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
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 pid, 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 pfh = pidfile_open(pidfilename, 0600, &otherpid);
246 if (pfh == NULL) {
247 if (errno == EEXIST)
248 errx(1, "%s already running, pid: %d",
249 getprogname(), otherpid);
250 syslog(LOG_ERR,
251 "failed to open the pid file %s, run anyway.",
252 pidfilename);
253 }
254 if (!fflag)
255 daemon(1, 0);
256
257 sock_open(&sock);
258
259 update_ifinfo(&ifilist, UPDATE_IFINFO_ALL);
260 for (i = 0; i < argc; i++)
261 update_persist_ifinfo(&ifilist, argv[i]);
262
263 csock_open(&ctrlsock, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
264 if (ctrlsock.si_fd == -1) {
265 syslog(LOG_ERR, "cannot open control socket: %s",
266 strerror(errno));
267 exit(1);
268 }
269
270 /* record the current PID */
271 pid = getpid();
272 pidfile_write(pfh);
273
274 set[PFD_RAWSOCK].fd = sock.si_fd;
275 set[PFD_RAWSOCK].events = POLLIN;
276 if (sflag == 0) {
277 rtsock_open(&rtsock);
278 set[PFD_RTSOCK].fd = rtsock.si_fd;
279 set[PFD_RTSOCK].events = POLLIN;
280 } else
281 set[PFD_RTSOCK].fd = -1;
282 set[PFD_CSOCK].fd = ctrlsock.si_fd;
283 set[PFD_CSOCK].events = POLLIN;
284 signal(SIGTERM, set_do_shutdown);
285 signal(SIGINT, set_do_shutdown);
286 signal(SIGHUP, set_do_reload);
287
288 error = csock_listen(&ctrlsock);
289 if (error) {
290 syslog(LOG_ERR, "cannot listen control socket: %s",
291 strerror(errno));
292 exit(1);
293 }
294
295 /* load configuration file */
296 set_do_reload(0);
297
298 while (1) {
299 if (is_do_shutdown())
300 rtadvd_shutdown();
301
302 if (is_do_reload()) {
303 loadconfig_ifname(reload_ifname());
304 if (reload_ifname() == NULL)
305 syslog(LOG_INFO,
306 "configuration file reloaded.");
307 else
308 syslog(LOG_INFO,
309 "configuration file for %s reloaded.",
310 reload_ifname());
311 reset_do_reload();
312 }
313
314 /* timeout handler update for active interfaces */
315 rtadvd_update_timeout_handler();
316
317 /* timer expiration check and reset the timer */
318 timeout = rtadvd_check_timer();
319
320 if (timeout != NULL) {
321 syslog(LOG_DEBUG,
322 "<%s> set timer to %ld:%ld. waiting for "
323 "inputs or timeout", __func__,
324 (long int)timeout->tv_sec,
325 (long int)timeout->tv_nsec / 1000);
326 } else {
327 syslog(LOG_DEBUG,
328 "<%s> there's no timer. waiting for inputs",
329 __func__);
330 }
331 if ((i = poll(set, sizeof(set)/sizeof(set[0]),
332 timeout ? (timeout->tv_sec * 1000 +
333 timeout->tv_nsec / 1000 / 1000) : INFTIM)) < 0) {
334
335 /* EINTR would occur if a signal was delivered */
336 if (errno != EINTR)
337 syslog(LOG_ERR, "poll() failed: %s",
338 strerror(errno));
339 continue;
340 }
341 if (i == 0) /* timeout */
342 continue;
343 if (rtsock.si_fd != -1 && set[PFD_RTSOCK].revents & POLLIN)
344 rtmsg_input(&rtsock);
345
346 if (set[PFD_RAWSOCK].revents & POLLIN)
347 rtadvd_input(&sock);
348
349 if (set[PFD_CSOCK].revents & POLLIN) {
350 int fd;
351
352 fd = csock_accept(&ctrlsock);
353 if (fd == -1)
354 syslog(LOG_ERR,
355 "cannot accept() control socket: %s",
356 strerror(errno));
357 else {
358 cm_handler_server(fd);
359 close(fd);
360 }
361 }
362 }
363 exit(0); /* NOTREACHED */
364 }
365
366 static void
rtadvd_shutdown(void)367 rtadvd_shutdown(void)
368 {
369 struct ifinfo *ifi;
370 struct rainfo *rai;
371 struct rdnss *rdn;
372 struct dnssl *dns;
373
374 if (wait_shutdown) {
375 syslog(LOG_INFO,
376 "waiting expiration of the all RA timers.");
377
378 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
379 /*
380 * Ignore !IFF_UP interfaces in waiting for shutdown.
381 */
382 if (!(ifi->ifi_flags & IFF_UP) &&
383 ifi->ifi_ra_timer != NULL) {
384 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
385 rtadvd_remove_timer(ifi->ifi_ra_timer);
386 ifi->ifi_ra_timer = NULL;
387 syslog(LOG_DEBUG, "<%s> %s(idx=%d) is down. "
388 "Timer removed and marked as UNCONFIGURED.",
389 __func__, ifi->ifi_ifname,
390 ifi->ifi_ifindex);
391 }
392 }
393 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
394 if (ifi->ifi_ra_timer != NULL)
395 break;
396 }
397 if (ifi == NULL) {
398 syslog(LOG_NOTICE, "gracefully terminated.");
399 exit(0);
400 }
401
402 sleep(1);
403 return;
404 }
405
406 syslog(LOG_DEBUG, "<%s> cease to be an advertising router",
407 __func__);
408
409 wait_shutdown = 1;
410
411 TAILQ_FOREACH(rai, &railist, rai_next) {
412 rai->rai_lifetime = 0;
413 TAILQ_FOREACH(rdn, &rai->rai_rdnss, rd_next)
414 rdn->rd_ltime = 0;
415 TAILQ_FOREACH(dns, &rai->rai_dnssl, dn_next)
416 dns->dn_ltime = 0;
417 }
418 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
419 if (!ifi->ifi_persist)
420 continue;
421 if (ifi->ifi_state == IFI_STATE_UNCONFIGURED)
422 continue;
423 if (ifi->ifi_ra_timer == NULL)
424 continue;
425 if (ifi->ifi_ra_lastsent.tv_sec == 0 &&
426 ifi->ifi_ra_lastsent.tv_nsec == 0 &&
427 ifi->ifi_ra_timer != NULL) {
428 /*
429 * When RA configured but never sent,
430 * ignore the IF immediately.
