usr.sbin/rtsold/rtsold.c

   1 /*      $KAME: rtsold.c,v 1.67 2003/05/17 18:16:15 itojun Exp $ */
   2
   3 /*-
   4  * SPDX-License-Identifier: BSD-3-Clause
   5  *
   6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * $FreeBSD$
  34  */
  35
  36 #include <sys/types.h>
  37 #include <sys/ioctl.h>
  38 #include <sys/socket.h>
  39 #include <sys/param.h>
  40
  41 #include <net/if.h>
  42 #include <net/if_dl.h>
  43
  44 #include <netinet/in.h>
  45 #include <netinet/icmp6.h>
  46 #include <netinet/in_var.h>
  47 #include <arpa/inet.h>
  48
  49 #include <netinet6/nd6.h>
  50
  51 #include <signal.h>
  52 #include <unistd.h>
  53 #include <syslog.h>
  54 #include <string.h>
  55 #include <stdlib.h>
  56 #include <stdio.h>
  57 #include <time.h>
  58 #include <errno.h>
  59 #include <err.h>
  60 #include <stdarg.h>
  61 #include <ifaddrs.h>
  62 #include <poll.h>
  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 timespec tm_max;
  70 static int log_upto = 999;
  71 static int fflag = 0;
  72
  73 int Fflag = 0;  /* force setting sysctl parameters */
  74 int aflag = 0;
  75 int dflag = 0;
  76 int uflag = 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 timespec *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 timespec *timeout;
 118         const char *opts;
 119         struct pollfd set[2];
 120         int rtsock;
 121         char *argv0;
 122
 123 #ifndef SMALL
 124         /* rtsold */
 125         opts = "adDfFm1O:p:R:u";
 126 #else
 127         /* rtsol */
 128         opts = "adDFO:R:u";
 129         fflag = 1;
 130         once = 1;
 131 #endif
 132         argv0 = argv[0];
 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                 case 'p':
 161                         pidfilename = optarg;
 162                         break;
 163                 case 'R':
 164                         resolvconf_script = optarg;
 165                         break;
 166                 case 'u':
 167                         uflag = 1;
 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         /* Generate maximum time in timespec. */
 183         tm_max.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
 184         tm_max.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
 185
 186         /* set log level */
 187         if (dflag > 1)
 188                 log_upto = LOG_DEBUG;
 189         else if (dflag > 0)
 190                 log_upto = LOG_INFO;
 191         else
 192                 log_upto = LOG_NOTICE;
 193
 194         if (!fflag) {
 195                 char *ident;
 196
 197                 ident = strrchr(argv0, '/');
 198                 if (!ident)
 199                         ident = argv0;
 200                 else
 201                         ident++;
 202                 openlog(ident, LOG_NDELAY|LOG_PID, LOG_DAEMON);
 203                 if (log_upto >= 0)
 204                         setlogmask(LOG_UPTO(log_upto));
 205         }
 206
 207         if (otherconf_script && *otherconf_script != '/') {
 208                 errx(1, "configuration script (%s) must be an absolute path",
 209                     otherconf_script);
 210         }
 211         if (resolvconf_script && *resolvconf_script != '/') {
 212                 errx(1, "configuration script (%s) must be an absolute path",
 213                     resolvconf_script);
 214         }
 215         if (pidfilename && *pidfilename != '/') {
 216                 errx(1, "pid filename (%s) must be an absolute path",
 217                     pidfilename);
 218         }
 219
 220 #if (__FreeBSD_version < 900000)
 221         if (Fflag) {
 222                 setinet6sysctl(IPV6CTL_FORWARDING, 0);
 223         } else {
 224                 /* warn if forwarding is up */
 225                 if (getinet6sysctl(IPV6CTL_FORWARDING))
 226                         warnx("kernel is configured as a router, not a host");
 227         }
 228 #endif
 229
 230 #ifndef SMALL
 231         /* initialization to dump internal status to a file */
 232         signal(SIGUSR1, rtsold_set_dump_file);
 233 #endif
 234
 235         if (!fflag)
 236                 daemon(0, 0);           /* act as a daemon */
 237
 238         /*
 239          * Open a socket for sending RS and receiving RA.
