1 /* $KAME: rtadvd.c,v 1.82 2003/08/05 12:34:23 itojun Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-3-Clause
5 *
6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7 * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org>
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the project nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/param.h>
36 #include <sys/ioctl.h>
37 #include <sys/socket.h>
38 #include <sys/uio.h>
39 #include <sys/queue.h>
40 #include <sys/stat.h>
41 #include <sys/sysctl.h>
42
43 #include <net/if.h>
44 #include <net/if_types.h>
45 #include <net/if_media.h>
46 #include <net/if_dl.h>
47 #include <net/route.h>
48 #include <netinet/in.h>
49 #include <netinet/ip6.h>
50 #include <netinet6/ip6_var.h>
51 #include <netinet/icmp6.h>
52
53 #include <arpa/inet.h>
54
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 #define NDOPT_FLAG_PREF64 (1 << 7)
141
142 static uint32_t ndopt_flags[] = {
143 [ND_OPT_SOURCE_LINKADDR] = NDOPT_FLAG_SRCLINKADDR,
144 [ND_OPT_TARGET_LINKADDR] = NDOPT_FLAG_TGTLINKADDR,
145 [ND_OPT_PREFIX_INFORMATION] = NDOPT_FLAG_PREFIXINFO,
146 [ND_OPT_REDIRECTED_HEADER] = NDOPT_FLAG_RDHDR,
147 [ND_OPT_MTU] = NDOPT_FLAG_MTU,
148 [ND_OPT_RDNSS] = NDOPT_FLAG_RDNSS,
149 [ND_OPT_DNSSL] = NDOPT_FLAG_DNSSL,
150 [ND_OPT_PREF64] = NDOPT_FLAG_PREF64,
151 };
152
153 static void rtadvd_shutdown(void);
154 static void sock_open(struct sockinfo *);
155 static void rtsock_open(struct sockinfo *);
156 static void rtadvd_input(struct sockinfo *);
157 static void rs_input(int, struct nd_router_solicit *,
158 struct in6_pktinfo *, struct sockaddr_in6 *);
159 static void ra_input(int, struct nd_router_advert *,
160 struct in6_pktinfo *, struct sockaddr_in6 *);
161 static int prefix_check(struct nd_opt_prefix_info *, struct rainfo *,
162 struct sockaddr_in6 *);
163 static int nd6_options(struct nd_opt_hdr *, int,
164 union nd_opt *, uint32_t);
165 static void free_ndopts(union nd_opt *);
166 static void rtmsg_input(struct sockinfo *);
167 static void set_short_delay(struct ifinfo *);
168 static int check_accept_rtadv(int);
169
170 static void
usage(void)171 usage(void)
172 {
173
174 fprintf(stderr, "usage: rtadvd [-dDfRs] "
175 "[-c configfile] [-C ctlsock] [-M ifname] [-p pidfile]\n");
176 exit(1);
177 }
178
179 int
main(int argc,char * argv[])180 main(int argc, char *argv[])
181 {
182 struct pollfd set[PFD_MAX];
183 struct timespec *timeout;
184 int i, ch;
185 int fflag = 0, logopt;
186 int error;
187 pid_t pid, otherpid;
188
189 /* get command line options and arguments */
190 while ((ch = getopt(argc, argv, "c:C:dDfhM:p:Rs")) != -1) {
191 switch (ch) {
192 case 'c':
193 conffile = optarg;
194 break;
195 case 'C':
196 ctrlsock.si_name = optarg;
197 break;
198 case 'd':
199 dflag++;
200 break;
201 case 'D':
202 dflag += 3;
203 break;
204 case 'f':
205 fflag = 1;
206 break;
207 case 'M':
208 mcastif = optarg;
209 break;
210 case 'R':
211 fprintf(stderr, "rtadvd: "
212 "the -R option is currently ignored.\n");
213 /* accept_rr = 1; */
214 /* run anyway... */
215 break;
216 case 's':
217 sflag = 1;
218 break;
219 case 'p':
220 pidfilename = optarg;
221 break;
222 default:
223 usage();
224 }
225 }
226 argc -= optind;
227 argv += optind;
228
229 logopt = LOG_NDELAY | LOG_PID;
230 if (fflag)
231 logopt |= LOG_PERROR;
232 openlog("rtadvd", logopt, LOG_DAEMON);
233
234 /* set log level */
235 if (dflag > 2)
236 (void)setlogmask(LOG_UPTO(LOG_DEBUG));
237 else if (dflag > 1)
238 (void)setlogmask(LOG_UPTO(LOG_INFO));
239 else if (dflag > 0)
240 (void)setlogmask(LOG_UPTO(LOG_NOTICE));
241 else
242 (void)setlogmask(LOG_UPTO(LOG_ERR));
243
244 /* timer initialization */
245 rtadvd_timer_init();
246
247 pfh = pidfile_open(pidfilename, 0600, &otherpid);
248 if (pfh == NULL) {
249 if (errno == EEXIST)
250 errx(1, "%s already running, pid: %d",
251 getprogname(), otherpid);
252 syslog(LOG_ERR,
253 "failed to open the pid file %s, run anyway.",
254 pidfilename);
255 }
256 if (!fflag)
257 daemon(1, 0);
258
259 sock_open(&sock);
260
261 update_ifinfo(&ifilist, UPDATE_IFINFO_ALL);
262 for (i = 0; i < argc; i++)
263 update_persist_ifinfo(&ifilist, argv[i]);
264
265 csock_open(&ctrlsock, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
266 if (ctrlsock.si_fd == -1) {
267 syslog(LOG_ERR, "cannot open control socket: %s",
268 strerror(errno));
269 exit(1);
270 }
271
272 /* record the current PID */
273 pid = getpid();
274 pidfile_write(pfh);
275
276 set[PFD_RAWSOCK].fd = sock.si_fd;
277 set[PFD_RAWSOCK].events = POLLIN;
278 if (sflag == 0) {
279 rtsock_open(&rtsock);
280 set[PFD_RTSOCK].fd = rtsock.si_fd;
281 set[PFD_RTSOCK].events = POLLIN;
282 } else
283 set[PFD_RTSOCK].fd = -1;
284 set[PFD_CSOCK].fd = ctrlsock.si_fd;
285 set[PFD_CSOCK].events = POLLIN;
286 signal(SIGTERM, set_do_shutdown);
287 signal(SIGINT, set_do_shutdown);
288 signal(SIGHUP, set_do_reload);
289
290 error = csock_listen(&ctrlsock);
291 if (error) {
292 syslog(LOG_ERR, "cannot listen control socket: %s",
293 strerror(errno));
294 exit(1);
295 }
296
297 /* load configuration file */
298 set_do_reload(0);
299
300 while (1) {
301 if (is_do_shutdown())
302 rtadvd_shutdown();
303
304 if (is_do_reload()) {
305 loadconfig_ifname(reload_ifname());
306 if (reload_ifname() == NULL)
307 syslog(LOG_INFO,
308 "configuration file reloaded.");
309 else
310 syslog(LOG_INFO,
311 "configuration file for %s reloaded.",
312 reload_ifname());
313 reset_do_reload();
314 }
315
316 /* timeout handler update for active interfaces */
317 rtadvd_update_timeout_handler();
318
319 /* timer expiration check and reset the timer */
320 timeout = rtadvd_check_timer();
321
322 if (timeout != NULL) {
323 syslog(LOG_DEBUG,
324 "<%s> set timer to %ld:%ld. waiting for "
325 "inputs or timeout", __func__,
326 (long int)timeout->tv_sec,
327 (long int)timeout->tv_nsec / 1000);
328 } else {
329 syslog(LOG_DEBUG,
330 "<%s> there's no timer. waiting for inputs",
331 __func__);
332 }
333 if ((i = poll(set, nitems(set),
334 timeout ? (timeout->tv_sec * 1000 +
335 timeout->tv_nsec / 1000 / 1000) : INFTIM)) < 0) {
336
337 /* EINTR would occur if a signal was delivered */
338 if (errno != EINTR)
339 syslog(LOG_ERR, "poll() failed: %s",
340 strerror(errno));
341 continue;
342 }
343 if (i == 0) /* timeout */
344 continue;
345 if (rtsock.si_fd != -1 && set[PFD_RTSOCK].revents & POLLIN)
346 rtmsg_input(&rtsock);
347
348 if (set[PFD_RAWSOCK].revents & POLLIN)
349 rtadvd_input(&sock);
350
351 if (set[PFD_CSOCK].revents & POLLIN) {
352 int fd;
353
354 fd = csock_accept(&ctrlsock);
355 if (fd == -1)
356 syslog(LOG_ERR,
357 "cannot accept() control socket: %s",
358 strerror(errno));
359 else {
360 cm_handler_server(fd);
361 close(fd);
362 }
363 }
364 }
365 exit(0); /* NOTREACHED */
366 }
367
368 static void
rtadvd_shutdown(void)369 rtadvd_shutdown(void)
370 {
371 struct ifinfo *ifi;
372 struct rainfo *rai;
373 struct rdnss *rdn;
374 struct dnssl *dns;
375
376 if (wait_shutdown) {
377 syslog(LOG_INFO,
378 "waiting expiration of the all RA timers.");
379
380 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
381 /*
382 * Ignore !IFF_UP interfaces in waiting for shutdown.
