111820Sjulian/*- 211820Sjulian * Copyright (c) 2001 Charles Mott <cm@linktel.net> 311820Sjulian * Brian Somers <brian@Awfulhak.org> 411820Sjulian * All rights reserved. 511820Sjulian * 611820Sjulian * Redistribution and use in source and binary forms, with or without 711820Sjulian * modification, are permitted provided that the following conditions 811820Sjulian * are met: 911820Sjulian * 1. Redistributions of source code must retain the above copyright 1011820Sjulian * notice, this list of conditions and the following disclaimer. 1111820Sjulian * 2. Redistributions in binary form must reproduce the above copyright 1211820Sjulian * notice, this list of conditions and the following disclaimer in the 1311820Sjulian * documentation and/or other materials provided with the distribution. 1411820Sjulian * 1511820Sjulian * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1611820Sjulian * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1711820Sjulian * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1811820Sjulian * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 1911820Sjulian * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2011820Sjulian * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2111820Sjulian * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2211820Sjulian * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2311820Sjulian * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2411820Sjulian * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2511820Sjulian * SUCH DAMAGE. 2611820Sjulian * 2711820Sjulian * $FreeBSD$ 2811820Sjulian */ 2911820Sjulian 3011820Sjulian#include <sys/param.h> 3111820Sjulian#include <netinet/in.h> 3211820Sjulian#include <arpa/inet.h> 3311820Sjulian#include <netdb.h> 3411820Sjulian#include <netinet/in_systm.h> 3511820Sjulian#include <netinet/ip.h> 3611820Sjulian#include <sys/socket.h> 3711820Sjulian#include <sys/un.h> 3850479Speter 3911820Sjulian#include <stdarg.h> 4011820Sjulian#include <stdio.h> 4111820Sjulian#include <stdlib.h> 42122760Strhodes#include <string.h> 4311820Sjulian#include <termios.h> 4411820Sjulian 4511820Sjulian#ifdef LOCALNAT 4611820Sjulian#include "alias.h" 4711820Sjulian#else 4811820Sjulian#include <alias.h> 4911820Sjulian#endif 5011820Sjulian 5111820Sjulian#include "layer.h" 5211820Sjulian#include "proto.h" 5311820Sjulian#include "defs.h" 5411820Sjulian#include "command.h" 5511820Sjulian#include "log.h" 5611820Sjulian#include "nat_cmd.h" 5711820Sjulian#include "descriptor.h" 5811820Sjulian#include "prompt.h" 5911820Sjulian#include "timer.h" 6011820Sjulian#include "fsm.h" 6111820Sjulian#include "slcompress.h" 6211820Sjulian#include "throughput.h" 6311820Sjulian#include "iplist.h" 6411820Sjulian#include "mbuf.h" 6511820Sjulian#include "lqr.h" 6627244Sjhay#include "hdlc.h" 6711820Sjulian#include "ncpaddr.h" 6811820Sjulian#include "ip.h" 6911820Sjulian#include "ipcp.h" 7011820Sjulian#include "ipv6cp.h" 7111820Sjulian#include "lcp.h" 7211820Sjulian#include "ccp.h" 7311820Sjulian#include "link.h" 7411820Sjulian#include "mp.h" 