usr.sbin/rtadvd/rtadvd.c

   1 /*      $KAME: rtadvd.c,v 1.50 2001/02/04 06:15:15 itojun Exp $ */
   2
   3 /*
   4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the project nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  * $FreeBSD: src/usr.sbin/rtadvd/rtadvd.c,v 1.3.2.4 2003/04/05 10:31:58 ume Exp $
  32  * $DragonFly: src/usr.sbin/rtadvd/rtadvd.c,v 1.3 2003/11/03 19:31:42 eirikn Exp $
  33  */
  34
  35 #include <sys/param.h>
  36 #include <sys/socket.h>
  37 #include <sys/uio.h>
  38 #include <sys/time.h>
  39 #include <sys/queue.h>
  40
  41 #include <net/if.h>
  42 #include <net/route.h>
  43 #include <net/if_dl.h>
  44 #include <netinet/in.h>
  45 #include <netinet/ip6.h>
  46 #include <netinet6/ip6_var.h>
  47 #include <netinet/icmp6.h>
  48
  49 #include <arpa/inet.h>
  50
  51 #include <time.h>
  52 #include <unistd.h>
  53 #include <stdio.h>
  54 #include <stdlib.h>
  55 #include <err.h>
  56 #include <errno.h>
  57 #include <string.h>
  58 #include <stdlib.h>
  59 #include <syslog.h>
  60 #include "rtadvd.h"
  61 #include "rrenum.h"
  62 #include "advcap.h"
  63 #include "timer.h"
  64 #include "if.h"
  65 #include "config.h"
  66 #include "dump.h"
  67
  68 struct msghdr rcvmhdr;
  69 static u_char *rcvcmsgbuf;
  70 static size_t rcvcmsgbuflen;
  71 static u_char *sndcmsgbuf = NULL;
  72 static size_t sndcmsgbuflen;
  73 static int do_dump;
  74 static int do_die;
  75 struct msghdr sndmhdr;
  76 struct iovec rcviov[2];
  77 struct iovec sndiov[2];
  78 struct sockaddr_in6 from;
  79 struct sockaddr_in6 sin6_allnodes = {sizeof(sin6_allnodes), AF_INET6};
  80 struct in6_addr in6a_site_allrouters;
  81 static char *dumpfilename = "/var/run/rtadvd.dump"; /* XXX: should be configurable */
  82 static char *pidfilename = "/var/run/rtadvd.pid"; /* should be configurable */
  83 static char *mcastif;
  84 int sock;
  85 int rtsock = -1;
  86 #ifdef MIP6
  87 int mobileip6 = 0;
  88 #endif
  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[7];
 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(void);
 147
 148 int
 149 main(argc, argv)
 150         int argc;
 151         char *argv[];
 152 {
 153         fd_set fdset;
 154         int maxfd = 0;
 155         struct timeval *timeout;
 156         int i, ch;
 157         int fflag = 0;
 158         FILE *pidfp;
 159         pid_t pid;
 160
 161         openlog("rtadvd", LOG_NDELAY|LOG_PID, LOG_DAEMON);
 162
 163         /* get command line options and arguments */
 164 #ifdef MIP6
 165 #define OPTIONS "c:dDfM:mRs"
 166 #else
 167 #define OPTIONS "c:dDfM:Rs"
 168 #endif
 169         while ((ch = getopt(argc, argv, OPTIONS)) != -1) {
 170 #undef OPTIONS
 171                 switch (ch) {
 172                 case 'c':
 173                         conffile = optarg;
 174                         break;
 175                 case 'd':
 176                         dflag = 1;
 177                         break;
 178                 case 'D':
 179                         dflag = 2;
 180                         break;
 181                 case 'f':
 182                         fflag = 1;
 183                         break;
 184                 case 'M':
 185                         mcastif = optarg;
 186                         break;
 187 #ifdef MIP6
 188                 case 'm':
 189                         mobileip6 = 1;
 190                         break;
 191 #endif
 192                 case 'R':
 193                         fprintf(stderr, "rtadvd: "
 194                                 "the -R option is currently ignored.\n");
 195                         /* accept_rr = 1; */
 196                         /* run anyway... */
 197                         break;
 198                 case 's':
 199                         sflag = 1;
 200                         break;
 201                 }
 202         }
 203         argc -= optind;
 204         argv += optind;
 205         if (argc == 0) {
 206                 fprintf(stderr,
 207 #ifdef MIP6
 208                         "usage: rtadvd [-dDfMmRs] [-c conffile] "
 209 #else
 210                         "usage: rtadvd [-dDfMRs] [-c conffile] "
 211 #endif
 212                         "interfaces...\n");
 213                 exit(1);
 214         }
 215
 216         /* set log level */
 217         if (dflag == 0)
 218                 (void)setlogmask(LOG_UPTO(LOG_ERR));
 219         if (dflag == 1)
 220                 (void)setlogmask(LOG_UPTO(LOG_INFO));
 221
 222         /* timer initialization */
 223         rtadvd_timer_init();
 224
 225         /* random value initialization */
 226         srandom((u_long)time(NULL));
 227
 228         /* get iflist block from kernel */
 229         init_iflist();
 230
 231         while (argc--)
 232                 getconfig(*argv++);
 233
 234         if (inet_pton(AF_INET6, ALLNODES, &sin6_allnodes.sin6_addr) != 1) {
 235                 fprintf(stderr, "fatal: inet_pton failed\n");
 236                 exit(1);
 237         }
 238         sock_open();
 239
 240         if (!fflag)
 241                 daemon(1, 0);
 242
 243         /* record the current PID */
 244         pid = getpid();
 245         if ((pidfp = fopen(pidfilename, "w")) == NULL) {
 246                 syslog(LOG_ERR,
 247                     "<%s> failed to open a log file(%s), run anyway.",
 248                     __FUNCTION__, pidfilename);
 249         } else {
 250                 fprintf(pidfp, "%d\n", pid);
 251                 fclose(pidfp);
 252         }
 253
 254         FD_ZERO(&fdset);
 255         FD_SET(sock, &fdset);
 256         maxfd = sock;
 257         if (sflag == 0) {
 258                 rtsock_open();
 259                 FD_SET(rtsock, &fdset);
 260                 if (rtsock > sock)
 261                         maxfd = rtsock;
 262         } else
 263                 rtsock = -1;
 264
 265         signal(SIGTERM, (void *)set_die);
 266         signal(SIGUSR1, (void *)rtadvd_set_dump_file);
 267
 268         while (1) {
 269                 struct fd_set select_fd = fdset; /* reinitialize */
 270
 271                 if (do_dump) {  /* SIGUSR1 */
 272                         do_dump = 0;
 273                         rtadvd_dump_file(dumpfilename);
 274                 }
 275
 276                 if (do_die) {
 277                         die();
 278                         /*NOTREACHED*/
 279                 }
 280
 281                 /* timer expiration check and reset the timer */
 282                 timeout = rtadvd_check_timer();
 283
 284                 if (timeout != NULL) {
 285                         syslog(LOG_DEBUG,
 286                             "<%s> set timer to %ld:%ld. waiting for "
 287                             "inputs or timeout", __FUNCTION__,
 288                             (long int)timeout->tv_sec,
 289                             (long int)timeout->tv_usec);
 290                 } else {
 291                         syslog(LOG_DEBUG,
