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  * 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  * Phil Karn <karn@ka9q.ampr.org>       990408: "pmtudisc" flag
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <unistd.h>
  23 #include <sys/types.h>
  24 #include <sys/socket.h>
  25 #include <arpa/inet.h>
  26 #include <sys/ioctl.h>
  27 #include <linux/if.h>
  28 #include <linux/if_arp.h>
  29 #include <linux/ip.h>
  30 #include <linux/if_tunnel.h>
  31
  32 #include "rt_names.h"
  33 #include "utils.h"
  34 #include "ip_common.h"
  35 #include "tunnel.h"
  36
  37 #define ETH_P_ETH       0x6558          /* Ethernet in Ethernet         */
  38
  39
  40 static void usage(void) __attribute__((noreturn));
  41
  42 static void usage(void)
  43 {
  44         fprintf(stderr, "Usage: ip tunnel { add | change | del | show } [ NAME ]\n");
  45     fprintf(stderr, "          [ mode { ipip | gre [ type { ip | eth } ]| sit } ] [ remote ADDR ] [ local ADDR ]\n");
  46         fprintf(stderr, "          [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n");
  47         fprintf(stderr, "          [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [ dev PHYS_DEV ]\n");
  48         fprintf(stderr, "\n");
  49         fprintf(stderr, "Where: NAME := STRING\n");
  50         fprintf(stderr, "       ADDR := { IP_ADDRESS | any }\n");
  51         fprintf(stderr, "       TOS  := { NUMBER | inherit }\n");
  52         fprintf(stderr, "       TTL  := { 1..255 | inherit }\n");
  53         fprintf(stderr, "       KEY  := { DOTTED_QUAD | NUMBER }\n");
  54         exit(-1);
  55 }
  56
  57 static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
  58 {
  59         int count = 0;
  60         char medium[IFNAMSIZ];
  61         int isatap = 0;
  62
  63         memset(p, 0, sizeof(*p));
  64         memset(&medium, 0, sizeof(medium));
  65
  66         p->iph.version = 4;
  67         p->iph.ihl = 5;
  68 #ifndef IP_DF
  69 #define IP_DF           0x4000          /* Flag: "Don't Fragment"       */
  70 #endif
  71         p->iph.frag_off = htons(IP_DF);
  72
  73         while (argc > 0) {
  74                 if (strcmp(*argv, "mode") == 0) {
  75                         NEXT_ARG();
  76                         if (strcmp(*argv, "ipip") == 0 ||
  77                             strcmp(*argv, "ip/ip") == 0) {
  78                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_IPIP) {
  79                                         fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
  80                                         exit(-1);
  81                                 }
  82                                 p->iph.protocol = IPPROTO_IPIP;
  83                         } else if (strcmp(*argv, "gre") == 0 ||
  84                                    strcmp(*argv, "gre/ip") == 0) {
  85                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_GRE) {
  86                                         fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
  87                                         exit(-1);
  88                                 }
  89                                 p->iph.protocol = IPPROTO_GRE;
  90                 NEXT_ARG();
  91                 if (strcmp(*argv,"type") == 0)
  92                 {
  93                     NEXT_ARG();
  94                     printf("90 route %s\n", *argv);
  95                     if (strcmp(*argv,"eth") == 0)
  96                     {
  97                     p->proto_type = ETH_P_ETH;
  98                     }
  99                     else
 100                     {
 101                     p->proto_type = ETH_P_IP;
 102                     }
 103                 }
 104                         } else if (strcmp(*argv, "sit") == 0 ||
 105                                    strcmp(*argv, "ipv6/ip") == 0) {
 106                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_IPV6) {
 107                                         fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
 108                                         exit(-1);
 109                                 }
 110                                 p->iph.protocol = IPPROTO_IPV6;
 111                         } else if (strcmp(*argv, "isatap") == 0) {
 112                                 if (p->iph.protocol && p->iph.protocol != IPPROTO_IPV6) {
 113                                         fprintf(stderr, "You managed to ask for more than one tunnel mode.\n");
 114                                         exit(-1);
 115                                 }
 116                                 p->iph.protocol = IPPROTO_IPV6;
 117                                 isatap++;
 118                         } else {
 119                                 fprintf(stderr,"Cannot guess tunnel mode.\n");
 120                                 exit(-1);
 121                         }
 122                 } else if (strcmp(*argv, "key") == 0) {
 123                         unsigned uval;
 124                         NEXT_ARG();
 125                         p->i_flags |= GRE_KEY;
 126                         p->o_flags |= GRE_KEY;
 127                         if (strchr(*argv, '.'))
