ip/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
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <unistd.h>
  17 #include <sys/types.h>
  18 #include <sys/socket.h>
  19 #include <arpa/inet.h>
  20 #include <sys/ioctl.h>
  21 #include <linux/if.h>
  22 #include <linux/if_arp.h>
  23 #include <linux/ip.h>
  24 #include <linux/if_tunnel.h>
  25
  26 #include "rt_names.h"
  27 #include "utils.h"
  28 #include "ip_common.h"
  29 #include "tunnel.h"
  30
  31 static void usage(void) __attribute__((noreturn));
  32
  33 static void usage(void)
  34 {
  35         fprintf(stderr, "Usage: ip tunnel { add | change | del | show | prl | 6rd } [ NAME ]\n");
  36         fprintf(stderr, "          [ mode { ipip | gre | sit | isatap } ] [ remote ADDR ] [ local ADDR ]\n");
  37         fprintf(stderr, "          [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n");
  38         fprintf(stderr, "          [ prl-default ADDR ] [ prl-nodefault ADDR ] [ prl-delete ADDR ]\n");
  39         fprintf(stderr, "          [ 6rd-prefix ADDR ] [ 6rd-relay_prefix ADDR ] [ 6rd-reset ]\n");
  40         fprintf(stderr, "          [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [ dev PHYS_DEV ]\n");
  41         fprintf(stderr, "\n");
  42         fprintf(stderr, "Where: NAME := STRING\n");
  43         fprintf(stderr, "       ADDR := { IP_ADDRESS | any }\n");
  44         fprintf(stderr, "       TOS  := { NUMBER | inherit }\n");
  45         fprintf(stderr, "       TTL  := { 1..255 | inherit }\n");
  46         fprintf(stderr, "       KEY  := { DOTTED_QUAD | NUMBER }\n");
  47         exit(-1);
  48 }
  49
  50 static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
  51 {
  52         int count = 0;
  53         char medium[IFNAMSIZ];
  54         int isatap = 0;
  55
  56         memset(p, 0, sizeof(*p));
  57         memset(&medium, 0, sizeof(medium));
  58
  59         p->iph.version = 4;
  60         p->iph.ihl = 5;
  61 #ifndef IP_DF
  62 #define IP_DF           0x4000          /* Flag: "Don't Fragment"       */
  63 #endif
  64         p->iph.frag_off = htons(IP_DF);
  65
  66         while (argc > 0) {
  67                 if (strcmp(*argv, "mode") == 0) {
  68                         NEXT_ARG();
  69                         if (strcmp(*argv, "ipip") == 0 ||
  70                             strcmp(*argv, "ip/ip") == 0) {
  71                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_IPIP) {
  72                                         fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
  73                                         exit(-1);
  74                                 }
  75                                 p->iph.protocol = IPPROTO_IPIP;
  76                         } else if (strcmp(*argv, "gre") == 0 ||
  77                                    strcmp(*argv, "gre/ip") == 0) {
  78                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_GRE) {
  79                                         fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
  80                                         exit(-1);
  81                                 }
  82                                 p->iph.protocol = IPPROTO_GRE;
  83                         } else if (strcmp(*argv, "sit") == 0 ||
  84                                    strcmp(*argv, "ipv6/ip") == 0) {
  85                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_IPV6) {
  86                                         fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
  87                                         exit(-1);
  88                                 }
  89                                 p->iph.protocol = IPPROTO_IPV6;
  90                         } else if (strcmp(*argv, "isatap") == 0) {
  91                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_IPV6) {
  92                                         fprintf(stderr, "You managed to ask for more than one tunnel mode.\n");
  93                                         exit(-1);
  94                                 }
  95                                 p->iph.protocol = IPPROTO_IPV6;
  96                                 isatap++;
  97                         } else {
  98                                 fprintf(stderr,"Cannot guess tunnel mode.\n");
  99                                 exit(-1);
 100                         }
 101                 } else if (strcmp(*argv, "key") == 0) {
 102                         unsigned uval;
 103                         NEXT_ARG();
 104                         p->i_flags |= GRE_KEY;
 105                         p->o_flags |= GRE_KEY;
 106                         if (strchr(*argv, '.'))
