btif_config.cc revision a5764686f719d8d779d8a5ff8cc64010b7893e36 
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>
27#include <string.h>
28#include <time.h>
29#include <unistd.h>
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.h"
39#include "btif_config_transcode.h"
40#include "btif_util.h"
41#include "osi/include/alarm.h"
42#include "osi/include/allocator.h"
43#include "osi/include/compat.h"
44#include "osi/include/config.h"
45#include "osi/include/log.h"
46#include "osi/include/osi.h"
47#include "osi/include/properties.h"
48
49#define BT_CONFIG_SOURCE_TAG_NUM 1010001
50
51#define INFO_SECTION "Info"
52#define FILE_TIMESTAMP "TimeCreated"
53#define FILE_SOURCE "FileSource"
54#define TIME_STRING_LENGTH sizeof("YYYY-MM-DD HH:MM:SS")
55static const char* TIME_STRING_FORMAT = "%Y-%m-%d %H:%M:%S";
56
57// TODO(armansito): Find a better way than searching by a hardcoded path.
58#if defined(OS_GENERIC)
59static const char *CONFIG_FILE_PATH = "bt_config.conf";
60static const char *CONFIG_BACKUP_PATH = "bt_config.bak";
61static const char *CONFIG_LEGACY_FILE_PATH = "bt_config.xml";
62#else  // !defined(OS_GENERIC)
63static const char *CONFIG_FILE_PATH = "/data/misc/bluedroid/bt_config.conf";
64static const char *CONFIG_BACKUP_PATH = "/data/misc/bluedroid/bt_config.bak";
65static const char *CONFIG_LEGACY_FILE_PATH = "/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 specific for this file
90// {grumpy-cat/no, monty-python/you-make-me-sad}
91bool btif_get_device_type(const BD_ADDR bd_addr, int *p_device_type)
92{
93    if (p_device_type == NULL)
94        return false;
95
96    bt_bdaddr_t bda;
97    bdcpy(bda.address, bd_addr);
98
99    bdstr_t bd_addr_str;
100    bdaddr_to_string(&bda, bd_addr_str, sizeof(bd_addr_str));
101
102    if (!btif_config_get_int(bd_addr_str, "DevType", p_device_type))
103        return false;
104
105    LOG_DEBUG(LOG_TAG, "%s: Device [%s] type %d", __func__, bd_addr_str, *p_device_type);
106    return true;
107}
108
109bool btif_get_address_type(const BD_ADDR bd_addr, int *p_addr_type)
110{
111    if (p_addr_type == NULL)
112        return false;
113
114    bt_bdaddr_t bda;
115    bdcpy(bda.address, bd_addr);
116
117    bdstr_t bd_addr_str;
118    bdaddr_to_string(&bda, bd_addr_str, sizeof(bd_addr_str));
119
120    if (!btif_config_get_int(bd_addr_str, "AddrType", p_addr_type))
121        return false;
122
123    LOG_DEBUG(LOG_TAG, "%s: Device [%s] address type %d", __func__, bd_addr_str, *p_addr_type);
124    return true;
125}
126
127static std::mutex config_lock;  // protects operations on |config|.
