rtadvd.c revision 290149
1/* $FreeBSD: stable/10/usr.sbin/rtadvd/rtadvd.c 290149 2015-10-29 16:53:34Z delphij $ */ 2/* $KAME: rtadvd.c,v 1.82 2003/08/05 12:34:23 itojun Exp $ */ 3 4/* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#include <sys/param.h> 35#include <sys/ioctl.h> 36#include <sys/socket.h> 37#include <sys/uio.h> 38#include <sys/queue.h> 39#include <sys/stat.h> 40#include <sys/sysctl.h> 41 42#include <net/if.h> 43#include <net/if_types.h> 44#include <net/if_media.h> 45#include <net/if_dl.h> 46#include <net/route.h> 47#include <netinet/in.h> 48#include <netinet/ip6.h> 49#include <netinet6/ip6_var.h> 50#include <netinet/icmp6.h> 51 52#include <arpa/inet.h> 53 54#include <net/if_var.h> 55#include <netinet/in_var.h> 56#include <netinet6/nd6.h> 57 58#include <time.h> 59#include <unistd.h> 60#include <stdio.h> 61#include <err.h> 62#include <errno.h> 63#include <inttypes.h> 64#include <libutil.h> 65#include <netdb.h> 66#include <signal.h> 67#include <string.h> 68#include <stdlib.h> 69#include <syslog.h> 70#include <poll.h> 71 72#include "pathnames.h" 73#include "rtadvd.h" 74#include "if.h" 75#include "rrenum.h" 76#include "advcap.h" 77#include "timer_subr.h" 78#include "timer.h" 79#include "config.h" 80#include "control.h" 81#include "control_server.h" 82 83#define RTADV_TYPE2BITMASK(type) (0x1 << type) 84 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, 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 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 return; 709} 710 711void 712rtadvd_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 904static void 905rs_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 996static void 997set_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 1039static int 1040check_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#if (__FreeBSD_version < 900000) 1055 /* 1056 * RA_RECV: !ip6.forwarding && ip6.accept_rtadv 1057 * RA_SEND: ip6.forwarding 1058 */ 1059 return ((getinet6sysctl(IPV6CTL_FORWARDING) == 0) && 1060 (getinet6sysctl(IPV6CTL_ACCEPT_RTADV) == 1)); 1061#else 1062 /* 1063 * RA_RECV: ND6_IFF_ACCEPT_RTADV 1064 * RA_SEND: ip6.forwarding 1065 */ 1066 if (update_ifinfo_nd_flags(ifi) != 0) { 1067 syslog(LOG_ERR, "cannot get nd6 flags (idx=%d)", idx); 1068 return (0); 1069 } 1070 1071 return (ifi->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV); 1072#endif 1073} 1074 1075static void 1076ra_input(int len, struct nd_router_advert *nra, 1077 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 1078{ 1079 struct rainfo *rai; 1080 struct ifinfo *ifi; 1081 char ntopbuf[INET6_ADDRSTRLEN]; 1082 char ifnamebuf[IFNAMSIZ]; 1083 union nd_opt ndopts; 1084 const char *on_off[] = {"OFF", "ON"}; 1085 uint32_t reachabletime, retranstimer, mtu; 1086 int inconsistent = 0; 1087 int error; 1088 1089 syslog(LOG_DEBUG, "<%s> RA received from %s on %s", __func__, 1090 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 1091 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 1092 1093 /* ND option check */ 1094 memset(&ndopts, 0, sizeof(ndopts)); 1095 TAILQ_INIT(&ndopts.opt_list); 1096 error = nd6_options((struct nd_opt_hdr *)(nra + 1), 1097 len - sizeof(struct nd_router_advert), &ndopts, 1098 NDOPT_FLAG_SRCLINKADDR | NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU | 1099 NDOPT_FLAG_RDNSS | NDOPT_FLAG_DNSSL); 1100 if (error) { 1101 syslog(LOG_INFO, 1102 "<%s> ND option check failed for an RA from %s on %s", 1103 __func__, 1104 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1105 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1106 ifnamebuf)); 1107 return; 1108 } 1109 1110 /* 1111 * RA consistency check according to RFC 4861 6.2.7 1112 */ 1113 ifi = if_indextoifinfo(pi->ipi6_ifindex); 1114 if (ifi->ifi_rainfo == NULL) { 1115 syslog(LOG_INFO, 1116 "<%s> received RA from %s on non-advertising" 1117 " interface(%s)", 1118 __func__, 1119 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1120 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1121 ifnamebuf)); 1122 goto done; 1123 } 1124 rai = ifi->ifi_rainfo; 1125 ifi->ifi_rainput++; 1126 syslog(LOG_DEBUG, "<%s> ifi->ifi_rainput = %" PRIu64, __func__, 1127 ifi->ifi_rainput); 1128 1129 /* Cur Hop Limit value */ 1130 if (nra->nd_ra_curhoplimit && rai->rai_hoplimit && 1131 nra->nd_ra_curhoplimit != rai->rai_hoplimit) { 1132 syslog(LOG_NOTICE, 1133 "CurHopLimit inconsistent on %s:" 1134 " %d from %s, %d from us", 1135 ifi->ifi_ifname, nra->nd_ra_curhoplimit, 1136 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1137 sizeof(ntopbuf)), rai->rai_hoplimit); 1138 inconsistent++; 1139 } 1140 /* M flag */ 1141 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) != 1142 rai->rai_managedflg) { 1143 syslog(LOG_NOTICE, 1144 "M flag inconsistent on %s:" 1145 " %s from %s, %s from us", 1146 ifi->ifi_ifname, on_off[!rai->rai_managedflg], 1147 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1148 sizeof(ntopbuf)), on_off[rai->rai_managedflg]); 1149 inconsistent++; 1150 } 1151 /* O flag */ 1152 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) != 1153 rai->rai_otherflg) { 1154 syslog(LOG_NOTICE, 1155 "O flag inconsistent on %s:" 1156 " %s from %s, %s from us", 1157 ifi->ifi_ifname, on_off[!rai->rai_otherflg], 1158 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1159 sizeof(ntopbuf)), on_off[rai->rai_otherflg]); 1160 inconsistent++; 1161 } 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 return; 1219} 1220 1221static uint32_t 1222udiff(uint32_t u, uint32_t v) 1223{ 1224 return (u >= v ? u - v : v - u); 1225} 1226 1227/* return a non-zero value if the received prefix is inconsitent with ours */ 1228static int 1229prefix_check(struct nd_opt_prefix_info *pinfo, 1230 struct rainfo *rai, struct sockaddr_in6 *from) 1231{ 1232 struct ifinfo *ifi; 1233 uint32_t preferred_time, valid_time; 1234 struct prefix *pfx; 1235 int inconsistent = 0; 1236 char ntopbuf[INET6_ADDRSTRLEN]; 1237 char prefixbuf[INET6_ADDRSTRLEN]; 1238 struct timespec now; 1239 1240#if 0 /* impossible */ 1241 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION) 1242 return (0); 1243#endif 1244 ifi = rai->rai_ifinfo; 1245 /* 1246 * log if the adveritsed prefix has link-local scope(sanity check?) 