src/odhcp6c.c

   1 /**
   2  * Copyright (C) 2012-2014 Steven Barth <steven@midlink.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License v2 as published by
   6  * the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #include <time.h>
  16 #include <errno.h>
  17 #include <fcntl.h>
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <stddef.h>
  21 #include <unistd.h>
  22 #include <syslog.h>
  23 #include <signal.h>
  24 #include <string.h>
  25 #include <stdbool.h>
  26
  27 #include <net/if.h>
  28 #include <sys/wait.h>
  29 #include <sys/syscall.h>
  30 #include <arpa/inet.h>
  31
  32 #include "odhcp6c.h"
  33 #include "ra.h"
  34
  35 #ifdef EXT_BFD_PING
  36 #include "bfd.h"
  37 #endif
  38
  39
  40 static void sighandler(int signal);
  41 static int usage(void);
  42
  43 static uint8_t *state_data[_STATE_MAX] = {NULL};
  44 static size_t state_len[_STATE_MAX] = {0};
  45
  46 static volatile bool signal_io = false;
  47 static volatile bool signal_usr1 = false;
  48 static volatile bool signal_usr2 = false;
  49 static volatile bool signal_term = false;
  50
  51 static int urandom_fd = -1, allow_slaac_only = 0;
  52 static bool bound = false, release = true;
  53 static time_t last_update = 0;
  54
  55 int main(_unused int argc, char* const argv[])
  56 {
  57         // Allocate ressources
  58         const char *pidfile = NULL;
  59         const char *script = "/usr/sbin/odhcp6c-update";
  60         ssize_t l;
  61         uint8_t buf[134];
  62         char *optpos;
  63         uint16_t opttype;
  64         uint16_t optlen;
  65         enum odhcp6c_ia_mode ia_na_mode = IA_MODE_TRY;
  66         enum odhcp6c_ia_mode ia_pd_mode = IA_MODE_NONE;
  67         int ia_pd_iaid_index = 0;
  68         static struct in6_addr ifid = IN6ADDR_ANY_INIT;
  69         int sol_timeout = DHCPV6_SOL_MAX_RT;
  70
  71 #ifdef EXT_BFD_PING
  72         int bfd_interval = 0, bfd_loss = 3;
  73 #endif
  74
  75         bool help = false, daemonize = false;
  76         int logopt = LOG_PID;
  77         int c;
  78         unsigned int client_options = DHCPV6_CLIENT_FQDN | DHCPV6_ACCEPT_RECONFIGURE;
  79
  80         while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:s:kt:hedp:fa")) != -1) {
  81                 switch (c) {
  82                 case 'S':
  83                         allow_slaac_only = (optarg) ? atoi(optarg) : -1;
  84                         break;
  85
  86                 case 'N':
  87                         if (!strcmp(optarg, "force")) {
  88                                 ia_na_mode = IA_MODE_FORCE;
  89                                 allow_slaac_only = -1;
  90                         } else if (!strcmp(optarg, "none")) {
  91                                 ia_na_mode = IA_MODE_NONE;
  92                         } else if (!strcmp(optarg, "try")) {
  93                                 ia_na_mode = IA_MODE_TRY;
  94                         } else{
  95                                 help = true;
  96                         }
  97                         break;
  98
  99                 case 'V':
 100                         l = script_unhexlify(buf, sizeof(buf), optarg);
 101                         if (!l)
 102                                 help=true;
 103
 104                         odhcp6c_add_state(STATE_VENDORCLASS, buf, l);
 105
 106                         break;
 107                 case 'P':
 108                         if (ia_pd_mode == IA_MODE_NONE)
 109                                 ia_pd_mode = IA_MODE_TRY;
 110
 111                         if (allow_slaac_only >= 0 && allow_slaac_only < 10)
 112                                 allow_slaac_only = 10;
 113
 114                         char *iaid_begin;
 115                         int iaid_len = 0;
 116
 117                         int prefix_length = strtoul(optarg, &iaid_begin, 10);
 118
 119                         if (*iaid_begin != '\0' && *iaid_begin != ',' && *iaid_begin != ':') {
 120                                 syslog(LOG_ERR, "invalid argument: '%s'", optarg);
 121                                 return 1;
 122                         }
 123
 124                         struct odhcp6c_request_prefix prefix = { 0, prefix_length };
 125
 126                         if (*iaid_begin == ',' && (iaid_len = strlen(iaid_begin)) > 1)
 127                                 memcpy(&prefix.iaid, iaid_begin + 1, iaid_len > 4 ? 4 : iaid_len);
 128                         else if (*iaid_begin == ':')
 129                                 prefix.iaid = htonl((uint32_t)strtoul(&iaid_begin[1], NULL, 16));
 130                         else
 131                                 prefix.iaid = htonl(++ia_pd_iaid_index);
 132
 133                         odhcp6c_add_state(STATE_IA_PD_INIT, &prefix, sizeof(prefix));
 134
 135                         break;
 136
 137                 case 'F':
 138                         allow_slaac_only = -1;
 139                         ia_pd_mode = IA_MODE_FORCE;
 140                         break;
 141
 142 #ifdef EXT_BFD_PING
 143                 case 'B':
 144                         bfd_interval = atoi(optarg);
 145                         break;
 146 #endif
 147
 148                 case 'c':
 149                         l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
 150                         if (l > 0) {
 151                                 buf[0] = 0;
 152                                 buf[1] = DHCPV6_OPT_CLIENTID;
 153                                 buf[2] = 0;
 154                                 buf[3] = l;
