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(relative) {
 105
 106         new_time = (struct timespec *) g_malloc0(sizeof(struct timespec));
 107
 108         cur_time = g_get_real_time();
 109         /* LEFT OFF HERE 9/13 */ return FALSE;
 110     } else if(proposed_time >= 0) {
 111
 112         new_time = (struct timespec *) g_malloc0(sizeof(struct timespec));
 113         new_time->tv_sec = proposed_time;
 114         new_time->tv_nsec = 0;
 115         g_ptr_array_add(timedated_freeable, new_time);
 116
 117         if(!clock_settime(CLOCK_REALTIME, new_time)) {
 118
 119             timedate1_complete_set_time(td1_passed_interf, invoc);
 120             return TRUE;
 121
 122         } else {
 123
 124             g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.Error.ECANCELED", "Failed to set system time for unknown reasons.");
 125             return FALSE;
 126         }
 127     } else {
 128
 129         g_dbus_method_invocation_return_dbus_error(invoc, "org.freedesktop.timedate1.EDOM", "Provided time results in a negative clock value.");
 130         return FALSE;
 131     }
 132 }
 133
 134 static gboolean
 135 on_handle_set_timezone(Timedate1 *td1_passed_interf,
 136                    GDBusMethodInvocation *invoc,
 137                    const gchar *greet,
 138                    gpointer data) {
 139     return FALSE;
 140 }
 141
 142 static gboolean
 143 on_handle_set_local_rtc(Timedate1 *td1_passed_interf,
 144                         GDBusMethodInvocation *invoc,
 145                         const gchar *greet,
 146                         gpointer data) {
 147     return FALSE;
 148 }
 149
 150 static gboolean
 151 on_handle_set_ntp(Timedate1 *td1_passed_interf,
 152                   GDBusMethodInvocation *invoc,
 153                   const gchar *greet,
 154                   gpointer data) {
 155     return FALSE;
 156 }
 157
 158 const gchar *
 159 our_get_timezone() {
 160
 161     GStatBuf *stat_zoneinfo;
 162     gchar *find_cmd, *readlink_path, *ret, *argvp, *hash_to_match;
 163     gint argcp;
 164     GError *err;
 165     struct timezone_checksum_pair tmp;
 166
 167     find_cmd      = (gchar *)    g_malloc0(2048);
 168     stat_zoneinfo = (GStatBuf *) g_malloc0(8192);
 169     err           = (GError *)   g_malloc0(2048);
 170
 171     if(g_stat(OS_LOCALTIME, stat_zoneinfo)) {
 172
 173         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);
 174         ret = NULL;
 175
 176     } else if(g_file_test(OS_LOCALTIME, G_FILE_TEST_IS_SYMLINK)) {
 177
 178         readlink_path = g_file_read_link(OS_LOCALTIME, &err);
 179
 180         gchar *split[2] = { readlink_path, "" };
 181         tmp = parse_timezone_path(split);
 182
 183         ret = tmp.path;
 184
 185         if(readlink_path)
 186             g_free(readlink_path);
 187
 188     } else {
 189
 190         g_printf("%s is not a symlink! attempting to match checksums in %s...\n", OS_LOCALTIME, OS_TIMEZONE_PATH);
 191         hash_to_match = get_file_sha256(OS_LOCALTIME);
 192
 193         ret = lookup_hash(hash_to_match);
 194
 195         if(hash_to_match)
 196             g_free(hash_to_match);
 197     }
 198
 199     return ret;
 200 }
 201
 202 gboolean
 203 our_get_local_rtc() {
 204
 205     gboolean ret = FALSE;
 206
 207     return ret;
 208 }
 209
 210 gboolean
 211 our_get_can_ntp() {
 212
 213     const gboolean ret = FALSE;
 214
 215     return ret;
 216 }
 217
 218 gboolean
 219 our_get_ntp() {
 220
 221     const gboolean ret = FALSE;
 222
 223     return ret;
 224 }
 225
 226 gboolean
 227 our_get_ntpsynchronized() {
 228
 229     const gboolean ret = FALSE;
 230
 231     return ret;
 232 }
 233
 234 guint64
 235 our_get_time_usec() {
 236
 237     guint64 ret = 0;
 238
 239     return ret;
 240 }
 241
 242 guint64
 243 our_get_rtc_time_usec() {
 244
 245     guint64 ret = 0;
 246
 247     return ret;
 248 }
 249
 250 /* --- end method/property/dbus signal code, begin bus/name handlers --- */
 251
 252 static void timedated_on_bus_acquired(GDBusConnection *conn,
 253                                       const gchar *name,