431 */
432 rtadvd_remove_timer(ifi->ifi_ra_timer);
433 ifi->ifi_ra_timer = NULL;
434 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
435 continue;
436 }
437
438 ifi->ifi_state = IFI_STATE_TRANSITIVE;
439
440 /* Mark as the shut-down state. */
441 ifi->ifi_rainfo_trans = ifi->ifi_rainfo;
442 ifi->ifi_rainfo = NULL;
443
444 ifi->ifi_burstcount = MAX_FINAL_RTR_ADVERTISEMENTS;
445 ifi->ifi_burstinterval = MIN_DELAY_BETWEEN_RAS;
446
447 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
448 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
449 ifi->ifi_ra_timer);
450 }
451 syslog(LOG_NOTICE, "final RA transmission started.");
452
453 pidfile_remove(pfh);
454 csock_close(&ctrlsock);
455 }
456
457 static void
rtmsg_input(struct sockinfo * s)458 rtmsg_input(struct sockinfo *s)
459 {
460 int n, type, ifindex = 0, plen;
461 size_t len;
462 char msg[2048], *next, *lim;
463 char ifname[IFNAMSIZ];
464 struct if_announcemsghdr *ifan;
465 struct rt_msghdr *rtm;
466 struct prefix *pfx;
467 struct rainfo *rai;
468 struct in6_addr *addr;
469 struct ifinfo *ifi;
470 char addrbuf[INET6_ADDRSTRLEN];
471 int prefixchange = 0;
472
473 if (s == NULL) {
474 syslog(LOG_ERR, "<%s> internal error", __func__);
475 exit(1);
476 }
477 n = read(s->si_fd, msg, sizeof(msg));
478 rtm = (struct rt_msghdr *)msg;
479 syslog(LOG_DEBUG, "<%s> received a routing message "
480 "(type = %d, len = %d)", __func__, rtm->rtm_type, n);
481
482 if (n > rtm->rtm_msglen) {
483 /*
484 * This usually won't happen for messages received on
485 * a routing socket.
486 */
487 syslog(LOG_DEBUG,
488 "<%s> received data length is larger than "
489 "1st routing message len. multiple messages? "
490 "read %d bytes, but 1st msg len = %d",
491 __func__, n, rtm->rtm_msglen);
492 #if 0
493 /* adjust length */
494 n = rtm->rtm_msglen;
495 #endif
496 }
497
498 lim = msg + n;
499 for (next = msg; next < lim; next += len) {
500 int oldifflags;
501
502 next = get_next_msg(next, lim, 0, &len,
503 RTADV_TYPE2BITMASK(RTM_ADD) |
504 RTADV_TYPE2BITMASK(RTM_DELETE) |
505 RTADV_TYPE2BITMASK(RTM_NEWADDR) |
506 RTADV_TYPE2BITMASK(RTM_DELADDR) |
507 RTADV_TYPE2BITMASK(RTM_IFINFO) |
508 RTADV_TYPE2BITMASK(RTM_IFANNOUNCE));
509 if (len == 0)
510 break;
511 type = ((struct rt_msghdr *)next)->rtm_type;
512 switch (type) {
513 case RTM_ADD:
514 case RTM_DELETE:
515 ifindex = get_rtm_ifindex(next);
516 break;
517 case RTM_NEWADDR:
518 case RTM_DELADDR:
519 ifindex = (int)((struct ifa_msghdr *)next)->ifam_index;
520 break;
521 case RTM_IFINFO:
522 ifindex = (int)((struct if_msghdr *)next)->ifm_index;
523 break;
524 case RTM_IFANNOUNCE:
525 ifan = (struct if_announcemsghdr *)next;
526 switch (ifan->ifan_what) {
527 case IFAN_ARRIVAL:
528 case IFAN_DEPARTURE:
529 break;
530 default:
531 syslog(LOG_DEBUG,
532 "<%s:%d> unknown ifan msg (ifan_what=%d)",
533 __func__, __LINE__, ifan->ifan_what);
534 continue;
535 }
536
537 syslog(LOG_DEBUG, "<%s>: if_announcemsg (idx=%d:%d)",
538 __func__, ifan->ifan_index, ifan->ifan_what);
539 switch (ifan->ifan_what) {
540 case IFAN_ARRIVAL:
541 syslog(LOG_NOTICE,
542 "interface added (idx=%d)",
543 ifan->ifan_index);
544 update_ifinfo(&ifilist, ifan->ifan_index);
545 loadconfig_index(ifan->ifan_index);
546 break;
547 case IFAN_DEPARTURE:
548 syslog(LOG_NOTICE,
549 "interface removed (idx=%d)",
550 ifan->ifan_index);
551 rm_ifinfo_index(ifan->ifan_index);
552
553 /* Clear ifi_ifindex */
554 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
555 if (ifi->ifi_ifindex
556 == ifan->ifan_index) {
557 ifi->ifi_ifindex = 0;
558 break;
559 }
560 }
561 update_ifinfo(&ifilist, ifan->ifan_index);
562 break;
563 }
564 continue;
565 default:
566 /* should not reach here */
567 syslog(LOG_DEBUG,
568 "<%s:%d> unknown rtmsg %d on %s",
569 __func__, __LINE__, type,
570 if_indextoname(ifindex, ifname));
571 continue;
572 }
573 ifi = if_indextoifinfo(ifindex);
574 if (ifi == NULL) {
575 syslog(LOG_DEBUG,
576 "<%s> ifinfo not found for idx=%d. Why?",
577 __func__, ifindex);
578 continue;
579 }
580 rai = ifi->ifi_rainfo;
581 if (rai == NULL) {
582 syslog(LOG_DEBUG,
583 "<%s> route changed on "
584 "non advertising interface(%s)",
585 __func__, ifi->ifi_ifname);
586 continue;
587 }
588
589 oldifflags = ifi->ifi_flags;
590 /* init ifflags because it may have changed */
591 update_ifinfo(&ifilist, ifindex);
592
593 switch (type) {
594 case RTM_ADD:
595 if (sflag)
596 break; /* we aren't interested in prefixes */
597
598 addr = get_addr(msg);
599 plen = get_prefixlen(msg);
600 /* sanity check for plen */
601 /* as RFC2373, prefixlen is at least 4 */
602 if (plen < 4 || plen > 127) {
603 syslog(LOG_INFO, "<%s> new interface route's"
604 "plen %d is invalid for a prefix",
605 __func__, plen);
606 break;
607 }
608 pfx = find_prefix(rai, addr, plen);
609 if (pfx) {
610 if (pfx->pfx_timer) {
611 /*
612 * If the prefix has been invalidated,
613 * make it available again.
