usr.sbin/rtsold/rtsold.c

   1 /*      $KAME: rtsold.c,v 1.31 2001/05/22 06:03:06 jinmei 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/rtsold/rtsold.c,v 1.1.2.4 2002/04/04 11:07:19 ume Exp $
  32  */
  33
  34 #include <sys/types.h>
  35 #include <sys/time.h>
  36 #include <sys/socket.h>
  37
  38 #include <net/if.h>
  39 #include <net/if_dl.h>
  40
  41 #include <netinet/in.h>
  42 #include <netinet/icmp6.h>
  43
  44 #include <signal.h>
  45 #include <unistd.h>
  46 #include <syslog.h>
  47 #include <string.h>
  48 #include <stdlib.h>
  49 #include <stdio.h>
  50 #include <errno.h>
  51 #include <err.h>
  52 #include <stdarg.h>
  53 #include <ifaddrs.h>
  54 #include "rtsold.h"
  55
  56 struct ifinfo *iflist;
  57 struct timeval tm_max = {0x7fffffff, 0x7fffffff};
  58 int aflag = 0;
  59 int dflag = 0;
  60 static int log_upto = 999;
  61 static int fflag = 0;
  62
  63 /* protocol constatns */
  64 #define MAX_RTR_SOLICITATION_DELAY      1 /* second */
  65 #define RTR_SOLICITATION_INTERVAL       4 /* seconds */
  66 #define MAX_RTR_SOLICITATIONS           3 /* times */
  67
  68 /* implementation dependent constants */
  69 #define PROBE_INTERVAL 60       /* secondes XXX: should be configurable */
  70
  71 /* utility macros */
  72 /* a < b */
  73 #define TIMEVAL_LT(a, b) (((a).tv_sec < (b).tv_sec) ||\
  74                           (((a).tv_sec == (b).tv_sec) && \
  75                             ((a).tv_usec < (b).tv_usec)))
  76
  77 /* a <= b */
  78 #define TIMEVAL_LEQ(a, b) (((a).tv_sec < (b).tv_sec) ||\
  79                            (((a).tv_sec == (b).tv_sec) &&\
  80                             ((a).tv_usec <= (b).tv_usec)))
  81
  82 /* a == b */
  83 #define TIMEVAL_EQ(a, b) (((a).tv_sec==(b).tv_sec) && ((a).tv_usec==(b).tv_usec))
  84
  85 /* static variables and functions */
  86 static int mobile_node = 0;
  87 static int do_dump;
  88 /*
  89  * XXX: the following two values should be configurable
  90  */
  91 static const char *dumpfilename = "/var/run/rtsold.dump";
  92 static const char *pidfilename = "/var/run/rtsold.pid";
  93
  94 static int ifconfig(char *ifname);
  95 #if 0
  96 static int ifreconfig(char *ifname);
  97 #endif
  98 static int make_packet(struct ifinfo *ifinfo);
  99 static struct timeval *rtsol_check_timer(void);
 100 static void TIMEVAL_ADD(struct timeval *a, struct timeval *b,
 101                              struct timeval *result);
 102 static void TIMEVAL_SUB(struct timeval *a, struct timeval *b,
 103                              struct timeval *result);
 104
 105 static void rtsold_set_dump_file(int);
 106 static void usage(char *progname);
 107 static char **autoifprobe(void);
 108
 109 int
 110 main(int argc, char *argv[])
 111 {
 112         int s, rtsock, maxfd, ch;
 113         int once = 0;
 114         struct timeval *timeout;
 115         struct fd_set fdset;
 116         char *argv0;
 117         const char *opts;
 118
 119         /*
 120          * Initialization
 121          */
 122         argv0 = argv[0];
 123
 124         /* get option */
 125         if (argv0 && argv0[strlen(argv0) - 1] != 'd') {
 126                 fflag = 1;
 127                 once = 1;
 128                 opts = "adD";
 129         } else
 130                 opts = "adDfm1";
 131
 132         while ((ch = getopt(argc, argv, opts)) != -1) {
 133                 switch (ch) {
 134                 case 'a':
 135                         aflag = 1;
 136                         break;
 137                 case 'd':
 138                         dflag = 1;
 139                         break;
 140                 case 'D':
 141                         dflag = 2;
 142                         break;
 143                 case 'f':
 144                         fflag = 1;
 145                         break;
 146                 case 'm':
 147                         mobile_node = 1;
 148                         break;
 149                 case '1':
 150                         once = 1;
 151                         break;
 152                 default:
 153                         usage(argv0);
 154                         /*NOTREACHED*/
 155                 }
 156         }
 157         argc -= optind;
 158         argv += optind;
 159
 160         if (aflag) {
 161                 int i;
 162
 163                 if (argc != 0) {
 164                         usage(argv0);
 165                         /*NOTREACHED*/
 166                 }
 167
 168                 argv = autoifprobe();
 169                 if (!argv) {
 170                         errx(1, "could not autoprobe interface");
 171                         /*NOTREACHED*/
 172                 }
