xref: /btstack/src/classic/goep_client.c (revision d0f26bf0c78bf52a56173adb9e57b021e5ec80cc)
1 /*
2  * Copyright (C) 2014 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 BLUEKITCHEN
24  * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "goep_client.c"
39 
40 #include "btstack_config.h"
41 
42 #include <stdint.h>
43 #include <string.h>
44 
45 #include "btstack_debug.h"
46 #include "hci_dump.h"
47 #include "bluetooth_sdp.h"
48 #include "btstack_event.h"
49 #include "classic/goep_client.h"
50 #include "classic/obex_message_builder.h"
51 #include "classic/obex.h"
52 #include "classic/obex_iterator.h"
53 #include "classic/rfcomm.h"
54 #include "classic/sdp_client.h"
55 #include "classic/sdp_util.h"
56 #include "l2cap.h"
57 
58 //------------------------------------------------------------------------------------------------------------
59 // goep_client.c
60 //
61 
62 #ifdef ENABLE_GOEP_L2CAP
63 #ifndef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE
64 #error "ENABLE_GOEP_L2CAP requires ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE. Please enable ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE or disable ENABLE_GOEP_L2CAP"
65 #endif
66 #endif
67 
68 static uint16_t goep_client_cid;
69 static btstack_linked_list_t goep_clients;
70 
71 static goep_client_t *    goep_client_sdp_active;
72 static uint8_t            goep_client_sdp_query_attribute_value[30];
73 static const unsigned int goep_client_sdp_query_attribute_value_buffer_size = sizeof(goep_client_sdp_query_attribute_value);
74 static uint8_t goep_packet_buffer[150];
75 
76 // singleton instance
77 static goep_client_t   goep_client_singleton;
78 
79 #ifdef ENABLE_GOEP_L2CAP
80 // singleton instance
81 static uint8_t goep_client_singleton_ertm_buffer[1000];
82 static l2cap_ertm_config_t goep_client_singleton_ertm_config = {
83     1,  // ertm mandatory
84     2,  // max transmit, some tests require > 1
85     2000,
86     12000,
87     512,    // l2cap ertm mtu
88     2,
89     2,
90     1,      // 16-bit FCS
91 };
92 #endif
93 
94 static inline void goep_client_emit_connected_event(goep_client_t * goep_client, uint8_t status){
95     uint8_t event[15];
96     int pos = 0;
97     event[pos++] = HCI_EVENT_GOEP_META;
98     pos++;  // skip len
99     event[pos++] = GOEP_SUBEVENT_CONNECTION_OPENED;
100     little_endian_store_16(event, pos, goep_client->cid);
101     pos+=2;
102     event[pos++] = status;
103     (void)memcpy(&event[pos], goep_client->bd_addr, 6);
104     pos += 6;
105     little_endian_store_16(event, pos, goep_client->con_handle);
106     pos += 2;
107     event[pos++] = goep_client->incoming;
108     event[1] = pos - 2;
109     if (pos != sizeof(event)) log_error("goep_client_emit_connected_event size %u", pos);
110     goep_client->client_handler(HCI_EVENT_PACKET, goep_client->cid, &event[0], pos);
111 }
112 
113 static inline void goep_client_emit_connection_closed_event(goep_client_t * goep_client){
114     uint8_t event[5];
115     int pos = 0;
116     event[pos++] = HCI_EVENT_GOEP_META;
117     pos++;  // skip len
118     event[pos++] = GOEP_SUBEVENT_CONNECTION_CLOSED;
119     little_endian_store_16(event, pos, goep_client->cid);
120     pos+=2;
121     event[1] = pos - 2;
122     if (pos != sizeof(event)) log_error("goep_client_emit_connection_closed_event size %u", pos);
123     goep_client->client_handler(HCI_EVENT_PACKET, goep_client->cid, &event[0], pos);
124 }
125 
126 static inline void goep_client_emit_can_send_now_event(goep_client_t * goep_client){
127     uint8_t event[5];
128     int pos = 0;
129     event[pos++] = HCI_EVENT_GOEP_META;
130     pos++;  // skip len
131     event[pos++] = GOEP_SUBEVENT_CAN_SEND_NOW;
132     little_endian_store_16(event, pos, goep_client->cid);
133     pos+=2;
134     event[1] = pos - 2;
135     if (pos != sizeof(event)) log_error("goep_client_emit_can_send_now_event size %u", pos);
136     goep_client->client_handler(HCI_EVENT_PACKET, goep_client->cid, &event[0], pos);
137 }
138 
139 static void goep_client_handle_connection_opened(goep_client_t * goep_client, uint8_t status, uint16_t mtu){
140     if (status) {
141         goep_client->state = GOEP_CLIENT_INIT;
142         log_info("goep_client: open failed, status %u", status);
143     } else {
144         goep_client->bearer_mtu = mtu;
145         goep_client->state = GOEP_CLIENT_CONNECTED;
146         log_info("goep_client: connection opened. cid %u, max frame size %u", goep_client->bearer_cid, goep_client->bearer_mtu);
147     }
148     goep_client_emit_connected_event(goep_client, status);
149 }
150 
151 static void goep_client_handle_connection_close(goep_client_t * goep_client){
152     goep_client->state = GOEP_CLIENT_INIT;
153     btstack_linked_list_remove(&goep_clients, (btstack_linked_item_t *) goep_client);
154     goep_client_emit_connection_closed_event(goep_client);
