NULL;
1219         PurpleMediaSessionType type;
1220
1221         for (; codecs; codecs = codecs->next) {
1222                 PurpleMediaCodec *codec = codecs->data;
1223
1224                 g_object_get(codec, "media-type", &type, NULL);
1225
1226                 if (type == PURPLE_MEDIA_AUDIO &&
1227                     purple_media_codec_get_channels(codec) > 1) {
1228                         continue;
1229                 }
1230
1231                 tmp = g_list_append(tmp, codec);
1232         }
1233
1234         result = purple_media_set_remote_codecs(media->backend_private->m,
1235                                                 stream->id, media->with,
1236                                                 tmp);
1237         g_list_free(tmp);
1238
1239         return result;
1240 }
1241
1242 GList*
1243 sipe_backend_get_local_codecs(struct sipe_media_call *media,
1244                               struct sipe_media_stream *stream)
1245 {
1246         GList *codecs = purple_media_get_codecs(media->backend_private->m,
1247                                                 stream->id);
1248         GList *i = codecs;
1249         gboolean is_conference = (g_strstr_len(media->with, strlen(media->with),
1250                                                "app:conf:audio-video:") != NULL);
1251
1252         /*
1253          * Do not announce Theora. Its optional parameters are too long,
1254          * Communicator rejects such SDP message and does not support the codec
1255          * anyway.
1256          *
1257          * For some yet unknown reason, A/V conferencing server does not accept
1258          * voice stream sent by SIPE when SIREN codec is in use. Nevertheless,
1259          * we are able to decode incoming SIREN from server and with MSOC
1260          * client, bidirectional call using the codec works. Until resolved,
1261          * do not try to negotiate SIREN usage when conferencing. PCMA or PCMU
1262          * seems to work properly in this scenario.
1263          */
1264         while (i) {
1265                 PurpleMediaCodec *codec = i->data;
1266                 gchar *encoding_name = purple_media_codec_get_encoding_name(codec);
1267
1268                 if (sipe_strequal(encoding_name,"THEORA") ||
1269                     (is_conference && sipe_strequal(encoding_name,"SIREN"))) {
1270                         GList *tmp;
1271                         g_object_unref(codec);
1272                         tmp = i->next;
1273                         codecs = g_list_delete_link(codecs, i);
1274                         i = tmp;
1275                 } else if (sipe_strequal(encoding_name, "H264")) {
1276                         /*
1277                          * Sanitize H264 codec:
1278                          * - the encoding name must be "X-H264UC"
1279                          * - remove "sprop-parameter-sets" parameter which is
1280                          *   rejected by Lync
1281                          * - add "packetization-mode" parameter if not already
1282                          *   present
1283                          */
1284
1285                         PurpleMediaCodec *new_codec;
1286                         GList *it;
1287
1288                         new_codec = purple_media_codec_new(
1289                                         purple_media_codec_get_id(codec),
1290                                         "X-H264UC",
1291                                         PURPLE_MEDIA_VIDEO,
1292                                         purple_media_codec_get_clock_rate(codec));
1293
1294                         g_object_set(new_codec, "channels",
1295                                         purple_media_codec_get_channels(codec),
1296                                         NULL);
1297
1298                         it = purple_media_codec_get_optional_parameters(codec);
1299
1300                         for (; it; it = g_list_next(it)) {
1301                                 PurpleKeyValuePair *pair = it->data;
1302
1303                                 if (sipe_strequal(pair->key, "sprop-parameter-sets")) {
1304                                         continue;
1305                                 }
1306
1307                                 purple_media_codec_add_optional_parameter(new_codec,
1308                                                 pair->key, pair->value);
1309                         }
1310
1311                         if (!purple_media_codec_get_optional_parameter(new_codec,
1312                                         "packetization-mode", NULL)) {
1313                                 purple_media_codec_add_optional_parameter(new_codec,
1314                                                 "packetization-mode",
1315                                                 "1;mst-mode=NI-TC");
1316                         }
1317
1318                         i->data = new_codec;
1319
1320                         g_object_unref(codec);
1321                 } else
1322                         i = i->next;
1323
1324                 g_free(encoding_name);