1247 */ 1248 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) 1249 syslog(LOG_INFO, 1250 "<%s> link-local prefix %s/%d is advertised " 1251 "from %s on %s", 1252 __func__, 1253 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1254 sizeof(prefixbuf)), 1255 pinfo->nd_opt_pi_prefix_len, 1256 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1257 sizeof(ntopbuf)), ifi->ifi_ifname); 1258 1259 if ((pfx = find_prefix(rai, &pinfo->nd_opt_pi_prefix, 1260 pinfo->nd_opt_pi_prefix_len)) == NULL) { 1261 syslog(LOG_INFO, 1262 "<%s> prefix %s/%d from %s on %s is not in our list", 1263 __func__, 1264 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1265 sizeof(prefixbuf)), 1266 pinfo->nd_opt_pi_prefix_len, 1267 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1268 sizeof(ntopbuf)), ifi->ifi_ifname); 1269 return (0); 1270 } 1271 1272 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time); 1273 if (pfx->pfx_pltimeexpire) { 1274 /* 1275 * The lifetime is decremented in real time, so we should 1276 * compare the expiration time. 1277 * (RFC 2461 Section 6.2.7.) 1278 * XXX: can we really expect that all routers on the link 1279 * have synchronized clocks? 1280 */ 1281 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1282 preferred_time += now.tv_sec; 1283 1284 if (!pfx->pfx_timer && rai->rai_clockskew && 1285 udiff(preferred_time, pfx->pfx_pltimeexpire) > rai->rai_clockskew) { 1286 syslog(LOG_INFO, 1287 "<%s> preferred lifetime for %s/%d" 1288 " (decr. in real time) inconsistent on %s:" 1289 " %" PRIu32 " from %s, %" PRIu32 " from us", 1290 __func__, 1291 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1292 sizeof(prefixbuf)), 1293 pinfo->nd_opt_pi_prefix_len, 1294 ifi->ifi_ifname, preferred_time, 1295 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1296 sizeof(ntopbuf)), pfx->pfx_pltimeexpire); 1297 inconsistent++; 1298 } 1299 } else if (!pfx->pfx_timer && preferred_time != pfx->pfx_preflifetime) 1300 syslog(LOG_INFO, 1301 "<%s> preferred lifetime for %s/%d" 1302 " inconsistent on %s:" 1303 " %d from %s, %d from us", 1304 __func__, 1305 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1306 sizeof(prefixbuf)), 1307 pinfo->nd_opt_pi_prefix_len, 1308 ifi->ifi_ifname, preferred_time, 1309 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1310 sizeof(ntopbuf)), pfx->pfx_preflifetime); 1311 1312 valid_time = ntohl(pinfo->nd_opt_pi_valid_time); 1313 if (pfx->pfx_vltimeexpire) { 1314 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1315 valid_time += now.tv_sec; 1316 1317 if (!pfx->pfx_timer && rai->rai_clockskew && 1318 udiff(valid_time, pfx->pfx_vltimeexpire) > rai->rai_clockskew) { 1319 syslog(LOG_INFO, 1320 "<%s> valid lifetime for %s/%d" 1321 " (decr. in real time) inconsistent on %s:" 1322 " %d from %s, %" PRIu32 " from us", 1323 __func__, 1324 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1325 sizeof(prefixbuf)), 1326 pinfo->nd_opt_pi_prefix_len, 1327 ifi->ifi_ifname, preferred_time, 1328 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1329 sizeof(ntopbuf)), pfx->pfx_vltimeexpire); 1330 inconsistent++; 1331 } 1332 } else if (!pfx->pfx_timer && valid_time != pfx->pfx_validlifetime) { 1333 syslog(LOG_INFO, 1334 "<%s> valid lifetime for %s/%d" 1335 " inconsistent on %s:" 1336 " %d from %s, %d