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__ "le_device_db_fs.c"
39
40 #include <stdio.h>
41 #include <string.h>
42
43 #include "btstack_config.h"
44 #include "btstack_debug.h"
45 #include "ble/le_device_db.h"
46 #include "ble/core.h"
47
48 // Central Device db implemenation using static memory
49 typedef struct le_device_memory_db {
50
51 // Identification
52 int addr_type;
53 bd_addr_t addr;
54 sm_key_t irk;
55
56 // Stored pairing information allows to re-establish an enncrypted connection
57 // with a peripheral that doesn't have any persistent memory
58 sm_key_t ltk;
59 uint16_t ediv;
60 uint8_t rand[8];
61 uint8_t key_size;
62 uint8_t authenticated;
63 uint8_t authorized;
64 uint8_t secure_connection;
65
66 #ifdef ENABLE_LE_SIGNED_WRITE
67 // Signed Writes by remote
68 sm_key_t remote_csrk;
69 uint32_t remote_counter;
70
71 // Signed Writes by us
72 sm_key_t local_csrk;
73 uint32_t local_counter;
74 #endif
75
76 } le_device_memory_db_t;
77
78 #define LE_DEVICE_MEMORY_SIZE 20
79
80 #ifndef LE_DEVICE_DB_PATH
81 #ifdef _WIN32
82 #define LE_DEVICE_DB_PATH ""
83 #else
84 #define LE_DEVICE_DB_PATH "/tmp/"
85 #endif
86 #endif
87
88 #define DB_PATH_TEMPLATE (LE_DEVICE_DB_PATH "btstack_at_%s_le_device_db.txt")
89
90 #ifdef ENABLE_LE_SIGNED_WRITE
91 const char * csv_header = "# addr_type, addr, irk, ltk, ediv, rand[8], key_size, authenticated, authorized, remote_csrk, remote_counter, local_csrk, local_counter, secure_connection";
92 #else
93 const char * csv_header = "# addr_type, addr, irk, ltk, ediv, rand[8], key_size, authenticated, authorized, secure_connection";
94 #endif
95
96 static char db_path[sizeof(DB_PATH_TEMPLATE) - 2 + 17 + 1];
97
98 static le_device_memory_db_t le_devices[LE_DEVICE_MEMORY_SIZE];
99
bd_addr_to_dash_str(bd_addr_t addr)100 static char * bd_addr_to_dash_str(bd_addr_t addr){
101 return bd_addr_to_str_with_delimiter(addr, '-');
102 }
103
write_delimiter(FILE * wFile)104 static inline void write_delimiter(FILE * wFile){
105 fwrite(",", 1, 1, wFile);
106 }
write_hex_byte(FILE * wFile,uint8_t value)107 static inline void write_hex_byte(FILE * wFile, uint8_t value){
108 char buffer[2];
109 buffer[0] = char_for_nibble(value >> 4);
110 buffer[1] = char_for_nibble(value & 0x0f);
111 fwrite(buffer, 2, 1, wFile);
112 }
113
write_str(FILE * wFile,const char * str)114 static inline void write_str(FILE * wFile, const char * str){
115 fwrite(str, strlen(str), 1, wFile);
116 write_delimiter(wFile);
117 }
write_hex(FILE * wFile,const uint8_t * value,int len)118 static void write_hex(FILE * wFile, const uint8_t * value, int len){
119 int i;
120 for (i = 0; i < len; i++){
121 write_hex_byte(wFile, value[i]);
122 }
123 write_delimiter(wFile);
124 }
write_value(FILE * wFile,uint32_t value,int len)125 static void write_value(FILE * wFile, uint32_t value, int len){
126 switch (len){
127 case 4:
128 write_hex_byte(wFile, value >> 24);
129 case 3:
130 write_hex_byte(wFile, value >> 16);
131 case 2:
132 write_hex_byte(wFile, value >> 8);
133 case 1:
134 default:
135 write_hex_byte(wFile, value);
136 }
137 write_delimiter(wFile);
138 }
139
le_device_db_store(void)140 static void le_device_db_store(void) {
141 int i;
142 // open file
143 FILE * wFile = fopen(db_path,"w+");
144 if (wFile == NULL) return;
145 fwrite(csv_header, strlen(csv_header), 1, wFile);
146 fwrite("\n", 1, 1, wFile);
147 for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
148 if (le_devices[i].addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