1325         }
1326
1327         return codecs;
1328 }
1329
1330 struct sipe_backend_candidate *
1331 sipe_backend_candidate_new(const gchar *foundation,
1332                            SipeComponentType component,
1333                            SipeCandidateType type, SipeNetworkProtocol proto,
1334                            const gchar *ip, guint port,
1335                            const gchar *username,
1336                            const gchar *password)
1337 {
1338         PurpleMediaCandidate *c = purple_media_candidate_new(
1339                 /* Libnice and Farsight rely on non-NULL foundation to
1340                  * distinguish between candidates of a component. When NULL
1341                  * foundation is passed (ie. ICE draft 6 does not use foudation),
1342                  * use username instead. If no foundation is provided, Farsight
1343                  * may signal an active candidate different from the one actually
1344                  * in use. See Farsight's agent_new_selected_pair() in
1345                  * fs-nice-stream-transmitter.h where first candidate in the
1346                  * remote list is always selected when no foundation. */
1347                 foundation ? foundation : username,
1348                 component,
1349                 sipe_candidate_type_to_purple(type),
1350                 sipe_network_protocol_to_purple(proto),
1351                 ip,
1352                 port);
1353         g_object_set(c, "username", username, "password", password, NULL);
1354         return (struct sipe_backend_candidate *)c;
1355 }
1356
1357 void
1358 sipe_backend_candidate_free(struct sipe_backend_candidate *candidate)
1359 {
1360         if (candidate)
1361                 g_object_unref(candidate);
1362 }
1363
1364 gchar *
1365 sipe_backend_candidate_get_username(struct sipe_backend_candidate *candidate)
1366 {
1367         /* Not explicitly documented, but return value must be g_free()'d */
1368         return purple_media_candidate_get_username((PurpleMediaCandidate*)candidate);
1369 }
1370
1371 gchar *
1372 sipe_backend_candidate_get_password(struct sipe_backend_candidate *candidate)
1373 {
1374         /* Not explicitly documented, but return value must be g_free()'d */
1375         return purple_media_candidate_get_password((PurpleMediaCandidate*)candidate);
1376 }
1377
1378 gchar *
1379 sipe_backend_candidate_get_foundation(struct sipe_backend_candidate *candidate)
1380 {
1381         /* Not explicitly documented, but return value must be g_free()'d */
1382         return purple_media_candidate_get_foundation((PurpleMediaCandidate*)candidate);
1383 }
1384
1385 gchar *
1386 sipe_backend_candidate_get_ip(struct sipe_backend_candidate *candidate)
1387 {
1388         /* Not explicitly documented, but return value must be g_free()'d */
1389         return purple_media_candidate_get_ip((PurpleMediaCandidate*)candidate);
1390 }
1391
1392 guint
1393 sipe_backend_candidate_get_port(struct sipe_backend_candidate *candidate)
1394 {
1395         return purple_media_candidate_get_port((PurpleMediaCandidate*)candidate);
1396 }
1397
1398 gchar *
1399 sipe_backend_candidate_get_base_ip(struct sipe_backend_candidate *candidate)
1400 {
1401         /* Not explicitly documented, but return value must be g_free()'d */
1402         return purple_media_candidate_get_base_ip((PurpleMediaCandidate*)candidate);
1403 }
1404
1405 guint
1406 sipe_backend_candidate_get_base_port(struct sipe_backend_candidate *candidate)
1407 {
1408         return purple_media_candidate_get_base_port((PurpleMediaCandidate*)candidate);
1409 }
1410
1411 guint32
1412 sipe_backend_candidate_get_priority(struct sipe_backend_candidate *candidate)
1413 {
1414         return purple_media_candidate_get_priority((PurpleMediaCandidate*)candidate);
1415 }
1416
1417 void
1418 sipe_backend_candidate_set_priority(struct sipe_backend_candidate *candidate, guint32 priority)
1419 {
1420         g_object_set(candidate, "priority", priority, NULL);
1421 }
1422
1423 SipeComponentType
1424 sipe_backend_candidate_get_component_type(struct sipe_backend_candidate *candidate)
1425 {
1426         return purple_media_candidate_get_component_id((PurpleMediaCandidate*)candidate);
1427 }
1428
1429 SipeCandidateType
1430 sipe_backend_candidate_get_type(struct sipe_backend_candidate *candidate)
1431 {
1432         PurpleMediaCandidateType type =
1433                 purple_media_candidate_get_candidate_type((PurpleMediaCandidate*)candidate);
1434         return purple_candidate_type_to_sipe(type);
1435 }
1436
1437 SipeNetworkProtocol
1438 sipe_backend_candidate_get_protocol(struct sipe_backend_candidate *candidate)
1439 {
1440         PurpleMediaNetworkProtocol proto =
1441                 purple_media_candidate_get_protocol((PurpleMediaCandidate*)candidate);
1442         return purple_network_protocol_to_sipe(proto);
1443 }
1444
1445 /*
1446  * libnice can return a candidate list with duplicates. It is currently
1447  * unknown if this is a bug in libnice or a configuration error in Skype
1448  * for Business setups.
