xref: /btstack/src/classic/avdtp_acceptor.c (revision 7cdc89a533ca236b2c2564b759993b788bae89d3)
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 #define BTSTACK_FILE__ "avdtp_acceptor.c"
38 
39 #include <stdint.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 
44 #include "btstack.h"
45 #include "classic/avdtp.h"
46 #include "classic/avdtp_util.h"
47 #include "classic/avdtp_acceptor.h"
48 
49 
50 static int avdtp_acceptor_send_accept_response(uint16_t cid,  uint8_t transaction_label, avdtp_signal_identifier_t identifier){
51     uint8_t command[2];
52     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_ACCEPT_MSG);
53     command[1] = (uint8_t)identifier;
54     return l2cap_send(cid, command, sizeof(command));
55 }
56 
57 static int avdtp_acceptor_process_chunk(avdtp_signaling_packet_t * signaling_packet, uint8_t * packet, uint16_t size){
58     (void)memcpy(signaling_packet->command + signaling_packet->size, packet,
59                  size);
60     signaling_packet->size += size;
61     return (signaling_packet->packet_type == AVDTP_SINGLE_PACKET) || (signaling_packet->packet_type == AVDTP_END_PACKET);
62 }
63 
64 static int avdtp_acceptor_validate_msg_length(avdtp_signal_identifier_t signal_identifier, uint16_t msg_size){
65     int minimal_msg_lenght = 2;
66     switch (signal_identifier){
67         case AVDTP_SI_GET_CAPABILITIES:
68         case AVDTP_SI_GET_ALL_CAPABILITIES:
69         case AVDTP_SI_SET_CONFIGURATION:
70         case AVDTP_SI_GET_CONFIGURATION:
71         case AVDTP_SI_START:
72         case AVDTP_SI_CLOSE:
73         case AVDTP_SI_ABORT:
74         case AVDTP_SI_RECONFIGURE:
75         case AVDTP_SI_OPEN:
76             minimal_msg_lenght = 3;
77             break;
78         default:
79             break;
80         }
81     return msg_size >= minimal_msg_lenght;
82 }
83 
84 static void avdtp_acceptor_handle_configuration_command(avdtp_connection_t *connection, avdtp_context_t *context, int offset, uint16_t packet_size, avdtp_stream_endpoint_t *stream_endpoint) {
85     log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_SET_CONFIGURATION connection %p", connection);
86     stream_endpoint->state = AVDTP_STREAM_ENDPOINT_CONFIGURATION_SUBSTATEMACHINE;
87     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_SET_CONFIGURATION;
88     connection->reject_service_category = 0;
89     stream_endpoint->connection = connection;
90     avdtp_sep_t sep;
91     sep.seid = connection->acceptor_signaling_packet.command[offset++] >> 2;
92     sep.configured_service_categories = avdtp_unpack_service_capabilities(connection, connection->acceptor_signaling_packet.signal_identifier, &sep.configuration, connection->acceptor_signaling_packet.command+offset, packet_size-offset);
93     sep.in_use = 1;
94 
95     if (connection->error_code){
96         log_info("fire configuration parsing errors ");
97         connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
98         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
99         return;
100     }
101     // find or add sep
102 
103     log_info("ACP .. seid %d, remote sep seid %d", sep.seid, stream_endpoint->remote_sep.seid);
104 
105     if (is_avdtp_remote_seid_registered(stream_endpoint)){
106         if (stream_endpoint->remote_sep.in_use){
107             log_info("reject as it is already in use");
108             connection->error_code = SEP_IN_USE;
109             // find first registered category and fire the error
110             connection->reject_service_category = 0;
111             int i;
112             for (i = 1; i < 9; i++){
113                 if (get_bit16(sep.configured_service_categories, i)){
114                     connection->reject_service_category = i;
115                     break;
116                 }
117             }
118             connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
119             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
120         } else {
121             stream_endpoint->remote_sep = sep;
122             log_info("ACP: update seid %d, to %p", stream_endpoint->remote_sep.seid, stream_endpoint);
123         }
124     } else {
125         // add new
126         log_info("ACP: seid %d not found in %p", sep.seid, stream_endpoint);
127         stream_endpoint->remote_sep = sep;
128         log_info("ACP: add seid %d, to %p", stream_endpoint->remote_sep.seid, stream_endpoint);
129     }
130 
131     avdtp_emit_configuration(context->avdtp_callback, connection->avdtp_cid, avdtp_local_seid(stream_endpoint), avdtp_remote_seid(stream_endpoint), &sep.configuration, sep.configured_service_categories);
132     avdtp_signaling_emit_accept(context->avdtp_callback, connection->avdtp_cid, avdtp_local_seid(stream_endpoint), connection->acceptor_signaling_packet.signal_identifier, false);
