btif_config.cc revision c2276b06572ab6fc1f900fbb1f41087e77d47e2a 
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 <base/logging.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 bt_bdaddr_t& bda, int* p_device_type) {
93  if (p_device_type == NULL) return false;
94
95  bdstr_t bd_addr_str;
96  bdaddr_to_string(&bda, bd_addr_str, sizeof(bd_addr_str));
97
98  if (!btif_config_get_int(bd_addr_str, "DevType", p_device_type)) return false;
99
100  LOG_DEBUG(LOG_TAG, "%s: Device [%s] type %d", __func__, bd_addr_str,
101            *p_device_type);
102  return true;
103}
104
105bool btif_get_address_type(const bt_bdaddr_t& bda, int* p_addr_type) {
106  if (p_addr_type == NULL) return false;
107
108  bdstr_t bd_addr_str;
109  bdaddr_to_string(&bda, bd_addr_str, sizeof(bd_addr_str));
110
111  if (!btif_config_get_int(bd_addr_str, "AddrType", p_addr_type)) return false;
112
113  LOG_DEBUG(LOG_TAG, "%s: Device [%s] address type %d", __func__, bd_addr_str,
114            *p_addr_type);
115  return true;
116}
117
118static std::mutex config_lock;  // protects operations on |config|.
119static config_t* config;
120static alarm_t* config_timer;
121
122// Module lifecycle functions
123
124static future_t* init(void) {
125  std::unique_lock<std::mutex> lock(config_lock);
126
127  if (is_factory_reset()) delete_config_files();
128
129  std::string file_source;
130
131  config = btif_config_open(CONFIG_FILE_PATH);
132  btif_config_source = ORIGINAL;
133  if (!config) {
134    LOG_WARN(LOG_TAG, "%s unable to load config file: %s; using backup.",
135             __func__, CONFIG_FILE_PATH);
136    config = btif_config_open(CONFIG_BACKUP_PATH);
137    btif_config_source = BACKUP;
138    file_source = "Backup";
139  }
140  if (!config) {
141    LOG_WARN(LOG_TAG,
142             "%s unable to load backup; attempting to transcode legacy file.",
143             __func__);
144    config = btif_config_transcode(CONFIG_LEGACY_FILE_PATH);
145    btif_config_source = LEGACY;
146    file_source = "Legacy";
147  }
148  if (!config) {
149    LOG_ERROR(LOG_TAG,
150              "%s unable to transcode legacy file; creating empty config.",
151              __func__);
152    config = config_new_empty();
153    btif_config_source = NEW_FILE;
154    file_source = "Empty";
155  }
156
157  if (!file_source.empty())
158    config_set_string(config, INFO_SECTION, FILE_SOURCE, file_source.c_str());
159
160  if (!config) {
161    LOG_ERROR(LOG_TAG, "%s unable to allocate a config object.", __func__);
162    goto error;
163  }
164
165  btif_config_remove_unpaired(config);
166
167  // Cleanup temporary pairings if we have left guest mode
168  if (!is_restricted_mode()) btif_config_remove_restricted(config);
169
170  // Read or set config file creation timestamp
171  const char* time_str;
172  time_str = config_get_string(config, INFO_SECTION, FILE_TIMESTAMP, NULL);
173  if (time_str != NULL) {
174    strlcpy(btif_config_time_created, time_str, TIME_STRING_LENGTH);
175  } else {
176    time_t current_time = time(NULL);
177    struct tm* time_created = localtime(&current_time);
178    strftime(btif_config_time_created, TIME_STRING_LENGTH, TIME_STRING_FORMAT,
179             time_created);
180    config_set_string(config, INFO_SECTION, FILE_TIMESTAMP,
181                      btif_config_time_created);
182  }
183
184  // TODO(sharvil): use a non-wake alarm for this once we have
185  // API support for it. There's no need to wake the system to
186  // write back to disk.
