1 /* $FreeBSD$ */ 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 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/param.h> 34 #include <sys/socket.h> 35 #include <sys/uio.h> 36 #include <sys/time.h> 37 #include <sys/queue.h> 38 39 #include <net/if.h> 40 #include <net/route.h> 41 #include <net/if_dl.h> 42 #include <netinet/in.h> 43 #include <netinet/ip6.h> 44 #include <netinet6/ip6_var.h> 45 #include <netinet/icmp6.h> 46 47 #include <arpa/inet.h> 48 49 #include <time.h> 50 #include <unistd.h> 51 #include <stdio.h> 52 #include <err.h> 53 #include <errno.h> 54 #include <libutil.h> 55 #include <string.h> 56 #include <stdlib.h> 57 #include <syslog.h> 58 #ifdef HAVE_POLL_H 59 #include <poll.h> 60 #endif 61 62 #include "rtadvd.h" 63 #include "rrenum.h" 64 #include "advcap.h" 65 #include "timer.h" 66 #include "if.h" 67 #include "config.h" 68 #include "dump.h" 69 70 struct msghdr rcvmhdr; 71 static u_char *rcvcmsgbuf; 72 static size_t rcvcmsgbuflen; 73 static u_char *sndcmsgbuf = NULL; 74 static size_t sndcmsgbuflen; 75 volatile sig_atomic_t do_dump; 76 volatile sig_atomic_t do_die; 77 struct msghdr sndmhdr; 78 struct iovec rcviov[2]; 79 struct iovec sndiov[2]; 80 struct sockaddr_in6 rcvfrom; 81 struct sockaddr_in6 sin6_allnodes = {sizeof(sin6_allnodes), AF_INET6}; 82 struct in6_addr in6a_site_allrouters; 83 static char *dumpfilename = "/var/run/rtadvd.dump"; 84 static char *pidfilename = "/var/run/rtadvd.pid"; 85 static struct pidfh *pfh; 86 static char *mcastif; 87 int sock; 88 int rtsock = -1; 89 int accept_rr = 0; 90 int dflag = 0, sflag = 0; 91 92 u_char *conffile = NULL; 93 94 struct rainfo *ralist = NULL; 95 struct nd_optlist { 96 struct nd_optlist *next; 97 struct nd_opt_hdr *opt; 98 }; 99 union nd_opts { 100 struct nd_opt_hdr *nd_opt_array[9]; 101 struct { 102 struct nd_opt_hdr *zero; 103 struct nd_opt_hdr *src_lladdr; 104 struct nd_opt_hdr *tgt_lladdr; 105 struct nd_opt_prefix_info *pi; 106 struct nd_opt_rd_hdr *rh; 107 struct nd_opt_mtu *mtu; 108 struct nd_optlist *list; 109 } nd_opt_each; 110 }; 111 #define nd_opts_src_lladdr nd_opt_each.src_lladdr 112 #define nd_opts_tgt_lladdr nd_opt_each.tgt_lladdr 113 #define nd_opts_pi nd_opt_each.pi 114 #define nd_opts_rh nd_opt_each.rh 115 #define nd_opts_mtu nd_opt_each.mtu 116 #define nd_opts_list nd_opt_each.list 117 118 #define NDOPT_FLAG_SRCLINKADDR 0x1 119 #define NDOPT_FLAG_TGTLINKADDR 0x2 120 #define NDOPT_FLAG_PREFIXINFO 0x4 121 #define NDOPT_FLAG_RDHDR 0x8 122 #define NDOPT_FLAG_MTU 0x10 123 124 u_int32_t ndopt_flags[] = { 125 0, NDOPT_FLAG_SRCLINKADDR, NDOPT_FLAG_TGTLINKADDR, 126 NDOPT_FLAG_PREFIXINFO, NDOPT_FLAG_RDHDR, NDOPT_FLAG_MTU, 127 }; 128 129 int main(int, char *[]); 130 static void set_die(int); 131 static void die(void); 132 static void sock_open(void); 133 static void rtsock_open(void); 134 static void rtadvd_input(void); 135 static void rs_input(int, struct nd_router_solicit *, 136 struct in6_pktinfo *, struct sockaddr_in6 *); 137 static void ra_input(int, struct nd_router_advert *, 138 struct in6_pktinfo *, struct sockaddr_in6 *); 139 static int prefix_check(struct nd_opt_prefix_info *, struct rainfo *, 140 struct sockaddr_in6 *); 141 static int nd6_options(struct nd_opt_hdr *, int, 142 union nd_opts *, u_int32_t); 143 static void free_ndopts(union nd_opts *); 144 static void ra_output(struct rainfo *); 145 static void rtmsg_input(void); 146 static void rtadvd_set_dump_file(int); 147 static void set_short_delay(struct rainfo *); 148 149 int 150 main(argc, argv) 151 int argc; 152 char *argv[]; 153 { 154 #ifdef HAVE_POLL_H 155 struct pollfd set[2]; 156 #else 157 fd_set *fdsetp, *selectfdp; 158 int fdmasks; 159 int maxfd = 0; 160 #endif 161 struct timeval *timeout; 162 int i, ch; 163 int fflag = 0, logopt; 164 pid_t pid, otherpid; 165 166 /* get command line options and arguments */ 167 while ((ch = getopt(argc, argv, "c:dDF:fMp:Rs")) != -1) { 168 switch (ch) { 169 case 'c': 170 conffile = optarg; 171 break; 172 case 'd': 173 dflag = 1; 174 break; 175 case 'D': 176 dflag = 2; 177 break; 178 case 'f': 179 fflag = 1; 180 break; 181 case 'M': 182 mcastif = optarg; 183 break; 184 case 'R': 185 fprintf(stderr, "rtadvd: " 186 "the -R option is currently ignored.\n"); 187 /* accept_rr = 1; */ 188 /* run anyway... */ 189 break; 190 case 's': 191 sflag = 1; 192 break; 193 case 'p': 194 pidfilename = optarg; 195 break; 196 case 'F': 197 dumpfilename = optarg; 198 break; 199 } 200 } 201 argc -= optind; 202 argv += optind; 203 if (argc == 0) { 204 fprintf(stderr, 205 "usage: rtadvd [-dDfMRs] [-c conffile] " 206 "[-F dumpfile] [-p pidfile] interfaces...\n"); 207 exit(1); 208 } 209 210 logopt = LOG_NDELAY | LOG_PID; 211 if (fflag) 212 logopt |= LOG_PERROR; 213 openlog("rtadvd", logopt, LOG_DAEMON); 214 215 /* set log level */ 216 if (dflag == 0) 217 (void)setlogmask(LOG_UPTO(LOG_ERR)); 218 if (dflag == 1) 219 (void)setlogmask(LOG_UPTO(LOG_INFO)); 220 221 /* timer initialization */ 222 rtadvd_timer_init(); 223 224 #ifndef HAVE_ARC4RANDOM 225 /* random value initialization */ 226 #ifdef __FreeBSD__ 227 srandomdev(); 228 #else 229 srandom((u_long)time(NULL)); 230 #endif 231 #endif 232 233 /* get iflist block from kernel */ 234 init_iflist(); 235 236 while (argc--) 237 getconfig(*argv++); 238 239 if (inet_pton(AF_INET6, ALLNODES, &sin6_allnodes.sin6_addr) != 1) { 240 fprintf(stderr, "fatal: inet_pton failed\n"); 241 exit(1); 242 } 243 244 pfh = pidfile_open(pidfilename, 0600, &otherpid); 245 if (pfh == NULL) { 246 if (errno == EEXIST) 247 errx(1, "%s already running, pid: %d", 248 getprogname(), otherpid); 249 syslog(LOG_ERR, 250 "<%s> failed to open the pid log file, run anyway.", 251 __func__); 252 } 253 254 if (!fflag) 255 daemon(1, 0); 256 257 sock_open(); 258 259 /* record the current PID */ 260 pid = getpid(); 261 pidfile_write(pfh); 262 263 #ifdef HAVE_POLL_H 264 set[0].fd = sock; 265 set[0].events = POLLIN; 266 if (sflag == 0) { 267 rtsock_open(); 268 set[1].fd = rtsock; 269 set[1].events = POLLIN; 270 } else 271 set[1].fd = -1; 272 #else 273 maxfd = sock; 274 if (sflag == 0) { 275 rtsock_open(); 276 if (rtsock > sock) 277 maxfd = rtsock; 278 } else 279 rtsock = -1; 280 281 fdmasks = howmany(maxfd + 1, NFDBITS) * sizeof(fd_mask); 282 if ((fdsetp = malloc(fdmasks)) == NULL) { 283 err(1, "malloc"); 284 /*NOTREACHED*/ 285 } 286 if ((selectfdp = malloc(fdmasks)) == NULL) { 287 err(1, "malloc"); 288 /*NOTREACHED*/ 289 } 290 memset(fdsetp, 0, fdmasks); 291 FD_SET(sock, fdsetp); 292 if (rtsock >= 0) 293 FD_SET(rtsock, fdsetp); 294 #endif 295 296 signal(SIGTERM, set_die); 297 signal(SIGUSR1, rtadvd_set_dump_file); 298 299 while (1) { 300 #ifndef HAVE_POLL_H 301 memcpy(selectfdp, fdsetp, fdmasks); /* reinitialize */ 302 #endif 303 304 if (do_dump) { /* SIGUSR1 */ 305 do_dump = 0; 306 rtadvd_dump_file(dumpfilename); 307 } 308 309 if (do_die) { 310 die(); 311 /*NOTREACHED*/ 312 } 313 314 /* timer expiration check and reset the timer */ 315 timeout = rtadvd_check_timer(); 316 317 if (timeout != NULL) { 318 syslog(LOG_DEBUG, 319 "<%s> set timer to %ld:%ld. waiting for " 320 "inputs or timeout", __func__, 321 (long int)timeout->tv_sec, 322 (long int)timeout->tv_usec); 323 } else { 324 syslog(LOG_DEBUG, 325 "<%s> there's no timer. waiting for inputs", 326 __func__); 327 } 328 329 #ifdef HAVE_POLL_H 330 if ((i = poll(set, 2, timeout ? (timeout->tv_sec * 1000 + 331 timeout->tv_usec / 1000) : INFTIM)) < 0) 332 #else 333 if ((i = select(maxfd + 1, selectfdp, NULL, NULL, 334 timeout)) < 0) 335 #endif 336 { 337 /* EINTR would occur upon SIGUSR1 for status dump */ 338 if (errno != EINTR) 339 syslog(LOG_ERR, "<%s> select: %s", 340 __func__, strerror(errno)); 341 continue; 342 } 343 if (i == 0) /* timeout */ 344 continue; 345 #ifdef HAVE_POLL_H 346 if (rtsock != -1 && set[1].revents & POLLIN) 347 #else 348 if (rtsock != -1 && FD_ISSET(rtsock, selectfdp)) 349 #endif 350 rtmsg_input(); 351 #ifdef HAVE_POLL_H 352 if (set[0].revents & POLLIN) 353 #else 354 if (FD_ISSET(sock, selectfdp)) 355 #endif 356 rtadvd_input(); 357 } 358 exit(0); /* NOTREACHED */ 359 } 360 361 static void 362 rtadvd_set_dump_file(sig) 363 int sig; 364 { 365 do_dump = 1; 366 } 367 368 static void 369 set_die(sig) 370 int sig; 371 { 372 do_die = 1; 373 } 374 375 static void 376 die() 377 { 378 struct rainfo *ra; 379 int i; 380 const int retrans = MAX_FINAL_RTR_ADVERTISEMENTS; 381 382 if (dflag > 1) { 383 syslog(LOG_DEBUG, "<%s> cease to be an advertising router\n", 384 __func__); 385 } 386 387 for (ra = ralist; ra; ra = ra->next) { 388 ra->lifetime = 0; 389 make_packet(ra); 390 } 391 for (i = 0; i < retrans; i++) { 392 for (ra = ralist; ra; ra = ra->next) 393 ra_output(ra); 394 sleep(MIN_DELAY_BETWEEN_RAS); 395 } 396 pidfile_remove(pfh); 397 exit(0); 398 /*NOTREACHED*/ 399 } 400 401 static void 402 rtmsg_input() 403 { 404 int n, type, ifindex = 0, plen; 405 size_t len; 406 char msg[2048], *next, *lim; 407 u_char ifname[IF_NAMESIZE]; 408 struct prefix *prefix; 409 struct rainfo *rai; 410 struct in6_addr *addr; 411 char addrbuf[INET6_ADDRSTRLEN]; 412 int prefixchange = 0; 413 414 n = read(rtsock, msg, sizeof(msg)); 415 if (dflag > 1) { 416 syslog(LOG_DEBUG, "<%s> received a routing message " 417 "(type = %d, len = %d)", __func__, rtmsg_type(msg), n); 418 } 419 if (n > rtmsg_len(msg)) { 420 /* 421 * This usually won't happen for messages received on 422 * a routing socket. 423 */ 424 if (dflag > 1) 425 syslog(LOG_DEBUG, 426 "<%s> received data length is larger than " 427 "1st routing message len. multiple messages? " 428 "read %d bytes, but 1st msg len = %d", 429 __func__, n, rtmsg_len(msg)); 430 #if 0 431 /* adjust length */ 432 n = rtmsg_len(msg); 433 #endif 434 } 435 436 lim = msg + n; 437 for (next = msg; next < lim; next += len) { 438 int oldifflags; 439 440 next = get_next_msg(next, lim, 0, &len, 441 RTADV_TYPE2BITMASK(RTM_ADD) | 442 RTADV_TYPE2BITMASK(RTM_DELETE) | 443 RTADV_TYPE2BITMASK(RTM_NEWADDR) | 444 RTADV_TYPE2BITMASK(RTM_DELADDR) | 445 RTADV_TYPE2BITMASK(RTM_IFINFO)); 446 if (len == 0) 447 break; 448 type = rtmsg_type(next); 449 switch (type) { 450 case RTM_ADD: 451 case RTM_DELETE: 452 ifindex = get_rtm_ifindex(next); 453 break; 454 case RTM_NEWADDR: 455 case RTM_DELADDR: 456 ifindex = get_ifam_ifindex(next); 457 break; 458 case RTM_IFINFO: 459 ifindex = get_ifm_ifindex(next); 460 break; 461 default: 462 /* should not reach here */ 463 if (dflag > 1) { 464 syslog(LOG_DEBUG, 465 "<%s:%d> unknown rtmsg %d on %s", 466 __func__, __LINE__, type, 467 if_indextoname(ifindex, ifname)); 468 } 469 continue; 470 } 471 472 if ((rai = if_indextorainfo(ifindex)) == NULL) { 473 if (dflag > 1) { 474 syslog(LOG_DEBUG, 475 "<%s> route changed on " 476 "non advertising interface(%s)", 477 __func__, 478 if_indextoname(ifindex, ifname)); 479 } 480 continue; 481 } 482 oldifflags = iflist[ifindex]->ifm_flags; 483 484 switch (type) { 485 case RTM_ADD: 486 /* init ifflags because it may have changed */ 487 iflist[ifindex]->ifm_flags = 488 if_getflags(ifindex, iflist[ifindex]->ifm_flags); 489 490 if (sflag) 491 break; /* we aren't interested in prefixes */ 492 493 addr = get_addr(msg); 494 plen = get_prefixlen(msg); 495 /* sanity check for plen */ 496 /* as RFC2373, prefixlen is at least 4 */ 497 if (plen < 4 || plen > 127) { 498 syslog(LOG_INFO, "<%s> new interface route's" 499 "plen %d is invalid for a prefix", 500 __func__, plen); 501 break; 502 } 503 prefix = find_prefix(rai, addr, plen); 504 if (prefix) { 505 if (prefix->timer) { 506 /* 507 * If the prefix has been invalidated, 508 * make it available again. 