 128                                 p->i_key = p->o_key = get_addr32(*argv);
 129                         else {
 130                                 if (get_unsigned(&uval, *argv, 0)<0) {
 131                                         fprintf(stderr, "invalid value of \"key\"\n");
 132                                         exit(-1);
 133                                 }
 134                                 p->i_key = p->o_key = htonl(uval);
 135                         }
 136                 } else if (strcmp(*argv, "ikey") == 0) {
 137                         unsigned uval;
 138                         NEXT_ARG();
 139                         p->i_flags |= GRE_KEY;
 140                         if (strchr(*argv, '.'))
 141                                 p->i_key = get_addr32(*argv);
 142                         else {
 143                                 if (get_unsigned(&uval, *argv, 0)<0) {
 144                                         fprintf(stderr, "invalid value of \"ikey\"\n");
 145                                         exit(-1);
 146                                 }
 147                                 p->i_key = htonl(uval);
 148                         }
 149                 } else if (strcmp(*argv, "okey") == 0) {
 150                         unsigned uval;
 151                         NEXT_ARG();
 152                         p->o_flags |= GRE_KEY;
 153                         if (strchr(*argv, '.'))
 154                                 p->o_key = get_addr32(*argv);
 155                         else {
 156                                 if (get_unsigned(&uval, *argv, 0)<0) {
 157                                         fprintf(stderr, "invalid value of \"okey\"\n");
 158                                         exit(-1);
 159                                 }
 160                                 p->o_key = htonl(uval);
 161                         }
 162                 } else if (strcmp(*argv, "seq") == 0) {
 163                         p->i_flags |= GRE_SEQ;
 164                         p->o_flags |= GRE_SEQ;
 165                 } else if (strcmp(*argv, "iseq") == 0) {
 166                         p->i_flags |= GRE_SEQ;
 167                 } else if (strcmp(*argv, "oseq") == 0) {
 168                         p->o_flags |= GRE_SEQ;
 169                 } else if (strcmp(*argv, "csum") == 0) {
 170                         p->i_flags |= GRE_CSUM;
 171                         p->o_flags |= GRE_CSUM;
 172                 } else if (strcmp(*argv, "icsum") == 0) {
 173                         p->i_flags |= GRE_CSUM;
 174                 } else if (strcmp(*argv, "ocsum") == 0) {
 175                         p->o_flags |= GRE_CSUM;
 176                 } else if (strcmp(*argv, "nopmtudisc") == 0) {
 177                         p->iph.frag_off = 0;
 178                 } else if (strcmp(*argv, "pmtudisc") == 0) {
 179                         p->iph.frag_off = htons(IP_DF);
 180                 } else if (strcmp(*argv, "remote") == 0) {
 181                         NEXT_ARG();
 182                         if (strcmp(*argv, "any"))
 183                                 p->iph.daddr = get_addr32(*argv);
 184                 } else if (strcmp(*argv, "local") == 0) {
 185                         NEXT_ARG();
 186                         if (strcmp(*argv, "any"))
 187                                 p->iph.saddr = get_addr32(*argv);
 188                 } else if (strcmp(*argv, "dev") == 0) {
 189                         NEXT_ARG();
 190                         strncpy(medium, *argv, IFNAMSIZ-1);
 191                 } else if (strcmp(*argv, "ttl") == 0 ||
 192                            strcmp(*argv, "hoplimit") == 0) {
 193                         unsigned uval;
 194                         NEXT_ARG();
 195                         if (strcmp(*argv, "inherit") != 0) {
 196                                 if (get_unsigned(&uval, *argv, 0))
 197                                         invarg("invalid TTL\n", *argv);
 198                                 if (uval > 255)
 199                                         invarg("TTL must be <=255\n", *argv);
 200                                 p->iph.ttl = uval;
 201                         }
 202                 } else if (strcmp(*argv, "tos") == 0 ||
 203                            strcmp(*argv, "tclass") == 0 ||
 204                            matches(*argv, "dsfield") == 0) {
 205                         __u32 uval;
 206                         NEXT_ARG();
 207                         if (strcmp(*argv, "inherit") != 0) {
 208                                 if (rtnl_dsfield_a2n(&uval, *argv))
 209                                         invarg("bad TOS value", *argv);
 210                                 p->iph.tos = uval;
 211                         } else
 212                                 p->iph.tos = 1;
 213                 } else {
