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