1449  *
1450  * While this is not a bug in SIPE, by removing these duplicates we make
1451  * sure that SIPE doesn't generate incorrect SDP messages.
1452  */
1453 static GList *
1454 filter_duplicate_candidates(GList *candidates)
1455 {
1456         GHashTable *seen   = g_hash_table_new_full(g_str_hash, g_str_equal,
1457                                                    g_free, NULL);
1458         GList      *result = NULL;
1459         GList      *it;
1460
1461         for (it = candidates; it; it = it->next) {
1462                 PurpleMediaCandidate *c = it->data;
1463                 gchar *foundation = purple_media_candidate_get_foundation(c);
1464                 gchar *ip         = purple_media_candidate_get_ip(c);
1465                 gchar *base_ip    = purple_media_candidate_get_base_ip(c);
1466                 gchar *id = g_strdup_printf("%s %d %d %d %s %d %d %s %d",
1467                         foundation ? foundation : "-",
1468                         purple_media_candidate_get_component_id(c),
1469                         purple_media_candidate_get_protocol(c),
1470                         purple_media_candidate_get_priority(c),
1471                         ip ? ip : "-",
1472                         purple_media_candidate_get_port(c),
1473                         purple_media_candidate_get_candidate_type(c),
1474                         base_ip ? base_ip : "-",
1475                         purple_media_candidate_get_base_port(c)
1476                 );
1477
1478                 g_free(base_ip);
1479                 g_free(ip);
1480                 g_free(foundation);
1481
1482                 if (g_hash_table_lookup(seen, id)) {
1483                         SIPE_DEBUG_INFO("filter_duplicate_candidates: dropping '%s'",
1484                                         id);
1485                         g_free(id);
1486                         g_object_unref(c);
1487                 } else {
1488                         g_hash_table_insert(seen, id, GUINT_TO_POINTER(TRUE));
1489                         result = g_list_append(result, c);
1490                 }
1491         }
1492
1493         g_hash_table_destroy(seen);
1494         g_list_free(candidates);
1495
1496         return result;
1497 }
1498
1499 static void
1500 remove_lone_candidate_cb(SIPE_UNUSED_PARAMETER gpointer key,
1501                          gpointer value,
1502                          gpointer user_data)
1503 {
1504         GList  *entry = value;
1505         GList **candidates = user_data;
1506
1507         g_object_unref(entry->data);
1508         *candidates = g_list_delete_link(*candidates, entry);
1509 }
1510
1511 static GList *
1512 ensure_candidate_pairs(GList *candidates)
1513 {
1514         GHashTable *lone_cand_links;
1515         GList      *i;
1516
1517         lone_cand_links = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL);
1518
1519         for (i = candidates; i; i = i->next) {
1520                 PurpleMediaCandidate *c = i->data;
1521                 gchar *foundation = purple_media_candidate_get_foundation(c);
1522
1523                 if (g_hash_table_lookup(lone_cand_links, foundation)) {
1524                         g_hash_table_remove(lone_cand_links, foundation);
1525                         g_free(foundation);
1526                 } else {
1527                         g_hash_table_insert(lone_cand_links, foundation, i);
1528                 }
1529         }
1530
1531         g_hash_table_foreach(lone_cand_links, remove_lone_candidate_cb, &candidates);
1532         g_hash_table_destroy(lone_cand_links);
1533
1534         return candidates;
1535 }
1536
1537 GList *
1538 sipe_backend_get_local_candidates(struct sipe_media_call *media,
1539                                   struct sipe_media_stream *stream)
1540 {
1541         GList *candidates =
1542                         purple_media_get_local_candidates(media->backend_private->m,
1543                                                           stream->id,
1544                                                           media->with);
1545         candidates = filter_duplicate_candidates(candidates);
1546         candidates = duplicate_tcp_candidates(candidates);
1547
1548         /*
1549          * Sometimes purple will not return complete list of candidates, even
1550          * after "candidates-prepared" signal is emitted. This is a feature of
1551          * libnice, namely affecting candidates discovered via UPnP. Nice does
1552          * not wait until discovery is finished and can signal end of candidate
1553          * gathering before all responses from UPnP enabled gateways are received.
