1 /* $FreeBSD: stable/10/usr.sbin/rtadvd/rtadvd.c 275038 2014-11-25 13:12:45Z dim $ */
2 /* $KAME: rtadvd.c,v 1.82 2003/08/05 12:34:23 itojun Exp $ */
3
4 /*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org>
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the project nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include <sys/param.h>
35 #include <sys/ioctl.h>
36 #include <sys/socket.h>
37 #include <sys/uio.h>
38 #include <sys/queue.h>
39 #include <sys/stat.h>
40 #include <sys/sysctl.h>
41
42 #include <net/if.h>
43 #include <net/if_types.h>
44 #include <net/if_media.h>
45 #include <net/if_dl.h>
46 #include <net/route.h>
47 #include <netinet/in.h>
48 #include <netinet/ip6.h>
49 #include <netinet6/ip6_var.h>
50 #include <netinet/icmp6.h>
51
52 #include <arpa/inet.h>
53
54 #include <net/if_var.h>
55 #include <netinet/in_var.h>
56 #include <netinet6/nd6.h>
57
58 #include <time.h>
59 #include <unistd.h>
60 #include <stdio.h>
61 #include <err.h>
62 #include <errno.h>
63 #include <inttypes.h>
64 #include <libutil.h>
65 #include <netdb.h>
66 #include <signal.h>
67 #include <string.h>
68 #include <stdlib.h>
69 #include <syslog.h>
70 #include <poll.h>
71
72 #include "pathnames.h"
73 #include "rtadvd.h"
74 #include "if.h"
75 #include "rrenum.h"
76 #include "advcap.h"
77 #include "timer_subr.h"
78 #include "timer.h"
79 #include "config.h"
80 #include "control.h"
81 #include "control_server.h"
82
83 #define RTADV_TYPE2BITMASK(type) (0x1 << type)
84
85 struct msghdr rcvmhdr;
86 static char *rcvcmsgbuf;
87 static size_t rcvcmsgbuflen;
88 static char *sndcmsgbuf = NULL;
89 static size_t sndcmsgbuflen;
90 struct msghdr sndmhdr;
91 struct iovec rcviov[2];
92 struct iovec sndiov[2];
93 struct sockaddr_in6 rcvfrom;
94 static const char *pidfilename = _PATH_RTADVDPID;
95 const char *conffile = _PATH_RTADVDCONF;
96 static struct pidfh *pfh;
97 static int dflag, sflag;
98 static int wait_shutdown;
99
100 #define PFD_RAWSOCK 0
101 #define PFD_RTSOCK 1
102 #define PFD_CSOCK 2
103 #define PFD_MAX 3
104
105 struct railist_head_t railist =
106 TAILQ_HEAD_INITIALIZER(railist);
107 struct ifilist_head_t ifilist =
108 TAILQ_HEAD_INITIALIZER(ifilist);
109
110 struct nd_optlist {
111 TAILQ_ENTRY(nd_optlist) nol_next;
112 struct nd_opt_hdr *nol_opt;
113 };
114 union nd_opt {
115 struct nd_opt_hdr *opt_array[9];
116 struct {
117 struct nd_opt_hdr *zero;
118 struct nd_opt_hdr *src_lladdr;
119 struct nd_opt_hdr *tgt_lladdr;
120 struct nd_opt_prefix_info *pi;
121 struct nd_opt_rd_hdr *rh;
122 struct nd_opt_mtu *mtu;
123 TAILQ_HEAD(, nd_optlist) opt_list;
124 } nd_opt_each;
125 };
126 #define opt_src_lladdr nd_opt_each.src_lladdr
127 #define opt_tgt_lladdr nd_opt_each.tgt_lladdr
128 #define opt_pi nd_opt_each.pi
129 #define opt_rh nd_opt_each.rh
130 #define opt_mtu nd_opt_each.mtu
131 #define opt_list nd_opt_each.opt_list
132
133 #define NDOPT_FLAG_SRCLINKADDR (1 << 0)
134 #define NDOPT_FLAG_TGTLINKADDR (1 << 1)
135 #define NDOPT_FLAG_PREFIXINFO (1 << 2)
136 #define NDOPT_FLAG_RDHDR (1 << 3)
137 #define NDOPT_FLAG_MTU (1 << 4)
138 #define NDOPT_FLAG_RDNSS (1 << 5)
139 #define NDOPT_FLAG_DNSSL (1 << 6)
140
141 static uint32_t ndopt_flags[] = {
142 [ND_OPT_SOURCE_LINKADDR] = NDOPT_FLAG_SRCLINKADDR,
143 [ND_OPT_TARGET_LINKADDR] = NDOPT_FLAG_TGTLINKADDR,
144 [ND_OPT_PREFIX_INFORMATION] = NDOPT_FLAG_PREFIXINFO,
145 [ND_OPT_REDIRECTED_HEADER] = NDOPT_FLAG_RDHDR,
146 [ND_OPT_MTU] = NDOPT_FLAG_MTU,
147 [ND_OPT_RDNSS] = NDOPT_FLAG_RDNSS,
148 [ND_OPT_DNSSL] = NDOPT_FLAG_DNSSL,
149 };
150
151 static void rtadvd_shutdown(void);
152 static void sock_open(struct sockinfo *);
153 static void rtsock_open(struct sockinfo *);
154 static void rtadvd_input(struct sockinfo *);
155 static void rs_input(int, struct nd_router_solicit *,
156 struct in6_pktinfo *, struct sockaddr_in6 *);
157 static void ra_input(int, struct nd_router_advert *,
158 struct in6_pktinfo *, struct sockaddr_in6 *);
159 static int prefix_check(struct nd_opt_prefix_info *, struct rainfo *,
160 struct sockaddr_in6 *);
161 static int nd6_options(struct nd_opt_hdr *, int,
162 union nd_opt *, uint32_t);
163 static void free_ndopts(union nd_opt *);
164 static void rtmsg_input(struct sockinfo *);
165 static void set_short_delay(struct ifinfo *);
166 static int check_accept_rtadv(int);
167
168 static void
usage(void)169 usage(void)
170 {
171
172 fprintf(stderr, "usage: rtadvd [-dDfRs] "
173 "[-c configfile] [-C ctlsock] [-M ifname] [-p pidfile]\n");
174 exit(1);
175 }
176
177 int
main(int argc,char * argv[])178 main(int argc, char *argv[])
179 {
180 struct pollfd set[PFD_MAX];
181 struct timespec *timeout;
182 int i, ch;
183 int fflag = 0, logopt;
184 int error;
185 pid_t otherpid;
186
187 /* get command line options and arguments */
188 while ((ch = getopt(argc, argv, "c:C:dDfhM:p:Rs")) != -1) {
189 switch (ch) {
190 case 'c':
191 conffile = optarg;
192 break;
193 case 'C':
194 ctrlsock.si_name = optarg;
195 break;
196 case 'd':
197 dflag++;
198 break;
199 case 'D':
200 dflag += 3;
201 break;
202 case 'f':
203 fflag = 1;
204 break;
205 case 'M':
206 mcastif = optarg;
207 break;
208 case 'R':
209 fprintf(stderr, "rtadvd: "
210 "the -R option is currently ignored.\n");
211 /* accept_rr = 1; */
212 /* run anyway... */
213 break;
214 case 's':
215 sflag = 1;
216 break;
217 case 'p':
218 pidfilename = optarg;
219 break;
220 default:
221 usage();
222 }
223 }
224 argc -= optind;
225 argv += optind;
226
227 logopt = LOG_NDELAY | LOG_PID;
228 if (fflag)
229 logopt |= LOG_PERROR;
230 openlog("rtadvd", logopt, LOG_DAEMON);
231
232 /* set log level */
233 if (dflag > 2)
234 (void)setlogmask(LOG_UPTO(LOG_DEBUG));
235 else if (dflag > 1)
236 (void)setlogmask(LOG_UPTO(LOG_INFO));
237 else if (dflag > 0)
238 (void)setlogmask(LOG_UPTO(LOG_NOTICE));
239 else
240 (void)setlogmask(LOG_UPTO(LOG_ERR));
241
242 /* timer initialization */
243 rtadvd_timer_init();
244
245 #ifndef HAVE_ARC4RANDOM
246 /* random value initialization */
247 srandomdev();
248 #endif
249 pfh = pidfile_open(pidfilename, 0600, &otherpid);
250 if (pfh == NULL) {
251 if (errno == EEXIST)
252 errx(1, "%s already running, pid: %d",
253 getprogname(), otherpid);
