xref: /btstack/src/classic/avdtp_util.c (revision c37cd8f3d1350b92a2f66c31b2a5fcd75f8c91a4)
1 /*
2  * Copyright (C) 2016 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define __BTSTACK_FILE__ "avdtp_util.c"
39 
40 
41 #include <stdint.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #include "btstack.h"
47 #include "avdtp.h"
48 #include "avdtp_util.h"
49 
50 #define MAX_MEDIA_CODEC_INFORMATION_LENGTH 100
51 
52 static const char * avdtp_si_name[] = {
53     "ERROR",
54     "AVDTP_SI_DISCOVER",
55     "AVDTP_SI_GET_CAPABILITIES",
56     "AVDTP_SI_SET_CONFIGURATION",
57     "AVDTP_SI_GET_CONFIGURATION",
58     "AVDTP_SI_RECONFIGURE",
59     "AVDTP_SI_OPEN",
60     "AVDTP_SI_START",
61     "AVDTP_SI_CLOSE",
62     "AVDTP_SI_SUSPEND",
63     "AVDTP_SI_ABORT",
64     "AVDTP_SI_SECURITY_CONTROL",
65     "AVDTP_SI_GET_ALL_CAPABILITIES",
66     "AVDTP_SI_DELAY_REPORT"
67 };
68 const char * avdtp_si2str(uint16_t index){
69     if (index <= 0 || index > sizeof(avdtp_si_name)) return avdtp_si_name[0];
70     return avdtp_si_name[index];
71 }
72 
73 void avdtp_initialize_stream_endpoint(avdtp_stream_endpoint_t * stream_endpoint){
74     stream_endpoint->connection = NULL;
75     stream_endpoint->state = AVDTP_STREAM_ENDPOINT_IDLE;
76     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE;
77     stream_endpoint->initiator_config_state = AVDTP_INITIATOR_STREAM_CONFIG_IDLE;
78     stream_endpoint->remote_sep_index = AVDTP_INVALID_SEP_INDEX;
79     stream_endpoint->media_disconnect = 0;
80     stream_endpoint->sep.in_use = 0;
81     stream_endpoint->remote_sep_index = 0;
82 }
83 
84 avdtp_stream_endpoint_t * avdtp_stream_endpoint_for_seid(uint16_t seid, avdtp_context_t * context){
85     btstack_linked_list_iterator_t it;
86     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
87     while (btstack_linked_list_iterator_has_next(&it)){
88         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
89         if (stream_endpoint->sep.seid == seid){
90             return stream_endpoint;
91         }
92     }
93     return NULL;
94 }
95 
96 avdtp_connection_t * avdtp_connection_for_bd_addr(bd_addr_t addr, avdtp_context_t * context){
97     btstack_linked_list_iterator_t it;
98     btstack_linked_list_iterator_init(&it, &context->connections);
99     while (btstack_linked_list_iterator_has_next(&it)){
100         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
101         if (memcmp(addr, connection->remote_addr, 6) != 0) continue;
102         return connection;
103     }
104     return NULL;
105 }
106 
107 avdtp_connection_t * avdtp_connection_for_avdtp_cid(uint16_t avdtp_cid, avdtp_context_t * context){
108     btstack_linked_list_iterator_t it;
109     btstack_linked_list_iterator_init(&it, &context->connections);
110     while (btstack_linked_list_iterator_has_next(&it)){
111         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
112         if (connection->avdtp_cid != avdtp_cid) continue;
113         return connection;
114     }
115     return NULL;
116 }
117 
118 avdtp_connection_t * avdtp_connection_for_l2cap_signaling_cid(uint16_t l2cap_cid, avdtp_context_t * context){
119     btstack_linked_list_iterator_t it;
120     btstack_linked_list_iterator_init(&it, &context->connections);
121     while (btstack_linked_list_iterator_has_next(&it)){
122         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
123         if (connection->l2cap_signaling_cid != l2cap_cid) continue;
124         return connection;
125     }
126     return NULL;
127 }
128 
129 avdtp_stream_endpoint_t * avdtp_stream_endpoint_for_l2cap_cid(uint16_t l2cap_cid, avdtp_context_t * context){
130     btstack_linked_list_iterator_t it;
131     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
132     while (btstack_linked_list_iterator_has_next(&it)){
133         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
134         if (stream_endpoint->l2cap_media_cid == l2cap_cid){
135             return stream_endpoint;
136         }
137         if (stream_endpoint->l2cap_reporting_cid == l2cap_cid){
138             return stream_endpoint;
139         }
140         if (stream_endpoint->l2cap_recovery_cid == l2cap_cid){
141             return stream_endpoint;
142         }
143     }
144     return NULL;
145 }
146 
147 avdtp_stream_endpoint_t * avdtp_stream_endpoint_for_signaling_cid(uint16_t l2cap_cid, avdtp_context_t * context){
148     btstack_linked_list_iterator_t it;
149     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
150     while (btstack_linked_list_iterator_has_next(&it)){
151         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
