1/* 2 * iptunnel.c "ip tunnel" 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 10 * 11 */ 12 13#include <stdio.h> 14#include <stdlib.h> 15#include <string.h> 16#include <unistd.h> 17#include <sys/types.h> 18#include <sys/socket.h> 19#include <arpa/inet.h> 20#include <sys/ioctl.h> 21#include <net/if.h> 22#include <net/if_arp.h> 23#include <linux/ip.h> 24#include <linux/if_tunnel.h> 25 26#include "rt_names.h" 27#include "utils.h" 28#include "ip_common.h" 29#include "tunnel.h" 30 31static void usage(void) __attribute__((noreturn)); 32 33static void usage(void) 34{ 35 fprintf(stderr, "Usage: ip tunnel { add | change | del | show | prl | 6rd } [ NAME ]\n"); 36 fprintf(stderr, " [ mode { ipip | gre | sit | isatap | vti } ] [ remote ADDR ] [ local ADDR ]\n"); 37 fprintf(stderr, " [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n"); 38 fprintf(stderr, " [ prl-default ADDR ] [ prl-nodefault ADDR ] [ prl-delete ADDR ]\n"); 39 fprintf(stderr, " [ 6rd-prefix ADDR ] [ 6rd-relay_prefix ADDR ] [ 6rd-reset ]\n"); 40 fprintf(stderr, " [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [ dev PHYS_DEV ]\n"); 41 fprintf(stderr, "\n"); 42 fprintf(stderr, "Where: NAME := STRING\n"); 43 fprintf(stderr, " ADDR := { IP_ADDRESS | any }\n"); 44 fprintf(stderr, " TOS := { STRING | 00..ff | inherit | inherit/STRING | inherit/00..ff }\n"); 45 fprintf(stderr, " TTL := { 1..255 | inherit }\n"); 46 fprintf(stderr, " KEY := { DOTTED_QUAD | NUMBER }\n"); 47 exit(-1); 48} 49 50static void set_tunnel_proto(struct ip_tunnel_parm *p, int proto) 51{ 52 if (p->iph.protocol && p->iph.protocol != proto) { 53 fprintf(stderr, 54 "You managed to ask for more than one tunnel mode.\n"); 55 exit(-1); 56 } 57 p->iph.protocol = proto; 58} 59 60static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p) 61{ 62 int count = 0; 63 const char *medium = NULL; 64 int isatap = 0; 65 66 memset(p, 0, sizeof(*p)); 67 p->iph.version = 4; 68 p->iph.ihl = 5; 69#ifndef IP_DF 70#define IP_DF 0x4000 /* Flag: "Don't Fragment" */ 71#endif 72 p->iph.frag_off = htons(IP_DF); 73 74 while (argc > 0) { 75 if (strcmp(*argv, "mode") == 0) { 76 NEXT_ARG(); 77 if (strcmp(*argv, "ipip") == 0 || 78 strcmp(*argv, "ip/ip") == 0) { 79 set_tunnel_proto(p, IPPROTO_IPIP); 80 } else if (strcmp(*argv, "gre") == 0 || 81 strcmp(*argv, "gre/ip") == 0) { 82 set_tunnel_proto(p, IPPROTO_GRE); 83 } else if (strcmp(*argv, "sit") == 0 || 84 strcmp(*argv, "ipv6/ip") == 0) { 85 set_tunnel_proto(p, IPPROTO_IPV6); 86 } else if (strcmp(*argv, "isatap") == 0) { 87 set_tunnel_proto(p, IPPROTO_IPV6); 88 isatap++; 89 } else if (strcmp(*argv, "vti") == 0) { 90 set_tunnel_proto(p, IPPROTO_IPIP); 91 p->i_flags |= VTI_ISVTI; 92 } else { 93 fprintf(stderr, 94 "Unknown tunnel mode \"%s\"\n", *argv); 95 exit(-1); 96 } 97 } else if (strcmp(*argv, "key") == 