149 write_value(wFile, le_devices[i].addr_type, 1);
150 write_str(wFile, bd_addr_to_str(le_devices[i].addr));
151 write_hex(wFile, le_devices[i].irk, 16);
152 write_hex(wFile, le_devices[i].ltk, 16);
153 write_value(wFile, le_devices[i].ediv, 2);
154 write_hex(wFile, le_devices[i].rand, 8);
155 write_value(wFile, le_devices[i].key_size, 1);
156 write_value(wFile, le_devices[i].authenticated, 1);
157 write_value(wFile, le_devices[i].authorized, 1);
158 #ifdef ENABLE_LE_SIGNED_WRITE
159 write_hex(wFile, le_devices[i].remote_csrk, 16);
160 write_value(wFile, le_devices[i].remote_counter, 2);
161 write_hex(wFile, le_devices[i].local_csrk, 16);
162 write_value(wFile, le_devices[i].local_counter, 2);
163 #endif
164 write_value(wFile, le_devices[i].secure_connection, 1);
165 fwrite("\n", 1, 1, wFile);
166 }
167 fclose(wFile);
168 }
read_delimiter(FILE * wFile)169 static void read_delimiter(FILE * wFile){
170 fgetc(wFile);
171 }
172
read_hex_byte(FILE * wFile)173 static uint8_t read_hex_byte(FILE * wFile){
174 int c = fgetc(wFile);
175 if (c == ':') {
176 c = fgetc(wFile);
177 }
178 int d = fgetc(wFile);
179 return nibble_for_char(c) << 4 | nibble_for_char(d);
180 }
181
read_hex(FILE * wFile,uint8_t * buffer,int len)182 static void read_hex(FILE * wFile, uint8_t * buffer, int len){
183 int i;
184 for (i=0;i<len;i++){
185 buffer[i] = read_hex_byte(wFile);
186 }
187 read_delimiter(wFile);
188 }
189
read_value(FILE * wFile,int len)190 static uint32_t read_value(FILE * wFile, int len){
191 uint32_t res = 0;
192 int i;
193 for (i=0;i<len;i++){
194 res = res << 8 | read_hex_byte(wFile);
195 }
196 read_delimiter(wFile);
197 return res;
198 }
199
le_device_db_read(void)200 static void le_device_db_read(void){
201 // open file
202 FILE * wFile = fopen(db_path,"r");
203 if (wFile == NULL) return;
204 // skip header
205 while (true) {
206 int c = fgetc(wFile);
207 if (feof(wFile)) goto exit;
208 if (c == '\n') break;
209 }
210 // read entries
211 int i;
212 for (i=0 ; i<LE_DEVICE_MEMORY_SIZE ; i++){
213 memset(&le_devices[i], 0, sizeof(le_device_memory_db_t));
214 le_devices[i].addr_type = read_value(wFile, 1);
215 if (feof(wFile)){
216 le_devices[i].addr_type = BD_ADDR_TYPE_UNKNOWN;
217 break;
218 }
219 read_hex(wFile, le_devices[i].addr, 6);
220 read_hex(wFile, le_devices[i].irk, 16);
221 read_hex(wFile, le_devices[i].ltk, 16);
222 le_devices[i].ediv = read_value(wFile, 2);
223 read_hex(wFile, le_devices[i].rand, 8);
224 le_devices[i].key_size = read_value(wFile, 1);
225 le_devices[i].authenticated = read_value(wFile, 1);
226 le_devices[i].authorized = read_value(wFile, 1);
227 #ifdef ENABLE_LE_SIGNED_WRITE
228 read_hex(wFile, le_devices[i].remote_csrk, 16);
229 le_devices[i].remote_counter = read_value(wFile, 2);
230 read_hex(wFile, le_devices[i].local_csrk, 16);
231 le_devices[i].local_counter = read_value(wFile, 2);
232 #endif
233 // read next character and secure connection field if hex nibble follows
234 // (if not, we just read the newline)
235 int c = fgetc(wFile);
236 if (nibble_for_char(c) >= 0){
237 int d = fgetc(wFile);
238 le_devices[i].secure_connection = nibble_for_char(c) << 4 | nibble_for_char(d);
239 // read delimiter
240 read_delimiter(wFile);
241 // read newline
242 fgetc(wFile);
243 }
244 }
245 exit:
246 fclose(wFile);
247 }
248
le_device_db_init(void)249 void le_device_db_init(void){
250 int i;
251 for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
252 le_devices[i].addr_type = BD_ADDR_TYPE_UNKNOWN;
253 }
254 sprintf(db_path, DB_PATH_TEMPLATE, "00-00-00-00-00-00");