7511820Sjulian#include "filter.h" 7627244Sjhay#ifndef NORADIUS 7711820Sjulian#include "radius.h" 7811820Sjulian#endif 7911820Sjulian#include "ncp.h" 8011820Sjulian#include "bundle.h" 8111820Sjulian 8211820Sjulian 8311820Sjulian#define NAT_EXTRABUF (13) 8411820Sjulian 8511820Sjulianstatic int StrToAddr(const char *, struct in_addr *); 8611820Sjulianstatic int StrToPortRange(const char *, u_short *, u_short *, const char *); 8711820Sjulianstatic int StrToAddrAndPort(const char *, struct in_addr *, u_short *, 8811820Sjulian u_short *, const char *); 8911820Sjulian 9011820Sjulianextern struct libalias *la; 9111820Sjulian 9211820Sjulianstatic void 9311820Sjulianlowhigh(u_short *a, u_short *b) 9411820Sjulian{ 9511820Sjulian if (a > b) { 9611820Sjulian u_short c; 9711820Sjulian 9811820Sjulian c = *b; 9911820Sjulian *b = *a; 10011820Sjulian *a = c; 10111820Sjulian } 10211820Sjulian} 10311820Sjulian 10411820Sjulianint 10511820Sjuliannat_RedirectPort(struct cmdargs const *arg) 10611820Sjulian{ 10711820Sjulian if (!arg->bundle->NatEnabled) { 10811820Sjulian prompt_Printf(arg->prompt, "Alias not enabled\n"); 10911820Sjulian return 1; 11011820Sjulian } else if (arg->argc == arg->argn + 3 || arg->argc == arg->argn + 4) { 11111820Sjulian char proto_constant; 11211820Sjulian const char *proto; 11327244Sjhay struct in_addr localaddr; 11411820Sjulian u_short hlocalport, llocalport; 11527244Sjhay struct in_addr aliasaddr; 11627244Sjhay u_short haliasport, laliasport; 11711820Sjulian struct in_addr remoteaddr; 11811820Sjulian u_short hremoteport, lremoteport; 11911820Sjulian struct alias_link *link; 12011820Sjulian int error; 12111820Sjulian 12211820Sjulian proto = arg->argv[arg->argn]; 12311820Sjulian if (strcmp(proto, "tcp") == 0) { 12411820Sjulian proto_constant = IPPROTO_TCP; 12511820Sjulian } else if (strcmp(proto, "udp") == 0) { 12611820Sjulian proto_constant = IPPROTO_UDP; 12711820Sjulian } else { 12827244Sjhay prompt_Printf(arg->prompt, "port redirect: protocol must be" 12927244Sjhay " tcp or udp\n"); 13011820Sjulian return -1; 13111820Sjulian } 13211820Sjulian 13311820Sjulian error = StrToAddrAndPort(arg->argv[arg->argn+1], &localaddr, &llocalport, 13411820Sjulian &hlocalport, proto); 13511820Sjulian if (error) { 13611820Sjulian prompt_Printf(arg->prompt, "nat port: error reading localaddr:port\n"); 13727244Sjhay return -1; 13811820Sjulian } 13911820Sjulian 14011820Sjulian error = StrToPortRange(arg->argv[arg->argn+2], &laliasport, &haliasport, 14111820Sjulian proto); 14227244Sjhay if (error) { 14311820Sjulian prompt_Printf(arg->prompt, "nat port: error reading alias port\n"); 14411820Sjulian return -1; 14511820Sjulian } 14611820Sjulian aliasaddr.s_addr = INADDR_ANY; 14711820Sjulian 14811820Sjulian if (arg->argc == arg->argn + 4) { 14911820Sjulian error = StrToAddrAndPort(arg->argv[arg->argn+3], &remoteaddr, 15011820Sjulian &lremoteport, &hremoteport, proto); 15111820Sjulian if (error) { 15211820Sjulian prompt_Printf(arg->prompt, "nat port: error reading " 15311820Sjulian "remoteaddr:port\n"); 15411820Sjulian return -1; 15511820Sjulian } 15611820Sjulian } else { 15711820Sjulian remoteaddr.s_addr = INADDR_ANY; 15811820Sjulian lremoteport = hremoteport = 0; 15911820Sjulian } 16011820Sjulian 16111820Sjulian lowhigh(&llocalport, &hlocalport); 16211820Sjulian lowhigh(&laliasport, &haliasport); 16311820Sjulian lowhigh(&lremoteport, &hremoteport); 16411820Sjulian 16511820Sjulian if (haliasport - laliasport != hlocalport - llocalport) { 16611820Sjulian prompt_Printf(arg->prompt, "nat port: local & alias port ranges " 16711820Sjulian "are not equal\n"); 16811820Sjulian return -1; 16911820Sjulian } 17011820Sjulian 17111820Sjulian if (hremoteport && hremoteport - lremoteport != hlocalport - llocalport) { 17227244Sjhay prompt_Printf(arg->prompt, "nat port: local & remote port ranges " 17327244Sjhay "are not equal\n"); 17427244Sjhay return -1; 17527244Sjhay } 17611820Sjulian 17711820Sjulian do { 17811820Sjulian link = LibAliasRedirectPort(la, localaddr, htons(llocalport), 17911820Sjulian remoteaddr, htons(lremoteport), 18011820Sjulian aliasaddr, htons(laliasport), 18111820Sjulian proto_constant); 18211820Sjulian 18311820Sjulian if (link == NULL) { 18411820Sjulian prompt_Printf(arg->prompt, "nat port: %d: error %d\n", laliasport, 18527244Sjhay error); 18627244Sjhay return 1; 18727244Sjhay } 18827244Sjhay llocalport++; 18927244Sjhay if (hremoteport) 19027244Sjhay lremoteport++; 19127244Sjhay } while (laliasport++ < haliasport); 19227244Sjhay 19327244Sjhay return 0; 19427244Sjhay } 19527244Sjhay 19627244Sjhay return -1; 19727244Sjhay} 19827244Sjhay 19927244Sjhay 20011820Sjulianint 20111820Sjuliannat_RedirectAddr(struct cmdargs const *arg) 20211820Sjulian{ 20327244Sjhay if (!arg->bundle->NatEnabled) { 20411820Sjulian prompt_Printf(arg->prompt, "nat not enabled\n"); 20511820Sjulian return 1; 20611820Sjulian } else if (arg->argc == arg->argn+2) { 20711820Sjulian int error; 20811820Sjulian struct in_addr localaddr, aliasaddr; 20911820Sjulian struct alias_link *link; 21011820Sjulian 21111820Sjulian error = StrToAddr(arg->argv[arg->argn], &localaddr); 21211820Sjulian if (error) { 21311820Sjulian prompt_Printf(arg->prompt, "address redirect: invalid local address\n"); 21411820Sjulian return 1; 21511820Sjulian } 21611820Sjulian error = StrToAddr(arg->argv[arg->argn+1], &aliasaddr); 21711820Sjulian if (error) { 21811820Sjulian prompt_Printf(arg->prompt, "address redirect: invalid alias address\n"); 21911820Sjulian prompt_Printf(arg->prompt, "usage: nat %s %s\n", arg->cmd->name, 22027244Sjhay arg->cmd->syntax); 22111820Sjulian return 1; 22211820Sjulian } 22311820Sjulian link = LibAliasRedirectAddr(la, localaddr, aliasaddr); 22411820Sjulian if (link == NULL) { 22527244Sjhay prompt_Printf(arg->prompt, "address redirect: packet aliasing" 22611820Sjulian " engine error\n"); 22711820Sjulian prompt_Printf(arg->prompt, "usage: nat %s %s\n", arg->cmd->name, 22811820Sjulian arg->cmd->syntax); 22911820Sjulian } 23011820Sjulian } else 23111820Sjulian return -1; 23211820Sjulian 23311820Sjulian return 0; 23411820Sjulian} 23511820Sjulian 23627244Sjhay 23711820Sjulianint 