xref: /btstack/src/ad_parser.c (revision 9192020a6656c4bc46feb4a63ee628096661bb3b)
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__ "ad_parser.c"
39 
40 
41 // *****************************************************************************
42 //
43 // Advertising Data Parser
44 //
45 // *****************************************************************************
46 
47 #include <stdint.h>
48 #include <string.h>
49 
50 #include "bluetooth_data_types.h"
51 #include "btstack_util.h"
52 #include "classic/sdp_util.h"
53 #include "hci.h"
54 #include "hci_cmd.h"
55 
56 #include "ad_parser.h"
57 
58 void ad_iterator_init(ad_context_t *context, uint8_t ad_len, const uint8_t * ad_data){
59     context->data = ad_data;
60     context->length = ad_len;
61     context->offset = 0;
62 }
63 
64 bool ad_iterator_has_more(const ad_context_t * context){
65     // assert chunk_len and chunk_type are withing buffer
66     if ((context->offset+1) >= context->length) return false;
67 
68     // assert chunk_len > 0
69     int chunk_len = context->data[context->offset];
70     if (chunk_len == 0)                                    return false;
71 
72     // assert complete chunk fits into buffer
73     if ((context->offset + 1 + chunk_len) > context->length) return false;
74 
75     return true;
76 }
77 
78 // pre: ad_iterator_has_more() == 1
79 void ad_iterator_next(ad_context_t * context){
80     int chunk_len = context->data[context->offset];
81     context->offset += 1 + chunk_len;
82 }
83 
84 uint8_t   ad_iterator_get_data_len(const ad_context_t * context){
85     return context->data[context->offset] - 1;
86 }
87 
88 uint8_t   ad_iterator_get_data_type(const ad_context_t * context){
89     return context->data[context->offset + 1];
90 }
91 
92 const uint8_t * ad_iterator_get_data(const ad_context_t * context){
93     return &context->data[context->offset + 2];
94 }
95 
96 bool ad_data_contains_uuid16(uint8_t ad_len, const uint8_t * ad_data, uint16_t uuid16){
97     ad_context_t context;
98     ad_iterator_init(&context, ad_len, ad_data);
99     while ( ad_iterator_has_more(&context) ){
100         uint8_t data_type    = ad_iterator_get_data_type(&context);
101         uint8_t data_len     = ad_iterator_get_data_len(&context);
102         const uint8_t * data = ad_iterator_get_data(&context);
103 
104         int i;
105         uint8_t ad_uuid128[16], uuid128_bt[16];
106 
107         switch (data_type){
108             case BLUETOOTH_DATA_TYPE_INCOMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS:
109             case BLUETOOTH_DATA_TYPE_COMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS:
110                 for (i=0; (i+2) <= data_len; i+=2){
111                     uint16_t uuid = little_endian_read_16(data, i);
112                     if ( uuid == uuid16 ) return true;
113                 }
114                 break;
115             case BLUETOOTH_DATA_TYPE_INCOMPLETE_LIST_OF_128_BIT_SERVICE_CLASS_UUIDS:
116             case BLUETOOTH_DATA_TYPE_COMPLETE_LIST_OF_128_BIT_SERVICE_CLASS_UUIDS:
117                 uuid_add_bluetooth_prefix(ad_uuid128, uuid16);
118                 reverse_128(ad_uuid128, uuid128_bt);
119                 for (i=0; (i+16) <= data_len; i+=16){
120                     if (memcmp(uuid128_bt, &data[i], 16) == 0) return true;
121                 }
122                 break;
123             default:
124                 break;
125         }
126         ad_iterator_next(&context);
127     }
128     return false;
129 }
130 
131 bool ad_data_contains_uuid128(uint8_t ad_len, const uint8_t * ad_data, const uint8_t * uuid128){
132     ad_context_t context;
133     // input in big endian/network order, bluetooth data in little endian
134     uint8_t uuid128_le[16];
135     reverse_128(uuid128, uuid128_le);
136     ad_iterator_init(&context, ad_len, ad_data);
137     while ( ad_iterator_has_more(&context) ){
138         uint8_t data_type = ad_iterator_get_data_type(&context);
139         uint8_t data_len  = ad_iterator_get_data_len(&context);
140         const uint8_t * data = ad_iterator_get_data(&context);
141 
142         int i;
143         uint8_t ad_uuid128[16];
144 
145         switch (data_type){
146             case BLUETOOTH_DATA_TYPE_INCOMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS:
147             case BLUETOOTH_DATA_TYPE_COMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS:
148                 for (i=0; (i+2) <= data_len; i+=2){
149                     uint16_t uuid16 = little_endian_read_16(data, i);
150                     uuid_add_bluetooth_prefix(ad_uuid128, uuid16);
151 
152                     if (memcmp(ad_uuid128, uuid128_le, 16) == 0) return true;
153                 }
154 
155                 break;
156             case BLUETOOTH_DATA_TYPE_INCOMPLETE_LIST_OF_128_BIT_SERVICE_CLASS_UUIDS:
157             case BLUETOOTH_DATA_TYPE_COMPLETE_LIST_OF_128_BIT_SERVICE_CLASS_UUIDS:
158                 for (i=0; (i+16) <= data_len; i+=16){
159                     if (memcmp(uuid128_le, &data[i], 16) == 0) return true;
160                 }
161                 break;
162             default:
163                 break;
164         }
165         ad_iterator_next(&context);
166     }
167     return false;
168 }
169 
170