btif_config.cc revision ecadb0d01d305f717e01d03391e3062fbaa2b42e 
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 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_timer = NULL;
235
236  std::unique_lock<std::mutex> lock(config_lock);
237  config_free(config);
238  config = NULL;
239  return future_new_immediate(FUTURE_SUCCESS);
240}
241
242EXPORT_SYMBOL module_t btif_config_module = {.name = BTIF_CONFIG_MODULE,
243                                             .init = init,
244                                             .start_up = NULL,
245                                             .shut_down = shut_down,
246                                             .clean_up = clean_up};
247
248bool btif_config_has_section(const char* section) {
249  CHECK(config != NULL);
250  CHECK(section != NULL);
251
252  std::unique_lock<std::mutex> lock(config_lock);
253  return config_has_section(config, section);
254}
255
256bool btif_config_exist(const char* section, const char* key) {
257  CHECK(config != NULL);
258  CHECK(section != NULL);
259  CHECK(key != NULL);
260
261  std::unique_lock<std::mutex> lock(config_lock);
262  return config_has_key(config, section, key);
263}
264
265bool btif_config_get_int(const char* section, const char* key, int* value) {
266  CHECK(config != NULL);
267  CHECK(section != NULL);
268  CHECK(key != NULL);
269  CHECK(value != NULL);
270
271  std::unique_lock<std::mutex> lock(config_lock);
272  bool ret = config_has_key(config, section, key);
273  if (ret) *value = config_get_int(config, section, key, *value);
274
275  return ret;
276}
277
278bool btif_config_set_int(const char* section, const char* key, int value) {
279  CHECK(config != NULL);
280  CHECK(section != NULL);
281  CHECK(key != NULL);
282
283  std::unique_lock<std::mutex> lock(config_lock);
284  config_set_int(config, section, key, value);
285
286  return true;
287}
288
289bool btif_config_get_str(const char* section, const char* key, char* value,
290                         int* size_bytes) {
291  CHECK(config != NULL);
292  CHECK(section != NULL);
293  CHECK(key != NULL);
294  CHECK(value != NULL);
295  CHECK(size_bytes != NULL);
296
297  {
298    std::unique_lock<std::mutex> lock(config_lock);
299    const char* stored_value = config_get_string(config, section, key, NULL);
300    if (!stored_value) return false;
301    strlcpy(value, stored_value, *size_bytes);
302  }
303
304  *size_bytes = strlen(value) + 1;
305  return true;
306}
307
308bool btif_config_set_str(const char* section, const char* key,
309                         const char* value) {
310  CHECK(config != NULL);
311  CHECK(section != NULL);
312  CHECK(key != NULL);
313  CHECK(value != NULL);
314
315  std::unique_lock<std::mutex> lock(config_lock);
316  config_set_string(config, section, key, value);
317  return true;
318}
319
320bool btif_config_get_bin(const char* section, const char* key, uint8_t* value,
321                         size_t* length) {
322  CHECK(config != NULL);
323  CHECK(section != NULL);
324  CHECK(key != NULL);
325  CHECK(value != NULL);
326  CHECK(length != NULL);
327
328  std::unique_lock<std::mutex> lock(config_lock);
329  const char* value_str = config_get_string(config, section, key, NULL);
330
331  if (!value_str) return false;
332
333  size_t value_len = strlen(value_str);
334  if ((value_len % 2) != 0 || *length < (value_len / 2)) return false;
335
336  for (size_t i = 0; i < value_len; ++i)
337    if (!isxdigit(value_str[i])) return false;
338
339  for (*length = 0; *value_str; value_str += 2, *length += 1)
340    sscanf(value_str, "%02hhx", &value[*length]);
341
342  return true;
343}
344
345size_t btif_config_get_bin_length(const char* section, const char* key) {
346  CHECK(config != NULL);
347  CHECK(section != NULL);
348  CHECK(key != NULL);
349
350  std::unique_lock<std::mutex> lock(config_lock);
351  const char* value_str = config_get_string(config, section, key, NULL);
352  if (!value_str) return 0;
353
354  size_t value_len = strlen(value_str);
355  return ((value_len % 2) != 0) ? 0 : (value_len / 2);
356}
357
358bool btif_config_set_bin(const char* section, const char* key,
359                         const uint8_t* value, size_t length) {
360  const char* lookup = "0123456789abcdef";
361
362  CHECK(config != NULL);
363  CHECK(section != NULL);
364  CHECK(key != NULL);
365
366  if (length > 0) CHECK(value != NULL);
367
368  char* str = (char*)osi_calloc(length * 2 + 1);
369
370  for (size_t i = 0; i < length; ++i) {
371    str[(i * 2) + 0] = lookup[(value[i] >> 4) & 0x0F];
372    str[(i * 2) + 1] = lookup[value[i] & 0x0F];
373  }
374
375  {
376    std::unique_lock<std::mutex> lock(config_lock);
377    config_set_string(config, section, key, str);
378  }
379
380  osi_free(str);
381  return true;
382}
383
384const btif_config_section_iter_t* btif_config_section_begin(void) {
385  CHECK(config != NULL);
386  return (const btif_config_section_iter_t*)config_section_begin(config);
387}
388
389const btif_config_section_iter_t* btif_config_section_end(void) {
390  CHECK(config != NULL);
391  return (const btif_config_section_iter_t*)config_section_end(config);
392}
393
394const btif_config_section_iter_t* btif_config_section_next(
395    const btif_config_section_iter_t* section) {
396  CHECK(config != NULL);
397  CHECK(section != NULL);
398  return (const btif_config_section_iter_t*)config_section_next(
399      (const config_section_node_t*)section);
400}
401
402const char* btif_config_section_name(
403    const btif_config_section_iter_t* section) {
404  CHECK(config != NULL);
405  CHECK(section != NULL);
406  return config_section_name((const config_section_node_t*)section);
407}
408
409bool btif_config_remove(const char* section, const char* key) {
410  CHECK(config != NULL);
411  CHECK(section != NULL);
412  CHECK(key != NULL);
413
414  std::unique_lock<std::mutex> lock(config_lock);
415  return config_remove_key(config, section, key);
416}
417
418void btif_config_save(void) {
419  CHECK(config != NULL);
420  CHECK(config_timer != NULL);
421
422  alarm_set(config_timer, CONFIG_SETTLE_PERIOD_MS, timer_config_save_cb, NULL);
423}
424
425void btif_config_flush(void) {
426  CHECK(config != NULL);
427  CHECK(config_timer != NULL);
428
429  alarm_cancel(config_timer);
430  btif_config_write(0, NULL);
431}
432
433bool btif_config_clear(void) {
434  CHECK(config != NULL);
435  CHECK(config_timer != NULL);
436
437  alarm_cancel(config_timer);
438
439  std::unique_lock<std::mutex> lock(config_lock);
440  config_free(config);
441
442  config = config_new_empty();
443  if (config == NULL) return false;
444
445  bool ret = config_save(config, CONFIG_FILE_PATH);
446  btif_config_source = RESET;
447  return ret;
448}
449
450static void timer_config_save_cb(UNUSED_ATTR void* data) {
451  // Moving file I/O to btif context instead of timer callback because
452  // it usually takes a lot of time to be completed, introducing
453  // delays during A2DP playback causing blips or choppiness.