155 }
156 
157 static goep_client_t * goep_client_for_cid(uint16_t cid){
158     btstack_linked_list_iterator_t it;
159     btstack_linked_list_iterator_init(&it, &goep_clients);
160     while (btstack_linked_list_iterator_has_next(&it)){
161         goep_client_t * goep_client = (goep_client_t *) btstack_linked_list_iterator_next(&it);
162         if (goep_client->cid == cid){
163             return goep_client;
164         }
165     }
166     return NULL;
167 }
168 
169 static goep_client_t * goep_client_for_bearer_cid(uint16_t bearer_cid){
170     if (bearer_cid == goep_client_singleton.bearer_cid){
171         return &goep_client_singleton;
172     } else {
173         btstack_linked_list_iterator_t it;
174         btstack_linked_list_iterator_init(&it, &goep_clients);
175         while (btstack_linked_list_iterator_has_next(&it)){
176             goep_client_t * goep_client = (goep_client_t *) btstack_linked_list_iterator_next(&it);
177             if (goep_client->bearer_cid == bearer_cid){
178                 return goep_client;
179             }
180         }
181         return NULL;
182     }
183 }
184 
185 static void goep_client_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
186     UNUSED(channel);
187     UNUSED(size);
188     goep_client_t * goep_client;
189     switch (packet_type){
190         case HCI_EVENT_PACKET:
191             switch (hci_event_packet_get_type(packet)) {
192 #ifdef ENABLE_GOEP_L2CAP
193                 case L2CAP_EVENT_CHANNEL_OPENED:
194                     goep_client = goep_client_for_bearer_cid(l2cap_event_channel_opened_get_local_cid(packet));
195                     btstack_assert(goep_client != NULL);
196                     goep_client_handle_connection_opened(goep_client, l2cap_event_channel_opened_get_status(packet),
197                                                          btstack_min(l2cap_event_channel_opened_get_remote_mtu(packet), l2cap_event_channel_opened_get_local_mtu(packet)));
198                     break;
199                 case L2CAP_EVENT_CAN_SEND_NOW:
200                     goep_client = goep_client_for_bearer_cid(l2cap_event_can_send_now_get_local_cid(packet));
201                     btstack_assert(goep_client != NULL);
202                     goep_client_emit_can_send_now_event(goep_client);
203                     break;
204                 case L2CAP_EVENT_CHANNEL_CLOSED:
205                     goep_client = goep_client_for_bearer_cid(l2cap_event_channel_closed_get_local_cid(packet));
206                     btstack_assert(goep_client != NULL);
207                     goep_client_handle_connection_close(goep_client);
208                     break;
209 #endif
210                 case RFCOMM_EVENT_CHANNEL_OPENED:
211                     goep_client = goep_client_for_bearer_cid(rfcomm_event_channel_opened_get_rfcomm_cid(packet));
212                     btstack_assert(goep_client != NULL);
213                     goep_client_handle_connection_opened(goep_client, rfcomm_event_channel_opened_get_status(packet), rfcomm_event_channel_opened_get_max_frame_size(packet));
214                     return;
215                 case RFCOMM_EVENT_CAN_SEND_NOW:
216                     goep_client = goep_client_for_bearer_cid(rfcomm_event_can_send_now_get_rfcomm_cid(packet));
217                     btstack_assert(goep_client != NULL);
218                     goep_client_emit_can_send_now_event(goep_client);
219                     break;
220                 case RFCOMM_EVENT_CHANNEL_CLOSED:
221                     goep_client = goep_client_for_bearer_cid(rfcomm_event_channel_closed_get_rfcomm_cid(packet));
222                     btstack_assert(goep_client != NULL);
223                     goep_client_handle_connection_close(goep_client);
224                     break;
225                 default:
226                     break;
227             }
228             break;
229         case L2CAP_DATA_PACKET:
230         case RFCOMM_DATA_PACKET:
231             goep_client = goep_client_for_bearer_cid(channel);
232             btstack_assert(goep_client != NULL);
233             goep_client->client_handler(GOEP_DATA_PACKET, goep_client->cid, packet, size);
234             break;
235         default:
236             break;
237     }
238 }
239 
240 static void goep_client_handle_sdp_query_end_of_record(goep_client_t * goep_client){
241     if (goep_client->uuid == BLUETOOTH_SERVICE_CLASS_MESSAGE_ACCESS_SERVER){
242         if (goep_client->mas_info.instance_id == goep_client->map_mas_instance_id){
243             // Requested MAS Instance found, accept info
244             log_info("MAS Instance #%u found", goep_client->map_mas_instance_id);
245             goep_client->rfcomm_port = goep_client->mas_info.rfcomm_port;
246             goep_client->profile_supported_features = goep_client->mas_info.supported_features;
