networking/libiproute/iptunnel.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   4  *
   5  * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   6  *
   7  * Changes:
   8  *
   9  * Rani Assaf <rani@magic.metawire.com> 980929: resolve addresses
  10  * Rani Assaf <rani@magic.metawire.com> 980930: do not allow key for ipip/sit
  11  * Phil Karn <karn@ka9q.ampr.org>       990408: "pmtudisc" flag
  12  */
  13 #include <netinet/ip.h>
  14 #include <net/if.h>
  15 #include <net/if_arp.h>
  16 #include <asm/types.h>
  17
  18 #ifndef __constant_htons
  19 #define __constant_htons htons
  20 #endif
  21
  22 // FYI: #define SIOCDEVPRIVATE 0x89F0
  23
  24 /* From linux/if_tunnel.h. #including it proved troublesome
  25  * (redefiniton errors due to name collisions in linux/ and net[inet]/) */
  26 #define SIOCGETTUNNEL   (SIOCDEVPRIVATE + 0)
  27 #define SIOCADDTUNNEL   (SIOCDEVPRIVATE + 1)
  28 #define SIOCDELTUNNEL   (SIOCDEVPRIVATE + 2)
  29 #define SIOCCHGTUNNEL   (SIOCDEVPRIVATE + 3)
  30 //#define SIOCGETPRL      (SIOCDEVPRIVATE + 4)
  31 //#define SIOCADDPRL      (SIOCDEVPRIVATE + 5)
  32 //#define SIOCDELPRL      (SIOCDEVPRIVATE + 6)
  33 //#define SIOCCHGPRL      (SIOCDEVPRIVATE + 7)
  34 #define GRE_CSUM        __constant_htons(0x8000)
  35 //#define GRE_ROUTING     __constant_htons(0x4000)
  36 #define GRE_KEY         __constant_htons(0x2000)
  37 #define GRE_SEQ         __constant_htons(0x1000)
  38 //#define GRE_STRICT      __constant_htons(0x0800)
  39 //#define GRE_REC         __constant_htons(0x0700)
  40 //#define GRE_FLAGS       __constant_htons(0x00F8)
  41 //#define GRE_VERSION     __constant_htons(0x0007)
  42 struct ip_tunnel_parm {
  43         char            name[IFNAMSIZ];
  44         int             link;
  45         uint16_t        i_flags;
  46         uint16_t        o_flags;
  47         uint32_t        i_key;
  48         uint32_t        o_key;
  49         struct iphdr    iph;
  50 };
  51 /* SIT-mode i_flags */
  52 //#define SIT_ISATAP 0x0001
  53 //struct ip_tunnel_prl {
  54 //      uint32_t          addr;
  55 //      uint16_t          flags;
  56 //      uint16_t          __reserved;
  57 //      uint32_t          datalen;
  58 //      uint32_t          __reserved2;
  59 //      /* data follows */
  60 //};
  61 ///* PRL flags */
  62 //#define PRL_DEFAULT 0x0001
  63
  64 #include "ip_common.h"  /* #include "libbb.h" is inside */
  65 #include "rt_names.h"
  66 #include "utils.h"
  67
  68
  69 /* Dies on error */
  70 static int do_ioctl_get_ifindex(char *dev)
  71 {
  72         struct ifreq ifr;
  73         int fd;
  74
  75         strncpy_IFNAMSIZ(ifr.ifr_name, dev);
  76         fd = xsocket(AF_INET, SOCK_DGRAM, 0);
  77         xioctl(fd, SIOCGIFINDEX, &ifr);
  78         close(fd);
  79         return ifr.ifr_ifindex;
  80 }
  81
  82 static int do_ioctl_get_iftype(char *dev)
  83 {
  84         struct ifreq ifr;
  85         int fd;
  86         int err;
  87
  88         strncpy_IFNAMSIZ(ifr.ifr_name, dev);
  89         fd = xsocket(AF_INET, SOCK_DGRAM, 0);
  90         err = ioctl_or_warn(fd, SIOCGIFHWADDR, &ifr);
  91         close(fd);
  92         return err ? -1 : ifr.ifr_addr.sa_family;
  93 }
  94
  95 static char *do_ioctl_get_ifname(int idx)
  96 {
  97         struct ifreq ifr;
  98         int fd;
  99         int err;
 100
 101         ifr.ifr_ifindex = idx;
 102         fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 103         err = ioctl_or_warn(fd, SIOCGIFNAME, &ifr);
 104         close(fd);
 105         return err ? NULL : xstrndup(ifr.ifr_name, sizeof(ifr.ifr_name));
 106 }
 107
 108 static int do_get_ioctl(const char *basedev, struct ip_tunnel_parm *p)
 109 {
 110         struct ifreq ifr;
 111         int fd;
 112         int err;
 113
 114         strncpy_IFNAMSIZ(ifr.ifr_name, basedev);
 115         ifr.ifr_ifru.ifru_data = (void*)p;
