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 int do_signal = 0;
47 static int urandom_fd = -1, allow_slaac_only = 0;
48 static bool bound = false, release = true;
49 static time_t last_update = 0;
52 int main(_unused int argc, char* const argv[])
54 // Allocate ressources
55 const char *pidfile = NULL;
56 const char *script = "/usr/sbin/odhcp6c-update";
61 enum odhcp6c_ia_mode ia_na_mode = IA_MODE_TRY;
62 enum odhcp6c_ia_mode ia_pd_mode = IA_MODE_TRY;
63 static struct in6_addr ifid = IN6ADDR_ANY_INIT;
64 int sol_timeout = 120;
66 bool help = false, daemonize = false;
68 int c, request_pd = 0;
69 while ((c = getopt(argc, argv, "S::N:P:Fc:i:r:s:kt:hedp:")) != -1) {
72 allow_slaac_only = (optarg) ? atoi(optarg) : -1;
76 if (!strcmp(optarg, "force")) {
77 ia_na_mode = IA_MODE_FORCE;
78 allow_slaac_only = -1;
79 } else if (!strcmp(optarg, "none")) {
80 ia_na_mode = IA_MODE_NONE;
81 } else if (!strcmp(optarg, "try")) {
82 ia_na_mode = IA_MODE_TRY;
89 if (allow_slaac_only >= 0 && allow_slaac_only < 10)
90 allow_slaac_only = 10;
92 request_pd = strtoul(optarg, NULL, 10);
99 allow_slaac_only = -1;
100 ia_pd_mode = IA_MODE_FORCE;
104 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
107 buf[1] = DHCPV6_OPT_CLIENTID;
110 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
117 if (inet_pton(AF_INET6, optarg, &ifid) != 1)
124 opttype = htons(strtoul(optarg, &optpos, 10));
125 if (optpos == optarg)
129 odhcp6c_add_state(STATE_ORO, &opttype, 2);
142 sol_timeout = atoi(optarg);
146 logopt |= LOG_PERROR;
163 openlog("odhcp6c", logopt, LOG_DAEMON);
164 const char *ifname = argv[optind];
169 signal(SIGIO, sighandler);
170 signal(SIGHUP, sighandler);
171 signal(SIGINT, sighandler);
172 signal(SIGCHLD, sighandler);
173 signal(SIGTERM, sighandler);
174 signal(SIGUSR1, sighandler);
175 signal(SIGUSR2, sighandler);
177 if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
178 init_dhcpv6(ifname, request_pd, sol_timeout) ||
179 ra_init(ifname, &ifid) || script_init(script, ifname)) {
180 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
185 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
187 syslog(LOG_ERR, "Failed to daemonize: %s",
194 snprintf(pidbuf, sizeof(pidbuf),
195 "/var/run/odhcp6c.%s.pid", ifname);
199 int fd = open(pidfile, O_WRONLY | O_CREAT);
202 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
208 script_call("started");
210 while (do_signal != SIGTERM) { // Main logic
211 odhcp6c_clear_state(STATE_SERVER_ID);
212 odhcp6c_clear_state(STATE_IA_NA);
213 odhcp6c_clear_state(STATE_IA_PD);
214 odhcp6c_clear_state(STATE_SNTP_IP);
215 odhcp6c_clear_state(STATE_SNTP_FQDN);
216 odhcp6c_clear_state(STATE_SIP_IP);
217 odhcp6c_clear_state(STATE_SIP_FQDN);
218 dhcpv6_set_ia_mode(ia_na_mode, ia_pd_mode);
221 // Server candidates need deep-delete
223 struct dhcpv6_server_cand *cand = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
224 for (size_t i = 0; i < cand_len / sizeof(*cand); ++i) {
228 odhcp6c_clear_state(STATE_SERVER_CAND);
230 syslog(LOG_NOTICE, "(re)starting transaction on %s", ifname);
233 int res = dhcpv6_request(DHCPV6_MSG_SOLICIT);
234 odhcp6c_signal_process();
237 continue; // Might happen if we got a signal
238 } else if (res == DHCPV6_STATELESS) { // Stateless mode
239 while (do_signal == 0 || do_signal == SIGUSR1) {
242 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
243 odhcp6c_signal_process();
244 if (do_signal == SIGUSR1)
249 script_call("informed");
252 syslog(LOG_NOTICE, "entering stateless-mode on %s", ifname);
254 if (dhcpv6_poll_reconfigure() > 0)
255 script_call("informed");
262 if (dhcpv6_request(DHCPV6_MSG_REQUEST) <= 0)
265 odhcp6c_signal_process();
266 script_call("bound");
268 syslog(LOG_NOTICE, "entering stateful-mode on %s", ifname);
270 bfd_start(ifname, 3, 10);
273 while (do_signal == 0 || do_signal == SIGUSR1) {
275 // Wait for T1 to expire or until we get a reconfigure
276 int res = dhcpv6_poll_reconfigure();
277 odhcp6c_signal_process();
279 script_call("updated");
283 // Handle signal, if necessary
284 if (do_signal == SIGUSR1)
285 do_signal = 0; // Acknowledged
286 else if (do_signal > 0)
287 break; // Other signal type
289 size_t ia_pd_len, ia_na_len, ia_pd_new, ia_na_new;
290 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
291 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
293 // If we have any IAs, send renew, otherwise request
295 if (ia_pd_len == 0 && ia_na_len == 0)
296 r = dhcpv6_request(DHCPV6_MSG_REQUEST);
298 r = dhcpv6_request(DHCPV6_MSG_RENEW);
299 odhcp6c_signal_process();
300 if (r > 0) { // Renew was succesfull
302 script_call("updated");
303 continue; // Renew was successful
306 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
308 // If we have IAs, try rebind otherwise restart
309 res = dhcpv6_request(DHCPV6_MSG_REBIND);
310 odhcp6c_signal_process();
312 odhcp6c_get_state(STATE_IA_PD, &ia_pd_new);
313 odhcp6c_get_state(STATE_IA_NA, &ia_na_new);
314 if (res <= 0 || (ia_pd_new == 0 && ia_pd_len) ||
315 (ia_na_new == 0 && ia_na_len))
316 break; // We lost all our IAs, restart
318 script_call("rebound");
326 size_t ia_pd_len, ia_na_len, server_id_len;
327 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
328 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
329 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
