2 * Copyright (C) 2012 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>
35 static void sighandler(int signal);
36 static int usage(void);
39 static uint8_t *state_data[_STATE_MAX] = {NULL};
40 static size_t state_len[_STATE_MAX] = {0};
42 static volatile int do_signal = 0;
43 static int urandom_fd = -1;
44 static bool bound = false, allow_slaac_only = false;
47 int main(_unused int argc, char* const argv[])
49 openlog("odhcp6c", LOG_PERROR | LOG_PID, LOG_DAEMON);
51 // Allocate ressources
52 const char *pidfile = NULL;
53 const char *script = "/usr/sbin/odhcp6c-update";
58 enum odhcp6c_ia_mode ia_na_mode = IA_MODE_TRY;
60 bool help = false, daemonize = false;
61 int c, request_pd = 0;
62 while ((c = getopt(argc, argv, "SN:P:c:r:s:hdp:")) != -1) {
65 allow_slaac_only = true;
69 if (!strcmp(optarg, "force"))
70 ia_na_mode = IA_MODE_FORCE;
71 else if (!strcmp(optarg, "none"))
72 ia_na_mode = IA_MODE_NONE;
73 else if (!strcmp(optarg, "try"))
74 ia_na_mode = IA_MODE_TRY;
80 request_pd = strtoul(optarg, NULL, 10);
86 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
89 buf[1] = DHCPV6_OPT_CLIENTID;
92 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
101 opttype = htons(strtoul(optarg, &optpos, 10));
102 if (optpos == optarg)
106 odhcp6c_add_state(STATE_ORO, &opttype, 2);
128 const char *ifname = argv[optind];
133 if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
134 init_dhcpv6(ifname, request_pd) || ra_init(ifname) ||
135 script_init(script, ifname)) {
136 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
140 signal(SIGIO, sighandler);
141 signal(SIGHUP, sighandler);
142 signal(SIGINT, sighandler);
143 signal(SIGCHLD, sighandler);
144 signal(SIGTERM, sighandler);
145 signal(SIGUSR1, sighandler);
146 signal(SIGUSR2, sighandler);
149 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
151 syslog(LOG_ERR, "Failed to daemonize: %s",
158 snprintf(pidbuf, sizeof(pidbuf),
159 "/var/run/odhcp6c.%s.pid", ifname);
163 int fd = open(pidfile, O_WRONLY | O_CREAT);
166 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
172 script_call("started");
174 while (do_signal != SIGTERM) { // Main logic
175 odhcp6c_clear_state(STATE_SERVER_ID);
176 odhcp6c_clear_state(STATE_SERVER_CAND);
177 odhcp6c_clear_state(STATE_IA_PD);
178 odhcp6c_clear_state(STATE_SNTP_IP);
179 odhcp6c_clear_state(STATE_SNTP_FQDN);
180 odhcp6c_clear_state(STATE_SIP_IP);
181 odhcp6c_clear_state(STATE_SIP_FQDN);
182 dhcpv6_set_ia_na_mode(ia_na_mode);
186 int res = dhcpv6_request(DHCPV6_MSG_SOLICIT);
187 odhcp6c_signal_process();
190 continue; // Might happen if we got a signal
191 } else if (res == DHCPV6_STATELESS) { // Stateless mode
192 while (do_signal == 0 || do_signal == SIGUSR1) {
195 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
196 odhcp6c_signal_process();
197 if (do_signal == SIGUSR1)
202 script_call("informed");
206 if (dhcpv6_poll_reconfigure() > 0)
207 script_call("informed");
214 if (dhcpv6_request(DHCPV6_MSG_REQUEST) < 0)
217 odhcp6c_signal_process();
218 script_call("bound");
221 while (do_signal == 0 || do_signal == SIGUSR1) {
223 // Wait for T1 to expire or until we get a reconfigure
224 int res = dhcpv6_poll_reconfigure();
225 odhcp6c_signal_process();
228 script_call("updated");
233 // Handle signal, if necessary
234 if (do_signal == SIGUSR1)
235 do_signal = 0; // Acknowledged
236 else if (do_signal > 0)
237 break; // Other signal type
239 size_t ia_pd_len, ia_na_len, ia_pd_new, ia_na_new;
240 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
241 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
243 // If we have any IAs, send renew, otherwise request
245 if (ia_pd_len == 0 && ia_na_len == 0)
246 r = dhcpv6_request(DHCPV6_MSG_REQUEST);
248 r = dhcpv6_request(DHCPV6_MSG_RENEW);
249 odhcp6c_signal_process();
250 if (r > 0) // Publish updates
251 script_call("updated");
253 continue; // Renew was successful
255 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
257 // If we have IAs, try rebind otherwise restart
258 res = dhcpv6_request(DHCPV6_MSG_REBIND);
259 odhcp6c_signal_process();
261 odhcp6c_get_state(STATE_IA_PD, &ia_pd_new);
262 odhcp6c_get_state(STATE_IA_NA, &ia_na_new);
263 if (res < 0 || (ia_pd_new == 0 && ia_pd_len) ||
264 (ia_na_new == 0 && ia_na_len))
265 break; // We lost all our IAs, restart
267 script_call("rebound");
271 size_t ia_pd_len, ia_na_len, server_id_len;
272 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
