btif_config.cc revision b7cfd05e917a4c426d7fa24d6d05ed233421409a 
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 <stdio.h>
26#include <string.h>
27#include <time.h>
28#include <unistd.h>
29#include <string>
30
31#include <mutex>
32
33#include "bt_types.h"
34#include "btcore/include/bdaddr.h"
35#include "btcore/include/module.h"
36#include "btif_api.h"
37#include "btif_common.h"
38#include "btif_config_transcode.h"
39#include "btif_util.h"
40#include "osi/include/alarm.h"
41#include "osi/include/allocator.h"
42#include "osi/include/compat.h"
43#include "osi/include/config.h"
44#include "osi/include/log.h"
45#include "osi/include/osi.h"
46#include "osi/include/properties.h"
47
48#define BT_CONFIG_SOURCE_TAG_NUM 1010001
49
50#define INFO_SECTION "Info"
51#define FILE_TIMESTAMP "TimeCreated"
52#define FILE_SOURCE "FileSource"
53#define TIME_STRING_LENGTH sizeof("YYYY-MM-DD HH:MM:SS")
54static const char* TIME_STRING_FORMAT = "%Y-%m-%d %H:%M:%S";
55
56// TODO(armansito): Find a better way than searching by a hardcoded path.
57#if defined(OS_GENERIC)
58static const char* CONFIG_FILE_PATH = "bt_config.conf";
59static const char* CONFIG_BACKUP_PATH = "bt_config.bak";
60static const char* CONFIG_LEGACY_FILE_PATH = "bt_config.xml";
61#else   // !defined(OS_GENERIC)
62static const char* CONFIG_FILE_PATH = "/data/misc/bluedroid/bt_config.conf";
63static const char* CONFIG_BACKUP_PATH = "/data/misc/bluedroid/bt_config.bak";
64static const char* CONFIG_LEGACY_FILE_PATH =
65    "/data/misc/bluedroid/bt_config.xml";
66#endif  // defined(OS_GENERIC)
67static const period_ms_t CONFIG_SETTLE_PERIOD_MS = 3000;
68
69static void timer_config_save_cb(void* data);
70static void btif_config_write(uint16_t event, char* p_param);
71static bool is_factory_reset(void);
72static void delete_config_files(void);
73static void btif_config_remove_unpaired(config_t* config);
74static void btif_config_remove_restricted(config_t* config);
75static config_t* btif_config_open(const char* filename);
76
77static enum ConfigSource {
78  NOT_LOADED,
79  ORIGINAL,
80  BACKUP,
81  LEGACY,
82  NEW_FILE,
83  RESET
84} btif_config_source = NOT_LOADED;
85
86static int btif_config_devices_loaded = -1;
87static char btif_config_time_created[TIME_STRING_LENGTH];
88
89// TODO(zachoverflow): Move these two functions out, because they are too
90// specific for this file
91// {grumpy-cat/no, monty-python/you-make-me-sad}
92bool btif_get_device_type(const BD_ADDR bd_addr, int* p_device_type) {
93  if (p_device_type == NULL) return false;
94
95  bt_bdaddr_t bda;
96  bdcpy(bda.address, bd_addr);
97
98  bdstr_t bd_addr_str;
99  bdaddr_to_string(&bda, bd_addr_str, sizeof(bd_addr_str));
100
101  if (!btif_config_get_int(bd_addr_str, "DevType", p_device_type)) return false;
102
103  LOG_DEBUG(LOG_TAG, "%s: Device [%s] type %d", __func__, bd_addr_str,
104            *p_device_type);
105  return true;
106}
107
108bool btif_get_address_type(const BD_ADDR bd_addr, int* p_addr_type) {
109  if (p_addr_type == NULL) return false;
110
111  bt_bdaddr_t bda;
112  bdcpy(bda.address, bd_addr);
113
114  bdstr_t bd_addr_str;
115  bdaddr_to_string(&bda, bd_addr_str, sizeof(bd_addr_str));
116
117  if (!btif_config_get_int(bd_addr_str, "AddrType", p_addr_type)) return false;
118
119  LOG_DEBUG(LOG_TAG, "%s: Device [%s] address type %d", __func__, bd_addr_str,
120            *p_addr_type);
121  return true;
122}
123
124static std::mutex config_lock;  // protects operations on |config|.