254 syslog(LOG_ERR,
255 "failed to open the pid file %s, run anyway.",
256 pidfilename);
257 }
258 if (!fflag)
259 daemon(1, 0);
260
261 sock_open(&sock);
262
263 update_ifinfo(&ifilist, UPDATE_IFINFO_ALL);
264 for (i = 0; i < argc; i++)
265 update_persist_ifinfo(&ifilist, argv[i]);
266
267 csock_open(&ctrlsock, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
268 if (ctrlsock.si_fd == -1) {
269 syslog(LOG_ERR, "cannot open control socket: %s",
270 strerror(errno));
271 exit(1);
272 }
273
274 /* record the current PID */
275 pidfile_write(pfh);
276
277 set[PFD_RAWSOCK].fd = sock.si_fd;
278 set[PFD_RAWSOCK].events = POLLIN;
279 if (sflag == 0) {
280 rtsock_open(&rtsock);
281 set[PFD_RTSOCK].fd = rtsock.si_fd;
282 set[PFD_RTSOCK].events = POLLIN;
283 } else
284 set[PFD_RTSOCK].fd = -1;
285 set[PFD_CSOCK].fd = ctrlsock.si_fd;
286 set[PFD_CSOCK].events = POLLIN;
287 signal(SIGTERM, set_do_shutdown);
288 signal(SIGINT, set_do_shutdown);
289 signal(SIGHUP, set_do_reload);
290
291 error = csock_listen(&ctrlsock);
292 if (error) {
293 syslog(LOG_ERR, "cannot listen control socket: %s",
294 strerror(errno));
295 exit(1);
296 }
297
298 /* load configuration file */
299 set_do_reload(0);
300
301 while (1) {
302 if (is_do_shutdown())
303 rtadvd_shutdown();
304
305 if (is_do_reload()) {
306 loadconfig_ifname(reload_ifname());
307 if (reload_ifname() == NULL)
308 syslog(LOG_INFO,
309 "configuration file reloaded.");
310 else
311 syslog(LOG_INFO,
312 "configuration file for %s reloaded.",
313 reload_ifname());
314 reset_do_reload();
315 }
316
317 /* timeout handler update for active interfaces */
318 rtadvd_update_timeout_handler();
319
320 /* timer expiration check and reset the timer */
321 timeout = rtadvd_check_timer();
322
323 if (timeout != NULL) {
324 syslog(LOG_DEBUG,
325 "<%s> set timer to %ld:%ld. waiting for "
326 "inputs or timeout", __func__,
327 (long int)timeout->tv_sec,
328 (long int)timeout->tv_nsec / 1000);
329 } else {
330 syslog(LOG_DEBUG,
331 "<%s> there's no timer. waiting for inputs",
332 __func__);
333 }
334 if ((i = poll(set, NELEM(set),
335 timeout ? (timeout->tv_sec * 1000 +
336 timeout->tv_nsec / 1000 / 1000) : INFTIM)) < 0) {
337
338 /* EINTR would occur if a signal was delivered */
339 if (errno != EINTR)
340 syslog(LOG_ERR, "poll() failed: %s",
341 strerror(errno));
342 continue;
343 }
344 if (i == 0) /* timeout */
345 continue;
346 if (rtsock.si_fd != -1 && set[PFD_RTSOCK].revents & POLLIN)
347 rtmsg_input(&rtsock);
348
349 if (set[PFD_RAWSOCK].revents & POLLIN)
350 rtadvd_input(&sock);
351
352 if (set[PFD_CSOCK].revents & POLLIN) {
353 int fd;
354
355 fd = csock_accept(&ctrlsock);
356 if (fd == -1)
357 syslog(LOG_ERR,
358 "cannot accept() control socket: %s",
359 strerror(errno));
360 else {
361 cm_handler_server(fd);
362 close(fd);
363 }
364 }
365 }
366 exit(0); /* NOTREACHED */
367 }
368
369 static void
rtadvd_shutdown(void)370 rtadvd_shutdown(void)
371 {
372 struct ifinfo *ifi;
373 struct rainfo *rai;
374 struct rdnss *rdn;
375 struct dnssl *dns;
376
377 if (wait_shutdown) {
378 syslog(LOG_INFO,
379 "waiting expiration of the all RA timers.");
380
381 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
382 /*
383 * Ignore !IFF_UP interfaces in waiting for shutdown.
384 */
385 if (!(ifi->ifi_flags & IFF_UP) &&
386 ifi->ifi_ra_timer != NULL) {
387 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
388 rtadvd_remove_timer(ifi->ifi_ra_timer);
389 ifi->ifi_ra_timer = NULL;
390 syslog(LOG_DEBUG, "<%s> %s(idx=%d) is down. "
391 "Timer removed and marked as UNCONFIGURED.",
392 __func__, ifi->ifi_ifname,
393 ifi->ifi_ifindex);
394 }
395 }
396 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
397 if (ifi->ifi_ra_timer != NULL)
398 break;
399 }
400 if (ifi == NULL) {
401 syslog(LOG_NOTICE, "gracefully terminated.");
402 exit(0);
403 }
404
405 sleep(1);
406 return;
407 }
408
409 syslog(LOG_DEBUG, "<%s> cease to be an advertising router",
410 __func__);
411
412 wait_shutdown = 1;
413
414 TAILQ_FOREACH(rai, &railist, rai_next) {
415 rai->rai_lifetime = 0;
416 TAILQ_FOREACH(rdn, &rai->rai_rdnss, rd_next)
417 rdn->rd_ltime = 0;
418 TAILQ_FOREACH(dns, &rai->rai_dnssl, dn_next)
419 dns->dn_ltime = 0;
420 }
421 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
422 if (!ifi->ifi_persist)
423 continue;
424 if (ifi->ifi_state == IFI_STATE_UNCONFIGURED)
425 continue;
426 if (ifi->ifi_ra_timer == NULL)
427 continue;
428 if (ifi->ifi_ra_lastsent.tv_sec == 0 &&
429 ifi->ifi_ra_lastsent.tv_nsec == 0 &&
430 ifi->ifi_ra_timer != NULL) {
431 /*
432 * When RA configured but never sent,
433 * ignore the IF immediately.
434 */
435 rtadvd_remove_timer(ifi->ifi_ra_timer);
436 ifi->ifi_ra_timer = NULL;
437 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
438 continue;
439 }
440
441 ifi->ifi_state = IFI_STATE_TRANSITIVE;
442
443 /* Mark as the shut-down state. */
444 ifi->ifi_rainfo_trans = ifi->ifi_rainfo;
445 ifi->ifi_rainfo = NULL;
446
447 ifi->ifi_burstcount = MAX_FINAL_RTR_ADVERTISEMENTS;
448 ifi->ifi_burstinterval = MIN_DELAY_BETWEEN_RAS;
449
450 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
451 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
452 ifi->ifi_ra_timer);
453 }
454 syslog(LOG_NOTICE, "final RA transmission started.");
455
456 pidfile_remove(pfh);
457 csock_close(&ctrlsock);
458 }
459
460 static void
rtmsg_input(struct sockinfo * s)461 rtmsg_input(struct sockinfo *s)
462 {
463 int n, type, ifindex = 0, plen;
464 size_t len;
465 char msg[2048], *next, *lim;
466 char ifname[IFNAMSIZ];
467 struct if_announcemsghdr *ifan;
468 struct rt_msghdr *rtm;
469 struct prefix *pfx;
470 struct rainfo *rai;
471 struct in6_addr *addr;
472 struct ifinfo *ifi;
473 char addrbuf[INET6_ADDRSTRLEN];
474 int prefixchange = 0;
475
476 if (s == NULL) {
477 syslog(LOG_ERR, "<%s> internal error", __func__);
478 exit(1);
479 }
480 n = read(s->si_fd, msg, sizeof(msg));
481 rtm = (struct rt_msghdr *)msg;
482 syslog(LOG_DEBUG, "<%s> received a routing message "
483 "(type = %d, len = %d)", __func__, rtm->rtm_type, n);
484
485 if (n > rtm->rtm_msglen) {
486 /*
487 * This usually won't happen for messages received on
488 * a routing socket.