 240          * This should be done before calling ifinit(), since the function
 241          * uses the socket.
 242          */
 243         if ((s = sockopen()) < 0) {
 244                 warnmsg(LOG_ERR, __func__, "failed to open a socket");
 245                 exit(1);
 246         }
 247         set[0].fd = s;
 248         set[0].events = POLLIN;
 249         set[1].fd = -1;
 250
 251         if ((rtsock = rtsock_open()) < 0) {
 252                 warnmsg(LOG_ERR, __func__, "failed to open a socket");
 253                 exit(1);
 254         }
 255         set[1].fd = rtsock;
 256         set[1].events = POLLIN;
 257
 258         /* configuration per interface */
 259         if (ifinit()) {
 260                 warnmsg(LOG_ERR, __func__,
 261                     "failed to initialize interfaces");
 262                 exit(1);
 263         }
 264         if (aflag)
 265                 argv = autoifprobe();
 266         while (argv && *argv) {
 267                 if (ifconfig(*argv)) {
 268                         warnmsg(LOG_ERR, __func__,
 269                             "failed to initialize %s", *argv);
 270                         exit(1);
 271                 }
 272                 argv++;
 273         }
 274
 275         /* setup for probing default routers */
 276         if (probe_init()) {
 277                 warnmsg(LOG_ERR, __func__,
 278                     "failed to setup for probing routers");
 279                 exit(1);
 280                 /*NOTREACHED*/
 281         }
 282
 283         /* dump the current pid */
 284         if (!once) {
 285                 pid_t pid = getpid();
 286                 FILE *fp;
 287
 288                 if ((fp = fopen(pidfilename, "w")) == NULL)
 289                         warnmsg(LOG_ERR, __func__,
 290                             "failed to open a pid log file(%s): %s",
 291                             pidfilename, strerror(errno));
 292                 else {
 293                         fprintf(fp, "%d\n", pid);
 294                         fclose(fp);
 295                 }
 296         }
 297         while (1) {             /* main loop */
 298                 int e;
 299 #ifndef SMALL
 300                 if (do_dump) {  /* SIGUSR1 */
 301                         do_dump = 0;
 302                         rtsold_dump_file(dumpfilename);
 303                 }
 304 #endif
 305
 306                 timeout = rtsol_check_timer();
 307
 308                 if (once) {
 309                         struct ifinfo *ifi;
 310
 311                         /* if we have no timeout, we are done (or failed) */
 312                         if (timeout == NULL)
 313                                 break;
 314
 315                         /* if all interfaces have got RA packet, we are done */
 316                         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 317                                 if (ifi->state != IFS_DOWN && ifi->racnt == 0)
 318                                         break;
 319                         }
 320                         if (ifi == NULL)
 321                                 break;
 322                 }
 323                 e = poll(set, 2, timeout ? (timeout->tv_sec * 1000 + timeout->tv_nsec / 1000 / 1000) : INFTIM);
 324                 if (e < 1) {
 325                         if (e < 0 && errno != EINTR) {
 326                                 warnmsg(LOG_ERR, __func__, "select: %s",
 327                                     strerror(errno));
 328                         }
 329                         continue;
 330                 }
 331
 332                 /* packet reception */
 333                 if (set[1].revents & POLLIN)
 334                         rtsock_input(rtsock);
 335                 if (set[0].revents & POLLIN)
 336                         rtsol_input(s);
 337         }
 338         /* NOTREACHED */
 339
 340         return (0);
 341 }
 342
 343 int
 344 ifconfig(char *ifname)
 345 {
 346         struct ifinfo *ifi;
 347         struct sockaddr_dl *sdl;
 348         int flags;
 349
 350         if ((sdl = if_nametosdl(ifname)) == NULL) {
 351                 warnmsg(LOG_ERR, __func__,
 352                     "failed to get link layer information for %s", ifname);
 353                 return (-1);
 354         }
 355         if (find_ifinfo(sdl->sdl_index)) {
 356                 warnmsg(LOG_ERR, __func__,
 357                     "interface %s was already configured", ifname);
 358                 free(sdl);
 359                 return (-1);
