xref: /btstack/src/classic/pbap_client.c (revision 6092cabe85e7419afc3e75a672c3f2fbb43c0647)
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 MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define __BTSTACK_FILE__ "pbap_client.c"
39 
40 #include "btstack_config.h"
41 
42 #include <stdint.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 
47 #include "hci_cmd.h"
48 #include "btstack_run_loop.h"
49 #include "btstack_debug.h"
50 #include "hci.h"
51 #include "btstack_memory.h"
52 #include "hci_dump.h"
53 #include "l2cap.h"
54 #include "bluetooth_sdp.h"
55 #include "classic/sdp_client_rfcomm.h"
56 #include "btstack_event.h"
57 #include "md5.h"
58 #include "yxml.h"
59 
60 #include "classic/obex.h"
61 #include "classic/obex_iterator.h"
62 #include "classic/goep_client.h"
63 #include "classic/pbap_client.h"
64 
65 // 796135f0-f0c5-11d8-0966- 0800200c9a66
66 static const uint8_t pbap_uuid[] = { 0x79, 0x61, 0x35, 0xf0, 0xf0, 0xc5, 0x11, 0xd8, 0x09, 0x66, 0x08, 0x00, 0x20, 0x0c, 0x9a, 0x66};
67 
68 const char * pbap_phonebook_type = "x-bt/phonebook";
69 const char * pbap_phonebook_name = "pb.vcf";
70 
71 const char * pbap_vcard_listing_type = "x-bt/vcard-listing";
72 const char * pbap_vcard_listing_name = "pb";
73 
74 // default
75 static uint32_t pbap_supported_features = 0x0000;
76 
77 typedef enum {
78     PBAP_INIT = 0,
79     PBAP_W4_GOEP_CONNECTION,
80     PBAP_W2_SEND_CONNECT_REQUEST,
81     PBAP_W4_CONNECT_RESPONSE,
82     PBAP_W4_USER_AUTHENTICATION,
83     PBAP_W2_SEND_AUTHENTICATED_CONNECT,
84     PBAP_CONNECT_RESPONSE_RECEIVED,
85     PBAP_CONNECTED,
86     //
87     PBAP_W2_SEND_DISCONNECT_REQUEST,
88     PBAP_W4_DISCONNECT_RESPONSE,
89     //
90     PBAP_W2_PULL_PHONEBOOK,
91     PBAP_W4_PHONEBOOK,
92     PBAP_W2_SET_PATH_ROOT,
93     PBAP_W4_SET_PATH_ROOT_COMPLETE,
94     PBAP_W2_SET_PATH_ELEMENT,
95     PBAP_W4_SET_PATH_ELEMENT_COMPLETE,
96     PBAP_W2_GET_PHONEBOOK_SIZE,
97     PBAP_W4_GET_PHONEBOOK_SIZE_COMPLETE,
98     //
99     PBAP_W2_GET_CARD_LIST,
100     PBAP_W4_GET_CARD_LIST_COMPLETE,
101 
102 } pbap_state_t;
103 
104 typedef struct pbap_client {
105     pbap_state_t state;
106     uint16_t  cid;
107     bd_addr_t bd_addr;
108     hci_con_handle_t con_handle;
109     uint8_t   incoming;
110     uint16_t  goep_cid;
111     btstack_packet_handler_t client_handler;
112     const char * current_folder;
113     const char * phone_number;
114     uint16_t set_path_offset;
115     uint8_t  authentication_options;
116     uint16_t authentication_nonce[16];
117     const char * authentication_password;
118     yxml_t  xml_parser;
119     uint8_t xml_buffer[50];
120 } pbap_client_t;
121 
122 static pbap_client_t _pbap_client;
123 static pbap_client_t * pbap_client = &_pbap_client;
124 
125 static void pbap_client_emit_connected_event(pbap_client_t * context, uint8_t status){
126     uint8_t event[15];
127     int pos = 0;
128     event[pos++] = HCI_EVENT_PBAP_META;
129     pos++;  // skip len
130     event[pos++] = PBAP_SUBEVENT_CONNECTION_OPENED;
131     little_endian_store_16(event,pos,context->cid);
132     pos+=2;
133     event[pos++] = status;
134     memcpy(&event[pos], context->bd_addr, 6);
135     pos += 6;
136     little_endian_store_16(event,pos,context->con_handle);
137     pos += 2;
138     event[pos++] = context->incoming;
139     event[1] = pos - 2;
140     if (pos != sizeof(event)) log_error("goep_client_emit_connected_event size %u", pos);
141     context->client_handler(HCI_EVENT_PACKET, context->cid, &event[0], pos);
142 }
143 
144 static void pbap_client_emit_connection_closed_event(pbap_client_t * context){
145     uint8_t event[5];
146     int pos = 0;
147     event[pos++] = HCI_EVENT_PBAP_META;
148     pos++;  // skip len
149     event[pos++] = PBAP_SUBEVENT_CONNECTION_CLOSED;
150     little_endian_store_16(event,pos,context->cid);
151     pos+=2;
152     event[1] = pos - 2;
153     if (pos != sizeof(event)) log_error("pbap_client_emit_connection_closed_event size %u", pos);
154     context->client_handler(HCI_EVENT_PACKET, context->cid, &event[0], pos);
155 }
156 
157 static void pbap_client_emit_operation_complete_event(pbap_client_t * context, uint8_t status){
158     uint8_t event[6];
159     int pos = 0;
