ip_fw_nat.c revision 196019
1/*- 2 * Copyright (c) 2008 Paolo Pisati 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/netinet/ipfw/ip_fw_nat.c 196019 2009-08-01 19:26:27Z rwatson $"); 29 30#include <sys/param.h> 31#include <sys/systm.h> 32#include <sys/condvar.h> 33#include <sys/eventhandler.h> 34#include <sys/malloc.h> 35#include <sys/mbuf.h> 36#include <sys/kernel.h> 37#include <sys/lock.h> 38#include <sys/jail.h> 39#include <sys/module.h> 40#include <sys/priv.h> 41#include <sys/proc.h> 42#include <sys/rwlock.h> 43#include <sys/socket.h> 44#include <sys/socketvar.h> 45#include <sys/sysctl.h> 46#include <sys/syslog.h> 47#include <sys/ucred.h> 48 49#include <netinet/libalias/alias.h> 50#include <netinet/libalias/alias_local.h> 51 52#define IPFW_INTERNAL /* Access to protected data structures in ip_fw.h. */ 53 54#include <net/if.h> 55#include <netinet/in.h> 56#include <netinet/ip.h> 57#include <netinet/ip_var.h> 58#include <netinet/ip_icmp.h> 59#include <netinet/ip_fw.h> 60#include <netinet/tcp.h> 61#include <netinet/tcp_timer.h> 62#include <netinet/tcp_var.h> 63#include <netinet/tcpip.h> 64#include <netinet/udp.h> 65#include <netinet/udp_var.h> 66 67#include <machine/in_cksum.h> /* XXX for in_cksum */ 68 69MALLOC_DECLARE(M_IPFW); 70 71static VNET_DEFINE(eventhandler_tag, ifaddr_event_tag); 72#define V_ifaddr_event_tag VNET(ifaddr_event_tag) 73 74extern ipfw_nat_t *ipfw_nat_ptr; 75extern ipfw_nat_cfg_t *ipfw_nat_cfg_ptr; 76extern ipfw_nat_cfg_t *ipfw_nat_del_ptr; 77extern ipfw_nat_cfg_t *ipfw_nat_get_cfg_ptr; 78extern ipfw_nat_cfg_t *ipfw_nat_get_log_ptr; 79 80static void 81ifaddr_change(void *arg __unused, struct ifnet *ifp) 82{ 83 struct cfg_nat *ptr; 84 struct ifaddr *ifa; 85 86 IPFW_WLOCK(&V_layer3_chain); 87 /* Check every nat entry... */ 88 LIST_FOREACH(ptr, &V_layer3_chain.nat, _next) { 89 /* ...using nic 'ifp->if_xname' as dynamic alias address. */ 90 if (strncmp(ptr->if_name, ifp->if_xname, IF_NAMESIZE) == 0) { 91 if_addr_rlock(ifp); 92 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 93 if (ifa->ifa_addr == NULL) 94 continue; 95 if (ifa->ifa_addr->sa_family != AF_INET) 96 continue; 97 ptr->ip = ((struct sockaddr_in *) 98 (ifa->ifa_addr))->sin_addr; 99 LibAliasSetAddress(ptr->lib, ptr->ip); 100 } 101 if_addr_runlock(ifp); 102 } 103 } 104 IPFW_WUNLOCK(&V_layer3_chain); 105} 106 107static void 108flush_nat_ptrs(const int i) 109{ 110 struct ip_fw *rule; 111 112 IPFW_WLOCK_ASSERT(&V_layer3_chain); 113 for (rule = V_layer3_chain.rules; rule; rule = rule->next) { 114 ipfw_insn_nat *cmd = (ipfw_insn_nat *)ACTION_PTR(rule); 115 if (cmd->o.opcode != O_NAT) 116 continue; 117 if (cmd->nat != NULL && cmd->nat->id == i) 118 cmd->nat = NULL; 119 } 120} 121 122#define HOOK_NAT(b, p) do { \ 123 IPFW_WLOCK_ASSERT(&V_layer3_chain); \ 124 LIST_INSERT_HEAD(b, p, _next); \ 125 } while (0) 126 127#define UNHOOK_NAT(p) do { \ 128 IPFW_WLOCK_ASSERT(&V_layer3_chain); \ 129 LIST_REMOVE(p, _next); \ 130 } while (0) 131 132#define HOOK_REDIR(b, p) do { \ 133 LIST_INSERT_HEAD(b, p, _next); \ 134 } while (0) 135 136#define HOOK_SPOOL(b, p) do { \ 137 LIST_INSERT_HEAD(b, p, _next); \ 138 } while (0) 139 140static void 141del_redir_spool_cfg(struct cfg_nat *n, struct redir_chain *head) 142{ 143 struct cfg_redir *r, *tmp_r; 144 struct cfg_spool *s, *tmp_s; 145 int i, num; 146 147 LIST_FOREACH_SAFE(r, head, _next, tmp_r) { 148 num = 1; /* Number of alias_link to delete. */ 149 switch (r->mode) { 150 case REDIR_PORT: 151 num = r->pport_cnt; 152 /* FALLTHROUGH */ 153 case REDIR_ADDR: 154 case REDIR_PROTO: 155 /* Delete all libalias redirect entry. */ 156 for (i = 0; i < num; i++) 157 LibAliasRedirectDelete(n->lib, r->alink[i]); 158 /* Del spool cfg if any. */ 159 LIST_FOREACH_SAFE(s, &r->spool_chain, _next, tmp_s) { 160 LIST_REMOVE(s, _next); 161 free(s, M_IPFW); 162 } 163 free(r->alink, M_IPFW); 164 LIST_REMOVE(r, _next); 165 free(r, M_IPFW); 166 break; 167 default: 168 printf("unknown redirect mode: %u\n", r->mode); 169 /* XXX - panic?!?!? */ 170 break; 171 } 172 } 173} 174 175static int 176add_redir_spool_cfg(char *buf, struct cfg_nat *ptr) 177{ 178 struct cfg_redir *r, *ser_r; 179 struct cfg_spool *s, *ser_s; 180 int cnt, off, i; 181 char *panic_err; 182 183 for (cnt = 0, off = 0; cnt < ptr->redir_cnt; cnt++) { 184 ser_r = (struct cfg_redir *)&buf[off]; 185 r = malloc(SOF_REDIR, M_IPFW, M_WAITOK | M_ZERO); 186 memcpy(r, ser_r, SOF_REDIR); 187 LIST_INIT(&r->spool_chain); 188 off += SOF_REDIR; 189 r->alink = malloc(sizeof(struct alias_link *) * r->pport_cnt, 190 M_IPFW, M_WAITOK | M_ZERO); 191 switch (r->mode) { 192 case REDIR_ADDR: 193 r->alink[0] = LibAliasRedirectAddr(ptr->lib, r->laddr, 194 r->paddr); 195 break; 196 case REDIR_PORT: 197 for (i = 0 ; i < r->pport_cnt; i++) { 198 /* If remotePort is all ports, set it to 0. */ 199 u_short remotePortCopy = r->rport + i; 200 if (r->rport_cnt == 1 && r->rport == 0) 201 remotePortCopy = 0; 202 r->alink[i] = LibAliasRedirectPort(ptr->lib, 203 r->laddr, htons(r->lport + i), r->raddr, 204 htons(remotePortCopy), r->paddr, 205 htons(r->pport + i), r->proto); 206 if (r->alink[i] == NULL) { 207 r->alink[0] = NULL; 208 break; 209 } 210 } 211 break; 212 case REDIR_PROTO: 213 r->alink[0] = LibAliasRedirectProto(ptr->lib ,r->laddr, 214 r->raddr, r->paddr, r->proto); 215 break; 216 default: 217 printf("unknown redirect mode: %u\n", r->mode); 218 break; 219 } 220 if (r->alink[0] == NULL) { 221 panic_err = "LibAliasRedirect* returned NULL"; 222 goto