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 static unsigned int min_update_interval = DEFAULT_MIN_UPDATE_INTERVAL;
57 int main(_unused int argc, char* const argv[])
59 // Allocate ressources
60 const char *pidfile = NULL;
61 const char *script = "/usr/sbin/odhcp6c-update";
67 enum odhcp6c_ia_mode ia_na_mode = IA_MODE_TRY;
68 enum odhcp6c_ia_mode ia_pd_mode = IA_MODE_NONE;
69 int ia_pd_iaid_index = 0;
70 static struct in6_addr ifid = IN6ADDR_ANY_INIT;
71 int sol_timeout = DHCPV6_SOL_MAX_RT;
74 int bfd_interval = 0, bfd_loss = 3;
77 bool help = false, daemonize = false;
80 unsigned int client_options = DHCPV6_CLIENT_FQDN | DHCPV6_ACCEPT_RECONFIGURE;
82 while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:s:kt:m:hedp:fa")) != -1) {
85 allow_slaac_only = (optarg) ? atoi(optarg) : -1;
89 if (!strcmp(optarg, "force")) {
90 ia_na_mode = IA_MODE_FORCE;
91 allow_slaac_only = -1;
92 } else if (!strcmp(optarg, "none")) {
93 ia_na_mode = IA_MODE_NONE;
94 } else if (!strcmp(optarg, "try")) {
95 ia_na_mode = IA_MODE_TRY;
102 l = script_unhexlify(buf, sizeof(buf), optarg);
106 odhcp6c_add_state(STATE_VENDORCLASS, buf, l);
110 if (ia_pd_mode == IA_MODE_NONE)
111 ia_pd_mode = IA_MODE_TRY;
113 if (allow_slaac_only >= 0 && allow_slaac_only < 10)
114 allow_slaac_only = 10;
119 int prefix_length = strtoul(optarg, &iaid_begin, 10);
121 if (*iaid_begin != '\0' && *iaid_begin != ',' && *iaid_begin != ':') {
122 syslog(LOG_ERR, "invalid argument: '%s'", optarg);
126 struct odhcp6c_request_prefix prefix = { 0, prefix_length };
128 if (*iaid_begin == ',' && (iaid_len = strlen(iaid_begin)) > 1)
129 memcpy(&prefix.iaid, iaid_begin + 1, iaid_len > 4 ? 4 : iaid_len);
130 else if (*iaid_begin == ':')
131 prefix.iaid = htonl((uint32_t)strtoul(&iaid_begin[1], NULL, 16));
133 prefix.iaid = htonl(++ia_pd_iaid_index);
135 odhcp6c_add_state(STATE_IA_PD_INIT, &prefix, sizeof(prefix));
140 allow_slaac_only = -1;
141 ia_pd_mode = IA_MODE_FORCE;
146 bfd_interval = atoi(optarg);
151 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
154 buf[1] = DHCPV6_OPT_CLIENTID;
157 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
164 if (inet_pton(AF_INET6, optarg, &ifid) != 1)
171 opttype = htons(strtoul(optarg, &optpos, 10));
172 if (optpos == optarg)
176 odhcp6c_add_state(STATE_ORO, &opttype, 2);
181 client_options |= DHCPV6_STRICT_OPTIONS;
185 optlen = htons(strlen(optarg));
186 odhcp6c_add_state(STATE_USERCLASS, &optlen, 2);
187 odhcp6c_add_state(STATE_USERCLASS, optarg, strlen(optarg));
199 sol_timeout = atoi(optarg);
203 min_update_interval = atoi(optarg);
207 logopt |= LOG_PERROR;
219 client_options &= ~DHCPV6_CLIENT_FQDN;
223 client_options &= ~DHCPV6_ACCEPT_RECONFIGURE;
232 openlog("odhcp6c", logopt, LOG_DAEMON);
233 const char *ifname = argv[optind];
238 signal(SIGIO, sighandler);
239 signal(SIGHUP, sighandler);
240 signal(SIGINT, sighandler);
241 signal(SIGCHLD, sighandler);
242 signal(SIGTERM, sighandler);
243 signal(SIGUSR1, sighandler);
244 signal(SIGUSR2, sighandler);
246 if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
247 init_dhcpv6(ifname, client_options, sol_timeout) ||
248 ra_init(ifname, &ifid) || script_init(script, ifname)) {
249 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
254 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
256 syslog(LOG_ERR, "Failed to daemonize: %s",
263 snprintf(pidbuf, sizeof(pidbuf),
264 "/var/run/odhcp6c.%s.pid", ifname);
268 int fd = open(pidfile, O_WRONLY | O_CREAT, 0644);
271 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
277 script_call("started");
279 while (!signal_term) { // Main logic
280 odhcp6c_clear_state(STATE_SERVER_ID);
281 odhcp6c_clear_state(STATE_IA_NA);
282 odhcp6c_clear_state(STATE_IA_PD);
283 odhcp6c_clear_state(STATE_SNTP_IP);
284 odhcp6c_clear_state(STATE_NTP_IP);
285 odhcp6c_clear_state(STATE_NTP_FQDN);
286 odhcp6c_clear_state(STATE_SIP_IP);
287 odhcp6c_clear_state(STATE_SIP_FQDN);
288 dhcpv6_set_ia_mode(ia_na_mode, ia_pd_mode);
291 syslog(LOG_NOTICE, "(re)starting transaction on %s", ifname);
293 signal_usr1 = signal_usr2 = false;
294 int mode = dhcpv6_request(DHCPV6_MSG_SOLICIT);
295 odhcp6c_signal_process();
301 int res = dhcpv6_request(mode == DHCPV6_STATELESS ?
