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 = true;
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 = false;
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 allow_slaac_only = false;
81 request_pd = strtoul(optarg, NULL, 10);
87 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
90 buf[1] = DHCPV6_OPT_CLIENTID;
93 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
102 opttype = htons(strtoul(optarg, &optpos, 10));
103 if (optpos == optarg)
107 odhcp6c_add_state(STATE_ORO, &opttype, 2);
129 const char *ifname = argv[optind];
134 if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
135 init_dhcpv6(ifname, request_pd) || ra_init(ifname) ||
136 script_init(script, ifname)) {
137 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
141 signal(SIGIO, sighandler);
142 signal(SIGHUP, sighandler);
143 signal(SIGINT, sighandler);
144 signal(SIGCHLD, sighandler);
145 signal(SIGTERM, sighandler);
146 signal(SIGUSR1, sighandler);
147 signal(SIGUSR2, sighandler);
150 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
152 syslog(LOG_ERR, "Failed to daemonize: %s",
159 snprintf(pidbuf, sizeof(pidbuf),
160 "/var/run/odhcp6c.%s.pid", ifname);
164 int fd = open(pidfile, O_WRONLY | O_CREAT);
167 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
173 script_call("started");
175 while (do_signal != SIGTERM) { // Main logic
176 odhcp6c_clear_state(STATE_SERVER_ID);
177 odhcp6c_clear_state(STATE_SERVER_CAND);
178 odhcp6c_clear_state(STATE_IA_PD);
179 odhcp6c_clear_state(STATE_SNTP_IP);
180 odhcp6c_clear_state(STATE_SNTP_FQDN);
181 odhcp6c_clear_state(STATE_SIP_IP);
182 odhcp6c_clear_state(STATE_SIP_FQDN);
183 dhcpv6_set_ia_na_mode(ia_na_mode);
187 int res = dhcpv6_request(DHCPV6_MSG_SOLICIT);
188 odhcp6c_signal_process();
191 continue; // Might happen if we got a signal
192 } else if (res == DHCPV6_STATELESS) { // Stateless mode
193 while (do_signal == 0 || do_signal == SIGUSR1) {
196 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
197 odhcp6c_signal_process();
198 if (do_signal == SIGUSR1)
203 script_call("informed");
207 if (dhcpv6_poll_reconfigure() > 0)
208 script_call("informed");
215 if (dhcpv6_request(DHCPV6_MSG_REQUEST) < 0)
218 odhcp6c_signal_process();
219 script_call("bound");
222 while (do_signal == 0 || do_signal == SIGUSR1) {
224 // Wait for T1 to expire or until we get a reconfigure
225 int res = dhcpv6_poll_reconfigure();
226 odhcp6c_signal_process();
229 script_call("updated");
234 // Handle signal, if necessary
235 if (do_signal == SIGUSR1)
236 do_signal = 0; // Acknowledged
237 else if (do_signal > 0)
238 break; // Other signal type
240 size_t ia_pd_len, ia_na_len, ia_pd_new, ia_na_new;
241 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
242 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
244 // If we have any IAs, send renew, otherwise request
246 if (ia_pd_len == 0 && ia_na_len == 0)
247 r = dhcpv6_request(DHCPV6_MSG_REQUEST);
249 r = dhcpv6_request(DHCPV6_MSG_RENEW);
250 odhcp6c_signal_process();
251 if (r > 0) // Publish updates
252 script_call("updated");
254 continue; // Renew was successful
256 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
258 // If we have IAs, try rebind otherwise restart
259 res = dhcpv6_request(DHCPV6_MSG_REBIND);
260 odhcp6c_signal_process();
262 odhcp6c_get_state(STATE_IA_PD, &ia_pd_new);
263 odhcp6c_get_state(STATE_IA_NA, &ia_na_new);
264 if (res < 0 || (ia_pd_new == 0 && ia_pd_len) ||
265 (ia_na_new == 0 && ia_na_len))
266 break; // We lost all our IAs, restart
268 script_call("rebound");
272 size_t ia_pd_len, ia_na_len, server_id_len;
273 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
274 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
275 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
277 // Add all prefixes to lost prefixes
279 script_call("unbound");
281 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0))
282 dhcpv6_request(DHCPV6_MSG_RELEASE);
284 odhcp6c_clear_state(STATE_IA_NA);
285 odhcp6c_clear_state(STATE_IA_PD);
288 script_call("stopped");
293 static int usage(void)
296 "Usage: odhcp6c [options] <interface>\n"
297 "\nFeature options:\n"
298 " -S Don't allow SLAAC-only (implied by -P)\n"
299 " -N <mode> Mode for requesting addresses [try|force|none]\n"
300 " -P <length> Request IPv6-Prefix (0 = auto)\n"
301 " -c <clientid> Override client-ID (base-16 encoded)\n"
302 " -r <options> Options to be requested (comma-separated)\n"
303 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
304 "\nInvocation options:\n"
305 " -p <pidfile> Set pidfile (/var/run/6relayd.pid)\n"
307 //" -v Increase logging verbosity\n"
308 " -h Show this help\n\n";
309 write(STDERR_FILENO, buf, sizeof(buf));
314 // Don't want to pull-in librt and libpthread just for a monotonic clock...
