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 <time.h>
  23 #include <string.h>
  24
  25 #include <glib/gprintf.h>
  26 #include <glib-unix.h>
  27 #include <glib/gstdio.h>
  28 #include <polkit/polkit.h>
  29
  30 #include "timedated-gen.h"
  31 #include "timedated.h"
  32
  33 #include "../../util.h"
  34
  35 GPtrArray *timedated_freeable;
  36 Timedate1 *timedated_interf;
  37
  38 GMainLoop *timedated_loop;
  39
  40 guint bus_descriptor;
  41 gboolean dbus_interface_exported; /* reliable because of gdbus operational guarantees */
  42
  43 const gchar *OS_LOCALTIME       = "/etc/localtime";      /* current timezone file */
  44 const gchar *OS_TIMEZONE_PATH   = "/usr/share/zoneinfo"; /* path to system timezone files */
  45
  46 struct timezone_checksum_pair {
  47
  48     gchar *path;
  49     gchar *sum;
  50     gboolean posix;
  51     gboolean right;
  52 };
  53
  54 static struct timezone_checksum_pair tz_table[5000];
  55
  56 /* --- begin method/property/dbus signal code --- */
  57
  58 static gboolean
  59 on_handle_set_time(Timedate1 *hn1_passed_interf,
  60                    GDBusMethodInvocation *invoc,
  61                    const gchar *greet,
  62                    gpointer data) {
  63     return FALSE;
  64 }
  65
  66 static gboolean
  67 on_handle_set_timezone(Timedate1 *hn1_passed_interf,
  68                    GDBusMethodInvocation *invoc,
  69                    const gchar *greet,
  70                    gpointer data) {
  71     return FALSE;
  72 }
  73
  74 static gboolean
  75 on_handle_set_local_rtc(Timedate1 *hn1_passed_interf,
  76                         GDBusMethodInvocation *invoc,
  77                         const gchar *greet,
  78                         gpointer data) {
  79     return FALSE;
  80 }
  81
  82 static gboolean
  83 on_handle_set_ntp(Timedate1 *hn1_passed_interf,
  84                   GDBusMethodInvocation *invoc,
  85                   const gchar *greet,
  86                   gpointer data) {
  87     return FALSE;
  88 }
  89
  90 const gchar *
  91 our_get_timezone() {
  92
  93     GStatBuf *stat_zoneinfo;
  94     gchar *find_cmd, *readlink_path, *ret, *argvp, *hash_to_match;
  95     gint argcp;
  96     GError *err;
  97     struct timezone_checksum_pair tmp;
  98
  99     find_cmd      = (gchar *)    g_malloc0(2048);
 100     stat_zoneinfo = (GStatBuf *) g_malloc0(8192);
 101     err           = (GError *)   g_malloc0(2048);
 102
 103     if(g_stat(OS_LOCALTIME, stat_zoneinfo)) {
 104
 105         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);
 106         ret = NULL;
 107
 108     } else if(g_file_test(OS_LOCALTIME, G_FILE_TEST_IS_SYMLINK)) {
 109
 110         readlink_path = g_file_read_link(OS_LOCALTIME, &err);
 111
 112         gchar *split[2] = { readlink_path, "" };
 113         tmp = parse_timezone_path(split);
 114
 115         ret = tmp.path;
 116
 117         if(readlink_path)
 118             g_free(readlink_path);
 119
 120     } else {
 121
 122         g_printf("%s is not a symlink! attempting to match checksums in %s...\n", OS_LOCALTIME, OS_TIMEZONE_PATH);
 123         hash_to_match = get_file_sha256(OS_LOCALTIME);
 124
 125         ret = lookup_hash(hash_to_match);
 126
 127         if(hash_to_match)
 128             g_free(hash_to_match);
 129     }
 130
 131     return ret;
 132 }
 133
 134 gboolean
 135 our_get_local_rtc() {
 136
 137     gboolean ret = FALSE;
 138
 139     return ret;
 140 }
 141
 142 gboolean
 143 our_get_can_ntp() {
 144
 145     const gboolean ret = FALSE;
 146
 147     return ret;
 148 }
 149
 150 gboolean
 151 our_get_ntp() {
 152
 153     const gboolean ret = FALSE;
 154
 155     return ret;
 156 }
 157
 158 gboolean
 159 our_get_ntpsynchronized() {
 160
 161     const gboolean ret = FALSE;
 162
 163     return ret;
 164 }
 165
 166 guint64
 167 our_get_time_usec() {
 168
 169     guint64 ret = 0;
 170
 171     return ret;
 172 }
 173
 174 guint64
 175 our_get_rtc_time_usec() {
 176
 177     guint64 ret = 0;
 178
 179     return ret;
 180 }
 181
 182 /* --- end method/property/dbus signal code, begin bus/name handlers --- */
 183