 116         fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 117         err = ioctl_or_warn(fd, SIOCGETTUNNEL, &ifr);
 118         close(fd);
 119         return err;
 120 }
 121
 122 /* Dies on error, otherwise returns 0 */
 123 static int do_add_ioctl(int cmd, const char *basedev, struct ip_tunnel_parm *p)
 124 {
 125         struct ifreq ifr;
 126         int fd;
 127
 128         if (cmd == SIOCCHGTUNNEL && p->name[0]) {
 129                 strncpy_IFNAMSIZ(ifr.ifr_name, p->name);
 130         } else {
 131                 strncpy_IFNAMSIZ(ifr.ifr_name, basedev);
 132         }
 133         ifr.ifr_ifru.ifru_data = (void*)p;
 134         fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 135 #if ENABLE_IOCTL_HEX2STR_ERROR
 136         /* #define magic will turn ioctl# into string */
 137         if (cmd == SIOCCHGTUNNEL)
 138                 xioctl(fd, SIOCCHGTUNNEL, &ifr);
 139         else
 140                 xioctl(fd, SIOCADDTUNNEL, &ifr);
 141 #else
 142         xioctl(fd, cmd, &ifr);
 143 #endif
 144         close(fd);
 145         return 0;
 146 }
 147
 148 /* Dies on error, otherwise returns 0 */
 149 static int do_del_ioctl(const char *basedev, struct ip_tunnel_parm *p)
 150 {
 151         struct ifreq ifr;
 152         int fd;
 153
 154         if (p->name[0]) {
 155                 strncpy_IFNAMSIZ(ifr.ifr_name, p->name);
 156         } else {
 157                 strncpy_IFNAMSIZ(ifr.ifr_name, basedev);
 158         }
 159         ifr.ifr_ifru.ifru_data = (void*)p;
 160         fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 161         xioctl(fd, SIOCDELTUNNEL, &ifr);
 162         close(fd);
 163         return 0;
 164 }
 165
 166 /* Dies on error */
 167 static void parse_args(char **argv, int cmd, struct ip_tunnel_parm *p)
 168 {
 169         static const char keywords[] ALIGN1 =
 170                 "mode\0""ipip\0""ip/ip\0""gre\0""gre/ip\0""sit\0""ipv6/ip\0"
 171                 "key\0""ikey\0""okey\0""seq\0""iseq\0""oseq\0"
 172                 "csum\0""icsum\0""ocsum\0""nopmtudisc\0""pmtudisc\0"
 173                 "remote\0""any\0""local\0""dev\0"
 174                 "ttl\0""inherit\0""tos\0""dsfield\0"
 175                 "name\0";
 176         enum {
 177                 ARG_mode, ARG_ipip, ARG_ip_ip, ARG_gre, ARG_gre_ip, ARG_sit, ARG_ip6_ip,
 178                 ARG_key, ARG_ikey, ARG_okey, ARG_seq, ARG_iseq, ARG_oseq,
 179                 ARG_csum, ARG_icsum, ARG_ocsum, ARG_nopmtudisc, ARG_pmtudisc,
 180                 ARG_remote, ARG_any, ARG_local, ARG_dev,
 181                 ARG_ttl, ARG_inherit, ARG_tos, ARG_dsfield,
 182                 ARG_name
 183         };
 184         int count = 0;
 185         char medium[IFNAMSIZ];
 186         int key;
 187
 188         memset(p, 0, sizeof(*p));
 189         medium[0] = '\0';
 190
 191         p->iph.version = 4;
 192         p->iph.ihl = 5;
 193 #ifndef IP_DF
 194 #define IP_DF 0x4000  /* Flag: "Don't Fragment" */
 195 #endif
 196         p->iph.frag_off = htons(IP_DF);
 197
 198         while (*argv) {
 199                 key = index_in_strings(keywords, *argv);
 200                 if (key == ARG_mode) {
 201                         NEXT_ARG();
 202                         key = index_in_strings(keywords, *argv);
 203                         if (key == ARG_ipip ||
 204                             key == ARG_ip_ip
 205                         ) {
 206                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_IPIP) {
 207                                         bb_error_msg_and_die("%s tunnel mode", "you managed to ask for more than one");
 208                                 }
 209                                 p->iph.protocol = IPPROTO_IPIP;
 210                         } else if (key == ARG_gre ||
 211                                    key == ARG_gre_ip
 212                         ) {
 213                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_GRE) {