509 */ 510 update_prefix(prefix); 511 prefixchange = 1; 512 } else if (dflag > 1) { 513 syslog(LOG_DEBUG, 514 "<%s> new prefix(%s/%d) " 515 "added on %s, " 516 "but it was already in list", 517 __func__, 518 inet_ntop(AF_INET6, addr, 519 (char *)addrbuf, INET6_ADDRSTRLEN), 520 plen, rai->ifname); 521 } 522 break; 523 } 524 make_prefix(rai, ifindex, addr, plen); 525 prefixchange = 1; 526 break; 527 case RTM_DELETE: 528 /* init ifflags because it may have changed */ 529 iflist[ifindex]->ifm_flags = 530 if_getflags(ifindex, iflist[ifindex]->ifm_flags); 531 532 if (sflag) 533 break; 534 535 addr = get_addr(msg); 536 plen = get_prefixlen(msg); 537 /* sanity check for plen */ 538 /* as RFC2373, prefixlen is at least 4 */ 539 if (plen < 4 || plen > 127) { 540 syslog(LOG_INFO, 541 "<%s> deleted interface route's " 542 "plen %d is invalid for a prefix", 543 __func__, plen); 544 break; 545 } 546 prefix = find_prefix(rai, addr, plen); 547 if (prefix == NULL) { 548 if (dflag > 1) { 549 syslog(LOG_DEBUG, 550 "<%s> prefix(%s/%d) was " 551 "deleted on %s, " 552 "but it was not in list", 553 __func__, 554 inet_ntop(AF_INET6, addr, 555 (char *)addrbuf, INET6_ADDRSTRLEN), 556 plen, rai->ifname); 557 } 558 break; 559 } 560 invalidate_prefix(prefix); 561 prefixchange = 1; 562 break; 563 case RTM_NEWADDR: 564 case RTM_DELADDR: 565 /* init ifflags because it may have changed */ 566 iflist[ifindex]->ifm_flags = 567 if_getflags(ifindex, iflist[ifindex]->ifm_flags); 568 break; 569 case RTM_IFINFO: 570 iflist[ifindex]->ifm_flags = get_ifm_flags(next); 571 break; 572 default: 573 /* should not reach here */ 574 if (dflag > 1) { 575 syslog(LOG_DEBUG, 576 "<%s:%d> unknown rtmsg %d on %s", 577 __func__, __LINE__, type, 578 if_indextoname(ifindex, ifname)); 579 } 580 return; 581 } 582 583 /* check if an interface flag is changed */ 584 if ((oldifflags & IFF_UP) && /* UP to DOWN */ 585 !(iflist[ifindex]->ifm_flags & IFF_UP)) { 586 syslog(LOG_INFO, 587 "<%s> interface %s becomes down. stop timer.", 588 __func__, rai->ifname); 589 rtadvd_remove_timer(&rai->timer); 590 } else if (!(oldifflags & IFF_UP) && /* DOWN to UP */ 591 (iflist[ifindex]->ifm_flags & IFF_UP)) { 592 syslog(LOG_INFO, 593 "<%s> interface %s becomes up. restart timer.", 594 __func__, rai->ifname); 595 596 rai->initcounter = 0; /* reset the counter */ 597 rai->waiting = 0; /* XXX */ 598 rai->timer = rtadvd_add_timer(ra_timeout, 599 ra_timer_update, rai, rai); 600 ra_timer_update((void *)rai, &rai->timer->tm); 601 rtadvd_set_timer(&rai->timer->tm, rai->timer); 602 } else if (prefixchange && 603 (iflist[ifindex]->ifm_flags & IFF_UP)) { 604 /* 605 * An advertised prefix has been added or invalidated. 606 * Will notice the change in a short delay. 607 */ 608 rai->initcounter = 0; 609 set_short_delay(rai); 610 } 611 } 612 613 return; 614 } 615 616 void 617 rtadvd_input() 618 { 619 int i; 620 int *hlimp = NULL; 621 #ifdef OLDRAWSOCKET 622 struct ip6_hdr *ip; 623 #endif 624 struct icmp6_hdr *icp; 625 int ifindex = 0; 626 struct cmsghdr *cm; 627 struct in6_pktinfo *pi = NULL; 628 u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; 629 struct in6_addr dst = in6addr_any; 630 631 /* 632 * Get message. We reset msg_controllen since the field could 633 * be modified if we had received a message before setting 634 * receive options. 635 */ 636 rcvmhdr.msg_controllen = rcvcmsgbuflen; 637 if ((i = recvmsg(sock, &rcvmhdr, 0)) < 0) 638 return; 639 640 /* extract optional information via Advanced API */ 641 for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr); 642 cm; 643 cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) { 644 if (cm->cmsg_level == IPPROTO_IPV6 && 645 cm->cmsg_type == IPV6_PKTINFO && 646 cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) { 647 pi = (struct in6_pktinfo *)(CMSG_DATA(cm)); 648 ifindex = pi->ipi6_ifindex; 649 dst = pi->ipi6_addr; 650 } 651 if (cm->cmsg_level == IPPROTO_IPV6 && 652 cm->cmsg_type == IPV6_HOPLIMIT && 653 cm->cmsg_len == CMSG_LEN(sizeof(int))) 654 hlimp = (int *)CMSG_DATA(cm); 655 } 656 if (ifindex == 0) { 657 syslog(LOG_ERR, 658 "<%s> failed to get receiving interface", 659 __func__); 660 return; 661 } 662 if (hlimp == NULL) { 663 syslog(LOG_ERR, 664 "<%s> failed to get receiving hop limit", 665 __func__); 666 return; 667 } 668 669 /* 670 * If we happen to receive data on an interface which is now down, 671 * just discard the data. 672 */ 673 if ((iflist[pi->ipi6_ifindex]->ifm_flags & IFF_UP) == 0) { 674 syslog(LOG_INFO, 675 "<%s> received data on a disabled interface (%s)", 676 __func__, 677 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 678 return; 679 } 680 681 #ifdef OLDRAWSOCKET 682 if (i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) { 683 syslog(LOG_ERR, 684 "<%s> packet size(%d) is too short", 685 __func__, i); 686 return; 687 } 688 689 ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base; 690 icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */ 691 #else 692 if (i < sizeof(struct icmp6_hdr)) { 693 syslog(LOG_ERR, 694 "<%s> packet size(%d) is too short", 695 __func__, i); 696 return; 697 } 698 699 icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base; 700 #endif 701 702 switch (icp->icmp6_type) { 703 case ND_ROUTER_SOLICIT: 704 /* 705 * Message verification - RFC-2461 6.1.1 706 * XXX: these checks must be done in the kernel as well, 707 * but we can't completely rely on them. 708 */ 709 if (*hlimp != 255) { 710 syslog(LOG_NOTICE, 711 "<%s> RS with invalid hop limit(%d) " 712 "received