1 /* $KAME: rtadvd.c,v 1.82 2003/08/05 12:34:23 itojun Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org> 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the project nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/param.h> 36 #include <sys/ioctl.h> 37 #include <sys/socket.h> 38 #include <sys/uio.h> 39 #include <sys/queue.h> 40 #include <sys/stat.h> 41 #include <sys/sysctl.h> 42 43 #include <net/if.h> 44 #include <net/if_types.h> 45 #include <net/if_media.h> 46 #include <net/if_dl.h> 47 #include <net/route.h> 48 #include <netinet/in.h> 49 #include <netinet/ip6.h> 50 #include <netinet6/ip6_var.h> 51 #include <netinet/icmp6.h> 52 53 #include <arpa/inet.h> 54 55 #include <netinet/in_var.h> 56 #include <netinet6/nd6.h> 57 58 #include <time.h> 59 #include <unistd.h> 60 #include <stdio.h> 61 #include <err.h> 62 #include <errno.h> 63 #include <inttypes.h> 64 #include <libutil.h> 65 #include <netdb.h> 66 #include <signal.h> 67 #include <string.h> 68 #include <stdlib.h> 69 #include <syslog.h> 70 #include <poll.h> 71 72 #include "pathnames.h" 73 #include "rtadvd.h" 74 #include "if.h" 75 #include "rrenum.h" 76 #include "advcap.h" 77 #include "timer_subr.h" 78 #include "timer.h" 79 #include "config.h" 80 #include "control.h" 81 #include "control_server.h" 82 83 #define RTADV_TYPE2BITMASK(type) (0x1 << type) 84 85 struct msghdr rcvmhdr; 86 static char *rcvcmsgbuf; 87 static size_t rcvcmsgbuflen; 88 static char *sndcmsgbuf = NULL; 89 static size_t sndcmsgbuflen; 90 struct msghdr sndmhdr; 91 struct iovec rcviov[2]; 92 struct iovec sndiov[2]; 93 struct sockaddr_in6 rcvfrom; 94 static const char *pidfilename = _PATH_RTADVDPID; 95 const char *conffile = _PATH_RTADVDCONF; 96 static struct pidfh *pfh; 97 static int dflag, sflag; 98 static int wait_shutdown; 99 100 #define PFD_RAWSOCK 0 101 #define PFD_RTSOCK 1 102 #define PFD_CSOCK 2 103 #define PFD_MAX 3 104 105 struct railist_head_t railist = 106 TAILQ_HEAD_INITIALIZER(railist); 107 struct ifilist_head_t ifilist = 108 TAILQ_HEAD_INITIALIZER(ifilist); 109 110 struct nd_optlist { 111 TAILQ_ENTRY(nd_optlist) nol_next; 112 struct nd_opt_hdr *nol_opt; 113 }; 114 union nd_opt { 115 struct nd_opt_hdr *opt_array[9]; 116 struct { 117 struct nd_opt_hdr *zero; 118 struct nd_opt_hdr *src_lladdr; 119 struct nd_opt_hdr *tgt_lladdr; 120 struct nd_opt_prefix_info *pi; 121 struct nd_opt_rd_hdr *rh; 122 struct nd_opt_mtu *mtu; 123 TAILQ_HEAD(, nd_optlist) opt_list; 124 } nd_opt_each; 125 }; 126 #define opt_src_lladdr nd_opt_each.src_lladdr 127 #define opt_tgt_lladdr nd_opt_each.tgt_lladdr 128 #define opt_pi nd_opt_each.pi 129 #define opt_rh nd_opt_each.rh 130 #define opt_mtu nd_opt_each.mtu 131 #define opt_list nd_opt_each.opt_list 132 133 #define NDOPT_FLAG_SRCLINKADDR (1 << 0) 134 #define NDOPT_FLAG_TGTLINKADDR (1 << 1) 135 #define NDOPT_FLAG_PREFIXINFO (1 << 2) 136 #define NDOPT_FLAG_RDHDR (1 << 3) 137 #define NDOPT_FLAG_MTU (1 << 4) 138 #define NDOPT_FLAG_RDNSS (1 << 5) 139 #define NDOPT_FLAG_DNSSL (1 << 6) 140 141 static uint32_t ndopt_flags[] = { 142 [ND_OPT_SOURCE_LINKADDR] = NDOPT_FLAG_SRCLINKADDR, 143 [ND_OPT_TARGET_LINKADDR] = NDOPT_FLAG_TGTLINKADDR, 144 [ND_OPT_PREFIX_INFORMATION] = NDOPT_FLAG_PREFIXINFO, 145 [ND_OPT_REDIRECTED_HEADER] = NDOPT_FLAG_RDHDR, 146 [ND_OPT_MTU] = NDOPT_FLAG_MTU, 147 [ND_OPT_RDNSS] = NDOPT_FLAG_RDNSS, 148 [ND_OPT_DNSSL] = NDOPT_FLAG_DNSSL, 149 }; 150 151 static void rtadvd_shutdown(void); 152 static void sock_open(struct sockinfo *); 153 static void rtsock_open(struct sockinfo *); 154 static void rtadvd_input(struct sockinfo *); 155 static void rs_input(int, struct nd_router_solicit *, 156 struct in6_pktinfo *, struct sockaddr_in6 *); 157 static void ra_input(int, struct nd_router_advert *, 158 struct in6_pktinfo *, struct sockaddr_in6 *); 159 static int prefix_check(struct nd_opt_prefix_info *, struct rainfo *, 160 struct sockaddr_in6 *); 161 static int nd6_options(struct nd_opt_hdr *, int, 162 union nd_opt *, uint32_t); 163 static void free_ndopts(union nd_opt *); 164 static void rtmsg_input(struct sockinfo *); 165 static void set_short_delay(struct ifinfo *); 166 static int check_accept_rtadv(int); 167 168 static void 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 pid, otherpid; 186 187 /* get command line options and arguments */ 188 while ((ch = getopt(argc, argv, "c:C:dDfhM:p:Rs")) != -1) { 189 switch (ch) { 190 case 'c': 191 conffile = optarg; 192 break; 193 case 'C': 194 ctrlsock.si_name = optarg; 195 break; 196 case 'd': 197 dflag++; 198 break; 199 case 'D': 200 dflag += 3; 201 break; 202 case 'f': 203 fflag = 1; 204 break; 205 case 'M': 206 mcastif = optarg; 207 break; 208 case 'R': 209 fprintf(stderr, "rtadvd: " 210 "the -R option is currently ignored.\n"); 211 /* accept_rr = 1; */ 212 /* run anyway... */ 213 break; 214 case 's': 215 sflag = 1; 216 break; 217 case 'p': 218 pidfilename = optarg; 219 break; 220 default: 221 usage(); 222 } 223 } 224 argc -= optind; 225 argv += optind; 226 227 logopt = LOG_NDELAY | LOG_PID; 228 if (fflag) 229 logopt |= LOG_PERROR; 230 openlog("rtadvd", logopt, LOG_DAEMON); 231 232 /* set log level */ 233 if (dflag > 2) 234 (void)setlogmask(LOG_UPTO(LOG_DEBUG)); 235 else if (dflag > 1) 236 (void)setlogmask(LOG_UPTO(LOG_INFO)); 237 else if (dflag > 0) 238 (void)setlogmask(LOG_UPTO(LOG_NOTICE)); 239 else 240 (void)setlogmask(LOG_UPTO(LOG_ERR)); 241 242 /* timer initialization */ 243 rtadvd_timer_init(); 244 245 pfh = pidfile_open(pidfilename, 0600, &otherpid); 246 if (pfh == NULL) { 247 if (errno == EEXIST) 248 errx(1, "%s already running, pid: %d", 249 getprogname(), otherpid); 250 syslog(LOG_ERR, 251 "failed to open the pid file %s, run anyway.", 252 pidfilename); 253 } 254 if (!fflag) 255 daemon(1, 0); 256 257 sock_open(&sock); 258 259 update_ifinfo(&ifilist, UPDATE_IFINFO_ALL); 260 for (i = 0; i < argc; i++) 261 update_persist_ifinfo(&ifilist, argv[i]); 262 263 csock_open(&ctrlsock, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH); 264 if (ctrlsock.si_fd == -1) { 265 syslog(LOG_ERR, "cannot open control socket: %s", 266 strerror(errno)); 267 exit(1); 268 } 269 270 /* record the current PID */ 271 pid = getpid(); 272 pidfile_write(pfh); 273 274 set[PFD_RAWSOCK].fd = sock.si_fd; 275 set[PFD_RAWSOCK].events = POLLIN; 276 if (sflag == 0) { 277 rtsock_open(&rtsock); 278 set[PFD_RTSOCK].fd = rtsock.si_fd; 279 set[PFD_RTSOCK].events = POLLIN; 280 } else 281 set[PFD_RTSOCK].fd = -1; 282 set[PFD_CSOCK].fd = ctrlsock.si_fd; 283 set[PFD_CSOCK].events = POLLIN; 284 signal(SIGTERM, set_do_shutdown); 285 signal(SIGINT, set_do_shutdown); 286 signal(SIGHUP, set_do_reload); 287 288 error = csock_listen(&ctrlsock); 289 if (error) { 