2 * Copyright (C) 2012-2013 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;
56 int main(_unused int argc, char* const argv[])
58 // Allocate ressources
59 const char *pidfile = NULL;
60 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_TRY;
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;
76 int c, request_pd = 0;
77 while ((c = getopt(argc, argv, "S::N:P:FB:c:i:r:s:kt:hedp:")) != -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 if (allow_slaac_only >= 0 && allow_slaac_only < 10)
98 allow_slaac_only = 10;
100 request_pd = strtoul(optarg, NULL, 10);
107 allow_slaac_only = -1;
108 ia_pd_mode = IA_MODE_FORCE;
113 bfd_interval = atoi(optarg);
118 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
121 buf[1] = DHCPV6_OPT_CLIENTID;
124 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
131 if (inet_pton(AF_INET6, optarg, &ifid) != 1)
138 opttype = htons(strtoul(optarg, &optpos, 10));
139 if (optpos == optarg)
143 odhcp6c_add_state(STATE_ORO, &opttype, 2);
156 sol_timeout = atoi(optarg);
160 logopt |= LOG_PERROR;
177 openlog("odhcp6c", logopt, LOG_DAEMON);
178 const char *ifname = argv[optind];
183 signal(SIGIO, sighandler);
184 signal(SIGHUP, sighandler);
185 signal(SIGINT, sighandler);
186 signal(SIGCHLD, sighandler);
187 signal(SIGTERM, sighandler);
188 signal(SIGUSR1, sighandler);
189 signal(SIGUSR2, sighandler);
191 if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
192 init_dhcpv6(ifname, request_pd, sol_timeout) ||
193 ra_init(ifname, &ifid) || script_init(script, ifname)) {
194 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
199 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
201 syslog(LOG_ERR, "Failed to daemonize: %s",
208 snprintf(pidbuf, sizeof(pidbuf),
209 "/var/run/odhcp6c.%s.pid", ifname);
213 int fd = open(pidfile, O_WRONLY | O_CREAT);
216 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
222 script_call("started");
224 while (!signal_term) { // Main logic
225 odhcp6c_clear_state(STATE_SERVER_ID);
226 odhcp6c_clear_state(STATE_IA_NA);
227 odhcp6c_clear_state(STATE_IA_PD);
228 odhcp6c_clear_state(STATE_SNTP_IP);
229 odhcp6c_clear_state(STATE_SNTP_FQDN);
230 odhcp6c_clear_state(STATE_SIP_IP);
231 odhcp6c_clear_state(STATE_SIP_FQDN);
232 dhcpv6_set_ia_mode(ia_na_mode, ia_pd_mode);
235 syslog(LOG_NOTICE, "(re)starting transaction on %s", ifname);
237 signal_usr1 = signal_usr2 = false;
238 int mode = dhcpv6_request(DHCPV6_MSG_SOLICIT);
239 odhcp6c_signal_process();
245 int res = dhcpv6_request(mode == DHCPV6_STATELESS ?
246 DHCPV6_MSG_INFO_REQ : DHCPV6_MSG_REQUEST);
247 bool signalled = odhcp6c_signal_process();
251 else if (signalled) {
256 mode = dhcpv6_promote_server_cand();
257 } while (mode > DHCPV6_UNKNOWN);
263 case DHCPV6_STATELESS:
265 syslog(LOG_NOTICE, "entering stateless-mode on %s", ifname);
267 while (!signal_usr2 && !signal_term) {
269 script_call("informed");
271 int res = dhcpv6_poll_reconfigure();
272 odhcp6c_signal_process();
278 signal_usr1 = false; // Acknowledged
281 if (signal_usr2 || signal_term)
284 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
285 odhcp6c_signal_process();
293 case DHCPV6_STATEFUL:
294 script_call("bound");
296 syslog(LOG_NOTICE, "entering stateful-mode on %s", ifname);
298 if (bfd_interval > 0)
299 bfd_start(ifname, bfd_loss, bfd_interval);
302 while (!signal_usr2 && !signal_term) {
304 // Wait for T1 to expire or until we get a reconfigure
305 int res = dhcpv6_poll_reconfigure();
306 odhcp6c_signal_process();
308 script_call("updated");
312 // Handle signal, if necessary
314 signal_usr1 = false; // Acknowledged
315 if (signal_usr2 || signal_term)
316 break; // Other signal type
318 // Send renew as T1 expired
319 size_t ia_pd_len, ia_na_len;
320 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
321 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
323 // If we have any IAs, send renew, otherwise request
324 if (ia_pd_len == 0 && ia_na_len == 0)
325 res = dhcpv6_request(DHCPV6_MSG_REQUEST);
327 res = dhcpv6_request(DHCPV6_MSG_RENEW);
329 odhcp6c_signal_process();
330 if (res > 0) { // Renew was succesfull
332 script_call("updated");
333 continue; // Renew was successful
336 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
338 // If we have IAs, try rebind otherwise restart
339 res = dhcpv6_request(DHCPV6_MSG_REBIND);
340 odhcp6c_signal_process();
343 script_call("rebound");
357 size_t ia_pd_len, ia_na_len, server_id_len;
358 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
359 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
360 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
362 // Add all prefixes to lost prefixes
364 script_call("unbound");
366 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0) && release)
367 dhcpv6_request(DHCPV6_MSG_RELEASE);
369 odhcp6c_clear_state(STATE_IA_NA);
370 odhcp6c_clear_state(STATE_IA_PD);
373 script_call("stopped");
378 static int usage(void)
381 "Usage: odhcp6c [options] <interface>\n"
382 "\nFeature options:\n"
383 " -S <time> Wait at least <time> sec for a DHCP-server (0)\n"
384 " -N <mode> Mode for requesting addresses [try|force|none]\n"
385 " -P <length> Request IPv6-Prefix (0 = auto)\n"
386 " -F Force IPv6-Prefix\n"
388 " -B <interval> Enable BFD ping check\n"
390 " -c <clientid> Override client-ID (base-16 encoded)\n"
391 " -i <iface-id> Use a custom interface identifier for RA handling\n"
392 " -r <options> Options to be requested (comma-separated)\n"
393 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
394 " -k Don't send a RELEASE when stopping\n"
395 " -t <seconds> Maximum timeout for DHCPv6-SOLICIT (120)\n"
396 "\nInvocation options:\n"
397 " -p <pidfile> Set pidfile (/var/run/6relayd.pid)\n"
399 " -e Write logmessages to stderr\n"
400 //" -v Increase logging verbosity\n"
401 " -h Show this help\n\n";
402 write(STDERR_FILENO, buf, sizeof(buf));
407 // Don't want to pull-in librt and libpthread just for a monotonic clock...