125static config_t* config;
126static alarm_t* config_timer;
127
128// Module lifecycle functions
129
130static future_t* init(void) {
131  std::unique_lock<std::mutex> lock(config_lock);
132
133  if (is_factory_reset()) delete_config_files();
134
135  std::string file_source;
136
137  config = btif_config_open(CONFIG_FILE_PATH);
138  btif_config_source = ORIGINAL;
139  if (!config) {
140    LOG_WARN(LOG_TAG, "%s unable to load config file: %s; using backup.",
141             __func__, CONFIG_FILE_PATH);
142    config = btif_config_open(CONFIG_BACKUP_PATH);
143    btif_config_source = BACKUP;
144    file_source = "Backup";
145  }
146  if (!config) {
147    LOG_WARN(LOG_TAG,
148             "%s unable to load backup; attempting to transcode legacy file.",
149             __func__);
150    config = btif_config_transcode(CONFIG_LEGACY_FILE_PATH);
151    btif_config_source = LEGACY;
152    file_source = "Legacy";
153  }
154  if (!config) {
155    LOG_ERROR(LOG_TAG,
156              "%s unable to transcode legacy file; creating empty config.",
157              __func__);
158    config = config_new_empty();
159    btif_config_source = NEW_FILE;
160    file_source = "Empty";
161  }
162
163  if (!file_source.empty())
164    config_set_string(config, INFO_SECTION, FILE_SOURCE, file_source.c_str());
165
166  if (!config) {
167    LOG_ERROR(LOG_TAG, "%s unable to allocate a config object.", __func__);
168    goto error;
169  }
170
171  btif_config_remove_unpaired(config);
172
173  // Cleanup temporary pairings if we have left guest mode
174  if (!is_restricted_mode()) btif_config_remove_restricted(config);
175
176  // Read or set config file creation timestamp
177  const char* time_str;
178  time_str = config_get_string(config, INFO_SECTION, FILE_TIMESTAMP, NULL);
179  if (time_str != NULL) {
180    strlcpy(btif_config_time_created, time_str, TIME_STRING_LENGTH);
181  } else {
182    time_t current_time = time(NULL);
183    struct tm* time_created = localtime(&current_time);
184    strftime(btif_config_time_created, TIME_STRING_LENGTH, TIME_STRING_FORMAT,
185             time_created);
186    config_set_string(config, INFO_SECTION, FILE_TIMESTAMP,
187                      btif_config_time_created);
188  }
189
190  // TODO(sharvil): use a non-wake alarm for this once we have
191  // API support for it. There's no need to wake the system to
192  // write back to disk.
193  config_timer = alarm_new("btif.config");
194  if (!config_timer) {
195    LOG_ERROR(LOG_TAG, "%s unable to create alarm.", __func__);
196    goto error;
197  }
198
199  LOG_EVENT_INT(BT_CONFIG_SOURCE_TAG_NUM, btif_config_source);
200
201  return future_new_immediate(FUTURE_SUCCESS);
202
203error:
204  alarm_free(config_timer);
205  config_free(config);
206  config_timer = NULL;
207  config = NULL;
208  btif_config_source = NOT_LOADED;
209  return future_new_immediate(FUTURE_FAIL);
210}
211
212static config_t* btif_config_open(const char* filename) {
213  config_t* config = config_new(filename);
214  if (!config) return NULL;
215
216  if (!config_has_section(config, "Adapter")) {
217    LOG_ERROR(LOG_TAG, "Config is missing adapter section");
218    config_free(config);
219    return NULL;
220  }
221
222  return config;
223}
224
225static future_t* shut_down(void) {
226  btif_config_flush();
227  return future_new_immediate(FUTURE_SUCCESS);
228}
229
230static future_t* clean_up(void) {
231  btif_config_flush();
232
233  alarm_free(config_timer);
234  config_free(config);
235  config_timer = NULL;
236  config = NULL;
237  return future_new_immediate(FUTURE_SUCCESS);
238}
239
240EXPORT_SYMBOL module_t btif_config_module = {.name = BTIF_CONFIG_MODULE,
241                                             .init = init,
242                                             .start_up = NULL,
243                                             .shut_down = shut_down,
244                                             .clean_up = clean_up};
245
246bool btif_config_has_section(const char* section) {
247  assert(config != NULL);
248  assert(section != NULL);
249
250  std::unique_lock<std::mutex> lock(config_lock);
251  return config_has_section(config, section);
252}
253
254bool btif_config_exist(const char* section, const char* key) {
255  assert(config != NULL);
256  assert(section != NULL);
257  assert(key != NULL);
258
259  std::unique_lock<std::mutex> lock(config_lock);
260  return config_has_key(config, section, key);
261}
262
263bool btif_config_get_int(const char* section, const char* key, int* value) {
264  assert(config != NULL);
265  assert(section != NULL);
266  assert(key != NULL);
267  assert(value != NULL);
268
269  std::unique_lock<std::mutex> lock(config_lock);
270  bool ret = config_has_key(config, section, key);
271  if (ret) *value = config_get_int(config, section, key, *value);
272
273  return ret;
274}
275
276bool btif_config_set_int(const char* section, const char* key, int value) {
277  assert(config != NULL);
278  assert(section != NULL);
279  assert(key != NULL);
280
281  std::unique_lock<std::mutex> lock(config_lock);
282  config_set_int(config, section, key, value);
283
284  return true;
285}
