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 srandomdev(); 248 #endif 249 pfh = pidfile_open(pidfilename, 0600, &otherpid); 250 if (pfh == NULL) { 251 if (errno == EEXIST) 252 errx(1, "%s already running, pid: %d", 253 getprogname(), otherpid); 254 syslog(LOG_ERR, 255 "failed to open the pid file %s, run anyway.", 256 pidfilename); 257 } 258 if (!fflag) 259 daemon(1, 0); 260 261 sock_open(&sock); 262 263 update_ifinfo(&ifilist, UPDATE_IFINFO_ALL); 264 for (i = 0; i < argc; i++) 265 update_persist_ifinfo(&ifilist, argv[i]); 266 267 csock_open(&ctrlsock, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH); 268 if (ctrlsock.si_fd == -1) { 269 syslog(LOG_ERR, "cannot open control socket: %s", 270 strerror(errno)); 271 exit(1); 272 } 273 274 /* record the current PID */ 275 pidfile_write(pfh); 276 277 set[PFD_RAWSOCK].fd = sock.si_fd; 278 set[PFD_RAWSOCK].events = POLLIN; 279 if (sflag == 0) { 280 rtsock_open(&rtsock); 281 set[PFD_RTSOCK].fd = rtsock.si_fd; 282 set[PFD_RTSOCK].events = POLLIN; 283 } else 284 set[PFD_RTSOCK].fd = -1; 285 set[PFD_CSOCK].fd = ctrlsock.si_fd; 286 set[PFD_CSOCK].events = POLLIN; 287 signal(SIGTERM, set_do_shutdown); 288 signal(SIGINT, set_do_shutdown); 289 signal(SIGHUP, set_do_reload); 290 291 error = csock_listen(&ctrlsock); 292 if (error) { 293 syslog(LOG_ERR, "cannot listen control socket: %s", 294 strerror(errno)); 295 exit(1); 296 } 297 298 /* load configuration file */ 299 set_do_reload(0); 300 301 while (1) { 302 if (is_do_shutdown()) 303 rtadvd_shutdown(); 304 305 if (is_do_reload()) { 306 loadconfig_ifname(reload_ifname()); 307 if (reload_ifname() == NULL) 308 syslog(LOG_INFO, 309 "configuration file reloaded."); 310 else 311 syslog(LOG_INFO, 312 "configuration file for %s reloaded.", 313 reload_ifname()); 314 reset_do_reload(); 315 } 316 317 /* timeout handler update for active interfaces */ 318 rtadvd_update_timeout_handler(); 319 320 /* timer expiration check and reset the timer */ 321 timeout = rtadvd_check_timer(); 322 323 if (timeout != NULL) { 324 syslog(LOG_DEBUG, 325 "<%s> set timer to %ld:%ld. waiting for " 326 "inputs or timeout", __func__, 327 (long int)timeout->tv_sec, 328 (long int)timeout->tv_nsec / 1000); 329 } else { 330 syslog(LOG_DEBUG, 331 "<%s> there's no timer. waiting for inputs", 332 __func__); 333 } 334 if ((i = poll(set, sizeof(set)/sizeof(set[0]), 335 timeout ? (timeout->tv_sec * 1000 + 336 timeout->tv_nsec / 1000 / 1000) : INFTIM)) < 0) { 337 338 /* EINTR would occur if a signal was delivered */ 339 if (errno != EINTR) 340 syslog(LOG_ERR, "poll() failed: %s", 341 strerror(errno)); 342 continue; 343 } 344 if (i == 0) /* timeout */ 345 continue; 346 if (rtsock.si_fd != -1 && set[PFD_RTSOCK].revents & POLLIN) 347 rtmsg_input(&rtsock); 348 349 if (set[PFD_RAWSOCK].revents & POLLIN) 350 rtadvd_input(&sock); 351 352 if (set[PFD_CSOCK].revents & POLLIN) { 353 int fd; 354 355 fd = csock_accept(&ctrlsock); 356 if (fd == -1) 357 syslog(LOG_ERR, 358 "cannot accept() control socket: %s", 359 strerror(errno)); 360 else { 361 cm_handler_server(fd); 362 close(fd); 363 } 364 } 365 } 366 exit(0); /* NOTREACHED */ 367 } 368 369 static void 370 rtadvd_shutdown(void) 371 { 372 struct ifinfo *ifi; 373 struct rainfo *rai; 374 struct rdnss *rdn; 375 struct dnssl *dns; 376 377 if (wait_shutdown) { 378 syslog(LOG_INFO, 379 "waiting expiration of the all RA timers."); 380 381 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 382 /* 383 * Ignore !IFF_UP interfaces in waiting for shutdown. 384 */ 385 if (!(ifi->ifi_flags & IFF_UP) && 386 ifi->ifi_ra_timer != NULL) { 387 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 388 rtadvd_remove_timer(ifi->ifi_ra_timer); 389 ifi->ifi_ra_timer = NULL; 390 syslog(LOG_DEBUG, "<%s> %s(idx=%d) is down. " 391 "Timer removed and marked as UNCONFIGURED.", 392 __func__, ifi->ifi_ifname, 393 ifi->ifi_ifindex); 394 } 395 } 396 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 397 if (ifi->ifi_ra_timer != NULL) 398 break; 399 } 400 if (ifi == NULL) { 401 syslog(LOG_NOTICE, "gracefully terminated."); 402 exit(0); 403 } 404 405 sleep(1); 406 return; 407 } 408 409 syslog(LOG_DEBUG, "<%s> cease to be an advertising router", 410 __func__); 411 412 wait_shutdown = 1; 413 414 TAILQ_FOREACH(rai, &railist, rai_next) { 415 rai->rai_lifetime = 0; 416 TAILQ_FOREACH(rdn, &rai->rai_rdnss, rd_next) 417 rdn->rd_ltime = 0; 418 TAILQ_FOREACH(dns, &rai->rai_dnssl, dn_next) 419 dns->dn_ltime = 0; 420 } 421 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 422 if (!ifi->ifi_persist) 423 continue; 424 if (ifi->ifi_state == IFI_STATE_UNCONFIGURED) 425 continue; 426 if (ifi->ifi_ra_timer == NULL) 427 continue; 428 if (ifi->ifi_ra_lastsent.tv_sec == 0 && 429 ifi->ifi_ra_lastsent.tv_nsec == 0 && 430 ifi->ifi_ra_timer != NULL) { 431 /* 432 * When RA configured but never sent, 433 * ignore the IF immediately. 434 */ 435 rtadvd_remove_timer(ifi->ifi_ra_timer); 436 ifi->ifi_ra_timer = NULL; 437 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 438 continue; 439 } 440 441 ifi->ifi_state = IFI_STATE_TRANSITIVE; 442 443 /* Mark as the shut-down state. */ 444 ifi->ifi_rainfo_trans = ifi->ifi_rainfo; 445 ifi->ifi_rainfo = NULL; 446 447 ifi->ifi_burstcount = MAX_FINAL_RTR_ADVERTISEMENTS; 448 ifi->ifi_burstinterval = MIN_DELAY_BETWEEN_RAS; 449 450 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm); 451 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm, 452 ifi->ifi_ra_timer); 453 } 454 syslog(LOG_NOTICE, "final RA transmission started."); 455 456 pidfile_remove(pfh); 457 csock_close(&ctrlsock); 458 } 459 460 static void 461 rtmsg_input(struct sockinfo *s) 462 { 463 int n, type, ifindex = 0, plen; 464 size_t len; 465 char msg[2048], *next, *lim; 466 char ifname[IFNAMSIZ]; 467 struct if_announcemsghdr *ifan; 468 struct rt_msghdr *rtm; 469 struct prefix *pfx; 470 struct rainfo *rai; 471 struct in6_addr *addr; 472 struct ifinfo *ifi; 473 char addrbuf[INET6_ADDRSTRLEN]; 474 int prefixchange = 0; 475 476 if (s == NULL) { 477 syslog(LOG_ERR, "<%s> internal error", __func__); 478 exit(1); 479 } 480 n = read(s->si_fd, msg, sizeof(msg)); 481 rtm = (struct rt_msghdr *)msg; 482 syslog(LOG_DEBUG, "<%s> received a routing message " 483 "(type = %d, len = %d)", __func__, rtm->rtm_type, n); 484 485 if (n > rtm->rtm_msglen) { 486 /* 487 * This usually won't happen for messages received on 488 * a routing socket. 