489 */
490 syslog(LOG_DEBUG,
491 "<%s> received data length is larger than "
492 "1st routing message len. multiple messages? "
493 "read %d bytes, but 1st msg len = %d",
494 __func__, n, rtm->rtm_msglen);
495 #if 0
496 /* adjust length */
497 n = rtm->rtm_msglen;
498 #endif
499 }
500
501 lim = msg + n;
502 for (next = msg; next < lim; next += len) {
503 int oldifflags;
504
505 next = get_next_msg(next, lim, 0, &len,
506 RTADV_TYPE2BITMASK(RTM_ADD) |
507 RTADV_TYPE2BITMASK(RTM_DELETE) |
508 RTADV_TYPE2BITMASK(RTM_NEWADDR) |
509 RTADV_TYPE2BITMASK(RTM_DELADDR) |
510 RTADV_TYPE2BITMASK(RTM_IFINFO) |
511 RTADV_TYPE2BITMASK(RTM_IFANNOUNCE));
512 if (len == 0)
513 break;
514 type = ((struct rt_msghdr *)next)->rtm_type;
515 switch (type) {
516 case RTM_ADD:
517 case RTM_DELETE:
518 ifindex = get_rtm_ifindex(next);
519 break;
520 case RTM_NEWADDR:
521 case RTM_DELADDR:
522 ifindex = (int)((struct ifa_msghdr *)next)->ifam_index;
523 break;
524 case RTM_IFINFO:
525 ifindex = (int)((struct if_msghdr *)next)->ifm_index;
526 break;
527 case RTM_IFANNOUNCE:
528 ifan = (struct if_announcemsghdr *)next;
529 switch (ifan->ifan_what) {
530 case IFAN_ARRIVAL:
531 case IFAN_DEPARTURE:
532 break;
533 default:
534 syslog(LOG_DEBUG,
535 "<%s:%d> unknown ifan msg (ifan_what=%d)",
536 __func__, __LINE__, ifan->ifan_what);
537 continue;
538 }
539
540 syslog(LOG_DEBUG, "<%s>: if_announcemsg (idx=%d:%d)",
541 __func__, ifan->ifan_index, ifan->ifan_what);
542 switch (ifan->ifan_what) {
543 case IFAN_ARRIVAL:
544 syslog(LOG_NOTICE,
545 "interface added (idx=%d)",
546 ifan->ifan_index);
547 update_ifinfo(&ifilist, ifan->ifan_index);
548 loadconfig_index(ifan->ifan_index);
549 break;
550 case IFAN_DEPARTURE:
551 syslog(LOG_NOTICE,
552 "interface removed (idx=%d)",
553 ifan->ifan_index);
554 rm_ifinfo_index(ifan->ifan_index);
555
556 /* Clear ifi_ifindex */
557 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
558 if (ifi->ifi_ifindex
559 == ifan->ifan_index) {
560 ifi->ifi_ifindex = 0;
561 break;
562 }
563 }
564 update_ifinfo(&ifilist, ifan->ifan_index);
565 break;
566 }
567 continue;
568 default:
569 /* should not reach here */
570 syslog(LOG_DEBUG,
571 "<%s:%d> unknown rtmsg %d on %s",
572 __func__, __LINE__, type,
573 if_indextoname(ifindex, ifname));
574 continue;
575 }
576 ifi = if_indextoifinfo(ifindex);
577 if (ifi == NULL) {
578 syslog(LOG_DEBUG,
579 "<%s> ifinfo not found for idx=%d. Why?",
580 __func__, ifindex);
581 continue;
582 }
583 rai = ifi->ifi_rainfo;
584 if (rai == NULL) {
585 syslog(LOG_DEBUG,
586 "<%s> route changed on "
587 "non advertising interface(%s)",
588 __func__, ifi->ifi_ifname);
589 continue;
590 }
591
592 oldifflags = ifi->ifi_flags;
593 /* init ifflags because it may have changed */
594 update_ifinfo(&ifilist, ifindex);
595
596 switch (type) {
597 case RTM_ADD:
598 if (sflag)
599 break; /* we aren't interested in prefixes */
600
601 addr = get_addr(msg);
602 plen = get_prefixlen(msg);
603 /* sanity check for plen */
604 /* as RFC2373, prefixlen is at least 4 */
605 if (plen < 4 || plen > 127) {
606 syslog(LOG_INFO, "<%s> new interface route's"
607 "plen %d is invalid for a prefix",
608 __func__, plen);
609 break;
610 }
611 pfx = find_prefix(rai, addr, plen);
612 if (pfx) {
613 if (pfx->pfx_timer) {
614 /*
615 * If the prefix has been invalidated,
616 * make it available again.
617 */
618 update_prefix(pfx);
619 prefixchange = 1;
620 } else
621 syslog(LOG_DEBUG,
622 "<%s> new prefix(%s/%d) "
623 "added on %s, "
624 "but it was already in list",
625 __func__,
626 inet_ntop(AF_INET6, addr,
627 (char *)addrbuf,
628 sizeof(addrbuf)),
629 plen, ifi->ifi_ifname);
630 break;
631 }
632 make_prefix(rai, ifindex, addr, plen);
633 prefixchange = 1;
634 break;
635 case RTM_DELETE:
636 if (sflag)
637 break;
638
639 addr = get_addr(msg);
640 plen = get_prefixlen(msg);
641 /* sanity check for plen */
642 /* as RFC2373, prefixlen is at least 4 */
643 if (plen < 4 || plen > 127) {
644 syslog(LOG_INFO,
645 "<%s> deleted interface route's "
646 "plen %d is invalid for a prefix",
647 __func__, plen);
648 break;
649 }
650 pfx = find_prefix(rai, addr, plen);
651 if (pfx == NULL) {
652 syslog(LOG_DEBUG,
653 "<%s> prefix(%s/%d) was deleted on %s, "
654 "but it was not in list",
655 __func__, inet_ntop(AF_INET6, addr,
656 (char *)addrbuf, sizeof(addrbuf)),
657 plen, ifi->ifi_ifname);
658 break;
659 }
660 invalidate_prefix(pfx);
661 prefixchange = 1;
662 break;
663 case RTM_NEWADDR:
664 case RTM_DELADDR:
665 case RTM_IFINFO:
666 break;
667 default:
668 /* should not reach here */
669 syslog(LOG_DEBUG,
670 "<%s:%d> unknown rtmsg %d on %s",
671 __func__, __LINE__, type,
672 if_indextoname(ifindex, ifname));
673 return;
674 }
675
676 /* check if an interface flag is changed */
677 if ((oldifflags & IFF_UP) && /* UP to DOWN */
678 !(ifi->ifi_flags & IFF_UP)) {
679 syslog(LOG_NOTICE,
680 "<interface %s becomes down. stop timer.",
681 ifi->ifi_ifname);
682 rtadvd_remove_timer(ifi->ifi_ra_timer);
683 ifi->ifi_ra_timer = NULL;
684 } else if (!(oldifflags & IFF_UP) && /* DOWN to UP */
685 (ifi->ifi_flags & IFF_UP)) {
686 syslog(LOG_NOTICE,
687 "interface %s becomes up. restart timer.",
688 ifi->ifi_ifname);
689
690 ifi->ifi_state = IFI_STATE_TRANSITIVE;
691 ifi->ifi_burstcount =
692 MAX_INITIAL_RTR_ADVERTISEMENTS;
693 ifi->ifi_burstinterval =
694 MAX_INITIAL_RTR_ADVERT_INTERVAL;
695
696 ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout,
697 ra_timer_update, ifi, ifi);
698 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
699 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
700 ifi->ifi_ra_timer);
701 } else if (prefixchange &&
702 (ifi->ifi_flags & IFF_UP)) {
703 /*
704 * An advertised prefix has been added or invalidated.
705 * Will notice the change in a short delay.
706 */
707 set_short_delay(ifi);
708 }
709 }
710
711 return;
712 }
713
714 void
rtadvd_input(struct sockinfo * s)715 rtadvd_input(struct sockinfo *s)
716 {
717 ssize_t i;
718 int *hlimp = NULL;
719 #ifdef OLDRAWSOCKET
720 struct ip6_hdr *ip;
721 #endif
722 struct icmp6_hdr *icp;
723 int ifindex = 0;
724 struct cmsghdr *cm;
725 struct in6_pktinfo *pi = NULL;
726 char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
727 struct in6_addr dst = in6addr_any;
728 struct ifinfo *ifi;
729
730 syslog(LOG_DEBUG, "<%s> enter", __func__);
731
732 if (s == NULL) {
733 syslog(LOG_ERR, "<%s> internal error", __func__);
734 exit(1);
735 }
736 /*
737 * Get message. We reset msg_controllen since the field could
738 * be modified if we had received a message before setting
739 * receive options.
