usr.sbin/rtsold/rtsold.c

   1 /*      $KAME: rtsold.c,v 1.67 2003/05/17 18:16:15 itojun Exp $ */
   2
   3 /*
   4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the project nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  * $FreeBSD$
  32  */
  33
  34 #include <sys/types.h>
  35 #include <sys/ioctl.h>
  36 #include <sys/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 #include <netinet/in_var.h>
  45 #include <arpa/inet.h>
  46
  47 #include <netinet6/nd6.h>
  48
  49 #include <signal.h>
  50 #include <unistd.h>
  51 #include <syslog.h>
  52 #include <string.h>
  53 #include <stdlib.h>
  54 #include <stdio.h>
  55 #include <time.h>
  56 #include <errno.h>
  57 #include <err.h>
  58 #include <stdarg.h>
  59 #include <ifaddrs.h>
  60 #include <poll.h>
  61
  62 #include "rtsold.h"
  63
  64 #define RTSOL_DUMPFILE  "/var/run/rtsold.dump";
  65 #define RTSOL_PIDFILE   "/var/run/rtsold.pid";
  66
  67 struct timespec tm_max;
  68 static int log_upto = 999;
  69 static int fflag = 0;
  70
  71 int Fflag = 0;  /* force setting sysctl parameters */
  72 int aflag = 0;
  73 int dflag = 0;
  74 int uflag = 0;
  75
  76 const char *otherconf_script;
  77 const char *resolvconf_script = "/sbin/resolvconf";
  78
  79 /* protocol constants */
  80 #define MAX_RTR_SOLICITATION_DELAY      1 /* second */
  81 #define RTR_SOLICITATION_INTERVAL       4 /* seconds */
  82 #define MAX_RTR_SOLICITATIONS           3 /* times */
  83
  84 /*
  85  * implementation dependent constants in seconds
  86  * XXX: should be configurable
  87  */
  88 #define PROBE_INTERVAL 60
  89
  90 /* static variables and functions */
  91 static int mobile_node = 0;
  92 static const char *pidfilename = RTSOL_PIDFILE;
  93
  94 #ifndef SMALL
  95 static int do_dump;
  96 static const char *dumpfilename = RTSOL_DUMPFILE;
  97 #endif
  98
  99 #if 0
 100 static int ifreconfig(char *);
 101 #endif
 102
 103 static int make_packet(struct ifinfo *);
 104 static struct timespec *rtsol_check_timer(void);
 105
 106 #ifndef SMALL
 107 static void rtsold_set_dump_file(int);
 108 #endif
 109 static void usage(void);
 110
 111 int
 112 main(int argc, char **argv)
 113 {
 114         int s, ch, once = 0;
 115         struct timespec *timeout;
 116         const char *opts;
 117         struct pollfd set[2];
 118         int rtsock;
 119         char *argv0;
 120
 121 #ifndef SMALL
 122         /* rtsold */
 123         opts = "adDfFm1O:p:R:u";
 124 #else
 125         /* rtsol */
 126         opts = "adDFO:R:u";
 127         fflag = 1;
 128         once = 1;
 129 #endif
 130         argv0 = argv[0];
 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 'F':
 147                         Fflag = 1;
 148                         break;
 149                 case 'm':
 150                         mobile_node = 1;
 151                         break;
 152                 case '1':
 153                         once = 1;
 154                         break;
 155                 case 'O':
 156                         otherconf_script = optarg;
 157                         break;
 158                 case 'p':
 159                         pidfilename = optarg;
 160                         break;
 161                 case 'R':
 162                         resolvconf_script = optarg;
 163                         break;
 164                 case 'u':
 165                         uflag = 1;
 166                         break;
 167                 default:
 168                         usage();
 169                         exit(1);
 170                 }
 171         }
 172         argc -= optind;
 173         argv += optind;
 174
 175         if ((!aflag && argc == 0) || (aflag && argc != 0)) {
 176                 usage();
 177                 exit(1);
 178         }
 179
 180         /* Generate maximum time in timespec. */
 181         tm_max.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
 182         tm_max.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
 183
 184         /* set log level */
 185         if (dflag > 1)
 186                 log_upto = LOG_DEBUG;
 187         else if (dflag > 0)
 188                 log_upto = LOG_INFO;
 189         else
 190                 log_upto = LOG_NOTICE;
 191
 192         if (!fflag) {
 193                 char *ident;
 194
 195                 ident = strrchr(argv0, '/');
