xref: /btstack/src/classic/avdtp_util.c (revision ab2c6ae4b737d5e801d3defe4117331eb244ebb7)
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 = 0;
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     stream_endpoint->remote_sep_index = 0;
66 }
67 
68 avdtp_stream_endpoint_t * avdtp_stream_endpoint_for_seid(uint16_t seid, avdtp_context_t * context){
69     btstack_linked_list_iterator_t it;
70     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
71     while (btstack_linked_list_iterator_has_next(&it)){
72         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
73         if (stream_endpoint->sep.seid == seid){
74             return stream_endpoint;
75         }
76     }
77     return NULL;
78 }
79 
80 avdtp_connection_t * avdtp_connection_for_bd_addr(bd_addr_t addr, avdtp_context_t * context){
81     btstack_linked_list_iterator_t it;
82     btstack_linked_list_iterator_init(&it, &context->connections);
83     while (btstack_linked_list_iterator_has_next(&it)){
84         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
85         if (memcmp(addr, connection->remote_addr, 6) != 0) continue;
86         return connection;
87     }
88     return NULL;
89 }
90 
91 avdtp_connection_t * avdtp_connection_for_con_handle(hci_con_handle_t con_handle, avdtp_context_t * context){
92     btstack_linked_list_iterator_t it;
93     btstack_linked_list_iterator_init(&it, &context->connections);
94     while (btstack_linked_list_iterator_has_next(&it)){
95         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
96         if (connection->con_handle != con_handle) continue;
97         return connection;
98     }
99     return NULL;
100 }
101 
102 avdtp_connection_t * avdtp_connection_for_l2cap_signaling_cid(uint16_t l2cap_cid, avdtp_context_t * context){
103     btstack_linked_list_iterator_t it;
104     btstack_linked_list_iterator_init(&it, &context->connections);
105     while (btstack_linked_list_iterator_has_next(&it)){
106         avdtp_connection_t * connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
107         if (connection->l2cap_signaling_cid != l2cap_cid) continue;
108         return connection;
109     }
110     return NULL;
111 }
112 
113 avdtp_stream_endpoint_t * avdtp_stream_endpoint_for_l2cap_cid(uint16_t l2cap_cid, avdtp_context_t * context){
114     btstack_linked_list_iterator_t it;
115     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
116     while (btstack_linked_list_iterator_has_next(&it)){
117         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
118         if (stream_endpoint->l2cap_media_cid == l2cap_cid){
119             return stream_endpoint;
120         }
121         if (stream_endpoint->l2cap_reporting_cid == l2cap_cid){
122             return stream_endpoint;
123         }
124         if (stream_endpoint->l2cap_recovery_cid == l2cap_cid){
125             return stream_endpoint;
126         }
127     }
128     return NULL;
129 }
130 
131 avdtp_stream_endpoint_t * avdtp_stream_endpoint_with_seid(uint8_t seid, avdtp_context_t * context){
132     btstack_linked_list_iterator_t it;
133     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
134     while (btstack_linked_list_iterator_has_next(&it)){
135         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
136         if (stream_endpoint->sep.seid == seid){
137             return stream_endpoint;
138         }
139     }
140     return NULL;
141 }
142 
143 avdtp_stream_endpoint_t * avdtp_stream_endpoint_associated_with_acp_seid(uint16_t acp_seid, avdtp_context_t * context){
144     btstack_linked_list_iterator_t it;
145     btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
146     while (btstack_linked_list_iterator_has_next(&it)){
147         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
148         if (stream_endpoint->remote_sep_index >= 0 && stream_endpoint->remote_sep_index < MAX_NUM_SEPS){
149             if (stream_endpoint->remote_seps[stream_endpoint->remote_sep_index].seid == acp_seid){
