1 /* $FreeBSD: stable/10/usr.sbin/rtadvd/rtadvd.c 275038 2014-11-25 13:12:45Z dim $ */ 2 /* $KAME: rtadvd.c,v 1.82 2003/08/05 12:34:23 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/param.h> 35 #include <sys/ioctl.h> 36 #include <sys/socket.h> 37 #include <sys/uio.h> 38 #include <sys/queue.h> 39 #include <sys/stat.h> 40 #include <sys/sysctl.h> 41 42 #include <net/if.h> 43 #include <net/if_types.h> 44 #include <net/if_media.h> 45 #include <net/if_dl.h> 46 #include <net/route.h> 47 #include <netinet/in.h> 48 #include <netinet/ip6.h> 49 #include <netinet6/ip6_var.h> 50 #include <netinet/icmp6.h> 51 52 #include <arpa/inet.h> 53 54 #include <net/if_var.h> 55 #include <netinet/in_var.h> 56 #include <netinet6/nd6.h> 57 58 #include <time.h> 59 #include <unistd.h> 60 #include <stdio.h> 61 #include <err.h> 62 #include <errno.h> 63 #include <inttypes.h> 64 #include <libutil.h> 65 #include <netdb.h> 66 #include <signal.h> 67 #include <string.h> 68 #include <stdlib.h> 69 #include <syslog.h> 70 #include <poll.h> 71 72 #include "pathnames.h" 73 #include "rtadvd.h" 74 #include "if.h" 75 #include "rrenum.h" 76 #include "advcap.h" 77 #include "timer_subr.h" 78 #include "timer.h" 79 #include "config.h" 80 #include "control.h" 81 #include "control_server.h" 82 83 #define RTADV_TYPE2BITMASK(type) (0x1 << type) 84 85 struct msghdr rcvmhdr; 86 static char *rcvcmsgbuf; 87 static size_t rcvcmsgbuflen; 88 static char *sndcmsgbuf = NULL; 89 static size_t sndcmsgbuflen; 90 struct msghdr sndmhdr; 91 struct iovec rcviov[2]; 92 struct iovec sndiov[2]; 93 struct sockaddr_in6 rcvfrom; 94 static const char *pidfilename = _PATH_RTADVDPID; 95 const char *conffile = _PATH_RTADVDCONF; 96 static struct pidfh *pfh; 97 static int dflag, sflag; 98 static int wait_shutdown; 99 100 #define PFD_RAWSOCK 0 101 #define PFD_RTSOCK 1 102 #define PFD_CSOCK 2 103 #define PFD_MAX 3 104 105 struct railist_head_t railist = 106 TAILQ_HEAD_INITIALIZER(railist); 107 struct ifilist_head_t ifilist = 108 TAILQ_HEAD_INITIALIZER(ifilist); 109 110 struct nd_optlist { 111 TAILQ_ENTRY(nd_optlist) nol_next; 112 struct nd_opt_hdr *nol_opt; 113 }; 114 union nd_opt { 115 struct nd_opt_hdr *opt_array[9]; 116 struct { 117 struct nd_opt_hdr *zero; 118 struct nd_opt_hdr *src_lladdr; 119 struct nd_opt_hdr *tgt_lladdr; 120 struct nd_opt_prefix_info *pi; 121 struct nd_opt_rd_hdr *rh; 122 struct nd_opt_mtu *mtu; 123 TAILQ_HEAD(, nd_optlist) opt_list; 124 } nd_opt_each; 125 }; 126 #define opt_src_lladdr nd_opt_each.src_lladdr 127 #define opt_tgt_lladdr nd_opt_each.tgt_lladdr 128 #define opt_pi nd_opt_each.pi 129 #define opt_rh nd_opt_each.rh 130 #define opt_mtu nd_opt_each.mtu 131 #define opt_list nd_opt_each.opt_list 132 133 #define NDOPT_FLAG_SRCLINKADDR (1 << 0) 134 #define NDOPT_FLAG_TGTLINKADDR (1 << 1) 135 #define NDOPT_FLAG_PREFIXINFO (1 << 2) 136 #define NDOPT_FLAG_RDHDR (1 << 3) 137 #define NDOPT_FLAG_MTU (1 << 4) 138 #define NDOPT_FLAG_RDNSS (1 << 5) 139 #define NDOPT_FLAG_DNSSL (1 << 6) 140 141 static uint32_t ndopt_flags[] = { 142 [ND_OPT_SOURCE_LINKADDR] = NDOPT_FLAG_SRCLINKADDR, 143 [ND_OPT_TARGET_LINKADDR] = NDOPT_FLAG_TGTLINKADDR, 144 [ND_OPT_PREFIX_INFORMATION] = NDOPT_FLAG_PREFIXINFO, 145 [ND_OPT_REDIRECTED_HEADER] = NDOPT_FLAG_RDHDR, 146 [ND_OPT_MTU] = NDOPT_FLAG_MTU, 147 [ND_OPT_RDNSS] = NDOPT_FLAG_RDNSS, 148 [ND_OPT_DNSSL] = NDOPT_FLAG_DNSSL, 149 }; 150 151 static void rtadvd_shutdown(void); 152 static void sock_open(struct sockinfo *); 153 static void rtsock_open(struct sockinfo *); 154 static void rtadvd_input(struct sockinfo *); 155 static void rs_input(int, struct nd_router_solicit *, 156 struct in6_pktinfo *, struct sockaddr_in6 *); 157 static void ra_input(int, struct nd_router_advert *, 158 struct in6_pktinfo *, struct sockaddr_in6 *); 159 static int prefix_check(struct nd_opt_prefix_info *, struct rainfo *, 160 struct sockaddr_in6 *); 161 static int nd6_options(struct nd_opt_hdr *, int, 162 union nd_opt *, uint32_t); 163 static void free_ndopts(union nd_opt *); 164 static void rtmsg_input(struct sockinfo *); 165 static void set_short_delay(struct ifinfo *); 166 static int check_accept_rtadv(int); 167 168 static void 169 usage(void) 170 { 171 172 fprintf(stderr, "usage: rtadvd [-dDfRs] " 173 "[-c configfile] [-C ctlsock] [-M ifname] [-p pidfile]\n"); 174 exit(1); 175 } 176 177 int 178 main(int argc, char *argv[]) 179 { 180 struct pollfd set[PFD_MAX]; 181 struct timespec *timeout; 182 int i, ch; 183 int fflag = 0, logopt; 184 int error; 185 pid_t otherpid; 186 187 /* get command line options and arguments */ 188 while ((ch = getopt(argc, argv, "c:C:dDfhM:p:Rs")) != -1) { 189 switch (ch) { 190 case 'c': 191 conffile = optarg; 192 break; 193 case 'C': 194 ctrlsock.si_name = optarg; 195 break; 196 case 'd': 197 dflag++; 198 break; 199 case 'D': 200 dflag += 3; 201 break; 202 case 'f': 203 fflag = 1; 204 break; 205 case 'M': 206 mcastif = optarg; 207 break; 208 case 'R': 209 fprintf(stderr, "rtadvd: " 210 "the -R option is currently ignored.\n"); 211 /* accept_rr = 1; */ 212 /* run anyway... */ 213 break; 214 case 's': 215 sflag = 1; 216 break; 217 case 'p': 218 pidfilename = optarg; 219 break; 220 default: 221 usage(); 222 } 223 } 224 argc -= optind; 225 argv += optind; 226 227 logopt = LOG_NDELAY | LOG_PID; 228 if (fflag) 229 logopt |= LOG_PERROR; 230 openlog("rtadvd", logopt, LOG_DAEMON); 231 232 /* set log level */ 233 if (dflag > 2) 234 (void)setlogmask(LOG_UPTO(LOG_DEBUG)); 235 else if (dflag > 1) 236 (void)setlogmask(LOG_UPTO(LOG_INFO)); 237 else if (dflag > 0) 238 (void)setlogmask(LOG_UPTO(LOG_NOTICE)); 239 else 240 (void)setlogmask(LOG_UPTO(LOG_ERR)); 241 242 /* timer initialization */ 243 rtadvd_timer_init(); 244 245 #ifndef HAVE_ARC4RANDOM 246 /* random value initialization */ 247 #ifdef __FreeBSD__ 248 srandomdev(); 249 #else 250 srandom((unsigned long)time(NULL)); 251 #endif 252 #endif 253 pfh = pidfile_open(pidfilename, 0600, &otherpid); 254 if (pfh == NULL) { 255 if (errno == EEXIST) 256 errx(1, "%s already running, pid: %d", 257 getprogname(), otherpid); 258 syslog(LOG_ERR, 259 "failed to open the pid file %s, run anyway.", 260 pidfilename); 261 } 262 if (!fflag) 263 daemon(1, 0); 264 265 sock_open(&sock); 266 267 update_ifinfo(&ifilist, UPDATE_IFINFO_ALL); 268 for (i = 0; i < argc; i++) 269 update_persist_ifinfo(&ifilist, argv[i]); 270 271 csock_open(&ctrlsock, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH); 272 if (ctrlsock.si_fd == -1) { 273 syslog(LOG_ERR, "cannot open control socket: %s", 274 strerror(errno)); 275 exit(1); 276 } 277 278 /* record the current PID */ 279 pidfile_write(pfh); 280 281 set[PFD_RAWSOCK].fd = sock.si_fd; 282 set[PFD_RAWSOCK].events = POLLIN; 283 if (sflag == 0) { 284 rtsock_open(&rtsock); 285 set[PFD_RTSOCK].fd = rtsock.si_fd; 286 set[PFD_RTSOCK].events = POLLIN; 287 } else 288 set[PFD_RTSOCK].fd = -1; 289 set[PFD_CSOCK].fd = ctrlsock.si_fd; 290 set[PFD_CSOCK].events = POLLIN; 291 signal(SIGTERM, set_do_shutdown); 292 signal(SIGINT, set_do_shutdown); 293 signal(SIGHUP, set_do_reload); 294 295 error = csock_listen(&ctrlsock); 296 if (error) { 297 syslog(LOG_ERR, "cannot listen control socket: %s", 298 strerror(errno)); 299 exit(1); 300 } 301 302 /* load configuration file */ 303 set_do_reload(0); 304 305 while (1) { 306 if (is_do_shutdown()) 307 rtadvd_shutdown(); 308 309 if (is_do_reload()) { 310 loadconfig_ifname(reload_ifname()); 311 if (reload_ifname() == NULL) 312 syslog(LOG_INFO, 313 "configuration file reloaded."); 314 else 315 syslog(LOG_INFO, 316 "configuration file for %s reloaded.", 317 reload_ifname()); 318 reset_do_reload(); 319 } 320 321 /* timeout handler update for active interfaces */ 322 rtadvd_update_timeout_handler(); 323 324 /* timer expiration check and reset the timer */ 325 timeout = rtadvd_check_timer(); 326 327 if (timeout != NULL) { 328 syslog(LOG_DEBUG, 329 "<%s> set timer to %ld:%ld. waiting for " 330 "inputs or timeout", __func__, 331 (long int)timeout->tv_sec, 332 (long int)timeout->tv_nsec / 1000); 333 } else { 334 syslog(LOG_DEBUG, 335 "<%s> there's no timer. waiting for inputs", 336 __func__); 337 } 338 if ((i = poll(set, sizeof(set)/sizeof(set[0]), 339 timeout ? (timeout->tv_sec * 1000 + 340 timeout->tv_nsec / 1000 / 1000) : INFTIM)) < 0) { 341 342 /* EINTR would occur if a signal was delivered */ 343 if (errno != EINTR) 344 syslog(LOG_ERR, "poll() failed: %s", 345 strerror(errno)); 346 continue; 347 } 348 if (i == 0) /* timeout */ 349 continue; 350 if (rtsock.si_fd != -1 && set[PFD_RTSOCK].revents & POLLIN) 351 rtmsg_input(&rtsock); 352 353 if (set[PFD_RAWSOCK].revents & POLLIN) 354 rtadvd_input(&sock); 355 356 if (set[PFD_CSOCK].revents & POLLIN) { 357 int fd; 358 359 fd = csock_accept(&ctrlsock); 360 if (fd == -1) 361 syslog(LOG_ERR, 362 "cannot accept() control socket: %s", 363 strerror(errno)); 364 else { 365 cm_handler_server(fd); 366 close(fd); 367 } 368 } 369 } 370 exit(0); /* NOTREACHED */ 371 } 372 373 static void 374 rtadvd_shutdown(void) 375 { 376 struct ifinfo *ifi; 377 struct rainfo *rai; 378 struct rdnss *rdn; 379 struct dnssl *dns; 380 381 if (wait_shutdown) { 382 syslog(LOG_INFO, 383 "waiting expiration of the all RA timers."); 384 385 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 386 /* 387 * Ignore !IFF_UP interfaces in waiting for shutdown. 388 */ 389 if (!(ifi->ifi_flags & IFF_UP) && 390 ifi->ifi_ra_timer != NULL) { 391 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 392 rtadvd_remove_timer(ifi->ifi_ra_timer); 393 ifi->ifi_ra_timer = NULL; 394 syslog(LOG_DEBUG, "<%s> %s(idx=%d) is down. " 395 "Timer removed and marked as UNCONFIGURED.", 396 __func__, ifi->ifi_ifname, 397 ifi->ifi_ifindex); 398 } 399 } 400 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 401 if (ifi->ifi_ra_timer != NULL) 402 break; 403 } 404 if (ifi == NULL) { 405 syslog(LOG_NOTICE, "gracefully terminated."); 406 exit(0); 407 } 408 409 sleep(1); 410 return; 411 } 412 413 syslog(LOG_DEBUG, "<%s> cease to be an advertising router", 414 __func__); 415 416 wait_shutdown = 1; 417 418 TAILQ_FOREACH(rai, &railist, rai_next) { 419 rai->rai_lifetime = 0; 420 TAILQ_FOREACH(rdn, &rai->rai_rdnss, rd_next) 421 rdn->rd_ltime = 0; 422 TAILQ_FOREACH(dns, &rai->rai_dnssl, dn_next) 423 dns->dn_ltime = 0; 424 } 425 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 426 if (!ifi->ifi_persist) 427 continue; 428 if (ifi->ifi_state == IFI_STATE_UNCONFIGURED) 429 continue; 430 if (ifi->ifi_ra_timer == NULL) 431 continue; 432 if (ifi->ifi_ra_lastsent.tv_sec == 0 && 433 ifi->ifi_ra_lastsent.tv_nsec == 0 && 434 ifi->ifi_ra_timer != NULL) { 435 /* 436 * When RA configured but never sent, 437 * ignore the IF immediately. 438 */ 439 rtadvd_remove_timer(ifi->ifi_ra_timer); 440 ifi->ifi_ra_timer = NULL; 441 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 442 continue; 443 } 444 445 ifi->ifi_state = IFI_STATE_TRANSITIVE; 446 447 /* Mark as the shut-down state. */ 448 ifi->ifi_rainfo_trans = ifi->ifi_rainfo; 449 ifi->ifi_rainfo = NULL; 450 451 ifi->ifi_burstcount = MAX_FINAL_RTR_ADVERTISEMENTS; 452 ifi->ifi_burstinterval = MIN_DELAY_BETWEEN_RAS; 453 454 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm); 455 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm, 456 ifi->ifi_ra_timer); 457 } 458 syslog(LOG_NOTICE, "final RA transmission started."); 459 460 pidfile_remove(pfh); 461 csock_close(&ctrlsock); 462 } 463 464 static void 465 rtmsg_input(struct sockinfo *s) 466 { 467 int n, type, ifindex = 0, plen; 468 size_t len; 469 char msg[2048], *next, *lim; 470 char ifname[IFNAMSIZ]; 471 struct if_announcemsghdr *ifan; 472 struct rt_msghdr *rtm; 473 struct prefix *pfx; 474 struct rainfo *rai; 475 struct in6_addr *addr; 476 struct ifinfo *ifi; 477 char addrbuf[INET6_ADDRSTRLEN]; 478 int prefixchange = 0; 479 480 if (s == NULL) { 481 syslog(LOG_ERR, "<%s> internal error", __func__); 482 exit(1); 483 } 484 n = read(s->si_fd, msg, sizeof(msg)); 485 rtm = (struct rt_msghdr *)msg; 486 syslog(LOG_DEBUG, "<%s> received a routing message " 487 "(type = %d, len = %d)", __func__, rtm->rtm_type, n); 488 489 if (n > rtm->rtm_msglen) { 490 /* 491 * This usually won't happen for messages received on 492 * a routing socket. 493 */ 494 syslog(LOG_DEBUG, 495 "<%s> received data length is larger than " 496 "1st routing message len. multiple messages? " 497 "read %d bytes, but 1st msg len = %d", 498 __func__, n, rtm->rtm_msglen); 499 #if 0 500 /* adjust length */ 501 n = rtm->rtm_msglen; 502 #endif 503 } 504 505 lim = msg + n; 506 for (next = msg; next < lim; next += len) { 507 int oldifflags; 508 509 next = get_next_msg(next, lim, 0, &len, 510 RTADV_TYPE2BITMASK(RTM_ADD) | 511 RTADV_TYPE2BITMASK(RTM_DELETE) | 512 RTADV_TYPE2BITMASK(RTM_NEWADDR) | 513 RTADV_TYPE2BITMASK(RTM_DELADDR) | 514 RTADV_TYPE2BITMASK(RTM_IFINFO) | 515 RTADV_TYPE2BITMASK(RTM_IFANNOUNCE)); 516 if (len == 0) 517 break; 518 type = ((struct rt_msghdr *)next)->rtm_type; 519 switch (type) { 520 case RTM_ADD: 521 case RTM_DELETE: 522 ifindex = get_rtm_ifindex(next); 523 break; 524 case RTM_NEWADDR: 525 case RTM_DELADDR: 526 ifindex = (int)((struct ifa_msghdr *)next)->ifam_index; 527 break; 528 case RTM_IFINFO: 529 ifindex = (int)((struct if_msghdr *)next)->ifm_index; 530 break; 531 case RTM_IFANNOUNCE: 532 ifan = (struct if_announcemsghdr *)next; 533 switch (ifan->ifan_what) { 534 case IFAN_ARRIVAL: 535 case IFAN_DEPARTURE: 536 break; 537 default: 