xref: /btstack/src/classic/avdtp_acceptor.c (revision b435e06234e531c17261f382423cd8c2f23dc22d)
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 #include <stdint.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 
43 #include "btstack.h"
44 #include "classic/avdtp.h"
45 #include "classic/avdtp_util.h"
46 #include "classic/avdtp_acceptor.h"
47 
48 
49 static int avdtp_acceptor_send_accept_response(uint16_t cid,  uint8_t transaction_label, avdtp_signal_identifier_t identifier){
50     uint8_t command[2];
51     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_ACCEPT_MSG);
52     command[1] = (uint8_t)identifier;
53     return l2cap_send(cid, command, sizeof(command));
54 }
55 
56 static int avdtp_acceptor_process_chunk(avdtp_signaling_packet_t * signaling_packet, uint8_t * packet, uint16_t size){
57     memcpy(signaling_packet->command + signaling_packet->size, packet, size);
58     signaling_packet->size += size;
59     return signaling_packet->packet_type == AVDTP_SINGLE_PACKET || signaling_packet->packet_type == AVDTP_END_PACKET;
60 }
61 
62 static int avdtp_acceptor_validate_msg_length(avdtp_signal_identifier_t signal_identifier, uint16_t msg_size){
63     int minimal_msg_lenght = 2;
64     switch (signal_identifier){
65         case AVDTP_SI_GET_CAPABILITIES:
66         case AVDTP_SI_GET_ALL_CAPABILITIES:
67         case AVDTP_SI_SET_CONFIGURATION:
68         case AVDTP_SI_GET_CONFIGURATION:
69         case AVDTP_SI_START:
70         case AVDTP_SI_CLOSE:
71         case AVDTP_SI_ABORT:
72         case AVDTP_SI_RECONFIGURE:
73         case AVDTP_SI_OPEN:
74             minimal_msg_lenght = 3;
75             break;
76         default:
77             break;
78         }
79     return msg_size >= minimal_msg_lenght;
80 }
81 
82 void avdtp_acceptor_stream_config_subsm(avdtp_connection_t * connection, uint8_t * packet, uint16_t size, int offset, avdtp_context_t * context){
83     avdtp_stream_endpoint_t * stream_endpoint;
84     connection->acceptor_transaction_label = connection->signaling_packet.transaction_label;
85 
86     if (!avdtp_acceptor_validate_msg_length(connection->signaling_packet.signal_identifier, size)) {
87         connection->error_code = BAD_LENGTH;
88         connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
89         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
90         avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
91         return;
92     }
93 
94     switch (connection->signaling_packet.signal_identifier){
95         case AVDTP_SI_DISCOVER:
96             if (connection->state != AVDTP_SIGNALING_CONNECTION_OPENED) return;
97             log_info("    ACP: AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_ANSWER_DISCOVER_SEPS");
98             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_ANSWER_DISCOVER_SEPS;
99             avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
100             return;
101         case AVDTP_SI_GET_CAPABILITIES:
102         case AVDTP_SI_GET_ALL_CAPABILITIES:
103         case AVDTP_SI_SET_CONFIGURATION:
104         case AVDTP_SI_GET_CONFIGURATION:
105         case AVDTP_SI_START:
106         case AVDTP_SI_CLOSE:
107         case AVDTP_SI_ABORT:
108         case AVDTP_SI_OPEN:
109         case AVDTP_SI_RECONFIGURE:
110             connection->query_seid  = packet[offset++] >> 2;
111             stream_endpoint = avdtp_stream_endpoint_with_seid(connection->query_seid, context);
112             if (!stream_endpoint){
113                 log_info("    ACP: cmd %d - RESPONSE REJECT", connection->signaling_packet.signal_identifier);
114                 connection->error_code = BAD_ACP_SEID;
115                 if (connection->signaling_packet.signal_identifier == AVDTP_SI_OPEN){
116                     connection->error_code = BAD_STATE;
117                 }
118 
119                 connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
120                 if (connection->signaling_packet.signal_identifier == AVDTP_SI_RECONFIGURE){
121                     connection->reject_service_category = connection->query_seid;
122                     connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
123                 }
124                 connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
125                 avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
126                 return;
127             }
128             break;
129 
130         case AVDTP_SI_SUSPEND:{
131             int i;
132             log_info("    ACP: AVDTP_SI_SUSPEND seids: ");
133             connection->num_suspended_seids = 0;
134 
135             for (i = offset; i < size; i++){
136                 connection->suspended_seids[connection->num_suspended_seids] = packet[i] >> 2;
137                 offset++;
138                 log_info("%d, ", connection->suspended_seids[connection->num_suspended_seids]);
139                 connection->num_suspended_seids++;
140             }
141 
142             if (connection->num_suspended_seids == 0) {
143                 log_info("    ACP: CATEGORY RESPONSE REJECT BAD_ACP_SEID");
144                 connection->error_code = BAD_ACP_SEID;
145                 connection->reject_service_category = connection->query_seid;
146                 connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
147                 connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
148                 avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
149                 return;
150             }
151             // deal with first susspended seid
