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 (at) 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 31 static void usage(void) __attribute__((noreturn)); 32 33 static 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 50 static 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 60 static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p) 61 { 62 int count = 0; 63 char medium[IFNAMSIZ]; 64 int isatap = 0; 65 66 memset(p, 0, sizeof(*p)); 67 memset(&medium, 0, sizeof(medium)); 68 69 p->iph.version = 4; 70 p->iph.ihl = 5; 71 #ifndef IP_DF 72 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */ 73 #endif 74 p->iph.frag_off = htons(IP_DF); 75 76 while (argc > 0) { 77 if (strcmp(*argv, "mode") == 0) { 78 NEXT_ARG(); 79 if (strcmp(*argv, "ipip") == 0 || 80 strcmp(*argv, "ip/ip") == 0) { 81 set_tunnel_proto(p, IPPROTO_IPIP); 82 } else if (strcmp(*argv, "gre") == 0 || 83 strcmp(*argv, "gre/ip") == 0) { 84 set_tunnel_proto(p, IPPROTO_GRE); 85 } else if (strcmp(*argv, "sit") == 0 || 86 strcmp(*argv, "ipv6/ip") == 0) { 87 set_tunnel_proto(p, IPPROTO_IPV6); 88 } else if (strcmp(*argv, "isatap") == 0) { 89 set_tunnel_proto(p, IPPROTO_IPV6); 90 isatap++; 91 } else if (strcmp(*argv, "vti") == 0) { 92 set_tunnel_proto(p, IPPROTO_IPIP); 93 p->i_flags |= VTI_ISVTI; 94 } else { 95 fprintf(stderr, 96 "Unknown tunnel mode \"%s\"\n", *argv); 97 exit(-1); 98 } 99 } else if (strcmp(*argv, "key") == 0) { 100 NEXT_ARG(); 101 p->i_flags |= GRE_KEY; 102 p->o_flags |= GRE_KEY; 103 p->i_key = p->o_key = tnl_parse_key("key", *argv); 104 } else if (strcmp(*argv, "ikey") == 0) { 105 NEXT_ARG(); 106 p->i_flags |= GRE_KEY; 107 p->i_key = tnl_parse_key("ikey", *argv); 108 } else if (strcmp(*argv, "okey") == 0) { 109 NEXT_ARG(); 110 p->o_flags |= GRE_KEY; 111 p->o_key = tnl_parse_key("okey", *argv); 112 } else if (strcmp(*argv, "seq") == 0) { 113 p->i_flags |= GRE_SEQ; 114 p->o_flags |= GRE_SEQ; 115 } else if (strcmp(*argv, "iseq") == 0) { 116 p->i_flags |= GRE_SEQ; 117 } else if (strcmp(*argv, "oseq") == 0) { 118 p->o_flags |= GRE_SEQ; 119 } else if (strcmp(*argv, "csum") == 0) { 120 p->i_flags |= GRE_CSUM; 121 p->o_flags |= GRE_CSUM; 122 } else if (strcmp(*argv, "icsum") == 0) { 123 p->i_flags |= GRE_CSUM; 124 } else if (strcmp(*argv, "ocsum") == 0) { 125 p->o_flags |= GRE_CSUM; 126 } else if (strcmp(*argv, "nopmtudisc") == 0) { 127 p->iph.frag_off = 0; 128 } else if (strcmp(*argv, "pmtudisc") == 0) { 129 p->iph.frag_off = htons(IP_DF); 130 } else if (strcmp(*argv, "remote") == 0) { 131 NEXT_ARG(); 132 if (strcmp(*argv, "any")) 133 p->iph.daddr = get_addr32(*argv); 134 else 135 p->iph.daddr = htonl(INADDR_ANY); 136 } else if (strcmp(*argv, "local") == 0) { 137 NEXT_ARG(); 138 if (strcmp(*argv, "any")) 139 p->iph.saddr = get_addr32(*argv); 140 else 141 p->iph.saddr = htonl(INADDR_ANY); 142 } else if (strcmp(*argv, "dev") == 0) { 143 NEXT_ARG(); 144 strncpy(medium, *argv, IFNAMSIZ - 1); 145 } else if (strcmp(*argv, "ttl") == 0 || 146 strcmp(*argv, "hoplimit") == 0 || 147 strcmp(*argv, "hlim") == 0) { 148 __u8 uval; 149 150 NEXT_ARG(); 151 if (strcmp(*argv, "inherit") != 0) { 152 if (get_u8(&uval, *argv, 