489 */ 490 syslog(LOG_DEBUG, 491 "<%s> received data length is larger than " 492 "1st routing message len. multiple messages? " 493 "read %d bytes, but 1st msg len = %d", 494 __func__, n, rtm->rtm_msglen); 495 #if 0 496 /* adjust length */ 497 n = rtm->rtm_msglen; 498 #endif 499 } 500 501 lim = msg + n; 502 for (next = msg; next < lim; next += len) { 503 int oldifflags; 504 505 next = get_next_msg(next, lim, 0, &len, 506 RTADV_TYPE2BITMASK(RTM_ADD) | 507 RTADV_TYPE2BITMASK(RTM_DELETE) | 508 RTADV_TYPE2BITMASK(RTM_NEWADDR) | 509 RTADV_TYPE2BITMASK(RTM_DELADDR) | 510 RTADV_TYPE2BITMASK(RTM_IFINFO) | 511 RTADV_TYPE2BITMASK(RTM_IFANNOUNCE)); 512 if (len == 0) 513 break; 514 type = ((struct rt_msghdr *)next)->rtm_type; 515 switch (type) { 516 case RTM_ADD: 517 case RTM_DELETE: 518 ifindex = get_rtm_ifindex(next); 519 break; 520 case RTM_NEWADDR: 521 case RTM_DELADDR: 522 ifindex = (int)((struct ifa_msghdr *)next)->ifam_index; 523 break; 524 case RTM_IFINFO: 525 ifindex = (int)((struct if_msghdr *)next)->ifm_index; 526 break; 527 case RTM_IFANNOUNCE: 528 ifan = (struct if_announcemsghdr *)next; 529 switch (ifan->ifan_what) { 530 case IFAN_ARRIVAL: 531 case IFAN_DEPARTURE: 532 break; 533 default: 534 syslog(LOG_DEBUG, 535 "<%s:%d> unknown ifan msg (ifan_what=%d)", 536 __func__, __LINE__, ifan->ifan_what); 537 continue; 538 } 539 540 syslog(LOG_DEBUG, "<%s>: if_announcemsg (idx=%d:%d)", 541 __func__, ifan->ifan_index, ifan->ifan_what); 542 switch (ifan->ifan_what) { 543 case IFAN_ARRIVAL: 544 syslog(LOG_NOTICE, 545 "interface added (idx=%d)", 546 ifan->ifan_index); 547 update_ifinfo(&ifilist, ifan->ifan_index); 548 loadconfig_index(ifan->ifan_index); 549 break; 550 case IFAN_DEPARTURE: 551 syslog(LOG_NOTICE, 552 "interface removed (idx=%d)", 553 ifan->ifan_index); 554 rm_ifinfo_index(ifan->ifan_index); 555 556 /* Clear ifi_ifindex */ 557 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 558 if (ifi->ifi_ifindex 559 == ifan->ifan_index) { 560 ifi->ifi_ifindex = 0; 561 break; 562 } 563 } 564 update_ifinfo(&ifilist, ifan->ifan_index); 565 break; 566 } 567 continue; 568 default: 569 /* should not reach here */ 570 syslog(LOG_DEBUG, 571 "<%s:%d> unknown rtmsg %d on %s", 572 __func__, __LINE__, type, 573 if_indextoname(ifindex, ifname)); 574 continue; 575 } 576 ifi = if_indextoifinfo(ifindex); 577 if (ifi == NULL) { 578 syslog(LOG_DEBUG, 579 "<%s> ifinfo not found for idx=%d. Why?", 580 __func__, ifindex); 581 continue; 582 } 583 rai = ifi->ifi_rainfo; 584 if (rai == NULL) { 585 syslog(LOG_DEBUG, 586 "<%s> route changed on " 587 "non advertising interface(%s)", 588 __func__, ifi->ifi_ifname); 589 continue; 590 } 591 592 oldifflags = ifi->ifi_flags; 593 /* init ifflags because it may have changed */ 594 update_ifinfo(&ifilist, ifindex); 595 596 switch (type) { 597 case RTM_ADD: 598 if (sflag) 599 break; /* we aren't interested in prefixes */ 600 601 addr = get_addr(msg); 602 plen = get_prefixlen(msg); 603 /* sanity check for plen */ 604 /* as RFC2373, prefixlen is at least 4 */ 605 if (plen < 4 || plen > 127) { 606 syslog(LOG_INFO, "<%s> new interface route's" 607 "plen %d is invalid for a prefix", 608 __func__, plen); 609 break; 610 } 611 pfx = find_prefix(rai, addr, plen); 612 if (pfx) { 613 if (pfx->pfx_timer) { 614 /* 615 * If the prefix has been invalidated, 616 * make it available again. 617 */ 618 update_prefix(pfx); 619 prefixchange = 1; 620 } else 621 syslog(LOG_DEBUG, 622 "<%s> new prefix(%s/%d) " 623 "added on %s, " 624 "but it was already in list", 625 __func__, 626 inet_ntop(AF_INET6, addr, 627 (char *)addrbuf, 628 sizeof(addrbuf)), 629 plen, ifi->ifi_ifname); 630 break; 631 } 632 make_prefix(rai, ifindex, addr, plen); 633 prefixchange = 1; 634 break; 635 case RTM_DELETE: 636 if (sflag) 637 break; 638 639 addr = get_addr(msg); 640 plen = get_prefixlen(msg); 641 /* sanity check for plen */ 642 /* as RFC2373, prefixlen is at least 4 */ 643 if (plen < 4 || plen > 127) { 644 syslog(LOG_INFO, 645 "<%s> deleted interface route's " 646 "plen %d is invalid for a prefix", 647 __func__, plen); 648 break; 649 } 650 pfx = find_prefix(rai, addr, plen); 651 if (pfx == NULL) { 652 syslog(LOG_DEBUG, 653 "<%s> prefix(%s/%d) was deleted on %s, " 654 "but it was not in list", 655 __func__, inet_ntop(AF_INET6, addr, 656 (char *)addrbuf, sizeof(addrbuf)), 657 plen, ifi->ifi_ifname); 658 break; 659 } 660 invalidate_prefix(pfx); 661 prefixchange = 1; 662 break; 663 case RTM_NEWADDR: 664 case RTM_DELADDR: 665 case RTM_IFINFO: 666 break; 667 default: 668 /* should not reach here */ 669 syslog(LOG_DEBUG, 670 "<%s:%d> unknown rtmsg %d on %s", 671 __func__, __LINE__, type, 672 if_indextoname(ifindex, ifname)); 673 return; 674 } 675 676 /* check if an interface flag is changed */ 677 if ((oldifflags & IFF_UP) && /* UP to DOWN */ 678 !(ifi->ifi_flags & IFF_UP)) { 679 syslog(LOG_NOTICE, 680 "<interface %s becomes down. stop timer.", 681 ifi->ifi_ifname); 682 rtadvd_remove_timer(ifi->ifi_ra_timer); 683 ifi->ifi_ra_timer = NULL; 684 } else if (!(oldifflags & IFF_UP) && /* DOWN to UP */ 685 (ifi->ifi_flags & IFF_UP)) { 686 syslog(LOG_NOTICE, 687 "interface %s becomes up. restart timer.", 688 ifi->ifi_ifname); 689 690 ifi->ifi_state = IFI_STATE_TRANSITIVE; 691 ifi->ifi_burstcount = 692 MAX_INITIAL_RTR_ADVERTISEMENTS; 693 ifi->ifi_burstinterval = 694 MAX_INITIAL_RTR_ADVERT_INTERVAL; 695 696 ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout, 697 ra_timer_update, ifi, ifi); 698 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm); 699 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm, 700 ifi->ifi_ra_timer); 701 } else if (prefixchange && 702 (ifi->ifi_flags & IFF_UP)) { 703 /* 704 * An advertised prefix has been added or invalidated. 