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