152             connection->query_seid = connection->suspended_seids[0];
153             stream_endpoint = avdtp_stream_endpoint_with_seid(connection->query_seid, context);
154             if (!stream_endpoint){
155                 log_info("    ACP: stream_endpoint not found, CATEGORY RESPONSE REJECT BAD_ACP_SEID");
156                 connection->error_code = BAD_ACP_SEID;
157                 connection->reject_service_category = connection->query_seid;
158                 connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
159                 connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
160                 connection->num_suspended_seids = 0;
161                 avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
162                 return;
163             }
164             break;
165         }
166         default:
167             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_GENERAL_REJECT_WITH_ERROR_CODE;
168             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
169             log_info("AVDTP_CMD_MSG signal %d not implemented, general reject", connection->signaling_packet.signal_identifier);
170             avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
171             return;
172     }
173 
174     if (!stream_endpoint) {
175         return;
176     }
177 
178     if (!avdtp_acceptor_process_chunk(&connection->signaling_packet, packet, size)) return;
179 
180     uint16_t packet_size = connection->signaling_packet.size;
181     connection->signaling_packet.size = 0;
182 
183     int request_to_send = 1;
184     switch (stream_endpoint->acceptor_config_state){
185         case AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE:
186             switch (connection->signaling_packet.signal_identifier){
187                 case AVDTP_SI_GET_ALL_CAPABILITIES:
188                     log_info("    ACP: AVDTP_SI_GET_ALL_CAPABILITIES");
189                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_GET_ALL_CAPABILITIES;
190                     break;
191                 case AVDTP_SI_GET_CAPABILITIES:
192                     log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_GET_CAPABILITIES");
193                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_GET_CAPABILITIES;
194                     break;
195                 case AVDTP_SI_SET_CONFIGURATION:{
196                     log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_SET_CONFIGURATION ");
197                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_SET_CONFIGURATION;
198                     connection->reject_service_category = 0;
199                     stream_endpoint->connection = connection;
200                     avdtp_sep_t sep;
201                     sep.seid = connection->signaling_packet.command[offset++] >> 2;
202                     sep.configured_service_categories = avdtp_unpack_service_capabilities(connection, &sep.configuration, connection->signaling_packet.command+offset, packet_size-offset);
203                     sep.in_use = 1;
204 
205                     if (connection->error_code){
206                         log_info("fire configuration parsing errors ");
207                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
208                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
209                         break;
210                     }
211                     // find or add sep
212 
213                     stream_endpoint->remote_sep_index = avdtp_find_remote_sep(stream_endpoint->connection, sep.seid);
214                     log_info("    ACP .. seid %d, index %d", sep.seid, stream_endpoint->remote_sep_index);
215 
216                     if (stream_endpoint->remote_sep_index != AVDTP_INVALID_SEP_INDEX){
217                          if (stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].in_use){
218                             if (stream_endpoint->state < AVDTP_STREAM_ENDPOINT_OPENED){
219                                 stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index] = sep;
220                                 log_info("    ACP: update seid %d, to %p", stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].seid, stream_endpoint);
221                                 break;
222                             }
223                             // reject if already configured
224                             connection->error_code = SEP_IN_USE;
225                             // find first registered category and fire the error
226                             connection->reject_service_category = 0;
227                             int i;
228                             for (i = 1; i < 9; i++){
229                                 if (get_bit16(sep.configured_service_categories, i)){
230                                     connection->reject_service_category = i;
231                                     break;
232                                 }
233                             }
234                             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
235                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
236                         } else {
237                             stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index] = sep;
238                             log_info("    ACP: update seid %d, to %p", stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].seid, stream_endpoint);
239                         }
240                     } else {
241                         // add new
