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_r(AF_INET6, 16, &p->raddr, s1, sizeof(s1)),
  81                rt_addr_n2a_r(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         while (argc > 0) {
 141                 if (strcmp(*argv, "mode") == 0) {
 142                         NEXT_ARG();
 143                         if (strcmp(*argv, "ipv6/ipv6") == 0 ||
 144                             strcmp(*argv, "ip6ip6") == 0)
 145                                 p->proto = IPPROTO_IPV6;
 146                         else if (strcmp(*argv, "vti6") == 0) {
 147                                 p->proto = IPPROTO_IPV6;
 148                                 p->i_flags |= VTI_ISVTI;
 149                         } else if (strcmp(*argv, "ip/ipv6") == 0 ||
 150                                  strcmp(*argv, "ipv4/ipv6") == 0 ||
 151                                  strcmp(*argv, "ipip6") == 0 ||
 152                                  strcmp(*argv, "ip4ip6") == 0)
 153                                 p->proto = IPPROTO_IPIP;
 154                         else if (strcmp(*argv, "ip6gre") == 0 ||
 155                                  strcmp(*argv, "gre/ipv6") == 0)
 156                                 p->proto = IPPROTO_GRE;
 157                         else if (strcmp(*argv, "any/ipv6") == 0 ||
 158                                  strcmp(*argv, "any") == 0)
 159                                 p->proto = 0;
 160                         else {
 161                                 fprintf(stderr, "Unknown tunnel mode \"%s\"\n", *argv);
 162                                 exit(-1);
 163                         }
 164                 } else if (strcmp(*argv, "remote") == 0) {
 165                         inet_prefix raddr;
 166
 167                         NEXT_ARG();
 168                         get_prefix(&raddr, *argv, preferred_family);
 169                         if (raddr.family == AF_UNSPEC)
 170                                 invarg("\"remote\" address family is AF_UNSPEC", *argv);
 171                         memcpy(&p->raddr, &raddr.data, sizeof(p->raddr));
 172                 } else if (strcmp(*argv, "local") == 0) {
 173                         inet_prefix laddr;
 174
 175                         NEXT_ARG();
 176                         get_prefix(&laddr, *argv, preferred_family);
 177                         if (laddr.family == AF_UNSPEC)
 178                                 invarg("\"local\" address family is AF_UNSPEC", *argv);
 179                         memcpy(&p->laddr, &laddr.data, sizeof(p->laddr));
 180                 } else if (strcmp(*argv, "dev") == 0) {
 181                         NEXT_ARG();
 182                         strncpy(medium, *argv, IFNAMSIZ - 1);
 183                 } else if (strcmp(*argv, "encaplimit") == 0) {
 184                         NEXT_ARG();
 185                         if (strcmp(*argv, "none") == 0) {
 186                                 p->flags |= IP6_TNL_F_IGN_ENCAP_LIMIT;
 187                         } else {
 188                                 __u8 uval;
 189
 190                                 if (get_u8(&uval, *argv, 0) < -1)
 191                                         invarg("invalid ELIM", *argv);
 192                                 p->encap_limit = uval;
 193                                 p->flags &= ~IP6_TNL_F_IGN_ENCAP_LIMIT;
 194                         }
 195                 } else if (strcmp(*argv, "hoplimit") == 0 ||
 196                            strcmp(*argv, "ttl") == 0 ||
 197                            strcmp(*argv, "hlim") == 0) {
 198                         __u8 uval;
 199
 200                         NEXT_ARG();
 201                         if (get_u8(&uval, *argv, 0))
 202                                 invarg("invalid TTL", *argv);
 203                         p->hop_limit = uval;
 204                 } else if (strcmp(*argv, "tclass") == 0 ||
 205                            strcmp(*argv, "tc") == 0 ||
 206                            strcmp(*argv, "tos") == 0 ||