150                 return stream_endpoint;
151             }
152         }
153     }
154     return NULL;
155 }
156 
157 int get_bit16(uint16_t bitmap, int position){
158     return (bitmap >> position) & 1;
159 }
160 
161 uint8_t store_bit16(uint16_t bitmap, int position, uint8_t value){
162     if (value){
163         bitmap |= 1 << position;
164     } else {
165         bitmap &= ~ (1 << position);
166     }
167     return bitmap;
168 }
169 
170 int avdtp_read_signaling_header(avdtp_signaling_packet_t * signaling_header, uint8_t * packet, uint16_t size){
171     int pos = 0;
172     if (size < 2) return pos;
173     signaling_header->transaction_label = packet[pos] >> 4;
174     signaling_header->packet_type = (avdtp_packet_type_t)((packet[pos] >> 2) & 0x03);
175     signaling_header->message_type = (avdtp_message_type_t) (packet[pos] & 0x03);
176     pos++;
177     memset(signaling_header->command, 0, sizeof(signaling_header->command));
178     switch (signaling_header->packet_type){
179         case AVDTP_SINGLE_PACKET:
180             signaling_header->num_packets = 0;
181             signaling_header->offset = 0;
182             signaling_header->size = 0;
183             break;
184         case AVDTP_END_PACKET:
185             signaling_header->num_packets = 0;
186             break;
187         case AVDTP_START_PACKET:
188             signaling_header->num_packets = packet[pos++];
189             signaling_header->size = 0;
190             signaling_header->offset = 0;
191             break;
192         case AVDTP_CONTINUE_PACKET:
193             if (signaling_header->num_packets <= 0) {
194                 printf("    ERROR: wrong num fragmented packets\n");
195                 break;
196             }
197             signaling_header->num_packets--;
198             break;
199     }
200     signaling_header->signal_identifier = packet[pos++] & 0x3f;
201     return pos;
202 }
203 
204 int avdtp_pack_service_capabilities(uint8_t * buffer, int size, avdtp_capabilities_t caps, avdtp_service_category_t category, uint8_t pack_all_capabilities){
205     UNUSED(size);
206 
207     int i;
208     // pos = 0 reserved for length
209     int pos = 1;
210     switch(category){
211         case AVDTP_MEDIA_TRANSPORT:
212         case AVDTP_REPORTING:
213             break;
214         case AVDTP_DELAY_REPORTING:
215             if (!pack_all_capabilities) break;
216             break;
217         case AVDTP_RECOVERY:
218             buffer[pos++] = caps.recovery.recovery_type; // 0x01=RFC2733
219             buffer[pos++] = caps.recovery.maximum_recovery_window_size;
220             buffer[pos++] = caps.recovery.maximum_number_media_packets;
221             break;
222         case AVDTP_CONTENT_PROTECTION:
223             buffer[pos++] = caps.content_protection.cp_type_value_len + 2;
224             big_endian_store_16(buffer, pos, caps.content_protection.cp_type);
225             pos += 2;
226             memcpy(buffer+pos, caps.content_protection.cp_type_value, caps.content_protection.cp_type_value_len);
227             break;
228         case AVDTP_HEADER_COMPRESSION:
229             buffer[pos++] = (caps.header_compression.back_ch << 7) | (caps.header_compression.media << 6) | (caps.header_compression.recovery << 5);
230             break;
231         case AVDTP_MULTIPLEXING:
232             buffer[pos++] = caps.multiplexing_mode.fragmentation << 7;
233             for (i=0; i<caps.multiplexing_mode.transport_identifiers_num; i++){
234                 buffer[pos++] = caps.multiplexing_mode.transport_session_identifiers[i] << 7;
235                 buffer[pos++] = caps.multiplexing_mode.tcid[i] << 7;
236                 // media, reporting. recovery
237             }
238             break;
239         case AVDTP_MEDIA_CODEC:
240             buffer[pos++] = ((uint8_t)caps.media_codec.media_type) << 4;
241             buffer[pos++] = (uint8_t)caps.media_codec.media_codec_type;
