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, "          [ [no]allow-localremote ]\n");
  56         fprintf(stderr, "          [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n");
  57         fprintf(stderr, "\n");
  58         fprintf(stderr, "Where: NAME      := STRING\n");
  59         fprintf(stderr, "       ADDR      := IPV6_ADDRESS\n");
  60         fprintf(stderr, "       ELIM      := { none | 0..255 }(default=%d)\n",
  61                 IPV6_DEFAULT_TNL_ENCAP_LIMIT);
  62         fprintf(stderr, "       TTL       := 0..255 (default=%d)\n",
  63                 DEFAULT_TNL_HOP_LIMIT);
  64         fprintf(stderr, "       TCLASS    := { 0x0..0xff | inherit }\n");
  65         fprintf(stderr, "       FLOWLABEL := { 0x0..0xfffff | inherit }\n");
  66         fprintf(stderr, "       KEY       := { DOTTED_QUAD | NUMBER }\n");
  67         exit(-1);
  68 }
  69
  70 static void print_tunnel(struct ip6_tnl_parm2 *p)
  71 {
  72         char s1[1024];
  73         char s2[1024];
  74
  75         /* Do not use format_host() for local addr,
  76          * symbolic name will not be useful.
  77          */
  78         printf("%s: %s/ipv6 remote %s local %s",
  79                p->name,
  80                tnl_strproto(p->proto),
  81                format_host_r(AF_INET6, 16, &p->raddr, s1, sizeof(s1)),
  82                rt_addr_n2a_r(AF_INET6, 16, &p->laddr, s2, sizeof(s2)));
  83         if (p->link) {
  84                 const char *n = ll_index_to_name(p->link);
  85
  86                 if (n)
  87                         printf(" dev %s", n);
  88         }
  89
  90         if (p->flags & IP6_TNL_F_IGN_ENCAP_LIMIT)
  91                 printf(" encaplimit none");
  92         else
  93                 printf(" encaplimit %u", p->encap_limit);
  94
  95         printf(" hoplimit %u", p->hop_limit);
  96
  97         if (p->flags & IP6_TNL_F_USE_ORIG_TCLASS)
  98                 printf(" tclass inherit");
  99         else {
 100                 __u32 val = ntohl(p->flowinfo & IP6_FLOWINFO_TCLASS);
 101
 102                 printf(" tclass 0x%02x", (__u8)(val >> 20));
 103         }
 104
 105         if (p->flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 106                 printf(" flowlabel inherit");
 107         else
 108                 printf(" flowlabel 0x%05x", ntohl(p->flowinfo & IP6_FLOWINFO_FLOWLABEL));
 109
 110         printf(" (flowinfo 0x%08x)", ntohl(p->flowinfo));
 111
 112         if (p->flags & IP6_TNL_F_RCV_DSCP_COPY)
 113                 printf(" dscp inherit");
 114
 115         if (p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE)
 116                 printf(" allow-localremote");
 117
 118         if ((p->i_flags & GRE_KEY) && (p->o_flags & GRE_KEY) &&
 119             p->o_key == p->i_key)
 120                 printf(" key %u", ntohl(p->i_key));
 121         else {
 122                 if (p->i_flags & GRE_KEY)
 123                         printf(" ikey %u", ntohl(p->i_key));
 124                 if (p->o_flags & GRE_KEY)
 125                         printf(" okey %u", ntohl(p->o_key));
 126         }
 127
 128         if (p->proto == IPPROTO_GRE) {
 129                 if (p->i_flags & GRE_SEQ)
 130                         printf("%s  Drop packets out of sequence.", _SL_);
 131                 if (p->i_flags & GRE_CSUM)
 132                         printf("%s  Checksum in received packet is required.", _SL_);
 133                 if (p->o_flags & GRE_SEQ)
 134                         printf("%s  Sequence packets on output.", _SL_);
 135                 if (p->o_flags & GRE_CSUM)
 136                         printf("%s  Checksum output packets.", _SL_);
 137         }
 138 }
 139
 140 static int parse_args(int argc, char **argv, int cmd, struct ip6_tnl_parm2 *p)
 141 {
 142         int count = 0;
 143         const char *medium = NULL;
 144
 145         while (argc > 0) {
 146                 if (strcmp(*argv, "mode") == 0) {
 147                         NEXT_ARG();
