src/timezone.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 #include <stdio.h>
  28 #include <fcntl.h>
  29 #include <unistd.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <dirent.h>
  33 #include <sys/stat.h>
  34 #include <sys/mman.h>
  35 #include <sys/inotify.h>
  36
  37 #include <glib.h>
  38
  39 #include "connman.h"
  40
  41 #define ETC_SYSCONFIG_CLOCK     "/etc/sysconfig/clock"
  42 #define USR_SHARE_ZONEINFO      "/usr/share/zoneinfo"
  43 #define USR_SHARE_ZONEINFO_MAP  USR_SHARE_ZONEINFO "/zone1970.tab"
  44
  45 static char *read_key_file(const char *pathname, const char *key)
  46 {
  47         struct stat st;
  48         char *map, *ptr, *str;
  49         off_t ptrlen, keylen;
  50         int fd;
  51
  52         fd = open(pathname, O_RDONLY | O_CLOEXEC);
  53         if (fd < 0)
  54                 return NULL;
  55
  56         if (fstat(fd, &st) < 0) {
  57                 close(fd);
  58                 return NULL;
  59         }
  60
  61         map = mmap(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
  62         if (!map || map == MAP_FAILED) {
  63                 close(fd);
  64                 return NULL;
  65         }
  66
  67         ptr = map;
  68         ptrlen = st.st_size;
  69         keylen = strlen(key);
  70
  71         while (ptrlen > keylen + 1) {
  72                 int cmp = strncmp(ptr, key, keylen);
  73
  74                 if (cmp == 0) {
  75                         if (ptr == map)
  76                                 break;
  77
  78                         if (*(ptr - 1) == '\n' && *(ptr + keylen) == '=')
  79                                 break;
  80                 }
  81
  82                 ptr = memchr(ptr + 1, key[0], ptrlen - 1);
  83                 if (!ptr)
  84                         break;
  85
  86                 ptrlen = st.st_size - (ptr - map);
  87         }
  88
  89         if (ptr) {
  90                 char *end, *val;
  91
  92                 ptrlen = st.st_size - (ptr - map);
  93
  94                 end = memchr(ptr, '\n', ptrlen);
  95                 if (end)
  96                         ptrlen = end - ptr;
  97
  98                 val = memchr(ptr, '"', ptrlen);
  99                 if (val) {
 100                         end = memchr(val + 1, '"', end - val - 1);
 101                         if (end)
 102                                 str = g_strndup(val + 1, end - val - 1);
 103                         else
 104                                 str = NULL;
 105                 } else
 106                         str = g_strndup(ptr + keylen + 1, ptrlen - keylen - 1);
 107         } else
 108                 str = NULL;
 109
 110         munmap(map, st.st_size);
 111
 112         close(fd);
 113
 114         return str;
 115 }
 116
 117 static int compare_file(void *src_map, struct stat *src_st,
 118                                                 const char *pathname)
 119 {
 120         struct stat dst_st;
 121         void *dst_map;
 122         int fd, result;
 123
 124         fd = open(pathname, O_RDONLY | O_CLOEXEC);
 125         if (fd < 0)
 126                 return -1;
 127
 128         if (fstat(fd, &dst_st) < 0) {
 129                 close(fd);
 130                 return -1;
 131         }
 132
 133         if (src_st->st_size != dst_st.st_size) {
 134                 close(fd);
 135                 return -1;
 136         }
 137
 138         dst_map = mmap(0, dst_st.st_size, PROT_READ, MAP_SHARED, fd, 0);
 139         if (!dst_map || dst_map == MAP_FAILED) {
 140                 close(fd);
 141                 return -1;
 142         }
 143
 144         result = memcmp(src_map, dst_map, src_st->st_size);
 145
 146         munmap(dst_map, dst_st.st_size);
 147
 148         close(fd);
 149
 150         return result;
 151 }
 152
 153 static char *find_origin(void *src_map, struct stat *src_st,
 154                                 const char *basepath, const char *subpath)
 155 {
 156         DIR *dir;
 157         struct dirent *d;
 158         char *str, pathname[PATH_MAX];
 159         struct stat buf;
 160         int ret;
 161
 162         if (!subpath)
 163                 strncpy(pathname, basepath, sizeof(pathname) - 1);
 164         else
 165                 snprintf(pathname, sizeof(pathname),
 166                                         "%s/%s", basepath, subpath);
 167
 168         dir = opendir(pathname);
 169         if (!dir)
 170                 return NULL;
 171
 172         while ((d = readdir(dir))) {
 173                 if (strcmp(d->d_name, ".") == 0 ||
 174                                 strcmp(d->d_name, "..") == 0 ||
 175                                 strcmp(d->d_name, "posix") == 0 ||
 176                                 strcmp(d->d_name, "right") == 0)
