btif_config.cc revision 646134e0a04459f649cb50aa9f3272054630c345 
1/******************************************************************************
2 *
3 *  Copyright (C) 2014 Google, Inc.
4 *
5 *  Licensed under the Apache License, Version 2.0 (the "License");
6 *  you may not use this file except in compliance with the License.
7 *  You may obtain a copy of the License at:
8 *
9 *  http://www.apache.org/licenses/LICENSE-2.0
10 *
11 *  Unless required by applicable law or agreed to in writing, software
12 *  distributed under the License is distributed on an "AS IS" BASIS,
13 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 *  See the License for the specific language governing permissions and
15 *  limitations under the License.
16 *
17 ******************************************************************************/
18
19#define LOG_TAG "bt_btif_config"
20
21#include "btif_config.h"
22
23#include <assert.h>
24#include <ctype.h>
25#include <pthread.h>
26#include <stdio.h>
27#include <string.h>
28#include <time.h>
29#include <unistd.h>
30
31#include "bt_types.h"
32#include "btcore/include/bdaddr.h"
33#include "btcore/include/module.h"
34#include "btif_api.h"
35#include "btif_common.h"
36#include "btif_config.h"
37#include "btif_config_transcode.h"
38#include "btif_util.h"
39#include "osi/include/alarm.h"
40#include "osi/include/allocator.h"
41#include "osi/include/compat.h"
42#include "osi/include/config.h"
43#include "osi/include/log.h"
44#include "osi/include/osi.h"
45#include "osi/include/properties.h"
46
47#define INFO_SECTION "Info"
48#define FILE_TIMESTAMP "TimeCreated"
49#define TIME_STRING_LENGTH sizeof("YYYY-MM-DD HH:MM:SS")
50static const char* TIME_STRING_FORMAT = "%Y-%m-%d %H:%M:%S";
51
52// TODO(armansito): Find a better way than searching by a hardcoded path.
53#if defined(OS_GENERIC)
54static const char *CONFIG_FILE_PATH = "bt_config.conf";
55static const char *CONFIG_BACKUP_PATH = "bt_config.bak";
56static const char *CONFIG_LEGACY_FILE_PATH = "bt_config.xml";
57#else  // !defined(OS_GENERIC)
58static const char *CONFIG_FILE_PATH = "/data/misc/bluedroid/bt_config.conf";
59static const char *CONFIG_BACKUP_PATH = "/data/misc/bluedroid/bt_config.bak";
60static const char *CONFIG_LEGACY_FILE_PATH = "/data/misc/bluedroid/bt_config.xml";
61#endif  // defined(OS_GENERIC)
62static const period_ms_t CONFIG_SETTLE_PERIOD_MS = 3000;
63
64static void timer_config_save_cb(void *data);
65static void btif_config_write(UINT16 event, char *p_param);
66static bool is_factory_reset(void);
67static void delete_config_files(void);
68static void btif_config_remove_unpaired(config_t *config);
69static void btif_config_remove_restricted(config_t *config);
70
71static enum ConfigSource {
72  NOT_LOADED,
73  ORIGINAL,
74  BACKUP,
75  LEGACY,
76  NEW_FILE,
77  RESET
78} btif_config_source = NOT_LOADED;
79
80static int btif_config_devices_loaded = -1;
81static char btif_config_time_created[TIME_STRING_LENGTH];
82
83// TODO(zachoverflow): Move these two functions out, because they are too specific for this file
84// {grumpy-cat/no, monty-python/you-make-me-sad}
85bool btif_get_device_type(const BD_ADDR bd_addr, int *p_device_type)
86{
87    if (p_device_type == NULL)
88        return FALSE;
89
90    bt_bdaddr_t bda;
91    bdcpy(bda.address, bd_addr);
92
93    bdstr_t bd_addr_str;
94    bdaddr_to_string(&bda, bd_addr_str, sizeof(bd_addr_str));
95
96    if (!btif_config_get_int(bd_addr_str, "DevType", p_device_type))
97        return FALSE;
98
99    LOG_DEBUG(LOG_TAG, "%s: Device [%s] type %d", __FUNCTION__, bd_addr_str, *p_device_type);
100    return TRUE;
101}
102
103bool btif_get_address_type(const BD_ADDR bd_addr, int *p_addr_type)
104{
105    if (p_addr_type == NULL)
106        return FALSE;
107
108    bt_bdaddr_t bda;
109    bdcpy(bda.address, bd_addr);
110
111    bdstr_t bd_addr_str;
112    bdaddr_to_string(&bda, bd_addr_str, sizeof(bd_addr_str));
113
114    if (!btif_config_get_int(bd_addr_str, "AddrType", p_addr_type))
115        return FALSE;
116
117    LOG_DEBUG(LOG_TAG, "%s: Device [%s] address type %d", __FUNCTION__, bd_addr_str, *p_addr_type);
118    return TRUE;
119}
120
121static pthread_mutex_t lock;  // protects operations on |config|.
