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Be less verbose by default and add -v flag
[project/odhcp6c.git] / src / odhcp6c.c
1 /**
2 * Copyright (C) 2012-2014 Steven Barth <steven@midlink.org>
3 *
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.
7 *
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.
12 *
13 */
14
15 #include <time.h>
16 #include <errno.h>
17 #include <fcntl.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <stddef.h>
21 #include <unistd.h>
22 #include <syslog.h>
23 #include <signal.h>
24 #include <string.h>
25 #include <stdbool.h>
26
27 #include <net/if.h>
28 #include <sys/wait.h>
29 #include <sys/syscall.h>
30 #include <arpa/inet.h>
31
32 #include "odhcp6c.h"
33 #include "ra.h"
34
35
36
37 static void sighandler(int signal);
38 static int usage(void);
39
40 static uint8_t *state_data[_STATE_MAX] = {NULL};
41 static size_t state_len[_STATE_MAX] = {0};
42
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;
47
48 static int urandom_fd = -1, allow_slaac_only = 0;
49 static bool bound = false, release = true;
50 static time_t last_update = 0;
51
52 static unsigned int min_update_interval = DEFAULT_MIN_UPDATE_INTERVAL;
53
54 int main(_unused int argc, char* const argv[])
55 {
56 // Allocate ressources
57 const char *pidfile = NULL;
58 const char *script = "/usr/sbin/odhcp6c-update";
59 ssize_t l;
60 uint8_t buf[134];
61 char *optpos;
62 uint16_t opttype;
63 uint16_t optlen;
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;
69 int verbosity = 0;
70
71
72 bool help = false, daemonize = false;
73 int logopt = LOG_PID;
74 int c;
75 unsigned int client_options = DHCPV6_CLIENT_FQDN | DHCPV6_ACCEPT_RECONFIGURE;
76
77 while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:s:kt:m:hedp:fav")) != -1) {
78 switch (c) {
79 case 'S':
80 allow_slaac_only = (optarg) ? atoi(optarg) : -1;
81 break;
82
83 case 'N':
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;
91 } else{
92 help = true;
93 }
94 break;
95
96 case 'V':
97 l = script_unhexlify(buf, sizeof(buf), optarg);
98 if (!l)
99 help=true;
100
101 odhcp6c_add_state(STATE_VENDORCLASS, buf, l);
102
103 break;
104 case 'P':
105 if (ia_pd_mode == IA_MODE_NONE)
106 ia_pd_mode = IA_MODE_TRY;
107
108 if (allow_slaac_only >= 0 && allow_slaac_only < 10)
109 allow_slaac_only = 10;
110
111 char *iaid_begin;
112 int iaid_len = 0;
113
114 int prefix_length = strtoul(optarg, &iaid_begin, 10);
115
116 if (*iaid_begin != '\0' && *iaid_begin != ',' && *iaid_begin != ':') {
117 syslog(LOG_ERR, "invalid argument: '%s'", optarg);
118 return 1;
119 }
120
121 struct odhcp6c_request_prefix prefix = { 0, prefix_length };
122
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));
127 else
128 prefix.iaid = htonl(++ia_pd_iaid_index);
129
130 odhcp6c_add_state(STATE_IA_PD_INIT, &prefix, sizeof(prefix));
131
132 break;
133
134 case 'F':
135 allow_slaac_only = -1;
136 ia_pd_mode = IA_MODE_FORCE;
137 break;
138
139 case 'c':
140 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
141 if (l > 0) {
142 buf[0] = 0;
143 buf[1] = DHCPV6_OPT_CLIENTID;
144 buf[2] = 0;
145 buf[3] = l;
146 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
147 } else {
148 help = true;
149 }
150 break;
151
152 case 'i':
153 if (inet_pton(AF_INET6, optarg, &ifid) != 1)
154 help = true;
155 break;
156
157 case 'r':
158 optpos = optarg;
159 while (optpos[0]) {
160 opttype = htons(strtoul(optarg, &optpos, 10));
161 if (optpos == optarg)
162 break;
163 else if (optpos[0])
164 optarg = &optpos[1];