705 * Will notice the change in a short delay. 706 */ 707 set_short_delay(ifi); 708 } 709 } 710 711 return; 712 } 713 714 void 715 rtadvd_input(struct sockinfo *s) 716 { 717 ssize_t i; 718 int *hlimp = NULL; 719 #ifdef OLDRAWSOCKET 720 struct ip6_hdr *ip; 721 #endif 722 struct icmp6_hdr *icp; 723 int ifindex = 0; 724 struct cmsghdr *cm; 725 struct in6_pktinfo *pi = NULL; 726 char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; 727 struct in6_addr dst = in6addr_any; 728 struct ifinfo *ifi; 729 730 syslog(LOG_DEBUG, "<%s> enter", __func__); 731 732 if (s == NULL) { 733 syslog(LOG_ERR, "<%s> internal error", __func__); 734 exit(1); 735 } 736 /* 737 * Get message. We reset msg_controllen since the field could 738 * be modified if we had received a message before setting 739 * receive options. 740 */ 741 rcvmhdr.msg_controllen = rcvcmsgbuflen; 742 if ((i = recvmsg(s->si_fd, &rcvmhdr, 0)) < 0) 743 return; 744 745 /* extract optional information via Advanced API */ 746 for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr); 747 cm; 748 cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) { 749 if (cm->cmsg_level == IPPROTO_IPV6 && 750 cm->cmsg_type == IPV6_PKTINFO && 751 cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) { 752 pi = (struct in6_pktinfo *)(CMSG_DATA(cm)); 753 ifindex = pi->ipi6_ifindex; 754 dst = pi->ipi6_addr; 755 } 756 if (cm->cmsg_level == IPPROTO_IPV6 && 757 cm->cmsg_type == IPV6_HOPLIMIT && 758 cm->cmsg_len == CMSG_LEN(sizeof(int))) 759 hlimp = (int *)CMSG_DATA(cm); 760 } 761 if (ifindex == 0) { 762 syslog(LOG_ERR, "failed to get receiving interface"); 763 return; 764 } 765 if (hlimp == NULL) { 766 syslog(LOG_ERR, "failed to get receiving hop limit"); 767 return; 768 } 769 770 /* 771 * If we happen to receive data on an interface which is now gone 772 * or down, just discard the data. 773 */ 774 ifi = if_indextoifinfo(pi->ipi6_ifindex); 775 if (ifi == NULL || !(ifi->ifi_flags & IFF_UP)) { 776 syslog(LOG_INFO, 777 "<%s> received data on a disabled interface (%s)", 778 __func__, 779 (ifi == NULL) ? "[gone]" : ifi->ifi_ifname); 780 return; 781 } 782 783 #ifdef OLDRAWSOCKET 784 if ((size_t)i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) { 785 syslog(LOG_ERR, 786 "packet size(%d) is too short", i); 787 return; 788 } 789 790 ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base; 791 icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */ 792 #else 793 if ((size_t)i < sizeof(struct icmp6_hdr)) { 794 syslog(LOG_ERR, "packet size(%zd) is too short", i); 795 return; 796 } 797 798 icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base; 799 #endif 800 801 switch (icp->icmp6_type) { 802 case ND_ROUTER_SOLICIT: 803 /* 804 * Message verification - RFC 4861 6.1.1 805 * XXX: these checks must be done in the kernel as well, 806 * but we can't completely rely on them. 807 */ 808 if (*hlimp != 255) { 809 syslog(LOG_NOTICE, 810 "RS with invalid hop limit(%d) " 811 "received from %s on %s", 812 *hlimp, 813 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 814 sizeof(ntopbuf)), 815 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 816 return; 817 } 818 if (icp->icmp6_code) { 819 syslog(LOG_NOTICE, 820 "RS with invalid ICMP6 code(%d) " 821 "received from %s on %s", 822 icp->icmp6_code, 823 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 824 sizeof(ntopbuf)), 825 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 826 return; 827 } 828 if ((size_t)i < sizeof(struct nd_router_solicit)) { 829 syslog(LOG_NOTICE, 830 "RS from %s on %s does not have enough " 831 "length (len = %zd)", 832 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 833 sizeof(ntopbuf)), 834 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 835 return; 836 } 837 rs_input(i, (struct nd_router_solicit *)icp, pi, &rcvfrom); 838 break; 839 case ND_ROUTER_ADVERT: 840 /* 841 * Message verification - RFC 4861 6.1.2 842 * XXX: there's the same dilemma as above... 843 */ 844 if (!IN6_IS_ADDR_LINKLOCAL(&rcvfrom.sin6_addr)) { 845 syslog(LOG_NOTICE, 846 "RA with non-linklocal source address " 847 "received from %s on %s", 848 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, 849 ntopbuf, sizeof(ntopbuf)), 850 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 851 return; 852 } 853 if (*hlimp != 255) { 854 syslog(LOG_NOTICE, 855 "RA with invalid hop limit(%d) " 856 "received from %s on %s", 857 *hlimp, 858 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 859 sizeof(ntopbuf)), 860 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 861 return; 862 } 863 if (icp->icmp6_code) { 864 syslog(LOG_NOTICE, 865 "RA with invalid ICMP6 code(%d) " 866 "received from %s on %s", 867 icp->icmp6_code, 868 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 869 sizeof(ntopbuf)), 870 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 871 return; 872 } 873 if ((size_t)i < sizeof(struct nd_router_advert)) { 874 syslog(LOG_NOTICE, 875 "RA from %s on %s does not have enough " 876 "length (len = %zd)", 877 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 878 sizeof(ntopbuf)), 879 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 880 return; 881 } 882 ra_input(i, (struct nd_router_advert *)icp, pi, &rcvfrom); 883 break; 884 case ICMP6_ROUTER_RENUMBERING: 885 if (mcastif == NULL) { 886 syslog(LOG_ERR, "received a router renumbering " 887 "message, but not allowed to be accepted"); 888 break; 889 } 890 rr_input(i, (struct icmp6_router_renum *)icp, pi, &rcvfrom, 891 &dst); 892 break; 893 default: 894 /* 895 * Note that this case is POSSIBLE, especially just 896 * after invocation of the daemon. This is because we 897 * could receive message after opening the socket and 898 * before setting ICMP6 type filter(see sock_open()). 