614 */
615 update_prefix(pfx);
616 prefixchange = 1;
617 } else
618 syslog(LOG_DEBUG,
619 "<%s> new prefix(%s/%d) "
620 "added on %s, "
621 "but it was already in list",
622 __func__,
623 inet_ntop(AF_INET6, addr,
624 (char *)addrbuf,
625 sizeof(addrbuf)),
626 plen, ifi->ifi_ifname);
627 break;
628 }
629 make_prefix(rai, ifindex, addr, plen);
630 prefixchange = 1;
631 break;
632 case RTM_DELETE:
633 if (sflag)
634 break;
635
636 addr = get_addr(msg);
637 plen = get_prefixlen(msg);
638 /* sanity check for plen */
639 /* as RFC2373, prefixlen is at least 4 */
640 if (plen < 4 || plen > 127) {
641 syslog(LOG_INFO,
642 "<%s> deleted interface route's "
643 "plen %d is invalid for a prefix",
644 __func__, plen);
645 break;
646 }
647 pfx = find_prefix(rai, addr, plen);
648 if (pfx == NULL) {
649 syslog(LOG_DEBUG,
650 "<%s> prefix(%s/%d) was deleted on %s, "
651 "but it was not in list",
652 __func__, inet_ntop(AF_INET6, addr,
653 (char *)addrbuf, sizeof(addrbuf)),
654 plen, ifi->ifi_ifname);
655 break;
656 }
657 invalidate_prefix(pfx);
658 prefixchange = 1;
659 break;
660 case RTM_NEWADDR:
661 case RTM_DELADDR:
662 case RTM_IFINFO:
663 break;
664 default:
665 /* should not reach here */
666 syslog(LOG_DEBUG,
667 "<%s:%d> unknown rtmsg %d on %s",
668 __func__, __LINE__, type,
669 if_indextoname(ifindex, ifname));
670 return;
671 }
672
673 /* check if an interface flag is changed */
674 if ((oldifflags & IFF_UP) && /* UP to DOWN */
675 !(ifi->ifi_flags & IFF_UP)) {
676 syslog(LOG_NOTICE,
677 "<interface %s becomes down. stop timer.",
678 ifi->ifi_ifname);
679 rtadvd_remove_timer(ifi->ifi_ra_timer);
680 ifi->ifi_ra_timer = NULL;
681 } else if (!(oldifflags & IFF_UP) && /* DOWN to UP */
682 (ifi->ifi_flags & IFF_UP)) {
683 syslog(LOG_NOTICE,
684 "interface %s becomes up. restart timer.",
685 ifi->ifi_ifname);
686
687 ifi->ifi_state = IFI_STATE_TRANSITIVE;
688 ifi->ifi_burstcount =
689 MAX_INITIAL_RTR_ADVERTISEMENTS;
690 ifi->ifi_burstinterval =
691 MAX_INITIAL_RTR_ADVERT_INTERVAL;
692
693 ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout,
694 ra_timer_update, ifi, ifi);
695 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
696 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
697 ifi->ifi_ra_timer);
698 } else if (prefixchange &&
699 (ifi->ifi_flags & IFF_UP)) {
700 /*
701 * An advertised prefix has been added or invalidated.
702 * Will notice the change in a short delay.
703 */
704 set_short_delay(ifi);
705 }
706 }
707
708 return;
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 return;
902 }
903
904 static void
rs_input(int len,struct nd_router_solicit * rs,struct in6_pktinfo * pi,struct sockaddr_in6 * from)905 rs_input(int len, struct nd_router_solicit *rs,
906 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
907 {
908 char ntopbuf[INET6_ADDRSTRLEN];
909 char ifnamebuf[IFNAMSIZ];
910 union nd_opt ndopts;
911 struct rainfo *rai;
912 struct ifinfo *ifi;
913 struct soliciter *sol;
914
915 syslog(LOG_DEBUG,
916 "<%s> RS received from %s on %s",
917 __func__,
918 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)),
919 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
920
921 /* ND option check */
922 memset(&ndopts, 0, sizeof(ndopts));
923 TAILQ_INIT(&ndopts.opt_list);
924 if (nd6_options((struct nd_opt_hdr *)(rs + 1),
925 len - sizeof(struct nd_router_solicit),
926 &ndopts, NDOPT_FLAG_SRCLINKADDR)) {
927 syslog(LOG_INFO,
928 "<%s> ND option check failed for an RS from %s on %s",
929 __func__,
930 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
931 sizeof(ntopbuf)),
932 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
933 return;
934 }
935
936 /*
937 * If the IP source address is the unspecified address, there
938 * must be no source link-layer address option in the message.
939 * (RFC 4861 6.1.1)
940 */
941 if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) &&
942 ndopts.opt_src_lladdr) {
943 syslog(LOG_INFO,
944 "<%s> RS from unspecified src on %s has a link-layer"
945 " address option",
946 __func__, if_indextoname(pi->ipi6_ifindex, ifnamebuf));
947 goto done;
948 }
949
950 ifi = if_indextoifinfo(pi->ipi6_ifindex);
951 if (ifi == NULL) {
952 syslog(LOG_INFO,
953 "<%s> if (idx=%d) not found. Why?",
954 __func__, pi->ipi6_ifindex);
955 goto done;
956 }
957 rai = ifi->ifi_rainfo;
958 if (rai == NULL) {
959 syslog(LOG_INFO,
960 "<%s> RS received on non advertising interface(%s)",
961 __func__,
962 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
963 goto done;
964 }
965
966 rai->rai_ifinfo->ifi_rsinput++;
967
968 /*
969 * Decide whether to send RA according to the rate-limit
970 * consideration.
971 */
972
973 /* record sockaddr waiting for RA, if possible */
974 sol = (struct soliciter *)malloc(sizeof(*sol));
975 if (sol) {
976 sol->sol_addr = *from;
977 /* XXX RFC 2553 need clarification on flowinfo */
978 sol->sol_addr.sin6_flowinfo = 0;
979 TAILQ_INSERT_TAIL(&rai->rai_soliciter, sol, sol_next);
980 }
981
982 /*
983 * If there is already a waiting RS packet, don't
984 * update the timer.
985 */
986 if (ifi->ifi_rs_waitcount++)
987 goto done;
988
989 set_short_delay(ifi);
990
991 done:
992 free_ndopts(&ndopts);
993 return;
994 }
995
996 static void
set_short_delay(struct ifinfo * ifi)997 set_short_delay(struct ifinfo *ifi)
998 {
999 long delay; /* must not be greater than 1000000 */
1000 struct timespec interval, now, min_delay, tm_tmp, *rest;
1001
1002 if (ifi->ifi_ra_timer == NULL)
1003 return;
1004 /*
1005 * Compute a random delay. If the computed value
1006 * corresponds to a time later than the time the next
1007 * multicast RA is scheduled to be sent, ignore the random
1008 * delay and send the advertisement at the
1009 * already-scheduled time. RFC 4861 6.2.6
1010 */
1011 delay = arc4random_uniform(MAX_RA_DELAY_TIME);
1012 interval.tv_sec = 0;
1013 interval.tv_nsec = delay * 1000;
1014 rest = rtadvd_timer_rest(ifi->ifi_ra_timer);
1015 if (TS_CMP(rest, &interval, <)) {
1016 syslog(LOG_DEBUG, "<%s> random delay is larger than "
1017 "the rest of the current timer", __func__);
1018 interval = *rest;
1019 }
1020
1021 /*
1022 * If we sent a multicast Router Advertisement within
1023 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule
1024 * the advertisement to be sent at a time corresponding to
1025 * MIN_DELAY_BETWEEN_RAS plus the random value after the
1026 * previous advertisement was sent.