165 odhcp6c_add_state(STATE_ORO, &opttype, 2);
166 }
167 break;
168
169 case 'R':
170 client_options |= DHCPV6_STRICT_OPTIONS;
171 break;
172
173 case 'u':
174 optlen = htons(strlen(optarg));
175 odhcp6c_add_state(STATE_USERCLASS, &optlen, 2);
176 odhcp6c_add_state(STATE_USERCLASS, optarg, strlen(optarg));
177 break;
178
179 case 's':
180 script = optarg;
181 break;
182
183 case 'k':
184 release = false;
185 break;
186
187 case 't':
188 sol_timeout = atoi(optarg);
189 break;
190
191 case 'm':
192 min_update_interval = atoi(optarg);
193 break;
194
195 case 'e':
196 logopt |= LOG_PERROR;
197 break;
198
199 case 'd':
200 daemonize = true;
201 break;
202
203 case 'p':
204 pidfile = optarg;
205 break;
206
207 case 'f':
208 client_options &= ~DHCPV6_CLIENT_FQDN;
209 break;
210
211 case 'a':
212 client_options &= ~DHCPV6_ACCEPT_RECONFIGURE;
213 break;
214
215 case 'v':
216 ++verbosity;
217 break;
218
219 default:
220 help = true;
221 break;
222 }
223 }
224
225 openlog("odhcp6c", logopt, LOG_DAEMON);
226 if (!verbosity)
227 setlogmask(LOG_UPTO(LOG_WARNING));
228
229 const char *ifname = argv[optind];
230
231 if (help || !ifname)
232 return usage();
233
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);
241
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));
246 return 3;
247 }
248
249 if (daemonize) {
250 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
251 if (daemon(0, 0)) {
252 syslog(LOG_ERR, "Failed to daemonize: %s",
253 strerror(errno));
254 return 4;
255 }
256
257 char pidbuf[128];
258 if (!pidfile) {
259 snprintf(pidbuf, sizeof(pidbuf),
260 "/var/run/odhcp6c.%s.pid", ifname);
261 pidfile = pidbuf;
262 }
263
264 int fd = open(pidfile, O_WRONLY | O_CREAT, 0644);
265 if (fd >= 0) {
266 char buf[8];
267 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
268 write(fd, buf, len);
269 close(fd);
270 }
271 }
272
273 script_call("started");
274
275 while (!signal_term) { // Main logic
276 odhcp6c_clear_state(STATE_SERVER_ID);
277 odhcp6c_clear_state(STATE_SERVER_ADDR);
278 odhcp6c_clear_state(STATE_IA_NA);
279 odhcp6c_clear_state(STATE_IA_PD);
280 odhcp6c_clear_state(STATE_SNTP_IP);
281 odhcp6c_clear_state(STATE_NTP_IP);
282 odhcp6c_clear_state(STATE_NTP_FQDN);
283 odhcp6c_clear_state(STATE_SIP_IP);
284 odhcp6c_clear_state(STATE_SIP_FQDN);
285 dhcpv6_set_ia_mode(ia_na_mode, ia_pd_mode);
286 bound = false;
287
288 syslog(LOG_NOTICE, "(re)starting transaction on %s", ifname);
289
290 signal_usr1 = signal_usr2 = false;
291 int mode = dhcpv6_request(DHCPV6_MSG_SOLICIT);
292 odhcp6c_signal_process();
293
294 if (mode < 0)
295 continue;
296
297 do {
298 int res = dhcpv6_request(mode == DHCPV6_STATELESS ?
299 DHCPV6_MSG_INFO_REQ : DHCPV6_MSG_REQUEST);
300 bool signalled = odhcp6c_signal_process();
301
302 if (res > 0)
303 break;
304 else if (signalled) {
305 mode = -1;
306 break;
307 }
308
309 mode = dhcpv6_promote_server_cand();
310 } while (mode > DHCPV6_UNKNOWN);
311
312 if (mode < 0)
313 continue;
314
315 switch (mode) {
316 case DHCPV6_STATELESS:
317 bound = true;
318 syslog(LOG_NOTICE, "entering stateless-mode on %s", ifname);
319
320 while (!signal_usr2 && !signal_term) {
321 signal_usr1 = false;
322 script_call("informed");
323
324 int res = dhcpv6_poll_reconfigure();
325 odhcp6c_signal_process();
326
327 if (res > 0)
328 continue;
329
330 if (signal_usr1) {
331 signal_usr1 = false; // Acknowledged
332 continue;
333 }
334 if (signal_usr2 || signal_term)
335 break;
336
337 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