1554          *
1555          * Remove any incomplete RTP+RTCP candidate pairs from the list.
1556          */
1557         candidates = ensure_candidate_pairs(candidates);
1558         return candidates;
1559 }
1560
1561 void
1562 sipe_backend_media_accept(struct sipe_backend_media *media, gboolean local)
1563 {
1564         if (media)
1565                 purple_media_stream_info(media->m, PURPLE_MEDIA_INFO_ACCEPT,
1566                                          NULL, NULL, local);
1567 }
1568
1569 void
1570 sipe_backend_media_hangup(struct sipe_backend_media *media, gboolean local)
1571 {
1572         if (media)
1573                 purple_media_stream_info(media->m, PURPLE_MEDIA_INFO_HANGUP,
1574                                          NULL, NULL, local);
1575 }
1576
1577 void
1578 sipe_backend_media_reject(struct sipe_backend_media *media, gboolean local)
1579 {
1580         if (media)
1581                 purple_media_stream_info(media->m, PURPLE_MEDIA_INFO_REJECT,
1582                                          NULL, NULL, local);
1583 }
1584
1585 static PurpleMediaSessionType sipe_media_to_purple(SipeMediaType type)
1586 {
1587         switch (type) {
1588                 case SIPE_MEDIA_AUDIO: return PURPLE_MEDIA_AUDIO;
1589                 case SIPE_MEDIA_VIDEO: return PURPLE_MEDIA_VIDEO;
1590 #ifdef HAVE_XDATA
1591                 case SIPE_MEDIA_APPLICATION: return PURPLE_MEDIA_APPLICATION;
1592 #endif
1593                 default:               return PURPLE_MEDIA_NONE;
1594         }
1595 }
1596
1597 static PurpleMediaCandidateType
1598 sipe_candidate_type_to_purple(SipeCandidateType type)
1599 {
1600         switch (type) {
1601                 case SIPE_CANDIDATE_TYPE_HOST:  return PURPLE_MEDIA_CANDIDATE_TYPE_HOST;
1602                 case SIPE_CANDIDATE_TYPE_RELAY: return PURPLE_MEDIA_CANDIDATE_TYPE_RELAY;
1603                 case SIPE_CANDIDATE_TYPE_SRFLX: return PURPLE_MEDIA_CANDIDATE_TYPE_SRFLX;
1604                 case SIPE_CANDIDATE_TYPE_PRFLX: return PURPLE_MEDIA_CANDIDATE_TYPE_PRFLX;
1605                 default:                        return PURPLE_MEDIA_CANDIDATE_TYPE_HOST;
1606         }
1607 }
1608
1609 static SipeCandidateType
1610 purple_candidate_type_to_sipe(PurpleMediaCandidateType type)
1611 {
1612         switch (type) {
1613                 case PURPLE_MEDIA_CANDIDATE_TYPE_HOST:  return SIPE_CANDIDATE_TYPE_HOST;
1614                 case PURPLE_MEDIA_CANDIDATE_TYPE_RELAY: return SIPE_CANDIDATE_TYPE_RELAY;
1615                 case PURPLE_MEDIA_CANDIDATE_TYPE_SRFLX: return SIPE_CANDIDATE_TYPE_SRFLX;
1616                 case PURPLE_MEDIA_CANDIDATE_TYPE_PRFLX: return SIPE_CANDIDATE_TYPE_PRFLX;
1617                 default:                                return SIPE_CANDIDATE_TYPE_HOST;
1618         }
1619 }
1620
1621 static PurpleMediaNetworkProtocol
1622 sipe_network_protocol_to_purple(SipeNetworkProtocol proto)
1623 {
1624         switch (proto) {
1625 #ifdef HAVE_PURPLE_NEW_TCP_ENUMS