1027 */
1028 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1029 TS_SUB(&now, &ifi->ifi_ra_lastsent, &tm_tmp);
1030 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS;
1031 min_delay.tv_nsec = 0;
1032 if (TS_CMP(&tm_tmp, &min_delay, <)) {
1033 TS_SUB(&min_delay, &tm_tmp, &min_delay);
1034 TS_ADD(&min_delay, &interval, &interval);
1035 }
1036 rtadvd_set_timer(&interval, ifi->ifi_ra_timer);
1037 }
1038
1039 static int
check_accept_rtadv(int idx)1040 check_accept_rtadv(int idx)
1041 {
1042 struct ifinfo *ifi;
1043
1044 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
1045 if (ifi->ifi_ifindex == idx)
1046 break;
1047 }
1048 if (ifi == NULL) {
1049 syslog(LOG_DEBUG,
1050 "<%s> if (idx=%d) not found. Why?",
1051 __func__, idx);
1052 return (0);
1053 }
1054
1055 /*
1056 * RA_RECV: ND6_IFF_ACCEPT_RTADV
1057 * RA_SEND: ip6.forwarding
1058 */
1059 if (update_ifinfo_nd_flags(ifi) != 0) {
1060 syslog(LOG_ERR, "cannot get nd6 flags (idx=%d)", idx);
1061 return (0);
1062 }
1063
1064 return (ifi->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV);
1065 }
1066
1067 static void
ra_input(int len,struct nd_router_advert * nra,struct in6_pktinfo * pi,struct sockaddr_in6 * from)1068 ra_input(int len, struct nd_router_advert *nra,
1069 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
1070 {
1071 struct rainfo *rai;
1072 struct ifinfo *ifi;
1073 char ntopbuf[INET6_ADDRSTRLEN];
1074 char ifnamebuf[IFNAMSIZ];
1075 union nd_opt ndopts;
1076 const char *on_off[] = {"OFF", "ON"};
1077 uint32_t reachabletime, retranstimer, mtu;
1078 int inconsistent = 0;
1079 int error;
1080
1081 syslog(LOG_DEBUG, "<%s> RA received from %s on %s", __func__,
1082 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)),
1083 if_indextoname(pi->ipi6_ifindex, ifnamebuf));
1084
1085 /* ND option check */
1086 memset(&ndopts, 0, sizeof(ndopts));
1087 TAILQ_INIT(&ndopts.opt_list);
1088 error = nd6_options((struct nd_opt_hdr *)(nra + 1),
1089 len - sizeof(struct nd_router_advert), &ndopts,
1090 NDOPT_FLAG_SRCLINKADDR | NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU |
1091 NDOPT_FLAG_RDNSS | NDOPT_FLAG_DNSSL);
1092 if (error) {
1093 syslog(LOG_INFO,
1094 "<%s> ND option check failed for an RA from %s on %s",
1095 __func__,
1096 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1097 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex,
1098 ifnamebuf));
1099 return;
1100 }
1101
1102 /*
1103 * RA consistency check according to RFC 4861 6.2.7
1104 */
1105 ifi = if_indextoifinfo(pi->ipi6_ifindex);
1106 if (ifi->ifi_rainfo == NULL) {
1107 syslog(LOG_INFO,
1108 "<%s> received RA from %s on non-advertising"
1109 " interface(%s)",
1110 __func__,
1111 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1112 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex,
1113 ifnamebuf));
1114 goto done;
1115 }
1116 rai = ifi->ifi_rainfo;
1117 ifi->ifi_rainput++;
1118 syslog(LOG_DEBUG, "<%s> ifi->ifi_rainput = %" PRIu64, __func__,
1119 ifi->ifi_rainput);
1120
1121 /* Cur Hop Limit value */
1122 if (nra->nd_ra_curhoplimit && rai->rai_hoplimit &&
1123 nra->nd_ra_curhoplimit != rai->rai_hoplimit) {
1124 syslog(LOG_NOTICE,
1125 "CurHopLimit inconsistent on %s:"
1126 " %d from %s, %d from us",
1127 ifi->ifi_ifname, nra->nd_ra_curhoplimit,
1128 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1129 sizeof(ntopbuf)), rai->rai_hoplimit);
1130 inconsistent++;
1131 }
1132 /* M flag */
1133 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) !=
1134 rai->rai_managedflg) {
1135 syslog(LOG_NOTICE,
1136 "M flag inconsistent on %s:"
1137 " %s from %s, %s from us",
1138 ifi->ifi_ifname, on_off[!rai->rai_managedflg],
1139 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1140 sizeof(ntopbuf)), on_off[rai->rai_managedflg]);
1141 inconsistent++;
1142 }
1143 /* O flag */
1144 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) !=
1145 rai->rai_otherflg) {
1146 syslog(LOG_NOTICE,
1147 "O flag inconsistent on %s:"
1148 " %s from %s, %s from us",
1149 ifi->ifi_ifname, on_off[!rai->rai_otherflg],
1150 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1151 sizeof(ntopbuf)), on_off[rai->rai_otherflg]);
1152 inconsistent++;
1153 }
1154 #ifdef DRAFT_IETF_6MAN_IPV6ONLY_FLAG
1155 /* S "IPv6-Only" (Six, Silence-IPv4) flag */
1156 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_IPV6_ONLY) !=
1157 rai->rai_ipv6onlyflg) {
1158 syslog(LOG_NOTICE,
1159 "S flag inconsistent on %s:"
1160 " %s from %s, %s from us",
1161 ifi->ifi_ifname, on_off[!rai->rai_ipv6onlyflg],
1162 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1163 sizeof(ntopbuf)), on_off[rai->rai_ipv6onlyflg]);
1164 inconsistent++;
1165 }
1166 #endif
1167 /* Reachable Time */
1168 reachabletime = ntohl(nra->nd_ra_reachable);
1169 if (reachabletime && rai->rai_reachabletime &&
1170 reachabletime != rai->rai_reachabletime) {
1171 syslog(LOG_NOTICE,
1172 "ReachableTime inconsistent on %s:"
1173 " %d from %s, %d from us",
1174 ifi->ifi_ifname, reachabletime,
1175 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1176 sizeof(ntopbuf)), rai->rai_reachabletime);
1177 inconsistent++;
1178 }
1179 /* Retrans Timer */
1180 retranstimer = ntohl(nra->nd_ra_retransmit);
1181 if (retranstimer && rai->rai_retranstimer &&
1182 retranstimer != rai->rai_retranstimer) {
1183 syslog(LOG_NOTICE,
1184 "RetranceTimer inconsistent on %s:"
1185 " %d from %s, %d from us",
1186 ifi->ifi_ifname, retranstimer,
