xref: /btstack/src/classic/obex_iterator.c (revision d58a1b5f11ada8ddf896c41fff5a35e7f140c37e)
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 #include "hci_cmd.h"
46 #include "btstack_debug.h"
47 #include "hci.h"
48 #include "bluetooth_sdp.h"
49 #include "classic/sdp_client_rfcomm.h"
50 #include "btstack_event.h"
51 
52 #include "classic/obex.h"
53 #include "classic/obex_iterator.h"
54 
55 static int obex_packet_header_offset_for_opcode(uint8_t opcode){
56     switch (opcode){
57         case OBEX_OPCODE_SETPATH:
58             return 5;
59         case OBEX_OPCODE_CONNECT:
60             return 7;
61         default:
62             return 3;
63     }
64 }
65 
66 static void obex_iterator_init(obex_iterator_t *context, int header_offset, const uint8_t * packet_data, uint16_t packet_len){
67     memset(context, 0, sizeof(obex_iterator_t));
68     context->data   = packet_data + header_offset;
69     context->length = packet_len  - header_offset;
70 }
71 
72 void obex_iterator_init_with_request_packet(obex_iterator_t *context, const uint8_t * packet_data, uint16_t packet_len){
73     int header_offset = obex_packet_header_offset_for_opcode(packet_data[0]);
74     obex_iterator_init(context, header_offset, packet_data, packet_len);
75 }
76 
77 void obex_iterator_init_with_response_packet(obex_iterator_t *context, uint8_t request_opcode, const uint8_t * packet_data, uint16_t packet_len){
78     int header_offset = (request_opcode == OBEX_OPCODE_CONNECT) ? 7 : 3;
79     obex_iterator_init(context, header_offset, packet_data, packet_len);
80 }
81 
82 int  obex_iterator_has_more(const obex_iterator_t * context){
83     return context->offset < context->length;
84 }
85 
86 void obex_iterator_next(obex_iterator_t * context){
87     int len = 0;
88     const uint8_t * data = context->data + context->offset;
89     int encoding = data[0] >> 6;
90     switch (encoding){
91         case 0:
92         case 1:
93             // 16-bit length info prefixed
94             len = big_endian_read_16(data, 1);
95             break;
96         case 2:
97             // 8-bit value
98             len = 2;
99             break;
100         case 3:
101             // 32-bit value
102             len = 5;
103             break;
104         // avoid compiler warning about unused cases (by unclever compilers)
105         default:
106             break;
107     }
108     context->offset += len;
109 }
110 
111 // OBEX packet header access functions
112 
113 // @note BODY/END-OF-BODY headers might be incomplete
114 uint8_t         obex_iterator_get_hi(const obex_iterator_t * context){
115     return context->data[context->offset];
116 }
117 uint8_t         obex_iterator_get_data_8(const obex_iterator_t * context){
118     return context->data[context->offset+1];
119 }
120 uint32_t        obex_iterator_get_data_32(const obex_iterator_t * context){
121     return big_endian_read_32(context->data, context->offset + 1);
122 }
123 uint32_t        obex_iterator_get_data_len(const obex_iterator_t * context){
124     const uint8_t * data = context->data + context->offset;
125     int encoding = data[0] >> 6;
126     switch (encoding){
127         case 0:
128         case 1:
129             // 16-bit length info prefixed
130             return big_endian_read_16(data, 1) - 3;
131         case 2:
132             // 8-bit value
133             return 1;
134         case 3:
135             // 32-bit value
136             return 4;
137         // avoid compiler warning about unused cases (by unclever compilers)
138         default:
139             return 0;
140     }
141 }
142 
143 const uint8_t * obex_iterator_get_data(const obex_iterator_t * context){
144     const uint8_t * data = context->data + context->offset;
145     int encoding = data[0] >> 6;
146     switch (encoding){
147         case 0:
148         case 1:
149             // 16-bit length info prefixed
150             return &data[3];
151         default:
152             // 8-bit value
153             // 32-bit value
154             return &data[1];
155     }
156 }
157 
158 void obex_dump_packet(uint8_t request_opcode, uint8_t * packet, uint16_t size){
159     obex_iterator_t it;
160     printf("OBEX Opcode: 0x%02x\n", request_opcode);
161     int header_offset = (request_opcode == OBEX_OPCODE_CONNECT) ? 7 : 3;
162     printf("OBEX Header: ");
163     printf_hexdump(packet, header_offset);
164     for (obex_iterator_init_with_response_packet(&it, request_opcode, packet, size); obex_iterator_has_more(&it) ; obex_iterator_next(&it)){
165         uint8_t hi = obex_iterator_get_hi(&it);
166         printf("HI: %x - ", hi);
167         uint8_t encoding = hi >> 6;
168         uint16_t len;
169         switch (encoding){
170             case 0:
171             case 1:
172                 len = obex_iterator_get_data_len(&it);
173                 printf_hexdump(obex_iterator_get_data(&it), len);
174                 break;
175             case 2:
176                 printf("%02x\n", obex_iterator_get_data_8(&it));
177                 break;
178             case 3:
179                 printf("%08x\n", (int) obex_iterator_get_data_32(&it));
180                 break;
181         }
182 
183     }
184 }
185