160     event[pos++] = HCI_EVENT_PBAP_META;
161     pos++;  // skip len
162     event[pos++] = PBAP_SUBEVENT_OPERATION_COMPLETED;
163     little_endian_store_16(event,pos,context->cid);
164     pos+=2;
165     event[pos++]= status;
166     event[1] = pos - 2;
167     if (pos != sizeof(event)) log_error("pbap_client_emit_can_send_now_event size %u", pos);
168     context->client_handler(HCI_EVENT_PACKET, context->cid, &event[0], pos);
169 }
170 
171 static void pbap_client_emit_phonebook_size_event(pbap_client_t * context, uint8_t status, uint16_t phonebook_size){
172     uint8_t event[8];
173     int pos = 0;
174     event[pos++] = HCI_EVENT_PBAP_META;
175     pos++;  // skip len
176     event[pos++] = PBAP_SUBEVENT_PHONEBOOK_SIZE;
177     little_endian_store_16(event,pos,context->cid);
178     pos+=2;
179     event[pos++] = status;
180     little_endian_store_16(event,pos, phonebook_size);
181     pos+=2;
182     event[1] = pos - 2;
183     if (pos != sizeof(event)) log_error("pbap_client_emit_phonebook_size_event size %u", pos);
184     context->client_handler(HCI_EVENT_PACKET, context->cid, &event[0], pos);
185 }
186 
187 static void pbap_client_emit_authentication_event(pbap_client_t * context, uint8_t options){
188     // split options
189     uint8_t user_id_required = options & 1 ? 1 : 0;
190     uint8_t full_access      = options & 2 ? 1 : 0;
191 
192     uint8_t event[7];
193     int pos = 0;
194     event[pos++] = HCI_EVENT_PBAP_META;
195     pos++;  // skip len
196     event[pos++] = PBAP_SUBEVENT_AUTHENTICATION_REQUEST;
197     little_endian_store_16(event,pos,context->cid);
198     pos+=2;
199     event[pos++] = user_id_required;
200     event[pos++] = full_access;
201     if (pos != sizeof(event)) log_error("pbap_client_emit_authentication_event size %u", pos);
202     context->client_handler(HCI_EVENT_PACKET, context->cid, &event[0], pos);
203 }
204 
205 static void pbap_client_emit_card_result_event(pbap_client_t * context, const char * name, const char * handle){
206     uint8_t event[5 + PBAP_MAX_NAME_LEN + PBAP_MAX_HANDLE_LEN];
207     int pos = 0;
208     event[pos++] = HCI_EVENT_PBAP_META;
209     pos++;  // skip len
210     event[pos++] = PBAP_SUBEVENT_CARD_RESULT;
211     little_endian_store_16(event,pos,context->cid);
212     pos+=2;
213     int name_len = btstack_min(PBAP_MAX_NAME_LEN, strlen(name));
214     event[pos++] = name_len;
215     memcpy(&event[pos], name, name_len);
216     pos += name_len;
217     int handle_len = btstack_min(PBAP_MAX_HANDLE_LEN, strlen(handle));
218     event[pos++] = handle_len;
219     memcpy(&event[pos], handle, handle_len);
220     pos += handle_len;
221     event[1] = pos - 2;
222     context->client_handler(HCI_EVENT_PACKET, context->cid, &event[0], pos);
223 }
224 
225 static const uint8_t collon = (uint8_t) ':';
226 
227 static void pbap_handle_can_send_now(void){
228     uint8_t  path_element[20];
229     uint16_t path_element_start;
230     uint16_t path_element_len;
231     uint8_t  application_parameters[PBAP_MAX_PHONE_NUMBER_LEN + 10];
232     uint8_t  challenge_response[36];
233     int i;
234     uint16_t phone_number_len;
235 
236     MD5_CTX md5_ctx;
237 
238     switch (pbap_client->state){
239         case PBAP_W2_SEND_CONNECT_REQUEST:
240             goep_client_create_connect_request(pbap_client->goep_cid, OBEX_VERSION, 0, OBEX_MAX_PACKETLEN_DEFAULT);
241             goep_client_add_header_target(pbap_client->goep_cid, 16, pbap_uuid);
242             // Mandatory if the PSE advertises a PbapSupportedFeatures attribute in its SDP record, else excluded.
243             if (goep_client_get_pbap_supported_features(pbap_client->goep_cid) != PBAP_FEATURES_NOT_PRESENT){
244                 application_parameters[0] = PBAP_APPLICATION_PARAMETER_PBAP_SUPPORTED_FEATURES;
245                 application_parameters[1] = 4;
246                 big_endian_store_32(application_parameters, 2, pbap_supported_features);
247                 goep_client_add_header_application_parameters(pbap_client->goep_cid, 6, &application_parameters[0]);
248             }
249             pbap_client->state = PBAP_W4_CONNECT_RESPONSE;
250             goep_client_execute(pbap_client->goep_cid);
251             break;