 177                         continue;
 178
 179                 switch (d->d_type) {
 180                 case DT_REG:
 181                         if (!subpath)
 182                                 snprintf(pathname, PATH_MAX,
 183                                                 "%s/%s", basepath, d->d_name);
 184                         else
 185                                 snprintf(pathname, PATH_MAX,
 186                                                 "%s/%s/%s", basepath,
 187                                                         subpath, d->d_name);
 188
 189                         if (compare_file(src_map, src_st, pathname) == 0) {
 190                                 if (!subpath)
 191                                         str = g_strdup(d->d_name);
 192                                 else
 193                                         str = g_strdup_printf("%s/%s",
 194                                                         subpath, d->d_name);
 195                                 closedir(dir);
 196                                 return str;
 197                         }
 198                         break;
 199                 case DT_UNKNOWN:
 200                         /*
 201                          * If there is no d_type support use fstatat()
 202                          * to check if d_name is directory
 203                          */
 204                         ret = fstatat(dirfd(dir), d->d_name, &buf, 0);
 205                         if (ret < 0)
 206                                 continue;
 207                         if ((buf.st_mode & S_IFDIR) == 0)
 208                                 continue;
 209                         /* fall through */
 210                 case DT_DIR:
 211                         if (!subpath)
 212                                 strncpy(pathname, d->d_name, sizeof(pathname));
 213                         else
 214                                 snprintf(pathname, sizeof(pathname),
 215                                                 "%s/%s", subpath, d->d_name);
 216
 217                         str = find_origin(src_map, src_st, basepath, pathname);
 218                         if (str) {
 219                                 closedir(dir);
 220                                 return str;
 221                         }
 222                         break;
 223                 }
 224         }
 225
 226         closedir(dir);
 227
 228         return NULL;
 229 }
 230
 231 static char *get_timezone_alpha2(const char *zone)
 232 {
 233         GIOChannel *channel;
 234         struct stat st;
 235         char **tokens;
 236         char *line;
 237         char *alpha2 = NULL;
 238         gsize len;
 239         int fd;
 240
 241         if (!zone)
 242                 return NULL;
 243
 244         fd = open(USR_SHARE_ZONEINFO_MAP, O_RDONLY | O_CLOEXEC);
 245         if (fd < 0) {
 246                 connman_warn("failed to open zoneinfo map %s",
 247                                                         USR_SHARE_ZONEINFO_MAP);
 248                 return NULL;
 249         }
 250
 251         if (fstat(fd, &st) < 0 || !S_ISREG(st.st_mode)) {
 252                 connman_warn("zoneinfo map does not exist/not regular file");
 253                 close(fd);
 254                 return NULL;
 255         }
 256
 257         channel = g_io_channel_unix_new(fd);
 258         if (!channel) {
 259                 connman_warn("failed to create io channel for %s",
 260                                                         USR_SHARE_ZONEINFO_MAP);
 261                 close(fd);
 262                 return NULL;
 263         }
 264
 265         DBG("read %s for %s", USR_SHARE_ZONEINFO_MAP, zone);
 266         g_io_channel_set_encoding(channel, "UTF-8", NULL);
 267
 268         while (g_io_channel_read_line(channel, &line, &len, NULL, NULL) ==
 269                                                         G_IO_STATUS_NORMAL) {
 270                 if (!line || !*line || *line == '#' || *line == '\n') {
 271                         g_free(line);
 272                         continue;
 273                 }
 274
 275                 /* File format: Countrycodes Coordinates TZ Comments */
 276                 tokens = g_strsplit_set(line, " \t", 4);
 277                 if (!tokens) {
 278                         connman_warn("line %s failed to parse", line);
 279                         g_free(line);
 280                         continue;
 281                 }
 282
 283                 if (g_strv_length(tokens) >= 3 && !g_strcmp0(
 284                                                 g_strstrip(tokens[2]), zone)) {
 285                         /*
 286                          * Multiple country codes can be listed, use the first
 287                          * 2 chars.
