usr.sbin/rtsold/rtsold.c

   1 /*      $KAME: rtsold.c,v 1.67 2003/05/17 18:16:15 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  * $FreeBSD$
  32  */
  33
  34 #include <sys/types.h>
  35 #include <sys/ioctl.h>
  36 #include <sys/time.h>
  37 #include <sys/socket.h>
  38 #include <sys/param.h>
  39
  40 #include <net/if.h>
  41 #include <net/if_dl.h>
  42 #include <net/if_var.h>
  43
  44 #include <netinet/in.h>
  45 #include <netinet/icmp6.h>
  46 #include <netinet/in_var.h>
  47
  48 #include <netinet6/nd6.h>
  49
  50 #include <signal.h>
  51 #include <unistd.h>
  52 #include <syslog.h>
  53 #include <string.h>
  54 #include <stdlib.h>
  55 #include <stdio.h>
  56 #include <errno.h>
  57 #include <err.h>
  58 #include <stdarg.h>
  59 #include <ifaddrs.h>
  60 #ifdef HAVE_POLL_H
  61 #include <poll.h>
  62 #endif
  63
  64 #include "rtsold.h"
  65
  66 #define RTSOL_DUMPFILE  "/var/run/rtsold.dump";
  67 #define RTSOL_PIDFILE   "/var/run/rtsold.pid";
  68
  69 struct ifinfo *iflist;
  70 struct timeval tm_max = {0x7fffffff, 0x7fffffff};
  71 static int log_upto = 999;
  72 static int fflag = 0;
  73
  74 int Fflag = 0;  /* force setting sysctl parameters */
  75 int aflag = 0;
  76 int dflag = 0;
  77
  78 const char *otherconf_script;
  79 const char *resolvconf_script = "/sbin/resolvconf";
  80
  81 /* protocol constants */
  82 #define MAX_RTR_SOLICITATION_DELAY      1 /* second */
  83 #define RTR_SOLICITATION_INTERVAL       4 /* seconds */
  84 #define MAX_RTR_SOLICITATIONS           3 /* times */
  85
  86 /*
  87  * implementation dependent constants in seconds
  88  * XXX: should be configurable
  89  */
  90 #define PROBE_INTERVAL 60
  91
  92 /* static variables and functions */
  93 static int mobile_node = 0;
  94 static const char *pidfilename = RTSOL_PIDFILE;
  95
  96 #ifndef SMALL
  97 static int do_dump;
  98 static const char *dumpfilename = RTSOL_DUMPFILE;
  99 #endif
 100
 101 #if 0
 102 static int ifreconfig(char *);
 103 #endif
 104
 105 static int make_packet(struct ifinfo *);
 106 static struct timeval *rtsol_check_timer(void);
 107
 108 #ifndef SMALL
 109 static void rtsold_set_dump_file(int);
 110 #endif
 111 static void usage(void);
 112
 113 int
 114 main(int argc, char **argv)
 115 {
 116         int s, ch, once = 0;
 117         struct timeval *timeout;
 118         const char *opts;
 119 #ifdef HAVE_POLL_H
 120         struct pollfd set[2];
 121 #else
 122         fd_set *fdsetp, *selectfdp;
 123         int fdmasks;
 124         int maxfd;
 125 #endif
 126         int rtsock;
 127
 128 #ifndef SMALL
 129         /* rtsold */
 130         opts = "adDfFm1O:P:R:";
 131 #else
 132         /* rtsol */
 133         opts = "adDFO:P:R:";
 134         fflag = 1;
 135         once = 1;
 136 #endif
 137         while ((ch = getopt(argc, argv, opts)) != -1) {
 138                 switch (ch) {
 139                 case 'a':
 140                         aflag = 1;
 141                         break;
 142                 case 'd':
 143                         dflag = 1;
 144                         break;
 145                 case 'D':
 146                         dflag = 2;
 147                         break;