 173
 174                 for (i = 0; argv[i]; i++)
 175                         ;
 176                 argc = i;
 177         }
 178         if (argc == 0) {
 179                 usage(argv0);
 180                 /*NOTREACHED*/
 181         }
 182
 183         /* set log level */
 184         if (dflag == 0)
 185                 log_upto = LOG_NOTICE;
 186         if (!fflag) {
 187                 char *ident;
 188                 ident = strrchr(argv0, '/');
 189                 if (!ident)
 190                         ident = argv0;
 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 #ifndef HAVE_ARC4RANDOM
 199         /* random value initilization */
 200         srandom((u_long)time(NULL));
 201 #endif
 202
 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         /* initialization to dump internal status to a file */
 211         if (signal(SIGUSR1, rtsold_set_dump_file) == SIG_ERR) {
 212                 errx(1, "failed to set signal for dump status");
 213                 /*NOTREACHED*/
 214         }
 215
 216         /*
 217          * Open a socket for sending RS and receiving RA.
 218          * This should be done before calling ifinit(), since the function
 219          * uses the socket.
 220          */
 221         if ((s = sockopen()) < 0) {
 222                 errx(1, "failed to open a socket");
 223                 /*NOTREACHED*/
 224         }
 225         maxfd = s;
 226         if ((rtsock = rtsock_open()) < 0) {
 227                 errx(1, "failed to open a socket");
 228                 /*NOTREACHED*/
 229         }
 230         if (rtsock > maxfd)
 231                 maxfd = rtsock;
 232
 233         /* configuration per interface */
 234         if (ifinit()) {
 235                 errx(1, "failed to initilizatoin interfaces");
 236                 /*NOTREACHED*/
 237         }
 238         while (argc--) {
 239                 if (ifconfig(*argv)) {
 240                         errx(1, "failed to initialize %s", *argv);
 241                         /*NOTREACHED*/
 242                 }
 243                 argv++;
 244         }
 245
 246         /* setup for probing default routers */
 247         if (probe_init()) {
 248                 errx(1, "failed to setup for probing routers");
 249                 /*NOTREACHED*/
 250         }
 251
 252         if (!fflag)
 253                 daemon(0, 0);           /* act as a daemon */
 254
 255         /* dump the current pid */
 256         if (!once) {
 257                 pid_t pid = getpid();
 258                 FILE *fp;
 259
 260                 if ((fp = fopen(pidfilename, "w")) == NULL)
 261                         warnmsg(LOG_ERR, __func__,
 262                                 "failed to open a log file(%s): %s",
 263                                 pidfilename, strerror(errno));
 264                 else {
 265                         fprintf(fp, "%d\n", pid);
 266                         fclose(fp);
 267                 }
 268         }
 269
 270         FD_ZERO(&fdset);
 271         FD_SET(s, &fdset);
 272         FD_SET(rtsock, &fdset);
 273         while (1) {             /* main loop */
 274                 int e;
 275                 struct fd_set select_fd = fdset;
 276
 277                 if (do_dump) {  /* SIGUSR1 */
 278                         do_dump = 0;
 279                         rtsold_dump_file(dumpfilename);
 280                 }
 281
 282                 timeout = rtsol_check_timer();
 283
 284                 if (once) {
 285                         struct ifinfo *ifi;
 286
 287                         /* if we have no timeout, we are done (or failed) */
 288                         if (timeout == NULL)
 289                                 break;
 290
 291                         /* if all interfaces have got RA packet, we are done */
 292                         for (ifi = iflist; ifi; ifi = ifi->next) {
 293                                 if (ifi->state != IFS_DOWN && ifi->racnt == 0)
 294                                         break;
 295                         }
 296                         if (ifi == NULL)
 297                                 break;
 298                 }
 299                 e = select(maxfd + 1, &select_fd, NULL, NULL, timeout);
 300                 if (e < 1) {
 301                         if (e < 0 && errno != EINTR) {
 302                                 warnmsg(LOG_ERR, __func__, "select: %s",
 303                                        strerror(errno));
 304                         }
 305                         continue;
 306                 }
 307
 308                 /* packet reception */
 309                 if (FD_ISSET(rtsock, &select_fd))
