Fix shutdown crash caused by modules being left open.
[asterisk/asterisk.git] / bridges / bridge_native_rtp.c
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2013, Digium, Inc.
5  *
6  * Joshua Colp <jcolp@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 /*! \file
20  *
21  * \brief Native RTP bridging technology module
22  *
23  * \author Joshua Colp <jcolp@digium.com>
24  *
25  * \ingroup bridges
26  */
27
28 /*** MODULEINFO
29         <support_level>core</support_level>
30  ***/
31
32 #include "asterisk.h"
33
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <sys/types.h>
38 #include <sys/stat.h>
39
40 #include "asterisk/module.h"
41 #include "asterisk/channel.h"
42 #include "asterisk/bridge.h"
43 #include "asterisk/bridge_technology.h"
44 #include "asterisk/frame.h"
45 #include "asterisk/rtp_engine.h"
46
47 /*! \brief Internal structure which contains information about bridged RTP channels */
48 struct native_rtp_bridge_data {
49         /*! \brief Framehook used to intercept certain control frames */
50         int id;
51         /*! \brief Set when this framehook has been detached */
52         unsigned int detached;
53 };
54
55 /*! \brief Internal helper function which gets all RTP information (glue and instances) relating to the given channels */
56 static enum ast_rtp_glue_result native_rtp_bridge_get(struct ast_channel *c0, struct ast_channel *c1, struct ast_rtp_glue **glue0,
57         struct ast_rtp_glue **glue1, struct ast_rtp_instance **instance0, struct ast_rtp_instance **instance1,
58         struct ast_rtp_instance **vinstance0, struct ast_rtp_instance **vinstance1)
59 {
60         enum ast_rtp_glue_result audio_glue0_res;
61         enum ast_rtp_glue_result video_glue0_res;
62         enum ast_rtp_glue_result audio_glue1_res;
63         enum ast_rtp_glue_result video_glue1_res;
64
65         if (!(*glue0 = ast_rtp_instance_get_glue(ast_channel_tech(c0)->type)) ||
66                 !(*glue1 = ast_rtp_instance_get_glue(ast_channel_tech(c1)->type))) {
67                 return AST_RTP_GLUE_RESULT_FORBID;
68         }
69
70         audio_glue0_res = (*glue0)->get_rtp_info(c0, instance0);
71         video_glue0_res = (*glue0)->get_vrtp_info ? (*glue0)->get_vrtp_info(c0, vinstance0) : AST_RTP_GLUE_RESULT_FORBID;
72
73         audio_glue1_res = (*glue1)->get_rtp_info(c1, instance1);
74         video_glue1_res = (*glue1)->get_vrtp_info ? (*glue1)->get_vrtp_info(c1, vinstance1) : AST_RTP_GLUE_RESULT_FORBID;
75
76         /* Apply any limitations on direct media bridging that may be present */
77         if (audio_glue0_res == audio_glue1_res && audio_glue1_res == AST_RTP_GLUE_RESULT_REMOTE) {
78                 if ((*glue0)->allow_rtp_remote && !((*glue0)->allow_rtp_remote(c0, *instance1))) {
79                         /* If the allow_rtp_remote indicates that remote isn't allowed, revert to local bridge */
80                         audio_glue0_res = audio_glue1_res = AST_RTP_GLUE_RESULT_LOCAL;
81                 } else if ((*glue1)->allow_rtp_remote && !((*glue1)->allow_rtp_remote(c1, *instance0))) {
82                         audio_glue0_res = audio_glue1_res = AST_RTP_GLUE_RESULT_LOCAL;
83                 }
84         }
85         if (video_glue0_res == video_glue1_res && video_glue1_res == AST_RTP_GLUE_RESULT_REMOTE) {
86                 if ((*glue0)->allow_vrtp_remote && !((*glue0)->allow_vrtp_remote(c0, *instance1))) {
87                         /* if the allow_vrtp_remote indicates that remote isn't allowed, revert to local bridge */
88                         video_glue0_res = video_glue1_res = AST_RTP_GLUE_RESULT_LOCAL;
89                 } else if ((*glue1)->allow_vrtp_remote && !((*glue1)->allow_vrtp_remote(c1, *instance0))) {
90                         video_glue0_res = video_glue1_res = AST_RTP_GLUE_RESULT_LOCAL;
91                 }
92         }
93