383 */
384 if (!(ifi->ifi_flags & IFF_UP) &&
385 ifi->ifi_ra_timer != NULL) {
386 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
387 rtadvd_remove_timer(ifi->ifi_ra_timer);
388 ifi->ifi_ra_timer = NULL;
389 syslog(LOG_DEBUG, "<%s> %s(idx=%d) is down. "
390 "Timer removed and marked as UNCONFIGURED.",
391 __func__, ifi->ifi_ifname,
392 ifi->ifi_ifindex);
393 }
394 }
395 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
396 if (ifi->ifi_ra_timer != NULL)
397 break;
398 }
399 if (ifi == NULL) {
400 syslog(LOG_NOTICE, "gracefully terminated.");
401 exit(0);
402 }
403
404 sleep(1);
405 return;
406 }
407
408 syslog(LOG_DEBUG, "<%s> cease to be an advertising router",
409 __func__);
410
411 wait_shutdown = 1;
412
413 TAILQ_FOREACH(rai, &railist, rai_next) {
414 rai->rai_lifetime = 0;
415 TAILQ_FOREACH(rdn, &rai->rai_rdnss, rd_next)
416 rdn->rd_ltime = 0;
417 TAILQ_FOREACH(dns, &rai->rai_dnssl, dn_next)
418 dns->dn_ltime = 0;
419 }
420 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
421 if (!ifi->ifi_persist)
422 continue;
423 if (ifi->ifi_state == IFI_STATE_UNCONFIGURED)
424 continue;
425 if (ifi->ifi_ra_timer == NULL)
426 continue;
427 if (ifi->ifi_ra_lastsent.tv_sec == 0 &&
428 ifi->ifi_ra_lastsent.tv_nsec == 0 &&
429 ifi->ifi_ra_timer != NULL) {
430 /*
431 * When RA configured but never sent,
432 * ignore the IF immediately.
433 */
434 rtadvd_remove_timer(ifi->ifi_ra_timer);
435 ifi->ifi_ra_timer = NULL;
436 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
437 continue;
438 }
439
440 ifi->ifi_state = IFI_STATE_TRANSITIVE;
441
442 /* Mark as the shut-down state. */
443 ifi->ifi_rainfo_trans = ifi->ifi_rainfo;
444 ifi->ifi_rainfo = NULL;
445
446 ifi->ifi_burstcount = MAX_FINAL_RTR_ADVERTISEMENTS;
447 ifi->ifi_burstinterval = MIN_DELAY_BETWEEN_RAS;
448
449 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
450 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
451 ifi->ifi_ra_timer);
452 }
453 syslog(LOG_NOTICE, "final RA transmission started.");
454
455 pidfile_remove(pfh);
456 csock_close(&ctrlsock);
457 }
458
459 static void
rtmsg_input(struct sockinfo * s)460 rtmsg_input(struct sockinfo *s)
461 {
462 int n, type, ifindex = 0, plen;
463 size_t len;
464 char msg[2048], *next, *lim;
465 char ifname[IFNAMSIZ];
466 struct if_announcemsghdr *ifan;
467 struct rt_msghdr *rtm;
468 struct prefix *pfx;
469 struct rainfo *rai;
470 struct in6_addr *addr;
471 struct ifinfo *ifi;
472 char addrbuf[INET6_ADDRSTRLEN];
473 int prefixchange = 0;
474
475 if (s == NULL) {
476 syslog(LOG_ERR, "<%s> internal error", __func__);
477 exit(1);
478 }
479 n = read(s->si_fd, msg, sizeof(msg));
480 rtm = (struct rt_msghdr *)msg;
481 syslog(LOG_DEBUG, "<%s> received a routing message "
482 "(type = %d, len = %d)", __func__, rtm->rtm_type, n);
483
484 if (n > rtm->rtm_msglen) {
485 /*
486 * This usually won't happen for messages received on
487 * a routing socket.
488 */
489 syslog(LOG_DEBUG,
490 "<%s> received data length is larger than "
491 "1st routing message len. multiple messages? "
492 "read %d bytes, but 1st msg len = %d",
493 __func__, n, rtm->rtm_msglen);
494 #if 0
495 /* adjust length */
496 n = rtm->rtm_msglen;
497 #endif
498 }
499
500 lim = msg + n;
501 for (next = msg; next < lim; next += len) {
502 int oldifflags;
503
504 next = get_next_msg(next, lim, 0, &len,
505 RTADV_TYPE2BITMASK(RTM_ADD) |
506 RTADV_TYPE2BITMASK(RTM_DELETE) |
507 RTADV_TYPE2BITMASK(RTM_NEWADDR) |
508 RTADV_TYPE2BITMASK(RTM_DELADDR) |
509 RTADV_TYPE2BITMASK(RTM_IFINFO) |
510 RTADV_TYPE2BITMASK(RTM_IFANNOUNCE));
511 if (len == 0)
512 break;
513 type = ((struct rt_msghdr *)next)->rtm_type;
514 switch (type) {
515 case RTM_ADD:
516 case RTM_DELETE:
517 ifindex = get_rtm_ifindex(next);
518 break;
519 case RTM_NEWADDR:
520 case RTM_DELADDR:
521 ifindex = (int)((struct ifa_msghdr *)next)->ifam_index;
522 break;
523 case RTM_IFINFO:
524 ifindex = (int)((struct if_msghdr *)next)->ifm_index;
525 break;
526 case RTM_IFANNOUNCE:
527 ifan = (struct if_announcemsghdr *)next;
528 switch (ifan->ifan_what) {
529 case IFAN_ARRIVAL:
530 case IFAN_DEPARTURE:
531 break;
532 default:
533 syslog(LOG_DEBUG,
534 "<%s:%d> unknown ifan msg (ifan_what=%d)",
535 __func__, __LINE__, ifan->ifan_what);
536 continue;
537 }
538
539 syslog(LOG_DEBUG, "<%s>: if_announcemsg (idx=%d:%d)",
540 __func__, ifan->ifan_index, ifan->ifan_what);
541 switch (ifan->ifan_what) {
542 case IFAN_ARRIVAL:
543 syslog(LOG_NOTICE,
544 "interface added (idx=%d)",
545 ifan->ifan_index);
546 update_ifinfo(&ifilist, ifan->ifan_index);
547 loadconfig_index(ifan->ifan_index);
548 break;
549 case IFAN_DEPARTURE:
550 syslog(LOG_NOTICE,
551 "interface removed (idx=%d)",
552 ifan->ifan_index);
553 rm_ifinfo_index(ifan->ifan_index);
554
555 /* Clear ifi_ifindex */
556 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
557 if (ifi->ifi_ifindex
558 == ifan->ifan_index) {
559 ifi->ifi_ifindex = 0;
560 break;
561 }
562 }
563 update_ifinfo(&ifilist, ifan->ifan_index);
564 break;
565 }
566 continue;
567 default:
568 /* should not reach here */
569 syslog(LOG_DEBUG,
570 "<%s:%d> unknown rtmsg %d on %s",
571 __func__, __LINE__, type,
572 if_indextoname(ifindex, ifname));
573 continue;
574 }
575 ifi = if_indextoifinfo(ifindex);
576 if (ifi == NULL) {
577 syslog(LOG_DEBUG,
578 "<%s> ifinfo not found for idx=%d. Why?",
579 __func__, ifindex);
580 continue;
581 }
582 rai = ifi->ifi_rainfo;
583 if (rai == NULL) {
584 syslog(LOG_DEBUG,
585 "<%s> route changed on "
586 "non advertising interface(%s)",
587 __func__, ifi->ifi_ifname);
588 continue;
589 }
590
591 oldifflags = ifi->ifi_flags;
592 /* init ifflags because it may have changed */
593 update_ifinfo(&ifilist, ifindex);
594
595 switch (type) {
596 case RTM_ADD:
597 if (sflag)
598 break; /* we aren't interested in prefixes */
599
600 addr = get_addr(msg);
601 plen = get_prefixlen(msg);
602 /* sanity check for plen */
603 /* as RFC2373, prefixlen is at least 4 */
604 if (plen < 4 || plen > 127) {
605 syslog(LOG_INFO, "<%s> new interface route's"
606 "plen %d is invalid for a prefix",
607 __func__, plen);
608 break;
609 }
610 pfx = find_prefix(rai, addr, plen);
611 if (pfx) {
612 if (pfx->pfx_timer) {
613 /*
614 * If the prefix has been invalidated,
615 * make it available again.