0)) 153 invarg("invalid TTL\n", *argv); 154 p->iph.ttl = uval; 155 } 156 } else if (strcmp(*argv, "tos") == 0 || 157 strcmp(*argv, "tclass") == 0 || 158 matches(*argv, "dsfield") == 0) { 159 char *dsfield; 160 __u32 uval; 161 162 NEXT_ARG(); 163 dsfield = *argv; 164 strsep(&dsfield, "/"); 165 if (strcmp(*argv, "inherit") != 0) { 166 dsfield = *argv; 167 p->iph.tos = 0; 168 } else 169 p->iph.tos = 1; 170 if (dsfield) { 171 if (rtnl_dsfield_a2n(&uval, dsfield)) 172 invarg("bad TOS value", *argv); 173 p->iph.tos |= uval; 174 } 175 } else { 176 if (strcmp(*argv, "name") == 0) 177 NEXT_ARG(); 178 else if (matches(*argv, "help") == 0) 179 usage(); 180 181 if (p->name[0]) 182 duparg2("name", *argv); 183 strncpy(p->name, *argv, IFNAMSIZ - 1); 184 if (cmd == SIOCCHGTUNNEL && count == 0) { 185 struct ip_tunnel_parm old_p; 186 187 memset(&old_p, 0, sizeof(old_p)); 188 if (tnl_get_ioctl(*argv, &old_p)) 189 return -1; 190 *p = old_p; 191 } 192 } 193 count++; 194 argc--; argv++; 195 } 196 197 198 if (p->iph.protocol == 0) { 199 if (memcmp(p->name, "gre", 3) == 0) 200 p->iph.protocol = IPPROTO_GRE; 201 else if (memcmp(p->name, "ipip", 4) == 0) 202 p->iph.protocol = IPPROTO_IPIP; 203 else if (memcmp(p->name, "sit", 3) == 0) 204 p->iph.protocol = IPPROTO_IPV6; 205 else if (memcmp(p->name, "isatap", 6) == 0) { 206 p->iph.protocol = IPPROTO_IPV6; 207 isatap++; 208 } else if (memcmp(p->name, "vti", 3) == 0) { 209 p->iph.protocol = IPPROTO_IPIP; 210 p->i_flags |= VTI_ISVTI; 211 } 212 } 213 214 if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) { 215 if (!(p->i_flags & VTI_ISVTI) && 216 (p->iph.protocol != IPPROTO_GRE)) { 217 fprintf(stderr, "Keys are not allowed with ipip and sit tunnels\n"); 218 return -1; 219 } 220 } 221 222 if (medium[0]) { 223 p->link = ll_name_to_index(medium); 224 if (p->link == 0) { 225 fprintf(stderr, "Cannot find device \"%s\"\n", medium); 226 return -1; 227 } 228 } 229 230 if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) { 231 p->i_key = p->iph.daddr; 232 p->i_flags |= GRE_KEY; 233 } 234 if (p->o_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) { 235 p->o_key = p->iph.daddr; 236 p->o_flags |= GRE_KEY; 237 } 238 if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) { 239 fprintf(stderr, "A broadcast tunnel requires a source address\n"); 240 return -1; 241 } 242 if (isatap) 243 p->i_flags |= SIT_ISATAP; 244 245 return 0; 246 } 247 248 static const char *tnl_defname(const struct ip_tunnel_parm *p) 249 { 250 switch (p->iph.protocol) { 251 case IPPROTO_IPIP: 252 if (p->i_flags & VTI_ISVTI) 253 return "ip_vti0"; 254 else 255 return "tunl0"; 256 case IPPROTO_GRE: 257 return "gre0"; 258 case IPPROTO_IPV6: 259 return "sit0"; 260 } 261 return NULL; 262 } 263 264 static int do_add(int cmd, int argc, char **argv) 265 { 266 struct ip_tunnel_parm p; 267 const char *basedev; 268 269 if (parse_args(argc, argv, cmd, &p) < 0) 270 return -1; 271 272 if (p.iph.ttl && p.iph.frag_off == 0) { 273 fprintf(stderr, "ttl != 0 and nopmtudisc are incompatible\n"); 274 return -1; 275 } 276 277 basedev = tnl_defname(&p); 278 if (!basedev) { 279 fprintf(stderr, 280 "cannot determine