 107                                 p->i_key = p->o_key = get_addr32(*argv);
 108                         else {
 109                                 if (get_unsigned(&uval, *argv, 0)<0) {
 110                                         fprintf(stderr, "invalid value of \"key\"\n");
 111                                         exit(-1);
 112                                 }
 113                                 p->i_key = p->o_key = htonl(uval);
 114                         }
 115                 } else if (strcmp(*argv, "ikey") == 0) {
 116                         unsigned uval;
 117                         NEXT_ARG();
 118                         p->i_flags |= GRE_KEY;
 119                         if (strchr(*argv, '.'))
 120                                 p->i_key = get_addr32(*argv);
 121                         else {
 122                                 if (get_unsigned(&uval, *argv, 0)<0) {
 123                                         fprintf(stderr, "invalid value of \"ikey\"\n");
 124                                         exit(-1);
 125                                 }
 126                                 p->i_key = htonl(uval);
 127                         }
 128                 } else if (strcmp(*argv, "okey") == 0) {
 129                         unsigned uval;
 130                         NEXT_ARG();
 131                         p->o_flags |= GRE_KEY;
 132                         if (strchr(*argv, '.'))
 133                                 p->o_key = get_addr32(*argv);
 134                         else {
 135                                 if (get_unsigned(&uval, *argv, 0)<0) {
 136                                         fprintf(stderr, "invalid value of \"okey\"\n");
 137                                         exit(-1);
 138                                 }
 139                                 p->o_key = htonl(uval);
 140                         }
 141                 } else if (strcmp(*argv, "seq") == 0) {
 142                         p->i_flags |= GRE_SEQ;
 143                         p->o_flags |= GRE_SEQ;
 144                 } else if (strcmp(*argv, "iseq") == 0) {
 145                         p->i_flags |= GRE_SEQ;
 146                 } else if (strcmp(*argv, "oseq") == 0) {
 147                         p->o_flags |= GRE_SEQ;
 148                 } else if (strcmp(*argv, "csum") == 0) {
 149                         p->i_flags |= GRE_CSUM;
 150                         p->o_flags |= GRE_CSUM;
 151                 } else if (strcmp(*argv, "icsum") == 0) {
 152                         p->i_flags |= GRE_CSUM;
 153                 } else if (strcmp(*argv, "ocsum") == 0) {
 154                         p->o_flags |= GRE_CSUM;
 155                 } else if (strcmp(*argv, "nopmtudisc") == 0) {
 156                         p->iph.frag_off = 0;
 157                 } else if (strcmp(*argv, "pmtudisc") == 0) {
 158                         p->iph.frag_off = htons(IP_DF);
 159                 } else if (strcmp(*argv, "remote") == 0) {
 160                         NEXT_ARG();
 161                         if (strcmp(*argv, "any"))
 162                                 p->iph.daddr = get_addr32(*argv);
 163                 } else if (strcmp(*argv, "local") == 0) {
 164                         NEXT_ARG();
 165                         if (strcmp(*argv, "any"))
 166                                 p->iph.saddr = get_addr32(*argv);
 167                 } else if (strcmp(*argv, "dev") == 0) {
 168                         NEXT_ARG();
 169                         strncpy(medium, *argv, IFNAMSIZ-1);
 170                 } else if (strcmp(*argv, "ttl") == 0 ||
 171                            strcmp(*argv, "hoplimit") == 0) {
 172                         unsigned uval;
 173                         NEXT_ARG();
 174                         if (strcmp(*argv, "inherit") != 0) {