1187 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1188 sizeof(ntopbuf)), rai->rai_retranstimer);
1189 inconsistent++;
1190 }
1191 /* Values in the MTU options */
1192 if (ndopts.opt_mtu) {
1193 mtu = ntohl(ndopts.opt_mtu->nd_opt_mtu_mtu);
1194 if (mtu && rai->rai_linkmtu && mtu != rai->rai_linkmtu) {
1195 syslog(LOG_NOTICE,
1196 "MTU option value inconsistent on %s:"
1197 " %d from %s, %d from us",
1198 ifi->ifi_ifname, mtu,
1199 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1200 sizeof(ntopbuf)), rai->rai_linkmtu);
1201 inconsistent++;
1202 }
1203 }
1204 /* Preferred and Valid Lifetimes for prefixes */
1205 {
1206 struct nd_optlist *nol;
1207
1208 if (ndopts.opt_pi)
1209 if (prefix_check(ndopts.opt_pi, rai, from))
1210 inconsistent++;
1211
1212 TAILQ_FOREACH(nol, &ndopts.opt_list, nol_next)
1213 if (prefix_check((struct nd_opt_prefix_info *)nol->nol_opt,
1214 rai, from))
1215 inconsistent++;
1216 }
1217
1218 if (inconsistent)
1219 ifi->ifi_rainconsistent++;
1220
1221 done:
1222 free_ndopts(&ndopts);
1223 return;
1224 }
1225
1226 static uint32_t
udiff(uint32_t u,uint32_t v)1227 udiff(uint32_t u, uint32_t v)
1228 {
1229 return (u >= v ? u - v : v - u);
1230 }
1231
1232 /* return a non-zero value if the received prefix is inconsistent with ours */
1233 static int
prefix_check(struct nd_opt_prefix_info * pinfo,struct rainfo * rai,struct sockaddr_in6 * from)1234 prefix_check(struct nd_opt_prefix_info *pinfo,
1235 struct rainfo *rai, struct sockaddr_in6 *from)
1236 {
1237 struct ifinfo *ifi;
1238 uint32_t preferred_time, valid_time;
1239 struct prefix *pfx;
1240 int inconsistent = 0;
1241 char ntopbuf[INET6_ADDRSTRLEN];
1242 char prefixbuf[INET6_ADDRSTRLEN];
1243 struct timespec now;
1244
1245 #if 0 /* impossible */
1246 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION)
1247 return (0);
1248 #endif
1249 ifi = rai->rai_ifinfo;
1250 /*
1251 * log if the adveritsed prefix has link-local scope(sanity check?)
1252 */
1253 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix))
1254 syslog(LOG_INFO,
1255 "<%s> link-local prefix %s/%d is advertised "
1256 "from %s on %s",
1257 __func__,
1258 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1259 sizeof(prefixbuf)),
1260 pinfo->nd_opt_pi_prefix_len,
1261 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1262 sizeof(ntopbuf)), ifi->ifi_ifname);
1263
1264 if ((pfx = find_prefix(rai, &pinfo->nd_opt_pi_prefix,
1265 pinfo->nd_opt_pi_prefix_len)) == NULL) {
1266 syslog(LOG_INFO,
1267 "<%s> prefix %s/%d from %s on %s is not in our list",
1268 __func__,
1269 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1270 sizeof(prefixbuf)),
1271 pinfo->nd_opt_pi_prefix_len,
1272 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1273 sizeof(ntopbuf)), ifi->ifi_ifname);
1274 return (0);
1275 }
1276
1277 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time);
1278 if (pfx->pfx_pltimeexpire) {
1279 /*
1280 * The lifetime is decremented in real time, so we should
1281 * compare the expiration time.
1282 * (RFC 2461 Section 6.2.7.)
1283 * XXX: can we really expect that all routers on the link
1284 * have synchronized clocks?
1285 */
1286 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1287 preferred_time += now.tv_sec;
1288
1289 if (!pfx->pfx_timer && rai->rai_clockskew &&
1290 udiff(preferred_time, pfx->pfx_pltimeexpire) > rai->rai_clockskew) {
1291 syslog(LOG_INFO,
1292 "<%s> preferred lifetime for %s/%d"
1293 " (decr. in real time) inconsistent on %s:"
1294 " %" PRIu32 " from %s, %" PRIu32 " from us",
1295 __func__,
1296 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1297 sizeof(prefixbuf)),
1298 pinfo->nd_opt_pi_prefix_len,
1299 ifi->ifi_ifname, preferred_time,
1300 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1301 sizeof(ntopbuf)), pfx->pfx_pltimeexpire);
1302 inconsistent++;
1303 }
1304 } else if (!pfx->pfx_timer && preferred_time != pfx->pfx_preflifetime)
1305 syslog(LOG_INFO,
1306 "<%s> preferred lifetime for %s/%d"
1307 " inconsistent on %s:"
1308 " %d from %s, %d from us",
1309 __func__,
1310 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1311 sizeof(prefixbuf)),
1312 pinfo->nd_opt_pi_prefix_len,
1313 ifi->ifi_ifname, preferred_time,
1314 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1315 sizeof(ntopbuf)), pfx->pfx_preflifetime);
1316
1317 valid_time = ntohl(pinfo->nd_opt_pi_valid_time);
1318 if (pfx->pfx_vltimeexpire) {
1319 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1320 valid_time += now.tv_sec;
1321
1322 if (!pfx->pfx_timer && rai->rai_clockskew &&
1323 udiff(valid_time, pfx->pfx_vltimeexpire) > rai->rai_clockskew) {
1324 syslog(LOG_INFO,
1325 "<%s> valid lifetime for %s/%d"
1326 " (decr. in real time) inconsistent on %s:"
1327 " %d from %s, %" PRIu32 " from us",
1328 __func__,
1329 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1330 sizeof(prefixbuf)),
1331 pinfo->nd_opt_pi_prefix_len,
1332 ifi->ifi_ifname, preferred_time,
1333 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1334 sizeof(ntopbuf)), pfx->pfx_vltimeexpire);
1335 inconsistent++;
1336 }
1337 } else if (!pfx->pfx_timer && valid_time != pfx->pfx_validlifetime) {
1338 syslog(LOG_INFO,
1339 "<%s> valid lifetime for %s/%d"
1340 " inconsistent on %s:"
1341 " %d from %s, %d from us",
1342 __func__,
1343 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf,
1344 sizeof(prefixbuf)),
1345 pinfo->nd_opt_pi_prefix_len,
