usr.sbin/rtadvd/rtadvd.c

   1 /*      $FreeBSD$       */
   2 /*      $KAME: rtadvd.c,v 1.50 2001/02/04 06:15:15 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 <stdlib.h>
  53 #include <err.h>
  54 #include <errno.h>
  55 #include <string.h>
  56 #include <stdlib.h>
  57 #include <syslog.h>
  58 #include "rtadvd.h"
  59 #include "rrenum.h"
  60 #include "advcap.h"
  61 #include "timer.h"
  62 #include "if.h"
  63 #include "config.h"
  64 #include "dump.h"
  65
  66 struct msghdr rcvmhdr;
  67 static u_char *rcvcmsgbuf;
  68 static size_t rcvcmsgbuflen;
  69 static u_char *sndcmsgbuf = NULL;
  70 static size_t sndcmsgbuflen;
  71 static int do_dump;
  72 static int do_die;
  73 struct msghdr sndmhdr;
  74 struct iovec rcviov[2];
  75 struct iovec sndiov[2];
  76 struct sockaddr_in6 from;
  77 struct sockaddr_in6 sin6_allnodes = {sizeof(sin6_allnodes), AF_INET6};
  78 struct in6_addr in6a_site_allrouters;
  79 static char *dumpfilename = "/var/run/rtadvd.dump"; /* XXX: should be configurable */
  80 static char *pidfilename = "/var/run/rtadvd.pid"; /* should be configurable */
  81 static char *mcastif;
  82 int sock;
  83 int rtsock = -1;
  84 #ifdef MIP6
  85 int mobileip6 = 0;
  86 #endif
  87 int accept_rr = 0;
  88 int dflag = 0, sflag = 0;
  89
  90 u_char *conffile = NULL;
  91
  92 struct rainfo *ralist = NULL;
  93 struct nd_optlist {
  94         struct nd_optlist *next;
  95         struct nd_opt_hdr *opt;
  96 };
  97 union nd_opts {
  98         struct nd_opt_hdr *nd_opt_array[7];
  99         struct {
 100                 struct nd_opt_hdr *zero;
 101                 struct nd_opt_hdr *src_lladdr;
 102                 struct nd_opt_hdr *tgt_lladdr;
 103                 struct nd_opt_prefix_info *pi;
 104                 struct nd_opt_rd_hdr *rh;
 105                 struct nd_opt_mtu *mtu;
 106                 struct nd_optlist *list;
 107         } nd_opt_each;
 108 };
 109 #define nd_opts_src_lladdr      nd_opt_each.src_lladdr
 110 #define nd_opts_tgt_lladdr      nd_opt_each.tgt_lladdr
 111 #define nd_opts_pi              nd_opt_each.pi
 112 #define nd_opts_rh              nd_opt_each.rh
 113 #define nd_opts_mtu             nd_opt_each.mtu
 114 #define nd_opts_list            nd_opt_each.list
 115
 116 #define NDOPT_FLAG_SRCLINKADDR 0x1
 117 #define NDOPT_FLAG_TGTLINKADDR 0x2
 118 #define NDOPT_FLAG_PREFIXINFO 0x4
 119 #define NDOPT_FLAG_RDHDR 0x8
 120 #define NDOPT_FLAG_MTU 0x10
 121
 122 u_int32_t ndopt_flags[] = {
 123         0, NDOPT_FLAG_SRCLINKADDR, NDOPT_FLAG_TGTLINKADDR,
 124         NDOPT_FLAG_PREFIXINFO, NDOPT_FLAG_RDHDR, NDOPT_FLAG_MTU
 125 };
 126
 127 int main __P((int, char *[]));
 128 static void set_die __P((int));
 129 static void die __P((void));
 130 static void sock_open __P((void));
 131 static void rtsock_open __P((void));
 132 static void rtadvd_input __P((void));
 133 static void rs_input __P((int, struct nd_router_solicit *,
 134                           struct in6_pktinfo *, struct sockaddr_in6 *));
 135 static void ra_input __P((int, struct nd_router_advert *,
 136                           struct in6_pktinfo *, struct sockaddr_in6 *));
 137 static int prefix_check __P((struct nd_opt_prefix_info *, struct rainfo *,
 138                              struct sockaddr_in6 *));
 139 static int nd6_options __P((struct nd_opt_hdr *, int,
 140                             union nd_opts *, u_int32_t));
 141 static void free_ndopts __P((union nd_opts *));
 142 static void ra_output __P((struct rainfo *));
 143 static void rtmsg_input __P((void));
 144 static void rtadvd_set_dump_file __P((void));
 145
 146 int
 147 main(argc, argv)
 148         int argc;
 149         char *argv[];
 150 {
 151         fd_set fdset;
 152         int maxfd = 0;
 153         struct timeval *timeout;
 154         int i, ch;
 155         int fflag = 0;
 156         FILE *pidfp;
 157         pid_t pid;
 158
 159         openlog("rtadvd", LOG_NDELAY|LOG_PID, LOG_DAEMON);
 160
 161         /* get command line options and arguments */
 162 #ifdef MIP6
 163 #define OPTIONS "c:dDfM:mRs"
 164 #else
 165 #define OPTIONS "c:dDfM:Rs"
 166 #endif
 167         while ((ch = getopt(argc, argv, OPTIONS)) != -1) {
 168 #undef OPTIONS
 169                 switch (ch) {
 170                 case 'c':
 171                         conffile = optarg;
 172                         break;
 173                 case 'd':
 174                         dflag = 1;
 175                         break;
 176                 case 'D':
 177                         dflag = 2;
 178                         break;
 179                 case 'f':
 180                         fflag = 1;
 181                         break;
 182                 case 'M':
 183                         mcastif = optarg;
 184                         break;
 185 #ifdef MIP6
 186                 case 'm':
 187                         mobileip6 = 1;
 188                         break;
 189 #endif
 190                 case 'R':
 191                         fprintf(stderr, "rtadvd: "
 192                                 "the -R option is currently ignored.\n");
 193                         /* accept_rr = 1; */
 194                         /* run anyway... */
 195                         break;
 196                 case 's':
 197                         sflag = 1;
 198                         break;
 199                 }
 200         }
 201         argc -= optind;
 202         argv += optind;
 203         if (argc == 0) {
 204                 fprintf(stderr,
 205 #ifdef MIP6
 206                         "usage: rtadvd [-dDfMmRs] [-c conffile] "
 207 #else
 208                         "usage: rtadvd [-dDfMRs] [-c conffile] "
 209 #endif
 210                         "interfaces...\n");
 211                 exit(1);
 212         }
 213
 214         /* set log level */
 215         if (dflag == 0)
 216                 (void)setlogmask(LOG_UPTO(LOG_ERR));
 217         if (dflag == 1)
 218                 (void)setlogmask(LOG_UPTO(LOG_INFO));
 219
 220         /* timer initialization */
 221         rtadvd_timer_init();
 222
 223         /* random value initialization */
 224         srandom((u_long)time(NULL));
 225
 226         /* get iflist block from kernel */
 227         init_iflist();
 228
 229         while (argc--)
 230                 getconfig(*argv++);
 231
 232         if (inet_pton(AF_INET6, ALLNODES, &sin6_allnodes.sin6_addr) != 1) {
 233                 fprintf(stderr, "fatal: inet_pton failed\n");
 234                 exit(1);
 235         }
 236         sock_open();
 237
 238         if (!fflag)
 239                 daemon(1, 0);
 240
 241         /* record the current PID */
 242         pid = getpid();
 243         if ((pidfp = fopen(pidfilename, "w")) == NULL) {
 244                 syslog(LOG_ERR,
 245                     "<%s> failed to open a log file(%s), run anyway.",
 246                     __FUNCTION__, pidfilename);
 247         } else {
 248                 fprintf(pidfp, "%d\n", pid);
 249                 fclose(pidfp);
 250         }
 251
 252         FD_ZERO(&fdset);
 253         FD_SET(sock, &fdset);
 254         maxfd = sock;
 255         if (sflag == 0) {
 256                 rtsock_open();
 257                 FD_SET(rtsock, &fdset);
 258                 if (rtsock > sock)
 259                         maxfd = rtsock;
 260         } else
 261                 rtsock = -1;
 262
 263         signal(SIGTERM, (void *)set_die);
 264         signal(SIGUSR1, (void *)rtadvd_set_dump_file);
 265
 266         while (1) {
 267                 struct fd_set select_fd = fdset; /* reinitialize */
 268
 269                 if (do_dump) {  /* SIGUSR1 */
 270                         do_dump = 0;
 271                         rtadvd_dump_file(dumpfilename);
 272                 }
 273
 274                 if (do_die) {
 275                         die();
 276                         /*NOTREACHED*/
 277                 }
 278
 279                 /* timer expiration check and reset the timer */