290 syslog(LOG_ERR, "cannot listen control socket: %s", 291 strerror(errno)); 292 exit(1); 293 } 294 295 /* load configuration file */ 296 set_do_reload(0); 297 298 while (1) { 299 if (is_do_shutdown()) 300 rtadvd_shutdown(); 301 302 if (is_do_reload()) { 303 loadconfig_ifname(reload_ifname()); 304 if (reload_ifname() == NULL) 305 syslog(LOG_INFO, 306 "configuration file reloaded."); 307 else 308 syslog(LOG_INFO, 309 "configuration file for %s reloaded.", 310 reload_ifname()); 311 reset_do_reload(); 312 } 313 314 /* timeout handler update for active interfaces */ 315 rtadvd_update_timeout_handler(); 316 317 /* timer expiration check and reset the timer */ 318 timeout = rtadvd_check_timer(); 319 320 if (timeout != NULL) { 321 syslog(LOG_DEBUG, 322 "<%s> set timer to %ld:%ld. waiting for " 323 "inputs or timeout", __func__, 324 (long int)timeout->tv_sec, 325 (long int)timeout->tv_nsec / 1000); 326 } else { 327 syslog(LOG_DEBUG, 328 "<%s> there's no timer. waiting for inputs", 329 __func__); 330 } 331 if ((i = poll(set, sizeof(set)/sizeof(set[0]), 332 timeout ? (timeout->tv_sec * 1000 + 333 timeout->tv_nsec / 1000 / 1000) : INFTIM)) < 0) { 334 335 /* EINTR would occur if a signal was delivered */ 336 if (errno != EINTR) 337 syslog(LOG_ERR, "poll() failed: %s", 338 strerror(errno)); 339 continue; 340 } 341 if (i == 0) /* timeout */ 342 continue; 343 if (rtsock.si_fd != -1 && set[PFD_RTSOCK].revents & POLLIN) 344 rtmsg_input(&rtsock); 345 346 if (set[PFD_RAWSOCK].revents & POLLIN) 347 rtadvd_input(&sock); 348 349 if (set[PFD_CSOCK].revents & POLLIN) { 350 int fd; 351 352 fd = csock_accept(&ctrlsock); 353 if (fd == -1) 354 syslog(LOG_ERR, 355 "cannot accept() control socket: %s", 356 strerror(errno)); 357 else { 358 cm_handler_server(fd); 359 close(fd); 360 } 361 } 362 } 363 exit(0); /* NOTREACHED */ 364 } 365 366 static void 367 rtadvd_shutdown(void) 368 { 369 struct ifinfo *ifi; 370 struct rainfo *rai; 371 struct rdnss *rdn; 372 struct dnssl *dns; 373 374 if (wait_shutdown) { 375 syslog(LOG_INFO, 376 "waiting expiration of the all RA timers."); 377 378 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 379 /* 380 * Ignore !IFF_UP interfaces in waiting for shutdown. 381 */ 382 if (!(ifi->ifi_flags & IFF_UP) && 383 ifi->ifi_ra_timer != NULL) { 384 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 385 rtadvd_remove_timer(ifi->ifi_ra_timer); 386 ifi->ifi_ra_timer = NULL; 387 syslog(LOG_DEBUG, "<%s> %s(idx=%d) is down. " 388 "Timer removed and marked as UNCONFIGURED.", 389 __func__, ifi->ifi_ifname, 390 ifi->ifi_ifindex); 391 } 392 } 393 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 394 if (ifi->ifi_ra_timer != NULL) 395 break; 396 } 397 if (ifi == NULL) { 398 syslog(LOG_NOTICE, "gracefully terminated."); 399 exit(0); 400 } 401 402 sleep(1); 403 return; 404 } 405 406 syslog(LOG_DEBUG, "<%s> cease to be an advertising router", 407 __func__); 408 409 wait_shutdown = 1; 410 411 TAILQ_FOREACH(rai, &railist, rai_next) { 412 rai->rai_lifetime = 0; 413 TAILQ_FOREACH(rdn, &rai->rai_rdnss, rd_next) 414 rdn->rd_ltime = 0; 415 TAILQ_FOREACH(dns, &rai->rai_dnssl, dn_next) 416 dns->dn_ltime = 0; 417 } 418 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 419 if (!ifi->ifi_persist) 420 continue; 421 if (ifi->ifi_state == IFI_STATE_UNCONFIGURED) 422 continue; 423 if (ifi->ifi_ra_timer == NULL) 424 continue; 425 if (ifi->ifi_ra_lastsent.tv_sec == 0 && 426 ifi->ifi_ra_lastsent.tv_nsec == 0 && 427 ifi->ifi_ra_timer != NULL) { 428 /* 429 * When RA configured but never sent, 430 * ignore the IF immediately. 431 */ 432 rtadvd_remove_timer(ifi->ifi_ra_timer); 433 ifi->ifi_ra_timer = NULL; 434 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 435 continue; 436 } 437 438 ifi->ifi_state = IFI_STATE_TRANSITIVE; 439 440 /* Mark as the shut-down state. */ 441 ifi->ifi_rainfo_trans = ifi->ifi_rainfo; 442 ifi->ifi_rainfo = NULL; 443 444 ifi->ifi_burstcount = MAX_FINAL_RTR_ADVERTISEMENTS; 445 ifi->ifi_burstinterval = MIN_DELAY_BETWEEN_RAS; 446 447 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm); 448 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm, 449 ifi->ifi_ra_timer); 450 } 451 syslog(LOG_NOTICE, "final RA transmission started."); 452 453 pidfile_remove(pfh); 454 csock_close(&ctrlsock); 455 } 456 457 static void 458 rtmsg_input(struct sockinfo *s) 459 { 460 int n, type, ifindex = 0, plen; 461 size_t len; 462 char msg[2048], *next, *lim; 463 char ifname[IFNAMSIZ]; 464 struct if_announcemsghdr *ifan; 465 struct rt_msghdr *rtm; 466 struct prefix *pfx; 467 struct rainfo *rai; 468 struct in6_addr *addr; 469 struct ifinfo *ifi; 470 char addrbuf[INET6_ADDRSTRLEN]; 471 int prefixchange = 0; 472 473 if (s == NULL) { 474 syslog(LOG_ERR, "<%s> internal error", __func__); 475 exit(1); 476 } 477 n = read(s->si_fd, msg, sizeof(msg)); 478 rtm = (struct rt_msghdr *)msg; 479 syslog(LOG_DEBUG, "<%s> received a routing message " 480 "(type = %d, len = %d)", __func__, rtm->rtm_type, n); 481 482 if (n > rtm->rtm_msglen) { 483 /* 484 * This usually won't happen for messages received on 485 * a routing socket. 486 */ 487 syslog(LOG_DEBUG, 488 "<%s> received data length is larger than " 489 "1st routing message len. multiple messages? " 490 "read %d bytes, but 1st msg len = %d", 491 __func__, n, rtm->rtm_msglen); 492 #if 0 493 /* adjust length */ 494 n = rtm->rtm_msglen; 495 #endif 496 } 497 498 lim = msg + n; 499 for (next = msg; next < lim; next += len) { 500 int oldifflags; 501 502 next = get_next_msg(next, lim, 0, &len, 503 RTADV_TYPE2BITMASK(RTM_ADD) | 504 RTADV_TYPE2BITMASK(RTM_DELETE) | 505 RTADV_TYPE2BITMASK(RTM_NEWADDR) | 506 RTADV_TYPE2BITMASK(RTM_DELADDR) | 507 RTADV_TYPE2BITMASK(RTM_IFINFO) | 508 RTADV_TYPE2BITMASK(RTM_IFANNOUNCE)); 509 if (len == 0) 510 break; 511 type = ((struct rt_msghdr *)next)->rtm_type; 512 switch (type) { 513 case RTM_ADD: 514 case RTM_DELETE: 515 ifindex = get_rtm_ifindex(next); 516 break; 517 case RTM_NEWADDR: 518 case RTM_DELADDR: 519 ifindex = (int)((struct ifa_msghdr *)next)->ifam_index; 520 break; 521 case RTM_IFINFO: 522 ifindex = (int)((struct if_msghdr *)next)->ifm_index; 523 break; 524 case RTM_IFANNOUNCE: 525 ifan = (struct if_announcemsghdr *)next; 526 switch (ifan->ifan_what) { 527 case IFAN_ARRIVAL: 528 case IFAN_DEPARTURE: 529 break; 530 default: 531 syslog(LOG_DEBUG, 532 "<%s:%d> unknown ifan msg (ifan_what=%d)", 533 __func__, __LINE__, ifan->ifan_what); 534 continue; 535 } 536 537 syslog(LOG_DEBUG, "<%s>: if_announcemsg (idx=%d:%d)", 538 __func__, ifan->ifan_index, ifan->ifan_what); 539 switch (ifan->ifan_what) { 540 case IFAN_ARRIVAL: 541 syslog(LOG_NOTICE, 542 "interface added (idx=%d)", 543 