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 <net/if.h>
  22 #include <net/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 = if_nametoindex(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
 310         memset(&ip6rd, 0, sizeof(ip6rd));
 311
 312         /* Do not use format_host() for local addr,
 313          * symbolic name will not be useful.
 314          */
 315         printf("%s: %s/ip  remote %s  local %s ",
 316                p->name,
 317                tnl_strproto(p->iph.protocol),
 318                p->iph.daddr ? format_host(AF_INET, 4, &p->iph.daddr, s1, sizeof(s1))  : "any",
 319                p->iph.saddr ? rt_addr_n2a(AF_INET, 4, &p->iph.saddr, s2, sizeof(s2)) : "any");
 320
 321         if (p->i_flags & SIT_ISATAP) {
 322                 struct ip_tunnel_prl prl[16];
 323                 int i;
 324
 325                 memset(prl, 0, sizeof(prl));
 326                 prl[0].datalen = sizeof(prl) - sizeof(prl[0]);
 327                 prl[0].addr = htonl(INADDR_ANY);
 328
 329                 if (!tnl_prl_ioctl(SIOCGETPRL, p->name, prl))
 330                         for (i = 1; i < sizeof(prl) / sizeof(prl[0]); i++)
 331                 {
 332                         if (prl[i].addr != htonl(INADDR_ANY)) {
 333                                 printf(" %s %s ",
 334                                         (prl[i].flags & PRL_DEFAULT) ? "pdr" : "pr",
 335                                         format_host(AF_INET, 4, &prl[i].addr, s1, sizeof(s1)));
 336                         }
 337                 }
 338         }
 339
 340         if (p->link) {
 341                 const char *n = ll_index_to_name(p->link);
 342                 if (n)
 343                         printf(" dev %s ", n);
 344         }
 345
 346         if (p->iph.ttl)
 347                 printf(" ttl %d ", p->iph.ttl);
 348         else
 349                 printf(" ttl inherit ");
 350
 351         if (p->iph.tos) {
 352                 SPRINT_BUF(b1);
 353                 printf(" tos");
 354                 if (p->iph.tos&1)
 355                         printf(" inherit");
 356                 if (p->iph.tos&~1)
 357                         printf("%c%s ", p->iph.tos&1 ? '/' : ' ',
 358                                rtnl_dsfield_n2a(p->iph.tos&~1, b1, sizeof(b1)));
 359         }
 360
 361         if (!(p->iph.frag_off&htons(IP_DF)))
 362                 printf(" nopmtudisc");
 363
 364         if (p->iph.protocol == IPPROTO_IPV6 && !tnl_ioctl_get_6rd(p->name, &ip6rd) && ip6rd.prefixlen) {
 365                 printf(" 6rd-prefix %s/%u ",
 366                        inet_ntop(AF_INET6, &ip6rd.prefix, s1, sizeof(s1)),
 367                        ip6rd.prefixlen);
 368                 if (ip6rd.relay_prefix) {
 369                         printf("6rd-relay_prefix %s/%u ",
 370                                format_host(AF_INET, 4, &ip6rd.relay_prefix, s1, sizeof(s1)),
 371                                ip6rd.relay_prefixlen);
 372                 }
 373         }
 374
 375         if ((p->i_flags&GRE_KEY) && (p->o_flags&GRE_KEY) && p->o_key == p->i_key)
 376                 printf(" key %u", ntohl(p->i_key));
 377         else if ((p->i_flags|p->o_flags)&GRE_KEY) {
 378                 if (p->i_flags&GRE_KEY)
 379                         printf(" ikey %u ", ntohl(p->i_key));
 380                 if (p->o_flags&GRE_KEY)
 381                         printf(" okey %u ", ntohl(p->o_key));
 382         }
 383
 384         if (p->i_flags&GRE_SEQ)
 385                 printf("%s  Drop packets out of sequence.\n", _SL_);
 386         if (p->i_flags&GRE_CSUM)
 387                 printf("%s  Checksum in received packet is required.", _SL_);
 388         if (p->o_flags&GRE_SEQ)
 389                 printf("%s  Sequence packets on output.", _SL_);
 390         if (p->o_flags&GRE_CSUM)
 391                 printf("%s  Checksum output packets.", _SL_);
 392 }
 393
 394 static int do_tunnels_list(struct ip_tunnel_parm *p)
 395 {
 396         char name[IFNAMSIZ];
 397         unsigned long  rx_bytes, rx_packets, rx_errs, rx_drops,
 398         rx_fifo, rx_frame,
 399         tx_bytes, tx_packets, tx_errs, tx_drops,
 400         tx_fifo, tx_colls, tx_carrier, rx_multi;
 401         struct ip_tunnel_parm p1;
 402
 403         char buf[512];
 404         FILE *fp = fopen("/proc/net/dev", "r");
 405         if (fp == NULL) {
 406                 perror("fopen");
 407                 return -1;
 408         }
 409
