ip/ip6tunnel.c

   1 /*
   2  * Copyright (C)2006 USAGI/WIDE Project
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses>.
  16  */
  17 /*
  18  * Author:
  19  *      Masahide NAKAMURA @USAGI
  20  */
  21
  22 #include <stdio.h>
  23 #include <string.h>
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <sys/types.h>
  27 #include <sys/socket.h>
  28 #include <arpa/inet.h>
  29 #include <sys/ioctl.h>
  30 #include <linux/ip.h>
  31 #include <linux/if.h>
  32 #include <linux/if_arp.h>
  33 #include <linux/if_tunnel.h>
  34 #include <linux/ip6_tunnel.h>
  35
  36 #include "utils.h"
  37 #include "tunnel.h"
  38 #include "ip_common.h"
  39
  40 #define IP6_FLOWINFO_TCLASS     htonl(0x0FF00000)
  41 #define IP6_FLOWINFO_FLOWLABEL  htonl(0x000FFFFF)
  42
  43 #define DEFAULT_TNL_HOP_LIMIT   (64)
  44
  45 static void usage(void) __attribute__((noreturn));
  46
  47 static void usage(void)
  48 {
  49         fprintf(stderr, "Usage: ip -f inet6 tunnel { add | change | del | show } [ NAME ]\n");
  50         fprintf(stderr, "          [ mode { ip6ip6 | ipip6 | ip6gre | vti6 | any } ]\n");
  51         fprintf(stderr, "          [ remote ADDR local ADDR ] [ dev PHYS_DEV ]\n");
  52         fprintf(stderr, "          [ encaplimit ELIM ]\n");
  53         fprintf(stderr, "          [ hoplimit TTL ] [ tclass TCLASS ] [ flowlabel FLOWLABEL ]\n");
  54         fprintf(stderr, "          [ dscp inherit ]\n");
  55         fprintf(stderr, "          [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n");
  56         fprintf(stderr, "\n");
  57         fprintf(stderr, "Where: NAME      := STRING\n");
  58         fprintf(stderr, "       ADDR      := IPV6_ADDRESS\n");
  59         fprintf(stderr, "       ELIM      := { none | 0..255 }(default=%d)\n",
  60                 IPV6_DEFAULT_TNL_ENCAP_LIMIT);
  61         fprintf(stderr, "       TTL       := 0..255 (default=%d)\n",
  62                 DEFAULT_TNL_HOP_LIMIT);
  63         fprintf(stderr, "       TCLASS    := { 0x0..0xff | inherit }\n");
  64         fprintf(stderr, "       FLOWLABEL := { 0x0..0xfffff | inherit }\n");
  65         fprintf(stderr, "       KEY       := { DOTTED_QUAD | NUMBER }\n");
  66         exit(-1);
  67 }
  68
  69 static void print_tunnel(struct ip6_tnl_parm2 *p)
  70 {
  71         char s1[1024];
  72         char s2[1024];
  73
  74         /* Do not use format_host() for local addr,
  75          * symbolic name will not be useful.
  76          */
  77         printf("%s: %s/ipv6 remote %s local %s",
  78                p->name,
  79                tnl_strproto(p->proto),
  80                format_host(AF_INET6, 16, &p->raddr, s1, sizeof(s1)),
  81                rt_addr_n2a(AF_INET6, 16, &p->laddr, s2, sizeof(s2)));
  82         if (p->link) {
  83                 const char *n = ll_index_to_name(p->link);
  84
  85                 if (n)
  86                         printf(" dev %s", n);
  87         }
  88
  89         if (p->flags & IP6_TNL_F_IGN_ENCAP_LIMIT)
  90                 printf(" encaplimit none");
  91         else
  92                 printf(" encaplimit %u", p->encap_limit);
  93
  94         printf(" hoplimit %u", p->hop_limit);
  95
  96         if (p->flags & IP6_TNL_F_USE_ORIG_TCLASS)
  97                 printf(" tclass inherit");
  98         else {
  99                 __u32 val = ntohl(p->flowinfo & IP6_FLOWINFO_TCLASS);
 100
 101                 printf(" tclass 0x%02x", (__u8)(val >> 20));
 102         }
 103
 104         if (p->flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 105                 printf(" flowlabel inherit");
 106         else
 107                 printf(" flowlabel 0x%05x", ntohl(p->flowinfo & IP6_FLOWINFO_FLOWLABEL));
 108
 109         printf(" (flowinfo 0x%08x)", ntohl(p->flowinfo));
 110
 111         if (p->flags & IP6_TNL_F_RCV_DSCP_COPY)
 112                 printf(" dscp inherit");
 113
 114         if (p->proto == IPPROTO_GRE) {
 115                 if ((p->i_flags & GRE_KEY) && (p->o_flags & GRE_KEY) && p->o_key == p->i_key)
 116                         printf(" key %u", ntohl(p->i_key));
 117                 else if ((p->i_flags | p->o_flags) & GRE_KEY) {
 118                         if (p->i_flags & GRE_KEY)