133 }
134 
135 void avdtp_acceptor_stream_config_subsm(avdtp_connection_t * connection, uint8_t * packet, uint16_t size, int offset, avdtp_context_t * context){
136     avdtp_stream_endpoint_t * stream_endpoint;
137     connection->acceptor_transaction_label = connection->acceptor_signaling_packet.transaction_label;
138     if (!avdtp_acceptor_validate_msg_length(connection->acceptor_signaling_packet.signal_identifier, size)) {
139         connection->error_code = BAD_LENGTH;
140         connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
141         connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
142         avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
143         return;
144     }
145 
146     // handle error cases
147     switch (connection->acceptor_signaling_packet.signal_identifier){
148         case AVDTP_SI_DISCOVER:
149             if (connection->state != AVDTP_SIGNALING_CONNECTION_OPENED) return;
150             log_info("ACP: AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_ANSWER_DISCOVER_SEPS");
151             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_ANSWER_DISCOVER_SEPS;
152             avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
153             return;
154         case AVDTP_SI_GET_CAPABILITIES:
155         case AVDTP_SI_GET_ALL_CAPABILITIES:
156         case AVDTP_SI_SET_CONFIGURATION:
157         case AVDTP_SI_GET_CONFIGURATION:
158         case AVDTP_SI_START:
159         case AVDTP_SI_CLOSE:
160         case AVDTP_SI_ABORT:
161         case AVDTP_SI_OPEN:
162         case AVDTP_SI_RECONFIGURE:
163         case AVDTP_SI_DELAYREPORT:
164             connection->acceptor_local_seid  = packet[offset++] >> 2;
165             stream_endpoint = avdtp_stream_endpoint_with_seid(connection->acceptor_local_seid, context);
166             if (!stream_endpoint){
167                 log_info("ACP: cmd %d - RESPONSE REJECT", connection->acceptor_signaling_packet.signal_identifier);
168                 connection->error_code = BAD_ACP_SEID;
169                 if (connection->acceptor_signaling_packet.signal_identifier == AVDTP_SI_OPEN){
170                     connection->error_code = BAD_STATE;
171                 }
172 
173                 connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
174                 if (connection->acceptor_signaling_packet.signal_identifier == AVDTP_SI_RECONFIGURE){
175                     connection->reject_service_category = connection->acceptor_local_seid;
176                     connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
177                 }
178                 connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
179                 avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
180                 return;
181             }
182             break;
183 
184         case AVDTP_SI_SUSPEND:{
185             int i;
186             log_info("ACP: AVDTP_SI_SUSPEND seids: ");
187             connection->num_suspended_seids = 0;
188 
189             for (i = offset; i < size; i++){
190                 connection->suspended_seids[connection->num_suspended_seids] = packet[i] >> 2;
191                 offset++;
192                 log_info("%d, ", connection->suspended_seids[connection->num_suspended_seids]);
193                 connection->num_suspended_seids++;
194             }
195 
196             if (connection->num_suspended_seids == 0) {
197                 log_info("ACP: CATEGORY RESPONSE REJECT BAD_ACP_SEID");
198                 connection->error_code = BAD_ACP_SEID;
199                 connection->reject_service_category = connection->acceptor_local_seid;
200                 connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
201                 connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
202                 avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
203                 return;
204             }
205             // deal with first susspended seid
206             connection->acceptor_local_seid = connection->suspended_seids[0];
207             stream_endpoint = avdtp_stream_endpoint_with_seid(connection->acceptor_local_seid, context);
208             if (!stream_endpoint){
209                 log_info("ACP: stream_endpoint not found, CATEGORY RESPONSE REJECT BAD_ACP_SEID");
210                 connection->error_code = BAD_ACP_SEID;
211                 connection->reject_service_category = connection->acceptor_local_seid;
212                 connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
213                 connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
214                 connection->num_suspended_seids = 0;