bad; 223 } else /* LSNAT handling. */ 224 for (i = 0; i < r->spool_cnt; i++) { 225 ser_s = (struct cfg_spool *)&buf[off]; 226 s = malloc(SOF_REDIR, M_IPFW, 227 M_WAITOK | M_ZERO); 228 memcpy(s, ser_s, SOF_SPOOL); 229 LibAliasAddServer(ptr->lib, r->alink[0], 230 s->addr, htons(s->port)); 231 off += SOF_SPOOL; 232 /* Hook spool entry. */ 233 HOOK_SPOOL(&r->spool_chain, s); 234 } 235 /* And finally hook this redir entry. */ 236 HOOK_REDIR(&ptr->redir_chain, r); 237 } 238 return (1); 239bad: 240 /* something really bad happened: panic! */ 241 panic("%s\n", panic_err); 242} 243 244static int 245ipfw_nat(struct ip_fw_args *args, struct cfg_nat *t, struct mbuf *m) 246{ 247 struct mbuf *mcl; 248 struct ip *ip; 249 /* XXX - libalias duct tape */ 250 int ldt, retval; 251 char *c; 252 253 ldt = 0; 254 retval = 0; 255 if ((mcl = m_megapullup(m, m->m_pkthdr.len)) == 256 NULL) 257 goto badnat; 258 ip = mtod(mcl, struct ip *); 259 if (args->eh == NULL) { 260 ip->ip_len = htons(ip->ip_len); 261 ip->ip_off = htons(ip->ip_off); 262 } 263 264 /* 265 * XXX - Libalias checksum offload 'duct tape': 266 * 267 * locally generated packets have only 268 * pseudo-header checksum calculated 269 * and libalias will screw it[1], so 270 * mark them for later fix. Moreover 271 * there are cases when libalias 272 * modify tcp packet data[2], mark it 273 * for later fix too. 274 * 275 * [1] libalias was never meant to run 276 * in kernel, so it doesn't have any 277 * knowledge about checksum 278 * offloading, and it expects a packet 279 * with a full internet 280 * checksum. Unfortunately, packets 281 * generated locally will have just the 282 * pseudo header calculated, and when 283 * libalias tries to adjust the 284 * checksum it will actually screw it. 285 * 286 * [2] when libalias modify tcp's data 287 * content, full TCP checksum has to 288 * be recomputed: the problem is that 289 * libalias doesn't have any idea 290 * about checksum offloading To 291 * workaround this, we do not do 292 * checksumming in LibAlias, but only 293 * mark the packets in th_x2 field. If 294 * we receive a marked packet, we 295 * calculate correct checksum for it 296 * aware of offloading. Why such a 297 * terrible hack instead of 298 * recalculating checksum for each 299 * packet? Because the previous 300 * checksum was not checked! 301 * Recalculating checksums for EVERY 302 * packet will hide ALL transmission 303 * errors. Yes, marked packets still 304 * suffer from this problem. But, 305 * sigh, natd(8) has this problem, 306 * too. 307 * 308 * TODO: -make libalias mbuf aware (so 309 * it can handle delayed checksum and tso) 310 */ 311 312 if (mcl->m_pkthdr.rcvif == NULL && 313 mcl->m_pkthdr.csum_flags & 314 CSUM_DELAY_DATA) 315 ldt = 1; 