0) { 98 NEXT_ARG(); 99 p->i_flags |= GRE_KEY; 100 p->o_flags |= GRE_KEY; 101 p->i_key = p->o_key = tnl_parse_key("key", *argv); 102 } else if (strcmp(*argv, "ikey") == 0) { 103 NEXT_ARG(); 104 p->i_flags |= GRE_KEY; 105 p->i_key = tnl_parse_key("ikey", *argv); 106 } else if (strcmp(*argv, "okey") == 0) { 107 NEXT_ARG(); 108 p->o_flags |= GRE_KEY; 109 p->o_key = tnl_parse_key("okey", *argv); 110 } else if (strcmp(*argv, "seq") == 0) { 111 p->i_flags |= GRE_SEQ; 112 p->o_flags |= GRE_SEQ; 113 } else if (strcmp(*argv, "iseq") == 0) { 114 p->i_flags |= GRE_SEQ; 115 } else if (strcmp(*argv, "oseq") == 0) { 116 p->o_flags |= GRE_SEQ; 117 } else if (strcmp(*argv, "csum") == 0) { 118 p->i_flags |= GRE_CSUM; 119 p->o_flags |= GRE_CSUM; 120 } else if (strcmp(*argv, "icsum") == 0) { 121 p->i_flags |= GRE_CSUM; 122 } else if (strcmp(*argv, "ocsum") == 0) { 123 p->o_flags |= GRE_CSUM; 124 } else if (strcmp(*argv, "nopmtudisc") == 0) { 125 p->iph.frag_off = 0; 126 } else if (strcmp(*argv, "pmtudisc") == 0) { 127 p->iph.frag_off = htons(IP_DF); 128 } else if (strcmp(*argv, "remote") == 0) { 129 NEXT_ARG(); 130 if (strcmp(*argv, "any")) 131 p->iph.daddr = get_addr32(*argv); 132 else 133 p->iph.daddr = htonl(INADDR_ANY); 134 } else if (strcmp(*argv, "local") == 0) { 135 NEXT_ARG(); 136 if (strcmp(*argv, "any")) 137 p->iph.saddr = get_addr32(*argv); 138 else 139 p->iph.saddr = htonl(INADDR_ANY); 140 } else if (strcmp(*argv, "dev") == 0) { 141 NEXT_ARG(); 142 medium = *argv; 143 } else if (strcmp(*argv, "ttl") == 0 || 144 strcmp(*argv, "hoplimit") == 0 || 145 strcmp(*argv, "hlim") == 0) { 146 __u8 uval; 147 148 NEXT_ARG(); 149 if (strcmp(*argv, "inherit") != 0) { 150 if (get_u8(&uval, *argv, 0)) 151 invarg("invalid TTL\n", *argv); 152 p->iph.ttl = uval; 153 } 154 } else if (strcmp(*argv, "tos") == 0 || 155 strcmp(*argv, "tclass") == 0 || 156 matches(*argv, "dsfield") == 0) { 157 char *dsfield; 158 __u32 uval; 159 160 NEXT_ARG(); 161 dsfield = *argv; 162 strsep(&dsfield, "/"); 163 if (strcmp(*argv, "inherit") != 0) { 164 dsfield = *argv; 165 p->iph.tos = 0; 166 } else 167 p->iph.tos = 1; 168 if (dsfield) { 169 if (rtnl_dsfield_a2n(&uval, dsfield)) 170 invarg("bad TOS value", *argv); 171 p->iph.tos |= uval; 172 } 173 } else { 174 if (strcmp(*argv, "name") == 0) 175 NEXT_ARG(); 176 else if (matches(*argv, "help") == 0) 177 usage(); 178 179 if (p->name[0]) 180 duparg2("name", *argv); 181 if (get_ifname(p->name, *argv)) 182 invarg("\"name\" not a valid ifname", *argv); 183 if (cmd == SIOCCHGTUNNEL && count == 0) { 184 struct ip_tunnel_parm old_p = {}; 185 186 if (tnl_get_ioctl(*argv, &old_p)) 187 return -1; 188 *p = old_p; 189 } 190 } 191 count++; 192 argc--; argv++; 193 } 194 195 196 if (p->iph.protocol == 0) { 197 if (memcmp(p->name, "gre", 3) == 0) 198 p->iph.protocol = IPPROTO_GRE; 199 else if (memcmp(p->name, "ipip", 4) == 0) 200 p->iph.protocol = IPPROTO_IPIP; 201 else if (memcmp(p->name, "sit", 3) == 0) 202 p->iph.protocol = IPPROTO_IPV6; 203 else if (memcmp(p->name, "isatap", 6) == 0) { 204 p->iph.protocol = IPPROTO_IPV6; 205 isatap++; 206 } else if (memcmp(p->name, "vti", 3) == 0) { 207 p->iph.protocol = IPPROTO_IPIP; 208 p->i_flags |= VTI_ISVTI; 209 } 210 } 211 212 if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) { 213 if (!(p->i_flags & VTI_ISVTI) && 214 (p->iph.protocol != IPPROTO_GRE)) { 215 fprintf(stderr, "Keys are not allowed with ipip and sit tunnels\n"); 216 return -1; 217 } 218 } 219 220 if (medium) { 221 p->link = ll_name_to_index(medium); 222 if (p->link == 0) { 223 fprintf(stderr, "Cannot find device \"%s\"\n", medium); 224 return -1; 225 } 226 } 227 228 if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) { 229 p->i_key = p->iph.daddr; 230 p->i_flags |= GRE_KEY; 231 } 232 if (p->o_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) { 233 p->o_key = p->iph.daddr; 234 p->o_flags |= GRE_KEY; 235 } 236 if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) { 237 fprintf(stderr, "A broadcast tunnel requires a source address\n"); 238 return -1; 239 } 240 if (isatap) 241 p->i_flags |= SIT_ISATAP; 242 243 return 0; 244} 245 246static const char *tnl_defname(const struct ip_tunnel_parm *p) 247{ 248 switch (p->iph.protocol) { 249 case IPPROTO_IPIP: 250 if (p->i_flags & VTI_ISVTI) 251 return "ip_vti0"; 252 else 253 return "tunl0"; 254 case IPPROTO_GRE: 255 return "gre0"; 256 case IPPROTO_IPV6: 257 return "sit0"; 258 } 259 return NULL; 260} 261 262static int do_add(int cmd, int argc, char **argv) 263{ 264 struct ip_tunnel_parm p; 265 const char *basedev; 266 267 if (parse_args(argc, argv, cmd, &p) < 0) 268 return -1; 269 270 if (p.iph.ttl && p.iph.frag_off == 0) { 271 fprintf(stderr, "ttl != 0 and nopmtudisc are incompatible\n"); 272 return -1; 273 } 274 275 basedev = tnl_defname(&p); 276 if (!basedev) { 277 fprintf(stderr, 278 "cannot determine tunnel mode (ipip, gre, vti or sit)\n"); 279 return -1; 280 } 281 282 return tnl_add_ioctl(cmd, basedev, p.name, &p); 283} 284 285static int do_del(int argc, char **argv) 286{ 287 struct ip_tunnel_parm p; 288 289 if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0) 290 return -1; 291 292 return tnl_del_ioctl(tnl_defname(&p) ? : p.name, p.name, &p); 293} 294 295static void print_tunnel(struct ip_tunnel_parm *p) 296{ 297 struct ip_tunnel_6rd ip6rd = {}; 298 char s1[1024]; 299 char s2[1024]; 300 301 /* Do not use format_host() for local addr, 302 * symbolic name will not be useful. 