from us", 1337 __func__, 1338 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1339 sizeof(prefixbuf)), 1340 pinfo->nd_opt_pi_prefix_len, 1341 ifi->ifi_ifname, valid_time, 1342 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1343 sizeof(ntopbuf)), pfx->pfx_validlifetime); 1344 inconsistent++; 1345 } 1346 1347 return (inconsistent); 1348} 1349 1350struct prefix * 1351find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen) 1352{ 1353 struct prefix *pfx; 1354 int bytelen, bitlen; 1355 char bitmask; 1356 1357 TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) { 1358 if (plen != pfx->pfx_prefixlen) 1359 continue; 1360 1361 bytelen = plen / 8; 1362 bitlen = plen % 8; 1363 bitmask = 0xff << (8 - bitlen); 1364 1365 if (memcmp((void *)prefix, (void *)&pfx->pfx_prefix, bytelen)) 1366 continue; 1367 1368 if (bitlen == 0 || 1369 ((prefix->s6_addr[bytelen] & bitmask) == 1370 (pfx->pfx_prefix.s6_addr[bytelen] & bitmask))) { 1371 return (pfx); 1372 } 1373 } 1374 1375 return (NULL); 1376} 1377 1378/* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */ 1379int 1380prefix_match(struct in6_addr *p0, int plen0, 1381 struct in6_addr *p1, int plen1) 1382{ 1383 int bytelen, bitlen; 1384 char bitmask; 1385 1386 if (plen0 < plen1) 1387 return (0); 1388 1389 bytelen = plen1 / 8; 1390 bitlen = plen1 % 8; 1391 bitmask = 0xff << (8 - bitlen); 1392 1393 if (memcmp((void *)p0, (void *)p1, bytelen)) 1394 return (0); 1395 1396 if (bitlen == 0 || 1397 ((p0->s6_addr[bytelen] & bitmask) == 1398 (p1->s6_addr[bytelen] & bitmask))) { 1399 return (1); 1400 } 1401 1402 return (0); 1403} 1404 1405static int 1406nd6_options(struct nd_opt_hdr *hdr, int limit, 1407 union nd_opt *ndopts, uint32_t optflags) 1408{ 1409 int optlen = 0; 1410 1411 for (; limit > 0; limit -= optlen) { 1412 if ((size_t)limit < sizeof(struct nd_opt_hdr)) { 1413 syslog(LOG_INFO, "<%s> short option header", __func__); 1414 goto bad; 1415 } 1416 1417 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen); 1418 if (hdr->nd_opt_len == 0) { 1419 syslog(LOG_INFO, 1420 "<%s> bad ND option length(0) (type = %d)", 1421 __func__, hdr->nd_opt_type); 1422 goto bad; 1423 } 1424 optlen = hdr->nd_opt_len << 3; 1425 if (optlen > limit) { 1426 syslog(LOG_INFO, "<%s> short option", __func__); 1427 goto bad; 1428 } 1429 1430 if (hdr->nd_opt_type > ND_OPT_MTU && 1431 hdr->nd_opt_type != ND_OPT_RDNSS && 1432 hdr->nd_opt_type != ND_OPT_DNSSL) { 1433 syslog(LOG_INFO, "<%s> unknown ND option(type %d)", 1434 __func__, hdr->nd_opt_type); 1435 continue; 1436 } 1437 1438 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) { 1439 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)", 1440 __func__, hdr->nd_opt_type); 1441 continue; 1442 } 1443 1444 /* 1445 * Option length check. Do it here for all fixed-length 1446 * options. 