122static config_t *config;
123static alarm_t *config_timer;
124
125// Module lifecycle functions
126
127static future_t *init(void) {
128  pthread_mutex_init(&lock, NULL);
129  pthread_mutex_lock(&lock);
130
131  if (is_factory_reset())
132    delete_config_files();
133
134  config = config_new(CONFIG_FILE_PATH);
135  btif_config_source = ORIGINAL;
136  if (!config) {
137    LOG_WARN(LOG_TAG, "%s unable to load config file: %s; using backup.",
138              __func__, CONFIG_FILE_PATH);
139    config = config_new(CONFIG_BACKUP_PATH);
140    btif_config_source = BACKUP;
141  }
142  if (!config) {
143    LOG_WARN(LOG_TAG, "%s unable to load backup; attempting to transcode legacy file.", __func__);
144    config = btif_config_transcode(CONFIG_LEGACY_FILE_PATH);
145    btif_config_source = LEGACY;
146  }
147  if (!config) {
148    LOG_ERROR(LOG_TAG, "%s unable to transcode legacy file; creating empty config.", __func__);
149    config = config_new_empty();
150    btif_config_source = NEW_FILE;
151  }
152  if (!config) {
153    LOG_ERROR(LOG_TAG, "%s unable to allocate a config object.", __func__);
154    goto error;
155  }
156
157  btif_config_remove_unpaired(config);
158
159  // Cleanup temporary pairings if we have left guest mode
160  if (!is_restricted_mode())
161    btif_config_remove_restricted(config);
162
163  // Read or set config file creation timestamp
164  const char* time_str = config_get_string(config, INFO_SECTION, FILE_TIMESTAMP, NULL);
165  if (time_str != NULL) {
166    strlcpy(btif_config_time_created, time_str, TIME_STRING_LENGTH);
167  } else {
168    time_t current_time = time(NULL);
169    struct tm* time_created = localtime(&current_time);
170    strftime(btif_config_time_created, TIME_STRING_LENGTH, TIME_STRING_FORMAT, time_created);
171    config_set_string(config, INFO_SECTION, FILE_TIMESTAMP, btif_config_time_created);
172  }
173
174  // TODO(sharvil): use a non-wake alarm for this once we have
175  // API support for it. There's no need to wake the system to
176  // write back to disk.
