btif_config.c revision 9d52f88bfc07556cb01ab3055f5b1242c9b467aa 
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 <assert.h>
22#include <ctype.h>
23#include <pthread.h>
24#include <stdio.h>
25#include <string.h>
26#include <utils/Log.h>
27
28#include "alarm.h"
29#include "btif_config.h"
30#include "btif_config_transcode.h"
31#include "btif_util.h"
32#include "config.h"
33#include "osi.h"
34
35#include "bd.h"
36
37static const char *CONFIG_FILE_PATH = "/data/misc/bluedroid/bt_config.conf";
38static const char *LEGACY_CONFIG_FILE_PATH = "/data/misc/bluedroid/bt_config.xml";
39static const period_ms_t CONFIG_SETTLE_PERIOD_MS = 3000;
40
41static void timer_config_save(void *data);
42
43// TODO(zachoverflow): Move these two functions out, because they are too specific for this file
44// {grumpy-cat/no, monty-python/you-make-me-sad}
45bool btif_get_device_type(const BD_ADDR bd_addr, int *p_device_type)
46{
47    if (p_device_type == NULL)
48        return FALSE;
49
50    bt_bdaddr_t bda;
51    bdcpy(bda.address, bd_addr);
52
53    char bd_addr_str[18] = {0};
54    bd2str(&bda, &bd_addr_str);
55
56    if (!btif_config_get_int(bd_addr_str, "DevType", p_device_type))
57        return FALSE;
58
59    ALOGD("%s: Device [%s] type %d", __FUNCTION__, bd_addr_str, *p_device_type);
60    return TRUE;
61}
62
63bool btif_get_address_type(const BD_ADDR bd_addr, int *p_addr_type)
64{
65    if (p_addr_type == NULL)
66        return FALSE;
67
68    bt_bdaddr_t bda;
69    bdcpy(bda.address, bd_addr);
70
71    char bd_addr_str[18] = {0};
72    bd2str(&bda, &bd_addr_str);
73
74    if (!btif_config_get_int(bd_addr_str, "AddrType", p_addr_type))
75        return FALSE;
76
77    ALOGD("%s: Device [%s] address type %d", __FUNCTION__, bd_addr_str, *p_addr_type);
78    return TRUE;
79}
80
81static pthread_mutex_t lock;  // protects operations on |config|.
82static config_t *config;
83static alarm_t *alarm_timer;
84
85bool btif_config_init(void) {
86  pthread_mutex_init(&lock, NULL);
87  config = config_new(CONFIG_FILE_PATH);
88  if (!config) {
89    ALOGW("%s unable to load config file; attempting to transcode legacy file.", __func__);
90    config = btif_config_transcode(LEGACY_CONFIG_FILE_PATH);
91    if (!config) {
92      ALOGW("%s unable to transcode legacy file, starting unconfigured.", __func__);
93      config = config_new_empty();
94      if (!config) {
95        ALOGE("%s unable to allocate a config object.", __func__);
96        goto error;
97      }
98    }
99
100    if (config_save(config, CONFIG_FILE_PATH))
101      unlink(LEGACY_CONFIG_FILE_PATH);
102  }
103
104  // TODO(sharvil): use a non-wake alarm for this once we have
105  // API support for it. Threre's no need to wake the system to
106  // write back to disk.
