src/timeserver.c

   1 /*
   2  *
   3  *  Connection Manager
   4  *
   5  *  Copyright (C) 2007-2012  Intel Corporation. All rights reserved.
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 as
   9  *  published by the Free Software Foundation.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <errno.h>
  27
  28 #include <glib.h>
  29 #include <stdlib.h>
  30 #include <gweb/gresolv.h>
  31 #include <netdb.h>
  32
  33 #include "connman.h"
  34
  35 #define TS_RECHECK_INTERVAL     7200
  36
  37 static GSList *ts_list = NULL;
  38 static char *ts_current = NULL;
  39 static int ts_recheck_id = 0;
  40
  41 static GResolv *resolv = NULL;
  42 static int resolv_id = 0;
  43
  44 static void resolv_debug(const char *str, void *data)
  45 {
  46         connman_info("%s: %s\n", (const char *) data, str);
  47 }
  48 static void save_timeservers(char **servers)
  49 {
  50         GKeyFile *keyfile;
  51         int cnt;
  52
  53         keyfile = __connman_storage_load_global();
  54         if (keyfile == NULL)
  55                 keyfile = g_key_file_new();
  56
  57         for (cnt = 0; servers != NULL && servers[cnt] != NULL; cnt++);
  58
  59         g_key_file_set_string_list(keyfile, "global", "Timeservers",
  60                            (const gchar **)servers, cnt);
  61
  62         __connman_storage_save_global(keyfile);
  63
  64         g_key_file_free(keyfile);
  65
  66         return;
  67 }
  68
  69 static char **load_timeservers()
  70 {
  71         GKeyFile *keyfile;
  72         char **servers = NULL;
  73
  74         keyfile = __connman_storage_load_global();
  75         if (keyfile == NULL)
  76                 return NULL;
  77
  78         servers = g_key_file_get_string_list(keyfile, "global",
  79                                                 "Timeservers", NULL, NULL);
  80
  81         g_key_file_free(keyfile);
  82
  83         return servers;
  84 }
  85
  86 static void resolv_result(GResolvResultStatus status, char **results, gpointer user_data)
  87 {
  88         int i;
  89
  90         DBG("status %d", status);
  91
  92         if (status == G_RESOLV_RESULT_STATUS_SUCCESS) {
  93                 if (results != NULL) {
  94                         for (i = 0; results[i]; i++) {
  95                                 DBG("result[%d]: %s", i, results[i]);
  96                                 if (i == 0)
  97                                         continue;
  98
  99                                 ts_list = __connman_timeserver_add_list(
 100                                                         ts_list, results[i]);
 101                         }
 102
 103                         DBG("Using timeserver %s", results[0]);
 104
 105                         __connman_ntp_start(results[0]);
 106
 107                         return;
 108                 }
 109         }
 110
 111         /* If resolving fails, move to the next server */
 112         __connman_timeserver_sync_next();
 113 }
 114
 115 /*
 116  * Once the timeserver list (ts_list) is created, we start querying the
 117  * servers one by one. If resolving fails on one of them, we move to the
 118  * next one. The user can enter either an IP address or a URL for the
 119  * timeserver. We only resolve the urls. Once we have a IP for the NTP
 120  * server, we start querying it for time corrections.
 121  */
 122 void __connman_timeserver_sync_next()
 123 {
 124         if (ts_current != NULL) {
 125                 g_free(ts_current);
 126                 ts_current = NULL;
 127         }
 128
 129         __connman_ntp_stop();
 130
 131         /* Get the 1st server in the list */
 132         if (ts_list == NULL)
 133                 return;
 134
 135         ts_current = ts_list->data;
 136
 137         ts_list = g_slist_delete_link(ts_list, ts_list);
 138
 139         /* if its a IP , directly query it. */
 140         if (connman_inet_check_ipaddress(ts_current) > 0) {
 141                 DBG("Using timeserver %s", ts_current);
 142
 143                 __connman_ntp_start(ts_current);
 144
 145                 return;
 146         }
 147
 148         DBG("Resolving server %s", ts_current);
 149
 150         resolv_id = g_resolv_lookup_hostname(resolv, ts_current,
 151                                                 resolv_result, NULL);
 152
 153         return;
 154 }
 155
 156 GSList *__connman_timeserver_add_list(GSList *server_list,
 157                 const char *timeserver)
 158 {
 159         GSList *list = server_list;
 160
 161         if (timeserver == NULL)
 162                 return server_list;
 163
 164         while (list != NULL) {
 165                 char *existing_server = list->data;
 166                 if (strcmp(timeserver, existing_server) == 0)
 167                         return server_list;
 168                 list = g_slist_next(list);
 169         }
 170         return g_slist_prepend(server_list, g_strdup(timeserver));
 171 }
 172
 173 /*
 174  * __connman_timeserver_get_all function creates the timeserver
 175  * list which will be used to determine NTP server for time corrections.