ifan->ifan_index); 544 update_ifinfo(&ifilist, ifan->ifan_index); 545 loadconfig_index(ifan->ifan_index); 546 break; 547 case IFAN_DEPARTURE: 548 syslog(LOG_NOTICE, 549 "interface removed (idx=%d)", 550 ifan->ifan_index); 551 rm_ifinfo_index(ifan->ifan_index); 552 553 /* Clear ifi_ifindex */ 554 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 555 if (ifi->ifi_ifindex 556 == ifan->ifan_index) { 557 ifi->ifi_ifindex = 0; 558 break; 559 } 560 } 561 update_ifinfo(&ifilist, ifan->ifan_index); 562 break; 563 } 564 continue; 565 default: 566 /* should not reach here */ 567 syslog(LOG_DEBUG, 568 "<%s:%d> unknown rtmsg %d on %s", 569 __func__, __LINE__, type, 570 if_indextoname(ifindex, ifname)); 571 continue; 572 } 573 ifi = if_indextoifinfo(ifindex); 574 if (ifi == NULL) { 575 syslog(LOG_DEBUG, 576 "<%s> ifinfo not found for idx=%d. Why?", 577 __func__, ifindex); 578 continue; 579 } 580 rai = ifi->ifi_rainfo; 581 if (rai == NULL) { 582 syslog(LOG_DEBUG, 583 "<%s> route changed on " 584 "non advertising interface(%s)", 585 __func__, ifi->ifi_ifname); 586 continue; 587 } 588 589 oldifflags = ifi->ifi_flags; 590 /* init ifflags because it may have changed */ 591 update_ifinfo(&ifilist, ifindex); 592 593 switch (type) { 594 case RTM_ADD: 595 if (sflag) 596 break; /* we aren't interested in prefixes */ 597 598 addr = get_addr(msg); 599 plen = get_prefixlen(msg); 600 /* sanity check for plen */ 601 /* as RFC2373, prefixlen is at least 4 */ 602 if (plen < 4 || plen > 127) { 603 syslog(LOG_INFO, "<%s> new interface route's" 604 "plen %d is invalid for a prefix", 605 __func__, plen); 606 break; 607 } 608 pfx = find_prefix(rai, addr, plen); 609 if (pfx) { 610 if (pfx->pfx_timer) { 611 /* 612 * If the prefix has been invalidated, 613 * make it available again. 614 */ 615 update_prefix(pfx); 616 prefixchange = 1; 617 } else 618 syslog(LOG_DEBUG, 619 "<%s> new prefix(%s/%d) " 620 "added on %s, " 621 "but it was already in list", 622 __func__, 623 inet_ntop(AF_INET6, addr, 624 (char *)addrbuf, 625 sizeof(addrbuf)), 626 plen, ifi->ifi_ifname); 627 break; 628 } 629 make_prefix(rai, ifindex, addr, plen); 630 prefixchange = 1; 631 break; 632 case RTM_DELETE: 633 if (sflag) 634 break; 635 636 addr = get_addr(msg); 637 plen = get_prefixlen(msg); 638 /* sanity check for plen */ 639 /* as RFC2373, prefixlen is at least 4 */ 640 if (plen < 4 || plen > 127) { 641 syslog(LOG_INFO, 642 "<%s> deleted interface route's " 643 "plen %d is invalid for a prefix", 644 __func__, plen); 645 break; 646 } 647 pfx = find_prefix(rai, addr, plen); 648 if (pfx == NULL) { 649 syslog(LOG_DEBUG, 650 "<%s> prefix(%s/%d) was deleted on %s, " 651 "but it was not in list", 652 __func__, inet_ntop(AF_INET6, addr, 653 (char *)addrbuf, sizeof(addrbuf)), 654 plen, ifi->ifi_ifname); 655 break; 656 } 657 invalidate_prefix(pfx); 658 prefixchange = 1; 659 break; 660 case RTM_NEWADDR: 661 case RTM_DELADDR: 662 case RTM_IFINFO: 663 break; 664 default: 665 /* should not reach here */ 666 syslog(LOG_DEBUG, 667 "<%s:%d> unknown rtmsg %d on %s", 668 __func__, __LINE__, type, 669 if_indextoname(ifindex, ifname)); 670 return; 671 } 672 673 /* check if an interface flag is changed */ 674 if ((oldifflags & IFF_UP) && /* UP to DOWN */ 675 !(ifi->ifi_flags & IFF_UP)) { 676 syslog(LOG_NOTICE, 677 "<interface %s becomes down. stop timer.", 678 ifi->ifi_ifname); 679 rtadvd_remove_timer(ifi->ifi_ra_timer); 680 ifi->ifi_ra_timer = NULL; 681 } else if (!(oldifflags & IFF_UP) && /* DOWN to UP */ 682 (ifi->ifi_flags & IFF_UP)) { 683 syslog(LOG_NOTICE, 684 "interface %s becomes up. restart timer.", 685 ifi->ifi_ifname); 686 687 ifi->ifi_state = IFI_STATE_TRANSITIVE; 688 ifi->ifi_burstcount = 689 MAX_INITIAL_RTR_ADVERTISEMENTS; 690 ifi->ifi_burstinterval = 691 MAX_INITIAL_RTR_ADVERT_INTERVAL; 692 693 ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout, 694 ra_timer_update, ifi, ifi); 695 ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm); 696 rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm, 697 ifi->ifi_ra_timer); 698 } else if (prefixchange && 699 (ifi->ifi_flags & IFF_UP)) { 700 /* 701 * An advertised prefix has been added or invalidated. 702 * Will notice the change in a short delay. 703 */ 704 set_short_delay(ifi); 705 } 706 } 707 708 return; 709 } 710 711 void 712 rtadvd_input(struct sockinfo *s) 713 { 714 ssize_t i; 715 int *hlimp = NULL; 716 #ifdef OLDRAWSOCKET 717 struct ip6_hdr *ip; 718 #endif 719 struct icmp6_hdr *icp; 720 int ifindex = 0; 721 struct cmsghdr *cm; 722 struct in6_pktinfo *pi = NULL; 723 char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; 724 struct in6_addr dst = in6addr_any; 725 struct ifinfo *ifi; 726 727 syslog(LOG_DEBUG, "<%s> enter", __func__); 728 729 if (s == NULL) { 730 syslog(LOG_ERR, "<%s> internal error", __func__); 731 exit(1); 732 } 733 /* 734 * Get message. We reset msg_controllen since the field could 735 * be modified if we had received a message before setting 736 * receive options. 737 */ 738 rcvmhdr.msg_controllen = rcvcmsgbuflen; 739 if ((i = recvmsg(s->si_fd, &rcvmhdr, 0)) < 0) 740 return; 741 742 /* extract optional information via Advanced API */ 743 for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr); 744 cm; 745 cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) { 746 if (cm->cmsg_level == IPPROTO_IPV6 && 747 cm->cmsg_type == IPV6_PKTINFO && 748 cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) { 749 pi = (struct in6_pktinfo *)(CMSG_DATA(cm)); 750 ifindex = pi->ipi6_ifindex; 751 dst = pi->ipi6_addr; 752 } 753 if (cm->cmsg_level == IPPROTO_IPV6 && 754 cm->cmsg_type == IPV6_HOPLIMIT && 755 cm->cmsg_len == CMSG_LEN(sizeof(int))) 756 hlimp = (int *)CMSG_DATA(cm); 757 } 758 if (ifindex == 0) { 759 syslog(LOG_ERR, "failed to get receiving interface"); 760 return; 761 } 762 if (hlimp == NULL) { 763 syslog(LOG_ERR, "failed to get receiving hop limit"); 764 return; 765 } 766 767 /* 768 * If we happen to receive data on an interface which is now gone 769 * or down, just discard the data. 770 */ 771 ifi = if_indextoifinfo(pi->ipi6_ifindex); 772 if (ifi == NULL || !