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                         DBG("Using timeserver %s", results[0]);
 100
 101                         __connman_ntp_start(results[0]);
 102
 103                         return;
 104                 }
 105         }
 106
 107         /* If resolving fails, move to the next server */
 108         __connman_timeserver_sync_next();
 109 }
 110
 111 /*
 112  * Once the timeserver list (ts_list) is created, we start querying the
 113  * servers one by one. If resolving fails on one of them, we move to the
 114  * next one. The user can enter either an IP address or a URL for the
 115  * timeserver. We only resolve the urls. Once we have a IP for the NTP
 116  * server, we start querying it for time corrections.
 117  */
 118 void __connman_timeserver_sync_next()
 119 {
 120         char *server;
 121
 122         __connman_ntp_stop();
 123
 124         /* Get the 1st server in the list */
 125         if (ts_list == NULL)
 126                 return;
 127
 128         server = ts_list->data;
 129
 130         ts_list = g_slist_delete_link(ts_list, ts_list);
 131
 132         /* if its a IP , directly query it. */
 133         if (connman_inet_check_ipaddress(server) > 0) {
 134                 DBG("Using timeserver %s", server);
 135
 136                 __connman_ntp_start(server);
 137
 138                 g_free(server);
 139                 return;
 140         }
 141
 142         DBG("Resolving server %s", server);
 143
 144         resolv_id = g_resolv_lookup_hostname(resolv, server,
 145                                                 resolv_result, NULL);
 146
 147         g_free(server);
 148
 149         return;
 150 }
 151
 152 GSList *__connman_timeserver_add_list(GSList *server_list,
 153                 const char *timeserver)
 154 {
 155         GSList *list = server_list;
 156
 157         if (timeserver == NULL)
 158                 return server_list;
 159
 160         while (list != NULL) {
 161                 char *existing_server = list->data;
 162                 if (strcmp(timeserver, existing_server) == 0)
 163                         return server_list;
 164                 list = g_slist_next(list);
 165         }
 166         return g_slist_prepend(server_list, g_strdup(timeserver));
 167 }
 168
 169 /*
 170  * __connman_timeserver_get_all function creates the timeserver
 171  * list which will be used to determine NTP server for time corrections.
 172  * The service settings take priority over the global timeservers.
 173  */
 174 GSList *__connman_timeserver_get_all(struct connman_service *service)
 175 {
 176         GSList *list = NULL;
 177         struct connman_network *network;
 178         char **timeservers;
 179         char **service_ts;
 180         char **service_ts_config;
 181         const char *service_gw;
 182         char **fallback_ts;
 183         int index, i;
 184
 185         service_ts_config = connman_service_get_timeservers_config(service);
 186
 187         /* First add Service Timeservers.Configuration to the list */
 188         for (i = 0; service_ts_config != NULL && service_ts_config[i] != NULL;
 189                         i++)
 190                 list = __connman_timeserver_add_list(list,
 191                                 service_ts_config[i]);
 192
 193         service_ts = connman_service_get_timeservers(service);
 194
 195         /* First add Service Timeservers via DHCP to the list */
 196         for (i = 0; service_ts != NULL && service_ts[i] != NULL; i++)
 197                 list = __connman_timeserver_add_list(list, service_ts[i]);
 198
 199         network = __connman_service_get_network(service);
 200         if (network != NULL) {
 201                 index = connman_network_get_index(network);
 202                 service_gw = __connman_ipconfig_get_gateway_from_index(index,
 203                         CONNMAN_IPCONFIG_TYPE_ALL);
 204
 205                 /* Then add Service Gateway to the list */
 206                 if (service_gw != NULL)
 207                         list = __connman_timeserver_add_list(list, service_gw);
 208         }
 209
 210         /* Then add Global Timeservers to the list */
 211         timeservers = load_timeservers();
 212
 213         for (i = 0; timeservers != NULL && timeservers[i] != NULL; i++)
 214                 list = __connman_timeserver_add_list(list, timeservers[i]);
 215
 216         g_strfreev(timeservers);
 217
 218         fallback_ts = connman_setting_get_string_list("FallbackTimeservers");
 219
 220         /* Lastly add the fallback servers */
 221         for (i = 0; fallback_ts != NULL && fallback_ts[i] != NULL; i++)
 222                 list = __connman_timeserver_add_list(list, fallback_ts[i]);
 223
 224         return g_slist_reverse(list);
 225 }
 226
 227 /*
 228  * This function must be called everytime the default service changes, the
 229  * service timeserver(s) or gatway changes or the global timeserver(s) changes.
