iptunnel.c

   1 /*
   2  * iptunnel.c          "ip tunnel"
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  *
  12  * Changes:
  13  *
  14  * Rani Assaf <rani@magic.metawire.com> 980929: resolve addresses
  15  * Rani Assaf <rani@magic.metawire.com> 980930: do not allow key for ipip/sit
  16  * Bernd Eckenfels 990715: add linux/types.h (not clean but solves missing __u16
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <unistd.h>
  23 #include <syslog.h>
  24 #include <fcntl.h>
  25 #include <sys/socket.h>
  26 #include <sys/ioctl.h>
  27 #include <linux/if.h>
  28 #include <linux/if_arp.h>
  29 #include <netinet/in.h>
  30 #include <netinet/ip.h>
  31 #include <arpa/inet.h>
  32 #include <linux/types.h>
  33 #include <linux/if_tunnel.h>
  34
  35 #include "config.h"
  36 #include "intl.h"
  37 #include "net-support.h"
  38 #include "version.h"
  39 #include "util.h"
  40
  41 #undef GRE_CSUM
  42 #define GRE_CSUM        htons(0x8000)
  43 #undef GRE_ROUTING
  44 #define GRE_ROUTING     htons(0x4000)
  45 #undef GRE_KEY
  46 #define GRE_KEY         htons(0x2000)
  47 #undef GRE_SEQ
  48 #define GRE_SEQ         htons(0x1000)
  49 #undef GRE_STRICT
  50 #define GRE_STRICT      htons(0x0800)
  51 #undef GRE_REC
  52 #define GRE_REC         htons(0x0700)
  53 #undef GRE_FLAGS
  54 #define GRE_FLAGS       htons(0x00F8)
  55 #undef GRE_VERSION
  56 #define GRE_VERSION     htons(0x0007)
  57
  58 /* Old versions of glibc do not define this */
  59 #if __GLIBC__ == 2 && __GLIBC_MINOR__ == 0
  60 #define IPPROTO_GRE     47
  61 #endif
  62
  63 #include "util-ank.h"
  64
  65 char *Release = RELEASE,
  66      *Version = "iptunnel 1.01",
  67      *Signature = "Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>";
  68
  69 static void version(void)
  70 {
  71         printf("%s\n%s\n%s\n", Release, Version, Signature);
  72         exit(E_VERSION);
  73 }
  74
  75 static void usage(void) __attribute__((noreturn));
  76
  77 static void usage(void)
  78 {
  79         fprintf(stderr, _("Usage: iptunnel { add | change | del | show } [ NAME ]\n"));
  80         fprintf(stderr, _("          [ mode { ipip | gre | sit } ] [ remote ADDR ] [ local ADDR ]\n"));
  81         fprintf(stderr, _("          [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n"));
  82         fprintf(stderr, _("          [ ttl TTL ] [ tos TOS ] [ nopmtudisc ] [ dev PHYS_DEV ]\n"));
  83         fprintf(stderr, _("       iptunnel -V | --version\n\n"));
  84         fprintf(stderr, _("Where: NAME := STRING\n"));
  85         fprintf(stderr, _("       ADDR := { IP_ADDRESS | any }\n"));
  86         fprintf(stderr, _("       TOS  := { NUMBER | inherit }\n"));
  87         fprintf(stderr, _("       TTL  := { 1..255 | inherit }\n"));
  88         fprintf(stderr, _("       KEY  := { DOTTED_QUAD | NUMBER }\n"));
  89         exit(-1);
  90 }
  91
  92 static int do_ioctl_get_ifindex(char *dev)
  93 {
  94         struct ifreq ifr;
  95         int fd;
  96         int err;
  97
  98         strcpy(ifr.ifr_name, dev);
  99         fd = socket(AF_INET, SOCK_DGRAM, 0);
 100         err = ioctl(fd, SIOCGIFINDEX, &ifr);
 101         if (err) {
 102                 perror("ioctl");
 103                 return 0;
 104         }
 105         close(fd);
 106         return ifr.ifr_ifindex;
 107 }
 108
 109 static int do_ioctl_get_iftype(char *dev)
 110 {
 111         struct ifreq ifr;
 112         int fd;
 113         int err;
 114
 115         strcpy(ifr.ifr_name, dev);
 116         fd = socket(AF_INET, SOCK_DGRAM, 0);
 117         err = ioctl(fd, SIOCGIFHWADDR, &ifr);
 118         if (err) {
 119                 perror("ioctl");
 120                 return -1;