302 DHCPV6_MSG_INFO_REQ : DHCPV6_MSG_REQUEST);
303 bool signalled = odhcp6c_signal_process();
307 else if (signalled) {
312 mode = dhcpv6_promote_server_cand();
313 } while (mode > DHCPV6_UNKNOWN);
319 case DHCPV6_STATELESS:
321 syslog(LOG_NOTICE, "entering stateless-mode on %s", ifname);
323 while (!signal_usr2 && !signal_term) {
325 script_call("informed");
327 int res = dhcpv6_poll_reconfigure();
328 odhcp6c_signal_process();
334 signal_usr1 = false; // Acknowledged
337 if (signal_usr2 || signal_term)
340 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
341 odhcp6c_signal_process();
349 case DHCPV6_STATEFUL:
350 script_call("bound");
352 syslog(LOG_NOTICE, "entering stateful-mode on %s", ifname);
354 if (bfd_interval > 0)
355 bfd_start(ifname, bfd_loss, bfd_interval);
358 while (!signal_usr2 && !signal_term) {
360 // Wait for T1 to expire or until we get a reconfigure
361 int res = dhcpv6_poll_reconfigure();
362 odhcp6c_signal_process();
364 script_call("updated");
368 // Handle signal, if necessary
370 signal_usr1 = false; // Acknowledged
371 if (signal_usr2 || signal_term)
372 break; // Other signal type
374 // Send renew as T1 expired
375 res = dhcpv6_request(DHCPV6_MSG_RENEW);
376 odhcp6c_signal_process();
377 if (res > 0) { // Renew was succesfull
379 script_call("updated");
380 continue; // Renew was successful
383 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
385 size_t ia_pd_len, ia_na_len;
386 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
387 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
389 if (ia_pd_len == 0 && ia_na_len == 0)
392 // If we have IAs, try rebind otherwise restart
393 res = dhcpv6_request(DHCPV6_MSG_REBIND);
394 odhcp6c_signal_process();
397 script_call("rebound");
411 size_t ia_pd_len, ia_na_len, server_id_len;
412 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
413 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
414 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
416 // Add all prefixes to lost prefixes
418 script_call("unbound");
420 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0) && release)
421 dhcpv6_request(DHCPV6_MSG_RELEASE);
423 odhcp6c_clear_state(STATE_IA_NA);
424 odhcp6c_clear_state(STATE_IA_PD);
427 script_call("stopped");
432 static int usage(void)
435 "Usage: odhcp6c [options] <interface>\n"
436 "\nFeature options:\n"
437 " -S <time> Wait at least <time> sec for a DHCP-server (0)\n"
438 " -N <mode> Mode for requesting addresses [try|force|none]\n"
439 " -P <length> Request IPv6-Prefix (0 = auto)\n"
440 " -F Force IPv6-Prefix\n"
441 " -V <class> Set vendor-class option (base-16 encoded)\n"
443 " -B <interval> Enable BFD ping check\n"
445 " -u <user-class> Set user-class option string\n"
446 " -c <clientid> Override client-ID (base-16 encoded)\n"
447 " -i <iface-id> Use a custom interface identifier for RA handling\n"
448 " -r <options> Options to be requested (comma-separated)\n"
449 " -R Do not request any options except those specified with -r\n"
450 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
451 " -a Don't send Accept Reconfigure option\n"
452 " -f Don't send Client FQDN option\n"
453 " -k Don't send a RELEASE when stopping\n"
454 " -t <seconds> Maximum timeout for DHCPv6-SOLICIT (3600)\n"
455 " -m <seconds> Minimum time between accepting updates (30)\n"
456 "\nInvocation options:\n"
457 " -p <pidfile> Set pidfile (/var/run/odhcp6c.pid)\n"
459 " -e Write logmessages to stderr\n"
460 //" -v Increase logging verbosity\n"
461 " -h Show this help\n\n";
462 write(STDERR_FILENO, buf, sizeof(buf));
467 // Don't want to pull-in librt and libpthread just for a monotonic clock...