1346 ifi->ifi_ifname, valid_time,
1347 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf,
1348 sizeof(ntopbuf)), pfx->pfx_validlifetime);
1349 inconsistent++;
1350 }
1351
1352 return (inconsistent);
1353 }
1354
1355 struct prefix *
find_prefix(struct rainfo * rai,struct in6_addr * prefix,int plen)1356 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen)
1357 {
1358 struct prefix *pfx;
1359 int bytelen, bitlen;
1360 char bitmask;
1361
1362 TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) {
1363 if (plen != pfx->pfx_prefixlen)
1364 continue;
1365
1366 bytelen = plen / 8;
1367 bitlen = plen % 8;
1368 bitmask = 0xff << (8 - bitlen);
1369
1370 if (memcmp((void *)prefix, (void *)&pfx->pfx_prefix, bytelen))
1371 continue;
1372
1373 if (bitlen == 0 ||
1374 ((prefix->s6_addr[bytelen] & bitmask) ==
1375 (pfx->pfx_prefix.s6_addr[bytelen] & bitmask))) {
1376 return (pfx);
1377 }
1378 }
1379
1380 return (NULL);
1381 }
1382
1383 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */
1384 int
prefix_match(struct in6_addr * p0,int plen0,struct in6_addr * p1,int plen1)1385 prefix_match(struct in6_addr *p0, int plen0,
1386 struct in6_addr *p1, int plen1)
1387 {
1388 int bytelen, bitlen;
1389 char bitmask;
1390
1391 if (plen0 < plen1)
1392 return (0);
1393
1394 bytelen = plen1 / 8;
1395 bitlen = plen1 % 8;
1396 bitmask = 0xff << (8 - bitlen);
1397
1398 if (memcmp((void *)p0, (void *)p1, bytelen))
1399 return (0);
1400
1401 if (bitlen == 0 ||
1402 ((p0->s6_addr[bytelen] & bitmask) ==
1403 (p1->s6_addr[bytelen] & bitmask))) {
1404 return (1);
1405 }
1406
1407 return (0);
1408 }
1409
1410 static int
nd6_options(struct nd_opt_hdr * hdr,int limit,union nd_opt * ndopts,uint32_t optflags)1411 nd6_options(struct nd_opt_hdr *hdr, int limit,
1412 union nd_opt *ndopts, uint32_t optflags)
1413 {
1414 int optlen = 0;
1415
1416 for (; limit > 0; limit -= optlen) {
1417 if ((size_t)limit < sizeof(struct nd_opt_hdr)) {
1418 syslog(LOG_INFO, "<%s> short option header", __func__);
1419 goto bad;
1420 }
1421
1422 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen);
1423 if (hdr->nd_opt_len == 0) {
1424 syslog(LOG_INFO,
1425 "<%s> bad ND option length(0) (type = %d)",
1426 __func__, hdr->nd_opt_type);
1427 goto bad;
1428 }
1429 optlen = hdr->nd_opt_len << 3;
1430 if (optlen > limit) {
1431 syslog(LOG_INFO, "<%s> short option", __func__);
1432 goto bad;
1433 }
1434
1435 if (hdr->nd_opt_type > ND_OPT_MTU &&
1436 hdr->nd_opt_type != ND_OPT_RDNSS &&
1437 hdr->nd_opt_type != ND_OPT_DNSSL) {
1438 syslog(LOG_INFO, "<%s> unknown ND option(type %d)",
1439 __func__, hdr->nd_opt_type);
1440 continue;
1441 }
1442
1443 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) {
1444 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)",
1445 __func__, hdr->nd_opt_type);
1446 continue;
1447 }
1448
1449 /*
1450 * Option length check. Do it here for all fixed-length
1451 * options.
1452 */
1453 switch (hdr->nd_opt_type) {
1454 case ND_OPT_MTU:
1455 if (optlen == sizeof(struct nd_opt_mtu))
1456 break;
1457 goto skip;
1458 case ND_OPT_RDNSS:
1459 if (optlen >= 24 &&
1460 (optlen - sizeof(struct nd_opt_rdnss)) % 16 == 0)
1461 break;
1462 goto skip;
1463 case ND_OPT_DNSSL:
1464 if (optlen >= 16 &&
1465 (optlen - sizeof(struct nd_opt_dnssl)) % 8 == 0)
1466 break;
1467 goto skip;
1468 case ND_OPT_PREFIX_INFORMATION:
1469 if (optlen == sizeof(struct nd_opt_prefix_info))
1470 break;
1471 skip:
1472 syslog(LOG_INFO, "<%s> invalid option length",
1473 __func__);
1474 continue;
1475 }
1476
1477 switch (hdr->nd_opt_type) {
1478 case ND_OPT_TARGET_LINKADDR:
1479 case ND_OPT_REDIRECTED_HEADER:
1480 case ND_OPT_RDNSS:
1481 case ND_OPT_DNSSL:
1482 break; /* we don't care about these options */
1483 case ND_OPT_SOURCE_LINKADDR:
1484 case ND_OPT_MTU:
1485 if (ndopts->opt_array[hdr->nd_opt_type]) {
1486 syslog(LOG_INFO,
1487 "<%s> duplicated ND option (type = %d)",
1488 __func__, hdr->nd_opt_type);
1489 }
1490 ndopts->opt_array[hdr->nd_opt_type] = hdr;
1491 break;
1492 case ND_OPT_PREFIX_INFORMATION:
1493 {
1494 struct nd_optlist *nol;
1495
1496 if (ndopts->opt_pi == 0) {
1497 ndopts->opt_pi =
1498 (struct nd_opt_prefix_info *)hdr;
1499 continue;
1500 }
1501 nol = malloc(sizeof(*nol));
1502 if (nol == NULL) {
1503 syslog(LOG_ERR, "<%s> can't allocate memory",
1504 __func__);
1505 goto bad;
1506 }
1507 nol->nol_opt = hdr;
1508 TAILQ_INSERT_TAIL(&(ndopts->opt_list), nol, nol_next);
1509
1510 break;
1511 }
1512 default: /* impossible */
1513 break;
1514 }
1515 }
1516
1517 return (0);
1518
1519 bad:
1520 free_ndopts(ndopts);
1521
1522 return (-1);
1523 }
1524
1525 static void
free_ndopts(union nd_opt * ndopts)1526 free_ndopts(union nd_opt *ndopts)
1527 {
1528 struct nd_optlist *nol;
1529
1530 while ((nol = TAILQ_FIRST(&ndopts->opt_list)) != NULL) {
1531 TAILQ_REMOVE(&ndopts->opt_list, nol, nol_next);
1532 free(nol);
1533 }
1534 }
1535
1536 void
sock_open(struct sockinfo * s)1537 sock_open(struct sockinfo *s)
1538 {
1539 struct icmp6_filter filt;
1540 int on;
1541 /* XXX: should be max MTU attached to the node */
1542 static char answer[1500];
1543
1544 syslog(LOG_DEBUG, "<%s> enter", __func__);
1545
1546 if (s == NULL) {
1547 syslog(LOG_ERR, "<%s> internal error", __func__);
1548 exit(1);
1549 }
1550 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1551 CMSG_SPACE(sizeof(int));
1552 rcvcmsgbuf = (char *)malloc(rcvcmsgbuflen);
1553 if (rcvcmsgbuf == NULL) {