 288                          */
 289                         alpha2 = g_strndup(g_strstrip(tokens[0]), 2);
 290                 }
 291
 292                 g_strfreev(tokens);
 293                 g_free(line);
 294
 295                 if (alpha2) {
 296                         if (strlen(alpha2) != 2) {
 297                                 connman_warn("Invalid ISO3166 code %s", alpha2);
 298                                 g_free(alpha2);
 299                                 alpha2 = NULL;
 300                         } else {
 301                                 DBG("Zone %s ISO3166 country code %s", zone,
 302                                                                         alpha2);
 303                         }
 304
 305                         break;
 306                 }
 307         }
 308
 309         g_io_channel_unref(channel);
 310         close(fd);
 311
 312         return alpha2;
 313 }
 314
 315 char *__connman_timezone_lookup(void)
 316 {
 317         struct stat st;
 318         void *map;
 319         int fd;
 320         char *zone;
 321         char *alpha2;
 322
 323         zone = read_key_file(ETC_SYSCONFIG_CLOCK, "ZONE");
 324
 325         DBG("sysconfig zone %s", zone);
 326
 327         fd = open(connman_setting_get_string("Localtime"),
 328                                                         O_RDONLY | O_CLOEXEC);
 329         if (fd < 0) {
 330                 g_free(zone);
 331                 return NULL;
 332         }
 333
 334         if (fstat(fd, &st) < 0)
 335                 goto done;
 336
 337         if (S_ISREG(st.st_mode)) {
 338                 map = mmap(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
 339                 if (!map || map == MAP_FAILED) {
 340                         g_free(zone);
 341                         zone = NULL;
 342
 343                         goto done;
 344                 }
 345
 346                 if (zone) {
 347                         char pathname[PATH_MAX];
 348
 349                         snprintf(pathname, PATH_MAX, "%s/%s",
 350                                                 USR_SHARE_ZONEINFO, zone);
 351
 352                         if (compare_file(map, &st, pathname) != 0) {
 353                                 g_free(zone);
 354                                 zone = NULL;
 355                         }
 356                 }
 357
 358                 if (!zone)
 359                         zone = find_origin(map, &st, USR_SHARE_ZONEINFO, NULL);
 360
 361                 munmap(map, st.st_size);
 362         } else {
 363                 g_free(zone);
 364                 zone = NULL;
 365         }
 366
 367 done:
 368         close(fd);
 369
 370         DBG("localtime zone %s", zone);
 371
 372         if (connman_setting_get_bool("RegdomFollowsTimezone")) {
 373                 alpha2 = get_timezone_alpha2(zone);
 374                 if (alpha2) {
 375                         DBG("change regdom to %s", alpha2);
 376                         connman_technology_set_regdom(alpha2);
 377                         g_free(alpha2);
 378                 }
 379         }
 380
 381         return zone;
 382 }
 383
 384 static int write_file(void *src_map, struct stat *src_st, const char *pathname)
 385 {
 386         struct stat st;
 387         int fd;
 388         ssize_t written;
 389
 390         DBG("pathname %s", pathname);
 391
 392         if (lstat(pathname, &st) == 0) {
 393                 if (S_ISLNK(st.st_mode))
 394                         unlink(pathname);
 395         }
 396
 397         fd = open(pathname, O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC, 0644);
 398         if (fd < 0)
 399                 return -EIO;
 400
 401         written = write(fd, src_map, src_st->st_size);
 402
 403         close(fd);
 404
 405         if (written < 0)
 406                 return -EIO;
 407
 408         return 0;
 409 }
 410
 411 int __connman_timezone_change(const char *zone)
 412 {
 413         struct stat st;
 414         char *map, pathname[PATH_MAX];
 415         int fd, err;