 254                                       gpointer user_data) {
 255
 256     g_printf("got bus/name, exporting %s's interface...\n", name);
 257
 258     timedated_interf = timedate1_skeleton_new();
 259
 260     /* attach function pointers to generated struct's method handlers */
 261     g_signal_connect(timedated_interf, "handle-set-time",     G_CALLBACK(on_handle_set_time),     NULL);
 262     g_signal_connect(timedated_interf, "handle-set-timezone", G_CALLBACK(on_handle_set_timezone), NULL);
 263     g_signal_connect(timedated_interf, "handle-set-local-rtc", G_CALLBACK(on_handle_set_local_rtc), NULL);
 264     g_signal_connect(timedated_interf, "handle-set-ntp",      G_CALLBACK(on_handle_set_ntp),      NULL);
 265
 266     /* set our properties before export */
 267     timedate1_set_timezone(timedated_interf, our_get_timezone());
 268     timedate1_set_local_rtc(timedated_interf, our_get_local_rtc());
 269     timedate1_set_can_ntp(timedated_interf, our_get_can_ntp());
 270     timedate1_set_ntp(timedated_interf, our_get_ntp());
 271     timedate1_set_ntpsynchronized(timedated_interf, our_get_ntpsynchronized());
 272     timedate1_set_time_usec(timedated_interf, our_get_time_usec());
 273     timedate1_set_rtctime_usec(timedated_interf, our_get_rtc_time_usec());
 274
 275     if(!g_dbus_interface_skeleton_export(G_DBUS_INTERFACE_SKELETON(timedated_interf),
 276                                          conn,
 277                                          "/org/freedesktop/timedate1",
 278                                          NULL)) {
 279
 280         g_printf("failed to export %s's interface!\n", name);
 281         timedated_mem_clean();
 282
 283     } else {
 284
 285         dbus_interface_exported = TRUE;
 286         g_printf("exported %s's interface on the system bus...\n", name);
 287     }
 288 }
 289
 290 static void timedated_on_name_acquired(GDBusConnection *conn,
 291                                        const gchar *name,
 292                                        gpointer user_data) {
 293
 294    g_printf("success!\n");
 295 }
 296
 297 static void timedated_on_name_lost(GDBusConnection *conn,
 298                                    const gchar *name,
 299                                    gpointer user_data) {
 300
 301     if(!conn) {
 302
 303         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);
 304         timedated_mem_clean();
 305     }
 306
 307     g_print("lost name %s, exiting...\n", name);
 308
 309     timedated_mem_clean();
 310 }
 311
 312 /* --- end bus/name handlers, begin misc unix functions --- */
 313
 314 /* safe call to clean and then exit
 315  * this stops our GMainLoop safely before letting main() return */
 316 void timedated_mem_clean() {
 317
 318     g_printf("exiting...\n");
 319
 320     if(dbus_interface_exported)
 321         g_dbus_interface_skeleton_unexport(G_DBUS_INTERFACE_SKELETON(timedated_interf));
 322
 323      if(g_main_loop_is_running(timedated_loop))
 324         g_main_loop_quit(timedated_loop);
 325
 326 }
 327
 328 /* wrapper for glib's unix signal handling; called only once if terminating signal is raised against us */
 329 gboolean unix_sig_terminate_handler(gpointer data) {
 330
 331     g_printf("caught SIGINT/HUP/TERM, exiting\n");
 332
 333     timedated_mem_clean();
 334     return G_SOURCE_REMOVE;
 335 }
 336
 337 void set_signal_handlers() {
 338
 339     /* we don't care about its descriptor, we never need to unregister these */
 340     g_unix_signal_add(SIGINT,  unix_sig_terminate_handler, NULL);
 341     g_unix_signal_add(SIGHUP,  unix_sig_terminate_handler, NULL);
 342     g_unix_signal_add(SIGTERM, unix_sig_terminate_handler, NULL);
 343 }
 344
 345 int main() {
 346
 347     set_signal_handlers();
 348
 349     if(!build_lookup_table())
 350         return 1;
 351
 352     timedated_loop = g_main_loop_new(NULL, TRUE);
 353     timedated_freeable = g_ptr_array_new();
 354
 355      bus_descriptor = g_bus_own_name(G_BUS_TYPE_SYSTEM,
 356                                     "org.freedesktop.timedate1",