 292                             "<%s> there's no timer. waiting for inputs",
 293                             __FUNCTION__);
 294                 }
 295
 296                 if ((i = select(maxfd + 1, &select_fd,
 297                                 NULL, NULL, timeout)) < 0) {
 298                         /* EINTR would occur upon SIGUSR1 for status dump */
 299                         if (errno != EINTR)
 300                                 syslog(LOG_ERR, "<%s> select: %s",
 301                                     __FUNCTION__, strerror(errno));
 302                         continue;
 303                 }
 304                 if (i == 0)     /* timeout */
 305                         continue;
 306                 if (rtsock != -1 && FD_ISSET(rtsock, &select_fd))
 307                         rtmsg_input();
 308                 if (FD_ISSET(sock, &select_fd))
 309                         rtadvd_input();
 310         }
 311         exit(0);                /* NOTREACHED */
 312 }
 313
 314 static void
 315 rtadvd_set_dump_file()
 316 {
 317         do_dump = 1;
 318 }
 319
 320 static void
 321 set_die(sig)
 322         int sig;
 323 {
 324         do_die = 1;
 325 }
 326
 327 static void
 328 die()
 329 {
 330         struct rainfo *ra;
 331         int i;
 332         const int retrans = MAX_FINAL_RTR_ADVERTISEMENTS;
 333
 334         if (dflag > 1) {
 335                 syslog(LOG_DEBUG, "<%s> cease to be an advertising router\n",
 336                     __FUNCTION__);
 337         }
 338
 339         for (ra = ralist; ra; ra = ra->next) {
 340                 ra->lifetime = 0;
 341                 make_packet(ra);
 342         }
 343         for (i = 0; i < retrans; i++) {
 344                 for (ra = ralist; ra; ra = ra->next)
 345                         ra_output(ra);
 346                 sleep(MIN_DELAY_BETWEEN_RAS);
 347         }
 348         exit(0);
 349         /*NOTREACHED*/
 350 }
 351
 352 static void
 353 rtmsg_input()
 354 {
 355         int n, type, ifindex = 0, plen;
 356         size_t len;
 357         char msg[2048], *next, *lim;
 358         u_char ifname[IF_NAMESIZE];
 359         struct prefix *prefix;
 360         struct rainfo *rai;
 361         struct in6_addr *addr;
 362         char addrbuf[INET6_ADDRSTRLEN];
 363
 364         n = read(rtsock, msg, sizeof(msg));
 365         if (dflag > 1) {
 366                 syslog(LOG_DEBUG, "<%s> received a routing message "
 367                     "(type = %d, len = %d)", __FUNCTION__, rtmsg_type(msg), n);
 368         }
 369         if (n > rtmsg_len(msg)) {
 370                 /*
 371                  * This usually won't happen for messages received on
 372                  * a routing socket.
 373                  */
 374                 if (dflag > 1)
 375                         syslog(LOG_DEBUG,
 376                             "<%s> received data length is larger than "
 377                             "1st routing message len. multiple messages? "
 378                             "read %d bytes, but 1st msg len = %d",
 379                             __FUNCTION__, n, rtmsg_len(msg));
 380 #if 0
 381                 /* adjust length */
 382                 n = rtmsg_len(msg);
 383 #endif
 384         }
 385
 386         lim = msg + n;
 387         for (next = msg; next < lim; next += len) {
 388                 int oldifflags;
 389
 390                 next = get_next_msg(next, lim, 0, &len,
 391                                     RTADV_TYPE2BITMASK(RTM_ADD) |
 392                                     RTADV_TYPE2BITMASK(RTM_DELETE) |
 393                                     RTADV_TYPE2BITMASK(RTM_NEWADDR) |
 394                                     RTADV_TYPE2BITMASK(RTM_DELADDR) |
 395                                     RTADV_TYPE2BITMASK(RTM_IFINFO));
 396                 if (len == 0)
 397                         break;
 398                 type = rtmsg_type(next);
 399                 switch (type) {
 400                 case RTM_ADD:
 401                 case RTM_DELETE:
 402                         ifindex = get_rtm_ifindex(next);
 403                         break;
 404                 case RTM_NEWADDR:
 405                 case RTM_DELADDR:
 406                         ifindex = get_ifam_ifindex(next);
 407                         break;
 408                 case RTM_IFINFO:
 409                         ifindex = get_ifm_ifindex(next);
 410                         break;
 411                 default:
 412                         /* should not reach here */
 413                         if (dflag > 1) {
 414                                 syslog(LOG_DEBUG,
 415                                        "<%s:%d> unknown rtmsg %d on %s",
 416                                        __FUNCTION__, __LINE__, type,
 417                                        if_indextoname(ifindex, ifname));
 418                         }
 419                         continue;
 420                 }
 421
 422                 if ((rai = if_indextorainfo(ifindex)) == NULL) {
 423                         if (dflag > 1) {
 424                                 syslog(LOG_DEBUG,
 425                                        "<%s> route changed on "
 426                                        "non advertising interface(%s)",
 427                                        __FUNCTION__,
 428                                        if_indextoname(ifindex, ifname));
 429                         }
 430                         continue;
 431                 }
 432                 oldifflags = iflist[ifindex]->ifm_flags;
 433
 434                 switch (type) {
 435                 case RTM_ADD:
 436                         /* init ifflags because it may have changed */
 437                         iflist[ifindex]->ifm_flags =
 438                             if_getflags(ifindex, iflist[ifindex]->ifm_flags);
 439
 440                         if (sflag)
 441                                 break;  /* we aren't interested in prefixes  */
 442
 443                         addr = get_addr(msg);
 444                         plen = get_prefixlen(msg);
 445                         /* sanity check for plen */
 446                         /* as RFC2373, prefixlen is at least 4 */
 447                         if (plen < 4 || plen > 127) {
 448                                 syslog(LOG_INFO, "<%s> new interface route's"
 449                                     "plen %d is invalid for a prefix",
 450                                     __FUNCTION__, plen);
 451                                 break;
 452                         }
 453                         prefix = find_prefix(rai, addr, plen);
 454                         if (prefix) {
 455                                 if (prefix->timer) {
 456                                         /*
 457                                          * If the prefix has been invalidated,
 458                                          * make it available again.