 310                         rtsock_input(rtsock);
 311                 if (FD_ISSET(s, &select_fd))
 312                         rtsol_input(s);
 313         }
 314         /* NOTREACHED */
 315
 316         return 0;
 317 }
 318
 319 static int
 320 ifconfig(char *ifname)
 321 {
 322         struct ifinfo *ifinfo;
 323         struct sockaddr_dl *sdl;
 324         int flags;
 325
 326         if ((sdl = if_nametosdl(ifname)) == NULL) {
 327                 warnmsg(LOG_ERR, __func__,
 328                        "failed to get link layer information for %s", ifname);
 329                 return(-1);
 330         }
 331         if (find_ifinfo(sdl->sdl_index)) {
 332                 warnmsg(LOG_ERR, __func__,
 333                         "interface %s was already configured", ifname);
 334                 free(sdl);
 335                 return(-1);
 336         }
 337
 338         if ((ifinfo = malloc(sizeof(*ifinfo))) == NULL) {
 339                 warnmsg(LOG_ERR, __func__, "memory allocation failed");
 340                 free(sdl);
 341                 return(-1);
 342         }
 343         memset(ifinfo, 0, sizeof(*ifinfo));
 344         ifinfo->sdl = sdl;
 345
 346         strncpy(ifinfo->ifname, ifname, sizeof(ifinfo->ifname));
 347
 348         /* construct a router solicitation message */
 349         if (make_packet(ifinfo))
 350                 goto bad;
 351
 352         /*
 353          * check if the interface is available.
 354          * also check if SIOCGIFMEDIA ioctl is OK on the interface.
 355          */
 356         ifinfo->mediareqok = 1;
 357         ifinfo->active = interface_status(ifinfo);
 358         if (!ifinfo->mediareqok) {
 359                 /*
 360                  * probe routers periodically even if the link status
 361                  * does not change.
 362                  */
 363                 ifinfo->probeinterval = PROBE_INTERVAL;
 364         }
 365
 366         /* activate interface: interface_up returns 0 on success */
 367         flags = interface_up(ifinfo->ifname);
 368         if (flags == 0)
 369                 ifinfo->state = IFS_DELAY;
 370         else if (flags == IFS_TENTATIVE)
 371                 ifinfo->state = IFS_TENTATIVE;
 372         else
 373                 ifinfo->state = IFS_DOWN;
 374
 375         rtsol_timer_update(ifinfo);
 376
 377         /* link into chain */
 378         if (iflist)
 379                 ifinfo->next = iflist;
 380         iflist = ifinfo;
 381
 382         return(0);
 383
 384   bad:
 385         free(ifinfo->sdl);
 386         free(ifinfo);
 387         return(-1);
 388 }
 389
 390 #if 0
 391 static int
 392 ifreconfig(char *ifname)
 393 {
 394         struct ifinfo *ifi, *prev;
 395         int rv;
 396
 397         prev = NULL;
 398         for (ifi = iflist; ifi; ifi = ifi->next) {
 399                 if (strncmp(ifi->ifname, ifname, sizeof(ifi->ifname)) == 0)
 400                         break;
 401                 prev = ifi;
 402         }
 403         prev->next = ifi->next;
 404
 405         rv = ifconfig(ifname);
 406
 407         /* reclaim it after ifconfig() in case ifname is pointer inside ifi */
 408         if (ifi->rs_data)
 409                 free(ifi->rs_data);
 410         free(ifi->sdl);
 411         free(ifi);
 412
 413         return rv;
 414 }
 415 #endif
 416
 417 struct ifinfo *
 418 find_ifinfo(int ifindex)
 419 {
 420         struct ifinfo *ifi;
 421
 422         for (ifi = iflist; ifi; ifi = ifi->next)
 423                 if (ifi->sdl->sdl_index == ifindex)
 424                         return(ifi);
 425
 426         return(NULL);
 427 }
 428
 429 static int
 430 make_packet(struct ifinfo *ifinfo)
 431 {
 432         char *buf;
 433         struct nd_router_solicit *rs;
 434         size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
 435
 436         if ((lladdroptlen = lladdropt_length(ifinfo->sdl)) == 0) {
 437                 warnmsg(LOG_INFO, __func__,
 438                         "link-layer address option has null length"
 439                        " on %s. Treat as not included.", ifinfo->ifname);
 440         }
 441         packlen += lladdroptlen;
 442         ifinfo->rs_datalen = packlen;
 443
 444         /* allocate buffer */
 445         if ((buf = malloc(packlen)) == NULL) {
 446                 warnmsg(LOG_ERR, __func__,
 447                         "memory allocation failed for %s", ifinfo->ifname);
 448                 return(-1);
 449         }
 450         ifinfo->rs_data = buf;
 451
 452         /* fill in the message */
 453         rs = (struct nd_router_solicit *)buf;
 454         rs->nd_rs_type = ND_ROUTER_SOLICIT;
 455         rs->nd_rs_code = 0;