 196                 if (!ident)
 197                         ident = argv0;
 198                 else
 199                         ident++;
 200                 openlog(ident, LOG_NDELAY|LOG_PID, LOG_DAEMON);
 201                 if (log_upto >= 0)
 202                         setlogmask(LOG_UPTO(log_upto));
 203         }
 204
 205         if (otherconf_script && *otherconf_script != '/') {
 206                 errx(1, "configuration script (%s) must be an absolute path",
 207                     otherconf_script);
 208         }
 209         if (resolvconf_script && *resolvconf_script != '/') {
 210                 errx(1, "configuration script (%s) must be an absolute path",
 211                     resolvconf_script);
 212         }
 213         if (pidfilename && *pidfilename != '/') {
 214                 errx(1, "pid filename (%s) must be an absolute path",
 215                     pidfilename);
 216         }
 217
 218 #if (__FreeBSD_version < 900000)
 219         if (Fflag) {
 220                 setinet6sysctl(IPV6CTL_FORWARDING, 0);
 221         } else {
 222                 /* warn if forwarding is up */
 223                 if (getinet6sysctl(IPV6CTL_FORWARDING))
 224                         warnx("kernel is configured as a router, not a host");
 225         }
 226 #endif
 227
 228 #ifndef SMALL
 229         /* initialization to dump internal status to a file */
 230         signal(SIGUSR1, rtsold_set_dump_file);
 231 #endif
 232
 233         if (!fflag)
 234                 daemon(0, 0);           /* act as a daemon */
 235
 236         /*
 237          * Open a socket for sending RS and receiving RA.
 238          * This should be done before calling ifinit(), since the function
 239          * uses the socket.
 240          */
 241         if ((s = sockopen()) < 0) {
 242                 warnmsg(LOG_ERR, __func__, "failed to open a socket");
 243                 exit(1);
 244         }
 245         set[0].fd = s;
 246         set[0].events = POLLIN;
 247         set[1].fd = -1;
 248
 249         if ((rtsock = rtsock_open()) < 0) {
 250                 warnmsg(LOG_ERR, __func__, "failed to open a socket");
 251                 exit(1);
 252         }
 253         set[1].fd = rtsock;
 254         set[1].events = POLLIN;
 255
 256         /* configuration per interface */
 257         if (ifinit()) {
 258                 warnmsg(LOG_ERR, __func__,
 259                     "failed to initialize interfaces");
 260                 exit(1);
 261         }
 262         if (aflag)
 263                 argv = autoifprobe();
 264         while (argv && *argv) {
 265                 if (ifconfig(*argv)) {
 266                         warnmsg(LOG_ERR, __func__,
 267                             "failed to initialize %s", *argv);
 268                         exit(1);
 269                 }
 270                 argv++;
 271         }
 272
 273         /* setup for probing default routers */
 274         if (probe_init()) {
 275                 warnmsg(LOG_ERR, __func__,
 276                     "failed to setup for probing routers");
 277                 exit(1);
 278                 /*NOTREACHED*/
 279         }
 280
 281         /* dump the current pid */
 282         if (!once) {
 283                 pid_t pid = getpid();
 284                 FILE *fp;
 285
 286                 if ((fp = fopen(pidfilename, "w")) == NULL)
 287                         warnmsg(LOG_ERR, __func__,
 288                             "failed to open a pid log file(%s): %s",
 289                             pidfilename, strerror(errno));
 290                 else {
 291                         fprintf(fp, "%d\n", pid);
 292                         fclose(fp);
 293                 }
 294         }
 295         while (1) {             /* main loop */
 296                 int e;
 297 #ifndef SMALL
 298                 if (do_dump) {  /* SIGUSR1 */
 299                         do_dump = 0;
 300                         rtsold_dump_file(dumpfilename);
 301                 }
 302 #endif
 303
 304                 timeout = rtsol_check_timer();
 305
 306                 if (once) {
 307                         struct ifinfo *ifi;
 308
 309                         /* if we have no timeout, we are done (or failed) */
 310                         if (timeout == NULL)
 311                                 break;
 312