 148                 case 'f':
 149                         fflag = 1;
 150                         break;
 151                 case 'F':
 152                         Fflag = 1;
 153                         break;
 154                 case 'm':
 155                         mobile_node = 1;
 156                         break;
 157                 case '1':
 158                         once = 1;
 159                         break;
 160                 case 'O':
 161                         otherconf_script = optarg;
 162                         break;
 163                 case 'P':
 164                         pidfilename = optarg;
 165                         break;
 166                 case 'R':
 167                         resolvconf_script = optarg;
 168                         break;
 169                 default:
 170                         usage();
 171                         exit(1);
 172                 }
 173         }
 174         argc -= optind;
 175         argv += optind;
 176
 177         if ((!aflag && argc == 0) || (aflag && argc != 0)) {
 178                 usage();
 179                 exit(1);
 180         }
 181
 182         /* set log level */
 183         if (dflag == 0)
 184                 log_upto = LOG_NOTICE;
 185         if (!fflag) {
 186                 char *ident;
 187
 188                 ident = strrchr(argv[0], '/');
 189                 if (!ident)
 190                         ident = argv[0];
 191                 else
 192                         ident++;
 193                 openlog(ident, LOG_NDELAY|LOG_PID, LOG_DAEMON);
 194                 if (log_upto >= 0)
 195                         setlogmask(LOG_UPTO(log_upto));
 196         }
 197
 198         if (otherconf_script && *otherconf_script != '/') {
 199                 errx(1, "configuration script (%s) must be an absolute path",
 200                     otherconf_script);
 201         }
 202         if (resolvconf_script && *resolvconf_script != '/') {
 203                 errx(1, "configuration script (%s) must be an absolute path",
 204                     resolvconf_script);
 205         }
 206         if (pidfilename && *pidfilename != '/') {
 207                 errx(1, "pid filename (%s) must be an absolute path",
 208                     pidfilename);
 209         }
 210 #ifndef HAVE_ARC4RANDOM
 211         /* random value initialization */
 212         srandom((u_long)time(NULL));
 213 #endif
 214
 215         if (Fflag) {
 216                 setinet6sysctl(IPV6CTL_FORWARDING, 0);
 217         } else {
 218                 /* warn if forwarding is up */
 219                 if (getinet6sysctl(IPV6CTL_FORWARDING))
 220                         warnx("kernel is configured as a router, not a host");
 221         }
 222
 223 #ifndef SMALL
 224         /* initialization to dump internal status to a file */
 225         signal(SIGUSR1, rtsold_set_dump_file);
 226 #endif
 227
 228         if (!fflag)
 229                 daemon(0, 0);           /* act as a daemon */
 230
 231         /*
 232          * Open a socket for sending RS and receiving RA.
 233          * This should be done before calling ifinit(), since the function
 234          * uses the socket.