538 syslog(LOG_DEBUG, 539 "<%s:%d> unknown ifan msg (ifan_what=%d)", 540 __func__, __LINE__, ifan->ifan_what); 541 continue; 542 } 543 544 syslog(LOG_DEBUG, "<%s>: if_announcemsg (idx=%d:%d)", 545 __func__, ifan->ifan_index, ifan->ifan_what); 546 switch (ifan->ifan_what) { 547 case IFAN_ARRIVAL: 548 syslog(LOG_NOTICE, 549 "interface added (idx=%d)", 550 ifan->ifan_index); 551 update_ifinfo(&ifilist, ifan->ifan_index); 552 loadconfig_index(ifan->ifan_index); 553 break; 554 case IFAN_DEPARTURE: 555 syslog(LOG_NOTICE, 556 "interface removed (idx=%d)", 557 ifan->ifan_index); 558 rm_ifinfo_index(ifan->ifan_index); 559 560 /* Clear ifi_ifindex */ 561 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 562 if (ifi->ifi_ifindex 563 == ifan->ifan_index) { 564 ifi->ifi_ifindex = 0; 565 break; 566 } 567 } 568 update_ifinfo(&ifilist, ifan->ifan_index); 569 break; 570 } 571 continue; 572 default: 573 /* should not reach here */ 574 syslog(LOG_DEBUG, 575 "<%s:%d> unknown rtmsg %d on %s", 576 __func__, __LINE__, type, 577 if_indextoname(ifindex, ifname)); 578 continue; 579 } 580 ifi = if_indextoifinfo(ifindex); 581 if (ifi == NULL) { 582 syslog(LOG_DEBUG, 583 "<%s> ifinfo not found for idx=%d. Why?", 584 __func__, ifindex); 585 continue; 586 } 587 rai = ifi->ifi_rainfo; 588 if (rai == NULL) { 589 syslog(LOG_DEBUG, 590 "<%s> route changed on " 591 "non advertising interface(%s)", 592 __func__, ifi->ifi_ifname); 593 continue; 594 } 595 596 oldifflags = ifi->ifi_flags; 597 /* init ifflags because it may have changed */ 598 update_ifinfo(&ifilist, ifindex); 599 600 switch (type) { 601 case RTM_ADD: 602 if (sflag) 603 break; /* we aren't interested in prefixes */ 604 605 addr = get_addr(msg); 606 plen = get_prefixlen(msg); 607 /* sanity check for plen */ 608 /* as RFC2373, prefixlen is at least 4 */ 609 if (plen < 4 || plen > 127) { 610 syslog(LOG_INFO, "<%s> new interface route's" 611 "plen %d is invalid for a prefix", 612 __func__, plen); 613 break; 614 } 615 pfx = find_prefix(rai, addr, plen); 616 if (pfx) { 617 if (pfx->pfx_timer) { 618 /* 619 * If the prefix has been invalidated, 620 * make it available again. 621 */ 622 update_prefix(pfx); 623 prefixchange = 1; 624 } else 625 syslog(LOG_DEBUG, 626 "<%s> new prefix(%s/%d) " 627 "added on %s, " 628 "but it was already in list", 629 __func__, 630 inet_ntop(AF_INET6, addr, 631 (char *)addrbuf, 632 sizeof(addrbuf)), 633 plen, ifi->ifi_ifname); 634 break; 635 } 636 make_prefix(rai, ifindex, addr, plen); 637 prefixchange = 1; 638 break; 639 case RTM_DELETE: 640 if (sflag) 641 break; 642 643 addr = get_addr(msg); 644 plen = get_prefixlen(msg); 645 /* sanity check for plen */ 646 /* as RFC2373, prefixlen is at least 4 */ 647 if (plen < 4 || plen > 127) { 648 syslog(LOG_INFO, 649 "<%s> deleted interface route's " 650 "plen %d is invalid for a prefix", 651 __func__, plen); 652 break; 653 } 654 pfx = find_prefix(rai, addr, plen); 655 if (pfx == NULL) { 656 syslog(LOG_DEBUG, 657 "<%s> prefix(%s/%d) was deleted on %s, " 658 "but it was not in list", 659 __func__, inet_ntop(AF_INET6, addr, 660 (char *)addrbuf, sizeof(addrbuf)), 661 plen, ifi->ifi_ifname); 662 break; 663 } 664 invalidate_prefix(pfx); 665 prefixchange = 1; 666 break; 667 case RTM_NEWADDR: 668 case RTM_DELADDR: 669 case RTM_IFINFO: 670 break; 671 default: 672 /* should not reach here */ 673 syslog(LOG_DEBUG, 674 "<%s:%d> unknown rtmsg %d on %s", 675 __func__, __LINE__, type, 676 if_indextoname(ifindex, ifname)); 677 return; 678 } 679 680 /* check if an interface flag is changed */ 681 if ((oldifflags & IFF_UP) && /* UP to DOWN */ 682 !(ifi->ifi_flags & IFF_UP)) { 683 syslog(LOG_NOTICE, 684 "<interface %s becomes down. stop timer.", 685 ifi->ifi_ifname); 686 rtadvd_remove_timer(ifi->ifi_ra_timer); 687 ifi->ifi_ra_timer = NULL; 688 } else if (!(oldifflags & IFF_UP) && /* DOWN to UP */ 689 (ifi->ifi_flags & IFF_UP)) { 690 syslog(LOG_NOTICE, 691 "interface %s becomes up. restart timer.", 692 ifi->ifi_ifname); 693 694 ifi->ifi_state = IFI_STATE_TRANSITIVE; 695 ifi->ifi_burstcount = 696 MAX_INITIAL_RTR_ADVERTISEMENTS; 697 ifi->ifi_burstinterval = 698 MAX_INITIAL_RTR_ADVERT_INTERVAL; 699 700 ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout, 701 ra_timer_update, ifi, ifi); 702 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm); 703 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm, 704 ifi->ifi_ra_timer); 705 } else if (prefixchange && 706 (ifi->ifi_flags & IFF_UP)) { 707 /* 708 * An advertised prefix has been added or invalidated. 709 * Will notice the change in a short delay. 710 */ 711 set_short_delay(ifi); 712 } 713 } 714 715 return; 716 } 717 718 void 719 rtadvd_input(struct sockinfo *s) 720 { 721 ssize_t i; 722 int *hlimp = NULL; 723 #ifdef OLDRAWSOCKET 724 struct ip6_hdr *ip; 725 #endif 726 struct icmp6_hdr *icp; 727 int ifindex = 0; 728 struct cmsghdr *cm; 729 struct in6_pktinfo *pi = NULL; 730 char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; 731 struct in6_addr dst = in6addr_any; 732 struct ifinfo *ifi; 733 734 syslog(LOG_DEBUG, "<%s> enter", __func__); 735 736 if (s == NULL) { 737 syslog(LOG_ERR, "<%s> internal error", __func__); 738 exit(1); 739 } 740 /* 741 * Get message. We reset msg_controllen since the field could 742 * be modified if we had received a message before setting 743 * receive options. 744 */ 745 rcvmhdr.msg_controllen = rcvcmsgbuflen; 746 if ((i = recvmsg(s->si_fd, &rcvmhdr, 0)) < 0) 747 return; 748 749 /* extract optional information via Advanced API */ 750 for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr); 751 cm; 752 cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) { 753 if (cm->cmsg_level == IPPROTO_IPV6 && 754 cm->cmsg_type == IPV6_PKTINFO && 755 cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) { 756 pi = (struct in6_pktinfo *)(CMSG_DATA(cm)); 757 ifindex = pi->ipi6_ifindex; 758 dst = pi->ipi6_addr; 759 } 760 if (cm->cmsg_level == IPPROTO_IPV6 && 761 cm->cmsg_type == IPV6_HOPLIMIT && 762 cm->cmsg_len == CMSG_LEN(sizeof(int))) 763 hlimp = (int *)CMSG_DATA(cm); 764 } 765 if (ifindex == 0) { 766 syslog(LOG_ERR, "failed to get receiving interface"); 767 return; 768 } 769 if (hlimp == NULL) { 770 syslog(LOG_ERR, "failed to get receiving hop limit"); 771 return; 772 } 773 774 /* 775 * If we happen to receive data on an interface which is now gone 776 * or down, just discard the data. 777 */ 778 ifi = if_indextoifinfo(pi->ipi6_ifindex); 779 if (ifi == NULL || !