tunnel mode (ipip, gre, vti or sit)\n"); 281 return -1; 282 } 283 284 return tnl_add_ioctl(cmd, basedev, p.name, &p); 285 } 286 287 static int do_del(int argc, char **argv) 288 { 289 struct ip_tunnel_parm p; 290 291 if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0) 292 return -1; 293 294 return tnl_del_ioctl(tnl_defname(&p) ? : p.name, p.name, &p); 295 } 296 297 static void print_tunnel(struct ip_tunnel_parm *p) 298 { 299 struct ip_tunnel_6rd ip6rd; 300 char s1[1024]; 301 char s2[1024]; 302 303 memset(&ip6rd, 0, sizeof(ip6rd)); 304 305 /* Do not use format_host() for local addr, 306 * symbolic name will not be useful. 307 */ 308 printf("%s: %s/ip remote %s local %s", 309 p->name, 310 tnl_strproto(p->iph.protocol), 311 p->iph.daddr ? format_host(AF_INET, 4, &p->iph.daddr, s1, sizeof(s1)) : "any", 312 p->iph.saddr ? rt_addr_n2a(AF_INET, 4, &p->iph.saddr, s2, sizeof(s2)) : "any"); 313 314 if (p->iph.protocol == IPPROTO_IPV6 && (p->i_flags & SIT_ISATAP)) { 315 struct ip_tunnel_prl prl[16]; 316 int i; 317 318 memset(prl, 0, sizeof(prl)); 319 prl[0].datalen = sizeof(prl) - sizeof(prl[0]); 320 prl[0].addr = htonl(INADDR_ANY); 321 322 if (!tnl_prl_ioctl(SIOCGETPRL, p->name, prl)) 323 for (i = 1; i < ARRAY_SIZE(prl); i++) { 324 if (prl[i].addr != htonl(INADDR_ANY)) { 325 printf(" %s %s ", 326 (prl[i].flags & PRL_DEFAULT) ? "pdr" : "pr", 327 format_host(AF_INET, 4, &prl[i].addr, s1, sizeof(s1))); 328 } 329 } 330 } 331 332 if (p->link) { 333 const char *n = ll_index_to_name(p->link); 334 335 if (n) 336 printf(" dev %s", n); 337 } 338 339 if (p->iph.ttl) 340 printf(" ttl %d", p->iph.ttl); 341 else 342 printf(" ttl inherit"); 343 344 if (p->iph.tos) { 345 SPRINT_BUF(b1); 346 printf(" tos"); 347 if (p->iph.tos & 1) 348 printf(" inherit"); 349 if (p->iph.tos & ~1) 350 printf("%c%s ", p->iph.tos & 1 ? '/' : ' ', 351 rtnl_dsfield_n2a(p->iph.tos & ~1, b1, sizeof(b1))); 352 } 353 354 if (!(p->iph.frag_off & htons(IP_DF))) 355 printf(" nopmtudisc"); 356 357 if (p->iph.protocol == IPPROTO_IPV6 && !tnl_ioctl_get_6rd(p->name, &ip6rd) && ip6rd.prefixlen) { 358 printf(" 6rd-prefix %s/%u", 359 inet_ntop(AF_INET6, &ip6rd.prefix, s1, sizeof(s1)), 360 ip6rd.prefixlen); 361 if (ip6rd.relay_prefix) { 362 printf(" 6rd-relay_prefix %s/%u", 363 format_host(AF_INET, 4, &ip6rd.relay_prefix, s1, sizeof(s1)), 364 ip6rd.relay_prefixlen); 365 } 366 } 367 368 if ((p->i_flags & GRE_KEY) && (p->o_flags & GRE_KEY) && p->o_key == p->i_key) 369 printf(" key %u", ntohl(p->i_key)); 370 else if ((p->i_flags | p->o_flags) & GRE_KEY) { 371 if (p->i_flags & GRE_KEY) 372 printf(" ikey %u", ntohl(p->i_key)); 373 if (p->o_flags & GRE_KEY) 374 printf(" okey %u", ntohl(p->o_key)); 375 } 376 377 if (p->i_flags & GRE_SEQ) 378 printf("%s Drop packets out of sequence.", _SL_); 379 if (p->i_flags & GRE_CSUM) 380 printf("%s Checksum in received packet is required.", _SL_); 381 if (p->o_flags & GRE_SEQ) 382 printf("%s Sequence packets on output.", _SL_); 383 if (p->o_flags & GRE_CSUM) 384 printf("%s Checksum output packets.", _SL_); 385 } 386 387 static int do_tunnels_list(struct ip_tunnel_parm *p) 388 { 389 char buf[512]; 390 int err = -1; 391 FILE *fp = fopen("/proc/net/dev", "r"); 392 393 if (fp == NULL) { 394 perror("fopen"); 395 return -1; 396 } 397 398 /* skip header lines */ 399 if (!fgets(buf, sizeof(buf), fp) || 400 !fgets(buf, sizeof(buf), fp)) { 401 fprintf(stderr, "/proc/net/dev read error\n"); 402 goto end; 403 } 404 405 while (fgets(buf, sizeof(buf), fp) != NULL) { 406 char name[IFNAMSIZ]; 407 int index, type; 408 struct ip_tunnel_parm p1; 409 char *ptr; 410 411 buf[sizeof(buf) - 1] = 0; 412 ptr = strchr(buf, ':'); 413 if (ptr == NULL || 414 (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) { 415 fprintf(stderr, "Wrong format for /proc/net/dev. Giving up.\n"); 416 goto end; 417 } 418 if (p->name[0] && strcmp(p->name, name)) 419 continue; 420 index = ll_name_to_index(name); 421 if (index == 0) 422 continue; 423 type = ll_index_to_type(index); 424 if (type == -1) { 425 fprintf(stderr, "Failed to get type of \"%s\"\n", name); 426 continue; 427 } 428 if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT) 429 continue; 430 memset(&p1, 0, sizeof(p1)); 431 if (tnl_get_ioctl(name, &p1)) 432 continue; 433 if ((p->link && p1.link != p->link) || 434 (p->name[0] && strcmp(p1.name, p->name)) || 435 (p->iph.daddr && p1.iph.daddr != p->iph.daddr) || 436 (p->iph.saddr && p1.iph.saddr != p->iph.saddr) || 437 (p->i_key && p1.i_key != p->i_key)) 438 continue; 439 print_tunnel(&p1); 440 if (show_stats) 441 tnl_print_stats(ptr); 442 printf("\n"); 443 } 444 err = 0; 445 end: 446 fclose(fp); 447 return err; 448 } 449 450 static int do_show(int argc, char **argv) 451 { 452 struct ip_tunnel_parm p; 453 const char *basedev; 454 455 ll_init_map(&rth); 456 if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0) 457 return -1; 458 459 basedev = tnl_defname(&p); 460 if (!basedev) 461 return do_tunnels_list(&p); 462 463 if (tnl_get_ioctl(p.name[0] ? p.name : basedev, &p)) 464 return -1; 465 466 print_tunnel(&p); 467 printf("\n"); 468 return 0; 469 } 470 471 static int do_prl(int argc, char **argv) 472 { 473 struct ip_tunnel_prl p; 474 int count = 0; 475 int devname = 0; 476 int cmd = 0; 477 char medium[IFNAMSIZ]; 478 479 memset(&p, 0, sizeof(p)); 480 memset(&medium, 0, sizeof(medium)); 481 482 while (argc > 0) { 483 if (strcmp(*argv, "prl-default") == 0) { 484 NEXT_ARG(); 485 cmd = SIOCADDPRL; 486 p.addr = get_addr32(*argv); 487 p.flags |= PRL_DEFAULT; 488 count++; 489 } else if (strcmp(*argv, "prl-nodefault") == 0) { 490 NEXT_ARG(); 491 cmd = SIOCADDPRL; 492 p.addr = get_addr32(*argv); 493 count++; 494 } else if (strcmp(*argv, "prl-delete") == 0) { 495 NEXT_ARG(); 496 cmd = SIOCDELPRL; 497 p.addr = get_addr32(*argv); 498 count++; 499 } else if (strcmp(*argv, "dev") == 0) { 500 NEXT_ARG(); 501 strncpy(medium, *argv, IFNAMSIZ-1); 502 devname++; 503 } else { 504 fprintf(stderr, 505 "Invalid PRL parameter \"%s\"\n", *argv); 506 exit(-1); 507 } 508 if (count > 1) { 509 fprintf(stderr, 510 "One PRL entry at a time\n"); 511 exit(-1); 512 } 513 argc--; argv++; 514 } 515 if (devname == 0) { 516 fprintf(stderr, "Must specify device\n"); 517 exit(-1); 518 } 519 520 return tnl_prl_ioctl(cmd, medium, &p); 521 } 522 523 static int