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 85struct msghdr rcvmhdr; 86static char *rcvcmsgbuf; 87static size_t rcvcmsgbuflen; 88static char *sndcmsgbuf = NULL; 89static size_t sndcmsgbuflen; 90struct msghdr sndmhdr; 91struct iovec rcviov[2]; 92struct iovec sndiov[2]; 93struct sockaddr_in6 rcvfrom; 94static const char *pidfilename = _PATH_RTADVDPID; 95const char *conffile = _PATH_RTADVDCONF; 96static struct pidfh *pfh; 97static int dflag, sflag; 98static 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 105struct railist_head_t railist = 106 TAILQ_HEAD_INITIALIZER(railist); 107struct ifilist_head_t ifilist = 108 TAILQ_HEAD_INITIALIZER(ifilist); 109 110struct nd_optlist { 111 TAILQ_ENTRY(nd_optlist) nol_next; 112 struct nd_opt_hdr *nol_opt; 113}; 114union 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 141static 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 151static void rtadvd_shutdown(void); 152static void sock_open(struct sockinfo *); 153static void rtsock_open(struct sockinfo *); 154static void rtadvd_input(struct sockinfo *); 155static void rs_input(int, struct nd_router_solicit *, 156 struct in6_pktinfo *, struct sockaddr_in6 *); 157static void ra_input(int, struct nd_router_advert *, 158 struct in6_pktinfo *, struct sockaddr_in6 *); 159static int prefix_check(struct nd_opt_prefix_info *, struct rainfo *, 160 struct sockaddr_in6 *); 161static int nd6_options(struct nd_opt_hdr *, int, 162 union nd_opt *, uint32_t); 163static void free_ndopts(union nd_opt *); 164static void rtmsg_input(struct sockinfo *); 165static void set_short_delay(struct ifinfo *); 166static int check_accept_rtadv(int); 167 168static void 169usage(void) 170{ 171 172 fprintf(stderr, "usage: rtadvd [-dDfRs] " 173 "[-c configfile] [-C ctlsock] [-M ifname] [-p pidfile]\n"); 174 exit(1); 175} 176 177int 178main(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, nitems(set), 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 366static void 367rtadvd_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 457static void 458rtmsg_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 709void 710rtadvd_input(struct sockinfo *s) 711{ 712 ssize_t i; 713 int *hlimp = NULL; 714#ifdef OLDRAWSOCKET 715 struct ip6_hdr *ip; 716#endif 717 struct icmp6_hdr *icp; 718 int ifindex = 0; 719 struct cmsghdr *cm; 720 struct in6_pktinfo *pi = NULL; 721 char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; 722 struct in6_addr dst = in6addr_any; 723 struct ifinfo *ifi; 724 725 syslog(LOG_DEBUG, "<%s> enter", __func__); 726 727 if (s == NULL) { 728 syslog(LOG_ERR, "<%s> internal error", __func__); 729 exit(1); 730 } 731 /* 732 * Get message. We reset msg_controllen since the field could 733 * be modified if we had received a message before setting 734 * receive options. 735 */ 736 rcvmhdr.msg_controllen = rcvcmsgbuflen; 737 if ((i = recvmsg(s->si_fd, &rcvmhdr, 0)) < 0) 738 return; 739 740 /* extract optional information via Advanced API */ 741 for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr); 742 cm; 743 cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) { 744 if (cm->cmsg_level == IPPROTO_IPV6 && 745 cm->cmsg_type == IPV6_PKTINFO && 746 cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) { 747 pi = (struct in6_pktinfo *)(CMSG_DATA(cm)); 748 ifindex = pi->ipi6_ifindex; 749 dst = pi->ipi6_addr; 750 } 751 if (cm->cmsg_level == IPPROTO_IPV6 && 752 cm->cmsg_type == IPV6_HOPLIMIT && 753 cm->cmsg_len == CMSG_LEN(sizeof(int))) 754 hlimp = (int *)CMSG_DATA(cm); 755 } 756 if (ifindex == 0) { 757 syslog(LOG_ERR, "failed to get receiving interface"); 758 return; 759 } 760 if (hlimp == NULL) { 761 syslog(LOG_ERR, "failed to get receiving hop limit"); 762 return; 763 } 764 765 /* 766 * If we happen to receive data on an interface which is now gone 767 * or down, just discard the data. 768 */ 769 ifi = if_indextoifinfo(pi->ipi6_ifindex); 770 if (ifi == NULL || !(ifi->ifi_flags & IFF_UP)) { 771 syslog(LOG_INFO, 772 "<%s> received data on a disabled interface (%s)", 773 __func__, 774 (ifi == NULL) ? "[gone]" : ifi->ifi_ifname); 775 return; 776 } 777 778#ifdef OLDRAWSOCKET 779 if ((size_t)i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) { 780 syslog(LOG_ERR, 781 "packet size(%d) is too short", i); 782 return; 783 } 784 785 ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base; 786 icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */ 787#else 788 if ((size_t)i < sizeof(struct icmp6_hdr)) { 789 syslog(LOG_ERR, "packet size(%zd) is too short", i); 790 return; 791 } 792 793 icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base; 794#endif 795 796 switch (icp->icmp6_type) { 797 case ND_ROUTER_SOLICIT: 798 /* 799 * Message