 280                 timeout = rtadvd_check_timer();
 281
 282                 if (timeout != NULL) {
 283                         syslog(LOG_DEBUG,
 284                             "<%s> set timer to %ld:%ld. waiting for "
 285                             "inputs or timeout", __FUNCTION__,
 286                             (long int)timeout->tv_sec,
 287                             (long int)timeout->tv_usec);
 288                 } else {
 289                         syslog(LOG_DEBUG,
 290                             "<%s> there's no timer. waiting for inputs",
 291                             __FUNCTION__);
 292                 }
 293
 294                 if ((i = select(maxfd + 1, &select_fd,
 295                                 NULL, NULL, timeout)) < 0) {
 296                         /* EINTR would occur upon SIGUSR1 for status dump */
 297                         if (errno != EINTR)
 298                                 syslog(LOG_ERR, "<%s> select: %s",
 299                                     __FUNCTION__, strerror(errno));
 300                         continue;
 301                 }
 302                 if (i == 0)     /* timeout */
 303                         continue;
 304                 if (rtsock != -1 && FD_ISSET(rtsock, &select_fd))
 305                         rtmsg_input();
 306                 if (FD_ISSET(sock, &select_fd))
 307                         rtadvd_input();
 308         }
 309         exit(0);                /* NOTREACHED */
 310 }
 311
 312 static void
 313 rtadvd_set_dump_file()
 314 {
 315         do_dump = 1;
 316 }
 317
 318 static void
 319 set_die(sig)
 320         int sig;
 321 {
 322         do_die = 1;
 323 }
 324
 325 static void
 326 die()
 327 {
 328         struct rainfo *ra;
 329         int i;
 330         const int retrans = MAX_FINAL_RTR_ADVERTISEMENTS;
 331
 332         if (dflag > 1) {
 333                 syslog(LOG_DEBUG, "<%s> cease to be an advertising router\n",
 334                     __FUNCTION__);
 335         }
 336
 337         for (ra = ralist; ra; ra = ra->next) {
 338                 ra->lifetime = 0;
 339                 make_packet(ra);
 340         }
 341         for (i = 0; i < retrans; i++) {
 342                 for (ra = ralist; ra; ra = ra->next)
 343                         ra_output(ra);
 344                 sleep(MIN_DELAY_BETWEEN_RAS);
 345         }
 346         exit(0);
 347         /*NOTREACHED*/
 348 }
 349
 350 static void
 351 rtmsg_input()
 352 {
 353         int n, type, ifindex = 0, plen;
 354         size_t len;
 355         char msg[2048], *next, *lim;
 356         u_char ifname[IF_NAMESIZE];
 357         struct prefix *prefix;
 358         struct rainfo *rai;
 359         struct in6_addr *addr;
 360         char addrbuf[INET6_ADDRSTRLEN];
 361
 362         n = read(rtsock, msg, sizeof(msg));
 363         if (dflag > 1) {
 364                 syslog(LOG_DEBUG, "<%s> received a routing message "
 365                     "(type = %d, len = %d)", __FUNCTION__, rtmsg_type(msg), n);
 366         }
 367         if (n > rtmsg_len(msg)) {
 368                 /*
 369                  * This usually won't happen for messages received on
 370                  * a routing socket.
 371                  */
 372                 if (dflag > 1)
 373                         syslog(LOG_DEBUG,
 374                             "<%s> received data length is larger than "
 375                             "1st routing message len. multiple messages? "
 376                             "read %d bytes, but 1st msg len = %d",
 377                             __FUNCTION__, n, rtmsg_len(msg));
 378 #if 0
 379                 /* adjust length */
 380                 n = rtmsg_len(msg);
 381 #endif
 382         }
 383
 384         lim = msg + n;
 385         for (next = msg; next < lim; next += len) {
 386                 int oldifflags;
 387
 388                 next = get_next_msg(next, lim, 0, &len,
 389                                     RTADV_TYPE2BITMASK(RTM_ADD) |
 390                                     RTADV_TYPE2BITMASK(RTM_DELETE) |
 391                                     RTADV_TYPE2BITMASK(RTM_NEWADDR) |
 392                                     RTADV_TYPE2BITMASK(RTM_DELADDR) |
 393                                     RTADV_TYPE2BITMASK(RTM_IFINFO));
 394                 if (len == 0)
 395                         break;
 396                 type = rtmsg_type(next);
 397                 switch (type) {
 398                 case RTM_ADD:
 399                 case RTM_DELETE:
 400                         ifindex = get_rtm_ifindex(next);
 401                         break;
 402                 case RTM_NEWADDR:
 403                 case RTM_DELADDR:
 404                         ifindex = get_ifam_ifindex(next);
 405                         break;
 406                 case RTM_IFINFO:
 407                         ifindex = get_ifm_ifindex(next);
 408                         break;
 409                 default:
 410                         /* should not reach here */
 411                         if (dflag > 1) {
 412                                 syslog(LOG_DEBUG,
 413                                        "<%s:%d> unknown rtmsg %d on %s",
 414                                        __FUNCTION__, __LINE__, type,
 415                                        if_indextoname(ifindex, ifname));
 416                         }
 417                         continue;
 418                 }
 419
 420                 if ((rai = if_indextorainfo(ifindex)) == NULL) {
 421                         if (dflag > 1) {
 422                                 syslog(LOG_DEBUG,
 423                                        "<%s> route changed on "
 424                                        "non advertising interface(%s)",
 425                                        __FUNCTION__,
 426                                        if_indextoname(ifindex, ifname));
 427                         }
 428                         continue;
 429                 }
 430                 oldifflags = iflist[ifindex]->ifm_flags;
 431
 432                 switch (type) {
 433                 case RTM_ADD:
 434                         /* init ifflags because it may have changed */
 435                         iflist[ifindex]->ifm_flags =
 436                             if_getflags(ifindex, iflist[ifindex]->ifm_flags);
 437
 438                         if (sflag)
 439                                 break;  /* we aren't interested in prefixes  */
 440
 441                         addr = get_addr(msg);
 442                         plen = get_prefixlen(msg);
 443                         /* sanity check for plen */
 444                         /* as RFC2373, prefixlen is at least 4 */
 445                         if (plen < 4 || plen > 127) {
 446                                 syslog(LOG_INFO, "<%s> new interface route's"
 447                                     "plen %d is invalid for a prefix",
 448                                     __FUNCTION__, plen);
 449                                 break;
 450                         }
 451                         prefix = find_prefix(rai, addr, plen);
 452                         if (prefix) {
 453                                 if (dflag > 1) {
 454                                         syslog(LOG_DEBUG,
 455                                             "<%s> new prefix(%s/%d) "
 456                                             "added on %s, "
 457                                             "but it was already in list",
 458                                             __FUNCTION__,
 459                                             inet_ntop(AF_INET6, addr,
 460                                             (char *)addrbuf, INET6_ADDRSTRLEN),
 461                                             plen, rai->ifname);
 462                                 }
 463                                 break;
 464                         }
 465                         make_prefix(rai, ifindex, addr, plen);
