1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2004 Andre Oppermann, Internet Business Solutions AG 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "opt_ipfw.h" 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 #ifndef INET 36 #error IPFIREWALL requires INET. 37 #endif /* INET */ 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/module.h> 44 #include <sys/kernel.h> 45 #include <sys/lock.h> 46 #include <sys/rwlock.h> 47 #include <sys/socket.h> 48 #include <sys/sysctl.h> 49 50 #include <net/if.h> 51 #include <net/if_var.h> 52 #include <net/route.h> 53 #include <net/ethernet.h> 54 #include <net/pfil.h> 55 #include <net/vnet.h> 56 57 #include <netinet/in.h> 58 #include <netinet/in_systm.h> 59 #include <netinet/ip.h> 60 #include <netinet/ip_var.h> 61 #include <netinet/ip_fw.h> 62 #ifdef INET6 63 #include <netinet/ip6.h> 64 #include <netinet6/ip6_var.h> 65 #include <netinet6/scope6_var.h> 66 #endif 67 68 #include <netgraph/ng_ipfw.h> 69 70 #include <netpfil/ipfw/ip_fw_private.h> 71 72 #include <machine/in_cksum.h> 73 74 VNET_DEFINE_STATIC(int, fw_enable) = 1; 75 #define V_fw_enable VNET(fw_enable) 76 77 #ifdef INET6 78 VNET_DEFINE_STATIC(int, fw6_enable) = 1; 79 #define V_fw6_enable VNET(fw6_enable) 80 #endif 81 82 VNET_DEFINE_STATIC(int, fwlink_enable) = 0; 83 #define V_fwlink_enable VNET(fwlink_enable) 84 85 int ipfw_chg_hook(SYSCTL_HANDLER_ARGS); 86 87 /* Forward declarations. */ 88 static int ipfw_divert(struct mbuf **, struct ip_fw_args *, bool); 89 90 #ifdef SYSCTL_NODE 91 92 SYSBEGIN(f1) 93 94 SYSCTL_DECL(_net_inet_ip_fw); 95 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, enable, 96 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3 | 97 CTLFLAG_NEEDGIANT, &VNET_NAME(fw_enable), 0, ipfw_chg_hook, "I", 98 "Enable ipfw"); 99 #ifdef INET6 100 SYSCTL_DECL(_net_inet6_ip6_fw); 101 SYSCTL_PROC(_net_inet6_ip6_fw, OID_AUTO, enable, 102 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3 | 103 CTLFLAG_NEEDGIANT, &VNET_NAME(fw6_enable), 0, ipfw_chg_hook, "I", 104 "Enable ipfw+6"); 105 #endif /* INET6 */ 106 107 SYSCTL_DECL(_net_link_ether); 108 SYSCTL_PROC(_net_link_ether, OID_AUTO, ipfw, 109 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3 | 110 CTLFLAG_NEEDGIANT, &VNET_NAME(fwlink_enable), 0, ipfw_chg_hook, "I", 111 "Pass ether pkts through firewall"); 112 113 SYSEND 114 115 #endif /* SYSCTL_NODE */ 116 117 /* 118 * The pfilter hook to pass packets to ipfw_chk and then to 119 * dummynet, divert, netgraph or other modules. 120 * The packet may be consumed. 