1 /* $FreeBSD: src/sys/netinet6/ip6_fw.c,v 1.2.2.10 2003/08/03 17:52:54 ume Exp $ */ 2 /* $DragonFly: src/sys/net/ip6fw/ip6_fw.c,v 1.19 2008/03/07 11:34:20 sephe Exp $ */ 3 /* $KAME: ip6_fw.c,v 1.21 2001/01/24 01:25:32 itojun Exp $ */ 4 5 /* 6 * Copyright (C) 1998, 1999, 2000 and 2001 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1993 Daniel Boulet 36 * Copyright (c) 1994 Ugen J.S.Antsilevich 37 * Copyright (c) 1996 Alex Nash 38 * 39 * Redistribution and use in source forms, with and without modification, 40 * are permitted provided that this entire comment appears intact. 41 * 42 * Redistribution in binary form may occur without any restrictions. 43 * Obviously, it would be nice if you gave credit where credit is due 44 * but requiring it would be too onerous. 45 * 46 * This software is provided ``AS IS'' without any warranties of any kind. 47 */ 48 49 /* 50 * Implement IPv6 packet firewall 51 */ 52 53 #if !defined(KLD_MODULE) 54 #include "opt_ip6fw.h" 55 #include "opt_inet.h" 56 #include "opt_inet6.h" 57 #endif 58 59 #ifdef IP6DIVERT 60 #error "NOT SUPPORTED IPV6 DIVERT" 61 #endif 62 #ifdef IP6FW_DIVERT_RESTART 63 #error "NOT SUPPORTED IPV6 DIVERT" 64 #endif 65 66 #include <sys/param.h> 67 #include <sys/systm.h> 68 #include <sys/malloc.h> 69 #include <sys/mbuf.h> 70 #include <sys/queue.h> 71 #include <sys/kernel.h> 72 #include <sys/socket.h> 73 #include <sys/socketvar.h> 74 #include <sys/syslog.h> 75 #include <sys/thread2.h> 76 #include <sys/time.h> 77 #include <net/if.h> 78 #include <net/route.h> 79 #include <netinet/in_systm.h> 80 #include <netinet/in.h> 81 #include <netinet/ip.h> 82 83 #include <netinet/ip6.h> 84 #include <netinet6/ip6_var.h> 85 #include <netinet6/in6_var.h> 86 #include <netinet/icmp6.h> 87 88 #include <netinet/in_pcb.h> 89 90 #include "ip6_fw.h" 91 #include <netinet/ip_var.h> 92 #include <netinet/tcp.h> 93 #include <netinet/tcp_seq.h> 94 #include <netinet/tcp_timer.h> 95 #include <netinet/tcp_var.h> 96 #include <netinet/udp.h> 97 98 #include <sys/sysctl.h> 99 100 #include <net/net_osdep.h> 101 102 MALLOC_DEFINE(M_IP6FW, "Ip6Fw/Ip6Acct", "Ip6Fw/Ip6Acct chain's"); 103 104 static int fw6_debug = 1; 105 #ifdef IPV6FIREWALL_VERBOSE 106 static int fw6_verbose = 1; 107 #else 108 static int fw6_verbose = 0; 109 #endif 110 #ifdef IPV6FIREWALL_VERBOSE_LIMIT 111 static int fw6_verbose_limit = IPV6FIREWALL_VERBOSE_LIMIT; 112 #else 113 static int fw6_verbose_limit = 0; 114 #endif 115 116 LIST_HEAD (ip6_fw_head, ip6_fw_chain) ip6_fw_chain; 117 118 #ifdef SYSCTL_NODE 119 SYSCTL_DECL(_net_inet6_ip6); 120 SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall"); 121 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, enable, CTLFLAG_RW, 122 &ip6_fw_enable, 0, "Enable ip6fw"); 123 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, debug, CTLFLAG_RW, &fw6_debug, 0, ""); 124 