(ifi->ifi_flags & IFF_UP)) { 780 syslog(LOG_INFO, 781 "<%s> received data on a disabled interface (%s)", 782 __func__, 783 (ifi == NULL) ? "[gone]" : ifi->ifi_ifname); 784 return; 785 } 786 787 #ifdef OLDRAWSOCKET 788 if ((size_t)i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) { 789 syslog(LOG_ERR, 790 "packet size(%d) is too short", i); 791 return; 792 } 793 794 ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base; 795 icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */ 796 #else 797 if ((size_t)i < sizeof(struct icmp6_hdr)) { 798 syslog(LOG_ERR, "packet size(%zd) is too short", i); 799 return; 800 } 801 802 icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base; 803 #endif 804 805 switch (icp->icmp6_type) { 806 case ND_ROUTER_SOLICIT: 807 /* 808 * Message verification - RFC 4861 6.1.1 809 * XXX: these checks must be done in the kernel as well, 810 * but we can't completely rely on them. 811 */ 812 if (*hlimp != 255) { 813 syslog(LOG_NOTICE, 814 "RS with invalid hop limit(%d) " 815 "received from %s on %s", 816 *hlimp, 817 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 818 sizeof(ntopbuf)), 819 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 820 return; 821 } 822 if (icp->icmp6_code) { 823 syslog(LOG_NOTICE, 824 "RS with invalid ICMP6 code(%d) " 825 "received from %s on %s", 826 icp->icmp6_code, 827 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 828 sizeof(ntopbuf)), 829 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 830 return; 831 } 832 if ((size_t)i < sizeof(struct nd_router_solicit)) { 833 syslog(LOG_NOTICE, 834 "RS from %s on %s does not have enough " 835 "length (len = %zd)", 836 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 837 sizeof(ntopbuf)), 838 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 839 return; 840 } 841 rs_input(i, (struct nd_router_solicit *)icp, pi, &rcvfrom); 842 break; 843 case ND_ROUTER_ADVERT: 844 /* 845 * Message verification - RFC 4861 6.1.2 846 * XXX: there's the same dilemma as above... 847 */ 848 if (!IN6_IS_ADDR_LINKLOCAL(&rcvfrom.sin6_addr)) { 849 syslog(LOG_NOTICE, 850 "RA with non-linklocal source address " 851 "received from %s on %s", 852 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, 853 ntopbuf, sizeof(ntopbuf)), 854 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 855 return; 856 } 857 if (*hlimp != 255) { 858 syslog(LOG_NOTICE, 859 "RA with invalid hop limit(%d) " 860 "received from %s on %s", 861 *hlimp, 862 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 863 sizeof(ntopbuf)), 864 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 865 return; 866 } 867 if (icp->icmp6_code) { 868 syslog(LOG_NOTICE, 869 "RA with invalid ICMP6 code(%d) " 870 "received from %s on %s", 871 icp->icmp6_code, 872 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 873 sizeof(ntopbuf)), 874 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 875 return; 876 } 877 if ((size_t)i < sizeof(struct nd_router_advert)) { 878 syslog(LOG_NOTICE, 879 "RA from %s on %s does not have enough " 880 "length (len = %zd)", 881 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 882 sizeof(ntopbuf)), 883 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 884 return; 885 } 886 ra_input(i, (struct nd_router_advert *)icp, pi, &rcvfrom); 887 break; 888 case ICMP6_ROUTER_RENUMBERING: 889 if (mcastif == NULL) { 890 syslog(LOG_ERR, "received a router renumbering " 891 "message, but not allowed to be accepted"); 892 break; 893 } 894 rr_input(i, (struct icmp6_router_renum *)icp, pi, &rcvfrom, 895 &dst); 896 break; 897 default: 898 /* 899 * Note that this case is POSSIBLE, especially just 900 * after invocation of the daemon. This is because we 901 * could receive message after opening the socket and 902 * before setting ICMP6 type filter(see sock_open()). 903 */ 904 syslog(LOG_ERR, "invalid icmp type(%d)", icp->icmp6_type); 905 return; 906 } 907 908 return; 909 } 910 911 static void 912 rs_input(int len, struct nd_router_solicit *rs, 913 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 914 { 915 char ntopbuf[INET6_ADDRSTRLEN]; 916 char ifnamebuf[IFNAMSIZ]; 917 union nd_opt ndopts; 918 struct rainfo *rai; 919 struct ifinfo *ifi; 920 struct soliciter *sol; 921 922 syslog(LOG_DEBUG, 923 "<%s> RS received from %s on %s", 924 __func__, 925 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 926 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 927 928 /* ND option check */ 929 memset(&ndopts, 0, sizeof(ndopts)); 930 TAILQ_INIT(&ndopts.opt_list); 931 if (nd6_options((struct nd_opt_hdr *)(rs + 1), 932 len - sizeof(struct nd_router_solicit), 933 &ndopts, NDOPT_FLAG_SRCLINKADDR)) { 934 syslog(LOG_INFO, 935 "<%s> ND option check failed for an RS from %s on %s", 936 __func__, 937 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 938 sizeof(ntopbuf)), 939 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 940 return; 941 } 942 943 /* 944 * If the IP source address is the unspecified address, there 945 * must be no source link-layer address option in the message. 946 * (RFC 4861 6.1.1) 947 */ 948 if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) && 949 ndopts.opt_src_lladdr) { 950 syslog(LOG_INFO, 951 "<%s> RS from unspecified src on %s has a link-layer" 952 " address option", 953 __func__, if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 954 goto done; 955 } 956 957 ifi = if_indextoifinfo(pi->ipi6_ifindex); 958 if (ifi == NULL) { 959 syslog(LOG_INFO, 960 "<%s> if (idx=%d) not found. Why?", 961 __func__, pi->ipi6_ifindex); 962 goto done; 963 } 964 rai = ifi->ifi_rainfo; 965 if (rai == NULL) { 966 syslog(LOG_INFO, 967 "<%s> RS received on non advertising interface(%s)", 968 __func__, 969 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 970 goto done; 971 } 972 973 rai->rai_ifinfo->ifi_rsinput++; 974 975 /* 976 * Decide whether to send RA according to the rate-limit 977 * consideration. 978 */ 979 980 /* record sockaddr waiting for RA, if possible */ 981 sol = (struct soliciter *)malloc(sizeof(*sol)); 982 if (sol) { 983 sol->sol_addr = *from; 984 /* XXX RFC 2553 need clarification on flowinfo */ 985 sol->sol_addr.sin6_flowinfo = 0; 986 TAILQ_INSERT_TAIL(&rai->rai_soliciter, sol, sol_next); 987 } 988 989 /* 990 * If there is already a waiting RS packet, don't 991 * update the timer. 