 410         /* skip header lines */
 411         if (!fgets(buf, sizeof(buf), fp) ||
 412             !fgets(buf, sizeof(buf), fp)) {
 413                 fprintf(stderr, "/proc/net/dev read error\n");
 414                 return -1;
 415         }
 416
 417         while (fgets(buf, sizeof(buf), fp) != NULL) {
 418                 int index, type;
 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                 index = ll_name_to_index(name);
 435                 if (index == 0)
 436                         continue;
 437                 type = ll_index_to_type(index);
 438                 if (type == -1) {
 439                         fprintf(stderr, "Failed to get type of [%s]\n", name);
 440                         continue;
 441                 }
 442                 if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT)
 443                         continue;
 444                 memset(&p1, 0, sizeof(p1));
 445                 if (tnl_get_ioctl(name, &p1))
 446                         continue;
 447                 if ((p->link && p1.link != p->link) ||
 448                     (p->name[0] && strcmp(p1.name, p->name)) ||
 449                     (p->iph.daddr && p1.iph.daddr != p->iph.daddr) ||
 450                     (p->iph.saddr && p1.iph.saddr != p->iph.saddr) ||
 451                     (p->i_key && p1.i_key != p->i_key))
 452                         continue;
 453                 print_tunnel(&p1);
 454                 if (show_stats) {
 455                         printf("%s", _SL_);
 456                         printf("RX: Packets    Bytes        Errors CsumErrs OutOfSeq Mcasts%s", _SL_);
 457                         printf("    %-10ld %-12ld %-6ld %-8ld %-8ld %-8ld%s",
 458                                rx_packets, rx_bytes, rx_errs, rx_frame, rx_fifo, rx_multi, _SL_);
 459                         printf("TX: Packets    Bytes        Errors DeadLoop NoRoute  NoBufs%s", _SL_);
 460                         printf("    %-10ld %-12ld %-6ld %-8ld %-8ld %-6ld",
 461                                tx_packets, tx_bytes, tx_errs, tx_colls, tx_carrier, tx_drops);
 462                 }
 463                 printf("\n");
 464         }
 465         return 0;
 466 }
 467
 468 static int do_show(int argc, char **argv)
 469 {
 470         int err;
 471         struct ip_tunnel_parm p;
 472
 473         ll_init_map(&rth);
 474         if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0)
 475                 return -1;
 476
 477         switch (p.iph.protocol) {
 478         case IPPROTO_IPIP:
 479                 err = tnl_get_ioctl(p.name[0] ? p.name : "tunl0", &p);
 480                 break;
 481         case IPPROTO_GRE:
 482                 err = tnl_get_ioctl(p.name[0] ? p.name : "gre0", &p);
 483                 break;
 484         case IPPROTO_IPV6:
 485                 err = tnl_get_ioctl(p.name[0] ? p.name : "sit0", &p);
 486                 break;
 487         default:
 488                 do_tunnels_list(&p);
 489                 return 0;
 490         }
 491         if (err)
 492                 return -1;
 493
 494         print_tunnel(&p);
 495         printf("\n");
 496         return 0;
 497 }
 498
 499 static int do_prl(int argc, char **argv)
 500 {
 501         struct ip_tunnel_prl p;
 502         int count = 0;
 503         int devname = 0;
 504         int cmd = 0;
 505         char medium[IFNAMSIZ];
 506
 507         memset(&p, 0, sizeof(p));
 508         memset(&medium, 0, sizeof(medium));
 509
 510         while (argc > 0) {
 511                 if (strcmp(*argv, "prl-default") == 0) {
 512                         NEXT_ARG();
 513                         cmd = SIOCADDPRL;
 514                         p.addr = get_addr32(*argv);
 515                         p.flags |= PRL_DEFAULT;
 516                         count++;
 517                 } else if (strcmp(*argv, "prl-nodefault") == 0) {
 518                         NEXT_ARG();
 519                         cmd = SIOCADDPRL;
 520                         p.addr = get_addr32(*argv);
 521                         count++;
 522                 } else if (strcmp(*argv, "prl-delete") == 0) {
 523                         NEXT_ARG();
 524                         cmd = SIOCDELPRL;
 525                         p.addr = get_addr32(*argv);
 526                         count++;
 527                 } else if (strcmp(*argv, "dev") == 0) {
 528                         NEXT_ARG();
 529                         strncpy(medium, *argv, IFNAMSIZ-1);
