xref: /btstack/src/classic/avdtp_util.c (revision d4d8445570fbeab6a48c397749444927f1b272ee)
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 #include <unistd.h>
46 
47 #include "btstack.h"
48 #include "avdtp.h"
49 #include "avdtp_util.h"
50 
51 inline uint8_t avdtp_header(uint8_t tr_label, avdtp_packet_type_t packet_type, avdtp_message_type_t msg_type){
52     return (tr_label<<4) | ((uint8_t)packet_type<<2) | (uint8_t)msg_type;
53 }
54 
55 void avdtp_initialize_stream_endpoint(avdtp_stream_endpoint_t * stream_endpoint){
56     stream_endpoint->connection = NULL;
57     stream_endpoint->state = AVDTP_STREAM_ENDPOINT_IDLE;
58     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE;
59     stream_endpoint->initiator_config_state = AVDTP_INITIATOR_STREAM_CONFIG_IDLE;
60     stream_endpoint->remote_sep_index = AVDTP_INVALID_SEP_INDEX;
61     stream_endpoint->media_disconnect = 0;
62     stream_endpoint->remote_seps_num = 0;
63     stream_endpoint->sep.in_use = 0;
64     memset(stream_endpoint->remote_seps, 0, sizeof(stream_endpoint->remote_seps));
65 }
66 
67 avdtp_stream_endpoint_t * avdtp_stream_endpoint_for_seid(uint16_t seid, avdtp_context_t * context){
68     btstack_linked_list_iterator_t it;
69     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
70     while (btstack_linked_list_iterator_has_next(&it)){
71         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
72         if (stream_endpoint->sep.seid == seid){
73             return stream_endpoint;
74         }
75     }
76     return NULL;
77 }
78 
79 avdtp_connection_t * avdtp_connection_for_bd_addr(bd_addr_t addr, avdtp_context_t * context){
80     btstack_linked_list_iterator_t it;
81     btstack_linked_list_iterator_init(&it, &context->connections);
82     while (btstack_linked_list_iterator_has_next(&it)){
83         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
84         if (memcmp(addr, connection->remote_addr, 6) != 0) continue;
85         return connection;
86     }
87     return NULL;
88 }
89 
90 avdtp_connection_t * avdtp_connection_for_con_handle(hci_con_handle_t con_handle, avdtp_context_t * context){
91     btstack_linked_list_iterator_t it;
92     btstack_linked_list_iterator_init(&it, &context->connections);
93     while (btstack_linked_list_iterator_has_next(&it)){
94         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
95         if (connection->con_handle != con_handle) continue;
96         return connection;
97     }
98     return NULL;
99 }
100 
101 avdtp_connection_t * avdtp_connection_for_l2cap_signaling_cid(uint16_t l2cap_cid, avdtp_context_t * context){
102     btstack_linked_list_iterator_t it;
103     btstack_linked_list_iterator_init(&it, &context->connections);
104     while (btstack_linked_list_iterator_has_next(&it)){
105         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
106         if (connection->l2cap_signaling_cid != l2cap_cid) continue;
107         return connection;
108     }
109     return NULL;
110 }
111 
112 avdtp_stream_endpoint_t * avdtp_stream_endpoint_for_l2cap_cid(uint16_t l2cap_cid, avdtp_context_t * context){
113     btstack_linked_list_iterator_t it;
114     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
115     while (btstack_linked_list_iterator_has_next(&it)){
116         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
117         if (stream_endpoint->l2cap_media_cid == l2cap_cid){
118             return stream_endpoint;
119         }
120         if (stream_endpoint->l2cap_reporting_cid == l2cap_cid){
121             return stream_endpoint;
122         }
123         if (stream_endpoint->l2cap_recovery_cid == l2cap_cid){
124             return stream_endpoint;
125         }
126     }
127     return NULL;
128 }
129 
130 avdtp_stream_endpoint_t * avdtp_stream_endpoint_with_seid(uint8_t seid, avdtp_context_t * context){
131     btstack_linked_list_iterator_t it;
132     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
133     while (btstack_linked_list_iterator_has_next(&it)){
134         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
