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 static GSList *ts_list = NULL;
  36
  37 static GResolv *resolv = NULL;
  38 static int resolv_id = 0;
  39
  40 static void resolv_debug(const char *str, void *data)
  41 {
  42         connman_info("%s: %s\n", (const char *) data, str);
  43 }
  44 static void save_timeservers(char **servers)
  45 {
  46         GKeyFile *keyfile;
  47         int cnt;
  48
  49         keyfile = __connman_storage_load_global();
  50         if (keyfile == NULL)
  51                 keyfile = g_key_file_new();
  52
  53         for (cnt = 0; servers != NULL && servers[cnt] != NULL; cnt++);
  54
  55         g_key_file_set_string_list(keyfile, "global", "Timeservers",
  56                            (const gchar **)servers, cnt);
  57
  58         __connman_storage_save_global(keyfile);
  59
  60         g_key_file_free(keyfile);
  61
  62         return;
  63 }
  64
  65 static char **load_timeservers()
  66 {
  67         GKeyFile *keyfile;
  68         GError *error = NULL;
  69         char **servers = NULL;
  70
  71         keyfile = __connman_storage_load_global();
  72         if (keyfile == NULL)
  73                 return NULL;
  74
  75         servers = g_key_file_get_string_list(keyfile, "global",
  76                                                 "Timeservers", NULL, &error);
  77         if (error) {
  78                 DBG("Error loading timeservers: %s", error->message);
  79                 g_error_free(error);
  80         }
  81
  82         g_key_file_free(keyfile);
  83
  84         return servers;
  85 }
  86
  87 static void resolv_result(GResolvResultStatus status, char **results, gpointer user_data)
  88 {
  89         int i;
  90
  91         DBG("status %d", status);
  92
  93         if (status == G_RESOLV_RESULT_STATUS_SUCCESS) {
  94                 if (results != NULL) {
  95                         for (i = 0; results[i]; i++)
  96                                 DBG("result: %s", results[i]);
  97
  98                         __connman_ntp_start(results[0]);
  99
 100                         return;
 101                 }
 102         }
 103
 104         /* If resolving fails, move to the next server */
 105         __connman_timeserver_sync_next();
 106 }
 107
 108 /*
 109  * Once the timeserver list (ts_list) is created, we start querying the
 110  * servers one by one. If resolving fails on one of them, we move to the
 111  * next one. The user can enter either an IP address or a URL for the
 112  * timeserver. We only resolve the urls. Once we have a IP for the NTP
 113  * server, we start querying it for time corrections.
 114  */
 115 void __connman_timeserver_sync_next()
 116 {
 117         char *server;
 118
 119         __connman_ntp_stop();
 120
 121         /* Get the 1st server in the list */
 122         if (ts_list == NULL)
 123                 return;
 124
 125         server = ts_list->data;
 126
 127         ts_list = g_slist_delete_link(ts_list, ts_list);
 128
 129         /* if its a IP , directly query it. */
 130         if (connman_inet_check_ipaddress(server) > 0) {
 131                 DBG("Using timeservers %s", server);
 132
 133                 __connman_ntp_start(server);
 134
 135                 g_free(server);
 136                 return;
 137         }
 138
 139         DBG("Resolving server %s", server);
 140
 141         resolv_id = g_resolv_lookup_hostname(resolv, server,
 142                                                 resolv_result, NULL);
 143
 144         g_free(server);
 145
 146         return;
 147 }
 148
 149 GSList *__connman_timeserver_add_list(GSList *server_list,
 150                 const char *timeserver)
 151 {
 152         GSList *list = server_list;
 153
 154         if (timeserver == NULL)
 155                 return server_list;
 156
 157         while (list != NULL) {
 158                 char *existing_server = list->data;
 159                 if (strcmp(timeserver, existing_server) == 0)
 160                         return server_list;
 161                 list = g_slist_next(list);
 162         }
 163         return g_slist_prepend(server_list, g_strdup(timeserver));
 164 }
 165
 166 /*
 167  * __connman_timeserver_get_all function creates the timeserver
 168  * list which will be used to determine NTP server for time corrections.
 169  * The service settings take priority over the global timeservers.