286
287bool btif_config_get_str(const char* section, const char* key, char* value,
288                         int* size_bytes) {
289  assert(config != NULL);
290  assert(section != NULL);
291  assert(key != NULL);
292  assert(value != NULL);
293  assert(size_bytes != NULL);
294
295  {
296    std::unique_lock<std::mutex> lock(config_lock);
297    const char* stored_value = config_get_string(config, section, key, NULL);
298    if (!stored_value) return false;
299    strlcpy(value, stored_value, *size_bytes);
300  }
301
302  *size_bytes = strlen(value) + 1;
303  return true;
304}
305
306bool btif_config_set_str(const char* section, const char* key,
307                         const char* value) {
308  assert(config != NULL);
309  assert(section != NULL);
310  assert(key != NULL);
311  assert(value != NULL);
312
313  std::unique_lock<std::mutex> lock(config_lock);
314  config_set_string(config, section, key, value);
315  return true;
316}
317
318bool btif_config_get_bin(const char* section, const char* key, uint8_t* value,
319                         size_t* length) {
320  assert(config != NULL);
321  assert(section != NULL);
322  assert(key != NULL);
323  assert(value != NULL);
324  assert(length != NULL);
325
326  std::unique_lock<std::mutex> lock(config_lock);
327  const char* value_str = config_get_string(config, section, key, NULL);
328
329  if (!value_str) return false;
330
331  size_t value_len = strlen(value_str);
332  if ((value_len % 2) != 0 || *length < (value_len / 2)) return false;
333
334  for (size_t i = 0; i < value_len; ++i)
335    if (!isxdigit(value_str[i])) return false;
336
337  for (*length = 0; *value_str; value_str += 2, *length += 1)
338    sscanf(value_str, "%02hhx", &value[*length]);
339
340  return true;
341}
342
343size_t btif_config_get_bin_length(const char* section, const char* key) {
344  assert(config != NULL);
345  assert(section != NULL);
346  assert(key != NULL);
347
348  std::unique_lock<std::mutex> lock(config_lock);
349  const char* value_str = config_get_string(config, section, key, NULL);
350  if (!value_str) return 0;
351
352  size_t value_len = strlen(value_str);
353  return ((value_len % 2) != 0) ? 0 : (value_len / 2);
354}
355
356bool btif_config_set_bin(const char* section, const char* key,
357                         const uint8_t* value, size_t length) {
358  const char* lookup = "0123456789abcdef";
359
360  assert(config != NULL);
361  assert(section != NULL);
362  assert(key != NULL);
363
364  if (length > 0) assert(value != NULL);
365
366  char* str = (char*)osi_calloc(length * 2 + 1);
367
368  for (size_t i = 0; i < length; ++i) {
369    str[(i * 2) + 0] = lookup[(value[i] >> 4) & 0x0F];
370    str[(i * 2) + 1] = lookup[value[i] & 0x0F];
371  }
372
373  {
374    std::unique_lock<std::mutex> lock(config_lock);
375    config_set_string(config, section, key, str);
376  }
377
378  osi_free(str);
379  return true;
380}
381
382const btif_config_section_iter_t* btif_config_section_begin(void) {
383  assert(config != NULL);
384  return (const btif_config_section_iter_t*)config_section_begin(config);
385}
386
387const btif_config_section_iter_t* btif_config_section_end(void) {
388  assert(config != NULL);
389  return (const btif_config_section_iter_t*)config_section_end(config);
390}
391
392const btif_config_section_iter_t* btif_config_section_next(
393    const btif_config_section_iter_t* section) {
394  assert(config != NULL);
395  assert(section != NULL);
396  return (const btif_config_section_iter_t*)config_section_next(
397      (const config_section_node_t*)section);
398}
399
400const char* btif_config_section_name(
401    const btif_config_section_iter_t* section) {
402  assert(config != NULL);
403  assert(section != NULL);
404  return config_section_name((const config_section_node_t*)section);
405}
406
407bool btif_config_remove(const char* section, const char* key) {
408  assert(config != NULL);
409  assert(section != NULL);
410  assert(key != NULL);
411
412  std::unique_lock<std::mutex> lock(config_lock);
413  return config_remove_key(config, section, key);
414}
415
416void btif_config_save(void) {
417  assert(config != NULL);
418  assert(config_timer != NULL);
419
420  alarm_set(config_timer, CONFIG_SETTLE_PERIOD_MS, timer_config_save_cb, NULL);
421}
422
423void btif_config_flush(void) {
424  assert(config != NULL);
425  assert(config_timer != NULL);
426
427  alarm_cancel(config_timer);
428  btif_config_write(0, NULL);
429}
430
431bool btif_config_clear(void) {
432  assert(config != NULL);
433  assert(config_timer != NULL);
434
435  alarm_cancel(config_timer);
436
437  std::unique_lock<std::mutex> lock(config_lock);
438  config_free(config);
439
440  config = config_new_empty();
441  if (config == NULL) return false;
442
443  bool ret = config_save(config, CONFIG_FILE_PATH);
444  btif_config_source = RESET;
445  return ret;
446}
447
448static void timer_config_save_cb(UNUSED_ATTR void* data) {
449  // Moving file I/O to btif context instead of timer callback because
450  // it usually takes a lot of time to be completed, introducing
451  // delays during A2DP playback causing blips or choppiness.