255 }
256
le_device_db_set_local_bd_addr(bd_addr_t addr)257 void le_device_db_set_local_bd_addr(bd_addr_t addr){
258 sprintf(db_path, DB_PATH_TEMPLATE, bd_addr_to_dash_str(addr));
259 log_info("le_device_db_fs: path %s", db_path);
260 le_device_db_read();
261 le_device_db_dump();
262 }
263
264 // @returns number of device in db
le_device_db_count(void)265 int le_device_db_count(void){
266 int i;
267 int counter = 0;
268 for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
269 if (le_devices[i].addr_type != BD_ADDR_TYPE_UNKNOWN) counter++;
270 }
271 return counter;
272 }
273
le_device_db_max_count(void)274 int le_device_db_max_count(void){
275 return LE_DEVICE_MEMORY_SIZE;
276 }
277
278 // free device
le_device_db_remove(int index)279 void le_device_db_remove(int index){
280 le_devices[index].addr_type = BD_ADDR_TYPE_UNKNOWN;
281 le_device_db_store();
282 }
283
le_device_db_add(int addr_type,bd_addr_t addr,sm_key_t irk)284 int le_device_db_add(int addr_type, bd_addr_t addr, sm_key_t irk){
285 int i;
286 int index = -1;
287 for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
288 if (le_devices[i].addr_type == BD_ADDR_TYPE_UNKNOWN){
289 index = i;
290 break;
291 }
292 }
293
294 if (index < 0) return -1;
295
296 log_info("Central Device DB adding type %u - %s", addr_type, bd_addr_to_str(addr));
297 log_info_key("irk", irk);
298
299 memset(&le_devices[index], 0, sizeof(le_device_memory_db_t));
300
301 le_devices[index].addr_type = addr_type;
302 memcpy(le_devices[index].addr, addr, 6);
303 memcpy(le_devices[index].irk, irk, 16);
304 #ifdef ENABLE_LE_SIGNED_WRITE
305 le_devices[index].remote_counter = 0;
306 #endif
307 le_device_db_store();
308
309 return index;
310 }
311
312
313 // get device information: addr type and address
le_device_db_info(int index,int * addr_type,bd_addr_t addr,sm_key_t irk)314 void le_device_db_info(int index, int * addr_type, bd_addr_t addr, sm_key_t irk){
315 if (addr_type) *addr_type = le_devices[index].addr_type;
316 if (addr) memcpy(addr, le_devices[index].addr, 6);
317 if (irk) memcpy(irk, le_devices[index].irk, 16);
318 }
319
le_device_db_encryption_set(int index,uint16_t ediv,uint8_t rand[8],sm_key_t ltk,int key_size,int authenticated,int authorized,int secure_connection)320 void le_device_db_encryption_set(int index, uint16_t ediv, uint8_t rand[8], sm_key_t ltk, int key_size, int authenticated, int authorized, int secure_connection){
321 log_info("LE Device DB set encryption for %u, ediv x%04x, key size %u, authenticated %u, authorized %u, secure connection %u",
322 index, ediv, key_size, authenticated, authorized, secure_connection);
323 le_device_memory_db_t * device = &le_devices[index];
324 device->ediv = ediv;
325 if (rand) memcpy(device->rand, rand, 8);
326 if (ltk) memcpy(device->ltk, ltk, 16);
327 device->key_size = key_size;
328 device->authenticated = authenticated;
329 device->authorized = authorized;
330 device->secure_connection = secure_connection;
331
332 le_device_db_store();
333 }
334
le_device_db_encryption_get(int index,uint16_t * ediv,uint8_t rand[8],sm_key_t ltk,int * key_size,int * authenticated,int * authorized,int * secure_connection)335 void le_device_db_encryption_get(int index, uint16_t * ediv, uint8_t rand[8], sm_key_t ltk, int * key_size, int * authenticated, int * authorized, int * secure_connection){
336 le_device_memory_db_t * device = &le_devices[index];
337 log_info("LE Device DB encryption for %u, ediv x%04x, keysize %u, authenticated %u, authorized %u, secure connection %u",