 119                                 printf(" ikey %u", ntohl(p->i_key));
 120                         if (p->o_flags & GRE_KEY)
 121                                 printf(" okey %u", ntohl(p->o_key));
 122                 }
 123
 124                 if (p->i_flags & GRE_SEQ)
 125                         printf("%s  Drop packets out of sequence.", _SL_);
 126                 if (p->i_flags & GRE_CSUM)
 127                         printf("%s  Checksum in received packet is required.", _SL_);
 128                 if (p->o_flags & GRE_SEQ)
 129                         printf("%s  Sequence packets on output.", _SL_);
 130                 if (p->o_flags & GRE_CSUM)
 131                         printf("%s  Checksum output packets.", _SL_);
 132         }
 133 }
 134
 135 static int parse_args(int argc, char **argv, int cmd, struct ip6_tnl_parm2 *p)
 136 {
 137         int count = 0;
 138         char medium[IFNAMSIZ];
 139
 140         memset(medium, 0, sizeof(medium));
 141
 142         while (argc > 0) {
 143                 if (strcmp(*argv, "mode") == 0) {
 144                         NEXT_ARG();
 145                         if (strcmp(*argv, "ipv6/ipv6") == 0 ||
 146                             strcmp(*argv, "ip6ip6") == 0)
 147                                 p->proto = IPPROTO_IPV6;
 148                         else if (strcmp(*argv, "vti6") == 0) {
 149                                 p->proto = IPPROTO_IPV6;
 150                                 p->i_flags |= VTI_ISVTI;
 151                         } else if (strcmp(*argv, "ip/ipv6") == 0 ||
 152                                  strcmp(*argv, "ipv4/ipv6") == 0 ||
 153                                  strcmp(*argv, "ipip6") == 0 ||
 154                                  strcmp(*argv, "ip4ip6") == 0)
 155                                 p->proto = IPPROTO_IPIP;
 156                         else if (strcmp(*argv, "ip6gre") == 0 ||
 157                                  strcmp(*argv, "gre/ipv6") == 0)
 158                                 p->proto = IPPROTO_GRE;
 159                         else if (strcmp(*argv, "any/ipv6") == 0 ||
 160                                  strcmp(*argv, "any") == 0)
 161                                 p->proto = 0;
 162                         else {
 163                                 fprintf(stderr, "Unknown tunnel mode \"%s\"\n", *argv);
 164                                 exit(-1);
 165                         }
 166                 } else if (strcmp(*argv, "remote") == 0) {
 167                         inet_prefix raddr;
 168
 169                         NEXT_ARG();
 170                         get_prefix(&raddr, *argv, preferred_family);
 171                         if (raddr.family == AF_UNSPEC)
 172                                 invarg("\"remote\" address family is AF_UNSPEC", *argv);
 173                         memcpy(&p->raddr, &raddr.data, sizeof(p->raddr));
 174                 } else if (strcmp(*argv, "local") == 0) {
 175                         inet_prefix laddr;
 176
 177                         NEXT_ARG();
 178                         get_prefix(&laddr, *argv, preferred_family);
 179                         if (laddr.family == AF_UNSPEC)
 180                                 invarg("\"local\" address family is AF_UNSPEC", *argv);
 181                         memcpy(&p->laddr, &laddr.data, sizeof(p->laddr));
 182                 } else if (strcmp(*argv, "dev") == 0) {
 183                         NEXT_ARG();
 184                         strncpy(medium, *argv, IFNAMSIZ - 1);
 185                 } else if (strcmp(*argv, "encaplimit") == 0) {
 186                         NEXT_ARG();
 187                         if (strcmp(*argv, "none") == 0) {
 188                                 p->flags |= IP6_TNL_F_IGN_ENCAP_LIMIT;
 189                         } else {
 190                                 __u8 uval;
 191
 192                                 if (get_u8(&uval, *argv, 0) < -1)
 193                                         invarg("invalid ELIM", *argv);
 194                                 p->encap_limit = uval;
 195                                 p->flags &= ~IP6_TNL_F_IGN_ENCAP_LIMIT;
 196                         }
 197                 } else if (strcmp(*argv, "hoplimit") == 0 ||