992 */ 993 if (ifi->ifi_rs_waitcount++) 994 goto done; 995 996 set_short_delay(ifi); 997 998 done: 999 free_ndopts(&ndopts); 1000 return; 1001 } 1002 1003 static void 1004 set_short_delay(struct ifinfo *ifi) 1005 { 1006 long delay; /* must not be greater than 1000000 */ 1007 struct timespec interval, now, min_delay, tm_tmp, *rest; 1008 1009 if (ifi->ifi_ra_timer == NULL) 1010 return; 1011 /* 1012 * Compute a random delay. If the computed value 1013 * corresponds to a time later than the time the next 1014 * multicast RA is scheduled to be sent, ignore the random 1015 * delay and send the advertisement at the 1016 * already-scheduled time. RFC 4861 6.2.6 1017 */ 1018 #ifdef HAVE_ARC4RANDOM 1019 delay = arc4random_uniform(MAX_RA_DELAY_TIME); 1020 #else 1021 delay = random() % MAX_RA_DELAY_TIME; 1022 #endif 1023 interval.tv_sec = 0; 1024 interval.tv_nsec = delay * 1000; 1025 rest = rtadvd_timer_rest(ifi->ifi_ra_timer); 1026 if (TS_CMP(rest, &interval, <)) { 1027 syslog(LOG_DEBUG, "<%s> random delay is larger than " 1028 "the rest of the current timer", __func__); 1029 interval = *rest; 1030 } 1031 1032 /* 1033 * If we sent a multicast Router Advertisement within 1034 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule 1035 * the advertisement to be sent at a time corresponding to 1036 * MIN_DELAY_BETWEEN_RAS plus the random value after the 1037 * previous advertisement was sent. 1038 */ 1039 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1040 TS_SUB(&now, &ifi->ifi_ra_lastsent, &tm_tmp); 1041 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS; 1042 min_delay.tv_nsec = 0; 1043 if (TS_CMP(&tm_tmp, &min_delay, <)) { 1044 TS_SUB(&min_delay, &tm_tmp, &min_delay); 1045 TS_ADD(&min_delay, &interval, &interval); 1046 } 1047 rtadvd_set_timer(&interval, ifi->ifi_ra_timer); 1048 } 1049 1050 static int 1051 check_accept_rtadv(int idx) 1052 { 1053 struct ifinfo *ifi; 1054 1055 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1056 if (ifi->ifi_ifindex == idx) 1057 break; 1058 } 1059 if (ifi == NULL) { 1060 syslog(LOG_DEBUG, 1061 "<%s> if (idx=%d) not found. Why?", 1062 __func__, idx); 1063 return (0); 1064 } 1065 #if (__FreeBSD_version < 900000) 1066 /* 1067 * RA_RECV: !ip6.forwarding && ip6.accept_rtadv 1068 * RA_SEND: ip6.forwarding 1069 */ 1070 return ((getinet6sysctl(IPV6CTL_FORWARDING) == 0) && 1071 (getinet6sysctl(IPV6CTL_ACCEPT_RTADV) == 1)); 1072 #else 1073 /* 1074 * RA_RECV: ND6_IFF_ACCEPT_RTADV 1075 * RA_SEND: ip6.forwarding 1076 */ 1077 if (update_ifinfo_nd_flags(ifi) != 0) { 1078 syslog(LOG_ERR, "cannot get nd6 flags (idx=%d)", idx); 1079 return (0); 1080 } 1081 1082 return (ifi->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV); 1083 #endif 1084 } 1085 1086 static void 1087 ra_input(int len, struct nd_router_advert *nra, 1088 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 1089 { 1090 struct rainfo *rai; 1091 struct ifinfo *ifi; 1092 char ntopbuf[INET6_ADDRSTRLEN]; 1093 char ifnamebuf[IFNAMSIZ]; 1094 union nd_opt ndopts; 1095 const char *on_off[] = {"OFF", "ON"}; 1096 uint32_t reachabletime, retranstimer, mtu; 1097 int inconsistent = 0; 1098 int error; 1099 1100 syslog(LOG_DEBUG, "<%s> RA received from %s on %s", __func__, 1101 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 1102 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 1103 1104 /* ND option check */ 1105 memset(&ndopts, 0, sizeof(ndopts)); 1106 TAILQ_INIT(&ndopts.opt_list); 1107 error = nd6_options((struct nd_opt_hdr *)(nra + 1), 1108 len - sizeof(struct nd_router_advert), &ndopts, 1109 NDOPT_FLAG_SRCLINKADDR | NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU | 1110 NDOPT_FLAG_RDNSS | NDOPT_FLAG_DNSSL); 1111 if (error) { 1112 syslog(LOG_INFO, 1113 "<%s> ND option check failed for an RA from %s on %s", 1114 __func__, 1115 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1116 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1117 ifnamebuf)); 1118 return; 1119 } 1120 1121 /* 1122 * RA consistency check according to RFC 4861 6.2.7 1123 */ 1124 ifi = if_indextoifinfo(pi->ipi6_ifindex); 1125 if (ifi->ifi_rainfo == NULL) { 1126 syslog(LOG_INFO, 1127 "<%s> received RA from %s on non-advertising" 1128 " interface(%s)", 1129 __func__, 1130 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1131 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1132 ifnamebuf)); 1133 goto done; 1134 } 1135 rai = ifi->ifi_rainfo; 1136 ifi->ifi_rainput++; 1137 syslog(LOG_DEBUG, "<%s> ifi->ifi_rainput = %" PRIu64, __func__, 1138 ifi->ifi_rainput); 1139 1140 /* Cur Hop Limit value */ 1141 if (nra->nd_ra_curhoplimit && rai->rai_hoplimit && 1142 nra->nd_ra_curhoplimit != rai->rai_hoplimit) { 1143 syslog(LOG_NOTICE, 1144 "CurHopLimit inconsistent on %s:" 1145 " %d from %s, %d from us", 1146 ifi->ifi_ifname, nra->nd_ra_curhoplimit, 1147 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1148 sizeof(ntopbuf)), rai->rai_hoplimit); 1149 inconsistent++; 1150 } 1151 /* M flag */ 1152 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) != 1153 rai->rai_managedflg) { 1154 syslog(LOG_NOTICE, 1155 "M flag inconsistent on %s:" 1156 " %s from %s, %s from us", 1157 ifi->ifi_ifname, on_off[!rai->rai_managedflg], 1158 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1159 sizeof(ntopbuf)), on_off[rai->rai_managedflg]); 1160 inconsistent++; 1161 } 1162 /* O flag */ 1163 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) != 1164 rai->rai_otherflg) { 1165 syslog(LOG_NOTICE, 1166 "O flag inconsistent on %s:" 1167 " %s from %s, %s from us", 1168 ifi->ifi_ifname, on_off[!rai->rai_otherflg], 1169 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1170 sizeof(ntopbuf)), on_off[rai->rai_otherflg]); 1171 inconsistent++; 1172 } 1173 /* Reachable Time */ 1174 reachabletime = ntohl(nra->nd_ra_reachable); 1175 if (reachabletime && rai->rai_reachabletime && 1176 reachabletime != rai->rai_reachabletime) { 1177 syslog(LOG_NOTICE, 1178 "ReachableTime inconsistent on %s:" 1179 " %d from %s, %d from us", 1180 ifi->ifi_ifname, reachabletime, 1181 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1182 sizeof(ntopbuf)), rai->rai_reachabletime); 1183 inconsistent++; 1184 } 1185 /* Retrans Timer */ 1186 retranstimer = ntohl(nra->nd_ra_retransmit); 1187 if (retranstimer && rai->rai_retranstimer && 1188 retranstimer != rai->rai_retranstimer) { 1189 syslog(LOG_NOTICE, 1190 "RetranceTimer inconsistent on %s:" 1191 " %d from %s, %d from us", 1192 ifi->ifi_ifname, retranstimer, 1193 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1194 sizeof(ntopbuf)), rai->rai_retranstimer); 1195 inconsistent++; 1196 } 1197 /* Values in the MTU options */ 1198 if (ndopts.opt_mtu) { 1199 mtu = ntohl(ndopts.opt_mtu->nd_opt_mtu_mtu); 1200 if (mtu && rai->rai_linkmtu && mtu != rai->rai_linkmtu) { 1201 syslog(LOG_NOTICE, 1202 "MTU option value inconsistent on %s:" 1203 " %d from %s, %d from us", 1204 ifi->ifi_ifname, mtu, 1205 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1206 sizeof(ntopbuf)), rai->rai_linkmtu); 1207 inconsistent++; 1208 } 1209 } 1210 /* Preferred and Valid Lifetimes for prefixes */ 1211 { 1212 struct nd_optlist *nol; 1213 1214 if (ndopts.opt_pi) 1215 if (prefix_check(ndopts.opt_pi, rai, from)) 1216 inconsistent++; 1217 1218 TAILQ_FOREACH(nol, &ndopts.opt_list, nol_next) 1219 if (prefix_check((struct nd_opt_prefix_info *)nol->nol_opt, 1220 rai, from)) 1221 inconsistent++; 1222 } 1223 1224 if (inconsistent) 1225 ifi->ifi_rainconsistent++; 1226 1227 done: 1228 free_ndopts(&ndopts); 1229 return; 1230 } 1231 1232 static uint32_t 1233 udiff(uint32_t u, uint32_t v) 1234 { 1235 return (u >= v ? u - v : v - u); 1236 } 1237 1238 /* return a non-zero value if the received prefix is inconsitent with ours */ 1239 static int 1240 prefix_check(struct nd_opt_prefix_info *pinfo, 1241 struct rainfo *rai, struct sockaddr_in6 *from) 1242 { 1243 struct ifinfo *ifi; 1244 uint32_t preferred_time, valid_time; 1245 struct prefix *pfx; 1246 int inconsistent = 0; 1247 char ntopbuf[INET6_ADDRSTRLEN]; 1248 char prefixbuf[INET6_ADDRSTRLEN]; 1249 struct timespec now; 1250 1251 #if 0 /* impossible */ 1252 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION) 1253 return (0); 1254 #endif 1255 ifi = rai->rai_ifinfo; 1256 /* 1257 * log if the adveritsed prefix has link-local scope(sanity check?) 