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/time.h>
  36 #include <sys/socket.h>
  37 #include <sys/param.h>
  38
  39 #include <net/if.h>
  40 #include <net/if_dl.h>
  41
  42 #include <netinet/in.h>
  43 #include <netinet/icmp6.h>
  44
  45 #include <signal.h>
  46 #include <unistd.h>
  47 #include <syslog.h>
  48 #include <string.h>
  49 #include <stdlib.h>
  50 #include <stdio.h>
  51 #include <errno.h>
  52 #include <err.h>
  53 #include <stdarg.h>
  54 #include <ifaddrs.h>
  55 #ifdef HAVE_POLL_H
  56 #include <poll.h>
  57 #endif
  58
  59 #include "rtsold.h"
  60
  61 struct ifinfo *iflist;
  62 struct timeval tm_max = {0x7fffffff, 0x7fffffff};
  63 static int log_upto = 999;
  64 static int fflag = 0;
  65 static int Fflag = 0;   /* force setting sysctl parameters */
  66
  67 int aflag = 0;
  68 int dflag = 0;
  69
  70 char *otherconf_script;
  71
  72 /* protocol constants */
  73 #define MAX_RTR_SOLICITATION_DELAY      1 /* second */
  74 #define RTR_SOLICITATION_INTERVAL       4 /* seconds */
  75 #define MAX_RTR_SOLICITATIONS           3 /* times */
  76
  77 /*
  78  * implementation dependent constants in seconds
  79  * XXX: should be configurable
  80  */
  81 #define PROBE_INTERVAL 60
  82
  83 int main(int, char **);
  84
  85 /* static variables and functions */
  86 static int mobile_node = 0;
  87 #ifndef SMALL
  88 static int do_dump;
  89 static char *dumpfilename = "/var/run/rtsold.dump"; /* XXX: should be configurable */
  90 #endif
  91 #if 1
  92 static char *pidfilename = "/var/run/rtsold.pid"; /* should be configurable */
  93 #endif
  94
  95 #if 0
  96 static int ifreconfig(char *);
  97 #endif
  98 static int make_packet(struct ifinfo *);
  99 static struct timeval *rtsol_check_timer(void);
 100
 101 #ifndef SMALL
 102 static void rtsold_set_dump_file(int);
 103 #endif
 104 static void usage(char *);
 105
 106 int
 107 main(int argc, char **argv)
 108 {
 109         int s, ch, once = 0;
 110         struct timeval *timeout;
 111         char *argv0, *opts;
 112 #ifdef HAVE_POLL_H
 113         struct pollfd set[2];
 114 #else
 115         fd_set *fdsetp, *selectfdp;
 116         int fdmasks;
 117         int maxfd;
 118 #endif
 119         int rtsock;
 120
 121         /*
 122          * Initialization
 123          */
 124         argv0 = argv[0];
 125
 126         /* get option */
 127         if (argv0 && argv0[strlen(argv0) - 1] != 'd') {
 128                 fflag = 1;
 129                 once = 1;
 130                 opts = "adDFO:";
 131         } else
 132                 opts = "adDfFm1O:";
 133
 134         while ((ch = getopt(argc, argv, opts)) != -1) {
 135                 switch (ch) {
 136                 case 'a':
 137                         aflag = 1;
 138                         break;
 139                 case 'd':
 140                         dflag = 1;
 141                         break;
 142                 case 'D':
 143                         dflag = 2;
 144                         break;
 145                 case 'f':
 146                         fflag = 1;
 147                         break;
 148                 case 'F':
 149                         Fflag = 1;
 150                         break;
 151                 case 'm':
 152                         mobile_node = 1;
 153                         break;
 154                 case '1':
 155                         once = 1;
 156                         break;
 157                 case 'O':
 158                         otherconf_script = optarg;
 159                         break;
 160                 default:
 161                         usage(argv0);
 162                         /*NOTREACHED*/
 163                 }
 164         }
 165         argc -= optind;
 166         argv += optind;
 167
 168         if ((!aflag && argc == 0) || (aflag && argc != 0)) {
 169                 usage(argv0);
 170                 /*NOTREACHED*/
 171         }
 172
 173         /* set log level */
 174         if (dflag == 0)
 175                 log_upto = LOG_NOTICE;
 176         if (!fflag) {
 177                 char *ident;
 178
 179                 ident = strrchr(argv0, '/');
 180                 if (!ident)