 416
 417         DBG("zone %s", zone);
 418
 419         snprintf(pathname, PATH_MAX, "%s/%s", USR_SHARE_ZONEINFO, zone);
 420
 421         fd = open(pathname, O_RDONLY | O_CLOEXEC);
 422         if (fd < 0)
 423                 return -EINVAL;
 424
 425         if (fstat(fd, &st) < 0) {
 426                 close(fd);
 427                 return -EIO;
 428         }
 429
 430         map = mmap(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
 431         if (!map || map == MAP_FAILED) {
 432                 close(fd);
 433                 return -EIO;
 434         }
 435
 436         err = write_file(map, &st, connman_setting_get_string("Localtime"));
 437
 438         munmap(map, st.st_size);
 439
 440         close(fd);
 441
 442         return err;
 443 }
 444
 445 static guint inotify_watch = 0;
 446
 447 static gboolean inotify_data(GIOChannel *channel, GIOCondition cond,
 448                                                         gpointer user_data)
 449 {
 450         char buffer[256];
 451         void *ptr = buffer;
 452         GIOStatus status;
 453         gsize bytes_read;
 454
 455         DBG("");
 456
 457         if (cond & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
 458                 inotify_watch = 0;
 459                 return FALSE;
 460         }
 461
 462         status = g_io_channel_read_chars(channel, buffer, sizeof(buffer),
 463                                                         &bytes_read, NULL);
 464
 465         switch (status) {
 466         case G_IO_STATUS_NORMAL:
 467                 break;
 468         case G_IO_STATUS_AGAIN:
 469                 return TRUE;
 470         default:
 471                 inotify_watch = 0;
 472                 return FALSE;
 473         }
 474
 475         DBG("bytes read %zd", bytes_read);
 476
 477         while (bytes_read > 0) {
 478                 struct inotify_event *event = ptr;
 479
 480                 if (bytes_read < sizeof(*event))
 481                         break;
 482
 483                 ptr += sizeof(*event);
 484                 bytes_read -= sizeof(*event);
 485
 486                 if (event->len == 0)
 487                         continue;
 488
 489                 if (bytes_read < event->len)
 490                         break;
 491
 492                 ptr += event->len;
 493                 bytes_read -= event->len;
 494
 495                 if (g_strcmp0(event->name, "localtime") == 0)
 496                         __connman_clock_update_timezone();
 497         }
 498
 499         return TRUE;
 500 }
 501
 502 int __connman_timezone_init(void)
 503 {
 504         GIOChannel *channel;
 505         char *dirname;
 506         int fd, wd;
 507
 508         DBG("");
 509
 510         fd = inotify_init1(IN_NONBLOCK | IN_CLOEXEC);
 511         if (fd < 0)
 512                 return -EIO;
 513
 514         channel = g_io_channel_unix_new(fd);
 515         if (!channel) {
 516                 close(fd);
 517                 return -EIO;
 518         }
 519
 520         g_io_channel_set_close_on_unref(channel, TRUE);
 521         g_io_channel_set_encoding(channel, NULL, NULL);
 522         g_io_channel_set_buffered(channel, FALSE);
 523
 524         inotify_watch = g_io_add_watch(channel,
 525                                 G_IO_IN | G_IO_HUP | G_IO_NVAL | G_IO_ERR,
 526                                 inotify_data, NULL);
 527
 528         g_io_channel_unref(channel);
 529
 530         dirname = g_path_get_dirname(connman_setting_get_string("Localtime"));
 531
 532         wd = inotify_add_watch(fd, dirname, IN_CREATE | IN_DONT_FOLLOW |
 533                                                 IN_CLOSE_WRITE | IN_MOVED_TO);
 534
 535         g_free(dirname);
 536
 537         if (wd < 0)
 538                 return -EIO;
 539
 540         return 0;
 541 }
 542
 543 void __connman_timezone_cleanup(void)
 544 {
 545         DBG("");
 546
 547         if (inotify_watch > 0) {
 548                 g_source_remove(inotify_watch);
 549                 inotify_watch = 0;
 550         }
 551 }