 459                                          */
 460                                         update_prefix(prefix);
 461                                 } else if (dflag > 1) {
 462                                         syslog(LOG_DEBUG,
 463                                             "<%s> new prefix(%s/%d) "
 464                                             "added on %s, "
 465                                             "but it was already in list",
 466                                             __FUNCTION__,
 467                                             inet_ntop(AF_INET6, addr,
 468                                             (char *)addrbuf, INET6_ADDRSTRLEN),
 469                                             plen, rai->ifname);
 470                                 }
 471                                 break;
 472                         }
 473                         make_prefix(rai, ifindex, addr, plen);
 474                         break;
 475                 case RTM_DELETE:
 476                         /* init ifflags because it may have changed */
 477                         iflist[ifindex]->ifm_flags =
 478                             if_getflags(ifindex, iflist[ifindex]->ifm_flags);
 479
 480                         if (sflag)
 481                                 break;
 482
 483                         addr = get_addr(msg);
 484                         plen = get_prefixlen(msg);
 485                         /* sanity check for plen */
 486                         /* as RFC2373, prefixlen is at least 4 */
 487                         if (plen < 4 || plen > 127) {
 488                                 syslog(LOG_INFO,
 489                                     "<%s> deleted interface route's "
 490                                     "plen %d is invalid for a prefix",
 491                                     __FUNCTION__, plen);
 492                                 break;
 493                         }
 494                         prefix = find_prefix(rai, addr, plen);
 495                         if (prefix == NULL) {
 496                                 if (dflag > 1) {
 497                                         syslog(LOG_DEBUG,
 498                                             "<%s> prefix(%s/%d) was "
 499                                             "deleted on %s, "
 500                                             "but it was not in list",
 501                                             __FUNCTION__,
 502                                             inet_ntop(AF_INET6, addr,
 503                                             (char *)addrbuf, INET6_ADDRSTRLEN),
 504                                             plen, rai->ifname);
 505                                 }
 506                                 break;
 507                         }
 508                         invalidate_prefix(prefix);
 509                         break;
 510                 case RTM_NEWADDR:
 511                 case RTM_DELADDR:
 512                         /* init ifflags because it may have changed */
 513                         iflist[ifindex]->ifm_flags =
 514                             if_getflags(ifindex, iflist[ifindex]->ifm_flags);
 515                         break;
 516                 case RTM_IFINFO:
 517                         iflist[ifindex]->ifm_flags = get_ifm_flags(next);
 518                         break;
 519                 default:
 520                         /* should not reach here */
 521                         if (dflag > 1) {
 522                                 syslog(LOG_DEBUG,
 523                                     "<%s:%d> unknown rtmsg %d on %s",
 524                                     __FUNCTION__, __LINE__, type,
 525                                     if_indextoname(ifindex, ifname));
 526                         }
 527                         return;
 528                 }
 529
 530                 /* check if an interface flag is changed */
 531                 if ((oldifflags & IFF_UP) != 0 &&       /* UP to DOWN */
 532                     (iflist[ifindex]->ifm_flags & IFF_UP) == 0) {
 533                         syslog(LOG_INFO,
 534                             "<%s> interface %s becomes down. stop timer.",
 535                             __FUNCTION__, rai->ifname);
 536                         rtadvd_remove_timer(&rai->timer);
 537                 } else if ((oldifflags & IFF_UP) == 0 &&        /* DOWN to UP */
 538                          (iflist[ifindex]->ifm_flags & IFF_UP) != 0) {
 539                         syslog(LOG_INFO,
 540                             "<%s> interface %s becomes up. restart timer.",
 541                             __FUNCTION__, rai->ifname);
 542
 543                         rai->initcounter = 0; /* reset the counter */
 544                         rai->waiting = 0; /* XXX */
 545                         rai->timer = rtadvd_add_timer(ra_timeout,
 546                             ra_timer_update, rai, rai);
 547                         ra_timer_update((void *)rai, &rai->timer->tm);
 548                         rtadvd_set_timer(&rai->timer->tm, rai->timer);
 549                 }
 550         }
 551
 552         return;
 553 }
 554
 555 void
 556 rtadvd_input()
 557 {
 558         int i;
 559         int *hlimp = NULL;
 560 #ifdef OLDRAWSOCKET
 561         struct ip6_hdr *ip;
 562 #endif
 563         struct icmp6_hdr *icp;
 564         int ifindex = 0;
 565         struct cmsghdr *cm;
 566         struct in6_pktinfo *pi = NULL;
 567         u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
 568         struct in6_addr dst = in6addr_any;
 569
 570         /*
 571          * Get message. We reset msg_controllen since the field could
 572          * be modified if we had received a message before setting
 573          * receive options.
 574          */
 575         rcvmhdr.msg_controllen = rcvcmsgbuflen;
 576         if ((i = recvmsg(sock, &rcvmhdr, 0)) < 0)
 577                 return;
 578
 579         /* extract optional information via Advanced API */
 580         for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr);
 581              cm;
 582              cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) {
 583                 if (cm->cmsg_level == IPPROTO_IPV6 &&
 584                     cm->cmsg_type == IPV6_PKTINFO &&
 585                     cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) {
 586                         pi = (struct in6_pktinfo *)(CMSG_DATA(cm));
 587                         ifindex = pi->ipi6_ifindex;
 588                         dst = pi->ipi6_addr;
 589                 }
 590                 if (cm->cmsg_level == IPPROTO_IPV6 &&
 591                     cm->cmsg_type == IPV6_HOPLIMIT &&
 592                     cm->cmsg_len == CMSG_LEN(sizeof(int)))
 593                         hlimp = (int *)CMSG_DATA(cm);
 594         }
 595         if (ifindex == 0) {
 596                 syslog(LOG_ERR,
 597                        "<%s> failed to get receiving interface",
 598                        __FUNCTION__);
 599                 return;
 600         }
 601         if (hlimp == NULL) {
 602                 syslog(LOG_ERR,
 603                        "<%s> failed to get receiving hop limit",
 604                        __FUNCTION__);
 605                 return;
 606         }
 607
 608         /*
 609          * If we happen to receive data on an interface which is now down,
 610          * just discard the data.
 611          */
 612         if ((iflist[pi->ipi6_ifindex]->ifm_flags & IFF_UP) == 0) {
 613                 syslog(LOG_INFO,
 614                        "<%s> received data on a disabled interface (%s)",
 615                        __FUNCTION__,
 616                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 617                 return;
 618         }
 619
 620 #ifdef OLDRAWSOCKET
 621         if (i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) {
 622                 syslog(LOG_ERR,
 623                        "<%s> packet size(%d) is too short",
 624                        __FUNCTION__, i);
 625                 return;
 626         }
 627
 628         ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base;
 629         icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */
 630 #else
 631         if (i < sizeof(struct icmp6_hdr)) {
 632                 syslog(LOG_ERR,
 633                        "<%s> packet size(%d) is too short",
 634                        __FUNCTION__, i);
 635                 return;
 636         }
 637
 638         icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base;
 639 #endif
 640
 641         switch (icp->icmp6_type) {
 642         case ND_ROUTER_SOLICIT:
 643                 /*
 644                  * Message verification - RFC-2461 6.1.1
 645                  * XXX: these checks must be done in the kernel as well,
 646                  *      but we can't completely rely on them.
 647                  */
 648                 if (*hlimp != 255) {
 649                         syslog(LOG_NOTICE,
 650                             "<%s> RS with invalid hop limit(%d) "
 651                             "received from %s on %s",
 652                             __FUNCTION__, *hlimp,
 653                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 654                             INET6_ADDRSTRLEN),
 655                             if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 656                         return;
 657                 }
 658                 if (icp->icmp6_code) {
 659                         syslog(LOG_NOTICE,
 660                             "<%s> RS with invalid ICMP6 code(%d) "
 661                             "received from %s on %s",
 662                             __FUNCTION__, icp->icmp6_code,
 663                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 664                             INET6_ADDRSTRLEN),
 665                             if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 666                         return;
 667                 }
 668                 if (i < sizeof(struct nd_router_solicit)) {
 669                         syslog(LOG_NOTICE,
 670                             "<%s> RS from %s on %s does not have enough "
 671                             "length (len = %d)",
 672                             __FUNCTION__,
 673                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 674                             INET6_ADDRSTRLEN),
 675                             if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
 676                         return;
 677                 }
 678                 rs_input(i, (struct nd_router_solicit *)icp, pi, &from);
 679                 break;
 680         case ND_ROUTER_ADVERT:
 681                 /*
 682                  * Message verification - RFC-2461 6.1.2
 683                  * XXX: there's a same dilemma as above...