 155                                 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
 156                         } else {
 157                                 help = true;
 158                         }
 159                         break;
 160
 161                 case 'i':
 162                         if (inet_pton(AF_INET6, optarg, &ifid) != 1)
 163                                 help = true;
 164                         break;
 165
 166                 case 'r':
 167                         optpos = optarg;
 168                         while (optpos[0]) {
 169                                 opttype = htons(strtoul(optarg, &optpos, 10));
 170                                 if (optpos == optarg)
 171                                         break;
 172                                 else if (optpos[0])
 173                                         optarg = &optpos[1];
 174                                 odhcp6c_add_state(STATE_ORO, &opttype, 2);
 175                         }
 176                         break;
 177
 178                 case 'R':
 179                         client_options |= DHCPV6_STRICT_OPTIONS;
 180                         break;
 181
 182                 case 'u':
 183                         optlen = htons(strlen(optarg));
 184                         odhcp6c_add_state(STATE_USERCLASS, &optlen, 2);
 185                         odhcp6c_add_state(STATE_USERCLASS, optarg, strlen(optarg));
 186                         break;
 187
 188                 case 's':
 189                         script = optarg;
 190                         break;
 191
 192                 case 'k':
 193                         release = false;
 194                         break;
 195
 196                 case 't':
 197                         sol_timeout = atoi(optarg);
 198                         break;
 199
 200                 case 'e':
 201                         logopt |= LOG_PERROR;
 202                         break;
 203
 204                 case 'd':
 205                         daemonize = true;
 206                         break;
 207
 208                 case 'p':
 209                         pidfile = optarg;
 210                         break;
 211
 212                 case 'f':
 213                         client_options &= ~DHCPV6_CLIENT_FQDN;
 214                         break;
 215
 216                 case 'a':
 217                         client_options &= ~DHCPV6_ACCEPT_RECONFIGURE;
 218                         break;
 219
 220                 default:
 221                         help = true;
 222                         break;
 223                 }
 224         }
 225
 226         openlog("odhcp6c", logopt, LOG_DAEMON);
 227         const char *ifname = argv[optind];
 228
 229         if (help || !ifname)
 230                 return usage();
 231
 232         signal(SIGIO, sighandler);
 233         signal(SIGHUP, sighandler);
 234         signal(SIGINT, sighandler);
 235         signal(SIGCHLD, sighandler);
 236         signal(SIGTERM, sighandler);
 237         signal(SIGUSR1, sighandler);
 238         signal(SIGUSR2, sighandler);
 239
 240         if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
 241                         init_dhcpv6(ifname, client_options, sol_timeout) ||
 242                         ra_init(ifname, &ifid) || script_init(script, ifname)) {
 243                 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
 244                 return 3;
 245         }
 246
 247         if (daemonize) {
 248                 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
 249                 if (daemon(0, 0)) {
 250                         syslog(LOG_ERR, "Failed to daemonize: %s",
 251                                         strerror(errno));
 252                         return 4;
 253                 }
 254
 255                 char pidbuf[128];
 256                 if (!pidfile) {
 257                         snprintf(pidbuf, sizeof(pidbuf),
 258                                         "/var/run/odhcp6c.%s.pid", ifname);
 259                         pidfile = pidbuf;
 260                 }
 261
 262                 int fd = open(pidfile, O_WRONLY | O_CREAT);
 263                 if (fd >= 0) {
 264                         char buf[8];
 265                         int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
 266                         write(fd, buf, len);
 267                         close(fd);
 268                 }
 269         }
 270
 271         script_call("started");
 272
 273         while (!signal_term) { // Main logic
 274                 odhcp6c_clear_state(STATE_SERVER_ID);
 275                 odhcp6c_clear_state(STATE_IA_NA);
 276                 odhcp6c_clear_state(STATE_IA_PD);
 277                 odhcp6c_clear_state(STATE_SNTP_IP);
 278                 odhcp6c_clear_state(STATE_NTP_IP);
 279                 odhcp6c_clear_state(STATE_NTP_FQDN);
 280                 odhcp6c_clear_state(STATE_SIP_IP);
 281                 odhcp6c_clear_state(STATE_SIP_FQDN);
 282                 dhcpv6_set_ia_mode(ia_na_mode, ia_pd_mode);
 283                 bound = false;
 284
 285                 syslog(LOG_NOTICE, "(re)starting transaction on %s", ifname);
 286
 287                 signal_usr1 = signal_usr2 = false;
 288                 int mode = dhcpv6_request(DHCPV6_MSG_SOLICIT);
 289                 odhcp6c_signal_process();
 290
 291                 if (mode < 0)
 292                         continue;
 293
 294                 do {
 295                         int res = dhcpv6_request(mode == DHCPV6_STATELESS ?