303 */ 304 printf("%s: %s/ip remote %s local %s", 305 p->name, 306 tnl_strproto(p->iph.protocol), 307 p->iph.daddr ? format_host_r(AF_INET, 4, &p->iph.daddr, s1, sizeof(s1)) : "any", 308 p->iph.saddr ? rt_addr_n2a_r(AF_INET, 4, &p->iph.saddr, s2, sizeof(s2)) : "any"); 309 310 if (p->iph.protocol == IPPROTO_IPV6 && (p->i_flags & SIT_ISATAP)) { 311 struct ip_tunnel_prl prl[16] = {}; 312 int i; 313 314 prl[0].datalen = sizeof(prl) - sizeof(prl[0]); 315 prl[0].addr = htonl(INADDR_ANY); 316 317 if (!tnl_prl_ioctl(SIOCGETPRL, p->name, prl)) 318 for (i = 1; i < ARRAY_SIZE(prl); i++) { 319 if (prl[i].addr != htonl(INADDR_ANY)) { 320 printf(" %s %s ", 321 (prl[i].flags & PRL_DEFAULT) ? "pdr" : "pr", 322 format_host(AF_INET, 4, &prl[i].addr)); 323 } 324 } 325 } 326 327 if (p->link) { 328 const char *n = ll_index_to_name(p->link); 329 330 if (n) 331 printf(" dev %s", n); 332 } 333 334 if (p->iph.ttl) 335 printf(" ttl %d", p->iph.ttl); 336 else 337 printf(" ttl inherit"); 338 339 if (p->iph.tos) { 340 SPRINT_BUF(b1); 341 printf(" tos"); 342 if (p->iph.tos & 1) 343 printf(" inherit"); 344 if (p->iph.tos & ~1) 345 printf("%c%s ", p->iph.tos & 1 ? '/' : ' ', 346 rtnl_dsfield_n2a(p->iph.tos & ~1, b1, sizeof(b1))); 347 } 348 349 if (!(p->iph.frag_off & htons(IP_DF))) 350 printf(" nopmtudisc"); 351 352 if (p->iph.protocol == IPPROTO_IPV6 && !tnl_ioctl_get_6rd(p->name, &ip6rd) && ip6rd.prefixlen) { 353 printf(" 6rd-prefix %s/%u", 354 inet_ntop(AF_INET6, &ip6rd.prefix, s1, sizeof(s1)), 355 ip6rd.prefixlen); 356 if (ip6rd.relay_prefix) { 357 printf(" 6rd-relay_prefix %s/%u", 358 format_host(AF_INET, 4, &ip6rd.relay_prefix), 359 ip6rd.relay_prefixlen); 360 } 361 } 362 363 if ((p->i_flags & GRE_KEY) && (p->o_flags & GRE_KEY) && p->o_key == p->i_key) 364 printf(" key %u", ntohl(p->i_key)); 365 else if ((p->i_flags | p->o_flags) & GRE_KEY) { 366 if (p->i_flags & GRE_KEY) 367 printf(" ikey %u", ntohl(p->i_key)); 368 if (p->o_flags & GRE_KEY) 369 printf(" okey %u", ntohl(p->o_key)); 370 } 371 372 if (p->i_flags & GRE_SEQ) 373 printf("%s Drop packets out of sequence.", _SL_); 374 if (p->i_flags & GRE_CSUM) 375 printf("%s Checksum in received packet is required.", _SL_); 376 if (p->o_flags & GRE_SEQ) 377 printf("%s Sequence packets on output.", _SL_); 378 if (p->o_flags & GRE_CSUM) 379 printf("%s Checksum output packets.", _SL_); 380} 381 382static int do_tunnels_list(struct ip_tunnel_parm *p) 383{ 384 char buf[512]; 385 int err = -1; 386 FILE *fp = fopen("/proc/net/dev", "r"); 387 388 if (fp == NULL) { 389 perror("fopen"); 390 return -1; 391 } 392 393 /* skip header lines */ 394 if (!fgets(buf, sizeof(buf), fp) || 395 !fgets(buf, sizeof(buf), fp)) { 396 fprintf(stderr, "/proc/net/dev read error\n"); 397 goto end; 398 } 399 400 while (fgets(buf, sizeof(buf), fp) != NULL) { 401 char name[IFNAMSIZ]; 402 int index, type; 403 struct ip_tunnel_parm p1 = {}; 404 char *ptr; 405 406 buf[sizeof(buf) - 1] = 0; 407 ptr = strchr(buf, ':'); 408 if (ptr == NULL || 409 (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) { 410 fprintf(stderr, "Wrong format for /proc/net/dev. Giving up.