 684                  */
 685                 if (*hlimp != 255) {
 686                         syslog(LOG_NOTICE,
 687                             "<%s> RA with invalid hop limit(%d) "
 688                             "received from %s on %s",
 689                             __FUNCTION__, *hlimp,
 690                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 691                             INET6_ADDRSTRLEN),
 692                             if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 693                         return;
 694                 }
 695                 if (icp->icmp6_code) {
 696                         syslog(LOG_NOTICE,
 697                             "<%s> RA with invalid ICMP6 code(%d) "
 698                             "received from %s on %s",
 699                             __FUNCTION__, icp->icmp6_code,
 700                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 701                             INET6_ADDRSTRLEN),
 702                             if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 703                         return;
 704                 }
 705                 if (i < sizeof(struct nd_router_advert)) {
 706                         syslog(LOG_NOTICE,
 707                             "<%s> RA from %s on %s does not have enough "
 708                             "length (len = %d)",
 709                             __FUNCTION__,
 710                             inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 711                             INET6_ADDRSTRLEN),
 712                             if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
 713                         return;
 714                 }
 715                 ra_input(i, (struct nd_router_advert *)icp, pi, &from);
 716                 break;
 717         case ICMP6_ROUTER_RENUMBERING:
 718                 if (accept_rr == 0) {
 719                         syslog(LOG_ERR, "<%s> received a router renumbering "
 720                             "message, but not allowed to be accepted",
 721                             __FUNCTION__);
 722                         break;
 723                 }
 724                 rr_input(i, (struct icmp6_router_renum *)icp, pi, &from,
 725                          &dst);
 726                 break;
 727         default:
 728                 /*
 729                  * Note that this case is POSSIBLE, especially just
 730                  * after invocation of the daemon. This is because we
 731                  * could receive message after opening the socket and
 732                  * before setting ICMP6 type filter(see sock_open()).
 733                  */
 734                 syslog(LOG_ERR, "<%s> invalid icmp type(%d)",
 735                     __FUNCTION__, icp->icmp6_type);
 736                 return;
 737         }
 738
 739         return;
 740 }
 741
 742 static void
 743 rs_input(int len, struct nd_router_solicit *rs,
 744          struct in6_pktinfo *pi, struct sockaddr_in6 *from)
 745 {
 746         u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
 747         union nd_opts ndopts;
 748         struct rainfo *ra;
 749
 750         syslog(LOG_DEBUG,
 751                "<%s> RS received from %s on %s",
 752                __FUNCTION__,
 753                inet_ntop(AF_INET6, &from->sin6_addr,
 754                          ntopbuf, INET6_ADDRSTRLEN),
 755                if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 756
 757         /* ND option check */
 758         memset(&ndopts, 0, sizeof(ndopts));
 759         if (nd6_options((struct nd_opt_hdr *)(rs + 1),
 760                         len - sizeof(struct nd_router_solicit),
 761                          &ndopts, NDOPT_FLAG_SRCLINKADDR)) {
 762                 syslog(LOG_DEBUG,
 763                        "<%s> ND option check failed for an RS from %s on %s",
 764                        __FUNCTION__,
 765                        inet_ntop(AF_INET6, &from->sin6_addr,
 766                                  ntopbuf, INET6_ADDRSTRLEN),
 767                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 768                 return;
 769         }
 770
 771         /*
 772          * If the IP source address is the unspecified address, there
 773          * must be no source link-layer address option in the message.
 774          * (RFC-2461 6.1.1)
 775          */
 776         if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) &&
 777             ndopts.nd_opts_src_lladdr) {
 778                 syslog(LOG_ERR,
 779                        "<%s> RS from unspecified src on %s has a link-layer"
 780                        " address option",
 781                        __FUNCTION__,
 782                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 783                 goto done;
 784         }
 785
 786         ra = ralist;
 787         while (ra != NULL) {
 788                 if (pi->ipi6_ifindex == ra->ifindex)
 789                         break;
 790                 ra = ra->next;
 791         }
 792         if (ra == NULL) {
 793                 syslog(LOG_INFO,
 794                        "<%s> RS received on non advertising interface(%s)",
 795                        __FUNCTION__,
 796                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 797                 goto done;
 798         }
 799
 800         ra->rsinput++;          /* increment statistics */
 801
 802         /*
 803          * Decide whether to send RA according to the rate-limit
 804          * consideration.
 805          */
 806         {
 807                 long delay;     /* must not be greater than 1000000 */
 808                 struct timeval interval, now, min_delay, tm_tmp, *rest;
 809                 struct soliciter *sol;
 810
 811                 /*
 812                  * record sockaddr waiting for RA, if possible
 813                  */
 814                 sol = (struct soliciter *)malloc(sizeof(*sol));
 815                 if (sol) {
 816                         sol->addr = *from;
 817                         /*XXX RFC2553 need clarification on flowinfo */
 818                         sol->addr.sin6_flowinfo = 0;
 819                         sol->next = ra->soliciter;
 820                         ra->soliciter = sol->next;
 821                 }
 822
 823                 /*
 824                  * If there is already a waiting RS packet, don't
 825                  * update the timer.
 826                  */
 827                 if (ra->waiting++)
 828                         goto done;
 829
 830                 /*
 831                  * Compute a random delay. If the computed value
 832                  * corresponds to a time later than the time the next
 833                  * multicast RA is scheduled to be sent, ignore the random
 834                  * delay and send the advertisement at the
 835                  * already-scheduled time. RFC-2461 6.2.6
 836                  */
 837                 delay = random() % MAX_RA_DELAY_TIME;
 838                 interval.tv_sec = 0;
 839                 interval.tv_usec = delay;
 840                 rest = rtadvd_timer_rest(ra->timer);
 841                 if (TIMEVAL_LT(*rest, interval)) {
 842                         syslog(LOG_DEBUG,
 843                                "<%s> random delay is larger than "
 844                                "the rest of normal timer",
 845                                __FUNCTION__);
 846                         interval = *rest;
 847                 }
 848
 849                 /*
 850                  * If we sent a multicast Router Advertisement within
 851                  * the last MIN_DELAY_BETWEEN_RAS seconds, schedule
 852                  * the advertisement to be sent at a time corresponding to
 853                  * MIN_DELAY_BETWEEN_RAS plus the random value after the
 854                  * previous advertisement was sent.