from %s on %s", 713 __func__, *hlimp, 714 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 715 INET6_ADDRSTRLEN), 716 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 717 return; 718 } 719 if (icp->icmp6_code) { 720 syslog(LOG_NOTICE, 721 "<%s> RS with invalid ICMP6 code(%d) " 722 "received from %s on %s", 723 __func__, icp->icmp6_code, 724 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 725 INET6_ADDRSTRLEN), 726 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 727 return; 728 } 729 if (i < sizeof(struct nd_router_solicit)) { 730 syslog(LOG_NOTICE, 731 "<%s> RS from %s on %s does not have enough " 732 "length (len = %d)", 733 __func__, 734 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 735 INET6_ADDRSTRLEN), 736 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 737 return; 738 } 739 rs_input(i, (struct nd_router_solicit *)icp, pi, &rcvfrom); 740 break; 741 case ND_ROUTER_ADVERT: 742 /* 743 * Message verification - RFC-2461 6.1.2 744 * XXX: there's a same dilemma as above... 745 */ 746 if (*hlimp != 255) { 747 syslog(LOG_NOTICE, 748 "<%s> RA with invalid hop limit(%d) " 749 "received from %s on %s", 750 __func__, *hlimp, 751 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 752 INET6_ADDRSTRLEN), 753 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 754 return; 755 } 756 if (icp->icmp6_code) { 757 syslog(LOG_NOTICE, 758 "<%s> RA with invalid ICMP6 code(%d) " 759 "received from %s on %s", 760 __func__, icp->icmp6_code, 761 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 762 INET6_ADDRSTRLEN), 763 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 764 return; 765 } 766 if (i < sizeof(struct nd_router_advert)) { 767 syslog(LOG_NOTICE, 768 "<%s> RA from %s on %s does not have enough " 769 "length (len = %d)", 770 __func__, 771 inet_ntop(AF_INET6, &rcvfrom.sin6_addr, ntopbuf, 772 INET6_ADDRSTRLEN), 773 if_indextoname(pi->ipi6_ifindex, ifnamebuf), i); 774 return; 775 } 776 ra_input(i, (struct nd_router_advert *)icp, pi, &rcvfrom); 777 break; 778 case ICMP6_ROUTER_RENUMBERING: 779 if (accept_rr == 0) { 780 syslog(LOG_ERR, "<%s> received a router renumbering " 781 "message, but not allowed to be accepted", 782 __func__); 783 break; 784 } 785 rr_input(i, (struct icmp6_router_renum *)icp, pi, &rcvfrom, 786 &dst); 787 break; 788 default: 789 /* 790 * Note that this case is POSSIBLE, especially just 791 * after invocation of the daemon. This is because we 792 * could receive message after opening the socket and 793 * before setting ICMP6 type filter(see sock_open()). 794 */ 795 syslog(LOG_ERR, "<%s> invalid icmp type(%d)", 796 __func__, icp->icmp6_type); 797 return; 798 } 799 800 return; 801 } 802 803 static void 804 rs_input(int len, struct nd_router_solicit *rs, 805 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 806 { 807 u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; 808 union nd_opts ndopts; 809 struct rainfo *ra; 810 struct soliciter *sol; 811 812 syslog(LOG_DEBUG, 813 "<%s> RS received from %s on %s", 814 __func__, 815 inet_ntop(AF_INET6, &from->sin6_addr, 816 ntopbuf, INET6_ADDRSTRLEN), 817 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 818 819 /* ND option check */ 820 memset(&ndopts, 0, sizeof(ndopts)); 821 if (nd6_options((struct nd_opt_hdr *)(rs + 1), 822 len - sizeof(struct nd_router_solicit), 823 &ndopts, NDOPT_FLAG_SRCLINKADDR)) { 824 syslog(LOG_INFO, 825 "<%s> ND option check failed for an RS from %s on %s", 826 __func__, 827 inet_ntop(AF_INET6, &from->sin6_addr, 828 ntopbuf, INET6_ADDRSTRLEN), 829 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 830 return; 831 } 832 833 /* 834 * If the IP source address is the unspecified address, there 835 * must be no source link-layer address option in the message. 836 * (RFC-2461 6.1.1) 837 */ 838 if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) && 839 ndopts.nd_opts_src_lladdr) { 840 syslog(LOG_INFO, 841 "<%s> RS from unspecified src on %s has a link-layer" 842 " address option", 843 __func__, 844 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 845 goto done; 846 } 847 848 ra = ralist; 849 while (ra != NULL) { 850 if (pi->ipi6_ifindex == ra->ifindex) 851 break; 852 ra = ra->next; 853 } 854 if (ra == NULL) { 855 syslog(LOG_INFO, 856 "<%s> RS received on non advertising interface(%s)", 857 __func__, 858 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 859 goto done; 860 } 861 862 ra->rsinput++; /* increment statistics */ 863 864 /* 865 * Decide whether to send RA according to the rate-limit 866 * consideration. 867 */ 868 869 /* record sockaddr waiting for RA, if possible */ 870 sol = (struct soliciter *)malloc(sizeof(*sol)); 871 if (sol) { 872 sol->addr = *from; 873 /* XXX RFC2553 need clarification on flowinfo */ 874 sol->addr.sin6_flowinfo = 0; 875 sol->next = ra->soliciter; 876 ra->soliciter = sol; 877 } 878 879 /* 880 * If there is already a waiting RS packet, don't 881 * update the timer. 