135         if (stream_endpoint->sep.seid == seid){
136             return stream_endpoint;
137         }
138     }
139     return NULL;
140 }
141 
142 avdtp_stream_endpoint_t * avdtp_stream_endpoint_associated_with_acp_seid(uint16_t acp_seid, avdtp_context_t * context){
143     btstack_linked_list_iterator_t it;
144     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
145     while (btstack_linked_list_iterator_has_next(&it)){
146         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
147         if (stream_endpoint->remote_sep_index != AVDTP_INVALID_SEP_INDEX){
148             if (stream_endpoint->remote_seps[stream_endpoint->remote_sep_index].seid == acp_seid){
149                 return stream_endpoint;
150             }
151         }
152     }
153     return NULL;
154 }
155 
156 int get_bit16(uint16_t bitmap, int position){
157     return (bitmap >> position) & 1;
158 }
159 
160 uint8_t store_bit16(uint16_t bitmap, int position, uint8_t value){
161     if (value){
162         bitmap |= 1 << position;
163     } else {
164         bitmap &= ~ (1 << position);
165     }
166     return bitmap;
167 }
168 
169 int avdtp_read_signaling_header(avdtp_signaling_packet_t * signaling_header, uint8_t * packet, uint16_t size){
170     int pos = 0;
171     if (size < 2) return pos;
172     signaling_header->transaction_label = packet[pos] >> 4;
173     signaling_header->packet_type = (avdtp_packet_type_t)((packet[pos] >> 2) & 0x03);
174     signaling_header->message_type = (avdtp_message_type_t) (packet[pos] & 0x03);
175     pos++;
176     memset(signaling_header->command, 0, sizeof(signaling_header->command));
177     switch (signaling_header->packet_type){
178         case AVDTP_SINGLE_PACKET:
179             signaling_header->num_packets = 0;
180             signaling_header->offset = 0;
181             signaling_header->size = 0;
182             break;
183         case AVDTP_END_PACKET:
184             signaling_header->num_packets = 0;
185             break;
186         case AVDTP_START_PACKET:
187             signaling_header->num_packets = packet[pos++];
188             signaling_header->size = 0;
189             signaling_header->offset = 0;
190             break;
191         case AVDTP_CONTINUE_PACKET:
192             if (signaling_header->num_packets <= 0) {
193                 printf("    ERROR: wrong num fragmented packets\n");
194                 break;
195             }
196             signaling_header->num_packets--;
197             break;
198     }
199     signaling_header->signal_identifier = packet[pos++] & 0x3f;
200     return pos;
201 }
202 
203 int avdtp_pack_service_capabilities(uint8_t * buffer, int size, avdtp_capabilities_t caps, avdtp_service_category_t category, uint8_t pack_all_capabilities){
204     UNUSED(size);
205 
206     int i;
207     // pos = 0 reserved for length
208     int pos = 1;
209     switch(category){
210         case AVDTP_MEDIA_TRANSPORT:
211         case AVDTP_REPORTING:
212             break;
213         case AVDTP_DELAY_REPORTING:
214             if (!pack_all_capabilities) break;
215             break;
216         case AVDTP_RECOVERY:
217             buffer[pos++] = caps.recovery.recovery_type; // 0x01=RFC2733
218             buffer[pos++] = caps.recovery.maximum_recovery_window_size;
219             buffer[pos++] = caps.recovery.maximum_number_media_packets;
220             break;
221         case AVDTP_CONTENT_PROTECTION:
222             buffer[pos++] = caps.content_protection.cp_type_value_len + 2;
223             big_endian_store_16(buffer, pos, caps.content_protection.cp_type);
224             pos += 2;
225             memcpy(buffer+pos, caps.content_protection.cp_type_value, caps.content_protection.cp_type_value_len);
226             break;
227         case AVDTP_HEADER_COMPRESSION:
228             buffer[pos++] = (caps.header_compression.back_ch << 7) | (caps.header_compression.media << 6) | (caps.header_compression.recovery << 5);
229             break;
230         case AVDTP_MULTIPLEXING:
231             buffer[pos++] = caps.multiplexing_mode.fragmentation << 7;
232             for (i=0; i<caps.multiplexing_mode.transport_identifiers_num; i++){
233                 buffer[pos++] = caps.multiplexing_mode.transport_session_identifiers[i] << 7;
234                 buffer[pos++] = caps.multiplexing_mode.tcid[i] << 7;
235                 // media, reporting. recovery
236             }
237             break;
238         case AVDTP_MEDIA_CODEC:
239             buffer[pos++] = ((uint8_t)caps.media_codec.media_type) << 4;
240             buffer[pos++] = (uint8_t)caps.media_codec.media_codec_type;
241             for (i = 0; i<caps.media_codec.media_codec_information_len; i++){
242                 buffer[pos++] = caps.media_codec.media_codec_information[i];
243             }
244             break;
245         default:
246             break;
247     }
248     buffer[0] = pos - 1; // length
249     return pos;
250 }
251 
252 static int avdtp_unpack_service_capabilities_has_errors(avdtp_connection_t * connection, avdtp_service_category_t category, uint8_t cap_len){
253     connection->error_code = 0;
254 
255     if (category == AVDTP_SERVICE_CATEGORY_INVALID_0 ||
256         (category == AVDTP_SERVICE_CATEGORY_INVALID_FF && connection->signaling_packet.signal_identifier == AVDTP_SI_RECONFIGURE)){
257         printf("    ERROR: BAD SERVICE CATEGORY %d\n", category);
258         connection->reject_service_category = category;
259         connection->error_code = BAD_SERV_CATEGORY;
260         return 1;
261     }
262 
263     if (connection->signaling_packet.signal_identifier == AVDTP_SI_RECONFIGURE){
264         if (category != AVDTP_CONTENT_PROTECTION && category != AVDTP_MEDIA_CODEC){
265             printf("    ERROR: REJECT CATEGORY, INVALID_CAPABILITIES\n");
266             connection->reject_service_category = category;
267             connection->error_code = INVALID_CAPABILITIES;
268             return 1;
269         }
270     }
271 
272     switch(category){
273         case AVDTP_MEDIA_TRANSPORT:
274             if (cap_len != 0){
275                 printf("    ERROR: REJECT CATEGORY, BAD_MEDIA_TRANSPORT\n");
276                 connection->reject_service_category = category;
277                 connection->error_code = BAD_MEDIA_TRANSPORT_FORMAT;
278                 return 1;
279             }
280             break;
281         case AVDTP_REPORTING:
282         case AVDTP_DELAY_REPORTING:
283             if (cap_len != 0){
284                 printf("    ERROR: REJECT CATEGORY, BAD_LENGTH\n");
285                 connection->reject_service_category = category;
286                 connection->error_code = BAD_LENGTH;
287                 return 1;
288             }
289             break;
290         case AVDTP_RECOVERY:
291             if (cap_len < 3){
292                 printf("    ERROR: REJECT CATEGORY, BAD_MEDIA_TRANSPORT\n");
293                 connection->reject_service_category = category;
294                 connection->error_code = BAD_RECOVERY_FORMAT;
295                 return 1;
296             }
297             break;
298         case AVDTP_CONTENT_PROTECTION:
299             if (cap_len < 2){
300                 printf("    ERROR: REJECT CATEGORY, BAD_CP_FORMAT\n");
301                 connection->reject_service_category = category;
302                 connection->error_code = BAD_CP_FORMAT;
303                 return 1;
304             }
305             break;
306         case AVDTP_HEADER_COMPRESSION:
307             break;
308         case AVDTP_MULTIPLEXING:
309             break;
310         case AVDTP_MEDIA_CODEC:
311             break;
312         default:
313             break;
314     }
315     return 0;
316 }
317 
318 uint16_t avdtp_unpack_service_capabilities(avdtp_connection_t * connection, avdtp_capabilities_t * caps, uint8_t * packet, uint16_t size){
319     if (size == 0) return 0;
320 
321     uint16_t registered_service_categories = 0;
322     int pos = 0;
323     int i;
324     avdtp_service_category_t category = (avdtp_service_category_t)packet[pos++];
325     uint8_t cap_len = packet[pos++];