 313                         /* if all interfaces have got RA packet, we are done */
 314                         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 315                                 if (ifi->state != IFS_DOWN && ifi->racnt == 0)
 316                                         break;
 317                         }
 318                         if (ifi == NULL)
 319                                 break;
 320                 }
 321                 e = poll(set, 2, timeout ? (timeout->tv_sec * 1000 + timeout->tv_nsec / 1000 / 1000) : INFTIM);
 322                 if (e < 1) {
 323                         if (e < 0 && errno != EINTR) {
 324                                 warnmsg(LOG_ERR, __func__, "select: %s",
 325                                     strerror(errno));
 326                         }
 327                         continue;
 328                 }
 329
 330                 /* packet reception */
 331                 if (set[1].revents & POLLIN)
 332                         rtsock_input(rtsock);
 333                 if (set[0].revents & POLLIN)
 334                         rtsol_input(s);
 335         }
 336         /* NOTREACHED */
 337
 338         return (0);
 339 }
 340
 341 int
 342 ifconfig(char *ifname)
 343 {
 344         struct ifinfo *ifi;
 345         struct sockaddr_dl *sdl;
 346         int flags;
 347
 348         if ((sdl = if_nametosdl(ifname)) == NULL) {
 349                 warnmsg(LOG_ERR, __func__,
 350                     "failed to get link layer information for %s", ifname);
 351                 return (-1);
 352         }
 353         if (find_ifinfo(sdl->sdl_index)) {
 354                 warnmsg(LOG_ERR, __func__,
 355                     "interface %s was already configured", ifname);
 356                 free(sdl);
 357                 return (-1);
 358         }
 359
 360         if (Fflag) {
 361                 struct in6_ndireq nd;
 362                 int s;
 363
 364                 if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
 365                         warnmsg(LOG_ERR, __func__, "socket() failed.");
 366                         return (-1);
 367                 }
 368                 memset(&nd, 0, sizeof(nd));
 369                 strlcpy(nd.ifname, ifname, sizeof(nd.ifname));
 370                 if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
 371                         warnmsg(LOG_ERR, __func__,
 372                             "cannot get accept_rtadv flag");
 373                         close(s);
 374                         return (-1);
 375                 }
 376                 nd.ndi.flags |= ND6_IFF_ACCEPT_RTADV;
 377                 if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd) < 0) {
 378                         warnmsg(LOG_ERR, __func__,
 379                             "cannot set accept_rtadv flag");
 380                         close(s);
 381                         return (-1);
 382                 }
 383                 close(s);
 384         }
 385
 386         if ((ifi = malloc(sizeof(*ifi))) == NULL) {
 387                 warnmsg(LOG_ERR, __func__, "memory allocation failed");
 388                 free(sdl);
 389                 return (-1);
 390         }
 391         memset(ifi, 0, sizeof(*ifi));
 392         ifi->sdl = sdl;
 393         ifi->ifi_rdnss = IFI_DNSOPT_STATE_NOINFO;
 394         ifi->ifi_dnssl = IFI_DNSOPT_STATE_NOINFO;
 395         TAILQ_INIT(&ifi->ifi_rainfo);
 396         strlcpy(ifi->ifname, ifname, sizeof(ifi->ifname));
 397
 398         /* construct a router solicitation message */
 399         if (make_packet(ifi))
 400                 goto bad;
 401
 402         /* set link ID of this interface. */
 403 #ifdef HAVE_SCOPELIB
 404         if (inet_zoneid(AF_INET6, 2, ifname, &ifi->linkid))
 405                 goto bad;
 406 #else
 407         /* XXX: assume interface IDs as link IDs */
 408         ifi->linkid = ifi->sdl->sdl_index;
 409 #endif
 410
 411         /*
 412          * check if the interface is available.
 413          * also check if SIOCGIFMEDIA ioctl is OK on the interface.
 414          */
 415         ifi->mediareqok = 1;
 416         ifi->active = interface_status(ifi);
 417         if (!ifi->mediareqok) {
 418                 /*
 419                  * probe routers periodically even if the link status
 420                  * does not change.