 235          */
 236         if ((s = sockopen()) < 0) {
 237                 warnmsg(LOG_ERR, __func__, "failed to open a socket");
 238                 exit(1);
 239         }
 240 #ifdef HAVE_POLL_H
 241         set[0].fd = s;
 242         set[0].events = POLLIN;
 243 #else
 244         maxfd = s;
 245 #endif
 246
 247 #ifdef HAVE_POLL_H
 248         set[1].fd = -1;
 249 #endif
 250
 251         if ((rtsock = rtsock_open()) < 0) {
 252                 warnmsg(LOG_ERR, __func__, "failed to open a socket");
 253                 exit(1);
 254         }
 255 #ifdef HAVE_POLL_H
 256         set[1].fd = rtsock;
 257         set[1].events = POLLIN;
 258 #else
 259         if (rtsock > maxfd)
 260                 maxfd = rtsock;
 261 #endif
 262
 263 #ifndef HAVE_POLL_H
 264         fdmasks = howmany(maxfd + 1, NFDBITS) * sizeof(fd_mask);
 265         if ((fdsetp = malloc(fdmasks)) == NULL) {
 266                 warnmsg(LOG_ERR, __func__, "malloc");
 267                 exit(1);
 268         }
 269         if ((selectfdp = malloc(fdmasks)) == NULL) {
 270                 warnmsg(LOG_ERR, __func__, "malloc");
 271                 exit(1);
 272         }
 273 #endif
 274
 275         /* configuration per interface */
 276         if (ifinit()) {
 277                 warnmsg(LOG_ERR, __func__,
 278                     "failed to initialize interfaces");
 279                 exit(1);
 280         }
 281         if (aflag)
 282                 argv = autoifprobe();
 283         while (argv && *argv) {
 284                 if (ifconfig(*argv)) {
 285                         warnmsg(LOG_ERR, __func__,
 286                             "failed to initialize %s", *argv);
 287                         exit(1);
 288                 }
 289                 argv++;
 290         }
 291
 292         /* setup for probing default routers */
 293         if (probe_init()) {
 294                 warnmsg(LOG_ERR, __func__,
 295                     "failed to setup for probing routers");
 296                 exit(1);
 297                 /*NOTREACHED*/
 298         }
 299
 300         /* dump the current pid */
 301         if (!once) {
 302                 pid_t pid = getpid();
 303                 FILE *fp;
 304
 305                 if ((fp = fopen(pidfilename, "w")) == NULL)
 306                         warnmsg(LOG_ERR, __func__,
 307                             "failed to open a pid log file(%s): %s",
 308                             pidfilename, strerror(errno));
 309                 else {
 310                         fprintf(fp, "%d\n", pid);
 311                         fclose(fp);
 312                 }
 313         }
 314 #ifndef HAVE_POLL_H
 315         memset(fdsetp, 0, fdmasks);
 316         FD_SET(s, fdsetp);
 317         FD_SET(rtsock, fdsetp);
 318 #endif
 319         while (1) {             /* main loop */
 320                 int e;
 321
 322 #ifndef HAVE_POLL_H
 323                 memcpy(selectfdp, fdsetp, fdmasks);
 324 #endif
 325
 326 #ifndef SMALL
 327                 if (do_dump) {  /* SIGUSR1 */
 328                         do_dump = 0;
 329                         rtsold_dump_file(dumpfilename);
 330                 }
 331 #endif
 332
 333                 timeout = rtsol_check_timer();
 334
 335                 if (once) {
 336                         struct ifinfo *ifi;
 337
 338                         /* if we have no timeout, we are done (or failed) */
 339                         if (timeout == NULL)
 340                                 break;
 341
 342                         /* if all interfaces have got RA packet, we are done */
 343                         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 344                                 if (ifi->state != IFS_DOWN && ifi->racnt == 0)
 345                                         break;
 346                         }
 347                         if (ifi == NULL)
 348                                 break;
 349                 }
 350 #ifdef HAVE_POLL_H
 351                 e = poll(set, 2, timeout ? (timeout->tv_sec * 1000 + timeout->tv_usec / 1000) : INFTIM);
 352 #else
 353                 e = select(maxfd + 1, selectfdp, NULL, NULL, timeout);
 354 #endif
 355                 if (e < 1) {
 356                         if (e < 0 && errno != EINTR) {
 357                                 warnmsg(LOG_ERR, __func__, "select: %s",
 358                                     strerror(errno));
 359                         }
 360                         continue;
 361                 }
 362
 363                 /* packet reception */
 364 #ifdef HAVE_POLL_H
 365                 if (set[1].revents & POLLIN)