 176  * The service settings take priority over the global timeservers.
 177  */
 178 GSList *__connman_timeserver_get_all(struct connman_service *service)
 179 {
 180         GSList *list = NULL;
 181         struct connman_network *network;
 182         char **timeservers;
 183         char **service_ts;
 184         char **service_ts_config;
 185         const char *service_gw;
 186         char **fallback_ts;
 187         int index, i;
 188
 189         if (__connman_clock_timeupdates() == TIME_UPDATES_MANUAL)
 190                 return NULL;
 191
 192         service_ts_config = connman_service_get_timeservers_config(service);
 193
 194         /* First add Service Timeservers.Configuration to the list */
 195         for (i = 0; service_ts_config != NULL && service_ts_config[i] != NULL;
 196                         i++)
 197                 list = __connman_timeserver_add_list(list,
 198                                 service_ts_config[i]);
 199
 200         service_ts = connman_service_get_timeservers(service);
 201
 202         /* First add Service Timeservers via DHCP to the list */
 203         for (i = 0; service_ts != NULL && service_ts[i] != NULL; i++)
 204                 list = __connman_timeserver_add_list(list, service_ts[i]);
 205
 206         network = __connman_service_get_network(service);
 207         if (network != NULL) {
 208                 index = connman_network_get_index(network);
 209                 service_gw = __connman_ipconfig_get_gateway_from_index(index,
 210                         CONNMAN_IPCONFIG_TYPE_ALL);
 211
 212                 /* Then add Service Gateway to the list */
 213                 if (service_gw != NULL)
 214                         list = __connman_timeserver_add_list(list, service_gw);
 215         }
 216
 217         /* Then add Global Timeservers to the list */
 218         timeservers = load_timeservers();
 219
 220         for (i = 0; timeservers != NULL && timeservers[i] != NULL; i++)
 221                 list = __connman_timeserver_add_list(list, timeservers[i]);
 222
 223         g_strfreev(timeservers);
 224
 225         fallback_ts = connman_setting_get_string_list("FallbackTimeservers");
 226
 227         /* Lastly add the fallback servers */
 228         for (i = 0; fallback_ts != NULL && fallback_ts[i] != NULL; i++)
 229                 list = __connman_timeserver_add_list(list, fallback_ts[i]);
 230
 231         return g_slist_reverse(list);
 232 }
 233
 234 static gboolean ts_recheck(void *user_data)
 235 {
 236         GSList *ts;
 237
 238         ts = __connman_timeserver_get_all(__connman_service_get_default());
 239
 240         if (ts == NULL) {
 241                 DBG("timeservers disabled");
 242
 243                 return TRUE;
 244         }
 245
 246         if (g_strcmp0(ts_current, ts->data) != 0) {
 247                 DBG("current %s preferred %s", ts_current, (char *)ts->data);
 248
 249                 g_slist_free_full(ts, g_free);
 250
 251                 __connman_timeserver_sync(NULL);
 252
 253                 return FALSE;
 254         }
 255
 256         DBG("");
 257
 258         g_slist_free_full(ts, g_free);
 259
 260         return TRUE;
 261 }
 262
 263 static void ts_recheck_disable(void)
 264 {
 265         if (ts_recheck_id == 0)
 266                 return;
 267
 268         g_source_remove(ts_recheck_id);
 269         ts_recheck_id = 0;
 270
 271         if (ts_current != NULL) {
 272                 g_free(ts_current);
 273                 ts_current = NULL;
 274         }
 275 }
 276
 277 static void ts_recheck_enable(void)
 278 {
 279         if (ts_recheck_id > 0)
 280                 return;
 281
 282         ts_recheck_id = g_timeout_add_seconds(TS_RECHECK_INTERVAL, ts_recheck,
 283                         NULL);
 284 }
 285
 286 /*
 287  * This function must be called everytime the default service changes, the
 288  * service timeserver(s) or gatway changes or the global timeserver(s) changes.