 855                  */
 856                 gettimeofday(&now, NULL);
 857                 TIMEVAL_SUB(&now, &ra->lastsent, &tm_tmp);
 858                 min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS;
 859                 min_delay.tv_usec = 0;
 860                 if (TIMEVAL_LT(tm_tmp, min_delay)) {
 861                         TIMEVAL_SUB(&min_delay, &tm_tmp, &min_delay);
 862                         TIMEVAL_ADD(&min_delay, &interval, &interval);
 863                 }
 864                 rtadvd_set_timer(&interval, ra->timer);
 865                 goto done;
 866         }
 867
 868   done:
 869         free_ndopts(&ndopts);
 870         return;
 871 }
 872
 873 static void
 874 ra_input(int len, struct nd_router_advert *ra,
 875          struct in6_pktinfo *pi, struct sockaddr_in6 *from)
 876 {
 877         struct rainfo *rai;
 878         u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
 879         union nd_opts ndopts;
 880         char *on_off[] = {"OFF", "ON"};
 881         u_int32_t reachabletime, retranstimer, mtu;
 882         int inconsistent = 0;
 883
 884         syslog(LOG_DEBUG,
 885                "<%s> RA received from %s on %s",
 886                __FUNCTION__,
 887                inet_ntop(AF_INET6, &from->sin6_addr,
 888                          ntopbuf, INET6_ADDRSTRLEN),
 889                if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 890
 891         /* ND option check */
 892         memset(&ndopts, 0, sizeof(ndopts));
 893         if (nd6_options((struct nd_opt_hdr *)(ra + 1),
 894                         len - sizeof(struct nd_router_advert),
 895                         &ndopts, NDOPT_FLAG_SRCLINKADDR |
 896                         NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU)) {
 897                 syslog(LOG_ERR,
 898                        "<%s> ND option check failed for an RA from %s on %s",
 899                        __FUNCTION__,
 900                        inet_ntop(AF_INET6, &from->sin6_addr,
 901                                  ntopbuf, INET6_ADDRSTRLEN),
 902                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 903                 return;
 904         }
 905
 906         /*
 907          * RA consistency check according to RFC-2461 6.2.7
 908          */
 909         if ((rai = if_indextorainfo(pi->ipi6_ifindex)) == 0) {
 910                 syslog(LOG_INFO,
 911                        "<%s> received RA from %s on non-advertising"
 912                        " interface(%s)",
 913                        __FUNCTION__,
 914                        inet_ntop(AF_INET6, &from->sin6_addr,
 915                                  ntopbuf, INET6_ADDRSTRLEN),
 916                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 917                 goto done;
 918         }
 919         rai->rainput++;         /* increment statistics */
 920
 921         /* Cur Hop Limit value */
 922         if (ra->nd_ra_curhoplimit && rai->hoplimit &&
 923             ra->nd_ra_curhoplimit != rai->hoplimit) {
 924                 syslog(LOG_INFO,
 925                        "<%s> CurHopLimit inconsistent on %s:"
 926                        " %d from %s, %d from us",
 927                        __FUNCTION__,
 928                        rai->ifname,
 929                        ra->nd_ra_curhoplimit,
 930                        inet_ntop(AF_INET6, &from->sin6_addr,
 931                                  ntopbuf, INET6_ADDRSTRLEN),
 932                        rai->hoplimit);
 933                 inconsistent++;
 934         }
 935         /* M flag */
 936         if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) !=
 937             rai->managedflg) {
 938                 syslog(LOG_INFO,
 939                        "<%s> M flag inconsistent on %s:"
 940                        " %s from %s, %s from us",
 941                        __FUNCTION__,
 942                        rai->ifname,
 943                        on_off[!rai->managedflg],
 944                        inet_ntop(AF_INET6, &from->sin6_addr,
 945                                  ntopbuf, INET6_ADDRSTRLEN),
 946                        on_off[rai->managedflg]);
 947                 inconsistent++;
 948         }
 949         /* O flag */
 950         if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) !=
 951             rai->otherflg) {
 952                 syslog(LOG_INFO,
 953                        "<%s> O flag inconsistent on %s:"
 954                        " %s from %s, %s from us",
 955                        __FUNCTION__,
 956                        rai->ifname,
 957                        on_off[!rai->otherflg],
 958                        inet_ntop(AF_INET6, &from->sin6_addr,
 959                                  ntopbuf, INET6_ADDRSTRLEN),
 960                        on_off[rai->otherflg]);
 961                 inconsistent++;
 962         }
 963         /* Reachable Time */
 964         reachabletime = ntohl(ra->nd_ra_reachable);
 965         if (reachabletime && rai->reachabletime &&
 966             reachabletime != rai->reachabletime) {
 967                 syslog(LOG_INFO,
 968                        "<%s> ReachableTime inconsistent on %s:"
 969                        " %d from %s, %d from us",
 970                        __FUNCTION__,
 971                        rai->ifname,
 972                        reachabletime,
 973                        inet_ntop(AF_INET6, &from->sin6_addr,
 974                                  ntopbuf, INET6_ADDRSTRLEN),
 975                        rai->reachabletime);
 976                 inconsistent++;
 977         }
 978         /* Retrans Timer */
 979         retranstimer = ntohl(ra->nd_ra_retransmit);
 980         if (retranstimer && rai->retranstimer &&
 981             retranstimer != rai->retranstimer) {
 982                 syslog(LOG_INFO,
 983                        "<%s> RetranceTimer inconsistent on %s:"
 984                        " %d from %s, %d from us",
 985                        __FUNCTION__,
 986                        rai->ifname,
 987                        retranstimer,
 988                        inet_ntop(AF_INET6, &from->sin6_addr,
 989                                  ntopbuf, INET6_ADDRSTRLEN),
 990                        rai->retranstimer);
 991                 inconsistent++;
 992         }
 993         /* Values in the MTU options */
 994         if (ndopts.nd_opts_mtu) {
 995                 mtu = ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu);
 996                 if (mtu && rai->linkmtu && mtu != rai->linkmtu) {
 997                         syslog(LOG_INFO,
 998                                "<%s> MTU option value inconsistent on %s:"
 999                                " %d from %s, %d from us",
1000                                __FUNCTION__,
1001                                rai->ifname, mtu,
1002                                inet_ntop(AF_INET6, &from->sin6_addr,
1003                                          ntopbuf, INET6_ADDRSTRLEN),
1004                                rai->linkmtu);
1005                         inconsistent++;
1006                 }
1007         }
1008         /* Preferred and Valid Lifetimes for prefixes */
1009         {
1010                 struct nd_optlist *optp = ndopts.nd_opts_list;
1011
1012                 if (ndopts.nd_opts_pi) {
1013                         if (prefix_check(ndopts.nd_opts_pi, rai, from))
1014                                 inconsistent++;
1015                 }
1016                 while (optp) {
1017                         if (prefix_check((struct nd_opt_prefix_info *)optp->opt,
1018                                          rai, from))
1019                                 inconsistent++;
1020                         optp = optp->next;
1021                 }
1022         }
1023
1024         if (inconsistent)
1025                 rai->rainconsistent++;
1026
1027   done:
1028         free_ndopts(&ndopts);
1029         return;
1030 }
1031
1032 /* return a non-zero value if the received prefix is inconsitent with ours */
1033 static int
1034 prefix_check(struct nd_opt_prefix_info *pinfo,
1035              struct rainfo *rai, struct sockaddr_in6 *from)
1036 {
1037         u_int32_t preferred_time, valid_time;
1038         struct prefix *pp;
1039         int inconsistent = 0;
1040         u_char ntopbuf[INET6_ADDRSTRLEN], prefixbuf[INET6_ADDRSTRLEN];
1041         struct timeval now;
1042
1043 #if 0                           /* impossible */
1044         if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION)
1045                 return(0);
1046 #endif
1047
1048         /*
1049          * log if the adveritsed prefix has link-local scope(sanity check?)