1258 */ 1259 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) 1260 syslog(LOG_INFO, 1261 "<%s> link-local prefix %s/%d is advertised " 1262 "from %s on %s", 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 1270 if ((pfx = find_prefix(rai, &pinfo->nd_opt_pi_prefix, 1271 pinfo->nd_opt_pi_prefix_len)) == NULL) { 1272 syslog(LOG_INFO, 1273 "<%s> prefix %s/%d from %s on %s is not in our list", 1274 __func__, 1275 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1276 sizeof(prefixbuf)), 1277 pinfo->nd_opt_pi_prefix_len, 1278 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1279 sizeof(ntopbuf)), ifi->ifi_ifname); 1280 return (0); 1281 } 1282 1283 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time); 1284 if (pfx->pfx_pltimeexpire) { 1285 /* 1286 * The lifetime is decremented in real time, so we should 1287 * compare the expiration time. 1288 * (RFC 2461 Section 6.2.7.) 1289 * XXX: can we really expect that all routers on the link 1290 * have synchronized clocks? 1291 */ 1292 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1293 preferred_time += now.tv_sec; 1294 1295 if (!pfx->pfx_timer && rai->rai_clockskew && 1296 udiff(preferred_time, pfx->pfx_pltimeexpire) > rai->rai_clockskew) { 1297 syslog(LOG_INFO, 1298 "<%s> preferred lifetime for %s/%d" 1299 " (decr. in real time) inconsistent on %s:" 1300 " %" PRIu32 " from %s, %" PRIu32 " from us", 1301 __func__, 1302 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1303 sizeof(prefixbuf)), 1304 pinfo->nd_opt_pi_prefix_len, 1305 ifi->ifi_ifname, preferred_time, 1306 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1307 sizeof(ntopbuf)), pfx->pfx_pltimeexpire); 1308 inconsistent++; 1309 } 1310 } else if (!pfx->pfx_timer && preferred_time != pfx->pfx_preflifetime) 1311 syslog(LOG_INFO, 1312 "<%s> preferred lifetime for %s/%d" 1313 " inconsistent on %s:" 1314 " %d from %s, %d from us", 1315 __func__, 1316 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1317 sizeof(prefixbuf)), 1318 pinfo->nd_opt_pi_prefix_len, 1319 ifi->ifi_ifname, preferred_time, 1320 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1321 sizeof(ntopbuf)), pfx->pfx_preflifetime); 1322 1323 valid_time = ntohl(pinfo->nd_opt_pi_valid_time); 1324 if (pfx->pfx_vltimeexpire) { 1325 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1326 valid_time += now.tv_sec; 1327 1328 if (!pfx->pfx_timer && rai->rai_clockskew && 1329 udiff(valid_time, pfx->pfx_vltimeexpire) > rai->rai_clockskew) { 1330 syslog(LOG_INFO, 1331 "<%s> valid lifetime for %s/%d" 1332 " (decr. in real time) inconsistent on %s:" 1333 " %d from %s, %" PRIu32 " from us", 1334 __func__, 1335 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1336 sizeof(prefixbuf)), 1337 pinfo->nd_opt_pi_prefix_len, 1338 ifi->ifi_ifname, preferred_time, 1339 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1340 sizeof(ntopbuf)), pfx->pfx_vltimeexpire); 1341 inconsistent++; 1342 } 1343 } else if (!pfx->pfx_timer && valid_time != pfx->pfx_validlifetime) { 1344 syslog(LOG_INFO, 1345 "<%s> valid lifetime for %s/%d" 1346 " inconsistent on %s:" 1347 " %d from %s, %d from us", 1348 __func__, 1349 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1350 sizeof(prefixbuf)), 1351 pinfo->nd_opt_pi_prefix_len, 1352 ifi->ifi_ifname, valid_time, 1353 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1354 sizeof(ntopbuf)), pfx->pfx_validlifetime); 1355 inconsistent++; 1356 } 1357 1358 return (inconsistent); 1359 } 1360 1361 struct prefix * 1362 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen) 1363 { 1364 struct prefix *pfx; 1365 int bytelen, bitlen; 1366 char bitmask; 1367 1368 TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) { 1369 if (plen != pfx->pfx_prefixlen) 1370 continue; 1371 1372 bytelen = plen / 8; 1373 bitlen = plen % 8; 1374 bitmask = 0xff << (8 - bitlen); 1375 1376 if (memcmp((void *)prefix, (void *)&pfx->pfx_prefix, bytelen)) 1377 continue; 1378 1379 if (bitlen == 0 || 1380 ((prefix->s6_addr[bytelen] & bitmask) == 1381 (pfx->pfx_prefix.s6_addr[bytelen] & bitmask))) { 1382 return (pfx); 1383 } 1384 } 1385 1386 return (NULL); 1387 } 1388 1389 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */ 1390 int 1391 prefix_match(struct in6_addr *p0, int plen0, 1392 struct in6_addr *p1, int plen1) 1393 { 1394 int bytelen, bitlen; 1395 char bitmask; 1396 1397 if (plen0 < plen1) 1398 return (0); 1399 1400 bytelen = plen1 / 8; 1401 bitlen = plen1 % 8; 1402 bitmask = 0xff << (8 - bitlen); 1403 1404 if (memcmp((void *)p0, (void *)p1, bytelen)) 1405 return (0); 1406 1407 if (bitlen == 0 || 1408 ((p0->s6_addr[bytelen] & bitmask) == 1409 (p1->s6_addr[bytelen] & bitmask))) { 1410 return (1); 1411 } 1412 1413 return (0); 1414 } 1415 1416 static int 1417 nd6_options(struct nd_opt_hdr *hdr, int limit, 1418 union nd_opt *ndopts, uint32_t optflags) 1419 { 1420 int optlen = 0; 1421 1422 for (; limit > 0; limit -= optlen) { 1423 if ((size_t)limit < sizeof(struct nd_opt_hdr)) { 1424 syslog(LOG_INFO, "<%s> short option header", __func__); 1425 goto bad; 1426 } 1427 1428 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen); 1429 if (hdr->nd_opt_len == 0) { 1430 syslog(LOG_INFO, 1431 "<%s> bad ND option length(0) (type = %d)", 1432 __func__, hdr->nd_opt_type); 1433 goto bad; 1434 } 1435 optlen = hdr->nd_opt_len << 3; 1436 if (optlen > limit) { 1437 syslog(LOG_INFO, "<%s> short option", __func__); 1438 goto bad; 1439 } 1440 1441 if (hdr->nd_opt_type > ND_OPT_MTU && 1442 hdr->nd_opt_type != ND_OPT_RDNSS && 1443 hdr->nd_opt_type != ND_OPT_DNSSL) { 1444 syslog(LOG_INFO, "<%s> unknown ND option(type %d)", 1445 __func__, hdr->nd_opt_type); 1446 continue; 1447 } 1448 1449 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) { 1450 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)", 1451 __func__, hdr->nd_opt_type); 1452 continue; 1453 } 1454 1455 /* 1456 * Option length check. Do it here for all fixed-length 1457 * options. 