 230  */
 231 int __connman_timeserver_sync(struct connman_service *default_service)
 232 {
 233         struct connman_service *service;
 234
 235         if (default_service != NULL)
 236                 service = default_service;
 237         else
 238                 service = __connman_service_get_default();
 239
 240         if (service == NULL)
 241                 return -EINVAL;
 242
 243         if (resolv == NULL)
 244                 return 0;
 245         /*
 246          * Before we start creating the new timeserver list we must stop
 247          * any ongoing ntp query and server resolution.
 248          */
 249
 250         __connman_ntp_stop();
 251
 252         if (resolv_id > 0)
 253                 g_resolv_cancel_lookup(resolv, resolv_id);
 254
 255         g_slist_free_full(ts_list, g_free);
 256
 257         ts_list = __connman_timeserver_get_all(service);
 258
 259         __connman_service_timeserver_changed(service, ts_list);
 260
 261         if (ts_list == NULL) {
 262                 DBG("No timeservers set.");
 263                 return 0;
 264         }
 265
 266         __connman_timeserver_sync_next();
 267
 268         return 0;
 269 }
 270
 271 static int timeserver_start(struct connman_service *service)
 272 {
 273         char **nameservers;
 274         int i;
 275
 276         DBG("service %p", service);
 277
 278         i = __connman_service_get_index(service);
 279         if (i < 0)
 280                 return -EINVAL;
 281
 282         nameservers = connman_service_get_nameservers(service);
 283         if (nameservers == NULL)
 284                 return -EINVAL;
 285
 286         /* Stop an already ongoing resolution, if there is one */
 287         if (resolv != NULL && resolv_id > 0)
 288                 g_resolv_cancel_lookup(resolv, resolv_id);
 289
 290         /* get rid of the old resolver */
 291         if (resolv != NULL) {
 292                 g_resolv_unref(resolv);
 293                 resolv = NULL;
 294         }
 295
 296         resolv = g_resolv_new(i);
 297         if (resolv == NULL) {
 298                 g_strfreev(nameservers);
 299                 return -ENOMEM;
 300         }
 301
 302         if (getenv("CONNMAN_RESOLV_DEBUG"))
 303                 g_resolv_set_debug(resolv, resolv_debug, "RESOLV");
 304
 305         for (i = 0; nameservers[i] != NULL; i++)
 306                 g_resolv_add_nameserver(resolv, nameservers[i], 53, 0);
 307
 308         g_strfreev(nameservers);
 309
 310         return __connman_timeserver_sync(service);
 311 }
 312
 313 static void timeserver_stop()
 314 {
 315         DBG(" ");
 316
 317         if (resolv != NULL) {
 318                 g_resolv_unref(resolv);
 319                 resolv = NULL;
 320         }
 321
 322         g_slist_free_full(ts_list, g_free);
 323
 324         ts_list = NULL;
 325
 326         __connman_ntp_stop();
 327 }
 328
 329 int __connman_timeserver_system_set(char **servers)
 330 {
 331         save_timeservers(servers);
 332
 333         __connman_timeserver_sync(NULL);
 334
 335         return 0;
 336 }
 337
 338 char **__connman_timeserver_system_get()
 339 {
 340         char **servers;
 341
 342         servers = load_timeservers();
 343         return servers;
 344 }
 345
 346 static void default_changed(struct connman_service *default_service)
 347 {
 348         if (default_service != NULL)
 349                 timeserver_start(default_service);
 350         else
 351                 timeserver_stop();
 352 }
 353
 354 static struct connman_notifier timeserver_notifier = {
 355         .name                   = "timeserver",
 356         .default_changed        = default_changed,
 357 };
 358
 359 int __connman_timeserver_init(void)
 360 {
 361         DBG("");
 362
 363         connman_notifier_register(&timeserver_notifier);
 364
 365         return 0;
 366 }
 367
 368 void __connman_timeserver_cleanup(void)
 369 {
 370         DBG("");
 371
 372         connman_notifier_unregister(&timeserver_notifier);
 373 }