 421                  */
 422                 ifi->probeinterval = PROBE_INTERVAL;
 423         }
 424
 425         /* activate interface: interface_up returns 0 on success */
 426         flags = interface_up(ifi->ifname);
 427         if (flags == 0)
 428                 ifi->state = IFS_DELAY;
 429         else if (flags == IFS_TENTATIVE)
 430                 ifi->state = IFS_TENTATIVE;
 431         else
 432                 ifi->state = IFS_DOWN;
 433
 434         rtsol_timer_update(ifi);
 435
 436         TAILQ_INSERT_TAIL(&ifinfo_head, ifi, ifi_next);
 437         return (0);
 438
 439 bad:
 440         free(ifi->sdl);
 441         free(ifi);
 442         return (-1);
 443 }
 444
 445 void
 446 iflist_init(void)
 447 {
 448         struct ifinfo *ifi;
 449
 450         while ((ifi = TAILQ_FIRST(&ifinfo_head)) != NULL) {
 451                 TAILQ_REMOVE(&ifinfo_head, ifi, ifi_next);
 452                 if (ifi->sdl != NULL)
 453                         free(ifi->sdl);
 454                 if (ifi->rs_data != NULL)
 455                         free(ifi->rs_data);
 456                 free(ifi);
 457         }
 458 }
 459
 460 #if 0
 461 static int
 462 ifreconfig(char *ifname)
 463 {
 464         struct ifinfo *ifi, *prev;
 465         int rv;
 466
 467         prev = NULL;
 468         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 469                 if (strncmp(ifi->ifname, ifname, sizeof(ifi->ifname)) == 0)
 470                         break;
 471                 prev = ifi;
 472         }
 473         prev->next = ifi->next;
 474
 475         rv = ifconfig(ifname);
 476
 477         /* reclaim it after ifconfig() in case ifname is pointer inside ifi */
 478         if (ifi->rs_data)
 479                 free(ifi->rs_data);
 480         free(ifi->sdl);
 481         free(ifi);
 482
 483         return (rv);
 484 }
 485 #endif
 486
 487 struct rainfo *
 488 find_rainfo(struct ifinfo *ifi, struct sockaddr_in6 *sin6)
 489 {
 490         struct rainfo *rai;
 491
 492         TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next)
 493                 if (memcmp(&rai->rai_saddr.sin6_addr, &sin6->sin6_addr,
 494                     sizeof(rai->rai_saddr.sin6_addr)) == 0)
 495                         return (rai);
 496
 497         return (NULL);
 498 }
 499
 500 struct ifinfo *
 501 find_ifinfo(int ifindex)
 502 {
 503         struct ifinfo *ifi;
 504
 505         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 506                 if (ifi->sdl->sdl_index == ifindex)
 507                         return (ifi);
 508         }
 509         return (NULL);
 510 }
 511
 512 static int
 513 make_packet(struct ifinfo *ifi)
 514 {
 515         size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
 516         struct nd_router_solicit *rs;
 517         char *buf;
 518
 519         if ((lladdroptlen = lladdropt_length(ifi->sdl)) == 0) {
 520                 warnmsg(LOG_INFO, __func__,
 521                     "link-layer address option has null length"
 522                     " on %s. Treat as not included.", ifi->ifname);
 523         }
 524         packlen += lladdroptlen;
 525         ifi->rs_datalen = packlen;
 526
 527         /* allocate buffer */
 528         if ((buf = malloc(packlen)) == NULL) {
 529                 warnmsg(LOG_ERR, __func__,
 530                     "memory allocation failed for %s", ifi->ifname);
 531                 return (-1);
 532         }
 533         ifi->rs_data = buf;
 534
 535         /* fill in the message */
 536         rs = (struct nd_router_solicit *)buf;
 537         rs->nd_rs_type = ND_ROUTER_SOLICIT;
 538         rs->nd_rs_code = 0;
 539         rs->nd_rs_cksum = 0;
 540         rs->nd_rs_reserved = 0;
 541         buf += sizeof(*rs);
 542
 543         /* fill in source link-layer address option */
 544         if (lladdroptlen)
 545                 lladdropt_fill(ifi->sdl, (struct nd_opt_hdr *)buf);
 546
 547         return (0);
 548 }
 549
 550 static struct timespec *
 551 rtsol_check_timer(void)
 552 {
 553         static struct timespec returnval;
 554         struct timespec now, rtsol_timer;
 555         struct ifinfo *ifi;
 556         struct rainfo *rai;
 557         struct ra_opt *rao, *raotmp;
 558         int flags;
 559
 560         clock_gettime(CLOCK_MONOTONIC_FAST, &now);
 561
 562         rtsol_timer = tm_max;
 563
 564         TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
 565                 if (TS_CMP(&ifi->expire, &now, <=)) {
 566                         warnmsg(LOG_DEBUG, __func__, "timer expiration on %s, "
 567                             "state = %d", ifi->ifname, ifi->state);
 568
 569                         while((rai = TAILQ_FIRST(&ifi->ifi_rainfo)) != NULL) {
 570                                 /* Remove all RA options. */
 571                                 TAILQ_REMOVE(&ifi->ifi_rainfo, rai, rai_next);
 572                                 while ((rao = TAILQ_FIRST(&rai->rai_ra_opt)) !=
 573                                     NULL) {
 574                                         TAILQ_REMOVE(&rai->rai_ra_opt, rao,
 575                                             rao_next);
 576                                         if (rao->rao_msg != NULL)