121 */ 122 static pfil_return_t 123 ipfw_check_packet(struct mbuf **m0, struct ifnet *ifp, int flags, 124 void *ruleset __unused, struct inpcb *inp) 125 { 126 struct ip_fw_args args; 127 struct m_tag *tag; 128 pfil_return_t ret; 129 int ipfw; 130 131 args.flags = (flags & PFIL_IN) ? IPFW_ARGS_IN : IPFW_ARGS_OUT; 132 again: 133 /* 134 * extract and remove the tag if present. If we are left 135 * with onepass, optimize the outgoing path. 136 */ 137 tag = m_tag_locate(*m0, MTAG_IPFW_RULE, 0, NULL); 138 if (tag != NULL) { 139 args.rule = *((struct ipfw_rule_ref *)(tag+1)); 140 m_tag_delete(*m0, tag); 141 if (args.rule.info & IPFW_ONEPASS) 142 return (PFIL_PASS); 143 args.flags |= IPFW_ARGS_REF; 144 } 145 146 args.m = *m0; 147 args.ifp = ifp; 148 args.inp = inp; 149 150 ipfw = ipfw_chk(&args); 151 *m0 = args.m; 152 153 KASSERT(*m0 != NULL || ipfw == IP_FW_DENY || 154 ipfw == IP_FW_NAT64, ("%s: m0 is NULL", __func__)); 155 156 ret = PFIL_PASS; 157 switch (ipfw) { 158 case IP_FW_PASS: 159 /* next_hop may be set by ipfw_chk */ 160 if ((args.flags & (IPFW_ARGS_NH4 | IPFW_ARGS_NH4PTR | 161 IPFW_ARGS_NH6 | IPFW_ARGS_NH6PTR)) == 0) 162 break; 163 #if (!defined(INET6) && !defined(INET)) 164 ret = PFIL_DROPPED; 165 #else 166 { 167 void *psa; 168 size_t len; 169 #ifdef INET 170 if (args.flags & (IPFW_ARGS_NH4 | IPFW_ARGS_NH4PTR)) { 171 MPASS((args.flags & (IPFW_ARGS_NH4 | 172 IPFW_ARGS_NH4PTR)) != (IPFW_ARGS_NH4 | 173 IPFW_ARGS_NH4PTR)); 174 MPASS((args.flags & (IPFW_ARGS_NH6 | 175 IPFW_ARGS_NH6PTR)) == 0); 176 len = sizeof(struct sockaddr_in); 177 psa = (args.flags & IPFW_ARGS_NH4) ? 178 &args.hopstore : args.next_hop; 179 if (in_localip(satosin(psa)->sin_addr)) 180 (*m0)->m_flags |= M_FASTFWD_OURS; 181 (*m0)->m_flags |= M_IP_NEXTHOP; 182 } 183 #endif /* INET */ 184 #ifdef INET6 185 if (args.flags & (IPFW_ARGS_NH6 | IPFW_ARGS_NH6PTR)) { 186 MPASS((args.flags & (IPFW_ARGS_NH6 | 187 IPFW_ARGS_NH6PTR)) != (IPFW_ARGS_NH6 | 188 IPFW_ARGS_NH6PTR)); 189 MPASS((args.flags & (IPFW_ARGS_NH4 | 190 IPFW_ARGS_NH4PTR)) == 0); 191 len = sizeof(struct sockaddr_in6); 192 psa = args.next_hop6; 193 (*m0)->m_flags |= M_IP6_NEXTHOP; 194 } 195 #endif /* INET6 */ 196 /* 197 * Incoming packets should not be tagged so we do not 198 * m_tag_find. Outgoing packets may be tagged, so we 199 * reuse the tag if present. 200 */ 201 tag = (flags & PFIL_IN) ? NULL : 202 m_tag_find(*m0, PACKET_TAG_IPFORWARD, NULL); 203 if (tag != NULL) { 204 m_tag_unlink(*m0, tag); 205 } else { 206 tag = m_tag_get(PACKET_TAG_IPFORWARD, len, 207 M_NOWAIT); 208 if (tag == NULL) { 209 ret = PFIL_DROPPED; 210 break; 211 } 212 } 213 if ((args.flags & IPFW_ARGS_NH6) == 0) 214 bcopy(psa, tag + 1, len); 215 m_tag_prepend(*m0, tag); 216 ret = PFIL_PASS; 217 #ifdef INET6 218 /* IPv6 next hop needs additional handling */ 219 if (args.flags & (IPFW_ARGS_NH6 | IPFW_ARGS_NH6PTR)) { 220 struct sockaddr_in6 *sa6; 221 222 sa6 = satosin6(tag + 1); 223 if (args.flags & IPFW_ARGS_NH6) { 224 sa6->sin6_family = AF_INET6; 225 sa6->sin6_len = sizeof(*sa6); 226 sa6->sin6_addr = args.hopstore6.sin6_addr; 227 sa6->sin6_port = args.hopstore6.sin6_port; 228 sa6->sin6_scope_id = 229 args.hopstore6.sin6_scope_id; 230 } 231 /* 232 * If nh6 address is link-local we should convert 233 * it to kernel internal form before doing any 234 * comparisons. 