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__ "btstack_link_key_db_fs.c"
39
40 #include <string.h>
41 #include <stdlib.h>
42 #include <stdio.h>
43 #include <unistd.h>
44
45 #include "tinydir.h"
46
47 #include "btstack_config.h"
48 #include "btstack_link_key_db_fs.h"
49 #include "btstack_debug.h"
50 #include "btstack_util.h"
51
52 // allow to pre-set LINK_KEY_PATH from btstack_config.h
53 #ifndef LINK_KEY_PATH
54 #ifdef _WIN32
55 #define LINK_KEY_PATH ""
56 #else
57 #define LINK_KEY_PATH "/tmp/"
58 #endif
59 #endif
60
61 #define LINK_KEY_PREFIX "btstack_at_"
62 #define LINK_KEY_FOR "_link_key_for_"
63 #define LINK_KEY_SUFFIX ".txt"
64 #define LINK_KEY_STRING_LEN 17
65
66 static bd_addr_t local_addr;
67 // note: sizeof for string literals works at compile time while strlen only works with some optimizations turned on. sizeof includes the \0
68 static char keypath[sizeof(LINK_KEY_PATH) + sizeof(LINK_KEY_PREFIX) + LINK_KEY_STRING_LEN + sizeof(LINK_KEY_FOR) + LINK_KEY_STRING_LEN + sizeof(LINK_KEY_SUFFIX) + 1];
69
bd_addr_to_dash_str(bd_addr_t addr)70 static char * bd_addr_to_dash_str(bd_addr_t addr){
71 return bd_addr_to_str_with_delimiter(addr, '-');
72 }
73
74 static char link_key_to_str_buffer[LINK_KEY_STR_LEN+1]; // 11223344556677889900112233445566\0
link_key_to_str(link_key_t link_key)75 static char *link_key_to_str(link_key_t link_key){
76 char * p = link_key_to_str_buffer;
77 int i;
78 for (i = 0; i < LINK_KEY_LEN ; i++) {
79 *p++ = char_for_nibble((link_key[i] >> 4) & 0x0F);
80 *p++ = char_for_nibble((link_key[i] >> 0) & 0x0F);
81 }
82 *p = 0;
83 return (char *) link_key_to_str_buffer;
84 }
85
86 static char link_key_type_to_str_buffer[2];
link_key_type_to_str(link_key_type_t link_key)87 static char *link_key_type_to_str(link_key_type_t link_key){
88 btstack_snprintf_assert_complete(link_key_type_to_str_buffer, sizeof(link_key_type_to_str_buffer), "%d", link_key);
89 return (char *) link_key_type_to_str_buffer;
90 }
91
sscanf_link_key(char * addr_string,link_key_t link_key)92 static int sscanf_link_key(char * addr_string, link_key_t link_key){
93 unsigned int buffer[LINK_KEY_LEN];
94
95 // reset result buffer
96 memset(&buffer, 0, sizeof(buffer));
97
98 // parse
99 int result = sscanf( (char *) addr_string, "%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x",
100 &buffer[0], &buffer[1], &buffer[2], &buffer[3],
101 &buffer[4], &buffer[5], &buffer[6], &buffer[7],
102 &buffer[8], &buffer[9], &buffer[10], &buffer[11],
103 &buffer[12], &buffer[13], &buffer[14], &buffer[15] );
104
105 if (result != LINK_KEY_LEN) return 0;
106
107 // store
108 int i;
109 uint8_t *p = (uint8_t *) link_key;
110 for (i=0; i<LINK_KEY_LEN; i++ ) {
111 *p++ = (uint8_t) buffer[i];
112 }
113 return 1;
114 }
115
set_path(bd_addr_t bd_addr)116 static void set_path(bd_addr_t bd_addr){
117 strcpy(keypath, LINK_KEY_PATH);
118 strcat(keypath, LINK_KEY_PREFIX);
119 strcat(keypath, bd_addr_to_dash_str(local_addr));
120 strcat(keypath, LINK_KEY_FOR);
121 strcat(keypath, bd_addr_to_dash_str(bd_addr));
122 strcat(keypath, LINK_KEY_SUFFIX);
123 }
124
125 // Device info
db_open(void)126 static void db_open(void){
127 }
128
db_set_local_bd_addr(bd_addr_t bd_addr)129 static void db_set_local_bd_addr(bd_addr_t bd_addr){
130 memcpy(local_addr, bd_addr, 6);
131 }
132
db_close(void)133 static void db_close(void){
134 }
135
put_link_key(bd_addr_t bd_addr,link_key_t link_key,link_key_type_t link_key_type)136 static void put_link_key(bd_addr_t bd_addr, link_key_t link_key, link_key_type_t link_key_type){
137 set_path(bd_addr);
138 char * link_key_str = link_key_to_str(link_key);
139 char * link_key_type_str = link_key_type_to_str(link_key_type);
140
141 FILE * wFile = fopen(keypath,"w+");
142 if (wFile == NULL){
143 log_error("failed to create file");