 181                         ident = argv0;
 182                 else
 183                         ident++;
 184                 openlog(ident, LOG_NDELAY|LOG_PID, LOG_DAEMON);
 185                 if (log_upto >= 0)
 186                         setlogmask(LOG_UPTO(log_upto));
 187         }
 188
 189         if (otherconf_script && *otherconf_script != '/') {
 190                 errx(1, "configuration script (%s) must be an absolute path",
 191                     otherconf_script);
 192         }
 193
 194 #ifndef HAVE_ARC4RANDOM
 195         /* random value initialization */
 196         srandom((u_long)time(NULL));
 197 #endif
 198
 199         if (Fflag) {
 200                 setinet6sysctl(IPV6CTL_ACCEPT_RTADV, 1);
 201                 setinet6sysctl(IPV6CTL_FORWARDING, 0);
 202         } else {
 203                 /* warn if accept_rtadv is down */
 204                 if (!getinet6sysctl(IPV6CTL_ACCEPT_RTADV))
 205                         warnx("kernel is configured not to accept RAs");
 206                 /* warn if forwarding is up */
 207                 if (getinet6sysctl(IPV6CTL_FORWARDING))
 208                         warnx("kernel is configured as a router, not a host");
 209         }
 210
 211 #ifndef SMALL
 212         /* initialization to dump internal status to a file */
 213         signal(SIGUSR1, rtsold_set_dump_file);
 214 #endif
 215
 216         if (!fflag)
 217                 daemon(0, 0);           /* act as a daemon */
 218
 219         /*
 220          * Open a socket for sending RS and receiving RA.
 221          * This should be done before calling ifinit(), since the function
 222          * uses the socket.
 223          */
 224         if ((s = sockopen()) < 0) {
 225                 warnmsg(LOG_ERR, __func__, "failed to open a socket");
 226                 exit(1);
 227                 /*NOTREACHED*/
 228         }
 229 #ifdef HAVE_POLL_H
 230         set[0].fd = s;
 231         set[0].events = POLLIN;
 232 #else
 233         maxfd = s;
 234 #endif
 235
 236 #ifdef HAVE_POLL_H
 237         set[1].fd = -1;
 238 #endif
 239
 240         if ((rtsock = rtsock_open()) < 0) {
 241                 warnmsg(LOG_ERR, __func__, "failed to open a socket");
 242                 exit(1);
 243                 /*NOTREACHED*/
 244         }
 245 #ifdef HAVE_POLL_H
 246         set[1].fd = rtsock;
 247         set[1].events = POLLIN;
 248 #else
 249         if (rtsock > maxfd)
 250                 maxfd = rtsock;
 251 #endif
 252
 253 #ifndef HAVE_POLL_H
 254         fdmasks = howmany(maxfd + 1, NFDBITS) * sizeof(fd_mask);
 255         if ((fdsetp = malloc(fdmasks)) == NULL) {
 256                 err(1, "malloc");
 257                 /*NOTREACHED*/
 258         }
 259         if ((selectfdp = malloc(fdmasks)) == NULL) {
 260                 err(1, "malloc");
 261                 /*NOTREACHED*/
 262         }
 263 #endif
 264
 265         /* configuration per interface */
 266         if (ifinit()) {
 267                 warnmsg(LOG_ERR, __func__,
 268                     "failed to initialize interfaces");
 269                 exit(1);
 270                 /*NOTREACHED*/
 271         }
 272         if (aflag)
 273                 argv = autoifprobe();
 274         while (argv && *argv) {
 275                 if (ifconfig(*argv)) {
 276                         warnmsg(LOG_ERR, __func__,
 277                             "failed to initialize %s", *argv);
 278                         exit(1);
 279                         /*NOTREACHED*/
 280                 }
 281                 argv++;
 282         }
 283
 284         /* setup for probing default routers */
 285         if (probe_init()) {
 286                 warnmsg(LOG_ERR, __func__,
 287                     "failed to setup for probing routers");
 288                 exit(1);
 289                 /*NOTREACHED*/
 290         }
 291
 292 #if 1
 293         /* dump the current pid */
 294         if (!once) {
 295                 pid_t pid = getpid();
 296                 FILE *fp;
 297
 298                 if ((fp = fopen(pidfilename, "w")) == NULL)
 299                         warnmsg(LOG_ERR, __func__,
 300                             "failed to open a pid log file(%s): %s",