235 */ 236 if (sa6_embedscope(sa6, V_ip6_use_defzone) != 0) { 237 ret = PFIL_DROPPED; 238 break; 239 } 240 if (in6_localip(&sa6->sin6_addr)) 241 (*m0)->m_flags |= M_FASTFWD_OURS; 242 } 243 #endif /* INET6 */ 244 } 245 #endif /* INET || INET6 */ 246 break; 247 248 case IP_FW_DENY: 249 ret = PFIL_DROPPED; 250 break; 251 252 case IP_FW_DUMMYNET: 253 if (ip_dn_io_ptr == NULL) { 254 ret = PFIL_DROPPED; 255 break; 256 } 257 MPASS(args.flags & IPFW_ARGS_REF); 258 if (args.flags & (IPFW_ARGS_IP4 | IPFW_ARGS_IP6)) 259 (void )ip_dn_io_ptr(m0, &args); 260 else { 261 ret = PFIL_DROPPED; 262 break; 263 } 264 /* 265 * XXX should read the return value. 266 * dummynet normally eats the packet and sets *m0=NULL 267 * unless the packet can be sent immediately. In this 268 * case args is updated and we should re-run the 269 * check without clearing args. 270 */ 271 if (*m0 != NULL) 272 goto again; 273 ret = PFIL_CONSUMED; 274 break; 275 276 case IP_FW_TEE: 277 case IP_FW_DIVERT: 278 if (ip_divert_ptr == NULL) { 279 ret = PFIL_DROPPED; 280 break; 281 } 282 MPASS(args.flags & IPFW_ARGS_REF); 283 (void )ipfw_divert(m0, &args, ipfw == IP_FW_TEE); 284 /* continue processing for the original packet (tee). */ 285 if (*m0) 286 goto again; 287 ret = PFIL_CONSUMED; 288 break; 289 290 case IP_FW_NGTEE: 291 case IP_FW_NETGRAPH: 292 if (ng_ipfw_input_p == NULL) { 293 ret = PFIL_DROPPED; 294 break; 295 } 296 MPASS(args.flags & IPFW_ARGS_REF); 297 (void )ng_ipfw_input_p(m0, &args, ipfw == IP_FW_NGTEE); 298 if (ipfw == IP_FW_NGTEE) /* ignore errors for NGTEE */ 299 goto again; /* continue with packet */ 300 ret = PFIL_CONSUMED; 301 break; 302 303 case IP_FW_NAT: 304 /* honor one-pass in case of successful nat */ 305 if (V_fw_one_pass) 306 break; 307 goto again; 308 309 case IP_FW_REASS: 310 goto again; /* continue with packet */ 311 312 case IP_FW_NAT64: 313 ret = PFIL_CONSUMED; 314 break; 315 316 default: 317 KASSERT(0, ("%s: unknown retval", __func__)); 318 } 319 320 if (ret != PFIL_PASS) { 321 if (*m0) 322 FREE_PKT(*m0); 323 *m0 = NULL; 324 } 325 326 return (ret); 327 } 328 329 /* 330 * ipfw processing for ethernet packets (in and out), mbuf version. 331 */ 332 static pfil_return_t 333 ipfw_check_frame_mbuf(struct mbuf **m0, struct ifnet *ifp, const int flags, 334 void *ruleset __unused, struct inpcb *inp) 335 { 336 struct ip_fw_args args = { 337 .flags = IPFW_ARGS_ETHER | 338 ((flags & PFIL_IN) ? IPFW_ARGS_IN : IPFW_ARGS_OUT), 339 .ifp = ifp, 340 .inp = inp, 341 }; 342 struct m_tag *mtag; 343 pfil_return_t ret; 344 int ipfw; 345 346 again: 347 /* 348 * Fetch start point from rule, if any. 349 * Remove the tag if present. 