177  config_timer = alarm_new("btif.config");
178  if (!config_timer) {
179    LOG_ERROR(LOG_TAG, "%s unable to create alarm.", __func__);
180    goto error;
181  }
182
183  pthread_mutex_unlock(&lock);
184  return future_new_immediate(FUTURE_SUCCESS);
185
186error:
187  alarm_free(config_timer);
188  config_free(config);
189  pthread_mutex_unlock(&lock);
190  pthread_mutex_destroy(&lock);
191  config_timer = NULL;
192  config = NULL;
193  btif_config_source = NOT_LOADED;
194  return future_new_immediate(FUTURE_FAIL);
195}
196
197static future_t *shut_down(void) {
198  btif_config_flush();
199  return future_new_immediate(FUTURE_SUCCESS);
200}
201
202static future_t *clean_up(void) {
203  btif_config_flush();
204
205  alarm_free(config_timer);
206  config_free(config);
207  pthread_mutex_destroy(&lock);
208  config_timer = NULL;
209  config = NULL;
210  return future_new_immediate(FUTURE_SUCCESS);
211}
212
213EXPORT_SYMBOL const module_t btif_config_module = {
214  .name = BTIF_CONFIG_MODULE,
215  .init = init,
216  .start_up = NULL,
217  .shut_down = shut_down,
218  .clean_up = clean_up,
219  .dependencies = {
220    NULL
221  }
222};
223
224bool btif_config_has_section(const char *section) {
225  assert(config != NULL);
226  assert(section != NULL);
227
228  pthread_mutex_lock(&lock);
229  bool ret = config_has_section(config, section);
230  pthread_mutex_unlock(&lock);
231
232  return ret;
233}
234
235bool btif_config_exist(const char *section, const char *key) {
236  assert(config != NULL);
237  assert(section != NULL);
238  assert(key != NULL);
239
240  pthread_mutex_lock(&lock);
241  bool ret = config_has_key(config, section, key);
242  pthread_mutex_unlock(&lock);
243
244  return ret;
245}
246
247bool btif_config_get_int(const char *section, const char *key, int *value) {
248  assert(config != NULL);
249  assert(section != NULL);
250  assert(key != NULL);
251  assert(value != NULL);
252
253  pthread_mutex_lock(&lock);
254  bool ret = config_has_key(config, section, key);
255  if (ret)
256    *value = config_get_int(config, section, key, *value);
257  pthread_mutex_unlock(&lock);
258
259  return ret;
260}
261
262bool btif_config_set_int(const char *section, const char *key, int value) {
263  assert(config != NULL);
264  assert(section != NULL);
265  assert(key != NULL);
266
267  pthread_mutex_lock(&lock);
268  config_set_int(config, section, key, value);
269  pthread_mutex_unlock(&lock);
270
271  return true;
272}
273
274bool btif_config_get_str(const char *section, const char *key, char *value, int *size_bytes) {
275  assert(config != NULL);
276  assert(section != NULL);
277  assert(key != NULL);
278  assert(value != NULL);
279  assert(size_bytes != NULL);
280
281  pthread_mutex_lock(&lock);
282  const char *stored_value = config_get_string(config, section, key, NULL);
283  pthread_mutex_unlock(&lock);
284
285  if (!stored_value)
286    return false;
287
288  strlcpy(value, stored_value, *size_bytes);
289  *size_bytes = strlen(value) + 1;
290
291  return true;
292}
293
294bool btif_config_set_str(const char *section, const char *key, const char *value) {
295  assert(config != NULL);
296  assert(section != NULL);
297  assert(key != NULL);
298  assert(value != NULL);
299
300  pthread_mutex_lock(&lock);
301  config_set_string(config, section, key, value);
302  pthread_mutex_unlock(&lock);
303
304  return true;
305}
306
307bool btif_config_get_bin(const char *section, const char *key, uint8_t *value, size_t *length) {
308  assert(config != NULL);
309  assert(section != NULL);
310  assert(key != NULL);
311  assert(value != NULL);
312  assert(length != NULL);
313
314  pthread_mutex_lock(&lock);
315  const char *value_str = config_get_string(config, section, key, NULL);
316  pthread_mutex_unlock(&lock);
317
318  if (!value_str)
319    return false;
320