882 */ 883 if (ra->waiting++) 884 goto done; 885 886 set_short_delay(ra); 887 888 done: 889 free_ndopts(&ndopts); 890 return; 891 } 892 893 static void 894 set_short_delay(rai) 895 struct rainfo *rai; 896 { 897 long delay; /* must not be greater than 1000000 */ 898 struct timeval interval, now, min_delay, tm_tmp, *rest; 899 900 /* 901 * Compute a random delay. If the computed value 902 * corresponds to a time later than the time the next 903 * multicast RA is scheduled to be sent, ignore the random 904 * delay and send the advertisement at the 905 * already-scheduled time. RFC-2461 6.2.6 906 */ 907 #ifdef HAVE_ARC4RANDOM 908 delay = arc4random_uniform(MAX_RA_DELAY_TIME); 909 #else 910 delay = random() % MAX_RA_DELAY_TIME; 911 #endif 912 interval.tv_sec = 0; 913 interval.tv_usec = delay; 914 rest = rtadvd_timer_rest(rai->timer); 915 if (TIMEVAL_LT(*rest, interval)) { 916 syslog(LOG_DEBUG, "<%s> random delay is larger than " 917 "the rest of the current timer", __func__); 918 interval = *rest; 919 } 920 921 /* 922 * If we sent a multicast Router Advertisement within 923 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule 924 * the advertisement to be sent at a time corresponding to 925 * MIN_DELAY_BETWEEN_RAS plus the random value after the 926 * previous advertisement was sent. 927 */ 928 gettimeofday(&now, NULL); 929 TIMEVAL_SUB(&now, &rai->lastsent, &tm_tmp); 930 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS; 931 min_delay.tv_usec = 0; 932 if (TIMEVAL_LT(tm_tmp, min_delay)) { 933 TIMEVAL_SUB(&min_delay, &tm_tmp, &min_delay); 934 TIMEVAL_ADD(&min_delay, &interval, &interval); 935 } 936 rtadvd_set_timer(&interval, rai->timer); 937 } 938 939 static void 940 ra_input(int len, struct nd_router_advert *ra, 941 struct in6_pktinfo *pi, struct sockaddr_in6 *from) 942 { 943 struct rainfo *rai; 944 u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; 945 union nd_opts ndopts; 946 char *on_off[] = {"OFF", "ON"}; 947 u_int32_t reachabletime, retranstimer, mtu; 948 int inconsistent = 0; 949 950 syslog(LOG_DEBUG, 951 "<%s> RA received from %s on %s", 952 __func__, 953 inet_ntop(AF_INET6, &from->sin6_addr, 954 ntopbuf, INET6_ADDRSTRLEN), 955 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 956 957 /* ND option check */ 958 memset(&ndopts, 0, sizeof(ndopts)); 959 if (nd6_options((struct nd_opt_hdr *)(ra + 1), 960 len - sizeof(struct nd_router_advert), 961 &ndopts, NDOPT_FLAG_SRCLINKADDR | 962 NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU)) { 963 syslog(LOG_INFO, 964 "<%s> ND option check failed for an RA from %s on %s", 965 __func__, 966 inet_ntop(AF_INET6, &from->sin6_addr, 967 ntopbuf, INET6_ADDRSTRLEN), 968 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 969 return; 970 } 971 972 /* 973 * RA consistency check according to RFC-2461 6.2.7 974 */ 975 if ((rai = if_indextorainfo(pi->ipi6_ifindex)) == 0) { 976 syslog(LOG_INFO, 977 "<%s> received RA from %s on non-advertising" 978 " interface(%s)", 979 __func__, 980 inet_ntop(AF_INET6, &from->sin6_addr, 981 ntopbuf, INET6_ADDRSTRLEN), 982 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 983 goto done; 984 } 985 rai->rainput++; /* increment statistics */ 986 987 /* Cur Hop Limit value */ 988 if (ra->nd_ra_curhoplimit && rai->hoplimit && 989 ra->nd_ra_curhoplimit != rai->hoplimit) { 990 syslog(LOG_INFO, 991 "<%s> CurHopLimit inconsistent on %s:" 992 " %d from %s, %d from us", 993 __func__, 994 rai->ifname, 995 ra->nd_ra_curhoplimit, 996 inet_ntop(AF_INET6, &from->sin6_addr, 997 ntopbuf, INET6_ADDRSTRLEN), 998 rai->hoplimit); 999 inconsistent++; 1000 } 1001 /* M flag */ 1002 if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) != 1003 rai->managedflg) { 1004 syslog(LOG_INFO, 1005 "<%s> M flag inconsistent on %s:" 1006 " %s from %s, %s from us", 1007 __func__, 1008 rai->ifname, 1009 on_off[!rai->managedflg], 1010 inet_ntop(AF_INET6, &from->sin6_addr, 1011 ntopbuf, INET6_ADDRSTRLEN), 1012 on_off[rai->managedflg]); 1013 inconsistent++; 1014 } 1015 /* O flag */ 1016 if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) != 1017 rai->otherflg) { 1018 syslog(LOG_INFO, 1019 "<%s> O flag inconsistent on %s:" 1020 " %s from %s, %s from us", 1021 __func__, 1022 rai->ifname, 1023 on_off[!rai->otherflg], 1024 inet_ntop(AF_INET6, &from->sin6_addr, 1025 ntopbuf, INET6_ADDRSTRLEN), 1026 on_off[rai->otherflg]); 1027 inconsistent++; 1028 } 1029 /* Reachable Time */ 1030 reachabletime = ntohl(ra->nd_ra_reachable); 1031 if (reachabletime && rai->reachabletime && 1032 reachabletime != rai->reachabletime) { 1033 syslog(LOG_INFO, 1034 "<%s> ReachableTime inconsistent on %s:" 1035 " %d from %s, %d from us", 1036 __func__, 1037 rai->ifname, 1038 reachabletime, 1039 inet_ntop(AF_INET6, &from->sin6_addr, 1040 ntopbuf, INET6_ADDRSTRLEN), 1041 rai->reachabletime); 1042 inconsistent++; 1043 } 1044 /* Retrans Timer */ 1045 retranstimer = ntohl(ra->nd_ra_retransmit); 1046 if (retranstimer && rai->retranstimer && 1047 retranstimer != rai->retranstimer) { 1048 syslog(LOG_INFO, 1049 "<%s> RetranceTimer inconsistent on %s:" 1050 " %d from %s, %d from us", 1051 __func__, 1052 rai->ifname, 1053 retranstimer, 1054 inet_ntop(AF_INET6, &from->sin6_addr, 1055 ntopbuf, INET6_ADDRSTRLEN), 1056 rai->retranstimer); 1057 inconsistent++; 1058 } 1059 /* Values in the MTU options */ 1060 if (ndopts.nd_opts_mtu) { 1061 mtu = ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 1062 if (mtu && rai->linkmtu && mtu != rai->linkmtu) { 1063 syslog(LOG_INFO, 1064 "<%s> MTU option value inconsistent on %s:" 1065 " %d from %s, %d from us", 1066 __func__, 1067 rai->ifname, mtu, 1068 inet_ntop(AF_INET6, &from->sin6_addr, 1069 ntopbuf, INET6_ADDRSTRLEN), 1070 rai->linkmtu); 1071 inconsistent++; 1072 } 1073 } 1074 /* Preferred and Valid Lifetimes for prefixes */ 1075 { 1076 struct nd_optlist *optp = ndopts.nd_opts_list; 1077 1078 if (ndopts.nd_opts_pi) { 1079 if (prefix_check(ndopts.nd_opts_pi, rai, from)) 1080 inconsistent++; 1081 } 1082 while (optp) { 1083 if (prefix_check((struct nd_opt_prefix_info *)optp->opt, 1084 rai, from)) 1085 inconsistent++; 1086 optp = optp->next; 1087 } 1088 } 1089 1090 if (inconsistent) 1091 rai->rainconsistent++; 1092 1093 done: 1094 free_ndopts(&ndopts); 1095 return; 1096 } 1097 1098 /* return a non-zero value if the received prefix is inconsitent with ours */ 1099 static int 1100 prefix_check(struct nd_opt_prefix_info *pinfo, 1101 struct rainfo *rai, struct sockaddr_in6 *from) 1102 { 1103 u_int32_t preferred_time, valid_time; 1104 struct prefix *pp; 1105 int inconsistent = 0; 1106 u_char ntopbuf[INET6_ADDRSTRLEN], prefixbuf[INET6_ADDRSTRLEN]; 1107 struct timeval now; 1108 1109 #if 0 /* impossible */ 1110 if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION) 1111 return(0); 1112 #endif 1113 1114 /* 1115 * log if the adveritsed prefix has link-local scope(sanity check?) 