252         case PBAP_W2_SEND_AUTHENTICATED_CONNECT:
253             goep_client_create_connect_request(pbap_client->goep_cid, OBEX_VERSION, 0, OBEX_MAX_PACKETLEN_DEFAULT);
254             goep_client_add_header_target(pbap_client->goep_cid, 16, pbap_uuid);
255             // setup authentication challenge response
256             i = 0;
257             challenge_response[i++] = 0;  // Tag Digest
258             challenge_response[i++] = 16; // Len
259             // calculate md5
260             MD5_Init(&md5_ctx);
261             MD5_Update(&md5_ctx, pbap_client->authentication_nonce, 16);
262             MD5_Update(&md5_ctx, &collon, 1);
263             MD5_Update(&md5_ctx, pbap_client->authentication_password, strlen(pbap_client->authentication_password));
264             MD5_Final(&challenge_response[i], &md5_ctx);
265             i += 16;
266             challenge_response[i++] = 2;  // Tag Nonce
267             challenge_response[i++] = 16; // Len
268             memcpy(&challenge_response[i], pbap_client->authentication_nonce, 16);
269             i += 16;
270             goep_client_add_header_challenge_response(pbap_client->goep_cid, i, challenge_response);
271             pbap_client->state = PBAP_W4_CONNECT_RESPONSE;
272             goep_client_execute(pbap_client->goep_cid);
273             break;
274         case PBAP_W2_SEND_DISCONNECT_REQUEST:
275             goep_client_create_disconnect_request(pbap_client->goep_cid);
276             pbap_client->state = PBAP_W4_DISCONNECT_RESPONSE;
277             goep_client_execute(pbap_client->goep_cid);
278             return;
279         case PBAP_W2_PULL_PHONEBOOK:
280         case PBAP_W2_GET_PHONEBOOK_SIZE:
281             goep_client_create_get_request(pbap_client->goep_cid);
282             goep_client_add_header_type(pbap_client->goep_cid, pbap_phonebook_type);
283             goep_client_add_header_name(pbap_client->goep_cid, pbap_phonebook_name);
284             if (pbap_client->state == PBAP_W2_GET_PHONEBOOK_SIZE){
285                 // Regular TLV wih 1-byte len
286                 application_parameters[0] = PBAP_APPLICATION_PARAMETER_MAX_LIST_COUNT;
287                 application_parameters[1] = 2;
288                 big_endian_store_16(application_parameters, 2, 0);
289                 goep_client_add_header_application_parameters(pbap_client->goep_cid, 4, &application_parameters[0]);
290                 // state
291                 pbap_client->state = PBAP_W4_GET_PHONEBOOK_SIZE_COMPLETE;
292             } else {
293                 // state
294                 pbap_client->state = PBAP_W4_PHONEBOOK;
295             }
296             // send packet
297             goep_client_execute(pbap_client->goep_cid);
298             break;
299         case PBAP_W2_GET_CARD_LIST:
300             goep_client_create_get_request(pbap_client->goep_cid);
301             goep_client_add_header_type(pbap_client->goep_cid, pbap_vcard_listing_type);
302             goep_client_add_header_name(pbap_client->goep_cid, pbap_vcard_listing_name);
303             // Regular TLV wih 1-byte len
304             i = 0;
305             phone_number_len = btstack_min(PBAP_MAX_PHONE_NUMBER_LEN, strlen(pbap_client->phone_number));
306             application_parameters[i++] = PBAP_APPLICATION_PARAMETER_SEARCH_VALUE;
307             application_parameters[i++] = phone_number_len;
308             memcpy(&application_parameters[i], pbap_client->phone_number, phone_number_len);
309             i += phone_number_len;
310             application_parameters[i++] = PBAP_APPLICATION_PARAMETER_SEARCH_PROPERTY;
311             application_parameters[i++] = 1;
312             application_parameters[i++] = 0x01; // Number
313             goep_client_add_header_application_parameters(pbap_client->goep_cid, i, &application_parameters[0]);
314             pbap_client->state = PBAP_W4_GET_CARD_LIST_COMPLETE;
315             // send packet
316             goep_client_execute(pbap_client->goep_cid);
317             break;
318         case PBAP_W2_SET_PATH_ROOT:
319             goep_client_create_set_path_request(pbap_client->goep_cid, 1 << 1); // Don’t create directory
320             // On Android 4.2 Cyanogenmod, using "" as path fails