 577                                                 free(rao->rao_msg);
 578                                         free(rao);
 579                                 }
 580                                 free(rai);
 581                         }
 582                         switch (ifi->state) {
 583                         case IFS_DOWN:
 584                         case IFS_TENTATIVE:
 585                                 /* interface_up returns 0 on success */
 586                                 flags = interface_up(ifi->ifname);
 587                                 if (flags == 0)
 588                                         ifi->state = IFS_DELAY;
 589                                 else if (flags == IFS_TENTATIVE)
 590                                         ifi->state = IFS_TENTATIVE;
 591                                 else
 592                                         ifi->state = IFS_DOWN;
 593                                 break;
 594                         case IFS_IDLE:
 595                         {
 596                                 int oldstatus = ifi->active;
 597                                 int probe = 0;
 598
 599                                 ifi->active = interface_status(ifi);
 600
 601                                 if (oldstatus != ifi->active) {
 602                                         warnmsg(LOG_DEBUG, __func__,
 603                                             "%s status is changed"
 604                                             " from %d to %d",
 605                                             ifi->ifname,
 606                                             oldstatus, ifi->active);
 607                                         probe = 1;
 608                                         ifi->state = IFS_DELAY;
 609                                 } else if (ifi->probeinterval &&
 610                                     (ifi->probetimer -=
 611                                     ifi->timer.tv_sec) <= 0) {
 612                                         /* probe timer expired */
 613                                         ifi->probetimer =
 614                                             ifi->probeinterval;
 615                                         probe = 1;
 616                                         ifi->state = IFS_PROBE;
 617                                 }
 618
 619                                 /*
 620                                  * If we need a probe, clear the previous
 621                                  * status wrt the "other" configuration.
 622                                  */
 623                                 if (probe)
 624                                         ifi->otherconfig = 0;
 625
 626                                 if (probe && mobile_node)
 627                                         defrouter_probe(ifi);
 628                                 break;
 629                         }
 630                         case IFS_DELAY:
 631                                 ifi->state = IFS_PROBE;
 632                                 sendpacket(ifi);
 633                                 break;
 634                         case IFS_PROBE:
 635                                 if (ifi->probes < MAX_RTR_SOLICITATIONS)
 636                                         sendpacket(ifi);
 637                                 else {
 638                                         warnmsg(LOG_INFO, __func__,
 639                                             "No answer after sending %d RSs",
 640                                             ifi->probes);
 641                                         ifi->probes = 0;
 642                                         ifi->state = IFS_IDLE;
 643                                 }
 644                                 break;
 645                         }
 646                         rtsol_timer_update(ifi);
 647                 } else {
 648                         /* Expiration check for RA options. */
 649                         int expire = 0;
 650
 651                         TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next) {
 652                                 TAILQ_FOREACH_SAFE(rao, &rai->rai_ra_opt,
 653                                     rao_next, raotmp) {
 654                                         warnmsg(LOG_DEBUG, __func__,
 655                                             "RA expiration timer: "
 656                                             "type=%d, msg=%s, expire=%s",
 657                                             rao->rao_type, (char *)rao->rao_msg,
 658                                                 sec2str(&rao->rao_expire));
 659                                         if (TS_CMP(&now, &rao->rao_expire,
 660                                             >=)) {
 661                                                 warnmsg(LOG_DEBUG, __func__,
 662                                                     "RA expiration timer: "
 663                                                     "expired.");
 664                                                 TAILQ_REMOVE(&rai->rai_ra_opt,
 665                                                     rao, rao_next);