(ifi->ifi_flags & IFF_UP)) { 773 syslog(LOG_INFO, 774 "<%s> received data on a disabled interface (%s)", 775 __func__, 776 (ifi == NULL) ? "[gone]" : ifi->ifi_ifname); 777 return; 778 } 779 780 #ifdef OLDRAWSOCKET 781 if ((size_t)i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) { 782 syslog(LOG_ERR, 783 "packet size(%d) is too short", i); 784 return; 785 } 786 787 ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base; 788 icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */ 789 #else 790 if ((size_t)i < sizeof(struct icmp6_hdr)) { 791 syslog(LOG_ERR, "packet size(%zd) is too short", i); 792 return; 793 } 794 795 icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base; 796 #endif 797 798 switch (icp->icmp6_type) { 799 case ND_ROUTER_SOLICIT: 800 /* 801 * Message verification - RFC 4861 6.1.1 802 * XXX: these checks must be done in the kernel as well, 803 * but we can't completely rely on them. 804 */ 805 if (*hlimp != 255) { 806 syslog(LOG_NOTICE, 807 "RS with invalid hop limit(%d) " 808 "received from %s on %s", 809 *hlimp, 810 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 811 sizeof(ntopbuf)), 812 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 813 return; 814 } 815 if (icp->icmp6_code) { 816 syslog(LOG_NOTICE, 817 "RS with invalid ICMP6 code(%d) " 818 "received from %s on %s", 819 icp->icmp6_code, 820 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 821 sizeof(ntopbuf)), 822 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 823 return; 824 } 825 if ((size_t)i < sizeof(struct nd_router_solicit)) { 826 syslog(LOG_NOTICE, 827 "RS from %s on %s does not have enough " 828 "length (len = %zd)", 829 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 830 sizeof(ntopbuf)), 831 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 832 return; 833 } 834 rs_input(i, (struct nd_router_solicit *)icp, pi, &rcvfrom); 835 break; 836 case ND_ROUTER_ADVERT: 837 /* 838 * Message verification - RFC 4861 6.1.2 839 * XXX: there's the same dilemma as above... 840 */ 841 if (!IN6_IS_ADDR_LINKLOCAL(&rcvfrom.sin6_addr)) { 842 syslog(LOG_NOTICE, 843 "RA with non-linklocal source address " 844 "received from %s on %s", 845 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, 846 ntopbuf, sizeof(ntopbuf)), 847 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 848 return; 849 } 850 if (*hlimp != 255) { 851 syslog(LOG_NOTICE, 852 "RA with invalid hop limit(%d) " 853 "received from %s on %s", 854 *hlimp, 855 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 856 sizeof(ntopbuf)), 857 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 858 return; 859 } 860 if (icp->icmp6_code) { 861 syslog(LOG_NOTICE, 862 "RA with invalid ICMP6 code(%d) " 863 "received from %s on %s", 864 icp->icmp6_code, 865 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 866 sizeof(ntopbuf)), 867 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 868 return; 869 } 870 if ((size_t)i < sizeof(struct nd_router_advert)) { 871 syslog(LOG_NOTICE, 872 "RA from %s on %s does not have enough " 873 "length (len = %zd)", 874 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 875 sizeof(ntopbuf)), 876 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 877 return; 878 } 879 ra_input(i, (struct nd_router_advert *)icp, pi, &rcvfrom); 880 break; 881 case ICMP6_ROUTER_RENUMBERING: 882 if (mcastif == NULL) { 883 syslog(LOG_ERR, "received a router renumbering " 884 "message, but not allowed to be accepted"); 885 break; 886 } 887 rr_input(i, (struct icmp6_router_renum *)icp, pi, &rcvfrom, 888 &dst); 889 break; 890 default: 891 /* 892 * Note that this case is POSSIBLE, especially just 893 * after invocation of the daemon. This is because we 894 * could receive message after opening the socket and 895 * before setting ICMP6 type filter(see sock_open()). 896 */ 897 syslog(LOG_ERR, "invalid icmp type(%d)", icp->icmp6_type); 898 return; 899 } 900 901 return; 902 } 903 904 static void 905 rs_input(int len, struct nd_router_solicit *rs, 906 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 907 { 908 char ntopbuf[INET6_ADDRSTRLEN]; 909 char ifnamebuf[IFNAMSIZ]; 910 union nd_opt ndopts; 911 struct rainfo *rai; 912 struct ifinfo *ifi; 913 struct soliciter *sol; 914 915 syslog(LOG_DEBUG, 916 "<%s> RS received from %s on %s", 917 __func__, 918 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 919 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 920 921 /* ND option check */ 922 memset(&ndopts, 0, sizeof(ndopts)); 923 TAILQ_INIT(&ndopts.opt_list); 924 if (nd6_options((struct nd_opt_hdr *)(rs + 1), 925 len - sizeof(struct nd_router_solicit), 926 &ndopts, NDOPT_FLAG_SRCLINKADDR)) { 927 syslog(LOG_INFO, 928 "<%s> ND option check failed for an RS from %s on %s", 929 __func__, 930 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 931 sizeof(ntopbuf)), 932 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 933 return; 934 } 935 936 /* 937 * If the IP source address is the unspecified address, there 938 * must be no source link-layer address option in the message. 939 * (RFC 4861 6.1.1) 940 */ 941 if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) && 942 ndopts.opt_src_lladdr) { 943 syslog(LOG_INFO, 944 "<%s> RS from unspecified src on %s has a link-layer" 945 " address option", 946 __func__, if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 947 goto done; 948 } 949 950 ifi = if_indextoifinfo(pi->ipi6_ifindex); 951 if (ifi == NULL) { 952 syslog(LOG_INFO, 953 "<%s> if (idx=%d) not found. Why?", 954 __func__, pi->ipi6_ifindex); 955 goto done; 956 } 957 rai = ifi->ifi_rainfo; 958 if (rai == NULL) { 959 syslog(LOG_INFO, 960 "<%s> RS received on non advertising interface(%s)", 961 __func__, 962 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 963 goto done; 964 } 965 966 rai->rai_ifinfo->ifi_rsinput++; 967 968 /* 969 * Decide whether to send RA according to the rate-limit 970 * consideration. 971 */ 972 973 /* record sockaddr waiting for RA, if possible */ 974 sol = (struct soliciter *)malloc(sizeof(*sol)); 975 if (sol) { 976 sol->sol_addr = *from; 977 /* XXX RFC 2553 need clarification on flowinfo */ 978 sol->sol_addr.sin6_flowinfo = 0; 979 TAILQ_INSERT_TAIL(&rai->rai_soliciter, sol, sol_next); 980 } 981 982 /* 983 * If there is already a waiting RS packet, don't 984 * update the timer. 