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>
37 static void sighandler(int signal);
38 static int usage(void);
40 static uint8_t *state_data[_STATE_MAX] = {NULL};
41 static size_t state_len[_STATE_MAX] = {0};
43 static volatile bool signal_io = false;
44 static volatile bool signal_usr1 = false;
45 static volatile bool signal_usr2 = false;
46 static volatile bool signal_term = false;
48 static int urandom_fd = -1, allow_slaac_only = 0;
49 static bool bound = false, release = true;
50 static time_t last_update = 0;
52 static unsigned int min_update_interval = DEFAULT_MIN_UPDATE_INTERVAL;
54 int main(_unused int argc, char* const argv[])
56 // Allocate ressources
57 const char *pidfile = NULL;
58 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;
72 bool help = false, daemonize = false;
75 unsigned int client_options = DHCPV6_CLIENT_FQDN | DHCPV6_ACCEPT_RECONFIGURE;
77 while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:s:kt:m:hedp:fav")) != -1) {
80 allow_slaac_only = (optarg) ? atoi(optarg) : -1;
84 if (!strcmp(optarg, "force")) {
85 ia_na_mode = IA_MODE_FORCE;
86 allow_slaac_only = -1;
87 } else if (!strcmp(optarg, "none")) {
88 ia_na_mode = IA_MODE_NONE;
89 } else if (!strcmp(optarg, "try")) {
90 ia_na_mode = IA_MODE_TRY;
97 l = script_unhexlify(buf, sizeof(buf), optarg);
101 odhcp6c_add_state(STATE_VENDORCLASS, buf, l);
105 if (ia_pd_mode == IA_MODE_NONE)
106 ia_pd_mode = IA_MODE_TRY;
108 if (allow_slaac_only >= 0 && allow_slaac_only < 10)
109 allow_slaac_only = 10;
114 int prefix_length = strtoul(optarg, &iaid_begin, 10);
116 if (*iaid_begin != '\0' && *iaid_begin != ',' && *iaid_begin != ':') {
117 syslog(LOG_ERR, "invalid argument: '%s'", optarg);
121 struct odhcp6c_request_prefix prefix = { 0, prefix_length };
123 if (*iaid_begin == ',' && (iaid_len = strlen(iaid_begin)) > 1)
124 memcpy(&prefix.iaid, iaid_begin + 1, iaid_len > 4 ? 4 : iaid_len);
125 else if (*iaid_begin == ':')
126 prefix.iaid = htonl((uint32_t)strtoul(&iaid_begin[1], NULL, 16));
128 prefix.iaid = htonl(++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;
140 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
143 buf[1] = DHCPV6_OPT_CLIENTID;
146 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
153 if (inet_pton(AF_INET6, optarg, &ifid) != 1)
160 opttype = htons(strtoul(optarg, &optpos, 10));
161 if (optpos == optarg)
165 odhcp6c_add_state(STATE_ORO, &opttype, 2);
170 client_options |= DHCPV6_STRICT_OPTIONS;
174 optlen = htons(strlen(optarg));
175 odhcp6c_add_state(STATE_USERCLASS, &optlen, 2);
176 odhcp6c_add_state(STATE_USERCLASS, optarg, strlen(optarg));
188 sol_timeout = atoi(optarg);
192 min_update_interval = atoi(optarg);
196 logopt |= LOG_PERROR;
208 client_options &= ~DHCPV6_CLIENT_FQDN;
212 client_options &= ~DHCPV6_ACCEPT_RECONFIGURE;
225 openlog("odhcp6c", logopt, LOG_DAEMON);
227 setlogmask(LOG_UPTO(LOG_WARNING));
229 const char *ifname = argv[optind];
234 signal(SIGIO, sighandler);
235 signal(SIGHUP, sighandler);
236 signal(SIGINT, sighandler);
237 signal(SIGCHLD, sighandler);
238 signal(SIGTERM, sighandler);
239 signal(SIGUSR1, sighandler);
240 signal(SIGUSR2, sighandler);
242 if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
243 init_dhcpv6(ifname, client_options, sol_timeout) ||
244 ra_init(ifname, &ifid) || script_init(script, ifname)) {
245 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
250 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
252 syslog(LOG_ERR, "Failed to daemonize: %s",
258 snprintf((char*)buf, sizeof(buf), "/var/run/odhcp6c.%s.pid", ifname);
259 pidfile = (char*)buf;
262 FILE *fp = fopen(pidfile, "w");