 366 #else
 367                 if (FD_ISSET(rtsock, selectfdp))
 368 #endif
 369                         rtsock_input(rtsock);
 370 #ifdef HAVE_POLL_H
 371                 if (set[0].revents & POLLIN)
 372 #else
 373                 if (FD_ISSET(s, selectfdp))
 374 #endif
 375                         rtsol_input(s);
 376         }
 377         /* NOTREACHED */
 378
 379         return (0);
 380 }
 381
 382 int
 383 ifconfig(char *ifname)
 384 {
 385         struct ifinfo *ifi;
 386         struct sockaddr_dl *sdl;
 387         int flags;
 388
 389         if ((sdl = if_nametosdl(ifname)) == NULL) {
 390                 warnmsg(LOG_ERR, __func__,
 391                     "failed to get link layer information for %s", ifname);
 392                 return (-1);
 393         }
 394         if (find_ifinfo(sdl->sdl_index)) {
 395                 warnmsg(LOG_ERR, __func__,
 396                     "interface %s was already configured", ifname);
 397                 free(sdl);
 398                 return (-1);
 399         }
 400
 401         if ((ifi = malloc(sizeof(*ifi))) == NULL) {
 402                 warnmsg(LOG_ERR, __func__, "memory allocation failed");
 403                 free(sdl);
 404                 return (-1);
 405         }
 406         memset(ifi, 0, sizeof(*ifi));
 407         ifi->sdl = sdl;
 408
 409         strlcpy(ifi->ifname, ifname, sizeof(ifi->ifname));
 410
 411         /* construct a router solicitation message */
 412         if (make_packet(ifi))
 413                 goto bad;
 414
 415         /* set link ID of this interface. */
 416 #ifdef HAVE_SCOPELIB
 417         if (inet_zoneid(AF_INET6, 2, ifname, &ifi->linkid))
 418                 goto bad;
 419 #else
 420         /* XXX: assume interface IDs as link IDs */
 421         ifi->linkid = ifi->sdl->sdl_index;
 422 #endif
 423
 424         /*
 425          * check if the interface is available.
 426          * also check if SIOCGIFMEDIA ioctl is OK on the interface.
 427          */
 428         ifi->mediareqok = 1;
 429         ifi->active = interface_status(ifi);
 430         if (!ifi->mediareqok) {
 431                 /*
 432                  * probe routers periodically even if the link status
 433                  * does not change.
 434                  */
 435                 ifi->probeinterval = PROBE_INTERVAL;
 436         }
 437
 438         /* activate interface: interface_up returns 0 on success */
 439         flags = interface_up(ifi->ifname);
 440         if (flags == 0)
 441                 ifi->state = IFS_DELAY;
 442         else if (flags == IFS_TENTATIVE)
 443                 ifi->state = IFS_TENTATIVE;
 444         else
 445                 ifi->state = IFS_DOWN;
 446
 447         rtsol_timer_update(ifi);
 448
 449         TAILQ_INSERT_TAIL(&ifinfo_head, ifi, ifi_next);
 450         return (0);
 451
 452 bad:
 453         free(ifi->sdl);
 454         free(ifi);
 455         return (-1);
 456 }
 457
 458 void
 459 iflist_init(void)
 460 {
 461         struct ifinfo *ifi;
 462
 463         while ((ifi = TAILQ_FIRST(&ifinfo_head)) != NULL) {
 464                 TAILQ_REMOVE(&ifinfo_head, ifi, ifi_next);
 465                 if (ifi->sdl != NULL)
 466                         free(ifi->sdl);
 467                 if (ifi->rs_data != NULL)
 468                         free(ifi->rs_data);
 469                 free(ifi);
 470         }
 471 }
 472
 473 #if 0
 474 static int
 475 ifreconfig(char *ifname)
 476 {
 477         struct ifinfo *ifi, *prev;
 478         int rv;
 479
 480         prev = NULL;
 481         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 482                 if (strncmp(ifi->ifname, ifname, sizeof(ifi->ifname)) == 0)
 483                         break;
 484                 prev = ifi;
 485         }
 486         prev->next = ifi->next;
 487
 488         rv = ifconfig(ifname);
 489
 490         /* reclaim it after ifconfig() in case ifname is pointer inside ifi */
 491         if (ifi->rs_data)
 492                 free(ifi->rs_data);
 493         free(ifi->sdl);
 494         free(ifi);
 495
 496         return (rv);
 497 }
 498 #endif
 499
 500 struct ifinfo *
 501 find_ifinfo(int ifindex)
 502 {
 503         struct ifinfo *ifi;
 504
 505         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 506                 if (ifi->sdl->sdl_index == ifindex)
 507                         return (ifi);
 508         }
 509         return (NULL);
 510 }
 511
 512 static int
 513 make_packet(struct ifinfo *ifi)
 514 {
 515         size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
 516         struct nd_router_solicit *rs;
 517         char *buf;