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, verbose, CTLFLAG_RW, &fw6_verbose, 0, ""); 125 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, verbose_limit, CTLFLAG_RW, &fw6_verbose_limit, 0, ""); 126 #endif 127 128 #define dprintf(a) do { \ 129 if (fw6_debug) \ 130 kprintf a; \ 131 } while (0) 132 #define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0 133 134 static int add_entry6 (struct ip6_fw_head *chainptr, struct ip6_fw *frwl); 135 static int del_entry6 (struct ip6_fw_head *chainptr, u_short number); 136 static int zero_entry6 (struct mbuf *m); 137 static struct ip6_fw *check_ip6fw_struct (struct ip6_fw *m); 138 static struct ip6_fw *check_ip6fw_mbuf (struct mbuf *fw); 139 static int ip6opts_match (struct ip6_hdr **ip6, struct ip6_fw *f, 140 struct mbuf **m, 141 int *off, int *nxt, u_short *offset); 142 static int port_match6 (u_short *portptr, int nports, u_short port, 143 int range_flag); 144 static int tcp6flg_match (struct tcphdr *tcp6, struct ip6_fw *f); 145 static int icmp6type_match (struct icmp6_hdr * icmp, struct ip6_fw * f); 146 static void ip6fw_report (struct ip6_fw *f, struct ip6_hdr *ip6, 147 struct ifnet *rif, struct ifnet *oif, int off, int nxt); 148 149 static int ip6_fw_chk (struct ip6_hdr **pip6, 150 struct ifnet *oif, u_int16_t *cookie, struct mbuf **m); 151 static int ip6_fw_ctl (int stage, struct mbuf **mm); 152 153 static char err_prefix[] = "ip6_fw_ctl:"; 154 155 /* 156 * Returns 1 if the port is matched by the vector, 0 otherwise 157 */ 158 static 159 __inline int 160 port_match6(u_short *portptr, int nports, u_short port, int range_flag) 161 { 162 if (!nports) 163 return 1; 164 if (range_flag) { 165 if (portptr[0] <= port && port <= portptr[1]) { 166 return 1; 167 } 168 nports -= 2; 169 portptr += 2; 170 } 171 while (nports-- > 0) { 172 if (*portptr++ == port) { 173 return 1; 174 } 175 } 176 return 0; 177 } 178 179 static int 180 tcp6flg_match(struct tcphdr *tcp6, struct ip6_fw *f) 181 { 182 u_char flg_set, flg_clr; 183 184 /* 185 * If an established connection is required, reject packets that 186 * have only SYN of RST|ACK|SYN set. Otherwise, fall through to 187 * other flag requirements. 188 */ 189 if ((f->fw_ipflg & IPV6_FW_IF_TCPEST) && 190 ((tcp6->th_flags & (IPV6_FW_TCPF_RST | IPV6_FW_TCPF_ACK | 191 IPV6_FW_TCPF_SYN)) == IPV6_FW_TCPF_SYN)) 192 return 0; 193 194 flg_set = tcp6->th_flags & f->fw_tcpf; 195 flg_clr = tcp6->th_flags & f->fw_tcpnf; 196 197 if (flg_set != f->fw_tcpf) 198 return 0; 199 if (flg_clr) 200 return 0; 201 202 return 1; 203 } 204 205 static int 206 icmp6type_match(struct icmp6_hdr *icmp6, struct ip6_fw *f) 207 { 208 int type; 209 210 if (!