1050          */
1051         if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) {
1052                 syslog(LOG_INFO,
1053                        "<%s> link-local prefix %s/%d is advertised "
1054                        "from %s on %s",
1055                        __FUNCTION__,
1056                        inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1057                                  prefixbuf, INET6_ADDRSTRLEN),
1058                        pinfo->nd_opt_pi_prefix_len,
1059                        inet_ntop(AF_INET6, &from->sin6_addr,
1060                                  ntopbuf, INET6_ADDRSTRLEN),
1061                        rai->ifname);
1062         }
1063
1064         if ((pp = find_prefix(rai, &pinfo->nd_opt_pi_prefix,
1065                               pinfo->nd_opt_pi_prefix_len)) == NULL) {
1066                 syslog(LOG_INFO,
1067                        "<%s> prefix %s/%d from %s on %s is not in our list",
1068                        __FUNCTION__,
1069                        inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1070                                  prefixbuf, INET6_ADDRSTRLEN),
1071                        pinfo->nd_opt_pi_prefix_len,
1072                        inet_ntop(AF_INET6, &from->sin6_addr,
1073                                  ntopbuf, INET6_ADDRSTRLEN),
1074                        rai->ifname);
1075                 return(0);
1076         }
1077
1078         preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time);
1079         if (pp->pltimeexpire) {
1080                 /*
1081                  * The lifetime is decremented in real time, so we should
1082                  * compare the expiration time.
1083                  * (RFC 2461 Section 6.2.7.)
1084                  * XXX: can we really expect that all routers on the link
1085                  * have synchronized clocks?
1086                  */
1087                 gettimeofday(&now, NULL);
1088                 preferred_time += now.tv_sec;
1089
1090                 if (rai->clockskew &&
1091                     abs(preferred_time - pp->pltimeexpire) > rai->clockskew) {
1092                         syslog(LOG_INFO,
1093                                "<%s> prefeerred lifetime for %s/%d"
1094                                " (decr. in real time) inconsistent on %s:"
1095                                " %d from %s, %ld from us",
1096                                __FUNCTION__,
1097                                inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1098                                          prefixbuf, INET6_ADDRSTRLEN),
1099                                pinfo->nd_opt_pi_prefix_len,
1100                                rai->ifname, preferred_time,
1101                                inet_ntop(AF_INET6, &from->sin6_addr,
1102                                          ntopbuf, INET6_ADDRSTRLEN),
1103                                pp->pltimeexpire);
1104                         inconsistent++;
1105                 }
1106         } else if (preferred_time != pp->preflifetime) {
1107                 syslog(LOG_INFO,
1108                        "<%s> prefeerred lifetime for %s/%d"
1109                        " inconsistent on %s:"
1110                        " %d from %s, %d from us",
1111                        __FUNCTION__,
1112                        inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1113                                  prefixbuf, INET6_ADDRSTRLEN),
1114                        pinfo->nd_opt_pi_prefix_len,
1115                        rai->ifname, preferred_time,
1116                        inet_ntop(AF_INET6, &from->sin6_addr,
1117                                  ntopbuf, INET6_ADDRSTRLEN),
1118                        pp->preflifetime);
1119         }
1120
1121         valid_time = ntohl(pinfo->nd_opt_pi_valid_time);
1122         if (pp->vltimeexpire) {
1123                 gettimeofday(&now, NULL);
1124                 valid_time += now.tv_sec;
1125
1126                 if (rai->clockskew &&
1127                     abs(valid_time - pp->vltimeexpire) > rai->clockskew) {
1128                         syslog(LOG_INFO,
1129                                "<%s> valid lifetime for %s/%d"
1130                                " (decr. in real time) inconsistent on %s:"
1131                                " %d from %s, %ld from us",
1132                                __FUNCTION__,
1133                                inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1134                                          prefixbuf, INET6_ADDRSTRLEN),
1135                                pinfo->nd_opt_pi_prefix_len,
1136                                rai->ifname, preferred_time,
1137                                inet_ntop(AF_INET6, &from->sin6_addr,
1138                                          ntopbuf, INET6_ADDRSTRLEN),
1139                                pp->vltimeexpire);
1140                         inconsistent++;
1141                 }
1142         } else if (valid_time != pp->validlifetime) {
1143                 syslog(LOG_INFO,
1144                        "<%s> valid lifetime for %s/%d"
1145                        " inconsistent on %s:"
1146                        " %d from %s, %d from us",
1147                        __FUNCTION__,
1148                        inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1149                                  prefixbuf, INET6_ADDRSTRLEN),
1150                        pinfo->nd_opt_pi_prefix_len,
1151                        rai->ifname, valid_time,
1152                        inet_ntop(AF_INET6, &from->sin6_addr,
1153                                  ntopbuf, INET6_ADDRSTRLEN),
1154                        pp->validlifetime);
1155                 inconsistent++;
1156         }
1157
1158         return(inconsistent);
1159 }
1160
1161 struct prefix *
1162 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen)
1163 {
1164         struct prefix *pp;
1165         int bytelen, bitlen;
1166
1167         for (pp = rai->prefix.next; pp != &rai->prefix; pp = pp->next) {
1168                 if (plen != pp->prefixlen)
1169                         continue;
1170                 bytelen = plen / 8;
1171                 bitlen = plen % 8;
1172                 if (memcmp((void *)prefix, (void *)&pp->prefix, bytelen))
1173                         continue;
1174                 if (prefix->s6_addr[bytelen] >> (8 - bitlen) ==
1175                     pp->prefix.s6_addr[bytelen] >> (8 - bitlen))
1176                         return(pp);
1177         }
1178
1179         return(NULL);
1180 }
1181
1182 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */
1183 int
1184 prefix_match(struct in6_addr *p0, int plen0,
1185              struct in6_addr *p1, int plen1)
1186 {
1187         int bytelen, bitlen;
1188
1189         if (plen0 < plen1)
1190                 return(0);
1191         bytelen = plen1 / 8;
1192         bitlen = plen1 % 8;
1193         if (memcmp((void *)p0, (void *)p1, bytelen))
1194                 return(0);
1195         if (p0->s6_addr[bytelen] >> (8 - bitlen) ==
1196             p1->s6_addr[bytelen] >> (8 - bitlen))
1197                 return(1);
1198
1199         return(0);
1200 }
1201
1202 static int
1203 nd6_options(struct nd_opt_hdr *hdr, int limit,
1204             union nd_opts *ndopts, u_int32_t optflags)
1205 {
1206         int optlen = 0;
1207
1208         for (; limit > 0; limit -= optlen) {
1209                 if (limit < sizeof(struct nd_opt_hdr)) {
1210                         syslog(LOG_INFO, "<%s> short option header", __FUNCTION__);
1211                         goto bad;
1212                 }
1213
1214                 hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen);
1215                 if (hdr->nd_opt_len == 0) {
1216                         syslog(LOG_INFO,
1217                             "<%s> bad ND option length(0) (type = %d)",
1218                             __FUNCTION__, hdr->nd_opt_type);
1219                         goto bad;
1220                 }
1221                 optlen = hdr->nd_opt_len << 3;
1222                 if (optlen > limit) {
1223                         syslog(LOG_INFO, "<%s> short option", __FUNCTION__);
1224                         goto bad;
1225                 }
1226
1227                 if (hdr->nd_opt_type > ND_OPT_MTU) {
1228                         syslog(LOG_INFO,
1229                             "<%s> unknown ND option(type %d)",
1230                             __FUNCTION__, hdr->nd_opt_type);
1231                         continue;
1232                 }
1233
1234                 if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) {
1235                         syslog(LOG_INFO,
1236                             "<%s> unexpected ND option(type %d)",
1237                                __FUNCTION__, hdr->nd_opt_type);
1238                         continue;
1239                 }
1240
1241                 /*
1242                  * Option length check.  Do it here for all fixed-length
1243                  * options.