 296                                         DHCPV6_MSG_INFO_REQ : DHCPV6_MSG_REQUEST);
 297                         bool signalled = odhcp6c_signal_process();
 298
 299                         if (res > 0)
 300                                 break;
 301                         else if (signalled) {
 302                                 mode = -1;
 303                                 break;
 304                         }
 305
 306                         mode = dhcpv6_promote_server_cand();
 307                 } while (mode > DHCPV6_UNKNOWN);
 308
 309                 if (mode < 0)
 310                         continue;
 311
 312                 switch (mode) {
 313                 case DHCPV6_STATELESS:
 314                         bound = true;
 315                         syslog(LOG_NOTICE, "entering stateless-mode on %s", ifname);
 316
 317                         while (!signal_usr2 && !signal_term) {
 318                                 signal_usr1 = false;
 319                                 script_call("informed");
 320
 321                                 int res = dhcpv6_poll_reconfigure();
 322                                 odhcp6c_signal_process();
 323
 324                                 if (res > 0)
 325                                         continue;
 326
 327                                 if (signal_usr1) {
 328                                         signal_usr1 = false; // Acknowledged
 329                                         continue;
 330                                 }
 331                                 if (signal_usr2 || signal_term)
 332                                         break;
 333
 334                                 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
 335                                 odhcp6c_signal_process();
 336                                 if (signal_usr1)
 337                                         continue;
 338                                 else if (res < 0)
 339                                         break;
 340                         }
 341                         break;
 342
 343                 case DHCPV6_STATEFUL:
 344                         script_call("bound");
 345                         bound = true;
 346                         syslog(LOG_NOTICE, "entering stateful-mode on %s", ifname);
 347 #ifdef EXT_BFD_PING
 348                         if (bfd_interval > 0)
 349                                 bfd_start(ifname, bfd_loss, bfd_interval);
 350 #endif
 351
 352                         while (!signal_usr2 && !signal_term) {
 353                                 // Renew Cycle
 354                                 // Wait for T1 to expire or until we get a reconfigure
 355                                 int res = dhcpv6_poll_reconfigure();
 356                                 odhcp6c_signal_process();
 357                                 if (res > 0) {
 358                                         script_call("updated");
 359                                         continue;
 360                                 }
 361
 362                                 // Handle signal, if necessary
 363                                 if (signal_usr1)
 364                                         signal_usr1 = false; // Acknowledged
 365                                 if (signal_usr2 || signal_term)
 366                                         break; // Other signal type
 367
 368                                 // Send renew as T1 expired
 369                                 size_t ia_pd_len, ia_na_len;
 370                                 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
 371                                 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
 372
 373                                 // If we have any IAs, send renew, otherwise request
 374                                 if (ia_pd_len == 0 && ia_na_len == 0)
 375                                         res = dhcpv6_request(DHCPV6_MSG_REQUEST);
 376                                 else
 377                                         res = dhcpv6_request(DHCPV6_MSG_RENEW);
 378
 379                                 odhcp6c_signal_process();
 380                                 if (res > 0) { // Renew was succesfull
 381                                         // Publish updates
 382                                         script_call("updated");
 383                                         continue; // Renew was successful
 384                                 }
 385
 386                                 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
 387
 388                                 // If we have IAs, try rebind otherwise restart
 389                                 res = dhcpv6_request(DHCPV6_MSG_REBIND);
 390                                 odhcp6c_signal_process();
 391
 392                                 if (res > 0)
 393                                         script_call("rebound");
 394                                 else {
 395 #ifdef EXT_BFD_PING
 396                                         bfd_stop();
 397 #endif
 398                                         break;
 399                                 }
 400                         }
 401                         break;
 402
 403                 default:
 404                         break;
 405                 }
 406
 407                 size_t ia_pd_len, ia_na_len, server_id_len;
 408                 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
 409                 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
 410                 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
 411
 412                 // Add all prefixes to lost prefixes
 413                 bound = false;
 414                 script_call("unbound");
 415
 416                 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0) && release)
 417                         dhcpv6_request(DHCPV6_MSG_RELEASE);
 418
 419                 odhcp6c_clear_state(STATE_IA_NA);
 420                 odhcp6c_clear_state(STATE_IA_PD);
 421         }
 422
 423         script_call("stopped");
 424         return 0;
 425 }
 426
 427
 428 static int usage(void)
 429 {
 430         const char buf[] =
 431         "Usage: odhcp6c [options] <interface>\n"
 432         "\nFeature options:\n"
 433         "       -S <time>       Wait at least <time> sec for a DHCP-server (0)\n"
 434         "       -N <mode>       Mode for requesting addresses [try|force|none]\n"
 435         "       -P <length>     Request IPv6-Prefix (0 = auto)\n"
 436         "       -F              Force IPv6-Prefix\n"
 437         "       -V <hex-string> Set vendor-class option. string length must be a multiple of 2\n"
 438 #ifdef EXT_BFD_PING
 439         "       -B <interval>   Enable BFD ping check\n"
 440 #endif
 441         "       -c <clientid>   Override client-ID (base-16 encoded)\n"
 442         "       -i <iface-id>   Use a custom interface identifier for RA handling\n"
 443         "       -r <options>    Options to be requested (comma-separated)\n"
 444         "       -R              Do not request any options except those specified with -r\n"
 445         "       -s <script>     Status update script (/usr/sbin/odhcp6c-update)\n"
 446         "       -a              Don't send Accept Reconfigure option\n"
 447         "       -f              Don't send Client FQDN option\n"
 448         "       -k              Don't send a RELEASE when stopping\n"
 449         "       -t <seconds>    Maximum timeout for DHCPv6-SOLICIT (120)\n"
 450         "\nInvocation options:\n"
 451         "       -p <pidfile>    Set pidfile (/var/run/odhcp6c.pid)\n"
 452         "       -d              Daemonize\n"
 453         "       -e              Write logmessages to stderr\n"
 454         //"     -v              Increase logging verbosity\n"
 455         "       -h              Show this help\n\n";
 456         write(STDERR_FILENO, buf, sizeof(buf));
 457         return 1;
 458 }
 459
 460
 461 // Don't want to pull-in librt and libpthread just for a monotonic clock...
 462 uint64_t odhcp6c_get_milli_time(void)
 463 {
 464         struct timespec t = {0, 0};
 465         syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
 466         return t.tv_sec * 1000 + t.tv_nsec / 1000000;
 467 }
 468
 469
 470 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
 471 {
 472         if (len == 0)
 473                 return state_data[state] + state_len[state];
 474         else if (state_len[state] + len > 1024)
 475                 return NULL;
 476
 477         uint8_t *n = realloc(state_data[state], state_len[state] + len);
 478         if (n || state_len[state] + len == 0) {
 479                 state_data[state] = n;
 480                 n += state_len[state];
 481                 state_len[state] += len;
 482         }
 483         return n;
 484 }
 485
 486
 487 bool odhcp6c_signal_process(void)
 488 {
 489         while (signal_io) {
 490                 signal_io = false;
 491
 492                 bool ra_updated = ra_process();
 493
 494                 if (ra_link_up())
 495                         signal_usr2 = true;
 496
 497                 if (ra_updated && (bound || allow_slaac_only == 0))
 498                         script_call("ra-updated"); // Immediate process urgent events
 499                 else if (ra_updated && !bound && allow_slaac_only > 0)
 500                         script_delay_call("ra-updated", allow_slaac_only);
 501
 502 #ifdef EXT_BFD_PING
 503                 bfd_receive();
 504 #endif
 505         }
 506
 507         return signal_usr1 || signal_usr2 || signal_term;
 508 }
 509
 510
 511 void odhcp6c_clear_state(enum odhcp6c_state state)
 512 {
 513         state_len[state] = 0;
 514 }
 515
 516
 517 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
 518 {
 519         uint8_t *n = odhcp6c_resize_state(state, len);
 520         if (n)
 521                 memcpy(n, data, len);
 522 }
 523
 524 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len)
 525 {
 526         ssize_t len_after = state_len[state] - offset;
 527         if (len_after < 0)
 528                 return;
 529
 530         uint8_t *n = odhcp6c_resize_state(state, len);
 531         if (n) {
 532                 uint8_t *sdata = state_data[state];
 533
 534                 memmove(sdata + offset + len, sdata + offset, len_after);
 535                 memcpy(sdata + offset, data, len);
 536         }
 537 }
 538
 539 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
 540 {
 541         uint8_t *data = state_data[state];