740 */
741 rcvmhdr.msg_controllen = rcvcmsgbuflen;
742 if ((i = recvmsg(s->si_fd, &rcvmhdr, 0)) < 0)
743 return;
744
745 /* extract optional information via Advanced API */
746 for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr);
747 cm;
748 cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) {
749 if (cm->cmsg_level == IPPROTO_IPV6 &&
750 cm->cmsg_type == IPV6_PKTINFO &&
751 cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) {
752 pi = (struct in6_pktinfo *)(CMSG_DATA(cm));
753 ifindex = pi->ipi6_ifindex;
754 dst = pi->ipi6_addr;
755 }
756 if (cm->cmsg_level == IPPROTO_IPV6 &&
757 cm->cmsg_type == IPV6_HOPLIMIT &&
758 cm->cmsg_len == CMSG_LEN(sizeof(int)))
759 hlimp = (int *)CMSG_DATA(cm);
760 }
761 if (ifindex == 0) {
762 syslog(LOG_ERR, "failed to get receiving interface");
763 return;
764 }
765 if (hlimp == NULL) {
766 syslog(LOG_ERR, "failed to get receiving hop limit");
767 return;
768 }
769
770 /*
771 * If we happen to receive data on an interface which is now gone
772 * or down, just discard the data.
773 */
774 ifi = if_indextoifinfo(pi->ipi6_ifindex);
775 if (ifi == NULL || !(ifi->ifi_flags & IFF_UP)) {
776 syslog(LOG_INFO,
777 "<%s> received data on a disabled interface (%s)",
778 __func__,
779 (ifi == NULL) ? "[gone]" : ifi->ifi_ifname);
780 return;
781 }
782
783 #ifdef OLDRAWSOCKET
784 if ((size_t)i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) {
785 syslog(LOG_ERR,
786 "packet size(%d) is too short", i);
787 return;
788 }
789
790 ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base;
791 icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */
792 #else
793 if ((size_t)i < sizeof(struct icmp6_hdr)) {
794 syslog(LOG_ERR, "packet size(%zd) is too short", i);
795 return;
796 }
797
798 icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base;
799 #endif
800
801 switch (icp->icmp6_type) {
802 case ND_ROUTER_SOLICIT:
803 /*
804 * Message verification - RFC 4861 6.1.1
805 * XXX: these checks must be done in the kernel as well,
806 * but we can't completely rely on them.
807 */
808 if (*hlimp != 255) {
809 syslog(LOG_NOTICE,
810 "RS with invalid hop limit(%d) "
811 "received from %s on %s",
812 *hlimp,
813 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
814 sizeof(ntopbuf)),
815 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
816 return;
817 }
818 if (icp->icmp6_code) {
819 syslog(LOG_NOTICE,
820 "RS with invalid ICMP6 code(%d) "
821 "received from %s on %s",
822 icp->icmp6_code,
823 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
824 sizeof(ntopbuf)),
825 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
826 return;
827 }
828 if ((size_t)i < sizeof(struct nd_router_solicit)) {
829 syslog(LOG_NOTICE,
830 "RS from %s on %s does not have enough "
831 "length (len = %zd)",
832 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
833 sizeof(ntopbuf)),
834 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
835 return;
836 }
837 rs_input(i, (struct nd_router_solicit *)icp, pi, &rcvfrom);
838 break;
839 case ND_ROUTER_ADVERT:
840 /*
841 * Message verification - RFC 4861 6.1.2
842 * XXX: there's the same dilemma as above...
843 */
844 if (!IN6_IS_ADDR_LINKLOCAL(&rcvfrom.sin6_addr)) {
845 syslog(LOG_NOTICE,
846 "RA with non-linklocal source address "
847 "received from %s on %s",
848 inet_ntop(AF_INET6, &rcvfrom.sin6_addr,
849 ntopbuf, sizeof(ntopbuf)),
850 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
851 return;
852 }
853 if (*hlimp != 255) {
854 syslog(LOG_NOTICE,
855 "RA with invalid hop limit(%d) "
856 "received from %s on %s",
857 *hlimp,
858 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
859 sizeof(ntopbuf)),
860 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
861 return;
862 }
863 if (icp->icmp6_code) {
864 syslog(LOG_NOTICE,
865 "RA with invalid ICMP6 code(%d) "
866 "received from %s on %s",
867 icp->icmp6_code,
868 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
869 sizeof(ntopbuf)),
870 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
871 return;
872 }
873 if ((size_t)i < sizeof(struct nd_router_advert)) {
874 syslog(LOG_NOTICE,
875 "RA from %s on %s does not have enough "
876 "length (len = %zd)",
877 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
878 sizeof(ntopbuf)),
879 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
880 return;
881 }
882 ra_input(i, (struct nd_router_advert *)icp, pi, &rcvfrom);
883 break;
884 case ICMP6_ROUTER_RENUMBERING:
885 if (mcastif == NULL) {
886 syslog(LOG_ERR, "received a router renumbering "
887 "message, but not allowed to be accepted");
888 break;
889 }
890 rr_input(i, (struct icmp6_router_renum *)icp, pi, &rcvfrom,
891 &dst);
892 break;
893 default:
894 /*
895 * Note that this case is POSSIBLE, especially just
896 * after invocation of the daemon. This is because we
897 * could receive message after opening the socket and
898 * before setting ICMP6 type filter(see sock_open()).
899 */
900 syslog(LOG_ERR, "invalid icmp type(%d)", icp->icmp6_type);
901 return;
902 }
903
904 return;
905 }
906
907 static void
rs_input(int len,struct nd_router_solicit * rs,struct in6_pktinfo * pi,struct sockaddr_in6 * from)908 rs_input(int len, struct nd_router_solicit *rs,
909 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
910 {
911 char ntopbuf[INET6_ADDRSTRLEN];
912 char ifnamebuf[IFNAMSIZ];
913 union nd_opt ndopts;
914 struct rainfo *rai;
915 struct ifinfo *ifi;
916 struct soliciter *sol;
917
918 syslog(LOG_DEBUG,
919 "<%s> RS received from %s on %s",
920 __func__,
921 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)),
922 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
923
924 /* ND option check */
925 memset(&ndopts, 0, sizeof(ndopts));
926 TAILQ_INIT(&ndopts.opt_list);
927 if (nd6_options((struct nd_opt_hdr *)(rs + 1),
928 len - sizeof(struct nd_router_solicit),
929 &ndopts, NDOPT_FLAG_SRCLINKADDR)) {
930 syslog(LOG_INFO,
931 "<%s> ND option check failed for an RS from %s on %s",
932 __func__,
933 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
934 sizeof(ntopbuf)),
935 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
936 return;
937 }
938
939 /*
940 * If the IP source address is the unspecified address, there
941 * must be no source link-layer address option in the message.
942 * (RFC 4861 6.1.1)
943 */
944 if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) &&
945 ndopts.opt_src_lladdr) {
946 syslog(LOG_INFO,
947 "<%s> RS from unspecified src on %s has a link-layer"
948 " address option",
949 __func__, if_indextoname(pi->ipi6_ifindex, ifnamebuf));
950 goto done;
951 }
952
953 ifi = if_indextoifinfo(pi->ipi6_ifindex);
954 if (ifi == NULL) {
955 syslog(LOG_INFO,
956 "<%s> if (idx=%d) not found. Why?",
957 __func__, pi->ipi6_ifindex);
958 goto done;
959 }
960 rai = ifi->ifi_rainfo;
961 if (rai == NULL) {
962 syslog(LOG_INFO,
963 "<%s> RS received on non advertising interface(%s)",
964 __func__,
965 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
966 goto done;
967 }
968
969 rai->rai_ifinfo->ifi_rsinput++;
970
971 /*
972 * Decide whether to send RA according to the rate-limit
973 * consideration.
974 */
975
976 /* record sockaddr waiting for RA, if possible */
977 sol = (struct soliciter *)malloc(sizeof(*sol));
978 if (sol) {
979 sol->sol_addr = *from;
980 /* XXX RFC 2553 need clarification on flowinfo */
981 sol->sol_addr.sin6_flowinfo = 0;
982 TAILQ_INSERT_TAIL(&rai->rai_soliciter, sol, sol_next);
983 }
984
985 /*
986 * If there is already a waiting RS packet, don't
987 * update the timer.