 207                            matches(*argv, "dsfield") == 0) {
 208                         __u8 uval;
 209
 210                         NEXT_ARG();
 211                         p->flowinfo &= ~IP6_FLOWINFO_TCLASS;
 212                         if (strcmp(*argv, "inherit") == 0)
 213                                 p->flags |= IP6_TNL_F_USE_ORIG_TCLASS;
 214                         else {
 215                                 if (get_u8(&uval, *argv, 16))
 216                                         invarg("invalid TClass", *argv);
 217                                 p->flowinfo |= htonl((__u32)uval << 20) & IP6_FLOWINFO_TCLASS;
 218                                 p->flags &= ~IP6_TNL_F_USE_ORIG_TCLASS;
 219                         }
 220                 } else if (strcmp(*argv, "flowlabel") == 0 ||
 221                            strcmp(*argv, "fl") == 0) {
 222                         __u32 uval;
 223
 224                         NEXT_ARG();
 225                         p->flowinfo &= ~IP6_FLOWINFO_FLOWLABEL;
 226                         if (strcmp(*argv, "inherit") == 0)
 227                                 p->flags |= IP6_TNL_F_USE_ORIG_FLOWLABEL;
 228                         else {
 229                                 if (get_u32(&uval, *argv, 16))
 230                                         invarg("invalid Flowlabel", *argv);
 231                                 if (uval > 0xFFFFF)
 232                                         invarg("invalid Flowlabel", *argv);
 233                                 p->flowinfo |= htonl(uval) & IP6_FLOWINFO_FLOWLABEL;
 234                                 p->flags &= ~IP6_TNL_F_USE_ORIG_FLOWLABEL;
 235                         }
 236                 } else if (strcmp(*argv, "dscp") == 0) {
 237                         NEXT_ARG();
 238                         if (strcmp(*argv, "inherit") != 0)
 239                                 invarg("not inherit", *argv);
 240                         p->flags |= IP6_TNL_F_RCV_DSCP_COPY;
 241                 } else if (strcmp(*argv, "key") == 0) {
 242                         NEXT_ARG();
 243                         p->i_flags |= GRE_KEY;
 244                         p->o_flags |= GRE_KEY;
 245                         p->i_key = p->o_key = tnl_parse_key("key", *argv);
 246                 } else if (strcmp(*argv, "ikey") == 0) {
 247                         NEXT_ARG();
 248                         p->i_flags |= GRE_KEY;
 249                         p->i_key = tnl_parse_key("ikey", *argv);
 250                 } else if (strcmp(*argv, "okey") == 0) {
 251                         NEXT_ARG();
 252                         p->o_flags |= GRE_KEY;
 253                         p->o_key = tnl_parse_key("okey", *argv);
 254                 } else if (strcmp(*argv, "seq") == 0) {
 255                         p->i_flags |= GRE_SEQ;
 256                         p->o_flags |= GRE_SEQ;
 257                 } else if (strcmp(*argv, "iseq") == 0) {
 258                         p->i_flags |= GRE_SEQ;
 259                 } else if (strcmp(*argv, "oseq") == 0) {
 260                         p->o_flags |= GRE_SEQ;
 261                 } else if (strcmp(*argv, "csum") == 0) {
 262                         p->i_flags |= GRE_CSUM;
 263                         p->o_flags |= GRE_CSUM;
 264                 } else if (strcmp(*argv, "icsum") == 0) {
 265                         p->i_flags |= GRE_CSUM;
 266                 } else if (strcmp(*argv, "ocsum") == 0) {
 267                         p->o_flags |= GRE_CSUM;
 268                 } else {
 269                         if (strcmp(*argv, "name") == 0) {
 270                                 NEXT_ARG();
 271                         } else if (matches(*argv, "help") == 0)
 272                                 usage();
 273                         if (p->name[0])
 274                                 duparg2("name", *argv);
 275                         strncpy(p->name, *argv, IFNAMSIZ - 1);