315 uint64_t odhcp6c_get_milli_time(void)
317 struct timespec t = {0, 0};
318 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
319 return t.tv_sec * 1000 + t.tv_nsec / 1000000;
323 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
326 return state_data[state] + state_len[state];
327 else if (state_len[state] + len > 1024)
330 uint8_t *n = realloc(state_data[state], state_len[state] + len);
331 if (n || state_len[state] + len == 0) {
332 state_data[state] = n;
333 n += state_len[state];
334 state_len[state] += len;
340 bool odhcp6c_signal_process(void)
342 if (do_signal == SIGIO) {
344 bool updated = ra_process();
345 updated |= ra_rtnl_process();
346 if (updated && (bound || allow_slaac_only)) {
348 script_call("ra-updated");
352 return do_signal != 0;
356 void odhcp6c_clear_state(enum odhcp6c_state state)
358 state_len[state] = 0;
362 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
364 uint8_t *n = odhcp6c_resize_state(state, len);
366 memcpy(n, data, len);
370 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
372 uint8_t *data = state_data[state];
373 ssize_t len_after = state_len[state] - (offset + len);
375 return state_len[state];
377 memmove(data + offset, data + offset + len, len_after);
378 return state_len[state] -= len;
382 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
384 *len = state_len[state];
385 return state_data[state];
389 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
391 size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
392 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
393 struct odhcp6c_entry *x = NULL;
395 for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
396 if (!memcmp(c, new, cmplen))
403 void odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
406 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
407 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
409 if (x && x->valid > new->valid && new->valid < safe)
412 if (new->valid > 0) {
414 x->valid = new->valid;
415 x->preferred = new->preferred;
417 odhcp6c_add_state(state, new, sizeof(*new));
420 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
425 void odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
427 odhcp6c_update_entry_safe(state, new, 0);
431 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
434 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
435 for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
436 if (c->preferred < elapsed)
438 else if (c->preferred != UINT32_MAX)
439 c->preferred -= elapsed;
441 if (c->valid < elapsed)
443 else if (c->valid != UINT32_MAX)
447 odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
452 void odhcp6c_expire(void)
454 static time_t last_update = 0;
455 time_t now = odhcp6c_get_milli_time() / 1000;
457 uint32_t elapsed = now - last_update;
460 odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
461 odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
462 odhcp6c_expire_list(STATE_RA_DNS, elapsed);
463 odhcp6c_expire_list(STATE_IA_NA, elapsed);
464 odhcp6c_expire_list(STATE_IA_PD, elapsed);
468 void odhcp6c_random(void *buf, size_t len)
470 read(urandom_fd, buf, len);
474 static void sighandler(int signal)
476 if (signal == SIGCHLD)
477 while (waitpid(-1, NULL, WNOHANG) > 0);
478 else if (signal == SIGUSR1)
480 else if (signal == SIGUSR2)
482 else if (signal == SIGIO)