 301                             pidfilename, strerror(errno));
 302                 else {
 303                         fprintf(fp, "%d\n", pid);
 304                         fclose(fp);
 305                 }
 306         }
 307 #endif
 308
 309 #ifndef HAVE_POLL_H
 310         memset(fdsetp, 0, fdmasks);
 311         FD_SET(s, fdsetp);
 312         FD_SET(rtsock, fdsetp);
 313 #endif
 314         while (1) {             /* main loop */
 315                 int e;
 316
 317 #ifndef HAVE_POLL_H
 318                 memcpy(selectfdp, fdsetp, fdmasks);
 319 #endif
 320
 321 #ifndef SMALL
 322                 if (do_dump) {  /* SIGUSR1 */
 323                         do_dump = 0;
 324                         rtsold_dump_file(dumpfilename);
 325                 }
 326 #endif
 327
 328                 timeout = rtsol_check_timer();
 329
 330                 if (once) {
 331                         struct ifinfo *ifi;
 332
 333                         /* if we have no timeout, we are done (or failed) */
 334                         if (timeout == NULL)
 335                                 break;
 336
 337                         /* if all interfaces have got RA packet, we are done */
 338                         for (ifi = iflist; ifi; ifi = ifi->next) {
 339                                 if (ifi->state != IFS_DOWN && ifi->racnt == 0)
 340                                         break;
 341                         }
 342                         if (ifi == NULL)
 343                                 break;
 344                 }
 345 #ifdef HAVE_POLL_H
 346                 e = poll(set, 2, timeout ? (timeout->tv_sec * 1000 + timeout->tv_usec / 1000) : INFTIM);
 347 #else
 348                 e = select(maxfd + 1, selectfdp, NULL, NULL, timeout);
 349 #endif
 350                 if (e < 1) {
 351                         if (e < 0 && errno != EINTR) {
 352                                 warnmsg(LOG_ERR, __func__, "select: %s",
 353                                     strerror(errno));
 354                         }
 355                         continue;
 356                 }
 357
 358                 /* packet reception */
 359 #ifdef HAVE_POLL_H
 360                 if (set[1].revents & POLLIN)
 361 #else
 362                 if (FD_ISSET(rtsock, selectfdp))
 363 #endif
 364                         rtsock_input(rtsock);
 365 #ifdef HAVE_POLL_H
 366                 if (set[0].revents & POLLIN)
 367 #else
 368                 if (FD_ISSET(s, selectfdp))
 369 #endif
 370                         rtsol_input(s);
 371         }
 372         /* NOTREACHED */
 373
 374         return 0;
 375 }
 376
 377 int
 378 ifconfig(char *ifname)
 379 {
 380         struct ifinfo *ifinfo;
 381         struct sockaddr_dl *sdl;
 382         int flags;
 383
 384         if ((sdl = if_nametosdl(ifname)) == NULL) {
 385                 warnmsg(LOG_ERR, __func__,
 386                     "failed to get link layer information for %s", ifname);
 387                 return(-1);
 388         }
 389         if (find_ifinfo(sdl->sdl_index)) {
 390                 warnmsg(LOG_ERR, __func__,
 391                     "interface %s was already configured", ifname);
 392                 free(sdl);
 393                 return(-1);
 394         }
 395
 396         if ((ifinfo = malloc(sizeof(*ifinfo))) == NULL) {
 397                 warnmsg(LOG_ERR, __func__, "memory allocation failed");
 398                 free(sdl);
 399                 return(-1);
 400         }
 401         memset(ifinfo, 0, sizeof(*ifinfo));
 402         ifinfo->sdl = sdl;
 403
 404         strlcpy(ifinfo->ifname, ifname, sizeof(ifinfo->ifname));
 405
 406         /* construct a router solicitation message */
 407         if (make_packet(ifinfo))
 408                 goto bad;
 409
 410         /* set link ID of this interface. */
 411 #ifdef HAVE_SCOPELIB
 412         if (inet_zoneid(AF_INET6, 2, ifname, &ifinfo->linkid))
 413                 goto bad;
 414 #else
 415         /* XXX: assume interface IDs as link IDs */
 416         ifinfo->linkid = ifinfo->sdl->sdl_index;
 417 #endif
 418
 419         /*
 420          * check if the interface is available.