(f->fw_flg & IPV6_FW_F_ICMPBIT)) 211 return(1); 212 213 type = icmp6->icmp6_type; 214 215 /* check for matching type in the bitmap */ 216 if (type < IPV6_FW_ICMPTYPES_DIM * sizeof(unsigned) * 8 && 217 (f->fw_icmp6types[type / (sizeof(unsigned) * 8)] & 218 (1U << (type % (8 * sizeof(unsigned)))))) 219 return(1); 220 221 return(0); /* no match */ 222 } 223 224 static int 225 is_icmp6_query(struct ip6_hdr *ip6, int off) 226 { 227 const struct icmp6_hdr *icmp6; 228 int icmp6_type; 229 230 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 231 icmp6_type = icmp6->icmp6_type; 232 233 if (icmp6_type == ICMP6_ECHO_REQUEST || 234 icmp6_type == ICMP6_MEMBERSHIP_QUERY || 235 icmp6_type == ICMP6_WRUREQUEST || 236 icmp6_type == ICMP6_FQDN_QUERY || 237 icmp6_type == ICMP6_NI_QUERY) 238 return(1); 239 240 return(0); 241 } 242 243 static int 244 ip6opts_match(struct ip6_hdr **pip6, struct ip6_fw *f, struct mbuf **m, 245 int *off, int *nxt, u_short *offset) 246 { 247 int len; 248 struct ip6_hdr *ip6 = *pip6; 249 struct ip6_ext *ip6e; 250 u_char opts, nopts, nopts_sve; 251 252 opts = f->fw_ip6opt; 253 nopts = nopts_sve = f->fw_ip6nopt; 254 255 *nxt = ip6->ip6_nxt; 256 *off = sizeof(struct ip6_hdr); 257 len = ntohs(ip6->ip6_plen) + sizeof(struct ip6_hdr); 258 while (*off < len) { 259 ip6e = (struct ip6_ext *)((caddr_t) ip6 + *off); 260 if ((*m)->m_len < *off + sizeof(*ip6e)) 261 goto opts_check; /* XXX */ 262 263 switch(*nxt) { 264 case IPPROTO_FRAGMENT: 265 if ((*m)->m_len >= *off + sizeof(struct ip6_frag)) { 266 struct ip6_frag *ip6f; 267 268 ip6f = (struct ip6_frag *) ((caddr_t)ip6 + *off); 269 *offset = ip6f->ip6f_offlg & IP6F_OFF_MASK; 270 } 271 opts &= ~IPV6_FW_IP6OPT_FRAG; 272 nopts &= ~IPV6_FW_IP6OPT_FRAG; 273 *off += sizeof(struct ip6_frag); 274 break; 275 case IPPROTO_AH: 276 opts &= ~IPV6_FW_IP6OPT_AH; 277 nopts &= ~IPV6_FW_IP6OPT_AH; 278 *off += (ip6e->ip6e_len + 2) << 2; 279 break; 280 default: 281 switch (*nxt) { 282 case IPPROTO_HOPOPTS: 283 opts &= ~IPV6_FW_IP6OPT_HOPOPT; 284 nopts &= ~IPV6_FW_IP6OPT_HOPOPT; 285 break; 286 case IPPROTO_ROUTING: 287 opts &= ~IPV6_FW_IP6OPT_ROUTE; 288 nopts &= ~IPV6_FW_IP6OPT_ROUTE; 289 break; 290 case IPPROTO_ESP: 291 opts &= ~IPV6_FW_IP6OPT_ESP; 292 nopts &= ~IPV6_FW_IP6OPT_ESP; 293 goto opts_check; 294 case IPPROTO_NONE: 295 opts &= ~IPV6_FW_IP6OPT_NONXT; 296 nopts &= ~IPV6_FW_IP6OPT_NONXT; 297 goto opts_check; 298 case IPPROTO_DSTOPTS: 299 opts &= ~IPV6_FW_IP6OPT_OPTS; 300 nopts &= ~IPV6_FW_IP6OPT_OPTS; 301 break; 302 default: 303 goto opts_check; 304 } 305 *off += (ip6e->ip6e_len + 1) << 3; 306 break; 307 } 308 *nxt = ip6e->ip6e_nxt; 309 310 } 311 opts_check: 312 if (f->fw_ip6opt == f->fw_ip6nopt) /* XXX */ 313 return 1; 314 315 if (opts == 0 && nopts == nopts_sve) 316 return 1; 317 else 318 return 0; 319 } 320 321 static 322 __inline int 323 iface_match(struct ifnet *ifp, union ip6_fw_if *ifu, int byname) 324 { 325 /* Check by name or by IP address */ 326 if (byname) { 327 /* Check name */ 328 if (ifu->fu_via_if.glob) { 329 if (kfnmatch(ifu->fu_via_if.name, ifp->if_xname, 0) 330 == FNM_NOMATCH) 331 return(0); 332 } else { 333 if (strncmp(ifp->if_xname, ifu->fu_via_if.name, 334 IP6FW_IFNLEN) != 0) 335 return(0); 336 } 337 return(1); 338 } else if (!IN6_IS_ADDR_UNSPECIFIED(&ifu->fu_via_ip6)) { /* Zero == wildcard */ 339 struct ifaddr_container *ifac; 340 341 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 342 struct ifaddr *ifa = ifac->ifa; 343 344 if (ifa->ifa_addr == NULL) 345 continue; 346 if (ifa->ifa_addr->sa_family != AF_INET6) 347 continue; 348 if (!IN6_ARE_ADDR_EQUAL(&ifu->fu_via_ip6, 349 &(((struct sockaddr_in6 *) 350 (ifa->ifa_addr))->sin6_addr))) 351 continue; 352 return(1); 353 } 354 return(0); 355 } 356 return(1); 357 } 358 359 static void 360 ip6fw_report(struct ip6_fw *f, struct ip6_hdr *ip6, 361 struct ifnet *rif, struct ifnet *oif, int off, int nxt) 362 { 363 static int counter; 364 struct tcphdr *const tcp6 = (struct tcphdr *) ((caddr_t) ip6+ off); 365 struct udphdr *const udp = (struct udphdr *) ((caddr_t) ip6+ off); 366 struct icmp6_hdr *const icmp6 = (struct icmp6_hdr *) ((caddr_t) ip6+ off); 367 int count; 368 char *action; 369 char action2[32], proto[102], name[18]; 370 int len; 371 372 count = f ? f->fw_pcnt : ++counter; 373 if (fw6_verbose_limit != 0 && count > fw6_verbose_limit) 374 return; 375 376 /* Print command name */ 377 ksnprintf(SNPARGS(name, 0), "ip6fw: %d", f ? f->fw_number : -1); 378 379 action = action2; 380 if (!f) 381 action = "Refuse"; 382 else { 383 switch (f->fw_flg & IPV6_FW_F_COMMAND) { 384 case IPV6_FW_F_DENY: 385 action = "Deny"; 386 break; 387 case IPV6_FW_F_REJECT: 388 if (f->fw_reject_code == IPV6_FW_REJECT_RST) 389 action = "Reset"; 390 else 391 action = "Unreach"; 392 break; 393 case IPV6_FW_F_ACCEPT: 394 action = "Accept"; 395 break; 396 case IPV6_FW_F_COUNT: 397 action = "Count"; 398 break; 399 case IPV6_FW_F_DIVERT: 400 ksnprintf(SNPARGS(action2, 0), "Divert %d", 401 f->fw_divert_port); 402 break; 403 case IPV6_FW_F_TEE: 404 ksnprintf(SNPARGS(action2, 0), "Tee %d", 405 f->fw_divert_port); 406 break; 407 case IPV6_FW_F_SKIPTO: 408 ksnprintf(SNPARGS(action2, 0), "SkipTo %d", 409 f->fw_skipto_rule); 410 break; 411 default: 412 action = "UNKNOWN"; 413 break; 414 } 415 } 416 417 switch (nxt) { 418 case IPPROTO_TCP: 419 len = ksnprintf(SNPARGS(proto, 0), "TCP [%s]", 420 ip6_sprintf(&ip6->ip6_src)); 421 if (off > 0) 422 len += ksnprintf(SNPARGS(proto, len), ":%d ", 423 ntohs(tcp6->th_sport)); 424 else 425 len += ksnprintf(SNPARGS(proto, len), " "); 426 len += ksnprintf(SNPARGS(proto, len), "[%s]", 427 ip6_sprintf(&ip6->ip6_dst)); 428 if (off > 0) 429 ksnprintf(SNPARGS(proto, len), ":%d", 430 ntohs(tcp6->th_dport)); 431 break; 432 case IPPROTO_UDP: 433 len = ksnprintf(SNPARGS(proto, 0), "UDP [%s]", 434 ip6_sprintf(&ip6->ip6_src)); 435 if (off > 0) 436 len += ksnprintf(SNPARGS(proto, len), ":%d ", 437 ntohs(udp->uh_sport)); 438 else 439 len += ksnprintf(SNPARGS(proto, len), " "); 440 len += ksnprintf(SNPARGS(proto, len), "[%s]", 441 ip6_sprintf(&ip6->ip6_dst)); 442 if (off > 0) 443 ksnprintf(SNPARGS(proto, len), ":%d", 444 ntohs(udp->uh_dport)); 445 break; 446 case IPPROTO_ICMPV6: 447 if (off > 0) 448 len = ksnprintf(SNPARGS(proto, 0), "IPV6-ICMP:%u.