321  size_t value_len = strlen(value_str);
322  if ((value_len % 2) != 0 || *length < (value_len / 2))
323    return false;
324
325  for (size_t i = 0; i < value_len; ++i)
326    if (!isxdigit(value_str[i]))
327      return false;
328
329  for (*length = 0; *value_str; value_str += 2, *length += 1)
330    sscanf(value_str, "%02hhx", &value[*length]);
331
332  return true;
333}
334
335size_t btif_config_get_bin_length(const char *section, const char *key) {
336  assert(config != NULL);
337  assert(section != NULL);
338  assert(key != NULL);
339
340  pthread_mutex_lock(&lock);
341  const char *value_str = config_get_string(config, section, key, NULL);
342  pthread_mutex_unlock(&lock);
343
344  if (!value_str)
345    return 0;
346
347  size_t value_len = strlen(value_str);
348  return ((value_len % 2) != 0) ? 0 : (value_len / 2);
349}
350
351bool btif_config_set_bin(const char *section, const char *key, const uint8_t *value, size_t length) {
352  const char *lookup = "0123456789abcdef";
353
354  assert(config != NULL);
355  assert(section != NULL);
356  assert(key != NULL);
357
358  if (length > 0)
359      assert(value != NULL);
360
361  char *str = (char *)osi_calloc(length * 2 + 1);
362
363  for (size_t i = 0; i < length; ++i) {
364    str[(i * 2) + 0] = lookup[(value[i] >> 4) & 0x0F];
365    str[(i * 2) + 1] = lookup[value[i] & 0x0F];
366  }
367
368  pthread_mutex_lock(&lock);
369  config_set_string(config, section, key, str);
370  pthread_mutex_unlock(&lock);
371
372  osi_free(str);
373  return true;
374}
375
376const btif_config_section_iter_t *btif_config_section_begin(void) {
377  assert(config != NULL);
378  return (const btif_config_section_iter_t *)config_section_begin(config);
379}
380
381const btif_config_section_iter_t *btif_config_section_end(void) {
382  assert(config != NULL);
383  return (const btif_config_section_iter_t *)config_section_end(config);
384}
385
386const btif_config_section_iter_t *btif_config_section_next(const btif_config_section_iter_t *section) {
387  assert(config != NULL);
388  assert(section != NULL);
389  return (const btif_config_section_iter_t *)config_section_next((const config_section_node_t *)section);
390}
391
392const char *btif_config_section_name(const btif_config_section_iter_t *section) {
393  assert(config != NULL);
394  assert(section != NULL);
395  return config_section_name((const config_section_node_t *)section);
396}
397
398bool btif_config_remove(const char *section, const char *key) {
399  assert(config != NULL);
400  assert(section != NULL);
401  assert(key != NULL);
402
403  pthread_mutex_lock(&lock);
404  bool ret = config_remove_key(config, section, key);
405  pthread_mutex_unlock(&lock);
406
407  return ret;
408}
409
410void btif_config_save(void) {
411  assert(config != NULL);
412  assert(config_timer != NULL);
413
414  alarm_set(config_timer, CONFIG_SETTLE_PERIOD_MS, timer_config_save_cb, NULL);
415}
416
417void btif_config_flush(void) {
418  assert(config != NULL);
419  assert(config_timer != NULL);
420
421  alarm_cancel(config_timer);
422  btif_config_write(0, NULL);
423}
424
425bool btif_config_clear(void) {
426  assert(config != NULL);
427  assert(config_timer != NULL);
428
429  alarm_cancel(config_timer);
430
431  pthread_mutex_lock(&lock);
432  config_free(config);
433
434  config = config_new_empty();
435  if (config == NULL) {
436    pthread_mutex_unlock(&lock);
437    return false;
438  }
439
440  bool ret = config_save(config, CONFIG_FILE_PATH);
441  btif_config_source = RESET;
442  pthread_mutex_unlock(&lock);
443  return ret;
444}
445
446static void timer_config_save_cb(UNUSED_ATTR void *data) {
447  // Moving file I/O to btif context instead of timer callback because
448  // it usually takes a lot of time to be completed, introducing
449  // delays during A2DP playback causing blips or choppiness.