 214                                         bb_error_msg_and_die("%s tunnel mode", "you managed to ask for more than one");
 215                                 }
 216                                 p->iph.protocol = IPPROTO_GRE;
 217                         } else if (key == ARG_sit ||
 218                                    key == ARG_ip6_ip
 219                         ) {
 220                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_IPV6) {
 221                                         bb_error_msg_and_die("%s tunnel mode", "you managed to ask for more than one");
 222                                 }
 223                                 p->iph.protocol = IPPROTO_IPV6;
 224                         } else {
 225                                 bb_error_msg_and_die("%s tunnel mode", "can't guess");
 226                         }
 227                 } else if (key == ARG_key) {
 228                         unsigned uval;
 229                         NEXT_ARG();
 230                         p->i_flags |= GRE_KEY;
 231                         p->o_flags |= GRE_KEY;
 232                         if (strchr(*argv, '.'))
 233                                 p->i_key = p->o_key = get_addr32(*argv);
 234                         else {
 235                                 uval = get_unsigned(*argv, "key");
 236                                 p->i_key = p->o_key = htonl(uval);
 237                         }
 238                 } else if (key == ARG_ikey) {
 239                         unsigned uval;
 240                         NEXT_ARG();
 241                         p->i_flags |= GRE_KEY;
 242                         if (strchr(*argv, '.'))
 243                                 p->o_key = get_addr32(*argv);
 244                         else {
 245                                 uval = get_unsigned(*argv, "ikey");
 246                                 p->i_key = htonl(uval);
 247                         }
 248                 } else if (key == ARG_okey) {
 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                                 uval = get_unsigned(*argv, "okey");
 256                                 p->o_key = htonl(uval);
 257                         }
 258                 } else if (key == ARG_seq) {
 259                         p->i_flags |= GRE_SEQ;
 260                         p->o_flags |= GRE_SEQ;
 261                 } else if (key == ARG_iseq) {
 262                         p->i_flags |= GRE_SEQ;
 263                 } else if (key == ARG_oseq) {
 264                         p->o_flags |= GRE_SEQ;
 265                 } else if (key == ARG_csum) {
 266                         p->i_flags |= GRE_CSUM;
 267                         p->o_flags |= GRE_CSUM;
 268                 } else if (key == ARG_icsum) {
 269                         p->i_flags |= GRE_CSUM;
 270                 } else if (key == ARG_ocsum) {
 271                         p->o_flags |= GRE_CSUM;
 272                 } else if (key == ARG_nopmtudisc) {
 273                         p->iph.frag_off = 0;
 274                 } else if (key == ARG_pmtudisc) {
 275                         p->iph.frag_off = htons(IP_DF);
 276                 } else if (key == ARG_remote) {
 277                         NEXT_ARG();
 278                         key = index_in_strings(keywords, *argv);
 279                         if (key != ARG_any)
 280                                 p->iph.daddr = get_addr32(*argv);
 281                 } else if (key == ARG_local) {
 282                         NEXT_ARG();
 283                         key = index_in_strings(keywords, *argv);
 284                         if (key != ARG_any)
 285                                 p->iph.saddr = get_addr32(*argv);
 286                 } else if (key == ARG_dev) {
 287                         NEXT_ARG();
 288                         strncpy_IFNAMSIZ(medium, *argv);
 289                 } else if (key == ARG_ttl) {
 290                         unsigned uval;