454  btif_transfer_context(btif_config_write, 0, NULL, 0, NULL);
455}
456
457static void btif_config_write(UNUSED_ATTR uint16_t event,
458                              UNUSED_ATTR char* p_param) {
459  CHECK(config != NULL);
460  CHECK(config_timer != NULL);
461
462  std::unique_lock<std::mutex> lock(config_lock);
463  rename(CONFIG_FILE_PATH, CONFIG_BACKUP_PATH);
464  config_t* config_paired = config_new_clone(config);
465  btif_config_remove_unpaired(config_paired);
466  config_save(config_paired, CONFIG_FILE_PATH);
467  config_free(config_paired);
468}
469
470static void btif_config_remove_unpaired(config_t* conf) {
471  CHECK(conf != NULL);
472  int paired_devices = 0;
473
474  // The paired config used to carry information about
475  // discovered devices during regular inquiry scans.
476  // We remove these now and cache them in memory instead.
477  const config_section_node_t* snode = config_section_begin(conf);
478  while (snode != config_section_end(conf)) {
479    const char* section = config_section_name(snode);
480    if (string_is_bdaddr(section)) {
481      if (!config_has_key(conf, section, "LinkKey") &&
482          !config_has_key(conf, section, "LE_KEY_PENC") &&
483          !config_has_key(conf, section, "LE_KEY_PID") &&
484          !config_has_key(conf, section, "LE_KEY_PCSRK") &&
485          !config_has_key(conf, section, "LE_KEY_LENC") &&
486          !config_has_key(conf, section, "LE_KEY_LCSRK")) {
487        snode = config_section_next(snode);
488        config_remove_section(conf, section);
489        continue;
490      }
491      paired_devices++;
492    }
493    snode = config_section_next(snode);
494  }
495
496  // should only happen once, at initial load time
497  if (btif_config_devices_loaded == -1)
498    btif_config_devices_loaded = paired_devices;
499}
500
501void btif_debug_config_dump(int fd) {
502  dprintf(fd, "\nBluetooth Config:\n");
503
504  dprintf(fd, "  Config Source: ");
505  switch (btif_config_source) {
506    case NOT_LOADED:
507      dprintf(fd, "Not loaded\n");
508      break;
509    case ORIGINAL:
510      dprintf(fd, "Original file\n");
511      break;
512    case BACKUP:
513      dprintf(fd, "Backup file\n");
514      break;
515    case LEGACY:
516      dprintf(fd, "Legacy file\n");
517      break;
518    case NEW_FILE:
519      dprintf(fd, "New file\n");
520      break;
521    case RESET:
522      dprintf(fd, "Reset file\n");
523      break;
524  }
525
526  dprintf(fd, "  Devices loaded: %d\n", btif_config_devices_loaded);
527  dprintf(fd, "  File created/tagged: %s\n", btif_config_time_created);
528  dprintf(fd, "  File source: %s\n",
529          config_get_string(config, INFO_SECTION, FILE_SOURCE, "Original"));
530}
531
532static void btif_config_remove_restricted(config_t* config) {
533  CHECK(config != NULL);
534
535  const config_section_node_t* snode = config_section_begin(config);
536  while (snode != config_section_end(config)) {
537    const char* section = config_section_name(snode);
538    if (string_is_bdaddr(section) &&
539        config_has_key(config, section, "Restricted")) {
540      BTIF_TRACE_DEBUG("%s: Removing restricted device %s", __func__, section);
541      config_remove_section(config, section);
542    }
543    snode = config_section_next(snode);
544  }
545}
546
547static bool is_factory_reset(void) {
548  char factory_reset[PROPERTY_VALUE_MAX] = {0};
549  osi_property_get("persist.bluetooth.factoryreset", factory_reset, "false");
550  return strncmp(factory_reset, "true", 4) == 0;
551}
552
553static void delete_config_files(void) {
554  remove(CONFIG_FILE_PATH);
555  remove(CONFIG_BACKUP_PATH);
556  osi_property_set("persist.bluetooth.factoryreset", "false");
557}
558