321             // goep_client_add_header_name(pbap_client->goep_cid, "");     // empty == /
322             // state
323             pbap_client->state = PBAP_W4_SET_PATH_ROOT_COMPLETE;
324             // send packet
325             goep_client_execute(pbap_client->goep_cid);
326             break;
327         case PBAP_W2_SET_PATH_ELEMENT:
328             // find '/' or '\0'
329             path_element_start = pbap_client->set_path_offset;
330             while (pbap_client->current_folder[pbap_client->set_path_offset] != '\0' &&
331                 pbap_client->current_folder[pbap_client->set_path_offset] != '/'){
332                 pbap_client->set_path_offset++;
333             }
334             // skip /
335             if (pbap_client->current_folder[pbap_client->set_path_offset] == '/'){
336                 pbap_client->set_path_offset++;
337             }
338             path_element_len = pbap_client->set_path_offset-path_element_start;
339             memcpy(path_element, &pbap_client->current_folder[path_element_start], path_element_len);
340             path_element[path_element_len] = 0;
341 
342             goep_client_create_set_path_request(pbap_client->goep_cid, 1 << 1); // Don’t create directory
343             goep_client_add_header_name(pbap_client->goep_cid, (const char *) path_element); // next element
344             // state
345             pbap_client->state = PBAP_W4_SET_PATH_ELEMENT_COMPLETE;
346             // send packet
347             goep_client_execute(pbap_client->goep_cid);
348             break;
349         default:
350             break;
351     }
352 }
353 
354 static void pbap_parse_authentication_challenge(pbap_client_t * context, const uint8_t * challenge_data, uint16_t challenge_len){
355     // printf("Challenge:  ");
356     // printf_hexdump(challenge_data, challenge_len);
357     int i;
358     // uint8_t charset_code = 0;
359     for (i=0 ; i<challenge_len ; ){
360         int tag = challenge_data[i];
361         int len = challenge_data[i + 1];
362         i += 2;
363         switch (tag) {
364             case 0:
365                 if (len != 0x10) {
366                     log_error("Invalid OBEX digest len %u", len);
367                     return;
368                 }
369                 memcpy(context->authentication_nonce, &challenge_data[i], 16);
370                 // printf("Nonce: ");
371                 // printf_hexdump(context->authentication_nonce, 16);
372                 break;
373             case 1:
374                 context->authentication_options = challenge_data[i];
375                 // printf("Options %u\n", context->authentication_options);
376                 break;
377             case 2:
378                 // TODO: handle charset
379                 // charset_code = challenge_data[i];
380                 break;
381         }
382         i += len;
383     }
384 }
385 
386 static void pbap_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
387 
388     UNUSED(channel); // ok: there is no channel
389     UNUSED(size);    // ok: handling own geop events
390 
391     obex_iterator_t it;
392     uint8_t status;
393     switch (packet_type){
394         case HCI_EVENT_PACKET:
395             switch (hci_event_packet_get_type(packet)) {
396                 case HCI_EVENT_GOEP_META:
397                     switch (hci_event_goep_meta_get_subevent_code(packet)){
398                         case GOEP_SUBEVENT_CONNECTION_OPENED:
399                             status = goep_subevent_connection_opened_get_status(packet);
400                             pbap_client->con_handle = goep_subevent_connection_opened_get_con_handle(packet);
401                             pbap_client->incoming = goep_subevent_connection_opened_get_incoming(packet);
402                             goep_subevent_connection_opened_get_bd_addr(packet, pbap_client->bd_addr);
403                             if (status){
404                                 log_info("pbap: connection failed %u", status);
405                                 pbap_client->state = PBAP_INIT;
406                                 pbap_client_emit_connected_event(pbap_client, status);
407                             } else {