verification - RFC 4861 6.1.1 800 * XXX: these checks must be done in the kernel as well, 801 * but we can't completely rely on them. 802 */ 803 if (*hlimp != 255) { 804 syslog(LOG_NOTICE, 805 "RS with invalid hop limit(%d) " 806 "received from %s on %s", 807 *hlimp, 808 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 809 sizeof(ntopbuf)), 810 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 811 return; 812 } 813 if (icp->icmp6_code) { 814 syslog(LOG_NOTICE, 815 "RS with invalid ICMP6 code(%d) " 816 "received from %s on %s", 817 icp->icmp6_code, 818 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 819 sizeof(ntopbuf)), 820 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 821 return; 822 } 823 if ((size_t)i < sizeof(struct nd_router_solicit)) { 824 syslog(LOG_NOTICE, 825 "RS from %s on %s does not have enough " 826 "length (len = %zd)", 827 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 828 sizeof(ntopbuf)), 829 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 830 return; 831 } 832 rs_input(i, (struct nd_router_solicit *)icp, pi, &rcvfrom); 833 break; 834 case ND_ROUTER_ADVERT: 835 /* 836 * Message verification - RFC 4861 6.1.2 837 * XXX: there's the same dilemma as above... 838 */ 839 if (!IN6_IS_ADDR_LINKLOCAL(&rcvfrom.sin6_addr)) { 840 syslog(LOG_NOTICE, 841 "RA with non-linklocal source address " 842 "received from %s on %s", 843 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, 844 ntopbuf, sizeof(ntopbuf)), 845 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 846 return; 847 } 848 if (*hlimp != 255) { 849 syslog(LOG_NOTICE, 850 "RA with invalid hop limit(%d) " 851 "received from %s on %s", 852 *hlimp, 853 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 854 sizeof(ntopbuf)), 855 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 856 return; 857 } 858 if (icp->icmp6_code) { 859 syslog(LOG_NOTICE, 860 "RA with invalid ICMP6 code(%d) " 861 "received from %s on %s", 862 icp->icmp6_code, 863 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 864 sizeof(ntopbuf)), 865 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 866 return; 867 } 868 if ((size_t)i < sizeof(struct nd_router_advert)) { 869 syslog(LOG_NOTICE, 870 "RA from %s on %s does not have enough " 871 "length (len = %zd)", 872 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 873 sizeof(ntopbuf)), 874 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 875 return; 876 } 877 ra_input(i, (struct nd_router_advert *)icp, pi, &rcvfrom); 878 break; 879 case ICMP6_ROUTER_RENUMBERING: 880 if (mcastif == NULL) { 881 syslog(LOG_ERR, "received a router renumbering " 882 "message, but not allowed to be accepted"); 883 break; 884 } 885 rr_input(i, (struct icmp6_router_renum *)icp, pi, &rcvfrom, 886 &dst); 887 break; 888 default: 889 /* 890 * Note that this case is POSSIBLE, especially just 891 * after invocation of the daemon. This is because we 892 * could receive message after opening the socket and 893 * before setting ICMP6 type filter(see sock_open()). 894 */ 895 syslog(LOG_ERR, "invalid icmp type(%d)", icp->icmp6_type); 896 return; 897 } 898} 899 900static void 901rs_input(int len, struct nd_router_solicit *rs, 902 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 903{ 904 char ntopbuf[INET6_ADDRSTRLEN]; 905 char ifnamebuf[IFNAMSIZ]; 906 union nd_opt ndopts; 907 struct rainfo *rai; 908 struct ifinfo *ifi; 909 struct soliciter *sol; 910 911 syslog(LOG_DEBUG, 912 "<%s> RS received from %s on %s", 913 __func__, 914 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 915 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 916 917 /* ND option check */ 918 memset(&ndopts, 0, sizeof(ndopts)); 919 TAILQ_INIT(&ndopts.opt_list); 920 if (nd6_options((struct nd_opt_hdr *)(rs + 1), 921 len - sizeof(struct nd_router_solicit), 922 &ndopts, NDOPT_FLAG_SRCLINKADDR)) { 923 syslog(LOG_INFO, 924 "<%s> ND option check failed for an RS from %s on %s", 925 __func__, 926 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 927 sizeof(ntopbuf)), 928 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 929 return; 930 } 931 932 /* 933 * If the IP source address is the unspecified address, there 934 * must be no source link-layer address option in the message. 935 * (RFC 4861 6.1.1) 936 */ 937 if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) && 938 ndopts.opt_src_lladdr) { 939 syslog(LOG_INFO, 940 "<%s> RS from unspecified src on %s has a link-layer" 941 " address option", 942 __func__, if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 943 goto done; 944 } 945 946 ifi = if_indextoifinfo(pi->ipi6_ifindex); 947 if (ifi == NULL) { 948 syslog(LOG_INFO, 949 "<%s> if (idx=%d) not found. Why?", 950 __func__, pi->ipi6_ifindex); 951 goto done; 952 } 953 rai = ifi->ifi_rainfo; 954 if (rai == NULL) { 955 syslog(LOG_INFO, 956 "<%s> RS received on non advertising interface(%s)", 957 __func__, 958 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 959 goto done; 960 } 961 962 rai->rai_ifinfo->ifi_rsinput++; 963 964 /* 965 * Decide whether to send RA according to the rate-limit 966 * consideration. 