 466                         break;
 467                 case RTM_DELETE:
 468                         /* init ifflags because it may have changed */
 469                         iflist[ifindex]->ifm_flags =
 470                             if_getflags(ifindex, iflist[ifindex]->ifm_flags);
 471
 472                         if (sflag)
 473                                 break;
 474
 475                         addr = get_addr(msg);
 476                         plen = get_prefixlen(msg);
 477                         /* sanity check for plen */
 478                         /* as RFC2373, prefixlen is at least 4 */
 479                         if (plen < 4 || plen > 127) {
 480                                 syslog(LOG_INFO,
 481                                     "<%s> deleted interface route's "
 482                                     "plen %d is invalid for a prefix",
 483                                     __FUNCTION__, plen);
 484                                 break;
 485                         }
 486                         prefix = find_prefix(rai, addr, plen);
 487                         if (prefix == NULL) {
 488                                 if (dflag > 1) {
 489                                         syslog(LOG_DEBUG,
 490                                             "<%s> prefix(%s/%d) was "
 491                                             "deleted on %s, "
 492                                             "but it was not in list",
 493                                             __FUNCTION__,
 494                                             inet_ntop(AF_INET6, addr,
 495                                             (char *)addrbuf, INET6_ADDRSTRLEN),
 496                                             plen, rai->ifname);
 497                                 }
 498                                 break;
 499                         }
 500                         delete_prefix(rai, prefix);
 501                         break;
 502                 case RTM_NEWADDR:
 503                 case RTM_DELADDR:
 504                         /* init ifflags because it may have changed */
 505                         iflist[ifindex]->ifm_flags =
 506                             if_getflags(ifindex, iflist[ifindex]->ifm_flags);
 507                         break;
 508                 case RTM_IFINFO:
 509                         iflist[ifindex]->ifm_flags = get_ifm_flags(next);
 510                         break;
 511                 default:
 512                         /* should not reach here */
 513                         if (dflag > 1) {
 514                                 syslog(LOG_DEBUG,
 515                                     "<%s:%d> unknown rtmsg %d on %s",
 516                                     __FUNCTION__, __LINE__, type,
 517                                     if_indextoname(ifindex, ifname));
 518                         }
 519                         return;
 520                 }
 521
 522                 /* check if an interface flag is changed */
 523                 if ((oldifflags & IFF_UP) != 0 &&       /* UP to DOWN */
 524                     (iflist[ifindex]->ifm_flags & IFF_UP) == 0) {
 525                         syslog(LOG_INFO,
 526                             "<%s> interface %s becomes down. stop timer.",
 527                             __FUNCTION__, rai->ifname);
 528                         rtadvd_remove_timer(&rai->timer);
 529                 } else if ((oldifflags & IFF_UP) == 0 &&        /* DOWN to UP */
 530                          (iflist[ifindex]->ifm_flags & IFF_UP) != 0) {
 531                         syslog(LOG_INFO,
 532                             "<%s> interface %s becomes up. restart timer.",
 533                             __FUNCTION__, rai->ifname);
 534
 535                         rai->initcounter = 0; /* reset the counter */
 536                         rai->waiting = 0; /* XXX */
 537                         rai->timer = rtadvd_add_timer(ra_timeout,
 538                             ra_timer_update, rai, rai);
 539                         ra_timer_update((void *)rai, &rai->timer->tm);
 540                         rtadvd_set_timer(&rai->timer->tm, rai->timer);
 541                 }
 542         }
 543
 544         return;
 545 }
 546
 547 void
 548 rtadvd_input()
 549 {
 550         int i;
 551         int *hlimp = NULL;
 552 #ifdef OLDRAWSOCKET
 553         struct ip6_hdr *ip;
 554 #endif
 555         struct icmp6_hdr *icp;
 556         int ifindex = 0;
 557         struct cmsghdr *cm;
 558         struct in6_pktinfo *pi = NULL;
 559         u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
 560         struct in6_addr dst = in6addr_any;
 561
 562         /*
 563          * Get message. We reset msg_controllen since the field could
 564          * be modified if we had received a message before setting
 565          * receive options.
 566          */
 567         rcvmhdr.msg_controllen = rcvcmsgbuflen;
 568         if ((i = recvmsg(sock, &rcvmhdr, 0)) < 0)
 569                 return;
 570
 571         /* extract optional information via Advanced API */
 572         for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr);
 573              cm;
 574              cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) {
 575                 if (cm->cmsg_level == IPPROTO_IPV6 &&
 576                     cm->cmsg_type == IPV6_PKTINFO &&
 577                     cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) {
 578                         pi = (struct in6_pktinfo *)(CMSG_DATA(cm));
 579                         ifindex = pi->ipi6_ifindex;
 580                         dst = pi->ipi6_addr;
 581                 }
 582                 if (cm->cmsg_level == IPPROTO_IPV6 &&
 583                     cm->cmsg_type == IPV6_HOPLIMIT &&
 584                     cm->cmsg_len == CMSG_LEN(sizeof(int)))
 585                         hlimp = (int *)CMSG_DATA(cm);
 586         }
 587         if (ifindex == 0) {
 588                 syslog(LOG_ERR,
 589                        "<%s> failed to get receiving interface",
 590                        __FUNCTION__);
 591                 return;
 592         }
 593         if (hlimp == NULL) {
 594                 syslog(LOG_ERR,
 595                        "<%s> failed to get receiving hop limit",
 596                        __FUNCTION__);
 597                 return;
 598         }
 599
 600         /*
 601          * If we happen to receive data on an interface which is now down,
 602          * just discard the data.
 603          */
 604         if ((iflist[pi->ipi6_ifindex]->ifm_flags & IFF_UP) == 0) {
 605                 syslog(LOG_INFO,
 606                        "<%s> received data on a disabled interface (%s)",
 607                        __FUNCTION__,
 608                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 609                 return;
 610         }
 611
 612 #ifdef OLDRAWSOCKET
 613         if (i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) {
 614                 syslog(LOG_ERR,
 615                        "<%s> packet size(%d) is too short",
 616                        __FUNCTION__, i);
 617                 return;
 618         }
 619
 620         ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base;
 621         icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */
 622 #else
 623         if (i < sizeof(struct icmp6_hdr)) {
 624                 syslog(LOG_ERR,
 625                        "<%s> packet size(%d) is too short",
 626                        __FUNCTION__, i);
 627                 return;
 628         }
 629
 630         icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base;
 631 #endif
 632
 633         switch (icp->icmp6_type) {
 634         case ND_ROUTER_SOLICIT:
 635                 /*
 636                  * Message verification - RFC-2461 6.1.1
 637                  * XXX: these checks must be done in the kernel as well,
 638                  *      but we can't completely rely on them.