985 */ 986 if (ifi->ifi_rs_waitcount++) 987 goto done; 988 989 set_short_delay(ifi); 990 991 done: 992 free_ndopts(&ndopts); 993 return; 994 } 995 996 static void 997 set_short_delay(struct ifinfo *ifi) 998 { 999 long delay; /* must not be greater than 1000000 */ 1000 struct timespec interval, now, min_delay, tm_tmp, *rest; 1001 1002 if (ifi->ifi_ra_timer == NULL) 1003 return; 1004 /* 1005 * Compute a random delay. If the computed value 1006 * corresponds to a time later than the time the next 1007 * multicast RA is scheduled to be sent, ignore the random 1008 * delay and send the advertisement at the 1009 * already-scheduled time. RFC 4861 6.2.6 1010 */ 1011 delay = arc4random_uniform(MAX_RA_DELAY_TIME); 1012 interval.tv_sec = 0; 1013 interval.tv_nsec = delay * 1000; 1014 rest = rtadvd_timer_rest(ifi->ifi_ra_timer); 1015 if (TS_CMP(rest, &interval, <)) { 1016 syslog(LOG_DEBUG, "<%s> random delay is larger than " 1017 "the rest of the current timer", __func__); 1018 interval = *rest; 1019 } 1020 1021 /* 1022 * If we sent a multicast Router Advertisement within 1023 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule 1024 * the advertisement to be sent at a time corresponding to 1025 * MIN_DELAY_BETWEEN_RAS plus the random value after the 1026 * previous advertisement was sent. 1027 */ 1028 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1029 TS_SUB(&now, &ifi->ifi_ra_lastsent, &tm_tmp); 1030 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS; 1031 min_delay.tv_nsec = 0; 1032 if (TS_CMP(&tm_tmp, &min_delay, <)) { 1033 TS_SUB(&min_delay, &tm_tmp, &min_delay); 1034 TS_ADD(&min_delay, &interval, &interval); 1035 } 1036 rtadvd_set_timer(&interval, ifi->ifi_ra_timer); 1037 } 1038 1039 static int 1040 check_accept_rtadv(int idx) 1041 { 1042 struct ifinfo *ifi; 1043 1044 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1045 if (ifi->ifi_ifindex == idx) 1046 break; 1047 } 1048 if (ifi == NULL) { 1049 syslog(LOG_DEBUG, 1050 "<%s> if (idx=%d) not found. Why?", 1051 __func__, idx); 1052 return (0); 1053 } 1054 1055 /* 1056 * RA_RECV: ND6_IFF_ACCEPT_RTADV 1057 * RA_SEND: ip6.forwarding 1058 */ 1059 if (update_ifinfo_nd_flags(ifi) != 0) { 1060 syslog(LOG_ERR, "cannot get nd6 flags (idx=%d)", idx); 1061 return (0); 1062 } 1063 1064 return (ifi->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV); 1065 } 1066 1067 static void 1068 ra_input(int len, struct nd_router_advert *nra, 1069 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 1070 { 1071 struct rainfo *rai; 1072 struct ifinfo *ifi; 1073 char ntopbuf[INET6_ADDRSTRLEN]; 1074 char ifnamebuf[IFNAMSIZ]; 1075 union nd_opt ndopts; 1076 const char *on_off[] = {"OFF", "ON"}; 1077 uint32_t reachabletime, retranstimer, mtu; 1078 int inconsistent = 0; 1079 int error; 1080 1081 syslog(LOG_DEBUG, "<%s> RA received from %s on %s", __func__, 1082 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, sizeof(ntopbuf)), 1083 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 1084 1085 /* ND option check */ 1086 memset(&ndopts, 0, sizeof(ndopts)); 1087 TAILQ_INIT(&ndopts.opt_list); 1088 error = nd6_options((struct nd_opt_hdr *)(nra + 1), 1089 len - sizeof(struct nd_router_advert), &ndopts, 1090 NDOPT_FLAG_SRCLINKADDR | NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU | 1091 NDOPT_FLAG_RDNSS | NDOPT_FLAG_DNSSL); 1092 if (error) { 1093 syslog(LOG_INFO, 1094 "<%s> ND option check failed for an RA from %s on %s", 1095 __func__, 1096 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1097 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1098 ifnamebuf)); 1099 return; 1100 } 1101 1102 /* 1103 * RA consistency check according to RFC 4861 6.2.7 1104 */ 1105 ifi = if_indextoifinfo(pi->ipi6_ifindex); 1106 if (ifi->ifi_rainfo == NULL) { 1107 syslog(LOG_INFO, 1108 "<%s> received RA from %s on non-advertising" 1109 " interface(%s)", 1110 __func__, 1111 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1112 sizeof(ntopbuf)), if_indextoname(pi->ipi6_ifindex, 1113 ifnamebuf)); 1114 goto done; 1115 } 1116 rai = ifi->ifi_rainfo; 1117 ifi->ifi_rainput++; 1118 syslog(LOG_DEBUG, "<%s> ifi->ifi_rainput = %" PRIu64, __func__, 1119 ifi->ifi_rainput); 1120 1121 /* Cur Hop Limit value */ 1122 if (nra->nd_ra_curhoplimit && rai->rai_hoplimit && 1123 nra->nd_ra_curhoplimit != rai->rai_hoplimit) { 1124 syslog(LOG_NOTICE, 1125 "CurHopLimit inconsistent on %s:" 1126 " %d from %s, %d from us", 1127 ifi->ifi_ifname, nra->nd_ra_curhoplimit, 1128 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1129 sizeof(ntopbuf)), rai->rai_hoplimit); 1130 inconsistent++; 1131 } 1132 /* M flag */ 1133 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) != 1134 rai->rai_managedflg) { 1135 syslog(LOG_NOTICE, 1136 "M flag inconsistent on %s:" 1137 " %s from %s, %s from us", 1138 ifi->ifi_ifname, on_off[!rai->rai_managedflg], 1139 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1140 sizeof(ntopbuf)), on_off[rai->rai_managedflg]); 1141 inconsistent++; 1142 } 1143 /* O flag */ 1144 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) != 1145 rai->rai_otherflg) { 1146 syslog(LOG_NOTICE, 1147 "O flag inconsistent on %s:" 1148 " %s from %s, %s from us", 1149 ifi->ifi_ifname, on_off[!rai->rai_otherflg], 1150 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1151 sizeof(ntopbuf)), on_off[rai->rai_otherflg]); 1152 inconsistent++; 1153 } 1154 #ifdef DRAFT_IETF_6MAN_IPV6ONLY_FLAG 1155 /* S "IPv6-Only" (Six, Silence-IPv4) flag */ 1156 if ((nra->nd_ra_flags_reserved & ND_RA_FLAG_IPV6_ONLY) != 1157 rai->rai_ipv6onlyflg) { 1158 syslog(LOG_NOTICE, 1159 "S flag inconsistent on %s:" 1160 " %s from %s, %s from us", 1161 ifi->ifi_ifname, on_off[!rai->rai_ipv6onlyflg], 1162 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1163 sizeof(ntopbuf)), on_off[rai->rai_ipv6onlyflg]); 1164 inconsistent++; 1165 } 1166 #endif 1167 /* Reachable Time */ 1168 reachabletime = ntohl(nra->nd_ra_reachable); 1169 if (reachabletime && rai->rai_reachabletime && 1170 reachabletime != rai->rai_reachabletime) { 1171 syslog(LOG_NOTICE, 1172 "ReachableTime inconsistent on %s:" 1173 " %d from %s, %d from us", 1174 ifi->ifi_ifname, reachabletime, 1175 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1176 sizeof(ntopbuf)), rai->rai_reachabletime); 1177 inconsistent++; 1178 } 1179 /* Retrans Timer */ 1180 retranstimer = ntohl(nra->nd_ra_retransmit); 1181 if (retranstimer && rai->rai_retranstimer && 1182 retranstimer != rai->rai_retranstimer) { 1183 syslog(LOG_NOTICE, 1184 "RetranceTimer inconsistent on %s:" 1185 " %d from %s, %d from us", 1186 ifi->ifi_ifname, retranstimer, 1187 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1188 sizeof(ntopbuf)), rai->rai_retranstimer); 1189 inconsistent++; 1190 } 1191 /* Values in the MTU options */ 1192 if (ndopts.opt_mtu) { 1193 mtu = ntohl(ndopts.opt_mtu->nd_opt_mtu_mtu); 1194 if (mtu && rai->rai_linkmtu && mtu != rai->rai_linkmtu) { 1195 syslog(LOG_NOTICE, 1196 "MTU option value inconsistent on %s:" 1197 " %d from %s, %d from us", 1198 ifi->ifi_ifname, mtu, 1199 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1200 sizeof(ntopbuf)), rai->rai_linkmtu); 1201 inconsistent++; 1202 } 1203 } 1204 /* Preferred and Valid Lifetimes for prefixes */ 1205 { 1206 struct nd_optlist *nol; 1207 1208 if (ndopts.opt_pi) 1209 if (prefix_check(ndopts.opt_pi, rai, from)) 1210 inconsistent++; 1211 1212 TAILQ_FOREACH(nol, &ndopts.opt_list, nol_next) 1213 if (prefix_check((struct nd_opt_prefix_info *)nol->nol_opt, 1214 rai, from)) 1215 inconsistent++; 1216 } 1217 1218 if (inconsistent) 1219 ifi->ifi_rainconsistent++; 1220 1221 done: 1222 free_ndopts(&ndopts); 1223 return; 1224 } 1225 1226 static uint32_t 1227 udiff(uint32_t u, uint32_t v) 1228 { 1229 return (u >= v ? u - v : v - u); 1230 } 1231 1232 /* return a non-zero value if the received prefix is inconsistent with ours */ 1233 static int 1234 prefix_check(struct nd_opt_prefix_info *pinfo, 1235 struct rainfo *rai, struct sockaddr_in6 *from) 1236 { 1237 struct ifinfo *ifi; 1238 uint32_t preferred_time, valid_time; 1239 struct prefix *pfx; 1240 int inconsistent = 0; 1241 char ntopbuf[INET6_ADDRSTRLEN]; 1242 char prefixbuf[INET6_ADDRSTRLEN]; 1243 struct timespec now; 1244 1245 #if 0 /* impossible */ 1246 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION) 1247 return (0); 1248 #endif 1249 ifi = rai->rai_ifinfo; 1250 /* 1251 * log if the adveritsed prefix has link-local scope(sanity check?) 