94         /* If we are carrying video, and both sides are not going to remotely bridge... fail the native bridge */
95         if (video_glue0_res != AST_RTP_GLUE_RESULT_FORBID
96                 && (audio_glue0_res != AST_RTP_GLUE_RESULT_REMOTE
97                         || video_glue0_res != AST_RTP_GLUE_RESULT_REMOTE)) {
98                 audio_glue0_res = AST_RTP_GLUE_RESULT_FORBID;
99         }
100         if (video_glue1_res != AST_RTP_GLUE_RESULT_FORBID
101                 && (audio_glue1_res != AST_RTP_GLUE_RESULT_REMOTE
102                         || video_glue1_res != AST_RTP_GLUE_RESULT_REMOTE)) {
103                 audio_glue1_res = AST_RTP_GLUE_RESULT_FORBID;
104         }
105
106         /* The order of preference is: forbid, local, and remote. */
107         if (audio_glue0_res == AST_RTP_GLUE_RESULT_FORBID ||
108                 audio_glue1_res == AST_RTP_GLUE_RESULT_FORBID) {
109                 /* If any sort of bridge is forbidden just completely bail out and go back to generic bridging */
110                 return AST_RTP_GLUE_RESULT_FORBID;
111         } else if (audio_glue0_res == AST_RTP_GLUE_RESULT_LOCAL ||
112                 audio_glue1_res == AST_RTP_GLUE_RESULT_LOCAL) {
113                 return AST_RTP_GLUE_RESULT_LOCAL;
114         } else {
115                 return AST_RTP_GLUE_RESULT_REMOTE;
116         }
117 }
118
119 /*!
120  * \internal
121  * \brief Start native RTP bridging of two channels
122  *
123  * \param bridge The bridge that had native RTP bridging happening on it
124  * \param target If remote RTP bridging, the channel that is unheld.
125  *
126  * \note Bridge must be locked when calling this function.
127  */
128 static void native_rtp_bridge_start(struct ast_bridge *bridge, struct ast_channel *target)
129 {
130         struct ast_bridge_channel *bc0 = AST_LIST_FIRST(&bridge->channels);
131         struct ast_bridge_channel *bc1 = AST_LIST_LAST(&bridge->channels);
132         enum ast_rtp_glue_result native_type;
133         struct ast_rtp_glue *glue0, *glue1;
134         RAII_VAR(struct ast_rtp_instance *, instance0, NULL, ao2_cleanup);
135         RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ao2_cleanup);
136         RAII_VAR(struct ast_rtp_instance *, vinstance0, NULL, ao2_cleanup);
137         RAII_VAR(struct ast_rtp_instance *, vinstance1, NULL, ao2_cleanup);
138         RAII_VAR(struct ast_rtp_instance *, tinstance0, NULL, ao2_cleanup);
139         RAII_VAR(struct ast_rtp_instance *, tinstance1, NULL, ao2_cleanup);
140         RAII_VAR(struct ast_format_cap *, cap0, ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT), ao2_cleanup);
141         RAII_VAR(struct ast_format_cap *, cap1, ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT), ao2_cleanup);
142
143         if (bc0 == bc1) {
144                 return;
145         }
146
147         ast_channel_lock_both(bc0->chan, bc1->chan);
148         native_type = native_rtp_bridge_get(bc0->chan, bc1->chan, &glue0, &glue1, &instance0, &instance1, &vinstance0, &vinstance1);
149
150         switch (native_type) {
151         case AST_RTP_GLUE_RESULT_LOCAL:
152                 if (ast_rtp_instance_get_engine(instance0)->local_bridge) {
153                         ast_rtp_instance_get_engine(instance0)->local_bridge(instance0, instance1);
154                 }
155                 if (ast_rtp_instance_get_engine(instance1)->local_bridge) {
156                         ast_rtp_instance_get_engine(instance1)->local_bridge(instance1, instance0);
157                 }
158                 ast_rtp_instance_set_bridged(instance0, instance1);
159                 ast_rtp_instance_set_bridged(instance1, instance0);
160                 ast_verb(4, "Locally RTP bridged '%s' and '%s' in stack\n",
161                         ast_channel_name(bc0->chan), ast_channel_name(bc1->chan));
162                 break;
163
164         case AST_RTP_GLUE_RESULT_REMOTE:
165                 if (glue0->get_codec) {