899 */ 900 syslog(LOG_ERR, "invalid icmp type(%d)", icp->icmp6_type); 901 return; 902 } 903 904 return; 905 } 906 907 static void 908 rs_input(int len, struct nd_router_solicit *rs, 909 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 910 { 911 char ntopbuf[INET6_ADDRSTRLEN]; 912 char ifnamebuf[IFNAMSIZ]; 913 union nd_opt ndopts; 914 struct rainfo *rai; 915 struct ifinfo *ifi; 916 struct soliciter *sol; 917 918 syslog(LOG_DEBUG, 919 "<%s> RS received from %s on %s", 920 __func__, 921 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 922 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 923 924 /* ND option check */ 925 memset(&ndopts, 0, sizeof(ndopts)); 926 TAILQ_INIT(&ndopts.opt_list); 927 if (nd6_options((struct nd_opt_hdr *)(rs + 1), 928 len - sizeof(struct nd_router_solicit), 929 &ndopts, NDOPT_FLAG_SRCLINKADDR)) { 930 syslog(LOG_INFO, 931 "<%s> ND option check failed for an RS from %s on %s", 932 __func__, 933 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 934 sizeof(ntopbuf)), 935 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 936 return; 937 } 938 939 /* 940 * If the IP source address is the unspecified address, there 941 * must be no source link-layer address option in the message. 942 * (RFC 4861 6.1.1) 943 */ 944 if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) && 945 ndopts.opt_src_lladdr) { 946 syslog(LOG_INFO, 947 "<%s> RS from unspecified src on %s has a link-layer" 948 " address option", 949 __func__, if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 950 goto done; 951 } 952 953 ifi = if_indextoifinfo(pi->ipi6_ifindex); 954 if (ifi == NULL) { 955 syslog(LOG_INFO, 956 "<%s> if (idx=%d) not found. Why?", 957 __func__, pi->ipi6_ifindex); 958 goto done; 959 } 960 rai = ifi->ifi_rainfo; 961 if (rai == NULL) { 962 syslog(LOG_INFO, 963 "<%s> RS received on non advertising interface(%s)", 964 __func__, 965 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 966 goto done; 967 } 968 969 rai->rai_ifinfo->ifi_rsinput++; 970 971 /* 972 * Decide whether to send RA according to the rate-limit 973 * consideration. 974 */ 975 976 /* record sockaddr waiting for RA, if possible */ 977 sol = (struct soliciter *)malloc(sizeof(*sol)); 978 if (sol) { 979 sol->sol_addr = *from; 980 /* XXX RFC 2553 need clarification on flowinfo */ 981 sol->sol_addr.sin6_flowinfo = 0; 982 TAILQ_INSERT_TAIL(&rai->rai_soliciter, sol, sol_next); 983 } 984 985 /* 986 * If there is already a waiting RS packet, don't 987 * update the timer. 988 */ 989 if (ifi->ifi_rs_waitcount++) 990 goto done; 991 992 set_short_delay(ifi); 993 994 done: 995 free_ndopts(&ndopts); 996 return; 997 } 998 999 static void 1000 set_short_delay(struct ifinfo *ifi) 1001 { 1002 long delay; /* must not be greater than 1000000 */ 1003 struct timespec interval, now, min_delay, tm_tmp, *rest; 1004 1005 if (ifi->ifi_ra_timer == NULL) 1006 return; 1007 /* 1008 * Compute a random delay. If the computed value 1009 * corresponds to a time later than the time the next 1010 * multicast RA is scheduled to be sent, ignore the random 1011 * delay and send the advertisement at the 1012 * already-scheduled time. RFC 4861 6.2.6 1013 */ 1014 #ifdef HAVE_ARC4RANDOM 1015 delay = arc4random_uniform(MAX_RA_DELAY_TIME); 1016 #else 1017 delay = random() % MAX_RA_DELAY_TIME; 1018 #endif 1019 interval.tv_sec = 0; 1020 interval.tv_nsec = delay * 1000; 1021 rest = rtadvd_timer_rest(ifi->ifi_ra_timer); 1022 if (TS_CMP(rest, &interval, <)) { 1023 syslog(LOG_DEBUG, "<%s> random delay is larger than " 1024 "the rest of the current timer", __func__); 1025 interval = *rest; 1026 } 1027 1028 /* 1029 * If we sent a multicast Router Advertisement within 1030 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule 1031 * the advertisement to be sent at a time corresponding to 1032 * MIN_DELAY_BETWEEN_RAS plus the random value after the 1033 * previous advertisement was sent. 1034 */ 1035 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1036 TS_SUB(&now, &ifi->ifi_ra_lastsent, &tm_tmp); 1037 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS; 1038 min_delay.tv_nsec = 0; 1039 if (TS_CMP(&tm_tmp, &min_delay, <)) { 1040 TS_SUB(&min_delay, &tm_tmp, &min_delay); 1041 TS_ADD(&min_delay, &interval, &interval); 1042 } 1043 rtadvd_set_timer(&interval, ifi->ifi_ra_timer); 1044 } 1045 1046 static int 1047 check_accept_rtadv(int idx) 1048 { 1049 struct ifinfo *ifi; 1050 1051 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1052 if (ifi->ifi_ifindex == idx) 1053 break; 1054 } 1055 if (ifi == NULL) { 1056 syslog(LOG_DEBUG, 1057 "<%s> if (idx=%d) not found. Why?", 1058 __func__, idx); 1059 return (0); 1060 } 1061 /* 1062 * RA_RECV: ND6_IFF_ACCEPT_RTADV 1063 * RA_SEND: ip6.forwarding 1064 */ 1065 if (update_ifinfo_nd_flags(ifi) != 0) { 1066 syslog(LOG_ERR, "cannot get nd6 flags (idx=%d)", idx); 1067 return (0); 1068 } 1069 1070 return (ifi->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV); 1071 } 1072 1073 static void 1074 ra_input(int len, struct nd_router_advert *nra, 1075 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 1076 { 1077 struct rainfo *rai; 1078 struct ifinfo *ifi; 1079 char ntopbuf[INET6_ADDRSTRLEN]; 1080 char ifnamebuf[IFNAMSIZ]; 1081 union nd_opt ndopts; 1082 const char *on_off[] = {"OFF", "ON"}; 1083 uint32_t reachabletime, retranstimer, mtu; 1084 int inconsistent = 0; 1085 int error; 1086 1087 syslog(LOG_DEBUG, "<%s> RA received from %s on %s", __func__, 1088 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 1089 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 1090 1091 /* ND option check */ 1092 memset(&ndopts, 0, sizeof(ndopts)); 1093 TAILQ_INIT(&ndopts.opt_list); 1094 error = nd6_options((struct nd_opt_hdr *)(nra + 1), 1095 len - sizeof(struct nd_router_advert), &ndopts, 1096 NDOPT_FLAG_SRCLINKADDR | NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU | 1097 NDOPT_FLAG_RDNSS | NDOPT_FLAG_DNSSL); 1098 if (error) { 1099 syslog(LOG_INFO, 1100 "<%s> ND option check failed for