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[%d]: %s", i, results[i]);
  92                                 if (i == 0)
  93                                         continue;
  94
  95                                 ts_list = __connman_timeserver_add_list(
  96                                                         ts_list, results[i]);
  97                         }
  98
  99                         __connman_ntp_start(results[0]);
 100
 101                         return;
 102                 }
 103         }
 104
 105         /* If resolving fails, move to the next server */
 106         __connman_timeserver_sync_next();
 107 }
 108
 109 /*
 110  * Once the timeserver list (ts_list) is created, we start querying the
 111  * servers one by one. If resolving fails on one of them, we move to the
 112  * next one. The user can enter either an IP address or a URL for the
 113  * timeserver. We only resolve the urls. Once we have a IP for the NTP
 114  * server, we start querying it for time corrections.
 115  */
 116 void __connman_timeserver_sync_next()
 117 {
 118         char *server;
 119
 120         __connman_ntp_stop();
 121
 122         /* Get the 1st server in the list */
 123         if (ts_list == NULL)
 124                 return;
 125
 126         server = ts_list->data;
 127
 128         ts_list = g_slist_delete_link(ts_list, ts_list);
 129
 130         /* if its a IP , directly query it. */
 131         if (connman_inet_check_ipaddress(server) > 0) {
 132                 DBG("Using timeservers %s", server);
 133
 134                 __connman_ntp_start(server);
 135
 136                 g_free(server);
 137                 return;
 138         }
 139
 140         DBG("Resolving server %s", server);
 141
 142         resolv_id = g_resolv_lookup_hostname(resolv, server,
 143                                                 resolv_result, NULL);
 144
 145         g_free(server);
 146
 147         return;
 148 }
 149
 150 GSList *__connman_timeserver_add_list(GSList *server_list,
 151                 const char *timeserver)
 152 {
 153         GSList *list = server_list;
 154
 155         if (timeserver == NULL)
 156                 return server_list;
 157
 158         while (list != NULL) {
 159                 char *existing_server = list->data;
 160                 if (strcmp(timeserver, existing_server) == 0)
 161                         return server_list;
 162                 list = g_slist_next(list);
 163         }
 164         return g_slist_prepend(server_list, g_strdup(timeserver));
 165 }
 166
 167 /*
 168  * __connman_timeserver_get_all function creates the timeserver
 169  * list which will be used to determine NTP server for time corrections.
 170  * The service settings take priority over the global timeservers.
 171  */
 172 GSList *__connman_timeserver_get_all(struct connman_service *service)
 173 {
 174         GSList *list = NULL;
 175         struct connman_network *network;
 176         char **timeservers;
 177         char **service_ts;
 178         char **service_ts_config;
 179         const char *service_gw;
 180         char **fallback_ts;
 181         int index, i;
 182
 183         service_ts_config = connman_service_get_timeservers_config(service);
 184
 185         /* First add Service Timeservers.Configuration to the list */
 186         for (i = 0; service_ts_config != NULL && service_ts_config[i] != NULL;
 187                         i++)
 188                 list = __connman_timeserver_add_list(list,
 189                                 service_ts_config[i]);
 190
 191         service_ts = connman_service_get_timeservers(service);
 192
 193         /* First add Service Timeservers via DHCP to the list */
 194         for (i = 0; service_ts != NULL && service_ts[i] != NULL; i++)
 195                 list = __connman_timeserver_add_list(list, service_ts[i]);
 196
 197         network = __connman_service_get_network(service);
 198         if (network != NULL) {
 199                 index = connman_network_get_index(network);
 200                 service_gw = __connman_ipconfig_get_gateway_from_index(index,
 201                         CONNMAN_IPCONFIG_TYPE_ALL);
 202
 203                 /* Then add Service Gateway to the list */
 204                 if (service_gw != NULL)
 205                         list = __connman_timeserver_add_list(list, service_gw);
 206         }
 207
 208         /* Then add Global Timeservers to the list */
 209         timeservers = load_timeservers();
 210
 211         for (i = 0; timeservers != NULL && timeservers[i] != NULL; i++)
 212                 list = __connman_timeserver_add_list(list, timeservers[i]);
 213
 214         g_strfreev(timeservers);
 215
 216         fallback_ts = connman_setting_get_string_list("FallbackTimeservers");
 217
 218         /* Lastly add the fallback servers */
 219         for (i = 0; fallback_ts != NULL && fallback_ts[i] != NULL; i++)
 220                 list = __connman_timeserver_add_list(list, fallback_ts[i]);
 221
 222         return g_slist_reverse(list);
 223 }
 224
 225 /*
 226  * This function must be called everytime the default service changes, the
 227  * service timeserver(s) or gatway changes or the global timeserver(s) changes.