242             for (i = 0; i<caps.media_codec.media_codec_information_len; i++){
243                 buffer[pos++] = caps.media_codec.media_codec_information[i];
244             }
245             break;
246         default:
247             break;
248     }
249     buffer[0] = pos - 1; // length
250     return pos;
251 }
252 
253 static int avdtp_unpack_service_capabilities_has_errors(avdtp_connection_t * connection, avdtp_service_category_t category, uint8_t cap_len){
254     connection->error_code = 0;
255 
256     if (category == AVDTP_SERVICE_CATEGORY_INVALID_0 ||
257         (category == AVDTP_SERVICE_CATEGORY_INVALID_FF && connection->signaling_packet.signal_identifier == AVDTP_SI_RECONFIGURE)){
258         printf("    ERROR: BAD SERVICE CATEGORY %d\n", category);
259         connection->reject_service_category = category;
260         connection->error_code = BAD_SERV_CATEGORY;
261         return 1;
262     }
263 
264     if (connection->signaling_packet.signal_identifier == AVDTP_SI_RECONFIGURE){
265         if (category != AVDTP_CONTENT_PROTECTION && category != AVDTP_MEDIA_CODEC){
266             printf("    ERROR: REJECT CATEGORY, INVALID_CAPABILITIES\n");
267             connection->reject_service_category = category;
268             connection->error_code = INVALID_CAPABILITIES;
269             return 1;
270         }
271     }
272 
273     switch(category){
274         case AVDTP_MEDIA_TRANSPORT:
275             if (cap_len != 0){
276                 printf("    ERROR: REJECT CATEGORY, BAD_MEDIA_TRANSPORT\n");
277                 connection->reject_service_category = category;
278                 connection->error_code = BAD_MEDIA_TRANSPORT_FORMAT;
279                 return 1;
280             }
281             break;
282         case AVDTP_REPORTING:
283         case AVDTP_DELAY_REPORTING:
284             if (cap_len != 0){
285                 printf("    ERROR: REJECT CATEGORY, BAD_LENGTH\n");
286                 connection->reject_service_category = category;
287                 connection->error_code = BAD_LENGTH;
288                 return 1;
289             }
290             break;
291         case AVDTP_RECOVERY:
292             if (cap_len < 3){
293                 printf("    ERROR: REJECT CATEGORY, BAD_MEDIA_TRANSPORT\n");
294                 connection->reject_service_category = category;
295                 connection->error_code = BAD_RECOVERY_FORMAT;
296                 return 1;
297             }
298             break;
299         case AVDTP_CONTENT_PROTECTION:
300             if (cap_len < 2){
301                 printf("    ERROR: REJECT CATEGORY, BAD_CP_FORMAT\n");
302                 connection->reject_service_category = category;
303                 connection->error_code = BAD_CP_FORMAT;
304                 return 1;
305             }
306             break;
307         case AVDTP_HEADER_COMPRESSION:
308             break;
309         case AVDTP_MULTIPLEXING:
310             break;
311         case AVDTP_MEDIA_CODEC:
312             break;
313         default:
314             break;
315     }
316     return 0;
317 }
318 
319 uint16_t avdtp_unpack_service_capabilities(avdtp_connection_t * connection, avdtp_capabilities_t * caps, uint8_t * packet, uint16_t size){
320     if (size == 0) return 0;
321 
322     uint16_t registered_service_categories = 0;
323     int pos = 0;
324     int i;
325     avdtp_service_category_t category = (avdtp_service_category_t)packet[pos++];
326     uint8_t cap_len = packet[pos++];
327 
328     if (avdtp_unpack_service_capabilities_has_errors(connection, category, cap_len)) return 0;
329     int processed_cap_len = 0;
330     int rfa = 0;
331     //printf(" size %d, cat size %d\n", size, cap_len);
332 
333     while (pos < size){
334         if (cap_len > size - pos){
335             connection->reject_service_category = category;
336             connection->error_code = BAD_LENGTH;
337             return 0;