988 */
989 if (ifi->ifi_rs_waitcount++)
990 goto done;
991
992 set_short_delay(ifi);
993
994 done:
995 free_ndopts(&ndopts);
996 return;
997 }
998
999 static void
set_short_delay(struct ifinfo * ifi)1000 set_short_delay(struct ifinfo *ifi)
1001 {
1002 long delay; /* must not be greater than 1000000 */
1003 struct timespec interval, now, min_delay, tm_tmp, *rest;
1004
1005 if (ifi->ifi_ra_timer == NULL)
1006 return;
1007 /*
1008 * Compute a random delay. If the computed value
1009 * corresponds to a time later than the time the next
1010 * multicast RA is scheduled to be sent, ignore the random
1011 * delay and send the advertisement at the
1012 * already-scheduled time. RFC 4861 6.2.6
1013 */
1014 #ifdef HAVE_ARC4RANDOM
1015 delay = arc4random_uniform(MAX_RA_DELAY_TIME);
1016 #else
1017 delay = random() % MAX_RA_DELAY_TIME;
1018 #endif
1019 interval.tv_sec = 0;
1020 interval.tv_nsec = delay * 1000;
1021 rest = rtadvd_timer_rest(ifi->ifi_ra_timer);
1022 if (TS_CMP(rest, &interval, <)) {
1023 syslog(LOG_DEBUG, "<%s> random delay is larger than "
1024 "the rest of the current timer", __func__);
1025 interval = *rest;
1026 }
1027
1028 /*
1029 * If we sent a multicast Router Advertisement within
1030 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule
1031 * the advertisement to be sent at a time corresponding to
1032 * MIN_DELAY_BETWEEN_RAS plus the random value after the
1033 * previous advertisement was sent.
1034 */
1035 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1036 TS_SUB(&now, &ifi->ifi_ra_lastsent, &tm_tmp);
1037 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS;
1038 min_delay.tv_nsec = 0;
1039 if (TS_CMP(&tm_tmp, &min_delay, <)) {
1040 TS_SUB(&min_delay, &tm_tmp, &min_delay);
1041 TS_ADD(&min_delay, &interval, &interval);
1042 }
1043 rtadvd_set_timer(&interval, ifi->ifi_ra_timer);
1044 }
1045
1046 static int
check_accept_rtadv(int idx)1047 check_accept_rtadv(int idx)
1048 {
1049 struct ifinfo *ifi;
1050
1051 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
1052 if (ifi->ifi_ifindex == idx)
1053 break;
1054 }
1055 if (ifi == NULL) {
1056 syslog(LOG_DEBUG,
1057 "<%s> if (idx=%d) not found. Why?",
1058 __func__, idx);
1059 return (0);
1060 }
1061 /*
1062 * RA_RECV: ND6_IFF_ACCEPT_RTADV
1063 * RA_SEND: ip6.forwarding
1064 */
1065 if (update_ifinfo_nd_flags(ifi) != 0) {
1066 syslog(LOG_ERR, "cannot get nd6 flags (idx=%d)", idx);
1067 return (0);
1068 }
1069
1070 return (ifi->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV);
1071 }
1072
1073 static void
ra_input(int len,struct nd_router_advert * nra,struct in6_pktinfo * pi,struct sockaddr_in6 * from)1074 ra_input(int len, struct nd_router_advert *nra,
1075 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
1076 {
1077 struct rainfo *rai;
1078 struct ifinfo *ifi;
1079 char ntopbuf[INET6_ADDRSTRLEN];
1080 char ifnamebuf[IFNAMSIZ];
1081 union nd_opt ndopts;
1082 const char *on_off[] = {"OFF", "ON"};
1083 uint32_t reachabletime, retranstimer, mtu;
1084 int inconsistent = 0;
1085 int error;
1086
1087 syslog(LOG_DEBUG, "<%s> RA received from %s on %s", __func__,
1088 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)),
1089 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
1090
1091 /* ND option check */
1092 memset(&ndopts, 0, sizeof(ndopts));
1093 TAILQ_INIT(&ndopts.opt_list);
1094 error = nd6_options((struct nd_opt_hdr *)(nra + 1),
1095 len - sizeof(struct nd_router_advert), &ndopts,
1096 NDOPT_FLAG_SRCLINKADDR | NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU |
1097 NDOPT_FLAG_RDNSS | NDOPT_FLAG_DNSSL);
1098 if (error) {
1099 syslog(LOG_INFO,
1100 "<%s> ND option check failed for an RA from %s on %s",
1101 __func__,
1102 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1103 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex,
1104 ifnamebuf));
1105 return;
1106 }
1107
1108 /*
1109 * RA consistency check according to RFC 4861 6.2.7
1110 */
1111 ifi = if_indextoifinfo(pi->ipi6_ifindex);
1112 if (ifi->ifi_rainfo == NULL) {
1113 syslog(LOG_INFO,
1114 "<%s> received RA from %s on non-advertising"
1115 " interface(%s)",
1116 __func__,
1117 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1118 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex,
1119 ifnamebuf));
1120 goto done;
1121 }
1122 rai = ifi->ifi_rainfo;
1123 ifi->ifi_rainput++;
1124 syslog(LOG_DEBUG, "<%s> ifi->ifi_rainput = %" PRIu64, __func__,
1125 ifi->ifi_rainput);
1126
1127 /* Cur Hop Limit value */
1128 if (nra->nd_ra_curhoplimit && rai->rai_hoplimit &&
1129 nra->nd_ra_curhoplimit != rai->rai_hoplimit) {
1130 syslog(LOG_NOTICE,
1131 "CurHopLimit inconsistent on %s:"
1132 " %d from %s, %d from us",
1133 ifi->ifi_ifname, nra->nd_ra_curhoplimit,
1134 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1135 sizeof(ntopbuf)), rai->rai_hoplimit);
1136 inconsistent++;
1137 }
1138 /* M flag */
1139 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) !=
1140 rai->rai_managedflg) {
1141 syslog(LOG_NOTICE,
1142 "M flag inconsistent on %s:"
1143 " %s from %s, %s from us",
1144 ifi->ifi_ifname, on_off[!rai->rai_managedflg],
1145 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1146 sizeof(ntopbuf)), on_off[rai->rai_managedflg]);
1147 inconsistent++;
1148 }
1149 /* O flag */
1150 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) !=
1151 rai->rai_otherflg) {
1152 syslog(LOG_NOTICE,
1153 "O flag inconsistent on %s:"
1154 " %s from %s, %s from us",
1155 ifi->ifi_ifname, on_off[!rai->rai_otherflg],
1156 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1157 sizeof(ntopbuf)), on_off[rai->rai_otherflg]);
1158 inconsistent++;
1159 }
1160 /* Reachable Time */
1161 reachabletime = ntohl(nra->nd_ra_reachable);
1162 if (reachabletime && rai->rai_reachabletime &&
1163 reachabletime != rai->rai_reachabletime) {
1164 syslog(LOG_NOTICE,
1165 "ReachableTime inconsistent on %s:"
1166 " %d from %s, %d from us",
1167 ifi->ifi_ifname, reachabletime,
1168 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1169 sizeof(ntopbuf)), rai->rai_reachabletime);
1170 inconsistent++;
1171 }
1172 /* Retrans Timer */
1173 retranstimer = ntohl(nra->nd_ra_retransmit);
1174 if (retranstimer && rai->rai_retranstimer &&
1175 retranstimer != rai->rai_retranstimer) {
1176 syslog(LOG_NOTICE,
1177 "RetranceTimer inconsistent on %s:"
1178 " %d from %s, %d from us",
1179 ifi->ifi_ifname, retranstimer,
1180 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1181 sizeof(ntopbuf)), rai->rai_retranstimer);
1182 inconsistent++;
1183 }
1184 /* Values in the MTU options */
1185 if (ndopts.opt_mtu) {
1186 mtu = ntohl(ndopts.opt_mtu->nd_opt_mtu_mtu);
1187 if (mtu && rai->rai_linkmtu && mtu != rai->rai_linkmtu) {
1188 syslog(LOG_NOTICE,
1189 "MTU option value inconsistent on %s:"
1190 " %d from %s, %d from us",
1191 ifi->ifi_ifname, mtu,
1192 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1193 sizeof(ntopbuf)), rai->rai_linkmtu);
1194 inconsistent++;
1195 }
1196 }
1197 /* Preferred and Valid Lifetimes for prefixes */
1198 {
1199 struct nd_optlist *nol;
1200
1201 if (ndopts.opt_pi)
1202 if (prefix_check(ndopts.opt_pi, rai, from))
1203 inconsistent++;
1204
1205 TAILQ_FOREACH(nol, &ndopts.opt_list, nol_next)
1206 if (prefix_check((struct nd_opt_prefix_info *)nol->nol_opt,
1207 rai, from))
1208 inconsistent++;
1209 }
1210
1211 if (inconsistent)
1212 ifi->ifi_rainconsistent++;
1213
1214 done:
1215 free_ndopts(&ndopts);
1216 return;
1217 }
1218
1219 static uint32_t
udiff(uint32_t u,uint32_t v)1220 udiff(uint32_t u, uint32_t v)
1221 {
1222 return (u >= v ? u - v : v - u);
1223 }
1224
1225 /* return a non-zero value if the received prefix is inconsitent with ours */
1226 static int
prefix_check(struct nd_opt_prefix_info * pinfo,struct rainfo * rai,struct sockaddr_in6 * from)1227 prefix_check(struct nd_opt_prefix_info *pinfo,
1228 struct rainfo *rai, struct sockaddr_in6 *from)
1229 {
1230 struct ifinfo *ifi;
1231 uint32_t preferred_time, valid_time;
1232 struct prefix *pfx;
1233 int inconsistent = 0;
1234 char ntopbuf[INET6_ADDRSTRLEN];
1235 char prefixbuf[INET6_ADDRSTRLEN];
1236 struct timespec now;
1237
1238 #if 0 /* impossible */
1239 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION)
1240 return (0);
1241 #endif
1242 ifi = rai->rai_ifinfo;
1243 /*
1244 * log if the adveritsed prefix has link-local scope(sanity check?)