273 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
274 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
276 // Add all prefixes to lost prefixes
278 script_call("unbound");
280 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0))
281 dhcpv6_request(DHCPV6_MSG_RELEASE);
283 odhcp6c_clear_state(STATE_IA_NA);
284 odhcp6c_clear_state(STATE_IA_PD);
287 script_call("stopped");
292 static int usage(void)
295 "Usage: odhcp6c [options] <interface>\n"
296 "\nFeature options:\n"
297 " -S Allow SLAAC-only assignment\n"
298 " -N <mode> Mode for requesting addresses [try|force|none]\n"
299 " -P <length> Request IPv6-Prefix (0 = auto)\n"
300 " -c <clientid> Override client-ID (base-16 encoded)\n"
301 " -r <options> Options to be requested (comma-separated)\n"
302 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
303 "\nInvocation options:\n"
304 " -p <pidfile> Set pidfile (/var/run/6relayd.pid)\n"
306 //" -v Increase logging verbosity\n"
307 " -h Show this help\n\n";
308 write(STDERR_FILENO, buf, sizeof(buf));
313 // Don't want to pull-in librt and libpthread just for a monotonic clock...
314 uint64_t odhcp6c_get_milli_time(void)
316 struct timespec t = {0, 0};
317 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
318 return t.tv_sec * 1000 + t.tv_nsec / 1000000;
322 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
325 return state_data[state] + state_len[state];
326 else if (state_len[state] + len > 1024)
329 uint8_t *n = realloc(state_data[state], state_len[state] + len);
330 if (n || state_len[state] + len == 0) {
331 state_data[state] = n;
332 n += state_len[state];
333 state_len[state] += len;
339 bool odhcp6c_signal_process(void)
341 if (do_signal == SIGIO) {
343 bool updated = ra_process();
344 updated |= ra_rtnl_process();
345 if (updated && (bound || allow_slaac_only)) {
347 script_call("ra-updated");
351 return do_signal != 0;
355 void odhcp6c_clear_state(enum odhcp6c_state state)
357 state_len[state] = 0;
361 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
363 uint8_t *n = odhcp6c_resize_state(state, len);
365 memcpy(n, data, len);
369 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
371 uint8_t *data = state_data[state];
372 ssize_t len_after = state_len[state] - (offset + len);
374 return state_len[state];
376 memmove(data + offset, data + offset + len, len_after);
377 return state_len[state] -= len;
381 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
383 *len = state_len[state];
384 return state_data[state];
388 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
390 size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
391 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
392 struct odhcp6c_entry *x = NULL;
394 for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
395 if (!memcmp(c, new, cmplen))
402 void odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
405 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
406 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
408 if (x && x->valid > new->valid && new->valid < safe)
411 if (new->valid > 0) {
413 x->valid = new->valid;
414 x->preferred = new->preferred;
416 odhcp6c_add_state(state, new, sizeof(*new));
419 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
424 void odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
426 odhcp6c_update_entry_safe(state, new, 0);
430 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
433 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
434 for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
435 if (c->preferred < elapsed)
437 else if (c->preferred != UINT32_MAX)
438 c->preferred -= elapsed;
440 if (c->valid < elapsed)
442 else if (c->valid != UINT32_MAX)
446 odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
451 void odhcp6c_expire(void)
453 static time_t last_update = 0;
454 time_t now = odhcp6c_get_milli_time() / 1000;
456 uint32_t elapsed = now - last_update;
459 odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
460 odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
461 odhcp6c_expire_list(STATE_RA_DNS, elapsed);
462 odhcp6c_expire_list(STATE_IA_NA, elapsed);
463 odhcp6c_expire_list(STATE_IA_PD, elapsed);
467 void odhcp6c_random(void *buf, size_t len)
469 read(urandom_fd, buf, len);
473 static void sighandler(int signal)
475 if (signal == SIGCHLD)
476 while (waitpid(-1, NULL, WNOHANG) > 0);
477 else if (signal == SIGUSR1)
479 else if (signal == SIGUSR2)
481 else if (signal == SIGIO)