247             goep_client->map_supported_message_types = goep_client->mas_info.supported_message_types;
248 #ifdef ENABLE_GOEP_L2CAP
249             goep_client->l2cap_psm = goep_client->mas_info.l2cap_psm;
250 #endif
251         }
252     }
253 }
254 static uint8_t goep_client_start_connect(goep_client_t * goep_client){
255 #ifdef ENABLE_GOEP_L2CAP
256     if (goep_client->l2cap_psm){
257         log_info("Remote GOEP L2CAP PSM: %u", goep_client->l2cap_psm);
258         return l2cap_ertm_create_channel(&goep_client_packet_handler, goep_client->bd_addr, goep_client->l2cap_psm,
259         &goep_client->ertm_config, goep_client->ertm_buffer,
260         goep_client->ertm_buffer_size, &goep_client->bearer_cid);
261     }
262 #endif
263     log_info("Remote GOEP RFCOMM Server Channel: %u", goep_client->rfcomm_port);
264     return rfcomm_create_channel(&goep_client_packet_handler, goep_client->bd_addr, goep_client->rfcomm_port, &goep_client->bearer_cid);
265 }
266 
267 static void goep_client_handle_sdp_query_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
268     goep_client_t * goep_client = goep_client_sdp_active;
269     btstack_assert(goep_client != NULL);
270 
271     UNUSED(packet_type);
272     UNUSED(channel);
273     UNUSED(size);
274 
275     des_iterator_t des_list_it;
276     des_iterator_t prot_it;
277     uint8_t status;
278     uint16_t record_index;
279     bool goep_server_found;
280 
281     switch (hci_event_packet_get_type(packet)){
282         case SDP_EVENT_QUERY_ATTRIBUTE_VALUE:
283 
284             // detect new record
285             record_index = sdp_event_query_attribute_byte_get_record_id(packet);
286             if (record_index != goep_client->record_index){
287                 goep_client->record_index = record_index;
288                 goep_client_handle_sdp_query_end_of_record(goep_client);
289                 memset(&goep_client->mas_info, 0, sizeof(goep_client->mas_info));
290             }
291 
292             // check if relevant attribute
293             switch(sdp_event_query_attribute_byte_get_attribute_id(packet)){
294                 case BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST:
295                 case BLUETOOTH_ATTRIBUTE_PBAP_SUPPORTED_FEATURES:
296                 case BLUETOOTH_ATTRIBUTE_MAS_INSTANCE_ID:
297                 case BLUETOOTH_ATTRIBUTE_SUPPORTED_MESSAGE_TYPES:
298 #ifdef ENABLE_GOEP_L2CAP
299                 case BLUETOOTH_ATTRIBUTE_GOEP_L2CAP_PSM:
300 #endif
301                     break;
302                 default:
303                     return;
304             }
305 
306             // warn if attribute too large to fit in our buffer
307             if (sdp_event_query_attribute_byte_get_attribute_length(packet) > goep_client_sdp_query_attribute_value_buffer_size) {
308                 log_error("SDP attribute value size exceeded for attribute %x: available %d, required %d", sdp_event_query_attribute_byte_get_attribute_id(packet), goep_client_sdp_query_attribute_value_buffer_size, sdp_event_query_attribute_byte_get_attribute_length(packet));
309                 break;
310             }
311 
312             // store single byte
313             goep_client_sdp_query_attribute_value[sdp_event_query_attribute_byte_get_data_offset(packet)] = sdp_event_query_attribute_byte_get_data(packet);
314 
315             // wait until value fully received
316             if ((uint16_t)(sdp_event_query_attribute_byte_get_data_offset(packet)+1) != sdp_event_query_attribute_byte_get_attribute_length(packet)) break;
317 
318             // process attributes
319             switch(sdp_event_query_attribute_byte_get_attribute_id(packet)) {
320                 case BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST:
321                     for (des_iterator_init(&des_list_it, goep_client_sdp_query_attribute_value); des_iterator_has_more(&des_list_it); des_iterator_next(&des_list_it)) {
322                         uint8_t       *des_element;
323                         uint8_t       *element;
324                         uint32_t       uuid;
325 
326                         if (des_iterator_get_type(&des_list_it) != DE_DES) continue;
327 
328                         des_element = des_iterator_get_element(&des_list_it);
329                         des_iterator_init(&prot_it, des_element);
330 
331                         // first element is UUID
332                         element = des_iterator_get_element(&prot_it);
333                         if (de_get_element_type(element) != DE_UUID) continue;
334 
335                         uuid = de_get_uuid32(element);
336                         des_iterator_next(&prot_it);
337                         if (!des_iterator_has_more(&prot_it)) continue;
338 
339                         // second element is RFCOMM server channel or L2CAP PSM