1554 syslog(LOG_ERR, "<%s> not enough core", __func__);
1555 exit(1);
1556 }
1557
1558 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1559 CMSG_SPACE(sizeof(int));
1560 sndcmsgbuf = (char *)malloc(sndcmsgbuflen);
1561 if (sndcmsgbuf == NULL) {
1562 syslog(LOG_ERR, "<%s> not enough core", __func__);
1563 exit(1);
1564 }
1565
1566 if ((s->si_fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
1567 syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno));
1568 exit(1);
1569 }
1570 /* specify to tell receiving interface */
1571 on = 1;
1572 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
1573 sizeof(on)) < 0) {
1574 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", __func__,
1575 strerror(errno));
1576 exit(1);
1577 }
1578 on = 1;
1579 /* specify to tell value of hoplimit field of received IP6 hdr */
1580 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
1581 sizeof(on)) < 0) {
1582 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", __func__,
1583 strerror(errno));
1584 exit(1);
1585 }
1586 ICMP6_FILTER_SETBLOCKALL(&filt);
1587 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt);
1588 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
1589 if (mcastif != NULL)
1590 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt);
1591
1592 if (setsockopt(s->si_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
1593 sizeof(filt)) < 0) {
1594 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s",
1595 __func__, strerror(errno));
1596 exit(1);
1597 }
1598
1599 /* initialize msghdr for receiving packets */
1600 rcviov[0].iov_base = (caddr_t)answer;
1601 rcviov[0].iov_len = sizeof(answer);
1602 rcvmhdr.msg_name = (caddr_t)&rcvfrom;
1603 rcvmhdr.msg_namelen = sizeof(rcvfrom);
1604 rcvmhdr.msg_iov = rcviov;
1605 rcvmhdr.msg_iovlen = 1;
1606 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
1607 rcvmhdr.msg_controllen = rcvcmsgbuflen;
1608
1609 /* initialize msghdr for sending packets */
1610 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
1611 sndmhdr.msg_iov = sndiov;
1612 sndmhdr.msg_iovlen = 1;
1613 sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
1614 sndmhdr.msg_controllen = sndcmsgbuflen;
1615
1616 return;
1617 }
1618
1619 /* open a routing socket to watch the routing table */
1620 static void
rtsock_open(struct sockinfo * s)1621 rtsock_open(struct sockinfo *s)
1622 {
1623 if (s == NULL) {
1624 syslog(LOG_ERR, "<%s> internal error", __func__);
1625 exit(1);
1626 }
1627 if ((s->si_fd = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) {
1628 syslog(LOG_ERR,
1629 "<%s> socket: %s", __func__, strerror(errno));
1630 exit(1);
1631 }
1632 }
1633
1634 struct ifinfo *
if_indextoifinfo(int idx)1635 if_indextoifinfo(int idx)
1636 {
1637 struct ifinfo *ifi;
1638 char *name, name0[IFNAMSIZ];
1639
1640 /* Check if the interface has a valid name or not. */
1641 if (if_indextoname(idx, name0) == NULL)
1642 return (NULL);
1643
1644 TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
1645 if (ifi->ifi_ifindex == idx)
1646 return (ifi);
1647 }
1648
1649 if (ifi != NULL)
1650 syslog(LOG_DEBUG, "<%s> ifi found (idx=%d)",
1651 __func__, idx);
1652 else
1653 syslog(LOG_DEBUG, "<%s> ifi not found (idx=%d)",
1654 __func__, idx);
1655
1656 return (NULL); /* search failed */
1657 }
1658
1659 void
ra_output(struct ifinfo * ifi)1660 ra_output(struct ifinfo *ifi)
1661 {
1662 int i;
1663 struct cmsghdr *cm;
1664 struct in6_pktinfo *pi;
1665 struct soliciter *sol;
1666 struct rainfo *rai;
1667
1668 switch (ifi->ifi_state) {
1669 case IFI_STATE_CONFIGURED:
1670 rai = ifi->ifi_rainfo;
1671 break;
1672 case IFI_STATE_TRANSITIVE:
1673 rai = ifi->ifi_rainfo_trans;
1674 break;
1675 case IFI_STATE_UNCONFIGURED:
1676 syslog(LOG_DEBUG, "<%s> %s is unconfigured. "
1677 "Skip sending RAs.",
1678 __func__, ifi->ifi_ifname);
1679 return;
1680 default:
1681 rai = NULL;
1682 }
1683 if (rai == NULL) {
1684 syslog(LOG_DEBUG, "<%s> rainfo is NULL on %s."
1685 "Skip sending RAs.",
1686 __func__, ifi->ifi_ifname);
1687 return;
1688 }
1689 if (!(ifi->ifi_flags & IFF_UP)) {
1690 syslog(LOG_DEBUG, "<%s> %s is not up. "
1691 "Skip sending RAs.",
1692 __func__, ifi->ifi_ifname);
1693 return;
1694 }
1695 /*
1696 * Check lifetime, ACCEPT_RTADV flag, and ip6.forwarding.
1697 *
1698 * (lifetime == 0) = output
1699 * (lifetime != 0 && (check_accept_rtadv()) = no output
1700 *
1701 * Basically, hosts MUST NOT send Router Advertisement
1702 * messages at any time (RFC 4861, Section 6.2.3). However, it
1703 * would sometimes be useful to allow hosts to advertise some
1704 * parameters such as prefix information and link MTU. Thus,
1705 * we allow hosts to invoke rtadvd only when router lifetime
1706 * (on every advertising interface) is explicitly set
1707 * zero. (see also the above section)
1708 */
1709 syslog(LOG_DEBUG,
1710 "<%s> check lifetime=%d, ACCEPT_RTADV=%d, ip6.forwarding=%d "
1711 "on %s", __func__,
1712 rai->rai_lifetime,
1713 check_accept_rtadv(ifi->ifi_ifindex),
1714 getinet6sysctl(IPV6CTL_FORWARDING),
1715 ifi->ifi_ifname);
1716
1717 if (rai->rai_lifetime != 0) {
1718 if (getinet6sysctl(IPV6CTL_FORWARDING) == 0) {
1719 syslog(LOG_ERR,
1720 "non-zero lifetime RA "
1721 "but net.inet6.ip6.forwarding=0. "
1722 "Ignored.");
1723 return;
1724 }
1725 if (check_accept_rtadv(ifi->ifi_ifindex)) {
1726 syslog(LOG_ERR,
1727 "non-zero lifetime RA "
1728 "on RA receiving interface %s."