338         }
339         rfa = 0;
340         processed_cap_len = pos;
341         switch(category){
342             case AVDTP_RECOVERY:
343                 caps->recovery.recovery_type = packet[pos++];
344                 caps->recovery.maximum_recovery_window_size = packet[pos++];
345                 caps->recovery.maximum_number_media_packets = packet[pos++];
346                 break;
347             case AVDTP_CONTENT_PROTECTION:
348                 caps->content_protection.cp_type = big_endian_read_16(packet, pos);
349                 pos+=2;
350 
351                 caps->content_protection.cp_type_value_len = cap_len - 2;
352                 pos += caps->content_protection.cp_type_value_len;
353 
354                 // connection->reject_service_category = category;
355                 // connection->error_code = UNSUPPORTED_CONFIGURATION;
356                 // support for content protection goes here
357                 break;
358 
359             case AVDTP_HEADER_COMPRESSION:
360                 caps->header_compression.back_ch  = packet[pos] >> 7;
361                 caps->header_compression.media    = packet[pos] >> 6;
362                 caps->header_compression.recovery = packet[pos] >> 5;
363                 pos++;
364                 break;
365             case AVDTP_MULTIPLEXING:
366                 caps->multiplexing_mode.fragmentation = packet[pos++] >> 7;
367                 // read [tsid, tcid] for media, reporting. recovery respectively
368                 caps->multiplexing_mode.transport_identifiers_num = 3;
369                 for (i=0; i<caps->multiplexing_mode.transport_identifiers_num; i++){
370                     caps->multiplexing_mode.transport_session_identifiers[i] = packet[pos++] >> 7;
371                     caps->multiplexing_mode.tcid[i] = packet[pos++] >> 7;
372                 }
373                 break;
374             case AVDTP_MEDIA_CODEC:
375                 caps->media_codec.media_type = packet[pos++] >> 4;
376                 caps->media_codec.media_codec_type = packet[pos++];
377                 caps->media_codec.media_codec_information_len = cap_len - 2;
378                 caps->media_codec.media_codec_information = &packet[pos];
379                 pos += caps->media_codec.media_codec_information_len;
380                 break;
381             case AVDTP_MEDIA_TRANSPORT:
382             case AVDTP_REPORTING:
383             case AVDTP_DELAY_REPORTING:
384                 pos += cap_len;
385                 break;
386             default:
387                 pos += cap_len;
388                 rfa = 1;
389                 break;
390         }
391         processed_cap_len = pos - processed_cap_len;
392 
393         if (cap_len == processed_cap_len){
394             if (!rfa) {
395                 registered_service_categories = store_bit16(registered_service_categories, category, 1);
396             }
397             if (pos < size-2){
398                 //int old_pos = pos;
399                 category = (avdtp_service_category_t)packet[pos++];
400                 cap_len = packet[pos++];
401                 if (avdtp_unpack_service_capabilities_has_errors(connection, category, cap_len)) return 0;
402                 //printf("category %d, pos %d + 2 + %d -> %d\n", category, old_pos, cap_len, pos + cap_len);
403                 //printf_hexdump(packet+old_pos, size-old_pos);
404             }
405         }
406     }
407     return registered_service_categories;
408 }
409 
410 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){
411     if (signaling_packet->offset) return;
412     uint8_t pack_all_capabilities = 1;
413     signaling_packet->message_type = AVDTP_RESPONSE_ACCEPT_MSG;
414     int i;
415 
416     signaling_packet->size = 0;
417     memset(signaling_packet->command, 0 , sizeof(signaling_packet->command));
418 
419 
420     switch (identifier) {
421         case AVDTP_SI_GET_CAPABILITIES:
422             pack_all_capabilities = 0;
