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";
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;
72 int bfd_interval = 0, bfd_loss = 3;
75 bool help = false, daemonize = false;
78 unsigned int client_options = DHCPV6_CLIENT_FQDN | DHCPV6_ACCEPT_RECONFIGURE;
80 while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:s:kt:hedp:fa")) != -1) {
83 allow_slaac_only = (optarg) ? atoi(optarg) : -1;
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;
100 l = script_unhexlify(buf, sizeof(buf), optarg);
104 odhcp6c_add_state(STATE_VENDORCLASS, buf, l);
108 if (ia_pd_mode == IA_MODE_NONE)
109 ia_pd_mode = IA_MODE_TRY;
111 if (allow_slaac_only >= 0 && allow_slaac_only < 10)
112 allow_slaac_only = 10;
117 int prefix_length = strtoul(optarg, &iaid_begin, 10);
119 if (*iaid_begin != '\0' && *iaid_begin != ',' && *iaid_begin != ':') {
120 syslog(LOG_ERR, "invalid argument: '%s'", optarg);
124 struct odhcp6c_request_prefix prefix = { 0, prefix_length };
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));
131 prefix.iaid = htonl(++ia_pd_iaid_index);
133 odhcp6c_add_state(STATE_IA_PD_INIT, &prefix, sizeof(prefix));
138 allow_slaac_only = -1;
139 ia_pd_mode = IA_MODE_FORCE;
144 bfd_interval = atoi(optarg);
149 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
152 buf[1] = DHCPV6_OPT_CLIENTID;
155 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
162 if (inet_pton(AF_INET6, optarg, &ifid) != 1)
169 opttype = htons(strtoul(optarg, &optpos, 10));
170 if (optpos == optarg)
174 odhcp6c_add_state(STATE_ORO, &opttype, 2);
179 client_options |= DHCPV6_STRICT_OPTIONS;
183 optlen = htons(strlen(optarg));
184 odhcp6c_add_state(STATE_USERCLASS, &optlen, 2);
185 odhcp6c_add_state(STATE_USERCLASS, optarg, strlen(optarg));
197 sol_timeout = atoi(optarg);
201 logopt |= LOG_PERROR;
213 client_options &= ~DHCPV6_CLIENT_FQDN;
217 client_options &= ~DHCPV6_ACCEPT_RECONFIGURE;
226 openlog("odhcp6c", logopt, LOG_DAEMON);
227 const char *ifname = argv[optind];
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);
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));
248 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
250 syslog(LOG_ERR, "Failed to daemonize: %s",
257 snprintf(pidbuf, sizeof(pidbuf),
258 "/var/run/odhcp6c.%s.pid", ifname);
262 int fd = open(pidfile, O_WRONLY | O_CREAT, 0644);
265 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
271 script_call("started");
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);
285 syslog(LOG_NOTICE, "(re)starting transaction on %s", ifname);
287 signal_usr1 = signal_usr2 = false;
288 int mode = dhcpv6_request(DHCPV6_MSG_SOLICIT);
289 odhcp6c_signal_process();
295 int res = dhcpv6_request(mode == DHCPV6_STATELESS ?