 121         }
 122         close(fd);
 123         return ifr.ifr_addr.sa_family;
 124 }
 125
 126
 127 static char * do_ioctl_get_ifname(int idx)
 128 {
 129         static struct ifreq ifr;
 130         int fd;
 131         int err;
 132
 133         ifr.ifr_ifindex = idx;
 134         fd = socket(AF_INET, SOCK_DGRAM, 0);
 135         err = ioctl(fd, SIOCGIFNAME, &ifr);
 136         if (err) {
 137                 perror("ioctl");
 138                 return NULL;
 139         }
 140         close(fd);
 141         return ifr.ifr_name;
 142 }
 143
 144
 145
 146 static int do_get_ioctl(char *basedev, struct ip_tunnel_parm *p)
 147 {
 148         struct ifreq ifr;
 149         int fd;
 150         int err;
 151
 152         strcpy(ifr.ifr_name, basedev);
 153         ifr.ifr_ifru.ifru_data = (void*)p;
 154         fd = socket(AF_INET, SOCK_DGRAM, 0);
 155         err = ioctl(fd, SIOCGETTUNNEL, &ifr);
 156         if (err)
 157                 perror("ioctl");
 158         close(fd);
 159         return err;
 160 }
 161
 162 static int do_add_ioctl(int cmd, char *basedev, struct ip_tunnel_parm *p)
 163 {
 164         struct ifreq ifr;
 165         int fd;
 166         int err;
 167
 168         strcpy(ifr.ifr_name, basedev);
 169         ifr.ifr_ifru.ifru_data = (void*)p;
 170         fd = socket(AF_INET, SOCK_DGRAM, 0);
 171         err = ioctl(fd, cmd, &ifr);
 172         if (err)
 173                 perror("ioctl");
 174         close(fd);
 175         return err;
 176 }
 177
 178 static int do_del_ioctl(char *basedev, struct ip_tunnel_parm *p)
 179 {
 180         struct ifreq ifr;
 181         int fd;
 182         int err;
 183
 184         strcpy(ifr.ifr_name, basedev);
 185         ifr.ifr_ifru.ifru_data = (void*)p;
 186         fd = socket(AF_INET, SOCK_DGRAM, 0);
 187         err = ioctl(fd, SIOCDELTUNNEL, &ifr);
 188         if (err)
 189                 perror("ioctl");
 190         close(fd);
 191         return err;
 192 }
 193
 194 static int parse_args(int argc, char **argv, struct ip_tunnel_parm *p)
 195 {
 196         char medium[IFNAMSIZ];
 197
 198         memset(p, 0, sizeof(*p));
 199         memset(&medium, 0, sizeof(medium));
 200
 201         p->iph.version = 4;
 202         p->iph.ihl = 5;
 203 #ifndef IP_DF
 204 #define IP_DF           0x4000          /* Flag: "Don't Fragment"       */
 205 #endif
 206         p->iph.frag_off = htons(IP_DF);
 207
 208         while (argc > 0) {
 209                 if (strcmp(*argv, "mode") == 0) {
 210                         NEXT_ARG();
 211                         if (strcmp(*argv, "ipip") == 0) {
 212                                 if (p->iph.protocol)
 213                                         usage();
 214                                 p->iph.protocol = IPPROTO_IPIP;
 215                         } else if (strcmp(*argv, "gre") == 0) {
 216                                 if (p->iph.protocol)
 217                                         usage();
 218                                 p->iph.protocol = IPPROTO_GRE;
 219                         } else if (strcmp(*argv, "sit") == 0) {
 220                                 if (p->iph.protocol)
 221                                         usage();
 222                                 p->iph.protocol = IPPROTO_IPV6;
 223                         } else
 224                                 usage();
 225                 } else if (strcmp(*argv, "key") == 0) {
 226                         unsigned uval;
 227                         NEXT_ARG();
 228                         p->i_flags |= GRE_KEY;
 229                         p->o_flags |= GRE_KEY;
 230                         if (strchr(*argv, '.'))