1447 */ 1448 switch (hdr->nd_opt_type) { 1449 case ND_OPT_MTU: 1450 if (optlen == sizeof(struct nd_opt_mtu)) 1451 break; 1452 goto skip; 1453 case ND_OPT_RDNSS: 1454 if (optlen >= 24 && 1455 (optlen - sizeof(struct nd_opt_rdnss)) % 16 == 0) 1456 break; 1457 goto skip; 1458 case ND_OPT_DNSSL: 1459 if (optlen >= 16 && 1460 (optlen - sizeof(struct nd_opt_dnssl)) % 8 == 0) 1461 break; 1462 goto skip; 1463 case ND_OPT_PREFIX_INFORMATION: 1464 if (optlen == sizeof(struct nd_opt_prefix_info)) 1465 break; 1466skip: 1467 syslog(LOG_INFO, "<%s> invalid option length", 1468 __func__); 1469 continue; 1470 } 1471 1472 switch (hdr->nd_opt_type) { 1473 case ND_OPT_TARGET_LINKADDR: 1474 case ND_OPT_REDIRECTED_HEADER: 1475 case ND_OPT_RDNSS: 1476 case ND_OPT_DNSSL: 1477 break; /* we don't care about these options */ 1478 case ND_OPT_SOURCE_LINKADDR: 1479 case ND_OPT_MTU: 1480 if (ndopts->opt_array[hdr->nd_opt_type]) { 1481 syslog(LOG_INFO, 1482 "<%s> duplicated ND option (type = %d)", 1483 __func__, hdr->nd_opt_type); 1484 } 1485 ndopts->opt_array[hdr->nd_opt_type] = hdr; 1486 break; 1487 case ND_OPT_PREFIX_INFORMATION: 1488 { 1489 struct nd_optlist *nol; 1490 1491 if (ndopts->opt_pi == 0) { 1492 ndopts->opt_pi = 1493 (struct nd_opt_prefix_info *)hdr; 1494 continue; 1495 } 1496 nol = malloc(sizeof(*nol)); 1497 if (nol == NULL) { 1498 syslog(LOG_ERR, "<%s> can't allocate memory", 1499 __func__); 1500 goto bad; 1501 } 1502 nol->nol_opt = hdr; 1503 TAILQ_INSERT_TAIL(&(ndopts->opt_list), nol, nol_next); 1504 1505 break; 1506 } 1507 default: /* impossible */ 1508 break; 1509 } 1510 } 1511 1512 return (0); 1513 1514 bad: 1515 free_ndopts(ndopts); 1516 1517 return (-1); 1518} 1519 1520static void 1521free_ndopts(union nd_opt *ndopts) 1522{ 1523 struct nd_optlist *nol; 1524 1525 while ((nol = TAILQ_FIRST(&ndopts->opt_list)) != NULL) { 1526 TAILQ_REMOVE(&ndopts->opt_list, nol, nol_next); 1527 free(nol); 1528 } 1529} 1530 1531void 1532sock_open(struct sockinfo *s) 1533{ 1534 struct icmp6_filter filt; 1535 int on; 1536 /* XXX: should be max MTU attached to the node */ 1537 static char answer[1500]; 1538 1539 syslog(LOG_DEBUG, "<%s> enter", __func__); 1540 1541 if (s == NULL) { 1542 syslog(LOG_ERR, "<%s> internal error", __func__); 1543 exit(1); 1544 } 1545 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1546 CMSG_SPACE(sizeof(int)); 1547 rcvcmsgbuf = (char *)malloc(rcvcmsgbuflen); 1548 if (rcvcmsgbuf == NULL) { 1549 syslog(LOG_ERR, "<%s> not enough core", __func__); 1550 exit(1); 1551 } 1552 1553 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1554 CMSG_SPACE(sizeof(int)); 1555 sndcmsgbuf = (char *)malloc(sndcmsgbuflen); 1556 if (sndcmsgbuf == NULL) { 1557 syslog(LOG_ERR, "<%s> not enough core", __func__); 1558 exit(1); 1559 } 1560 1561 if ((s->si_fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) { 1562 syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno)); 1563 exit(1); 1564 } 1565 /* specify to tell receiving interface */ 1566 on = 1; 1567 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 1568 sizeof(on)) < 0) { 1569 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", __func__, 1570 strerror(errno)); 1571 exit(1); 1572 } 1573 on = 1; 1574 /* specify to tell value of hoplimit field of received IP6 hdr */ 1575 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 1576 sizeof(on)) < 0) { 1577 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", __func__, 1578 strerror(errno)); 1579 exit(1); 1580 } 1581 ICMP6_FILTER_SETBLOCKALL(&filt); 1582 