 170  */
 171 GSList *__connman_timeserver_get_all(struct connman_service *service)
 172 {
 173         GSList *list = NULL;
 174         struct connman_network *network;
 175         char **timeservers;
 176         char **service_ts;
 177         char **service_ts_config;
 178         const char *service_gw;
 179         char **fallback_ts;
 180         int index, i;
 181
 182         service_ts_config = connman_service_get_timeservers_config(service);
 183
 184         /* First add Service Timeservers.Configuration to the list */
 185         for (i = 0; service_ts_config != NULL && service_ts_config[i] != NULL;
 186                         i++)
 187                 list = __connman_timeserver_add_list(list,
 188                                 service_ts_config[i]);
 189
 190         service_ts = connman_service_get_timeservers(service);
 191
 192         /* First add Service Timeservers via DHCP to the list */
 193         for (i = 0; service_ts != NULL && service_ts[i] != NULL; i++)
 194                 list = __connman_timeserver_add_list(list, service_ts[i]);
 195
 196         network = __connman_service_get_network(service);
 197         if (network != NULL) {
 198                 index = connman_network_get_index(network);
 199                 service_gw = __connman_ipconfig_get_gateway_from_index(index,
 200                         CONNMAN_IPCONFIG_TYPE_ALL);
 201
 202                 /* Then add Service Gateway to the list */
 203                 if (service_gw != NULL)
 204                         list = __connman_timeserver_add_list(list, service_gw);
 205         }
 206
 207         /* Then add Global Timeservers to the list */
 208         timeservers = load_timeservers();
 209
 210         for (i = 0; timeservers != NULL && timeservers[i] != NULL; i++)
 211                 list = __connman_timeserver_add_list(list, timeservers[i]);
 212
 213         g_strfreev(timeservers);
 214
 215         fallback_ts = connman_setting_get_string_list("FallbackTimeservers");
 216
 217         /* Lastly add the fallback servers */
 218         for (i = 0; fallback_ts != NULL && fallback_ts[i] != NULL; i++)
 219                 list = __connman_timeserver_add_list(list, fallback_ts[i]);
 220
 221         return g_slist_reverse(list);
 222 }
 223
 224 /*
 225  * This function must be called everytime the default service changes, the
 226  * service timeserver(s) or gatway changes or the global timeserver(s) changes.
 227  */
 228 int __connman_timeserver_sync(struct connman_service *default_service)
 229 {
 230         struct connman_service *service;
 231
 232         if (default_service != NULL)
 233                 service = default_service;
 234         else
 235                 service = __connman_service_get_default();
 236
 237         if (service == NULL)
 238                 return -EINVAL;
 239
 240         if (resolv == NULL)
 241                 return 0;
 242         /*
 243          * Before we start creating the new timeserver list we must stop
 244          * any ongoing ntp query and server resolution.
 245          */
 246
 247         __connman_ntp_stop();
 248
 249         if (resolv_id > 0)
 250                 g_resolv_cancel_lookup(resolv, resolv_id);
 251
 252         g_slist_free_full(ts_list, g_free);
 253
 254         ts_list = __connman_timeserver_get_all(service);
 255
 256         __connman_service_timeserver_changed(service, ts_list);
 257
 258         if (ts_list == NULL) {
 259                 DBG("No timeservers set.");
 260                 return 0;
 261         }
 262
 263         __connman_timeserver_sync_next();
 264
 265         return 0;
 266 }
 267
 268 static int timeserver_start(struct connman_service *service)
 269 {
 270         char **nameservers;
 271         int i;
 272
 273         DBG("service %p", service);
 274
 275         i = __connman_service_get_index(service);
 276         if (i < 0)
 277                 return -EINVAL;
 278
 279         nameservers = connman_service_get_nameservers(service);
 280         if (nameservers == NULL)
 281                 return -EINVAL;
 282
 283         /* Stop an already ongoing resolution, if there is one */
 284         if (resolv != NULL && resolv_id > 0)
 285                 g_resolv_cancel_lookup(resolv, resolv_id);
 286
 287         /* get rid of the old resolver */
 288         if (resolv != NULL) {
 289                 g_resolv_unref(resolv);
 290                 resolv = NULL;
 291         }
 292
 293         resolv = g_resolv_new(i);
 294         if (resolv == NULL) {
 295                 g_strfreev(nameservers);
 296                 return -ENOMEM;
 297         }
 298
 299         if (getenv("CONNMAN_RESOLV_DEBUG"))
 300                 g_resolv_set_debug(resolv, resolv_debug, "RESOLV");
 301
 302         for (i = 0; nameservers[i] != NULL; i++)
 303                 g_resolv_add_nameserver(resolv, nameservers[i], 53, 0);
 304
 305         g_strfreev(nameservers);
 306
 307         return __connman_timeserver_sync(service);
 308 }
 309
 310 static void timeserver_stop()
 311 {
 312         DBG(" ");
 313
 314         if (resolv != NULL) {
 315                 g_resolv_unref(resolv);
 316                 resolv = NULL;
 317         }
 318
 319         g_slist_free_full(ts_list, g_free);
 320
 321         ts_list = NULL;
 322
 323         __connman_ntp_stop();
 324 }
 325
 326 int __connman_timeserver_system_set(char **servers)
 327 {
 328         save_timeservers(servers);
 329
 330         __connman_timeserver_sync(NULL);
 331
 332         return 0;
 333 }
 334
 335 char **__connman_timeserver_system_get()
 336 {
 337         char **servers;
 338
 339         servers = load_timeservers();
 340         return servers;
 341 }
 342
 343 static void default_changed(struct connman_service *default_service)
 344 {
 345         if (default_service != NULL)
 346                 timeserver_start(default_service);
 347         else
 348                 timeserver_stop();
 349 }
 350
 351 static struct connman_notifier timeserver_notifier = {
 352         .name                   = "timeserver",
 353         .default_changed        = default_changed,
 354 };
 355
 356 int __connman_timeserver_init(void)
 357 {
 358         DBG("");
 359
 360         connman_notifier_register(&timeserver_notifier);
 361
 362         return 0;
 363 }
 364
 365 void __connman_timeserver_cleanup(void)
 366 {
 367         DBG("");
 368
 369         connman_notifier_unregister(&timeserver_notifier);
 370 }