128static config_t *config;
129static alarm_t *config_timer;
130
131// Module lifecycle functions
132
133static future_t *init(void) {
134  std::unique_lock<std::mutex> lock(config_lock);
135
136  if (is_factory_reset())
137    delete_config_files();
138
139  std::string file_source;
140
141  config = btif_config_open(CONFIG_FILE_PATH);
142  btif_config_source = ORIGINAL;
143  if (!config) {
144    LOG_WARN(LOG_TAG, "%s unable to load config file: %s; using backup.",
145              __func__, CONFIG_FILE_PATH);
146    config = btif_config_open(CONFIG_BACKUP_PATH);
147    btif_config_source = BACKUP;
148    file_source = "Backup";
149  }
150  if (!config) {
151    LOG_WARN(LOG_TAG, "%s unable to load backup; attempting to transcode legacy file.", __func__);
152    config = btif_config_transcode(CONFIG_LEGACY_FILE_PATH);
153    btif_config_source = LEGACY;
154    file_source = "Legacy";
155  }
156  if (!config) {
157    LOG_ERROR(LOG_TAG, "%s unable to transcode legacy file; creating empty config.", __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())
175    btif_config_remove_restricted(config);
176
177  // Read or set config file creation timestamp
178  const char* time_str;
179  time_str = config_get_string(config, INFO_SECTION, FILE_TIMESTAMP, NULL);
180  if (time_str != NULL) {
181    strlcpy(btif_config_time_created, time_str, TIME_STRING_LENGTH);
182  } else {
183    time_t current_time = time(NULL);
184    struct tm* time_created = localtime(&current_time);
185    strftime(btif_config_time_created, TIME_STRING_LENGTH, TIME_STRING_FORMAT, time_created);
186    config_set_string(config, INFO_SECTION, FILE_TIMESTAMP, btif_config_time_created);
187  }
188
189  // TODO(sharvil): use a non-wake alarm for this once we have
190  // API support for it. There's no need to wake the system to
191  // write back to disk.
192  config_timer = alarm_new("btif.config");
193  if (!config_timer) {
194    LOG_ERROR(LOG_TAG, "%s unable to create alarm.", __func__);
195    goto error;
196  }
197
198  LOG_EVENT_INT(BT_CONFIG_SOURCE_TAG_NUM, btif_config_source);
199
200  return future_new_immediate(FUTURE_SUCCESS);
201
202error:
203  alarm_free(config_timer);
204  config_free(config);
205  config_timer = NULL;
206  config = NULL;
207  btif_config_source = NOT_LOADED;
208  return future_new_immediate(FUTURE_FAIL);
209}
210
211static config_t *btif_config_open(const char *filename) {
212  config_t *config = config_new(filename);
213  if (!config)
214    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 = {
241  .name = BTIF_CONFIG_MODULE,
242  .init = init,
243  .start_up = NULL,
244  .shut_down = shut_down,
245  .clean_up = clean_up
246};
247
248bool btif_config_has_section(const char *section) {
249  assert(config != NULL);
250  assert(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  assert(config != NULL);
258  assert(section != NULL);
259  assert(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  assert(config != NULL);
267  assert(section != NULL);
268  assert(key != NULL);
269  assert(value != NULL);
270
271  std::unique_lock<std::mutex> lock(config_lock);
272  bool ret = config_has_key(config, section, key);
273  if (ret)
274    *value = config_get_int(config, section, key, *value);
275
276  return ret;
277}
278
279bool btif_config_set_int(const char *section, const char *key, int value) {
280  assert(config != NULL);
281  assert(section != NULL);
282  assert(key != NULL);
283
284  std::unique_lock<std::mutex> lock(config_lock);
285  config_set_int(config, section, key, value);
286
287  return true;
288}
289
290bool btif_config_get_str(const char *section, const char *key, char *value, int *size_bytes) {
291  assert(config != NULL);
292  assert(section != NULL);
293  assert(key != NULL);
294  assert(value != NULL);
295  assert(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)
301      return false;
302    strlcpy(value, stored_value, *size_bytes);
303  }
304
305  *size_bytes = strlen(value) + 1;
306  return true;
307}
308
309bool btif_config_set_str(const char *section, const char *key, const char *value) {
310  assert(config != NULL);
311  assert(section != NULL);
312  assert(key != NULL);
313  assert(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, size_t *length) {
321  assert(config != NULL);
322  assert(section != NULL);
323  assert(key != NULL);
324  assert(value != NULL);
325  assert(length != NULL);
326
327  std::unique_lock<std::mutex> lock(config_lock);
328  const char *value_str = config_get_string(config, section, key, NULL);