242                         log_info("    ACP: seid %d not found in %p", sep.seid, stream_endpoint);
243                         stream_endpoint->remote_sep_index = connection->remote_seps_num;
244                         connection->remote_seps_num++;
245                         connection->remote_seps[stream_endpoint->remote_sep_index] = sep;
246                         log_info("    ACP: add seid %d, to %p", connection->remote_seps[stream_endpoint->remote_sep_index].seid, stream_endpoint);
247                     }
248                     if (get_bit16(sep.configured_service_categories, AVDTP_MEDIA_CODEC)){
249                         switch (sep.configuration.media_codec.media_codec_type){
250                             case AVDTP_CODEC_SBC:
251                                 avdtp_signaling_emit_media_codec_sbc_configuration(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->acp_seid, sep.configuration.media_codec);
252                                 break;
253                             default:
254                                 avdtp_signaling_emit_media_codec_other_configuration(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->acp_seid, sep.configuration.media_codec);
255                                 break;
256                         }
257                     }
258                     avdtp_signaling_emit_accept(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->signaling_packet.signal_identifier, 0);
259                     break;
260                 }
261                 case AVDTP_SI_RECONFIGURE:{
262                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE;
263                     connection->reject_service_category = 0;
264 
265                     avdtp_sep_t sep;
266                     sep.seid = connection->query_seid;
267                     log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE seid %d", sep.seid);
268                     // log_info_hexdump(connection->signaling_packet.command, packet_size);
269 
270                     sep.configured_service_categories = avdtp_unpack_service_capabilities(connection, &sep.configuration, connection->signaling_packet.command+offset, packet_size-offset);
271 
272                     if (connection->error_code){
273                         // fire configuration parsing errors
274                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
275                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
276                         break;
277                     }
278 
279                     // find sep or raise error
280 
281                     stream_endpoint->remote_sep_index = avdtp_find_remote_sep(stream_endpoint->connection, sep.seid);
282                     if (stream_endpoint->remote_sep_index == AVDTP_INVALID_SEP_INDEX){
283                         log_info("    ACP: REJECT AVDTP_SI_RECONFIGURE, BAD_ACP_SEID");
284                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
285                         connection->error_code = BAD_ACP_SEID;
286                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
287                         break;
288                     }
289                     stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index] = sep;
290                     log_info("    ACP: update seid %d, to %p", stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].seid, stream_endpoint);
291 
292                     if (get_bit16(sep.configured_service_categories, AVDTP_MEDIA_CODEC)){
293                         switch (sep.capabilities.media_codec.media_codec_type){
294                             case AVDTP_CODEC_SBC:
295                                 avdtp_signaling_emit_media_codec_sbc_reconfiguration(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->acp_seid, sep.capabilities.media_codec);
296                                 break;
297                             default:
298                                 avdtp_signaling_emit_media_codec_other_reconfiguration(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->acp_seid, sep.capabilities.media_codec);
299                                 break;
300                         }
301                     }
302                     avdtp_signaling_emit_accept(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->signaling_packet.signal_identifier, 0);
303                     break;
304                 }
305 
306                 case AVDTP_SI_GET_CONFIGURATION:
307                     log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION");
308                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION;
309                     break;
310                 case AVDTP_SI_OPEN:
311                     if (stream_endpoint->state != AVDTP_STREAM_ENDPOINT_CONFIGURED){
312                         log_info("    ACP: REJECT AVDTP_SI_OPEN, BAD_STATE");
313                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
314                         connection->error_code = BAD_STATE;
315                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
316                         break;
317                     }
318                     log_info("    ACP: AVDTP_STREAM_ENDPOINT_W2_ANSWER_OPEN_STREAM");
319                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_OPEN_STREAM;
320                     stream_endpoint->state = AVDTP_STREAM_ENDPOINT_W4_L2CAP_FOR_MEDIA_CONNECTED;
321                     connection->query_seid = stream_endpoint->sep.seid;
322                     break;
323                 case AVDTP_SI_START:
324                     if (stream_endpoint->state != AVDTP_STREAM_ENDPOINT_OPENED){
325                         log_info("    ACP: REJECT AVDTP_SI_START, BAD_STATE");
326                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
327                         connection->error_code = BAD_STATE;
328                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
329                         break;
330                     }
331                     log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM");
332                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM;
333                     break;
334                 case AVDTP_SI_CLOSE:
335                     switch (stream_endpoint->state){
336                         case AVDTP_STREAM_ENDPOINT_OPENED:
337                         case AVDTP_STREAM_ENDPOINT_STREAMING:
338                             log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM");
339                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_CLOSING;
340                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM;
341                             break;
342                         default:
343                             log_info("    ACP: AVDTP_SI_CLOSE, bad state %d ", stream_endpoint->state);
344                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
345                             connection->error_code = BAD_STATE;
346                             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
347                             break;
348                     }
349                     break;
350                 case AVDTP_SI_ABORT:
351                      switch (stream_endpoint->state){
352                         case AVDTP_STREAM_ENDPOINT_CONFIGURED:
353                         case AVDTP_STREAM_ENDPOINT_CLOSING:
354                         case AVDTP_STREAM_ENDPOINT_OPENED:
355                         case AVDTP_STREAM_ENDPOINT_STREAMING:
356                             log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM");
357                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_ABORTING;
358                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM;
359                             break;
360                         default:
361                             log_info("    ACP: AVDTP_SI_ABORT, bad state %d ", stream_endpoint->state);
362                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
363                             connection->error_code = BAD_STATE;
364                             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
365                             break;
366                     }
367                     break;
368                 case AVDTP_SI_SUSPEND:
369                     log_info(" entering AVDTP_SI_SUSPEND");
370                     switch (stream_endpoint->state){
371                         case AVDTP_STREAM_ENDPOINT_OPENED:
372                         case AVDTP_STREAM_ENDPOINT_STREAMING:
373                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_OPENED;
374                             connection->num_suspended_seids--;
375                             if (connection->num_suspended_seids <= 0){
376                                 log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM");
377                                 stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM;
378                             }
379                             break;
380                         default:
381                             log_info("    ACP: AVDTP_SI_SUSPEND, bad state ");
382                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
383                             connection->error_code = BAD_STATE;
384                             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
385                             break;
386                     }
387 
388                     //stream_endpoint->state = AVDTP_STREAM_ENDPOINT_SUSPENDING;
389                     //stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_SUSPEND_STREAM;
390                     break;
391                 default:
392                     log_info("    ACP: NOT IMPLEMENTED, Reject signal_identifier %02x", connection->signaling_packet.signal_identifier);
393                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_UNKNOWN_CMD;
394                     connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
395                     break;
396             }
397             break;
398         default:
399             return;
400     }
401 
402     if (!request_to_send){
403         log_info("    ACP: NOT IMPLEMENTED");
404     }
405     avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
406 }
407 
408 static int avdtp_acceptor_send_seps_response(uint16_t cid, uint8_t transaction_label, avdtp_stream_endpoint_t * endpoints){
409     uint8_t command[2+2*MAX_NUM_SEPS];
410     int pos = 0;
411     command[pos++] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_ACCEPT_MSG);
412     command[pos++] = (uint8_t)AVDTP_SI_DISCOVER;
413 
414     btstack_linked_list_iterator_t it;
415     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) endpoints);
416     while (btstack_linked_list_iterator_has_next(&it)){
417         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
418         command[pos++] = (stream_endpoint->sep.seid << 2) | (stream_endpoint->sep.in_use<<1);
419         command[pos++] = (stream_endpoint->sep.media_type << 4) | (stream_endpoint->sep.type << 3);
420     }