23811820Sjuliannat_RedirectProto(struct cmdargs const *arg) 23911820Sjulian{ 240 if (!arg->bundle->NatEnabled) { 241 prompt_Printf(arg->prompt, "nat not enabled\n"); 242 return 1; 243 } else if (arg->argc >= arg->argn + 2 && arg->argc <= arg->argn + 4) { 244 struct in_addr localIP, publicIP, remoteIP; 245 struct alias_link *link; 246 struct protoent *pe; 247 int error; 248 unsigned len; 249 250 len = strlen(arg->argv[arg->argn]); 251 if (len == 0) { 252 prompt_Printf(arg->prompt, "proto redirect: invalid protocol\n"); 253 return 1; 254 } 255 if (strspn(arg->argv[arg->argn], "01234567") == len) 256 pe = getprotobynumber(atoi(arg->argv[arg->argn])); 257 else 258 pe = getprotobyname(arg->argv[arg->argn]); 259 if (pe == NULL) { 260 prompt_Printf(arg->prompt, "proto redirect: invalid protocol\n"); 261 return 1; 262 } 263 264 error = StrToAddr(arg->argv[arg->argn + 1], &localIP); 265 if (error) { 266 prompt_Printf(arg->prompt, "proto redirect: invalid src address\n"); 267 return 1; 268 } 269 270 if (arg->argc >= arg->argn + 3) { 271 error = StrToAddr(arg->argv[arg->argn + 2], &publicIP); 272 if (error) { 273 prompt_Printf(arg->prompt, "proto redirect: invalid alias address\n"); 274 prompt_Printf(arg->prompt, "usage: nat %s %s\n", arg->cmd->name, 275 arg->cmd->syntax); 276 return 1; 277 } 278 } else 279 publicIP.s_addr = INADDR_ANY; 280 281 if (arg->argc == arg->argn + 4) { 282 error = StrToAddr(arg->argv[arg->argn + 2], &remoteIP); 283 if (error) { 284 prompt_Printf(arg->prompt, "proto redirect: invalid dst address\n"); 285 prompt_Printf(arg->prompt, "usage: nat %s %s\n", arg->cmd->name, 286 arg->cmd->syntax); 287 return 1; 288 } 289 } else 290 remoteIP.s_addr = INADDR_ANY; 291 292 link = LibAliasRedirectProto(la, localIP, remoteIP, publicIP, pe->p_proto); 293 if (link == NULL) { 294 prompt_Printf(arg->prompt, "proto redirect: packet aliasing" 295 " engine error\n"); 296 prompt_Printf(arg->prompt, "usage: nat %s %s\n", arg->cmd->name, 297 arg->cmd->syntax); 298 } 299 } else 300 return -1; 301 302 return 0; 303} 304 305 306static int 307StrToAddr(const char *str, struct in_addr *addr) 308{ 309 struct hostent *hp; 310 311 if (inet_aton(str, addr)) 312 return 0; 313 314 hp = gethostbyname(str); 315 if (!hp) { 316 log_Printf(LogWARN, "StrToAddr: Unknown host %s.\n", str); 317 return -1; 318 } 319 *addr = *((struct in_addr *) hp->h_addr); 320 return 0; 321} 322 323 324static int 325StrToPort(const char *str, u_short *port, const char *proto) 326{ 327 struct servent *sp; 328 char *end; 329 330 *port = strtol(str, &end, 10); 331 if (*end != '\0') { 332 sp = getservbyname(str, proto); 333 if (sp == NULL) { 334 log_Printf(LogWARN, "StrToAddr: Unknown port or service %s/%s.