326 
327     if (avdtp_unpack_service_capabilities_has_errors(connection, category, cap_len)) return 0;
328     int processed_cap_len = 0;
329     int rfa = 0;
330     //printf(" size %d, cat size %d\n", size, cap_len);
331 
332     while (pos < size){
333         if (cap_len > size - pos){
334             connection->reject_service_category = category;
335             connection->error_code = BAD_LENGTH;
336             return 0;
337         }
338         rfa = 0;
339         processed_cap_len = pos;
340         switch(category){
341             case AVDTP_RECOVERY:
342                 caps->recovery.recovery_type = packet[pos++];
343                 caps->recovery.maximum_recovery_window_size = packet[pos++];
344                 caps->recovery.maximum_number_media_packets = packet[pos++];
345                 break;
346             case AVDTP_CONTENT_PROTECTION:
347                 caps->content_protection.cp_type = big_endian_read_16(packet, pos);
348                 pos+=2;
349 
350                 caps->content_protection.cp_type_value_len = cap_len - 2;
351                 pos += caps->content_protection.cp_type_value_len;
352 
353                 // connection->reject_service_category = category;
354                 // connection->error_code = UNSUPPORTED_CONFIGURATION;
355                 // support for content protection goes here
356                 break;
357 
358             case AVDTP_HEADER_COMPRESSION:
359                 caps->header_compression.back_ch  = packet[pos] >> 7;
360                 caps->header_compression.media    = packet[pos] >> 6;
361                 caps->header_compression.recovery = packet[pos] >> 5;
362                 pos++;
363                 break;
364             case AVDTP_MULTIPLEXING:
365                 caps->multiplexing_mode.fragmentation = packet[pos++] >> 7;
366                 // read [tsid, tcid] for media, reporting. recovery respectively
367                 caps->multiplexing_mode.transport_identifiers_num = 3;
368                 for (i=0; i<caps->multiplexing_mode.transport_identifiers_num; i++){
369                     caps->multiplexing_mode.transport_session_identifiers[i] = packet[pos++] >> 7;
370                     caps->multiplexing_mode.tcid[i] = packet[pos++] >> 7;
371                 }
372                 break;
373             case AVDTP_MEDIA_CODEC:
374                 caps->media_codec.media_type = packet[pos++] >> 4;
375                 caps->media_codec.media_codec_type = packet[pos++];
376                 caps->media_codec.media_codec_information_len = cap_len - 2;
377                 caps->media_codec.media_codec_information = &packet[pos];
378                 pos += caps->media_codec.media_codec_information_len;
379                 break;
380             case AVDTP_MEDIA_TRANSPORT:
381             case AVDTP_REPORTING:
382             case AVDTP_DELAY_REPORTING:
383                 pos += cap_len;
384                 break;
385             default:
386                 pos += cap_len;
387                 rfa = 1;
388                 break;
389         }
390         processed_cap_len = pos - processed_cap_len;
391 
392         if (cap_len == processed_cap_len){
393             if (!rfa) {
394                 registered_service_categories = store_bit16(registered_service_categories, category, 1);
395             }
396             if (pos < size-2){
397                 //int old_pos = pos;
398                 category = (avdtp_service_category_t)packet[pos++];
399                 cap_len = packet[pos++];
400                 if (avdtp_unpack_service_capabilities_has_errors(connection, category, cap_len)) return 0;
401                 //printf("category %d, pos %d + 2 + %d -> %d\n", category, old_pos, cap_len, pos + cap_len);
402                 //printf_hexdump(packet+old_pos, size-old_pos);
403             }
404         }
405     }
406     return registered_service_categories;
407 }
408 
409 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){
410     if (signaling_packet->offset) return;
411     uint8_t pack_all_capabilities = 1;