 231                                 p->i_key = p->o_key = get_addr32(*argv);
 232                         else {
 233                                 if (scan_number(*argv, &uval)<0)
 234                                         usage();
 235                                 p->i_key = p->o_key = htonl(uval);
 236                         }
 237                 } else if (strcmp(*argv, "ikey") == 0) {
 238                         unsigned uval;
 239                         NEXT_ARG();
 240                         p->i_flags |= GRE_KEY;
 241                         if (strchr(*argv, '.'))
 242                                 p->o_key = get_addr32(*argv);
 243                         else {
 244                                 if (scan_number(*argv, &uval)<0)
 245                                         usage();
 246                                 p->i_key = htonl(uval);
 247                         }
 248                 } else if (strcmp(*argv, "okey") == 0) {
 249                         unsigned uval;
 250                         NEXT_ARG();
 251                         p->o_flags |= GRE_KEY;
 252                         if (strchr(*argv, '.'))
 253                                 p->o_key = get_addr32(*argv);
 254                         else {
 255                                 if (scan_number(*argv, &uval)<0)
 256                                         usage();
 257                                 p->o_key = htonl(uval);
 258                         }
 259                 } else if (strcmp(*argv, "seq") == 0) {
 260                         p->i_flags |= GRE_SEQ;
 261                         p->o_flags |= GRE_SEQ;
 262                 } else if (strcmp(*argv, "iseq") == 0) {
 263                         p->i_flags |= GRE_SEQ;
 264                 } else if (strcmp(*argv, "oseq") == 0) {
 265                         p->o_flags |= GRE_SEQ;
 266                 } else if (strcmp(*argv, "csum") == 0) {
 267                         p->i_flags |= GRE_CSUM;
 268                         p->o_flags |= GRE_CSUM;
 269                 } else if (strcmp(*argv, "icsum") == 0) {
 270                         p->i_flags |= GRE_CSUM;
 271                 } else if (strcmp(*argv, "ocsum") == 0) {
 272                         p->o_flags |= GRE_CSUM;
 273                 } else if (strcmp(*argv, "nopmtudisc") == 0) {
 274                         p->iph.frag_off = 0;
 275                 } else if (strcmp(*argv, "remote") == 0) {
 276                         NEXT_ARG();
 277                         if (strcmp(*argv, "any"))
 278                                 p->iph.daddr = get_addr32(*argv);
 279                 } else if (strcmp(*argv, "local") == 0) {
 280                         NEXT_ARG();
 281                         if (strcmp(*argv, "any"))
 282                                 p->iph.saddr = get_addr32(*argv);
 283                 } else if (strcmp(*argv, "dev") == 0) {
 284                         NEXT_ARG();
 285                         safe_strncpy(medium, *argv, IFNAMSIZ-1);
 286                 } else if (strcmp(*argv, "ttl") == 0) {
 287                         unsigned uval;
 288                         NEXT_ARG();
 289                         if (strcmp(*argv, "inherit") != 0) {
 290                                 if (scan_number(*argv, &uval)<0)
 291                                         usage();
 292                                 if (uval > 255)
 293                                         usage();
 294                                 p->iph.ttl = uval;
 295                         }
 296                 } else if (strcmp(*argv, "tos") == 0) {
 297                         unsigned uval;
 298                         NEXT_ARG();
 299                         if (strcmp(*argv, "inherit") != 0) {
 300                                 if (scan_number(*argv, &uval)<0)
 301                                         usage();
 302                                 if (uval > 255)
 303                                         usage();
 304                                 p->iph.tos = uval;
 305                         } else
 306                                 p->iph.tos = 1;