967 */ 968 969 /* record sockaddr waiting for RA, if possible */ 970 sol = (struct soliciter *)malloc(sizeof(*sol)); 971 if (sol) { 972 sol->sol_addr = *from; 973 /* XXX RFC 2553 need clarification on flowinfo */ 974 sol->sol_addr.sin6_flowinfo = 0; 975 TAILQ_INSERT_TAIL(&rai->rai_soliciter, sol, sol_next); 976 } 977 978 /* 979 * If there is already a waiting RS packet, don't 980 * update the timer. 981 */ 982 if (ifi->ifi_rs_waitcount++) 983 goto done; 984 985 set_short_delay(ifi); 986 987 done: 988 free_ndopts(&ndopts); 989} 990 991static void 992set_short_delay(struct ifinfo *ifi) 993{ 994 long delay; /* must not be greater than 1000000 */ 995 struct timespec interval, now, min_delay, tm_tmp, *rest; 996 997 if (ifi->ifi_ra_timer == NULL) 998 return; 999 /* 1000 * Compute a random delay. If the computed value 1001 * corresponds to a time later than the time the next 1002 * multicast RA is scheduled to be sent, ignore the random 1003 * delay and send the advertisement at the 1004 * already-scheduled time. RFC 4861 6.2.6 1005 */ 1006 delay = arc4random_uniform(MAX_RA_DELAY_TIME); 1007 interval.tv_sec = 0; 1008 interval.tv_nsec = delay * 1000; 1009 rest = rtadvd_timer_rest(ifi->ifi_ra_timer); 1010 if (TS_CMP(rest, &interval, <)) { 1011 syslog(LOG_DEBUG, "<%s> random delay is larger than " 1012 "the rest of the current timer", __func__); 1013 interval = *rest; 1014 } 1015 1016 /* 1017 * If we sent a multicast Router Advertisement within 1018 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule 1019 * the advertisement to be sent at a time corresponding to 1020 * MIN_DELAY_BETWEEN_RAS plus the random value after the 1021 * previous advertisement was sent. 1022 */ 1023 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1024 TS_SUB(&now, &ifi->ifi_ra_lastsent, &tm_tmp); 1025 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS; 1026 min_delay.tv_nsec = 0; 1027 if (TS_CMP(&tm_tmp, &min_delay, <)) { 1028 TS_SUB(&min_delay, &tm_tmp, &min_delay); 1029 TS_ADD(&min_delay, &interval, &interval); 1030 } 1031 rtadvd_set_timer(&interval, ifi->ifi_ra_timer); 1032} 1033 1034static int 1035check_accept_rtadv(int idx) 1036{ 1037 struct ifinfo *ifi; 1038 1039 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1040 if (ifi->ifi_ifindex == idx) 1041 break; 1042 } 1043 if (ifi == NULL) { 1044 syslog(LOG_DEBUG, 1045 "<%s> if (idx=%d) not found. Why?", 1046 __func__, idx); 1047 return (0); 1048 } 1049 1050 /* 1051 * RA_RECV: ND6_IFF_ACCEPT_RTADV 1052 * RA_SEND: ip6.forwarding 1053 */ 1054 if (update_ifinfo_nd_flags(ifi) != 0) { 1055 syslog(LOG_ERR, "cannot get nd6 flags (idx=%d)", idx); 1056 return (0); 1057 } 1058 1059 return (ifi->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV); 1060} 1061 1062static void 1063ra_input(int len, struct nd_router_advert *nra, 1064 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 1065{ 1066 struct rainfo *rai; 1067 struct ifinfo *ifi; 1068 char ntopbuf[INET6_ADDRSTRLEN]; 1069 char ifnamebuf[IFNAMSIZ]; 1070 union nd_opt ndopts; 1071 const char *on_off[] = {"OFF", "ON"}; 1072 uint32_t reachabletime, retranstimer, mtu; 1073 int inconsistent = 0; 1074 int error; 1075 1076 syslog(LOG_DEBUG, "<%s> RA received from %s on %s", __func__, 1077 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 1078 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 1079 1080 /* ND option check */ 1081 memset(&ndopts, 0, sizeof(ndopts)); 1082 TAILQ_INIT(&ndopts.opt_list); 1083 error = nd6_options((struct nd_opt_hdr *)(nra + 1), 1084 len - sizeof(struct nd_router_advert), &ndopts, 1085 NDOPT_FLAG_SRCLINKADDR | NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU | 1086 NDOPT_FLAG_RDNSS | NDOPT_FLAG_DNSSL); 1087 if (error) { 1088 syslog(LOG_INFO, 1089 "<%s> ND option check failed for an RA from %s on %s", 1090 __func__, 1091 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1092 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1093 ifnamebuf)); 1094 return; 1095 } 1096 1097 /* 1098 * RA consistency check according to RFC 4861 6.2.7 1099 */ 1100 ifi = if_indextoifinfo(pi->ipi6_ifindex); 1101 if (ifi->ifi_rainfo == NULL) { 1102 syslog(LOG_INFO, 1103 "<%s> received RA from %s on non-advertising" 1104 " interface(%s)", 1105 __func__, 1106 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1107 