xref: /btstack/src/classic/obex_iterator.c (revision 3e90877db8cb17795c6b27a3cef2cb84d0aa93cf)
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__ "obex_iterator.c"
39 
40 #include "btstack_config.h"
41 
42 #include <stdint.h>
43 #include <stdlib.h>
44 
45 #ifdef ENABLE_OBEX_DUMP
46 #include <stdio.h>
47 #endif
48 
49 #include "hci_cmd.h"
50 #include "btstack_debug.h"
51 #include "hci.h"
52 #include "bluetooth_sdp.h"
53 #include "classic/sdp_client_rfcomm.h"
54 #include "btstack_event.h"
55 
56 #include "classic/obex.h"
57 #include "classic/obex_iterator.h"
58 
59 static int obex_packet_header_offset_for_opcode(uint8_t opcode){
60     switch (opcode){
61         case OBEX_OPCODE_SETPATH:
62             return 5;
63         case OBEX_OPCODE_CONNECT:
64             return 7;
65         default:
66             return 3;
67     }
68 }
69 
70 static void obex_iterator_init(obex_iterator_t *context, int header_offset, const uint8_t * packet_data, uint16_t packet_len){
71     memset(context, 0, sizeof(obex_iterator_t));
72     context->data   = packet_data + header_offset;
73     context->length = packet_len  - header_offset;
74 }
75 
76 void obex_iterator_init_with_request_packet(obex_iterator_t *context, const uint8_t * packet_data, uint16_t packet_len){
77     int header_offset = obex_packet_header_offset_for_opcode(packet_data[0]);
78     obex_iterator_init(context, header_offset, packet_data, packet_len);
79 }
80 
81 void obex_iterator_init_with_response_packet(obex_iterator_t *context, uint8_t request_opcode, const uint8_t * packet_data, uint16_t packet_len){
82     int header_offset = (request_opcode == OBEX_OPCODE_CONNECT) ? 7 : 3;
83     obex_iterator_init(context, header_offset, packet_data, packet_len);
84 }
85 
86 int  obex_iterator_has_more(const obex_iterator_t * context){
87     return context->offset < context->length;
88 }
89 
90 void obex_iterator_next(obex_iterator_t * context){
91     int len = 0;
92     const uint8_t * data = context->data + context->offset;
93     int encoding = data[0] >> 6;
94     switch (encoding){
95         case 0:
96         case 1:
97             // 16-bit length info prefixed
98             len = big_endian_read_16(data, 1);
99             break;
100         case 2:
101             // 8-bit value
102             len = 2;
103             break;
104         case 3:
105             // 32-bit value
106             len = 5;
107             break;
108         // avoid compiler warning about unused cases (by unclever compilers)
109         default:
110             break;
111     }
112     context->offset += len;
113 }
114 
115 // OBEX packet header access functions
116 
117 // @note BODY/END-OF-BODY headers might be incomplete
118 uint8_t         obex_iterator_get_hi(const obex_iterator_t * context){
119     return context->data[context->offset];
120 }
121 uint8_t         obex_iterator_get_data_8(const obex_iterator_t * context){
122     return context->data[context->offset+1];
123 }
124 uint32_t        obex_iterator_get_data_32(const obex_iterator_t * context){
125     return big_endian_read_32(context->data, context->offset + 1);
126 }
127 uint32_t        obex_iterator_get_data_len(const obex_iterator_t * context){
128     const uint8_t * data = context->data + context->offset;
129     int encoding = data[0] >> 6;
130     switch (encoding){
131         case 0:
132         case 1:
133             // 16-bit length info prefixed
134             return big_endian_read_16(data, 1) - 3;
135         case 2:
136             // 8-bit value
137             return 1;
138         case 3:
139             // 32-bit value
140             return 4;
141         // avoid compiler warning about unused cases (by unclever compilers)
142         default:
143             return 0;
144     }
145 }
146 
147 const uint8_t * obex_iterator_get_data(const obex_iterator_t * context){
148     const uint8_t * data = context->data + context->offset;
149     int encoding = data[0] >> 6;
150     switch (encoding){
151         case 0:
152         case 1:
153             // 16-bit length info prefixed
154             return &data[3];
155         default:
156             // 8-bit value
157             // 32-bit value
158             return &data[1];
159     }
160 }
161 
162 #ifdef ENABLE_OBEX_DUMP
163 void obex_dump_packet(uint8_t request_opcode, uint8_t * packet, uint16_t size){
164     obex_iterator_t it;
165     printf("OBEX Opcode: 0x%02x\n", request_opcode);
166     int header_offset = (request_opcode == OBEX_OPCODE_CONNECT) ? 7 : 3;
167     printf("OBEX Header: ");
168     printf_hexdump(packet, header_offset);
169     for (obex_iterator_init_with_response_packet(&it, request_opcode, packet, size); obex_iterator_has_more(&it) ; obex_iterator_next(&it)){
170         uint8_t hi = obex_iterator_get_hi(&it);
171         printf("HI: %x - ", hi);
172         uint8_t encoding = hi >> 6;
173         uint16_t len;
174         switch (encoding){
175             case 0:
176             case 1:
177                 len = obex_iterator_get_data_len(&it);
178                 printf_hexdump(obex_iterator_get_data(&it), len);
179                 break;
180             case 2:
181                 printf("%02x\n", obex_iterator_get_data_8(&it));
182                 break;
183             case 3:
184                 printf("%08x\n", (int) obex_iterator_get_data_32(&it));
185                 break;
186             default:
187                 btstack_assert(false);
188                 break;
189         }
190 
191     }
192 }
193 #endif
194