 307                 } else {
 308                         if (p->name[0])
 309                                 usage();
 310                         safe_strncpy(p->name, *argv, IFNAMSIZ);
 311                 }
 312                 argc--; argv++;
 313         }
 314
 315         if (p->iph.protocol == 0) {
 316                 if (memcmp(p->name, "gre", 3) == 0)
 317                         p->iph.protocol = IPPROTO_GRE;
 318                 else if (memcmp(p->name, "ipip", 4) == 0)
 319                         p->iph.protocol = IPPROTO_IPIP;
 320                 else if (memcmp(p->name, "sit", 3) == 0)
 321                         p->iph.protocol = IPPROTO_IPV6;
 322         }
 323
 324         if (p->iph.protocol == IPPROTO_IPIP || p->iph.protocol == IPPROTO_IPV6) {
 325                 if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) {
 326                         fprintf(stderr, _("Keys are not allowed with ipip and sit.\n"));
 327                         return -1;
 328                 }
 329         }
 330
 331         if (medium[0]) {
 332                 p->link = do_ioctl_get_ifindex(medium);
 333                 if (p->link == 0)
 334                         return -1;
 335         }
 336
 337         if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
 338                 p->i_key = p->iph.daddr;
 339                 p->i_flags |= GRE_KEY;
 340         }
 341         if (p->o_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
 342                 p->o_key = p->iph.daddr;
 343                 p->o_flags |= GRE_KEY;
 344         }
 345         if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) {
 346                 fprintf(stderr, _("Broadcast tunnel requires a source address.\n"));
 347                 return -1;
 348         }
 349         return 0;
 350 }
 351
 352
 353 static int do_add(int cmd, int argc, char **argv)
 354 {
 355         struct ip_tunnel_parm p;
 356
 357         if (parse_args(argc, argv, &p) < 0)
 358                 return -1;
 359
 360         if (p.iph.ttl && p.iph.frag_off == 0) {
 361                 fprintf(stderr, _("ttl != 0 and noptmudisc are incompatible\n"));
 362                 return -1;
 363         }
 364
 365         switch (p.iph.protocol) {
 366         case IPPROTO_IPIP:
 367                 return do_add_ioctl(cmd, "tunl0", &p);
 368         case IPPROTO_GRE:
 369                 return do_add_ioctl(cmd, "gre0", &p);
 370         case IPPROTO_IPV6:
 371                 return do_add_ioctl(cmd, "sit0", &p);
 372         default:
 373                 fprintf(stderr, _("cannot determine tunnel mode (ipip, gre or sit)\n"));
 374                 return -1;
 375         }
 376         return -1;
 377 }
 378
 379 int do_del(int argc, char **argv)
 380 {
 381         struct ip_tunnel_parm p;
 382
 383         if (parse_args(argc, argv, &p) < 0)
 384                 return -1;
 385
 386         switch (p.iph.protocol) {
 387         case IPPROTO_IPIP:
 388                 return do_del_ioctl(p.name[0] ? p.name : "tunl0", &p);
 389         case IPPROTO_GRE:
 390                 return do_del_ioctl(p.name[0] ? p.name : "gre0", &p);
 391         case IPPROTO_IPV6:
 392                 return do_del_ioctl(p.name[0] ? p.name : "sit0", &p);
 393         default:
 394                 return do_del_ioctl(p.name, &p);
 395         }
 396         return -1;
 397 }
 398
 399 void print_tunnel(struct ip_tunnel_parm *p)
 400 {
 401         char s1[256];
 402         char s2[256];
 403         char s3[64];
 404         char s4[64];
 405
 406         format_host(AF_INET, &p->iph.daddr, s1, sizeof(s1));
 407         format_host(AF_INET, &p->iph.saddr, s2, sizeof(s2));
 408         inet_ntop(AF_INET, &p->i_key, s3, sizeof(s3));
 409         inet_ntop(AF_INET, &p->o_key, s4, sizeof(s4));
 410
 411         printf(_("%s: %s/ip  remote %s  local %s "),
 412                p->name,
 413                p->iph.protocol == IPPROTO_IPIP ? "ip" :
 414                (p->iph.protocol == IPPROTO_GRE ? "gre" :
 415                 (p->iph.protocol == IPPROTO_IPV6 ? "ipv6" : _("unknown"))),
 416                p->iph.daddr ? s1 : "any", p->iph.saddr ? s2 : "any");