423             break;
424         case AVDTP_SI_GET_ALL_CAPABILITIES:
425             pack_all_capabilities = 1;
426             break;
427         case AVDTP_SI_SET_CONFIGURATION:
428             signaling_packet->command[signaling_packet->size++] = signaling_packet->acp_seid << 2;
429             signaling_packet->command[signaling_packet->size++] = signaling_packet->int_seid << 2;
430             signaling_packet->message_type = AVDTP_CMD_MSG;
431             break;
432         case AVDTP_SI_RECONFIGURE:
433             signaling_packet->command[signaling_packet->size++] = signaling_packet->acp_seid << 2;
434             signaling_packet->message_type = AVDTP_CMD_MSG;
435             break;
436         default:
437             log_error("avdtp_prepare_capabilities wrong identifier %d", identifier);
438             break;
439     }
440 
441     // printf("registered_service_categories: 0x%02x\n", registered_service_categories);
442 
443     // printf("command before packing:\n");
444     // printf_hexdump(signaling_packet->command, signaling_packet->size);
445     for (i = 1; i < 9; i++){
446         int registered_category = get_bit16(registered_service_categories, i);
447         if (!registered_category && (identifier == AVDTP_SI_SET_CONFIGURATION || identifier == AVDTP_SI_RECONFIGURE)){
448             // TODO: introduce bitmap of mandatory categories
449             if (i == 1){
450                 registered_category = 1;
451             }
452         }
453         if (registered_category){
454             // service category
455             // printf("pack service category: %d\n", i);
456             signaling_packet->command[signaling_packet->size++] = i;
457             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);
458         }
459     }
460     // printf("command after packing:\n");
461     // printf_hexdump(signaling_packet->command, signaling_packet->size);
462 
463     signaling_packet->signal_identifier = identifier;
464     signaling_packet->transaction_label = transaction_label;
465 }
466 
467 int avdtp_signaling_create_fragment(uint16_t cid, avdtp_signaling_packet_t * signaling_packet, uint8_t * out_buffer) {
468     int mtu = l2cap_get_remote_mtu_for_local_cid(cid);
469     // hack for test
470     // int mtu = 6;
471     int data_len = 0;
472 
473     uint16_t offset = signaling_packet->offset;
474     uint16_t pos = 1;
475     // printf(" avdtp_signaling_create_fragment offset %d, packet type %d\n",  signaling_packet->offset, signaling_packet->packet_type);
476 
477     if (offset == 0){
478         if (signaling_packet->size <= mtu - 2){
479             // printf(" AVDTP_SINGLE_PACKET\n");
480             signaling_packet->packet_type = AVDTP_SINGLE_PACKET;
481             out_buffer[pos++] = signaling_packet->signal_identifier;
482             data_len = signaling_packet->size;
483         } else {
484             signaling_packet->packet_type = AVDTP_START_PACKET;
485             out_buffer[pos++] = (mtu + signaling_packet->size)/ (mtu-1);
486             out_buffer[pos++] = signaling_packet->signal_identifier;
487             data_len = mtu - 3;
488             signaling_packet->offset = data_len;
489             // printf(" AVDTP_START_PACKET len %d, offset %d\n", signaling_packet->size, signaling_packet->offset);
490         }
491     } else {
492         int remaining_bytes = signaling_packet->size - offset;
493         if (remaining_bytes <= mtu - 1){
494             //signaling_packet->fragmentation = 1;
495             signaling_packet->packet_type = AVDTP_END_PACKET;
496             data_len = remaining_bytes;
497             signaling_packet->offset = 0;
498             // printf(" AVDTP_END_PACKET len %d, offset %d\n", signaling_packet->size, signaling_packet->offset);
499         } else{
500             signaling_packet->packet_type = AVDTP_CONTINUE_PACKET;
501             data_len = mtu - 1;
502             signaling_packet->offset += data_len;