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt); 1583 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt); 1584 if (mcastif != NULL) 1585 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt); 1586 1587 if (setsockopt(s->si_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, 1588 sizeof(filt)) < 0) { 1589 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s", 1590 __func__, strerror(errno)); 1591 exit(1); 1592 } 1593 1594 /* initialize msghdr for receiving packets */ 1595 rcviov[0].iov_base = (caddr_t)answer; 1596 rcviov[0].iov_len = sizeof(answer); 1597 rcvmhdr.msg_name = (caddr_t)&rcvfrom; 1598 rcvmhdr.msg_namelen = sizeof(rcvfrom); 1599 rcvmhdr.msg_iov = rcviov; 1600 rcvmhdr.msg_iovlen = 1; 1601 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf; 1602 rcvmhdr.msg_controllen = rcvcmsgbuflen; 1603 1604 /* initialize msghdr for sending packets */ 1605 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6); 1606 sndmhdr.msg_iov = sndiov; 1607 sndmhdr.msg_iovlen = 1; 1608 sndmhdr.msg_control = (caddr_t)sndcmsgbuf; 1609 sndmhdr.msg_controllen = sndcmsgbuflen; 1610 1611 return; 1612} 1613 1614/* open a routing socket to watch the routing table */ 1615static void 1616rtsock_open(struct sockinfo *s) 1617{ 1618 if (s == NULL) { 1619 syslog(LOG_ERR, "<%s> internal error", __func__); 1620 exit(1); 1621 } 1622 if ((s->si_fd = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) { 1623 syslog(LOG_ERR, 1624 "<%s> socket: %s", __func__, strerror(errno)); 1625 exit(1); 1626 } 1627} 1628 1629struct ifinfo * 1630if_indextoifinfo(int idx) 1631{ 1632 struct ifinfo *ifi; 1633 char *name, name0[IFNAMSIZ]; 1634 1635 /* Check if the interface has a valid name or not. */ 1636 if (if_indextoname(idx, name0) == NULL) 1637 return (NULL); 1638 1639 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1640 if (ifi->ifi_ifindex == idx) 1641 return (ifi); 1642 } 1643 1644 if (ifi != NULL) 1645 syslog(LOG_DEBUG, "<%s> ifi found (idx=%d)", 1646 __func__, idx); 1647 else 1648 syslog(LOG_DEBUG, "<%s> ifi not found (idx=%d)", 1649 __func__, idx); 1650 1651 return (NULL); /* search failed */ 1652} 1653 1654void 1655ra_output(struct ifinfo *ifi) 1656{ 1657 int i; 1658 struct cmsghdr *cm; 1659 struct in6_pktinfo *pi; 1660 struct soliciter *sol; 1661 struct rainfo *rai; 1662 1663 switch (ifi->ifi_state) { 1664 case IFI_STATE_CONFIGURED: 1665 rai = ifi->ifi_rainfo; 1666 break; 1667 case IFI_STATE_TRANSITIVE: 1668 rai = ifi->ifi_rainfo_trans; 1669 break; 1670 case IFI_STATE_UNCONFIGURED: 1671 syslog(LOG_DEBUG, "<%s> %s is unconfigured. " 1672 "Skip sending RAs.", 1673 __func__, ifi->ifi_ifname); 1674 return; 1675 default: 1676 rai = NULL; 1677 } 1678 if (rai == NULL) { 1679 syslog(LOG_DEBUG, "<%s> rainfo is NULL on %s." 1680 "Skip sending RAs.", 1681 __func__, ifi->ifi_ifname); 1682 return; 1683 } 1684 if (!(ifi->ifi_flags & IFF_UP)) { 1685 syslog(LOG_DEBUG, "<%s> %s is not up. " 1686 "Skip sending RAs.", 1687 __func__, ifi->ifi_ifname); 1688 return; 1689 } 1690 /* 1691 * Check lifetime, ACCEPT_RTADV flag, and ip6.forwarding. 