xref: /btstack/src/classic/avdtp_acceptor.c (revision 58c560219426df86e08670b9ca7d3d1f9979a6c1)
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                             // reject if already configured
219                             connection->error_code = SEP_IN_USE;
220                             // find first registered category and fire the error
221                             connection->reject_service_category = 0;
222                             int i;
223                             for (i = 1; i < 9; i++){
224                                 if (get_bit16(sep.configured_service_categories, i)){
225                                     connection->reject_service_category = i;
226                                     break;
227                                 }
228                             }
229                             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
230                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
231                         } else {
232                             stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index] = sep;
233                             log_info("    ACP: update seid %d, to %p", stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].seid, stream_endpoint);
234                         }
235                     } else {
236                         // add new
237                         log_info("    ACP: seid %d not found in %p", sep.seid, stream_endpoint);
238                         stream_endpoint->remote_sep_index = connection->remote_seps_num;
239                         connection->remote_seps_num++;
240                         connection->remote_seps[stream_endpoint->remote_sep_index] = sep;
241                         log_info("    ACP: add seid %d, to %p", connection->remote_seps[stream_endpoint->remote_sep_index].seid, stream_endpoint);
242                     }
243                     if (get_bit16(sep.configured_service_categories, AVDTP_MEDIA_CODEC)){
244                         switch (sep.configuration.media_codec.media_codec_type){
245                             case AVDTP_CODEC_SBC:
246                                 avdtp_signaling_emit_media_codec_sbc_configuration(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->acp_seid, sep.configuration.media_codec);
247                                 break;
248                             default:
249                                 avdtp_signaling_emit_media_codec_other_configuration(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->acp_seid, sep.configuration.media_codec);
250                                 break;
251                         }
252                     }
253                     avdtp_signaling_emit_accept(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->signaling_packet.signal_identifier, 0);
254                     break;
255                 }
256                 case AVDTP_SI_RECONFIGURE:{
257                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE;
258                     connection->reject_service_category = 0;
259 
260                     avdtp_sep_t sep;
261                     sep.seid = connection->query_seid;
262                     log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE seid %d", sep.seid);
263                     // log_info_hexdump(connection->signaling_packet.command, packet_size);
264 
265                     sep.configured_service_categories = avdtp_unpack_service_capabilities(connection, &sep.configuration, connection->signaling_packet.command+offset, packet_size-offset);
266 
267                     if (connection->error_code){
268                         // fire configuration parsing errors
269                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
270                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
271                         break;
272                     }
273 
274                     // find sep or raise error
275 
276                     stream_endpoint->remote_sep_index = avdtp_find_remote_sep(stream_endpoint->connection, sep.seid);
277                     if (stream_endpoint->remote_sep_index == AVDTP_INVALID_SEP_INDEX){
278                         log_info("    ACP: REJECT AVDTP_SI_RECONFIGURE, BAD_ACP_SEID");
279                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
280                         connection->error_code = BAD_ACP_SEID;
281                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
282                         break;
283                     }
284                     stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index] = sep;
285                     log_info("    ACP: update seid %d, to %p", stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index].seid, stream_endpoint);
286 
287                     if (get_bit16(sep.configured_service_categories, AVDTP_MEDIA_CODEC)){
288                         switch (sep.capabilities.media_codec.media_codec_type){
289                             case AVDTP_CODEC_SBC:
290                                 avdtp_signaling_emit_media_codec_sbc_reconfiguration(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->acp_seid, sep.capabilities.media_codec);
291                                 break;
292                             default:
293                                 avdtp_signaling_emit_media_codec_other_reconfiguration(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->acp_seid, sep.capabilities.media_codec);
294                                 break;
295                         }
296                     }
297                     avdtp_signaling_emit_accept(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->signaling_packet.signal_identifier, 0);
298                     break;
299                 }
300 
301                 case AVDTP_SI_GET_CONFIGURATION:
302                     log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION");
303                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION;
304                     break;
305                 case AVDTP_SI_OPEN:
306                     if (stream_endpoint->state != AVDTP_STREAM_ENDPOINT_CONFIGURED){
307                         log_info("    ACP: REJECT AVDTP_SI_OPEN, BAD_STATE");
308                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
309                         connection->error_code = BAD_STATE;
310                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
311                         break;
312                     }
313                     log_info("    ACP: AVDTP_STREAM_ENDPOINT_W2_ANSWER_OPEN_STREAM");
314                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_OPEN_STREAM;
315                     stream_endpoint->state = AVDTP_STREAM_ENDPOINT_W4_L2CAP_FOR_MEDIA_CONNECTED;
316                     connection->query_seid = stream_endpoint->sep.seid;
317                     break;
318                 case AVDTP_SI_START:
319                     if (stream_endpoint->state != AVDTP_STREAM_ENDPOINT_OPENED){
320                         log_info("    ACP: REJECT AVDTP_SI_START, BAD_STATE");
321                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
322                         connection->error_code = BAD_STATE;
323                         connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
324                         break;
325                     }
326                     log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM");
327                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM;
328                     break;
329                 case AVDTP_SI_CLOSE:
330                     switch (stream_endpoint->state){
331                         case AVDTP_STREAM_ENDPOINT_OPENED:
332                         case AVDTP_STREAM_ENDPOINT_STREAMING:
333                             log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM");
334                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_CLOSING;
335                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM;
336                             break;
337                         default:
338                             log_info("    ACP: AVDTP_SI_CLOSE, bad state %d ", stream_endpoint->state);
339                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
340                             connection->error_code = BAD_STATE;
341                             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
342                             break;
343                     }
344                     break;
345                 case AVDTP_SI_ABORT:
346                      switch (stream_endpoint->state){
347                         case AVDTP_STREAM_ENDPOINT_CONFIGURED:
348                         case AVDTP_STREAM_ENDPOINT_CLOSING:
349                         case AVDTP_STREAM_ENDPOINT_OPENED:
350                         case AVDTP_STREAM_ENDPOINT_STREAMING:
351                             log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM");
352                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_ABORTING;
353                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM;
354                             break;
355                         default:
356                             log_info("    ACP: AVDTP_SI_ABORT, bad state %d ", stream_endpoint->state);
357                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
358                             connection->error_code = BAD_STATE;
359                             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
360                             break;
361                     }
362                     break;
363                 case AVDTP_SI_SUSPEND:
364                     log_info(" entering AVDTP_SI_SUSPEND");
365                     switch (stream_endpoint->state){
366                         case AVDTP_STREAM_ENDPOINT_OPENED:
367                         case AVDTP_STREAM_ENDPOINT_STREAMING:
368                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_OPENED;
369                             connection->num_suspended_seids--;
370                             if (connection->num_suspended_seids <= 0){
371                                 log_info("    ACP: AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM");
372                                 stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM;
373                             }
374                             break;
375                         default:
376                             log_info("    ACP: AVDTP_SI_SUSPEND, bad state ");
377                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
378                             connection->error_code = BAD_STATE;
379                             connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
380                             break;
381                     }
382 
383                     //stream_endpoint->state = AVDTP_STREAM_ENDPOINT_SUSPENDING;
384                     //stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_SUSPEND_STREAM;
385                     break;
386                 default:
387                     log_info("    ACP: NOT IMPLEMENTED, Reject signal_identifier %02x", connection->signaling_packet.signal_identifier);
388                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_UNKNOWN_CMD;
389                     connection->reject_signal_identifier = connection->signaling_packet.signal_identifier;
390                     break;
391             }
392             break;
393         default:
394             return;
395     }
396 
397     if (!request_to_send){
398         log_info("    ACP: NOT IMPLEMENTED");