340                         element = des_iterator_get_element(&prot_it);
341                         if (uuid == BLUETOOTH_PROTOCOL_RFCOMM){
342                             if (goep_client->uuid == BLUETOOTH_SERVICE_CLASS_MESSAGE_ACCESS_SERVER) {
343                                 goep_client->mas_info.rfcomm_port = element[de_get_header_size(element)];
344                             } else {
345                                 goep_client->rfcomm_port = element[de_get_header_size(element)];
346                             }
347                         }
348                     }
349                     break;
350 #ifdef ENABLE_GOEP_L2CAP
351                 case BLUETOOTH_ATTRIBUTE_GOEP_L2CAP_PSM:
352                     if (goep_client->uuid == BLUETOOTH_SERVICE_CLASS_MESSAGE_ACCESS_SERVER){
353                         de_element_get_uint16(goep_client_sdp_query_attribute_value, &goep_client->mas_info.l2cap_psm);
354                     } else {
355                         de_element_get_uint16(goep_client_sdp_query_attribute_value, &goep_client->l2cap_psm);
356                     }
357                     break;
358 #endif
359                 // BLUETOOTH_ATTRIBUTE_PBAP_SUPPORTED_FEATURES == BLUETOOTH_ATTRIBUTE_MAP_SUPPORTED_FEATURES == 0x0317
360                 case BLUETOOTH_ATTRIBUTE_PBAP_SUPPORTED_FEATURES:
361                     if (de_get_element_type(goep_client_sdp_query_attribute_value) != DE_UINT) break;
362                     if (de_get_size_type(goep_client_sdp_query_attribute_value) != DE_SIZE_32) break;
363                     if (goep_client->uuid == BLUETOOTH_SERVICE_CLASS_MESSAGE_ACCESS_SERVER) {
364                         goep_client->mas_info.supported_features  = big_endian_read_32(goep_client_sdp_query_attribute_value, de_get_header_size(goep_client_sdp_query_attribute_value));
365                     } else {
366                         goep_client->profile_supported_features  = big_endian_read_32(goep_client_sdp_query_attribute_value, de_get_header_size(goep_client_sdp_query_attribute_value));
367                     }
368                     break;
369 
370                 case BLUETOOTH_ATTRIBUTE_MAS_INSTANCE_ID:
371                     if (de_get_element_type(goep_client_sdp_query_attribute_value) != DE_UINT) break;
372                     if (de_get_size_type(goep_client_sdp_query_attribute_value) != DE_SIZE_8) break;
373                     goep_client->mas_info.instance_id = goep_client_sdp_query_attribute_value[de_get_header_size(goep_client_sdp_query_attribute_value)];
374                     break;
375 
376                 case BLUETOOTH_ATTRIBUTE_SUPPORTED_MESSAGE_TYPES:
377                     if (de_get_element_type(goep_client_sdp_query_attribute_value) != DE_UINT) break;
378                     if (de_get_size_type(goep_client_sdp_query_attribute_value) != DE_SIZE_8) break;
379                     goep_client->mas_info.supported_message_types = goep_client_sdp_query_attribute_value[de_get_header_size(goep_client_sdp_query_attribute_value)];
380                     break;
381 
382                 default:
383                     break;
384             }
385             break;
386 
387         case SDP_EVENT_QUERY_COMPLETE:
388             goep_client_sdp_active = NULL;
389             goep_client_handle_sdp_query_end_of_record(goep_client);
390             status = sdp_event_query_complete_get_status(packet);
391             if (status != ERROR_CODE_SUCCESS){
392                 log_info("GOEP client, SDP query failed 0x%02x", status);
393                 goep_client->state = GOEP_CLIENT_INIT;
394                 goep_client_emit_connected_event(goep_client, status);
395                 break;
396             }
397             goep_server_found = false;
398             if (goep_client->rfcomm_port != 0){
399                 goep_server_found = true;
400             }
401 #ifdef ENABLE_GOEP_L2CAP
402             if (goep_client->l2cap_psm != 0){
403                 goep_server_found = true;
404             }
405 #endif
406             if (goep_server_found == false){
407                 log_info("No GOEP RFCOMM or L2CAP server found");
408                 goep_client->state = GOEP_CLIENT_INIT;
409                 goep_client_emit_connected_event(goep_client, SDP_SERVICE_NOT_FOUND);
410                 break;
411             }
412             (void) goep_client_start_connect(goep_client);
413             break;
414 
415         default:
416             break;
417     }
418 }
419 
420 static uint8_t * goep_client_get_outgoing_buffer(goep_client_t * goep_client){
421     if (goep_client->l2cap_psm){
422         return goep_packet_buffer;
423     } else {
424         return rfcomm_get_outgoing_buffer();
425     }
426 }
427 
428 static uint16_t goep_client_get_outgoing_buffer_len(goep_client_t * goep_client){