 542         ssize_t len_after = state_len[state] - (offset + len);
 543         if (len_after < 0)
 544                 return state_len[state];
 545
 546         memmove(data + offset, data + offset + len, len_after);
 547         return state_len[state] -= len;
 548 }
 549
 550
 551 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len)
 552 {
 553         *len = state_len[state];
 554         void *data = state_data[state];
 555
 556         state_len[state] = 0;
 557         state_data[state] = NULL;
 558
 559         return data;
 560 }
 561
 562
 563 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
 564 {
 565         *len = state_len[state];
 566         return state_data[state];
 567 }
 568
 569
 570 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
 571 {
 572         size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
 573         struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
 574         struct odhcp6c_entry *x = NULL;
 575
 576         for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
 577                 if (!memcmp(c, new, cmplen))
 578                         return c;
 579
 580         return NULL;
 581 }
 582
 583
 584 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
 585 {
 586         size_t len;
 587         struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
 588         struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
 589
 590         if (x && x->valid > new->valid && new->valid < safe)
 591                 new->valid = safe;
 592
 593         if (new->valid > 0) {
 594                 if (x) {
 595                         if (new->valid >= x->valid && new->valid != UINT32_MAX &&
 596                                         new->valid - x->valid < 60 &&
 597                                         new->preferred >= x->preferred &&
 598                                         new->preferred != UINT32_MAX &&
 599                                         new->preferred - x->preferred < 60 &&
 600                                         x->class == new->class)
 601                                 return false;
 602                         x->valid = new->valid;
 603                         x->preferred = new->preferred;
 604                         x->t1 = new->t1;
 605                         x->t2 = new->t2;
 606                         x->class = new->class;
 607                         x->iaid = new->iaid;
 608                 } else {
 609                         odhcp6c_add_state(state, new, sizeof(*new));
 610                 }
 611         } else if (x) {
 612                 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
 613         }
 614         return true;
 615 }
 616
 617
 618 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
 619 {
 620         return odhcp6c_update_entry_safe(state, new, 0);
 621 }
 622
 623
 624 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
 625 {
 626         size_t len;
 627         struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
 628         for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
 629                 if (c->t1 < elapsed)
 630                         c->t1 = 0;
 631                 else if (c->t1 != UINT32_MAX)
 632                         c->t1 -= elapsed;
 633
 634                 if (c->t2 < elapsed)
 635                         c->t2 = 0;
 636                 else if (c->t2 != UINT32_MAX)
 637                         c->t2 -= elapsed;
 638
 639                 if (c->preferred < elapsed)
 640                         c->preferred = 0;
 641                 else if (c->preferred != UINT32_MAX)
 642                         c->preferred -= elapsed;
 643
 644                 if (c->valid < elapsed)
 645                         c->valid = 0;
 646                 else if (c->valid != UINT32_MAX)
 647                         c->valid -= elapsed;
 648
 649                 if (!c->valid)
 650                         odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
 651         }
 652 }
 653
 654
 655 void odhcp6c_expire(void)
 656 {
 657         time_t now = odhcp6c_get_milli_time() / 1000;
 658         uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
 659         last_update = now;
 660
 661         odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
 662         odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
 663         odhcp6c_expire_list(STATE_RA_DNS, elapsed);
 664         odhcp6c_expire_list(STATE_IA_NA, elapsed);
 665         odhcp6c_expire_list(STATE_IA_PD, elapsed);
 666 }
 667
 668
 669 uint32_t odhcp6c_elapsed(void)
 670 {
 671         return odhcp6c_get_milli_time() / 1000 - last_update;
 672 }
 673
 674
 675 void odhcp6c_random(void *buf, size_t len)
 676 {
 677         read(urandom_fd, buf, len);
 678 }
 679
 680 bool odhcp6c_is_bound(void)
 681 {
 682         return bound;
 683 }
 684
 685 static void sighandler(int signal)
 686 {
 687         if (signal == SIGCHLD)
 688                 while (waitpid(-1, NULL, WNOHANG) > 0);
 689         else if (signal == SIGUSR1)
 690                 signal_usr1 = true;
 691         else if (signal == SIGUSR2)
 692                 signal_usr2 = true;
 693         else if (signal == SIGIO)
 694                 signal_io = true;
 695         else
 696                 signal_term = true;
 697 }