616 */
617 update_prefix(pfx);
618 prefixchange = 1;
619 } else
620 syslog(LOG_DEBUG,
621 "<%s> new prefix(%s/%d) "
622 "added on %s, "
623 "but it was already in list",
624 __func__,
625 inet_ntop(AF_INET6, addr,
626 (char *)addrbuf,
627 sizeof(addrbuf)),
628 plen, ifi->ifi_ifname);
629 break;
630 }
631 make_prefix(rai, ifindex, addr, plen);
632 prefixchange = 1;
633 break;
634 case RTM_DELETE:
635 if (sflag)
636 break;
637
638 addr = get_addr(msg);
639 plen = get_prefixlen(msg);
640 /* sanity check for plen */
641 /* as RFC2373, prefixlen is at least 4 */
642 if (plen < 4 || plen > 127) {
643 syslog(LOG_INFO,
644 "<%s> deleted interface route's "
645 "plen %d is invalid for a prefix",
646 __func__, plen);
647 break;
648 }
649 pfx = find_prefix(rai, addr, plen);
650 if (pfx == NULL) {
651 syslog(LOG_DEBUG,
652 "<%s> prefix(%s/%d) was deleted on %s, "
653 "but it was not in list",
654 __func__, inet_ntop(AF_INET6, addr,
655 (char *)addrbuf, sizeof(addrbuf)),
656 plen, ifi->ifi_ifname);
657 break;
658 }
659 invalidate_prefix(pfx);
660 prefixchange = 1;
661 break;
662 case RTM_NEWADDR:
663 case RTM_DELADDR:
664 case RTM_IFINFO:
665 break;
666 default:
667 /* should not reach here */
668 syslog(LOG_DEBUG,
669 "<%s:%d> unknown rtmsg %d on %s",
670 __func__, __LINE__, type,
671 if_indextoname(ifindex, ifname));
672 return;
673 }
674
675 /* check if an interface flag is changed */
676 if ((oldifflags & IFF_UP) && /* UP to DOWN */
677 !(ifi->ifi_flags & IFF_UP)) {
678 syslog(LOG_NOTICE,
679 "<interface %s becomes down. stop timer.",
680 ifi->ifi_ifname);
681 rtadvd_remove_timer(ifi->ifi_ra_timer);
682 ifi->ifi_ra_timer = NULL;
683 } else if (!(oldifflags & IFF_UP) && /* DOWN to UP */
684 (ifi->ifi_flags & IFF_UP)) {
685 syslog(LOG_NOTICE,
686 "interface %s becomes up. restart timer.",
687 ifi->ifi_ifname);
688
689 ifi->ifi_state = IFI_STATE_TRANSITIVE;
690 ifi->ifi_burstcount =
691 MAX_INITIAL_RTR_ADVERTISEMENTS;
692 ifi->ifi_burstinterval =
693 MAX_INITIAL_RTR_ADVERT_INTERVAL;
694
695 ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout,
696 ra_timer_update, ifi, ifi);
697 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
698 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
699 ifi->ifi_ra_timer);
700 } else if (prefixchange &&
701 (ifi->ifi_flags & IFF_UP)) {
702 /*
703 * An advertised prefix has been added or invalidated.
704 * Will notice the change in a short delay.
705 */
706 set_short_delay(ifi);
707 }
708 }
709 }
710
711 void
rtadvd_input(struct sockinfo * s)712 rtadvd_input(struct sockinfo *s)
713 {
714 ssize_t i;
715 int *hlimp = NULL;
716 #ifdef OLDRAWSOCKET
717 struct ip6_hdr *ip;
718 #endif
719 struct icmp6_hdr *icp;
720 int ifindex = 0;
721 struct cmsghdr *cm;
722 struct in6_pktinfo *pi = NULL;
723 char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
724 struct in6_addr dst = in6addr_any;
725 struct ifinfo *ifi;
726
727 syslog(LOG_DEBUG, "<%s> enter", __func__);
728
729 if (s == NULL) {
730 syslog(LOG_ERR, "<%s> internal error", __func__);
731 exit(1);
732 }
733 /*
734 * Get message. We reset msg_controllen since the field could
735 * be modified if we had received a message before setting
736 * receive options.
737 */
738 rcvmhdr.msg_controllen = rcvcmsgbuflen;
739 if ((i = recvmsg(s->si_fd, &rcvmhdr, 0)) < 0)
740 return;
741
742 /* extract optional information via Advanced API */
743 for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr);
744 cm;
745 cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) {
746 if (cm->cmsg_level == IPPROTO_IPV6 &&
747 cm->cmsg_type == IPV6_PKTINFO &&
748 cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) {
749 pi = (struct in6_pktinfo *)(CMSG_DATA(cm));
750 ifindex = pi->ipi6_ifindex;
751 dst = pi->ipi6_addr;
752 }
753 if (cm->cmsg_level == IPPROTO_IPV6 &&
754 cm->cmsg_type == IPV6_HOPLIMIT &&
755 cm->cmsg_len == CMSG_LEN(sizeof(int)))
756 hlimp = (int *)CMSG_DATA(cm);
757 }
758 if (ifindex == 0) {
759 syslog(LOG_ERR, "failed to get receiving interface");
760 return;
761 }
762 if (hlimp == NULL) {
763 syslog(LOG_ERR, "failed to get receiving hop limit");
764 return;
765 }
766
767 /*
768 * If we happen to receive data on an interface which is now gone
769 * or down, just discard the data.
770 */
771 ifi = if_indextoifinfo(pi->ipi6_ifindex);
772 if (ifi == NULL || !(ifi->ifi_flags & IFF_UP)) {
773 syslog(LOG_INFO,
774 "<%s> received data on a disabled interface (%s)",
775 __func__,
776 (ifi == NULL) ? "[gone]" : ifi->ifi_ifname);
777 return;
778 }
779
780 #ifdef OLDRAWSOCKET
781 if ((size_t)i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) {
782 syslog(LOG_ERR,
783 "packet size(%d) is too short", i);
784 return;
785 }
786
787 ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base;
788 icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */
789 #else
790 if ((size_t)i < sizeof(struct icmp6_hdr)) {
791 syslog(LOG_ERR, "packet size(%zd) is too short", i);
792 return;
793 }
794
795 icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base;
796 #endif
797
798 switch (icp->icmp6_type) {
799 case ND_ROUTER_SOLICIT:
800 /*
801 * Message verification - RFC 4861 6.1.1
802 * XXX: these checks must be done in the kernel as well,
803 * but we can't completely rely on them.