412     signaling_packet->message_type = AVDTP_RESPONSE_ACCEPT_MSG;
413     int i;
414 
415     signaling_packet->size = 0;
416     memset(signaling_packet->command, 0 , sizeof(signaling_packet->command));
417 
418 
419     switch (identifier) {
420         case AVDTP_SI_GET_CAPABILITIES:
421             pack_all_capabilities = 0;
422             break;
423         case AVDTP_SI_GET_ALL_CAPABILITIES:
424             pack_all_capabilities = 1;
425             break;
426         case AVDTP_SI_SET_CONFIGURATION:
427             signaling_packet->command[signaling_packet->size++] = signaling_packet->acp_seid << 2;
428             signaling_packet->command[signaling_packet->size++] = signaling_packet->int_seid << 2;
429             signaling_packet->message_type = AVDTP_CMD_MSG;
430             break;
431         case AVDTP_SI_RECONFIGURE:
432             signaling_packet->command[signaling_packet->size++] = signaling_packet->acp_seid << 2;
433             signaling_packet->message_type = AVDTP_CMD_MSG;
434             break;
435         default:
436             log_error("avdtp_prepare_capabilities wrong identifier %d", identifier);
437             break;
438     }
439 
440     // printf("registered_service_categories: 0x%02x\n", registered_service_categories);
441 
442     // printf("command before packing:\n");
443     // printf_hexdump(signaling_packet->command, signaling_packet->size);
444     for (i = 1; i < 9; i++){
445         int registered_category = get_bit16(registered_service_categories, i);
446         if (!registered_category && (identifier == AVDTP_SI_SET_CONFIGURATION || identifier == AVDTP_SI_RECONFIGURE)){
447             // TODO: introduce bitmap of mandatory categories
448             if (i == 1){
449                 registered_category = 1;
450             }
451         }
452         if (registered_category){
453             // service category
454             // printf("pack service category: %d\n", i);
455             signaling_packet->command[signaling_packet->size++] = i;
456             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);
457         }
458     }
459     // printf("command after packing:\n");
460     // printf_hexdump(signaling_packet->command, signaling_packet->size);
461 
462     signaling_packet->signal_identifier = identifier;
463     signaling_packet->transaction_label = transaction_label;
464 }
465 
466 int avdtp_signaling_create_fragment(uint16_t cid, avdtp_signaling_packet_t * signaling_packet, uint8_t * out_buffer) {
467     int mtu = l2cap_get_remote_mtu_for_local_cid(cid);
468     // hack for test
469     // int mtu = 6;
470     int data_len = 0;
471 
472     uint16_t offset = signaling_packet->offset;
473     uint16_t pos = 1;
474     // printf(" avdtp_signaling_create_fragment offset %d, packet type %d\n",  signaling_packet->offset, signaling_packet->packet_type);
475 
476     if (offset == 0){
477         if (signaling_packet->size <= mtu - 2){
478             // printf(" AVDTP_SINGLE_PACKET\n");
479             signaling_packet->packet_type = AVDTP_SINGLE_PACKET;
480             out_buffer[pos++] = signaling_packet->signal_identifier;
481             data_len = signaling_packet->size;
482         } else {
483             signaling_packet->packet_type = AVDTP_START_PACKET;
484             out_buffer[pos++] = (mtu + signaling_packet->size)/ (mtu-1);
485             out_buffer[pos++] = signaling_packet->signal_identifier;
486             data_len = mtu - 3;
487             signaling_packet->offset = data_len;
488             // printf(" AVDTP_START_PACKET len %d, offset %d\n", signaling_packet->size, signaling_packet->offset);
489         }
490     } else {
491         int remaining_bytes = signaling_packet->size - offset;
492         if (remaining_bytes <= mtu - 1){
493             //signaling_packet->fragmentation = 1;
494             signaling_packet->packet_type = AVDTP_END_PACKET;
495             data_len = remaining_bytes;
496             signaling_packet->offset = 0;
497             // printf(" AVDTP_END_PACKET len %d, offset %d\n", signaling_packet->size, signaling_packet->offset);