264 fprintf(fp, "%i\n", getpid());
269 script_call("started");
271 while (!signal_term) { // Main logic
272 odhcp6c_clear_state(STATE_SERVER_ID);
273 odhcp6c_clear_state(STATE_SERVER_ADDR);
274 odhcp6c_clear_state(STATE_IA_NA);
275 odhcp6c_clear_state(STATE_IA_PD);
276 odhcp6c_clear_state(STATE_SNTP_IP);
277 odhcp6c_clear_state(STATE_NTP_IP);
278 odhcp6c_clear_state(STATE_NTP_FQDN);
279 odhcp6c_clear_state(STATE_SIP_IP);
280 odhcp6c_clear_state(STATE_SIP_FQDN);
283 syslog(LOG_NOTICE, "(re)starting transaction on %s", ifname);
285 signal_usr1 = signal_usr2 = false;
286 int mode = dhcpv6_set_ia_mode(ia_na_mode, ia_pd_mode);
287 if (mode != DHCPV6_STATELESS)
288 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:
345 script_call("bound");
346 syslog(LOG_NOTICE, "entering stateful-mode on %s", ifname);
348 while (!signal_usr2 && !signal_term) {
350 // Wait for T1 to expire or until we get a reconfigure
351 int res = dhcpv6_poll_reconfigure();
352 odhcp6c_signal_process();
354 script_call("updated");
358 // Handle signal, if necessary
360 signal_usr1 = false; // Acknowledged
361 if (signal_usr2 || signal_term)
362 break; // Other signal type
364 // Send renew as T1 expired
365 res = dhcpv6_request(DHCPV6_MSG_RENEW);
366 odhcp6c_signal_process();
367 if (res > 0) { // Renew was succesfull
369 script_call("updated");
370 continue; // Renew was successful
373 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
374 odhcp6c_clear_state(STATE_SERVER_ADDR);
376 size_t ia_pd_len, ia_na_len;
377 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
378 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
380 if (ia_pd_len == 0 && ia_na_len == 0)
383 // If we have IAs, try rebind otherwise restart
384 res = dhcpv6_request(DHCPV6_MSG_REBIND);
385 odhcp6c_signal_process();
388 script_call("rebound");
401 size_t ia_pd_len, ia_na_len, server_id_len;
402 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
403 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
404 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
406 // Add all prefixes to lost prefixes
408 script_call("unbound");
410 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0) && release)
411 dhcpv6_request(DHCPV6_MSG_RELEASE);
413 odhcp6c_clear_state(STATE_IA_NA);
414 odhcp6c_clear_state(STATE_IA_PD);
417 script_call("stopped");
422 static int usage(void)
425 "Usage: odhcp6c [options] <interface>\n"
426 "\nFeature options:\n"
427 " -S <time> Wait at least <time> sec for a DHCP-server (0)\n"
428 " -N <mode> Mode for requesting addresses [try|force|none]\n"
429 " -P <length> Request IPv6-Prefix (0 = auto)\n"
430 " -F Force IPv6-Prefix\n"
431 " -V <class> Set vendor-class option (base-16 encoded)\n"
432 " -u <user-class> Set user-class option string\n"
433 " -c <clientid> Override client-ID (base-16 encoded 16-bit type + value)\n"
434 " -i <iface-id> Use a custom interface identifier for RA handling\n"
435 " -r <options> Options to be requested (comma-separated)\n"
436 " -R Do not request any options except those specified with -r\n"
437 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
438 " -a Don't send Accept Reconfigure option\n"
439 " -f Don't send Client FQDN option\n"
440 " -k Don't send a RELEASE when stopping\n"
441 " -t <seconds> Maximum timeout for DHCPv6-SOLICIT (120)\n"
442 " -m <seconds> Minimum time between accepting updates (30)\n"
443 "\nInvocation options:\n"
444 " -p <pidfile> Set pidfile (/var/run/odhcp6c.pid)\n"
446 " -e Write logmessages to stderr\n"
447 " -v Increase logging verbosity\n"
448 " -h Show this help\n\n";
454 // Don't want to pull-in librt and libpthread just for a monotonic clock...