429     if (goep_client->l2cap_psm){
430         return sizeof(goep_packet_buffer);
431     } else {
432         return rfcomm_get_max_frame_size(goep_client->bearer_cid);
433     }
434 }
435 
436 static void goep_client_packet_init(goep_client_t *goep_client, uint8_t opcode) {
437     if (goep_client->l2cap_psm != 0){
438     } else {
439         rfcomm_reserve_packet_buffer();
440     }
441     // store opcode for parsing of response
442     goep_client->obex_opcode = opcode;
443 }
444 
445 void goep_client_init(void){
446     goep_client_t * goep_client = &goep_client_singleton;
447     memset(goep_client, 0, sizeof(goep_client_t));
448     goep_client->state = GOEP_CLIENT_INIT;
449 }
450 
451 void goep_client_deinit(void){
452     goep_clients = NULL;
453     goep_client_cid = 0;
454     memset(&goep_client_singleton, 0, sizeof(goep_client_t));
455     memset(goep_client_sdp_query_attribute_value, 0, sizeof(goep_client_sdp_query_attribute_value));
456     memset(goep_packet_buffer, 0, sizeof(goep_packet_buffer));
457 }
458 
459 static void geop_client_sdp_query_start(void * context){
460     uint16_t goep_cid = (uint16_t)(uintptr_t) context;
461     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
462     if (context != NULL){
463         goep_client_sdp_active = goep_client;
464         sdp_client_query_uuid16(&goep_client_handle_sdp_query_event, goep_client->bd_addr,
465                                 goep_client->uuid);
466     }
467 }
468 
469 uint8_t
470 goep_client_connect(goep_client_t *goep_client, l2cap_ertm_config_t *l2cap_ertm_config, uint8_t *l2cap_ertm_buffer,
471                     uint16_t l2cap_ertm_buffer_size, btstack_packet_handler_t handler, bd_addr_t addr, uint16_t uuid,
472                     uint8_t instance_id, uint16_t *out_cid) {
473     // get new goep cid, skip 0x0000
474     goep_client_cid++;
475     if (goep_client_cid == 0) {
476         goep_client_cid = 1;
477     }
478 
479     // add to list
480     memset(goep_client, 0, sizeof(goep_client_t));
481     goep_client->state = GOEP_CLIENT_W4_SDP;
482     goep_client->cid = goep_client_cid;
483     goep_client->client_handler = handler;
484     goep_client->uuid = uuid;
485     goep_client->map_mas_instance_id = instance_id;
486     goep_client->profile_supported_features = PROFILE_FEATURES_NOT_PRESENT;
487     (void)memcpy(goep_client->bd_addr, addr, 6);
488     goep_client->sdp_query_request.callback = geop_client_sdp_query_start;
489     goep_client->sdp_query_request.context = (void *)(uintptr_t) goep_client->cid;
490     goep_client->obex_connection_id = OBEX_CONNECTION_ID_INVALID;
491 #ifdef ENABLE_GOEP_L2CAP
492     memcpy(&goep_client->ertm_config, l2cap_ertm_config, sizeof(l2cap_ertm_config_t));
493     goep_client->ertm_buffer_size = l2cap_ertm_buffer_size;
494     goep_client->ertm_buffer = l2cap_ertm_buffer;
495 #endif
496     btstack_linked_list_add(&goep_clients, (btstack_linked_item_t *) goep_client);
497 
498     // request sdp query
499     sdp_client_register_query_callback(&goep_client->sdp_query_request);
500 
501     *out_cid = goep_client->cid;
502     return ERROR_CODE_SUCCESS;
503 }
504 
505 #ifdef ENABLE_GOEP_L2CAP
506 uint8_t goep_client_connect_l2cap(goep_client_t *goep_client, l2cap_ertm_config_t *l2cap_ertm_config, uint8_t *l2cap_ertm_buffer,
507                           uint16_t l2cap_ertm_buffer_size, btstack_packet_handler_t handler, bd_addr_t addr, uint16_t l2cap_psm,
508                           uint16_t *out_cid){
509     // get new goep cid, skip 0x0000
510     goep_client_cid++;
511     if (goep_client_cid == 0) {
512         goep_client_cid = 1;
513     }
514 
515     // add to list
516     memset(goep_client, 0, sizeof(goep_client_t));
517     goep_client->state = GOEP_CLIENT_W4_SDP;
518     goep_client->cid = goep_client_cid;
519     goep_client->client_handler = handler;
520     goep_client->profile_supported_features = PROFILE_FEATURES_NOT_PRESENT;
521     (void)memcpy(goep_client->bd_addr, addr, 6);
522     goep_client->obex_connection_id = OBEX_CONNECTION_ID_INVALID;
523     memcpy(&goep_client->ertm_config, l2cap_ertm_config, sizeof(l2cap_ertm_config_t));
524     goep_client->ertm_buffer_size = l2cap_ertm_buffer_size;
525     goep_client->ertm_buffer = l2cap_ertm_buffer;
526     btstack_linked_list_add(&goep_clients, (btstack_linked_item_t *) goep_client);
527 
528     goep_client->l2cap_psm = l2cap_psm;
529 
530     *out_cid = goep_client->cid;
531 
532     return goep_client_start_connect(goep_client);
533 }
534 #endif
535 
536 uint8_t goep_client_create_connection(btstack_packet_handler_t handler, bd_addr_t addr, uint16_t uuid, uint16_t * out_cid){
537     goep_client_t * goep_client = &goep_client_singleton;
538     if (goep_client->state != GOEP_CLIENT_INIT) {
539         return BTSTACK_MEMORY_ALLOC_FAILED;
540     }