 421          * also check if SIOCGIFMEDIA ioctl is OK on the interface.
 422          */
 423         ifinfo->mediareqok = 1;
 424         ifinfo->active = interface_status(ifinfo);
 425         if (!ifinfo->mediareqok) {
 426                 /*
 427                  * probe routers periodically even if the link status
 428                  * does not change.
 429                  */
 430                 ifinfo->probeinterval = PROBE_INTERVAL;
 431         }
 432
 433         /* activate interface: interface_up returns 0 on success */
 434         flags = interface_up(ifinfo->ifname);
 435         if (flags == 0)
 436                 ifinfo->state = IFS_DELAY;
 437         else if (flags == IFS_TENTATIVE)
 438                 ifinfo->state = IFS_TENTATIVE;
 439         else
 440                 ifinfo->state = IFS_DOWN;
 441
 442         rtsol_timer_update(ifinfo);
 443
 444         /* link into chain */
 445         if (iflist)
 446                 ifinfo->next = iflist;
 447         iflist = ifinfo;
 448
 449         return(0);
 450
 451 bad:
 452         free(ifinfo->sdl);
 453         free(ifinfo);
 454         return(-1);
 455 }
 456
 457 void
 458 iflist_init(void)
 459 {
 460         struct ifinfo *ifi, *next;
 461
 462         for (ifi = iflist; ifi; ifi = next) {
 463                 next = ifi->next;
 464                 if (ifi->sdl)
 465                         free(ifi->sdl);
 466                 if (ifi->rs_data)
 467                         free(ifi->rs_data);
 468                 free(ifi);
 469                 iflist = NULL;
 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         for (ifi = iflist; ifi; ifi = 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         return rv;
 496 }
 497 #endif
 498
 499 struct ifinfo *
 500 find_ifinfo(int ifindex)
 501 {
 502         struct ifinfo *ifi;
 503
 504         for (ifi = iflist; ifi; ifi = ifi->next)
 505                 if (ifi->sdl->sdl_index == ifindex)
 506                         return(ifi);
 507         return(NULL);
 508 }
 509
 510 static int
 511 make_packet(struct ifinfo *ifinfo)
 512 {
 513         size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
 514         struct nd_router_solicit *rs;
 515         char *buf;
 516
 517         if ((lladdroptlen = lladdropt_length(ifinfo->sdl)) == 0) {
 518                 warnmsg(LOG_INFO, __func__,
 519                     "link-layer address option has null length"
 520                     " on %s. Treat as not included.", ifinfo->ifname);
 521         }
 522         packlen += lladdroptlen;
 523         ifinfo->rs_datalen = packlen;
 524
 525         /* allocate buffer */
 526         if ((buf = malloc(packlen)) == NULL) {
 527                 warnmsg(LOG_ERR, __func__,
 528                     "memory allocation failed for %s", ifinfo->ifname);
 529                 return(-1);
 530         }
 531         ifinfo->rs_data = buf;
 532
 533         /* fill in the message */
 534         rs = (struct nd_router_solicit *)buf;
 535         rs->nd_rs_type = ND_ROUTER_SOLICIT;
 536         rs->nd_rs_code = 0;
 537         rs->nd_rs_cksum = 0;
 538         rs->nd_rs_reserved = 0;
 539         buf += sizeof(*rs);
 540
 541         /* fill in source link-layer address option */