215                 avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
216                 return;
217             }
218             break;
219         }
220         default:
221             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_GENERAL_REJECT_WITH_ERROR_CODE;
222             connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
223             log_info("AVDTP_CMD_MSG signal %d not implemented, general reject", connection->acceptor_signaling_packet.signal_identifier);
224             avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
225             return;
226     }
227 
228     if (!stream_endpoint) {
229         return;
230     }
231 
232     if (!avdtp_acceptor_process_chunk(&connection->acceptor_signaling_packet, packet, size)) return;
233 
234     uint16_t packet_size = connection->acceptor_signaling_packet.size;
235     connection->acceptor_signaling_packet.size = 0;
236 
237     int request_to_send = 1;
238     switch (stream_endpoint->acceptor_config_state){
239         case AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE:
240             switch (connection->acceptor_signaling_packet.signal_identifier){
241                 case AVDTP_SI_DELAYREPORT:
242                     log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_DELAY_REPORT, local seid %d", connection->acceptor_local_seid);
243                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_DELAY_REPORT;
244                     avdtp_signaling_emit_delay(context->avdtp_callback, connection->avdtp_cid, connection->acceptor_local_seid, big_endian_read_16(packet, offset));
245                     break;
246 
247                 case AVDTP_SI_GET_ALL_CAPABILITIES:
248                     log_info("ACP: AVDTP_SI_GET_ALL_CAPABILITIES, local seid %d", connection->acceptor_local_seid);
249                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_GET_ALL_CAPABILITIES;
250                     break;
251                 case AVDTP_SI_GET_CAPABILITIES:
252                     log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_GET_CAPABILITIES, local seid %d", connection->acceptor_local_seid);
253                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_GET_CAPABILITIES;
254                     break;
255                 case AVDTP_SI_SET_CONFIGURATION:{
256                     // log_info("acceptor SM received SET_CONFIGURATION cmd: role is_initiator %d", connection->is_initiator);
257                     switch (connection->configuration_state){
258                         case AVDTP_CONFIGURATION_STATE_IDLE:
259                             avdtp_acceptor_handle_configuration_command(connection, context, offset, packet_size, stream_endpoint);
260                             connection->configuration_state = AVDTP_CONFIGURATION_STATE_REMOTE_INITIATED;
261                             break;
262                         case AVDTP_CONFIGURATION_STATE_LOCAL_INITIATED:
263                         case AVDTP_CONFIGURATION_STATE_LOCAL_CONFIGURED:
264                             log_info("ACP: Set configuration already initiated locally, reject cmd, local seid %d", connection->acceptor_local_seid);
265                             // send reject with category
266                             connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
267                             connection->reject_service_category = 0;
268                             connection->error_code = BAD_STATE;
269                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
270                             break;
271                         default:
272                             break;
273                     }
274                     break;
275                 }
276                 case AVDTP_SI_RECONFIGURE:{
277                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE;
278                     connection->reject_service_category = 0;
279 
280                     avdtp_sep_t sep;
281                     log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE, local seid %d, remote seid %d", connection->acceptor_local_seid, stream_endpoint->remote_sep.seid);
282                     sep.configured_service_categories = avdtp_unpack_service_capabilities(connection, connection->acceptor_signaling_packet.signal_identifier, &sep.configuration, connection->acceptor_signaling_packet.command+offset, packet_size-offset);
283                     if (connection->error_code){
284                         // fire configuration parsing errors
285                         connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
286                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
287                         break;
288                     }