1252 */ 1253 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) 1254 syslog(LOG_INFO, 1255 "<%s> link-local prefix %s/%d is advertised " 1256 "from %s on %s", 1257 __func__, 1258 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1259 sizeof(prefixbuf)), 1260 pinfo->nd_opt_pi_prefix_len, 1261 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1262 sizeof(ntopbuf)), ifi->ifi_ifname); 1263 1264 if ((pfx = find_prefix(rai, &pinfo->nd_opt_pi_prefix, 1265 pinfo->nd_opt_pi_prefix_len)) == NULL) { 1266 syslog(LOG_INFO, 1267 "<%s> prefix %s/%d from %s on %s is not in our list", 1268 __func__, 1269 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1270 sizeof(prefixbuf)), 1271 pinfo->nd_opt_pi_prefix_len, 1272 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1273 sizeof(ntopbuf)), ifi->ifi_ifname); 1274 return (0); 1275 } 1276 1277 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time); 1278 if (pfx->pfx_pltimeexpire) { 1279 /* 1280 * The lifetime is decremented in real time, so we should 1281 * compare the expiration time. 1282 * (RFC 2461 Section 6.2.7.) 1283 * XXX: can we really expect that all routers on the link 1284 * have synchronized clocks? 1285 */ 1286 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1287 preferred_time += now.tv_sec; 1288 1289 if (!pfx->pfx_timer && rai->rai_clockskew && 1290 udiff(preferred_time, pfx->pfx_pltimeexpire) > rai->rai_clockskew) { 1291 syslog(LOG_INFO, 1292 "<%s> preferred lifetime for %s/%d" 1293 " (decr. in real time) inconsistent on %s:" 1294 " %" PRIu32 " from %s, %" PRIu32 " from us", 1295 __func__, 1296 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1297 sizeof(prefixbuf)), 1298 pinfo->nd_opt_pi_prefix_len, 1299 ifi->ifi_ifname, preferred_time, 1300 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1301 sizeof(ntopbuf)), pfx->pfx_pltimeexpire); 1302 inconsistent++; 1303 } 1304 } else if (!pfx->pfx_timer && preferred_time != pfx->pfx_preflifetime) 1305 syslog(LOG_INFO, 1306 "<%s> preferred lifetime for %s/%d" 1307 " inconsistent on %s:" 1308 " %d from %s, %d from us", 1309 __func__, 1310 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1311 sizeof(prefixbuf)), 1312 pinfo->nd_opt_pi_prefix_len, 1313 ifi->ifi_ifname, preferred_time, 1314 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1315 sizeof(ntopbuf)), pfx->pfx_preflifetime); 1316 1317 valid_time = ntohl(pinfo->nd_opt_pi_valid_time); 1318 if (pfx->pfx_vltimeexpire) { 1319 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 1320 valid_time += now.tv_sec; 1321 1322 if (!pfx->pfx_timer && rai->rai_clockskew && 1323 udiff(valid_time, pfx->pfx_vltimeexpire) > rai->rai_clockskew) { 1324 syslog(LOG_INFO, 1325 "<%s> valid lifetime for %s/%d" 1326 " (decr. in real time) inconsistent on %s:" 1327 " %d from %s, %" PRIu32 " from us", 1328 __func__, 1329 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1330 sizeof(prefixbuf)), 1331 pinfo->nd_opt_pi_prefix_len, 1332 ifi->ifi_ifname, preferred_time, 1333 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1334 sizeof(ntopbuf)), pfx->pfx_vltimeexpire); 1335 inconsistent++; 1336 } 1337 } else if (!pfx->pfx_timer && valid_time != pfx->pfx_validlifetime) { 1338 syslog(LOG_INFO, 1339 "<%s> valid lifetime for %s/%d" 1340 " inconsistent on %s:" 1341 " %d from %s, %d from us", 1342 __func__, 1343 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, prefixbuf, 1344 sizeof(prefixbuf)), 1345 pinfo->nd_opt_pi_prefix_len, 1346 ifi->ifi_ifname, valid_time, 1347 inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf, 1348 sizeof(ntopbuf)), pfx->pfx_validlifetime); 1349 inconsistent++; 1350 } 1351 1352 return (inconsistent); 1353 } 1354 1355 struct prefix * 1356 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen) 1357 { 1358 struct prefix *pfx; 1359 int bytelen, bitlen; 1360 char bitmask; 1361 1362 TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) { 1363 if (plen != pfx->pfx_prefixlen) 1364 continue; 1365 1366 bytelen = plen / 8; 1367 bitlen = plen % 8; 1368 bitmask = 0xff << (8 - bitlen); 1369 1370 if (memcmp((void *)prefix, (void *)&pfx->pfx_prefix, bytelen)) 1371 continue; 1372 1373 if (bitlen == 0 || 1374 ((prefix->s6_addr[bytelen] & bitmask) == 1375 (pfx->pfx_prefix.s6_addr[bytelen] & bitmask))) { 1376 return (pfx); 1377 } 1378 } 1379 1380 return (NULL); 1381 } 1382 1383 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */ 1384 int 1385 prefix_match(struct in6_addr *p0, int plen0, 1386 struct in6_addr *p1, int plen1) 1387 { 1388 int bytelen, bitlen; 1389 char bitmask; 1390 1391 if (plen0 < plen1) 1392 return (0); 1393 1394 bytelen = plen1 / 8; 1395 bitlen = plen1 % 8; 1396 bitmask = 0xff << (8 - bitlen); 1397 1398 if (memcmp((void *)p0, (void *)p1, bytelen)) 1399 return (0); 1400 1401 if (bitlen == 0 || 1402 ((p0->s6_addr[bytelen] & bitmask) == 1403 (p1->s6_addr[bytelen] & bitmask))) { 1404 return (1); 1405 } 1406 1407 return (0); 1408 } 1409 1410 static int 1411 nd6_options(struct nd_opt_hdr *hdr, int limit, 1412 union nd_opt *ndopts, uint32_t optflags) 1413 { 1414 int optlen = 0; 1415 1416 for (; limit > 0; limit -= optlen) { 1417 if ((size_t)limit < sizeof(struct nd_opt_hdr)) { 1418 syslog(LOG_INFO, "<%s> short option header", __func__); 1419 goto bad; 1420 } 1421 1422 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen); 1423 if (hdr->nd_opt_len == 0) { 1424 syslog(LOG_INFO, 1425 "<%s> bad ND option length(0) (type = %d)", 1426 __func__, hdr->nd_opt_type); 1427 goto bad; 1428 } 1429 optlen = hdr->nd_opt_len << 3; 1430 if (optlen > limit) { 1431 syslog(LOG_INFO, "<%s> short option", __func__); 1432 goto bad; 1433 } 1434 1435 if (hdr->nd_opt_type > ND_OPT_MTU && 1436 hdr->nd_opt_type != ND_OPT_RDNSS && 1437 hdr->nd_opt_type != ND_OPT_DNSSL) { 1438 syslog(LOG_INFO, "<%s> unknown ND option(type %d)", 1439 __func__, hdr->nd_opt_type); 1440 continue; 1441 } 1442 1443 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) { 1444 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)", 1445 __func__, hdr->nd_opt_type); 1446 continue; 1447 } 1448 1449 /* 1450 * Option length check. Do it here for all fixed-length 1451 * options. 