 542         if (lladdroptlen)
 543                 lladdropt_fill(ifinfo->sdl, (struct nd_opt_hdr *)buf);
 544
 545         return(0);
 546 }
 547
 548 static struct timeval *
 549 rtsol_check_timer(void)
 550 {
 551         static struct timeval returnval;
 552         struct timeval now, rtsol_timer;
 553         struct ifinfo *ifinfo;
 554         int flags;
 555
 556         gettimeofday(&now, NULL);
 557
 558         rtsol_timer = tm_max;
 559
 560         for (ifinfo = iflist; ifinfo; ifinfo = ifinfo->next) {
 561                 if (timercmp(&ifinfo->expire, &now, <=)) {
 562                         if (dflag > 1)
 563                                 warnmsg(LOG_DEBUG, __func__,
 564                                     "timer expiration on %s, "
 565                                     "state = %d", ifinfo->ifname,
 566                                     ifinfo->state);
 567
 568                         switch (ifinfo->state) {
 569                         case IFS_DOWN:
 570                         case IFS_TENTATIVE:
 571                                 /* interface_up returns 0 on success */
 572                                 flags = interface_up(ifinfo->ifname);
 573                                 if (flags == 0)
 574                                         ifinfo->state = IFS_DELAY;
 575                                 else if (flags == IFS_TENTATIVE)
 576                                         ifinfo->state = IFS_TENTATIVE;
 577                                 else
 578                                         ifinfo->state = IFS_DOWN;
 579                                 break;
 580                         case IFS_IDLE:
 581                         {
 582                                 int oldstatus = ifinfo->active;
 583                                 int probe = 0;
 584
 585                                 ifinfo->active = interface_status(ifinfo);
 586
 587                                 if (oldstatus != ifinfo->active) {
 588                                         warnmsg(LOG_DEBUG, __func__,
 589                                             "%s status is changed"
 590                                             " from %d to %d",
 591                                             ifinfo->ifname,
 592                                             oldstatus, ifinfo->active);
 593                                         probe = 1;
 594                                         ifinfo->state = IFS_DELAY;
 595                                 } else if (ifinfo->probeinterval &&
 596                                     (ifinfo->probetimer -=
 597                                     ifinfo->timer.tv_sec) <= 0) {
 598                                         /* probe timer expired */
 599                                         ifinfo->probetimer =
 600                                             ifinfo->probeinterval;
 601                                         probe = 1;
 602                                         ifinfo->state = IFS_PROBE;
 603                                 }
 604
 605                                 /*
 606                                  * If we need a probe, clear the previous
 607                                  * status wrt the "other" configuration.