 175                                 if (get_unsigned(&uval, *argv, 0))
 176                                         invarg("invalid TTL\n", *argv);
 177                                 if (uval > 255)
 178                                         invarg("TTL must be <=255\n", *argv);
 179                                 p->iph.ttl = uval;
 180                         }
 181                 } else if (strcmp(*argv, "tos") == 0 ||
 182                            strcmp(*argv, "tclass") == 0 ||
 183                            matches(*argv, "dsfield") == 0) {
 184                         __u32 uval;
 185                         NEXT_ARG();
 186                         if (strcmp(*argv, "inherit") != 0) {
 187                                 if (rtnl_dsfield_a2n(&uval, *argv))
 188                                         invarg("bad TOS value", *argv);
 189                                 p->iph.tos = uval;
 190                         } else
 191                                 p->iph.tos = 1;
 192                 } else {
 193                         if (strcmp(*argv, "name") == 0) {
 194                                 NEXT_ARG();
 195                         } else if (matches(*argv, "help") == 0)
 196                                 usage();
 197                         if (p->name[0])
 198                                 duparg2("name", *argv);
 199                         strncpy(p->name, *argv, IFNAMSIZ);
 200                         if (cmd == SIOCCHGTUNNEL && count == 0) {
 201                                 struct ip_tunnel_parm old_p;
 202                                 memset(&old_p, 0, sizeof(old_p));
 203                                 if (tnl_get_ioctl(*argv, &old_p))
 204                                         return -1;
 205                                 *p = old_p;
 206                         }
 207                 }
 208                 count++;
 209                 argc--; argv++;
 210         }
 211
 212
 213         if (p->iph.protocol == 0) {
 214                 if (memcmp(p->name, "gre", 3) == 0)
 215                         p->iph.protocol = IPPROTO_GRE;
 216                 else if (memcmp(p->name, "ipip", 4) == 0)
 217                         p->iph.protocol = IPPROTO_IPIP;
 218                 else if (memcmp(p->name, "sit", 3) == 0)
 219                         p->iph.protocol = IPPROTO_IPV6;
 220                 else if (memcmp(p->name, "isatap", 6) == 0) {
 221                         p->iph.protocol = IPPROTO_IPV6;
 222                         isatap++;
 223                 }
 224         }
 225
 226         if (p->iph.protocol == IPPROTO_IPIP || p->iph.protocol == IPPROTO_IPV6) {
 227                 if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) {
 228                         fprintf(stderr, "Keys are not allowed with ipip and sit.\n");
 229                         return -1;
 230                 }
 231         }
 232
 233         if (medium[0]) {
 234                 p->link = tnl_ioctl_get_ifindex(medium);
 235                 if (p->link == 0)
 236                         return -1;
 237         }
 238
 239         if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
 240                 p->i_key = p->iph.daddr;
 241                 p->i_flags |= GRE_KEY;
 242         }
 243         if (p->o_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
 244                 p->o_key = p->iph.daddr;
 245                 p->o_flags |= GRE_KEY;
 246         }
 247         if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) {
 248                 fprintf(stderr, "Broadcast tunnel requires a source address.\n");
 249                 return -1;
 250         }
 251         if (isatap)
 252                 p->i_flags |= SIT_ISATAP;
 253
 254         return 0;
 255 }
 256
 257
 258 static int do_add(int cmd, int argc, char **argv)
 259 {
 260         struct ip_tunnel_parm p;
 261