331 // Add all prefixes to lost prefixes
333 script_call("unbound");
335 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0) && release)
336 dhcpv6_request(DHCPV6_MSG_RELEASE);
338 odhcp6c_clear_state(STATE_IA_NA);
339 odhcp6c_clear_state(STATE_IA_PD);
342 script_call("stopped");
347 static int usage(void)
350 "Usage: odhcp6c [options] <interface>\n"
351 "\nFeature options:\n"
352 " -S <time> Wait at least <time> sec for a DHCP-server (0)\n"
353 " -N <mode> Mode for requesting addresses [try|force|none]\n"
354 " -P <length> Request IPv6-Prefix (0 = auto)\n"
355 " -F Force IPv6-Prefix\n"
356 " -c <clientid> Override client-ID (base-16 encoded)\n"
357 " -i <iface-id> Use a custom interface identifier for RA handling\n"
358 " -r <options> Options to be requested (comma-separated)\n"
359 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
360 " -k Don't send a RELEASE when stopping\n"
361 " -t <seconds> Maximum timeout for DHCPv6-SOLICIT (120)\n"
362 "\nInvocation options:\n"
363 " -p <pidfile> Set pidfile (/var/run/6relayd.pid)\n"
365 " -e Write logmessages to stderr\n"
366 //" -v Increase logging verbosity\n"
367 " -h Show this help\n\n";
368 write(STDERR_FILENO, buf, sizeof(buf));
373 // Don't want to pull-in librt and libpthread just for a monotonic clock...
374 uint64_t odhcp6c_get_milli_time(void)
376 struct timespec t = {0, 0};
377 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
378 return t.tv_sec * 1000 + t.tv_nsec / 1000000;
382 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
385 return state_data[state] + state_len[state];
386 else if (state_len[state] + len > 1024)
389 uint8_t *n = realloc(state_data[state], state_len[state] + len);
390 if (n || state_len[state] + len == 0) {
391 state_data[state] = n;
392 n += state_len[state];
393 state_len[state] += len;
399 bool odhcp6c_signal_process(void)
401 if (do_signal == SIGIO) {
403 bool ra_updated = ra_process();
408 if (ra_updated && (bound || allow_slaac_only == 0))
409 script_call("ra-updated"); // Immediate process urgent events
410 else if (ra_updated && !bound && allow_slaac_only > 0)
411 script_delay_call("ra-updated", allow_slaac_only);
418 return do_signal != 0;
422 void odhcp6c_clear_state(enum odhcp6c_state state)
424 state_len[state] = 0;
428 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
430 uint8_t *n = odhcp6c_resize_state(state, len);
432 memcpy(n, data, len);
436 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
438 uint8_t *data = state_data[state];
439 ssize_t len_after = state_len[state] - (offset + len);
441 return state_len[state];
443 memmove(data + offset, data + offset + len, len_after);
444 return state_len[state] -= len;
448 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len)
450 *len = state_len[state];
451 void *data = state_data[state];
453 state_len[state] = 0;
454 state_data[state] = NULL;
460 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
462 *len = state_len[state];
463 return state_data[state];
467 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
469 size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
470 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
471 struct odhcp6c_entry *x = NULL;
473 for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
474 if (!memcmp(c, new, cmplen))
481 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
484 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
485 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
487 if (x && x->valid > new->valid && new->valid < safe)
490 if (new->valid > 0) {
492 if (new->valid >= x->valid && new->valid - x->valid < 60 &&
493 new->preferred >= x->preferred &&
494 new->preferred - x->preferred < 60 &&
495 x->class == new->class)
497 x->valid = new->valid;
498 x->preferred = new->preferred;
501 x->class = new->class;
503 odhcp6c_add_state(state, new, sizeof(*new));
506 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
512 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
514 return odhcp6c_update_entry_safe(state, new, 0);
518 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
521 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
522 for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
525 else if (c->t1 != UINT32_MAX)
530 else if (c->t2 != UINT32_MAX)
533 if (c->preferred < elapsed)
535 else if (c->preferred != UINT32_MAX)
536 c->preferred -= elapsed;
538 if (c->valid < elapsed)
540 else if (c->valid != UINT32_MAX)
544 odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
549 void odhcp6c_expire(void)
551 time_t now = odhcp6c_get_milli_time() / 1000;
552 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
555 odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
556 odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
557 odhcp6c_expire_list(STATE_RA_DNS, elapsed);
558 odhcp6c_expire_list(STATE_IA_NA, elapsed);
559 odhcp6c_expire_list(STATE_IA_PD, elapsed);
563 uint32_t odhcp6c_elapsed(void)
565 return odhcp6c_get_milli_time() / 1000 - last_update;
569 void odhcp6c_random(void *buf, size_t len)
571 read(urandom_fd, buf, len);
574 bool odhcp6c_is_bound(void)
579 static void sighandler(int signal)
581 if (signal == SIGCHLD)
582 while (waitpid(-1, NULL, WNOHANG) > 0);
583 else if (signal == SIGUSR1)
585 else if (signal == SIGUSR2)
587 else if (signal == SIGIO)