 198                            strcmp(*argv, "ttl") == 0 ||
 199                            strcmp(*argv, "hlim") == 0) {
 200                         __u8 uval;
 201
 202                         NEXT_ARG();
 203                         if (get_u8(&uval, *argv, 0))
 204                                 invarg("invalid TTL", *argv);
 205                         p->hop_limit = uval;
 206                 } else if (strcmp(*argv, "tclass") == 0 ||
 207                            strcmp(*argv, "tc") == 0 ||
 208                            strcmp(*argv, "tos") == 0 ||
 209                            matches(*argv, "dsfield") == 0) {
 210                         __u8 uval;
 211
 212                         NEXT_ARG();
 213                         p->flowinfo &= ~IP6_FLOWINFO_TCLASS;
 214                         if (strcmp(*argv, "inherit") == 0)
 215                                 p->flags |= IP6_TNL_F_USE_ORIG_TCLASS;
 216                         else {
 217                                 if (get_u8(&uval, *argv, 16))
 218                                         invarg("invalid TClass", *argv);
 219                                 p->flowinfo |= htonl((__u32)uval << 20) & IP6_FLOWINFO_TCLASS;
 220                                 p->flags &= ~IP6_TNL_F_USE_ORIG_TCLASS;
 221                         }
 222                 } else if (strcmp(*argv, "flowlabel") == 0 ||
 223                            strcmp(*argv, "fl") == 0) {
 224                         __u32 uval;
 225
 226                         NEXT_ARG();
 227                         p->flowinfo &= ~IP6_FLOWINFO_FLOWLABEL;
 228                         if (strcmp(*argv, "inherit") == 0)
 229                                 p->flags |= IP6_TNL_F_USE_ORIG_FLOWLABEL;
 230                         else {
 231                                 if (get_u32(&uval, *argv, 16))
 232                                         invarg("invalid Flowlabel", *argv);
 233                                 if (uval > 0xFFFFF)
 234                                         invarg("invalid Flowlabel", *argv);
 235                                 p->flowinfo |= htonl(uval) & IP6_FLOWINFO_FLOWLABEL;
 236                                 p->flags &= ~IP6_TNL_F_USE_ORIG_FLOWLABEL;
 237                         }
 238                 } else if (strcmp(*argv, "dscp") == 0) {
 239                         NEXT_ARG();
 240                         if (strcmp(*argv, "inherit") != 0)
 241                                 invarg("not inherit", *argv);
 242                         p->flags |= IP6_TNL_F_RCV_DSCP_COPY;
 243                 } else if (strcmp(*argv, "key") == 0) {
 244                         NEXT_ARG();
 245                         p->i_flags |= GRE_KEY;
 246                         p->o_flags |= GRE_KEY;
 247                         p->i_key = p->o_key = tnl_parse_key("key", *argv);
 248                 } else if (strcmp(*argv, "ikey") == 0) {
 249                         NEXT_ARG();
 250                         p->i_flags |= GRE_KEY;
 251                         p->i_key = tnl_parse_key("ikey", *argv);
 252                 } else if (strcmp(*argv, "okey") == 0) {
 253                         NEXT_ARG();
 254                         p->o_flags |= GRE_KEY;
 255                         p->o_key = tnl_parse_key("okey", *argv);
 256                 } else if (strcmp(*argv, "seq") == 0) {
 257                         p->i_flags |= GRE_SEQ;
 258                         p->o_flags |= GRE_SEQ;
 259                 } else if (strcmp(*argv, "iseq") == 0) {
 260                         p->i_flags |= GRE_SEQ;
 261                 } else if (strcmp(*argv, "oseq") == 0) {
 262                         p->o_flags |= GRE_SEQ;
 263                 } else if (strcmp(*argv, "csum") == 0) {
 264                         p->i_flags |= GRE_CSUM;
 265                         p->o_flags |= GRE_CSUM;
 266                 } else if (strcmp(*argv, "icsum") == 0) {
 267                         p->i_flags |= GRE_CSUM;
 268                 } else if (strcmp(*argv, "ocsum") == 0) {
 269                         p->o_flags |= GRE_CSUM;
 270                 } else {
 271                         if (strcmp(*argv, "name") == 0) {