338 odhcp6c_signal_process();
339 if (signal_usr1)
340 continue;
341 else if (res < 0)
342 break;
343 }
344 break;
345
346 case DHCPV6_STATEFUL:
347 bound = true;
348 script_call("bound");
349 syslog(LOG_NOTICE, "entering stateful-mode on %s", ifname);
350
351 while (!signal_usr2 && !signal_term) {
352 // Renew Cycle
353 // Wait for T1 to expire or until we get a reconfigure
354 int res = dhcpv6_poll_reconfigure();
355 odhcp6c_signal_process();
356 if (res > 0) {
357 script_call("updated");
358 continue;
359 }
360
361 // Handle signal, if necessary
362 if (signal_usr1)
363 signal_usr1 = false; // Acknowledged
364 if (signal_usr2 || signal_term)
365 break; // Other signal type
366
367 // Send renew as T1 expired
368 res = dhcpv6_request(DHCPV6_MSG_RENEW);
369 odhcp6c_signal_process();
370 if (res > 0) { // Renew was succesfull
371 // Publish updates
372 script_call("updated");
373 continue; // Renew was successful
374 }
375
376 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
377 odhcp6c_clear_state(STATE_SERVER_ADDR);
378
379 size_t ia_pd_len, ia_na_len;
380 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
381 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
382
383 if (ia_pd_len == 0 && ia_na_len == 0)
384 break;
385
386 // If we have IAs, try rebind otherwise restart
387 res = dhcpv6_request(DHCPV6_MSG_REBIND);
388 odhcp6c_signal_process();
389
390 if (res > 0)
391 script_call("rebound");
392 else {
393 break;
394 }
395 }
396 break;
397
398 default:
399 break;
400 }
401
402 size_t ia_pd_len, ia_na_len, server_id_len;
403 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
404 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
405 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
406
407 // Add all prefixes to lost prefixes
408 bound = false;
409 script_call("unbound");
410
411 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0) && release)
412 dhcpv6_request(DHCPV6_MSG_RELEASE);
413
414 odhcp6c_clear_state(STATE_IA_NA);
415 odhcp6c_clear_state(STATE_IA_PD);
416 }
417
418 script_call("stopped");
419 return 0;
420 }
421
422
423 static int usage(void)
424 {
425 const char buf[] =
426 "Usage: odhcp6c [options] <interface>\n"
427 "\nFeature options:\n"
428 " -S <time> Wait at least <time> sec for a DHCP-server (0)\n"
429 " -N <mode> Mode for requesting addresses [try|force|none]\n"
430 " -P <length> Request IPv6-Prefix (0 = auto)\n"
431 " -F Force IPv6-Prefix\n"
432 " -V <class> Set vendor-class option (base-16 encoded)\n"
433 " -u <user-class> Set user-class option string\n"
434 " -c <clientid> Override client-ID (base-16 encoded)\n"
435 " -i <iface-id> Use a custom interface identifier for RA handling\n"
436 " -r <options> Options to be requested (comma-separated)\n"
437 " -R Do not request any options except those specified with -r\n"
438 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
439 " -a Don't send Accept Reconfigure option\n"
440 " -f Don't send Client FQDN option\n"
441 " -k Don't send a RELEASE when stopping\n"
442 " -t <seconds> Maximum timeout for DHCPv6-SOLICIT (3600)\n"
443 " -m <seconds> Minimum time between accepting updates (30)\n"
444 "\nInvocation options:\n"
445 " -p <pidfile> Set pidfile (/var/run/odhcp6c.pid)\n"
446 " -d Daemonize\n"
447 " -e Write logmessages to stderr\n"
448 " -v Increase logging verbosity\n"
449 " -h Show this help\n\n";
450 write(STDERR_FILENO, buf, sizeof(buf));
451 return 1;
452 }
453
454
455 // Don't want to pull-in librt and libpthread just for a monotonic clock...