152         if (stream_endpoint->connection){
153             if (stream_endpoint->connection->l2cap_signaling_cid == l2cap_cid){
154                 return stream_endpoint;
155             }
156         }
157     }
158     return NULL;
159 }
160 
161 avdtp_stream_endpoint_t * avdtp_stream_endpoint_with_seid(uint8_t seid, avdtp_context_t * context){
162     btstack_linked_list_iterator_t it;
163     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
164     while (btstack_linked_list_iterator_has_next(&it)){
165         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
166         if (stream_endpoint->sep.seid == seid){
167             return stream_endpoint;
168         }
169     }
170     return NULL;
171 }
172 
173 avdtp_stream_endpoint_t * avdtp_stream_endpoint_associated_with_acp_seid(uint16_t acp_seid, avdtp_context_t * context){
174     btstack_linked_list_iterator_t it;
175     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
176     while (btstack_linked_list_iterator_has_next(&it)){
177         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
178 
179         if (stream_endpoint->remote_sep_index != AVDTP_INVALID_SEP_INDEX){
180             if (!stream_endpoint->connection) continue;
181             if (stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].seid == acp_seid){
182                 return stream_endpoint;
183             }
184         }
185     }
186     return NULL;
187 }
188 
189 int get_bit16(uint16_t bitmap, int position){
190     return (bitmap >> position) & 1;
191 }
192 
193 uint8_t store_bit16(uint16_t bitmap, int position, uint8_t value){
194     if (value){
195         bitmap |= 1 << position;
196     } else {
197         bitmap &= ~ (1 << position);
198     }
199     return bitmap;
200 }
201 
202 int avdtp_read_signaling_header(avdtp_signaling_packet_t * signaling_header, uint8_t * packet, uint16_t size){
203     int pos = 0;
204     if (size < 2) return pos;
205     signaling_header->transaction_label = packet[pos] >> 4;
206     signaling_header->packet_type = (avdtp_packet_type_t)((packet[pos] >> 2) & 0x03);
207     signaling_header->message_type = (avdtp_message_type_t) (packet[pos] & 0x03);
208     pos++;
209     memset(signaling_header->command, 0, sizeof(signaling_header->command));
210     switch (signaling_header->packet_type){
211         case AVDTP_SINGLE_PACKET:
212             signaling_header->num_packets = 0;
213             signaling_header->offset = 0;
214             signaling_header->size = 0;
215             break;
216         case AVDTP_END_PACKET:
217             signaling_header->num_packets = 0;
218             break;
219         case AVDTP_START_PACKET:
220             signaling_header->num_packets = packet[pos++];
221             signaling_header->size = 0;
222             signaling_header->offset = 0;
223             break;
224         case AVDTP_CONTINUE_PACKET:
225             if (signaling_header->num_packets <= 0) {
226                 log_info("    ERROR: wrong num fragmented packets\n");
227                 break;
228             }
229             signaling_header->num_packets--;
230             break;
231     }
232     signaling_header->signal_identifier = (avdtp_signal_identifier_t)(packet[pos++] & 0x3f);
233     return pos;
234 }
235 
236 int avdtp_pack_service_capabilities(uint8_t * buffer, int size, avdtp_capabilities_t caps, avdtp_service_category_t category, uint8_t pack_all_capabilities){
237     UNUSED(size);
238 
239     int i;
240     // pos = 0 reserved for length
241     int pos = 1;
242     switch(category){
243         case AVDTP_MEDIA_TRANSPORT:
244         case AVDTP_REPORTING:
245             break;
246         case AVDTP_DELAY_REPORTING:
247             if (!pack_all_capabilities) break;
248             break;
249         case AVDTP_RECOVERY:
250             buffer[pos++] = caps.recovery.recovery_type; // 0x01=RFC2733
251             buffer[pos++] = caps.recovery.maximum_recovery_window_size;
252             buffer[pos++] = caps.recovery.maximum_number_media_packets;
253             break;
254         case AVDTP_CONTENT_PROTECTION:
255             buffer[pos++] = caps.content_protection.cp_type_value_len + 2;
256             big_endian_store_16(buffer, pos, caps.content_protection.cp_type);
257             pos += 2;
258             memcpy(buffer+pos, caps.content_protection.cp_type_value, caps.content_protection.cp_type_value_len);
259             break;
260         case AVDTP_HEADER_COMPRESSION:
261             buffer[pos++] = (caps.header_compression.back_ch << 7) | (caps.header_compression.media << 6) | (caps.header_compression.recovery << 5);