 276                         if (cmd == SIOCCHGTUNNEL && count == 0) {
 277                                 struct ip6_tnl_parm2 old_p = {};
 278
 279                                 if (tnl_get_ioctl(*argv, &old_p))
 280                                         return -1;
 281                                 *p = old_p;
 282                         }
 283                 }
 284                 count++;
 285                 argc--; argv++;
 286         }
 287         if (medium[0]) {
 288                 p->link = ll_name_to_index(medium);
 289                 if (p->link == 0) {
 290                         fprintf(stderr, "Cannot find device \"%s\"\n", medium);
 291                         return -1;
 292                 }
 293         }
 294         return 0;
 295 }
 296
 297 static void ip6_tnl_parm_init(struct ip6_tnl_parm2 *p, int apply_default)
 298 {
 299         memset(p, 0, sizeof(*p));
 300         p->proto = IPPROTO_IPV6;
 301         if (apply_default) {
 302                 p->hop_limit = DEFAULT_TNL_HOP_LIMIT;
 303                 p->encap_limit = IPV6_DEFAULT_TNL_ENCAP_LIMIT;
 304         }
 305 }
 306
 307 /*
 308  * @p1: user specified parameter
 309  * @p2: database entry
 310  */
 311 static int ip6_tnl_parm_match(const struct ip6_tnl_parm2 *p1,
 312                               const struct ip6_tnl_parm2 *p2)
 313 {
 314         return ((!p1->link || p1->link == p2->link) &&
 315                 (!p1->name[0] || strcmp(p1->name, p2->name) == 0) &&
 316                 (memcmp(&p1->laddr, &in6addr_any, sizeof(p1->laddr)) == 0 ||
 317                  memcmp(&p1->laddr, &p2->laddr, sizeof(p1->laddr)) == 0) &&
 318                 (memcmp(&p1->raddr, &in6addr_any, sizeof(p1->raddr)) == 0 ||
 319                  memcmp(&p1->raddr, &p2->raddr, sizeof(p1->raddr)) == 0) &&
 320                 (!p1->proto || !p2->proto || p1->proto == p2->proto) &&
 321                 (!p1->encap_limit || p1->encap_limit == p2->encap_limit) &&
 322                 (!p1->hop_limit || p1->hop_limit == p2->hop_limit) &&
 323                 (!(p1->flowinfo & IP6_FLOWINFO_TCLASS) ||
 324                  !((p1->flowinfo ^ p2->flowinfo) & IP6_FLOWINFO_TCLASS)) &&
 325                 (!(p1->flowinfo & IP6_FLOWINFO_FLOWLABEL) ||
 326                  !((p1->flowinfo ^ p2->flowinfo) & IP6_FLOWINFO_FLOWLABEL)) &&
 327                 (!p1->flags || (p1->flags & p2->flags)));
 328 }
 329
 330 static int do_tunnels_list(struct ip6_tnl_parm2 *p)
 331 {
 332         char buf[512];
 333         int err = -1;
 334         FILE *fp = fopen("/proc/net/dev", "r");
 335
 336         if (fp == NULL) {
 337                 perror("fopen");
 338                 return -1;
 339         }
 340
 341         /* skip two lines at the begenning of the file */
 342         if (!fgets(buf, sizeof(buf), fp) ||
 343             !fgets(buf, sizeof(buf), fp)) {
 344                 fprintf(stderr, "/proc/net/dev read error\n");
 345                 goto end;
 346         }
 347
 348         while (fgets(buf, sizeof(buf), fp) != NULL) {
 349                 char name[IFNAMSIZ];
 350                 int index, type;
 351                 struct ip6_tnl_parm2 p1 = {};
 352                 char *ptr;
 353
 354                 buf[sizeof(buf) - 1] = '\0';
 355                 if ((ptr = strchr(buf, ':')) == NULL ||
 356                     (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) {
 357                         fprintf(stderr, "Wrong format for /proc/net/dev. Giving up.\n");
 358                         goto end;
 359                 }
 360                 if (p->name[0] && strcmp(p->name, name))
 361                         continue;
 362                 index = ll_name_to_index(name);
 363                 if (index == 0)
 364                         continue;
 365                 type = ll_index_to_type(index);
 366                 if (type == -1) {
 367                         fprintf(stderr, "Failed to get type of \"%s\"\n", name);
 368                         continue;