an RA from %s on %s", 1101 __func__, 1102 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1103 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1104 ifnamebuf)); 1105 return; 1106 } 1107 1108 /* 1109 * RA consistency check according to RFC 4861 6.2.7 1110 */ 1111 ifi = if_indextoifinfo(pi->ipi6_ifindex); 1112 if (ifi->ifi_rainfo == NULL) { 1113 syslog(LOG_INFO, 1114 "<%s> received RA from %s on non-advertising" 1115 " interface(%s)", 1116 __func__, 1117 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1118 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1119 ifnamebuf)); 1120 goto done; 1121 } 1122 rai = ifi->ifi_rainfo; 1123 ifi->ifi_rainput++; 1124 syslog(LOG_DEBUG, "<%s> ifi->ifi_rainput = %" PRIu64, __func__, 1125 ifi->ifi_rainput); 1126 1127 /* Cur Hop Limit value */ 1128 if (nra->nd_ra_curhoplimit && rai->rai_hoplimit && 1129 nra->nd_ra_curhoplimit != rai->rai_hoplimit) { 1130 syslog(LOG_NOTICE, 1131 "CurHopLimit inconsistent on %s:" 1132 " %d from %s, %d from us", 1133 ifi->ifi_ifname, nra->nd_ra_curhoplimit, 1134 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1135 sizeof(ntopbuf)), rai->rai_hoplimit); 1136 inconsistent++; 1137 } 1138 /* M flag */ 1139 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) != 1140 rai->rai_managedflg) { 1141 syslog(LOG_NOTICE, 1142 "M flag inconsistent on %s:" 1143 " %s from %s, %s from us", 1144 ifi->ifi_ifname, on_off[!rai->rai_managedflg], 1145 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1146 sizeof(ntopbuf)), on_off[rai->rai_managedflg]); 1147 inconsistent++; 1148 } 1149 /* O flag */ 1150 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) != 1151 rai->rai_otherflg) { 1152 syslog(LOG_NOTICE, 1153 "O flag inconsistent on %s:" 1154 " %s from %s, %s from us", 1155 ifi->ifi_ifname, on_off[!rai->rai_otherflg], 1156 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1157 sizeof(ntopbuf)), on_off[rai->rai_otherflg]); 1158 inconsistent++; 1159 } 1160 /* Reachable Time */ 1161 reachabletime = ntohl(nra->nd_ra_reachable); 1162 if (reachabletime && rai->rai_reachabletime && 1163 reachabletime != rai->rai_reachabletime) { 1164 syslog(LOG_NOTICE, 1165 "ReachableTime inconsistent on %s:" 1166 " %d from %s, %d from us", 1167 ifi->ifi_ifname, reachabletime, 1168 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1169 sizeof(ntopbuf)), rai->rai_reachabletime); 1170 inconsistent++; 1171 } 1172 /* Retrans Timer */ 1173 retranstimer = ntohl(nra->nd_ra_retransmit); 1174 if (retranstimer && rai->rai_retranstimer && 1175 retranstimer != rai->rai_retranstimer) { 1176 syslog(LOG_NOTICE, 1177 "RetranceTimer inconsistent on %s:" 1178 " %d from %s, %d from us", 1179 ifi->ifi_ifname, retranstimer, 1180 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1181 sizeof(ntopbuf)), rai->rai_retranstimer); 1182 inconsistent++; 1183 } 1184 /* Values in the MTU options */ 1185 if (ndopts.opt_mtu) { 1186 mtu = ntohl(ndopts.opt_mtu->nd_opt_mtu_mtu); 1187 if (mtu && rai->rai_linkmtu && mtu != rai->rai_linkmtu) { 1188 syslog(LOG_NOTICE, 1189 "MTU option value inconsistent on %s:" 1190 " %d from %s, %d from us", 1191 ifi->ifi_ifname, mtu, 1192 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1193 sizeof(ntopbuf)), rai->rai_linkmtu); 1194 inconsistent++; 1195 } 1196 } 1197 /* Preferred and Valid Lifetimes for prefixes */ 1198 { 1199 struct nd_optlist *nol; 1200 1201 if (ndopts.opt_pi) 1202 if (prefix_check(ndopts.opt_pi, rai, from)) 1203 inconsistent++; 1204 1205 TAILQ_FOREACH(nol, &ndopts.opt_list, nol_next) 1206 if (prefix_check((struct nd_opt_prefix_info *)nol->nol_opt, 1207 rai, from)) 1208 inconsistent++; 1209 } 1210 1211 if (inconsistent) 1212 ifi->ifi_rainconsistent++; 1213 1214 done: 1215 free_ndopts(&ndopts); 1216 return; 1217 } 1218 1219 static uint32_t 1220 udiff(uint32_t u, uint32_t v) 1221 { 1222 return (u >= v ? u - v : v - u); 1223 } 1224 1225 /* return a non-zero value if the received prefix is inconsitent with ours */ 1226 static int 1227 prefix_check(struct nd_opt_prefix_info *pinfo, 1228 struct rainfo *rai, struct sockaddr_in6 *from) 1229 { 1230 struct ifinfo *ifi; 1231 uint32_t preferred_time, valid_time; 1232 struct prefix *pfx; 1233 int inconsistent = 0; 1234 char ntopbuf[INET6_ADDRSTRLEN]; 1235 char prefixbuf[INET6_ADDRSTRLEN]; 1236 struct timespec now; 1237 1238 #if 0 /* impossible */ 1239 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION) 1240 return (0); 1241 #endif 1242 ifi = rai->rai_ifinfo; 1243 /* 1244 * log if the adveritsed prefix has link-local scope(sanity check?) 1245 */ 1246 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) 1247 syslog(LOG_INFO, 1248 "<%s> link-local prefix %s/%d is advertised " 1249 "from %s on %s", 1250 __func__, 1251 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1252 sizeof(prefixbuf)), 1253 pinfo->nd_opt_pi_prefix_len, 1254 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1255 sizeof(ntopbuf)), ifi->ifi_ifname); 1256 1257 if ((pfx = find_prefix(rai, &pinfo->nd_opt_pi_prefix, 1258 pinfo->nd_opt_pi_prefix_len)) == NULL) { 1259 syslog(LOG_INFO, 1260 "<%s> prefix %s/%d from %s on %s is not in our list", 1261 __func__, 1262 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1263 sizeof(prefixbuf)), 1264 pinfo->nd_opt_pi_prefix_len, 1265 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1266 sizeof(ntopbuf)), ifi->ifi_ifname); 1267 return (0); 1268 } 1269 1270 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time); 1271 if (pfx->pfx_pltimeexpire) { 1272 /* 1273 * The lifetime is decremented in real time, so we should 1274 * compare the expiration time. 1275 * (RFC 2461 Section 6.2.7.) 1276 * XXX: can we really expect that all routers on the link 1277 * have synchronized clocks? 