262             break;
263         case AVDTP_MULTIPLEXING:
264             buffer[pos++] = caps.multiplexing_mode.fragmentation << 7;
265             for (i=0; i<caps.multiplexing_mode.transport_identifiers_num; i++){
266                 buffer[pos++] = caps.multiplexing_mode.transport_session_identifiers[i] << 7;
267                 buffer[pos++] = caps.multiplexing_mode.tcid[i] << 7;
268                 // media, reporting. recovery
269             }
270             break;
271         case AVDTP_MEDIA_CODEC:
272             buffer[pos++] = ((uint8_t)caps.media_codec.media_type) << 4;
273             buffer[pos++] = (uint8_t)caps.media_codec.media_codec_type;
274             for (i = 0; i<caps.media_codec.media_codec_information_len; i++){
275                 buffer[pos++] = caps.media_codec.media_codec_information[i];
276             }
277             break;
278         default:
279             break;
280     }
281     buffer[0] = pos - 1; // length
282     return pos;
283 }
284 
285 static int avdtp_unpack_service_capabilities_has_errors(avdtp_connection_t * connection, avdtp_service_category_t category, uint8_t cap_len){
286     connection->error_code = 0;
287 
288     if (category == AVDTP_SERVICE_CATEGORY_INVALID_0 ||
289         (category == AVDTP_SERVICE_CATEGORY_INVALID_FF && connection->signaling_packet.signal_identifier == AVDTP_SI_RECONFIGURE)){
290         log_info("    ERROR: BAD SERVICE CATEGORY %d\n", category);
291         connection->reject_service_category = category;
292         connection->error_code = BAD_SERV_CATEGORY;
293         return 1;
294     }
295 
296     if (connection->signaling_packet.signal_identifier == AVDTP_SI_RECONFIGURE){
297         if (category != AVDTP_CONTENT_PROTECTION && category != AVDTP_MEDIA_CODEC){
298             log_info("    ERROR: REJECT CATEGORY, INVALID_CAPABILITIES\n");
299             connection->reject_service_category = category;
300             connection->error_code = INVALID_CAPABILITIES;
301             return 1;
302         }
303     }
304 
305     switch(category){
306         case AVDTP_MEDIA_TRANSPORT:
307             if (cap_len != 0){
308                 log_info("    ERROR: REJECT CATEGORY, BAD_MEDIA_TRANSPORT\n");
309                 connection->reject_service_category = category;
310                 connection->error_code = BAD_MEDIA_TRANSPORT_FORMAT;
311                 return 1;
312             }
313             break;
314         case AVDTP_REPORTING:
315         case AVDTP_DELAY_REPORTING:
316             if (cap_len != 0){
317                 log_info("    ERROR: REJECT CATEGORY, BAD_LENGTH\n");
318                 connection->reject_service_category = category;
319                 connection->error_code = BAD_LENGTH;
320                 return 1;
321             }
322             break;
323         case AVDTP_RECOVERY:
324             if (cap_len < 3){
325                 log_info("    ERROR: REJECT CATEGORY, BAD_MEDIA_TRANSPORT\n");
326                 connection->reject_service_category = category;
327                 connection->error_code = BAD_RECOVERY_FORMAT;
328                 return 1;
329             }
330             break;
331         case AVDTP_CONTENT_PROTECTION:
332             if (cap_len < 2){
333                 log_info("    ERROR: REJECT CATEGORY, BAD_CP_FORMAT\n");
334                 connection->reject_service_category = category;
335                 connection->error_code = BAD_CP_FORMAT;
336                 return 1;
337             }
338             break;
339         case AVDTP_HEADER_COMPRESSION:
340             break;
341         case AVDTP_MULTIPLEXING:
342             break;
343         case AVDTP_MEDIA_CODEC:
344             break;
345         default:
346             break;
347     }
348     return 0;
349 }
350 
351 uint16_t avdtp_unpack_service_capabilities(avdtp_connection_t * connection, avdtp_capabilities_t * caps, uint8_t * packet, uint16_t size){
352     if (size == 0) return 0;
353 
354     uint16_t registered_service_categories = 0;
355     int pos = 0;
356     int i;
357     avdtp_service_category_t category = (avdtp_service_category_t)packet[pos++];
358     uint8_t cap_len = packet[pos++];
359 
360     if (avdtp_unpack_service_capabilities_has_errors(connection, category, cap_len)) return 0;
361     int processed_cap_len = 0;
362     int rfa = 0;
363 
364     while (pos < size){
365         if (cap_len > size - pos){
366             connection->reject_service_category = category;
367             connection->error_code = BAD_LENGTH;
368             return 0;
369         }
370         rfa = 0;
371         processed_cap_len = pos;