408 uint64_t odhcp6c_get_milli_time(void)
410 struct timespec t = {0, 0};
411 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
412 return t.tv_sec * 1000 + t.tv_nsec / 1000000;
416 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
419 return state_data[state] + state_len[state];
420 else if (state_len[state] + len > 1024)
423 uint8_t *n = realloc(state_data[state], state_len[state] + len);
424 if (n || state_len[state] + len == 0) {
425 state_data[state] = n;
426 n += state_len[state];
427 state_len[state] += len;
433 bool odhcp6c_signal_process(void)
438 bool ra_updated = ra_process();
443 if (ra_updated && (bound || allow_slaac_only == 0))
444 script_call("ra-updated"); // Immediate process urgent events
445 else if (ra_updated && !bound && allow_slaac_only > 0)
446 script_delay_call("ra-updated", allow_slaac_only);
453 return signal_usr1 || signal_usr2 || signal_term;
457 void odhcp6c_clear_state(enum odhcp6c_state state)
459 state_len[state] = 0;
463 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
465 uint8_t *n = odhcp6c_resize_state(state, len);
467 memcpy(n, data, len);
470 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len)
472 ssize_t len_after = state_len[state] - offset;
476 uint8_t *n = odhcp6c_resize_state(state, len);
478 uint8_t *sdata = state_data[state];
480 memmove(sdata + offset + len, sdata + offset, len_after);
481 memcpy(sdata + offset, data, len);
485 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
487 uint8_t *data = state_data[state];
488 ssize_t len_after = state_len[state] - (offset + len);
490 return state_len[state];
492 memmove(data + offset, data + offset + len, len_after);
493 return state_len[state] -= len;
497 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len)
499 *len = state_len[state];
500 void *data = state_data[state];
502 state_len[state] = 0;
503 state_data[state] = NULL;
509 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
511 *len = state_len[state];
512 return state_data[state];
516 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
518 size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
519 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
520 struct odhcp6c_entry *x = NULL;
522 for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
523 if (!memcmp(c, new, cmplen))
530 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
533 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
534 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
536 if (x && x->valid > new->valid && new->valid < safe)
539 if (new->valid > 0) {
541 if (new->valid >= x->valid && new->valid - x->valid < 60 &&
542 new->preferred >= x->preferred &&
543 new->preferred - x->preferred < 60 &&
544 x->class == new->class)
546 x->valid = new->valid;
547 x->preferred = new->preferred;
550 x->class = new->class;
552 odhcp6c_add_state(state, new, sizeof(*new));
555 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
561 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
563 return odhcp6c_update_entry_safe(state, new, 0);
567 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
570 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
571 for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
574 else if (c->t1 != UINT32_MAX)
579 else if (c->t2 != UINT32_MAX)
582 if (c->preferred < elapsed)
584 else if (c->preferred != UINT32_MAX)
585 c->preferred -= elapsed;
587 if (c->valid < elapsed)
589 else if (c->valid != UINT32_MAX)
593 odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
598 void odhcp6c_expire(void)
600 time_t now = odhcp6c_get_milli_time() / 1000;
601 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
604 odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
605 odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
606 odhcp6c_expire_list(STATE_RA_DNS, elapsed);
607 odhcp6c_expire_list(STATE_IA_NA, elapsed);
608 odhcp6c_expire_list(STATE_IA_PD, elapsed);
612 uint32_t odhcp6c_elapsed(void)
614 return odhcp6c_get_milli_time() / 1000 - last_update;
618 void odhcp6c_random(void *buf, size_t len)
620 read(urandom_fd, buf, len);
623 bool odhcp6c_is_bound(void)
628 static void sighandler(int signal)
630 if (signal == SIGCHLD)
631 while (waitpid(-1, NULL, WNOHANG) > 0);
632 else if (signal == SIGUSR1)
634 else if (signal == SIGUSR2)
636 else if (signal == SIGIO)