\n", 335 str, proto); 336 return -1; 337 } 338 *port = ntohs(sp->s_port); 339 } 340 341 return 0; 342} 343 344static int 345StrToPortRange(const char *str, u_short *low, u_short *high, const char *proto) 346{ 347 char *minus; 348 int res; 349 350 minus = strchr(str, '-'); 351 if (minus) 352 *minus = '\0'; /* Cheat the const-ness ! */ 353 354 res = StrToPort(str, low, proto); 355 356 if (minus) 357 *minus = '-'; /* Cheat the const-ness ! */ 358 359 if (res == 0) { 360 if (minus) 361 res = StrToPort(minus + 1, high, proto); 362 else 363 *high = *low; 364 } 365 366 return res; 367} 368 369static int 370StrToAddrAndPort(const char *str, struct in_addr *addr, u_short *low, 371 u_short *high, const char *proto) 372{ 373 char *colon; 374 int res; 375 376 colon = strchr(str, ':'); 377 if (!colon) { 378 log_Printf(LogWARN, "StrToAddrAndPort: %s is missing port number.\n", str); 379 return -1; 380 } 381 382 *colon = '\0'; /* Cheat the const-ness ! */ 383 res = StrToAddr(str, addr); 384 *colon = ':'; /* Cheat the const-ness ! */ 385 if (res != 0) 386 return -1; 387 388 return StrToPortRange(colon + 1, low, high, proto); 389} 390 391int 392nat_ProxyRule(struct cmdargs const *arg) 393{ 394 char cmd[LINE_LEN]; 395 int f, pos; 396 size_t len; 397 398 if (arg->argn >= arg->argc) 399 return -1; 400 401 for (f = arg->argn, pos = 0; f < arg->argc; f++) { 402 len = strlen(arg->argv[f]); 403 if (sizeof cmd - pos < len + (len ? 1 : 0)) 404 break; 405 if (len) 406 cmd[pos++] = ' '; 407 strcpy(cmd + pos, arg->argv[f]); 408 pos += len; 409 } 410 411 return LibAliasProxyRule(la, cmd); 412} 413 414int 415nat_SetTarget(struct cmdargs const *arg) 416{ 417 struct in_addr addr; 418 419 if (arg->argc == arg->argn) { 420 addr.s_addr = INADDR_ANY; 421 LibAliasSetTarget(la, addr); 422 return 0; 423 } 424 425 if (arg->argc != arg->argn + 1) 426 return -1; 427 428 if (!strcasecmp(arg->argv[arg->argn], "MYADDR")) { 429 addr.s_addr = INADDR_ANY; 430 LibAliasSetTarget(la, addr); 431 return 0; 432 } 433 434 addr = GetIpAddr(arg->argv[arg->argn]); 435 if (addr.s_addr == INADDR_NONE) { 436 log_Printf(LogWARN, "%s: invalid address\n", arg->argv[arg->argn]); 437 return 1; 438 } 439 440 LibAliasSetTarget(la, addr); 441 return 0; 442} 443 444#ifndef NO_FW_PUNCH 445int 446nat_PunchFW(struct cmdargs const *arg) 447{ 448 char *end; 449 long base, count; 450 451 if (arg->argc == arg->argn) { 452 LibAliasSetMode(la, 0, PKT_ALIAS_PUNCH_FW); 453 return 0; 454 } 455 456 if (arg->argc != arg->argn + 2) 457 return -1; 458 459 base = strtol(arg->argv[arg->argn], &end, 10); 460 if (*end != '\0' || base < 0) 461 return -1; 462 463 count = strtol(arg->argv[arg->argn + 1], &end, 10); 464 if (*end != '\0' || count < 0) 465 return -1; 466 467 LibAliasSetFWBase(la, base, count); 468 LibAliasSetMode(la, PKT_ALIAS_PUNCH_FW, PKT_ALIAS_PUNCH_FW); 469 470 return 0; 471} 472#endif 473 474int 475nat_SkinnyPort(struct cmdargs const *arg) 476{ 477 char *end; 478 long port; 479 480 if (arg->argc == arg->argn) { 481 LibAliasSetSkinnyPort(la, 0); 482 return 0; 483 } 484 485 if (arg->argc != arg->argn + 1) 486 return -1; 487 488 port = strtol(arg->argv[arg->argn], &end, 10); 489 if (*end != '\0' || port < 0) 490 return -1; 491 492 LibAliasSetSkinnyPort(la, port); 493 494 return 0; 495} 496 497static struct mbuf * 498nat_LayerPush(struct bundle *bundle, struct link *l __unused, struct mbuf *bp, 499 int pri __unused, u_short *proto) 500{ 501 if (!bundle->NatEnabled || *proto != PROTO_IP) 502 return bp; 503 504 log_Printf(LogDEBUG, "nat_LayerPush: PROTO_IP -> PROTO_IP\n"); 505 m_settype(bp, MB_NATOUT); 506 /* Ensure there's a bit of extra buffer for the NAT code... */ 507 bp = m_pullup(m_append(bp, NULL, NAT_EXTRABUF)); 508 LibAliasOut(la, MBUF_CTOP(bp), bp->m_len); 509 bp->m_len = ntohs(((struct ip *)MBUF_CTOP(bp))->ip_len); 510 511 return bp; 512} 513 514static struct mbuf * 515nat_LayerPull(struct bundle *bundle, struct link *l __unused, struct mbuf *bp, 516 u_short *proto) 517{ 518 static int gfrags; 519 int ret, len, nfrags; 520 struct mbuf **last; 521 char *fptr; 522 523 if (!bundle->NatEnabled || *proto != PROTO_IP) 524 return bp; 525 526 log_Printf(LogDEBUG, "nat_LayerPull: PROTO_IP -> PROTO_IP\n"); 527 m_settype(bp, MB_NATIN); 528 /* Ensure there's a bit of extra buffer for the NAT code... */ 529 bp = m_pullup(m_append(bp, NULL, NAT_EXTRABUF)); 530 ret = LibAliasIn(la, MBUF_CTOP(bp), bp->m_len); 531 532 bp->m_len = ntohs(((struct ip *)MBUF_CTOP(bp))->ip_len); 533 if (bp->m_len > MAX_MRU) { 534 log_Printf(LogWARN, "nat_LayerPull: Problem with IP header length (%lu)\n", 535 (unsigned long)bp->m_len); 536 m_freem(bp); 537 return NULL; 538 } 539 540 switch (ret) { 541 case PKT_ALIAS_OK: 542 break; 543 544 case PKT_ALIAS_UNRESOLVED_FRAGMENT: 545 /* Save the data for later */ 546 if ((fptr = malloc(bp->m_len)) == NULL) { 547 log_Printf(LogWARN, "nat_LayerPull: Dropped unresolved fragment -" 548 " out of memory!\n"); 549 m_freem(bp); 550 bp = NULL; 551 } else { 552 bp = mbuf_Read(bp, fptr, bp->m_len); 553 LibAliasSaveFragment(la, fptr); 554 log_Printf(LogDEBUG, "Store another frag (%lu) - now %d\n", 555 (unsigned long)((struct ip *)fptr)->ip_id, ++gfrags); 556 } 557 break; 558 559 case PKT_ALIAS_FOUND_HEADER_FRAGMENT: 560 /* Fetch all the saved fragments and chain them on the end of `bp' */ 561 last = &bp->m_nextpkt; 562 nfrags = 0; 563 while ((fptr = LibAliasGetFragment(la, MBUF_CTOP(bp))) != NULL) { 564 nfrags++; 565 LibAliasFragmentIn(la, MBUF_CTOP(bp), fptr); 566 len = ntohs(((struct ip *)fptr)->ip_len); 567 *last = m_get(len, MB_NATIN); 568 memcpy(MBUF_CTOP(*last), fptr, len); 569 free(fptr); 570 last = &(*last)->m_nextpkt; 571 } 572 gfrags -= nfrags; 573 log_Printf(LogDEBUG, "Found a frag header (%lu) - plus %d more frags (no" 574 "w %d)\n", (unsigned long)((struct ip *)MBUF_CTOP(bp))->ip_id, 575 nfrags, gfrags); 576 break; 577 578 case PKT_ALIAS_IGNORED: 579 if (LibAliasSetMode(la, 0, 0) & PKT_ALIAS_DENY_INCOMING) { 580 log_Printf(LogTCPIP, "NAT engine denied data:\n"); 581 m_freem(bp); 582 bp = NULL; 583 } else if (log_IsKept(LogTCPIP)) { 584 log_Printf(LogTCPIP, "NAT engine ignored data:\n"); 585 PacketCheck(bundle, AF_INET, MBUF_CTOP(bp), bp->m_len, NULL, 586 NULL, NULL); 587 } 588 break; 589 590 default: 591 log_Printf(LogWARN, "nat_LayerPull: Dropped a packet (%d)....\n", ret); 592 m_freem(bp); 593 bp = NULL; 594 break; 595 } 596 597 return bp; 598} 599 600struct layer natlayer = 601 { LAYER_NAT, "nat", nat_LayerPush, nat_LayerPull }; 602