450  btif_transfer_context(btif_config_write, 0, NULL, 0, NULL);
451}
452
453static void btif_config_write(UNUSED_ATTR UINT16 event, UNUSED_ATTR char *p_param) {
454  assert(config != NULL);
455  assert(config_timer != NULL);
456
457  pthread_mutex_lock(&lock);
458  rename(CONFIG_FILE_PATH, CONFIG_BACKUP_PATH);
459  sync();
460  config_t *config_paired = config_new_clone(config);
461  btif_config_remove_unpaired(config_paired);
462  config_save(config_paired, CONFIG_FILE_PATH);
463  config_free(config_paired);
464  pthread_mutex_unlock(&lock);
465}
466
467static void btif_config_remove_unpaired(config_t *conf) {
468  assert(conf != NULL);
469  int paired_devices = 0;
470
471  // The paired config used to carry information about
472  // discovered devices during regular inquiry scans.
473  // We remove these now and cache them in memory instead.
474  const config_section_node_t *snode = config_section_begin(conf);
475  while (snode != config_section_end(conf)) {
476    const char *section = config_section_name(snode);
477    if (string_is_bdaddr(section)) {
478      if (!config_has_key(conf, section, "LinkKey") &&
479          !config_has_key(conf, section, "LE_KEY_PENC") &&
480          !config_has_key(conf, section, "LE_KEY_PID") &&
481          !config_has_key(conf, section, "LE_KEY_PCSRK") &&
482          !config_has_key(conf, section, "LE_KEY_LENC") &&
483          !config_has_key(conf, section, "LE_KEY_LCSRK")) {
484        snode = config_section_next(snode);
485        config_remove_section(conf, section);
486        continue;
487      }
488      paired_devices++;
489    }
490    snode = config_section_next(snode);
491  }
492
493  // should only happen once, at initial load time
494  if (btif_config_devices_loaded == -1)
495    btif_config_devices_loaded = paired_devices;
496}
497
498void btif_debug_config_dump(int fd) {
499    dprintf(fd, "\nBluetooth Config:\n");
500
501    dprintf(fd, "  Config Source: ");
502    switch(btif_config_source) {
503        case NOT_LOADED:
504            dprintf(fd, "Not loaded\n");
505            break;
506        case ORIGINAL:
507            dprintf(fd, "Original file\n");
508            break;
509        case BACKUP:
510            dprintf(fd, "Backup file\n");
511            break;
512        case LEGACY:
513            dprintf(fd, "Legacy file\n");
514            break;
515        case NEW_FILE:
516            dprintf(fd, "New file\n");
517            break;
518        case RESET:
519            dprintf(fd, "Reset file\n");
520            break;
521    }
522
523    dprintf(fd, "  Devices loaded: %d\n", btif_config_devices_loaded);
524    dprintf(fd, "  File created/tagged: %s\n", btif_config_time_created);
525}
526
527static void btif_config_remove_restricted(config_t* config) {
528  assert(config != NULL);
529
530  const config_section_node_t *snode = config_section_begin(config);
531  while (snode != config_section_end(config)) {
532    const char *section = config_section_name(snode);
533    if (string_is_bdaddr(section) && config_has_key(config, section, "Restricted")) {
534        BTIF_TRACE_DEBUG("%s: Removing restricted device %s", __func__, section);
535        config_remove_section(config, section);
536    }
537    snode = config_section_next(snode);
538  }
539}
540
541static bool is_factory_reset(void) {
542  char factory_reset[PROPERTY_VALUE_MAX] = {0};
543  osi_property_get("persist.bluetooth.factoryreset", factory_reset, "false");
544  return strncmp(factory_reset, "true", 4) == 0;
545}
546
547static void delete_config_files(void) {
548  remove(CONFIG_FILE_PATH);
549  remove(CONFIG_BACKUP_PATH);
550  osi_property_set("persist.bluetooth.factoryreset", "false");
551}
552