 666                                                 if (rao->rao_msg != NULL)
 667                                                         free(rao->rao_msg);
 668                                                 free(rao);
 669                                                 expire = 1;
 670                                         }
 671                                 }
 672                         }
 673                         if (expire)
 674                                 ra_opt_handler(ifi);
 675                 }
 676                 if (TS_CMP(&ifi->expire, &rtsol_timer, <))
 677                         rtsol_timer = ifi->expire;
 678         }
 679
 680         if (TS_CMP(&rtsol_timer, &tm_max, ==)) {
 681                 warnmsg(LOG_DEBUG, __func__, "there is no timer");
 682                 return (NULL);
 683         } else if (TS_CMP(&rtsol_timer, &now, <))
 684                 /* this may occur when the interval is too small */
 685                 returnval.tv_sec = returnval.tv_nsec = 0;
 686         else
 687                 TS_SUB(&rtsol_timer, &now, &returnval);
 688
 689         now.tv_sec += returnval.tv_sec;
 690         now.tv_nsec += returnval.tv_nsec;
 691         warnmsg(LOG_DEBUG, __func__, "New timer is %s",
 692             sec2str(&now));
 693
 694         return (&returnval);
 695 }
 696
 697 void
 698 rtsol_timer_update(struct ifinfo *ifi)
 699 {
 700 #define MILLION 1000000
 701 #define DADRETRY 10             /* XXX: adhoc */
 702         long interval;
 703         struct timespec now;
 704
 705         bzero(&ifi->timer, sizeof(ifi->timer));
 706
 707         switch (ifi->state) {
 708         case IFS_DOWN:
 709         case IFS_TENTATIVE:
 710                 if (++ifi->dadcount > DADRETRY) {
 711                         ifi->dadcount = 0;
 712                         ifi->timer.tv_sec = PROBE_INTERVAL;
 713                 } else
 714                         ifi->timer.tv_sec = 1;
 715                 break;
 716         case IFS_IDLE:
 717                 if (mobile_node) {
 718                         /* XXX should be configurable */
 719                         ifi->timer.tv_sec = 3;
 720                 }
 721                 else
 722                         ifi->timer = tm_max;    /* stop timer(valid?) */
 723                 break;
 724         case IFS_DELAY:
 725                 interval = arc4random_uniform(MAX_RTR_SOLICITATION_DELAY * MILLION);
 726                 ifi->timer.tv_sec = interval / MILLION;
 727                 ifi->timer.tv_nsec = (interval % MILLION) * 1000;
 728                 break;
 729         case IFS_PROBE:
 730                 if (ifi->probes < MAX_RTR_SOLICITATIONS)
 731                         ifi->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
 732                 else {
 733                         /*
 734                          * After sending MAX_RTR_SOLICITATIONS solicitations,
 735                          * we're just waiting for possible replies; there
 736                          * will be no more solicitation.  Thus, we change
 737                          * the timer value to MAX_RTR_SOLICITATION_DELAY based
 738                          * on RFC 2461, Section 6.3.7.
 739                          */
 740                         ifi->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
 741                 }
 742                 break;
 743         default:
 744                 warnmsg(LOG_ERR, __func__,
 745                     "illegal interface state(%d) on %s",
 746                     ifi->state, ifi->ifname);
 747                 return;
 748         }
 749
 750         /* reset the timer */
 751         if (TS_CMP(&ifi->timer, &tm_max, ==)) {
 752                 ifi->expire = tm_max;
 753                 warnmsg(LOG_DEBUG, __func__,
 754                     "stop timer for %s", ifi->ifname);
 755         } else {
 756                 clock_gettime(CLOCK_MONOTONIC_FAST, &now);
 757                 TS_ADD(&now, &ifi->timer, &ifi->expire);
 758
 759                 now.tv_sec += ifi->timer.tv_sec;
 760                 now.tv_nsec += ifi->timer.tv_nsec;
 761                 warnmsg(LOG_DEBUG, __func__, "set timer for %s to %s",
 762                     ifi->ifname, sec2str(&now));
 763         }
 764
 765 #undef MILLION
 766 }
 767
 768 /* timer related utility functions */
 769 #define MILLION 1000000
 770
 771 #ifndef SMALL
 772 static void
 773 rtsold_set_dump_file(int sig __unused)
 774 {
 775         do_dump = 1;
 776 }
 777 #endif
 778
 779 static void
 780 usage(void)
 781 {
 782 #ifndef SMALL
 783         fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
 784             "[-p pidfile] [-R script-name] interface ...\n");
 785         fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
 786             "[-p pidfile] [-R script-name] -a\n");
 787 #else
 788         fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
 789             "[-p pidfile] [-R script-name] interface ...\n");
 790         fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
 791             "[-p pidfile] [-R script-name] -a\n");
 792 #endif
 793 }
 794
 795 void
 796 warnmsg(int priority, const char *func, const char *msg, ...)