 518
 519         if ((lladdroptlen = lladdropt_length(ifi->sdl)) == 0) {
 520                 warnmsg(LOG_INFO, __func__,
 521                     "link-layer address option has null length"
 522                     " on %s. Treat as not included.", ifi->ifname);
 523         }
 524         packlen += lladdroptlen;
 525         ifi->rs_datalen = packlen;
 526
 527         /* allocate buffer */
 528         if ((buf = malloc(packlen)) == NULL) {
 529                 warnmsg(LOG_ERR, __func__,
 530                     "memory allocation failed for %s", ifi->ifname);
 531                 return (-1);
 532         }
 533         ifi->rs_data = buf;
 534
 535         /* fill in the message */
 536         rs = (struct nd_router_solicit *)buf;
 537         rs->nd_rs_type = ND_ROUTER_SOLICIT;
 538         rs->nd_rs_code = 0;
 539         rs->nd_rs_cksum = 0;
 540         rs->nd_rs_reserved = 0;
 541         buf += sizeof(*rs);
 542
 543         /* fill in source link-layer address option */
 544         if (lladdroptlen)
 545                 lladdropt_fill(ifi->sdl, (struct nd_opt_hdr *)buf);
 546
 547         return (0);
 548 }
 549
 550 static struct timeval *
 551 rtsol_check_timer(void)
 552 {
 553         static struct timeval returnval;
 554         struct timeval now, rtsol_timer;
 555         struct ifinfo *ifi;
 556         struct ra_opt *rao;
 557         int flags;
 558
 559         gettimeofday(&now, NULL);
 560
 561         rtsol_timer = tm_max;
 562
 563         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 564                 if (timercmp(&ifi->expire, &now, <=)) {
 565                         if (dflag > 1)
 566                                 warnmsg(LOG_DEBUG, __func__,
 567                                     "timer expiration on %s, "
 568                                     "state = %d", ifi->ifname,
 569                                     ifi->state);
 570
 571                         /* Remove all RA options. */
 572                         while ((rao = TAILQ_FIRST(&ifi->ifi_ra_opt)) != NULL) {
 573                                 if (rao->rao_msg != NULL)
 574                                         free(rao->rao_msg);
 575                                 TAILQ_REMOVE(&ifi->ifi_ra_opt, rao, rao_next);
 576                                 free(rao);
 577                         }
 578                         switch (ifi->state) {
 579                         case IFS_DOWN:
 580                         case IFS_TENTATIVE:
 581                                 /* interface_up returns 0 on success */
 582                                 flags = interface_up(ifi->ifname);
 583                                 if (flags == 0)
 584                                         ifi->state = IFS_DELAY;
 585                                 else if (flags == IFS_TENTATIVE)
 586                                         ifi->state = IFS_TENTATIVE;
 587                                 else
 588                                         ifi->state = IFS_DOWN;
 589                                 break;
 590                         case IFS_IDLE:
 591                         {
 592                                 int oldstatus = ifi->active;
 593                                 int probe = 0;
 594
 595                                 ifi->active = interface_status(ifi);
 596
 597                                 if (oldstatus != ifi->active) {
 598                                         warnmsg(LOG_DEBUG, __func__,
 599                                             "%s status is changed"
 600                                             " from %d to %d",
 601                                             ifi->ifname,
 602                                             oldstatus, ifi->active);
 603                                         probe = 1;
 604                                         ifi->state = IFS_DELAY;
 605                                 } else if (ifi->probeinterval &&
 606                                     (ifi->probetimer -=
 607                                     ifi->timer.tv_sec) <= 0) {
 608                                         /* probe timer expired */
 609                                         ifi->probetimer =
 610                                             ifi->probeinterval;
 611                                         probe = 1;
 612                                         ifi->state = IFS_PROBE;
 613                                 }
 614
 615                                 /*
 616                                  * If we need a probe, clear the previous
 617                                  * status wrt the "other" configuration.