 456         rs->nd_rs_cksum = 0;
 457         rs->nd_rs_reserved = 0;
 458         buf += sizeof(*rs);
 459
 460         /* fill in source link-layer address option */
 461         if (lladdroptlen)
 462                 lladdropt_fill(ifinfo->sdl, (struct nd_opt_hdr *)buf);
 463
 464         return(0);
 465 }
 466
 467 static struct timeval *
 468 rtsol_check_timer(void)
 469 {
 470         static struct timeval returnval;
 471         struct timeval now, rtsol_timer;
 472         struct ifinfo *ifinfo;
 473         int flags;
 474
 475         gettimeofday(&now, NULL);
 476
 477         rtsol_timer = tm_max;
 478
 479         for (ifinfo = iflist; ifinfo; ifinfo = ifinfo->next) {
 480                 if (TIMEVAL_LEQ(ifinfo->expire, now)) {
 481                         if (dflag > 1)
 482                                 warnmsg(LOG_DEBUG, __func__,
 483                                         "timer expiration on %s, "
 484                                        "state = %d", ifinfo->ifname,
 485                                        ifinfo->state);
 486
 487                         switch (ifinfo->state) {
 488                         case IFS_DOWN:
 489                         case IFS_TENTATIVE:
 490                                 /* interface_up returns 0 on success */
 491                                 flags = interface_up(ifinfo->ifname);
 492                                 if (flags == 0)
 493                                         ifinfo->state = IFS_DELAY;
 494                                 else if (flags == IFS_TENTATIVE)
 495                                         ifinfo->state = IFS_TENTATIVE;
 496                                 else
 497                                         ifinfo->state = IFS_DOWN;
 498                                 break;
 499                         case IFS_IDLE:
 500                         {
 501                                 int oldstatus = ifinfo->active;
 502                                 int probe = 0;
 503
 504                                 ifinfo->active =
 505                                         interface_status(ifinfo);
 506
 507                                 if (oldstatus != ifinfo->active) {
 508                                         warnmsg(LOG_DEBUG, __func__,
 509                                                 "%s status is changed"
 510                                                 " from %d to %d",
 511                                                 ifinfo->ifname,
 512                                                 oldstatus, ifinfo->active);
 513                                         probe = 1;
 514                                         ifinfo->state = IFS_DELAY;
 515                                 }
 516                                 else if (ifinfo->probeinterval &&
 517                                          (ifinfo->probetimer -=
 518                                           ifinfo->timer.tv_sec) <= 0) {
 519                                         /* probe timer expired */
 520                                         ifinfo->probetimer =
 521                                                 ifinfo->probeinterval;
 522                                         probe = 1;
 523                                         ifinfo->state = IFS_PROBE;
 524                                 }
 525
 526                                 if (probe && mobile_node)
 527                                         defrouter_probe(ifinfo->sdl->sdl_index);
 528                                 break;
 529                         }
 530                         case IFS_DELAY:
 531                                 ifinfo->state = IFS_PROBE;
 532                                 sendpacket(ifinfo);
 533                                 break;
 534                         case IFS_PROBE:
 535                                 if (ifinfo->probes < MAX_RTR_SOLICITATIONS)
 536                                         sendpacket(ifinfo);
 537                                 else {
 538                                         warnmsg(LOG_INFO, __func__,
 539                                                 "No answer "
 540                                                 "after sending %d RSs",
 541                                                 ifinfo->probes);
 542                                         ifinfo->probes = 0;
 543                                         ifinfo->state = IFS_IDLE;
 544                                 }
 545                                 break;
 546                         }
 547                         rtsol_timer_update(ifinfo);
 548                 }
 549
 550                 if (TIMEVAL_LT(ifinfo->expire, rtsol_timer))