408                                 log_info("pbap: connection established");
409                                 pbap_client->goep_cid = goep_subevent_connection_opened_get_goep_cid(packet);
410                                 pbap_client->state = PBAP_W2_SEND_CONNECT_REQUEST;
411                                 goep_client_request_can_send_now(pbap_client->goep_cid);
412                             }
413                             break;
414                         case GOEP_SUBEVENT_CONNECTION_CLOSED:
415                             if (pbap_client->state != PBAP_CONNECTED){
416                                 pbap_client_emit_operation_complete_event(pbap_client, OBEX_DISCONNECTED);
417                             }
418                             pbap_client->state = PBAP_INIT;
419                             pbap_client_emit_connection_closed_event(pbap_client);
420                             break;
421                         case GOEP_SUBEVENT_CAN_SEND_NOW:
422                             pbap_handle_can_send_now();
423                             break;
424                     }
425                     break;
426                 default:
427                     break;
428             }
429             break;
430         case GOEP_DATA_PACKET:
431             // TODO: handle chunked data
432             // obex_dump_packet(goep_client_get_request_opcode(pbap_client->goep_cid), packet, size);
433             switch (pbap_client->state){
434                 case PBAP_W4_CONNECT_RESPONSE:
435                     switch (packet[0]){
436                         case OBEX_RESP_SUCCESS:
437                             for (obex_iterator_init_with_response_packet(&it, goep_client_get_request_opcode(pbap_client->goep_cid), packet, size); obex_iterator_has_more(&it) ; obex_iterator_next(&it)){
438                                 uint8_t hi = obex_iterator_get_hi(&it);
439                                 if (hi == OBEX_HEADER_CONNECTION_ID){
440                                     goep_client_set_connection_id(pbap_client->goep_cid, obex_iterator_get_data_32(&it));
441                                 }
442                             }
443                             pbap_client->state = PBAP_CONNECTED;
444                             pbap_client_emit_connected_event(pbap_client, 0);
445                             break;
446                         case OBEX_RESP_UNAUTHORIZED:
447                             for (obex_iterator_init_with_response_packet(&it, goep_client_get_request_opcode(pbap_client->goep_cid), packet, size); obex_iterator_has_more(&it) ; obex_iterator_next(&it)){
448                                 uint8_t hi = obex_iterator_get_hi(&it);
449                                 if (hi == OBEX_HEADER_AUTHENTICATION_CHALLENGE){
450                                     pbap_parse_authentication_challenge(pbap_client, obex_iterator_get_data(&it), obex_iterator_get_data_len(&it));
451                                 }
452                             }
453                             pbap_client->state = PBAP_W4_USER_AUTHENTICATION;
454                             pbap_client_emit_authentication_event(pbap_client, pbap_client->authentication_options);
455                             break;
456                         default:
457                             log_info("pbap: obex connect failed, result 0x%02x", packet[0]);
458                             pbap_client->state = PBAP_INIT;
459                             pbap_client_emit_connected_event(pbap_client, OBEX_CONNECT_FAILED);
460                             break;
461                     }
462                     break;
463                 case PBAP_W4_DISCONNECT_RESPONSE:
464                         goep_client_disconnect(pbap_client->goep_cid);
465                         break;
466                 case PBAP_W4_SET_PATH_ROOT_COMPLETE:
467                 case PBAP_W4_SET_PATH_ELEMENT_COMPLETE:
468                     if (packet[0] == OBEX_RESP_SUCCESS){
469                         if (pbap_client->current_folder){
470                             pbap_client->state = PBAP_W2_SET_PATH_ELEMENT;
471                             goep_client_request_can_send_now(pbap_client->goep_cid);
472                         } else {