1244                  */
1245                 if ((hdr->nd_opt_type == ND_OPT_MTU &&
1246                     (optlen != sizeof(struct nd_opt_mtu))) ||
1247                     ((hdr->nd_opt_type == ND_OPT_PREFIX_INFORMATION &&
1248                     optlen != sizeof(struct nd_opt_prefix_info)))) {
1249                         syslog(LOG_INFO, "<%s> invalid option length",
1250                             __FUNCTION__);
1251                         continue;
1252                 }
1253
1254                 switch (hdr->nd_opt_type) {
1255                 case ND_OPT_SOURCE_LINKADDR:
1256                 case ND_OPT_TARGET_LINKADDR:
1257                 case ND_OPT_REDIRECTED_HEADER:
1258                         break;  /* we don't care about these options */
1259                 case ND_OPT_MTU:
1260                         if (ndopts->nd_opt_array[hdr->nd_opt_type]) {
1261                                 syslog(LOG_INFO,
1262                                     "<%s> duplicated ND option (type = %d)",
1263                                     __FUNCTION__, hdr->nd_opt_type);
1264                         }
1265                         ndopts->nd_opt_array[hdr->nd_opt_type] = hdr;
1266                         break;
1267                 case ND_OPT_PREFIX_INFORMATION:
1268                 {
1269                         struct nd_optlist *pfxlist;
1270
1271                         if (ndopts->nd_opts_pi == 0) {
1272                                 ndopts->nd_opts_pi =
1273                                     (struct nd_opt_prefix_info *)hdr;
1274                                 continue;
1275                         }
1276                         if ((pfxlist = malloc(sizeof(*pfxlist))) == NULL) {
1277                                 syslog(LOG_ERR, "<%s> can't allocate memory",
1278                                     __FUNCTION__);
1279                                 goto bad;
1280                         }
1281                         pfxlist->next = ndopts->nd_opts_list;
1282                         pfxlist->opt = hdr;
1283                         ndopts->nd_opts_list = pfxlist;
1284
1285                         break;
1286                 }
1287                 default:        /* impossible */
1288                         break;
1289                 }
1290         }
1291
1292         return(0);
1293
1294   bad:
1295         free_ndopts(ndopts);
1296
1297         return(-1);
1298 }
1299
1300 static void
1301 free_ndopts(union nd_opts *ndopts)
1302 {
1303         struct nd_optlist *opt = ndopts->nd_opts_list, *next;
1304
1305         while (opt) {
1306                 next = opt->next;
1307                 free(opt);
1308                 opt = next;
1309         }
1310 }
1311
1312 void
1313 sock_open()
1314 {
1315         struct icmp6_filter filt;
1316         struct ipv6_mreq mreq;
1317         struct rainfo *ra = ralist;
1318         int on;
1319         /* XXX: should be max MTU attached to the node */
1320         static u_char answer[1500];
1321
1322         rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1323                                 CMSG_SPACE(sizeof(int));
1324         rcvcmsgbuf = (u_char *)malloc(rcvcmsgbuflen);
1325         if (rcvcmsgbuf == NULL) {
1326                 syslog(LOG_ERR, "<%s> not enough core", __FUNCTION__);
1327                 exit(1);
1328         }
1329
1330         sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1331                                 CMSG_SPACE(sizeof(int));
1332         sndcmsgbuf = (u_char *)malloc(sndcmsgbuflen);
1333         if (sndcmsgbuf == NULL) {
1334                 syslog(LOG_ERR, "<%s> not enough core", __FUNCTION__);
1335                 exit(1);
1336         }
1337
1338         if ((sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
1339                 syslog(LOG_ERR, "<%s> socket: %s", __FUNCTION__,
1340                        strerror(errno));
1341                 exit(1);
1342         }
1343
1344         /* specify to tell receiving interface */
1345         on = 1;
1346 #ifdef IPV6_RECVPKTINFO
1347         if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
1348                        sizeof(on)) < 0) {
1349                 syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s",
1350                        __FUNCTION__, strerror(errno));
1351                 exit(1);
1352         }
1353 #else  /* old adv. API */
1354         if (setsockopt(sock, IPPROTO_IPV6, IPV6_PKTINFO, &on,
1355                        sizeof(on)) < 0) {
1356                 syslog(LOG_ERR, "<%s> IPV6_PKTINFO: %s",
1357                        __FUNCTION__, strerror(errno));
1358                 exit(1);
1359         }
1360 #endif
1361
1362         on = 1;
1363         /* specify to tell value of hoplimit field of received IP6 hdr */
1364 #ifdef IPV6_RECVHOPLIMIT
1365         if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
1366                        sizeof(on)) < 0) {
1367                 syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s",
1368                        __FUNCTION__, strerror(errno));
1369                 exit(1);
1370         }
1371 #else  /* old adv. API */
1372         if (setsockopt(sock, IPPROTO_IPV6, IPV6_HOPLIMIT, &on,
1373                        sizeof(on)) < 0) {
1374                 syslog(LOG_ERR, "<%s> IPV6_HOPLIMIT: %s",
1375                        __FUNCTION__, strerror(errno));
1376                 exit(1);
1377         }
1378 #endif
1379
1380         ICMP6_FILTER_SETBLOCKALL(&filt);
1381         ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt);
1382         ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
1383         if (accept_rr)
1384                 ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt);
1385         if (setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
1386                        sizeof(filt)) < 0) {
1387                 syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s",
1388                        __FUNCTION__, strerror(errno));
1389                 exit(1);
1390         }
1391
1392         /*
1393          * join all routers multicast address on each advertising interface.
1394          */
1395         if (inet_pton(AF_INET6, ALLROUTERS_LINK,
1396                       &mreq.ipv6mr_multiaddr.s6_addr)
1397             != 1) {
1398                 syslog(LOG_ERR, "<%s> inet_pton failed(library bug?)",
1399                        __FUNCTION__);
1400                 exit(1);
1401         }
1402         while (ra) {
1403                 mreq.ipv6mr_interface = ra->ifindex;
1404                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq,
1405                                sizeof(mreq)) < 0) {
1406                         syslog(LOG_ERR, "<%s> IPV6_JOIN_GROUP(link) on %s: %s",
1407                                __FUNCTION__, ra->ifname, strerror(errno));
1408                         exit(1);
1409                 }
1410                 ra = ra->next;
1411         }
1412
1413         /*
1414          * When attending router renumbering, join all-routers site-local
1415          * multicast group.