338 index, device->ediv, device->key_size, device->authenticated, device->authorized, device->secure_connection);
339 if (ediv) *ediv = device->ediv;
340 if (rand) memcpy(rand, device->rand, 8);
341 if (ltk) memcpy(ltk, device->ltk, 16);
342 if (key_size) *key_size = device->key_size;
343 if (authenticated) *authenticated = device->authenticated;
344 if (authorized) *authorized = device->authorized;
345 if (secure_connection) *secure_connection = device->secure_connection;
346 }
347
348 #ifdef ENABLE_LE_SIGNED_WRITE
349
350 // get signature key
le_device_db_remote_csrk_get(int index,sm_key_t csrk)351 void le_device_db_remote_csrk_get(int index, sm_key_t csrk){
352 if (index < 0 || index >= LE_DEVICE_MEMORY_SIZE){
353 log_error("le_device_db_remote_csrk_get called with invalid index %d", index);
354 return;
355 }
356 if (csrk) memcpy(csrk, le_devices[index].remote_csrk, 16);
357 }
358
le_device_db_remote_csrk_set(int index,sm_key_t csrk)359 void le_device_db_remote_csrk_set(int index, sm_key_t csrk){
360 if (index < 0 || index >= LE_DEVICE_MEMORY_SIZE){
361 log_error("le_device_db_remote_csrk_set called with invalid index %d", index);
362 return;
363 }
364 if (csrk) memcpy(le_devices[index].remote_csrk, csrk, 16);
365
366 le_device_db_store();
367 }
368
le_device_db_local_csrk_get(int index,sm_key_t csrk)369 void le_device_db_local_csrk_get(int index, sm_key_t csrk){
370 if (index < 0 || index >= LE_DEVICE_MEMORY_SIZE){
371 log_error("le_device_db_local_csrk_get called with invalid index %d", index);
372 return;
373 }
374 if (csrk) memcpy(csrk, le_devices[index].local_csrk, 16);
375 }
376
le_device_db_local_csrk_set(int index,sm_key_t csrk)377 void le_device_db_local_csrk_set(int index, sm_key_t csrk){
378 if (index < 0 || index >= LE_DEVICE_MEMORY_SIZE){
379 log_error("le_device_db_local_csrk_set called with invalid index %d", index);
380 return;
381 }
382 if (csrk) memcpy(le_devices[index].local_csrk, csrk, 16);
383
384 le_device_db_store();
385 }
386
387 // query last used/seen signing counter
le_device_db_remote_counter_get(int index)388 uint32_t le_device_db_remote_counter_get(int index){
389 return le_devices[index].remote_counter;
390 }
391
392 // update signing counter
le_device_db_remote_counter_set(int index,uint32_t counter)393 void le_device_db_remote_counter_set(int index, uint32_t counter){
394 le_devices[index].remote_counter = counter;
395
396 le_device_db_store();
397 }
398
399 // query last used/seen signing counter
le_device_db_local_counter_get(int index)400 uint32_t le_device_db_local_counter_get(int index){
401 return le_devices[index].local_counter;
402 }
403
404 // update signing counter
le_device_db_local_counter_set(int index,uint32_t counter)405 void le_device_db_local_counter_set(int index, uint32_t counter){
406 le_devices[index].local_counter = counter;
407
408 le_device_db_store();
409 }
410 #endif
411
le_device_db_dump(void)412 void le_device_db_dump(void){
413 log_info("Central Device DB dump, devices: %d", le_device_db_count());
414 int i;
415 for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
416 if (le_devices[i].addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
417 log_info("%u: %u %s", i, le_devices[i].addr_type, bd_addr_to_str(le_devices[i].addr));
418 log_info_key("ltk", le_devices[i].ltk);
419 log_info_key("irk", le_devices[i].irk);
420 #ifdef ENABLE_LE_SIGNED_WRITE
421 log_info_key("local csrk", le_devices[i].local_csrk);
422 log_info_key("remote csrk", le_devices[i].remote_csrk);
423 #endif
424 }
425 }
426