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