 417         if (p->link) {
 418                 char *n = do_ioctl_get_ifname(p->link);
 419                 if (n)
 420                         printf(" dev %s ", n);
 421         }
 422         if (p->iph.ttl)
 423                 printf(" ttl %d ", p->iph.ttl);
 424         else
 425                 printf(" ttl inherit ");
 426         if (p->iph.tos) {
 427                 printf(" tos");
 428                 if (p->iph.tos&1)
 429                         printf(" inherit");
 430                 if (p->iph.tos&~1)
 431                         printf("%c%02x ", p->iph.tos&1 ? '/' : ' ', p->iph.tos&~1);
 432         }
 433         if (!(p->iph.frag_off&htons(IP_DF)))
 434                 printf(" nopmtudisc");
 435
 436         if ((p->i_flags&GRE_KEY) && (p->o_flags&GRE_KEY) && p->o_key == p->i_key)
 437                 printf(" key %s", s3);
 438         else if ((p->i_flags|p->o_flags)&GRE_KEY) {
 439                 if (p->i_flags&GRE_KEY)
 440                         printf(" ikey %s ", s3);
 441                 if (p->o_flags&GRE_KEY)
 442                         printf(" okey %s ", s4);
 443         }
 444         printf("\n");
 445
 446         if (p->i_flags&GRE_SEQ)
 447                 printf(_("  Drop packets out of sequence.\n"));
 448         if (p->i_flags&GRE_CSUM)
 449                 printf(_("  Checksum in received packet is required.\n"));
 450         if (p->o_flags&GRE_SEQ)
 451                 printf(_("  Sequence packets on output.\n"));
 452         if (p->o_flags&GRE_CSUM)
 453                 printf(_("  Checksum output packets.\n"));
 454 }
 455
 456 static int do_tunnels_list(struct ip_tunnel_parm *p)
 457 {
 458         char name[IFNAMSIZ];
 459         unsigned long  rx_bytes, rx_packets, rx_errs, rx_drops,
 460         rx_fifo, rx_frame,
 461         tx_bytes, tx_packets, tx_errs, tx_drops,
 462         tx_fifo, tx_colls, tx_carrier, rx_multi;
 463         int type;
 464         struct ip_tunnel_parm p1;
 465
 466         char buf[512];
 467         FILE *fp = fopen("/proc/net/dev", "r");
 468         if (fp == NULL) {
 469                 perror("fopen");
 470                 return -1;
 471         }
 472
 473         fgets(buf, sizeof(buf), fp);
 474         fgets(buf, sizeof(buf), fp);
 475
 476         while (fgets(buf, sizeof(buf), fp) != NULL) {
 477                 char *ptr;
 478                 buf[sizeof(buf) - 1] = 0;
 479                 if ((ptr = strchr(buf, ':')) == NULL ||
 480                     (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) {
 481                         fprintf(stderr, _("Wrong format of /proc/net/dev. Sorry.\n"));
 482                         return -1;
 483                 }
 484                 if (sscanf(ptr, "%ld%ld%ld%ld%ld%ld%ld%*d%ld%ld%ld%ld%ld%ld%ld",
 485                            &rx_bytes, &rx_packets, &rx_errs, &rx_drops,
 486                            &rx_fifo, &rx_frame, &rx_multi,
 487                            &tx_bytes, &tx_packets, &tx_errs, &tx_drops,
 488                            &tx_fifo, &tx_colls, &tx_carrier) != 14)
 489                         continue;
 490                 if (p->name[0] && strcmp(p->name, name))
 491                         continue;
 492                 type = do_ioctl_get_iftype(name);
 493                 if (type == -1) {
 494                         fprintf(stderr, _("Failed to get type of [%s]\n"), name);
 495                         continue;
 496                 }
 497                 if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT)
 498                         continue;
 499                 memset(&p1, 0, sizeof(p1));
 500                 if (do_get_ioctl(name, &p1))
 501                         continue;
 502                 if ((p->link && p1.link != p->link) ||
 503                     (p->name[0] && strcmp(p1.name, p->name)) ||
 504                     (p->iph.daddr && p1.iph.daddr != p->iph.daddr) ||
 505                     (p->iph.saddr && p1.iph.saddr != p->iph.saddr) ||
 506                     (p->i_key && p1.i_key != p->i_key))
 507                         continue;
 508                 print_tunnel(&p1);