316 317 c = mtod(mcl, char *); 318 if (args->oif == NULL) 319 retval = LibAliasIn(t->lib, c, 320 mcl->m_len + M_TRAILINGSPACE(mcl)); 321 else 322 retval = LibAliasOut(t->lib, c, 323 mcl->m_len + M_TRAILINGSPACE(mcl)); 324 if (retval == PKT_ALIAS_RESPOND) { 325 m->m_flags |= M_SKIP_FIREWALL; 326 retval = PKT_ALIAS_OK; 327 } 328 if (retval != PKT_ALIAS_OK && 329 retval != PKT_ALIAS_FOUND_HEADER_FRAGMENT) { 330 /* XXX - should i add some logging? */ 331 m_free(mcl); 332 badnat: 333 args->m = NULL; 334 return (IP_FW_DENY); 335 } 336 mcl->m_pkthdr.len = mcl->m_len = 337 ntohs(ip->ip_len); 338 339 /* 340 * XXX - libalias checksum offload 341 * 'duct tape' (see above) 342 */ 343 344 if ((ip->ip_off & htons(IP_OFFMASK)) == 0 && 345 ip->ip_p == IPPROTO_TCP) { 346 struct tcphdr *th; 347 348 th = (struct tcphdr *)(ip + 1); 349 if (th->th_x2) 350 ldt = 1; 351 } 352 353 if (ldt) { 354 struct tcphdr *th; 355 struct udphdr *uh; 356 u_short cksum; 357 358 ip->ip_len = ntohs(ip->ip_len); 359 cksum = in_pseudo( 360 ip->ip_src.s_addr, 361 ip->ip_dst.s_addr, 362 htons(ip->ip_p + ip->ip_len - (ip->ip_hl << 2)) 363 ); 364 365 switch (ip->ip_p) { 366 case IPPROTO_TCP: 367 th = (struct tcphdr *)(ip + 1); 368 /* 369 * Maybe it was set in 370 * libalias... 371 */ 372 th->th_x2 = 0; 373 th->th_sum = cksum; 374 mcl->m_pkthdr.csum_data = 375 offsetof(struct tcphdr, th_sum); 376 break; 377 case IPPROTO_UDP: 378 uh = (struct udphdr *)(ip + 1); 379 uh->uh_sum = cksum; 380 mcl->m_pkthdr.csum_data = 381 offsetof(struct udphdr, uh_sum); 382 break; 383 } 384 /* 385 * No hw checksum offloading: do it 386 * by ourself. 387 */ 388 if ((mcl->m_pkthdr.csum_flags & 389 CSUM_DELAY_DATA) == 0) { 390 in_delayed_cksum(mcl); 391 mcl->m_pkthdr.csum_flags &= 392 ~CSUM_DELAY_DATA; 393 } 394 ip->ip_len = htons(ip->ip_len); 395 } 396 397 if (args->eh == NULL) { 398 ip->ip_len = ntohs(ip->ip_len); 399 ip->ip_off = ntohs(ip->ip_off); 400 } 401 402 args->m = mcl; 403 return (IP_FW_NAT); 404} 405 406static int 407ipfw_nat_cfg(struct sockopt *sopt) 408{ 409 struct cfg_nat *ptr, *ser_n; 410 char *buf; 411 412 buf = malloc(NAT_BUF_LEN, M_IPFW, M_WAITOK | M_ZERO); 413 sooptcopyin(sopt, buf, NAT_BUF_LEN, 414 sizeof(struct cfg_nat)); 415 ser_n = (struct cfg_nat *)buf; 416 417 /* 418 * Find/create nat rule. 419 */ 420 IPFW_WLOCK(&V_layer3_chain); 421 LOOKUP_NAT(V_layer3_chain, ser_n->id, ptr); 422 if (ptr == NULL) { 423 /* New rule: allocate and init new instance. */ 424 ptr = malloc(sizeof(struct cfg_nat), 425 M_IPFW, M_NOWAIT | M_ZERO); 426 if (ptr == NULL) { 427 IPFW_WUNLOCK(&V_layer3_chain); 428 free(buf, M_IPFW); 429 return (ENOSPC); 430 } 431 ptr->lib = LibAliasInit(NULL); 432 if (ptr->lib == NULL) { 433 IPFW_WUNLOCK(&V_layer3_chain); 434 free(ptr, M_IPFW); 435 free(buf, M_IPFW); 436 return (EINVAL); 437 } 438 LIST_INIT(&ptr->redir_chain); 439 } else { 440 /* Entry already present: temporarly unhook it. */ 441 UNHOOK_NAT(ptr); 442 flush_nat_ptrs(ser_n->id); 443 } 444 IPFW_WUNLOCK(&V_layer3_chain); 445 446 /* 447 * Basic nat configuration. 