 360         }
 361
 362         if (Fflag) {
 363                 struct in6_ndireq nd;
 364                 int s;
 365
 366                 if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
 367                         warnmsg(LOG_ERR, __func__, "socket() failed.");
 368                         return (-1);
 369                 }
 370                 memset(&nd, 0, sizeof(nd));
 371                 strlcpy(nd.ifname, ifname, sizeof(nd.ifname));
 372                 if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
 373                         warnmsg(LOG_ERR, __func__,
 374                             "cannot get accept_rtadv flag");
 375                         close(s);
 376                         return (-1);
 377                 }
 378                 nd.ndi.flags |= ND6_IFF_ACCEPT_RTADV;
 379                 if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd) < 0) {
 380                         warnmsg(LOG_ERR, __func__,
 381                             "cannot set accept_rtadv flag");
 382                         close(s);
 383                         return (-1);
 384                 }
 385                 close(s);
 386         }
 387
 388         if ((ifi = malloc(sizeof(*ifi))) == NULL) {
 389                 warnmsg(LOG_ERR, __func__, "memory allocation failed");
 390                 free(sdl);
 391                 return (-1);
 392         }
 393         memset(ifi, 0, sizeof(*ifi));
 394         ifi->sdl = sdl;
 395         ifi->ifi_rdnss = IFI_DNSOPT_STATE_NOINFO;
 396         ifi->ifi_dnssl = IFI_DNSOPT_STATE_NOINFO;
 397         TAILQ_INIT(&ifi->ifi_rainfo);
 398         strlcpy(ifi->ifname, ifname, sizeof(ifi->ifname));
 399
 400         /* construct a router solicitation message */
 401         if (make_packet(ifi))
 402                 goto bad;
 403
 404         /* set link ID of this interface. */
 405 #ifdef HAVE_SCOPELIB
 406         if (inet_zoneid(AF_INET6, 2, ifname, &ifi->linkid))
 407                 goto bad;
 408 #else
 409         /* XXX: assume interface IDs as link IDs */
 410         ifi->linkid = ifi->sdl->sdl_index;
 411 #endif
 412
 413         /*
 414          * check if the interface is available.
 415          * also check if SIOCGIFMEDIA ioctl is OK on the interface.
 416          */
 417         ifi->mediareqok = 1;
 418         ifi->active = interface_status(ifi);
 419         if (!ifi->mediareqok) {
 420                 /*
 421                  * probe routers periodically even if the link status
 422                  * does not change.
 423                  */
 424                 ifi->probeinterval = PROBE_INTERVAL;
 425         }
 426
 427         /* activate interface: interface_up returns 0 on success */
 428         flags = interface_up(ifi->ifname);
 429         if (flags == 0)
 430                 ifi->state = IFS_DELAY;
 431         else if (flags == IFS_TENTATIVE)
 432                 ifi->state = IFS_TENTATIVE;
 433         else
 434                 ifi->state = IFS_DOWN;
 435
 436         rtsol_timer_update(ifi);
 437
 438         TAILQ_INSERT_TAIL(&ifinfo_head, ifi, ifi_next);
 439         return (0);
 440
 441 bad:
 442         free(ifi->sdl);
 443         free(ifi);
 444         return (-1);
 445 }
 446
 447 void
 448 iflist_init(void)
 449 {
 450         struct ifinfo *ifi;
 451
 452         while ((ifi = TAILQ_FIRST(&ifinfo_head)) != NULL) {
 453                 TAILQ_REMOVE(&ifinfo_head, ifi, ifi_next);
 454                 if (ifi->sdl != NULL)
 455                         free(ifi->sdl);
 456                 if (ifi->rs_data != NULL)
 457                         free(ifi->rs_data);
 458                 free(ifi);
 459         }
 460 }
 461
 462 #if 0
 463 static int
 464 ifreconfig(char *ifname)
 465 {
 466         struct ifinfo *ifi, *prev;
 467         int rv;
 468
 469         prev = NULL;
 470         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 471                 if (strncmp(ifi->ifname, ifname, sizeof(ifi->ifname)) == 0)
 472                         break;
 473                 prev = ifi;
 474         }
 475         prev->next = ifi->next;
 476
 477         rv = ifconfig(ifname);
 478
 479         /* reclaim it after ifconfig() in case ifname is pointer inside ifi */
 480         if (ifi->rs_data)
 481                 free(ifi->rs_data);
 482         free(ifi->sdl);
 483         free(ifi);
 484
 485         return (rv);
 486 }
 487 #endif
 488
 489 struct rainfo *
 490 find_rainfo(struct ifinfo *ifi, struct sockaddr_in6 *sin6)
 491 {
 492         struct rainfo *rai;