804 */
805 if (*hlimp != 255) {
806 syslog(LOG_NOTICE,
807 "RS with invalid hop limit(%d) "
808 "received from %s on %s",
809 *hlimp,
810 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
811 sizeof(ntopbuf)),
812 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
813 return;
814 }
815 if (icp->icmp6_code) {
816 syslog(LOG_NOTICE,
817 "RS with invalid ICMP6 code(%d) "
818 "received from %s on %s",
819 icp->icmp6_code,
820 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
821 sizeof(ntopbuf)),
822 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
823 return;
824 }
825 if ((size_t)i < sizeof(struct nd_router_solicit)) {
826 syslog(LOG_NOTICE,
827 "RS from %s on %s does not have enough "
828 "length (len = %zd)",
829 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
830 sizeof(ntopbuf)),
831 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
832 return;
833 }
834 rs_input(i, (struct nd_router_solicit *)icp, pi, &rcvfrom);
835 break;
836 case ND_ROUTER_ADVERT:
837 /*
838 * Message verification - RFC 4861 6.1.2
839 * XXX: there's the same dilemma as above...
840 */
841 if (!IN6_IS_ADDR_LINKLOCAL(&rcvfrom.sin6_addr)) {
842 syslog(LOG_NOTICE,
843 "RA with non-linklocal source address "
844 "received from %s on %s",
845 inet_ntop(AF_INET6, &rcvfrom.sin6_addr,
846 ntopbuf, sizeof(ntopbuf)),
847 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
848 return;
849 }
850 if (*hlimp != 255) {
851 syslog(LOG_NOTICE,
852 "RA with invalid hop limit(%d) "
853 "received from %s on %s",
854 *hlimp,
855 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
856 sizeof(ntopbuf)),
857 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
858 return;
859 }
860 if (icp->icmp6_code) {
861 syslog(LOG_NOTICE,
862 "RA with invalid ICMP6 code(%d) "
863 "received from %s on %s",
864 icp->icmp6_code,
865 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
866 sizeof(ntopbuf)),
867 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
868 return;
869 }
870 if ((size_t)i < sizeof(struct nd_router_advert)) {
871 syslog(LOG_NOTICE,
872 "RA from %s on %s does not have enough "
873 "length (len = %zd)",
874 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf,
875 sizeof(ntopbuf)),
876 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
877 return;
878 }
879 ra_input(i, (struct nd_router_advert *)icp, pi, &rcvfrom);
880 break;
881 case ICMP6_ROUTER_RENUMBERING:
882 if (mcastif == NULL) {
883 syslog(LOG_ERR, "received a router renumbering "
884 "message, but not allowed to be accepted");
885 break;
886 }
887 rr_input(i, (struct icmp6_router_renum *)icp, pi, &rcvfrom,
888 &dst);
889 break;
890 default:
891 /*
892 * Note that this case is POSSIBLE, especially just
893 * after invocation of the daemon. This is because we
894 * could receive message after opening the socket and
895 * before setting ICMP6 type filter(see sock_open()).
896 */
897 syslog(LOG_ERR, "invalid icmp type(%d)", icp->icmp6_type);
898 return;
899 }
900 }
901
902 static void
rs_input(int len,struct nd_router_solicit * rs,struct in6_pktinfo * pi,struct sockaddr_in6 * from)903 rs_input(int len, struct nd_router_solicit *rs,
904 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
905 {
906 char ntopbuf[INET6_ADDRSTRLEN];
907 char ifnamebuf[IFNAMSIZ];
908 union nd_opt ndopts;
909 struct rainfo *rai;
910 struct ifinfo *ifi;
911 struct soliciter *sol;
912
913 syslog(LOG_DEBUG,
914 "<%s> RS received from %s on %s",
915 __func__,
916 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)),
917 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
918
919 /* ND option check */
920 memset(&ndopts, 0, sizeof(ndopts));
921 TAILQ_INIT(&ndopts.opt_list);
922 if (nd6_options((struct nd_opt_hdr *)(rs + 1),
923 len - sizeof(struct nd_router_solicit),
924 &ndopts, NDOPT_FLAG_SRCLINKADDR)) {
925 syslog(LOG_INFO,
926 "<%s> ND option check failed for an RS from %s on %s",
927 __func__,
928 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
929 sizeof(ntopbuf)),
930 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
931 return;
932 }
933
934 /*
935 * If the IP source address is the unspecified address, there
936 * must be no source link-layer address option in the message.
937 * (RFC 4861 6.1.1)
938 */
939 if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) &&
940 ndopts.opt_src_lladdr) {
941 syslog(LOG_INFO,
942 "<%s> RS from unspecified src on %s has a link-layer"
943 " address option",
944 __func__, if_indextoname(pi->ipi6_ifindex, ifnamebuf));
945 goto done;
946 }
947
948 ifi = if_indextoifinfo(pi->ipi6_ifindex);
949 if (ifi == NULL) {
950 syslog(LOG_INFO,
951 "<%s> if (idx=%d) not found. Why?",
952 __func__, pi->ipi6_ifindex);
953 goto done;
954 }
955 rai = ifi->ifi_rainfo;
956 if (rai == NULL) {
957 syslog(LOG_INFO,
958 "<%s> RS received on non advertising interface(%s)",
959 __func__,
960 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
961 goto done;
962 }
963
964 rai->rai_ifinfo->ifi_rsinput++;
965
966 /*
967 * Decide whether to send RA according to the rate-limit
968 * consideration.
969 */
970
971 /* record sockaddr waiting for RA, if possible */
972 sol = (struct soliciter *)malloc(sizeof(*sol));
973 if (sol) {
974 sol->sol_addr = *from;
975 /* XXX RFC 2553 need clarification on flowinfo */
976 sol->sol_addr.sin6_flowinfo = 0;
977 TAILQ_INSERT_TAIL(&rai->rai_soliciter, sol, sol_next);
978 }
979
980 /*
981 * If there is already a waiting RS packet, don't
982 * update the timer.
983 */
984 if (ifi->ifi_rs_waitcount++)
985 goto done;
986
987 set_short_delay(ifi);
988
989 done:
990 free_ndopts(&ndopts);
991 }
992
993 static void
set_short_delay(struct ifinfo * ifi)994 set_short_delay(struct ifinfo *ifi)
995 {
996 long delay; /* must not be greater than 1000000 */
997 struct timespec interval, now, min_delay, tm_tmp, *rest;
998
999 if (ifi->ifi_ra_timer == NULL)
1000 return;
1001 /*
1002 * Compute a random delay. If the computed value
1003 * corresponds to a time later than the time the next
1004 * multicast RA is scheduled to be sent, ignore the random
1005 * delay and send the advertisement at the
1006 * already-scheduled time. RFC 4861 6.2.6
1007 */
1008 delay = arc4random_uniform(MAX_RA_DELAY_TIME);
1009 interval.tv_sec = 0;
1010 interval.tv_nsec = delay * 1000;
1011 rest = rtadvd_timer_rest(ifi->ifi_ra_timer);
1012 if (TS_CMP(rest, &interval, <)) {
1013 syslog(LOG_DEBUG, "<%s> random delay is larger than "
1014 "the rest of the current timer", __func__);
1015 interval = *rest;
1016 }
1017
1018 /*
1019 * If we sent a multicast Router Advertisement within
1020 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule
1021 * the advertisement to be sent at a time corresponding to
1022 * MIN_DELAY_BETWEEN_RAS plus the random value after the
1023 * previous advertisement was sent.