 551                         rtsol_timer = ifinfo->expire;
 552         }
 553
 554         if (TIMEVAL_EQ(rtsol_timer, tm_max)) {
 555                 warnmsg(LOG_DEBUG, __func__, "there is no timer");
 556                 return(NULL);
 557         }
 558         else if (TIMEVAL_LT(rtsol_timer, now))
 559                 /* this may occur when the interval is too small */
 560                 returnval.tv_sec = returnval.tv_usec = 0;
 561         else
 562                 TIMEVAL_SUB(&rtsol_timer, &now, &returnval);
 563
 564         if (dflag > 1)
 565                 warnmsg(LOG_DEBUG, __func__, "New timer is %ld:%08ld",
 566                         (long)returnval.tv_sec, (long)returnval.tv_usec);
 567
 568         return(&returnval);
 569 }
 570
 571 void
 572 rtsol_timer_update(struct ifinfo *ifinfo)
 573 {
 574 #define MILLION 1000000
 575 #define DADRETRY 10             /* XXX: adhoc */
 576         long interval;
 577         struct timeval now;
 578
 579         bzero(&ifinfo->timer, sizeof(ifinfo->timer));
 580
 581         switch (ifinfo->state) {
 582         case IFS_DOWN:
 583         case IFS_TENTATIVE:
 584                 if (++ifinfo->dadcount > DADRETRY) {
 585                         ifinfo->dadcount = 0;
 586                         ifinfo->timer.tv_sec = PROBE_INTERVAL;
 587                 }
 588                 else
 589                         ifinfo->timer.tv_sec = 1;
 590                 break;
 591         case IFS_IDLE:
 592                 if (mobile_node) {
 593                         /* XXX should be configurable */
 594                         ifinfo->timer.tv_sec = 3;
 595                 }
 596                 else
 597                         ifinfo->timer = tm_max; /* stop timer(valid?) */
 598                 break;
 599         case IFS_DELAY:
 600 #ifndef HAVE_ARC4RANDOM
 601                 interval = random() % (MAX_RTR_SOLICITATION_DELAY * MILLION);
 602 #else
 603                 interval = arc4random() % (MAX_RTR_SOLICITATION_DELAY * MILLION);
 604 #endif
 605                 ifinfo->timer.tv_sec = interval / MILLION;
 606                 ifinfo->timer.tv_usec = interval % MILLION;
 607                 break;
 608         case IFS_PROBE:
 609                 if (ifinfo->probes < MAX_RTR_SOLICITATIONS)
 610                         ifinfo->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
 611                 else {
 612                         /*
 613                          * After sending MAX_RTR_SOLICITATIONS solicitations,
 614                          * we're just waiting for possible replies; there
 615                          * will be no more solicatation.  Thus, we change
 616                          * the timer value to MAX_RTR_SOLICITATION_DELAY based
 617                          * on RFC 2461, Section 6.3.7.
 618                          */
 619                         ifinfo->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
 620                 }
 621                 break;
 622         default:
 623                 warnmsg(LOG_ERR, __func__,
 624                         "illegal interface state(%d) on %s",
 625                         ifinfo->state, ifinfo->ifname);
 626                 return;
 627         }
 628
 629         /* reset the timer */
 630         if (TIMEVAL_EQ(ifinfo->timer, tm_max)) {
 631                 ifinfo->expire = tm_max;
 632                 warnmsg(LOG_DEBUG, __func__,
 633                         "stop timer for %s", ifinfo->ifname);
 634         }
 635         else {
 636                 gettimeofday(&now, NULL);
 637                 TIMEVAL_ADD(&now, &ifinfo->timer, &ifinfo->expire);
 638
 639                 if (dflag > 1)
 640                         warnmsg(LOG_DEBUG, __func__,
 641                                 "set timer for %s to %d:%d", ifinfo->ifname,
 642                                (int)ifinfo->timer.tv_sec,
 643                                (int)ifinfo->timer.tv_usec);
 644         }
 645
 646 #undef MILLION
 647 }
 648
 649 /* timer related utility functions */
 650 #define MILLION 1000000
 651
 652 /* result = a + b */
 653 static void
 654 TIMEVAL_ADD(struct timeval *a, struct timeval *b, struct timeval *result)
 655 {
 656         long l;
 657
 658         if ((l = a->tv_usec + b->tv_usec) < MILLION) {
 659                 result->tv_usec = l;
 660                 result->tv_sec = a->tv_sec + b->tv_sec;
 661         }
 662         else {
 663                 result->tv_usec = l - MILLION;
 664                 result->tv_sec = a->tv_sec + b->tv_sec + 1;
 665         }
 666 }
 667
 668 /*
 669  * result = a - b
 670  * XXX: this function assumes that a >= b.