1452 */ 1453 switch (hdr->nd_opt_type) { 1454 case ND_OPT_MTU: 1455 if (optlen == sizeof(struct nd_opt_mtu)) 1456 break; 1457 goto skip; 1458 case ND_OPT_RDNSS: 1459 if (optlen >= 24 && 1460 (optlen - sizeof(struct nd_opt_rdnss)) % 16 == 0) 1461 break; 1462 goto skip; 1463 case ND_OPT_DNSSL: 1464 if (optlen >= 16 && 1465 (optlen - sizeof(struct nd_opt_dnssl)) % 8 == 0) 1466 break; 1467 goto skip; 1468 case ND_OPT_PREFIX_INFORMATION: 1469 if (optlen == sizeof(struct nd_opt_prefix_info)) 1470 break; 1471 skip: 1472 syslog(LOG_INFO, "<%s> invalid option length", 1473 __func__); 1474 continue; 1475 } 1476 1477 switch (hdr->nd_opt_type) { 1478 case ND_OPT_TARGET_LINKADDR: 1479 case ND_OPT_REDIRECTED_HEADER: 1480 case ND_OPT_RDNSS: 1481 case ND_OPT_DNSSL: 1482 break; /* we don't care about these options */ 1483 case ND_OPT_SOURCE_LINKADDR: 1484 case ND_OPT_MTU: 1485 if (ndopts->opt_array[hdr->nd_opt_type]) { 1486 syslog(LOG_INFO, 1487 "<%s> duplicated ND option (type = %d)", 1488 __func__, hdr->nd_opt_type); 1489 } 1490 ndopts->opt_array[hdr->nd_opt_type] = hdr; 1491 break; 1492 case ND_OPT_PREFIX_INFORMATION: 1493 { 1494 struct nd_optlist *nol; 1495 1496 if (ndopts->opt_pi == 0) { 1497 ndopts->opt_pi = 1498 (struct nd_opt_prefix_info *)hdr; 1499 continue; 1500 } 1501 nol = malloc(sizeof(*nol)); 1502 if (nol == NULL) { 1503 syslog(LOG_ERR, "<%s> can't allocate memory", 1504 __func__); 1505 goto bad; 1506 } 1507 nol->nol_opt = hdr; 1508 TAILQ_INSERT_TAIL(&(ndopts->opt_list), nol, nol_next); 1509 1510 break; 1511 } 1512 default: /* impossible */ 1513 break; 1514 } 1515 } 1516 1517 return (0); 1518 1519 bad: 1520 free_ndopts(ndopts); 1521 1522 return (-1); 1523 } 1524 1525 static void 1526 free_ndopts(union nd_opt *ndopts) 1527 { 1528 struct nd_optlist *nol; 1529 1530 while ((nol = TAILQ_FIRST(&ndopts->opt_list)) != NULL) { 1531 TAILQ_REMOVE(&ndopts->opt_list, nol, nol_next); 1532 free(nol); 1533 } 1534 } 1535 1536 void 1537 sock_open(struct sockinfo *s) 1538 { 1539 struct icmp6_filter filt; 1540 int on; 1541 /* XXX: should be max MTU attached to the node */ 1542 static char answer[1500]; 1543 1544 syslog(LOG_DEBUG, "<%s> enter", __func__); 1545 1546 if (s == NULL) { 1547 syslog(LOG_ERR, "<%s> internal error", __func__); 1548 exit(1); 1549 } 1550 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1551 CMSG_SPACE(sizeof(int)); 1552 rcvcmsgbuf = (char *)malloc(rcvcmsgbuflen); 1553 if (rcvcmsgbuf == NULL) { 1554 syslog(LOG_ERR, "<%s> not enough core", __func__); 1555 exit(1); 1556 } 1557 1558 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1559 CMSG_SPACE(sizeof(int)); 1560 sndcmsgbuf = (char *)malloc(sndcmsgbuflen); 1561 if (sndcmsgbuf == NULL) { 1562 syslog(LOG_ERR, "<%s> not enough core", __func__); 1563 exit(1); 1564 } 1565 1566 if ((s->si_fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) { 1567 syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno)); 1568 exit(1); 1569 } 1570 /* specify to tell receiving interface */ 1571 on = 1; 1572 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 1573 sizeof(on)) < 0) { 1574 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", __func__, 1575 strerror(errno)); 1576 exit(1); 1577 } 1578 on = 1; 1579 /* specify to tell value of hoplimit field of received IP6 hdr */ 1580 if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 1581 sizeof(on)) < 0) { 1582 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", __func__, 1583 strerror(errno)); 1584 exit(1); 1585 } 1586 ICMP6_FILTER_SETBLOCKALL(&filt); 1587 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt); 1588 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt); 1589 if (mcastif != NULL) 1590 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt); 1591 1592 if (setsockopt(s->si_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, 1593 sizeof(filt)) < 0) { 1594 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s", 1595 __func__, strerror(errno)); 1596 exit(1); 1597 } 1598 1599 /* initialize msghdr for receiving packets */ 1600 rcviov[0].iov_base = (caddr_t)answer; 1601 rcviov[0].iov_len = sizeof(answer); 1602 rcvmhdr.msg_name = (caddr_t)&rcvfrom; 1603 rcvmhdr.msg_namelen = sizeof(rcvfrom); 1604 rcvmhdr.msg_iov = rcviov; 1605 rcvmhdr.msg_iovlen = 1; 1606 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf; 1607 rcvmhdr.msg_controllen = rcvcmsgbuflen; 1608 1609 /* initialize msghdr for sending packets */ 1610 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6); 1611 sndmhdr.msg_iov = sndiov; 1612 sndmhdr.msg_iovlen = 1; 1613 sndmhdr.msg_control = (caddr_t)sndcmsgbuf; 1614 sndmhdr.msg_controllen = sndcmsgbuflen; 1615 1616 return; 1617 } 1618 1619 /* open a routing socket to watch the routing table */ 1620 static void 1621 rtsock_open(struct sockinfo *s) 1622 { 1623 if (s == NULL) { 1624 syslog(LOG_ERR, "<%s> internal error", __func__); 1625 exit(1); 1626 } 1627 if ((s->si_fd = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) { 1628 syslog(LOG_ERR, 1629 "<%s> socket: %s", __func__, strerror(errno)); 1630 exit(1); 1631 } 1632 } 1633 1634 struct ifinfo * 1635 if_indextoifinfo(int idx) 1636 { 1637 struct ifinfo *ifi; 1638 char *name, name0[IFNAMSIZ]; 1639 1640 /* Check if the interface has a valid name or not. */ 1641 if (if_indextoname(idx, name0) == NULL) 1642 return (NULL); 1643 1644 TAILQ_FOREACH(ifi, &ifilist, ifi_next) { 1645 if (ifi->ifi_ifindex == idx) 1646 return (ifi); 1647 } 1648 1649 if (ifi != NULL) 1650 syslog(LOG_DEBUG, "<%s> ifi found (idx=%d)", 1651 __func__, idx); 1652 else 1653 syslog(LOG_DEBUG, "<%s> ifi not found (idx=%d)", 1654 __func__, idx); 1655 1656 return (NULL); /* search failed */ 1657 } 1658 1659 void 1660 ra_output(struct ifinfo *ifi) 1661 { 1662 int i; 1663 struct cmsghdr *cm; 1664 struct in6_pktinfo *pi; 1665 struct soliciter *sol; 1666 struct rainfo *rai; 1667 1668 switch (ifi->ifi_state) { 1669 case IFI_STATE_CONFIGURED: 1670 rai = ifi->ifi_rainfo; 1671 break; 1672 case IFI_STATE_TRANSITIVE: 1673 rai = ifi->ifi_rainfo_trans; 1674 break; 1675 case IFI_STATE_UNCONFIGURED: 1676 syslog(LOG_DEBUG, "<%s> %s is unconfigured. " 1677 "Skip sending RAs.", 1678 __func__, ifi->ifi_ifname); 1679 return; 1680 default: 1681 rai = NULL; 1682 } 1683 if (rai == NULL) { 1684 syslog(LOG_DEBUG, "<%s> rainfo is NULL on %s." 1685 "Skip sending RAs.", 1686 __func__, ifi->ifi_ifname); 1687 return; 1688 } 1689 if (!