503             // printf(" AVDTP_CONTINUE_PACKET len %d, offset %d\n", signaling_packet->size, signaling_packet->offset);
504         }
505     }
506     out_buffer[0] = avdtp_header(signaling_packet->transaction_label, signaling_packet->packet_type, signaling_packet->message_type);
507     memcpy(out_buffer+pos, signaling_packet->command + offset, data_len);
508     pos += data_len;
509     return pos;
510 }
511 
512 
513 void avdtp_signaling_emit_connection_established(btstack_packet_handler_t callback, uint16_t con_handle, bd_addr_t addr, uint8_t status){
514     if (!callback) return;
515     uint8_t event[12];
516     int pos = 0;
517     event[pos++] = HCI_EVENT_AVDTP_META;
518     event[pos++] = sizeof(event) - 2;
519     event[pos++] = AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED;
520     little_endian_store_16(event, pos, con_handle);
521     pos += 2;
522     reverse_bd_addr(addr,&event[pos]);
523     pos += 6;
524     event[pos++] = status;
525     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
526 }
527 
528 void avdtp_streaming_emit_connection_established(btstack_packet_handler_t callback, uint16_t con_handle, uint8_t status){
529     if (!callback) return;
530     uint8_t event[6];
531     int pos = 0;
532     event[pos++] = HCI_EVENT_AVDTP_META;
533     event[pos++] = sizeof(event) - 2;
534     event[pos++] = AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED;
535     little_endian_store_16(event, pos, con_handle);
536     pos += 2;
537     event[pos++] = status;
538     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
539 }
540 
541 void avdtp_signaling_emit_sep(btstack_packet_handler_t callback, uint16_t con_handle, avdtp_sep_t sep){
542     if (!callback) return;
543     uint8_t event[9];
544     int pos = 0;
545     event[pos++] = HCI_EVENT_AVDTP_META;
546     event[pos++] = sizeof(event) - 2;
547     event[pos++] = AVDTP_SUBEVENT_SIGNALING_SEP_FOUND;
548     little_endian_store_16(event, pos, con_handle);
549     pos += 2;
550     event[pos++] = sep.seid;
551     event[pos++] = sep.in_use;
552     event[pos++] = sep.media_type;
553     event[pos++] = sep.type;
554     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
555 }
556 
557 void avdtp_signaling_emit_accept(btstack_packet_handler_t callback, uint16_t con_handle, avdtp_signal_identifier_t identifier, uint8_t status){
558     if (!callback) return;
559     uint8_t event[7];
560     int pos = 0;
561     event[pos++] = HCI_EVENT_AVDTP_META;
562     event[pos++] = sizeof(event) - 2;
563     event[pos++] = AVDTP_SUBEVENT_SIGNALING_ACCEPT;
564     little_endian_store_16(event, pos, con_handle);
565     pos += 2;
566     event[pos++] = identifier;
567     event[pos++] = status;
568     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
569 }
570 
571 void avdtp_signaling_emit_reject(btstack_packet_handler_t callback, uint16_t con_handle, avdtp_signal_identifier_t identifier){
572     if (!callback) return;
573     uint8_t event[6];
574     int pos = 0;
575     event[pos++] = HCI_EVENT_AVDTP_META;
576     event[pos++] = sizeof(event) - 2;
577     event[pos++] = AVDTP_SUBEVENT_SIGNALING_REJECT;
578     little_endian_store_16(event, pos, con_handle);
579     pos += 2;
580     event[pos++] = identifier;
581     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
582 }
583 
584 void avdtp_signaling_emit_general_reject(btstack_packet_handler_t callback, uint16_t con_handle, avdtp_signal_identifier_t identifier){
585     if (!callback) return;
586     uint8_t event[6];
587     int pos = 0;
588     event[pos++] = HCI_EVENT_AVDTP_META;
589     event[pos++] = sizeof(event) - 2;
590     event[pos++] = AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT;
591     little_endian_store_16(event, pos, con_handle);
592     pos += 2;
593     event[pos++] = identifier;
594     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
595 }
596 