289 
290                     // find sep or raise error
291                     if (!is_avdtp_remote_seid_registered(stream_endpoint)){
292                         log_info("ACP: REJECT AVDTP_SI_RECONFIGURE, BAD_ACP_SEID");
293                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
294                         connection->error_code = BAD_ACP_SEID;
295                         connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
296                         break;
297                     }
298                     stream_endpoint->remote_sep.configured_service_categories = sep.configured_service_categories;
299                     stream_endpoint->remote_sep.configuration = sep.configuration;
300 
301                     log_info("ACP: update active remote seid %d", stream_endpoint->remote_sep.seid);
302 
303                     avdtp_emit_configuration(context->avdtp_callback, connection->avdtp_cid, avdtp_local_seid(stream_endpoint), avdtp_remote_seid(stream_endpoint), &sep.configuration, sep.configured_service_categories);
304                     break;
305                 }
306 
307                 case AVDTP_SI_GET_CONFIGURATION:
308                     log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION");
309                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION;
310                     break;
311                 case AVDTP_SI_OPEN:
312                     if (stream_endpoint->state != AVDTP_STREAM_ENDPOINT_CONFIGURED){
313                         log_info("ACP: REJECT AVDTP_SI_OPEN, BAD_STATE");
314                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
315                         connection->error_code = BAD_STATE;
316                         connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
317                         break;
318                     }
319                     log_info("ACP: AVDTP_STREAM_ENDPOINT_W2_ANSWER_OPEN_STREAM");
320                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_OPEN_STREAM;
321                     stream_endpoint->state = AVDTP_STREAM_ENDPOINT_W4_L2CAP_FOR_MEDIA_CONNECTED;
322                     connection->acceptor_local_seid = stream_endpoint->sep.seid;
323                     break;
324                 case AVDTP_SI_START:
325                     if (stream_endpoint->state != AVDTP_STREAM_ENDPOINT_OPENED){
326                         log_info("ACP: REJECT AVDTP_SI_START, BAD_STATE, state %d", stream_endpoint->state);
327                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
328                         connection->error_code = BAD_STATE;
329                         connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
330                         break;
331                     }
332                     log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM");
333                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM;
334                     break;
335                 case AVDTP_SI_CLOSE:
336                     switch (stream_endpoint->state){
337                         case AVDTP_STREAM_ENDPOINT_OPENED:
338                         case AVDTP_STREAM_ENDPOINT_STREAMING:
339                             log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM");
340                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_CLOSING;
341                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM;
342                             break;
343                         default:
344                             log_info("ACP: AVDTP_SI_CLOSE, bad state %d ", stream_endpoint->state);
345                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
346                             connection->error_code = BAD_STATE;
347                             connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
348                             break;
349                     }
350                     break;
351                 case AVDTP_SI_ABORT:
352                      switch (stream_endpoint->state){
353                         case AVDTP_STREAM_ENDPOINT_CONFIGURED:
354                         case AVDTP_STREAM_ENDPOINT_CLOSING:
355                         case AVDTP_STREAM_ENDPOINT_OPENED:
356                         case AVDTP_STREAM_ENDPOINT_STREAMING:
357                             log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM");
358                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_ABORTING;
359                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM;
360                             break;
361                         default:
362                             log_info("ACP: AVDTP_SI_ABORT, bad state %d ", stream_endpoint->state);