107  alarm_timer = alarm_new();
108  if (!alarm_timer) {
109    ALOGE("%s unable to create alarm.", __func__);
110    goto error;
111  }
112
113  return true;
114
115error:;
116  alarm_free(alarm_timer);
117  config_free(config);
118  pthread_mutex_destroy(&lock);
119  alarm_timer = NULL;
120  config = NULL;
121  return false;
122}
123
124void btif_config_cleanup(void) {
125  btif_config_flush();
126
127  alarm_free(alarm_timer);
128  config_free(config);
129  pthread_mutex_destroy(&lock);
130  alarm_timer = NULL;
131  config = NULL;
132}
133
134bool btif_config_has_section(const char *section) {
135  assert(config != NULL);
136  assert(section != NULL);
137
138  pthread_mutex_lock(&lock);
139  bool ret = config_has_section(config, section);
140  pthread_mutex_unlock(&lock);
141
142  return ret;
143}
144
145bool btif_config_exist(const char *section, const char *key) {
146  assert(config != NULL);
147  assert(section != NULL);
148  assert(key != NULL);
149
150  pthread_mutex_lock(&lock);
151  bool ret = config_has_key(config, section, key);
152  pthread_mutex_unlock(&lock);
153
154  return ret;
155}
156
157bool btif_config_get_int(const char *section, const char *key, int *value) {
158  assert(config != NULL);
159  assert(section != NULL);
160  assert(key != NULL);
161  assert(value != NULL);
162
163  pthread_mutex_lock(&lock);
164  bool ret = config_has_key(config, section, key);
165  if (ret)
166    *value = config_get_int(config, section, key, *value);
167  pthread_mutex_unlock(&lock);
168
169  return ret;
170}
171
172bool btif_config_set_int(const char *section, const char *key, int value) {
173  assert(config != NULL);
174  assert(section != NULL);
175  assert(key != NULL);
176
177  pthread_mutex_lock(&lock);
178  config_set_int(config, section, key, value);
179  pthread_mutex_unlock(&lock);
180
181  return true;
182}
183
184bool btif_config_get_str(const char *section, const char *key, char *value, int *length) {
185  assert(config != NULL);
186  assert(section != NULL);
187  assert(key != NULL);
188  assert(value != NULL);
189  assert(length != NULL);
190
191  pthread_mutex_lock(&lock);
192  const char *stored_value = config_get_string(config, section, key, NULL);
193  pthread_mutex_unlock(&lock);
194
195  if (!stored_value)
196    return false;
197
198  strlcpy(value, stored_value, *length);
199  *length = strlen(value);
200
201  return true;
202}
203
204bool btif_config_set_str(const char *section, const char *key, const char *value) {
205  assert(config != NULL);
206  assert(section != NULL);
207  assert(key != NULL);
208  assert(value != NULL);
209
210  pthread_mutex_lock(&lock);
211  config_set_string(config, section, key, value);
212  pthread_mutex_unlock(&lock);
213
214  return true;
215}
216
217bool btif_config_get_bin(const char *section, const char *key, uint8_t *value, size_t *length) {
218  assert(config != NULL);
219  assert(section != NULL);
220  assert(key != NULL);
221  assert(value != NULL);
222  assert(length != NULL);
223
224  pthread_mutex_lock(&lock);
225  const char *value_str = config_get_string(config, section, key, NULL);
226  pthread_mutex_unlock(&lock);
227
228  if (!value_str)
229    return false;
230
231  size_t value_len = strlen(value_str);
232  if ((value_len % 2) != 0 || *length < (value_len / 2))
233    return false;
234
235  for (size_t i = 0; i < value_len; ++i)
236    if (!isxdigit(value_str[i]))
237      return false;
238
239  for (*length = 0; *value_str; value_str += 2, *length += 1)
240    sscanf(value_str, "%02hhx", &value[*length]);
241
242  return true;
243}
244
245size_t btif_config_get_bin_length(const char *section, const char *key) {
246  assert(config != NULL);
247  assert(section != NULL);
248  assert(key != NULL);
249
250  pthread_mutex_lock(&lock);
251  const char *value_str = config_get_string(config, section, key, NULL);
252  pthread_mutex_unlock(&lock);
253
254  if (!value_str)
255    return 0;
256
257  size_t value_len = strlen(value_str);
258  return ((value_len % 2) != 0) ? 0 : (value_len / 2);