do_6rd(int argc, char **argv) 524 { 525 struct ip_tunnel_6rd ip6rd; 526 int devname = 0; 527 int cmd = 0; 528 char medium[IFNAMSIZ]; 529 inet_prefix prefix; 530 531 memset(&ip6rd, 0, sizeof(ip6rd)); 532 memset(&medium, 0, sizeof(medium)); 533 534 while (argc > 0) { 535 if (strcmp(*argv, "6rd-prefix") == 0) { 536 NEXT_ARG(); 537 if (get_prefix(&prefix, *argv, AF_INET6)) 538 invarg("invalid 6rd_prefix\n", *argv); 539 cmd = SIOCADD6RD; 540 memcpy(&ip6rd.prefix, prefix.data, 16); 541 ip6rd.prefixlen = prefix.bitlen; 542 } else if (strcmp(*argv, "6rd-relay_prefix") == 0) { 543 NEXT_ARG(); 544 if (get_prefix(&prefix, *argv, AF_INET)) 545 invarg("invalid 6rd-relay_prefix\n", *argv); 546 cmd = SIOCADD6RD; 547 memcpy(&ip6rd.relay_prefix, prefix.data, 4); 548 ip6rd.relay_prefixlen = prefix.bitlen; 549 } else if (strcmp(*argv, "6rd-reset") == 0) { 550 cmd = SIOCDEL6RD; 551 } else if (strcmp(*argv, "dev") == 0) { 552 NEXT_ARG(); 553 strncpy(medium, *argv, IFNAMSIZ-1); 554 devname++; 555 } else { 556 fprintf(stderr, 557 "Invalid 6RD parameter \"%s\"\n", *argv); 558 exit(-1); 559 } 560 argc--; argv++; 561 } 562 if (devname == 0) { 563 fprintf(stderr, "Must specify device\n"); 564 exit(-1); 565 } 566 567 return tnl_6rd_ioctl(cmd, medium, &ip6rd); 568 } 569 570 static int tunnel_mode_is_ipv6(char *tunnel_mode) 571 { 572 static const char * const ipv6_modes[] = { 573 "ipv6/ipv6", "ip6ip6", 574 "vti6", 575 "ip/ipv6", "ipv4/ipv6", "ipip6", "ip4ip6", 576 "ip6gre", "gre/ipv6", 577 "any/ipv6", "any" 578 }; 579 int i; 580 581 for (i = 0; i < ARRAY_SIZE(ipv6_modes); i++) { 582 if (strcmp(ipv6_modes[i], tunnel_mode) == 0) 583 return 1; 584 } 585 return 0; 586 } 587 588 int do_iptunnel(int argc, char **argv) 589 { 590 int i; 591 592 for (i = 0; i < argc - 1; i++) { 593 if (strcmp(argv[i], "mode") == 0) { 594 if (tunnel_mode_is_ipv6(argv[i + 1])) 595 preferred_family = AF_INET6; 596 break; 597 } 598 } 599 switch (preferred_family) { 600 case AF_UNSPEC: 601 preferred_family = AF_INET; 602 break; 603 case AF_INET: 604 break; 605 /* 606 * This is silly enough but we have no easy way to make it 607 * protocol-independent because of unarranged structure between 608 * IPv4 and IPv6. 609 */ 610 case AF_INET6: 611 return do_ip6tunnel(argc, argv); 612 default: 613 fprintf(stderr, "Unsupported protocol family: %d\n", preferred_family); 614 exit(-1); 615 } 616 617 if (argc > 0) { 618 if (matches(*argv, "add") == 0) 619 return do_add(SIOCADDTUNNEL, argc - 1, argv + 1); 620 if (matches(*argv, "change") == 0) 621 return do_add(SIOCCHGTUNNEL, argc - 1, argv + 1); 622 if (matches(*argv, "delete") == 0) 623 return do_del(argc - 1, argv + 1); 624 if (matches(*argv, "show") == 0 || 625 matches(*argv, "lst") == 0 || 626 matches(*argv, "list") == 0) 627 return do_show(argc - 1, argv + 1); 628 if (matches(*argv, "prl") == 0) 629 return do_prl(argc - 1, argv + 1); 630 if (matches(*argv, "6rd") == 0) 631 return do_6rd(argc - 1, argv + 1); 632 if (matches(*argv, "help") == 0) 633 usage(); 634 } else 635 return do_show(0, NULL); 636 637 fprintf(stderr, "Command \"%s\" is unknown, try \"ip tunnel help\"\n", *argv); 638 exit(-1); 639 } 640