448 */ 449 ptr->id = ser_n->id; 450 /* 451 * XXX - what if this rule doesn't nat any ip and just 452 * redirect? 453 * do we set aliasaddress to 0.0.0.0? 454 */ 455 ptr->ip = ser_n->ip; 456 ptr->redir_cnt = ser_n->redir_cnt; 457 ptr->mode = ser_n->mode; 458 LibAliasSetMode(ptr->lib, ser_n->mode, ser_n->mode); 459 LibAliasSetAddress(ptr->lib, ptr->ip); 460 memcpy(ptr->if_name, ser_n->if_name, IF_NAMESIZE); 461 462 /* 463 * Redir and LSNAT configuration. 464 */ 465 /* Delete old cfgs. */ 466 del_redir_spool_cfg(ptr, &ptr->redir_chain); 467 /* Add new entries. */ 468 add_redir_spool_cfg(&buf[(sizeof(struct cfg_nat))], ptr); 469 free(buf, M_IPFW); 470 IPFW_WLOCK(&V_layer3_chain); 471 HOOK_NAT(&V_layer3_chain.nat, ptr); 472 IPFW_WUNLOCK(&V_layer3_chain); 473 return (0); 474} 475 476static int 477ipfw_nat_del(struct sockopt *sopt) 478{ 479 struct cfg_nat *ptr; 480 int i; 481 482 sooptcopyin(sopt, &i, sizeof i, sizeof i); 483 IPFW_WLOCK(&V_layer3_chain); 484 LOOKUP_NAT(V_layer3_chain, i, ptr); 485 if (ptr == NULL) { 486 IPFW_WUNLOCK(&V_layer3_chain); 487 return (EINVAL); 488 } 489 UNHOOK_NAT(ptr); 490 flush_nat_ptrs(i); 491 IPFW_WUNLOCK(&V_layer3_chain); 492 del_redir_spool_cfg(ptr, &ptr->redir_chain); 493 LibAliasUninit(ptr->lib); 494 free(ptr, M_IPFW); 495 return (0); 496} 497 498static int 499ipfw_nat_get_cfg(struct sockopt *sopt) 500{ 501 uint8_t *data; 502 struct cfg_nat *n; 503 struct cfg_redir *r; 504 struct cfg_spool *s; 505 int nat_cnt, off; 506 507 nat_cnt = 0; 508 off = sizeof(nat_cnt); 509 510 data = malloc(NAT_BUF_LEN, M_IPFW, M_WAITOK | M_ZERO); 511 IPFW_RLOCK(&V_layer3_chain); 512 /* Serialize all the data. */ 513 LIST_FOREACH(n, &V_layer3_chain.nat, _next) { 514 nat_cnt++; 515 if (off + SOF_NAT < NAT_BUF_LEN) { 516 bcopy(n, &data[off], SOF_NAT); 517 off += SOF_NAT; 518 LIST_FOREACH(r, &n->redir_chain, _next) { 519 if (off + SOF_REDIR < NAT_BUF_LEN) { 520 bcopy(r, &data[off], 521 SOF_REDIR); 522 off += SOF_REDIR; 523 LIST_FOREACH(s, &r->spool_chain, 524 _next) { 525 if (off + SOF_SPOOL < 526 NAT_BUF_LEN) { 527 bcopy(s, &data[off], 528 SOF_SPOOL); 529 off += SOF_SPOOL; 530 } else 531 goto nospace; 532 } 533 } else 534 goto nospace; 535 } 536 } else 537 goto nospace; 538 } 539 bcopy(&nat_cnt, data, sizeof(nat_cnt)); 540 IPFW_RUNLOCK(&V_layer3_chain); 541 sooptcopyout(sopt, data, NAT_BUF_LEN); 542 free(data, M_IPFW); 543 return (0); 544nospace: 545 IPFW_RUNLOCK(&V_layer3_chain); 546 