421     return l2cap_send(cid, command, pos);
422 }
423 
424 static int avdtp_acceptor_send_response_reject_service_category(uint16_t cid,  avdtp_signal_identifier_t identifier, uint8_t category, uint8_t error_code, uint8_t transaction_label){
425     uint8_t command[4];
426     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
427     command[1] = (uint8_t)identifier;
428     command[2] = category;
429     command[3] = error_code;
430     return l2cap_send(cid, command, sizeof(command));
431 }
432 
433 static int avdtp_acceptor_send_response_general_reject(uint16_t cid, avdtp_signal_identifier_t identifier, uint8_t transaction_label){
434     uint8_t command[2];
435     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_GENERAL_REJECT_MSG);
436     command[1] = (uint8_t)identifier;
437     return l2cap_send(cid, command, sizeof(command));
438 }
439 
440 static int avdtp_acceptor_send_response_reject(uint16_t cid, avdtp_signal_identifier_t identifier, uint8_t transaction_label){
441     uint8_t command[2];
442     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
443     command[1] = (uint8_t)identifier;
444     return l2cap_send(cid, command, sizeof(command));
445 }
446 
447 static int avdtp_acceptor_send_response_reject_with_error_code(uint16_t cid, avdtp_signal_identifier_t identifier, uint8_t error_code, uint8_t transaction_label){
448     uint8_t command[3];
449     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
450     command[1] = (uint8_t)identifier;
451     command[2] = error_code;
452     return l2cap_send(cid, command, sizeof(command));
453 }
454 
455 void avdtp_acceptor_stream_config_subsm_run(avdtp_connection_t * connection, avdtp_context_t * context){
456     int sent = 1;
457     btstack_linked_list_t * stream_endpoints = &context->stream_endpoints;
458 
459     switch (connection->acceptor_connection_state){
460         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_ANSWER_DISCOVER_SEPS:
461             connection->state = AVDTP_SIGNALING_CONNECTION_OPENED;
462             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
463             avdtp_acceptor_send_seps_response(connection->l2cap_signaling_cid, connection->acceptor_transaction_label, (avdtp_stream_endpoint_t *) stream_endpoints);
464             break;
465         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE:
466             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
467             avdtp_acceptor_send_response_reject_with_error_code(connection->l2cap_signaling_cid, connection->reject_signal_identifier, connection->error_code, connection->acceptor_transaction_label);
468             break;
469         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE:
470             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
471             avdtp_acceptor_send_response_reject_service_category(connection->l2cap_signaling_cid, connection->reject_signal_identifier, connection->reject_service_category, connection->error_code, connection->acceptor_transaction_label);
472             break;
473         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_GENERAL_REJECT_WITH_ERROR_CODE:
474             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
475             avdtp_acceptor_send_response_general_reject(connection->l2cap_signaling_cid, connection->reject_signal_identifier, connection->acceptor_transaction_label);
476             break;
477         default:
478             sent = 0;
479             break;
480     }
481     if (sent){
482         log_info("    ACP: DONE");
483         return;
484     }
485 
486     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(connection->query_seid, context);
487     if (!stream_endpoint) return;
488 
489     uint8_t reject_service_category = connection->reject_service_category;
490     avdtp_signal_identifier_t reject_signal_identifier = connection->reject_signal_identifier;
491     uint8_t error_code = connection->error_code;
492     uint16_t cid = stream_endpoint->connection ? stream_endpoint->connection->l2cap_signaling_cid : connection->l2cap_signaling_cid;
493     uint8_t trid = stream_endpoint->connection ? stream_endpoint->connection->acceptor_transaction_label : connection->acceptor_transaction_label;
494 
495     avdtp_acceptor_stream_endpoint_state_t acceptor_config_state = stream_endpoint->acceptor_config_state;
496     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE;
497     uint8_t * out_buffer;
498     uint16_t pos;
499 
500     int status = 0;
501     switch (acceptor_config_state){
502         case AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE:
503             break;
504         case AVDTP_ACCEPTOR_W2_ANSWER_GET_CAPABILITIES:
505             avdtp_prepare_capabilities(&connection->signaling_packet, trid, stream_endpoint->sep.registered_service_categories, stream_endpoint->sep.capabilities, AVDTP_SI_GET_CAPABILITIES);
506             l2cap_reserve_packet_buffer();
507             out_buffer = l2cap_get_outgoing_buffer();
508             pos = avdtp_signaling_create_fragment(cid, &connection->signaling_packet, out_buffer);
509             if (connection->signaling_packet.packet_type != AVDTP_SINGLE_PACKET && connection->signaling_packet.packet_type != AVDTP_END_PACKET){
510                 stream_endpoint->acceptor_config_state = acceptor_config_state;
511                 log_info("    ACP: fragmented");
512             } else {
513                 log_info("    ACP:DONE");
514             }
515             l2cap_send_prepared(cid, pos);
516             break;
