2 * Copyright (C) 2012-2014 Steven Barth <steven@midlink.org>
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.
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.
29 #include <sys/syscall.h>
30 #include <arpa/inet.h>
40 static void sighandler(int signal);
41 static int usage(void);
43 static uint8_t *state_data[_STATE_MAX] = {NULL};
44 static size_t state_len[_STATE_MAX] = {0};
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;
51 static int urandom_fd = -1, allow_slaac_only = 0;
52 static bool bound = false, release = true;
53 static time_t last_update = 0;
55 int main(_unused int argc, char* const argv[])
57 // Allocate ressources
58 const char *pidfile = NULL;
59 const char *script = "/usr/sbin/odhcp6c-update";
64 enum odhcp6c_ia_mode ia_na_mode = IA_MODE_TRY;
65 enum odhcp6c_ia_mode ia_pd_mode = IA_MODE_NONE;
66 int ia_pd_iaid_index = 0;
67 static struct in6_addr ifid = IN6ADDR_ANY_INIT;
68 int sol_timeout = DHCPV6_SOL_MAX_RT;
71 int bfd_interval = 0, bfd_loss = 3;
74 bool help = false, daemonize = false;
77 unsigned int client_options = DHCPV6_CLIENT_FQDN | DHCPV6_ACCEPT_RECONFIGURE;
79 while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Rs:kt:hedp:fa")) != -1) {
82 allow_slaac_only = (optarg) ? atoi(optarg) : -1;
86 if (!strcmp(optarg, "force")) {
87 ia_na_mode = IA_MODE_FORCE;
88 allow_slaac_only = -1;
89 } else if (!strcmp(optarg, "none")) {
90 ia_na_mode = IA_MODE_NONE;
91 } else if (!strcmp(optarg, "try")) {
92 ia_na_mode = IA_MODE_TRY;
99 l = script_unhexlify(buf, sizeof(buf), optarg);
103 odhcp6c_add_state(STATE_VENDORCLASS, buf, l);
107 if (ia_pd_mode == IA_MODE_NONE)
108 ia_pd_mode = IA_MODE_TRY;
110 if (allow_slaac_only >= 0 && allow_slaac_only < 10)
111 allow_slaac_only = 10;
116 int prefix_length = strtoul(optarg, &iaid_begin, 10);
118 if (*iaid_begin != '\0' && *iaid_begin != ',') {
119 syslog(LOG_ERR, "invalid argument: '%s'", optarg);
123 struct odhcp6c_request_prefix prefix = { 0, prefix_length };
125 if (*iaid_begin == ',' && (iaid_len = strlen(iaid_begin)) > 1)
126 memcpy(&prefix.iaid, iaid_begin + 1, iaid_len > 4 ? 4 : iaid_len);
128 prefix.iaid = ++ia_pd_iaid_index;
130 odhcp6c_add_state(STATE_IA_PD_INIT, &prefix, sizeof(prefix));
135 allow_slaac_only = -1;
136 ia_pd_mode = IA_MODE_FORCE;
141 bfd_interval = atoi(optarg);
146 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
149 buf[1] = DHCPV6_OPT_CLIENTID;
152 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
159 if (inet_pton(AF_INET6, optarg, &ifid) != 1)
166 opttype = htons(strtoul(optarg, &optpos, 10));
167 if (optpos == optarg)
171 odhcp6c_add_state(STATE_ORO, &opttype, 2);
176 client_options |= DHCPV6_STRICT_OPTIONS;
188 sol_timeout = atoi(optarg);
192 logopt |= LOG_PERROR;
204 client_options &= ~DHCPV6_CLIENT_FQDN;
208 client_options &= ~DHCPV6_ACCEPT_RECONFIGURE;
217 openlog("odhcp6c", logopt, LOG_DAEMON);
218 const char *ifname = argv[optind];
223 signal(SIGIO, sighandler);
224 signal(SIGHUP, sighandler);
225 signal(SIGINT, sighandler);
226 signal(SIGCHLD, sighandler);
227 signal(SIGTERM, sighandler);
228 signal(SIGUSR1, sighandler);
229 signal(SIGUSR2, sighandler);
231 if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
232 init_dhcpv6(ifname, client_options, sol_timeout) ||
233 ra_init(ifname, &ifid) || script_init(script, ifname)) {
234 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
239 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
241 syslog(LOG_ERR, "Failed to daemonize: %s",
248 snprintf(pidbuf, sizeof(pidbuf),
249 "/var/run/odhcp6c.%s.pid", ifname);
253 int fd = open(pidfile, O_WRONLY | O_CREAT);
256 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
262 script_call("started");
264 while (!signal_term) { // Main logic
265 odhcp6c_clear_state(STATE_SERVER_ID);
266 odhcp6c_clear_state(STATE_IA_NA);
267 odhcp6c_clear_state(STATE_IA_PD);
268 odhcp6c_clear_state(STATE_SNTP_IP);
269 odhcp6c_clear_state(STATE_NTP_IP);
270 odhcp6c_clear_state(STATE_NTP_FQDN);
271 odhcp6c_clear_state(STATE_SIP_IP);
272 odhcp6c_clear_state(STATE_SIP_FQDN);
273 dhcpv6_set_ia_mode(ia_na_mode, ia_pd_mode);
276 syslog(LOG_NOTICE, "(re)starting transaction on %s", ifname);
278 signal_usr1 = signal_usr2 = false;
279 int mode = dhcpv6_request(DHCPV6_MSG_SOLICIT);
280 odhcp6c_signal_process();
286 int res = dhcpv6_request(mode == DHCPV6_STATELESS ?