187  config_timer = alarm_new("btif.config");
188  if (!config_timer) {
189    LOG_ERROR(LOG_TAG, "%s unable to create alarm.", __func__);
190    goto error;
191  }
192
193  LOG_EVENT_INT(BT_CONFIG_SOURCE_TAG_NUM, btif_config_source);
194
195  return future_new_immediate(FUTURE_SUCCESS);
196
197error:
198  alarm_free(config_timer);
199  config_free(config);
200  config_timer = NULL;
201  config = NULL;
202  btif_config_source = NOT_LOADED;
203  return future_new_immediate(FUTURE_FAIL);
204}
205
206static config_t* btif_config_open(const char* filename) {
207  config_t* config = config_new(filename);
208  if (!config) return NULL;
209
210  if (!config_has_section(config, "Adapter")) {
211    LOG_ERROR(LOG_TAG, "Config is missing adapter section");
212    config_free(config);
213    return NULL;
214  }
215
216  return config;
217}
218
219static future_t* shut_down(void) {
220  btif_config_flush();
221  return future_new_immediate(FUTURE_SUCCESS);
222}
223
224static future_t* clean_up(void) {
225  btif_config_flush();
226
227  alarm_free(config_timer);
228  config_free(config);
229  config_timer = NULL;
230  config = NULL;
231  return future_new_immediate(FUTURE_SUCCESS);
232}
233
234EXPORT_SYMBOL module_t btif_config_module = {.name = BTIF_CONFIG_MODULE,
235                                             .init = init,
236                                             .start_up = NULL,
237                                             .shut_down = shut_down,
238                                             .clean_up = clean_up};
239
240bool btif_config_has_section(const char* section) {
241  CHECK(config != NULL);
242  CHECK(section != NULL);
243
244  std::unique_lock<std::mutex> lock(config_lock);
245  return config_has_section(config, section);
246}
247
248bool btif_config_exist(const char* section, const char* key) {
249  CHECK(config != NULL);
250  CHECK(section != NULL);
251  CHECK(key != NULL);
252
253  std::unique_lock<std::mutex> lock(config_lock);
254  return config_has_key(config, section, key);
255}
256
257bool btif_config_get_int(const char* section, const char* key, int* value) {
258  CHECK(config != NULL);
259  CHECK(section != NULL);
260  CHECK(key != NULL);
261  CHECK(value != NULL);
262
263  std::unique_lock<std::mutex> lock(config_lock);
264  bool ret = config_has_key(config, section, key);
265  if (ret) *value = config_get_int(config, section, key, *value);
266
267  return ret;
268}
269
270bool btif_config_set_int(const char* section, const char* key, int value) {
271  CHECK(config != NULL);
272  CHECK(section != NULL);
273  CHECK(key != NULL);
274
275  std::unique_lock<std::mutex> lock(config_lock);
276  config_set_int(config, section, key, value);
277
278  return true;
279}
280
281bool btif_config_get_str(const char* section, const char* key, char* value,
282                         int* size_bytes) {
283  CHECK(config != NULL);
284  CHECK(section != NULL);
285  CHECK(key != NULL);
286  CHECK(value != NULL);
287  CHECK(size_bytes != NULL);
288
289  {
290    std::unique_lock<std::mutex> lock(config_lock);
291    const char* stored_value = config_get_string(config, section, key, NULL);
292    if (!stored_value) return false;
293    strlcpy(value, stored_value, *size_bytes);
294  }
295
296  *size_bytes = strlen(value) + 1;
297  return true;
298}
299
300bool btif_config_set_str(const char* section, const char* key,
301                         const char* value) {
302  CHECK(config != NULL);
303  CHECK(section != NULL);
304  CHECK(key != NULL);
305  CHECK(value != NULL);
306
307  std::unique_lock<std::mutex> lock(config_lock);
308  config_set_string(config, section, key, value);
309  return true;
310}
311
312bool btif_config_get_bin(const char* section, const char* key, uint8_t* value,