 214                         if (strcmp(*argv, "name") == 0) {
 215                                 NEXT_ARG();
 216                         } else if (matches(*argv, "help") == 0)
 217                                 usage();
 218                         if (p->name[0])
 219                                 duparg2("name", *argv);
 220                         strncpy(p->name, *argv, IFNAMSIZ);
 221                         if (cmd == SIOCCHGTUNNEL && count == 0) {
 222                                 struct ip_tunnel_parm old_p;
 223                                 memset(&old_p, 0, sizeof(old_p));
 224                                 if (tnl_get_ioctl(*argv, &old_p))
 225                                         return -1;
 226                                 *p = old_p;
 227                         }
 228                 }
 229                 count++;
 230                 argc--; argv++;
 231         }
 232
 233
 234         if (p->iph.protocol == 0) {
 235                 if (memcmp(p->name, "gre", 3) == 0)
 236                         p->iph.protocol = IPPROTO_GRE;
 237                 else if (memcmp(p->name, "ipip", 4) == 0)
 238                         p->iph.protocol = IPPROTO_IPIP;
 239                 else if (memcmp(p->name, "sit", 3) == 0)
 240                         p->iph.protocol = IPPROTO_IPV6;
 241                 else if (memcmp(p->name, "isatap", 6) == 0) {
 242                         p->iph.protocol = IPPROTO_IPV6;
 243                         isatap++;
 244                 }
 245         }
 246
 247         if (p->iph.protocol == IPPROTO_IPIP || p->iph.protocol == IPPROTO_IPV6) {
 248                 if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) {
 249                         fprintf(stderr, "Keys are not allowed with ipip and sit.\n");
 250                         return -1;
 251                 }
 252         }
 253
 254         if (medium[0]) {
 255                 p->link = tnl_ioctl_get_ifindex(medium);
 256                 if (p->link == 0)
 257                         return -1;
 258         }
 259
 260         if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
 261                 p->i_key = p->iph.daddr;
 262                 p->i_flags |= GRE_KEY;
 263         }
 264         if (p->o_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
 265                 p->o_key = p->iph.daddr;
 266                 p->o_flags |= GRE_KEY;
 267         }
 268         if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) {
 269                 fprintf(stderr, "Broadcast tunnel requires a source address.\n");
 270                 return -1;
 271         }
 272         if (isatap) {
 273                 if (p->iph.daddr) {
 274                         fprintf(stderr, "no remote with isatap.\n");
 275                         return -1;
 276                 }
 277                 p->i_flags |= SIT_ISATAP;
 278         }
 279
 280         return 0;
 281 }
 282
 283
 284 static int do_add(int cmd, int argc, char **argv)
 285 {
 286         struct ip_tunnel_parm p;
 287
 288         if (parse_args(argc, argv, cmd, &p) < 0)
 289                 return -1;
 290
 291         if (p.iph.ttl && p.iph.frag_off == 0) {
 292                 fprintf(stderr, "ttl != 0 and noptmudisc are incompatible\n");
 293                 return -1;
 294         }
 295
 296         switch (p.iph.protocol) {
 297         case IPPROTO_IPIP:
 298                 return tnl_add_ioctl(cmd, "tunl0", p.name, &p);
 299         case IPPROTO_GRE:
 300                 return tnl_add_ioctl(cmd, "gre0", p.name, &p);
 301         case IPPROTO_IPV6:
 302                 return tnl_add_ioctl(cmd, "sit0", p.name, &p);
 303         default:
 304                 fprintf(stderr, "cannot determine tunnel mode (ipip, gre or sit)\n");
 305                 return -1;
 306         }
 307         return -1;
 308 }
 309
 310 static int do_del(int argc, char **argv)
 311 {
 312         struct ip_tunnel_parm p;
 313
 314         if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0)
 315                 return -1;
 316
 317         switch (p.iph.protocol) {
 318         case IPPROTO_IPIP:
 319                 return tnl_del_ioctl("tunl0", p.name, &p);
 320         case IPPROTO_GRE:
 321                 return tnl_del_ioctl("gre0", p.name, &p);
 322         case IPPROTO_IPV6:
 323                 return tnl_del_ioctl("sit0", p.name, &p);
 324         default:
 325                 return tnl_del_ioctl(p.name, p.name, &p);
 326         }
 327         return -1;
 328 }
 329
 330 static void print_tunnel(struct ip_tunnel_parm *p)
 331 {
 332         char s1[1024];
 333         char s2[1024];
 334         char s3[64];
 335         char s4[64];
 336
 337         inet_ntop(AF_INET, &p->i_key, s3, sizeof(s3));
 338         inet_ntop(AF_INET, &p->o_key, s4, sizeof(s4));
 339
 340         /* Do not use format_host() for local addr,
 341          * symbolic name will not be useful.