 493
 494         TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next)
 495                 if (memcmp(&rai->rai_saddr.sin6_addr, &sin6->sin6_addr,
 496                     sizeof(rai->rai_saddr.sin6_addr)) == 0)
 497                         return (rai);
 498
 499         return (NULL);
 500 }
 501
 502 struct ifinfo *
 503 find_ifinfo(int ifindex)
 504 {
 505         struct ifinfo *ifi;
 506
 507         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 508                 if (ifi->sdl->sdl_index == ifindex)
 509                         return (ifi);
 510         }
 511         return (NULL);
 512 }
 513
 514 static int
 515 make_packet(struct ifinfo *ifi)
 516 {
 517         size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
 518         struct nd_router_solicit *rs;
 519         char *buf;
 520
 521         if ((lladdroptlen = lladdropt_length(ifi->sdl)) == 0) {
 522                 warnmsg(LOG_INFO, __func__,
 523                     "link-layer address option has null length"
 524                     " on %s. Treat as not included.", ifi->ifname);
 525         }
 526         packlen += lladdroptlen;
 527         ifi->rs_datalen = packlen;
 528
 529         /* allocate buffer */
 530         if ((buf = malloc(packlen)) == NULL) {
 531                 warnmsg(LOG_ERR, __func__,
 532                     "memory allocation failed for %s", ifi->ifname);
 533                 return (-1);
 534         }
 535         ifi->rs_data = buf;
 536
 537         /* fill in the message */
 538         rs = (struct nd_router_solicit *)buf;
 539         rs->nd_rs_type = ND_ROUTER_SOLICIT;
 540         rs->nd_rs_code = 0;
 541         rs->nd_rs_cksum = 0;
 542         rs->nd_rs_reserved = 0;
 543         buf += sizeof(*rs);
 544
 545         /* fill in source link-layer address option */
 546         if (lladdroptlen)
 547                 lladdropt_fill(ifi->sdl, (struct nd_opt_hdr *)buf);
 548
 549         return (0);
 550 }
 551
 552 static struct timespec *
 553 rtsol_check_timer(void)
 554 {
 555         static struct timespec returnval;
 556         struct timespec now, rtsol_timer;
 557         struct ifinfo *ifi;
 558         struct rainfo *rai;
 559         struct ra_opt *rao, *raotmp;
 560         int flags;
 561
 562         clock_gettime(CLOCK_MONOTONIC_FAST, &now);
 563
 564         rtsol_timer = tm_max;
 565
 566         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 567                 if (TS_CMP(&ifi->expire, &now, <=)) {
 568                         warnmsg(LOG_DEBUG, __func__, "timer expiration on %s, "
 569                             "state = %d", ifi->ifname, ifi->state);
 570
 571                         while((rai = TAILQ_FIRST(&ifi->ifi_rainfo)) != NULL) {
 572                                 /* Remove all RA options. */
 573                                 TAILQ_REMOVE(&ifi->ifi_rainfo, rai, rai_next);
 574                                 while ((rao = TAILQ_FIRST(&rai->rai_ra_opt)) !=
 575                                     NULL) {
 576                                         TAILQ_REMOVE(&rai->rai_ra_opt, rao,
 577                                             rao_next);
 578                                         if (rao->rao_msg != NULL)
 579                                                 free(rao->rao_msg);
 580                                         free(rao);
 581                                 }
 582                                 free(rai);
 583                         }
 584                         switch (ifi->state) {
 585                         case IFS_DOWN:
 586                         case IFS_TENTATIVE:
 587                                 /* interface_up returns 0 on success */
 588                                 flags = interface_up(ifi->ifname);
 589                                 if (flags == 0)
 590                                         ifi->state = IFS_DELAY;
 591                                 else if (flags == IFS_TENTATIVE)
 592                                         ifi->state = IFS_TENTATIVE;
 593                                 else
 594                                         ifi->state = IFS_DOWN;
 595                                 break;
 596                         case IFS_IDLE:
 597                         {
 598                                 int oldstatus = ifi->active;
 599                                 int probe = 0;
 600
 601                                 ifi->active = interface_status(ifi);
 602
 603                                 if (oldstatus != ifi->active) {