517         case AVDTP_ACCEPTOR_W2_ANSWER_GET_ALL_CAPABILITIES:
518             avdtp_prepare_capabilities(&connection->signaling_packet, trid, stream_endpoint->sep.registered_service_categories, stream_endpoint->sep.capabilities, AVDTP_SI_GET_ALL_CAPABILITIES);
519             l2cap_reserve_packet_buffer();
520             out_buffer = l2cap_get_outgoing_buffer();
521             pos = avdtp_signaling_create_fragment(cid, &connection->signaling_packet, out_buffer);
522             if (connection->signaling_packet.packet_type != AVDTP_SINGLE_PACKET && connection->signaling_packet.packet_type != AVDTP_END_PACKET){
523                 stream_endpoint->acceptor_config_state = acceptor_config_state;
524                 log_info("    ACP: fragmented");
525             } else {
526                 log_info("    ACP:DONE");
527             }
528             l2cap_send_prepared(cid, pos);
529             break;
530         case AVDTP_ACCEPTOR_W2_ANSWER_SET_CONFIGURATION:
531             log_info("    ACP: DONE");
532             log_info("    -> AVDTP_STREAM_ENDPOINT_CONFIGURED");
533             stream_endpoint->connection = connection;
534             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_CONFIGURED;
535             // TODO: consider reconfiguration
536             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_SET_CONFIGURATION);
537             break;
538         case AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE:
539             log_info("    ACP: DONE ");
540             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_RECONFIGURE);
541             break;
542 
543         case AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION:{
544             avdtp_sep_t sep = stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index];
545             avdtp_prepare_capabilities(&connection->signaling_packet, trid, sep.configured_service_categories, sep.configuration, AVDTP_SI_GET_CONFIGURATION);
546             l2cap_reserve_packet_buffer();
547             out_buffer = l2cap_get_outgoing_buffer();
548             pos = avdtp_signaling_create_fragment(cid, &connection->signaling_packet, out_buffer);
549             if (connection->signaling_packet.packet_type != AVDTP_SINGLE_PACKET && connection->signaling_packet.packet_type != AVDTP_END_PACKET){
550                 stream_endpoint->acceptor_config_state = acceptor_config_state;
551                 log_info("    ACP: fragmented");
552             } else {
553                 log_info("    ACP:DONE");
554             }
555             l2cap_send_prepared(cid, pos);
556             break;
557         }
558         case AVDTP_ACCEPTOR_W2_ANSWER_OPEN_STREAM:
559             log_info("    ACP: DONE");
560             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_OPEN);
561             break;
562         case AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM:
563             log_info("    ACP: DONE ");
564             log_info("    -> AVDTP_STREAM_ENDPOINT_STREAMING ");
565             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_STREAMING;
566             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_START);
567             break;
568         case AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM:
569             log_info("    ACP: DONE");
570             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_CLOSE);
571             break;
572         case AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM:
573             log_info("    ACP: DONE");
574             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_ABORT);
575             break;
576         case AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM:
577             log_info("    ACP: DONE");
578             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_OPENED;
579             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_SUSPEND);
580             break;
581         case AVDTP_ACCEPTOR_W2_REJECT_UNKNOWN_CMD:
582             status = 1;
583             log_info("    ACP: DONE REJECT");
584             connection->reject_signal_identifier = AVDTP_SI_NONE;
585             avdtp_acceptor_send_response_reject(cid, reject_signal_identifier, trid);
586             break;
587         case AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE:
588             status = 1;
589             log_info("    ACP: DONE REJECT CATEGORY");
590             connection->reject_service_category = 0;
591             avdtp_acceptor_send_response_reject_service_category(cid, reject_signal_identifier, reject_service_category, error_code, trid);
592             break;
593 
594         case AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE:
595             status = 1;
596             log_info("    ACP: DONE REJECT");
597             connection->reject_signal_identifier = AVDTP_SI_NONE;
598             connection->error_code = 0;
599             avdtp_acceptor_send_response_reject_with_error_code(cid, reject_signal_identifier, error_code, trid);
600             break;
601         default:
602             status = 0;
603             log_info("    ACP: NOT IMPLEMENTED");
604             sent = 0;
605     }
606     avdtp_signaling_emit_accept(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->signaling_packet.signal_identifier, status);
607 
608     // check fragmentation
609     if (connection->signaling_packet.packet_type != AVDTP_SINGLE_PACKET && connection->signaling_packet.packet_type != AVDTP_END_PACKET){
610         avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
611     }
612 }
613