 289  */
 290 int __connman_timeserver_sync(struct connman_service *default_service)
 291 {
 292         struct connman_service *service;
 293
 294         if (default_service != NULL)
 295                 service = default_service;
 296         else
 297                 service = __connman_service_get_default();
 298
 299         if (service == NULL)
 300                 return -EINVAL;
 301
 302         if (resolv == NULL)
 303                 return 0;
 304         /*
 305          * Before we start creating the new timeserver list we must stop
 306          * any ongoing ntp query and server resolution.
 307          */
 308
 309         __connman_ntp_stop();
 310
 311         ts_recheck_disable();
 312
 313         if (resolv_id > 0)
 314                 g_resolv_cancel_lookup(resolv, resolv_id);
 315
 316         g_slist_free_full(ts_list, g_free);
 317
 318         ts_list = __connman_timeserver_get_all(service);
 319
 320         __connman_service_timeserver_changed(service, ts_list);
 321
 322         if (ts_list == NULL) {
 323                 DBG("No timeservers set.");
 324                 return 0;
 325         }
 326
 327         ts_recheck_enable();
 328
 329         __connman_timeserver_sync_next();
 330
 331         return 0;
 332 }
 333
 334 static int timeserver_start(struct connman_service *service)
 335 {
 336         char **nameservers;
 337         int i;
 338
 339         DBG("service %p", service);
 340
 341         i = __connman_service_get_index(service);
 342         if (i < 0)
 343                 return -EINVAL;
 344
 345         nameservers = connman_service_get_nameservers(service);
 346         if (nameservers == NULL)
 347                 return -EINVAL;
 348
 349         /* Stop an already ongoing resolution, if there is one */
 350         if (resolv != NULL && resolv_id > 0)
 351                 g_resolv_cancel_lookup(resolv, resolv_id);
 352
 353         /* get rid of the old resolver */
 354         if (resolv != NULL) {
 355                 g_resolv_unref(resolv);
 356                 resolv = NULL;
 357         }
 358
 359         resolv = g_resolv_new(i);
 360         if (resolv == NULL) {
 361                 g_strfreev(nameservers);
 362                 return -ENOMEM;
 363         }
 364
 365         if (getenv("CONNMAN_RESOLV_DEBUG"))
 366                 g_resolv_set_debug(resolv, resolv_debug, "RESOLV");
 367
 368         for (i = 0; nameservers[i] != NULL; i++)
 369                 g_resolv_add_nameserver(resolv, nameservers[i], 53, 0);
 370
 371         g_strfreev(nameservers);
 372
 373         return __connman_timeserver_sync(service);
 374 }
 375
 376 static void timeserver_stop()
 377 {
 378         DBG(" ");
 379
 380         if (resolv != NULL) {
 381                 g_resolv_unref(resolv);
 382                 resolv = NULL;
 383         }
 384
 385         g_slist_free_full(ts_list, g_free);
 386
 387         ts_list = NULL;
 388
 389         __connman_ntp_stop();
 390
 391         ts_recheck_disable();
 392 }
 393
 394 int __connman_timeserver_system_set(char **servers)
 395 {
 396         save_timeservers(servers);
 397
 398         __connman_timeserver_sync(NULL);
 399
 400         return 0;
 401 }
 402
 403 char **__connman_timeserver_system_get()
 404 {
 405         char **servers;
 406
 407         servers = load_timeservers();
 408         return servers;
 409 }
 410
 411 static void default_changed(struct connman_service *default_service)
 412 {
 413         if (default_service != NULL)
 414                 timeserver_start(default_service);
 415         else
 416                 timeserver_stop();
 417 }
 418
 419 static struct connman_notifier timeserver_notifier = {
 420         .name                   = "timeserver",
 421         .default_changed        = default_changed,
 422 };
 423
 424 int __connman_timeserver_init(void)
 425 {
 426         DBG("");
 427
 428         connman_notifier_register(&timeserver_notifier);
 429
 430         return 0;
 431 }
 432
 433 void __connman_timeserver_cleanup(void)
 434 {
 435         DBG("");
 436
 437         connman_notifier_unregister(&timeserver_notifier);
 438 }