src/interfaces/timedated/timedated.c

   1 /*
   2  * Copyright (c) 2014 Ian Sutton <ian@kremlin.cc>
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <unistd.h>
  18 #include <limits.h>
  19 #include <signal.h>
  20
  21 #include <sys/types.h>
  22 #include <sys/time.h>
  23 #include <time.h>
  24 #include <string.h>
  25
  26 #include <glib/gprintf.h>
  27 #include <glib-unix.h>
  28 #include <glib/gstdio.h>
  29 #include <polkit/polkit.h>
  30
  31 #include "timedated-gen.h"
  32 #include "timedated.h"
  33
  34 #include "../../util.h"
  35
  36 GPtrArray *timedated_freeable;
  37 Timedate1 *timedated_interf;
  38
  39 GMainLoop *timedated_loop;
  40
  41 guint bus_descriptor;
  42 gboolean dbus_interface_exported; /* reliable because of gdbus operational guarantees */
  43
  44 const gchar *OS_LOCALTIME       = "/etc/localtime";      /* current timezone file */
  45 const gchar *OS_TIMEZONE_PATH   = "/usr/share/zoneinfo"; /* path to system timezone files */
  46
  47 struct timezone_checksum_pair {
  48
  49     gchar *path;
  50     gchar *sum;
  51     gboolean posix;
  52     gboolean right;
  53 };
  54
  55 static struct timezone_checksum_pair tz_table[5000];
  56
  57 /* --- begin method/property/dbus signal code --- */
  58
  59 static gboolean
  60 on_handle_set_time(Timedate1 *td1_passed_interf,
  61                    GDBusMethodInvocation *invoc,
  62                    const gchar *greet,
  63                    gpointer data) {
  64
  65     GVariant *params;
  66     gint64 proposed_time, cur_time;
  67     const gchar *bus_name;
  68     gboolean policykit_auth;
  69     check_auth_result is_authed;
  70     gboolean relative; /* relative if passed time_t is meant to be added to current time */
  71     struct timespec *new_time;
  72
  73     params = g_dbus_method_invocation_get_parameters(invoc);
  74     g_variant_get(params, "(xbb)", &proposed_time, &relative, &policykit_auth);
  75     bus_name = g_dbus_method_invocation_get_sender(invoc);
  76
  77     is_authed = polkit_try_auth(bus_name, "org.freedesktop.timedate1.set-time", policykit_auth);
  78
  79     switch(is_authed) {
  80
  81         case AUTHORIZED_NATIVELY:
  82         case AUTHORIZED_BY_PROMPT:
  83             break;
  84
  85         case UNAUTHORIZED_NATIVELY:
  86         case UNAUTHORIZED_FAILED_PROMPT:
  87             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.EACCES", "Insufficient permissions to set system time.");
  88             return FALSE;
  89
  90         case ERROR_BADBUS:
  91             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.EFAULT", "Provided bus name is invalid.");
  92             return FALSE;
  93
  94         case ERROR_BADACTION:
  95             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.EFAULT", "Provided action ID is invalid.");
  96             return FALSE;
  97
  98         case ERROR_GENERIC:
  99         default:
 100             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.ECANCELED", "Failed to set system time for unknown reasons.");
 101             return FALSE;
 102     }
 103
 104     if(!proposed_time) {
 105
 106         timedate1_complete_set_time(td1_passed_interf, invoc);
 107         return TRUE;
 108
 109     } else if(relative) {
 110
 111         cur_time = g_get_real_time();
 112
 113         if(proposed_time < 0 && cur_time + proposed_time > cur_time) {
 114
 115             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.EINVAL", "Resultant time out of bounds.");
 116             return FALSE;
 117
 118         } else if(proposed_time > 0 && cur_time + proposed_time < cur_time) {
 119
 120             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.EINVAL", "Resultant time out of bounds.");
 121             return FALSE;
 122         }
 123
 124         new_time = mktimespec(proposed_time);
 125
 126         if(!clock_settime(CLOCK_REALTIME, new_time)) {
 127
 128             timedate1_complete_set_time(td1_passed_interf, invoc);
 129             return TRUE;
 130
 131         } else {
 132
 133             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.ECANCELED", "Failed to set system time for unknown reasons.");
 134             return FALSE;
 135         }
 136
 137     } else if(proposed_time > 0) {
 138
 139
 140         new_time = mktimespec(proposed_time);
 141