363                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE;
364                             connection->error_code = BAD_STATE;
365                             connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
366                             break;
367                     }
368                     break;
369                 case AVDTP_SI_SUSPEND:
370                     log_info(" entering AVDTP_SI_SUSPEND");
371                     switch (stream_endpoint->state){
372                         case AVDTP_STREAM_ENDPOINT_OPENED:
373                         case AVDTP_STREAM_ENDPOINT_STREAMING:
374                             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_OPENED;
375                             connection->num_suspended_seids--;
376                             if (connection->num_suspended_seids <= 0){
377                                 log_info("ACP: AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM");
378                                 stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM;
379                             }
380                             break;
381                         default:
382                             log_info("ACP: AVDTP_SI_SUSPEND, bad state ");
383                             stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE;
384                             connection->error_code = BAD_STATE;
385                             connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
386                             break;
387                     }
388                     break;
389                 default:
390                     log_info("ACP: NOT IMPLEMENTED, Reject signal_identifier %02x", connection->acceptor_signaling_packet.signal_identifier);
391                     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_W2_REJECT_UNKNOWN_CMD;
392                     connection->reject_signal_identifier = connection->acceptor_signaling_packet.signal_identifier;
393                     break;
394             }
395             break;
396         default:
397             return;
398     }
399 
400     if (!request_to_send){
401         log_info("ACP: NOT IMPLEMENTED");
402     }
403     avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
404 }
405 
406 static int avdtp_acceptor_send_seps_response(uint16_t cid, uint8_t transaction_label, avdtp_stream_endpoint_t * endpoints){
407     uint8_t command[2+2*AVDTP_MAX_NUM_SEPS];
408     int pos = 0;
409     command[pos++] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_ACCEPT_MSG);
410     command[pos++] = (uint8_t)AVDTP_SI_DISCOVER;
411 
412     btstack_linked_list_iterator_t it;
413     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) endpoints);
414     while (btstack_linked_list_iterator_has_next(&it)){
415         avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
416         command[pos++] = (stream_endpoint->sep.seid << 2) | (stream_endpoint->sep.in_use<<1);
417         command[pos++] = (stream_endpoint->sep.media_type << 4) | (stream_endpoint->sep.type << 3);
418     }
419     return l2cap_send(cid, command, pos);
420 }
421 
422 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){
423     uint8_t command[4];
424     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
425     command[1] = (uint8_t)identifier;
426     command[2] = category;
427     command[3] = error_code;
428     return l2cap_send(cid, command, sizeof(command));
429 }
430 
431 static int avdtp_acceptor_send_response_general_reject(uint16_t cid, avdtp_signal_identifier_t identifier, uint8_t transaction_label){
432     uint8_t command[2];
433     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_GENERAL_REJECT_MSG);
434     command[1] = (uint8_t)identifier;
435     return l2cap_send(cid, command, sizeof(command));
436 }
437 
438 static int avdtp_acceptor_send_response_reject(uint16_t cid, avdtp_signal_identifier_t identifier, uint8_t transaction_label){
439     uint8_t command[2];
440     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
441     command[1] = (uint8_t)identifier;
442     return l2cap_send(cid, command, sizeof(command));
443 }
444 
445 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){
446     uint8_t command[3];
447     command[0] = avdtp_header(transaction_label, AVDTP_SINGLE_PACKET, AVDTP_RESPONSE_REJECT_MSG);
448     command[1] = (uint8_t)identifier;
449     command[2] = error_code;
450     return l2cap_send(cid, command, sizeof(command));
451 }
452 
453 void avdtp_acceptor_stream_config_subsm_run(avdtp_connection_t * connection, avdtp_context_t * context){
454     int sent = 1;
455     btstack_linked_list_t * stream_endpoints = &context->stream_endpoints;
456 
457     switch (connection->acceptor_connection_state){