 639                  */
 640                 if (*hlimp != 255) {
 641                         syslog(LOG_NOTICE,
 642                             "<%s> RS with invalid hop limit(%d) "
 643                             "received from %s on %s",
 644                             __FUNCTION__, *hlimp,
 645                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 646                             INET6_ADDRSTRLEN),
 647                             if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 648                         return;
 649                 }
 650                 if (icp->icmp6_code) {
 651                         syslog(LOG_NOTICE,
 652                             "<%s> RS with invalid ICMP6 code(%d) "
 653                             "received from %s on %s",
 654                             __FUNCTION__, icp->icmp6_code,
 655                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 656                             INET6_ADDRSTRLEN),
 657                             if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 658                         return;
 659                 }
 660                 if (i < sizeof(struct nd_router_solicit)) {
 661                         syslog(LOG_NOTICE,
 662                             "<%s> RS from %s on %s does not have enough "
 663                             "length (len = %d)",
 664                             __FUNCTION__,
 665                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 666                             INET6_ADDRSTRLEN),
 667                             if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
 668                         return;
 669                 }
 670                 rs_input(i, (struct nd_router_solicit *)icp, pi, &from);
 671                 break;
 672         case ND_ROUTER_ADVERT:
 673                 /*
 674                  * Message verification - RFC-2461 6.1.2
 675                  * XXX: there's a same dilemma as above...
 676                  */
 677                 if (*hlimp != 255) {
 678                         syslog(LOG_NOTICE,
 679                             "<%s> RA with invalid hop limit(%d) "
 680                             "received from %s on %s",
 681                             __FUNCTION__, *hlimp,
 682                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 683                             INET6_ADDRSTRLEN),
 684                             if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 685                         return;
 686                 }
 687                 if (icp->icmp6_code) {
 688                         syslog(LOG_NOTICE,
 689                             "<%s> RA with invalid ICMP6 code(%d) "
 690                             "received from %s on %s",
 691                             __FUNCTION__, icp->icmp6_code,
 692                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 693                             INET6_ADDRSTRLEN),
 694                             if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 695                         return;
 696                 }
 697                 if (i < sizeof(struct nd_router_advert)) {
 698                         syslog(LOG_NOTICE,
 699                             "<%s> RA from %s on %s does not have enough "
 700                             "length (len = %d)",
 701                             __FUNCTION__,
 702                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 703                             INET6_ADDRSTRLEN),
 704                             if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
 705                         return;
 706                 }
 707                 ra_input(i, (struct nd_router_advert *)icp, pi, &from);
 708                 break;
 709         case ICMP6_ROUTER_RENUMBERING:
 710                 if (accept_rr == 0) {
 711                         syslog(LOG_ERR, "<%s> received a router renumbering "
 712                             "message, but not allowed to be accepted",
 713                             __FUNCTION__);
 714                         break;
 715                 }
 716                 rr_input(i, (struct icmp6_router_renum *)icp, pi, &from,
 717                          &dst);
 718                 break;
 719         default:
 720                 /*
 721                  * Note that this case is POSSIBLE, especially just
 722                  * after invocation of the daemon. This is because we
 723                  * could receive message after opening the socket and
 724                  * before setting ICMP6 type filter(see sock_open()).
 725                  */
 726                 syslog(LOG_ERR, "<%s> invalid icmp type(%d)",
 727                     __FUNCTION__, icp->icmp6_type);
 728                 return;
 729         }
 730
 731         return;
 732 }
 733
 734 static void
 735 rs_input(int len, struct nd_router_solicit *rs,
 736          struct in6_pktinfo *pi, struct sockaddr_in6 *from)
 737 {
 738         u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
 739         union nd_opts ndopts;
 740         struct rainfo *ra;
 741
 742         syslog(LOG_DEBUG,
 743                "<%s> RS received from %s on %s",
 744                __FUNCTION__,
 745                inet_ntop(AF_INET6, &from->sin6_addr,
 746                          ntopbuf, INET6_ADDRSTRLEN),
 747                if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 748
 749         /* ND option check */
 750         memset(&ndopts, 0, sizeof(ndopts));
 751         if (nd6_options((struct nd_opt_hdr *)(rs + 1),
 752                         len - sizeof(struct nd_router_solicit),
 753                          &ndopts, NDOPT_FLAG_SRCLINKADDR)) {
 754                 syslog(LOG_DEBUG,
 755                        "<%s> ND option check failed for an RS from %s on %s",
 756                        __FUNCTION__,
 757                        inet_ntop(AF_INET6, &from->sin6_addr,
 758                                  ntopbuf, INET6_ADDRSTRLEN),
 759                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 760                 return;
 761         }
 762
 763         /*
 764          * If the IP source address is the unspecified address, there
 765          * must be no source link-layer address option in the message.
 766          * (RFC-2461 6.1.1)
 767          */
 768         if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) &&
 769             ndopts.nd_opts_src_lladdr) {
 770                 syslog(LOG_ERR,
 771                        "<%s> RS from unspecified src on %s has a link-layer"
 772                        " address option",
 773                        __FUNCTION__,
 774                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 775                 goto done;
 776         }
 777
 778         ra = ralist;
 779         while (ra != NULL) {
 780                 if (pi->ipi6_ifindex == ra->ifindex)
 781                         break;
 782                 ra = ra->next;
 783         }
 784         if (ra == NULL) {
 785                 syslog(LOG_INFO,
 786                        "<%s> RS received on non advertising interface(%s)",
 787                        __FUNCTION__,
 788                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 789                 goto done;
 790         }
 791
 792         ra->rsinput++;          /* increment statistics */
 793
 794         /*
 795          * Decide whether to send RA according to the rate-limit
 796          * consideration.
 797          */
 798         {
 799                 long delay;     /* must not be greater than 1000000 */
 800                 struct timeval interval, now, min_delay, tm_tmp, *rest;
 801                 struct soliciter *sol;
 802
 803                 /*
 804                  * record sockaddr waiting for RA, if possible
 805                  */
 806                 sol = (struct soliciter *)malloc(sizeof(*sol));
 807                 if (sol) {
 808                         sol->addr = *from;
 809                         /*XXX RFC2553 need clarification on flowinfo */
 810                         sol->addr.sin6_flowinfo = 0;
 811                         sol->next = ra->soliciter;
 812                         ra->soliciter = sol->next;
 813                 }
 814
 815                 /*
 816                  * If there is already a waiting RS packet, don't
 817                  * update the timer.
 818                  */
 819                 if (ra->waiting++)
 820                         goto done;
 821
 822                 /*
 823                  * Compute a random delay. If the computed value
 824                  * corresponds to a time later than the time the next
 825                  * multicast RA is scheduled to be sent, ignore the random
 826                  * delay and send the advertisement at the
 827                  * already-scheduled time. RFC-2461 6.2.6
 828                  */
 829                 delay = random() % MAX_RA_DELAY_TIME;
 830                 interval.tv_sec = 0;
 831                 interval.tv_usec = delay;
 832                 rest = rtadvd_timer_rest(ra->timer);
 833                 if (TIMEVAL_LT(*rest, interval)) {
 834                         syslog(LOG_DEBUG,
 835                                "<%s> random delay is larger than "
 836                                "the rest of normal timer",
 837                                __FUNCTION__);
 838                         interval = *rest;
 839                 }
 840
 841                 /*
 842                  * If we sent a multicast Router Advertisement within
 843                  * the last MIN_DELAY_BETWEEN_RAS seconds, schedule
 844                  * the advertisement to be sent at a time corresponding to
 845                  * MIN_DELAY_BETWEEN_RAS plus the random value after the
 846                  * previous advertisement was sent.