498         } else{
499             signaling_packet->packet_type = AVDTP_CONTINUE_PACKET;
500             data_len = mtu - 1;
501             signaling_packet->offset += data_len;
502             // printf(" AVDTP_CONTINUE_PACKET len %d, offset %d\n", signaling_packet->size, signaling_packet->offset);
503         }
504     }
505     out_buffer[0] = avdtp_header(signaling_packet->transaction_label, signaling_packet->packet_type, signaling_packet->message_type);
506     memcpy(out_buffer+pos, signaling_packet->command + offset, data_len);
507     pos += data_len;
508     return pos;
509 }
510 
511 
512 void avdtp_signaling_emit_connection_established(btstack_packet_handler_t callback, uint16_t con_handle, bd_addr_t addr, uint8_t status){
513     if (!callback) return;
514     uint8_t event[12];
515     int pos = 0;
516     event[pos++] = HCI_EVENT_AVDTP_META;
517     event[pos++] = sizeof(event) - 2;
518     event[pos++] = AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED;
519     little_endian_store_16(event, pos, con_handle);
520     pos += 2;
521     reverse_bd_addr(addr,&event[pos]);
522     pos += 6;
523     event[pos++] = status;
524     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
525 }
526 
527 void avdtp_streaming_emit_connection_established(btstack_packet_handler_t callback, uint16_t con_handle, uint8_t status){
528     if (!callback) return;
529     uint8_t event[6];
530     int pos = 0;
531     event[pos++] = HCI_EVENT_AVDTP_META;
532     event[pos++] = sizeof(event) - 2;
533     event[pos++] = AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED;
534     little_endian_store_16(event, pos, con_handle);
535     pos += 2;
536     event[pos++] = status;
537     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
538 }
539 
540 void avdtp_signaling_emit_sep(btstack_packet_handler_t callback, uint16_t con_handle, avdtp_sep_t sep){
541     if (!callback) return;
542     uint8_t event[9];
543     int pos = 0;
544     event[pos++] = HCI_EVENT_AVDTP_META;
545     event[pos++] = sizeof(event) - 2;
546     event[pos++] = AVDTP_SUBEVENT_SIGNALING_SEP_FOUND;
547     little_endian_store_16(event, pos, con_handle);
548     pos += 2;
549     event[pos++] = sep.seid;
550     event[pos++] = sep.in_use;
551     event[pos++] = sep.media_type;
552     event[pos++] = sep.type;
553     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
554 }
555 
556 void avdtp_signaling_emit_accept(btstack_packet_handler_t callback, uint16_t con_handle, avdtp_signal_identifier_t identifier, uint8_t status){
557     if (!callback) return;
558     uint8_t event[7];
559     int pos = 0;
560     event[pos++] = HCI_EVENT_AVDTP_META;
561     event[pos++] = sizeof(event) - 2;
562     event[pos++] = AVDTP_SUBEVENT_SIGNALING_ACCEPT;
563     little_endian_store_16(event, pos, con_handle);
564     pos += 2;
565     event[pos++] = identifier;
566     event[pos++] = status;
567     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
568 }
569 
570 void avdtp_signaling_emit_reject(btstack_packet_handler_t callback, uint16_t con_handle, avdtp_signal_identifier_t identifier){
571     if (!callback) return;
572     uint8_t event[6];
573     int pos = 0;
574     event[pos++] = HCI_EVENT_AVDTP_META;
575     event[pos++] = sizeof(event) - 2;
576     event[pos++] = AVDTP_SUBEVENT_SIGNALING_REJECT;
577     little_endian_store_16(event, pos, con_handle);
578     pos += 2;
579     event[pos++] = identifier;
580     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
581 }
582 
583 void avdtp_signaling_emit_general_reject(btstack_packet_handler_t callback, uint16_t con_handle, avdtp_signal_identifier_t identifier){
584     if (!callback) return;
585     uint8_t event[6];
586     int pos = 0;
587     event[pos++] = HCI_EVENT_AVDTP_META;
588     event[pos++] = sizeof(event) - 2;
589     event[pos++] = AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT;
590     little_endian_store_16(event, pos, con_handle);
591     pos += 2;
592     event[pos++] = identifier;