1692 * 1693 * (lifetime == 0) = output 1694 * (lifetime != 0 && (check_accept_rtadv()) = no output 1695 * 1696 * Basically, hosts MUST NOT send Router Advertisement 1697 * messages at any time (RFC 4861, Section 6.2.3). However, it 1698 * would sometimes be useful to allow hosts to advertise some 1699 * parameters such as prefix information and link MTU. Thus, 1700 * we allow hosts to invoke rtadvd only when router lifetime 1701 * (on every advertising interface) is explicitly set 1702 * zero. (see also the above section) 1703 */ 1704 syslog(LOG_DEBUG, 1705 "<%s> check lifetime=%d, ACCEPT_RTADV=%d, ip6.forwarding=%d " 1706 "on %s", __func__, 1707 rai->rai_lifetime, 1708 check_accept_rtadv(ifi->ifi_ifindex), 1709 getinet6sysctl(IPV6CTL_FORWARDING), 1710 ifi->ifi_ifname); 1711 1712 if (rai->rai_lifetime != 0) { 1713 if (getinet6sysctl(IPV6CTL_FORWARDING) == 0) { 1714 syslog(LOG_ERR, 1715 "non-zero lifetime RA " 1716 "but net.inet6.ip6.forwarding=0. " 1717 "Ignored."); 1718 return; 1719 } 1720 if (check_accept_rtadv(ifi->ifi_ifindex)) { 1721 syslog(LOG_ERR, 1722 "non-zero lifetime RA " 1723 "on RA receiving interface %s." 1724 " Ignored.", ifi->ifi_ifname); 1725 return; 1726 } 1727 } 1728 1729 make_packet(rai); /* XXX: inefficient */ 1730 1731 sndmhdr.msg_name = (caddr_t)&sin6_linklocal_allnodes; 1732 sndmhdr.msg_iov[0].iov_base = (caddr_t)rai->rai_ra_data; 1733 sndmhdr.msg_iov[0].iov_len = rai->rai_ra_datalen; 1734 1735 cm = CMSG_FIRSTHDR(&sndmhdr); 1736 /* specify the outgoing interface */ 1737 cm->cmsg_level = IPPROTO_IPV6; 1738 cm->cmsg_type = IPV6_PKTINFO; 1739 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); 1740 pi = (struct in6_pktinfo *)CMSG_DATA(cm); 1741 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/ 1742 pi->ipi6_ifindex = ifi->ifi_ifindex; 1743 1744 /* specify the hop limit of the packet */ 1745 { 1746 int hoplimit = 255; 1747 1748 cm = CMSG_NXTHDR(&sndmhdr, cm); 1749 cm->cmsg_level = IPPROTO_IPV6; 1750 cm->cmsg_type = IPV6_HOPLIMIT; 1751 cm->cmsg_len = CMSG_LEN(sizeof(int)); 1752 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int)); 1753 } 1754 1755 syslog(LOG_DEBUG, 1756 "<%s> send RA on %s, # of RS waitings = %d", 1757 __func__, ifi->ifi_ifname, ifi->ifi_rs_waitcount); 1758 1759 i = sendmsg(sock.si_fd, &sndmhdr, 0); 1760 1761 if (i < 0 || (size_t)i != rai->rai_ra_datalen) { 1762 if (i < 0) { 1763 syslog(LOG_ERR, "<%s> sendmsg on %s: %s", 1764 __func__, ifi->ifi_ifname, 1765 strerror(errno)); 1766 } 1767 } 1768 1769 /* 1770 * unicast advertisements 1771 * XXX commented out. reason: though spec does not forbit it, unicast 1772 * advert does not really help 1773 */ 1774 while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) { 1775 TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next); 1776 free(sol); 1777 } 1778 1779 /* update timestamp */ 1780 clock_gettime(CLOCK_MONOTONIC_FAST, &ifi->ifi_ra_lastsent); 1781 1782 /* update counter */ 1783 ifi->ifi_rs_waitcount = 0; 1784 ifi->ifi_raoutput++; 1785 1786 switch (ifi->ifi_state) { 1787 case IFI_STATE_CONFIGURED: 1788 if (ifi->ifi_burstcount > 0) 1789 ifi->ifi_burstcount--; 1790 break; 1791 case IFI_STATE_TRANSITIVE: 1792 ifi->ifi_burstcount--; 1793 if (ifi->ifi_burstcount == 0) { 1794 if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) { 