1626                 case SIPE_NETWORK_PROTOCOL_TCP_ACTIVE:
1627                         return PURPLE_MEDIA_NETWORK_PROTOCOL_TCP_ACTIVE;
1628                 case SIPE_NETWORK_PROTOCOL_TCP_PASSIVE:
1629                         return PURPLE_MEDIA_NETWORK_PROTOCOL_TCP_PASSIVE;
1630                 case SIPE_NETWORK_PROTOCOL_TCP_SO:
1631                         return PURPLE_MEDIA_NETWORK_PROTOCOL_TCP_SO;
1632 #else
1633                 case SIPE_NETWORK_PROTOCOL_TCP_ACTIVE:
1634                 case SIPE_NETWORK_PROTOCOL_TCP_PASSIVE:
1635                 case SIPE_NETWORK_PROTOCOL_TCP_SO:
1636                         return PURPLE_MEDIA_NETWORK_PROTOCOL_TCP;
1637 #endif
1638                 default:
1639                 case SIPE_NETWORK_PROTOCOL_UDP:
1640                         return PURPLE_MEDIA_NETWORK_PROTOCOL_UDP;
1641         }
1642 }
1643
1644 static SipeNetworkProtocol
1645 purple_network_protocol_to_sipe(PurpleMediaNetworkProtocol proto)
1646 {
1647         switch (proto) {
1648 #ifdef HAVE_PURPLE_NEW_TCP_ENUMS
1649                 case PURPLE_MEDIA_NETWORK_PROTOCOL_TCP_ACTIVE:
1650                         return SIPE_NETWORK_PROTOCOL_TCP_ACTIVE;
1651                 case PURPLE_MEDIA_NETWORK_PROTOCOL_TCP_PASSIVE:
1652                         return SIPE_NETWORK_PROTOCOL_TCP_PASSIVE;
1653                 case PURPLE_MEDIA_NETWORK_PROTOCOL_TCP_SO:
1654                         return SIPE_NETWORK_PROTOCOL_TCP_SO;
1655 #else
1656                 case PURPLE_MEDIA_NETWORK_PROTOCOL_TCP:
1657                         return SIPE_NETWORK_PROTOCOL_TCP_ACTIVE;
1658 #endif
1659                 default:
1660                 case PURPLE_MEDIA_NETWORK_PROTOCOL_UDP:
1661                         return SIPE_NETWORK_PROTOCOL_UDP;
1662         }
1663 }
1664
1665 #ifdef HAVE_SRTP
1666 SipeEncryptionPolicy
1667 sipe_backend_media_get_encryption_policy(struct sipe_core_public *sipe_public)
1668 {
1669         PurpleAccount *account = sipe_public->backend_private->account;
1670
1671         const char *policy =
1672                         purple_account_get_string(account, "encryption-policy",
1673                                                   "obey-server");
1674
1675         if (sipe_strequal(policy, "disabled")) {
1676                 return SIPE_ENCRYPTION_POLICY_REJECTED;
1677         } else if (sipe_strequal(policy, "optional")) {
1678                 return SIPE_ENCRYPTION_POLICY_OPTIONAL;
1679         } else if (sipe_strequal(policy, "required")) {
1680                 return SIPE_ENCRYPTION_POLICY_REQUIRED;
1681         } else {
1682                 return SIPE_ENCRYPTION_POLICY_OBEY_SERVER;
1683         }
1684 }
1685 #else
1686 SipeEncryptionPolicy
1687 sipe_backend_media_get_encryption_policy(SIPE_UNUSED_PARAMETER struct sipe_core_public *sipe_public)
1688 {
1689         return SIPE_ENCRYPTION_POLICY_REJECTED;
1690 }
1691 #endif
1692
1693 /*
1694   Local Variables:
1695   mode: c
1696   c-file-style: "bsd"
1697   indent-tabs-mode: t
1698   tab-width: 8
1699   End:
1700 */