296 DHCPV6_MSG_INFO_REQ : DHCPV6_MSG_REQUEST);
297 bool signalled = odhcp6c_signal_process();
301 else if (signalled) {
306 mode = dhcpv6_promote_server_cand();
307 } while (mode > DHCPV6_UNKNOWN);
313 case DHCPV6_STATELESS:
315 syslog(LOG_NOTICE, "entering stateless-mode on %s", ifname);
317 while (!signal_usr2 && !signal_term) {
319 script_call("informed");
321 int res = dhcpv6_poll_reconfigure();
322 odhcp6c_signal_process();
328 signal_usr1 = false; // Acknowledged
331 if (signal_usr2 || signal_term)
334 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
335 odhcp6c_signal_process();
343 case DHCPV6_STATEFUL:
344 script_call("bound");
346 syslog(LOG_NOTICE, "entering stateful-mode on %s", ifname);
348 if (bfd_interval > 0)
349 bfd_start(ifname, bfd_loss, bfd_interval);
352 while (!signal_usr2 && !signal_term) {
354 // Wait for T1 to expire or until we get a reconfigure
355 int res = dhcpv6_poll_reconfigure();
356 odhcp6c_signal_process();
358 script_call("updated");
362 // Handle signal, if necessary
364 signal_usr1 = false; // Acknowledged
365 if (signal_usr2 || signal_term)
366 break; // Other signal type
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);
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);
377 res = dhcpv6_request(DHCPV6_MSG_RENEW);
379 odhcp6c_signal_process();
380 if (res > 0) { // Renew was succesfull
382 script_call("updated");
383 continue; // Renew was successful
386 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
388 // If we have IAs, try rebind otherwise restart
389 res = dhcpv6_request(DHCPV6_MSG_REBIND);
390 odhcp6c_signal_process();
393 script_call("rebound");
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);
412 // Add all prefixes to lost prefixes
414 script_call("unbound");
416 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0) && release)
417 dhcpv6_request(DHCPV6_MSG_RELEASE);
419 odhcp6c_clear_state(STATE_IA_NA);
420 odhcp6c_clear_state(STATE_IA_PD);
423 script_call("stopped");
428 static int usage(void)
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 <class> Set vendor-class option (base-16 encoded)\n"
439 " -B <interval> Enable BFD ping check\n"
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 (3600)\n"
450 "\nInvocation options:\n"
451 " -p <pidfile> Set pidfile (/var/run/odhcp6c.pid)\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));
461 // Don't want to pull-in librt and libpthread just for a monotonic clock...
462 uint64_t odhcp6c_get_milli_time(void)
464 struct timespec t = {0, 0};
465 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
466 return t.tv_sec * 1000 + t.tv_nsec / 1000000;
470 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
473 return state_data[state] + state_len[state];
474 else if (state_len[state] + len > 1024)
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;
487 bool odhcp6c_signal_process(void)
492 bool ra_updated = ra_process();
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);
507 return signal_usr1 || signal_usr2 || signal_term;
511 void odhcp6c_clear_state(enum odhcp6c_state state)
513 state_len[state] = 0;
517 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
519 uint8_t *n = odhcp6c_resize_state(state, len);
521 memcpy(n, data, len);
524 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len)
526 ssize_t len_after = state_len[state] - offset;
530 uint8_t *n = odhcp6c_resize_state(state, len);
532 uint8_t *sdata = state_data[state];
534 memmove(sdata + offset + len, sdata + offset, len_after);
535 memcpy(sdata + offset, data, len);
539 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
541 uint8_t *data = state_data[state];
542 ssize_t len_after = state_len[state] - (offset + len);
544 return state_len[state];
546 memmove(data + offset, data + offset + len, len_after);
547 return state_len[state] -= len;
551 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len)
553 *len = state_len[state];
554 void *data = state_data[state];
556 state_len[state] = 0;
557 state_data[state] = NULL;
563 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
565 *len = state_len[state];
566 return state_data[state];
570 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
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;
576 for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
577 if (!memcmp(c, new, cmplen))
584 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
587 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
588 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
590 if (x && x->valid > new->valid && new->valid < safe)
593 if (new->valid > 0) {
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)
602 x->valid = new->valid;
603 x->preferred = new->preferred;
606 x->class = new->class;
609 odhcp6c_add_state(state, new, sizeof(*new));
612 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
618 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
620 return odhcp6c_update_entry_safe(state, new, 0);
624 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
627 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
628 for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
631 else if (c->t1 != UINT32_MAX)
636 else if (c->t2 != UINT32_MAX)
639 if (c->preferred < elapsed)
641 else if (c->preferred != UINT32_MAX)
642 c->preferred -= elapsed;
644 if (c->valid < elapsed)
646 else if (c->valid != UINT32_MAX)
650 odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
655 void odhcp6c_expire(void)
657 time_t now = odhcp6c_get_milli_time() / 1000;
658 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
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);
669 uint32_t odhcp6c_elapsed(void)
671 return odhcp6c_get_milli_time() / 1000 - last_update;
675 void odhcp6c_random(void *buf, size_t len)
677 read(urandom_fd, buf, len);
680 bool odhcp6c_is_bound(void)
685 static void sighandler(int signal)
687 if (signal == SIGCHLD)
688 while (waitpid(-1, NULL, WNOHANG) > 0);
689 else if (signal == SIGUSR1)
691 else if (signal == SIGUSR2)
693 else if (signal == SIGIO)