1245 */
1246 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix))
1247 syslog(LOG_INFO,
1248 "<%s> link-local prefix %s/%d is advertised "
1249 "from %s on %s",
1250 __func__,
1251 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1252 sizeof(prefixbuf)),
1253 pinfo->nd_opt_pi_prefix_len,
1254 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1255 sizeof(ntopbuf)), ifi->ifi_ifname);
1256
1257 if ((pfx = find_prefix(rai, &pinfo->nd_opt_pi_prefix,
1258 pinfo->nd_opt_pi_prefix_len)) == NULL) {
1259 syslog(LOG_INFO,
1260 "<%s> prefix %s/%d from %s on %s is not in our list",
1261 __func__,
1262 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1263 sizeof(prefixbuf)),
1264 pinfo->nd_opt_pi_prefix_len,
1265 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1266 sizeof(ntopbuf)), ifi->ifi_ifname);
1267 return (0);
1268 }
1269
1270 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time);
1271 if (pfx->pfx_pltimeexpire) {
1272 /*
1273 * The lifetime is decremented in real time, so we should
1274 * compare the expiration time.
1275 * (RFC 2461 Section 6.2.7.)
1276 * XXX: can we really expect that all routers on the link
1277 * have synchronized clocks?
1278 */
1279 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1280 preferred_time += now.tv_sec;
1281
1282 if (!pfx->pfx_timer && rai->rai_clockskew &&
1283 udiff(preferred_time, pfx->pfx_pltimeexpire) > rai->rai_clockskew) {
1284 syslog(LOG_INFO,
1285 "<%s> preferred lifetime for %s/%d"
1286 " (decr. in real time) inconsistent on %s:"
1287 " %" PRIu32 " from %s, %" PRIu32 " from us",
1288 __func__,
1289 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1290 sizeof(prefixbuf)),
1291 pinfo->nd_opt_pi_prefix_len,
1292 ifi->ifi_ifname, preferred_time,
1293 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1294 sizeof(ntopbuf)), pfx->pfx_pltimeexpire);
1295 inconsistent++;
1296 }
1297 } else if (!pfx->pfx_timer && preferred_time != pfx->pfx_preflifetime)
1298 syslog(LOG_INFO,
1299 "<%s> preferred lifetime for %s/%d"
1300 " inconsistent on %s:"
1301 " %d from %s, %d from us",
1302 __func__,
1303 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1304 sizeof(prefixbuf)),
1305 pinfo->nd_opt_pi_prefix_len,
1306 ifi->ifi_ifname, preferred_time,
1307 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1308 sizeof(ntopbuf)), pfx->pfx_preflifetime);
1309
1310 valid_time = ntohl(pinfo->nd_opt_pi_valid_time);
1311 if (pfx->pfx_vltimeexpire) {
1312 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1313 valid_time += now.tv_sec;
1314
1315 if (!pfx->pfx_timer && rai->rai_clockskew &&
1316 udiff(valid_time, pfx->pfx_vltimeexpire) > rai->rai_clockskew) {
1317 syslog(LOG_INFO,
1318 "<%s> valid lifetime for %s/%d"
1319 " (decr. in real time) inconsistent on %s:"
1320 " %d from %s, %" PRIu32 " from us",
1321 __func__,
1322 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1323 sizeof(prefixbuf)),
1324 pinfo->nd_opt_pi_prefix_len,
1325 ifi->ifi_ifname, preferred_time,
1326 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1327 sizeof(ntopbuf)), pfx->pfx_vltimeexpire);
1328 inconsistent++;
1329 }
1330 } else if (!pfx->pfx_timer && valid_time != pfx->pfx_validlifetime) {
1331 syslog(LOG_INFO,
1332 "<%s> valid lifetime for %s/%d"
1333 " inconsistent on %s:"
1334 " %d from %s, %d from us",
1335 __func__,
1336 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1337 sizeof(prefixbuf)),
1338 pinfo->nd_opt_pi_prefix_len,
1339 ifi->ifi_ifname, valid_time,
1340 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1341 sizeof(ntopbuf)), pfx->pfx_validlifetime);
1342 inconsistent++;
1343 }
1344
1345 return (inconsistent);
1346 }
1347
1348 struct prefix *
find_prefix(struct rainfo * rai,struct in6_addr * prefix,int plen)1349 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen)
1350 {
1351 struct prefix *pfx;
1352 int bytelen, bitlen;
1353 char bitmask;
1354
1355 TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) {
1356 if (plen != pfx->pfx_prefixlen)
1357 continue;
1358
1359 bytelen = plen / 8;
1360 bitlen = plen % 8;
1361 bitmask = 0xff << (8 - bitlen);
1362
1363 if (memcmp((void *)prefix, (void *)&pfx->pfx_prefix, bytelen))
1364 continue;
1365
1366 if (bitlen == 0 ||
1367 ((prefix->s6_addr[bytelen] & bitmask) ==
1368 (pfx->pfx_prefix.s6_addr[bytelen] & bitmask))) {
1369 return (pfx);
1370 }
1371 }
1372
1373 return (NULL);
1374 }
1375
1376 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */
1377 int
prefix_match(struct in6_addr * p0,int plen0,struct in6_addr * p1,int plen1)1378 prefix_match(struct in6_addr *p0, int plen0,
1379 struct in6_addr *p1, int plen1)
1380 {
1381 int bytelen, bitlen;
1382 char bitmask;
1383
1384 if (plen0 < plen1)
1385 return (0);
1386
1387 bytelen = plen1 / 8;
1388 bitlen = plen1 % 8;
1389 bitmask = 0xff << (8 - bitlen);
1390
1391 if (memcmp((void *)p0, (void *)p1, bytelen))
1392 return (0);
1393
1394 if (bitlen == 0 ||
1395 ((p0->s6_addr[bytelen] & bitmask) ==
1396 (p1->s6_addr[bytelen] & bitmask))) {
1397 return (1);
1398 }
1399
1400 return (0);
1401 }
1402
1403 static int
nd6_options(struct nd_opt_hdr * hdr,int limit,union nd_opt * ndopts,uint32_t optflags)1404 nd6_options(struct nd_opt_hdr *hdr, int limit,
1405 union nd_opt *ndopts, uint32_t optflags)
1406 {
1407 int optlen = 0;
1408
1409 for (; limit > 0; limit -= optlen) {
1410 if ((size_t)limit < sizeof(struct nd_opt_hdr)) {
1411 syslog(LOG_INFO, "<%s> short option header", __func__);
1412 goto bad;
1413 }
1414
1415 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen);
1416 if (hdr->nd_opt_len == 0) {
1417 syslog(LOG_INFO,
1418 "<%s> bad ND option length(0) (type = %d)",
1419 __func__, hdr->nd_opt_type);
1420 goto bad;
1421 }
1422 optlen = hdr->nd_opt_len << 3;
1423 if (optlen > limit) {
1424 syslog(LOG_INFO, "<%s> short option", __func__);
1425 goto bad;
1426 }
1427
1428 if (hdr->nd_opt_type > ND_OPT_MTU &&
1429 hdr->nd_opt_type != ND_OPT_RDNSS &&
1430 hdr->nd_opt_type != ND_OPT_DNSSL) {
1431 syslog(LOG_INFO, "<%s> unknown ND option(type %d)",
1432 __func__, hdr->nd_opt_type);
1433 continue;
1434 }
1435
1436 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) {
1437 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)",
1438 __func__, hdr->nd_opt_type);
1439 continue;
1440 }
1441
1442 /*
1443 * Option length check. Do it here for all fixed-length
1444 * options.