350 */ 351 mtag = m_tag_locate(*m0, MTAG_IPFW_RULE, 0, NULL); 352 if (mtag != NULL) { 353 args.rule = *((struct ipfw_rule_ref *)(mtag+1)); 354 m_tag_delete(*m0, mtag); 355 if (args.rule.info & IPFW_ONEPASS) 356 return (PFIL_PASS); 357 args.flags |= IPFW_ARGS_REF; 358 } 359 args.m = *m0, 360 361 ipfw = ipfw_chk(&args); 362 *m0 = args.m; 363 364 ret = PFIL_PASS; 365 switch (ipfw) { 366 case IP_FW_PASS: 367 break; 368 369 case IP_FW_DENY: 370 ret = PFIL_DROPPED; 371 break; 372 373 case IP_FW_DUMMYNET: 374 if (ip_dn_io_ptr == NULL) { 375 ret = PFIL_DROPPED; 376 break; 377 } 378 MPASS(args.flags & IPFW_ARGS_REF); 379 ip_dn_io_ptr(m0, &args); 380 return (PFIL_CONSUMED); 381 382 case IP_FW_NGTEE: 383 case IP_FW_NETGRAPH: 384 if (ng_ipfw_input_p == NULL) { 385 ret = PFIL_DROPPED; 386 break; 387 } 388 MPASS(args.flags & IPFW_ARGS_REF); 389 (void )ng_ipfw_input_p(m0, &args, ipfw == IP_FW_NGTEE); 390 if (ipfw == IP_FW_NGTEE) /* ignore errors for NGTEE */ 391 goto again; /* continue with packet */ 392 ret = PFIL_CONSUMED; 393 break; 394 395 default: 396 KASSERT(0, ("%s: unknown retval", __func__)); 397 } 398 399 if (ret != PFIL_PASS) { 400 if (*m0) 401 FREE_PKT(*m0); 402 *m0 = NULL; 403 } 404 405 return (ret); 406 } 407 408 /* 409 * ipfw processing for ethernet packets (in and out), memory pointer version, 410 * two in/out accessors. 411 */ 412 static pfil_return_t 413 ipfw_check_frame_mem(void *mem, u_int len, int flags, struct ifnet *ifp, 414 void *ruleset __unused, struct mbuf **m) 415 { 416 struct ip_fw_args args = { 417 .flags = len | IPFW_ARGS_ETHER | 418 ((flags & PFIL_IN) ? IPFW_ARGS_IN : IPFW_ARGS_OUT), 419 .ifp = ifp, 420 .mem = mem, 421 }; 422 pfil_return_t ret; 423 int ipfw; 424 425 *m = NULL; 426 again: 427 ipfw = ipfw_chk(&args); 428 429 ret = PFIL_PASS; 430 switch (ipfw) { 431 case IP_FW_PASS: 432 break; 433 434 case IP_FW_DENY: 435 ret = PFIL_DROPPED; 436 break; 437 438 case IP_FW_DUMMYNET: 439 if (ip_dn_io_ptr == NULL) { 440 ret = PFIL_DROPPED; 441 break; 442 } 443 *m = m_devget(mem, len, 0, ifp, NULL); 444 if (*m == NULL) { 445 ret = PFIL_DROPPED; 446 break; 447 } 448 MPASS(args.flags & IPFW_ARGS_REF); 449 ip_dn_io_ptr(m, &args); 450 return (PFIL_CONSUMED); 451 452 case IP_FW_NGTEE: 453 case IP_FW_NETGRAPH: 454 if (ng_ipfw_input_p == NULL) { 455 ret = PFIL_DROPPED; 456 break; 457 } 458 *m = m_devget(mem, len, 0, ifp, NULL); 459 if (*m == NULL) { 460 ret = PFIL_DROPPED; 461 break; 462 } 463 MPASS(args.flags & IPFW_ARGS_REF); 464 (void )ng_ipfw_input_p(m, &args, ipfw == IP_FW_NGTEE); 465 if (ipfw == IP_FW_NGTEE) /* ignore errors for NGTEE */ 466 goto again; /* continue with packet */ 467 ret = PFIL_CONSUMED; 468 break; 469 470 default: 471 KASSERT(0, ("%s: unknown retval", __func__)); 472 } 473 474 if (*m != NULL && ret == PFIL_PASS) 475 ret = PFIL_REALLOCED; 476 477 return (ret); 478 } 479 480 /* do the divert, return 1 on error 0 on success */ 481 static int 482 ipfw_divert(struct mbuf **m0, struct ip_fw_args *args, bool tee) 483 { 484 /* 485 * ipfw_chk() has already tagged the packet with the divert tag. 486 * If tee is set, copy packet and return original. 487 * If not tee, consume packet and send it to divert socket. 