1458 */ 1459 switch (hdr->nd_opt_type) { 1460 case ND_OPT_MTU: 1461 if (optlen == sizeof(struct nd_opt_mtu)) 1462 break; 1463 goto skip; 1464 case ND_OPT_RDNSS: 1465 if (optlen >= 24 && 1466 (optlen - sizeof(struct nd_opt_rdnss)) % 16 == 0) 1467 break; 1468 goto skip; 1469 case ND_OPT_DNSSL: 1470 if (optlen >= 16 && 1471 (optlen - sizeof(struct nd_opt_dnssl)) % 8 == 0) 1472 break; 1473 goto skip; 1474 case ND_OPT_PREFIX_INFORMATION: 1475 if (optlen == sizeof(struct nd_opt_prefix_info)) 1476 break; 1477 skip: 1478 syslog(LOG_INFO, "<%s> invalid option length", 1479 __func__); 1480 continue; 1481 } 1482 1483 switch (hdr->nd_opt_type) { 1484 case ND_OPT_TARGET_LINKADDR: 1485 case ND_OPT_REDIRECTED_HEADER: 1486 case ND_OPT_RDNSS: 1487 case ND_OPT_DNSSL: 1488 break; /* we don't care about these options */ 1489 case ND_OPT_SOURCE_LINKADDR: 1490 case ND_OPT_MTU: 1491 if (ndopts->opt_array[hdr->nd_opt_type]) { 1492 syslog(LOG_INFO, 1493 "<%s> duplicated ND option (type = %d)", 1494 __func__, hdr->nd_opt_type); 1495 } 1496 ndopts->opt_array[hdr->nd_opt_type] = hdr; 1497 break; 1498 case ND_OPT_PREFIX_INFORMATION: 1499 { 1500 struct nd_optlist *nol; 1501 1502 if (ndopts->opt_pi == 0) { 1503 ndopts->opt_pi = 1504 (struct nd_opt_prefix_info *)hdr; 1505 continue; 1506 } 1507 nol = malloc(sizeof(*nol)); 1508 if (nol == NULL) { 1509 syslog(LOG_ERR, "<%s> can't allocate memory", 1510 __func__); 1511 goto bad; 1512 } 1513 nol->nol_opt = hdr; 1514 TAILQ_INSERT_TAIL(&(ndopts->opt_list), nol, nol_next); 1515 1516 break; 1517 } 1518 default: /* impossible */ 1519 break; 1520 } 1521 } 1522 1523 return (0); 1524 1525 bad: 1526 free_ndopts(ndopts); 1527 1528 return (-1); 1529 } 1530 1531 static void 1532 free_ndopts(union nd_opt *ndopts) 1533 { 1534 struct nd_optlist *nol; 1535 1536 while ((nol = TAILQ_FIRST(&ndopts->opt_list)) != NULL) { 1537 TAILQ_REMOVE(&ndopts->opt_list, nol, nol_next); 1538 free(nol); 1539 } 1540 } 1541 1542 void 1543 sock_open(struct sockinfo *s) 1544 { 1545 struct icmp6_filter filt; 1546 int on; 1547 /* XXX: should be max MTU attached to the node */ 1548 static char answer[1500]; 1549 1550 syslog(LOG_DEBUG, "<%s> enter", __func__); 1551 1552 if (s == NULL) { 1553 syslog(LOG_ERR, "<%s> internal error", __func__); 1554 exit(1); 1555 } 1556 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1557 CMSG_SPACE(sizeof(int)); 1558 rcvcmsgbuf = (char *)malloc(rcvcmsgbuflen); 1559 if (rcvcmsgbuf == NULL) { 1560 syslog(LOG_ERR, "<%s> not enough core", __func__); 1561 exit(1); 1562 } 1563 1564 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1565 CMSG_SPACE(sizeof(int)); 1566 sndcmsgbuf = (char *)malloc(sndcmsgbuflen); 1567 if (sndcmsgbuf == NULL) { 1568 syslog(LOG_ERR, "<%s> not enough core", __func__); 1569 exit(1); 1570 } 1571 1572 if ((s->si_fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) { 1573 syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno)); 1574 exit(1); 1575 } 1576 /* specify to tell receiving interface */ 1577 on = 1; 1578 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 1579 sizeof(on)) < 0) { 1580 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", __func__, 1581 strerror(errno)); 1582 exit(1); 1583 } 1584 on = 1; 1585 /* specify to tell value of hoplimit field of received IP6 hdr */ 1586 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 1587 sizeof(on)) < 0) { 1588 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", __func__, 1589 strerror(errno)); 1590 exit(1); 1591 } 1592 ICMP6_FILTER_SETBLOCKALL(&filt); 1593 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt); 1594 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt); 1595 if (mcastif != NULL) 1596 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt); 1597 1598 if (setsockopt(s->si_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, 1599 sizeof(filt)) < 0) { 1600 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s", 1601 __func__, strerror(errno)); 1602 exit(1); 1603 } 1604 1605 /* initialize msghdr for receiving packets */ 1606 rcviov[0].iov_base = (caddr_t)answer; 1607 rcviov[0].iov_len = sizeof(answer); 1608 rcvmhdr.msg_name = (caddr_t)&rcvfrom; 1609 rcvmhdr.msg_namelen = sizeof(rcvfrom); 1610 rcvmhdr.msg_iov = rcviov; 1611 rcvmhdr.msg_iovlen = 1; 1612 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf; 1613 rcvmhdr.msg_controllen = rcvcmsgbuflen; 1614 1615 /* initialize msghdr for sending packets */ 1616 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6); 1617 sndmhdr.msg_iov = sndiov; 1618 sndmhdr.msg_iovlen = 1; 1619 sndmhdr.msg_control = (caddr_t)sndcmsgbuf; 1620 sndmhdr.msg_controllen = sndcmsgbuflen; 1621 1622 return; 1623 } 1624 1625 /* open a routing socket to watch the routing table */ 1626 static void 1627 rtsock_open(struct sockinfo *s) 1628 { 1629 if (s == NULL) { 1630 syslog(LOG_ERR, "<%s> internal error", __func__); 1631 exit(1); 1632 } 1633 if ((s->si_fd = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) { 1634 syslog(LOG_ERR, 1635 "<%s> socket: %s", __func__, strerror(errno)); 1636 exit(1); 1637 } 1638 } 1639 1640 struct ifinfo * 1641 if_indextoifinfo(int idx) 1642 { 1643 struct ifinfo *ifi; 1644 char name0[IFNAMSIZ]; 1645 1646 /* Check if the interface has a valid name or not. */ 1647 if (if_indextoname(idx, name0) == NULL) 1648 return (NULL); 1649 1650 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1651 if (ifi->ifi_ifindex == idx) 1652 return (ifi); 1653 } 1654 1655 if (ifi != NULL) 1656 syslog(LOG_DEBUG, "<%s> ifi found (idx=%d)", 1657 __func__, idx); 1658 else 1659 syslog(LOG_DEBUG, "<%s> ifi not found (idx=%d)", 1660 __func__, idx); 1661 1662 return (NULL); /* search failed */ 1663 } 1664 1665 void 1666 ra_output(struct ifinfo *ifi) 1667 { 1668 int i; 1669 struct cmsghdr *cm; 1670 struct in6_pktinfo *pi; 1671 struct soliciter *sol; 1672 struct rainfo *rai; 1673 1674 switch (ifi->ifi_state) { 1675 case IFI_STATE_CONFIGURED: 1676 rai = ifi->ifi_rainfo; 1677 break; 1678 case IFI_STATE_TRANSITIVE: 1679 rai = ifi->ifi_rainfo_trans; 1680 break; 1681 case IFI_STATE_UNCONFIGURED: 1682 syslog(LOG_DEBUG, "<%s> %s is unconfigured. " 1683 "Skip sending RAs.", 1684 __func__, ifi->ifi_ifname); 1685 return; 1686 default: 1687 rai = NULL; 1688 } 1689 if (rai == NULL) { 1690 syslog(LOG_DEBUG, "<%s> rainfo is NULL on %s." 1691 "Skip sending RAs.", 1692 __func__, ifi->ifi_ifname); 1693 return; 1694 } 1695 if (!(ifi->ifi_flags & IFF_UP)) { 1696 syslog(LOG_DEBUG, "<%s> %s is not up. " 1697 "Skip sending RAs.", 1698 __func__, ifi->ifi_ifname); 1699 return; 1700 } 1701 /* 1702 * Check lifetime, ACCEPT_RTADV flag, and ip6.forwarding. 