 847                  */
 848                 gettimeofday(&now, NULL);
 849                 TIMEVAL_SUB(&now, &ra->lastsent, &tm_tmp);
 850                 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS;
 851                 min_delay.tv_usec = 0;
 852                 if (TIMEVAL_LT(tm_tmp, min_delay)) {
 853                         TIMEVAL_SUB(&min_delay, &tm_tmp, &min_delay);
 854                         TIMEVAL_ADD(&min_delay, &interval, &interval);
 855                 }
 856                 rtadvd_set_timer(&interval, ra->timer);
 857                 goto done;
 858         }
 859
 860   done:
 861         free_ndopts(&ndopts);
 862         return;
 863 }
 864
 865 static void
 866 ra_input(int len, struct nd_router_advert *ra,
 867          struct in6_pktinfo *pi, struct sockaddr_in6 *from)
 868 {
 869         struct rainfo *rai;
 870         u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
 871         union nd_opts ndopts;
 872         char *on_off[] = {"OFF", "ON"};
 873         u_int32_t reachabletime, retranstimer, mtu;
 874         int inconsistent = 0;
 875
 876         syslog(LOG_DEBUG,
 877                "<%s> RA received from %s on %s",
 878                __FUNCTION__,
 879                inet_ntop(AF_INET6, &from->sin6_addr,
 880                          ntopbuf, INET6_ADDRSTRLEN),
 881                if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 882
 883         /* ND option check */
 884         memset(&ndopts, 0, sizeof(ndopts));
 885         if (nd6_options((struct nd_opt_hdr *)(ra + 1),
 886                         len - sizeof(struct nd_router_advert),
 887                         &ndopts, NDOPT_FLAG_SRCLINKADDR |
 888                         NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU)) {
 889                 syslog(LOG_ERR,
 890                        "<%s> ND option check failed for an RA from %s on %s",
 891                        __FUNCTION__,
 892                        inet_ntop(AF_INET6, &from->sin6_addr,
 893                                  ntopbuf, INET6_ADDRSTRLEN),
 894                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 895                 return;
 896         }
 897
 898         /*
 899          * RA consistency check according to RFC-2461 6.2.7
 900          */
 901         if ((rai = if_indextorainfo(pi->ipi6_ifindex)) == 0) {
 902                 syslog(LOG_INFO,
 903                        "<%s> received RA from %s on non-advertising"
 904                        " interface(%s)",
 905                        __FUNCTION__,
 906                        inet_ntop(AF_INET6, &from->sin6_addr,
 907                                  ntopbuf, INET6_ADDRSTRLEN),
 908                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 909                 goto done;
 910         }
 911         rai->rainput++;         /* increment statistics */
 912
 913         /* Cur Hop Limit value */
 914         if (ra->nd_ra_curhoplimit && rai->hoplimit &&
 915             ra->nd_ra_curhoplimit != rai->hoplimit) {
 916                 syslog(LOG_INFO,
 917                        "<%s> CurHopLimit inconsistent on %s:"
 918                        " %d from %s, %d from us",
 919                        __FUNCTION__,
 920                        rai->ifname,
 921                        ra->nd_ra_curhoplimit,
 922                        inet_ntop(AF_INET6, &from->sin6_addr,
 923                                  ntopbuf, INET6_ADDRSTRLEN),
 924                        rai->hoplimit);
 925                 inconsistent++;
 926         }
 927         /* M flag */
 928         if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) !=
 929             rai->managedflg) {
 930                 syslog(LOG_INFO,
 931                        "<%s> M flag inconsistent on %s:"
 932                        " %s from %s, %s from us",
 933                        __FUNCTION__,
 934                        rai->ifname,
 935                        on_off[!rai->managedflg],
 936                        inet_ntop(AF_INET6, &from->sin6_addr,
 937                                  ntopbuf, INET6_ADDRSTRLEN),
 938                        on_off[rai->managedflg]);
 939                 inconsistent++;
 940         }
 941         /* O flag */
 942         if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) !=
 943             rai->otherflg) {
 944                 syslog(LOG_INFO,
 945                        "<%s> O flag inconsistent on %s:"
 946                        " %s from %s, %s from us",
 947                        __FUNCTION__,
 948                        rai->ifname,
 949                        on_off[!rai->otherflg],
 950                        inet_ntop(AF_INET6, &from->sin6_addr,
 951                                  ntopbuf, INET6_ADDRSTRLEN),
 952                        on_off[rai->otherflg]);
 953                 inconsistent++;
 954         }
 955         /* Reachable Time */
 956         reachabletime = ntohl(ra->nd_ra_reachable);
 957         if (reachabletime && rai->reachabletime &&
 958             reachabletime != rai->reachabletime) {
 959                 syslog(LOG_INFO,
 960                        "<%s> ReachableTime inconsistent on %s:"
 961                        " %d from %s, %d from us",
 962                        __FUNCTION__,
 963                        rai->ifname,
 964                        reachabletime,
 965                        inet_ntop(AF_INET6, &from->sin6_addr,
 966                                  ntopbuf, INET6_ADDRSTRLEN),
 967                        rai->reachabletime);
 968                 inconsistent++;
 969         }
 970         /* Retrans Timer */
 971         retranstimer = ntohl(ra->nd_ra_retransmit);
 972         if (retranstimer && rai->retranstimer &&
 973             retranstimer != rai->retranstimer) {
 974                 syslog(LOG_INFO,
 975                        "<%s> RetranceTimer inconsistent on %s:"
 976                        " %d from %s, %d from us",
 977                        __FUNCTION__,
 978                        rai->ifname,
 979                        retranstimer,
 980                        inet_ntop(AF_INET6, &from->sin6_addr,
 981                                  ntopbuf, INET6_ADDRSTRLEN),
 982                        rai->retranstimer);
 983                 inconsistent++;
 984         }
 985         /* Values in the MTU options */
 986         if (ndopts.nd_opts_mtu) {
 987                 mtu = ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu);
 988                 if (mtu && rai->linkmtu && mtu != rai->linkmtu) {
 989                         syslog(LOG_INFO,
 990                                "<%s> MTU option value inconsistent on %s:"
 991                                " %d from %s, %d from us",
 992                                __FUNCTION__,
 993                                rai->ifname, mtu,
 994                                inet_ntop(AF_INET6, &from->sin6_addr,
 995                                          ntopbuf, INET6_ADDRSTRLEN),
 996                                rai->linkmtu);
 997                         inconsistent++;
 998                 }
 999         }
1000         /* Preferred and Valid Lifetimes for prefixes */
1001         {
1002                 struct nd_optlist *optp = ndopts.nd_opts_list;
1003
1004                 if (ndopts.nd_opts_pi) {
1005                         if (prefix_check(ndopts.nd_opts_pi, rai, from))
1006                                 inconsistent++;
1007                 }
1008                 while (optp) {
1009                         if (prefix_check((struct nd_opt_prefix_info *)optp->opt,
1010                                          rai, from))
1011                                 inconsistent++;
1012                         optp = optp->next;
1013                 }
1014         }
1015
1016         if (inconsistent)
1017                 rai->rainconsistent++;
1018
1019   done:
1020         free_ndopts(&ndopts);
1021         return;
1022 }
1023
1024 /* return a non-zero value if the received prefix is inconsitent with ours */
1025 static int
1026 prefix_check(struct nd_opt_prefix_info *pinfo,
1027              struct rainfo *rai, struct sockaddr_in6 *from)
1028 {
1029         u_int32_t preferred_time, valid_time;
1030         struct prefix *pp;
1031         int inconsistent = 0;
1032         u_char ntopbuf[INET6_ADDRSTRLEN], prefixbuf[INET6_ADDRSTRLEN];
1033         struct timeval now;
1034
1035 #if 0                           /* impossible */
1036         if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION)
1037                 return(0);
1038 #endif
1039
1040         /*
1041          * log if the adveritsed prefix has link-local scope(sanity check?)