166                         glue0->get_codec(bc0->chan, cap0);
167                 }
168                 if (glue1->get_codec) {
169                         glue1->get_codec(bc1->chan, cap1);
170                 }
171
172                 /* If we have a target, it's the channel that received the UNHOLD or UPDATE_RTP_PEER frame and was told to resume */
173                 if (!target) {
174                         glue0->update_peer(bc0->chan, instance1, vinstance1, tinstance1, cap1, 0);
175                         glue1->update_peer(bc1->chan, instance0, vinstance0, tinstance0, cap0, 0);
176                         ast_verb(4, "Remotely bridged '%s' and '%s' - media will flow directly between them\n",
177                                 ast_channel_name(bc0->chan), ast_channel_name(bc1->chan));
178                 } else {
179                         /*
180                          * If a target was provided, it is the recipient of an unhold or an update and needs to have
181                          * its media redirected to fit the current remote bridging needs. The other channel is either
182                          * already set up to handle the new media path or will have its own set of updates independent
183                          * of this pass.
184                          */
185                         if (bc0->chan == target) {
186                                 glue0->update_peer(bc0->chan, instance1, vinstance1, tinstance1, cap1, 0);
187                         } else {
188                                 glue1->update_peer(bc1->chan, instance0, vinstance0, tinstance0, cap0, 0);
189                         }
190                 }
191                 break;
192         case AST_RTP_GLUE_RESULT_FORBID:
193                 break;
194         }
195
196         ast_channel_unlock(bc0->chan);
197         ast_channel_unlock(bc1->chan);
198 }
199
200 static void native_rtp_bridge_stop(struct ast_bridge *bridge, struct ast_channel *target)
201 {
202         struct ast_bridge_channel *bc0 = AST_LIST_FIRST(&bridge->channels);
203         struct ast_bridge_channel *bc1 = AST_LIST_LAST(&bridge->channels);
204         enum ast_rtp_glue_result native_type;
205         struct ast_rtp_glue *glue0, *glue1 = NULL;
206         RAII_VAR(struct ast_rtp_instance *, instance0, NULL, ao2_cleanup);
207         RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ao2_cleanup);
208         RAII_VAR(struct ast_rtp_instance *, vinstance0, NULL, ao2_cleanup);
209         RAII_VAR(struct ast_rtp_instance *, vinstance1, NULL, ao2_cleanup);
210
211         if (bc0 == bc1) {
212                 return;
213         }
214
215         ast_channel_lock_both(bc0->chan, bc1->chan);
216         native_type = native_rtp_bridge_get(bc0->chan, bc1->chan, &glue0, &glue1, &instance0, &instance1, &vinstance0, &vinstance1);
217
218         switch (native_type) {
219         case AST_RTP_GLUE_RESULT_LOCAL:
220                 if (ast_rtp_instance_get_engine(instance0)->local_bridge) {
221                         ast_rtp_instance_get_engine(instance0)->local_bridge(instance0, NULL);
222                 }
223                 if (instance1 && ast_rtp_instance_get_engine(instance1)->local_bridge) {
224                         ast_rtp_instance_get_engine(instance1)->local_bridge(instance1, NULL);
225                 }
226                 ast_rtp_instance_set_bridged(instance0, NULL);
227                 if (instance1) {
228                         ast_rtp_instance_set_bridged(instance1, NULL);
229                 }
230                 break;
231         case AST_RTP_GLUE_RESULT_REMOTE:
232                 if (target) {
233                         /*
234                          * If a target was provided, it is being put on hold and should expect to
235                          * receive media from Asterisk instead of what it was previously connected to.