 262         if (parse_args(argc, argv, cmd, &p) < 0)
 263                 return -1;
 264
 265         if (p.iph.ttl && p.iph.frag_off == 0) {
 266                 fprintf(stderr, "ttl != 0 and noptmudisc are incompatible\n");
 267                 return -1;
 268         }
 269
 270         switch (p.iph.protocol) {
 271         case IPPROTO_IPIP:
 272                 return tnl_add_ioctl(cmd, "tunl0", p.name, &p);
 273         case IPPROTO_GRE:
 274                 return tnl_add_ioctl(cmd, "gre0", p.name, &p);
 275         case IPPROTO_IPV6:
 276                 return tnl_add_ioctl(cmd, "sit0", p.name, &p);
 277         default:
 278                 fprintf(stderr, "cannot determine tunnel mode (ipip, gre or sit)\n");
 279                 return -1;
 280         }
 281         return -1;
 282 }
 283
 284 static int do_del(int argc, char **argv)
 285 {
 286         struct ip_tunnel_parm p;
 287
 288         if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0)
 289                 return -1;
 290
 291         switch (p.iph.protocol) {
 292         case IPPROTO_IPIP:
 293                 return tnl_del_ioctl("tunl0", p.name, &p);
 294         case IPPROTO_GRE:
 295                 return tnl_del_ioctl("gre0", p.name, &p);
 296         case IPPROTO_IPV6:
 297                 return tnl_del_ioctl("sit0", p.name, &p);
 298         default:
 299                 return tnl_del_ioctl(p.name, p.name, &p);
 300         }
 301         return -1;
 302 }
 303
 304 static void print_tunnel(struct ip_tunnel_parm *p)
 305 {
 306         struct ip_tunnel_6rd ip6rd;
 307         char s1[1024];
 308         char s2[1024];
 309         char s3[64];
 310         char s4[64];
 311
 312         memset(&ip6rd, 0, sizeof(ip6rd));
 313         inet_ntop(AF_INET, &p->i_key, s3, sizeof(s3));
 314         inet_ntop(AF_INET, &p->o_key, s4, sizeof(s4));
 315
 316         /* Do not use format_host() for local addr,
 317          * symbolic name will not be useful.
 318          */
 319         printf("%s: %s/ip  remote %s  local %s ",
 320                p->name,
 321                tnl_strproto(p->iph.protocol),
 322                p->iph.daddr ? format_host(AF_INET, 4, &p->iph.daddr, s1, sizeof(s1))  : "any",
 323                p->iph.saddr ? rt_addr_n2a(AF_INET, 4, &p->iph.saddr, s2, sizeof(s2)) : "any");
 324
 325         if (p->i_flags & SIT_ISATAP) {
 326                 struct ip_tunnel_prl prl[16];
 327                 int i;
 328
 329                 memset(prl, 0, sizeof(prl));
 330                 prl[0].datalen = sizeof(prl) - sizeof(prl[0]);
 331                 prl[0].addr = htonl(INADDR_ANY);
 332
 333                 if (!tnl_prl_ioctl(SIOCGETPRL, p->name, prl))
 334                         for (i = 1; i < sizeof(prl) / sizeof(prl[0]); i++)
 335                 {
 336                         if (prl[i].addr != htonl(INADDR_ANY)) {
 337                                 printf(" %s %s ",
 338                                         (prl[i].flags & PRL_DEFAULT) ? "pdr" : "pr",
 339                                         format_host(AF_INET, 4, &prl[i].addr, s1, sizeof(s1)));
 340                         }
 341                 }
 342         }
 343
 344         if (p->link) {
 345                 char *n = tnl_ioctl_get_ifname(p->link);
 346                 if (n)
 347                         printf(" dev %s ", n);
 348         }
 349
 350         if (p->iph.ttl)
 351                 printf(" ttl %d ", p->iph.ttl);
 352         else
 353                 printf(" ttl inherit ");
 354
 355         if (p->iph.tos) {
 356                 SPRINT_BUF(b1);
 357                 printf(" tos");
 358                 if (p->iph.tos&1)
 359                         printf(" inherit");
 360                 if (p->iph.tos&~1)
 361                         printf("%c%s ", p->iph.tos&1 ? '/' : ' ',
 362                                rtnl_dsfield_n2a(p->iph.tos&~1, b1, sizeof(b1)));