 530                         devname++;
 531                 } else {
 532                         fprintf(stderr,"%s: Invalid PRL parameter.\n", *argv);
 533                         exit(-1);
 534                 }
 535                 if (count > 1) {
 536                         fprintf(stderr,"One PRL entry at a time.\n");
 537                         exit(-1);
 538                 }
 539                 argc--; argv++;
 540         }
 541         if (devname == 0) {
 542                 fprintf(stderr, "Must specify dev.\n");
 543                 exit(-1);
 544         }
 545
 546         return tnl_prl_ioctl(cmd, medium, &p);
 547 }
 548
 549 static int do_6rd(int argc, char **argv)
 550 {
 551         struct ip_tunnel_6rd ip6rd;
 552         int devname = 0;
 553         int cmd = 0;
 554         char medium[IFNAMSIZ];
 555         inet_prefix prefix;
 556
 557         memset(&ip6rd, 0, sizeof(ip6rd));
 558         memset(&medium, 0, sizeof(medium));
 559
 560         while (argc > 0) {
 561                 if (strcmp(*argv, "6rd-prefix") == 0) {
 562                         NEXT_ARG();
 563                         if (get_prefix(&prefix, *argv, AF_INET6))
 564                                 invarg("invalid 6rd_prefix\n", *argv);
 565                         cmd = SIOCADD6RD;
 566                         memcpy(&ip6rd.prefix, prefix.data, 16);
 567                         ip6rd.prefixlen = prefix.bitlen;
 568                 } else if (strcmp(*argv, "6rd-relay_prefix") == 0) {
 569                         NEXT_ARG();
 570                         if (get_prefix(&prefix, *argv, AF_INET))
 571                                 invarg("invalid 6rd-relay_prefix\n", *argv);
 572                         cmd = SIOCADD6RD;
 573                         memcpy(&ip6rd.relay_prefix, prefix.data, 4);
 574                         ip6rd.relay_prefixlen = prefix.bitlen;
 575                 } else if (strcmp(*argv, "6rd-reset") == 0) {
 576                         cmd = SIOCDEL6RD;
 577                 } else if (strcmp(*argv, "dev") == 0) {
 578                         NEXT_ARG();
 579                         strncpy(medium, *argv, IFNAMSIZ-1);
 580                         devname++;
 581                 } else {
 582                         fprintf(stderr,"%s: Invalid 6RD parameter.\n", *argv);
 583                         exit(-1);
 584                 }
 585                 argc--; argv++;
 586         }
 587         if (devname == 0) {
 588                 fprintf(stderr, "Must specify dev.\n");
 589                 exit(-1);
 590         }
 591
 592         return tnl_6rd_ioctl(cmd, medium, &ip6rd);
 593 }
 594
 595 int do_iptunnel(int argc, char **argv)
 596 {
 597         switch (preferred_family) {
 598         case AF_UNSPEC:
 599                 preferred_family = AF_INET;
 600                 break;
 601         case AF_INET:
 602                 break;
 603         /*
 604          * This is silly enough but we have no easy way to make it
 605          * protocol-independent because of unarranged structure between
 606          * IPv4 and IPv6.
 607          */
 608         case AF_INET6:
 609                 return do_ip6tunnel(argc, argv);
 610         default:
 611                 fprintf(stderr, "Unsupported family:%d\n", preferred_family);
 612                 exit(-1);
 613         }
 614
 615         if (argc > 0) {
 616                 if (matches(*argv, "add") == 0)
 617                         return do_add(SIOCADDTUNNEL, argc-1, argv+1);
 618                 if (matches(*argv, "change") == 0)
 619                         return do_add(SIOCCHGTUNNEL, argc-1, argv+1);
 620                 if (matches(*argv, "del") == 0)
 621                         return do_del(argc-1, argv+1);
 622                 if (matches(*argv, "show") == 0 ||
 623                     matches(*argv, "lst") == 0 ||
 624                     matches(*argv, "list") == 0)
 625                         return do_show(argc-1, argv+1);
 626                 if (matches(*argv, "prl") == 0)
 627                         return do_prl(argc-1, argv+1);
 628                 if (matches(*argv, "6rd") == 0)
 629                         return do_6rd(argc-1, argv+1);
 630                 if (matches(*argv, "help") == 0)
 631                         usage();
 632         } else
 633                 return do_show(0, NULL);
 634
 635         fprintf(stderr, "Command \"%s\" is unknown, try \"ip tunnel help\".\n", *argv);
 636         exit(-1);
 637 }