1024 */
1025 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1026 TS_SUB(&now, &ifi->ifi_ra_lastsent, &tm_tmp);
1027 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS;
1028 min_delay.tv_nsec = 0;
1029 if (TS_CMP(&tm_tmp, &min_delay, <)) {
1030 TS_SUB(&min_delay, &tm_tmp, &min_delay);
1031 TS_ADD(&min_delay, &interval, &interval);
1032 }
1033 rtadvd_set_timer(&interval, ifi->ifi_ra_timer);
1034 }
1035
1036 static int
check_accept_rtadv(int idx)1037 check_accept_rtadv(int idx)
1038 {
1039 struct ifinfo *ifi;
1040
1041 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
1042 if (ifi->ifi_ifindex == idx)
1043 break;
1044 }
1045 if (ifi == NULL) {
1046 syslog(LOG_DEBUG,
1047 "<%s> if (idx=%d) not found. Why?",
1048 __func__, idx);
1049 return (0);
1050 }
1051
1052 /*
1053 * RA_RECV: ND6_IFF_ACCEPT_RTADV
1054 * RA_SEND: ip6.forwarding
1055 */
1056 if (update_ifinfo_nd_flags(ifi) != 0) {
1057 syslog(LOG_ERR, "cannot get nd6 flags (idx=%d)", idx);
1058 return (0);
1059 }
1060
1061 return (ifi->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV);
1062 }
1063
1064 static void
ra_input(int len,struct nd_router_advert * nra,struct in6_pktinfo * pi,struct sockaddr_in6 * from)1065 ra_input(int len, struct nd_router_advert *nra,
1066 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
1067 {
1068 struct rainfo *rai;
1069 struct ifinfo *ifi;
1070 char ntopbuf[INET6_ADDRSTRLEN];
1071 char ifnamebuf[IFNAMSIZ];
1072 union nd_opt ndopts;
1073 const char *on_off[] = {"OFF", "ON"};
1074 uint32_t reachabletime, retranstimer, mtu;
1075 int inconsistent = 0;
1076 int error;
1077
1078 syslog(LOG_DEBUG, "<%s> RA received from %s on %s", __func__,
1079 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)),
1080 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
1081
1082 /* ND option check */
1083 memset(&ndopts, 0, sizeof(ndopts));
1084 TAILQ_INIT(&ndopts.opt_list);
1085 error = nd6_options((struct nd_opt_hdr *)(nra + 1),
1086 len - sizeof(struct nd_router_advert), &ndopts,
1087 NDOPT_FLAG_SRCLINKADDR | NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU |
1088 NDOPT_FLAG_RDNSS | NDOPT_FLAG_DNSSL | NDOPT_FLAG_PREF64);
1089 if (error) {
1090 syslog(LOG_INFO,
1091 "<%s> ND option check failed for an RA from %s on %s",
1092 __func__,
1093 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1094 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex,
1095 ifnamebuf));
1096 return;
1097 }
1098
1099 /*
1100 * RA consistency check according to RFC 4861 6.2.7
1101 */
1102 ifi = if_indextoifinfo(pi->ipi6_ifindex);
1103 if (ifi->ifi_rainfo == NULL) {
1104 syslog(LOG_INFO,
1105 "<%s> received RA from %s on non-advertising"
1106 " interface(%s)",
1107 __func__,
1108 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1109 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex,
1110 ifnamebuf));
1111 goto done;
1112 }
1113 rai = ifi->ifi_rainfo;
1114 ifi->ifi_rainput++;
1115 syslog(LOG_DEBUG, "<%s> ifi->ifi_rainput = %" PRIu64, __func__,
1116 ifi->ifi_rainput);
1117
1118 /* Cur Hop Limit value */
1119 if (nra->nd_ra_curhoplimit && rai->rai_hoplimit &&
1120 nra->nd_ra_curhoplimit != rai->rai_hoplimit) {
1121 syslog(LOG_NOTICE,
1122 "CurHopLimit inconsistent on %s:"
1123 " %d from %s, %d from us",
1124 ifi->ifi_ifname, nra->nd_ra_curhoplimit,
1125 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1126 sizeof(ntopbuf)), rai->rai_hoplimit);
1127 inconsistent++;
1128 }
1129 /* M flag */
1130 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) !=
1131 rai->rai_managedflg) {
1132 syslog(LOG_NOTICE,
1133 "M flag inconsistent on %s:"
1134 " %s from %s, %s from us",
1135 ifi->ifi_ifname, on_off[!rai->rai_managedflg],
1136 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1137 sizeof(ntopbuf)), on_off[rai->rai_managedflg]);
1138 inconsistent++;
1139 }
1140 /* O flag */
1141 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) !=
1142 rai->rai_otherflg) {
1143 syslog(LOG_NOTICE,
1144 "O flag inconsistent on %s:"
1145 " %s from %s, %s from us",
1146 ifi->ifi_ifname, on_off[!rai->rai_otherflg],
1147 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1148 sizeof(ntopbuf)), on_off[rai->rai_otherflg]);
1149 inconsistent++;
1150 }
1151 #ifdef DRAFT_IETF_6MAN_IPV6ONLY_FLAG
1152 /* S "IPv6-Only" (Six, Silence-IPv4) flag */
1153 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_IPV6_ONLY) !=
1154 rai->rai_ipv6onlyflg) {
1155 syslog(LOG_NOTICE,
1156 "S flag inconsistent on %s:"
1157 " %s from %s, %s from us",
1158 ifi->ifi_ifname, on_off[!rai->rai_ipv6onlyflg],
1159 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1160 sizeof(ntopbuf)), on_off[rai->rai_ipv6onlyflg]);
1161 inconsistent++;
1162 }
1163 #endif
1164 /* Reachable Time */
1165 reachabletime = ntohl(nra->nd_ra_reachable);
1166 if (reachabletime && rai->rai_reachabletime &&
1167 reachabletime != rai->rai_reachabletime) {
1168 syslog(LOG_NOTICE,
1169 "ReachableTime inconsistent on %s:"
1170 " %d from %s, %d from us",
1171 ifi->ifi_ifname, reachabletime,
1172 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1173 sizeof(ntopbuf)), rai->rai_reachabletime);
1174 inconsistent++;
1175 }
1176 /* Retrans Timer */
1177 retranstimer = ntohl(nra->nd_ra_retransmit);
1178 if (retranstimer && rai->rai_retranstimer &&
1179 retranstimer != rai->rai_retranstimer) {
1180 syslog(LOG_NOTICE,
1181 "RetranceTimer inconsistent on %s:"
1182 " %d from %s, %d from us",
1183 ifi->ifi_ifname, retranstimer,
1184 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1185 sizeof(ntopbuf)), rai->rai_retranstimer);
1186 inconsistent++;
1187 }
1188 /* Values in the MTU options */
1189 if (ndopts.opt_mtu) {
1190 mtu = ntohl(ndopts.opt_mtu->nd_opt_mtu_mtu);
1191 if (mtu && rai->rai_linkmtu && mtu != rai->rai_linkmtu) {
1192 syslog(LOG_NOTICE,
1193 "MTU option value inconsistent on %s:"
1194 " %d from %s, %d from us",
1195 ifi->ifi_ifname, mtu,
1196 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1197 sizeof(ntopbuf)), rai->rai_linkmtu);
1198 inconsistent++;
1199 }
1200 }
1201 /* Preferred and Valid Lifetimes for prefixes */
1202 {
1203 struct nd_optlist *nol;
1204
1205 if (ndopts.opt_pi)
1206 if (prefix_check(ndopts.opt_pi, rai, from))
1207 inconsistent++;
1208
1209 TAILQ_FOREACH(nol, &ndopts.opt_list, nol_next)
1210 if (prefix_check((struct nd_opt_prefix_info *)nol->nol_opt,
1211 rai, from))
1212 inconsistent++;
1213 }
1214
1215 if (inconsistent)
1216 ifi->ifi_rainconsistent++;
1217
1218 done:
1219 free_ndopts(&ndopts);
1220 }
1221
1222 static uint32_t
udiff(uint32_t u,uint32_t v)1223 udiff(uint32_t u, uint32_t v)
1224 {
1225 return (u >= v ? u - v : v - u);
1226 }
1227
1228 /* return a non-zero value if the received prefix is inconsistent with ours */
1229 static int
prefix_check(struct nd_opt_prefix_info * pinfo,struct rainfo * rai,struct sockaddr_in6 * from)1230 prefix_check(struct nd_opt_prefix_info *pinfo,
1231 struct rainfo *rai, struct sockaddr_in6 *from)
1232 {
1233 struct ifinfo *ifi;
1234 uint32_t preferred_time, valid_time;
1235 struct prefix *pfx;
1236 int inconsistent = 0;
1237 char ntopbuf[INET6_ADDRSTRLEN];
1238 char prefixbuf[INET6_ADDRSTRLEN];
1239 struct timespec now;
1240
1241 #if 0 /* impossible */
1242 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION)
1243 return (0);
1244 #endif
1245 ifi = rai->rai_ifinfo;
1246 /*
1247 * log if the adveritsed prefix has link-local scope(sanity check?)