 509                 if (show_stats) {
 510                         printf(_("RX: Packets    Bytes        Errors CsumErrs OutOfSeq Mcasts\n"));
 511                         printf("    %-10ld %-12ld %-6ld %-8ld %-8ld %-8ld\n",
 512                                rx_packets, rx_bytes, rx_errs, rx_frame, rx_fifo, rx_multi);
 513                         printf(_("TX: Packets    Bytes        Errors DeadLoop NoRoute  NoBufs\n"));
 514                         printf("    %-10ld %-12ld %-6ld %-8ld %-8ld %-6ld\n\n",
 515                                tx_packets, tx_bytes, tx_errs, tx_colls, tx_carrier, tx_drops);
 516                 }
 517         }
 518         return 0;
 519 }
 520
 521 static int do_show(int argc, char **argv)
 522 {
 523         int err;
 524         struct ip_tunnel_parm p;
 525
 526         if (parse_args(argc, argv, &p) < 0)
 527                 return -1;
 528
 529         switch (p.iph.protocol) {
 530         case IPPROTO_IPIP:
 531                 err = do_get_ioctl(p.name[0] ? p.name : "tunl0", &p);
 532                 break;
 533         case IPPROTO_GRE:
 534                 err = do_get_ioctl(p.name[0] ? p.name : "gre0", &p);
 535                 break;
 536         case IPPROTO_IPV6:
 537                 err = do_get_ioctl(p.name[0] ? p.name : "sit0", &p);
 538                 break;
 539         default:
 540                 do_tunnels_list(&p);
 541                 return 0;
 542         }
 543         if (err)
 544                 return -1;
 545
 546         print_tunnel(&p);
 547         return 0;
 548 }
 549
 550 int do_iptunnel(int argc, char **argv)
 551 {
 552         if (argc > 0) {
 553                 if (matches(*argv, "add") == 0)
 554                         return do_add(SIOCADDTUNNEL, argc-1, argv+1);
 555                 if (matches(*argv, "change") == 0)
 556                         return do_add(SIOCCHGTUNNEL, argc-1, argv+1);
 557                 if (matches(*argv, "del") == 0)
 558                         return do_del(argc-1, argv+1);
 559                 if (matches(*argv, "show") == 0 ||
 560                     matches(*argv, "lst") == 0 ||
 561                     matches(*argv, "list") == 0)
 562                         return do_show(argc-1, argv+1);
 563         } else
 564                 return do_show(0, NULL);
 565
 566         usage();
 567 }
 568
 569
 570 int preferred_family = AF_UNSPEC;
 571 int show_stats = 0;
 572 int resolve_hosts = 0;
 573
 574 int main(int argc, char **argv)
 575 {
 576         char *basename;
 577
 578 #if I18N
 579         bindtextdomain("net-tools", "/usr/share/locale");
 580         textdomain("net-tools");
 581 #endif
 582
 583         basename = strrchr(argv[0], '/');
 584         if (basename == NULL)
 585                 basename = argv[0];
 586         else
 587                 basename++;
 588
 589         while (argc > 1) {
 590                 if (argv[1][0] != '-')
 591                         break;
 592                 if (matches(argv[1], "-family") == 0) {
 593                         argc--;
 594                         argv++;
 595                         if (argc <= 1)
 596                                 usage();
 597                         if (strcmp(argv[1], "inet") == 0)
 598                                 preferred_family = AF_INET;
 599                         else if (strcmp(argv[1], "inet6") == 0)
 600                                 preferred_family = AF_INET6;
 601                         else
 602                                 usage();
 603                 } else if (matches(argv[1], "-stats") == 0 ||
 604                            matches(argv[1], "-statistics") == 0) {
 605                         ++show_stats;
 606                 } else if (matches(argv[1], "-resolve") == 0) {
 607                         ++resolve_hosts;
 608                 } else if ((matches(argv[1], "-V") == 0) || (matches(argv[1], "--version") == 0)) {
 609                         version();
 610                 } else
 611                         usage();
 612                 argc--; argv++;
 613         }
 614
 615         return do_iptunnel(argc-1, argv+1);
 616 }