1042          */
1043         if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) {
1044                 syslog(LOG_INFO,
1045                        "<%s> link-local prefix %s/%d is advertised "
1046                        "from %s on %s",
1047                        __FUNCTION__,
1048                        inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1049                                  prefixbuf, INET6_ADDRSTRLEN),
1050                        pinfo->nd_opt_pi_prefix_len,
1051                        inet_ntop(AF_INET6, &from->sin6_addr,
1052                                  ntopbuf, INET6_ADDRSTRLEN),
1053                        rai->ifname);
1054         }
1055
1056         if ((pp = find_prefix(rai, &pinfo->nd_opt_pi_prefix,
1057                               pinfo->nd_opt_pi_prefix_len)) == NULL) {
1058                 syslog(LOG_INFO,
1059                        "<%s> prefix %s/%d from %s on %s is not in our list",
1060                        __FUNCTION__,
1061                        inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1062                                  prefixbuf, INET6_ADDRSTRLEN),
1063                        pinfo->nd_opt_pi_prefix_len,
1064                        inet_ntop(AF_INET6, &from->sin6_addr,
1065                                  ntopbuf, INET6_ADDRSTRLEN),
1066                        rai->ifname);
1067                 return(0);
1068         }
1069
1070         preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time);
1071         if (pp->pltimeexpire) {
1072                 /*
1073                  * The lifetime is decremented in real time, so we should
1074                  * compare the expiration time.
1075                  * (RFC 2461 Section 6.2.7.)
1076                  * XXX: can we really expect that all routers on the link
1077                  * have synchronized clocks?
1078                  */
1079                 gettimeofday(&now, NULL);
1080                 preferred_time += now.tv_sec;
1081
1082                 if (rai->clockskew &&
1083                     abs(preferred_time - pp->pltimeexpire) > rai->clockskew) {
1084                         syslog(LOG_INFO,
1085                                "<%s> prefeerred lifetime for %s/%d"
1086                                " (decr. in real time) inconsistent on %s:"
1087                                " %d from %s, %ld from us",
1088                                __FUNCTION__,
1089                                inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1090                                          prefixbuf, INET6_ADDRSTRLEN),
1091                                pinfo->nd_opt_pi_prefix_len,
1092                                rai->ifname, preferred_time,
1093                                inet_ntop(AF_INET6, &from->sin6_addr,
1094                                          ntopbuf, INET6_ADDRSTRLEN),
1095                                pp->pltimeexpire);
1096                         inconsistent++;
1097                 }
1098         } else if (preferred_time != pp->preflifetime) {
1099                 syslog(LOG_INFO,
1100                        "<%s> prefeerred lifetime for %s/%d"
1101                        " inconsistent on %s:"
1102                        " %d from %s, %d from us",
1103                        __FUNCTION__,
1104                        inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1105                                  prefixbuf, INET6_ADDRSTRLEN),
1106                        pinfo->nd_opt_pi_prefix_len,
1107                        rai->ifname, preferred_time,
1108                        inet_ntop(AF_INET6, &from->sin6_addr,
1109                                  ntopbuf, INET6_ADDRSTRLEN),
1110                        pp->preflifetime);
1111         }
1112
1113         valid_time = ntohl(pinfo->nd_opt_pi_valid_time);
1114         if (pp->vltimeexpire) {
1115                 gettimeofday(&now, NULL);
1116                 valid_time += now.tv_sec;
1117
1118                 if (rai->clockskew &&
1119                     abs(valid_time - pp->vltimeexpire) > rai->clockskew) {
1120                         syslog(LOG_INFO,
1121                                "<%s> valid lifetime for %s/%d"
1122                                " (decr. in real time) inconsistent on %s:"
1123                                " %d from %s, %ld from us",
1124                                __FUNCTION__,
1125                                inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1126                                          prefixbuf, INET6_ADDRSTRLEN),
1127                                pinfo->nd_opt_pi_prefix_len,
1128                                rai->ifname, preferred_time,
1129                                inet_ntop(AF_INET6, &from->sin6_addr,
1130                                          ntopbuf, INET6_ADDRSTRLEN),
1131                                pp->vltimeexpire);
1132                         inconsistent++;
1133                 }
1134         } else if (valid_time != pp->validlifetime) {
1135                 syslog(LOG_INFO,
1136                        "<%s> valid lifetime for %s/%d"
1137                        " inconsistent on %s:"
1138                        " %d from %s, %d from us",
1139                        __FUNCTION__,
1140                        inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1141                                  prefixbuf, INET6_ADDRSTRLEN),
1142                        pinfo->nd_opt_pi_prefix_len,
1143                        rai->ifname, valid_time,
1144                        inet_ntop(AF_INET6, &from->sin6_addr,
1145                                  ntopbuf, INET6_ADDRSTRLEN),
1146                        pp->validlifetime);
1147                 inconsistent++;
1148         }
1149
1150         return(inconsistent);
1151 }
1152
1153 struct prefix *
1154 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen)
1155 {
1156         struct prefix *pp;
1157         int bytelen, bitlen;
1158
1159         for (pp = rai->prefix.next; pp != &rai->prefix; pp = pp->next) {
1160                 if (plen != pp->prefixlen)
1161                         continue;
1162                 bytelen = plen / 8;
1163                 bitlen = plen % 8;
1164                 if (memcmp((void *)prefix, (void *)&pp->prefix, bytelen))
1165                         continue;
1166                 if (prefix->s6_addr[bytelen] >> (8 - bitlen) ==
1167                     pp->prefix.s6_addr[bytelen] >> (8 - bitlen))
1168                         return(pp);
1169         }
1170
1171         return(NULL);
1172 }
1173
1174 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */
1175 int
1176 prefix_match(struct in6_addr *p0, int plen0,
1177              struct in6_addr *p1, int plen1)
1178 {
1179         int bytelen, bitlen;
1180
1181         if (plen0 < plen1)
1182                 return(0);
1183         bytelen = plen1 / 8;
1184         bitlen = plen1 % 8;
1185         if (memcmp((void *)p0, (void *)p1, bytelen))
1186                 return(0);
1187         if (p0->s6_addr[bytelen] >> (8 - bitlen) ==
1188             p1->s6_addr[bytelen] >> (8 - bitlen))
1189                 return(1);
1190
1191         return(0);
1192 }
1193
1194 static int
1195 nd6_options(struct nd_opt_hdr *hdr, int limit,
1196             union nd_opts *ndopts, u_int32_t optflags)
1197 {
1198         int optlen = 0;
1199
1200         for (; limit > 0; limit -= optlen) {
1201                 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen);