1278 */ 1279 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1280 preferred_time += now.tv_sec; 1281 1282 if (!pfx->pfx_timer && rai->rai_clockskew && 1283 udiff(preferred_time, pfx->pfx_pltimeexpire) > rai->rai_clockskew) { 1284 syslog(LOG_INFO, 1285 "<%s> preferred lifetime for %s/%d" 1286 " (decr. in real time) inconsistent on %s:" 1287 " %" PRIu32 " from %s, %" PRIu32 " from us", 1288 __func__, 1289 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1290 sizeof(prefixbuf)), 1291 pinfo->nd_opt_pi_prefix_len, 1292 ifi->ifi_ifname, preferred_time, 1293 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1294 sizeof(ntopbuf)), pfx->pfx_pltimeexpire); 1295 inconsistent++; 1296 } 1297 } else if (!pfx->pfx_timer && preferred_time != pfx->pfx_preflifetime) 1298 syslog(LOG_INFO, 1299 "<%s> preferred lifetime for %s/%d" 1300 " inconsistent on %s:" 1301 " %d from %s, %d from us", 1302 __func__, 1303 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1304 sizeof(prefixbuf)), 1305 pinfo->nd_opt_pi_prefix_len, 1306 ifi->ifi_ifname, preferred_time, 1307 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1308 sizeof(ntopbuf)), pfx->pfx_preflifetime); 1309 1310 valid_time = ntohl(pinfo->nd_opt_pi_valid_time); 1311 if (pfx->pfx_vltimeexpire) { 1312 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1313 valid_time += now.tv_sec; 1314 1315 if (!pfx->pfx_timer && rai->rai_clockskew && 1316 udiff(valid_time, pfx->pfx_vltimeexpire) > rai->rai_clockskew) { 1317 syslog(LOG_INFO, 1318 "<%s> valid lifetime for %s/%d" 1319 " (decr. in real time) inconsistent on %s:" 1320 " %d from %s, %" PRIu32 " from us", 1321 __func__, 1322 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1323 sizeof(prefixbuf)), 1324 pinfo->nd_opt_pi_prefix_len, 1325 ifi->ifi_ifname, preferred_time, 1326 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1327 sizeof(ntopbuf)), pfx->pfx_vltimeexpire); 1328 inconsistent++; 1329 } 1330 } else if (!pfx->pfx_timer && valid_time != pfx->pfx_validlifetime) { 1331 syslog(LOG_INFO, 1332 "<%s> valid lifetime for %s/%d" 1333 " inconsistent on %s:" 1334 " %d from %s, %d from us", 1335 __func__, 1336 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1337 sizeof(prefixbuf)), 1338 pinfo->nd_opt_pi_prefix_len, 1339 ifi->ifi_ifname, valid_time, 1340 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1341 sizeof(ntopbuf)), pfx->pfx_validlifetime); 1342 inconsistent++; 1343 } 1344 1345 return (inconsistent); 1346 } 1347 1348 struct prefix * 1349 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen) 1350 { 1351 struct prefix *pfx; 1352 int bytelen, bitlen; 1353 char bitmask; 1354 1355 TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) { 1356 if (plen != pfx->pfx_prefixlen) 1357 continue; 1358 1359 bytelen = plen / 8; 1360 bitlen = plen % 8; 1361 bitmask = 0xff << (8 - bitlen); 1362 1363 if (memcmp((void *)prefix, (void *)&pfx->pfx_prefix, bytelen)) 1364 continue; 1365 1366 if (bitlen == 0 || 1367 ((prefix->s6_addr[bytelen] & bitmask) == 1368 (pfx->pfx_prefix.s6_addr[bytelen] & bitmask))) { 1369 return (pfx); 1370 } 1371 } 1372 1373 return (NULL); 1374 } 1375 1376 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */ 1377 int 1378 prefix_match(struct in6_addr *p0, int plen0, 1379 struct in6_addr *p1, int plen1) 1380 { 1381 int bytelen, bitlen; 1382 char bitmask; 1383 1384 if (plen0 < plen1) 1385 return (0); 1386 1387 bytelen = plen1 / 8; 1388 bitlen = plen1 % 8; 1389 bitmask = 0xff << (8 - bitlen); 1390 1391 if (memcmp((void *)p0, (void *)p1, bytelen)) 1392 return (0); 1393 1394 if (bitlen == 0 || 1395 ((p0->s6_addr[bytelen] & bitmask) == 1396 (p1->s6_addr[bytelen] & bitmask))) { 1397 return (1); 1398 } 1399 1400 return (0); 1401 } 1402 1403 static int 1404 nd6_options(struct nd_opt_hdr *hdr, int limit, 1405 union nd_opt *ndopts, uint32_t optflags) 1406 { 1407 int optlen = 0; 1408 1409 for (; limit > 0; limit -= optlen) { 1410 if ((size_t)limit < sizeof(struct nd_opt_hdr)) { 1411 syslog(LOG_INFO, "<%s> short option header", __func__); 1412 goto bad; 1413 } 1414 1415 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen); 1416 if (hdr->nd_opt_len == 0) { 1417 syslog(LOG_INFO, 1418 "<%s> bad ND option length(0) (type = %d)", 1419 __func__, hdr->nd_opt_type); 1420 goto bad; 1421 } 1422 optlen = hdr->nd_opt_len << 3; 1423 if (optlen > limit) { 1424 syslog(LOG_INFO, "<%s> short option", __func__); 1425 goto bad; 1426 } 1427 1428 if (hdr->nd_opt_type > ND_OPT_MTU && 1429 hdr->nd_opt_type != ND_OPT_RDNSS && 1430 hdr->nd_opt_type != ND_OPT_DNSSL) { 1431 syslog(LOG_INFO, "<%s> unknown ND option(type %d)", 1432 __func__, hdr->nd_opt_type); 1433 continue; 1434 } 1435 1436 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) { 1437 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)", 1438 __func__, hdr->nd_opt_type); 1439 continue; 1440 } 1441 1442 /* 1443 * Option length check. Do it here for all fixed-length 1444 * options. 1445 */ 1446 switch (hdr->nd_opt_type) { 1447 case ND_OPT_MTU: 1448 if (optlen == sizeof(struct nd_opt_mtu)) 1449 break; 1450 goto skip; 1451 case ND_OPT_RDNSS: 1452 if (optlen >= 24 && 1453 (optlen - sizeof(struct nd_opt_rdnss)) % 16 == 0) 1454 break; 1455 goto skip; 1456 case ND_OPT_DNSSL: 1457 if (optlen >= 16 && 1458 (optlen - sizeof(struct nd_opt_dnssl)) % 8 == 0) 1459 break; 1460 goto skip; 1461 case ND_OPT_PREFIX_INFORMATION: 1462 if (optlen == sizeof(struct nd_opt_prefix_info)) 1463 break; 1464 skip: 1465 syslog(LOG_INFO, "<%s> invalid option length", 1466 __func__); 1467 continue; 1468 } 1469 1470 switch (hdr->nd_opt_type) { 1471 case ND_OPT_TARGET_LINKADDR: 1472 case ND_OPT_REDIRECTED_HEADER: 1473 case ND_OPT_RDNSS: 1474 case ND_OPT_DNSSL: 1475 break; /* we don't care about these options */ 1476 case ND_OPT_SOURCE_LINKADDR: 1477 case ND_OPT_MTU: 1478 if (ndopts->opt_array[hdr->nd_opt_type]) { 1479 syslog(LOG_INFO, 1480 "<%s> duplicated ND option (type = %d)", 1481 __func__, hdr->nd_opt_type); 1482 } 1483 ndopts->opt_array[hdr->nd_opt_type] = hdr; 1484 break; 1485 case ND_OPT_PREFIX_INFORMATION: 1486 { 1487 struct nd_optlist *nol; 1488 1489 if (ndopts->opt_pi == 0) { 1490 ndopts->opt_pi = 1491 (struct nd_opt_prefix_info *)hdr; 1492 continue; 