452  btif_transfer_context(btif_config_write, 0, NULL, 0, NULL);
453}
454
455static void btif_config_write(UNUSED_ATTR uint16_t event,
456                              UNUSED_ATTR char* p_param) {
457  assert(config != NULL);
458  assert(config_timer != NULL);
459
460  std::unique_lock<std::mutex> lock(config_lock);
461  rename(CONFIG_FILE_PATH, CONFIG_BACKUP_PATH);
462  config_t* config_paired = config_new_clone(config);
463  btif_config_remove_unpaired(config_paired);
464  config_save(config_paired, CONFIG_FILE_PATH);
465  config_free(config_paired);
466}
467
468static void btif_config_remove_unpaired(config_t* conf) {
469  assert(conf != NULL);
470  int paired_devices = 0;
471
472  // The paired config used to carry information about
473  // discovered devices during regular inquiry scans.
474  // We remove these now and cache them in memory instead.
475  const config_section_node_t* snode = config_section_begin(conf);
476  while (snode != config_section_end(conf)) {
477    const char* section = config_section_name(snode);
478    if (string_is_bdaddr(section)) {
479      if (!config_has_key(conf, section, "LinkKey") &&
480          !config_has_key(conf, section, "LE_KEY_PENC") &&
481          !config_has_key(conf, section, "LE_KEY_PID") &&
482          !config_has_key(conf, section, "LE_KEY_PCSRK") &&
483          !config_has_key(conf, section, "LE_KEY_LENC") &&
484          !config_has_key(conf, section, "LE_KEY_LCSRK")) {
485        snode = config_section_next(snode);
486        config_remove_section(conf, section);
487        continue;
488      }
489      paired_devices++;
490    }
491    snode = config_section_next(snode);
492  }
493
494  // should only happen once, at initial load time
495  if (btif_config_devices_loaded == -1)
496    btif_config_devices_loaded = paired_devices;
497}
498
499void btif_debug_config_dump(int fd) {
500  dprintf(fd, "\nBluetooth Config:\n");
501
502  dprintf(fd, "  Config Source: ");
503  switch (btif_config_source) {
504    case NOT_LOADED:
505      dprintf(fd, "Not loaded\n");
506      break;
507    case ORIGINAL:
508      dprintf(fd, "Original file\n");
509      break;
510    case BACKUP:
511      dprintf(fd, "Backup file\n");
512      break;
513    case LEGACY:
514      dprintf(fd, "Legacy file\n");
515      break;
516    case NEW_FILE:
517      dprintf(fd, "New file\n");
518      break;
519    case RESET:
520      dprintf(fd, "Reset file\n");
521      break;
522  }
523
524  dprintf(fd, "  Devices loaded: %d\n", btif_config_devices_loaded);
525  dprintf(fd, "  File created/tagged: %s\n", btif_config_time_created);
526  dprintf(fd, "  File source: %s\n",
527          config_get_string(config, INFO_SECTION, FILE_SOURCE, "Original"));
528}
529
530static void btif_config_remove_restricted(config_t* config) {
531  assert(config != NULL);
532
533  const config_section_node_t* snode = config_section_begin(config);
534  while (snode != config_section_end(config)) {
535    const char* section = config_section_name(snode);
536    if (string_is_bdaddr(section) &&
537        config_has_key(config, section, "Restricted")) {
538      BTIF_TRACE_DEBUG("%s: Removing restricted device %s", __func__, section);
539      config_remove_section(config, section);
540    }
541    snode = config_section_next(snode);
542  }
543}
544
545static bool is_factory_reset(void) {
546  char factory_reset[PROPERTY_VALUE_MAX] = {0};
547  osi_property_get("persist.bluetooth.factoryreset", factory_reset, "false");
548  return strncmp(factory_reset, "true", 4) == 0;
549}
550
551static void delete_config_files(void) {
552  remove(CONFIG_FILE_PATH);
553  remove(CONFIG_BACKUP_PATH);
554  osi_property_set("persist.bluetooth.factoryreset", "false");
555}
556