1116 */ 1117 if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) { 1118 syslog(LOG_INFO, 1119 "<%s> link-local prefix %s/%d is advertised " 1120 "from %s on %s", 1121 __func__, 1122 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, 1123 prefixbuf, INET6_ADDRSTRLEN), 1124 pinfo->nd_opt_pi_prefix_len, 1125 inet_ntop(AF_INET6, &from->sin6_addr, 1126 ntopbuf, INET6_ADDRSTRLEN), 1127 rai->ifname); 1128 } 1129 1130 if ((pp = find_prefix(rai, &pinfo->nd_opt_pi_prefix, 1131 pinfo->nd_opt_pi_prefix_len)) == NULL) { 1132 syslog(LOG_INFO, 1133 "<%s> prefix %s/%d from %s on %s is not in our list", 1134 __func__, 1135 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, 1136 prefixbuf, INET6_ADDRSTRLEN), 1137 pinfo->nd_opt_pi_prefix_len, 1138 inet_ntop(AF_INET6, &from->sin6_addr, 1139 ntopbuf, INET6_ADDRSTRLEN), 1140 rai->ifname); 1141 return(0); 1142 } 1143 1144 preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time); 1145 if (pp->pltimeexpire) { 1146 /* 1147 * The lifetime is decremented in real time, so we should 1148 * compare the expiration time. 1149 * (RFC 2461 Section 6.2.7.) 1150 * XXX: can we really expect that all routers on the link 1151 * have synchronized clocks? 1152 */ 1153 gettimeofday(&now, NULL); 1154 preferred_time += now.tv_sec; 1155 1156 if (!pp->timer && rai->clockskew && 1157 abs(preferred_time - pp->pltimeexpire) > rai->clockskew) { 1158 syslog(LOG_INFO, 1159 "<%s> preferred lifetime for %s/%d" 1160 " (decr. in real time) inconsistent on %s:" 1161 " %d from %s, %ld from us", 1162 __func__, 1163 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, 1164 prefixbuf, INET6_ADDRSTRLEN), 1165 pinfo->nd_opt_pi_prefix_len, 1166 rai->ifname, preferred_time, 1167 inet_ntop(AF_INET6, &from->sin6_addr, 1168 ntopbuf, INET6_ADDRSTRLEN), 1169 pp->pltimeexpire); 1170 inconsistent++; 1171 } 1172 } else if (!pp->timer && preferred_time != pp->preflifetime) { 1173 syslog(LOG_INFO, 1174 "<%s> preferred lifetime for %s/%d" 1175 " inconsistent on %s:" 1176 " %d from %s, %d from us", 1177 __func__, 1178 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, 1179 prefixbuf, INET6_ADDRSTRLEN), 1180 pinfo->nd_opt_pi_prefix_len, 1181 rai->ifname, preferred_time, 1182 inet_ntop(AF_INET6, &from->sin6_addr, 1183 ntopbuf, INET6_ADDRSTRLEN), 1184 pp->preflifetime); 1185 } 1186 1187 valid_time = ntohl(pinfo->nd_opt_pi_valid_time); 1188 if (pp->vltimeexpire) { 1189 gettimeofday(&now, NULL); 1190 valid_time += now.tv_sec; 1191 1192 if (!pp->timer && rai->clockskew && 1193 abs(valid_time - pp->vltimeexpire) > rai->clockskew) { 1194 syslog(LOG_INFO, 1195 "<%s> valid lifetime for %s/%d" 1196 " (decr. in real time) inconsistent on %s:" 1197 " %d from %s, %ld from us", 1198 __func__, 1199 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, 1200 prefixbuf, INET6_ADDRSTRLEN), 1201 pinfo->nd_opt_pi_prefix_len, 1202 rai->ifname, preferred_time, 1203 inet_ntop(AF_INET6, &from->sin6_addr, 1204 ntopbuf, INET6_ADDRSTRLEN), 1205 pp->vltimeexpire); 1206 inconsistent++; 1207 } 1208 } else if (!pp->timer && valid_time != pp->validlifetime) { 1209 syslog(LOG_INFO, 1210 "<%s> valid lifetime for %s/%d" 1211 " inconsistent on %s:" 1212 " %d from %s, %d from us", 1213 __func__, 1214 inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix, 1215 prefixbuf, INET6_ADDRSTRLEN), 1216 pinfo->nd_opt_pi_prefix_len, 1217 rai->ifname, valid_time, 1218 inet_ntop(AF_INET6, &from->sin6_addr, 1219 ntopbuf, INET6_ADDRSTRLEN), 1220 pp->validlifetime); 1221 inconsistent++; 1222 } 1223 1224 return(inconsistent); 1225 } 1226 1227 struct prefix * 1228 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen) 1229 { 1230 struct prefix *pp; 1231 int bytelen, bitlen; 1232 u_char bitmask; 1233 1234 for (pp = rai->prefix.next; pp != &rai->prefix; pp = pp->next) { 1235 if (plen != pp->prefixlen) 1236 continue; 1237 bytelen = plen / 8; 1238 bitlen = plen % 8; 1239 bitmask = 0xff << (8 - bitlen); 1240 if (memcmp((void *)prefix, (void *)&pp->prefix, bytelen)) 1241 continue; 1242 if (bitlen == 0 || 1243 ((prefix->s6_addr[bytelen] & bitmask) == 1244 (pp->prefix.s6_addr[bytelen] & bitmask))) { 1245 return(pp); 1246 } 1247 } 1248 1249 return(NULL); 1250 } 1251 1252 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */ 1253 int 1254 prefix_match(struct in6_addr *p0, int plen0, 1255 struct in6_addr *p1, int plen1) 1256 { 1257 int bytelen, bitlen; 1258 u_char bitmask; 1259 1260 if (plen0 < plen1) 1261 return(0); 1262 bytelen = plen1 / 8; 1263 bitlen = plen1 % 8; 1264 bitmask = 0xff << (8 - bitlen); 1265 if (memcmp((void *)p0, (void *)p1, bytelen)) 1266 return(0); 1267 if (bitlen == 0 || 1268 ((p0->s6_addr[bytelen] & bitmask) == 1269 (p1->s6_addr[bytelen] & bitmask))) { 1270 return(1); 1271 } 1272 1273 return(0); 1274 } 1275 1276 static int 1277 nd6_options(struct nd_opt_hdr *hdr, int limit, 1278 union nd_opts *ndopts, u_int32_t optflags) 1279 { 1280 int optlen = 0; 1281 1282 for (; limit > 0; limit -= optlen) { 1283 if (limit < sizeof(struct nd_opt_hdr)) { 1284 syslog(LOG_INFO, "<%s> short option header", __func__); 1285 goto bad; 1286 } 1287 1288 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen); 1289 if (hdr->nd_opt_len == 0) { 1290 syslog(LOG_INFO, 1291 "<%s> bad ND option length(0) (type = %d)", 1292 __func__, hdr->nd_opt_type); 1293 goto bad; 1294 } 1295 optlen = hdr->nd_opt_len << 3; 1296 if (optlen > limit) { 1297 syslog(LOG_INFO, "<%s> short option", __func__); 1298 goto bad; 1299 } 1300 1301 if (hdr->nd_opt_type > ND_OPT_MTU) { 1302 syslog(LOG_INFO, "<%s> unknown ND option(type %d)", 1303 __func__, hdr->nd_opt_type); 1304 continue; 1305 } 1306 1307 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) { 1308 syslog(LOG_INFO, "<%s> unexpected ND option(type %d)", 1309 __func__, hdr->nd_opt_type); 1310 continue; 1311 } 1312 1313 /* 1314 * Option length check. Do it here for all fixed-length 1315 * options. 