 363         }
 364
 365         if (!(p->iph.frag_off&htons(IP_DF)))
 366                 printf(" nopmtudisc");
 367
 368         if (!tnl_ioctl_get_6rd(p->name, &ip6rd) && ip6rd.prefixlen) {
 369                 printf(" 6rd-prefix %s/%u ",
 370                        inet_ntop(AF_INET6, &ip6rd.prefix, s1, sizeof(s1)),
 371                        ip6rd.prefixlen);
 372                 if (ip6rd.relay_prefix) {
 373                         printf("6rd-relay_prefix %s/%u ",
 374                                format_host(AF_INET, 4, &ip6rd.relay_prefix, s1, sizeof(s1)),
 375                                ip6rd.relay_prefixlen);
 376                 }
 377         }
 378
 379         if ((p->i_flags&GRE_KEY) && (p->o_flags&GRE_KEY) && p->o_key == p->i_key)
 380                 printf(" key %s", s3);
 381         else if ((p->i_flags|p->o_flags)&GRE_KEY) {
 382                 if (p->i_flags&GRE_KEY)
 383                         printf(" ikey %s ", s3);
 384                 if (p->o_flags&GRE_KEY)
 385                         printf(" okey %s ", s4);
 386         }
 387
 388         if (p->i_flags&GRE_SEQ)
 389                 printf("%s  Drop packets out of sequence.\n", _SL_);
 390         if (p->i_flags&GRE_CSUM)
 391                 printf("%s  Checksum in received packet is required.", _SL_);
 392         if (p->o_flags&GRE_SEQ)
 393                 printf("%s  Sequence packets on output.", _SL_);
 394         if (p->o_flags&GRE_CSUM)
 395                 printf("%s  Checksum output packets.", _SL_);
 396 }
 397
 398 static int do_tunnels_list(struct ip_tunnel_parm *p)
 399 {
 400         char name[IFNAMSIZ];
 401         unsigned long  rx_bytes, rx_packets, rx_errs, rx_drops,
 402         rx_fifo, rx_frame,
 403         tx_bytes, tx_packets, tx_errs, tx_drops,
 404         tx_fifo, tx_colls, tx_carrier, rx_multi;
 405         int type;
 406         struct ip_tunnel_parm p1;
 407
 408         char buf[512];
 409         FILE *fp = fopen("/proc/net/dev", "r");
 410         if (fp == NULL) {
 411                 perror("fopen");
 412                 return -1;
 413         }
 414
 415         fgets(buf, sizeof(buf), fp);
 416         fgets(buf, sizeof(buf), fp);
 417
 418         while (fgets(buf, sizeof(buf), fp) != NULL) {
 419                 char *ptr;
 420                 buf[sizeof(buf) - 1] = 0;
 421                 if ((ptr = strchr(buf, ':')) == NULL ||
 422                     (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) {
 423                         fprintf(stderr, "Wrong format of /proc/net/dev. Sorry.\n");
 424                         return -1;
 425                 }
 426                 if (sscanf(ptr, "%ld%ld%ld%ld%ld%ld%ld%*d%ld%ld%ld%ld%ld%ld%ld",
 427                            &rx_bytes, &rx_packets, &rx_errs, &rx_drops,
 428                            &rx_fifo, &rx_frame, &rx_multi,
 429                            &tx_bytes, &tx_packets, &tx_errs, &tx_drops,
 430                            &tx_fifo, &tx_colls, &tx_carrier) != 14)
 431                         continue;
 432                 if (p->name[0] && strcmp(p->name, name))
 433                         continue;
 434                 type = tnl_ioctl_get_iftype(name);
 435                 if (type == -1) {
 436                         fprintf(stderr, "Failed to get type of [%s]\n", name);
 437                         continue;
 438                 }
 439                 if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT)
 440                         continue;
 441                 memset(&p1, 0, sizeof(p1));
 442                 if (tnl_get_ioctl(name, &p1))
 443                         continue;
 444                 if ((p->link && p1.link != p->link) ||
 445                     (p->name[0] && strcmp(p1.name, p->name)) ||
 446                     (p->iph.daddr && p1.iph.daddr != p->iph.daddr) ||