 148                         if (strcmp(*argv, "ipv6/ipv6") == 0 ||
 149                             strcmp(*argv, "ip6ip6") == 0)
 150                                 p->proto = IPPROTO_IPV6;
 151                         else if (strcmp(*argv, "vti6") == 0) {
 152                                 p->proto = IPPROTO_IPV6;
 153                                 p->i_flags |= VTI_ISVTI;
 154                         } else if (strcmp(*argv, "ip/ipv6") == 0 ||
 155                                  strcmp(*argv, "ipv4/ipv6") == 0 ||
 156                                  strcmp(*argv, "ipip6") == 0 ||
 157                                  strcmp(*argv, "ip4ip6") == 0)
 158                                 p->proto = IPPROTO_IPIP;
 159                         else if (strcmp(*argv, "ip6gre") == 0 ||
 160                                  strcmp(*argv, "gre/ipv6") == 0)
 161                                 p->proto = IPPROTO_GRE;
 162                         else if (strcmp(*argv, "any/ipv6") == 0 ||
 163                                  strcmp(*argv, "any") == 0)
 164                                 p->proto = 0;
 165                         else {
 166                                 fprintf(stderr, "Unknown tunnel mode \"%s\"\n", *argv);
 167                                 exit(-1);
 168                         }
 169                 } else if (strcmp(*argv, "remote") == 0) {
 170                         inet_prefix raddr;
 171
 172                         NEXT_ARG();
 173                         get_prefix(&raddr, *argv, preferred_family);
 174                         if (raddr.family == AF_UNSPEC)
 175                                 invarg("\"remote\" address family is AF_UNSPEC", *argv);
 176                         memcpy(&p->raddr, &raddr.data, sizeof(p->raddr));
 177                 } else if (strcmp(*argv, "local") == 0) {
 178                         inet_prefix laddr;
 179
 180                         NEXT_ARG();
 181                         get_prefix(&laddr, *argv, preferred_family);
 182                         if (laddr.family == AF_UNSPEC)
 183                                 invarg("\"local\" address family is AF_UNSPEC", *argv);
 184                         memcpy(&p->laddr, &laddr.data, sizeof(p->laddr));
 185                 } else if (strcmp(*argv, "dev") == 0) {
 186                         NEXT_ARG();
 187                         medium = *argv;
 188                 } else if (strcmp(*argv, "encaplimit") == 0) {
 189                         NEXT_ARG();
 190                         if (strcmp(*argv, "none") == 0) {
 191                                 p->flags |= IP6_TNL_F_IGN_ENCAP_LIMIT;
 192                         } else {
 193                                 __u8 uval;
 194
 195                                 if (get_u8(&uval, *argv, 0) < -1)
 196                                         invarg("invalid ELIM", *argv);
 197                                 p->encap_limit = uval;
 198                                 p->flags &= ~IP6_TNL_F_IGN_ENCAP_LIMIT;
 199                         }
 200                 } else if (strcmp(*argv, "hoplimit") == 0 ||
 201                            strcmp(*argv, "ttl") == 0 ||
 202                            strcmp(*argv, "hlim") == 0) {
 203                         __u8 uval;
 204
 205                         NEXT_ARG();
 206                         if (get_u8(&uval, *argv, 0))
 207                                 invarg("invalid TTL", *argv);
 208                         p->hop_limit = uval;
 209                 } else if (strcmp(*argv, "tclass") == 0 ||
 210                            strcmp(*argv, "tc") == 0 ||
 211                            strcmp(*argv, "tos") == 0 ||
 212                            matches(*argv, "dsfield") == 0) {
 213                         __u8 uval;
 214
 215                         NEXT_ARG();
 216                         p->flowinfo &= ~IP6_FLOWINFO_TCLASS;
 217                         if (strcmp(*argv, "inherit") == 0)
