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__ "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
obex_packet_header_offset_for_opcode(uint8_t opcode)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
obex_iterator_reset(obex_iterator_t * context)70 static void obex_iterator_reset(obex_iterator_t *context){
71 memset(context, 0, sizeof(obex_iterator_t));
72 context->valid = false;
73 }
74
75 // check if num bytes are available, and if not, invalidate iterator
obex_iterator_check(obex_iterator_t * context,uint32_t num_bytes)76 static bool obex_iterator_check(obex_iterator_t *context, uint32_t num_bytes){
77 if ((context->offset + num_bytes) > context->length){
78 context->valid = false;
79 }
80 return context->valid;
81 }
82
obex_iterator_prepare(obex_iterator_t * context)83 static void obex_iterator_prepare(obex_iterator_t *context){
84 if (obex_iterator_check(context, 1) == false) return;
85 const uint8_t * data = context->data + context->offset;
86 uint8_t encoding = data[0] >> 6;
87 switch (encoding){
88 case 0:
89 case 1:
90 // 16-bit length info prefixed
91 if (obex_iterator_check(context, 3) == false) return;
92 context->data_size = big_endian_read_16(data, 1);
93 context->header_size = 3;
94 // length includes the header, remove from data size
95 if (context->data_size < 3){
96 context->valid = false;
97 return;
98 }
99 context->data_size -= 3;
100 break;
101 case 2:
102 // 8-bit value
103 context->data_size = 1;
104 context->header_size = 1;
105 break;
106 case 3:
107 // 32-bit value
108 context->data_size = 4;
109 context->header_size = 1;
110 break;
111 default:
112 // avoid compiler warning about unused cases (encoding in [0..3])
113 break;
114 }
115 (void) obex_iterator_check(context, context->header_size + context->data_size);
116 }
117
obex_iterator_init(obex_iterator_t * context,int header_offset,const uint8_t * packet_data,uint16_t packet_len)118 static void obex_iterator_init(obex_iterator_t *context, int header_offset, const uint8_t * packet_data, uint16_t packet_len){
119 if (header_offset >= packet_len) return;
120 context->data = packet_data + header_offset;
121 context->length = packet_len - header_offset;
122 context->valid = true;
123 obex_iterator_prepare(context);
124 }
125
obex_iterator_init_with_request_packet(obex_iterator_t * context,const uint8_t * packet_data,uint16_t packet_len)126 void obex_iterator_init_with_request_packet(obex_iterator_t *context, const uint8_t * packet_data, uint16_t packet_len){
127 obex_iterator_reset(context);
128 if (packet_len == 0) return;
129 int header_offset = obex_packet_header_offset_for_opcode(packet_data[0]);
130 obex_iterator_init(context, header_offset, packet_data, packet_len);
131 }
132
obex_iterator_init_with_response_packet(obex_iterator_t * context,uint8_t request_opcode,const uint8_t * packet_data,uint16_t packet_len)133 void obex_iterator_init_with_response_packet(obex_iterator_t *context, uint8_t request_opcode, const uint8_t * packet_data, uint16_t packet_len){
134 obex_iterator_reset(context);
135 int header_offset = (request_opcode == OBEX_OPCODE_CONNECT) ? 7 : 3;
136 obex_iterator_init(context, header_offset, packet_data, packet_len);
137 }
138
obex_iterator_has_more(const obex_iterator_t * context)139 int obex_iterator_has_more(const obex_iterator_t * context){
140 return context->valid;
141 }
142
obex_iterator_next(obex_iterator_t * context)143 void obex_iterator_next(obex_iterator_t * context){
144 if (context->valid == false) return;
145 context->offset += context->header_size + context->data_size;
146 obex_iterator_prepare(context);
147 }
148
149 // OBEX packet header access functions
150
151 // @note BODY/END-OF-BODY headers might be incomplete
obex_iterator_get_hi(const obex_iterator_t * context)152 uint8_t obex_iterator_get_hi(const obex_iterator_t * context){
153 return context->data[context->offset];
154 }
obex_iterator_get_data_8(const obex_iterator_t * context)155 uint8_t obex_iterator_get_data_8(const obex_iterator_t * context){
156 return context->data[context->offset+1];
157 }
obex_iterator_get_data_32(const obex_iterator_t * context)158 uint32_t obex_iterator_get_data_32(const obex_iterator_t * context){
159 return big_endian_read_32(context->data, context->offset + 1);
160 }
obex_iterator_get_data_len(const obex_iterator_t * context)161 uint32_t obex_iterator_get_data_len(const obex_iterator_t * context){
162 return context->data_size;
163 }
164
obex_iterator_get_data(const obex_iterator_t * context)165 const uint8_t * obex_iterator_get_data(const obex_iterator_t * context){
166 return &context->data[context->offset + context->header_size];
167 }
168
169 #ifdef ENABLE_OBEX_DUMP
obex_dump_packet(uint8_t request_opcode,uint8_t * packet,uint16_t size)170 void obex_dump_packet(uint8_t request_opcode, uint8_t * packet, uint16_t size){
171 obex_iterator_t it;
172 printf("OBEX Opcode: 0x%02x\n", request_opcode);
173 int header_offset = (request_opcode == OBEX_OPCODE_CONNECT) ? 7 : 3;
174 printf("OBEX Header: ");
175 printf_hexdump(packet, header_offset);
176 for (obex_iterator_init_with_response_packet(&it, request_opcode, packet, size); obex_iterator_has_more(&it) ; obex_iterator_next(&it)){
177 uint8_t hi = obex_iterator_get_hi(&it);
178 printf("HI: %x - ", hi);
179 uint8_t encoding = hi >> 6;
180 uint16_t len;
181 switch (encoding){
182 case 0:
183 case 1:
184 len = obex_iterator_get_data_len(&it);
185 printf_hexdump(obex_iterator_get_data(&it), len);
186 break;
187 case 2:
188 printf("%02x\n", obex_iterator_get_data_8(&it));
189 break;
190 case 3:
191 printf("%08x\n", (int) obex_iterator_get_data_32(&it));
192 break;
193 default:
194 btstack_assert(false);
195 break;
196 }
197
198 }
199 }
200 #endif
201