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1108 ifnamebuf)); 1109 goto done; 1110 } 1111 rai = ifi->ifi_rainfo; 1112 ifi->ifi_rainput++; 1113 syslog(LOG_DEBUG, "<%s> ifi->ifi_rainput = %" PRIu64, __func__, 1114 ifi->ifi_rainput); 1115 1116 /* Cur Hop Limit value */ 1117 if (nra->nd_ra_curhoplimit && rai->rai_hoplimit && 1118 nra->nd_ra_curhoplimit != rai->rai_hoplimit) { 1119 syslog(LOG_NOTICE, 1120 "CurHopLimit inconsistent on %s:" 1121 " %d from %s, %d from us", 1122 ifi->ifi_ifname, nra->nd_ra_curhoplimit, 1123 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1124 sizeof(ntopbuf)), rai->rai_hoplimit); 1125 inconsistent++; 1126 } 1127 /* M flag */ 1128 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) != 1129 rai->rai_managedflg) { 1130 syslog(LOG_NOTICE, 1131 "M flag inconsistent on %s:" 1132 " %s from %s, %s from us", 1133 ifi->ifi_ifname, on_off[!rai->rai_managedflg], 1134 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1135 sizeof(ntopbuf)), on_off[rai->rai_managedflg]); 1136 inconsistent++; 1137 } 1138 /* O flag */ 1139 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) != 1140 rai->rai_otherflg) { 1141 syslog(LOG_NOTICE, 1142 "O flag inconsistent on %s:" 1143 " %s from %s, %s from us", 1144 ifi->ifi_ifname, on_off[!rai->rai_otherflg], 1145 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1146 sizeof(ntopbuf)), on_off[rai->rai_otherflg]); 1147 inconsistent++; 1148 } 1149#ifdef DRAFT_IETF_6MAN_IPV6ONLY_FLAG 1150 /* S "IPv6-Only" (Six, Silence-IPv4) flag */ 1151 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_IPV6_ONLY) != 1152 rai->rai_ipv6onlyflg) { 1153 syslog(LOG_NOTICE, 1154 "S flag inconsistent on %s:" 1155 " %s from %s, %s from us", 1156 ifi->ifi_ifname, on_off[!rai->rai_ipv6onlyflg], 1157 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1158 sizeof(ntopbuf)), on_off[rai->rai_ipv6onlyflg]); 1159 inconsistent++; 1160 } 1161#endif 1162 /* Reachable Time */ 1163 reachabletime = ntohl(nra->nd_ra_reachable); 1164 if (reachabletime && rai->rai_reachabletime && 1165 reachabletime != rai->rai_reachabletime) { 1166 syslog(LOG_NOTICE, 1167 "ReachableTime inconsistent on %s:" 1168 " %d from %s, %d from us", 1169 ifi->ifi_ifname, reachabletime, 1170 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1171 sizeof(ntopbuf)), rai->rai_reachabletime); 1172 inconsistent++; 1173 } 1174 /* Retrans Timer */ 1175 retranstimer = ntohl(nra->nd_ra_retransmit); 1176 if (retranstimer && rai->rai_retranstimer && 1177 retranstimer != rai->rai_retranstimer) { 1178 syslog(LOG_NOTICE, 1179 "RetranceTimer inconsistent on %s:" 1180 " %d from %s, %d from us", 1181 ifi->ifi_ifname, retranstimer, 1182 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1183 sizeof(ntopbuf)), rai->rai_retranstimer); 1184 inconsistent++; 1185 } 1186 /* Values in the MTU options */ 1187 if (ndopts.opt_mtu) { 1188 mtu = ntohl(ndopts.opt_mtu->nd_opt_mtu_mtu); 1189 if (mtu && rai->rai_linkmtu && mtu != rai->rai_linkmtu) { 1190 syslog(LOG_NOTICE, 1191 "MTU option value inconsistent on %s:" 1192 " %d from %s, %d from us", 1193 ifi->ifi_ifname, mtu, 1194 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1195 sizeof(ntopbuf)), rai->rai_linkmtu); 1196 inconsistent++; 1197 } 1198 } 1199 /* Preferred and Valid Lifetimes for prefixes */ 1200 { 1201 struct nd_optlist *nol; 1202 1203 if (ndopts.opt_pi) 1204 if (prefix_check(ndopts.opt_pi, rai, from)) 1205 inconsistent++; 1206 1207 TAILQ_FOREACH(nol, &ndopts.opt_list, nol_next) 1208 if (prefix_check((struct nd_opt_prefix_info *)nol->nol_opt, 1209 rai, from)) 1210 inconsistent++; 1211 } 1212 1213 if (inconsistent) 1214 ifi->ifi_rainconsistent++; 1215 1216 done: 1217 free_ndopts(&ndopts); 1218} 1219 1220static uint32_t 1221udiff(uint32_t u, uint32_t v) 1222{ 1223 return (u >= v ? u - v : v - u); 1224} 1225 1226/* return a non-zero value if the received prefix is inconsistent with ours */ 1227static int 1228prefix_check(struct nd_opt_prefix_info *pinfo, 1229 struct rainfo *rai, struct sockaddr_in6 *from) 1230{ 1231 struct ifinfo *ifi; 1232 uint32_t preferred_time, valid_time; 1233 struct prefix *pfx; 1234 int inconsistent = 0; 1235 char ntopbuf[INET6_ADDRSTRLEN]; 1236 char prefixbuf[INET6_ADDRSTRLEN]; 1237 struct timespec now; 1238 1239#if 0 /* impossible */ 1240 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION) 1241 return (0); 1242#endif 1243 ifi = rai->rai_ifinfo; 1244 /* 1245 * log if the adveritsed prefix has link-local scope(sanity check?) 