 604                                         warnmsg(LOG_DEBUG, __func__,
 605                                             "%s status is changed"
 606                                             " from %d to %d",
 607                                             ifi->ifname,
 608                                             oldstatus, ifi->active);
 609                                         probe = 1;
 610                                         ifi->state = IFS_DELAY;
 611                                 } else if (ifi->probeinterval &&
 612                                     (ifi->probetimer -=
 613                                     ifi->timer.tv_sec) <= 0) {
 614                                         /* probe timer expired */
 615                                         ifi->probetimer =
 616                                             ifi->probeinterval;
 617                                         probe = 1;
 618                                         ifi->state = IFS_PROBE;
 619                                 }
 620
 621                                 /*
 622                                  * If we need a probe, clear the previous
 623                                  * status wrt the "other" configuration.
 624                                  */
 625                                 if (probe)
 626                                         ifi->otherconfig = 0;
 627
 628                                 if (probe && mobile_node)
 629                                         defrouter_probe(ifi);
 630                                 break;
 631                         }
 632                         case IFS_DELAY:
 633                                 ifi->state = IFS_PROBE;
 634                                 sendpacket(ifi);
 635                                 break;
 636                         case IFS_PROBE:
 637                                 if (ifi->probes < MAX_RTR_SOLICITATIONS)
 638                                         sendpacket(ifi);
 639                                 else {
 640                                         warnmsg(LOG_INFO, __func__,
 641                                             "No answer after sending %d RSs",
 642                                             ifi->probes);
 643                                         ifi->probes = 0;
 644                                         ifi->state = IFS_IDLE;
 645                                 }
 646                                 break;
 647                         }
 648                         rtsol_timer_update(ifi);
 649                 } else {
 650                         /* Expiration check for RA options. */
 651                         int expire = 0;
 652
 653                         TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next) {
 654                                 TAILQ_FOREACH_SAFE(rao, &rai->rai_ra_opt,
 655                                     rao_next, raotmp) {
 656                                         warnmsg(LOG_DEBUG, __func__,
 657                                             "RA expiration timer: "
 658                                             "type=%d, msg=%s, expire=%s",
 659                                             rao->rao_type, (char *)rao->rao_msg,
 660                                                 sec2str(&rao->rao_expire));
 661                                         if (TS_CMP(&now, &rao->rao_expire,
 662                                             >=)) {
 663                                                 warnmsg(LOG_DEBUG, __func__,
 664                                                     "RA expiration timer: "
 665                                                     "expired.");
 666                                                 TAILQ_REMOVE(&rai->rai_ra_opt,
 667                                                     rao, rao_next);
 668                                                 if (rao->rao_msg != NULL)
 669                                                         free(rao->rao_msg);
 670                                                 free(rao);
 671                                                 expire = 1;
 672                                         }
 673                                 }
 674                         }
 675                         if (expire)
 676                                 ra_opt_handler(ifi);
 677                 }
 678                 if (TS_CMP(&ifi->expire, &rtsol_timer, <))
 679                         rtsol_timer = ifi->expire;
 680         }
 681