\n"); 411 goto end; 412 } 413 if (p->name[0] && strcmp(p->name, name)) 414 continue; 415 index = ll_name_to_index(name); 416 if (index == 0) 417 continue; 418 type = ll_index_to_type(index); 419 if (type == -1) { 420 fprintf(stderr, "Failed to get type of \"%s\"\n", name); 421 continue; 422 } 423 if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT) 424 continue; 425 if (tnl_get_ioctl(name, &p1)) 426 continue; 427 if ((p->link && p1.link != p->link) || 428 (p->name[0] && strcmp(p1.name, p->name)) || 429 (p->iph.daddr && p1.iph.daddr != p->iph.daddr) || 430 (p->iph.saddr && p1.iph.saddr != p->iph.saddr) || 431 (p->i_key && p1.i_key != p->i_key)) 432 continue; 433 print_tunnel(&p1); 434 if (show_stats) 435 tnl_print_stats(ptr); 436 printf("\n"); 437 } 438 err = 0; 439 end: 440 fclose(fp); 441 return err; 442} 443 444static int do_show(int argc, char **argv) 445{ 446 struct ip_tunnel_parm p; 447 const char *basedev; 448 449 ll_init_map(&rth); 450 if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0) 451 return -1; 452 453 basedev = tnl_defname(&p); 454 if (!basedev) 455 return do_tunnels_list(&p); 456 457 if (tnl_get_ioctl(p.name[0] ? p.name : basedev, &p)) 458 return -1; 459 460 print_tunnel(&p); 461 printf("\n"); 462 return 0; 463} 464 465static int do_prl(int argc, char **argv) 466{ 467 struct ip_tunnel_prl p = {}; 468 int count = 0; 469 int cmd = 0; 470 const char *medium = NULL; 471 472 while (argc > 0) { 473 if (strcmp(*argv, "prl-default") == 0) { 474 NEXT_ARG(); 475 cmd = SIOCADDPRL; 476 p.addr = get_addr32(*argv); 477 p.flags |= PRL_DEFAULT; 478 count++; 479 } else if (strcmp(*argv, "prl-nodefault") == 0) { 480 NEXT_ARG(); 481 cmd = SIOCADDPRL; 482 p.addr = get_addr32(*argv); 483 count++; 484 } else if (strcmp(*argv, "prl-delete") == 0) { 485 NEXT_ARG(); 486 cmd = SIOCDELPRL; 487 p.addr = get_addr32(*argv); 488 count++; 489 } else if (strcmp(*argv, "dev") == 0) { 490 NEXT_ARG(); 491 if (check_ifname(*argv)) 492 invarg("\"dev\" not a valid ifname", *argv); 493 medium = *argv; 494 } else { 495 fprintf(stderr, 496 "Invalid PRL parameter \"%s\"\n", *argv); 497 exit(-1); 498 } 499 if (count > 1) { 500 fprintf(stderr, 501 "One PRL entry at a time\n"); 502 exit(-1); 503 } 504 argc--; argv++; 505 } 506 if (!medium) { 507 fprintf(stderr, "Must specify device\n"); 508 exit(-1); 509 } 510 511 return tnl_prl_ioctl(cmd, medium, &p); 512} 513 514static int do_6rd(int argc, char **argv) 515{ 516 struct ip_tunnel_6rd ip6rd = {}; 517 int cmd = 0; 518 const char *medium = NULL; 519 inet_prefix prefix; 520 521 while (argc > 0) { 522 if (strcmp(*argv, "6rd-prefix") == 0) { 523 NEXT_ARG(); 524 if (get_prefix(&prefix, *argv, AF_INET6)) 