(ifi->ifi_flags & IFF_UP)) { 1690 syslog(LOG_DEBUG, "<%s> %s is not up. " 1691 "Skip sending RAs.", 1692 __func__, ifi->ifi_ifname); 1693 return; 1694 } 1695 /* 1696 * Check lifetime, ACCEPT_RTADV flag, and ip6.forwarding. 1697 * 1698 * (lifetime == 0) = output 1699 * (lifetime != 0 && (check_accept_rtadv()) = no output 1700 * 1701 * Basically, hosts MUST NOT send Router Advertisement 1702 * messages at any time (RFC 4861, Section 6.2.3). However, it 1703 * would sometimes be useful to allow hosts to advertise some 1704 * parameters such as prefix information and link MTU. Thus, 1705 * we allow hosts to invoke rtadvd only when router lifetime 1706 * (on every advertising interface) is explicitly set 1707 * zero. (see also the above section) 1708 */ 1709 syslog(LOG_DEBUG, 1710 "<%s> check lifetime=%d, ACCEPT_RTADV=%d, ip6.forwarding=%d " 1711 "on %s", __func__, 1712 rai->rai_lifetime, 1713 check_accept_rtadv(ifi->ifi_ifindex), 1714 getinet6sysctl(IPV6CTL_FORWARDING), 1715 ifi->ifi_ifname); 1716 1717 if (rai->rai_lifetime != 0) { 1718 if (getinet6sysctl(IPV6CTL_FORWARDING) == 0) { 1719 syslog(LOG_ERR, 1720 "non-zero lifetime RA " 1721 "but net.inet6.ip6.forwarding=0. " 1722 "Ignored."); 1723 return; 1724 } 1725 if (check_accept_rtadv(ifi->ifi_ifindex)) { 1726 syslog(LOG_ERR, 1727 "non-zero lifetime RA " 1728 "on RA receiving interface %s." 1729 " Ignored.", ifi->ifi_ifname); 1730 return; 1731 } 1732 } 1733 1734 make_packet(rai); /* XXX: inefficient */ 1735 1736 sndmhdr.msg_name = (caddr_t)&sin6_linklocal_allnodes; 1737 sndmhdr.msg_iov[0].iov_base = (caddr_t)rai->rai_ra_data; 1738 sndmhdr.msg_iov[0].iov_len = rai->rai_ra_datalen; 1739 1740 cm = CMSG_FIRSTHDR(&sndmhdr); 1741 /* specify the outgoing interface */ 1742 cm->cmsg_level = IPPROTO_IPV6; 1743 cm->cmsg_type = IPV6_PKTINFO; 1744 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); 1745 pi = (struct in6_pktinfo *)CMSG_DATA(cm); 1746 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/ 1747 pi->ipi6_ifindex = ifi->ifi_ifindex; 1748 1749 /* specify the hop limit of the packet */ 1750 { 1751 int hoplimit = 255; 1752 1753 cm = CMSG_NXTHDR(&sndmhdr, cm); 1754 cm->cmsg_level = IPPROTO_IPV6; 1755 cm->cmsg_type = IPV6_HOPLIMIT; 1756 cm->cmsg_len = CMSG_LEN(sizeof(int)); 1757 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int)); 1758 } 1759 1760 syslog(LOG_DEBUG, 1761 "<%s> send RA on %s, # of RS waitings = %d", 1762 __func__, ifi->ifi_ifname, ifi->ifi_rs_waitcount); 1763 1764 i = sendmsg(sock.si_fd, &sndmhdr, 0); 1765 1766 if (i < 0 || (size_t)i != rai->rai_ra_datalen) { 1767 if (i < 0) { 1768 syslog(LOG_ERR, "<%s> sendmsg on %s: %s", 1769 __func__, ifi->ifi_ifname, 1770 strerror(errno)); 1771 } 1772 } 1773 1774 /* 1775 * unicast advertisements 1776 * XXX commented out. reason: though spec does not forbit it, unicast 1777 * advert does not really help 1778 */ 1779 while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) { 1780 TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next); 1781 free(sol); 1782 } 1783 1784 /* update timestamp */ 1785 clock_gettime(CLOCK_MONOTONIC_FAST, &ifi->ifi_ra_lastsent); 1786 1787 /* update counter */ 1788 ifi->ifi_rs_waitcount = 0; 1789 ifi->ifi_raoutput++; 1790 1791 switch (ifi->ifi_state) { 1792 case IFI_STATE_CONFIGURED: 1793 if (ifi->ifi_burstcount > 0) 1794 ifi->ifi_burstcount--; 1795 break; 1796 case IFI_STATE_TRANSITIVE: 1797 ifi->ifi_burstcount--; 1798 if (ifi->ifi_burstcount == 0) { 1799 if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) { 1800 /* Initial burst finished. */ 1801 if (ifi->ifi_rainfo_trans != NULL) 1802 ifi->ifi_rainfo_trans = NULL; 1803 } 1804 1805 /* Remove burst RA information */ 1806 if (ifi->ifi_rainfo_trans != NULL) { 1807 rm_rainfo(ifi->ifi_rainfo_trans); 1808 ifi->ifi_rainfo_trans = NULL; 1809 } 1810 1811 if (ifi->ifi_rainfo != NULL) { 1812 /* 1813 * TRANSITIVE -> CONFIGURED 1814 * 1815 * After initial burst or transition from 1816 * one configuration to another, 1817 * ifi_rainfo always points to the next RA 1818 * information. 1819 */ 1820 ifi->ifi_state = IFI_STATE_CONFIGURED; 1821 syslog(LOG_DEBUG, 1822 "<%s> ifname=%s marked as " 1823 "CONFIGURED.", __func__, 1824 ifi->ifi_ifname); 1825 } else { 1826 /* 1827 * TRANSITIVE -> UNCONFIGURED 1828 * 1829 * If ifi_rainfo points to NULL, this 1830 * interface is shutting down. 1831 * 1832 */ 1833 int error; 1834 1835 ifi->ifi_state = IFI_STATE_UNCONFIGURED; 1836 syslog(LOG_DEBUG, 1837 "<%s> ifname=%s marked as " 1838 "UNCONFIGURED.", __func__, 1839 ifi->ifi_ifname); 1840 error = sock_mc_leave(&sock, 1841 ifi->ifi_ifindex); 1842 if (error) 1843 exit(1); 1844 } 1845 } 1846 break; 1847 } 1848 } 1849 1850 /* process RA timer */ 1851 struct rtadvd_timer * 1852 ra_timeout(void *arg) 1853 { 1854 struct ifinfo *ifi; 1855 1856 ifi = (struct ifinfo *)arg; 1857 syslog(LOG_DEBUG, "<%s> RA timer on %s is expired", 1858 __func__, ifi->ifi_ifname); 1859 1860 ra_output(ifi); 1861 1862 return (ifi->ifi_ra_timer); 1863 } 1864 1865 /* update RA timer */ 1866 void 1867 ra_timer_update(void *arg, struct timespec *tm) 1868 { 1869 uint16_t interval; 1870 struct rainfo *rai; 1871 struct ifinfo *ifi; 1872 1873 ifi = (struct ifinfo *)arg; 1874 rai = ifi->ifi_rainfo; 1875 interval = 0; 1876 1877 switch (ifi->ifi_state) { 1878 case IFI_STATE_UNCONFIGURED: 1879 return; 1880 break; 1881 case IFI_STATE_CONFIGURED: 1882 /* 1883 * Whenever a multicast advertisement is sent from 1884 * an interface, the timer is reset to a 1885 * uniformly-distributed random value between the 1886 * interface's configured MinRtrAdvInterval and 1887 * MaxRtrAdvInterval (RFC4861 6.2.4). 1888 */ 1889 interval = rai->rai_mininterval; 1890 interval += arc4random_uniform(rai->rai_maxinterval - 1891 rai->rai_mininterval); 1892 break; 1893 case IFI_STATE_TRANSITIVE: 1894 /* 1895 * For the first few advertisements (up to 1896 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen 1897 * interval is greater than 1898 * MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer SHOULD be 1899 * set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. (RFC 1900 * 4861 6.2.4) 1901 * 1902 * In such cases, the router SHOULD transmit one or more 1903 * (but not more than MAX_FINAL_RTR_ADVERTISEMENTS) final 1904 * multicast Router Advertisements on the interface with a 1905 * Router Lifetime field of zero. (RFC 4861 6.2.5) 1906 */ 1907 interval = ifi->ifi_burstinterval; 1908 break; 1909 } 1910 1911 tm->tv_sec = interval; 1912 tm->tv_nsec = 0; 1913 1914 syslog(LOG_DEBUG, 1915 "<%s> RA timer on %s is set to %ld:%ld", 1916 __func__, ifi->ifi_ifname, 1917 (long int)tm->tv_sec, (long int)tm->tv_nsec / 1000); 1918 1919 return; 1920 } 1921