372         switch(category){
373             case AVDTP_RECOVERY:
374                 caps->recovery.recovery_type = packet[pos++];
375                 caps->recovery.maximum_recovery_window_size = packet[pos++];
376                 caps->recovery.maximum_number_media_packets = packet[pos++];
377                 break;
378             case AVDTP_CONTENT_PROTECTION:
379                 caps->content_protection.cp_type = big_endian_read_16(packet, pos);
380                 pos+=2;
381 
382                 caps->content_protection.cp_type_value_len = cap_len - 2;
383                 pos += caps->content_protection.cp_type_value_len;
384 
385                 // connection->reject_service_category = category;
386                 // connection->error_code = UNSUPPORTED_CONFIGURATION;
387                 // support for content protection goes here
388                 break;
389 
390             case AVDTP_HEADER_COMPRESSION:
391                 caps->header_compression.back_ch  = packet[pos] >> 7;
392                 caps->header_compression.media    = packet[pos] >> 6;
393                 caps->header_compression.recovery = packet[pos] >> 5;
394                 pos++;
395                 break;
396             case AVDTP_MULTIPLEXING:
397                 caps->multiplexing_mode.fragmentation = packet[pos++] >> 7;
398                 // read [tsid, tcid] for media, reporting. recovery respectively
399                 caps->multiplexing_mode.transport_identifiers_num = 3;
400                 for (i=0; i<caps->multiplexing_mode.transport_identifiers_num; i++){
401                     caps->multiplexing_mode.transport_session_identifiers[i] = packet[pos++] >> 7;
402                     caps->multiplexing_mode.tcid[i] = packet[pos++] >> 7;
403                 }
404                 break;
405             case AVDTP_MEDIA_CODEC:
406                 caps->media_codec.media_type = (avdtp_media_type_t)(packet[pos++] >> 4);
407                 caps->media_codec.media_codec_type = (avdtp_media_codec_type_t)(packet[pos++]);
408                 caps->media_codec.media_codec_information_len = cap_len - 2;
409                 caps->media_codec.media_codec_information = &packet[pos];
410                 pos += caps->media_codec.media_codec_information_len;
411                 break;
412             case AVDTP_MEDIA_TRANSPORT:
413             case AVDTP_REPORTING:
414             case AVDTP_DELAY_REPORTING:
415                 pos += cap_len;
416                 break;
417             default:
418                 pos += cap_len;
419                 rfa = 1;
420                 break;
421         }
422         processed_cap_len = pos - processed_cap_len;
423 
424         if (cap_len == processed_cap_len){
425             if (!rfa) {
426                 registered_service_categories = store_bit16(registered_service_categories, category, 1);
427             }
428             if (pos < size-2){
429                 //int old_pos = pos;
430                 category = (avdtp_service_category_t)packet[pos++];
431                 cap_len = packet[pos++];
432                 if (avdtp_unpack_service_capabilities_has_errors(connection, category, cap_len)) return 0;
433             }
434         }
435     }
436     return registered_service_categories;
437 }
438 
439 void avdtp_prepare_capabilities(avdtp_signaling_packet_t * signaling_packet, uint8_t transaction_label, uint16_t registered_service_categories, avdtp_capabilities_t capabilities, uint8_t identifier){
440     if (signaling_packet->offset) return;
441     uint8_t pack_all_capabilities = 1;
442     signaling_packet->message_type = AVDTP_RESPONSE_ACCEPT_MSG;
443     int i;
444 
445     signaling_packet->size = 0;
446     memset(signaling_packet->command, 0 , sizeof(signaling_packet->command));
447 
448 
449     switch (identifier) {
450         case AVDTP_SI_GET_CAPABILITIES:
451             pack_all_capabilities = 0;
452             break;
453         case AVDTP_SI_GET_ALL_CAPABILITIES:
454             pack_all_capabilities = 1;
455             break;
456         case AVDTP_SI_SET_CONFIGURATION:
457             signaling_packet->command[signaling_packet->size++] = signaling_packet->acp_seid << 2;
458             signaling_packet->command[signaling_packet->size++] = signaling_packet->int_seid << 2;
459             signaling_packet->message_type = AVDTP_CMD_MSG;
460             break;
461         case AVDTP_SI_RECONFIGURE:
462             signaling_packet->command[signaling_packet->size++] = signaling_packet->acp_seid << 2;
463             signaling_packet->message_type = AVDTP_CMD_MSG;
464             break;
465         default:
466             log_error("avdtp_prepare_capabilities wrong identifier %d", identifier);
467             break;
468     }
469 
470     for (i = 1; i < 9; i++){
471         int registered_category = get_bit16(registered_service_categories, i);
472         if (!registered_category && (identifier == AVDTP_SI_SET_CONFIGURATION || identifier == AVDTP_SI_RECONFIGURE)){
473             // TODO: introduce bitmap of mandatory categories
474             if (i == 1){
475                 registered_category = 1;
476             }
477         }
478         if (registered_category){
479             // service category
480             signaling_packet->command[signaling_packet->size++] = i;
481             signaling_packet->size += avdtp_pack_service_capabilities(signaling_packet->command+signaling_packet->size, sizeof(signaling_packet->command)-signaling_packet->size, capabilities, (avdtp_service_category_t)i, pack_all_capabilities);
482         }
483     }
484 
485     signaling_packet->signal_identifier = (avdtp_signal_identifier_t)identifier;
486     signaling_packet->transaction_label = transaction_label;
487 }
488 
489 int avdtp_signaling_create_fragment(uint16_t cid, avdtp_signaling_packet_t * signaling_packet, uint8_t * out_buffer) {
490     int mtu = l2cap_get_remote_mtu_for_local_cid(cid);
491     int data_len = 0;
492 
493     uint16_t offset = signaling_packet->offset;
494     uint16_t pos = 1;
495 
496     if (offset == 0){
497         if (signaling_packet->size <= mtu - 2){
498             signaling_packet->packet_type = AVDTP_SINGLE_PACKET;
499             out_buffer[pos++] = signaling_packet->signal_identifier;
500             data_len = signaling_packet->size;
501         } else {
502             signaling_packet->packet_type = AVDTP_START_PACKET;
503             out_buffer[pos++] = (mtu + signaling_packet->size)/ (mtu-1);
504             out_buffer[pos++] = signaling_packet->signal_identifier;
505             data_len = mtu - 3;
506             signaling_packet->offset = data_len;
507         }
508     } else {
509         int remaining_bytes = signaling_packet->size - offset;
510         if (remaining_bytes <= mtu - 1){
511             signaling_packet->packet_type = AVDTP_END_PACKET;
512             data_len = remaining_bytes;
513             signaling_packet->offset = 0;
514         } else{
515             signaling_packet->packet_type = AVDTP_CONTINUE_PACKET;
516             data_len = mtu - 1;
517             signaling_packet->offset += data_len;
518         }
519     }
520     out_buffer[0] = avdtp_header(signaling_packet->transaction_label, signaling_packet->packet_type, signaling_packet->message_type);
521     memcpy(out_buffer+pos, signaling_packet->command + offset, data_len);
522     pos += data_len;
523     return pos;
524 }
525 
526 
527 void avdtp_signaling_emit_connection_established(btstack_packet_handler_t callback, uint16_t avdtp_cid, bd_addr_t addr, uint8_t status){
528     if (!callback) return;
529     uint8_t event[12];
530     int pos = 0;
531     event[pos++] = HCI_EVENT_AVDTP_META;
532     event[pos++] = sizeof(event) - 2;
533     event[pos++] = AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED;
534     little_endian_store_16(event, pos, avdtp_cid);
535     pos += 2;
536     reverse_bd_addr(addr,&event[pos]);
537     pos += 6;
538     event[pos++] = status;
539     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
540 }
541 
542 void avdtp_streaming_emit_can_send_media_packet_now(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t seid, uint16_t sequence_number){
543     if (!callback) return;
544     uint8_t event[8];
545     int pos = 0;
546     event[pos++] = HCI_EVENT_AVDTP_META;
547     event[pos++] = sizeof(event) - 2;
548     event[pos++] = AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW;
549     little_endian_store_16(event, pos, avdtp_cid);
550     pos += 2;
551     event[pos++] = seid;
552     little_endian_store_16(event, pos, sequence_number);
553     pos += 2;
554     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
555 }
556 
557 void avdtp_signaling_emit_connection_released(btstack_packet_handler_t callback, uint16_t avdtp_cid){
558     if (!callback) return;
559     uint8_t event[5];
560     int pos = 0;
561     event[pos++] = HCI_EVENT_AVDTP_META;
562     event[pos++] = sizeof(event) - 2;
563     event[pos++] = AVDTP_SUBEVENT_SIGNALING_CONNECTION_RELEASED;
564     little_endian_store_16(event, pos, avdtp_cid);
565     pos += 2;
566     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
567 }
568 
569 void avdtp_streaming_emit_connection_released(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid){