593     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
594 }
595 
596 void avdtp_signaling_emit_media_codec_sbc_capability(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
597     if (!callback) return;
598     uint8_t event[13];
599     int pos = 0;
600     event[pos++] = HCI_EVENT_AVDTP_META;
601     event[pos++] = sizeof(event) - 2;
602     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY;
603     little_endian_store_16(event, pos, con_handle);
604     pos += 2;
605     event[pos++] = media_codec.media_type;
606     event[pos++] = media_codec.media_codec_information[0] >> 4;
607     event[pos++] = media_codec.media_codec_information[0] & 0x0F;
608     event[pos++] = media_codec.media_codec_information[1] >> 4;
609     event[pos++] = (media_codec.media_codec_information[1] & 0x0F) >> 2;
610     event[pos++] = media_codec.media_codec_information[1] & 0x03;
611     event[pos++] = media_codec.media_codec_information[2];
612     event[pos++] = media_codec.media_codec_information[3];
613     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
614 }
615 
616 void avdtp_signaling_emit_media_codec_other_capability(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
617     if (!callback) return;
618         uint8_t event[109];
619     int pos = 0;
620     event[pos++] = HCI_EVENT_AVDTP_META;
621     event[pos++] = sizeof(event) - 2;
622     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY;
623     little_endian_store_16(event, pos, con_handle);
624     pos += 2;
625     event[pos++] = media_codec.media_type;
626     little_endian_store_16(event, pos, media_codec.media_codec_type);
627     pos += 2;
628     little_endian_store_16(event, pos, media_codec.media_codec_information_len);
629     pos += 2;
630     if (media_codec.media_codec_information_len < 100){
631         memcpy(event+pos, media_codec.media_codec_information, media_codec.media_codec_information_len);
632     } else {
633         memcpy(event+pos, media_codec.media_codec_information, 100);
634     }
635     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
636 }
637 
638 static inline void avdtp_signaling_emit_media_codec_sbc(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec, uint8_t reconfigure){
639     if (!callback) return;
640     uint8_t event[14+2];
641     int pos = 0;
642     event[pos++] = HCI_EVENT_AVDTP_META;
643     event[pos++] = sizeof(event) - 2;
644 
645     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION;
646     little_endian_store_16(event, pos, con_handle);
647     pos += 2;
648     event[pos++] = reconfigure;
649 
650     uint8_t num_channels = 0;
651     uint16_t sampling_frequency = 0;
652     uint8_t subbands = 0;
653     uint8_t block_length = 0;
654 
655     uint8_t sampling_frequency_bitmap = media_codec.media_codec_information[0] >> 4;
656     uint8_t channel_mode_bitmap = media_codec.media_codec_information[0] & 0x0F;
657     uint8_t block_length_bitmap = media_codec.media_codec_information[1] >> 4;
658     uint8_t subbands_bitmap = (media_codec.media_codec_information[1] & 0x0F) >> 2;
659 
660     if (channel_mode_bitmap & AVDTP_SBC_MONO){
661         num_channels = 1;
662     }
663     if ( (channel_mode_bitmap & AVDTP_SBC_JOINT_STEREO) ||
664          (channel_mode_bitmap & AVDTP_SBC_STEREO) ||
665          (channel_mode_bitmap & AVDTP_SBC_DUAL_CHANNEL) ){
666         num_channels = 2;
667     }
668 
669     if (sampling_frequency_bitmap & AVDTP_SBC_16000){
670         sampling_frequency = 16000;
671     }
672     if (sampling_frequency_bitmap & AVDTP_SBC_32000){
673         sampling_frequency = 32000;
674     }
675     if (sampling_frequency_bitmap & AVDTP_SBC_44100){
676         sampling_frequency = 44100;
677     }
678     if (sampling_frequency_bitmap & AVDTP_SBC_48000){
679         sampling_frequency = 48000;
680     }
681 
682     if (subbands_bitmap & AVDTP_SBC_SUBBANDS_4){
683         subbands = 4;
684     }
685     if (subbands_bitmap & AVDTP_SBC_SUBBANDS_8){
686         subbands = 8;
687     }
688 
689     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_4){