458         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_ANSWER_DISCOVER_SEPS:
459             connection->state = AVDTP_SIGNALING_CONNECTION_OPENED;
460             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
461             avdtp_acceptor_send_seps_response(connection->l2cap_signaling_cid, connection->acceptor_transaction_label, (avdtp_stream_endpoint_t *) stream_endpoints);
462             break;
463         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE:
464             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
465             avdtp_acceptor_send_response_reject_with_error_code(connection->l2cap_signaling_cid, connection->reject_signal_identifier, connection->error_code, connection->acceptor_transaction_label);
466             break;
467         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE:
468             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
469             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);
470             break;
471         case AVDTP_SIGNALING_CONNECTION_ACCEPTOR_W2_GENERAL_REJECT_WITH_ERROR_CODE:
472             connection->acceptor_connection_state = AVDTP_SIGNALING_CONNECTION_ACCEPTOR_IDLE;
473             avdtp_acceptor_send_response_general_reject(connection->l2cap_signaling_cid, connection->reject_signal_identifier, connection->acceptor_transaction_label);
474             break;
475         default:
476             sent = 0;
477             break;
478     }
479     if (sent){
480         log_info("ACP: DONE");
481         return;
482     }
483 
484     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(connection->acceptor_local_seid, context);
485     if (!stream_endpoint) return;
486 
487     uint8_t reject_service_category = connection->reject_service_category;
488     avdtp_signal_identifier_t reject_signal_identifier = connection->reject_signal_identifier;
489     uint8_t error_code = connection->error_code;
490     uint16_t cid = stream_endpoint->connection ? stream_endpoint->connection->l2cap_signaling_cid : connection->l2cap_signaling_cid;
491     uint8_t trid = stream_endpoint->connection ? stream_endpoint->connection->acceptor_transaction_label : connection->acceptor_transaction_label;
492 
493     avdtp_acceptor_stream_endpoint_state_t acceptor_config_state = stream_endpoint->acceptor_config_state;
494     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE;
495     uint8_t * out_buffer;
496     uint16_t pos;
497 
498     bool emit_accept = false;
499     bool emit_reject = false;
500 
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->acceptor_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->acceptor_signaling_packet, out_buffer);
509             if ((connection->acceptor_signaling_packet.packet_type != AVDTP_SINGLE_PACKET) && (connection->acceptor_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                 emit_accept = true;
515             }
516             l2cap_send_prepared(cid, pos);
517             break;
518         case AVDTP_ACCEPTOR_W2_ANSWER_DELAY_REPORT:
519             log_info("ACP: DONE ");
520             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_DELAYREPORT);
521             emit_accept = true;
522             break;
523         case AVDTP_ACCEPTOR_W2_ANSWER_GET_ALL_CAPABILITIES:
524             avdtp_prepare_capabilities(&connection->acceptor_signaling_packet, trid, stream_endpoint->sep.registered_service_categories, stream_endpoint->sep.capabilities, AVDTP_SI_GET_ALL_CAPABILITIES);
525             l2cap_reserve_packet_buffer();
526             out_buffer = l2cap_get_outgoing_buffer();
527             pos = avdtp_signaling_create_fragment(cid, &connection->acceptor_signaling_packet, out_buffer);
528             if ((connection->acceptor_signaling_packet.packet_type != AVDTP_SINGLE_PACKET) && (connection->acceptor_signaling_packet.packet_type != AVDTP_END_PACKET)){
529                 stream_endpoint->acceptor_config_state = acceptor_config_state;
530                 log_info("ACP: fragmented");
531             } else {
532                 log_info("ACP:DONE");
533                 emit_accept = true;
534             }
535             l2cap_send_prepared(cid, pos);
536             break;
537         case AVDTP_ACCEPTOR_W2_ANSWER_SET_CONFIGURATION:
538             log_info("ACP: DONE");
539             log_info("    -> AVDTP_STREAM_ENDPOINT_CONFIGURED");
540             stream_endpoint->connection = connection;
541             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_CONFIGURED;
542             connection->configuration_state = AVDTP_CONFIGURATION_STATE_REMOTE_CONFIGURED;
543             // TODO: consider reconfiguration
544             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_SET_CONFIGURATION);