 671  */
 672 void
 673 TIMEVAL_SUB(struct timeval *a, struct timeval *b, struct timeval *result)
 674 {
 675         long l;
 676
 677         if ((l = a->tv_usec - b->tv_usec) >= 0) {
 678                 result->tv_usec = l;
 679                 result->tv_sec = a->tv_sec - b->tv_sec;
 680         }
 681         else {
 682                 result->tv_usec = MILLION + l;
 683                 result->tv_sec = a->tv_sec - b->tv_sec - 1;
 684         }
 685 }
 686
 687 static void
 688 rtsold_set_dump_file(int signo __unused)
 689 {
 690         do_dump = 1;
 691 }
 692
 693 static void
 694 usage(char *progname)
 695 {
 696         if (progname && progname[strlen(progname) - 1] != 'd') {
 697                 fprintf(stderr, "usage: rtsol [-dD] interfaces...\n");
 698                 fprintf(stderr, "usage: rtsol [-dD] -a\n");
 699         } else {
 700                 fprintf(stderr, "usage: rtsold [-adDfm1] interfaces...\n");
 701                 fprintf(stderr, "usage: rtsold [-dDfm1] -a\n");
 702         }
 703         exit(1);
 704 }
 705
 706 void
 707 warnmsg(int priority, const char *func, const char *msg, ...)
 708 {
 709         va_list ap;
 710         char buf[BUFSIZ];
 711
 712         va_start(ap, msg);
 713         if (fflag) {
 714                 if (priority <= log_upto) {
 715                         vfprintf(stderr, msg, ap);
 716                         fprintf(stderr, "\n");
 717                 }
 718         } else {
 719                 snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
 720                 msg = buf;
 721                 vsyslog(priority, msg, ap);
 722         }
 723         va_end(ap);
 724 }
 725
 726 static char **
 727 autoifprobe(void)
 728 {
 729 #ifndef HAVE_GETIFADDRS
 730         errx(1, "-a is not available with the configuration");
 731 #else
 732         static char ifname[IFNAMSIZ + 1];
 733         static char *argv[2];
 734         struct ifaddrs *ifap, *ifa, *target;
 735
 736         if (getifaddrs(&ifap) != 0)
 737                 return NULL;
 738
 739         target = NULL;
 740         /* find an ethernet */
 741         for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 742                 if ((ifa->ifa_flags & IFF_UP) == 0)
 743                         continue;
 744                 if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
 745                         continue;
 746                 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
 747                         continue;
 748                 if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
 749                         continue;
 750
 751                 if (ifa->ifa_addr->sa_family != AF_INET6)
 752                         continue;
 753
 754                 if (target && strcmp(target->ifa_name, ifa->ifa_name) == 0)
 755                         continue;
 756
 757                 if (!target)
 758                         target = ifa;
 759                 else {
 760                         /* if we find multiple candidates, failure. */
 761                         if (dflag > 1)
 762                                 warnx("multiple interfaces found");
 763                         target = NULL;
 764                         break;
 765                 }
 766         }
 767
 768         if (target) {
 769                 strncpy(ifname, target->ifa_name, sizeof(ifname) - 1);
 770                 ifname[sizeof(ifname) - 1] = '\0';
 771                 argv[0] = ifname;
 772                 argv[1] = NULL;
 773
 774                 if (dflag > 0)
 775                         warnx("probing %s", argv[0]);
 776         }
 777         freeifaddrs(ifap);
 778         if (target)
 779                 return argv;
 780         else
 781                 return NULL;
 782 #endif
 783 }