 618                                  */
 619                                 if (probe)
 620                                         ifi->otherconfig = 0;
 621
 622                                 if (probe && mobile_node)
 623                                         defrouter_probe(ifi);
 624                                 break;
 625                         }
 626                         case IFS_DELAY:
 627                                 ifi->state = IFS_PROBE;
 628                                 sendpacket(ifi);
 629                                 break;
 630                         case IFS_PROBE:
 631                                 if (ifi->probes < MAX_RTR_SOLICITATIONS)
 632                                         sendpacket(ifi);
 633                                 else {
 634                                         warnmsg(LOG_INFO, __func__,
 635                                             "No answer after sending %d RSs",
 636                                             ifi->probes);
 637                                         ifi->probes = 0;
 638                                         ifi->state = IFS_IDLE;
 639                                 }
 640                                 break;
 641                         }
 642                         rtsol_timer_update(ifi);
 643                 } else {
 644                         /* Expiration check for RA options. */
 645                         struct ra_opt *rao_tmp;
 646                         int expire = 0;
 647
 648                         TAILQ_FOREACH_SAFE(rao, &ifi->ifi_ra_opt, rao_next, rao_tmp) {
 649                                 warnmsg(LOG_DEBUG, __func__,
 650                                         "RA expiration timer: "
 651                                         "type=%d, msg=%s, timer=%ld:%08ld",
 652                                         rao->rao_type, (char *)rao->rao_msg,
 653                                         (long)rao->rao_expire.tv_sec,
 654                                         (long)rao->rao_expire.tv_usec);
 655                                 if (timercmp(&now, &rao->rao_expire, >=)) {
 656                                         warnmsg(LOG_DEBUG, __func__,
 657                                                 "RA expiration timer: expired.");
 658                                         TAILQ_REMOVE(&ifi->ifi_ra_opt, rao, rao_next);
 659                                         expire = 1;
 660                                 }
 661                         }
 662                         if (expire)
 663                                 ra_opt_handler(ifi);
 664                 }
 665                 if (timercmp(&ifi->expire, &rtsol_timer, <))
 666                         rtsol_timer = ifi->expire;
 667         }
 668
 669         if (timercmp(&rtsol_timer, &tm_max, ==)) {
 670                 warnmsg(LOG_DEBUG, __func__, "there is no timer");
 671                 return (NULL);
 672         } else if (timercmp(&rtsol_timer, &now, <))
 673                 /* this may occur when the interval is too small */
 674                 returnval.tv_sec = returnval.tv_usec = 0;
 675         else
 676                 timersub(&rtsol_timer, &now, &returnval);
 677
 678         if (dflag > 1)
 679                 warnmsg(LOG_DEBUG, __func__, "New timer is %ld:%08ld",
 680                     (long)returnval.tv_sec, (long)returnval.tv_usec);
 681
 682         return (&returnval);
 683 }
 684
 685 void
 686 rtsol_timer_update(struct ifinfo *ifi)
 687 {
 688 #define MILLION 1000000
 689 #define DADRETRY 10             /* XXX: adhoc */
 690         long interval;
 691         struct timeval now;
 692
 693         bzero(&ifi->timer, sizeof(ifi->timer));
 694
 695         switch (ifi->state) {