1316 */ 1317 if ((hdr->nd_opt_type == ND_OPT_MTU && 1318 (optlen != sizeof(struct nd_opt_mtu))) || 1319 ((hdr->nd_opt_type == ND_OPT_PREFIX_INFORMATION && 1320 optlen != sizeof(struct nd_opt_prefix_info)))) { 1321 syslog(LOG_INFO, "<%s> invalid option length", 1322 __func__); 1323 continue; 1324 } 1325 1326 switch (hdr->nd_opt_type) { 1327 case ND_OPT_TARGET_LINKADDR: 1328 case ND_OPT_REDIRECTED_HEADER: 1329 break; /* we don't care about these options */ 1330 case ND_OPT_SOURCE_LINKADDR: 1331 case ND_OPT_MTU: 1332 if (ndopts->nd_opt_array[hdr->nd_opt_type]) { 1333 syslog(LOG_INFO, 1334 "<%s> duplicated ND option (type = %d)", 1335 __func__, hdr->nd_opt_type); 1336 } 1337 ndopts->nd_opt_array[hdr->nd_opt_type] = hdr; 1338 break; 1339 case ND_OPT_PREFIX_INFORMATION: 1340 { 1341 struct nd_optlist *pfxlist; 1342 1343 if (ndopts->nd_opts_pi == 0) { 1344 ndopts->nd_opts_pi = 1345 (struct nd_opt_prefix_info *)hdr; 1346 continue; 1347 } 1348 if ((pfxlist = malloc(sizeof(*pfxlist))) == NULL) { 1349 syslog(LOG_ERR, "<%s> can't allocate memory", 1350 __func__); 1351 goto bad; 1352 } 1353 pfxlist->next = ndopts->nd_opts_list; 1354 pfxlist->opt = hdr; 1355 ndopts->nd_opts_list = pfxlist; 1356 1357 break; 1358 } 1359 default: /* impossible */ 1360 break; 1361 } 1362 } 1363 1364 return(0); 1365 1366 bad: 1367 free_ndopts(ndopts); 1368 1369 return(-1); 1370 } 1371 1372 static void 1373 free_ndopts(union nd_opts *ndopts) 1374 { 1375 struct nd_optlist *opt = ndopts->nd_opts_list, *next; 1376 1377 while (opt) { 1378 next = opt->next; 1379 free(opt); 1380 opt = next; 1381 } 1382 } 1383 1384 void 1385 sock_open() 1386 { 1387 struct icmp6_filter filt; 1388 struct ipv6_mreq mreq; 1389 struct rainfo *ra = ralist; 1390 int on; 1391 /* XXX: should be max MTU attached to the node */ 1392 static u_char answer[1500]; 1393 1394 rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1395 CMSG_SPACE(sizeof(int)); 1396 rcvcmsgbuf = (u_char *)malloc(rcvcmsgbuflen); 1397 if (rcvcmsgbuf == NULL) { 1398 syslog(LOG_ERR, "<%s> not enough core", __func__); 1399 exit(1); 1400 } 1401 1402 sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 1403 CMSG_SPACE(sizeof(int)); 1404 sndcmsgbuf = (u_char *)malloc(sndcmsgbuflen); 1405 if (sndcmsgbuf == NULL) { 1406 syslog(LOG_ERR, "<%s> not enough core", __func__); 1407 exit(1); 1408 } 1409 1410 if ((sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) { 1411 syslog(LOG_ERR, "<%s> socket: %s", __func__, 1412 strerror(errno)); 1413 exit(1); 1414 } 1415 1416 /* specify to tell receiving interface */ 1417 on = 1; 1418 #ifdef IPV6_RECVPKTINFO 1419 if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 1420 sizeof(on)) < 0) { 1421 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s", 1422 __func__, strerror(errno)); 1423 exit(1); 1424 } 1425 #else /* old adv. API */ 1426 if (setsockopt(sock, IPPROTO_IPV6, IPV6_PKTINFO, &on, 1427 sizeof(on)) < 0) { 1428 syslog(LOG_ERR, "<%s> IPV6_PKTINFO: %s", 1429 __func__, strerror(errno)); 1430 exit(1); 1431 } 1432 #endif 1433 1434 on = 1; 1435 /* specify to tell value of hoplimit field of received IP6 hdr */ 1436 #ifdef IPV6_RECVHOPLIMIT 1437 if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 1438 sizeof(on)) < 0) { 1439 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s", 1440 __func__, strerror(errno)); 1441 exit(1); 1442 } 1443 #else /* old adv. API */ 1444 if (setsockopt(sock, IPPROTO_IPV6, IPV6_HOPLIMIT, &on, 1445 sizeof(on)) < 0) { 1446 syslog(LOG_ERR, "<%s> IPV6_HOPLIMIT: %s", 1447 __func__, strerror(errno)); 1448 exit(1); 1449 } 1450 #endif 1451 1452 ICMP6_FILTER_SETBLOCKALL(&filt); 1453 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt); 1454 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt); 1455 if (accept_rr) 1456 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt); 1457 if (setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, 1458 sizeof(filt)) < 0) { 1459 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s", 1460 __func__, strerror(errno)); 1461 exit(1); 1462 } 1463 1464 /* 1465 * join all routers multicast address on each advertising interface. 1466 */ 1467 if (inet_pton(AF_INET6, ALLROUTERS_LINK, 1468 &mreq.ipv6mr_multiaddr.s6_addr) 1469 != 1) { 1470 syslog(LOG_ERR, "<%s> inet_pton failed(library bug?)", 1471 __func__); 1472 exit(1); 1473 } 1474 while (ra) { 1475 mreq.ipv6mr_interface = ra->ifindex; 1476 if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq, 1477 sizeof(mreq)) < 0) { 1478 syslog(LOG_ERR, "<%s> IPV6_JOIN_GROUP(link) on %s: %s", 1479 __func__, ra->ifname, strerror(errno)); 1480 exit(1); 1481 } 1482 ra = ra->next; 1483 } 1484 1485 /* 1486 * When attending router renumbering, join all-routers site-local 1487 * multicast group. 