1493 } 1494 nol = malloc(sizeof(*nol)); 1495 if (nol == NULL) { 1496 syslog(LOG_ERR, "<%s> can't allocate memory", 1497 __func__); 1498 goto bad; 1499 } 1500 nol->nol_opt = hdr; 1501 TAILQ_INSERT_TAIL(&(ndopts->opt_list), nol, nol_next); 1502 1503 break; 1504 } 1505 default: /* impossible */ 1506 break; 1507 } 1508 } 1509 1510 return (0); 1511 1512 bad: 1513 free_ndopts(ndopts); 1514 1515 return (-1); 1516 } 1517 1518 static void 1519 free_ndopts(union nd_opt *ndopts) 1520 { 1521 struct nd_optlist *nol; 1522 1523 while ((nol = TAILQ_FIRST(&ndopts->opt_list)) != NULL) { 1524 TAILQ_REMOVE(&ndopts->opt_list, nol, nol_next); 1525 free(nol); 1526 } 1527 } 1528 1529 void 1530 sock_open(struct sockinfo *s) 1531 { 1532 struct icmp6_filter filt; 1533 int on; 1534 /* XXX: should be max MTU attached to the node */ 1535 static char answer[1500]; 1536 1537 syslog(LOG_DEBUG, "<%s> enter", __func__); 1538 1539 if (s == NULL) { 1540 syslog(LOG_ERR, "<%s> internal error", __func__); 1541 exit(1); 1542 } 1543 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1544 CMSG_SPACE(sizeof(int)); 1545 rcvcmsgbuf = (char *)malloc(rcvcmsgbuflen); 1546 if (rcvcmsgbuf == NULL) { 1547 syslog(LOG_ERR, "<%s> not enough core", __func__); 1548 exit(1); 1549 } 1550 1551 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1552 CMSG_SPACE(sizeof(int)); 1553 sndcmsgbuf = (char *)malloc(sndcmsgbuflen); 1554 if (sndcmsgbuf == NULL) { 1555 syslog(LOG_ERR, "<%s> not enough core", __func__); 1556 exit(1); 1557 } 1558 1559 if ((s->si_fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) { 1560 syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno)); 1561 exit(1); 1562 } 1563 /* specify to tell receiving interface */ 1564 on = 1; 1565 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 1566 sizeof(on)) < 0) { 1567 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", __func__, 1568 strerror(errno)); 1569 exit(1); 1570 } 1571 on = 1; 1572 /* specify to tell value of hoplimit field of received IP6 hdr */ 1573 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 1574 sizeof(on)) < 0) { 1575 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", __func__, 1576 strerror(errno)); 1577 exit(1); 1578 } 1579 ICMP6_FILTER_SETBLOCKALL(&filt); 1580 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt); 1581 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt); 1582 if (mcastif != NULL) 1583 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt); 1584 1585 if (setsockopt(s->si_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, 1586 sizeof(filt)) < 0) { 1587 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s", 1588 __func__, strerror(errno)); 1589 exit(1); 1590 } 1591 1592 /* initialize msghdr for receiving packets */ 1593 rcviov[0].iov_base = (caddr_t)answer; 1594 rcviov[0].iov_len = sizeof(answer); 1595 rcvmhdr.msg_name = (caddr_t)&rcvfrom; 1596 rcvmhdr.msg_namelen = sizeof(rcvfrom); 1597 rcvmhdr.msg_iov = rcviov; 1598 rcvmhdr.msg_iovlen = 1; 1599 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf; 1600 rcvmhdr.msg_controllen = rcvcmsgbuflen; 1601 1602 /* initialize msghdr for sending packets */ 1603 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6); 1604 sndmhdr.msg_iov = sndiov; 1605 sndmhdr.msg_iovlen = 1; 1606 sndmhdr.msg_control = (caddr_t)sndcmsgbuf; 1607 sndmhdr.msg_controllen = sndcmsgbuflen; 1608 1609 return; 1610 } 1611 1612 /* open a routing socket to watch the routing table */ 1613 static void 1614 rtsock_open(struct sockinfo *s) 1615 { 1616 if (s == NULL) { 1617 syslog(LOG_ERR, "<%s> internal error", __func__); 1618 exit(1); 1619 } 1620 if ((s->si_fd = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) { 1621 syslog(LOG_ERR, 1622 "<%s> socket: %s", __func__, strerror(errno)); 1623 exit(1); 1624 } 1625 } 1626 1627 struct ifinfo * 1628 if_indextoifinfo(int idx) 1629 { 1630 struct ifinfo *ifi; 1631 char name0[IFNAMSIZ]; 1632 1633 /* Check if the interface has a valid name or not. */ 1634 if (if_indextoname(idx, name0) == NULL) 1635 return (NULL); 1636 1637 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1638 if (ifi->ifi_ifindex == idx) 1639 return (ifi); 1640 } 1641 1642 if (ifi != NULL) 1643 syslog(LOG_DEBUG, "<%s> ifi found (idx=%d)", 1644 __func__, idx); 1645 else 1646 syslog(LOG_DEBUG, "<%s> ifi not found (idx=%d)", 1647 __func__, idx); 1648 1649 return (NULL); /* search failed */ 1650 } 1651 1652 void 1653 ra_output(struct ifinfo *ifi) 1654 { 1655 int i; 1656 struct cmsghdr *cm; 1657 struct in6_pktinfo *pi; 1658 struct soliciter *sol; 1659 struct rainfo *rai; 1660 1661 switch (ifi->ifi_state) { 1662 case IFI_STATE_CONFIGURED: 1663 rai = ifi->ifi_rainfo; 1664 break; 1665 case IFI_STATE_TRANSITIVE: 1666 rai = ifi->ifi_rainfo_trans; 1667 break; 1668 case IFI_STATE_UNCONFIGURED: 1669 syslog(LOG_DEBUG, "<%s> %s is unconfigured. " 1670 "Skip sending RAs.", 1671 __func__, ifi->ifi_ifname); 1672 return; 1673 default: 1674 rai = NULL; 1675 } 1676 if (rai == NULL) { 1677 syslog(LOG_DEBUG, "<%s> rainfo is NULL on %s." 1678 "Skip sending RAs.", 1679 __func__, ifi->ifi_ifname); 1680 return; 1681 } 1682 if (!(ifi->ifi_flags & IFF_UP)) { 1683 syslog(LOG_DEBUG, "<%s> %s is not up. " 1684 "Skip sending RAs.", 1685 __func__, ifi->ifi_ifname); 1686 return; 1687 } 1688 /* 1689 * Check lifetime, ACCEPT_RTADV flag, and ip6.forwarding. 