690         block_length = 4;
691     }
692     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_8){
693         block_length = 8;
694     }
695     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_12){
696         block_length = 12;
697     }
698     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_16){
699         block_length = 16;
700     }
701 
702     event[pos++] = media_codec.media_type;
703     little_endian_store_16(event, pos, sampling_frequency);
704     pos += 2;
705 
706     event[pos++] = channel_mode_bitmap;
707     event[pos++] = num_channels;
708     event[pos++] = block_length;
709     event[pos++] = subbands;
710     event[pos++] = media_codec.media_codec_information[1] & 0x03;
711     event[pos++] = media_codec.media_codec_information[2];
712     event[pos++] = media_codec.media_codec_information[3];
713     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
714 }
715 
716 void avdtp_signaling_emit_media_codec_sbc_configuration(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
717     if (!callback) return;
718     avdtp_signaling_emit_media_codec_sbc(callback, con_handle, media_codec, 0);
719 }
720 
721 void avdtp_signaling_emit_media_codec_sbc_reconfiguration(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
722     if (!callback) return;
723     avdtp_signaling_emit_media_codec_sbc(callback, con_handle, media_codec, 1);
724 }
725 
726 static inline void avdtp_signaling_emit_media_codec_other(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec, uint8_t reconfigure){
727     uint8_t event[110];
728     int pos = 0;
729     event[pos++] = HCI_EVENT_AVDTP_META;
730     event[pos++] = sizeof(event) - 2;
731     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION;
732     little_endian_store_16(event, pos, con_handle);
733     pos += 2;
734 
735     event[pos++] = reconfigure;
736 
737     event[pos++] = media_codec.media_type;
738     little_endian_store_16(event, pos, media_codec.media_codec_type);
739     pos += 2;
740     little_endian_store_16(event, pos, media_codec.media_codec_information_len);
741     pos += 2;
742 
743     if (media_codec.media_codec_information_len < 100){
744         memcpy(event+pos, media_codec.media_codec_information, media_codec.media_codec_information_len);
745     } else {
746         memcpy(event+pos, media_codec.media_codec_information, 100);
747     }
748     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
749 }
750 
751 void avdtp_signaling_emit_media_codec_other_configuration(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
752     if (!callback) return;
753     avdtp_signaling_emit_media_codec_other(callback, con_handle, media_codec, 0);
754 }
755 
756 void avdtp_signaling_emit_media_codec_other_reconfiguration(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
757     if (!callback) return;
758     avdtp_signaling_emit_media_codec_other(callback, con_handle, media_codec, 1);
759 }
760 
761 
762 void avdtp_request_can_send_now_acceptor(avdtp_connection_t * connection, uint16_t l2cap_cid){
763     connection->wait_to_send_acceptor = 1;
764     l2cap_request_can_send_now_event(l2cap_cid);
765 }
766 void avdtp_request_can_send_now_initiator(avdtp_connection_t * connection, uint16_t l2cap_cid){
767     connection->wait_to_send_initiator = 1;
768     l2cap_request_can_send_now_event(l2cap_cid);
769 }
770 void avdtp_request_can_send_now_self(avdtp_connection_t * connection, uint16_t l2cap_cid){
771     connection->wait_to_send_self = 1;
772     l2cap_request_can_send_now_event(l2cap_cid);
773 }
774 
775 uint8_t avdtp_get_index_of_remote_stream_endpoint_with_seid(avdtp_stream_endpoint_t * stream_endpoint, uint16_t seid){
776     if (stream_endpoint->remote_seps[stream_endpoint->remote_sep_index].seid == seid){
777         return stream_endpoint->remote_sep_index;
778     }
779     int i;
780     for (i=0; i < stream_endpoint->remote_seps_num; i++){
781         if (stream_endpoint->remote_seps[i].seid == seid){
782             return i;
783         }
784     }
785     return 0xFF;
786 }
787