597 void avdtp_signaling_emit_media_codec_sbc_capability(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
598     if (!callback) return;
599     uint8_t event[13];
600     int pos = 0;
601     event[pos++] = HCI_EVENT_AVDTP_META;
602     event[pos++] = sizeof(event) - 2;
603     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY;
604     little_endian_store_16(event, pos, con_handle);
605     pos += 2;
606     event[pos++] = media_codec.media_type;
607     event[pos++] = media_codec.media_codec_information[0] >> 4;
608     event[pos++] = media_codec.media_codec_information[0] & 0x0F;
609     event[pos++] = media_codec.media_codec_information[1] >> 4;
610     event[pos++] = (media_codec.media_codec_information[1] & 0x0F) >> 2;
611     event[pos++] = media_codec.media_codec_information[1] & 0x03;
612     event[pos++] = media_codec.media_codec_information[2];
613     event[pos++] = media_codec.media_codec_information[3];
614     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
615 }
616 
617 void avdtp_signaling_emit_media_codec_other_capability(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
618     if (!callback) return;
619         uint8_t event[109];
620     int pos = 0;
621     event[pos++] = HCI_EVENT_AVDTP_META;
622     event[pos++] = sizeof(event) - 2;
623     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY;
624     little_endian_store_16(event, pos, con_handle);
625     pos += 2;
626     event[pos++] = media_codec.media_type;
627     little_endian_store_16(event, pos, media_codec.media_codec_type);
628     pos += 2;
629     little_endian_store_16(event, pos, media_codec.media_codec_information_len);
630     pos += 2;
631     if (media_codec.media_codec_information_len < 100){
632         memcpy(event+pos, media_codec.media_codec_information, media_codec.media_codec_information_len);
633     } else {
634         memcpy(event+pos, media_codec.media_codec_information, 100);
635     }
636     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
637 }
638 
639 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){
640     if (!callback) return;
641     uint8_t event[14+2];
642     int pos = 0;
643     event[pos++] = HCI_EVENT_AVDTP_META;
644     event[pos++] = sizeof(event) - 2;
645 
646     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION;
647     little_endian_store_16(event, pos, con_handle);
648     pos += 2;
649     event[pos++] = reconfigure;
650 
651     uint8_t num_channels = 0;
652     uint16_t sampling_frequency = 0;
653     uint8_t subbands = 0;
654     uint8_t block_length = 0;
655 
656     uint8_t sampling_frequency_bitmap = media_codec.media_codec_information[0] >> 4;
657     uint8_t channel_mode_bitmap = media_codec.media_codec_information[0] & 0x0F;
658     uint8_t block_length_bitmap = media_codec.media_codec_information[1] >> 4;
659     uint8_t subbands_bitmap = (media_codec.media_codec_information[1] & 0x0F) >> 2;
660 
661     if (channel_mode_bitmap & AVDTP_SBC_MONO){
662         num_channels = 1;
663     }
664     if ( (channel_mode_bitmap & AVDTP_SBC_JOINT_STEREO) ||
665          (channel_mode_bitmap & AVDTP_SBC_STEREO) ||
666          (channel_mode_bitmap & AVDTP_SBC_DUAL_CHANNEL) ){
667         num_channels = 2;
668     }
669 
670     if (sampling_frequency_bitmap & AVDTP_SBC_16000){
671         sampling_frequency = 16000;
672     }
673     if (sampling_frequency_bitmap & AVDTP_SBC_32000){
674         sampling_frequency = 32000;
675     }
676     if (sampling_frequency_bitmap & AVDTP_SBC_44100){
677         sampling_frequency = 44100;
678     }
679     if (sampling_frequency_bitmap & AVDTP_SBC_48000){
680         sampling_frequency = 48000;
681     }
682 
683     if (subbands_bitmap & AVDTP_SBC_SUBBANDS_4){
684         subbands = 4;
685     }
686     if (subbands_bitmap & AVDTP_SBC_SUBBANDS_8){
687         subbands = 8;
688     }
689 
690     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_4){
691         block_length = 4;
692     }