236                          */
237                         if (bc0->chan == target) {
238                                 glue0->update_peer(bc0->chan, NULL, NULL, NULL, NULL, 0);
239                         } else {
240                                 glue1->update_peer(bc1->chan, NULL, NULL, NULL, NULL, 0);
241                         }
242                 }
243                 break;
244         case AST_RTP_GLUE_RESULT_FORBID:
245                 break;
246         }
247
248         if (!target && native_type != AST_RTP_GLUE_RESULT_FORBID) {
249                 glue0->update_peer(bc0->chan, NULL, NULL, NULL, NULL, 0);
250                 glue1->update_peer(bc1->chan, NULL, NULL, NULL, NULL, 0);
251         }
252
253         ast_debug(2, "Discontinued RTP bridging of '%s' and '%s' - media will flow through Asterisk core\n",
254                 ast_channel_name(bc0->chan), ast_channel_name(bc1->chan));
255
256         ast_channel_unlock(bc0->chan);
257         ast_channel_unlock(bc1->chan);
258 }
259
260 /*! \brief Frame hook that is called to intercept hold/unhold */
261 static struct ast_frame *native_rtp_framehook(struct ast_channel *chan, struct ast_frame *f, enum ast_framehook_event event, void *data)
262 {
263         RAII_VAR(struct ast_bridge *, bridge, NULL, ao2_cleanup);
264         struct native_rtp_bridge_data *native_data = data;
265
266         if (!f || (event != AST_FRAMEHOOK_EVENT_WRITE)) {
267                 return f;
268         }
269
270         bridge = ast_channel_get_bridge(chan);
271
272         if (bridge) {
273                 /* native_rtp_bridge_start/stop are not being called from bridging
274                    core so we need to lock the bridge prior to calling these functions
275                    Unfortunately that means unlocking the channel, but as it
276                    should not be modified this should be okay... hopefully...
277                    unless this channel is being moved around right now and is in
278                    the process of having this framehook removed (which is fine). To
279                    ensure we then don't stop or start when we shouldn't we consult
280                    the data provided. If this framehook has been detached then the
281                    detached variable will be set. This is safe to check as it is only
282                    manipulated with the bridge lock held. */
283                 ast_channel_unlock(chan);
284                 ast_bridge_lock(bridge);
285                 if (!native_data->detached) {
286                         if (f->subclass.integer == AST_CONTROL_HOLD) {
287                                 native_rtp_bridge_stop(bridge, chan);
288                         } else if ((f->subclass.integer == AST_CONTROL_UNHOLD) ||
289                                 (f->subclass.integer == AST_CONTROL_UPDATE_RTP_PEER)) {
290                                 native_rtp_bridge_start(bridge, chan);
291                         }
292                 }
293                 ast_bridge_unlock(bridge);
294                 ast_channel_lock(chan);
295
296         }
297
298         return f;
299 }
300
301 /*! \brief Callback function which informs upstream if we are consuming a frame of a specific type */
302 static int native_rtp_framehook_consume(void *data, enum ast_frame_type type)
303 {
304         return (type == AST_FRAME_CONTROL ? 1 : 0);
305 }
306
307 /*! \brief Internal helper function which checks whether the channels are compatible with our native bridging */
308 static int native_rtp_bridge_capable(struct ast_channel *chan)
309 {
310         return !ast_channel_has_hook_requiring_audio(chan);
311 }
312
313 static int native_rtp_bridge_compatible(struct ast_bridge *bridge)
314 {
315         struct ast_bridge_channel *bc0 = AST_LIST_FIRST(&bridge->channels);
316         struct ast_bridge_channel *bc1 = AST_LIST_LAST(&bridge->channels);
317         enum ast_rtp_glue_result native_type;
318         struct ast_rtp_glue *glue0, *glue1;
319         RAII_VAR(struct ast_rtp_instance *, instance0, NULL, ao2_cleanup);
320         RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ao2_cleanup);
321         RAII_VAR(struct ast_rtp_instance *, vinstance0, NULL, ao2_cleanup);
322         RAII_VAR(struct ast_rtp_instance *, vinstance1, NULL, ao2_cleanup);