1795 /* Initial burst finished. */ 1796 if (ifi->ifi_rainfo_trans != NULL) 1797 ifi->ifi_rainfo_trans = NULL; 1798 } 1799 1800 /* Remove burst RA information */ 1801 if (ifi->ifi_rainfo_trans != NULL) { 1802 rm_rainfo(ifi->ifi_rainfo_trans); 1803 ifi->ifi_rainfo_trans = NULL; 1804 } 1805 1806 if (ifi->ifi_rainfo != NULL) { 1807 /* 1808 * TRANSITIVE -> CONFIGURED 1809 * 1810 * After initial burst or transition from 1811 * one configuration to another, 1812 * ifi_rainfo always points to the next RA 1813 * information. 1814 */ 1815 ifi->ifi_state = IFI_STATE_CONFIGURED; 1816 syslog(LOG_DEBUG, 1817 "<%s> ifname=%s marked as " 1818 "CONFIGURED.", __func__, 1819 ifi->ifi_ifname); 1820 } else { 1821 /* 1822 * TRANSITIVE -> UNCONFIGURED 1823 * 1824 * If ifi_rainfo points to NULL, this 1825 * interface is shutting down. 1826 * 1827 */ 1828 int error; 1829 1830 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 1831 syslog(LOG_DEBUG, 1832 "<%s> ifname=%s marked as " 1833 "UNCONFIGURED.", __func__, 1834 ifi->ifi_ifname); 1835 error = sock_mc_leave(&sock, 1836 ifi->ifi_ifindex); 1837 if (error) 1838 exit(1); 1839 } 1840 } 1841 break; 1842 } 1843} 1844 1845/* process RA timer */ 1846struct rtadvd_timer * 1847ra_timeout(void *arg) 1848{ 1849 struct ifinfo *ifi; 1850 1851 ifi = (struct ifinfo *)arg; 1852 syslog(LOG_DEBUG, "<%s> RA timer on %s is expired", 1853 __func__, ifi->ifi_ifname); 1854 1855 ra_output(ifi); 1856 1857 return (ifi->ifi_ra_timer); 1858} 1859 1860/* update RA timer */ 1861void 1862ra_timer_update(void *arg, struct timespec *tm) 1863{ 1864 uint16_t interval; 1865 struct rainfo *rai; 1866 struct ifinfo *ifi; 1867 1868 ifi = (struct ifinfo *)arg; 1869 rai = ifi->ifi_rainfo; 1870 interval = 0; 1871 1872 switch (ifi->ifi_state) { 1873 case IFI_STATE_UNCONFIGURED: 1874 return; 1875 break; 1876 case IFI_STATE_CONFIGURED: 1877 /* 1878 * Whenever a multicast advertisement is sent from 1879 * an interface, the timer is reset to a 1880 * uniformly-distributed random value between the 1881 * interface's configured MinRtrAdvInterval and 1882 * MaxRtrAdvInterval (RFC4861 6.2.4). 1883 */ 1884 interval = rai->rai_mininterval; 1885 interval += arc4random_uniform(rai->rai_maxinterval - 1886 rai->rai_mininterval); 1887 break; 1888 case IFI_STATE_TRANSITIVE: 1889 /* 1890 * For the first few advertisements (up to 1891 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen 1892 * interval is greater than 1893 * MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer SHOULD be 1894 * set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. (RFC 1895 * 4861 6.2.4) 1896 * 1897 * In such cases, the router SHOULD transmit one or more 1898 * (but not more than MAX_FINAL_RTR_ADVERTISEMENTS) final 1899 * multicast Router Advertisements on the interface with a 1900 * Router Lifetime field of zero. (RFC 4861 6.2.5) 1901 */ 1902 interval = ifi->ifi_burstinterval; 1903 break; 1904 } 1905 1906 tm->tv_sec = interval; 1907 tm->tv_nsec = 0; 1908 1909 syslog(LOG_DEBUG, 1910 "<%s> RA timer on %s is set to %ld:%ld", 1911 __func__, ifi->ifi_ifname, 1912 (long int)tm->tv_sec, (long int)tm->tv_nsec / 1000); 1913 1914 return; 1915} 1916