399     }
400     avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
401 }
402 
403 static int avdtp_acceptor_send_seps_response(uint16_t cid, uint8_t transaction_label, avdtp_stream_endpoint_t * endpoints){
404     uint8_t command[2+2*MAX_NUM_SEPS];
405     int pos = 0;
406     command[pos++] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_ACCEPT_MSG);
407     command[pos++] = (uint8_t)AVDTP_SI_DISCOVER;
408 
409     btstack_linked_list_iterator_t it;
410     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) endpoints);
411     while (btstack_linked_list_iterator_has_next(&it)){
412         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
413         command[pos++] = (stream_endpoint->sep.seid << 2) | (stream_endpoint->sep.in_use<<1);
414         command[pos++] = (stream_endpoint->sep.media_type << 4) | (stream_endpoint->sep.type << 3);
415     }
416     return l2cap_send(cid, command, pos);
417 }
418 
419 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){
420     uint8_t command[4];
421     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
422     command[1] = (uint8_t)identifier;
423     command[2] = category;
424     command[3] = error_code;
425     return l2cap_send(cid, command, sizeof(command));
426 }
427 
428 static int avdtp_acceptor_send_response_general_reject(uint16_t cid, avdtp_signal_identifier_t identifier, uint8_t transaction_label){
429     uint8_t command[2];
430     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_GENERAL_REJECT_MSG);
431     command[1] = (uint8_t)identifier;
432     return l2cap_send(cid, command, sizeof(command));
433 }
434 
435 static int avdtp_acceptor_send_response_reject(uint16_t cid, avdtp_signal_identifier_t identifier, uint8_t transaction_label){
436     uint8_t command[2];
437     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
438     command[1] = (uint8_t)identifier;
439     return l2cap_send(cid, command, sizeof(command));
440 }
441 
442 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){
443     uint8_t command[3];
444     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
445     command[1] = (uint8_t)identifier;
446     command[2] = error_code;
447     return l2cap_send(cid, command, sizeof(command));
448 }
449 
450 void avdtp_acceptor_stream_config_subsm_run(avdtp_connection_t * connection, avdtp_context_t * context){
451     int sent = 1;
452     btstack_linked_list_t * stream_endpoints = &context->stream_endpoints;
453 
454     switch (connection->acceptor_connection_state){
455         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_ANSWER_DISCOVER_SEPS:
456             connection->state = AVDTP_SIGNALING_CONNECTION_OPENED;
457             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
458             avdtp_acceptor_send_seps_response(connection->l2cap_signaling_cid, connection->acceptor_transaction_label, (avdtp_stream_endpoint_t *) stream_endpoints);
459             break;
460         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE:
461             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
462             avdtp_acceptor_send_response_reject_with_error_code(connection->l2cap_signaling_cid, connection->reject_signal_identifier, connection->error_code, connection->acceptor_transaction_label);
463             break;
464         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE:
465             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
466             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);
467             break;
468         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_GENERAL_REJECT_WITH_ERROR_CODE:
469             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
470             avdtp_acceptor_send_response_general_reject(connection->l2cap_signaling_cid, connection->reject_signal_identifier, connection->acceptor_transaction_label);
471             break;
472         default:
473             sent = 0;
474             break;
475     }
476     if (sent){
477         log_info("    ACP: DONE");
478         return;
479     }
480 
481     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(connection->query_seid, context);
482     if (!stream_endpoint) return;
483 
484     uint8_t reject_service_category = connection->reject_service_category;
485     avdtp_signal_identifier_t reject_signal_identifier = connection->reject_signal_identifier;
486     uint8_t error_code = connection->error_code;
487     uint16_t cid = stream_endpoint->connection ? stream_endpoint->connection->l2cap_signaling_cid : connection->l2cap_signaling_cid;
488     uint8_t trid = stream_endpoint->connection ? stream_endpoint->connection->acceptor_transaction_label : connection->acceptor_transaction_label;
489 
490     avdtp_acceptor_stream_endpoint_state_t acceptor_config_state = stream_endpoint->acceptor_config_state;
491     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE;
492     uint8_t * out_buffer;
493     uint16_t pos;
494 
495     int status = 0;
496     switch (acceptor_config_state){
497         case AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE:
498             break;
499         case AVDTP_ACCEPTOR_W2_ANSWER_GET_CAPABILITIES:
500             avdtp_prepare_capabilities(&connection->signaling_packet, trid, stream_endpoint->sep.registered_service_categories, stream_endpoint->sep.capabilities, AVDTP_SI_GET_CAPABILITIES);
501             l2cap_reserve_packet_buffer();
502             out_buffer = l2cap_get_outgoing_buffer();
503             pos = avdtp_signaling_create_fragment(cid, &connection->signaling_packet, out_buffer);
504             if (connection->signaling_packet.packet_type != AVDTP_SINGLE_PACKET && connection->signaling_packet.packet_type != AVDTP_END_PACKET){
505                 stream_endpoint->acceptor_config_state = acceptor_config_state;