570     if (!callback) return;
571     uint8_t event[6];
572     int pos = 0;
573     event[pos++] = HCI_EVENT_AVDTP_META;
574     event[pos++] = sizeof(event) - 2;
575     event[pos++] = AVDTP_SUBEVENT_STREAMING_CONNECTION_RELEASED;
576     little_endian_store_16(event, pos, avdtp_cid);
577     pos += 2;
578     event[pos++] = local_seid;
579     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
580 }
581 
582 void avdtp_streaming_emit_connection_established(btstack_packet_handler_t callback, uint16_t avdtp_cid, bd_addr_t addr, uint8_t local_seid, uint8_t remote_seid, uint8_t status){
583     if (!callback) return;
584     uint8_t event[14];
585     int pos = 0;
586     event[pos++] = HCI_EVENT_AVDTP_META;
587     event[pos++] = sizeof(event) - 2;
588     event[pos++] = AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED;
589     little_endian_store_16(event, pos, avdtp_cid);
590     pos += 2;
591     reverse_bd_addr(addr,&event[pos]);
592     pos += 6;
593     event[pos++] = local_seid;
594     event[pos++] = remote_seid;
595     event[pos++] = status;
596     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
597 }
598 
599 void avdtp_signaling_emit_sep(btstack_packet_handler_t callback, uint16_t avdtp_cid, avdtp_sep_t sep){
600     if (!callback) return;
601     uint8_t event[9];
602     int pos = 0;
603     event[pos++] = HCI_EVENT_AVDTP_META;
604     event[pos++] = sizeof(event) - 2;
605     event[pos++] = AVDTP_SUBEVENT_SIGNALING_SEP_FOUND;
606     little_endian_store_16(event, pos, avdtp_cid);
607     pos += 2;
608     event[pos++] = sep.seid;
609     event[pos++] = sep.in_use;
610     event[pos++] = sep.media_type;
611     event[pos++] = sep.type;
612     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
613 }
614 
615 void avdtp_signaling_emit_accept(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, avdtp_signal_identifier_t identifier){
616     if (!callback) return;
617     uint8_t event[7];
618     int pos = 0;
619     event[pos++] = HCI_EVENT_AVDTP_META;
620     event[pos++] = sizeof(event) - 2;
621     event[pos++] = AVDTP_SUBEVENT_SIGNALING_ACCEPT;
622     little_endian_store_16(event, pos, avdtp_cid);
623     pos += 2;
624     event[pos++] = local_seid;
625     event[pos++] = identifier;
626     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
627 }
628 
629 void avdtp_signaling_emit_reject(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, avdtp_signal_identifier_t identifier){
630     if (!callback) return;
631     uint8_t event[7];
632     int pos = 0;
633     event[pos++] = HCI_EVENT_AVDTP_META;
634     event[pos++] = sizeof(event) - 2;
635     event[pos++] = AVDTP_SUBEVENT_SIGNALING_REJECT;
636     little_endian_store_16(event, pos, avdtp_cid);
637     pos += 2;
638     event[pos++] = local_seid;
639     event[pos++] = identifier;
640     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
641 }
642 
643 void avdtp_signaling_emit_general_reject(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, avdtp_signal_identifier_t identifier){
644     if (!callback) return;
645     uint8_t event[7];
646     int pos = 0;
647     event[pos++] = HCI_EVENT_AVDTP_META;
648     event[pos++] = sizeof(event) - 2;
649     event[pos++] = AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT;
650     little_endian_store_16(event, pos, avdtp_cid);
651     pos += 2;
652     event[pos++] = local_seid;
653     event[pos++] = identifier;
654     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
655 }
656 
657 void avdtp_signaling_emit_media_codec_sbc_capability(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec){
658     if (!callback) return;
659     uint8_t event[15];
660     int pos = 0;
661     event[pos++] = HCI_EVENT_AVDTP_META;
662     event[pos++] = sizeof(event) - 2;
663     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY;
664     little_endian_store_16(event, pos, avdtp_cid);
665     pos += 2;
666     event[pos++] = local_seid;
667     event[pos++] = remote_seid;
668     event[pos++] = media_codec.media_type;
669     event[pos++] = media_codec.media_codec_information[0] >> 4;
670     event[pos++] = media_codec.media_codec_information[0] & 0x0F;
671     event[pos++] = media_codec.media_codec_information[1] >> 4;
672     event[pos++] = (media_codec.media_codec_information[1] & 0x0F) >> 2;
673     event[pos++] = media_codec.media_codec_information[1] & 0x03;
674     event[pos++] = media_codec.media_codec_information[2];
675     event[pos++] = media_codec.media_codec_information[3];
676     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
677 }
678 