1202                 optlen = hdr->nd_opt_len << 3;
1203                 if (hdr->nd_opt_len == 0) {
1204                         syslog(LOG_ERR,
1205                             "<%s> bad ND option length(0) (type = %d)",
1206                             __FUNCTION__, hdr->nd_opt_type);
1207                         goto bad;
1208                 }
1209
1210                 if (hdr->nd_opt_type > ND_OPT_MTU) {
1211                         syslog(LOG_INFO,
1212                             "<%s> unknown ND option(type %d)",
1213                             __FUNCTION__, hdr->nd_opt_type);
1214                         continue;
1215                 }
1216
1217                 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) {
1218                         syslog(LOG_INFO,
1219                             "<%s> unexpected ND option(type %d)",
1220                                __FUNCTION__, hdr->nd_opt_type);
1221                         continue;
1222                 }
1223
1224                 switch (hdr->nd_opt_type) {
1225                 case ND_OPT_SOURCE_LINKADDR:
1226                 case ND_OPT_TARGET_LINKADDR:
1227                 case ND_OPT_REDIRECTED_HEADER:
1228                 case ND_OPT_MTU:
1229                         if (ndopts->nd_opt_array[hdr->nd_opt_type]) {
1230                                 syslog(LOG_INFO,
1231                                     "<%s> duplicated ND option (type = %d)",
1232                                     __FUNCTION__, hdr->nd_opt_type);
1233                         }
1234                         ndopts->nd_opt_array[hdr->nd_opt_type] = hdr;
1235                         break;
1236                 case ND_OPT_PREFIX_INFORMATION:
1237                 {
1238                         struct nd_optlist *pfxlist;
1239
1240                         if (ndopts->nd_opts_pi == 0) {
1241                                 ndopts->nd_opts_pi =
1242                                     (struct nd_opt_prefix_info *)hdr;
1243                                 continue;
1244                         }
1245                         if ((pfxlist = malloc(sizeof(*pfxlist))) == NULL) {
1246                                 syslog(LOG_ERR, "<%s> can't allocate memory",
1247                                     __FUNCTION__);
1248                                 goto bad;
1249                         }
1250                         pfxlist->next = ndopts->nd_opts_list;
1251                         pfxlist->opt = hdr;
1252                         ndopts->nd_opts_list = pfxlist;
1253
1254                         break;
1255                 }
1256                 default:        /* impossible */
1257                         break;
1258                 }
1259         }
1260
1261         return(0);
1262
1263   bad:
1264         free_ndopts(ndopts);
1265
1266         return(-1);
1267 }
1268
1269 static void
1270 free_ndopts(union nd_opts *ndopts)
1271 {
1272         struct nd_optlist *opt = ndopts->nd_opts_list, *next;
1273
1274         while (opt) {
1275                 next = opt->next;
1276                 free(opt);
1277                 opt = next;
1278         }
1279 }
1280
1281 void
1282 sock_open()
1283 {
1284         struct icmp6_filter filt;
1285         struct ipv6_mreq mreq;
1286         struct rainfo *ra = ralist;
1287         int on;
1288         /* XXX: should be max MTU attached to the node */
1289         static u_char answer[1500];
1290
1291         rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1292                                 CMSG_SPACE(sizeof(int));
1293         rcvcmsgbuf = (u_char *)malloc(rcvcmsgbuflen);
1294         if (rcvcmsgbuf == NULL) {
1295                 syslog(LOG_ERR, "<%s> not enough core", __FUNCTION__);
1296                 exit(1);
1297         }
1298
1299         sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1300                                 CMSG_SPACE(sizeof(int));
1301         sndcmsgbuf = (u_char *)malloc(sndcmsgbuflen);
1302         if (sndcmsgbuf == NULL) {
1303                 syslog(LOG_ERR, "<%s> not enough core", __FUNCTION__);
1304                 exit(1);
1305         }
1306
1307         if ((sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
1308                 syslog(LOG_ERR, "<%s> socket: %s", __FUNCTION__,
1309                        strerror(errno));
1310                 exit(1);
1311         }
1312
1313         /* specify to tell receiving interface */
1314         on = 1;
1315 #ifdef IPV6_RECVPKTINFO
1316         if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
1317                        sizeof(on)) < 0) {
1318                 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s",
1319                        __FUNCTION__, strerror(errno));
1320                 exit(1);
1321         }
1322 #else  /* old adv. API */
1323         if (setsockopt(sock, IPPROTO_IPV6, IPV6_PKTINFO, &on,
1324                        sizeof(on)) < 0) {
1325                 syslog(LOG_ERR, "<%s> IPV6_PKTINFO: %s",
1326                        __FUNCTION__, strerror(errno));
1327                 exit(1);
1328         }
1329 #endif
1330
1331         on = 1;
1332         /* specify to tell value of hoplimit field of received IP6 hdr */
1333 #ifdef IPV6_RECVHOPLIMIT
1334         if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
1335                        sizeof(on)) < 0) {
1336                 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s",
1337                        __FUNCTION__, strerror(errno));
1338                 exit(1);
1339         }
1340 #else  /* old adv. API */
1341         if (setsockopt(sock, IPPROTO_IPV6, IPV6_HOPLIMIT, &on,
1342                        sizeof(on)) < 0) {
1343                 syslog(LOG_ERR, "<%s> IPV6_HOPLIMIT: %s",
1344                        __FUNCTION__, strerror(errno));
1345                 exit(1);
1346         }
1347 #endif
1348
1349         ICMP6_FILTER_SETBLOCKALL(&filt);
1350         ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt);
1351         ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
1352         if (accept_rr)
1353                 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt);
1354         if (setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
1355                        sizeof(filt)) < 0) {
1356                 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s",
1357                        __FUNCTION__, strerror(errno));
1358                 exit(1);
1359         }
1360
1361         /*
1362          * join all routers multicast address on each advertising interface.
1363          */
1364         if (inet_pton(AF_INET6, ALLROUTERS_LINK,
1365                       &mreq.ipv6mr_multiaddr.s6_addr)
1366             != 1) {
1367                 syslog(LOG_ERR, "<%s> inet_pton failed(library bug?)",
1368                        __FUNCTION__);
1369                 exit(1);
1370         }
1371         while (ra) {
1372                 mreq.ipv6mr_interface = ra->ifindex;
1373                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq,
1374                                sizeof(mreq)) < 0) {
1375                         syslog(LOG_ERR, "<%s> IPV6_JOIN_GROUP(link) on %s: %s",
1376                                __FUNCTION__, ra->ifname, strerror(errno));
1377                         exit(1);
1378                 }
1379                 ra = ra->next;
1380         }
1381
1382         /*
1383          * When attending router renumbering, join all-routers site-local
1384          * multicast group.