541 #ifdef ENABLE_GOEP_L2CAP
542     return goep_client_connect(goep_client, &goep_client_singleton_ertm_config, goep_client_singleton_ertm_buffer,
543                                sizeof(goep_client_singleton_ertm_buffer), handler, addr, uuid, 0, out_cid);
544 #else
545     return goep_client_connect(goep_client, NULL, NULL,
546                                0, handler, addr, uuid, 0, out_cid);
547 #endif
548 
549 }
550 
551 uint32_t goep_client_get_pbap_supported_features(uint16_t goep_cid){
552     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
553     if (goep_client == NULL){
554         return PBAP_FEATURES_NOT_PRESENT;
555     }
556     return goep_client->profile_supported_features;
557 }
558 
559 uint32_t goep_client_get_map_supported_features(uint16_t goep_cid){
560     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
561     if (goep_client == NULL){
562         return PROFILE_FEATURES_NOT_PRESENT;
563     }
564     return goep_client->profile_supported_features;
565 }
566 
567 uint8_t goep_client_get_map_mas_instance_id(uint16_t goep_cid){
568     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
569     if (goep_client == NULL){
570         return 0;
571     }
572     return goep_client->map_mas_instance_id;
573 }
574 
575 uint8_t goep_client_get_map_supported_message_types(uint16_t goep_cid){
576     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
577     if (goep_client == NULL){
578         return 0;
579     }
580     return goep_client->map_supported_message_types;
581 }
582 
583 
584 bool goep_client_version_20_or_higher(uint16_t goep_cid){
585     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
586     if (goep_client == NULL){
587         return false;
588     }
589     return goep_client->l2cap_psm != 0;
590 }
591 
592 void goep_client_request_can_send_now(uint16_t goep_cid){
593     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
594     if (goep_client == NULL){
595         return;
596     }
597     if (goep_client->l2cap_psm){
598         l2cap_request_can_send_now_event(goep_client->bearer_cid);
599     } else {
600         rfcomm_request_can_send_now_event(goep_client->bearer_cid);
601     }
602 }
603 
604 uint8_t goep_client_disconnect(uint16_t goep_cid){
605     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
606     if (goep_client == NULL){
607         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
608     }
609     if (goep_client->l2cap_psm){
610         l2cap_disconnect(goep_client->bearer_cid);
611     } else {
612         rfcomm_disconnect(goep_client->bearer_cid);
613     }
614     return ERROR_CODE_SUCCESS;
615 }
616 
617 void goep_client_set_connection_id(uint16_t goep_cid, uint32_t connection_id){
618     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
619     if (goep_client == NULL){
620         return;
621     }
622     goep_client->obex_connection_id = connection_id;
623 }
624 
625 uint8_t goep_client_get_request_opcode(uint16_t goep_cid){
626     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
627     if (goep_client == NULL){
628         return 0;
629     }
630     return goep_client->obex_opcode;
631 }
632 
633 void goep_client_request_create_connect(uint16_t goep_cid, uint8_t obex_version_number, uint8_t flags, uint16_t maximum_obex_packet_length){
634     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
635     if (goep_client == NULL){
636         return;
637     }
638     goep_client_packet_init(goep_client, OBEX_OPCODE_CONNECT);
639     // workaround: limit OBEX packet len to L2CAP/RFCOMM MTU to avoid handling of fragemented packets
640     maximum_obex_packet_length = btstack_min(maximum_obex_packet_length, goep_client->bearer_mtu);
641 
642     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
643     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
644     obex_message_builder_request_create_connect(buffer, buffer_len, obex_version_number, flags, maximum_obex_packet_length);
645 }
646 
647 void goep_client_request_create_get(uint16_t goep_cid){
648     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
649     if (goep_client == NULL){
650         return;
651     }
652     goep_client_packet_init(goep_client, OBEX_OPCODE_GET | OBEX_OPCODE_FINAL_BIT_MASK);
653     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
654     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
655     obex_message_builder_request_create_get(buffer, buffer_len, goep_client->obex_connection_id);
656 }
657 
658 void goep_client_request_create_put(uint16_t goep_cid){
659     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
660     if (goep_client == NULL){
661         return;
662     }
663     goep_client_packet_init(goep_client, OBEX_OPCODE_PUT | OBEX_OPCODE_FINAL_BIT_MASK);
664     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