 218                                 p->flags |= IP6_TNL_F_USE_ORIG_TCLASS;
 219                         else {
 220                                 if (get_u8(&uval, *argv, 16))
 221                                         invarg("invalid TClass", *argv);
 222                                 p->flowinfo |= htonl((__u32)uval << 20) & IP6_FLOWINFO_TCLASS;
 223                                 p->flags &= ~IP6_TNL_F_USE_ORIG_TCLASS;
 224                         }
 225                 } else if (strcmp(*argv, "flowlabel") == 0 ||
 226                            strcmp(*argv, "fl") == 0) {
 227                         __u32 uval;
 228
 229                         NEXT_ARG();
 230                         p->flowinfo &= ~IP6_FLOWINFO_FLOWLABEL;
 231                         if (strcmp(*argv, "inherit") == 0)
 232                                 p->flags |= IP6_TNL_F_USE_ORIG_FLOWLABEL;
 233                         else {
 234                                 if (get_u32(&uval, *argv, 16))
 235                                         invarg("invalid Flowlabel", *argv);
 236                                 if (uval > 0xFFFFF)
 237                                         invarg("invalid Flowlabel", *argv);
 238                                 p->flowinfo |= htonl(uval) & IP6_FLOWINFO_FLOWLABEL;
 239                                 p->flags &= ~IP6_TNL_F_USE_ORIG_FLOWLABEL;
 240                         }
 241                 } else if (strcmp(*argv, "dscp") == 0) {
 242                         NEXT_ARG();
 243                         if (strcmp(*argv, "inherit") != 0)
 244                                 invarg("not inherit", *argv);
 245                         p->flags |= IP6_TNL_F_RCV_DSCP_COPY;
 246                 } else if (strcmp(*argv, "allow-localremote") == 0) {
 247                         p->flags |= IP6_TNL_F_ALLOW_LOCAL_REMOTE;
 248                 } else if (strcmp(*argv, "noallow-localremote") == 0) {
 249                         p->flags &= ~IP6_TNL_F_ALLOW_LOCAL_REMOTE;
 250                 } else if (strcmp(*argv, "key") == 0) {
 251                         NEXT_ARG();
 252                         p->i_flags |= GRE_KEY;
 253                         p->o_flags |= GRE_KEY;
 254                         p->i_key = p->o_key = tnl_parse_key("key", *argv);
 255                 } else if (strcmp(*argv, "ikey") == 0) {
 256                         NEXT_ARG();
 257                         p->i_flags |= GRE_KEY;
 258                         p->i_key = tnl_parse_key("ikey", *argv);
 259                 } else if (strcmp(*argv, "okey") == 0) {
 260                         NEXT_ARG();
 261                         p->o_flags |= GRE_KEY;
 262                         p->o_key = tnl_parse_key("okey", *argv);
 263                 } else if (strcmp(*argv, "seq") == 0) {
 264                         p->i_flags |= GRE_SEQ;
 265                         p->o_flags |= GRE_SEQ;
 266                 } else if (strcmp(*argv, "iseq") == 0) {
 267                         p->i_flags |= GRE_SEQ;
 268                 } else if (strcmp(*argv, "oseq") == 0) {
 269                         p->o_flags |= GRE_SEQ;
 270                 } else if (strcmp(*argv, "csum") == 0) {
 271                         p->i_flags |= GRE_CSUM;
 272                         p->o_flags |= GRE_CSUM;
 273                 } else if (strcmp(*argv, "icsum") == 0) {
 274                         p->i_flags |= GRE_CSUM;
 275                 } else if (strcmp(*argv, "ocsum") == 0) {
 276                         p->o_flags |= GRE_CSUM;
 277                 } else {
 278                         if (strcmp(*argv, "name") == 0) {
 279                                 NEXT_ARG();
 280                         } else if (matches(*argv, "help") == 0)
 281                                 usage();
 282                         if (p->name[0])
 283                                 duparg2("name", *argv);
 284                         if (get_ifname(p->name, *argv))
 285                                 invarg("\"name\" not a valid ifname", *argv);