%u ", 449 icmp6->icmp6_type, icmp6->icmp6_code); 450 else 451 len = ksnprintf(SNPARGS(proto, 0), "IPV6-ICMP "); 452 len += ksnprintf(SNPARGS(proto, len), "[%s]", 453 ip6_sprintf(&ip6->ip6_src)); 454 ksnprintf(SNPARGS(proto, len), " [%s]", 455 ip6_sprintf(&ip6->ip6_dst)); 456 break; 457 default: 458 len = ksnprintf(SNPARGS(proto, 0), "P:%d [%s]", nxt, 459 ip6_sprintf(&ip6->ip6_src)); 460 ksnprintf(SNPARGS(proto, len), " [%s]", 461 ip6_sprintf(&ip6->ip6_dst)); 462 break; 463 } 464 465 if (oif) 466 log(LOG_SECURITY | LOG_INFO, "%s %s %s out via %s\n", 467 name, action, proto, if_name(oif)); 468 else if (rif) 469 log(LOG_SECURITY | LOG_INFO, "%s %s %s in via %s\n", 470 name, action, proto, if_name(rif)); 471 else 472 log(LOG_SECURITY | LOG_INFO, "%s %s %s", 473 name, action, proto); 474 if (fw6_verbose_limit != 0 && count == fw6_verbose_limit) 475 log(LOG_SECURITY | LOG_INFO, "ip6fw: limit reached on entry %d\n", 476 f ? f->fw_number : -1); 477 } 478 479 /* 480 * Parameters: 481 * 482 * ip Pointer to packet header (struct ip6_hdr *) 483 * hlen Packet header length 484 * oif Outgoing interface, or NULL if packet is incoming 485 * #ifndef IP6FW_DIVERT_RESTART 486 * *cookie Ignore all divert/tee rules to this port (if non-zero) 487 * #else 488 * *cookie Skip up to the first rule past this rule number; 489 * #endif 490 * *m The packet; we set to NULL when/if we nuke it. 491 * 492 * Return value: 493 * 494 * 0 The packet is to be accepted and routed normally OR 495 * the packet was denied/rejected and has been dropped; 496 * in the latter case, *m is equal to NULL upon return. 497 * port Divert the packet to port. 498 */ 499 500 static int 501 ip6_fw_chk(struct ip6_hdr **pip6, 502 struct ifnet *oif, u_int16_t *cookie, struct mbuf **m) 503 { 504 struct ip6_fw_chain *chain; 505 struct ip6_fw *rule = NULL; 506 struct ip6_hdr *ip6 = *pip6; 507 struct ifnet *const rif = (*m)->m_pkthdr.rcvif; 508 u_short offset = 0; 509 int off = sizeof(struct ip6_hdr), nxt = ip6->ip6_nxt; 510 u_short src_port, dst_port; 511 #ifdef IP6FW_DIVERT_RESTART 512 u_int16_t skipto = *cookie; 513 #else 514 u_int16_t ignport = ntohs(*cookie); 515 #endif 516 517 *cookie = 0; 518 /* 519 * Go down the chain, looking for enlightment 520 * #ifdef IP6FW_DIVERT_RESTART 521 * If we've been asked to start at a given rule immediatly, do so. 522 * #endif 523 */ 524 chain = LIST_FIRST(&ip6_fw_chain); 525 #ifdef IP6FW_DIVERT_RESTART 526 if (skipto) { 527 if (skipto >= 65535) 528 goto dropit; 529 while (chain && (chain->rule->fw_number <= skipto)) { 530 chain = LIST_NEXT(chain, chain); 531 } 532 if (! chain) goto dropit; 533 } 534 #endif /* IP6FW_DIVERT_RESTART */ 535 for (; chain; chain = LIST_NEXT(chain, chain)) { 536 struct ip6_fw *const f = chain->rule; 537 538 if (oif) { 539 /* Check direction outbound */ 540 if (!