665     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
666     obex_message_builder_request_create_put(buffer, buffer_len, goep_client->obex_connection_id);
667 }
668 
669 void goep_client_request_create_set_path(uint16_t goep_cid, uint8_t flags){
670     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
671     if (goep_client == NULL){
672         return;
673     }
674     goep_client_packet_init(goep_client, OBEX_OPCODE_SETPATH);
675     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
676     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
677     obex_message_builder_request_create_set_path(buffer, buffer_len, flags, goep_client->obex_connection_id);
678 }
679 
680 void goep_client_request_create_abort(uint16_t goep_cid){
681     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
682     if (goep_client == NULL){
683         return;
684     }
685     goep_client_packet_init(goep_client, OBEX_OPCODE_ABORT);
686 
687     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
688     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
689     obex_message_builder_request_create_abort(buffer, buffer_len, goep_client->obex_connection_id);
690 }
691 
692 void goep_client_request_create_disconnect(uint16_t goep_cid){
693     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
694     if (goep_client == NULL){
695         return;
696     }
697     goep_client_packet_init(goep_client, OBEX_OPCODE_DISCONNECT);
698     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
699     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
700     obex_message_builder_request_create_disconnect(buffer, buffer_len, goep_client->obex_connection_id);
701 }
702 
703 void goep_client_header_add_byte(uint16_t goep_cid, uint8_t header_type, uint8_t value){
704     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
705     if (goep_client == NULL){
706         return;
707     }
708     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
709     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
710     obex_message_builder_header_add_byte(buffer, buffer_len, header_type, value);
711 }
712 
713 void goep_client_header_add_word(uint16_t goep_cid, uint8_t header_type, uint32_t value){
714     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
715     if (goep_client == NULL){
716         return;
717     }
718     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
719     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
720     obex_message_builder_header_add_word(buffer, buffer_len, header_type, value);
721 }
722 
723 void goep_client_header_add_variable(uint16_t goep_cid, uint8_t header_type, const uint8_t * header_data, uint16_t header_data_length){
724     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
725     if (goep_client == NULL){
726         return;
727     }
728     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
729     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
730     obex_message_builder_header_add_variable(buffer, buffer_len, header_type, header_data, header_data_length);
731 }
732 
733 void goep_client_header_add_srm_enable(uint16_t goep_cid){
734     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
735     if (goep_client == NULL){
736         return;
737     }
738     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
739     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
740     obex_message_builder_header_add_srm_enable(buffer, buffer_len);
741 }
742 
743 void goep_client_header_add_target(uint16_t goep_cid, const uint8_t * target, uint16_t length){
744     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
745     if (goep_client == NULL){
746         return;
747     }
748     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
749     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
750     obex_message_builder_header_add_target(buffer, buffer_len, target, length);
751 }
752 
753 void goep_client_header_add_application_parameters(uint16_t goep_cid, const uint8_t * data, uint16_t length){
754     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
755     if (goep_client == NULL){
756         return;
757     }
758     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
759     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
760     obex_message_builder_header_add_application_parameters(buffer, buffer_len, data, length);
761 }
762 
763 void goep_client_header_add_challenge_response(uint16_t goep_cid, const uint8_t * data, uint16_t length){
764     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
765     if (goep_client == NULL){
766         return;
767     }
768     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
769     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
770     obex_message_builder_header_add_challenge_response(buffer, buffer_len, data, length);
771 }