525 invarg("invalid 6rd_prefix\n", *argv); 526 cmd = SIOCADD6RD; 527 memcpy(&ip6rd.prefix, prefix.data, 16); 528 ip6rd.prefixlen = prefix.bitlen; 529 } else if (strcmp(*argv, "6rd-relay_prefix") == 0) { 530 NEXT_ARG(); 531 if (get_prefix(&prefix, *argv, AF_INET)) 532 invarg("invalid 6rd-relay_prefix\n", *argv); 533 cmd = SIOCADD6RD; 534 memcpy(&ip6rd.relay_prefix, prefix.data, 4); 535 ip6rd.relay_prefixlen = prefix.bitlen; 536 } else if (strcmp(*argv, "6rd-reset") == 0) { 537 cmd = SIOCDEL6RD; 538 } else if (strcmp(*argv, "dev") == 0) { 539 NEXT_ARG(); 540 if (check_ifname(*argv)) 541 invarg("\"dev\" not a valid ifname", *argv); 542 medium = *argv; 543 } else { 544 fprintf(stderr, 545 "Invalid 6RD parameter \"%s\"\n", *argv); 546 exit(-1); 547 } 548 argc--; argv++; 549 } 550 if (!medium) { 551 fprintf(stderr, "Must specify device\n"); 552 exit(-1); 553 } 554 555 return tnl_6rd_ioctl(cmd, medium, &ip6rd); 556} 557 558static int tunnel_mode_is_ipv6(char *tunnel_mode) 559{ 560 static const char * const ipv6_modes[] = { 561 "ipv6/ipv6", "ip6ip6", 562 "vti6", 563 "ip/ipv6", "ipv4/ipv6", "ipip6", "ip4ip6", 564 "ip6gre", "gre/ipv6", 565 "any/ipv6", "any" 566 }; 567 int i; 568 569 for (i = 0; i < ARRAY_SIZE(ipv6_modes); i++) { 570 if (strcmp(ipv6_modes[i], tunnel_mode) == 0) 571 return 1; 572 } 573 return 0; 574} 575 576int do_iptunnel(int argc, char **argv) 577{ 578 int i; 579 580 for (i = 0; i < argc - 1; i++) { 581 if (strcmp(argv[i], "mode") == 0) { 582 if (tunnel_mode_is_ipv6(argv[i + 1])) 583 preferred_family = AF_INET6; 584 break; 585 } 586 } 587 switch (preferred_family) { 588 case AF_UNSPEC: 589 preferred_family = AF_INET; 590 break; 591 case AF_INET: 592 break; 593 /* 594 * This is silly enough but we have no easy way to make it 595 * protocol-independent because of unarranged structure between 596 * IPv4 and IPv6. 597 */ 598 case AF_INET6: 599 return do_ip6tunnel(argc, argv); 600 default: 601 fprintf(stderr, "Unsupported protocol family: %d\n", preferred_family); 602 exit(-1); 603 } 604 605 if (argc > 0) { 606 if (matches(*argv, "add") == 0) 607 return do_add(SIOCADDTUNNEL, argc - 1, argv + 1); 608 if (matches(*argv, "change") == 0) 609 return do_add(SIOCCHGTUNNEL, argc - 1, argv + 1); 610 if (matches(*argv, "delete") == 0) 611 return do_del(argc - 1, argv + 1); 612 if (matches(*argv, "show") == 0 || 613 matches(*argv, "lst") == 0 || 614 matches(*argv, "list") == 0) 615 return do_show(argc - 1, argv + 1); 616 if (matches(*argv, "prl") == 0) 617 return do_prl(argc - 1, argv + 1); 618 if (matches(*argv, "6rd") == 0) 619 return do_6rd(argc - 1, argv + 1); 620 if (matches(*argv, "help") == 0) 621 usage(); 622 } else 623 return do_show(0, NULL); 624 625 fprintf(stderr, "Command \"%s\" is unknown, try \"ip tunnel help\"\n", *argv); 626 exit(-1); 627} 628