1385          */
1386         if (accept_rr) {
1387                 if (inet_pton(AF_INET6, ALLROUTERS_SITE,
1388                               &in6a_site_allrouters) != 1) {
1389                         syslog(LOG_ERR, "<%s> inet_pton failed(library bug?)",
1390                                __FUNCTION__);
1391                         exit(1);
1392                 }
1393                 mreq.ipv6mr_multiaddr = in6a_site_allrouters;
1394                 if (mcastif) {
1395                         if ((mreq.ipv6mr_interface = if_nametoindex(mcastif))
1396                             == 0) {
1397                                 syslog(LOG_ERR,
1398                                        "<%s> invalid interface: %s",
1399                                        __FUNCTION__, mcastif);
1400                                 exit(1);
1401                         }
1402                 } else
1403                         mreq.ipv6mr_interface = ralist->ifindex;
1404                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP,
1405                                &mreq, sizeof(mreq)) < 0) {
1406                         syslog(LOG_ERR,
1407                                "<%s> IPV6_JOIN_GROUP(site) on %s: %s",
1408                                __FUNCTION__,
1409                                mcastif ? mcastif : ralist->ifname,
1410                                strerror(errno));
1411                         exit(1);
1412                 }
1413         }
1414
1415         /* initialize msghdr for receiving packets */
1416         rcviov[0].iov_base = (caddr_t)answer;
1417         rcviov[0].iov_len = sizeof(answer);
1418         rcvmhdr.msg_name = (caddr_t)&from;
1419         rcvmhdr.msg_namelen = sizeof(from);
1420         rcvmhdr.msg_iov = rcviov;
1421         rcvmhdr.msg_iovlen = 1;
1422         rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
1423         rcvmhdr.msg_controllen = rcvcmsgbuflen;
1424
1425         /* initialize msghdr for sending packets */
1426         sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
1427         sndmhdr.msg_iov = sndiov;
1428         sndmhdr.msg_iovlen = 1;
1429         sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
1430         sndmhdr.msg_controllen = sndcmsgbuflen;
1431
1432         return;
1433 }
1434
1435 /* open a routing socket to watch the routing table */
1436 static void
1437 rtsock_open()
1438 {
1439         if ((rtsock = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) {
1440                 syslog(LOG_ERR,
1441                        "<%s> socket: %s", __FUNCTION__, strerror(errno));
1442                 exit(1);
1443         }
1444 }
1445
1446 struct rainfo *
1447 if_indextorainfo(int index)
1448 {
1449         struct rainfo *rai = ralist;
1450
1451         for (rai = ralist; rai; rai = rai->next) {
1452                 if (rai->ifindex == index)
1453                         return(rai);
1454         }
1455
1456         return(NULL);           /* search failed */
1457 }
1458
1459 static void
1460 ra_output(rainfo)
1461 struct rainfo *rainfo;
1462 {
1463         int i;
1464         struct cmsghdr *cm;
1465         struct in6_pktinfo *pi;
1466         struct soliciter *sol, *nextsol;
1467
1468         if ((iflist[rainfo->ifindex]->ifm_flags & IFF_UP) == 0) {
1469                 syslog(LOG_DEBUG, "<%s> %s is not up, skip sending RA",
1470                        __FUNCTION__, rainfo->ifname);
1471                 return;
1472         }
1473
1474         make_packet(rainfo);    /* XXX: inefficient */
1475
1476         sndmhdr.msg_name = (caddr_t)&sin6_allnodes;
1477         sndmhdr.msg_iov[0].iov_base = (caddr_t)rainfo->ra_data;
1478         sndmhdr.msg_iov[0].iov_len = rainfo->ra_datalen;
1479
1480         cm = CMSG_FIRSTHDR(&sndmhdr);
1481         /* specify the outgoing interface */
1482         cm->cmsg_level = IPPROTO_IPV6;
1483         cm->cmsg_type = IPV6_PKTINFO;
1484         cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
1485         pi = (struct in6_pktinfo *)CMSG_DATA(cm);
1486         memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr));       /*XXX*/
1487         pi->ipi6_ifindex = rainfo->ifindex;
1488
1489         /* specify the hop limit of the packet */
1490         {
1491                 int hoplimit = 255;
1492
1493                 cm = CMSG_NXTHDR(&sndmhdr, cm);
1494                 cm->cmsg_level = IPPROTO_IPV6;
1495                 cm->cmsg_type = IPV6_HOPLIMIT;
1496                 cm->cmsg_len = CMSG_LEN(sizeof(int));
1497                 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
1498         }
1499
1500         syslog(LOG_DEBUG,
1501                "<%s> send RA on %s, # of waitings = %d",
1502                __FUNCTION__, rainfo->ifname, rainfo->waiting);
1503
1504         i = sendmsg(sock, &sndmhdr, 0);
1505
1506         if (i < 0 || i != rainfo->ra_datalen)  {
1507                 if (i < 0) {
1508                         syslog(LOG_ERR, "<%s> sendmsg on %s: %s",
1509                                __FUNCTION__, rainfo->ifname,
1510                                strerror(errno));
1511                 }
1512         }
1513
1514         /*
1515          * unicast advertisements
1516          * XXX commented out.  reason: though spec does not forbit it, unicast
1517          * advert does not really help
1518          */
1519         for (sol = rainfo->soliciter; sol; sol = nextsol) {
1520                 nextsol = sol->next;
1521
1522 #if 0
1523                 sndmhdr.msg_name = (caddr_t)&sol->addr;
1524                 i = sendmsg(sock, &sndmhdr, 0);
1525                 if (i < 0 || i != rainfo->ra_datalen)  {
1526                         if (i < 0) {
1527                                 syslog(LOG_ERR,
1528                                     "<%s> unicast sendmsg on %s: %s",
1529                                     __FUNCTION__, rainfo->ifname,
1530                                     strerror(errno));
1531                         }
1532                 }
1533 #endif
1534
1535                 sol->next = NULL;
1536                 free(sol);
1537         }
1538         rainfo->soliciter = NULL;
1539
1540         /* update counter */
1541         if (rainfo->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS)
1542                 rainfo->initcounter++;
1543         rainfo->raoutput++;
1544
1545         /* update timestamp */
1546         gettimeofday(&rainfo->lastsent, NULL);
1547
1548         /* reset waiting conter */
1549         rainfo->waiting = 0;
1550 }
1551
1552 /* process RA timer */
1553 void
1554 ra_timeout(void *data)
1555 {
1556         struct rainfo *rai = (struct rainfo *)data;
1557
1558 #ifdef notyet
1559         /* if necessary, reconstruct the packet. */
1560 #endif
1561
1562         syslog(LOG_DEBUG,
1563                "<%s> RA timer on %s is expired",
1564                __FUNCTION__, rai->ifname);
1565
1566         ra_output(rai);
1567 }
1568
1569 /* update RA timer */
1570 void
1571 ra_timer_update(void *data, struct timeval *tm)
1572 {
1573         struct rainfo *rai = (struct rainfo *)data;
1574         long interval;
1575
1576         /*
1577          * Whenever a multicast advertisement is sent from an interface,
1578          * the timer is reset to a uniformly-distributed random value
1579          * between the interface's configured MinRtrAdvInterval and
1580          * MaxRtrAdvInterval (RFC2461 6.2.4).
1581          */
1582         interval = rai->mininterval;
1583         interval += random() % (rai->maxinterval - rai->mininterval);
1584
1585         /*
1586          * For the first few advertisements (up to
1587          * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen interval
1588          * is greater than MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer
1589          * SHOULD be set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead.
1590          * (RFC-2461 6.2.4)
1591          */
1592         if (rai->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS &&
1593             interval > MAX_INITIAL_RTR_ADVERT_INTERVAL)
1594                 interval = MAX_INITIAL_RTR_ADVERT_INTERVAL;
1595
1596         tm->tv_sec = interval;
1597         tm->tv_usec = 0;
1598
1599         syslog(LOG_DEBUG,
1600                "<%s> RA timer on %s is set to %ld:%ld",
1601                __FUNCTION__, rai->ifname,
1602                (long int)tm->tv_sec, (long int)tm->tv_usec);
1603
1604         return;
1605 }