(f->fw_flg & IPV6_FW_F_OUT)) 541 continue; 542 } else { 543 /* Check direction inbound */ 544 if (!(f->fw_flg & IPV6_FW_F_IN)) 545 continue; 546 } 547 548 #define IN6_ARE_ADDR_MASKEQUAL(x,y,z) (\ 549 (((x)->s6_addr32[0] & (y)->s6_addr32[0]) == (z)->s6_addr32[0]) && \ 550 (((x)->s6_addr32[1] & (y)->s6_addr32[1]) == (z)->s6_addr32[1]) && \ 551 (((x)->s6_addr32[2] & (y)->s6_addr32[2]) == (z)->s6_addr32[2]) && \ 552 (((x)->s6_addr32[3] & (y)->s6_addr32[3]) == (z)->s6_addr32[3])) 553 554 /* If src-addr doesn't match, not this rule. */ 555 if (((f->fw_flg & IPV6_FW_F_INVSRC) != 0) ^ 556 (!IN6_ARE_ADDR_MASKEQUAL(&ip6->ip6_src,&f->fw_smsk,&f->fw_src))) 557 continue; 558 559 /* If dest-addr doesn't match, not this rule. */ 560 if (((f->fw_flg & IPV6_FW_F_INVDST) != 0) ^ 561 (!IN6_ARE_ADDR_MASKEQUAL(&ip6->ip6_dst,&f->fw_dmsk,&f->fw_dst))) 562 continue; 563 564 #undef IN6_ARE_ADDR_MASKEQUAL 565 /* Interface check */ 566 if ((f->fw_flg & IF6_FW_F_VIAHACK) == IF6_FW_F_VIAHACK) { 567 struct ifnet *const iface = oif ? oif : rif; 568 569 /* Backwards compatibility hack for "via" */ 570 if (!iface || !iface_match(iface, 571 &f->fw_in_if, f->fw_flg & IPV6_FW_F_OIFNAME)) 572 continue; 573 } else { 574 /* Check receive interface */ 575 if ((f->fw_flg & IPV6_FW_F_IIFACE) 576 && (!rif || !iface_match(rif, 577 &f->fw_in_if, f->fw_flg & IPV6_FW_F_IIFNAME))) 578 continue; 579 /* Check outgoing interface */ 580 if ((f->fw_flg & IPV6_FW_F_OIFACE) 581 && (!oif || !iface_match(oif, 582 &f->fw_out_if, f->fw_flg & IPV6_FW_F_OIFNAME))) 583 continue; 584 } 585 586 /* Check IP options */ 587 if (!ip6opts_match(&ip6, f, m, &off, &nxt, &offset)) 588 continue; 589 590 /* Fragments */ 591 if ((f->fw_flg & IPV6_FW_F_FRAG) && !offset) 592 continue; 593 594 /* Check protocol; if wildcard, match */ 595 if (f->fw_prot == IPPROTO_IPV6) 596 goto got_match; 597 598 /* If different, don't match */ 599 if (nxt != f->fw_prot) 600 continue; 601 602 #define PULLUP_TO(len) do { \ 603 if ((*m)->m_len < (len) \ 604 && (*m = m_pullup(*m, (len))) == 0) { \ 605 goto dropit; \ 606 } \ 607 *pip6 = ip6 = mtod(*m, struct ip6_hdr *); \ 608 } while (0) 609 610 /* Protocol specific checks */ 611 switch (nxt) { 612 case IPPROTO_TCP: 613 { 614 struct tcphdr *tcp6; 615 616 if (offset == 1) { /* cf. RFC 1858 */ 617 PULLUP_TO(off + 4); /* XXX ? */ 618 goto bogusfrag; 619 } 620 if (offset != 0) { 621 /* 622 * TCP flags and ports aren't available in this 623 * packet -- if this rule specified either one, 624 * we consider the rule a non-match. 