 291                         NEXT_ARG();
 292                         key = index_in_strings(keywords, *argv);
 293                         if (key != ARG_inherit) {
 294                                 uval = get_unsigned(*argv, "TTL");
 295                                 if (uval > 255)
 296                                         invarg_1_to_2(*argv, "TTL");
 297                                 p->iph.ttl = uval;
 298                         }
 299                 } else if (key == ARG_tos ||
 300                            key == ARG_dsfield
 301                 ) {
 302                         uint32_t uval;
 303                         NEXT_ARG();
 304                         key = index_in_strings(keywords, *argv);
 305                         if (key != ARG_inherit) {
 306                                 if (rtnl_dsfield_a2n(&uval, *argv))
 307                                         invarg_1_to_2(*argv, "TOS");
 308                                 p->iph.tos = uval;
 309                         } else
 310                                 p->iph.tos = 1;
 311                 } else {
 312                         if (key == ARG_name) {
 313                                 NEXT_ARG();
 314                         }
 315                         if (p->name[0])
 316                                 duparg2("name", *argv);
 317                         strncpy_IFNAMSIZ(p->name, *argv);
 318                         if (cmd == SIOCCHGTUNNEL && count == 0) {
 319                                 struct ip_tunnel_parm old_p;
 320                                 memset(&old_p, 0, sizeof(old_p));
 321                                 if (do_get_ioctl(*argv, &old_p))
 322                                         exit_FAILURE();
 323                                 *p = old_p;
 324                         }
 325                 }
 326                 count++;
 327                 argv++;
 328         }
 329
 330         if (p->iph.protocol == 0) {
 331                 if (memcmp(p->name, "gre", 3) == 0)
 332                         p->iph.protocol = IPPROTO_GRE;
 333                 else if (memcmp(p->name, "ipip", 4) == 0)
 334                         p->iph.protocol = IPPROTO_IPIP;
 335                 else if (memcmp(p->name, "sit", 3) == 0)
 336                         p->iph.protocol = IPPROTO_IPV6;
 337         }
 338
 339         if (p->iph.protocol == IPPROTO_IPIP || p->iph.protocol == IPPROTO_IPV6) {
 340                 if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) {
 341                         bb_simple_error_msg_and_die("keys are not allowed with ipip and sit");
 342                 }
 343         }
 344
 345         if (medium[0]) {
 346                 p->link = do_ioctl_get_ifindex(medium);
 347         }
 348
 349         if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
 350                 p->i_key = p->iph.daddr;
 351                 p->i_flags |= GRE_KEY;
 352         }
 353         if (p->o_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
 354                 p->o_key = p->iph.daddr;
 355                 p->o_flags |= GRE_KEY;
 356         }
 357         if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) {
 358                 bb_simple_error_msg_and_die("broadcast tunnel requires a source address");
 359         }
 360 }
 361
 362 /* Return value becomes exitcode. It's okay to not return at all */
 363 static int do_add(int cmd, char **argv)
 364 {
 365         struct ip_tunnel_parm p;
 366
 367         parse_args(argv, cmd, &p);
 368
 369         if (p.iph.ttl && p.iph.frag_off == 0) {
 370                 bb_simple_error_msg_and_die("ttl != 0 and noptmudisc are incompatible");
 371         }
 372
 373         switch (p.iph.protocol) {
 374         case IPPROTO_IPIP:
 375                 return do_add_ioctl(cmd, "tunl0", &p);
 376         case IPPROTO_GRE:
 377                 return do_add_ioctl(cmd, "gre0", &p);
 378         case IPPROTO_IPV6:
 379                 return do_add_ioctl(cmd, "sit0", &p);
 380         default:
 381                 bb_simple_error_msg_and_die("can't determine tunnel mode (ipip, gre or sit)");
 382         }
 383 }
 384
 385 /* Return value becomes exitcode. It's okay to not return at all */
 386 static int do_del(char **argv)
 387 {
 388         struct ip_tunnel_parm p;
 389
 390         parse_args(argv, SIOCDELTUNNEL, &p);
 391
 392         switch (p.iph.protocol) {
 393         case IPPROTO_IPIP:
 394                 return do_del_ioctl("tunl0", &p);
 395         case IPPROTO_GRE:
 396                 return do_del_ioctl("gre0", &p);
 397         case IPPROTO_IPV6:
 398                 return do_del_ioctl("sit0", &p);
 399         default:
 400                 return do_del_ioctl(p.name, &p);
 401         }
 402 }
 403
 404 static void print_tunnel(struct ip_tunnel_parm *p)
 405 {
 406         char s3[INET_ADDRSTRLEN];
 407         char s4[INET_ADDRSTRLEN];
 408
 409         printf("%s: %s/ip  remote %s  local %s ",
 410                 p->name,
 411                 p->iph.protocol == IPPROTO_IPIP ? "ip" :
 412                         p->iph.protocol == IPPROTO_GRE ? "gre" :
 413                         p->iph.protocol == IPPROTO_IPV6 ? "ipv6" :
 414                         "unknown",
 415                 p->iph.daddr ? format_host(AF_INET, 4, &p->iph.daddr) : "any",
 416                 p->iph.saddr ? format_host(AF_INET, 4, &p->iph.saddr) : "any"
 417         );
 418         if (p->link) {
 419                 char *n = do_ioctl_get_ifname(p->link);
 420                 if (n) {
 421                         printf(" dev %s ", n);
 422                         free(n);
 423                 }
 424         }
 425         if (p->iph.ttl)
 426                 printf(" ttl %d ", p->iph.ttl);
 427         else
 428                 printf(" ttl inherit ");
 429         if (p->iph.tos) {
 430                 printf(" tos");
 431                 if (p->iph.tos & 1)
 432                         printf(" inherit");
 433                 if (p->iph.tos & ~1)
 434                         printf("%c%s ", p->iph.tos & 1 ? '/' : ' ',
 435                                 rtnl_dsfield_n2a(p->iph.tos & ~1));
 436         }
 437         if (!(p->iph.frag_off & htons(IP_DF)))
 438                 printf(" nopmtudisc");
 439
 440         inet_ntop(AF_INET, &p->i_key, s3, sizeof(s3));
 441         inet_ntop(AF_INET, &p->o_key, s4, sizeof(s4));
 442         if ((p->i_flags & GRE_KEY) && (p->o_flags & GRE_KEY) && p->o_key == p->i_key)
 443                 printf(" key %s", s3);
 444         else {
 445                 if (p->i_flags & GRE_KEY)
 446                         printf(" ikey %s ", s3);
 447                 if (p->o_flags & GRE_KEY)
 448                         printf(" okey %s ", s4);
 449         }
 450
 451         if (p->i_flags & GRE_SEQ)
 452                 printf("%c  Drop packets out of sequence.\n", _SL_);
 453         if (p->i_flags & GRE_CSUM)
 454                 printf("%c  Checksum in received packet is required.", _SL_);
 455         if (p->o_flags & GRE_SEQ)
 456                 printf("%c  Sequence packets on output.", _SL_);
 457         if (p->o_flags & GRE_CSUM)
 458                 printf("%c  Checksum output packets.", _SL_);
 459 }
 460
 461 static void do_tunnels_list(struct ip_tunnel_parm *p)
 462 {
 463         char name[IFNAMSIZ];
 464         unsigned long rx_bytes, rx_packets, rx_errs, rx_drops,
 465                 rx_fifo, rx_frame,
 466                 tx_bytes, tx_packets, tx_errs, tx_drops,
 467                 tx_fifo, tx_colls, tx_carrier, rx_multi;
 468         int type;
 469         struct ip_tunnel_parm p1;
 470         char buf[512];
 471         FILE *fp = fopen_or_warn("/proc/net/dev", "r");
 472
 473         if (fp == NULL) {
 474                 return;
 475         }
 476         /* skip headers */
 477         fgets(buf, sizeof(buf), fp);