329
330  if (!value_str)
331    return false;
332
333  size_t value_len = strlen(value_str);
334  if ((value_len % 2) != 0 || *length < (value_len / 2))
335    return false;
336
337  for (size_t i = 0; i < value_len; ++i)
338    if (!isxdigit(value_str[i]))
339      return false;
340
341  for (*length = 0; *value_str; value_str += 2, *length += 1)
342    sscanf(value_str, "%02hhx", &value[*length]);
343
344  return true;
345}
346
347size_t btif_config_get_bin_length(const char *section, const char *key) {
348  assert(config != NULL);
349  assert(section != NULL);
350  assert(key != NULL);
351
352  std::unique_lock<std::mutex> lock(config_lock);
353  const char *value_str = config_get_string(config, section, key, NULL);
354  if (!value_str)
355    return 0;
356
357  size_t value_len = strlen(value_str);
358  return ((value_len % 2) != 0) ? 0 : (value_len / 2);
359}
360
361bool btif_config_set_bin(const char *section, const char *key, const uint8_t *value, size_t length) {
362  const char *lookup = "0123456789abcdef";
363
364  assert(config != NULL);
365  assert(section != NULL);
366  assert(key != NULL);
367
368  if (length > 0)
369      assert(value != NULL);
370
371  char *str = (char *)osi_calloc(length * 2 + 1);
372
373  for (size_t i = 0; i < length; ++i) {
374    str[(i * 2) + 0] = lookup[(value[i] >> 4) & 0x0F];
375    str[(i * 2) + 1] = lookup[value[i] & 0x0F];
376  }
377
378  {
379    std::unique_lock<std::mutex> lock(config_lock);
380    config_set_string(config, section, key, str);
381  }
382
383  osi_free(str);
384  return true;
385}
386
387const btif_config_section_iter_t *btif_config_section_begin(void) {
388  assert(config != NULL);
389  return (const btif_config_section_iter_t *)config_section_begin(config);
390}
391
392const btif_config_section_iter_t *btif_config_section_end(void) {
393  assert(config != NULL);
394  return (const btif_config_section_iter_t *)config_section_end(config);
395}
396
397const btif_config_section_iter_t *btif_config_section_next(const btif_config_section_iter_t *section) {
398  assert(config != NULL);
399  assert(section != NULL);
400  return (const btif_config_section_iter_t *)config_section_next((const config_section_node_t *)section);
401}
402
403const char *btif_config_section_name(const btif_config_section_iter_t *section) {
404  assert(config != NULL);
405  assert(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  assert(config != NULL);
411  assert(section != NULL);
412  assert(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  assert(config != NULL);
420  assert(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  assert(config != NULL);
427  assert(config_timer != NULL);
428
429  alarm_cancel(config_timer);
430  btif_config_write(0, NULL);
431}
432
433bool btif_config_clear(void) {
434  assert(config != NULL);
435  assert(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)
444    return false;
445
446  bool ret = config_save(config, CONFIG_FILE_PATH);
447  btif_config_source = RESET;
448  return ret;
449}
450
451static void timer_config_save_cb(UNUSED_ATTR void *data) {
452  // Moving file I/O to btif context instead of timer callback because
453  // it usually takes a lot of time to be completed, introducing
454  // delays during A2DP playback causing blips or choppiness.
455  btif_transfer_context(btif_config_write, 0, NULL, 0, NULL);
456}
457
458static void btif_config_write(UNUSED_ATTR uint16_t event, UNUSED_ATTR char *p_param) {
459  assert(config != NULL);
460  assert(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  assert(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", config_get_string(config, INFO_SECTION,
529                                           FILE_SOURCE, "Original"));
530}
531
532static void btif_config_remove_restricted(config_t* config) {
533  assert(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) && config_has_key(config, section, "Restricted")) {
539        BTIF_TRACE_DEBUG("%s: Removing restricted device %s", __func__, section);
540        config_remove_section(config, section);
541    }
542    snode = config_section_next(snode);
543  }
544}
545
546static bool is_factory_reset(void) {
547  char factory_reset[PROPERTY_VALUE_MAX] = {0};
548  osi_property_get("persist.bluetooth.factoryreset", factory_reset, "false");
549  return strncmp(factory_reset, "true", 4) == 0;
550}
551
552static void delete_config_files(void) {
553  remove(CONFIG_FILE_PATH);
554  remove(CONFIG_BACKUP_PATH);
555  osi_property_set("persist.bluetooth.factoryreset", "false");
556}
557