1445 */
1446 switch (hdr->nd_opt_type) {
1447 case ND_OPT_MTU:
1448 if (optlen == sizeof(struct nd_opt_mtu))
1449 break;
1450 goto skip;
1451 case ND_OPT_RDNSS:
1452 if (optlen >= 24 &&
1453 (optlen - sizeof(struct nd_opt_rdnss)) % 16 == 0)
1454 break;
1455 goto skip;
1456 case ND_OPT_DNSSL:
1457 if (optlen >= 16 &&
1458 (optlen - sizeof(struct nd_opt_dnssl)) % 8 == 0)
1459 break;
1460 goto skip;
1461 case ND_OPT_PREFIX_INFORMATION:
1462 if (optlen == sizeof(struct nd_opt_prefix_info))
1463 break;
1464 skip:
1465 syslog(LOG_INFO, "<%s> invalid option length",
1466 __func__);
1467 continue;
1468 }
1469
1470 switch (hdr->nd_opt_type) {
1471 case ND_OPT_TARGET_LINKADDR:
1472 case ND_OPT_REDIRECTED_HEADER:
1473 case ND_OPT_RDNSS:
1474 case ND_OPT_DNSSL:
1475 break; /* we don't care about these options */
1476 case ND_OPT_SOURCE_LINKADDR:
1477 case ND_OPT_MTU:
1478 if (ndopts->opt_array[hdr->nd_opt_type]) {
1479 syslog(LOG_INFO,
1480 "<%s> duplicated ND option (type = %d)",
1481 __func__, hdr->nd_opt_type);
1482 }
1483 ndopts->opt_array[hdr->nd_opt_type] = hdr;
1484 break;
1485 case ND_OPT_PREFIX_INFORMATION:
1486 {
1487 struct nd_optlist *nol;
1488
1489 if (ndopts->opt_pi == 0) {
1490 ndopts->opt_pi =
1491 (struct nd_opt_prefix_info *)hdr;
1492 continue;
1493 }
1494 nol = malloc(sizeof(*nol));
1495 if (nol == NULL) {
1496 syslog(LOG_ERR, "<%s> can't allocate memory",
1497 __func__);
1498 goto bad;
1499 }
1500 nol->nol_opt = hdr;
1501 TAILQ_INSERT_TAIL(&(ndopts->opt_list), nol, nol_next);
1502
1503 break;
1504 }
1505 default: /* impossible */
1506 break;
1507 }
1508 }
1509
1510 return (0);
1511
1512 bad:
1513 free_ndopts(ndopts);
1514
1515 return (-1);
1516 }
1517
1518 static void
free_ndopts(union nd_opt * ndopts)1519 free_ndopts(union nd_opt *ndopts)
1520 {
1521 struct nd_optlist *nol;
1522
1523 while ((nol = TAILQ_FIRST(&ndopts->opt_list)) != NULL) {
1524 TAILQ_REMOVE(&ndopts->opt_list, nol, nol_next);
1525 free(nol);
1526 }
1527 }
1528
1529 void
sock_open(struct sockinfo * s)1530 sock_open(struct sockinfo *s)
1531 {
1532 struct icmp6_filter filt;
1533 int on;
1534 /* XXX: should be max MTU attached to the node */
1535 static char answer[1500];
1536
1537 syslog(LOG_DEBUG, "<%s> enter", __func__);
1538
1539 if (s == NULL) {
1540 syslog(LOG_ERR, "<%s> internal error", __func__);
1541 exit(1);
1542 }
1543 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1544 CMSG_SPACE(sizeof(int));
1545 rcvcmsgbuf = (char *)malloc(rcvcmsgbuflen);
1546 if (rcvcmsgbuf == NULL) {
1547 syslog(LOG_ERR, "<%s> not enough core", __func__);
1548 exit(1);
1549 }
1550
1551 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1552 CMSG_SPACE(sizeof(int));
1553 sndcmsgbuf = (char *)malloc(sndcmsgbuflen);
1554 if (sndcmsgbuf == NULL) {
1555 syslog(LOG_ERR, "<%s> not enough core", __func__);
1556 exit(1);
1557 }
1558
1559 if ((s->si_fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
1560 syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno));
1561 exit(1);
1562 }
1563 /* specify to tell receiving interface */
1564 on = 1;
1565 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
1566 sizeof(on)) < 0) {
1567 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", __func__,
1568 strerror(errno));
1569 exit(1);
1570 }
1571 on = 1;
1572 /* specify to tell value of hoplimit field of received IP6 hdr */
1573 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
1574 sizeof(on)) < 0) {
1575 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", __func__,
1576 strerror(errno));
1577 exit(1);
1578 }
1579 ICMP6_FILTER_SETBLOCKALL(&filt);
1580 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt);
1581 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
1582 if (mcastif != NULL)
1583 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt);
1584
1585 if (setsockopt(s->si_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
1586 sizeof(filt)) < 0) {
1587 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s",
1588 __func__, strerror(errno));
1589 exit(1);
1590 }
1591
1592 /* initialize msghdr for receiving packets */
1593 rcviov[0].iov_base = (caddr_t)answer;
1594 rcviov[0].iov_len = sizeof(answer);
1595 rcvmhdr.msg_name = (caddr_t)&rcvfrom;
1596 rcvmhdr.msg_namelen = sizeof(rcvfrom);
1597 rcvmhdr.msg_iov = rcviov;
1598 rcvmhdr.msg_iovlen = 1;
1599 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
1600 rcvmhdr.msg_controllen = rcvcmsgbuflen;
1601
1602 /* initialize msghdr for sending packets */
1603 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
1604 sndmhdr.msg_iov = sndiov;
1605 sndmhdr.msg_iovlen = 1;
1606 sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
1607 sndmhdr.msg_controllen = sndcmsgbuflen;
1608
1609 return;
1610 }
1611
1612 /* open a routing socket to watch the routing table */
1613 static void
rtsock_open(struct sockinfo * s)1614 rtsock_open(struct sockinfo *s)
1615 {
1616 if (s == NULL) {
1617 syslog(LOG_ERR, "<%s> internal error", __func__);
1618 exit(1);
1619 }
1620 if ((s->si_fd = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) {
1621 syslog(LOG_ERR,
1622 "<%s> socket: %s", __func__, strerror(errno));
1623 exit(1);
1624 }
1625 }
1626
1627 struct ifinfo *
if_indextoifinfo(int idx)1628 if_indextoifinfo(int idx)
1629 {
1630 struct ifinfo *ifi;
1631 char name0[IFNAMSIZ];
1632
1633 /* Check if the interface has a valid name or not. */
1634 if (if_indextoname(idx, name0) == NULL)
1635 return (NULL);
1636
1637 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
1638 if (ifi->ifi_ifindex == idx)
1639 return (ifi);
1640 }
1641
1642 if (ifi != NULL)
1643 syslog(LOG_DEBUG, "<%s> ifi found (idx=%d)",
1644 __func__, idx);
1645 else
1646 syslog(LOG_DEBUG, "<%s> ifi not found (idx=%d)",
1647 __func__, idx);
1648
1649 return (NULL); /* search failed */
1650 }
1651
1652 void
ra_output(struct ifinfo * ifi)1653 ra_output(struct ifinfo *ifi)
1654 {
1655 int i;
1656 struct cmsghdr *cm;
1657 struct in6_pktinfo *pi;
1658 struct soliciter *sol;
1659 struct rainfo *rai;
1660
1661 switch (ifi->ifi_state) {
1662 case IFI_STATE_CONFIGURED:
1663 rai = ifi->ifi_rainfo;
1664 break;
1665 case IFI_STATE_TRANSITIVE:
1666 rai = ifi->ifi_rainfo_trans;
1667 break;
1668 case IFI_STATE_UNCONFIGURED:
1669 syslog(LOG_DEBUG, "<%s> %s is unconfigured. "
1670 "Skip sending RAs.",
1671 __func__, ifi->ifi_ifname);
1672 return;
1673 default:
1674 rai = NULL;
1675 }
1676 if (rai == NULL) {
1677 syslog(LOG_DEBUG, "<%s> rainfo is NULL on %s."
1678 "Skip sending RAs.",
1679 __func__, ifi->ifi_ifname);
1680 return;
1681 }
1682 if (!(ifi->ifi_flags & IFF_UP)) {
1683 syslog(LOG_DEBUG, "<%s> %s is not up. "
1684 "Skip sending RAs.",
1685 __func__, ifi->ifi_ifname);
1686 return;
1687 }
1688 /*
1689 * Check lifetime, ACCEPT_RTADV flag, and ip6.forwarding.