259}
260
261bool btif_config_set_bin(const char *section, const char *key, const uint8_t *value, size_t length) {
262  static const char *lookup = "0123456789abcdef";
263
264  assert(config != NULL);
265  assert(section != NULL);
266  assert(key != NULL);
267  assert(value != NULL);
268
269  char *str = (char *)calloc(length * 2 + 1, 1);
270  if (!str)
271    return false;
272
273  for (size_t i = 0; i < length; ++i) {
274    str[(i * 2) + 0] = lookup[(value[i] >> 0) & 0x0F];
275    str[(i * 2) + 1] = lookup[(value[i] >> 4) & 0x0F];
276  }
277
278  pthread_mutex_lock(&lock);
279  config_set_string(config, section, key, str);
280  pthread_mutex_unlock(&lock);
281
282  free(str);
283  return true;
284}
285
286const btif_config_section_iter_t *btif_config_section_begin(void) {
287  assert(config != NULL);
288  return (const btif_config_section_iter_t *)config_section_begin(config);
289}
290
291const btif_config_section_iter_t *btif_config_section_end(void) {
292  assert(config != NULL);
293  return (const btif_config_section_iter_t *)config_section_end(config);
294}
295
296const btif_config_section_iter_t *btif_config_section_next(const btif_config_section_iter_t *section) {
297  assert(config != NULL);
298  assert(section != NULL);
299  return (const btif_config_section_iter_t *)config_section_next((const config_section_node_t *)section);
300}
301
302const char *btif_config_section_name(const btif_config_section_iter_t *section) {
303  assert(config != NULL);
304  assert(section != NULL);
305  return config_section_name((const config_section_node_t *)section);
306}
307
308bool btif_config_remove(const char *section, const char *key) {
309  assert(config != NULL);
310  assert(section != NULL);
311  assert(key != NULL);
312
313  pthread_mutex_lock(&lock);
314  bool ret = config_remove_key(config, section, key);
315  pthread_mutex_unlock(&lock);
316
317  return ret;
318}
319
320void btif_config_save(void) {
321  assert(alarm_timer != NULL);
322  assert(config != NULL);
323
324  alarm_set(alarm_timer, CONFIG_SETTLE_PERIOD_MS, timer_config_save, NULL);
325}
326
327void btif_config_flush(void) {
328  assert(config != NULL);
329  assert(alarm_timer != NULL);
330
331  alarm_cancel(alarm_timer);
332
333  pthread_mutex_lock(&lock);
334  config_save(config, CONFIG_FILE_PATH);
335  pthread_mutex_unlock(&lock);
336}
337
338static void timer_config_save(UNUSED_ATTR void *data) {
339  assert(config != NULL);
340  assert(alarm_timer != NULL);
341
342  // Garbage collection process: the config file accumulates
343  // cached information about remote devices during regular
344  // inquiry scans. We remove some of these junk entries
345  // so the file doesn't grow indefinitely. We have to take care
346  // to make sure we don't remove information about bonded
347  // devices (hence the check for link keys).
348  static const size_t CACHE_MAX = 256;
349  const char *keys[CACHE_MAX];
350  size_t num_keys = 0;
351  size_t total_candidates = 0;
352
353  pthread_mutex_lock(&lock);
354  for (const config_section_node_t *snode = config_section_begin(config); snode != config_section_end(config); snode = config_section_next(snode)) {
355    const char *section = config_section_name(snode);
356    if (!str_is_bdaddr(section))
357      continue;
358
359    if (config_has_key(config, section, "LinkKey") ||
360        config_has_key(config, section, "LE_KEY_PENC") ||
361        config_has_key(config, section, "LE_KEY_PID") ||
362        config_has_key(config, section, "LE_KEY_PCSRK") ||
363        config_has_key(config, section, "LE_KEY_LENC") ||
364        config_has_key(config, section, "LE_KEY_LCSRK"))
365      continue;
366
367    if (num_keys < CACHE_MAX)
368      keys[num_keys++] = section;
369
370    ++total_candidates;
371  }
372
373  if (total_candidates > CACHE_MAX * 2)
374    while (num_keys > 0)
375      config_remove_section(config, keys[--num_keys]);
376
377  config_save(config, CONFIG_FILE_PATH);
378  pthread_mutex_unlock(&lock);
379}
380