473                             pbap_client_emit_operation_complete_event(pbap_client, 0);
474                         }
475                     } else if (packet[0] == OBEX_RESP_NOT_FOUND){
476                         pbap_client->state = PBAP_CONNECTED;
477                         pbap_client_emit_operation_complete_event(pbap_client, OBEX_NOT_FOUND);
478                     } else {
479                         pbap_client->state = PBAP_CONNECTED;
480                         pbap_client_emit_operation_complete_event(pbap_client, OBEX_UNKNOWN_ERROR);
481                     }
482                     break;
483                 case PBAP_W4_PHONEBOOK:
484                     for (obex_iterator_init_with_response_packet(&it, goep_client_get_request_opcode(pbap_client->goep_cid), packet, size); obex_iterator_has_more(&it) ; obex_iterator_next(&it)){
485                         uint8_t hi = obex_iterator_get_hi(&it);
486                         if (hi == OBEX_HEADER_BODY || hi == OBEX_HEADER_END_OF_BODY){
487                             uint16_t     data_len = obex_iterator_get_data_len(&it);
488                             const uint8_t  * data =  obex_iterator_get_data(&it);
489                             pbap_client->client_handler(PBAP_DATA_PACKET, pbap_client->cid, (uint8_t *) data, data_len);
490                         }
491                     }
492                     switch(packet[0]){
493                         case OBEX_RESP_CONTINUE:
494                             pbap_client->state = PBAP_W2_PULL_PHONEBOOK;
495                             goep_client_request_can_send_now(pbap_client->goep_cid);
496                             break;
497                         case OBEX_RESP_SUCCESS:
498                             pbap_client->state = PBAP_CONNECTED;
499                             pbap_client_emit_operation_complete_event(pbap_client, 0);
500                             break;
501                         default:
502                             log_info("unexpected response 0x%02x", packet[0]);
503                             pbap_client->state = PBAP_CONNECTED;
504                             pbap_client_emit_operation_complete_event(pbap_client, OBEX_UNKNOWN_ERROR);
505                             break;
506                     }
507                     break;
508                 case PBAP_W4_GET_PHONEBOOK_SIZE_COMPLETE:
509                     pbap_client->state = PBAP_CONNECTED;
510                     if (packet[0] == OBEX_RESP_SUCCESS){
511                         int have_size = 0;
512                         uint16_t phonebook_size;
513                         for (obex_iterator_init_with_response_packet(&it, goep_client_get_request_opcode(pbap_client->goep_cid), packet, size); obex_iterator_has_more(&it) ; obex_iterator_next(&it)){
514                             uint8_t hi = obex_iterator_get_hi(&it);
515                             if (hi == OBEX_HEADER_APPLICATION_PARAMETERS){
516                                 uint16_t     data_len = obex_iterator_get_data_len(&it);
517                                 const uint8_t  * data =  obex_iterator_get_data(&it);
518                                 // iterate over application headers (TLV with 1 bytes len)
519                                 unsigned int i = 0;
520                                 while (i<data_len){
521                                     uint8_t tag = data[i++];
522                                     uint8_t len = data[i++];
523                                     if (tag == PBAP_APPLICATION_PARAMETER_PHONEBOOK_SIZE && len == 2){
524                                         have_size = 1;
525                                         phonebook_size = big_endian_read_16(data, i);
526                                     }
527                                     i+=len;
528                                 }
529                             }
530                         }
531                         if (have_size){
532                             pbap_client_emit_phonebook_size_event(pbap_client, 0, phonebook_size);
533                             break;
534                         }
535                     }
536                     pbap_client_emit_phonebook_size_event(pbap_client, OBEX_UNKNOWN_ERROR, 0);