144 return;
145 }
146 fwrite(link_key_str, strlen(link_key_str), 1, wFile);
147 fwrite(link_key_type_str, strlen(link_key_type_str), 1, wFile);
148 fclose(wFile);
149 }
150
read_link_key(const char * path,link_key_t link_key,link_key_type_t * link_key_type)151 static int read_link_key(const char * path, link_key_t link_key, link_key_type_t * link_key_type){
152 if (access(path, R_OK)) return 0;
153
154 char link_key_str[LINK_KEY_STR_LEN + 1];
155 char link_key_type_str[2];
156
157 FILE * rFile = fopen(path,"r+");
158 if (rFile == NULL) return 0;
159 size_t objects_read = fread(link_key_str, LINK_KEY_STR_LEN, 1, rFile );
160 if (objects_read == 1){
161 link_key_str[LINK_KEY_STR_LEN] = 0;
162 log_info("Found link key %s\n", link_key_str);
163 objects_read = fread(link_key_type_str, 1, 1, rFile );
164 }
165 fclose(rFile);
166
167 if (objects_read != 1) return 0;
168 link_key_type_str[1] = 0;
169 log_info("Found link key type %s\n", link_key_type_str);
170
171 int scan_result = sscanf_link_key(link_key_str, link_key);
172 if (scan_result == 0 ) return 0;
173
174 int link_key_type_buffer;
175 scan_result = sscanf( (char *) link_key_type_str, "%d", &link_key_type_buffer);
176 if (scan_result == 0 ) return 0;
177 *link_key_type = (link_key_type_t) link_key_type_buffer;
178 return 1;
179 }
180
get_link_key(bd_addr_t bd_addr,link_key_t link_key,link_key_type_t * link_key_type)181 static int get_link_key(bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * link_key_type) {
182 set_path(bd_addr);
183 return read_link_key(keypath, link_key, link_key_type);
184 }
185
delete_link_key(bd_addr_t bd_addr)186 static void delete_link_key(bd_addr_t bd_addr){
187 set_path(bd_addr);
188 if (access(keypath, R_OK)) return;
189 if(remove(keypath) != 0){
190 log_error("File %s could not be deleted.\n", keypath);
191 }
192 }
193
iterator_init(btstack_link_key_iterator_t * it)194 static int iterator_init(btstack_link_key_iterator_t * it){
195 tinydir_dir * dir = (tinydir_dir *) malloc(sizeof(tinydir_dir));
196 if (!dir) return 0;
197 it->context = dir;
198 tinydir_open(dir, LINK_KEY_PATH);
199 return 1;
200 }
201
iterator_get_next(btstack_link_key_iterator_t * it,bd_addr_t bd_addr,link_key_t link_key,link_key_type_t * type)202 static int iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
203 (void)bd_addr;
204 (void)link_key;
205 UNUSED(type);
206 tinydir_dir * dir = (tinydir_dir*) it->context;
207
208 // construct prefix
209 strcpy(keypath, LINK_KEY_PREFIX);
210 strcat(keypath, bd_addr_to_dash_str(local_addr));
211 strcat(keypath, LINK_KEY_FOR);
212
213 while (dir->has_next) {
214 tinydir_file file;
215 tinydir_readfile(dir, &file);
216 tinydir_next(dir);
217 // compare
218 if (strncmp(keypath, file.name, strlen(keypath)) == 0){
219 // parse bd_addr
220 const int addr_offset = sizeof(LINK_KEY_PREFIX) + LINK_KEY_STRING_LEN + sizeof(LINK_KEY_FOR) - 2; // -1 for each sizeof
221 sscanf_bd_addr(&file.name[addr_offset], bd_addr);
222 // path found, read file
223 strcpy(keypath, LINK_KEY_PATH);
224 strcat(keypath, file.name);
225 read_link_key(keypath, link_key, type);
226 return 1;
227 }
228 }
229 return 0;
230 }
231
iterator_done(btstack_link_key_iterator_t * it)232 static void iterator_done(btstack_link_key_iterator_t * it){
233 tinydir_close((tinydir_dir*)it->context);
234 free(it->context);
235 it->context = NULL;
236 }
237
238 static const btstack_link_key_db_t btstack_link_key_db_fs = {
239 &db_open,
240 &db_set_local_bd_addr,
241 &db_close,
242 &get_link_key,
243 &put_link_key,
244 &delete_link_key,
245 &iterator_init,
246 &iterator_get_next,
247 &iterator_done,
248 };
249
btstack_link_key_db_fs_instance(void)250 const btstack_link_key_db_t * btstack_link_key_db_fs_instance(void){
251 return &btstack_link_key_db_fs;
252 }
253
254
255