506                 log_info("    ACP: fragmented");
507             } else {
508                 log_info("    ACP:DONE");
509             }
510             l2cap_send_prepared(cid, pos);
511             break;
512         case AVDTP_ACCEPTOR_W2_ANSWER_GET_ALL_CAPABILITIES:
513             avdtp_prepare_capabilities(&connection->signaling_packet, trid, stream_endpoint->sep.registered_service_categories, stream_endpoint->sep.capabilities, AVDTP_SI_GET_ALL_CAPABILITIES);
514             l2cap_reserve_packet_buffer();
515             out_buffer = l2cap_get_outgoing_buffer();
516             pos = avdtp_signaling_create_fragment(cid, &connection->signaling_packet, out_buffer);
517             if (connection->signaling_packet.packet_type != AVDTP_SINGLE_PACKET && connection->signaling_packet.packet_type != AVDTP_END_PACKET){
518                 stream_endpoint->acceptor_config_state = acceptor_config_state;
519                 log_info("    ACP: fragmented");
520             } else {
521                 log_info("    ACP:DONE");
522             }
523             l2cap_send_prepared(cid, pos);
524             break;
525         case AVDTP_ACCEPTOR_W2_ANSWER_SET_CONFIGURATION:
526             log_info("    ACP: DONE");
527             log_info("    -> AVDTP_STREAM_ENDPOINT_CONFIGURED");
528             stream_endpoint->connection = connection;
529             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_CONFIGURED;
530             // TODO: consider reconfiguration
531             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_SET_CONFIGURATION);
532             break;
533         case AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE:
534             log_info("    ACP: DONE ");
535             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_RECONFIGURE);
536             break;
537 
538         case AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION:{
539             avdtp_sep_t sep = stream_endpoint->connection->remote_seps[stream_endpoint->remote_sep_index];
540             avdtp_prepare_capabilities(&connection->signaling_packet, trid, sep.configured_service_categories, sep.configuration, AVDTP_SI_GET_CONFIGURATION);
541             l2cap_reserve_packet_buffer();
542             out_buffer = l2cap_get_outgoing_buffer();
543             pos = avdtp_signaling_create_fragment(cid, &connection->signaling_packet, out_buffer);
544             if (connection->signaling_packet.packet_type != AVDTP_SINGLE_PACKET && connection->signaling_packet.packet_type != AVDTP_END_PACKET){
545                 stream_endpoint->acceptor_config_state = acceptor_config_state;
546                 log_info("    ACP: fragmented");
547             } else {
548                 log_info("    ACP:DONE");
549             }
550             l2cap_send_prepared(cid, pos);
551             break;
552         }
553         case AVDTP_ACCEPTOR_W2_ANSWER_OPEN_STREAM:
554             log_info("    ACP: DONE");
555             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_OPEN);
556             break;
557         case AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM:
558             log_info("    ACP: DONE ");
559             log_info("    -> AVDTP_STREAM_ENDPOINT_STREAMING ");
560             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_STREAMING;
561             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_START);
562             break;
563         case AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM:
564             log_info("    ACP: DONE");
565             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_CLOSE);
566             break;
567         case AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM:
568             log_info("    ACP: DONE");
569             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_ABORT);
570             break;
571         case AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM:
572             log_info("    ACP: DONE");
573             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_OPENED;
574             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_SUSPEND);
575             break;
576         case AVDTP_ACCEPTOR_W2_REJECT_UNKNOWN_CMD:
577             status = 1;
578             log_info("    ACP: DONE REJECT");
579             connection->reject_signal_identifier = AVDTP_SI_NONE;
580             avdtp_acceptor_send_response_reject(cid, reject_signal_identifier, trid);
581             break;
582         case AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE:
583             status = 1;
584             log_info("    ACP: DONE REJECT CATEGORY");
585             connection->reject_service_category = 0;
586             avdtp_acceptor_send_response_reject_service_category(cid, reject_signal_identifier, reject_service_category, error_code, trid);
587             break;
588 
589         case AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE:
590             status = 1;
591             log_info("    ACP: DONE REJECT");
592             connection->reject_signal_identifier = AVDTP_SI_NONE;
593             connection->error_code = 0;
594             avdtp_acceptor_send_response_reject_with_error_code(cid, reject_signal_identifier, error_code, trid);
595             break;
596         default:
597             status = 0;
598             log_info("    ACP: NOT IMPLEMENTED");
599             sent = 0;
600     }
601     avdtp_signaling_emit_accept(context->avdtp_callback, connection->con_handle, connection->int_seid, connection->signaling_packet.signal_identifier, status);
602 
603     // check fragmentation
604     if (connection->signaling_packet.packet_type != AVDTP_SINGLE_PACKET && connection->signaling_packet.packet_type != AVDTP_END_PACKET){
605         avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
606     }
607 }
608