 478         fgets(buf, sizeof(buf), fp);
 479
 480         while (fgets(buf, sizeof(buf), fp) != NULL) {
 481                 char *ptr;
 482
 483                 /*buf[sizeof(buf) - 1] = 0; - fgets is safe anyway */
 484                 ptr = strchr(buf, ':');
 485                 if (ptr == NULL ||
 486                     (*ptr++ = 0, sscanf(buf, "%s", name) != 1)
 487                 ) {
 488                         bb_simple_error_msg("wrong format of /proc/net/dev");
 489                         return;
 490                 }
 491                 if (sscanf(ptr, "%lu%lu%lu%lu%lu%lu%lu%*d%lu%lu%lu%lu%lu%lu%lu",
 492                            &rx_bytes, &rx_packets, &rx_errs, &rx_drops,
 493                            &rx_fifo, &rx_frame, &rx_multi,
 494                            &tx_bytes, &tx_packets, &tx_errs, &tx_drops,
 495                            &tx_fifo, &tx_colls, &tx_carrier) != 14)
 496                         continue;
 497                 if (p->name[0] && strcmp(p->name, name))
 498                         continue;
 499                 type = do_ioctl_get_iftype(name);
 500                 if (type == -1) {
 501                         bb_error_msg("can't get type of [%s]", name);
 502                         continue;
 503                 }
 504                 if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT)
 505                         continue;
 506                 memset(&p1, 0, sizeof(p1));
 507                 if (do_get_ioctl(name, &p1))
 508                         continue;
 509                 if ((p->link && p1.link != p->link) ||
 510                     (p->name[0] && strcmp(p1.name, p->name)) ||
 511                     (p->iph.daddr && p1.iph.daddr != p->iph.daddr) ||
 512                     (p->iph.saddr && p1.iph.saddr != p->iph.saddr) ||
 513                     (p->i_key && p1.i_key != p->i_key)
 514                 ) {
 515                         continue;
 516                 }
 517                 print_tunnel(&p1);
 518                 bb_putchar('\n');
 519         }
 520 }
 521
 522 /* Return value becomes exitcode. It's okay to not return at all */
 523 static int do_show(char **argv)
 524 {
 525         int err;
 526         struct ip_tunnel_parm p;
 527
 528         parse_args(argv, SIOCGETTUNNEL, &p);
 529
 530         switch (p.iph.protocol) {
 531         case IPPROTO_IPIP:
 532                 err = do_get_ioctl(p.name[0] ? p.name : "tunl0", &p);
 533                 break;
 534         case IPPROTO_GRE:
 535                 err = do_get_ioctl(p.name[0] ? p.name : "gre0", &p);
 536                 break;
 537         case IPPROTO_IPV6:
 538                 err = do_get_ioctl(p.name[0] ? p.name : "sit0", &p);
 539                 break;
 540         default:
 541                 do_tunnels_list(&p);
 542                 return 0;
 543         }
 544         if (err)
 545                 return -1;
 546
 547         print_tunnel(&p);
 548         bb_putchar('\n');
 549         return 0;
 550 }
 551
 552 /* Return value becomes exitcode. It's okay to not return at all */
 553 int FAST_FUNC do_iptunnel(char **argv)
 554 {
 555         static const char keywords[] ALIGN1 =
 556                 "add\0""change\0""delete\0""show\0""list\0""lst\0";
 557         enum { ARG_add = 0, ARG_change, ARG_del, ARG_show, ARG_list, ARG_lst };
 558
 559         if (*argv) {
 560                 int key = index_in_substrings(keywords, *argv);
 561                 if (key < 0)
 562                         invarg_1_to_2(*argv, applet_name);
 563                 argv++;
 564                 if (key == ARG_add)
 565                         return do_add(SIOCADDTUNNEL, argv);
 566                 if (key == ARG_change)
 567                         return do_add(SIOCCHGTUNNEL, argv);
 568                 if (key == ARG_del)
 569                         return do_del(argv);
 570         }
 571         return do_show(argv);
 572 }