313                         size_t* length) {
314  CHECK(config != NULL);
315  CHECK(section != NULL);
316  CHECK(key != NULL);
317  CHECK(value != NULL);
318  CHECK(length != NULL);
319
320  std::unique_lock<std::mutex> lock(config_lock);
321  const char* value_str = config_get_string(config, section, key, NULL);
322
323  if (!value_str) return false;
324
325  size_t value_len = strlen(value_str);
326  if ((value_len % 2) != 0 || *length < (value_len / 2)) return false;
327
328  for (size_t i = 0; i < value_len; ++i)
329    if (!isxdigit(value_str[i])) return false;
330
331  for (*length = 0; *value_str; value_str += 2, *length += 1)
332    sscanf(value_str, "%02hhx", &value[*length]);
333
334  return true;
335}
336
337size_t btif_config_get_bin_length(const char* section, const char* key) {
338  CHECK(config != NULL);
339  CHECK(section != NULL);
340  CHECK(key != NULL);
341
342  std::unique_lock<std::mutex> lock(config_lock);
343  const char* value_str = config_get_string(config, section, key, NULL);
344  if (!value_str) return 0;
345
346  size_t value_len = strlen(value_str);
347  return ((value_len % 2) != 0) ? 0 : (value_len / 2);
348}
349
350bool btif_config_set_bin(const char* section, const char* key,
351                         const uint8_t* value, size_t length) {
352  const char* lookup = "0123456789abcdef";
353
354  CHECK(config != NULL);
355  CHECK(section != NULL);
356  CHECK(key != NULL);
357
358  if (length > 0) CHECK(value != NULL);
359
360  char* str = (char*)osi_calloc(length * 2 + 1);
361
362  for (size_t i = 0; i < length; ++i) {
363    str[(i * 2) + 0] = lookup[(value[i] >> 4) & 0x0F];
364    str[(i * 2) + 1] = lookup[value[i] & 0x0F];
365  }
366
367  {
368    std::unique_lock<std::mutex> lock(config_lock);
369    config_set_string(config, section, key, str);
370  }
371
372  osi_free(str);
373  return true;
374}
375
376const btif_config_section_iter_t* btif_config_section_begin(void) {
377  CHECK(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  CHECK(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(
387    const btif_config_section_iter_t* section) {
388  CHECK(config != NULL);
389  CHECK(section != NULL);
390  return (const btif_config_section_iter_t*)config_section_next(
391      (const config_section_node_t*)section);
392}
393
394const char* btif_config_section_name(
395    const btif_config_section_iter_t* section) {
396  CHECK(config != NULL);
397  CHECK(section != NULL);
398  return config_section_name((const config_section_node_t*)section);
399}
400
401bool btif_config_remove(const char* section, const char* key) {
402  CHECK(config != NULL);
403  CHECK(section != NULL);
404  CHECK(key != NULL);
405
406  std::unique_lock<std::mutex> lock(config_lock);
407  return config_remove_key(config, section, key);
408}
409
410void btif_config_save(void) {
411  CHECK(config != NULL);
412  CHECK(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  CHECK(config != NULL);
419  CHECK(config_timer != NULL);
420
421  alarm_cancel(config_timer);
422  btif_config_write(0, NULL);
423}
424
425bool btif_config_clear(void) {
426  CHECK(config != NULL);
427  CHECK(config_timer != NULL);
428
429  alarm_cancel(config_timer);
430
431  std::unique_lock<std::mutex> lock(config_lock);
432  config_free(config);
433
434  config = config_new_empty();
435  if (config == NULL) return false;
436
437  bool ret = config_save(config, CONFIG_FILE_PATH);
438  btif_config_source = RESET;
439  return ret;
440}
441
442static void timer_config_save_cb(UNUSED_ATTR void* data) {
443  // Moving file I/O to btif context instead of timer callback because
444  // it usually takes a lot of time to be completed, introducing
445  // delays during A2DP playback causing blips or choppiness.