468 uint64_t odhcp6c_get_milli_time(void)
470 struct timespec t = {0, 0};
471 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
472 return ((uint64_t)t.tv_sec) * 1000 + ((uint64_t)t.tv_nsec) / 1000000;
476 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
479 return state_data[state] + state_len[state];
480 else if (state_len[state] + len > 1024)
483 uint8_t *n = realloc(state_data[state], state_len[state] + len);
484 if (n || state_len[state] + len == 0) {
485 state_data[state] = n;
486 n += state_len[state];
487 state_len[state] += len;
493 bool odhcp6c_signal_process(void)
498 bool ra_updated = ra_process();
503 if (ra_updated && (bound || allow_slaac_only == 0))
504 script_call("ra-updated"); // Immediate process urgent events
505 else if (ra_updated && !bound && allow_slaac_only > 0)
506 script_delay_call("ra-updated", allow_slaac_only);
513 return signal_usr1 || signal_usr2 || signal_term;
517 void odhcp6c_clear_state(enum odhcp6c_state state)
519 state_len[state] = 0;
523 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
525 uint8_t *n = odhcp6c_resize_state(state, len);
527 memcpy(n, data, len);
530 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len)
532 ssize_t len_after = state_len[state] - offset;
536 uint8_t *n = odhcp6c_resize_state(state, len);
538 uint8_t *sdata = state_data[state];
540 memmove(sdata + offset + len, sdata + offset, len_after);
541 memcpy(sdata + offset, data, len);
545 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
547 uint8_t *data = state_data[state];
548 ssize_t len_after = state_len[state] - (offset + len);
550 return state_len[state];
552 memmove(data + offset, data + offset + len, len_after);
553 return state_len[state] -= len;
557 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len)
559 *len = state_len[state];
560 void *data = state_data[state];
562 state_len[state] = 0;
563 state_data[state] = NULL;
569 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
571 *len = state_len[state];
572 return state_data[state];
576 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
578 size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
579 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
580 struct odhcp6c_entry *x = NULL;
582 for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
583 if (!memcmp(c, new, cmplen))
590 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
593 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
594 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
596 if (x && x->valid > new->valid && new->valid < safe)
599 if (new->valid > 0) {
601 if (new->valid >= x->valid && new->valid != UINT32_MAX &&
602 new->valid - x->valid < min_update_interval &&
603 new->preferred >= x->preferred &&
604 new->preferred != UINT32_MAX &&
605 new->preferred - x->preferred < min_update_interval &&
606 x->class == new->class)
608 x->valid = new->valid;
609 x->preferred = new->preferred;
612 x->class = new->class;
615 odhcp6c_add_state(state, new, sizeof(*new));
618 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
624 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
626 return odhcp6c_update_entry_safe(state, new, 0);
630 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
633 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
634 for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
637 else if (c->t1 != UINT32_MAX)
642 else if (c->t2 != UINT32_MAX)
645 if (c->preferred < elapsed)
647 else if (c->preferred != UINT32_MAX)
648 c->preferred -= elapsed;
650 if (c->valid < elapsed)
652 else if (c->valid != UINT32_MAX)
656 odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
661 void odhcp6c_expire(void)
663 time_t now = odhcp6c_get_milli_time() / 1000;
664 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
667 odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
668 odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
669 odhcp6c_expire_list(STATE_RA_DNS, elapsed);
670 odhcp6c_expire_list(STATE_IA_NA, elapsed);
671 odhcp6c_expire_list(STATE_IA_PD, elapsed);
675 uint32_t odhcp6c_elapsed(void)
677 return odhcp6c_get_milli_time() / 1000 - last_update;
681 void odhcp6c_random(void *buf, size_t len)
683 read(urandom_fd, buf, len);
686 bool odhcp6c_is_bound(void)
691 static void sighandler(int signal)
693 if (signal == SIGCHLD)
694 while (waitpid(-1, NULL, WNOHANG) > 0);
695 else if (signal == SIGUSR1)
697 else if (signal == SIGUSR2)
699 else if (signal == SIGIO)