 184 static void timedated_on_bus_acquired(GDBusConnection *conn,
 185                                       const gchar *name,
 186                                       gpointer user_data) {
 187
 188     g_printf("got bus/name, exporting %s's interface...\n", name);
 189
 190     timedated_interf = timedate1_skeleton_new();
 191
 192     /* attach function pointers to generated struct's method handlers */
 193     g_signal_connect(timedated_interf, "handle-set-time",     G_CALLBACK(on_handle_set_time),     NULL);
 194     g_signal_connect(timedated_interf, "handle-set-timezone", G_CALLBACK(on_handle_set_timezone), NULL);
 195     g_signal_connect(timedated_interf, "handle-set-local-rtc", G_CALLBACK(on_handle_set_local_rtc), NULL);
 196     g_signal_connect(timedated_interf, "handle-set-ntp",      G_CALLBACK(on_handle_set_ntp),      NULL);
 197
 198     /* set our properties before export */
 199     timedate1_set_timezone(timedated_interf, our_get_timezone());
 200     timedate1_set_local_rtc(timedated_interf, our_get_local_rtc());
 201     timedate1_set_can_ntp(timedated_interf, our_get_can_ntp());
 202     timedate1_set_ntp(timedated_interf, our_get_ntp());
 203     timedate1_set_ntpsynchronized(timedated_interf, our_get_ntpsynchronized());
 204     timedate1_set_time_usec(timedated_interf, our_get_time_usec());
 205     timedate1_set_rtctime_usec(timedated_interf, our_get_rtc_time_usec());
 206
 207     if(!g_dbus_interface_skeleton_export(G_DBUS_INTERFACE_SKELETON(timedated_interf),
 208                                          conn,
 209                                          "/org/freedesktop/timedate1",
 210                                          NULL)) {
 211
 212         g_printf("failed to export %s's interface!\n", name);
 213         timedated_mem_clean();
 214
 215     } else {
 216
 217         dbus_interface_exported = TRUE;
 218         g_printf("exported %s's interface on the system bus...\n", name);
 219     }
 220 }
 221
 222 static void timedated_on_name_acquired(GDBusConnection *conn,
 223                                        const gchar *name,
 224                                        gpointer user_data) {
 225
 226    g_printf("success!\n");
 227 }
 228
 229 static void timedated_on_name_lost(GDBusConnection *conn,
 230                                    const gchar *name,
 231                                    gpointer user_data) {
 232
 233     if(!conn) {
 234
 235         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);
 236         timedated_mem_clean();
 237     }
 238
 239     g_print("lost name %s, exiting...\n", name);
 240
 241     timedated_mem_clean();
 242 }
 243
 244 /* --- end bus/name handlers, begin misc unix functions --- */
 245
 246 /* safe call to clean and then exit
 247  * this stops our GMainLoop safely before letting main() return */
 248 void timedated_mem_clean() {
 249
 250     g_printf("exiting...\n");
 251
 252     if(dbus_interface_exported)
 253         g_dbus_interface_skeleton_unexport(G_DBUS_INTERFACE_SKELETON(timedated_interf));
 254
 255      if(g_main_loop_is_running(timedated_loop))
 256         g_main_loop_quit(timedated_loop);
 257
 258 }
 259
 260 /* wrapper for glib's unix signal handling; called only once if terminating signal is raised against us */
 261 gboolean unix_sig_terminate_handler(gpointer data) {
 262
 263     g_printf("caught SIGINT/HUP/TERM, exiting\n");
 264
 265     timedated_mem_clean();
 266     return G_SOURCE_REMOVE;
 267 }
 268
 269 void set_signal_handlers() {
 270
 271     /* we don't care about its descriptor, we never need to unregister these */
 272     g_unix_signal_add(SIGINT,  unix_sig_terminate_handler, NULL);
 273     g_unix_signal_add(SIGHUP,  unix_sig_terminate_handler, NULL);
 274     g_unix_signal_add(SIGTERM, unix_sig_terminate_handler, NULL);
 275 }
 276
 277 int main() {
 278
 279     set_signal_handlers();
 280
 281     if(!build_lookup_table())
 282         return 1;
 283
 284     timedated_loop = g_main_loop_new(NULL, TRUE);
 285     timedated_freeable = g_ptr_array_new();
 286
 287      bus_descriptor = g_bus_own_name(G_BUS_TYPE_SYSTEM,
 288                                     "org.freedesktop.timedate1",