 797 {
 798         va_list ap;
 799         char buf[BUFSIZ];
 800
 801         va_start(ap, msg);
 802         if (fflag) {
 803                 if (priority <= log_upto) {
 804                         (void)vfprintf(stderr, msg, ap);
 805                         (void)fprintf(stderr, "\n");
 806                 }
 807         } else {
 808                 snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
 809                 msg = buf;
 810                 vsyslog(priority, msg, ap);
 811         }
 812         va_end(ap);
 813 }
 814
 815 /*
 816  * return a list of interfaces which is suitable to sending an RS.
 817  */
 818 char **
 819 autoifprobe(void)
 820 {
 821         static char **argv = NULL;
 822         static int n = 0;
 823         char **a;
 824         int s = 0, i, found;
 825         struct ifaddrs *ifap, *ifa;
 826         struct in6_ndireq nd;
 827
 828         /* initialize */
 829         while (n--)
 830                 free(argv[n]);
 831         if (argv) {
 832                 free(argv);
 833                 argv = NULL;
 834         }
 835         n = 0;
 836
 837         if (getifaddrs(&ifap) != 0)
 838                 return (NULL);
 839
 840         if (!Fflag && (s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
 841                 warnmsg(LOG_ERR, __func__, "socket");
 842                 exit(1);
 843         }
 844
 845         /* find an ethernet */
 846         for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 847                 if ((ifa->ifa_flags & IFF_UP) == 0)
 848                         continue;
 849                 if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
 850                         continue;
 851                 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
 852                         continue;
 853                 if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
 854                         continue;
 855
 856                 if (ifa->ifa_addr->sa_family != AF_INET6)
 857                         continue;
 858
 859                 found = 0;
 860                 for (i = 0; i < n; i++) {
 861                         if (strcmp(argv[i], ifa->ifa_name) == 0) {
 862                                 found++;
 863                                 break;
 864                         }
 865                 }
 866                 if (found)
 867                         continue;
 868
 869                 /*
 870                  * Skip the interfaces which IPv6 and/or accepting RA
 871                  * is disabled.
 872                  */
 873                 if (!Fflag) {
 874                         memset(&nd, 0, sizeof(nd));
 875                         strlcpy(nd.ifname, ifa->ifa_name, sizeof(nd.ifname));
 876                         if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
 877                                 warnmsg(LOG_ERR, __func__,
 878                                         "ioctl(SIOCGIFINFO_IN6)");
 879                                 exit(1);
 880                         }
 881                         if ((nd.ndi.flags & ND6_IFF_IFDISABLED))
 882                                 continue;
 883                         if (!(nd.ndi.flags & ND6_IFF_ACCEPT_RTADV))
 884                                 continue;
 885                 }
 886
 887                 /* if we find multiple candidates, just warn. */
 888                 if (n != 0 && dflag > 1)
 889                         warnmsg(LOG_WARNING, __func__,
 890                                 "multiple interfaces found");
 891
 892                 a = realloc(argv, (n + 1) * sizeof(char *));
 893                 if (a == NULL) {
 894                         warnmsg(LOG_ERR, __func__, "realloc");
 895                         exit(1);
 896                 }
 897                 argv = a;
 898                 argv[n] = strdup(ifa->ifa_name);
 899                 if (!argv[n]) {
 900                         warnmsg(LOG_ERR, __func__, "malloc");
 901                         exit(1);
 902                 }
 903                 n++;
 904         }
 905
 906         if (n) {
 907                 a = realloc(argv, (n + 1) * sizeof(char *));
 908                 if (a == NULL) {
 909                         warnmsg(LOG_ERR, __func__, "realloc");
 910                         exit(1);
 911                 }
 912                 argv = a;
 913                 argv[n] = NULL;
 914
 915                 if (dflag > 0) {
 916                         for (i = 0; i < n; i++)
 917                                 warnmsg(LOG_WARNING, __func__, "probing %s",
 918                                         argv[i]);
 919                 }
 920         }
 921         if (!Fflag)
 922                 close(s);
 923         freeifaddrs(ifap);
 924         return (argv);
 925 }