625 */ 626 if (f->fw_nports != 0 || 627 f->fw_tcpf != f->fw_tcpnf) 628 continue; 629 630 break; 631 } 632 PULLUP_TO(off + 14); 633 tcp6 = (struct tcphdr *) ((caddr_t)ip6 + off); 634 if (((f->fw_tcpf != f->fw_tcpnf) || 635 (f->fw_ipflg & IPV6_FW_IF_TCPEST)) && 636 !tcp6flg_match(tcp6, f)) 637 continue; 638 src_port = ntohs(tcp6->th_sport); 639 dst_port = ntohs(tcp6->th_dport); 640 goto check_ports; 641 } 642 643 case IPPROTO_UDP: 644 { 645 struct udphdr *udp; 646 647 if (offset != 0) { 648 /* 649 * Port specification is unavailable -- if this 650 * rule specifies a port, we consider the rule 651 * a non-match. 652 */ 653 if (f->fw_nports != 0) 654 continue; 655 656 break; 657 } 658 PULLUP_TO(off + 4); 659 udp = (struct udphdr *) ((caddr_t)ip6 + off); 660 src_port = ntohs(udp->uh_sport); 661 dst_port = ntohs(udp->uh_dport); 662 check_ports: 663 if (!port_match6(&f->fw_pts[0], 664 IPV6_FW_GETNSRCP(f), src_port, 665 f->fw_flg & IPV6_FW_F_SRNG)) 666 continue; 667 if (!port_match6(&f->fw_pts[IPV6_FW_GETNSRCP(f)], 668 IPV6_FW_GETNDSTP(f), dst_port, 669 f->fw_flg & IPV6_FW_F_DRNG)) 670 continue; 671 break; 672 } 673 674 case IPPROTO_ICMPV6: 675 { 676 struct icmp6_hdr *icmp; 677 678 if (offset != 0) /* Type isn't valid */ 679 break; 680 PULLUP_TO(off + 2); 681 icmp = (struct icmp6_hdr *) ((caddr_t)ip6 + off); 682 if (!icmp6type_match(icmp, f)) 683 continue; 684 break; 685 } 686 #undef PULLUP_TO 687 688 bogusfrag: 689 if (fw6_verbose) 690 ip6fw_report(NULL, ip6, rif, oif, off, nxt); 691 goto dropit; 692 } 693 694 got_match: 695 #ifndef IP6FW_DIVERT_RESTART 696 /* Ignore divert/tee rule if socket port is "ignport" */ 697 switch (f->fw_flg & IPV6_FW_F_COMMAND) { 698 case IPV6_FW_F_DIVERT: 699 case IPV6_FW_F_TEE: 700 if (f->fw_divert_port == ignport) 701 continue; /* ignore this rule */ 702 break; 703 } 704 705 #endif /* IP6FW_DIVERT_RESTART */ 706 /* Update statistics */ 707 f->fw_pcnt += 1; 708 f->fw_bcnt += ntohs(ip6->ip6_plen); 709 f->timestamp = time_second; 710 711 /* Log to console if desired */ 712 if ((f->fw_flg & IPV6_FW_F_PRN) && fw6_verbose) 713 ip6fw_report(f, ip6, rif, oif, off, nxt); 714 715 /* Take appropriate action */ 716 switch (f->fw_flg & IPV6_FW_F_COMMAND) { 717 case IPV6_FW_F_ACCEPT: 718 return(0); 719 case IPV6_FW_F_COUNT: 720 continue; 721 case IPV6_FW_F_DIVERT: 722 #ifdef IP6FW_DIVERT_RESTART 723 *cookie = f->fw_number; 724 #else 725 *cookie = htons(f->fw_divert_port); 726 #endif /* IP6FW_DIVERT_RESTART */ 727 return(f->fw_divert_port); 728 case IPV6_FW_F_TEE: 729 /* 730 * XXX someday tee packet here, but beware that you 731 * can't use m_copym() or m_copypacket() because 732 * the divert input routine modifies the mbuf 733 * (and these routines only increment reference 734 * counts in the case of mbuf clusters), so need 735 * to write custom routine. 