 369                 }
 370                 if (type != ARPHRD_TUNNEL6 && type != ARPHRD_IP6GRE)
 371                         continue;
 372                 ip6_tnl_parm_init(&p1, 0);
 373                 if (type == ARPHRD_IP6GRE)
 374                         p1.proto = IPPROTO_GRE;
 375                 strcpy(p1.name, name);
 376                 p1.link = ll_name_to_index(p1.name);
 377                 if (p1.link == 0)
 378                         continue;
 379                 if (tnl_get_ioctl(p1.name, &p1))
 380                         continue;
 381                 if (!ip6_tnl_parm_match(p, &p1))
 382                         continue;
 383                 print_tunnel(&p1);
 384                 if (show_stats)
 385                         tnl_print_stats(ptr);
 386                 printf("\n");
 387         }
 388         err = 0;
 389  end:
 390         fclose(fp);
 391         return err;
 392 }
 393
 394 static int do_show(int argc, char **argv)
 395 {
 396         struct ip6_tnl_parm2 p;
 397
 398         ll_init_map(&rth);
 399         ip6_tnl_parm_init(&p, 0);
 400         p.proto = 0;  /* default to any */
 401
 402         if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0)
 403                 return -1;
 404
 405         if (!p.name[0] || show_stats)
 406                 do_tunnels_list(&p);
 407         else {
 408                 if (tnl_get_ioctl(p.name, &p))
 409                         return -1;
 410                 print_tunnel(&p);
 411                 printf("\n");
 412         }
 413
 414         return 0;
 415 }
 416
 417 static int do_add(int cmd, int argc, char **argv)
 418 {
 419         struct ip6_tnl_parm2 p;
 420         const char *basedev = "ip6tnl0";
 421
 422         ip6_tnl_parm_init(&p, 1);
 423
 424         if (parse_args(argc, argv, cmd, &p) < 0)
 425                 return -1;
 426
 427         if (p.proto == IPPROTO_GRE)
 428                 basedev = "ip6gre0";
 429         else if (p.i_flags & VTI_ISVTI)
 430                 basedev = "ip6_vti0";
 431
 432         return tnl_add_ioctl(cmd, basedev, p.name, &p);
 433 }
 434
 435 static int do_del(int argc, char **argv)
 436 {
 437         struct ip6_tnl_parm2 p;
 438         const char *basedev = "ip6tnl0";
 439
 440         ip6_tnl_parm_init(&p, 1);
 441
 442         if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0)
 443                 return -1;
 444
 445         if (p.proto == IPPROTO_GRE)
 446                 basedev = "ip6gre0";
 447         else if (p.i_flags & VTI_ISVTI)
 448                 basedev = "ip6_vti0";
 449
 450         return tnl_del_ioctl(basedev, p.name, &p);
 451 }
 452
 453 int do_ip6tunnel(int argc, char **argv)
 454 {
 455         switch (preferred_family) {
 456         case AF_UNSPEC:
 457                 preferred_family = AF_INET6;
 458                 break;
 459         case AF_INET6:
 460                 break;
 461         default:
 462                 fprintf(stderr, "Unsupported protocol family: %d\n", preferred_family);
 463                 exit(-1);
 464         }
 465
 466         if (argc > 0) {
 467                 if (matches(*argv, "add") == 0)
 468                         return do_add(SIOCADDTUNNEL, argc - 1, argv + 1);
 469                 if (matches(*argv, "change") == 0)
 470                         return do_add(SIOCCHGTUNNEL, argc - 1, argv + 1);
 471                 if (matches(*argv, "delete") == 0)
 472                         return do_del(argc - 1, argv + 1);
 473                 if (matches(*argv, "show") == 0 ||
 474                     matches(*argv, "lst") == 0 ||
 475                     matches(*argv, "list") == 0)
 476                         return do_show(argc - 1, argv + 1);
 477                 if (matches(*argv, "help") == 0)
 478                         usage();
 479         } else
 480                 return do_show(0, NULL);
 481
 482         fprintf(stderr, "Command \"%s\" is unknown, try \"ip -f inet6 tunnel help\".\n", *argv);
 483         exit(-1);
 484 }