1248 */
1249 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix))
1250 syslog(LOG_INFO,
1251 "<%s> link-local prefix %s/%d is advertised "
1252 "from %s on %s",
1253 __func__,
1254 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1255 sizeof(prefixbuf)),
1256 pinfo->nd_opt_pi_prefix_len,
1257 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1258 sizeof(ntopbuf)), ifi->ifi_ifname);
1259
1260 if ((pfx = find_prefix(rai, &pinfo->nd_opt_pi_prefix,
1261 pinfo->nd_opt_pi_prefix_len)) == NULL) {
1262 syslog(LOG_INFO,
1263 "<%s> prefix %s/%d from %s on %s is not in our list",
1264 __func__,
1265 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1266 sizeof(prefixbuf)),
1267 pinfo->nd_opt_pi_prefix_len,
1268 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1269 sizeof(ntopbuf)), ifi->ifi_ifname);
1270 return (0);
1271 }
1272
1273 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time);
1274 if (pfx->pfx_pltimeexpire) {
1275 /*
1276 * The lifetime is decremented in real time, so we should
1277 * compare the expiration time.
1278 * (RFC 2461 Section 6.2.7.)
1279 * XXX: can we really expect that all routers on the link
1280 * have synchronized clocks?
1281 */
1282 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1283 preferred_time += now.tv_sec;
1284
1285 if (!pfx->pfx_timer && rai->rai_clockskew &&
1286 udiff(preferred_time, pfx->pfx_pltimeexpire) > rai->rai_clockskew) {
1287 syslog(LOG_INFO,
1288 "<%s> preferred lifetime for %s/%d"
1289 " (decr. in real time) inconsistent on %s:"
1290 " %" PRIu32 " from %s, %" PRIu32 " from us",
1291 __func__,
1292 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1293 sizeof(prefixbuf)),
1294 pinfo->nd_opt_pi_prefix_len,
1295 ifi->ifi_ifname, preferred_time,
1296 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1297 sizeof(ntopbuf)), pfx->pfx_pltimeexpire);
1298 inconsistent++;
1299 }
1300 } else if (!pfx->pfx_timer && preferred_time != pfx->pfx_preflifetime)
1301 syslog(LOG_INFO,
1302 "<%s> preferred lifetime for %s/%d"
1303 " inconsistent on %s:"
1304 " %d from %s, %d from us",
1305 __func__,
1306 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1307 sizeof(prefixbuf)),
1308 pinfo->nd_opt_pi_prefix_len,
1309 ifi->ifi_ifname, preferred_time,
1310 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1311 sizeof(ntopbuf)), pfx->pfx_preflifetime);
1312
1313 valid_time = ntohl(pinfo->nd_opt_pi_valid_time);
1314 if (pfx->pfx_vltimeexpire) {
1315 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1316 valid_time += now.tv_sec;
1317
1318 if (!pfx->pfx_timer && rai->rai_clockskew &&
1319 udiff(valid_time, pfx->pfx_vltimeexpire) > rai->rai_clockskew) {
1320 syslog(LOG_INFO,
1321 "<%s> valid lifetime for %s/%d"
1322 " (decr. in real time) inconsistent on %s:"
1323 " %d from %s, %" PRIu32 " from us",
1324 __func__,
1325 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1326 sizeof(prefixbuf)),
1327 pinfo->nd_opt_pi_prefix_len,
1328 ifi->ifi_ifname, preferred_time,
1329 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1330 sizeof(ntopbuf)), pfx->pfx_vltimeexpire);
1331 inconsistent++;
1332 }
1333 } else if (!pfx->pfx_timer && valid_time != pfx->pfx_validlifetime) {
1334 syslog(LOG_INFO,
1335 "<%s> valid lifetime for %s/%d"
1336 " inconsistent on %s:"
1337 " %d from %s, %d from us",
1338 __func__,
1339 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1340 sizeof(prefixbuf)),
1341 pinfo->nd_opt_pi_prefix_len,
1342 ifi->ifi_ifname, valid_time,
1343 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1344 sizeof(ntopbuf)), pfx->pfx_validlifetime);
1345 inconsistent++;
1346 }
1347
1348 return (inconsistent);
1349 }
1350
1351 struct prefix *
find_prefix(struct rainfo * rai,struct in6_addr * prefix,int plen)1352 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen)
1353 {
1354 struct prefix *pfx;
1355 int bytelen, bitlen;
1356 char bitmask;
1357
1358 TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) {
1359 if (plen != pfx->pfx_prefixlen)
1360 continue;
1361
1362 bytelen = plen / 8;
1363 bitlen = plen % 8;
1364 bitmask = 0xff << (8 - bitlen);
1365
1366 if (memcmp((void *)prefix, (void *)&pfx->pfx_prefix, bytelen))
1367 continue;
1368
1369 if (bitlen == 0 ||
1370 ((prefix->s6_addr[bytelen] & bitmask) ==
1371 (pfx->pfx_prefix.s6_addr[bytelen] & bitmask))) {
1372 return (pfx);
1373 }
1374 }
1375
1376 return (NULL);
1377 }
1378
1379 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */
1380 int
prefix_match(struct in6_addr * p0,int plen0,struct in6_addr * p1,int plen1)1381 prefix_match(struct in6_addr *p0, int plen0,
1382 struct in6_addr *p1, int plen1)
1383 {
1384 int bytelen, bitlen;
1385 char bitmask;
1386
1387 if (plen0 < plen1)
1388 return (0);
1389
1390 bytelen = plen1 / 8;
1391 bitlen = plen1 % 8;
1392 bitmask = 0xff << (8 - bitlen);
1393
1394 if (memcmp((void *)p0, (void *)p1, bytelen))
1395 return (0);
1396
1397 if (bitlen == 0 ||
1398 ((p0->s6_addr[bytelen] & bitmask) ==
1399 (p1->s6_addr[bytelen] & bitmask))) {
1400 return (1);
1401 }
1402
1403 return (0);
1404 }
1405
1406 static int
nd6_options(struct nd_opt_hdr * hdr,int limit,union nd_opt * ndopts,uint32_t optflags)1407 nd6_options(struct nd_opt_hdr *hdr, int limit,
1408 union nd_opt *ndopts, uint32_t optflags)
1409 {
1410 int optlen = 0;
1411
1412 for (; limit > 0; limit -= optlen) {
1413 if ((size_t)limit < sizeof(struct nd_opt_hdr)) {
1414 syslog(LOG_INFO, "<%s> short option header", __func__);
1415 goto bad;
1416 }
1417
1418 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen);
1419 if (hdr->nd_opt_len == 0) {
1420 syslog(LOG_INFO,
1421 "<%s> bad ND option length(0) (type = %d)",
1422 __func__, hdr->nd_opt_type);
1423 goto bad;
1424 }
1425 optlen = hdr->nd_opt_len << 3;
1426 if (optlen > limit) {
1427 syslog(LOG_INFO, "<%s> short option", __func__);
1428 goto bad;
1429 }
1430
1431 if (hdr->nd_opt_type > ND_OPT_MTU &&
1432 hdr->nd_opt_type != ND_OPT_RDNSS &&
1433 hdr->nd_opt_type != ND_OPT_DNSSL &&
1434 hdr->nd_opt_type != ND_OPT_PREF64) {
1435 syslog(LOG_INFO, "<%s> unknown ND option(type %d)",
1436 __func__, hdr->nd_opt_type);
1437 continue;
1438 }
1439
1440 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) {
1441 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)",
1442 __func__, hdr->nd_opt_type);
1443 continue;
1444 }
1445
1446 /*
1447 * Option length check. Do it here for all fixed-length
1448 * options.