287 DHCPV6_MSG_INFO_REQ : DHCPV6_MSG_REQUEST);
288 bool signalled = odhcp6c_signal_process();
292 else if (signalled) {
297 mode = dhcpv6_promote_server_cand();
298 } while (mode > DHCPV6_UNKNOWN);
304 case DHCPV6_STATELESS:
306 syslog(LOG_NOTICE, "entering stateless-mode on %s", ifname);
308 while (!signal_usr2 && !signal_term) {
310 script_call("informed");
312 int res = dhcpv6_poll_reconfigure();
313 odhcp6c_signal_process();
319 signal_usr1 = false; // Acknowledged
322 if (signal_usr2 || signal_term)
325 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
326 odhcp6c_signal_process();
334 case DHCPV6_STATEFUL:
335 script_call("bound");
337 syslog(LOG_NOTICE, "entering stateful-mode on %s", ifname);
339 if (bfd_interval > 0)
340 bfd_start(ifname, bfd_loss, bfd_interval);
343 while (!signal_usr2 && !signal_term) {
345 // Wait for T1 to expire or until we get a reconfigure
346 int res = dhcpv6_poll_reconfigure();
347 odhcp6c_signal_process();
349 script_call("updated");
353 // Handle signal, if necessary
355 signal_usr1 = false; // Acknowledged
356 if (signal_usr2 || signal_term)
357 break; // Other signal type
359 // Send renew as T1 expired
360 size_t ia_pd_len, ia_na_len;
361 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
362 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
364 // If we have any IAs, send renew, otherwise request
365 if (ia_pd_len == 0 && ia_na_len == 0)
366 res = dhcpv6_request(DHCPV6_MSG_REQUEST);
368 res = dhcpv6_request(DHCPV6_MSG_RENEW);
370 odhcp6c_signal_process();
371 if (res > 0) { // Renew was succesfull
373 script_call("updated");
374 continue; // Renew was successful
377 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
379 // If we have IAs, try rebind otherwise restart
380 res = dhcpv6_request(DHCPV6_MSG_REBIND);
381 odhcp6c_signal_process();
384 script_call("rebound");
398 size_t ia_pd_len, ia_na_len, server_id_len;
399 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
400 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
401 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
403 // Add all prefixes to lost prefixes
405 script_call("unbound");
407 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0) && release)
408 dhcpv6_request(DHCPV6_MSG_RELEASE);
410 odhcp6c_clear_state(STATE_IA_NA);
411 odhcp6c_clear_state(STATE_IA_PD);
414 script_call("stopped");
419 static int usage(void)
422 "Usage: odhcp6c [options] <interface>\n"
423 "\nFeature options:\n"
424 " -S <time> Wait at least <time> sec for a DHCP-server (0)\n"
425 " -N <mode> Mode for requesting addresses [try|force|none]\n"
426 " -P <length> Request IPv6-Prefix (0 = auto)\n"
427 " -F Force IPv6-Prefix\n"
428 " -V <hex-string> Set vendor-class option. string length must be a multiple of 2\n"
430 " -B <interval> Enable BFD ping check\n"
432 " -c <clientid> Override client-ID (base-16 encoded)\n"
433 " -i <iface-id> Use a custom interface identifier for RA handling\n"
434 " -r <options> Options to be requested (comma-separated)\n"
435 " -R Do not request any options except those specified with -r\n"
436 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
437 " -a Don't send Accept Reconfigure option\n"
438 " -f Don't send Client FQDN option\n"
439 " -k Don't send a RELEASE when stopping\n"
440 " -t <seconds> Maximum timeout for DHCPv6-SOLICIT (120)\n"
441 "\nInvocation options:\n"
442 " -p <pidfile> Set pidfile (/var/run/odhcp6c.pid)\n"
444 " -e Write logmessages to stderr\n"
445 //" -v Increase logging verbosity\n"
446 " -h Show this help\n\n";
447 write(STDERR_FILENO, buf, sizeof(buf));
452 // Don't want to pull-in librt and libpthread just for a monotonic clock...