 447                     (p->iph.saddr && p1.iph.saddr != p->iph.saddr) ||
 448                     (p->i_key && p1.i_key != p->i_key))
 449                         continue;
 450                 print_tunnel(&p1);
 451                 if (show_stats) {
 452                         printf("%s", _SL_);
 453                         printf("RX: Packets    Bytes        Errors CsumErrs OutOfSeq Mcasts%s", _SL_);
 454                         printf("    %-10ld %-12ld %-6ld %-8ld %-8ld %-8ld%s",
 455                                rx_packets, rx_bytes, rx_errs, rx_frame, rx_fifo, rx_multi, _SL_);
 456                         printf("TX: Packets    Bytes        Errors DeadLoop NoRoute  NoBufs%s", _SL_);
 457                         printf("    %-10ld %-12ld %-6ld %-8ld %-8ld %-6ld",
 458                                tx_packets, tx_bytes, tx_errs, tx_colls, tx_carrier, tx_drops);
 459                 }
 460                 printf("\n");
 461         }
 462         return 0;
 463 }
 464
 465 static int do_show(int argc, char **argv)
 466 {
 467         int err;
 468         struct ip_tunnel_parm p;
 469
 470         if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0)
 471                 return -1;
 472
 473         switch (p.iph.protocol) {
 474         case IPPROTO_IPIP:
 475                 err = tnl_get_ioctl(p.name[0] ? p.name : "tunl0", &p);
 476                 break;
 477         case IPPROTO_GRE:
 478                 err = tnl_get_ioctl(p.name[0] ? p.name : "gre0", &p);
 479                 break;
 480         case IPPROTO_IPV6:
 481                 err = tnl_get_ioctl(p.name[0] ? p.name : "sit0", &p);
 482                 break;
 483         default:
 484                 do_tunnels_list(&p);
 485                 return 0;
 486         }
 487         if (err)
 488                 return -1;
 489
 490         print_tunnel(&p);
 491         printf("\n");
 492         return 0;
 493 }
 494
 495 static int do_prl(int argc, char **argv)
 496 {
 497         struct ip_tunnel_prl p;
 498         int count = 0;
 499         int devname = 0;
 500         int cmd = 0;
 501         char medium[IFNAMSIZ];
 502
 503         memset(&p, 0, sizeof(p));
 504         memset(&medium, 0, sizeof(medium));
 505
 506         while (argc > 0) {
 507                 if (strcmp(*argv, "prl-default") == 0) {
 508                         NEXT_ARG();
 509                         cmd = SIOCADDPRL;
 510                         p.addr = get_addr32(*argv);
 511                         p.flags |= PRL_DEFAULT;
 512                         count++;
 513                 } else if (strcmp(*argv, "prl-nodefault") == 0) {
 514                         NEXT_ARG();
 515                         cmd = SIOCADDPRL;
 516                         p.addr = get_addr32(*argv);
 517                         count++;
 518                 } else if (strcmp(*argv, "prl-delete") == 0) {
 519                         NEXT_ARG();
 520                         cmd = SIOCDELPRL;
 521                         p.addr = get_addr32(*argv);
 522                         count++;
 523                 } else if (strcmp(*argv, "dev") == 0) {
 524                         NEXT_ARG();
 525                         strncpy(medium, *argv, IFNAMSIZ-1);
 526                         devname++;
 527                 } else {
 528                         fprintf(stderr,"%s: Invalid PRL parameter.\n", *argv);
 529                         exit(-1);
 530                 }
 531                 if (count > 1) {
 532                         fprintf(stderr,"One PRL entry at a time.\n");
 533                         exit(-1);
 534                 }
 535                 argc--; argv++;
 536         }
 537         if (devname == 0) {
 538                 fprintf(stderr, "Must specify dev.\n");
 539                 exit(-1);
 540         }
 541
 542         return tnl_prl_ioctl(cmd, medium, &p);