1246 */ 1247 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) 1248 syslog(LOG_INFO, 1249 "<%s> link-local prefix %s/%d is advertised " 1250 "from %s on %s", 1251 __func__, 1252 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1253 sizeof(prefixbuf)), 1254 pinfo->nd_opt_pi_prefix_len, 1255 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1256 sizeof(ntopbuf)), ifi->ifi_ifname); 1257 1258 if ((pfx = find_prefix(rai, &pinfo->nd_opt_pi_prefix, 1259 pinfo->nd_opt_pi_prefix_len)) == NULL) { 1260 syslog(LOG_INFO, 1261 "<%s> prefix %s/%d from %s on %s is not in our list", 1262 __func__, 1263 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1264 sizeof(prefixbuf)), 1265 pinfo->nd_opt_pi_prefix_len, 1266 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1267 sizeof(ntopbuf)), ifi->ifi_ifname); 1268 return (0); 1269 } 1270 1271 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time); 1272 if (pfx->pfx_pltimeexpire) { 1273 /* 1274 * The lifetime is decremented in real time, so we should 1275 * compare the expiration time. 1276 * (RFC 2461 Section 6.2.7.) 1277 * XXX: can we really expect that all routers on the link 1278 * have synchronized clocks? 1279 */ 1280 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1281 preferred_time += now.tv_sec; 1282 1283 if (!pfx->pfx_timer && rai->rai_clockskew && 1284 udiff(preferred_time, pfx->pfx_pltimeexpire) > rai->rai_clockskew) { 1285 syslog(LOG_INFO, 1286 "<%s> preferred lifetime for %s/%d" 1287 " (decr. in real time) inconsistent on %s:" 1288 " %" PRIu32 " from %s, %" PRIu32 " from us", 1289 __func__, 1290 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1291 sizeof(prefixbuf)), 1292 pinfo->nd_opt_pi_prefix_len, 1293 ifi->ifi_ifname, preferred_time, 1294 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1295 sizeof(ntopbuf)), pfx->pfx_pltimeexpire); 1296 inconsistent++; 1297 } 1298 } else if (!pfx->pfx_timer && preferred_time != pfx->pfx_preflifetime) 1299 syslog(LOG_INFO, 1300 "<%s> preferred lifetime for %s/%d" 1301 " inconsistent on %s:" 1302 " %d from %s, %d from us", 1303 __func__, 1304 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1305 sizeof(prefixbuf)), 1306 pinfo->nd_opt_pi_prefix_len, 1307 ifi->ifi_ifname, preferred_time, 1308 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1309 sizeof(ntopbuf)), pfx->pfx_preflifetime); 1310 1311 valid_time = ntohl(pinfo->nd_opt_pi_valid_time); 1312 if (pfx->pfx_vltimeexpire) { 1313 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1314 valid_time += now.tv_sec; 1315 1316 if (!pfx->pfx_timer && rai->rai_clockskew && 1317 udiff(valid_time, pfx->pfx_vltimeexpire) > rai->rai_clockskew) { 1318 syslog(LOG_INFO, 1319 "<%s> valid lifetime for %s/%d" 1320 " (decr. in real time) inconsistent on %s:" 1321 " %d from %s, %" PRIu32 " from us", 1322 __func__, 1323 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1324 sizeof(prefixbuf)), 1325 pinfo->nd_opt_pi_prefix_len, 1326 ifi->ifi_ifname, preferred_time, 1327 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1328 sizeof(ntopbuf)), pfx->pfx_vltimeexpire); 1329 inconsistent++; 1330 } 1331 } else if (!pfx->pfx_timer && valid_time != pfx->pfx_validlifetime) { 1332 syslog(LOG_INFO, 1333 "<%s> valid lifetime for %s/%d" 1334 " inconsistent on %s:" 1335 " %d from %s, %d from us", 1336 __func__, 1337 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1338 sizeof(prefixbuf)), 1339 pinfo->nd_opt_pi_prefix_len, 1340 ifi->ifi_ifname, valid_time, 1341 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1342 sizeof(ntopbuf)), pfx->pfx_validlifetime); 1343 inconsistent++; 1344 } 1345 1346 return (inconsistent); 1347} 1348 1349struct prefix * 1350find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen) 1351{ 1352 struct prefix *pfx; 1353 int bytelen, bitlen; 1354 char bitmask; 1355 1356 TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) { 1357 if (plen != pfx->pfx_prefixlen) 1358 continue; 1359 1360 bytelen = plen / 8; 1361 bitlen = plen % 8; 1362 bitmask = 0xff << (8 - bitlen); 1363 1364 if (memcmp((void *)prefix, (void *)&pfx->pfx_prefix, bytelen)) 1365 continue; 1366 1367 if (bitlen == 0 || 1368 ((prefix->s6_addr[bytelen] & bitmask) == 1369 (pfx->pfx_prefix.s6_addr[bytelen] & bitmask))) { 1370 return (pfx); 1371 } 1372 } 1373 1374 return (NULL); 1375} 1376 1377/* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */ 1378int 1379prefix_match(struct in6_addr *p0, int plen0, 1380 struct in6_addr *p1, int plen1) 1381{ 1382 int bytelen, bitlen; 1383 char bitmask; 1384 1385 if (plen0 < plen1) 1386 return (0); 1387 1388 bytelen = plen1 / 8; 1389 bitlen = plen1 % 8; 1390 bitmask = 0xff << (8 - bitlen); 1391 1392 if (memcmp((void *)p0, (void *)p1, bytelen)) 1393 return (0); 1394 1395 if (bitlen == 0 || 1396 ((p0->s6_addr[bytelen] & bitmask) == 1397 (p1->s6_addr[bytelen] & bitmask))) { 1398 return (1); 1399 } 1400 1401 return (0); 1402} 1403 1404static int 1405nd6_options(struct nd_opt_hdr *hdr, int limit, 1406 union