488 */ 489 struct mbuf *clone; 490 struct ip *ip = mtod(*m0, struct ip *); 491 struct m_tag *tag; 492 493 /* Cloning needed for tee? */ 494 if (tee == false) { 495 clone = *m0; /* use the original mbuf */ 496 *m0 = NULL; 497 } else { 498 clone = m_dup(*m0, M_NOWAIT); 499 /* If we cannot duplicate the mbuf, we sacrifice the divert 500 * chain and continue with the tee-ed packet. 501 */ 502 if (clone == NULL) 503 return 1; 504 } 505 506 /* 507 * Divert listeners can normally handle non-fragmented packets, 508 * but we can only reass in the non-tee case. 509 * This means that listeners on a tee rule may get fragments, 510 * and have to live with that. 511 * Note that we now have the 'reass' ipfw option so if we care 512 * we can do it before a 'tee'. 513 */ 514 if (tee == false) switch (ip->ip_v) { 515 case IPVERSION: 516 if (ntohs(ip->ip_off) & (IP_MF | IP_OFFMASK)) { 517 int hlen; 518 struct mbuf *reass; 519 520 reass = ip_reass(clone); /* Reassemble packet. */ 521 if (reass == NULL) 522 return 0; /* not an error */ 523 /* if reass = NULL then it was consumed by ip_reass */ 524 /* 525 * IP header checksum fixup after reassembly and leave header 526 * in network byte order. 527 */ 528 ip = mtod(reass, struct ip *); 529 hlen = ip->ip_hl << 2; 530 ip->ip_sum = 0; 531 if (hlen == sizeof(struct ip)) 532 ip->ip_sum = in_cksum_hdr(ip); 533 else 534 ip->ip_sum = in_cksum(reass, hlen); 535 clone = reass; 536 } 537 break; 538 #ifdef INET6 539 case IPV6_VERSION >> 4: 540 { 541 struct ip6_hdr *const ip6 = mtod(clone, struct ip6_hdr *); 542 543 if (ip6->ip6_nxt == IPPROTO_FRAGMENT) { 544 int nxt, off; 545 546 off = sizeof(struct ip6_hdr); 547 nxt = frag6_input(&clone, &off, 0); 548 if (nxt == IPPROTO_DONE) 549 return (0); 550 } 551 break; 552 } 553 #endif 554 } 555 556 /* attach a tag to the packet with the reinject info */ 557 tag = m_tag_alloc(MTAG_IPFW_RULE, 0, 558 sizeof(struct ipfw_rule_ref), M_NOWAIT); 559 if (tag == NULL) { 560 FREE_PKT(clone); 561 return 1; 562 } 563 *((struct ipfw_rule_ref *)(tag+1)) = args->rule; 564 m_tag_prepend(clone, tag); 565 566 /* Do the dirty job... */ 567 ip_divert_ptr(clone, args->flags & IPFW_ARGS_IN); 568 return 0; 569 } 570 571 /* 572 * attach or detach hooks for a given protocol family 573 */ 574 VNET_DEFINE_STATIC(pfil_hook_t, ipfw_inet_hook); 575 #define V_ipfw_inet_hook VNET(ipfw_inet_hook) 576 #ifdef INET6 577 VNET_DEFINE_STATIC(pfil_hook_t, ipfw_inet6_hook); 578 #define V_ipfw_inet6_hook VNET(ipfw_inet6_hook) 579 #endif 580 VNET_DEFINE_STATIC(pfil_hook_t, ipfw_link_hook); 581 #define V_ipfw_link_hook VNET(ipfw_link_hook) 582 583 static void 584 ipfw_hook(int pf) 585 { 586 struct pfil_hook_args pha = { 587 .pa_version = PFIL_VERSION, 588 .pa_flags = PFIL_IN | PFIL_OUT, 589 .pa_modname = "ipfw", 590 }; 591 pfil_hook_t *h; 592 593 switch (pf) { 594 case AF_INET: 595 pha.pa_mbuf_chk = ipfw_check_packet; 596 pha.pa_type = PFIL_TYPE_IP4; 597 pha.pa_rulname = "default"; 598 h = &V_ipfw_inet_hook; 599 break; 600 #ifdef INET6 601 case AF_INET6: 602 pha.pa_mbuf_chk = ipfw_check_packet; 603 pha.pa_type = PFIL_TYPE_IP6; 