 543 }
 544
 545 static int do_6rd(int argc, char **argv)
 546 {
 547         struct ip_tunnel_6rd ip6rd;
 548         int devname = 0;
 549         int cmd = 0;
 550         char medium[IFNAMSIZ];
 551         inet_prefix prefix;
 552
 553         memset(&ip6rd, 0, sizeof(ip6rd));
 554         memset(&medium, 0, sizeof(medium));
 555
 556         while (argc > 0) {
 557                 if (strcmp(*argv, "6rd-prefix") == 0) {
 558                         NEXT_ARG();
 559                         if (get_prefix(&prefix, *argv, AF_INET6))
 560                                 invarg("invalid 6rd_prefix\n", *argv);
 561                         cmd = SIOCADD6RD;
 562                         memcpy(&ip6rd.prefix, prefix.data, 16);
 563                         ip6rd.prefixlen = prefix.bitlen;
 564                 } else if (strcmp(*argv, "6rd-relay_prefix") == 0) {
 565                         NEXT_ARG();
 566                         if (get_prefix(&prefix, *argv, AF_INET))
 567                                 invarg("invalid 6rd-relay_prefix\n", *argv);
 568                         cmd = SIOCADD6RD;
 569                         memcpy(&ip6rd.relay_prefix, prefix.data, 4);
 570                         ip6rd.relay_prefixlen = prefix.bitlen;
 571                 } else if (strcmp(*argv, "6rd-reset") == 0) {
 572                         cmd = SIOCDEL6RD;
 573                 } else if (strcmp(*argv, "dev") == 0) {
 574                         NEXT_ARG();
 575                         strncpy(medium, *argv, IFNAMSIZ-1);
 576                         devname++;
 577                 } else {
 578                         fprintf(stderr,"%s: Invalid 6RD parameter.\n", *argv);
 579                         exit(-1);
 580                 }
 581                 argc--; argv++;
 582         }
 583         if (devname == 0) {
 584                 fprintf(stderr, "Must specify dev.\n");
 585                 exit(-1);
 586         }
 587
 588         return tnl_6rd_ioctl(cmd, medium, &ip6rd);
 589 }
 590
 591 int do_iptunnel(int argc, char **argv)
 592 {
 593         switch (preferred_family) {
 594         case AF_UNSPEC:
 595                 preferred_family = AF_INET;
 596                 break;
 597         case AF_INET:
 598                 break;
 599         /*
 600          * This is silly enough but we have no easy way to make it
 601          * protocol-independent because of unarranged structure between
 602          * IPv4 and IPv6.
 603          */
 604         case AF_INET6:
 605                 return do_ip6tunnel(argc, argv);
 606         default:
 607                 fprintf(stderr, "Unsupported family:%d\n", preferred_family);
 608                 exit(-1);
 609         }
 610
 611         if (argc > 0) {
 612                 if (matches(*argv, "add") == 0)
 613                         return do_add(SIOCADDTUNNEL, argc-1, argv+1);
 614                 if (matches(*argv, "change") == 0)
 615                         return do_add(SIOCCHGTUNNEL, argc-1, argv+1);
 616                 if (matches(*argv, "del") == 0)
 617                         return do_del(argc-1, argv+1);
 618                 if (matches(*argv, "show") == 0 ||
 619                     matches(*argv, "lst") == 0 ||
 620                     matches(*argv, "list") == 0)
 621                         return do_show(argc-1, argv+1);
 622                 if (matches(*argv, "prl") == 0)
 623                         return do_prl(argc-1, argv+1);
 624                 if (matches(*argv, "6rd") == 0)
 625                         return do_6rd(argc-1, argv+1);
 626                 if (matches(*argv, "help") == 0)
 627                         usage();
 628         } else
 629                 return do_show(0, NULL);
 630
 631         fprintf(stderr, "Command \"%s\" is unknown, try \"ip tunnel help\".\n", *argv);
 632         exit(-1);
 633 }