 228  */
 229 int __connman_timeserver_sync(struct connman_service *default_service)
 230 {
 231         struct connman_service *service;
 232
 233         if (default_service != NULL)
 234                 service = default_service;
 235         else
 236                 service = __connman_service_get_default();
 237
 238         if (service == NULL)
 239                 return -EINVAL;
 240
 241         if (resolv == NULL)
 242                 return 0;
 243         /*
 244          * Before we start creating the new timeserver list we must stop
 245          * any ongoing ntp query and server resolution.
 246          */
 247
 248         __connman_ntp_stop();
 249
 250         if (resolv_id > 0)
 251                 g_resolv_cancel_lookup(resolv, resolv_id);
 252
 253         g_slist_free_full(ts_list, g_free);
 254
 255         ts_list = __connman_timeserver_get_all(service);
 256
 257         __connman_service_timeserver_changed(service, ts_list);
 258
 259         if (ts_list == NULL) {
 260                 DBG("No timeservers set.");
 261                 return 0;
 262         }
 263
 264         __connman_timeserver_sync_next();
 265
 266         return 0;
 267 }
 268
 269 static int timeserver_start(struct connman_service *service)
 270 {
 271         char **nameservers;
 272         int i;
 273
 274         DBG("service %p", service);
 275
 276         i = __connman_service_get_index(service);
 277         if (i < 0)
 278                 return -EINVAL;
 279
 280         nameservers = connman_service_get_nameservers(service);
 281         if (nameservers == NULL)
 282                 return -EINVAL;
 283
 284         /* Stop an already ongoing resolution, if there is one */
 285         if (resolv != NULL && resolv_id > 0)
 286                 g_resolv_cancel_lookup(resolv, resolv_id);
 287
 288         /* get rid of the old resolver */
 289         if (resolv != NULL) {
 290                 g_resolv_unref(resolv);
 291                 resolv = NULL;
 292         }
 293
 294         resolv = g_resolv_new(i);
 295         if (resolv == NULL) {
 296                 g_strfreev(nameservers);
 297                 return -ENOMEM;
 298         }
 299
 300         if (getenv("CONNMAN_RESOLV_DEBUG"))
 301                 g_resolv_set_debug(resolv, resolv_debug, "RESOLV");
 302
 303         for (i = 0; nameservers[i] != NULL; i++)
 304                 g_resolv_add_nameserver(resolv, nameservers[i], 53, 0);
 305
 306         g_strfreev(nameservers);
 307
 308         return __connman_timeserver_sync(service);
 309 }
 310
 311 static void timeserver_stop()
 312 {
 313         DBG(" ");
 314
 315         if (resolv != NULL) {
 316                 g_resolv_unref(resolv);
 317                 resolv = NULL;
 318         }
 319
 320         g_slist_free_full(ts_list, g_free);
 321
 322         ts_list = NULL;
 323
 324         __connman_ntp_stop();
 325 }
 326
 327 int __connman_timeserver_system_set(char **servers)
 328 {
 329         save_timeservers(servers);
 330
 331         __connman_timeserver_sync(NULL);
 332
 333         return 0;
 334 }
 335
 336 char **__connman_timeserver_system_get()
 337 {
 338         char **servers;
 339
 340         servers = load_timeservers();
 341         return servers;
 342 }
 343
 344 static void default_changed(struct connman_service *default_service)
 345 {
 346         if (default_service != NULL)
 347                 timeserver_start(default_service);
 348         else
 349                 timeserver_stop();
 350 }
 351
 352 static struct connman_notifier timeserver_notifier = {
 353         .name                   = "timeserver",
 354         .default_changed        = default_changed,
 355 };
 356
 357 int __connman_timeserver_init(void)
 358 {
 359         DBG("");
 360
 361         connman_notifier_register(&timeserver_notifier);
 362
 363         return 0;
 364 }
 365
 366 void __connman_timeserver_cleanup(void)
 367 {
 368         DBG("");
 369
 370         connman_notifier_unregister(&timeserver_notifier);
 371 }