 342          */
 343      if(p->proto_type == ETH_P_ETH)
 344                   printf("%s: %s/eth  remote %s  local %s ",
 345                           p->name,
 346                           tnl_strproto(p->iph.protocol),
 347                           p->iph.daddr ? format_host(AF_INET, 4, &p->iph.daddr, s1, sizeof(s1))  : "any",
 348                           p->iph.saddr ? rt_addr_n2a(AF_INET, 4, &p->iph.saddr, s2, sizeof(s2)) : "any");
 349      else
 350         printf("%s: %s/ip  remote %s  local %s ",
 351                p->name,
 352                tnl_strproto(p->iph.protocol),
 353                p->iph.daddr ? format_host(AF_INET, 4, &p->iph.daddr, s1, sizeof(s1))  : "any",
 354                p->iph.saddr ? rt_addr_n2a(AF_INET, 4, &p->iph.saddr, s2, sizeof(s2)) : "any");
 355
 356         if (p->link) {
 357                 char *n = tnl_ioctl_get_ifname(p->link);
 358                 if (n)
 359                         printf(" dev %s ", n);
 360         }
 361
 362         if (p->iph.ttl)
 363                 printf(" ttl %d ", p->iph.ttl);
 364         else
 365                 printf(" ttl inherit ");
 366
 367         if (p->iph.tos) {
 368                 SPRINT_BUF(b1);
 369                 printf(" tos");
 370                 if (p->iph.tos&1)
 371                         printf(" inherit");
 372                 if (p->iph.tos&~1)
 373                         printf("%c%s ", p->iph.tos&1 ? '/' : ' ',
 374                                rtnl_dsfield_n2a(p->iph.tos&~1, b1, sizeof(b1)));
 375         }
 376
 377         if (!(p->iph.frag_off&htons(IP_DF)))
 378                 printf(" nopmtudisc");
 379
 380         if ((p->i_flags&GRE_KEY) && (p->o_flags&GRE_KEY) && p->o_key == p->i_key)
 381                 printf(" key %s", s3);
 382         else if ((p->i_flags|p->o_flags)&GRE_KEY) {
 383                 if (p->i_flags&GRE_KEY)
 384                         printf(" ikey %s ", s3);
 385                 if (p->o_flags&GRE_KEY)
 386                         printf(" okey %s ", s4);
 387         }
 388
 389         if (p->i_flags&GRE_SEQ)
 390                 printf("%s  Drop packets out of sequence.\n", _SL_);
 391         if (p->i_flags&GRE_CSUM)
 392                 printf("%s  Checksum in received packet is required.", _SL_);
 393         if (p->o_flags&GRE_SEQ)
 394                 printf("%s  Sequence packets on output.", _SL_);
 395         if (p->o_flags&GRE_CSUM)
 396                 printf("%s  Checksum output packets.", _SL_);
 397 }
 398
 399 static int do_tunnels_list(struct ip_tunnel_parm *p)
 400 {
 401         char name[IFNAMSIZ];
 402         unsigned long  rx_bytes, rx_packets, rx_errs, rx_drops,
 403         rx_fifo, rx_frame,
 404         tx_bytes, tx_packets, tx_errs, tx_drops,
 405         tx_fifo, tx_colls, tx_carrier, rx_multi;
 406         int type;
 407         struct ip_tunnel_parm p1;
 408
 409         char buf[512];
 410         FILE *fp = fopen("/proc/net/dev", "r");
 411         if (fp == NULL) {
 412                 perror("fopen");
 413                 return -1;
 414         }
 415
 416         fgets(buf, sizeof(buf), fp);
 417         fgets(buf, sizeof(buf), fp);
 418
 419         while (fgets(buf, sizeof(buf), fp) != NULL) {
 420                 char *ptr;
 421                 buf[sizeof(buf) - 1] = 0;
 422                 if ((ptr = strchr(buf, ':')) == NULL ||
 423                     (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) {
 424                         fprintf(stderr, "Wrong format of /proc/net/dev. Sorry.\n");
 425                         return -1;
 426                 }
 427                 if (sscanf(ptr, "%ld%ld%ld%ld%ld%ld%ld%*d%ld%ld%ld%ld%ld%ld%ld",
 428                            &rx_bytes, &rx_packets, &rx_errs, &rx_drops,
 429                            &rx_fifo, &rx_frame, &rx_multi,
 430                            &tx_bytes, &tx_packets, &tx_errs, &tx_drops,
 431                            &tx_fifo, &tx_colls, &tx_carrier) != 14)
 432                         continue;
 433                 if (p->name[0] && strcmp(p->name, name))
 434                         continue;
 435                 type = tnl_ioctl_get_iftype(name);