printf("serialized data buffer not big enough:" 547 "please increase NAT_BUF_LEN\n"); 548 free(data, M_IPFW); 549 return (ENOSPC); 550} 551 552static int 553ipfw_nat_get_log(struct sockopt *sopt) 554{ 555 uint8_t *data; 556 struct cfg_nat *ptr; 557 int i, size, cnt, sof; 558 559 data = NULL; 560 sof = LIBALIAS_BUF_SIZE; 561 cnt = 0; 562 563 IPFW_RLOCK(&V_layer3_chain); 564 size = i = 0; 565 LIST_FOREACH(ptr, &V_layer3_chain.nat, _next) { 566 if (ptr->lib->logDesc == NULL) 567 continue; 568 cnt++; 569 size = cnt * (sof + sizeof(int)); 570 data = realloc(data, size, M_IPFW, M_NOWAIT | M_ZERO); 571 if (data == NULL) { 572 IPFW_RUNLOCK(&V_layer3_chain); 573 return (ENOSPC); 574 } 575 bcopy(&ptr->id, &data[i], sizeof(int)); 576 i += sizeof(int); 577 bcopy(ptr->lib->logDesc, &data[i], sof); 578 i += sof; 579 } 580 IPFW_RUNLOCK(&V_layer3_chain); 581 sooptcopyout(sopt, data, size); 582 free(data, M_IPFW); 583 return(0); 584} 585 586static void 587ipfw_nat_init(void) 588{ 589 590 IPFW_WLOCK(&V_layer3_chain); 591 /* init ipfw hooks */ 592 ipfw_nat_ptr = ipfw_nat; 593 ipfw_nat_cfg_ptr = ipfw_nat_cfg; 594 ipfw_nat_del_ptr = ipfw_nat_del; 595 ipfw_nat_get_cfg_ptr = ipfw_nat_get_cfg; 596 ipfw_nat_get_log_ptr = ipfw_nat_get_log; 597 IPFW_WUNLOCK(&V_layer3_chain); 598 V_ifaddr_event_tag = EVENTHANDLER_REGISTER(ifaddr_event, ifaddr_change, 599 NULL, EVENTHANDLER_PRI_ANY); 600} 601 602static void 603ipfw_nat_destroy(void) 604{ 605 struct ip_fw *rule; 606 struct cfg_nat *ptr, *ptr_temp; 607 608 IPFW_WLOCK(&V_layer3_chain); 609 LIST_FOREACH_SAFE(ptr, &V_layer3_chain.nat, _next, ptr_temp) { 610 LIST_REMOVE(ptr, _next); 611 del_redir_spool_cfg(ptr, &ptr->redir_chain); 612 LibAliasUninit(ptr->lib); 613 free(ptr, M_IPFW); 614 } 615 EVENTHANDLER_DEREGISTER(ifaddr_event, V_ifaddr_event_tag); 616 /* flush all nat ptrs */ 617 for (rule = V_layer3_chain.rules; rule; rule = rule->next) { 618 ipfw_insn_nat *cmd = (ipfw_insn_nat *)ACTION_PTR(rule); 619 if (cmd->o.opcode == O_NAT) 620 cmd->nat = NULL; 621 } 622 /* deregister ipfw_nat */ 623 ipfw_nat_ptr = NULL; 624 IPFW_WUNLOCK(&V_layer3_chain); 625} 626 627static int 628ipfw_nat_modevent(module_t mod, int type, void *unused) 629{ 630 int err = 0; 631 632 switch (type) { 633 case MOD_LOAD: 634 ipfw_nat_init(); 635 break; 636 637 case MOD_UNLOAD: 638 ipfw_nat_destroy(); 639 break; 640 641 default: 642 return EOPNOTSUPP; 643 break; 644 } 645 return err; 646} 647 648static moduledata_t ipfw_nat_mod = { 649 "ipfw_nat", 650 ipfw_nat_modevent, 651 0 652}; 653 654DECLARE_MODULE(ipfw_nat, ipfw_nat_mod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); 655MODULE_DEPEND(ipfw_nat, libalias, 1, 1, 1); 656MODULE_DEPEND(ipfw_nat, ipfw, 2, 2, 2); 657MODULE_VERSION(ipfw_nat, 1); 658