1488 */ 1489 if (accept_rr) { 1490 if (inet_pton(AF_INET6, ALLROUTERS_SITE, 1491 &in6a_site_allrouters) != 1) { 1492 syslog(LOG_ERR, "<%s> inet_pton failed(library bug?)", 1493 __func__); 1494 exit(1); 1495 } 1496 mreq.ipv6mr_multiaddr = in6a_site_allrouters; 1497 if (mcastif) { 1498 if ((mreq.ipv6mr_interface = if_nametoindex(mcastif)) 1499 == 0) { 1500 syslog(LOG_ERR, 1501 "<%s> invalid interface: %s", 1502 __func__, mcastif); 1503 exit(1); 1504 } 1505 } else 1506 mreq.ipv6mr_interface = ralist->ifindex; 1507 if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP, 1508 &mreq, sizeof(mreq)) < 0) { 1509 syslog(LOG_ERR, 1510 "<%s> IPV6_JOIN_GROUP(site) on %s: %s", 1511 __func__, 1512 mcastif ? mcastif : ralist->ifname, 1513 strerror(errno)); 1514 exit(1); 1515 } 1516 } 1517 1518 /* initialize msghdr for receiving packets */ 1519 rcviov[0].iov_base = (caddr_t)answer; 1520 rcviov[0].iov_len = sizeof(answer); 1521 rcvmhdr.msg_name = (caddr_t)&rcvfrom; 1522 rcvmhdr.msg_namelen = sizeof(rcvfrom); 1523 rcvmhdr.msg_iov = rcviov; 1524 rcvmhdr.msg_iovlen = 1; 1525 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf; 1526 rcvmhdr.msg_controllen = rcvcmsgbuflen; 1527 1528 /* initialize msghdr for sending packets */ 1529 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6); 1530 sndmhdr.msg_iov = sndiov; 1531 sndmhdr.msg_iovlen = 1; 1532 sndmhdr.msg_control = (caddr_t)sndcmsgbuf; 1533 sndmhdr.msg_controllen = sndcmsgbuflen; 1534 1535 return; 1536 } 1537 1538 /* open a routing socket to watch the routing table */ 1539 static void 1540 rtsock_open() 1541 { 1542 if ((rtsock = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) { 1543 syslog(LOG_ERR, 1544 "<%s> socket: %s", __func__, strerror(errno)); 1545 exit(1); 1546 } 1547 } 1548 1549 struct rainfo * 1550 if_indextorainfo(int idx) 1551 { 1552 struct rainfo *rai = ralist; 1553 1554 for (rai = ralist; rai; rai = rai->next) { 1555 if (rai->ifindex == idx) 1556 return(rai); 1557 } 1558 1559 return(NULL); /* search failed */ 1560 } 1561 1562 static void 1563 ra_output(rainfo) 1564 struct rainfo *rainfo; 1565 { 1566 int i; 1567 struct cmsghdr *cm; 1568 struct in6_pktinfo *pi; 1569 struct soliciter *sol, *nextsol; 1570 1571 if ((iflist[rainfo->ifindex]->ifm_flags & IFF_UP) == 0) { 1572 syslog(LOG_DEBUG, "<%s> %s is not up, skip sending RA", 1573 __func__, rainfo->ifname); 1574 return; 1575 } 1576 1577 make_packet(rainfo); /* XXX: inefficient */ 1578 1579 sndmhdr.msg_name = (caddr_t)&sin6_allnodes; 1580 sndmhdr.msg_iov[0].iov_base = (caddr_t)rainfo->ra_data; 1581 sndmhdr.msg_iov[0].iov_len = rainfo->ra_datalen; 1582 1583 cm = CMSG_FIRSTHDR(&sndmhdr); 1584 /* specify the outgoing interface */ 1585 cm->cmsg_level = IPPROTO_IPV6; 1586 cm->cmsg_type = IPV6_PKTINFO; 1587 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); 1588 pi = (struct in6_pktinfo *)CMSG_DATA(cm); 1589 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/ 1590 pi->ipi6_ifindex = rainfo->ifindex; 1591 1592 /* specify the hop limit of the packet */ 1593 { 1594 int hoplimit = 255; 1595 1596 cm = CMSG_NXTHDR(&sndmhdr, cm); 1597 cm->cmsg_level = IPPROTO_IPV6; 1598 cm->cmsg_type = IPV6_HOPLIMIT; 1599 cm->cmsg_len = CMSG_LEN(sizeof(int)); 1600 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int)); 1601 } 1602 1603 syslog(LOG_DEBUG, 1604 "<%s> send RA on %s, # of waitings = %d", 1605 __func__, rainfo->ifname, rainfo->waiting); 1606 1607 i = sendmsg(sock, &sndmhdr, 0); 1608 1609 if (i < 0 || i != rainfo->ra_datalen) { 1610 if (i < 0) { 1611 syslog(LOG_ERR, "<%s> sendmsg on %s: %s", 1612 __func__, rainfo->ifname, 1613 strerror(errno)); 1614 } 1615 } 1616 /* update counter */ 1617 if (rainfo->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS) 1618 rainfo->initcounter++; 1619 rainfo->raoutput++; 1620 1621 /* 1622 * unicast advertisements 1623 * XXX commented out. reason: though spec does not forbit it, unicast 1624 * advert does not really help 1625 */ 1626 for (sol = rainfo->soliciter; sol; sol = nextsol) { 1627 nextsol = sol->next; 1628 1629 sol->next = NULL; 1630 free(sol); 1631 } 1632 rainfo->soliciter = NULL; 1633 1634 /* update timestamp */ 1635 gettimeofday(&rainfo->lastsent, NULL); 1636 1637 /* reset waiting conter */ 1638 rainfo->waiting = 0; 1639 } 1640 1641 /* process RA timer */ 1642 struct rtadvd_timer * 1643 ra_timeout(void *data) 1644 { 1645 struct rainfo *rai = (struct rainfo *)data; 1646 1647 #ifdef notyet 1648 /* if necessary, reconstruct the packet. */ 1649 #endif 1650 1651 syslog(LOG_DEBUG, 1652 "<%s> RA timer on %s is expired", 1653 __func__, rai->ifname); 1654 1655 ra_output(rai); 1656 1657 return(rai->timer); 1658 } 1659 1660 /* update RA timer */ 1661 void 1662 ra_timer_update(void *data, struct timeval *tm) 1663 { 1664 struct rainfo *rai = (struct rainfo *)data; 1665 long interval; 1666 1667 /* 1668 * Whenever a multicast advertisement is sent from an interface, 1669 * the timer is reset to a uniformly-distributed random value 1670 * between the interface's configured MinRtrAdvInterval and 1671 * MaxRtrAdvInterval (RFC2461 6.2.4). 1672 */ 1673 interval = rai->mininterval; 1674 #ifdef HAVE_ARC4RANDOM 1675 interval += arc4random_uniform(rai->maxinterval - rai->mininterval); 1676 #else 1677 interval += random() % (rai->maxinterval - rai->mininterval); 1678 #endif 1679 1680 /* 1681 * For the first few advertisements (up to 1682 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen interval 1683 * is greater than MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer 1684 * SHOULD be set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead. 1685 * (RFC-2461 6.2.4) 1686 */ 1687 if (rai->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS && 1688 interval > MAX_INITIAL_RTR_ADVERT_INTERVAL) 1689 interval = MAX_INITIAL_RTR_ADVERT_INTERVAL; 1690 1691 tm->tv_sec = interval; 1692 tm->tv_usec = 0; 1693 1694 syslog(LOG_DEBUG, 1695 "<%s> RA timer on %s is set to %ld:%ld", 1696 __func__, rai->ifname, 1697 (long int)tm->tv_sec, (long int)tm->tv_usec); 1698 1699 return; 1700 } 1701