 696         case IFS_DOWN:
 697         case IFS_TENTATIVE:
 698                 if (++ifi->dadcount > DADRETRY) {
 699                         ifi->dadcount = 0;
 700                         ifi->timer.tv_sec = PROBE_INTERVAL;
 701                 } else
 702                         ifi->timer.tv_sec = 1;
 703                 break;
 704         case IFS_IDLE:
 705                 if (mobile_node) {
 706                         /* XXX should be configurable */
 707                         ifi->timer.tv_sec = 3;
 708                 }
 709                 else
 710                         ifi->timer = tm_max;    /* stop timer(valid?) */
 711                 break;
 712         case IFS_DELAY:
 713 #ifndef HAVE_ARC4RANDOM
 714                 interval = random() % (MAX_RTR_SOLICITATION_DELAY * MILLION);
 715 #else
 716                 interval = arc4random_uniform(MAX_RTR_SOLICITATION_DELAY * MILLION);
 717 #endif
 718                 ifi->timer.tv_sec = interval / MILLION;
 719                 ifi->timer.tv_usec = interval % MILLION;
 720                 break;
 721         case IFS_PROBE:
 722                 if (ifi->probes < MAX_RTR_SOLICITATIONS)
 723                         ifi->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
 724                 else {
 725                         /*
 726                          * After sending MAX_RTR_SOLICITATIONS solicitations,
 727                          * we're just waiting for possible replies; there
 728                          * will be no more solicitation.  Thus, we change
 729                          * the timer value to MAX_RTR_SOLICITATION_DELAY based
 730                          * on RFC 2461, Section 6.3.7.
 731                          */
 732                         ifi->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
 733                 }
 734                 break;
 735         default:
 736                 warnmsg(LOG_ERR, __func__,
 737                     "illegal interface state(%d) on %s",
 738                     ifi->state, ifi->ifname);
 739                 return;
 740         }
 741
 742         /* reset the timer */
 743         if (timercmp(&ifi->timer, &tm_max, ==)) {
 744                 ifi->expire = tm_max;
 745                 warnmsg(LOG_DEBUG, __func__,
 746                     "stop timer for %s", ifi->ifname);
 747         } else {
 748                 gettimeofday(&now, NULL);
 749                 timeradd(&now, &ifi->timer, &ifi->expire);
 750
 751                 if (dflag > 1)
 752                         warnmsg(LOG_DEBUG, __func__,
 753                             "set timer for %s to %d:%d", ifi->ifname,
 754                             (int)ifi->timer.tv_sec,
 755                             (int)ifi->timer.tv_usec);
 756         }
 757
 758 #undef MILLION
 759 }
 760
 761 /* timer related utility functions */
 762 #define MILLION 1000000
 763
 764 #ifndef SMALL
 765 static void
 766 rtsold_set_dump_file(int sig __unused)
 767 {
 768         do_dump = 1;
 769 }
 770 #endif
 771
 772 static void
 773 usage(void)
 774 {
 775 #ifndef SMALL
 776         fprintf(stderr, "usage: rtsold [-adDfFm1] [-O script-name] "
 777             "[-P pidfile] [-R script-name] interfaces...\n");
 778         fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
 779             "[-P pidfile] [-R script-name] -a\n");
 780 #else
 781         fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
 782             "[-P pidfile] [-R script-name] interfaces...\n");
 783         fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
 784             "[-P pidfile] [-R script-name] -a\n");
 785 #endif
 786 }
 787
 788 void
 789 warnmsg(int priority, const char *func, const char *msg, ...)