 436                 if (type == -1) {
 437                         fprintf(stderr, "Failed to get type of [%s]\n", name);
 438                         continue;
 439                 }
 440                 if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT)
 441                         continue;
 442                 memset(&p1, 0, sizeof(p1));
 443                 if (tnl_get_ioctl(name, &p1))
 444                         continue;
 445                 if ((p->link && p1.link != p->link) ||
 446                     (p->name[0] && strcmp(p1.name, p->name)) ||
 447                     (p->iph.daddr && p1.iph.daddr != p->iph.daddr) ||
 448                     (p->iph.saddr && p1.iph.saddr != p->iph.saddr) ||
 449                     (p->i_key && p1.i_key != p->i_key))
 450                         continue;
 451                 print_tunnel(&p1);
 452                 if (show_stats) {
 453                         printf("%s", _SL_);
 454                         printf("RX: Packets    Bytes        Errors CsumErrs OutOfSeq Mcasts%s", _SL_);
 455                         printf("    %-10ld %-12ld %-6ld %-8ld %-8ld %-8ld%s",
 456                                rx_packets, rx_bytes, rx_errs, rx_frame, rx_fifo, rx_multi, _SL_);
 457                         printf("TX: Packets    Bytes        Errors DeadLoop NoRoute  NoBufs%s", _SL_);
 458                         printf("    %-10ld %-12ld %-6ld %-8ld %-8ld %-6ld",
 459                                tx_packets, tx_bytes, tx_errs, tx_colls, tx_carrier, tx_drops);
 460                 }
 461                 printf("\n");
 462         }
 463         return 0;
 464 }
 465
 466 static int do_show(int argc, char **argv)
 467 {
 468         int err;
 469         struct ip_tunnel_parm p;
 470
 471         if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0)
 472                 return -1;
 473
 474         switch (p.iph.protocol) {
 475         case IPPROTO_IPIP:
 476                 err = tnl_get_ioctl(p.name[0] ? p.name : "tunl0", &p);
 477                 break;
 478         case IPPROTO_GRE:
 479                 err = tnl_get_ioctl(p.name[0] ? p.name : "gre0", &p);
 480                 break;
 481         case IPPROTO_IPV6:
 482                 err = tnl_get_ioctl(p.name[0] ? p.name : "sit0", &p);
 483                 break;
 484         default:
 485                 do_tunnels_list(&p);
 486                 return 0;
 487         }
 488         if (err)
 489                 return -1;
 490
 491         print_tunnel(&p);
 492         printf("\n");
 493         return 0;
 494 }
 495
 496 int do_iptunnel(int argc, char **argv)
 497 {
 498         switch (preferred_family) {
 499         case AF_UNSPEC:
 500                 preferred_family = AF_INET;
 501                 break;
 502         case AF_INET:
 503                 break;
 504         /*
 505          * This is silly enough but we have no easy way to make it
 506          * protocol-independent because of unarranged structure between
 507          * IPv4 and IPv6.
 508          */
 509         case AF_INET6:
 510                 return do_ip6tunnel(argc, argv);
 511         default:
 512                 fprintf(stderr, "Unsupported family:%d\n", preferred_family);
 513                 exit(-1);
 514         }
 515
 516         if (argc > 0) {
 517                 if (matches(*argv, "add") == 0)
 518                         return do_add(SIOCADDTUNNEL, argc-1, argv+1);
 519                 if (matches(*argv, "change") == 0)
 520                         return do_add(SIOCCHGTUNNEL, argc-1, argv+1);
 521                 if (matches(*argv, "del") == 0)
 522                         return do_del(argc-1, argv+1);
 523                 if (matches(*argv, "show") == 0 ||
 524                     matches(*argv, "lst") == 0 ||
 525                     matches(*argv, "list") == 0)
 526                         return do_show(argc-1, argv+1);
 527                 if (matches(*argv, "help") == 0)
 528                         usage();
 529         } else
 530                 return do_show(0, NULL);
 531
 532         fprintf(stderr, "Command \"%s\" is unknown, try \"ip tunnel help\".\n", *argv);
 533         exit(-1);
 534 }