 142         if(!clock_settime(CLOCK_REALTIME, new_time)) {
 143
 144             timedate1_complete_set_time(td1_passed_interf, invoc);
 145             return TRUE;
 146
 147         } else {
 148
 149             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.ECANCELED", "Failed to set system time for unknown reasons.");
 150             return FALSE;
 151         }
 152
 153     } else {
 154
 155         g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.EINVAL", "Resultant time out of bounds.");
 156         return FALSE;
 157     }
 158 }
 159
 160 static gboolean
 161 on_handle_set_timezone(Timedate1 *td1_passed_interf,
 162                    GDBusMethodInvocation *invoc,
 163                    const gchar *greet,
 164                    gpointer data) {
 165     return FALSE;
 166 }
 167
 168 static gboolean
 169 on_handle_set_local_rtc(Timedate1 *td1_passed_interf,
 170                         GDBusMethodInvocation *invoc,
 171                         const gchar *greet,
 172                         gpointer data) {
 173     return FALSE;
 174 }
 175
 176 static gboolean
 177 on_handle_set_ntp(Timedate1 *td1_passed_interf,
 178                   GDBusMethodInvocation *invoc,
 179                   const gchar *greet,
 180                   gpointer data) {
 181     return FALSE;
 182 }
 183
 184 const gchar *
 185 our_get_timezone() {
 186
 187     GStatBuf *stat_zoneinfo;
 188     gchar *find_cmd, *readlink_path, *ret, *argvp, *hash_to_match;
 189     gint argcp;
 190     GError *err;
 191     struct timezone_checksum_pair tmp;
 192
 193     find_cmd      = (gchar *)    g_malloc0(2048);
 194     stat_zoneinfo = (GStatBuf *) g_malloc0(8192);
 195     err           = (GError *)   g_malloc0(2048);
 196
 197     if(g_stat(OS_LOCALTIME, stat_zoneinfo)) {
 198
 199         g_printf("could not read from %s! please symlink or copy a timezone file from %s to %s!\n", OS_LOCALTIME, OS_TIMEZONE_PATH, OS_LOCALTIME);
 200         ret = NULL;
 201
 202     } else if(g_file_test(OS_LOCALTIME, G_FILE_TEST_IS_SYMLINK)) {
 203
 204         readlink_path = g_file_read_link(OS_LOCALTIME, &err);
 205
 206         gchar *split[2] = { readlink_path, "" };
 207         tmp = parse_timezone_path(split);
 208
 209         ret = tmp.path;
 210
 211         if(readlink_path)
 212             g_free(readlink_path);
 213
 214     } else {
 215
 216         g_printf("%s is not a symlink! attempting to match checksums in %s...\n", OS_LOCALTIME, OS_TIMEZONE_PATH);
 217         hash_to_match = get_file_sha256(OS_LOCALTIME);
 218
 219         /* ret = lookup_hash(hash_to_match); */
 220         return FALSE; /* TODO fix me for real */
 221
 222         if(hash_to_match)
 223             g_free(hash_to_match);
 224     }
 225
 226     return ret;
 227 }
 228
 229 gboolean
 230 our_get_local_rtc() {
 231
 232     gboolean ret = FALSE;
 233
 234     return ret;
 235 }
 236
 237 gboolean
 238 our_get_can_ntp() {
 239
 240     const gboolean ret = FALSE;
 241
 242     return ret;
 243 }
 244
 245 gboolean
 246 our_get_ntp() {
 247
 248     const gboolean ret = FALSE;
 249
 250     return ret;
 251 }
 252
 253 gboolean
 254 our_get_ntpsynchronized() {
 255
 256     const gboolean ret = FALSE;
 257
 258     return ret;
 259 }
 260
 261 guint64
 262 our_get_time_usec() {
 263
 264     guint64 ret = 0;
 265
 266     return ret;
 267 }
 268
 269 guint64
 270 our_get_rtc_time_usec() {
 271
 272     guint64 ret = 0;
 273
 274     return ret;
 275 }
 276
 277 /* --- end method/property/dbus signal code, begin bus/name handlers --- */
 278
 279 static void timedated_on_bus_acquired(GDBusConnection *conn,
 280                                       const gchar *name,
 281                                       gpointer user_data) {
 282
 283     g_printf("got bus/name, exporting %s's interface...\n", name);
 284
 285     timedated_interf = timedate1_skeleton_new();
 286
 287     /* attach function pointers to generated struct's method handlers */
 288     g_signal_connect(timedated_interf, "handle-set-time",     G_CALLBACK(on_handle_set_time),     NULL);
 289     g_signal_connect(timedated_interf, "handle-set-timezone", G_CALLBACK(on_handle_set_timezone), NULL);
 290     g_signal_connect(timedated_interf, "handle-set-local-rtc", G_CALLBACK(on_handle_set_local_rtc), NULL);
 291     g_signal_connect(timedated_interf, "handle-set-ntp",      G_CALLBACK(on_handle_set_ntp),      NULL);