453 uint64_t odhcp6c_get_milli_time(void)
455 struct timespec t = {0, 0};
456 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
457 return t.tv_sec * 1000 + t.tv_nsec / 1000000;
461 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
464 return state_data[state] + state_len[state];
465 else if (state_len[state] + len > 1024)
468 uint8_t *n = realloc(state_data[state], state_len[state] + len);
469 if (n || state_len[state] + len == 0) {
470 state_data[state] = n;
471 n += state_len[state];
472 state_len[state] += len;
478 bool odhcp6c_signal_process(void)
483 bool ra_updated = ra_process();
488 if (ra_updated && (bound || allow_slaac_only == 0))
489 script_call("ra-updated"); // Immediate process urgent events
490 else if (ra_updated && !bound && allow_slaac_only > 0)
491 script_delay_call("ra-updated", allow_slaac_only);
498 return signal_usr1 || signal_usr2 || signal_term;
502 void odhcp6c_clear_state(enum odhcp6c_state state)
504 state_len[state] = 0;
508 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
510 uint8_t *n = odhcp6c_resize_state(state, len);
512 memcpy(n, data, len);
515 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len)
517 ssize_t len_after = state_len[state] - offset;
521 uint8_t *n = odhcp6c_resize_state(state, len);
523 uint8_t *sdata = state_data[state];
525 memmove(sdata + offset + len, sdata + offset, len_after);
526 memcpy(sdata + offset, data, len);
530 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
532 uint8_t *data = state_data[state];
533 ssize_t len_after = state_len[state] - (offset + len);
535 return state_len[state];
537 memmove(data + offset, data + offset + len, len_after);
538 return state_len[state] -= len;
542 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len)
544 *len = state_len[state];
545 void *data = state_data[state];
547 state_len[state] = 0;
548 state_data[state] = NULL;
554 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
556 *len = state_len[state];
557 return state_data[state];
561 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
563 size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
564 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
565 struct odhcp6c_entry *x = NULL;
567 for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
568 if (!memcmp(c, new, cmplen))
575 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
578 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
579 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
581 if (x && x->valid > new->valid && new->valid < safe)
584 if (new->valid > 0) {
586 if (new->valid >= x->valid && new->valid - x->valid < 60 &&
587 new->preferred >= x->preferred &&
588 new->preferred - x->preferred < 60 &&
589 x->class == new->class)
591 x->valid = new->valid;
592 x->preferred = new->preferred;
595 x->class = new->class;
598 odhcp6c_add_state(state, new, sizeof(*new));
601 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
607 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
609 return odhcp6c_update_entry_safe(state, new, 0);
613 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
616 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
617 for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
620 else if (c->t1 != UINT32_MAX)
625 else if (c->t2 != UINT32_MAX)
628 if (c->preferred < elapsed)
630 else if (c->preferred != UINT32_MAX)
631 c->preferred -= elapsed;
633 if (c->valid < elapsed)
635 else if (c->valid != UINT32_MAX)
639 odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
644 void odhcp6c_expire(void)
646 time_t now = odhcp6c_get_milli_time() / 1000;
647 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
650 odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
651 odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
652 odhcp6c_expire_list(STATE_RA_DNS, elapsed);
653 odhcp6c_expire_list(STATE_IA_NA, elapsed);
654 odhcp6c_expire_list(STATE_IA_PD, elapsed);
658 uint32_t odhcp6c_elapsed(void)
660 return odhcp6c_get_milli_time() / 1000 - last_update;
664 void odhcp6c_random(void *buf, size_t len)
666 read(urandom_fd, buf, len);
669 bool odhcp6c_is_bound(void)
674 static void sighandler(int signal)
676 if (signal == SIGCHLD)
677 while (waitpid(-1, NULL, WNOHANG) > 0);
678 else if (signal == SIGUSR1)
680 else if (signal == SIGUSR2)
682 else if (signal == SIGIO)