455 uint64_t odhcp6c_get_milli_time(void)
457 struct timespec t = {0, 0};
458 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
459 return ((uint64_t)t.tv_sec) * 1000 + ((uint64_t)t.tv_nsec) / 1000000;
463 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
466 return state_data[state] + state_len[state];
467 else if (state_len[state] + len > 1024)
470 uint8_t *n = realloc(state_data[state], state_len[state] + len);
471 if (n || state_len[state] + len == 0) {
472 state_data[state] = n;
473 n += state_len[state];
474 state_len[state] += len;
480 bool odhcp6c_signal_process(void)
485 bool ra_updated = ra_process();
490 if (ra_updated && (bound || allow_slaac_only >= 0))
491 script_call("ra-updated"); // Immediate process urgent events
494 return signal_usr1 || signal_usr2 || signal_term;
498 void odhcp6c_clear_state(enum odhcp6c_state state)
500 state_len[state] = 0;
504 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
506 uint8_t *n = odhcp6c_resize_state(state, len);
508 memcpy(n, data, len);
511 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len)
513 ssize_t len_after = state_len[state] - offset;
517 uint8_t *n = odhcp6c_resize_state(state, len);
519 uint8_t *sdata = state_data[state];
521 memmove(sdata + offset + len, sdata + offset, len_after);
522 memcpy(sdata + offset, data, len);
526 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
528 uint8_t *data = state_data[state];
529 ssize_t len_after = state_len[state] - (offset + len);
531 return state_len[state];
533 memmove(data + offset, data + offset + len, len_after);
534 return state_len[state] -= len;
538 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len)
540 *len = state_len[state];
541 void *data = state_data[state];
543 state_len[state] = 0;
544 state_data[state] = NULL;
550 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
552 *len = state_len[state];
553 return state_data[state];
557 static struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
559 size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + ((new->length + 7) / 8);
560 uint8_t *start = odhcp6c_get_state(state, &len);
562 for (struct odhcp6c_entry *c = (struct odhcp6c_entry*)start;
563 (uint8_t*)c < &start[len] && &c->auxtarget[c->auxlen] <= &start[len];
564 c = (struct odhcp6c_entry*)(&c->auxtarget[c->auxlen]))
565 if (!memcmp(c, new, cmplen) && !memcmp(c->auxtarget, new->auxtarget, new->auxlen))
572 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new,
573 uint32_t safe, bool filterexcess)
576 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
577 uint8_t *start = odhcp6c_get_state(state, &len);
579 if (x && x->valid > new->valid && new->valid < safe)
582 if (new->valid > 0) {
584 if (filterexcess && new->valid >= x->valid &&
585 new->valid != UINT32_MAX &&
586 new->valid - x->valid < min_update_interval &&
587 new->preferred >= x->preferred &&
588 new->preferred != UINT32_MAX &&
589 new->preferred - x->preferred < min_update_interval)
591 x->valid = new->valid;
592 x->preferred = new->preferred;
597 odhcp6c_add_state(state, new, sizeof(*new) + new->auxlen);
600 odhcp6c_remove_state(state, ((uint8_t*)x) - start, sizeof(*x) + x->auxlen);
606 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
609 uint8_t *start = odhcp6c_get_state(state, &len);
610 for (struct odhcp6c_entry *c = (struct odhcp6c_entry*)start;
611 (uint8_t*)c < &start[len] && &c->auxtarget[c->auxlen] <= &start[len];
612 c = (struct odhcp6c_entry*)(&c->auxtarget[c->auxlen])) {
615 else if (c->t1 != UINT32_MAX)
620 else if (c->t2 != UINT32_MAX)
623 if (c->preferred < elapsed)
625 else if (c->preferred != UINT32_MAX)
626 c->preferred -= elapsed;
628 if (c->valid < elapsed)
630 else if (c->valid != UINT32_MAX)
634 odhcp6c_remove_state(state, ((uint8_t*)c) - start, sizeof(*c) + c->auxlen);
639 void odhcp6c_expire(void)
641 time_t now = odhcp6c_get_milli_time() / 1000;
642 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
645 odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
646 odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
647 odhcp6c_expire_list(STATE_RA_DNS, elapsed);
648 odhcp6c_expire_list(STATE_RA_SEARCH, elapsed);
649 odhcp6c_expire_list(STATE_IA_NA, elapsed);
650 odhcp6c_expire_list(STATE_IA_PD, elapsed);
654 uint32_t odhcp6c_elapsed(void)
656 return odhcp6c_get_milli_time() / 1000 - last_update;
660 int odhcp6c_random(void *buf, size_t len)
662 return read(urandom_fd, buf, len);
665 bool odhcp6c_is_bound(void)
670 static void sighandler(int signal)
672 if (signal == SIGCHLD)
673 while (waitpid(-1, NULL, WNOHANG) > 0);
674 else if (signal == SIGUSR1)
676 else if (signal == SIGUSR2)
678 else if (signal == SIGIO)