 790 {
 791         va_list ap;
 792         char buf[BUFSIZ];
 793
 794         va_start(ap, msg);
 795         if (fflag) {
 796                 if (priority <= log_upto) {
 797                         (void)vfprintf(stderr, msg, ap);
 798                         (void)fprintf(stderr, "\n");
 799                 }
 800         } else {
 801                 snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
 802                 msg = buf;
 803                 vsyslog(priority, msg, ap);
 804         }
 805         va_end(ap);
 806 }
 807
 808 /*
 809  * return a list of interfaces which is suitable to sending an RS.
 810  */
 811 char **
 812 autoifprobe(void)
 813 {
 814         static char **argv = NULL;
 815         static int n = 0;
 816         char **a;
 817         int s = 0, i, found;
 818         struct ifaddrs *ifap, *ifa, *target;
 819         struct in6_ndireq nd;
 820
 821         /* initialize */
 822         while (n--)
 823                 free(argv[n]);
 824         if (argv) {
 825                 free(argv);
 826                 argv = NULL;
 827         }
 828         n = 0;
 829
 830         if (getifaddrs(&ifap) != 0)
 831                 return (NULL);
 832
 833         if (!Fflag && (s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
 834                 warnmsg(LOG_ERR, __func__, "socket");
 835                 exit(1);
 836         }
 837
 838         target = NULL;
 839         /* find an ethernet */
 840         for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 841                 if ((ifa->ifa_flags & IFF_UP) == 0)
 842                         continue;
 843                 if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
 844                         continue;
 845                 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
 846                         continue;
 847                 if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
 848                         continue;
 849
 850                 if (ifa->ifa_addr->sa_family != AF_INET6)
 851                         continue;
 852
 853                 found = 0;
 854                 for (i = 0; i < n; i++) {
 855                         if (strcmp(argv[i], ifa->ifa_name) == 0) {
 856                                 found++;
 857                                 break;
 858                         }
 859                 }
 860                 if (found)
 861                         continue;
 862
 863                 /*
 864                  * Skip the interfaces which IPv6 and/or accepting RA
 865                  * is disabled.
 866                  */
 867                 if (!Fflag) {
 868                         memset(&nd, 0, sizeof(nd));
 869                         strlcpy(nd.ifname, ifa->ifa_name, sizeof(nd.ifname));
 870                         if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
 871                                 warnmsg(LOG_ERR, __func__,
 872                                         "ioctl(SIOCGIFINFO_IN6)");
 873                                 exit(1);
 874                         }
 875                         if ((nd.ndi.flags & ND6_IFF_IFDISABLED))
 876                                 continue;
 877                         if (!(nd.ndi.flags & ND6_IFF_ACCEPT_RTADV))
 878                                 continue;
 879                 }
 880
 881                 /* if we find multiple candidates, just warn. */
 882                 if (n != 0 && dflag > 1)
 883                         warnmsg(LOG_WARNING, __func__,
 884                                 "multiple interfaces found");
 885
 886                 a = (char **)realloc(argv, (n + 1) * sizeof(char **));
 887                 if (a == NULL) {
 888                         warnmsg(LOG_ERR, __func__, "realloc");
 889                         exit(1);
 890                 }
 891                 argv = a;
 892                 argv[n] = strdup(ifa->ifa_name);
 893                 if (!argv[n]) {
 894                         warnmsg(LOG_ERR, __func__, "malloc");
 895                         exit(1);
 896                 }
 897                 n++;
 898         }
 899
 900         if (n) {
 901                 a = (char **)realloc(argv, (n + 1) * sizeof(char **));
 902                 if (a == NULL) {
 903                         warnmsg(LOG_ERR, __func__, "realloc");
 904                         exit(1);
 905                 }
 906                 argv = a;
 907                 argv[n] = NULL;
 908
 909                 if (dflag > 0) {
 910                         for (i = 0; i < n; i++)
 911                                 warnmsg(LOG_WARNING, __func__, "probing %s",
 912                                         argv[i]);
 913                 }
 914         }
 915         if (!Fflag)
 916                 close(s);
 917         freeifaddrs(ifap);
 918         return (argv);
 919 }