 286                         if (cmd == SIOCCHGTUNNEL && count == 0) {
 287                                 struct ip6_tnl_parm2 old_p = {};
 288
 289                                 if (tnl_get_ioctl(*argv, &old_p))
 290                                         return -1;
 291                                 *p = old_p;
 292                         }
 293                 }
 294                 count++;
 295                 argc--; argv++;
 296         }
 297         if (medium) {
 298                 p->link = ll_name_to_index(medium);
 299                 if (p->link == 0) {
 300                         fprintf(stderr, "Cannot find device \"%s\"\n", medium);
 301                         return -1;
 302                 }
 303         }
 304         return 0;
 305 }
 306
 307 static void ip6_tnl_parm_init(struct ip6_tnl_parm2 *p, int apply_default)
 308 {
 309         memset(p, 0, sizeof(*p));
 310         p->proto = IPPROTO_IPV6;
 311         if (apply_default) {
 312                 p->hop_limit = DEFAULT_TNL_HOP_LIMIT;
 313                 p->encap_limit = IPV6_DEFAULT_TNL_ENCAP_LIMIT;
 314         }
 315 }
 316
 317 /*
 318  * @p1: user specified parameter
 319  * @p2: database entry
 320  */
 321 static int ip6_tnl_parm_match(const struct ip6_tnl_parm2 *p1,
 322                               const struct ip6_tnl_parm2 *p2)
 323 {
 324         return ((!p1->link || p1->link == p2->link) &&
 325                 (!p1->name[0] || strcmp(p1->name, p2->name) == 0) &&
 326                 (IN6_IS_ADDR_UNSPECIFIED(&p1->laddr) ||
 327                  IN6_ARE_ADDR_EQUAL(&p1->laddr, &p2->laddr)) &&
 328                 (IN6_IS_ADDR_UNSPECIFIED(&p1->raddr) ||
 329                  IN6_ARE_ADDR_EQUAL(&p1->raddr, &p2->raddr)) &&
 330                 (!p1->proto || !p2->proto || p1->proto == p2->proto) &&
 331                 (!p1->encap_limit || p1->encap_limit == p2->encap_limit) &&
 332                 (!p1->hop_limit || p1->hop_limit == p2->hop_limit) &&
 333                 (!(p1->flowinfo & IP6_FLOWINFO_TCLASS) ||
 334                  !((p1->flowinfo ^ p2->flowinfo) & IP6_FLOWINFO_TCLASS)) &&
 335                 (!(p1->flowinfo & IP6_FLOWINFO_FLOWLABEL) ||
 336                  !((p1->flowinfo ^ p2->flowinfo) & IP6_FLOWINFO_FLOWLABEL)) &&
 337                 (!p1->flags || (p1->flags & p2->flags)));
 338 }
 339
 340 static int do_tunnels_list(struct ip6_tnl_parm2 *p)
 341 {
 342         char buf[512];
 343         int err = -1;
 344         FILE *fp = fopen("/proc/net/dev", "r");
 345
 346         if (fp == NULL) {
 347                 perror("fopen");
 348                 return -1;
 349         }
 350
 351         /* skip two lines at the begenning of the file */
 352         if (!fgets(buf, sizeof(buf), fp) ||
 353             !fgets(buf, sizeof(buf), fp)) {
 354                 fprintf(stderr, "/proc/net/dev read error\n");
 355                 goto end;
 356         }
 357
 358         while (fgets(buf, sizeof(buf), fp) != NULL) {
 359                 char name[IFNAMSIZ];
 360                 int index, type;
 361                 struct ip6_tnl_parm2 p1 = {};
 362                 char *ptr;
 363
 364                 buf[sizeof(buf) - 1] = '\0';
 365                 if ((ptr = strchr(buf, ':')) == NULL ||
 366                     (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) {
 367                         fprintf(stderr, "Wrong format for /proc/net/dev. Giving up.\n");
 368                         goto end;
 369                 }
 370                 if (p->name[0] && strcmp(p->name, name))
 371                         continue;
 372                 index = ll_name_to_index(name);
 373                 if (index == 0)
 374                         continue;
 375                 type = ll_index_to_type(index);
 376                 if (type == -1) {
 377                         fprintf(stderr, "Failed to get type of \"%s\"\n", name);
 378                         continue;
 379                 }