693     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_8){
694         block_length = 8;
695     }
696     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_12){
697         block_length = 12;
698     }
699     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_16){
700         block_length = 16;
701     }
702 
703     event[pos++] = media_codec.media_type;
704     little_endian_store_16(event, pos, sampling_frequency);
705     pos += 2;
706 
707     event[pos++] = channel_mode_bitmap;
708     event[pos++] = num_channels;
709     event[pos++] = block_length;
710     event[pos++] = subbands;
711     event[pos++] = media_codec.media_codec_information[1] & 0x03;
712     event[pos++] = media_codec.media_codec_information[2];
713     event[pos++] = media_codec.media_codec_information[3];
714     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
715 }
716 
717 void avdtp_signaling_emit_media_codec_sbc_configuration(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
718     if (!callback) return;
719     avdtp_signaling_emit_media_codec_sbc(callback, con_handle, media_codec, 0);
720 }
721 
722 void avdtp_signaling_emit_media_codec_sbc_reconfiguration(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
723     if (!callback) return;
724     avdtp_signaling_emit_media_codec_sbc(callback, con_handle, media_codec, 1);
725 }
726 
727 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){
728     uint8_t event[110];
729     int pos = 0;
730     event[pos++] = HCI_EVENT_AVDTP_META;
731     event[pos++] = sizeof(event) - 2;
732     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION;
733     little_endian_store_16(event, pos, con_handle);
734     pos += 2;
735 
736     event[pos++] = reconfigure;
737 
738     event[pos++] = media_codec.media_type;
739     little_endian_store_16(event, pos, media_codec.media_codec_type);
740     pos += 2;
741     little_endian_store_16(event, pos, media_codec.media_codec_information_len);
742     pos += 2;
743 
744     if (media_codec.media_codec_information_len < 100){
745         memcpy(event+pos, media_codec.media_codec_information, media_codec.media_codec_information_len);
746     } else {
747         memcpy(event+pos, media_codec.media_codec_information, 100);
748     }
749     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
750 }
751 
752 void avdtp_signaling_emit_media_codec_other_configuration(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
753     if (!callback) return;
754     avdtp_signaling_emit_media_codec_other(callback, con_handle, media_codec, 0);
755 }
756 
757 void avdtp_signaling_emit_media_codec_other_reconfiguration(btstack_packet_handler_t callback, uint16_t con_handle, adtvp_media_codec_capabilities_t media_codec){
758     if (!callback) return;
759     avdtp_signaling_emit_media_codec_other(callback, con_handle, media_codec, 1);
760 }
761 
762 
763 void avdtp_request_can_send_now_acceptor(avdtp_connection_t * connection, uint16_t l2cap_cid){
764     connection->wait_to_send_acceptor = 1;
765     l2cap_request_can_send_now_event(l2cap_cid);
766 }
767 void avdtp_request_can_send_now_initiator(avdtp_connection_t * connection, uint16_t l2cap_cid){
768     connection->wait_to_send_initiator = 1;
769     l2cap_request_can_send_now_event(l2cap_cid);
770 }
771 void avdtp_request_can_send_now_self(avdtp_connection_t * connection, uint16_t l2cap_cid){
772     connection->wait_to_send_self = 1;
773     l2cap_request_can_send_now_event(l2cap_cid);
774 }
775 
776 uint8_t avdtp_get_index_of_remote_stream_endpoint_with_seid(avdtp_stream_endpoint_t * stream_endpoint, uint16_t seid){
777     if (stream_endpoint->remote_seps[stream_endpoint->remote_sep_index].seid == seid){
778         return stream_endpoint->remote_sep_index;
779     }
780     int i;
781     for (i=0; i < stream_endpoint->remote_seps_num; i++){
782         if (stream_endpoint->remote_seps[i].seid == seid){
783             return i;
784         }
785     }
786     return 0xFF;
787 }
788