1729 " Ignored.", ifi->ifi_ifname);
1730 return;
1731 }
1732 }
1733
1734 make_packet(rai); /* XXX: inefficient */
1735
1736 sndmhdr.msg_name = (caddr_t)&sin6_linklocal_allnodes;
1737 sndmhdr.msg_iov[0].iov_base = (caddr_t)rai->rai_ra_data;
1738 sndmhdr.msg_iov[0].iov_len = rai->rai_ra_datalen;
1739
1740 cm = CMSG_FIRSTHDR(&sndmhdr);
1741 /* specify the outgoing interface */
1742 cm->cmsg_level = IPPROTO_IPV6;
1743 cm->cmsg_type = IPV6_PKTINFO;
1744 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
1745 pi = (struct in6_pktinfo *)CMSG_DATA(cm);
1746 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/
1747 pi->ipi6_ifindex = ifi->ifi_ifindex;
1748
1749 /* specify the hop limit of the packet */
1750 {
1751 int hoplimit = 255;
1752
1753 cm = CMSG_NXTHDR(&sndmhdr, cm);
1754 cm->cmsg_level = IPPROTO_IPV6;
1755 cm->cmsg_type = IPV6_HOPLIMIT;
1756 cm->cmsg_len = CMSG_LEN(sizeof(int));
1757 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
1758 }
1759
1760 syslog(LOG_DEBUG,
1761 "<%s> send RA on %s, # of RS waitings = %d",
1762 __func__, ifi->ifi_ifname, ifi->ifi_rs_waitcount);
1763
1764 i = sendmsg(sock.si_fd, &sndmhdr, 0);
1765
1766 if (i < 0 || (size_t)i != rai->rai_ra_datalen) {
1767 if (i < 0) {
1768 syslog(LOG_ERR, "<%s> sendmsg on %s: %s",
1769 __func__, ifi->ifi_ifname,
1770 strerror(errno));
1771 }
1772 }
1773
1774 /*
1775 * unicast advertisements
1776 * XXX commented out. reason: though spec does not forbit it, unicast
1777 * advert does not really help
1778 */
1779 while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) {
1780 TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next);
1781 free(sol);
1782 }
1783
1784 /* update timestamp */
1785 clock_gettime(CLOCK_MONOTONIC_FAST, &ifi->ifi_ra_lastsent);
1786
1787 /* update counter */
1788 ifi->ifi_rs_waitcount = 0;
1789 ifi->ifi_raoutput++;
1790
1791 switch (ifi->ifi_state) {
1792 case IFI_STATE_CONFIGURED:
1793 if (ifi->ifi_burstcount > 0)
1794 ifi->ifi_burstcount--;
1795 break;
1796 case IFI_STATE_TRANSITIVE:
1797 ifi->ifi_burstcount--;
1798 if (ifi->ifi_burstcount == 0) {
1799 if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) {
1800 /* Initial burst finished. */
1801 if (ifi->ifi_rainfo_trans != NULL)
1802 ifi->ifi_rainfo_trans = NULL;
1803 }
1804
1805 /* Remove burst RA information */
1806 if (ifi->ifi_rainfo_trans != NULL) {
1807 rm_rainfo(ifi->ifi_rainfo_trans);
1808 ifi->ifi_rainfo_trans = NULL;
1809 }
1810
1811 if (ifi->ifi_rainfo != NULL) {
1812 /*
1813 * TRANSITIVE -> CONFIGURED
1814 *
1815 * After initial burst or transition from
1816 * one configuration to another,
1817 * ifi_rainfo always points to the next RA
1818 * information.
1819 */
1820 ifi->ifi_state = IFI_STATE_CONFIGURED;
1821 syslog(LOG_DEBUG,
1822 "<%s> ifname=%s marked as "
1823 "CONFIGURED.", __func__,
1824 ifi->ifi_ifname);
1825 } else {
1826 /*
1827 * TRANSITIVE -> UNCONFIGURED
1828 *
1829 * If ifi_rainfo points to NULL, this
1830 * interface is shutting down.
1831 *
1832 */
1833 int error;
1834
1835 ifi->ifi_state = IFI_STATE_UNCONFIGURED;
1836 syslog(LOG_DEBUG,
1837 "<%s> ifname=%s marked as "
1838 "UNCONFIGURED.", __func__,
1839 ifi->ifi_ifname);
1840 error = sock_mc_leave(&sock,
1841 ifi->ifi_ifindex);
1842 if (error)
1843 exit(1);
1844 }
1845 }
1846 break;
1847 }
1848 }
1849
1850 /* process RA timer */
1851 struct rtadvd_timer *
ra_timeout(void * arg)1852 ra_timeout(void *arg)
1853 {
1854 struct ifinfo *ifi;
1855
1856 ifi = (struct ifinfo *)arg;
1857 syslog(LOG_DEBUG, "<%s> RA timer on %s is expired",
1858 __func__, ifi->ifi_ifname);
1859
1860 ra_output(ifi);
1861
1862 return (ifi->ifi_ra_timer);
1863 }
1864
1865 /* update RA timer */
1866 void
ra_timer_update(void * arg,struct timespec * tm)1867 ra_timer_update(void *arg, struct timespec *tm)
1868 {
1869 uint16_t interval;
1870 struct rainfo *rai;
1871 struct ifinfo *ifi;
1872
1873 ifi = (struct ifinfo *)arg;
1874 rai = ifi->ifi_rainfo;
1875 interval = 0;
1876
1877 switch (ifi->ifi_state) {
1878 case IFI_STATE_UNCONFIGURED:
1879 return;
1880 break;
1881 case IFI_STATE_CONFIGURED:
1882 /*
1883 * Whenever a multicast advertisement is sent from
1884 * an interface, the timer is reset to a
1885 * uniformly-distributed random value between the
1886 * interface's configured MinRtrAdvInterval and
1887 * MaxRtrAdvInterval (RFC4861 6.2.4).
1888 */
1889 interval = rai->rai_mininterval;
1890 interval += arc4random_uniform(rai->rai_maxinterval -
1891 rai->rai_mininterval);
1892 break;
1893 case IFI_STATE_TRANSITIVE:
1894 /*
1895 * For the first few advertisements (up to
1896 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen
1897 * interval is greater than
1898 * MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer SHOULD be
1899 * set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. (RFC
1900 * 4861 6.2.4)
1901 *
1902 * In such cases, the router SHOULD transmit one or more
1903 * (but not more than MAX_FINAL_RTR_ADVERTISEMENTS) final
1904 * multicast Router Advertisements on the interface with a
1905 * Router Lifetime field of zero. (RFC 4861 6.2.5)
1906 */
1907 interval = ifi->ifi_burstinterval;
1908 break;
1909 }
1910
1911 tm->tv_sec = interval;
1912 tm->tv_nsec = 0;
1913
1914 syslog(LOG_DEBUG,
1915 "<%s> RA timer on %s is set to %ld:%ld",
1916 __func__, ifi->ifi_ifname,
1917 (long int)tm->tv_sec, (long int)tm->tv_nsec / 1000);
1918
1919 return;
1920 }
1921