 682         if (TS_CMP(&rtsol_timer, &tm_max, ==)) {
 683                 warnmsg(LOG_DEBUG, __func__, "there is no timer");
 684                 return (NULL);
 685         } else if (TS_CMP(&rtsol_timer, &now, <))
 686                 /* this may occur when the interval is too small */
 687                 returnval.tv_sec = returnval.tv_nsec = 0;
 688         else
 689                 TS_SUB(&rtsol_timer, &now, &returnval);
 690
 691         now.tv_sec += returnval.tv_sec;
 692         now.tv_nsec += returnval.tv_nsec;
 693         warnmsg(LOG_DEBUG, __func__, "New timer is %s",
 694             sec2str(&now));
 695
 696         return (&returnval);
 697 }
 698
 699 void
 700 rtsol_timer_update(struct ifinfo *ifi)
 701 {
 702 #define MILLION 1000000
 703 #define DADRETRY 10             /* XXX: adhoc */
 704         long interval;
 705         struct timespec now;
 706
 707         bzero(&ifi->timer, sizeof(ifi->timer));
 708
 709         switch (ifi->state) {
 710         case IFS_DOWN:
 711         case IFS_TENTATIVE:
 712                 if (++ifi->dadcount > DADRETRY) {
 713                         ifi->dadcount = 0;
 714                         ifi->timer.tv_sec = PROBE_INTERVAL;
 715                 } else
 716                         ifi->timer.tv_sec = 1;
 717                 break;
 718         case IFS_IDLE:
 719                 if (mobile_node) {
 720                         /* XXX should be configurable */
 721                         ifi->timer.tv_sec = 3;
 722                 }
 723                 else
 724                         ifi->timer = tm_max;    /* stop timer(valid?) */
 725                 break;
 726         case IFS_DELAY:
 727                 interval = arc4random_uniform(MAX_RTR_SOLICITATION_DELAY * MILLION);
 728                 ifi->timer.tv_sec = interval / MILLION;
 729                 ifi->timer.tv_nsec = (interval % MILLION) * 1000;
 730                 break;
 731         case IFS_PROBE:
 732                 if (ifi->probes < MAX_RTR_SOLICITATIONS)
 733                         ifi->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
 734                 else {
 735                         /*
 736                          * After sending MAX_RTR_SOLICITATIONS solicitations,
 737                          * we're just waiting for possible replies; there
 738                          * will be no more solicitation.  Thus, we change
 739                          * the timer value to MAX_RTR_SOLICITATION_DELAY based
 740                          * on RFC 2461, Section 6.3.7.
 741                          */
 742                         ifi->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
 743                 }
 744                 break;
 745         default:
 746                 warnmsg(LOG_ERR, __func__,
 747                     "illegal interface state(%d) on %s",
 748                     ifi->state, ifi->ifname);
 749                 return;
 750         }
 751
 752         /* reset the timer */
 753         if (TS_CMP(&ifi->timer, &tm_max, ==)) {
 754                 ifi->expire = tm_max;
 755                 warnmsg(LOG_DEBUG, __func__,
 756                     "stop timer for %s", ifi->ifname);
 757         } else {
 758                 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
 759                 TS_ADD(&now, &ifi->timer, &ifi->expire);
 760
 761                 now.tv_sec += ifi->timer.tv_sec;
 762                 now.tv_nsec += ifi->timer.tv_nsec;
 763                 warnmsg(LOG_DEBUG, __func__, "set timer for %s to %s",
 764                     ifi->ifname, sec2str(&now));
 765         }
 766
 767 #undef MILLION
 768 }
 769
 770 /* timer related utility functions */
 771 #define MILLION 1000000
 772
 773 #ifndef SMALL
 774 static void
 775 rtsold_set_dump_file(int sig __unused)
 776 {
 777         do_dump = 1;
 778 }
 779 #endif
 780
 781 static void
 782 usage(void)
 783 {
 784 #ifndef SMALL
 785         fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
 786             "[-p pidfile] [-R script-name] interface ...\n");
 787         fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
 788             "[-p pidfile] [-R script-name] -a\n");
 789 #else
 790         fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
 791             "[-p pidfile] [-R script-name] interface ...\n");
 792         fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
 793             "[-p pidfile] [-R script-name] -a\n");
 794 #endif
 795 }
 796
 797 void
 798 warnmsg(int priority, const char *func, const char *msg, ...)