679 void avdtp_signaling_emit_media_codec_other_capability(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec){
680     if (!callback) return;
681         uint8_t event[111];
682     int pos = 0;
683     event[pos++] = HCI_EVENT_AVDTP_META;
684     event[pos++] = sizeof(event) - 2;
685     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY;
686     little_endian_store_16(event, pos, avdtp_cid);
687     pos += 2;
688     event[pos++] = local_seid;
689     event[pos++] = remote_seid;
690     event[pos++] = media_codec.media_type;
691     little_endian_store_16(event, pos, media_codec.media_codec_type);
692     pos += 2;
693     little_endian_store_16(event, pos, media_codec.media_codec_information_len);
694     pos += 2;
695     if (media_codec.media_codec_information_len < 100){
696         memcpy(event+pos, media_codec.media_codec_information, media_codec.media_codec_information_len);
697     } else {
698         memcpy(event+pos, media_codec.media_codec_information, 100);
699     }
700     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
701 }
702 
703 static inline void avdtp_signaling_emit_media_codec_sbc(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid,
704     avdtp_media_type_t media_type, const uint8_t * media_codec_information, uint8_t reconfigure){
705     if (!callback) return;
706     uint8_t event[16+2];
707     int pos = 0;
708     event[pos++] = HCI_EVENT_AVDTP_META;
709     event[pos++] = sizeof(event) - 2;
710 
711     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION;
712     little_endian_store_16(event, pos, avdtp_cid);
713     pos += 2;
714     event[pos++] = local_seid;
715     event[pos++] = remote_seid;
716     event[pos++] = reconfigure;
717 
718     uint8_t num_channels = 0;
719     uint16_t sampling_frequency = 0;
720     uint8_t subbands = 0;
721     uint8_t block_length = 0;
722 
723     uint8_t sampling_frequency_bitmap = media_codec_information[0] >> 4;
724     uint8_t channel_mode_bitmap = media_codec_information[0] & 0x0F;
725     uint8_t block_length_bitmap = media_codec_information[1] >> 4;
726     uint8_t subbands_bitmap = (media_codec_information[1] & 0x0F) >> 2;
727 
728     if (channel_mode_bitmap & AVDTP_SBC_MONO){
729         num_channels = 1;
730     }
731     if ( (channel_mode_bitmap & AVDTP_SBC_JOINT_STEREO) ||
732          (channel_mode_bitmap & AVDTP_SBC_STEREO) ||
733          (channel_mode_bitmap & AVDTP_SBC_DUAL_CHANNEL) ){
734         num_channels = 2;
735     }
736 
737     if (sampling_frequency_bitmap & AVDTP_SBC_16000){
738         sampling_frequency = 16000;
739     }
740     if (sampling_frequency_bitmap & AVDTP_SBC_32000){
741         sampling_frequency = 32000;
742     }
743     if (sampling_frequency_bitmap & AVDTP_SBC_44100){
744         sampling_frequency = 44100;
745     }
746     if (sampling_frequency_bitmap & AVDTP_SBC_48000){
747         sampling_frequency = 48000;
748     }
749 
750     if (subbands_bitmap & AVDTP_SBC_SUBBANDS_4){
751         subbands = 4;
752     }
753     if (subbands_bitmap & AVDTP_SBC_SUBBANDS_8){
754         subbands = 8;
755     }
756 
757     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_4){
758         block_length = 4;
759     }
760     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_8){
761         block_length = 8;
762     }
763     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_12){
764         block_length = 12;
765     }
766     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_16){
767         block_length = 16;
768     }
769 
770     event[pos++] = media_type;
771     little_endian_store_16(event, pos, sampling_frequency);
772     pos += 2;
773 
774     event[pos++] = channel_mode_bitmap;
775     event[pos++] = num_channels;
776     event[pos++] = block_length;
777     event[pos++] = subbands;
778     event[pos++] = media_codec_information[1] & 0x03;
779     event[pos++] = media_codec_information[2];
780     event[pos++] = media_codec_information[3];
781     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
782 }
783 
784 void avdtp_signaling_emit_media_codec_sbc_configuration(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, avdtp_media_type_t media_type, const uint8_t * media_codec_information){
785     if (!callback) return;
786     avdtp_signaling_emit_media_codec_sbc(callback, avdtp_cid, local_seid, remote_seid, media_type, media_codec_information, 0);
787 }
788 
789 void avdtp_signaling_emit_media_codec_sbc_reconfiguration(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, avdtp_media_type_t media_type, const uint8_t * media_codec_information){
790     if (!callback) return;