 272                                 NEXT_ARG();
 273                         } else if (matches(*argv, "help") == 0)
 274                                 usage();
 275                         if (p->name[0])
 276                                 duparg2("name", *argv);
 277                         strncpy(p->name, *argv, IFNAMSIZ - 1);
 278                         if (cmd == SIOCCHGTUNNEL && count == 0) {
 279                                 struct ip6_tnl_parm2 old_p;
 280
 281                                 memset(&old_p, 0, sizeof(old_p));
 282                                 if (tnl_get_ioctl(*argv, &old_p))
 283                                         return -1;
 284                                 *p = old_p;
 285                         }
 286                 }
 287                 count++;
 288                 argc--; argv++;
 289         }
 290         if (medium[0]) {
 291                 p->link = ll_name_to_index(medium);
 292                 if (p->link == 0) {
 293                         fprintf(stderr, "Cannot find device \"%s\"\n", medium);
 294                         return -1;
 295                 }
 296         }
 297         return 0;
 298 }
 299
 300 static void ip6_tnl_parm_init(struct ip6_tnl_parm2 *p, int apply_default)
 301 {
 302         memset(p, 0, sizeof(*p));
 303         p->proto = IPPROTO_IPV6;
 304         if (apply_default) {
 305                 p->hop_limit = DEFAULT_TNL_HOP_LIMIT;
 306                 p->encap_limit = IPV6_DEFAULT_TNL_ENCAP_LIMIT;
 307         }
 308 }
 309
 310 /*
 311  * @p1: user specified parameter
 312  * @p2: database entry
 313  */
 314 static int ip6_tnl_parm_match(const struct ip6_tnl_parm2 *p1,
 315                               const struct ip6_tnl_parm2 *p2)
 316 {
 317         return ((!p1->link || p1->link == p2->link) &&
 318                 (!p1->name[0] || strcmp(p1->name, p2->name) == 0) &&
 319                 (memcmp(&p1->laddr, &in6addr_any, sizeof(p1->laddr)) == 0 ||
 320                  memcmp(&p1->laddr, &p2->laddr, sizeof(p1->laddr)) == 0) &&
 321                 (memcmp(&p1->raddr, &in6addr_any, sizeof(p1->raddr)) == 0 ||
 322                  memcmp(&p1->raddr, &p2->raddr, sizeof(p1->raddr)) == 0) &&
 323                 (!p1->proto || !p2->proto || p1->proto == p2->proto) &&
 324                 (!p1->encap_limit || p1->encap_limit == p2->encap_limit) &&
 325                 (!p1->hop_limit || p1->hop_limit == p2->hop_limit) &&
 326                 (!(p1->flowinfo & IP6_FLOWINFO_TCLASS) ||
 327                  !((p1->flowinfo ^ p2->flowinfo) & IP6_FLOWINFO_TCLASS)) &&
 328                 (!(p1->flowinfo & IP6_FLOWINFO_FLOWLABEL) ||
 329                  !((p1->flowinfo ^ p2->flowinfo) & IP6_FLOWINFO_FLOWLABEL)) &&
 330                 (!p1->flags || (p1->flags & p2->flags)));
 331 }
 332
 333 static int do_tunnels_list(struct ip6_tnl_parm2 *p)
 334 {
 335         char buf[512];
 336         int err = -1;
 337         FILE *fp = fopen("/proc/net/dev", "r");
 338
 339         if (fp == NULL) {
 340                 perror("fopen");
 341                 return -1;
 342         }
 343
 344         /* skip two lines at the begenning of the file */
 345         if (!fgets(buf, sizeof(buf), fp) ||
 346             !fgets(buf, sizeof(buf), fp)) {
 347                 fprintf(stderr, "/proc/net/dev read error\n");
 348                 goto end;
 349         }
 350
 351         while (fgets(buf, sizeof(buf), fp) != NULL) {
 352                 char name[IFNAMSIZ];
 353                 int index, type;
 354                 struct ip6_tnl_parm2 p1;
 355                 char *ptr;
 356
 357                 buf[sizeof(buf) - 1] = '\0';
 358                 if ((ptr = strchr(buf, ':')) == NULL ||
 359                     (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) {
 360                         fprintf(stderr, "Wrong format for /proc/net/dev. Giving up.\n");
 361                         goto end;
 362                 }
 363                 if (p->name[0] && strcmp(p->name, name))
 364                         continue;
 365                 index = ll_name_to_index(name);
 366                 if (index == 0)
 367                         continue;
 368                 type = ll_index_to_type(index);