604 pha.pa_rulname = "default6"; 605 h = &V_ipfw_inet6_hook; 606 break; 607 #endif 608 case AF_LINK: 609 pha.pa_mbuf_chk = ipfw_check_frame_mbuf; 610 pha.pa_mem_chk = ipfw_check_frame_mem; 611 pha.pa_type = PFIL_TYPE_ETHERNET; 612 pha.pa_rulname = "default-link"; 613 h = &V_ipfw_link_hook; 614 break; 615 } 616 617 *h = pfil_add_hook(&pha); 618 } 619 620 static void 621 ipfw_unhook(int pf) 622 { 623 624 switch (pf) { 625 case AF_INET: 626 pfil_remove_hook(V_ipfw_inet_hook); 627 break; 628 #ifdef INET6 629 case AF_INET6: 630 pfil_remove_hook(V_ipfw_inet6_hook); 631 break; 632 #endif 633 case AF_LINK: 634 pfil_remove_hook(V_ipfw_link_hook); 635 break; 636 } 637 } 638 639 static int 640 ipfw_link(int pf, bool unlink) 641 { 642 struct pfil_link_args pla; 643 644 pla.pa_version = PFIL_VERSION; 645 pla.pa_flags = PFIL_IN | PFIL_OUT | PFIL_HEADPTR | PFIL_HOOKPTR; 646 if (unlink) 647 pla.pa_flags |= PFIL_UNLINK; 648 649 switch (pf) { 650 case AF_INET: 651 pla.pa_head = V_inet_pfil_head; 652 pla.pa_hook = V_ipfw_inet_hook; 653 break; 654 #ifdef INET6 655 case AF_INET6: 656 pla.pa_head = V_inet6_pfil_head; 657 pla.pa_hook = V_ipfw_inet6_hook; 658 break; 659 #endif 660 case AF_LINK: 661 pla.pa_head = V_link_pfil_head; 662 pla.pa_hook = V_ipfw_link_hook; 663 break; 664 } 665 666 return (pfil_link(&pla)); 667 } 668 669 int 670 ipfw_attach_hooks(void) 671 { 672 int error = 0; 673 674 ipfw_hook(AF_INET); 675 TUNABLE_INT_FETCH("net.inet.ip.fw.enable", &V_fw_enable); 676 if (V_fw_enable && (error = ipfw_link(AF_INET, false)) != 0) 677 printf("ipfw_hook() error\n"); 678 #ifdef INET6 679 ipfw_hook(AF_INET6); 680 TUNABLE_INT_FETCH("net.inet6.ip6.fw.enable", &V_fw6_enable); 681 if (V_fw6_enable && (error = ipfw_link(AF_INET6, false)) != 0) 682 printf("ipfw6_hook() error\n"); 683 #endif 684 ipfw_hook(AF_LINK); 685 TUNABLE_INT_FETCH("net.link.ether.ipfw", &V_fwlink_enable); 686 if (V_fwlink_enable && (error = ipfw_link(AF_LINK, false)) != 0) 687 printf("ipfw_link_hook() error\n"); 688 689 return (error); 690 } 691 692 void 693 ipfw_detach_hooks(void) 694 { 695 696 ipfw_unhook(AF_INET); 697 #ifdef INET6 698 ipfw_unhook(AF_INET6); 699 #endif 700 ipfw_unhook(AF_LINK); 701 } 702 703 int 704 ipfw_chg_hook(SYSCTL_HANDLER_ARGS) 705 { 706 int newval; 707 int error; 708 int af; 709 710 if (arg1 == &V_fw_enable) 711 af = AF_INET; 712 #ifdef INET6 713 else if (arg1 == &V_fw6_enable) 714 af = AF_INET6; 715 #endif 716 else if (arg1 == &V_fwlink_enable) 717 af = AF_LINK; 718 else 719 return (EINVAL); 720 721 newval = *(int *)arg1; 722 /* Handle sysctl change */ 723 error = sysctl_handle_int(oidp, &newval, 0, req); 724 725 if (error) 726 return (error); 727 728 /* Formalize new value */ 729 newval = (newval) ? 1 : 0; 730 731 if (*(int *)arg1 == newval) 732 return (0); 733 734 error = ipfw_link(af, newval == 0 ? true : false); 735 if (error) 736 return (error); 737 *(int *)arg1 = newval; 738 739 return (0); 740 } 741 /* end of file */ 742