1703 * 1704 * (lifetime == 0) = output 1705 * (lifetime != 0 && (check_accept_rtadv()) = no output 1706 * 1707 * Basically, hosts MUST NOT send Router Advertisement 1708 * messages at any time (RFC 4861, Section 6.2.3). However, it 1709 * would sometimes be useful to allow hosts to advertise some 1710 * parameters such as prefix information and link MTU. Thus, 1711 * we allow hosts to invoke rtadvd only when router lifetime 1712 * (on every advertising interface) is explicitly set 1713 * zero. (see also the above section) 1714 */ 1715 syslog(LOG_DEBUG, 1716 "<%s> check lifetime=%d, ACCEPT_RTADV=%d, ip6.forwarding=%d " 1717 "on %s", __func__, 1718 rai->rai_lifetime, 1719 check_accept_rtadv(ifi->ifi_ifindex), 1720 getinet6sysctl(IPV6CTL_FORWARDING), 1721 ifi->ifi_ifname); 1722 1723 if (rai->rai_lifetime != 0) { 1724 if (getinet6sysctl(IPV6CTL_FORWARDING) == 0) { 1725 syslog(LOG_ERR, 1726 "non-zero lifetime RA " 1727 "but net.inet6.ip6.forwarding=0. " 1728 "Ignored."); 1729 return; 1730 } 1731 if (check_accept_rtadv(ifi->ifi_ifindex)) { 1732 syslog(LOG_ERR, 1733 "non-zero lifetime RA " 1734 "on RA receiving interface %s." 1735 " Ignored.", ifi->ifi_ifname); 1736 return; 1737 } 1738 } 1739 1740 make_packet(rai); /* XXX: inefficient */ 1741 1742 sndmhdr.msg_name = (caddr_t)&sin6_linklocal_allnodes; 1743 sndmhdr.msg_iov[0].iov_base = (caddr_t)rai->rai_ra_data; 1744 sndmhdr.msg_iov[0].iov_len = rai->rai_ra_datalen; 1745 1746 cm = CMSG_FIRSTHDR(&sndmhdr); 1747 /* specify the outgoing interface */ 1748 cm->cmsg_level = IPPROTO_IPV6; 1749 cm->cmsg_type = IPV6_PKTINFO; 1750 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); 1751 pi = (struct in6_pktinfo *)CMSG_DATA(cm); 1752 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/ 1753 pi->ipi6_ifindex = ifi->ifi_ifindex; 1754 1755 /* specify the hop limit of the packet */ 1756 { 1757 int hoplimit = 255; 1758 1759 cm = CMSG_NXTHDR(&sndmhdr, cm); 1760 cm->cmsg_level = IPPROTO_IPV6; 1761 cm->cmsg_type = IPV6_HOPLIMIT; 1762 cm->cmsg_len = CMSG_LEN(sizeof(int)); 1763 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int)); 1764 } 1765 1766 syslog(LOG_DEBUG, 1767 "<%s> send RA on %s, # of RS waitings = %d", 1768 __func__, ifi->ifi_ifname, ifi->ifi_rs_waitcount); 1769 1770 i = sendmsg(sock.si_fd, &sndmhdr, 0); 1771 1772 if (i < 0 || (size_t)i != rai->rai_ra_datalen) { 1773 if (i < 0) { 1774 syslog(LOG_ERR, "<%s> sendmsg on %s: %s", 1775 __func__, ifi->ifi_ifname, 1776 strerror(errno)); 1777 } 1778 } 1779 1780 /* 1781 * unicast advertisements 1782 * XXX commented out. reason: though spec does not forbit it, unicast 1783 * advert does not really help 1784 */ 1785 while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) { 1786 TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next); 1787 free(sol); 1788 } 1789 1790 /* update timestamp */ 1791 clock_gettime(CLOCK_MONOTONIC_FAST, &ifi->ifi_ra_lastsent); 1792 1793 /* update counter */ 1794 ifi->ifi_rs_waitcount = 0; 1795 ifi->ifi_raoutput++; 1796 1797 switch (ifi->ifi_state) { 1798 case IFI_STATE_CONFIGURED: 1799 if (ifi->ifi_burstcount > 0) 1800 ifi->ifi_burstcount--; 1801 break; 1802 case IFI_STATE_TRANSITIVE: 1803 ifi->ifi_burstcount--; 1804 if (ifi->ifi_burstcount == 0) { 1805 if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) { 1806 /* Initial burst finished. */ 1807 if (ifi->ifi_rainfo_trans != NULL) 1808 ifi->ifi_rainfo_trans = NULL; 1809 } 1810 1811 /* Remove burst RA information */ 1812 if (ifi->ifi_rainfo_trans != NULL) { 1813 rm_rainfo(ifi->ifi_rainfo_trans); 1814 ifi->ifi_rainfo_trans = NULL; 1815 } 1816 1817 if (ifi->ifi_rainfo != NULL) { 1818 /* 1819 * TRANSITIVE -> CONFIGURED 1820 * 1821 * After initial burst or transition from 1822 * one configuration to another, 1823 * ifi_rainfo always points to the next RA 1824 * information. 1825 */ 1826 ifi->ifi_state = IFI_STATE_CONFIGURED; 1827 syslog(LOG_DEBUG, 1828 "<%s> ifname=%s marked as " 1829 "CONFIGURED.", __func__, 1830 ifi->ifi_ifname); 1831 } else { 1832 /* 1833 * TRANSITIVE -> UNCONFIGURED 1834 * 1835 * If ifi_rainfo points to NULL, this 1836 * interface is shutting down. 1837 * 1838 */ 1839 int error; 1840 1841 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 1842 syslog(LOG_DEBUG, 1843 "<%s> ifname=%s marked as " 1844 "UNCONFIGURED.", __func__, 1845 ifi->ifi_ifname); 1846 error = sock_mc_leave(&sock, 1847 ifi->ifi_ifindex); 1848 if (error) 1849 exit(1); 1850 } 1851 } 1852 break; 1853 } 1854 } 1855 1856 /* process RA timer */ 1857 struct rtadvd_timer * 1858 ra_timeout(void *arg) 1859 { 1860 struct ifinfo *ifi; 1861 1862 ifi = (struct ifinfo *)arg; 1863 syslog(LOG_DEBUG, "<%s> RA timer on %s is expired", 1864 __func__, ifi->ifi_ifname); 1865 1866 ra_output(ifi); 1867 1868 return (ifi->ifi_ra_timer); 1869 } 1870 1871 /* update RA timer */ 1872 void 1873 ra_timer_update(void *arg, struct timespec *tm) 1874 { 1875 uint16_t interval; 1876 struct rainfo *rai; 1877 struct ifinfo *ifi; 1878 1879 ifi = (struct ifinfo *)arg; 1880 rai = ifi->ifi_rainfo; 1881 interval = 0; 1882 1883 switch (ifi->ifi_state) { 1884 case IFI_STATE_UNCONFIGURED: 1885 return; 1886 break; 1887 case IFI_STATE_CONFIGURED: 1888 /* 1889 * Whenever a multicast advertisement is sent from 1890 * an interface, the timer is reset to a 1891 * uniformly-distributed random value between the 1892 * interface's configured MinRtrAdvInterval and 1893 * MaxRtrAdvInterval (RFC4861 6.2.4). 1894 */ 1895 interval = rai->rai_mininterval; 1896 #ifdef HAVE_ARC4RANDOM 1897 interval += arc4random_uniform(rai->rai_maxinterval - 1898 rai->rai_mininterval); 1899 #else 1900 interval += random() % (rai->rai_maxinterval - 1901 rai->rai_mininterval); 1902 #endif 1903 break; 1904 case IFI_STATE_TRANSITIVE: 1905 /* 1906 * For the first few advertisements (up to 1907 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen 1908 * interval is greater than 1909 * MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer SHOULD be 1910 * set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. (RFC 1911 * 4861 6.2.4) 1912 * 1913 * In such cases, the router SHOULD transmit one or more 1914 * (but not more than MAX_FINAL_RTR_ADVERTISEMENTS) final 1915 * multicast Router Advertisements on the interface with a 1916 * Router Lifetime field of zero. (RFC 4861 6.2.5) 1917 */ 1918 interval = ifi->ifi_burstinterval; 1919 break; 1920 } 1921 1922 tm->tv_sec = interval; 1923 tm->tv_nsec = 0; 1924 1925 syslog(LOG_DEBUG, 1926 "<%s> RA timer on %s is set to %ld:%ld", 1927 __func__, ifi->ifi_ifname, 1928 (long int)tm->tv_sec, (long int)tm->tv_nsec / 1000); 1929 1930 return; 1931 } 1932