1449 */
1450 switch (hdr->nd_opt_type) {
1451 case ND_OPT_MTU:
1452 if (optlen == sizeof(struct nd_opt_mtu))
1453 break;
1454 goto skip;
1455 case ND_OPT_RDNSS:
1456 if (optlen >= 24 &&
1457 (optlen - sizeof(struct nd_opt_rdnss)) % 16 == 0)
1458 break;
1459 goto skip;
1460 case ND_OPT_DNSSL:
1461 if (optlen >= 16 &&
1462 (optlen - sizeof(struct nd_opt_dnssl)) % 8 == 0)
1463 break;
1464 goto skip;
1465 case ND_OPT_PREFIX_INFORMATION:
1466 if (optlen == sizeof(struct nd_opt_prefix_info))
1467 break;
1468 skip:
1469 syslog(LOG_INFO, "<%s> invalid option length",
1470 __func__);
1471 continue;
1472 }
1473
1474 switch (hdr->nd_opt_type) {
1475 case ND_OPT_TARGET_LINKADDR:
1476 case ND_OPT_REDIRECTED_HEADER:
1477 case ND_OPT_RDNSS:
1478 case ND_OPT_DNSSL:
1479 case ND_OPT_PREF64:
1480 break; /* we don't care about these options */
1481 case ND_OPT_SOURCE_LINKADDR:
1482 case ND_OPT_MTU:
1483 if (ndopts->opt_array[hdr->nd_opt_type]) {
1484 syslog(LOG_INFO,
1485 "<%s> duplicated ND option (type = %d)",
1486 __func__, hdr->nd_opt_type);
1487 }
1488 ndopts->opt_array[hdr->nd_opt_type] = hdr;
1489 break;
1490 case ND_OPT_PREFIX_INFORMATION:
1491 {
1492 struct nd_optlist *nol;
1493
1494 if (ndopts->opt_pi == 0) {
1495 ndopts->opt_pi =
1496 (struct nd_opt_prefix_info *)hdr;
1497 continue;
1498 }
1499 nol = malloc(sizeof(*nol));
1500 if (nol == NULL) {
1501 syslog(LOG_ERR, "<%s> can't allocate memory",
1502 __func__);
1503 goto bad;
1504 }
1505 nol->nol_opt = hdr;
1506 TAILQ_INSERT_TAIL(&(ndopts->opt_list), nol, nol_next);
1507
1508 break;
1509 }
1510 default: /* impossible */
1511 break;
1512 }
1513 }
1514
1515 return (0);
1516
1517 bad:
1518 free_ndopts(ndopts);
1519
1520 return (-1);
1521 }
1522
1523 static void
free_ndopts(union nd_opt * ndopts)1524 free_ndopts(union nd_opt *ndopts)
1525 {
1526 struct nd_optlist *nol;
1527
1528 while ((nol = TAILQ_FIRST(&ndopts->opt_list)) != NULL) {
1529 TAILQ_REMOVE(&ndopts->opt_list, nol, nol_next);
1530 free(nol);
1531 }
1532 }
1533
1534 void
sock_open(struct sockinfo * s)1535 sock_open(struct sockinfo *s)
1536 {
1537 struct icmp6_filter filt;
1538 int on;
1539 /* XXX: should be max MTU attached to the node */
1540 static char answer[1500];
1541
1542 syslog(LOG_DEBUG, "<%s> enter", __func__);
1543
1544 if (s == NULL) {
1545 syslog(LOG_ERR, "<%s> internal error", __func__);
1546 exit(1);
1547 }
1548 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1549 CMSG_SPACE(sizeof(int));
1550 rcvcmsgbuf = (char *)malloc(rcvcmsgbuflen);
1551 if (rcvcmsgbuf == NULL) {
1552 syslog(LOG_ERR, "<%s> not enough core", __func__);
1553 exit(1);
1554 }
1555
1556 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1557 CMSG_SPACE(sizeof(int));
1558 sndcmsgbuf = (char *)malloc(sndcmsgbuflen);
1559 if (sndcmsgbuf == NULL) {
1560 syslog(LOG_ERR, "<%s> not enough core", __func__);
1561 exit(1);
1562 }
1563
1564 if ((s->si_fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
1565 syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno));
1566 exit(1);
1567 }
1568 /* specify to tell receiving interface */
1569 on = 1;
1570 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
1571 sizeof(on)) < 0) {
1572 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", __func__,
1573 strerror(errno));
1574 exit(1);
1575 }
1576 on = 1;
1577 /* specify to tell value of hoplimit field of received IP6 hdr */
1578 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
1579 sizeof(on)) < 0) {
1580 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", __func__,
1581 strerror(errno));
1582 exit(1);
1583 }
1584 ICMP6_FILTER_SETBLOCKALL(&filt);
1585 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt);
1586 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
1587 if (mcastif != NULL)
1588 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt);
1589
1590 if (setsockopt(s->si_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
1591 sizeof(filt)) < 0) {
1592 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s",
1593 __func__, strerror(errno));
1594 exit(1);
1595 }
1596
1597 /* initialize msghdr for receiving packets */
1598 rcviov[0].iov_base = (caddr_t)answer;
1599 rcviov[0].iov_len = sizeof(answer);
1600 rcvmhdr.msg_name = (caddr_t)&rcvfrom;
1601 rcvmhdr.msg_namelen = sizeof(rcvfrom);
1602 rcvmhdr.msg_iov = rcviov;
1603 rcvmhdr.msg_iovlen = 1;
1604 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
1605 rcvmhdr.msg_controllen = rcvcmsgbuflen;
1606
1607 /* initialize msghdr for sending packets */
1608 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
1609 sndmhdr.msg_iov = sndiov;
1610 sndmhdr.msg_iovlen = 1;
1611 sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
1612 sndmhdr.msg_controllen = sndcmsgbuflen;
1613 }
1614
1615 /* open a routing socket to watch the routing table */
1616 static void
rtsock_open(struct sockinfo * s)1617 rtsock_open(struct sockinfo *s)
1618 {
1619 if (s == NULL) {
1620 syslog(LOG_ERR, "<%s> internal error", __func__);
1621 exit(1);
1622 }
1623 if ((s->si_fd = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) {
1624 syslog(LOG_ERR,
1625 "<%s> socket: %s", __func__, strerror(errno));
1626 exit(1);
1627 }
1628 }
1629
1630 struct ifinfo *
if_indextoifinfo(int idx)1631 if_indextoifinfo(int idx)
1632 {
1633 struct ifinfo *ifi;
1634 char *name, name0[IFNAMSIZ];
1635
1636 /* Check if the interface has a valid name or not. */
1637 if (if_indextoname(idx, name0) == NULL)
1638 return (NULL);
1639
1640 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
1641 if (ifi->ifi_ifindex == idx)
1642 return (ifi);
1643 }
1644
1645 if (ifi != NULL)
1646 syslog(LOG_DEBUG, "<%s> ifi found (idx=%d)",
1647 __func__, idx);
1648 else
1649 syslog(LOG_DEBUG, "<%s> ifi not found (idx=%d)",
1650 __func__, idx);
1651
1652 return (NULL); /* search failed */
1653 }
1654
1655 void
ra_output(struct ifinfo * ifi)1656 ra_output(struct ifinfo *ifi)
1657 {
1658 int i;
1659 struct cmsghdr *cm;
1660 struct in6_pktinfo *pi;
1661 struct soliciter *sol;
1662 struct rainfo *rai;
1663
1664 switch (ifi->ifi_state) {
1665 case IFI_STATE_CONFIGURED:
1666 rai = ifi->ifi_rainfo;
1667 break;
1668 case IFI_STATE_TRANSITIVE:
1669 rai = ifi->ifi_rainfo_trans;
1670 break;
1671 case IFI_STATE_UNCONFIGURED:
1672 syslog(LOG_DEBUG, "<%s> %s is unconfigured. "
1673 "Skip sending RAs.",
1674 __func__, ifi->ifi_ifname);
1675 return;
1676 default:
1677 rai = NULL;
1678 }
1679 if (rai == NULL) {
1680 syslog(LOG_DEBUG, "<%s> rainfo is NULL on %s."
1681 "Skip sending RAs.",
1682 __func__, ifi->ifi_ifname);
1683 return;
1684 }
1685 if (!(ifi->ifi_flags & IFF_UP)) {
1686 syslog(LOG_DEBUG, "<%s> %s is not up. "
1687 "Skip sending RAs.",
1688 __func__, ifi->ifi_ifname);
1689 return;
1690 }
1691 /*
1692 * Check lifetime, ACCEPT_RTADV flag, and ip6.forwarding.