 799 {
 800         va_list ap;
 801         char buf[BUFSIZ];
 802
 803         va_start(ap, msg);
 804         if (fflag) {
 805                 if (priority <= log_upto) {
 806                         (void)vfprintf(stderr, msg, ap);
 807                         (void)fprintf(stderr, "\n");
 808                 }
 809         } else {
 810                 snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
 811                 msg = buf;
 812                 vsyslog(priority, msg, ap);
 813         }
 814         va_end(ap);
 815 }
 816
 817 /*
 818  * return a list of interfaces which is suitable to sending an RS.
 819  */
 820 char **
 821 autoifprobe(void)
 822 {
 823         static char **argv = NULL;
 824         static int n = 0;
 825         char **a;
 826         int s = 0, i, found;
 827         struct ifaddrs *ifap, *ifa;
 828         struct in6_ndireq nd;
 829
 830         /* initialize */
 831         while (n--)
 832                 free(argv[n]);
 833         if (argv) {
 834                 free(argv);
 835                 argv = NULL;
 836         }
 837         n = 0;
 838
 839         if (getifaddrs(&ifap) != 0)
 840                 return (NULL);
 841
 842         if (!Fflag && (s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
 843                 warnmsg(LOG_ERR, __func__, "socket");
 844                 exit(1);
 845         }
 846
 847         /* find an ethernet */
 848         for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 849                 if ((ifa->ifa_flags & IFF_UP) == 0)
 850                         continue;
 851                 if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
 852                         continue;
 853                 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
 854                         continue;
 855                 if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
 856                         continue;
 857
 858                 if (ifa->ifa_addr->sa_family != AF_INET6)
 859                         continue;
 860
 861                 found = 0;
 862                 for (i = 0; i < n; i++) {
 863                         if (strcmp(argv[i], ifa->ifa_name) == 0) {
 864                                 found++;
 865                                 break;
 866                         }
 867                 }
 868                 if (found)
 869                         continue;
 870
 871                 /*
 872                  * Skip the interfaces which IPv6 and/or accepting RA
 873                  * is disabled.
 874                  */
 875                 if (!Fflag) {
 876                         memset(&nd, 0, sizeof(nd));
 877                         strlcpy(nd.ifname, ifa->ifa_name, sizeof(nd.ifname));
 878                         if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
 879                                 warnmsg(LOG_ERR, __func__,
 880                                         "ioctl(SIOCGIFINFO_IN6)");
 881                                 exit(1);
 882                         }
 883                         if ((nd.ndi.flags & ND6_IFF_IFDISABLED))
 884                                 continue;
 885                         if (!(nd.ndi.flags & ND6_IFF_ACCEPT_RTADV))
 886                                 continue;
 887                 }
 888
 889                 /* if we find multiple candidates, just warn. */
 890                 if (n != 0 && dflag > 1)
 891                         warnmsg(LOG_WARNING, __func__,
 892                                 "multiple interfaces found");
 893
 894                 a = realloc(argv, (n + 1) * sizeof(char *));
 895                 if (a == NULL) {
 896                         warnmsg(LOG_ERR, __func__, "realloc");
 897                         exit(1);
 898                 }
 899                 argv = a;
 900                 argv[n] = strdup(ifa->ifa_name);
 901                 if (!argv[n]) {
 902                         warnmsg(LOG_ERR, __func__, "malloc");
 903                         exit(1);
 904                 }
 905                 n++;
 906         }
 907
 908         if (n) {
 909                 a = realloc(argv, (n + 1) * sizeof(char *));
 910                 if (a == NULL) {
 911                         warnmsg(LOG_ERR, __func__, "realloc");
 912                         exit(1);
 913                 }
 914                 argv = a;
 915                 argv[n] = NULL;
 916
 917                 if (dflag > 0) {
 918                         for (i = 0; i < n; i++)
 919                                 warnmsg(LOG_WARNING, __func__, "probing %s",
 920                                         argv[i]);
 921                 }
 922         }
 923         if (!Fflag)
 924                 close(s);
 925         freeifaddrs(ifap);
 926         return (argv);
 927 }