1690 * 1691 * (lifetime == 0) = output 1692 * (lifetime != 0 && (check_accept_rtadv()) = no output 1693 * 1694 * Basically, hosts MUST NOT send Router Advertisement 1695 * messages at any time (RFC 4861, Section 6.2.3). However, it 1696 * would sometimes be useful to allow hosts to advertise some 1697 * parameters such as prefix information and link MTU. Thus, 1698 * we allow hosts to invoke rtadvd only when router lifetime 1699 * (on every advertising interface) is explicitly set 1700 * zero. (see also the above section) 1701 */ 1702 syslog(LOG_DEBUG, 1703 "<%s> check lifetime=%d, ACCEPT_RTADV=%d, ip6.forwarding=%d " 1704 "on %s", __func__, 1705 rai->rai_lifetime, 1706 check_accept_rtadv(ifi->ifi_ifindex), 1707 getinet6sysctl(IPV6CTL_FORWARDING), 1708 ifi->ifi_ifname); 1709 1710 if (rai->rai_lifetime != 0) { 1711 if (getinet6sysctl(IPV6CTL_FORWARDING) == 0) { 1712 syslog(LOG_ERR, 1713 "non-zero lifetime RA " 1714 "but net.inet6.ip6.forwarding=0. " 1715 "Ignored."); 1716 return; 1717 } 1718 if (check_accept_rtadv(ifi->ifi_ifindex)) { 1719 syslog(LOG_ERR, 1720 "non-zero lifetime RA " 1721 "on RA receiving interface %s." 1722 " Ignored.", ifi->ifi_ifname); 1723 return; 1724 } 1725 } 1726 1727 make_packet(rai); /* XXX: inefficient */ 1728 1729 sndmhdr.msg_name = (caddr_t)&sin6_linklocal_allnodes; 1730 sndmhdr.msg_iov[0].iov_base = (caddr_t)rai->rai_ra_data; 1731 sndmhdr.msg_iov[0].iov_len = rai->rai_ra_datalen; 1732 1733 cm = CMSG_FIRSTHDR(&sndmhdr); 1734 /* specify the outgoing interface */ 1735 cm->cmsg_level = IPPROTO_IPV6; 1736 cm->cmsg_type = IPV6_PKTINFO; 1737 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); 1738 pi = (struct in6_pktinfo *)CMSG_DATA(cm); 1739 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/ 1740 pi->ipi6_ifindex = ifi->ifi_ifindex; 1741 1742 /* specify the hop limit of the packet */ 1743 { 1744 int hoplimit = 255; 1745 1746 cm = CMSG_NXTHDR(&sndmhdr, cm); 1747 cm->cmsg_level = IPPROTO_IPV6; 1748 cm->cmsg_type = IPV6_HOPLIMIT; 1749 cm->cmsg_len = CMSG_LEN(sizeof(int)); 1750 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int)); 1751 } 1752 1753 syslog(LOG_DEBUG, 1754 "<%s> send RA on %s, # of RS waitings = %d", 1755 __func__, ifi->ifi_ifname, ifi->ifi_rs_waitcount); 1756 1757 i = sendmsg(sock.si_fd, &sndmhdr, 0); 1758 1759 if (i < 0 || (size_t)i != rai->rai_ra_datalen) { 1760 if (i < 0) { 1761 syslog(LOG_ERR, "<%s> sendmsg on %s: %s", 1762 __func__, ifi->ifi_ifname, 1763 strerror(errno)); 1764 } 1765 } 1766 1767 /* 1768 * unicast advertisements 1769 * XXX commented out. reason: though spec does not forbit it, unicast 1770 * advert does not really help 1771 */ 1772 while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) { 1773 TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next); 1774 free(sol); 1775 } 1776 1777 /* update timestamp */ 1778 clock_gettime(CLOCK_MONOTONIC_FAST, &ifi->ifi_ra_lastsent); 1779 1780 /* update counter */ 1781 ifi->ifi_rs_waitcount = 0; 1782 ifi->ifi_raoutput++; 1783 1784 switch (ifi->ifi_state) { 1785 case IFI_STATE_CONFIGURED: 1786 if (ifi->ifi_burstcount > 0) 1787 ifi->ifi_burstcount--; 1788 break; 1789 case IFI_STATE_TRANSITIVE: 1790 ifi->ifi_burstcount--; 1791 if (ifi->ifi_burstcount == 0) { 1792 if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) { 1793 /* Initial burst finished. */ 1794 if (ifi->ifi_rainfo_trans != NULL) 1795 ifi->ifi_rainfo_trans = NULL; 1796 } 1797 1798 /* Remove burst RA information */ 1799 if (ifi->ifi_rainfo_trans != NULL) { 1800 rm_rainfo(ifi->ifi_rainfo_trans); 1801 ifi->ifi_rainfo_trans = NULL; 1802 } 1803 1804 if (ifi->ifi_rainfo != NULL) { 1805 /* 1806 * TRANSITIVE -> CONFIGURED 1807 * 1808 * After initial burst or transition from 1809 * one configuration to another, 1810 * ifi_rainfo always points to the next RA 1811 * information. 1812 */ 1813 ifi->ifi_state = IFI_STATE_CONFIGURED; 1814 syslog(LOG_DEBUG, 1815 "<%s> ifname=%s marked as " 1816 "CONFIGURED.", __func__, 1817 ifi->ifi_ifname); 1818 } else { 1819 /* 1820 * TRANSITIVE -> UNCONFIGURED 1821 * 1822 * If ifi_rainfo points to NULL, this 1823 * interface is shutting down. 1824 * 1825 */ 1826 int error; 1827 1828 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 1829 syslog(LOG_DEBUG, 1830 "<%s> ifname=%s marked as " 1831 "UNCONFIGURED.", __func__, 1832 ifi->ifi_ifname); 1833 error = sock_mc_leave(&sock, 1834 ifi->ifi_ifindex); 1835 if (error) 1836 exit(1); 1837 } 1838 } 1839 break; 1840 } 1841 } 1842 1843 /* process RA timer */ 1844 struct rtadvd_timer * 1845 ra_timeout(void *arg) 1846 { 1847 struct ifinfo *ifi; 1848 1849 ifi = (struct ifinfo *)arg; 1850 syslog(LOG_DEBUG, "<%s> RA timer on %s is expired", 1851 __func__, ifi->ifi_ifname); 1852 1853 ra_output(ifi); 1854 1855 return (ifi->ifi_ra_timer); 1856 } 1857 1858 /* update RA timer */ 1859 void 1860 ra_timer_update(void *arg, struct timespec *tm) 1861 { 1862 uint16_t interval; 1863 struct rainfo *rai; 1864 struct ifinfo *ifi; 1865 1866 ifi = (struct ifinfo *)arg; 1867 rai = ifi->ifi_rainfo; 1868 interval = 0; 1869 1870 switch (ifi->ifi_state) { 1871 case IFI_STATE_UNCONFIGURED: 1872 return; 1873 break; 1874 case IFI_STATE_CONFIGURED: 1875 /* 1876 * Whenever a multicast advertisement is sent from 1877 * an interface, the timer is reset to a 1878 * uniformly-distributed random value between the 1879 * interface's configured MinRtrAdvInterval and 1880 * MaxRtrAdvInterval (RFC4861 6.2.4). 1881 */ 1882 interval = rai->rai_mininterval; 1883 #ifdef HAVE_ARC4RANDOM 1884 interval += arc4random_uniform(rai->rai_maxinterval - 1885 rai->rai_mininterval); 1886 #else 1887 interval += random() % (rai->rai_maxinterval - 1888 rai->rai_mininterval); 1889 #endif 1890 break; 1891 case IFI_STATE_TRANSITIVE: 1892 /* 1893 * For the first few advertisements (up to 1894 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen 1895 * interval is greater than 1896 * MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer SHOULD be 1897 * set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. (RFC 1898 * 4861 6.2.4) 1899 * 1900 * In such cases, the router SHOULD transmit one or more 1901 * (but not more than MAX_FINAL_RTR_ADVERTISEMENTS) final 1902 * multicast Router Advertisements on the interface with a 1903 * Router Lifetime field of zero. (RFC 4861 6.2.5) 1904 */ 1905 interval = ifi->ifi_burstinterval; 1906 break; 1907 } 1908 1909 tm->tv_sec = interval; 1910 tm->tv_nsec = 0; 1911 1912 syslog(LOG_DEBUG, 1913 "<%s> RA timer on %s is set to %ld:%ld", 1914 __func__, ifi->ifi_ifname, 1915 (long int)tm->tv_sec, (long int)tm->tv_nsec / 1000); 1916 1917 return; 1918 } 1919