791     avdtp_signaling_emit_media_codec_sbc(callback, avdtp_cid, local_seid, remote_seid, media_type, media_codec_information, 1);
792 }
793 
794 static inline void avdtp_signaling_emit_media_codec_other(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec, uint8_t reconfigure){
795     uint8_t event[MAX_MEDIA_CODEC_INFORMATION_LENGTH + 13];
796     int pos = 0;
797     event[pos++] = HCI_EVENT_AVDTP_META;
798     event[pos++] = sizeof(event) - 2;
799     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION;
800     little_endian_store_16(event, pos, avdtp_cid);
801     pos += 2;
802     event[pos++] = local_seid;
803     event[pos++] = remote_seid;
804     event[pos++] = reconfigure;
805     event[pos++] = media_codec.media_type;
806     little_endian_store_16(event, pos, media_codec.media_codec_type);
807     pos += 2;
808     little_endian_store_16(event, pos, media_codec.media_codec_information_len);
809     pos += 2;
810 
811     int media_codec_len = btstack_min(MAX_MEDIA_CODEC_INFORMATION_LENGTH, media_codec.media_codec_information_len);
812     memcpy(event+pos, media_codec.media_codec_information, media_codec_len);
813 
814     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
815 }
816 
817 void avdtp_signaling_emit_media_codec_other_configuration(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec){
818     if (!callback) return;
819     avdtp_signaling_emit_media_codec_other(callback, avdtp_cid, local_seid, remote_seid, media_codec, 0);
820 }
821 
822 void avdtp_signaling_emit_media_codec_other_reconfiguration(btstack_packet_handler_t callback, uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec){
823     if (!callback) return;
824     avdtp_signaling_emit_media_codec_other(callback, avdtp_cid, local_seid, remote_seid, media_codec, 1);
825 }
826 
827 
828 void avdtp_request_can_send_now_acceptor(avdtp_connection_t * connection, uint16_t l2cap_cid){
829     if (!connection) return;
830     connection->wait_to_send_acceptor = 1;
831     l2cap_request_can_send_now_event(l2cap_cid);
832 }
833 void avdtp_request_can_send_now_initiator(avdtp_connection_t * connection, uint16_t l2cap_cid){
834     if (!connection) return;
835     connection->wait_to_send_initiator = 1;
836     l2cap_request_can_send_now_event(l2cap_cid);
837 }
838 void avdtp_request_can_send_now_self(avdtp_connection_t * connection, uint16_t l2cap_cid){
839     if (!connection) return;
840     connection->wait_to_send_self = 1;
841     l2cap_request_can_send_now_event(l2cap_cid);
842 }
843 
844 uint8_t avdtp_get_index_of_remote_stream_endpoint_with_seid(avdtp_stream_endpoint_t * stream_endpoint, uint16_t seid){
845     if (!stream_endpoint->connection) return AVDTP_INVALID_SEP_INDEX;
846     if (stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].seid == seid){
847         return stream_endpoint->remote_sep_index;
848     }
849     int i;
850     for (i=0; i < stream_endpoint->connection->remote_seps_num; i++){
851         if (stream_endpoint->connection->remote_seps[i].seid == seid){
852             return i;
853         }
854     }
855     return AVDTP_INVALID_SEP_INDEX;
856 }
857 
858 uint8_t avdtp_find_remote_sep(avdtp_connection_t * connection, uint8_t remote_seid){
859     if (!connection) return AVDTP_INVALID_SEP_INDEX;
860     int i;
861     for (i = 0; i < connection->remote_seps_num; i++){
862         if (connection->remote_seps[i].seid == remote_seid){
863             return i;
864         }
865     }
866     return AVDTP_INVALID_SEP_INDEX;
867 }
868 
869 
870 uint8_t avdtp_local_seid(avdtp_stream_endpoint_t * stream_endpoint){
871     if (!stream_endpoint) return 0;
872     return stream_endpoint->sep.seid;
873 
874 }
875 
876 uint8_t avdtp_remote_seid(avdtp_stream_endpoint_t * stream_endpoint){
877     if (!stream_endpoint) return 0;
878     if (!stream_endpoint->connection) return 0;
879     return stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].seid;
880 }
881 
882 void a2dp_streaming_emit_connection_established(btstack_packet_handler_t callback, uint16_t cid, bd_addr_t addr, uint8_t local_seid, uint8_t remote_seid, uint8_t status){
883     if (!callback) return;
884     uint8_t event[14];
885     int pos = 0;
886     event[pos++] = HCI_EVENT_A2DP_META;
887     event[pos++] = sizeof(event) - 2;
888     event[pos++] = A2DP_SUBEVENT_STREAM_ESTABLISHED;
889     little_endian_store_16(event, pos, cid);
890     pos += 2;
891     reverse_bd_addr(addr,&event[pos]);
892     pos += 6;
893     event[pos++] = local_seid;
894     event[pos++] = remote_seid;
895     event[pos++] = status;
896     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
897 }
898