 289                                     G_BUS_NAME_OWNER_FLAGS_NONE,
 290                                     timedated_on_bus_acquired,
 291                                     timedated_on_name_acquired,
 292                                     timedated_on_name_lost,
 293                                     NULL,
 294                                     NULL);
 295
 296     g_main_loop_run(timedated_loop);
 297     /* runs until single g_main_loop_quit() call is raised inside <interface>_mem_clean() */
 298     g_main_loop_unref(timedated_loop);
 299
 300     /* guaranteed unownable */
 301     g_bus_unown_name(bus_descriptor);
 302
 303     /* at this point no operations can occur with our data, it is safe to free it + its container */
 304     g_ptr_array_free(timedated_freeable, TRUE);
 305
 306     return 0;
 307 }
 308
 309 static struct timezone_checksum_pair parse_timezone_path(gchar **pair) {
 310
 311     gchar *prefix_pattern, *right_prefix_pattern, *posix_prefix_pattern, *lean_path;
 312     GRegex *prefix, *posix, *right;
 313     GError *err = NULL;
 314     struct timezone_checksum_pair ret = { NULL, NULL, FALSE, FALSE };
 315
 316     if(!pair[0])
 317         return ret;
 318
 319     prefix_pattern = (gchar *) g_malloc0(4096);
 320     right_prefix_pattern = (gchar *) g_malloc0(4096);
 321     posix_prefix_pattern = (gchar *) g_malloc0(4096);
 322
 323     g_sprintf(prefix_pattern, "%s/", OS_TIMEZONE_PATH);
 324     g_sprintf(posix_prefix_pattern, "%s/posix/", OS_TIMEZONE_PATH);
 325     g_sprintf(right_prefix_pattern, "%s/right/", OS_TIMEZONE_PATH);
 326
 327     prefix = g_regex_new(prefix_pattern, 0, 0, &err);
 328     posix  = g_regex_new(posix_prefix_pattern, 0, 0, &err);
 329     right  = g_regex_new(right_prefix_pattern, 0, 0, &err);
 330
 331     if(g_regex_match_full(posix, pair[0], -1, 0, G_REGEX_MATCH_NOTEMPTY, NULL, NULL)) {
 332
 333         ret.posix = TRUE;
 334         lean_path = g_regex_replace_literal(posix, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 335
 336     } else if(g_regex_match_full(right, pair[0], -1, 0, G_REGEX_MATCH_NOTEMPTY, NULL, NULL)) {
 337
 338        ret.right = TRUE;
 339        lean_path = g_regex_replace_literal(right, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 340
 341     } else
 342         lean_path = g_regex_replace_literal(prefix, pair[0], -1, 0, "", G_REGEX_MATCH_NOTEMPTY, NULL);
 343
 344     ret.path = lean_path;
 345
 346     ret.sum = g_malloc0(256);
 347     g_strlcpy(ret.sum, pair[1], 66);
 348
 349     g_regex_unref(prefix);
 350     g_regex_unref(right);
 351     g_regex_unref(posix);
 352
 353     return ret;
 354 }
 355
 356 /* TODO need to deconstruct tz_table on exit */
 357 static gboolean build_lookup_table() {
 358
 359         gchar *find_cmd, **map_pairs, *find_output, *path_buf, *sum_buf, **entry_buf;
 360         GError *err;
 361         gboolean ret;
 362         gint i;
 363
 364         i   = 0;
 365         err = NULL;
 366         ret = TRUE;
 367
 368         find_cmd    = (gchar *) g_malloc0(4096);
 369         find_output = (gchar *) g_malloc0(1000000);
 370
 371         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);
 372
 373         if(!g_spawn_command_line_sync(find_cmd, &find_output, NULL, NULL, &err)) {
 374
 375             g_printf("error running `%s`\n", find_cmd);
 376             ret = FALSE;
 377         }
 378
 379         map_pairs = g_strsplit(find_output, "\n", INT_MAX);
 380
 381         while(map_pairs[i] && (entry_buf = g_strsplit(map_pairs[i], "=", INT_MAX))) {
 382
 383             tz_table[i] = parse_timezone_path(entry_buf);
 384
 385             g_strfreev(entry_buf);
 386             i++;
 387         }
 388
 389         g_free(find_output);
 390         g_free(find_cmd);
 391         g_free(map_pairs);
 392
 393         return ret;
 394 }
 395
 396 static gchar *lookup_hash(gchar *hash) {
 397
 398     gint i = 0;
 399
 400     while(tz_table[i].sum)
 401         if(!g_strcmp0(tz_table[i].sum, hash))
 402             return tz_table[i].path;
 403         else
 404             i++;
 405
 406     return NULL;
 407 }