537                     break;
538                 case PBAP_W4_GET_CARD_LIST_COMPLETE:
539                     switch (packet[0]){
540                         case OBEX_RESP_CONTINUE:
541                             pbap_client->state = PBAP_W2_GET_CARD_LIST;
542                             goep_client_request_can_send_now(pbap_client->goep_cid);
543                             break;
544                         case OBEX_RESP_SUCCESS:
545                             for (obex_iterator_init_with_response_packet(&it, goep_client_get_request_opcode(pbap_client->goep_cid), packet, size); obex_iterator_has_more(&it) ; obex_iterator_next(&it)){
546                                 uint8_t hi = obex_iterator_get_hi(&it);
547                                 if (hi == OBEX_HEADER_END_OF_BODY){
548                                     uint16_t     data_len = obex_iterator_get_data_len(&it);
549                                     const uint8_t  * data =  obex_iterator_get_data(&it);
550                                     // now try parsing it
551                                     yxml_init(&pbap_client->xml_parser, pbap_client->xml_buffer, sizeof(pbap_client->xml_buffer));
552                                     int card_found = 0;
553                                     int name_found = 0;
554                                     int handle_found = 0;
555                                     char name[PBAP_MAX_NAME_LEN];
556                                     char handle[PBAP_MAX_HANDLE_LEN];
557                                     name[0] = 0;
558                                     handle[0] = 0;
559                                     while (data_len--){
560                                         yxml_ret_t r = yxml_parse(&pbap_client->xml_parser, *data++);
561                                         switch (r){
562                                             case YXML_ELEMSTART:
563                                                 card_found = strcmp("card", pbap_client->xml_parser.elem) == 0;
564                                                 break;
565                                             case YXML_ELEMEND:
566                                                 if (card_found){
567                                                     pbap_client_emit_card_result_event(pbap_client, name, handle);
568                                                 }
569                                                 card_found = 0;
570                                                 break;
571                                             case YXML_ATTRSTART:
572                                                 if (!card_found) break;
573                                                 if (strcmp("name", pbap_client->xml_parser.attr) == 0){
574                                                     name_found = 1;
575                                                     break;
576                                                 }
577                                                 if (strcmp("handle", pbap_client->xml_parser.attr) == 0){
578                                                     handle_found = 1;
579                                                     break;
580                                                 }
581                                                 break;
582                                             case YXML_ATTRVAL:
583                                                 if (name_found) {
584                                                     // "In UTF-8, characters from the U+0000..U+10FFFF range (the UTF-16 accessible range) are encoded using sequences of 1 to 4 octets."
585                                                     if (strlen(name) + 4 + 1 >= sizeof(name)) break;
586                                                     strcat(name, pbap_client->xml_parser.data);
587                                                     break;
588                                                 }
589                                                 if (handle_found) {
590                                                     // "In UTF-8, characters from the U+0000..U+10FFFF range (the UTF-16 accessible range) are encoded using sequences of 1 to 4 octets."