nd_opt *ndopts, uint32_t optflags) 1407{ 1408 int optlen = 0; 1409 1410 for (; limit > 0; limit -= optlen) { 1411 if ((size_t)limit < sizeof(struct nd_opt_hdr)) { 1412 syslog(LOG_INFO, "<%s> short option header", __func__); 1413 goto bad; 1414 } 1415 1416 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen); 1417 if (hdr->nd_opt_len == 0) { 1418 syslog(LOG_INFO, 1419 "<%s> bad ND option length(0) (type = %d)", 1420 __func__, hdr->nd_opt_type); 1421 goto bad; 1422 } 1423 optlen = hdr->nd_opt_len << 3; 1424 if (optlen > limit) { 1425 syslog(LOG_INFO, "<%s> short option", __func__); 1426 goto bad; 1427 } 1428 1429 if (hdr->nd_opt_type > ND_OPT_MTU && 1430 hdr->nd_opt_type != ND_OPT_RDNSS && 1431 hdr->nd_opt_type != ND_OPT_DNSSL) { 1432 syslog(LOG_INFO, "<%s> unknown ND option(type %d)", 1433 __func__, hdr->nd_opt_type); 1434 continue; 1435 } 1436 1437 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) { 1438 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)", 1439 __func__, hdr->nd_opt_type); 1440 continue; 1441 } 1442 1443 /* 1444 * Option length check. Do it here for all fixed-length 1445 * options. 1446 */ 1447 switch (hdr->nd_opt_type) { 1448 case ND_OPT_MTU: 1449 if (optlen == sizeof(struct nd_opt_mtu)) 1450 break; 1451 goto skip; 1452 case ND_OPT_RDNSS: 1453 if (optlen >= 24 && 1454 (optlen - sizeof(struct nd_opt_rdnss)) % 16 == 0) 1455 break; 1456 goto skip; 1457 case ND_OPT_DNSSL: 1458 if (optlen >= 16 && 1459 (optlen - sizeof(struct nd_opt_dnssl)) % 8 == 0) 1460 break; 1461 goto skip; 1462 case ND_OPT_PREFIX_INFORMATION: 1463 if (optlen == sizeof(struct nd_opt_prefix_info)) 1464 break; 1465skip: 1466 syslog(LOG_INFO, "<%s> invalid option length", 1467 __func__); 1468 continue; 1469 } 1470 1471 switch (hdr->nd_opt_type) { 1472 case ND_OPT_TARGET_LINKADDR: 1473 case ND_OPT_REDIRECTED_HEADER: 1474 case ND_OPT_RDNSS: 1475 case ND_OPT_DNSSL: 1476 break; /* we don't care about these options */ 1477 case ND_OPT_SOURCE_LINKADDR: 1478 case ND_OPT_MTU: 1479 if (ndopts->opt_array[hdr->nd_opt_type]) { 1480 syslog(LOG_INFO, 1481 "<%s> duplicated ND option (type = %d)", 1482 __func__, hdr->nd_opt_type); 1483 } 1484 ndopts->opt_array[hdr->nd_opt_type] = hdr; 1485 break; 1486 case ND_OPT_PREFIX_INFORMATION: 1487 { 1488 struct nd_optlist *nol; 1489 1490 if (ndopts->opt_pi == 0) { 1491 ndopts->opt_pi = 1492 (struct nd_opt_prefix_info *)hdr; 1493 continue; 1494 } 1495 nol = malloc(sizeof(*nol)); 1496 if (nol == NULL) { 1497 syslog(LOG_ERR, "<%s> can't allocate memory", 1498 __func__); 1499 goto bad; 1500 } 1501 nol->nol_opt = hdr; 1502 TAILQ_INSERT_TAIL(&(ndopts->opt_list), nol, nol_next); 1503 1504 break; 1505 } 1506 default: /* impossible */ 1507 break; 1508 } 1509 } 1510 1511 return (0); 1512 1513 bad: 1514 free_ndopts(ndopts); 1515 1516 return (-1); 1517} 1518 1519static void 1520free_ndopts(union nd_opt *ndopts) 1521{ 1522 struct nd_optlist *nol; 1523 1524 while ((nol = TAILQ_FIRST(&ndopts->opt_list)) != NULL) { 1525 TAILQ_REMOVE(&ndopts->opt_list, nol, nol_next); 1526 free(nol); 1527 } 1528} 1529 1530void 1531sock_open(struct sockinfo *s) 1532{ 1533 struct icmp6_filter filt; 1534 int on; 1535 /* XXX: should be max MTU attached to the node */ 1536 static char answer[1500]; 1537 1538 syslog(LOG_DEBUG, "<%s> enter", __func__); 1539 1540 if (s == NULL) { 1541 syslog(LOG_ERR, "<%s> internal error", __func__); 1542 exit(1); 1543 } 1544 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1545 CMSG_SPACE(sizeof(int)); 1546 rcvcmsgbuf = (char *)malloc(rcvcmsgbuflen); 1547 if (rcvcmsgbuf == NULL) { 1548 syslog(LOG_ERR, "<%s> not enough core", __func__); 1549 exit(1); 1550 } 1551 1552 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1553 CMSG_SPACE(sizeof(int)); 1554 sndcmsgbuf = (char *)malloc(sndcmsgbuflen); 1555 if (sndcmsgbuf == NULL) { 1556 syslog(LOG_ERR, "<%s> not enough core", __func__); 1557 exit(1); 1558 } 1559 1560 if ((s->si_fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) { 1561 syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno)); 1562 exit(1); 1563 } 1564 /* specify to tell receiving interface */ 1565 on = 1; 1566 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 1567 sizeof(on)) < 0) { 1568 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", __func__, 1569 strerror(errno)); 1570 exit(1); 1571 } 1572 on = 1; 1573 /* specify to tell value of hoplimit field of received IP6 hdr */ 1574 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 1575 sizeof(on)) < 0) { 1576 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", __func__, 1577 strerror(errno)); 1578 exit(1); 1579 } 1580 ICMP6_FILTER_SETBLOCKALL(&filt); 1581 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt); 1582 