 608                                  */
 609                                 if (probe)
 610                                         ifinfo->otherconfig = 0;
 611
 612                                 if (probe && mobile_node)
 613                                         defrouter_probe(ifinfo);
 614                                 break;
 615                         }
 616                         case IFS_DELAY:
 617                                 ifinfo->state = IFS_PROBE;
 618                                 sendpacket(ifinfo);
 619                                 break;
 620                         case IFS_PROBE:
 621                                 if (ifinfo->probes < MAX_RTR_SOLICITATIONS)
 622                                         sendpacket(ifinfo);
 623                                 else {
 624                                         warnmsg(LOG_INFO, __func__,
 625                                             "No answer after sending %d RSs",
 626                                             ifinfo->probes);
 627                                         ifinfo->probes = 0;
 628                                         ifinfo->state = IFS_IDLE;
 629                                 }
 630                                 break;
 631                         }
 632                         rtsol_timer_update(ifinfo);
 633                 }
 634
 635                 if (timercmp(&ifinfo->expire, &rtsol_timer, <))
 636                         rtsol_timer = ifinfo->expire;
 637         }
 638
 639         if (timercmp(&rtsol_timer, &tm_max, ==)) {
 640                 warnmsg(LOG_DEBUG, __func__, "there is no timer");
 641                 return(NULL);
 642         } else if (timercmp(&rtsol_timer, &now, <))
 643                 /* this may occur when the interval is too small */
 644                 returnval.tv_sec = returnval.tv_usec = 0;
 645         else
 646                 timersub(&rtsol_timer, &now, &returnval);
 647
 648         if (dflag > 1)
 649                 warnmsg(LOG_DEBUG, __func__, "New timer is %ld:%08ld",
 650                     (long)returnval.tv_sec, (long)returnval.tv_usec);
 651
 652         return(&returnval);
 653 }
 654
 655 void
 656 rtsol_timer_update(struct ifinfo *ifinfo)
 657 {
 658 #define MILLION 1000000
 659 #define DADRETRY 10             /* XXX: adhoc */
 660         long interval;
 661         struct timeval now;
 662
 663         bzero(&ifinfo->timer, sizeof(ifinfo->timer));
 664
 665         switch (ifinfo->state) {
 666         case IFS_DOWN:
 667         case IFS_TENTATIVE:
 668                 if (++ifinfo->dadcount > DADRETRY) {
 669                         ifinfo->dadcount = 0;
 670                         ifinfo->timer.tv_sec = PROBE_INTERVAL;
 671                 } else
 672                         ifinfo->timer.tv_sec = 1;
 673                 break;
 674         case IFS_IDLE:
 675                 if (mobile_node) {
 676                         /* XXX should be configurable */
 677                         ifinfo->timer.tv_sec = 3;
 678                 }
 679                 else
 680                         ifinfo->timer = tm_max; /* stop timer(valid?) */
 681                 break;
 682         case IFS_DELAY:
 683 #ifndef HAVE_ARC4RANDOM
 684                 interval = random() % (MAX_RTR_SOLICITATION_DELAY * MILLION);
 685 #else
 686                 interval = arc4random_uniform(MAX_RTR_SOLICITATION_DELAY * MILLION);
 687 #endif
 688                 ifinfo->timer.tv_sec = interval / MILLION;
 689                 ifinfo->timer.tv_usec = interval % MILLION;
 690                 break;
 691         case IFS_PROBE:
 692                 if (ifinfo->probes < MAX_RTR_SOLICITATIONS)
 693                         ifinfo->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
 694                 else {
 695                         /*
 696                          * After sending MAX_RTR_SOLICITATIONS solicitations,
 697                          * we're just waiting for possible replies; there
 698                          * will be no more solicitation.  Thus, we change
 699                          * the timer value to MAX_RTR_SOLICITATION_DELAY based
 700                          * on RFC 2461, Section 6.3.7.
 701                          */
 702                         ifinfo->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
 703                 }
 704                 break;
 705         default:
 706                 warnmsg(LOG_ERR, __func__,
 707                     "illegal interface state(%d) on %s",
 708                     ifinfo->state, ifinfo->ifname);
 709                 return;
 710         }
 711
 712         /* reset the timer */
 713         if (timercmp(&ifinfo->timer, &tm_max, ==)) {
 714                 ifinfo->expire = tm_max;
 715                 warnmsg(LOG_DEBUG, __func__,
 716                     "stop timer for %s", ifinfo->ifname);
 717         } else {
 718                 gettimeofday(&now, NULL);
 719                 timeradd(&now, &ifinfo->timer, &ifinfo->expire);
 720
 721                 if (dflag > 1)
 722                         warnmsg(LOG_DEBUG, __func__,
 723                             "set timer for %s to %d:%d", ifinfo->ifname,
 724                             (int)ifinfo->timer.tv_sec,
 725                             (int)ifinfo->timer.tv_usec);
 726         }
 727
 728 #undef MILLION
 729 }
 730
 731 /* timer related utility functions */
 732 #define MILLION 1000000
 733
 734 #ifndef SMALL
 735 static void
 736 rtsold_set_dump_file(int sig)
 737 {
 738         do_dump = 1;
 739 }
 740 #endif
 741
 742 static void
 743 usage(char *progname)
 744 {
 745         if (progname && progname[strlen(progname) - 1] != 'd') {
 746                 fprintf(stderr, "usage: rtsol [-dDF] interfaces...\n");
 747                 fprintf(stderr, "usage: rtsol [-dDF] -a\n");
 748         } else {
 749                 fprintf(stderr, "usage: rtsold [-adDfFm1] interfaces...\n");
 750                 fprintf(stderr, "usage: rtsold [-dDfFm1] -a\n");
 751         }
 752         exit(1);
 753 }
 754
 755 void
 756 #if __STDC__
 757 warnmsg(int priority, const char *func, const char *msg, ...)