 369                 if (type == -1) {
 370                         fprintf(stderr, "Failed to get type of \"%s\"\n", name);
 371                         continue;
 372                 }
 373                 if (type != ARPHRD_TUNNEL6 && type != ARPHRD_IP6GRE)
 374                         continue;
 375                 memset(&p1, 0, sizeof(p1));
 376                 ip6_tnl_parm_init(&p1, 0);
 377                 if (type == ARPHRD_IP6GRE)
 378                         p1.proto = IPPROTO_GRE;
 379                 strcpy(p1.name, name);
 380                 p1.link = ll_name_to_index(p1.name);
 381                 if (p1.link == 0)
 382                         continue;
 383                 if (tnl_get_ioctl(p1.name, &p1))
 384                         continue;
 385                 if (!ip6_tnl_parm_match(p, &p1))
 386                         continue;
 387                 print_tunnel(&p1);
 388                 if (show_stats)
 389                         tnl_print_stats(ptr);
 390                 printf("\n");
 391         }
 392         err = 0;
 393  end:
 394         fclose(fp);
 395         return err;
 396 }
 397
 398 static int do_show(int argc, char **argv)
 399 {
 400         struct ip6_tnl_parm2 p;
 401
 402         ll_init_map(&rth);
 403         ip6_tnl_parm_init(&p, 0);
 404         p.proto = 0;  /* default to any */
 405
 406         if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0)
 407                 return -1;
 408
 409         if (!p.name[0] || show_stats)
 410                 do_tunnels_list(&p);
 411         else {
 412                 if (tnl_get_ioctl(p.name, &p))
 413                         return -1;
 414                 print_tunnel(&p);
 415                 printf("\n");
 416         }
 417
 418         return 0;
 419 }
 420
 421 static int do_add(int cmd, int argc, char **argv)
 422 {
 423         struct ip6_tnl_parm2 p;
 424         const char *basedev = "ip6tnl0";
 425
 426         ip6_tnl_parm_init(&p, 1);
 427
 428         if (parse_args(argc, argv, cmd, &p) < 0)
 429                 return -1;
 430
 431         if (p.proto == IPPROTO_GRE)
 432                 basedev = "ip6gre0";
 433         else if (p.i_flags & VTI_ISVTI)
 434                 basedev = "ip6_vti0";
 435
 436         return tnl_add_ioctl(cmd, basedev, p.name, &p);
 437 }
 438
 439 static int do_del(int argc, char **argv)
 440 {
 441         struct ip6_tnl_parm2 p;
 442         const char *basedev = "ip6tnl0";
 443
 444         ip6_tnl_parm_init(&p, 1);
 445
 446         if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0)
 447                 return -1;
 448
 449         if (p.proto == IPPROTO_GRE)
 450                 basedev = "ip6gre0";
 451         else if (p.i_flags & VTI_ISVTI)
 452                 basedev = "ip6_vti0";
 453
 454         return tnl_del_ioctl(basedev, p.name, &p);
 455 }
 456
 457 int do_ip6tunnel(int argc, char **argv)
 458 {
 459         switch (preferred_family) {
 460         case AF_UNSPEC:
 461                 preferred_family = AF_INET6;
 462                 break;
 463         case AF_INET6:
 464                 break;
 465         default:
 466                 fprintf(stderr, "Unsupported protocol family: %d\n", preferred_family);
 467                 exit(-1);
 468         }
 469
 470         if (argc > 0) {
 471                 if (matches(*argv, "add") == 0)
 472                         return do_add(SIOCADDTUNNEL, argc - 1, argv + 1);
 473                 if (matches(*argv, "change") == 0)
 474                         return do_add(SIOCCHGTUNNEL, argc - 1, argv + 1);
 475                 if (matches(*argv, "delete") == 0)
 476                         return do_del(argc - 1, argv + 1);
 477                 if (matches(*argv, "show") == 0 ||
 478                     matches(*argv, "lst") == 0 ||
 479                     matches(*argv, "list") == 0)
 480                         return do_show(argc - 1, argv + 1);
 481                 if (matches(*argv, "help") == 0)
 482                         usage();
 483         } else
 484                 return do_show(0, NULL);
 485
 486         fprintf(stderr, "Command \"%s\" is unknown, try \"ip -f inet6 tunnel help\".\n", *argv);
 487         exit(-1);
 488 }