323         RAII_VAR(struct ast_format_cap *, cap0, NULL, ao2_cleanup);
324         RAII_VAR(struct ast_format_cap *, cap1, NULL, ao2_cleanup);
325         int read_ptime0, read_ptime1, write_ptime0, write_ptime1;
326
327         /* We require two channels before even considering native bridging */
328         if (bridge->num_channels != 2) {
329                 ast_debug(1, "Bridge '%s' can not use native RTP bridge as two channels are required\n",
330                         bridge->uniqueid);
331                 return 0;
332         }
333
334         if (!native_rtp_bridge_capable(bc0->chan)) {
335                 ast_debug(1, "Bridge '%s' can not use native RTP bridge as channel '%s' has features which prevent it\n",
336                         bridge->uniqueid, ast_channel_name(bc0->chan));
337                 return 0;
338         }
339
340         if (!native_rtp_bridge_capable(bc1->chan)) {
341                 ast_debug(1, "Bridge '%s' can not use native RTP bridge as channel '%s' has features which prevent it\n",
342                         bridge->uniqueid, ast_channel_name(bc1->chan));
343                 return 0;
344         }
345
346         if ((native_type = native_rtp_bridge_get(bc0->chan, bc1->chan, &glue0, &glue1, &instance0, &instance1, &vinstance0, &vinstance1))
347                 == AST_RTP_GLUE_RESULT_FORBID) {
348                 ast_debug(1, "Bridge '%s' can not use native RTP bridge as it was forbidden while getting details\n",
349                         bridge->uniqueid);
350                 return 0;
351         }
352
353         if (ao2_container_count(bc0->features->dtmf_hooks) && ast_rtp_instance_dtmf_mode_get(instance0)) {
354                 ast_debug(1, "Bridge '%s' can not use native RTP bridge as channel '%s' has DTMF hooks\n",
355                         bridge->uniqueid, ast_channel_name(bc0->chan));
356                 return 0;
357         }
358
359         if (ao2_container_count(bc1->features->dtmf_hooks) && ast_rtp_instance_dtmf_mode_get(instance1)) {
360                 ast_debug(1, "Bridge '%s' can not use native RTP bridge as channel '%s' has DTMF hooks\n",
361                         bridge->uniqueid, ast_channel_name(bc1->chan));
362                 return 0;
363         }
364
365         if ((native_type == AST_RTP_GLUE_RESULT_LOCAL) && ((ast_rtp_instance_get_engine(instance0)->local_bridge !=
366                 ast_rtp_instance_get_engine(instance1)->local_bridge) ||
367                 (ast_rtp_instance_get_engine(instance0)->dtmf_compatible &&
368                         !ast_rtp_instance_get_engine(instance0)->dtmf_compatible(bc0->chan, instance0, bc1->chan, instance1)))) {
369                 ast_debug(1, "Bridge '%s' can not use local native RTP bridge as local bridge or DTMF is not compatible\n",
370                         bridge->uniqueid);
371                 return 0;
372         }
373
374         cap0 = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
375         cap1 = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
376         if (!cap0 || !cap1) {
377                 return 0;
378         }
379
380         /* Make sure that codecs match */
381         if (glue0->get_codec) {
382                 glue0->get_codec(bc0->chan, cap0);
383         }
384         if (glue1->get_codec) {
385                 glue1->get_codec(bc1->chan, cap1);
386         }
387         if (ast_format_cap_count(cap0) != 0 && ast_format_cap_count(cap1) != 0 && !ast_format_cap_iscompatible(cap0, cap1)) {
388                 struct ast_str *codec_buf0 = ast_str_alloca(AST_FORMAT_CAP_NAMES_LEN);
389                 struct ast_str *codec_buf1 = ast_str_alloca(AST_FORMAT_CAP_NAMES_LEN);
390                 ast_debug(1, "Channel codec0 = %s is not codec1 = %s, cannot native bridge in RTP.\n",
391                         ast_format_cap_get_names(cap0, &codec_buf0), ast_format_cap_get_names(cap1, &codec_buf1));
392                 return 0;
393         }
394
395         read_ptime0 = ast_format_cap_get_format_framing(cap0, ast_channel_rawreadformat(bc0->chan));
396         read_ptime1 = ast_format_cap_get_format_framing(cap1, ast_channel_rawreadformat(bc1->chan));
397         write_ptime0 = ast_format_cap_get_format_framing(cap0, ast_channel_rawwriteformat(bc0->chan));