1690 *
1691 * (lifetime == 0) = output
1692 * (lifetime != 0 && (check_accept_rtadv()) = no output
1693 *
1694 * Basically, hosts MUST NOT send Router Advertisement
1695 * messages at any time (RFC 4861, Section 6.2.3). However, it
1696 * would sometimes be useful to allow hosts to advertise some
1697 * parameters such as prefix information and link MTU. Thus,
1698 * we allow hosts to invoke rtadvd only when router lifetime
1699 * (on every advertising interface) is explicitly set
1700 * zero. (see also the above section)
1701 */
1702 syslog(LOG_DEBUG,
1703 "<%s> check lifetime=%d, ACCEPT_RTADV=%d, ip6.forwarding=%d "
1704 "on %s", __func__,
1705 rai->rai_lifetime,
1706 check_accept_rtadv(ifi->ifi_ifindex),
1707 getinet6sysctl(IPV6CTL_FORWARDING),
1708 ifi->ifi_ifname);
1709
1710 if (rai->rai_lifetime != 0) {
1711 if (getinet6sysctl(IPV6CTL_FORWARDING) == 0) {
1712 syslog(LOG_ERR,
1713 "non-zero lifetime RA "
1714 "but net.inet6.ip6.forwarding=0. "
1715 "Ignored.");
1716 return;
1717 }
1718 if (check_accept_rtadv(ifi->ifi_ifindex)) {
1719 syslog(LOG_ERR,
1720 "non-zero lifetime RA "
1721 "on RA receiving interface %s."
1722 " Ignored.", ifi->ifi_ifname);
1723 return;
1724 }
1725 }
1726
1727 make_packet(rai); /* XXX: inefficient */
1728
1729 sndmhdr.msg_name = (caddr_t)&sin6_linklocal_allnodes;
1730 sndmhdr.msg_iov[0].iov_base = (caddr_t)rai->rai_ra_data;
1731 sndmhdr.msg_iov[0].iov_len = rai->rai_ra_datalen;
1732
1733 cm = CMSG_FIRSTHDR(&sndmhdr);
1734 /* specify the outgoing interface */
1735 cm->cmsg_level = IPPROTO_IPV6;
1736 cm->cmsg_type = IPV6_PKTINFO;
1737 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
1738 pi = (struct in6_pktinfo *)CMSG_DATA(cm);
1739 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/
1740 pi->ipi6_ifindex = ifi->ifi_ifindex;
1741
1742 /* specify the hop limit of the packet */
1743 {
1744 int hoplimit = 255;
1745
1746 cm = CMSG_NXTHDR(&sndmhdr, cm);
1747 cm->cmsg_level = IPPROTO_IPV6;
1748 cm->cmsg_type = IPV6_HOPLIMIT;
1749 cm->cmsg_len = CMSG_LEN(sizeof(int));
1750 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
1751 }
1752
1753 syslog(LOG_DEBUG,
1754 "<%s> send RA on %s, # of RS waitings = %d",
1755 __func__, ifi->ifi_ifname, ifi->ifi_rs_waitcount);
1756
1757 i = sendmsg(sock.si_fd, &sndmhdr, 0);
1758
1759 if (i < 0 || (size_t)i != rai->rai_ra_datalen) {
1760 if (i < 0) {
1761 syslog(LOG_ERR, "<%s> sendmsg on %s: %s",
1762 __func__, ifi->ifi_ifname,
1763 strerror(errno));
1764 }
1765 }
1766
1767 /*
1768 * unicast advertisements
1769 * XXX commented out. reason: though spec does not forbit it, unicast
1770 * advert does not really help
1771 */
1772 while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) {
1773 TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next);
1774 free(sol);
1775 }
1776
1777 /* update timestamp */
1778 clock_gettime(CLOCK_MONOTONIC_FAST, &ifi->ifi_ra_lastsent);
1779
1780 /* update counter */
1781 ifi->ifi_rs_waitcount = 0;
1782 ifi->ifi_raoutput++;
1783
1784 switch (ifi->ifi_state) {
1785 case IFI_STATE_CONFIGURED:
1786 if (ifi->ifi_burstcount > 0)
1787 ifi->ifi_burstcount--;
1788 break;
1789 case IFI_STATE_TRANSITIVE:
1790 ifi->ifi_burstcount--;
1791 if (ifi->ifi_burstcount == 0) {
1792 if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) {
1793 /* Initial burst finished. */
1794 if (ifi->ifi_rainfo_trans != NULL)
1795 ifi->ifi_rainfo_trans = NULL;
1796 }
1797
1798 /* Remove burst RA information */
1799 if (ifi->ifi_rainfo_trans != NULL) {
1800 rm_rainfo(ifi->ifi_rainfo_trans);
1801 ifi->ifi_rainfo_trans = NULL;
1802 }
1803
1804 if (ifi->ifi_rainfo != NULL) {
1805 /*
1806 * TRANSITIVE -> CONFIGURED
1807 *
1808 * After initial burst or transition from
1809 * one configuration to another,
1810 * ifi_rainfo always points to the next RA
1811 * information.
1812 */
1813 ifi->ifi_state = IFI_STATE_CONFIGURED;
1814 syslog(LOG_DEBUG,
1815 "<%s> ifname=%s marked as "
1816 "CONFIGURED.", __func__,
1817 ifi->ifi_ifname);
1818 } else {
1819 /*
1820 * TRANSITIVE -> UNCONFIGURED
1821 *
1822 * If ifi_rainfo points to NULL, this
1823 * interface is shutting down.
1824 *
1825 */
1826 int error;
1827
1828 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
1829 syslog(LOG_DEBUG,
1830 "<%s> ifname=%s marked as "
1831 "UNCONFIGURED.", __func__,
1832 ifi->ifi_ifname);
1833 error = sock_mc_leave(&sock,
1834 ifi->ifi_ifindex);
1835 if (error)
1836 exit(1);
1837 }
1838 }
1839 break;
1840 }
1841 }
1842
1843 /* process RA timer */
1844 struct rtadvd_timer *
ra_timeout(void * arg)1845 ra_timeout(void *arg)
1846 {
1847 struct ifinfo *ifi;
1848
1849 ifi = (struct ifinfo *)arg;
1850 syslog(LOG_DEBUG, "<%s> RA timer on %s is expired",
1851 __func__, ifi->ifi_ifname);
1852
1853 ra_output(ifi);
1854
1855 return (ifi->ifi_ra_timer);
1856 }
1857
1858 /* update RA timer */
1859 void
ra_timer_update(void * arg,struct timespec * tm)1860 ra_timer_update(void *arg, struct timespec *tm)
1861 {
1862 uint16_t interval;
1863 struct rainfo *rai;
1864 struct ifinfo *ifi;
1865
1866 ifi = (struct ifinfo *)arg;
1867 rai = ifi->ifi_rainfo;
1868 interval = 0;
1869
1870 switch (ifi->ifi_state) {
1871 case IFI_STATE_UNCONFIGURED:
1872 return;
1873 break;
1874 case IFI_STATE_CONFIGURED:
1875 /*
1876 * Whenever a multicast advertisement is sent from
1877 * an interface, the timer is reset to a
1878 * uniformly-distributed random value between the
1879 * interface's configured MinRtrAdvInterval and
1880 * MaxRtrAdvInterval (RFC4861 6.2.4).
1881 */
1882 interval = rai->rai_mininterval;
1883 #ifdef HAVE_ARC4RANDOM
1884 interval += arc4random_uniform(rai->rai_maxinterval -
1885 rai->rai_mininterval);
1886 #else
1887 interval += random() % (rai->rai_maxinterval -
1888 rai->rai_mininterval);
1889 #endif
1890 break;
1891 case IFI_STATE_TRANSITIVE:
1892 /*
1893 * For the first few advertisements (up to
1894 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen
1895 * interval is greater than
1896 * MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer SHOULD be
1897 * set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. (RFC
1898 * 4861 6.2.4)
1899 *
1900 * In such cases, the router SHOULD transmit one or more
1901 * (but not more than MAX_FINAL_RTR_ADVERTISEMENTS) final
1902 * multicast Router Advertisements on the interface with a
1903 * Router Lifetime field of zero. (RFC 4861 6.2.5)
1904 */
1905 interval = ifi->ifi_burstinterval;
1906 break;
1907 }
1908
1909 tm->tv_sec = interval;
1910 tm->tv_nsec = 0;
1911
1912 syslog(LOG_DEBUG,
1913 "<%s> RA timer on %s is set to %ld:%ld",
1914 __func__, ifi->ifi_ifname,
1915 (long int)tm->tv_sec, (long int)tm->tv_nsec / 1000);
1916
1917 return;
1918 }
1919