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt); 1583 if (mcastif != NULL) 1584 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt); 1585 1586 if (setsockopt(s->si_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, 1587 sizeof(filt)) < 0) { 1588 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s", 1589 __func__, strerror(errno)); 1590 exit(1); 1591 } 1592 1593 /* initialize msghdr for receiving packets */ 1594 rcviov[0].iov_base = (caddr_t)answer; 1595 rcviov[0].iov_len = sizeof(answer); 1596 rcvmhdr.msg_name = (caddr_t)&rcvfrom; 1597 rcvmhdr.msg_namelen = sizeof(rcvfrom); 1598 rcvmhdr.msg_iov = rcviov; 1599 rcvmhdr.msg_iovlen = 1; 1600 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf; 1601 rcvmhdr.msg_controllen = rcvcmsgbuflen; 1602 1603 /* initialize msghdr for sending packets */ 1604 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6); 1605 sndmhdr.msg_iov = sndiov; 1606 sndmhdr.msg_iovlen = 1; 1607 sndmhdr.msg_control = (caddr_t)sndcmsgbuf; 1608 sndmhdr.msg_controllen = sndcmsgbuflen; 1609} 1610 1611/* open a routing socket to watch the routing table */ 1612static void 1613rtsock_open(struct sockinfo *s) 1614{ 1615 if (s == NULL) { 1616 syslog(LOG_ERR, "<%s> internal error", __func__); 1617 exit(1); 1618 } 1619 if ((s->si_fd = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) { 1620 syslog(LOG_ERR, 1621 "<%s> socket: %s", __func__, strerror(errno)); 1622 exit(1); 1623 } 1624} 1625 1626struct ifinfo * 1627if_indextoifinfo(int idx) 1628{ 1629 struct ifinfo *ifi; 1630 char *name, name0[IFNAMSIZ]; 1631 1632 /* Check if the interface has a valid name or not. */ 1633 if (if_indextoname(idx, name0) == NULL) 1634 return (NULL); 1635 1636 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1637 if (ifi->ifi_ifindex == idx) 1638 return (ifi); 1639 } 1640 1641 if (ifi != NULL) 1642 syslog(LOG_DEBUG, "<%s> ifi found (idx=%d)", 1643 __func__, idx); 1644 else 1645 syslog(LOG_DEBUG, "<%s> ifi not found (idx=%d)", 1646 __func__, idx); 1647 1648 return (NULL); /* search failed */ 1649} 1650 1651void 1652ra_output(struct ifinfo *ifi) 1653{ 1654 int i; 1655 struct cmsghdr *cm; 1656 struct in6_pktinfo *pi; 1657 struct soliciter *sol; 1658 struct rainfo *rai; 1659 1660 switch (ifi->ifi_state) { 1661 case IFI_STATE_CONFIGURED: 1662 rai = ifi->ifi_rainfo; 1663 break; 1664 case IFI_STATE_TRANSITIVE: 1665 rai = ifi->ifi_rainfo_trans; 1666 break; 1667 case IFI_STATE_UNCONFIGURED: 1668 syslog(LOG_DEBUG, "<%s> %s is unconfigured. " 1669 "Skip sending RAs.", 1670 __func__, ifi->ifi_ifname); 1671 return; 1672 default: 1673 rai = NULL; 1674 } 1675 if (rai == NULL) { 1676 syslog(LOG_DEBUG, "<%s> rainfo is NULL on %s." 1677 "Skip sending RAs.", 1678 __func__, ifi->ifi_ifname); 1679 return; 1680 } 1681 if (!(ifi->ifi_flags & IFF_UP)) { 1682 syslog(LOG_DEBUG, "<%s> %s is not up. " 1683 "Skip sending RAs.", 1684 __func__, ifi->ifi_ifname); 1685 return; 1686 } 1687 /* 1688 * Check lifetime, ACCEPT_RTADV flag, and ip6.forwarding. 1689 * 1690 * (lifetime == 0) = output 1691 * (lifetime != 0 && (check_accept_rtadv()) = no output 1692 * 1693 * Basically, hosts MUST NOT send Router Advertisement 1694 * messages at any time (RFC 4861, Section 6.2.3). However, it 1695 * would sometimes be useful to allow hosts to advertise some 1696 * parameters such as prefix information and link MTU. Thus, 1697 * we allow hosts to invoke rtadvd only when router lifetime 1698 * (on every advertising interface) is explicitly set 1699 * zero. (see also the above section) 1700 */ 1701 syslog(LOG_DEBUG, 1702 "<%s> check lifetime=%d, ACCEPT_RTADV=%d, ip6.forwarding=%d " 1703 "on %s", __func__, 1704 rai->rai_lifetime, 1705 check_accept_rtadv(ifi->ifi_ifindex), 1706 getinet6sysctl(IPV6CTL_FORWARDING), 1707 ifi->ifi_ifname); 1708 1709 if (rai->rai_lifetime != 0) { 1710 if (getinet6sysctl(IPV6CTL_FORWARDING) == 0) { 1711 syslog(LOG_ERR, 1712 "non-zero lifetime RA " 1713 "but net.inet6.ip6.forwarding=0. " 1714 "Ignored."); 1715 return; 1716 } 1717 if (check_accept_rtadv(ifi->ifi_ifindex)) { 1718 syslog(LOG_ERR, 1719 "non-zero lifetime RA " 1720 "on RA receiving interface %s." 1721 " Ignored.", ifi->ifi_ifname); 1722 return; 1723 } 1724 } 1725 1726 make_packet(rai); /* XXX: inefficient */ 1727 1728 sndmhdr.msg_name = (caddr_t)&sin6_linklocal_allnodes; 1729 sndmhdr.msg_iov[0].iov_base = (caddr_t)rai->rai_ra_data; 1730 sndmhdr.msg_iov[0].iov_len = rai->rai_ra_datalen; 1731 1732 cm = CMSG_FIRSTHDR(&sndmhdr); 1733 /* specify the outgoing interface */ 1734 cm->cmsg_level = IPPROTO_IPV6; 1735 cm->cmsg_type = IPV6_PKTINFO; 1736 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); 1737 pi = (struct in6_pktinfo *)CMSG_DATA(cm); 1738 