591                                                     if (strlen(handle) + 4 + 1 >= sizeof(handle)) break;
592                                                     strcat(handle, pbap_client->xml_parser.data);
593                                                     break;
594                                                 }
595                                                 break;
596                                             case YXML_ATTREND:
597                                                 name_found = 0;
598                                                 handle_found = 0;
599                                                 break;
600                                             default:
601                                                 break;
602                                         }
603                                     }
604                                     //
605                                     pbap_client->state = PBAP_CONNECTED;
606                                     pbap_client_emit_operation_complete_event(pbap_client, 0);
607                                 }
608                             }
609                             break;
610                         case OBEX_RESP_NOT_ACCEPTABLE:
611                             pbap_client->state = PBAP_CONNECTED;
612                             pbap_client_emit_operation_complete_event(pbap_client, OBEX_NOT_ACCEPTABLE);
613                             break;
614                         default:
615                             log_info("unexpected response 0x%02x", packet[0]);
616                             pbap_client->state = PBAP_CONNECTED;
617                             pbap_client_emit_operation_complete_event(pbap_client, OBEX_UNKNOWN_ERROR);
618                             break;
619                     }
620                     break;
621                 default:
622                     break;
623             }
624             break;
625         default:
626             break;
627     }
628 }
629 
630 void pbap_client_init(void){
631     memset(pbap_client, 0, sizeof(pbap_client_t));
632     pbap_client->state = PBAP_INIT;
633     pbap_client->cid = 1;
634 }
635 
636 uint8_t pbap_connect(btstack_packet_handler_t handler, bd_addr_t addr, uint16_t * out_cid){
637     if (pbap_client->state != PBAP_INIT) return BTSTACK_MEMORY_ALLOC_FAILED;
638     pbap_client->state = PBAP_W4_GOEP_CONNECTION;
639     pbap_client->client_handler = handler;
640     uint8_t err = goep_client_create_connection(&pbap_packet_handler, addr, BLUETOOTH_SERVICE_CLASS_PHONEBOOK_ACCESS_PSE, &pbap_client->goep_cid);
641     *out_cid = pbap_client->cid;
642     if (err) return err;
643     return 0;
644 }
645 
646 uint8_t pbap_disconnect(uint16_t pbap_cid){
647     UNUSED(pbap_cid);
648     if (pbap_client->state != PBAP_CONNECTED) return BTSTACK_BUSY;
649     pbap_client->state = PBAP_W2_SEND_DISCONNECT_REQUEST;
650     goep_client_request_can_send_now(pbap_client->goep_cid);
651     return 0;
652 }
653 
654 uint8_t pbap_get_phonebook_size(uint16_t pbap_cid){
655     UNUSED(pbap_cid);
656     if (pbap_client->state != PBAP_CONNECTED) return BTSTACK_BUSY;
657     pbap_client->state = PBAP_W2_GET_PHONEBOOK_SIZE;
658     goep_client_request_can_send_now(pbap_client->goep_cid);
659     return 0;
660 }
661 
662 uint8_t pbap_pull_phonebook(uint16_t pbap_cid){
663     UNUSED(pbap_cid);
664     if (pbap_client->state != PBAP_CONNECTED) return BTSTACK_BUSY;
665     pbap_client->state = PBAP_W2_PULL_PHONEBOOK;
666     goep_client_request_can_send_now(pbap_client->goep_cid);
667     return 0;
668 }
669 
670 uint8_t pbap_set_phonebook(uint16_t pbap_cid, const char * path){
671     UNUSED(pbap_cid);
672     if (pbap_client->state != PBAP_CONNECTED) return BTSTACK_BUSY;
673     pbap_client->state = PBAP_W2_SET_PATH_ROOT;
674     pbap_client->current_folder = path;
675     pbap_client->set_path_offset = 0;
676     goep_client_request_can_send_now(pbap_client->goep_cid);
677     return 0;
678 }
679 
680 uint8_t pbap_authentication_password(uint16_t pbap_cid, const char * password){
681     UNUSED(pbap_cid);
682     if (pbap_client->state != PBAP_W4_USER_AUTHENTICATION) return BTSTACK_BUSY;
683     pbap_client->state = PBAP_W2_SEND_AUTHENTICATED_CONNECT;
684     pbap_client->authentication_password = password;
685     goep_client_request_can_send_now(pbap_client->goep_cid);
686     return 0;
687 }
688 
689 uint8_t pbap_lookup_by_number(uint16_t pbap_cid, const char * phone_number){
690     UNUSED(pbap_cid);
691     if (pbap_client->state != PBAP_CONNECTED) return BTSTACK_BUSY;
692     pbap_client->state = PBAP_W2_GET_CARD_LIST;
693     pbap_client->phone_number = phone_number;
694     goep_client_request_can_send_now(pbap_client->goep_cid);
695     return 0;
696 }
697