 380                 if (type != ARPHRD_TUNNEL6 && type != ARPHRD_IP6GRE)
 381                         continue;
 382                 ip6_tnl_parm_init(&p1, 0);
 383                 if (type == ARPHRD_IP6GRE)
 384                         p1.proto = IPPROTO_GRE;
 385                 strcpy(p1.name, name);
 386                 p1.link = ll_name_to_index(p1.name);
 387                 if (p1.link == 0)
 388                         continue;
 389                 if (tnl_get_ioctl(p1.name, &p1))
 390                         continue;
 391                 if (!ip6_tnl_parm_match(p, &p1))
 392                         continue;
 393                 print_tunnel(&p1);
 394                 if (show_stats)
 395                         tnl_print_stats(ptr);
 396                 printf("\n");
 397         }
 398         err = 0;
 399  end:
 400         fclose(fp);
 401         return err;
 402 }
 403
 404 static int do_show(int argc, char **argv)
 405 {
 406         struct ip6_tnl_parm2 p;
 407
 408         ll_init_map(&rth);
 409         ip6_tnl_parm_init(&p, 0);
 410         p.proto = 0;  /* default to any */
 411
 412         if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0)
 413                 return -1;
 414
 415         if (!p.name[0] || show_stats)
 416                 do_tunnels_list(&p);
 417         else {
 418                 if (tnl_get_ioctl(p.name, &p))
 419                         return -1;
 420                 print_tunnel(&p);
 421                 printf("\n");
 422         }
 423
 424         return 0;
 425 }
 426
 427 static int do_add(int cmd, int argc, char **argv)
 428 {
 429         struct ip6_tnl_parm2 p;
 430         const char *basedev = "ip6tnl0";
 431
 432         ip6_tnl_parm_init(&p, 1);
 433
 434         if (parse_args(argc, argv, cmd, &p) < 0)
 435                 return -1;
 436
 437         if (p.proto == IPPROTO_GRE)
 438                 basedev = "ip6gre0";
 439         else if (p.i_flags & VTI_ISVTI)
 440                 basedev = "ip6_vti0";
 441
 442         return tnl_add_ioctl(cmd, basedev, p.name, &p);
 443 }
 444
 445 static int do_del(int argc, char **argv)
 446 {
 447         struct ip6_tnl_parm2 p;
 448         const char *basedev = "ip6tnl0";
 449
 450         ip6_tnl_parm_init(&p, 1);
 451
 452         if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0)
 453                 return -1;
 454
 455         if (p.proto == IPPROTO_GRE)
 456                 basedev = "ip6gre0";
 457         else if (p.i_flags & VTI_ISVTI)
 458                 basedev = "ip6_vti0";
 459
 460         return tnl_del_ioctl(basedev, p.name, &p);
 461 }
 462
 463 int do_ip6tunnel(int argc, char **argv)
 464 {
 465         switch (preferred_family) {
 466         case AF_UNSPEC:
 467                 preferred_family = AF_INET6;
 468                 break;
 469         case AF_INET6:
 470                 break;
 471         default:
 472                 fprintf(stderr, "Unsupported protocol family: %d\n", preferred_family);
 473                 exit(-1);
 474         }
 475
 476         if (argc > 0) {
 477                 if (matches(*argv, "add") == 0)
 478                         return do_add(SIOCADDTUNNEL, argc - 1, argv + 1);
 479                 if (matches(*argv, "change") == 0)
 480                         return do_add(SIOCCHGTUNNEL, argc - 1, argv + 1);
 481                 if (matches(*argv, "delete") == 0)
 482                         return do_del(argc - 1, argv + 1);
 483                 if (matches(*argv, "show") == 0 ||
 484                     matches(*argv, "lst") == 0 ||
 485                     matches(*argv, "list") == 0)
 486                         return do_show(argc - 1, argv + 1);
 487                 if (matches(*argv, "help") == 0)
 488                         usage();
 489         } else
 490                 return do_show(0, NULL);
 491
 492         fprintf(stderr, "Command \"%s\" is unknown, try \"ip -f inet6 tunnel help\".\n", *argv);
 493         exit(-1);
 494 }