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/ 1739 pi->ipi6_ifindex = ifi->ifi_ifindex; 1740 1741 /* specify the hop limit of the packet */ 1742 { 1743 int hoplimit = 255; 1744 1745 cm = CMSG_NXTHDR(&sndmhdr, cm); 1746 cm->cmsg_level = IPPROTO_IPV6; 1747 cm->cmsg_type = IPV6_HOPLIMIT; 1748 cm->cmsg_len = CMSG_LEN(sizeof(int)); 1749 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int)); 1750 } 1751 1752 syslog(LOG_DEBUG, 1753 "<%s> send RA on %s, # of RS waitings = %d", 1754 __func__, ifi->ifi_ifname, ifi->ifi_rs_waitcount); 1755 1756 i = sendmsg(sock.si_fd, &sndmhdr, 0); 1757 1758 if (i < 0 || (size_t)i != rai->rai_ra_datalen) { 1759 if (i < 0) { 1760 syslog(LOG_ERR, "<%s> sendmsg on %s: %s", 1761 __func__, ifi->ifi_ifname, 1762 strerror(errno)); 1763 } 1764 } 1765 1766 /* 1767 * unicast advertisements 1768 * XXX commented out. reason: though spec does not forbit it, unicast 1769 * advert does not really help 1770 */ 1771 while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) { 1772 TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next); 1773 free(sol); 1774 } 1775 1776 /* update timestamp */ 1777 clock_gettime(CLOCK_MONOTONIC_FAST, &ifi->ifi_ra_lastsent); 1778 1779 /* update counter */ 1780 ifi->ifi_rs_waitcount = 0; 1781 ifi->ifi_raoutput++; 1782 1783 switch (ifi->ifi_state) { 1784 case IFI_STATE_CONFIGURED: 1785 if (ifi->ifi_burstcount > 0) 1786 ifi->ifi_burstcount--; 1787 break; 1788 case IFI_STATE_TRANSITIVE: 1789 ifi->ifi_burstcount--; 1790 if (ifi->ifi_burstcount == 0) { 1791 if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) { 1792 /* Initial burst finished. */ 1793 if (ifi->ifi_rainfo_trans != NULL) 1794 ifi->ifi_rainfo_trans = NULL; 1795 } 1796 1797 /* Remove burst RA information */ 1798 if (ifi->ifi_rainfo_trans != NULL) { 1799 rm_rainfo(ifi->ifi_rainfo_trans); 1800 ifi->ifi_rainfo_trans = NULL; 1801 } 1802 1803 if (ifi->ifi_rainfo != NULL) { 1804 /* 1805 * TRANSITIVE -> CONFIGURED 1806 * 1807 * After initial burst or transition from 1808 * one configuration to another, 1809 * ifi_rainfo always points to the next RA 1810 * information. 1811 */ 1812 ifi->ifi_state = IFI_STATE_CONFIGURED; 1813 syslog(LOG_DEBUG, 1814 "<%s> ifname=%s marked as " 1815 "CONFIGURED.", __func__, 1816 ifi->ifi_ifname); 1817 } else { 1818 /* 1819 * TRANSITIVE -> UNCONFIGURED 1820 * 1821 * If ifi_rainfo points to NULL, this 1822 * interface is shutting down. 1823 * 1824 */ 1825 int error; 1826 1827 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 1828 syslog(LOG_DEBUG, 1829 "<%s> ifname=%s marked as " 1830 "UNCONFIGURED.", __func__, 1831 ifi->ifi_ifname); 1832 error = sock_mc_leave(&sock, 1833 ifi->ifi_ifindex); 1834 if (error) 1835 exit(1); 1836 } 1837 } 1838 break; 1839 } 1840} 1841 1842/* process RA timer */ 1843struct rtadvd_timer * 1844ra_timeout(void *arg) 1845{ 1846 struct ifinfo *ifi; 1847 1848 ifi = (struct ifinfo *)arg; 1849 syslog(LOG_DEBUG, "<%s> RA timer on %s is expired", 1850 __func__, ifi->ifi_ifname); 1851 1852 ra_output(ifi); 1853 1854 return (ifi->ifi_ra_timer); 1855} 1856 1857/* update RA timer */ 1858void 1859ra_timer_update(void *arg, struct timespec *tm) 1860{ 1861 uint16_t interval; 1862 struct rainfo *rai; 1863 struct ifinfo *ifi; 1864 1865 ifi = (struct ifinfo *)arg; 1866 rai = ifi->ifi_rainfo; 1867 interval = 0; 1868 1869 switch (ifi->ifi_state) { 1870 case IFI_STATE_UNCONFIGURED: 1871 return; 1872 break; 1873 case IFI_STATE_CONFIGURED: 1874 /* 1875 * Whenever a multicast advertisement is sent from 1876 * an interface, the timer is reset to a 1877 * uniformly-distributed random value between the 1878 * interface's configured MinRtrAdvInterval and 1879 * MaxRtrAdvInterval (RFC4861 6.2.4). 1880 */ 1881 interval = rai->rai_mininterval; 1882 interval += arc4random_uniform(rai->rai_maxinterval - 1883 rai->rai_mininterval); 1884 break; 1885 case IFI_STATE_TRANSITIVE: 1886 /* 1887 * For the first few advertisements (up to 1888 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen 1889 * interval is greater than 1890 * MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer SHOULD be 1891 * set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. (RFC 1892 * 4861 6.2.4) 1893 * 1894 * In such cases, the router SHOULD transmit one or more 1895 * (but not more than MAX_FINAL_RTR_ADVERTISEMENTS) final 1896 * multicast Router Advertisements on the interface with a 1897 * Router Lifetime field of zero. (RFC 4861 6.2.5) 1898 */ 1899 interval = ifi->ifi_burstinterval; 1900 break; 1901 } 1902 1903 tm->tv_sec = interval; 1904 tm->tv_nsec = 0; 1905 1906 syslog(LOG_DEBUG, 1907 "<%s> RA timer on %s is set to %ld:%ld", 1908 __func__, ifi->ifi_ifname, 1909 (long int)tm->tv_sec, (long int)tm->tv_nsec / 1000); 1910} 1911