 292
 293     /* set our properties before export */
 294     timedate1_set_timezone(timedated_interf, our_get_timezone());
 295     timedate1_set_local_rtc(timedated_interf, our_get_local_rtc());
 296     timedate1_set_can_ntp(timedated_interf, our_get_can_ntp());
 297     timedate1_set_ntp(timedated_interf, our_get_ntp());
 298     timedate1_set_ntpsynchronized(timedated_interf, our_get_ntpsynchronized());
 299     timedate1_set_time_usec(timedated_interf, our_get_time_usec());
 300     timedate1_set_rtctime_usec(timedated_interf, our_get_rtc_time_usec());
 301
 302     if(!g_dbus_interface_skeleton_export(G_DBUS_INTERFACE_SKELETON(timedated_interf),
 303                                          conn,
 304                                          "/org/freedesktop/timedate1",
 305                                          NULL)) {
 306
 307         g_printf("failed to export %s's interface!\n", name);
 308         timedated_mem_clean();
 309
 310     } else {
 311
 312         dbus_interface_exported = TRUE;
 313         g_printf("exported %s's interface on the system bus...\n", name);
 314     }
 315 }
 316
 317 static void timedated_on_name_acquired(GDBusConnection *conn,
 318                                        const gchar *name,
 319                                        gpointer user_data) {
 320
 321    g_printf("success!\n");
 322 }
 323
 324 static void timedated_on_name_lost(GDBusConnection *conn,
 325                                    const gchar *name,
 326                                    gpointer user_data) {
 327
 328     if(!conn) {
 329
 330         g_printf("failed to connect to the system bus while trying to acquire name '%s': either dbus-daemon isn't running or we don't have permission to push names and/or their interfaces to it.\n", name);
 331         timedated_mem_clean();
 332     }
 333
 334     g_print("lost name %s, exiting...\n", name);
 335
 336     timedated_mem_clean();
 337 }
 338
 339 /* --- end bus/name handlers, begin misc unix functions --- */
 340
 341 /* safe call to clean and then exit
 342  * this stops our GMainLoop safely before letting main() return */
 343 void timedated_mem_clean() {
 344
 345     g_printf("exiting...\n");
 346
 347     if(dbus_interface_exported)
 348         g_dbus_interface_skeleton_unexport(G_DBUS_INTERFACE_SKELETON(timedated_interf));
 349
 350      if(g_main_loop_is_running(timedated_loop))
 351         g_main_loop_quit(timedated_loop);
 352
 353 }
 354
 355 /* wrapper for glib's unix signal handling; called only once if terminating signal is raised against us */
 356 gboolean unix_sig_terminate_handler(gpointer data) {
 357
 358     g_printf("caught SIGINT/HUP/TERM, exiting\n");
 359
 360     timedated_mem_clean();
 361     return G_SOURCE_REMOVE;
 362 }
 363
 364 void set_signal_handlers() {
 365
 366     /* we don't care about its descriptor, we never need to unregister these */
 367     g_unix_signal_add(SIGINT,  unix_sig_terminate_handler, NULL);
 368     g_unix_signal_add(SIGHUP,  unix_sig_terminate_handler, NULL);
 369     g_unix_signal_add(SIGTERM, unix_sig_terminate_handler, NULL);
 370 }
 371
 372 int main() {
 373
 374     set_signal_handlers();
 375
 376     /*if(!build_lookup_table())
 377         return 1; */
 378
 379     timedated_loop = g_main_loop_new(NULL, TRUE);
 380     timedated_freeable = g_ptr_array_new();
 381
 382      bus_descriptor = g_bus_own_name(G_BUS_TYPE_SYSTEM,
 383                                     "org.freedesktop.timedate1",
 384                                     G_BUS_NAME_OWNER_FLAGS_NONE,
 385                                     timedated_on_bus_acquired,
 386                                     timedated_on_name_acquired,
 387                                     timedated_on_name_lost,
 388                                     NULL,
 389                                     NULL);
 390
 391     g_main_loop_run(timedated_loop);
 392     /* runs until single g_main_loop_quit() call is raised inside <interface>_mem_clean() */
 393     g_main_loop_unref(timedated_loop);
 394
 395     /* guaranteed unownable */
 396     g_bus_unown_name(bus_descriptor);
 397
 398     /* at this point no operations can occur with our data, it is safe to free it + its container */
 399     g_ptr_array_free(timedated_freeable, TRUE);
 400
 401     return 0;
 402 }
 403