772 
773 void goep_client_body_add_static(uint16_t goep_cid, const uint8_t * data, uint32_t length){
774     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
775     if (goep_client == NULL){
776         return;
777     }
778     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
779     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
780     obex_message_builder_body_add_static(buffer, buffer_len, data, length);
781 }
782 
783 uint16_t goep_client_body_get_outgoing_buffer_len(uint16_t goep_cid) {
784     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
785     if (goep_client == NULL){
786         return 0;
787     }
788     return goep_client_get_outgoing_buffer_len(goep_client);
789 };
790 
791 void goep_client_body_fillup_static(uint16_t goep_cid, const uint8_t * data, uint32_t length, uint32_t * ret_length){
792     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
793     if (goep_client == NULL){
794         return;
795     }
796     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
797     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
798     obex_message_builder_body_fillup_static(buffer, buffer_len, data, length, ret_length);
799 }
800 
801 void goep_client_header_add_name(uint16_t goep_cid, const char * name){
802     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
803     if (goep_client == NULL){
804         return;
805     }
806     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
807     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
808     obex_message_builder_header_add_name(buffer, buffer_len, name);
809 }
810 
811 void goep_client_header_add_name_prefix(uint16_t goep_cid, const char * name, uint16_t name_len){
812     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
813     if (goep_client == NULL){
814         return;
815     }
816     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
817     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
818     obex_message_builder_header_add_name_prefix(buffer, buffer_len, name, name_len);
819 }
820 
821 void goep_client_header_add_unicode_prefix(uint16_t goep_cid, uint8_t header_id, const char * name, uint16_t name_len){
822     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
823     if (goep_client == NULL){
824         return;
825     }
826     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
827     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
828     obex_message_builder_header_add_unicode_prefix(buffer, buffer_len, header_id, name, name_len);
829 }
830 
831 void goep_client_header_add_type(uint16_t goep_cid, const char * type){
832     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
833     if (goep_client == NULL){
834         return;
835     }
836     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
837     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
838     obex_message_builder_header_add_type(buffer, buffer_len, type);
839 }
840 
841 void goep_client_header_add_length(uint16_t goep_cid, uint32_t length){
842     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
843     if (goep_client == NULL){
844         return;
845     }
846     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
847     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
848     obex_message_builder_header_add_length(buffer, buffer_len, length);
849 }
850 
851 uint16_t goep_client_request_get_max_body_size(uint16_t goep_cid){
852     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
853     if (goep_client == NULL){
854         return 0;
855     }
856     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
857     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
858     uint16_t pos = big_endian_read_16(buffer, 1);
859     return buffer_len - pos;
860 }
861 
862 int goep_client_execute(uint16_t goep_cid){
863     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
864     if (goep_client == NULL){
865         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
866     }
867     return goep_client_execute_with_final_bit (goep_cid, true);
868 }
869 
870 int goep_client_execute_with_final_bit(uint16_t goep_cid, bool final){
871     goep_client_t * goep_client = goep_client_for_cid(goep_cid);
872     if (goep_client == NULL){
873         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
874     }
875     uint8_t * buffer = goep_client_get_outgoing_buffer(goep_client);
876     uint16_t buffer_len = goep_client_get_outgoing_buffer_len(goep_client);
877 
878     obex_message_builder_set_final_bit (buffer, buffer_len, final);
879 
880     uint16_t pos = big_endian_read_16(buffer, 1);
881     if (goep_client->l2cap_psm){
882         return l2cap_send(goep_client->bearer_cid, buffer, pos);
883     } else {
884         return rfcomm_send_prepared(goep_client->bearer_cid, pos);
885     }
886 }
887 
888