1416          */
1417         if (accept_rr) {
1418                 if (inet_pton(AF_INET6, ALLROUTERS_SITE,
1419                               &in6a_site_allrouters) != 1) {
1420                         syslog(LOG_ERR, "<%s> inet_pton failed(library bug?)",
1421                                __FUNCTION__);
1422                         exit(1);
1423                 }
1424                 mreq.ipv6mr_multiaddr = in6a_site_allrouters;
1425                 if (mcastif) {
1426                         if ((mreq.ipv6mr_interface = if_nametoindex(mcastif))
1427                             == 0) {
1428                                 syslog(LOG_ERR,
1429                                        "<%s> invalid interface: %s",
1430                                        __FUNCTION__, mcastif);
1431                                 exit(1);
1432                         }
1433                 } else
1434                         mreq.ipv6mr_interface = ralist->ifindex;
1435                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP,
1436                                &mreq, sizeof(mreq)) < 0) {
1437                         syslog(LOG_ERR,
1438                                "<%s> IPV6_JOIN_GROUP(site) on %s: %s",
1439                                __FUNCTION__,
1440                                mcastif ? mcastif : ralist->ifname,
1441                                strerror(errno));
1442                         exit(1);
1443                 }
1444         }
1445
1446         /* initialize msghdr for receiving packets */
1447         rcviov[0].iov_base = (caddr_t)answer;
1448         rcviov[0].iov_len = sizeof(answer);
1449         rcvmhdr.msg_name = (caddr_t)&from;
1450         rcvmhdr.msg_namelen = sizeof(from);
1451         rcvmhdr.msg_iov = rcviov;
1452         rcvmhdr.msg_iovlen = 1;
1453         rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
1454         rcvmhdr.msg_controllen = rcvcmsgbuflen;
1455
1456         /* initialize msghdr for sending packets */
1457         sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
1458         sndmhdr.msg_iov = sndiov;
1459         sndmhdr.msg_iovlen = 1;
1460         sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
1461         sndmhdr.msg_controllen = sndcmsgbuflen;
1462
1463         return;
1464 }
1465
1466 /* open a routing socket to watch the routing table */
1467 static void
1468 rtsock_open()
1469 {
1470         if ((rtsock = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) {
1471                 syslog(LOG_ERR,
1472                        "<%s> socket: %s", __FUNCTION__, strerror(errno));
1473                 exit(1);
1474         }
1475 }
1476
1477 struct rainfo *
1478 if_indextorainfo(int index)
1479 {
1480         struct rainfo *rai = ralist;
1481
1482         for (rai = ralist; rai; rai = rai->next) {
1483                 if (rai->ifindex == index)
1484                         return(rai);
1485         }
1486
1487         return(NULL);           /* search failed */
1488 }
1489
1490 static void
1491 ra_output(rainfo)
1492 struct rainfo *rainfo;
1493 {
1494         int i;
1495         struct cmsghdr *cm;
1496         struct in6_pktinfo *pi;
1497         struct soliciter *sol, *nextsol;
1498
1499         if ((iflist[rainfo->ifindex]->ifm_flags & IFF_UP) == 0) {
1500                 syslog(LOG_DEBUG, "<%s> %s is not up, skip sending RA",
1501                        __FUNCTION__, rainfo->ifname);
1502                 return;
1503         }
1504
1505         make_packet(rainfo);    /* XXX: inefficient */
1506
1507         sndmhdr.msg_name = (caddr_t)&sin6_allnodes;
1508         sndmhdr.msg_iov[0].iov_base = (caddr_t)rainfo->ra_data;
1509         sndmhdr.msg_iov[0].iov_len = rainfo->ra_datalen;
1510
1511         cm = CMSG_FIRSTHDR(&sndmhdr);
1512         /* specify the outgoing interface */
1513         cm->cmsg_level = IPPROTO_IPV6;
1514         cm->cmsg_type = IPV6_PKTINFO;
1515         cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
1516         pi = (struct in6_pktinfo *)CMSG_DATA(cm);
1517         memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr));       /*XXX*/
1518         pi->ipi6_ifindex = rainfo->ifindex;
1519
1520         /* specify the hop limit of the packet */
1521         {
1522                 int hoplimit = 255;
1523
1524                 cm = CMSG_NXTHDR(&sndmhdr, cm);
1525                 cm->cmsg_level = IPPROTO_IPV6;
1526                 cm->cmsg_type = IPV6_HOPLIMIT;
1527                 cm->cmsg_len = CMSG_LEN(sizeof(int));
1528                 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
1529         }
1530
1531         syslog(LOG_DEBUG,
1532                "<%s> send RA on %s, # of waitings = %d",
1533                __FUNCTION__, rainfo->ifname, rainfo->waiting);
1534
1535         i = sendmsg(sock, &sndmhdr, 0);
1536
1537         if (i < 0 || i != rainfo->ra_datalen)  {
1538                 if (i < 0) {
1539                         syslog(LOG_ERR, "<%s> sendmsg on %s: %s",
1540                                __FUNCTION__, rainfo->ifname,
1541                                strerror(errno));
1542                 }
1543         }
1544
1545         /*
1546          * unicast advertisements
1547          * XXX commented out.  reason: though spec does not forbit it, unicast
1548          * advert does not really help
1549          */
1550         for (sol = rainfo->soliciter; sol; sol = nextsol) {
1551                 nextsol = sol->next;
1552
1553 #if 0
1554                 sndmhdr.msg_name = (caddr_t)&sol->addr;
1555                 i = sendmsg(sock, &sndmhdr, 0);
1556                 if (i < 0 || i != rainfo->ra_datalen)  {
1557                         if (i < 0) {
1558                                 syslog(LOG_ERR,
1559                                     "<%s> unicast sendmsg on %s: %s",
1560                                     __FUNCTION__, rainfo->ifname,
1561                                     strerror(errno));
1562                         }
1563                 }
1564 #endif
1565
1566                 sol->next = NULL;
1567                 free(sol);
1568         }
1569         rainfo->soliciter = NULL;
1570
1571         /* update counter */
1572         if (rainfo->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS)
1573                 rainfo->initcounter++;
1574         rainfo->raoutput++;
1575
1576         /* update timestamp */
1577         gettimeofday(&rainfo->lastsent, NULL);
1578
1579         /* reset waiting conter */
1580         rainfo->waiting = 0;
1581 }
1582
1583 /* process RA timer */
1584 struct rtadvd_timer *
1585 ra_timeout(void *data)
1586 {
1587         struct rainfo *rai = (struct rainfo *)data;
1588
1589 #ifdef notyet
1590         /* if necessary, reconstruct the packet. */
1591 #endif
1592
1593         syslog(LOG_DEBUG,
1594                "<%s> RA timer on %s is expired",
1595                __FUNCTION__, rai->ifname);
1596
1597         ra_output(rai);
1598
1599         return(rai->timer);
1600 }
1601
1602 /* update RA timer */
1603 void
1604 ra_timer_update(void *data, struct timeval *tm)
1605 {
1606         struct rainfo *rai = (struct rainfo *)data;
1607         long interval;
1608
1609         /*
1610          * Whenever a multicast advertisement is sent from an interface,
1611          * the timer is reset to a uniformly-distributed random value
1612          * between the interface's configured MinRtrAdvInterval and
1613          * MaxRtrAdvInterval (RFC2461 6.2.4).
1614          */
1615         interval = rai->mininterval;
1616         interval += random() % (rai->maxinterval - rai->mininterval);
1617
1618         /*
1619          * For the first few advertisements (up to
1620          * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen interval
1621          * is greater than MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer
1622          * SHOULD be set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead.
1623          * (RFC-2461 6.2.4)
1624          */
1625         if (rai->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS &&
1626             interval > MAX_INITIAL_RTR_ADVERT_INTERVAL)
1627                 interval = MAX_INITIAL_RTR_ADVERT_INTERVAL;
1628
1629         tm->tv_sec = interval;
1630         tm->tv_usec = 0;
1631
1632         syslog(LOG_DEBUG,
1633                "<%s> RA timer on %s is set to %ld:%ld",
1634                __FUNCTION__, rai->ifname,
1635                (long int)tm->tv_sec, (long int)tm->tv_usec);
1636
1637         return;
1638 }