 357                                     G_BUS_NAME_OWNER_FLAGS_NONE,
 358                                     timedated_on_bus_acquired,
 359                                     timedated_on_name_acquired,
 360                                     timedated_on_name_lost,
 361                                     NULL,
 362                                     NULL);
 363
 364     g_main_loop_run(timedated_loop);
 365     /* runs until single g_main_loop_quit() call is raised inside <interface>_mem_clean() */
 366     g_main_loop_unref(timedated_loop);
 367
 368     /* guaranteed unownable */
 369     g_bus_unown_name(bus_descriptor);
 370
 371     /* at this point no operations can occur with our data, it is safe to free it + its container */
 372     g_ptr_array_free(timedated_freeable, TRUE);
 373
 374     return 0;
 375 }
 376
 377 static struct timezone_checksum_pair parse_timezone_path(gchar **pair) {
 378
 379     gchar *prefix_pattern, *right_prefix_pattern, *posix_prefix_pattern, *lean_path;
 380     GRegex *prefix, *posix, *right;
 381     GError *err = NULL;
 382     struct timezone_checksum_pair ret = { NULL, NULL, FALSE, FALSE };
 383
 384     if(!pair[0])
 385         return ret;
 386
 387     prefix_pattern = (gchar *) g_malloc0(4096);
 388     right_prefix_pattern = (gchar *) g_malloc0(4096);
 389     posix_prefix_pattern = (gchar *) g_malloc0(4096);
 390
 391     g_sprintf(prefix_pattern, "%s/", OS_TIMEZONE_PATH);
 392     g_sprintf(posix_prefix_pattern, "%s/posix/", OS_TIMEZONE_PATH);
 393     g_sprintf(right_prefix_pattern, "%s/right/", OS_TIMEZONE_PATH);
 394
 395     prefix = g_regex_new(prefix_pattern, 0, 0, &err);
 396     posix  = g_regex_new(posix_prefix_pattern, 0, 0, &err);
 397     right  = g_regex_new(right_prefix_pattern, 0, 0, &err);
 398
 399     if(g_regex_match_full(posix, pair[0], -1, 0, G_REGEX_MATCH_NOTEMPTY, NULL, NULL)) {
 400
 401         ret.posix = TRUE;
 402         lean_path = g_regex_replace_literal(posix, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 403
 404     } else if(g_regex_match_full(right, pair[0], -1, 0, G_REGEX_MATCH_NOTEMPTY, NULL, NULL)) {
 405
 406        ret.right = TRUE;
 407        lean_path = g_regex_replace_literal(right, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 408
 409     } else
 410         lean_path = g_regex_replace_literal(prefix, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 411
 412     ret.path = lean_path;
 413
 414     ret.sum = g_malloc0(256);
 415     g_strlcpy(ret.sum, pair[1], 66);
 416
 417     g_regex_unref(prefix);
 418     g_regex_unref(right);
 419     g_regex_unref(posix);
 420
 421     return ret;
 422 }
 423
 424 /* TODO need to deconstruct tz_table on exit */
 425 static gboolean build_lookup_table() {
 426
 427         gchar *find_cmd, **map_pairs, *find_output, *path_buf, *sum_buf, **entry_buf;
 428         GError *err;
 429         gboolean ret;
 430         gint i;
 431
 432         i   = 0;
 433         err = NULL;
 434         ret = TRUE;
 435
 436         find_cmd    = (gchar *) g_malloc0(4096);
 437         find_output = (gchar *) g_malloc0(1000000);
 438
 439         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);
 440
 441         if(!g_spawn_command_line_sync(find_cmd, &find_output, NULL, NULL, &err)) {
 442
 443             g_printf("error running `%s`\n", find_cmd);
 444             ret = FALSE;
 445         }
 446
 447         map_pairs = g_strsplit(find_output, "\n", INT_MAX);
 448
 449         while(map_pairs[i] && (entry_buf = g_strsplit(map_pairs[i], "=", INT_MAX))) {
 450
 451             tz_table[i] = parse_timezone_path(entry_buf);
 452
 453             g_strfreev(entry_buf);
 454             i++;
 455         }
 456
 457         g_free(find_output);
 458         g_free(find_cmd);
 459         g_free(map_pairs);
 460
 461         return ret;
 462 }
 463
 464 static gchar *lookup_hash(gchar *hash) {
 465
 466     gint i = 0;
 467
 468     while(tz_table[i].sum)
 469         if(!g_strcmp0(tz_table[i].sum, hash))
 470             return tz_table[i].path;
 471         else
 472             i++;
 473
 474     return NULL;
 475 }