1693 *
1694 * (lifetime == 0) = output
1695 * (lifetime != 0 && (check_accept_rtadv()) = no output
1696 *
1697 * Basically, hosts MUST NOT send Router Advertisement
1698 * messages at any time (RFC 4861, Section 6.2.3). However, it
1699 * would sometimes be useful to allow hosts to advertise some
1700 * parameters such as prefix information and link MTU. Thus,
1701 * we allow hosts to invoke rtadvd only when router lifetime
1702 * (on every advertising interface) is explicitly set
1703 * zero. (see also the above section)
1704 */
1705 syslog(LOG_DEBUG,
1706 "<%s> check lifetime=%d, ACCEPT_RTADV=%d, ip6.forwarding=%d "
1707 "on %s", __func__,
1708 rai->rai_lifetime,
1709 check_accept_rtadv(ifi->ifi_ifindex),
1710 getinet6sysctl(IPV6CTL_FORWARDING),
1711 ifi->ifi_ifname);
1712
1713 if (rai->rai_lifetime != 0) {
1714 if (getinet6sysctl(IPV6CTL_FORWARDING) == 0) {
1715 syslog(LOG_ERR,
1716 "non-zero lifetime RA "
1717 "but net.inet6.ip6.forwarding=0. "
1718 "Ignored.");
1719 return;
1720 }
1721 if (check_accept_rtadv(ifi->ifi_ifindex)) {
1722 syslog(LOG_ERR,
1723 "non-zero lifetime RA "
1724 "on RA receiving interface %s."
1725 " Ignored.", ifi->ifi_ifname);
1726 return;
1727 }
1728 }
1729
1730 make_packet(rai); /* XXX: inefficient */
1731
1732 sndmhdr.msg_name = (caddr_t)&sin6_linklocal_allnodes;
1733 sndmhdr.msg_iov[0].iov_base = (caddr_t)rai->rai_ra_data;
1734 sndmhdr.msg_iov[0].iov_len = rai->rai_ra_datalen;
1735
1736 cm = CMSG_FIRSTHDR(&sndmhdr);
1737 /* specify the outgoing interface */
1738 cm->cmsg_level = IPPROTO_IPV6;
1739 cm->cmsg_type = IPV6_PKTINFO;
1740 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
1741 pi = (struct in6_pktinfo *)CMSG_DATA(cm);
1742 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/
1743 pi->ipi6_ifindex = ifi->ifi_ifindex;
1744
1745 /* specify the hop limit of the packet */
1746 {
1747 int hoplimit = 255;
1748
1749 cm = CMSG_NXTHDR(&sndmhdr, cm);
1750 cm->cmsg_level = IPPROTO_IPV6;
1751 cm->cmsg_type = IPV6_HOPLIMIT;
1752 cm->cmsg_len = CMSG_LEN(sizeof(int));
1753 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
1754 }
1755
1756 syslog(LOG_DEBUG,
1757 "<%s> send RA on %s, # of RS waitings = %d",
1758 __func__, ifi->ifi_ifname, ifi->ifi_rs_waitcount);
1759
1760 i = sendmsg(sock.si_fd, &sndmhdr, 0);
1761
1762 if (i < 0 || (size_t)i != rai->rai_ra_datalen) {
1763 if (i < 0) {
1764 syslog(LOG_ERR, "<%s> sendmsg on %s: %s",
1765 __func__, ifi->ifi_ifname,
1766 strerror(errno));
1767 }
1768 }
1769
1770 /*
1771 * unicast advertisements
1772 * XXX commented out. reason: though spec does not forbit it, unicast
1773 * advert does not really help
1774 */
1775 while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) {
1776 TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next);
1777 free(sol);
1778 }
1779
1780 /* update timestamp */
1781 clock_gettime(CLOCK_MONOTONIC_FAST, &ifi->ifi_ra_lastsent);
1782
1783 /* update counter */
1784 ifi->ifi_rs_waitcount = 0;
1785 ifi->ifi_raoutput++;
1786
1787 switch (ifi->ifi_state) {
1788 case IFI_STATE_CONFIGURED:
1789 if (ifi->ifi_burstcount > 0)
1790 ifi->ifi_burstcount--;
1791 break;
1792 case IFI_STATE_TRANSITIVE:
1793 ifi->ifi_burstcount--;
1794 if (ifi->ifi_burstcount == 0) {
1795 if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) {
1796 /* Initial burst finished. */
1797 if (ifi->ifi_rainfo_trans != NULL)
1798 ifi->ifi_rainfo_trans = NULL;
1799 }
1800
1801 /* Remove burst RA information */
1802 if (ifi->ifi_rainfo_trans != NULL) {
1803 rm_rainfo(ifi->ifi_rainfo_trans);
1804 ifi->ifi_rainfo_trans = NULL;
1805 }
1806
1807 if (ifi->ifi_rainfo != NULL) {
1808 /*
1809 * TRANSITIVE -> CONFIGURED
1810 *
1811 * After initial burst or transition from
1812 * one configuration to another,
1813 * ifi_rainfo always points to the next RA
1814 * information.
1815 */
1816 ifi->ifi_state = IFI_STATE_CONFIGURED;
1817 syslog(LOG_DEBUG,
1818 "<%s> ifname=%s marked as "
1819 "CONFIGURED.", __func__,
1820 ifi->ifi_ifname);
1821 } else {
1822 /*
1823 * TRANSITIVE -> UNCONFIGURED
1824 *
1825 * If ifi_rainfo points to NULL, this
1826 * interface is shutting down.
1827 *
1828 */
1829 int error;
1830
1831 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
1832 syslog(LOG_DEBUG,
1833 "<%s> ifname=%s marked as "
1834 "UNCONFIGURED.", __func__,
1835 ifi->ifi_ifname);
1836 error = sock_mc_leave(&sock,
1837 ifi->ifi_ifindex);
1838 if (error)
1839 exit(1);
1840 }
1841 }
1842 break;
1843 }
1844 }
1845
1846 /* process RA timer */
1847 struct rtadvd_timer *
ra_timeout(void * arg)1848 ra_timeout(void *arg)
1849 {
1850 struct ifinfo *ifi;
1851
1852 ifi = (struct ifinfo *)arg;
1853 syslog(LOG_DEBUG, "<%s> RA timer on %s is expired",
1854 __func__, ifi->ifi_ifname);
1855
1856 ra_output(ifi);
1857
1858 return (ifi->ifi_ra_timer);
1859 }
1860
1861 /* update RA timer */
1862 void
ra_timer_update(void * arg,struct timespec * tm)1863 ra_timer_update(void *arg, struct timespec *tm)
1864 {
1865 uint16_t interval;
1866 struct rainfo *rai;
1867 struct ifinfo *ifi;
1868
1869 ifi = (struct ifinfo *)arg;
1870 rai = ifi->ifi_rainfo;
1871 interval = 0;
1872
1873 switch (ifi->ifi_state) {
1874 case IFI_STATE_UNCONFIGURED:
1875 return;
1876 break;
1877 case IFI_STATE_CONFIGURED:
1878 /*
1879 * Whenever a multicast advertisement is sent from
1880 * an interface, the timer is reset to a
1881 * uniformly-distributed random value between the
1882 * interface's configured MinRtrAdvInterval and
1883 * MaxRtrAdvInterval (RFC4861 6.2.4).
1884 */
1885 interval = rai->rai_mininterval;
1886 interval += arc4random_uniform(rai->rai_maxinterval -
1887 rai->rai_mininterval);
1888 break;
1889 case IFI_STATE_TRANSITIVE:
1890 /*
1891 * For the first few advertisements (up to
1892 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen
1893 * interval is greater than
1894 * MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer SHOULD be
1895 * set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. (RFC
1896 * 4861 6.2.4)
1897 *
1898 * In such cases, the router SHOULD transmit one or more
1899 * (but not more than MAX_FINAL_RTR_ADVERTISEMENTS) final
1900 * multicast Router Advertisements on the interface with a
1901 * Router Lifetime field of zero. (RFC 4861 6.2.5)
1902 */
1903 interval = ifi->ifi_burstinterval;
1904 break;
1905 }
1906
1907 tm->tv_sec = interval;
1908 tm->tv_nsec = 0;
1909
1910 syslog(LOG_DEBUG,
1911 "<%s> RA timer on %s is set to %ld:%ld",
1912 __func__, ifi->ifi_ifname,
1913 (long int)tm->tv_sec, (long int)tm->tv_nsec / 1000);
1914 }
1915