398         write_ptime1 = ast_format_cap_get_format_framing(cap1, ast_channel_rawwriteformat(bc1->chan));
399
400         if (read_ptime0 != write_ptime1 || read_ptime1 != write_ptime0) {
401                 ast_debug(1, "Packetization differs between RTP streams (%d != %d or %d != %d). Cannot native bridge in RTP\n",
402                                 read_ptime0, write_ptime1, read_ptime1, write_ptime0);
403                 return 0;
404         }
405
406         return 1;
407 }
408
409 /*! \brief Helper function which adds frame hook to bridge channel */
410 static int native_rtp_bridge_framehook_attach(struct ast_bridge_channel *bridge_channel)
411 {
412         struct native_rtp_bridge_data *data = ao2_alloc(sizeof(*data), NULL);
413         static struct ast_framehook_interface hook = {
414                 .version = AST_FRAMEHOOK_INTERFACE_VERSION,
415                 .event_cb = native_rtp_framehook,
416                 .destroy_cb = __ao2_cleanup,
417                 .consume_cb = native_rtp_framehook_consume,
418                 .disable_inheritance = 1,
419         };
420
421         if (!data) {
422                 return -1;
423         }
424
425         ast_channel_lock(bridge_channel->chan);
426         hook.data = ao2_bump(data);
427         data->id = ast_framehook_attach(bridge_channel->chan, &hook);
428         ast_channel_unlock(bridge_channel->chan);
429         if (data->id < 0) {
430                 /* We need to drop both the reference we hold, and the one the framehook would hold */
431                 ao2_ref(data, -2);
432                 return -1;
433         }
434
435         bridge_channel->tech_pvt = data;
436
437         return 0;
438 }
439
440 /*! \brief Helper function which removes frame hook from bridge channel */
441 static void native_rtp_bridge_framehook_detach(struct ast_bridge_channel *bridge_channel)
442 {
443         RAII_VAR(struct native_rtp_bridge_data *, data, bridge_channel->tech_pvt, ao2_cleanup);
444
445         if (!data) {
446                 return;
447         }
448
449         ast_channel_lock(bridge_channel->chan);
450         ast_framehook_detach(bridge_channel->chan, data->id);
451         data->detached = 1;
452         ast_channel_unlock(bridge_channel->chan);
453         bridge_channel->tech_pvt = NULL;
454 }
455
456 static int native_rtp_bridge_join(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel)
457 {
458         native_rtp_bridge_framehook_detach(bridge_channel);
459         if (native_rtp_bridge_framehook_attach(bridge_channel)) {
460                 return -1;
461         }
462
463         native_rtp_bridge_start(bridge, NULL);
464         return 0;
465 }
466
467 static void native_rtp_bridge_unsuspend(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel)
468 {
469         native_rtp_bridge_join(bridge, bridge_channel);
470 }
471
472 static void native_rtp_bridge_leave(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel)
473 {
474         native_rtp_bridge_framehook_detach(bridge_channel);
475         native_rtp_bridge_stop(bridge, NULL);
476 }
477
478 static int native_rtp_bridge_write(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, struct ast_frame *frame)
479 {
480         return ast_bridge_queue_everyone_else(bridge, bridge_channel, frame);
481 }
482
483 static struct ast_bridge_technology native_rtp_bridge = {
484         .name = "native_rtp",
485         .capabilities = AST_BRIDGE_CAPABILITY_NATIVE,
486         .preference = AST_BRIDGE_PREFERENCE_BASE_NATIVE,
487         .join = native_rtp_bridge_join,
488         .unsuspend = native_rtp_bridge_unsuspend,
489         .leave = native_rtp_bridge_leave,
490         .suspend = native_rtp_bridge_leave,
491         .write = native_rtp_bridge_write,
492         .compatible = native_rtp_bridge_compatible,
493 };
494
495 static int unload_module(void)
496 {
497         ast_bridge_technology_unregister(&native_rtp_bridge);
498         return 0;
499 }
500
501 static int load_module(void)
502 {
503         if (ast_bridge_technology_register(&native_rtp_bridge)) {
504                 unload_module();
505                 return AST_MODULE_LOAD_DECLINE;
506         }
507         return AST_MODULE_LOAD_SUCCESS;
508 }
509
510 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Native RTP bridging module");