446  btif_transfer_context(btif_config_write, 0, NULL, 0, NULL);
447}
448
449static void btif_config_write(UNUSED_ATTR uint16_t event,
450                              UNUSED_ATTR char* p_param) {
451  CHECK(config != NULL);
452  CHECK(config_timer != NULL);
453
454  std::unique_lock<std::mutex> lock(config_lock);
455  rename(CONFIG_FILE_PATH, CONFIG_BACKUP_PATH);
456  config_t* config_paired = config_new_clone(config);
457  btif_config_remove_unpaired(config_paired);
458  config_save(config_paired, CONFIG_FILE_PATH);
459  config_free(config_paired);
460}
461
462static void btif_config_remove_unpaired(config_t* conf) {
463  CHECK(conf != NULL);
464  int paired_devices = 0;
465
466  // The paired config used to carry information about
467  // discovered devices during regular inquiry scans.
468  // We remove these now and cache them in memory instead.
469  const config_section_node_t* snode = config_section_begin(conf);
470  while (snode != config_section_end(conf)) {
471    const char* section = config_section_name(snode);
472    if (string_is_bdaddr(section)) {
473      if (!config_has_key(conf, section, "LinkKey") &&
474          !config_has_key(conf, section, "LE_KEY_PENC") &&
475          !config_has_key(conf, section, "LE_KEY_PID") &&
476          !config_has_key(conf, section, "LE_KEY_PCSRK") &&
477          !config_has_key(conf, section, "LE_KEY_LENC") &&
478          !config_has_key(conf, section, "LE_KEY_LCSRK")) {
479        snode = config_section_next(snode);
480        config_remove_section(conf, section);
481        continue;
482      }
483      paired_devices++;
484    }
485    snode = config_section_next(snode);
486  }
487
488  // should only happen once, at initial load time
489  if (btif_config_devices_loaded == -1)
490    btif_config_devices_loaded = paired_devices;
491}
492
493void btif_debug_config_dump(int fd) {
494  dprintf(fd, "\nBluetooth Config:\n");
495
496  dprintf(fd, "  Config Source: ");
497  switch (btif_config_source) {
498    case NOT_LOADED:
499      dprintf(fd, "Not loaded\n");
500      break;
501    case ORIGINAL:
502      dprintf(fd, "Original file\n");
503      break;
504    case BACKUP:
505      dprintf(fd, "Backup file\n");
506      break;
507    case LEGACY:
508      dprintf(fd, "Legacy file\n");
509      break;
510    case NEW_FILE:
511      dprintf(fd, "New file\n");
512      break;
513    case RESET:
514      dprintf(fd, "Reset file\n");
515      break;
516  }
517
518  dprintf(fd, "  Devices loaded: %d\n", btif_config_devices_loaded);
519  dprintf(fd, "  File created/tagged: %s\n", btif_config_time_created);
520  dprintf(fd, "  File source: %s\n",
521          config_get_string(config, INFO_SECTION, FILE_SOURCE, "Original"));
522}
523
524static void btif_config_remove_restricted(config_t* config) {
525  CHECK(config != NULL);
526
527  const config_section_node_t* snode = config_section_begin(config);
528  while (snode != config_section_end(config)) {
529    const char* section = config_section_name(snode);
530    if (string_is_bdaddr(section) &&
531        config_has_key(config, section, "Restricted")) {
532      BTIF_TRACE_DEBUG("%s: Removing restricted device %s", __func__, section);
533      config_remove_section(config, section);
534    }
535    snode = config_section_next(snode);
536  }
537}
538
539static bool is_factory_reset(void) {
540  char factory_reset[PROPERTY_VALUE_MAX] = {0};
541  osi_property_get("persist.bluetooth.factoryreset", factory_reset, "false");
542  return strncmp(factory_reset, "true", 4) == 0;
543}
544
545static void delete_config_files(void) {
546  remove(CONFIG_FILE_PATH);
547  remove(CONFIG_BACKUP_PATH);
548  osi_property_set("persist.bluetooth.factoryreset", "false");
549}
550