545             emit_accept = true;
546             break;
547         case AVDTP_ACCEPTOR_W2_ANSWER_RECONFIGURE:
548             log_info("ACP: DONE ");
549             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_RECONFIGURE);
550             emit_accept = true;
551             break;
552 
553         case AVDTP_ACCEPTOR_W2_ANSWER_GET_CONFIGURATION:{
554             avdtp_sep_t sep = stream_endpoint->remote_sep;
555             avdtp_prepare_capabilities(&connection->acceptor_signaling_packet, trid, sep.configured_service_categories, sep.configuration, AVDTP_SI_GET_CONFIGURATION);
556             l2cap_reserve_packet_buffer();
557             out_buffer = l2cap_get_outgoing_buffer();
558             pos = avdtp_signaling_create_fragment(cid, &connection->acceptor_signaling_packet, out_buffer);
559             if ((connection->acceptor_signaling_packet.packet_type != AVDTP_SINGLE_PACKET) && (connection->acceptor_signaling_packet.packet_type != AVDTP_END_PACKET)){
560                 stream_endpoint->acceptor_config_state = acceptor_config_state;
561                 log_info("ACP: fragmented");
562             } else {
563                 log_info("ACP:DONE");
564                 emit_accept = true;
565             }
566             l2cap_send_prepared(cid, pos);
567             break;
568         }
569         case AVDTP_ACCEPTOR_W2_ANSWER_OPEN_STREAM:
570             log_info("ACP: DONE");
571             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_OPEN);
572             emit_accept = true;
573             break;
574         case AVDTP_ACCEPTOR_W2_ANSWER_START_STREAM:
575             log_info("ACP: DONE ");
576             log_info("    -> AVDTP_STREAM_ENDPOINT_STREAMING ");
577             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_STREAMING;
578             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_START);
579             emit_accept = true;
580             break;
581         case AVDTP_ACCEPTOR_W2_ANSWER_CLOSE_STREAM:
582             log_info("ACP: DONE");
583             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_CLOSE);
584             emit_accept = true;
585             break;
586         case AVDTP_ACCEPTOR_W2_ANSWER_ABORT_STREAM:
587             log_info("ACP: DONE");
588             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_ABORT);
589             emit_accept = true;
590             break;
591         case AVDTP_ACCEPTOR_W2_ANSWER_SUSPEND_STREAM:
592             log_info("ACP: DONE");
593             stream_endpoint->state = AVDTP_STREAM_ENDPOINT_OPENED;
594             avdtp_acceptor_send_accept_response(cid, trid, AVDTP_SI_SUSPEND);
595             emit_accept = true;
596             break;
597         case AVDTP_ACCEPTOR_W2_REJECT_UNKNOWN_CMD:
598             log_info("ACP: DONE REJECT");
599             connection->reject_signal_identifier = AVDTP_SI_NONE;
600             avdtp_acceptor_send_response_reject(cid, reject_signal_identifier, trid);
601             emit_reject = true;
602             break;
603         case AVDTP_ACCEPTOR_W2_REJECT_CATEGORY_WITH_ERROR_CODE:
604             log_info("ACP: DONE REJECT CATEGORY");
605             connection->reject_service_category = 0;
606             avdtp_acceptor_send_response_reject_service_category(cid, reject_signal_identifier, reject_service_category, error_code, trid);
607             emit_reject = true;
608             break;
609         case AVDTP_ACCEPTOR_W2_REJECT_WITH_ERROR_CODE:
610             log_info("ACP: DONE REJECT");
611             connection->reject_signal_identifier = AVDTP_SI_NONE;
612             connection->error_code = 0;
613             avdtp_acceptor_send_response_reject_with_error_code(cid, reject_signal_identifier, error_code, trid);
614             emit_reject = true;
615             break;
616         default:
617             log_info("ACP: NOT IMPLEMENTED");
618             sent = 0;
619             break;
620     }
621     if (emit_accept == true){
622         avdtp_signaling_emit_accept(context->avdtp_callback, connection->avdtp_cid, avdtp_local_seid(stream_endpoint), connection->acceptor_signaling_packet.signal_identifier, false);
623     } else if (emit_reject == true){
624         avdtp_signaling_emit_reject(context->avdtp_callback, connection->avdtp_cid, avdtp_local_seid(stream_endpoint), connection->acceptor_signaling_packet.signal_identifier, false);
625     }
626     // check fragmentation
627     if ((connection->acceptor_signaling_packet.packet_type != AVDTP_SINGLE_PACKET) && (connection->acceptor_signaling_packet.packet_type != AVDTP_END_PACKET)){
628         avdtp_request_can_send_now_acceptor(connection, connection->l2cap_signaling_cid);
629     }
630 }
631