 404 static struct timezone_checksum_pair parse_timezone_path(gchar **pair) {
 405
 406     gchar *prefix_pattern, *right_prefix_pattern, *posix_prefix_pattern, *lean_path;
 407     GRegex *prefix, *posix, *right;
 408     GError *err = NULL;
 409     struct timezone_checksum_pair ret = { NULL, NULL, FALSE, FALSE };
 410
 411     if(!pair[0])
 412         return ret;
 413
 414     prefix_pattern = (gchar *) g_malloc0(4096);
 415     right_prefix_pattern = (gchar *) g_malloc0(4096);
 416     posix_prefix_pattern = (gchar *) g_malloc0(4096);
 417
 418     g_sprintf(prefix_pattern, "%s/", OS_TIMEZONE_PATH);
 419     g_sprintf(posix_prefix_pattern, "%s/posix/", OS_TIMEZONE_PATH);
 420     g_sprintf(right_prefix_pattern, "%s/right/", OS_TIMEZONE_PATH);
 421
 422     prefix = g_regex_new(prefix_pattern, 0, 0, &err);
 423     posix  = g_regex_new(posix_prefix_pattern, 0, 0, &err);
 424     right  = g_regex_new(right_prefix_pattern, 0, 0, &err);
 425
 426     if(g_regex_match_full(posix, pair[0], -1, 0, G_REGEX_MATCH_NOTEMPTY, NULL, NULL)) {
 427
 428         ret.posix = TRUE;
 429         lean_path = g_regex_replace_literal(posix, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 430
 431     } else if(g_regex_match_full(right, pair[0], -1, 0, G_REGEX_MATCH_NOTEMPTY, NULL, NULL)) {
 432
 433        ret.right = TRUE;
 434        lean_path = g_regex_replace_literal(right, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 435
 436     } else
 437         lean_path = g_regex_replace_literal(prefix, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 438
 439     ret.path = lean_path;
 440
 441     ret.sum = g_malloc0(256);
 442     g_strlcpy(ret.sum, pair[1], 66);
 443
 444     g_regex_unref(prefix);
 445     g_regex_unref(right);
 446     g_regex_unref(posix);
 447
 448     return ret;
 449 }
 450
 451 /* TODO need to deconstruct tz_table on exit
 452 static gboolean build_lookup_table() {
 453
 454         gchar *find_cmd, **map_pairs, *find_output, *path_buf, *sum_buf, **entry_buf;
 455         GError *err;
 456         gboolean ret;
 457         gint i;
 458
 459         i   = 0;
 460         err = NULL;
 461         ret = TRUE;
 462
 463         find_cmd    = (gchar *) g_malloc0(4096);
 464         find_output = (gchar *) g_malloc0(1000000);
 465
 466         g_sprintf(find_cmd, "/bin/sh -c \"find %s -type f -exec cksum -a sha256 {} \\; | sed -E 's/SHA256 \\(//g' | sed -E 's/\\) = /=/g'\"", OS_TIMEZONE_PATH);
 467
 468         if(!g_spawn_command_line_sync(find_cmd, &find_output, NULL, NULL, &err)) {
 469
 470             g_printf("error running `%s`\n", find_cmd);
 471             ret = FALSE;
 472         }
 473
 474         map_pairs = g_strsplit(find_output, "\n", INT_MAX);
 475
 476         while(map_pairs[i] && (entry_buf = g_strsplit(map_pairs[i], "=", INT_MAX))) {
 477
 478             tz_table[i] = parse_timezone_path(entry_buf);
 479
 480             g_strfreev(entry_buf);
 481             i++;
 482         }
 483
 484         g_free(find_output);
 485         g_free(find_cmd);
 486         g_free(map_pairs);
 487
 488         return ret;
 489 }
 490
 491 static gchar *lookup_hash(gchar *hash) {
 492
 493     gint i = 0;
 494
 495     while(tz_table[i].sum)
 496         if(!g_strcmp0(tz_table[i].sum, hash))
 497             return tz_table[i].path;
 498         else
 499             i++;
 500
 501     return NULL;
 502 }*/
 503
 504 /* takes number of microseconds since epoch and returns a
 505  * ptr to a timespec suitable to be passed to clock_settime(3)
 506  */
 507 static struct timespec* mktimespec(gint64 us) {
 508
 509     long nanoseconds;
 510     time_t seconds;
 511
 512     gint64 div_buf_remainder, div_buf_s, div_buf_ns;
 513     struct timespec *ret;
 514
 515     div_buf_s         = (us / 1000000); /* us / 10^6 = s */
 516     div_buf_remainder = (us % 1000000); /* fraction of second lost from prev. line */
 517     div_buf_ns        = div_buf_remainder * 1000; /* us * 10^3 = ns */
 518
 519     seconds     = (time_t) div_buf_s; /* porting note: most systems use 32 bit time, adjust accordingly */
 520     nanoseconds = (long)   div_buf_ns;
 521
 522     ret = (struct timespec *) calloc(1, sizeof(struct timespec));
 523
 524     ret->tv_sec  = seconds;
 525     ret->tv_nsec = nanoseconds;
 526
 527     g_ptr_array_add(timedated_freeable, ret);
 528
 529     return ret;
 530 }