456 uint64_t odhcp6c_get_milli_time(void)
457 {
458 struct timespec t = {0, 0};
459 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
460 return ((uint64_t)t.tv_sec) * 1000 + ((uint64_t)t.tv_nsec) / 1000000;
461 }
462
463
464 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
465 {
466 if (len == 0)
467 return state_data[state] + state_len[state];
468 else if (state_len[state] + len > 1024)
469 return NULL;
470
471 uint8_t *n = realloc(state_data[state], state_len[state] + len);
472 if (n || state_len[state] + len == 0) {
473 state_data[state] = n;
474 n += state_len[state];
475 state_len[state] += len;
476 }
477 return n;
478 }
479
480
481 bool odhcp6c_signal_process(void)
482 {
483 while (signal_io) {
484 signal_io = false;
485
486 bool ra_updated = ra_process();
487
488 if (ra_link_up())
489 signal_usr2 = true;
490
491 if (ra_updated && (bound || allow_slaac_only >= 0))
492 script_call("ra-updated"); // Immediate process urgent events
493 }
494
495 return signal_usr1 || signal_usr2 || signal_term;
496 }
497
498
499 void odhcp6c_clear_state(enum odhcp6c_state state)
500 {
501 state_len[state] = 0;
502 }
503
504
505 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
506 {
507 uint8_t *n = odhcp6c_resize_state(state, len);
508 if (n)
509 memcpy(n, data, len);
510 }
511
512 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len)
513 {
514 ssize_t len_after = state_len[state] - offset;
515 if (len_after < 0)
516 return;
517
518 uint8_t *n = odhcp6c_resize_state(state, len);
519 if (n) {
520 uint8_t *sdata = state_data[state];
521
522 memmove(sdata + offset + len, sdata + offset, len_after);
523 memcpy(sdata + offset, data, len);
524 }
525 }
526
527 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
528 {
529 uint8_t *data = state_data[state];
530 ssize_t len_after = state_len[state] - (offset + len);
531 if (len_after < 0)
532 return state_len[state];
533
534 memmove(data + offset, data + offset + len, len_after);
535 return state_len[state] -= len;
536 }
537
538
539 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len)
540 {
541 *len = state_len[state];
542 void *data = state_data[state];
543
544 state_len[state] = 0;
545 state_data[state] = NULL;
546
547 return data;
548 }
549
550
551 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
552 {
553 *len = state_len[state];
554 return state_data[state];
555 }
556
557
558 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
559 {
560 size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
561 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
562 struct odhcp6c_entry *x = NULL;
563
564 for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
565 if (!memcmp(c, new, cmplen))
566 return c;
567
568 return NULL;
569 }
570
571
572 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe)
573 {
574 size_t len;
575 struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
576 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
577
578 if (x && x->valid > new->valid && new->valid < safe)
579 new->valid = safe;
580
581 if (new->valid > 0) {
582 if (x) {
583 if (new->valid >= x->valid && new->valid != UINT32_MAX &&
584 new->valid - x->valid < min_update_interval &&
585 new->preferred >= x->preferred &&
586 new->preferred != UINT32_MAX &&
587 new->preferred - x->preferred < min_update_interval &&
588 x->class == new->class)
589 return false;
590 x->valid = new->valid;
591 x->preferred = new->preferred;
592 x->t1 = new->t1;
593 x->t2 = new->t2;
594 x->class = new->class;
595 x->iaid = new->iaid;
596 } else {
597 odhcp6c_add_state(state, new, sizeof(*new));
598 }
599 } else if (x) {
600 odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
601 }
602 return true;
603 }
604
605
606 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new)
607 {
608 return odhcp6c_update_entry_safe(state, new, 0);
609 }
610
611
612 static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
613 {
614 size_t len;
615 struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
616 for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
617 if (c->t1 < elapsed)
618 c->t1 = 0;
619 else if (c->t1 != UINT32_MAX)
620 c->t1 -= elapsed;
621
622 if (c->t2 < elapsed)
623 c->t2 = 0;
624 else if (c->t2 != UINT32_MAX)
625 c->t2 -= elapsed;
626
627 if (c->preferred < elapsed)
628 c->preferred = 0;
629 else if (c->preferred != UINT32_MAX)
630 c->preferred -= elapsed;
631
632 if (c->valid < elapsed)
633 c->valid = 0;
634 else if (c->valid != UINT32_MAX)
635 c->valid -= elapsed;
636
637 if (!c->valid)
638 odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
639 }
640 }
641
642
643 void odhcp6c_expire(void)
644 {
645 time_t now = odhcp6c_get_milli_time() / 1000;
646 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
647 last_update = now;
648
649 odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
650 odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
651 odhcp6c_expire_list(STATE_RA_DNS, elapsed);
652 odhcp6c_expire_list(STATE_IA_NA, elapsed);
653 odhcp6c_expire_list(STATE_IA_PD, elapsed);
654 }
655
656
657 uint32_t odhcp6c_elapsed(void)
658 {
659 return odhcp6c_get_milli_time() / 1000 - last_update;
660 }
661
662
663 void odhcp6c_random(void *buf, size_t len)
664 {
665 read(urandom_fd, buf, len);
666 }
667
668 bool odhcp6c_is_bound(void)
669 {
670 return bound;
671 }
672
673 static void sighandler(int signal)
674 {
675 if (signal == SIGCHLD)
676 while (waitpid(-1, NULL, WNOHANG) > 0);
677 else if (signal == SIGUSR1)
678 signal_usr1 = true;
679 else if (signal == SIGUSR2)
680 signal_usr2 = true;
681 else if (signal == SIGIO)
682 signal_io = true;
683 else
684 signal_term = true;
685 }
Openwrt DHCPv6 Client