 758 #else
 759 warnmsg(priority, func, msg, va_alist)
 760         int priority;
 761         const char *func;
 762         const char *msg;
 763         va_dcl
 764 #endif
 765 {
 766         va_list ap;
 767         char buf[BUFSIZ];
 768
 769         va_start(ap, msg);
 770         if (fflag) {
 771                 if (priority <= log_upto) {
 772                         (void)vfprintf(stderr, msg, ap);
 773                         (void)fprintf(stderr, "\n");
 774                 }
 775         } else {
 776                 snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
 777                 msg = buf;
 778                 vsyslog(priority, msg, ap);
 779         }
 780         va_end(ap);
 781 }
 782
 783 /*
 784  * return a list of interfaces which is suitable to sending an RS.
 785  */
 786 char **
 787 autoifprobe(void)
 788 {
 789         static char **argv = NULL;
 790         static int n = 0;
 791         char **a;
 792         int i, found;
 793         struct ifaddrs *ifap, *ifa, *target;
 794
 795         /* initialize */
 796         while (n--)
 797                 free(argv[n]);
 798         if (argv) {
 799                 free(argv);
 800                 argv = NULL;
 801         }
 802         n = 0;
 803
 804         if (getifaddrs(&ifap) != 0)
 805                 return NULL;
 806
 807         target = NULL;
 808         /* find an ethernet */
 809         for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 810                 if ((ifa->ifa_flags & IFF_UP) == 0)
 811                         continue;
 812                 if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
 813                         continue;
 814                 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
 815                         continue;
 816                 if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
 817                         continue;
 818
 819                 if (ifa->ifa_addr->sa_family != AF_INET6)
 820                         continue;
 821
 822                 found = 0;
 823                 for (i = 0; i < n; i++) {
 824                         if (strcmp(argv[i], ifa->ifa_name) == 0) {
 825                                 found++;
 826                                 break;
 827                         }
 828                 }
 829                 if (found)
 830                         continue;
 831
 832                 /* if we find multiple candidates, just warn. */
 833                 if (n != 0 && dflag > 1)
 834                         warnx("multiple interfaces found");
 835
 836                 a = (char **)realloc(argv, (n + 1) * sizeof(char **));
 837                 if (a == NULL)
 838                         err(1, "realloc");
 839                 argv = a;
 840                 argv[n] = strdup(ifa->ifa_name);
 841                 if (!argv[n])
 842                         err(1, "malloc");
 843                 n++;
 844                 argv[n] = NULL;
 845         }
 846
 847         if (n) {
 848                 a = (char **)realloc(argv, (n + 1) * sizeof(char **));
 849                 if (a == NULL)
 850                         err(1, "realloc");
 851                 argv = a;
 852                 argv[n] = NULL;
 853
 854                 if (dflag > 0) {
 855                         for (i = 0; i < n; i++)
 856                                 warnx("probing %s", argv[i]);
 857                 }
 858         }
 859         freeifaddrs(ifap);
 860         return argv;
 861 }