736 */ 737 continue; 738 case IPV6_FW_F_SKIPTO: 739 #ifdef DIAGNOSTIC 740 while (chain->chain.le_next 741 && chain->chain.le_next->rule->fw_number 742 < f->fw_skipto_rule) 743 #else 744 while (chain->chain.le_next->rule->fw_number 745 < f->fw_skipto_rule) 746 #endif 747 chain = chain->chain.le_next; 748 continue; 749 } 750 751 /* Deny/reject this packet using this rule */ 752 rule = f; 753 break; 754 } 755 756 #ifdef DIAGNOSTIC 757 /* Rule 65535 should always be there and should always match */ 758 if (!chain) 759 panic("ip6_fw: chain"); 760 #endif 761 762 /* 763 * At this point, we're going to drop the packet. 764 * Send a reject notice if all of the following are true: 765 * 766 * - The packet matched a reject rule 767 * - The packet is not an ICMP packet, or is an ICMP query packet 768 * - The packet is not a multicast or broadcast packet 769 */ 770 if ((rule->fw_flg & IPV6_FW_F_COMMAND) == IPV6_FW_F_REJECT 771 && (nxt != IPPROTO_ICMPV6 || is_icmp6_query(ip6, off)) 772 && !((*m)->m_flags & (M_BCAST|M_MCAST)) 773 && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 774 switch (rule->fw_reject_code) { 775 case IPV6_FW_REJECT_RST: 776 { 777 struct tcphdr *const tcp = 778 (struct tcphdr *) ((caddr_t)ip6 + off); 779 struct { 780 struct ip6_hdr ip6; 781 struct tcphdr th; 782 } ti; 783 tcp_seq ack, seq; 784 int flags; 785 786 if (offset != 0 || (tcp->th_flags & TH_RST)) 787 break; 788 789 ti.ip6 = *ip6; 790 ti.th = *tcp; 791 ti.th.th_seq = ntohl(ti.th.th_seq); 792 ti.th.th_ack = ntohl(ti.th.th_ack); 793 ti.ip6.ip6_nxt = IPPROTO_TCP; 794 if (ti.th.th_flags & TH_ACK) { 795 ack = 0; 796 seq = ti.th.th_ack; 797 flags = TH_RST; 798 } else { 799 ack = ti.th.th_seq; 800 if (((*m)->m_flags & M_PKTHDR) != 0) { 801 ack += (*m)->m_pkthdr.len - off 802 - (ti.th.th_off << 2); 803 } else if (ip6->ip6_plen) { 804 ack += ntohs(ip6->ip6_plen) + sizeof(*ip6) 805 - off - (ti.th.th_off << 2); 806 } else { 807 m_freem(*m); 808 *m = 0; 809 break; 810 } 811 seq = 0; 812 flags = TH_RST|TH_ACK; 813 } 814 bcopy(&ti, ip6, sizeof(ti)); 815 tcp_respond(NULL, ip6, (struct tcphdr *)(ip6 + 1), 816 *m, ack, seq, flags); 817 *m = NULL; 818 break; 819 } 820 default: /* Send an ICMP unreachable using code */ 821 if (oif) 822 (*m)->m_pkthdr.rcvif = oif; 823 icmp6_error(*m, ICMP6_DST_UNREACH, 824 rule->fw_reject_code, 0); 825 *m = NULL; 826 break; 827 } 828 } 829 830 dropit: 831 /* 832 * Finally, drop the packet. 833 */ 834 if (*m) { 835 m_freem(*m); 836 *m = NULL; 837 } 838 return(0); 839 } 840 841 static int 842 add_entry6(struct ip6_fw_head *chainptr, struct ip6_fw *frwl) 843 { 844 struct ip6_fw *ftmp = 0; 845 struct ip6_fw_chain *fwc = 0, *fcp, *fcpl = 0; 846 u_short nbr = 0; 847 848 fwc = kmalloc(sizeof *fwc, M_IP6FW, M_INTWAIT); 849 ftmp = kmalloc(sizeof *ftmp, M_IP6FW, M_INTWAIT); 850 851 bcopy(frwl, ftmp, sizeof(struct ip6_fw)); 852 ftmp->fw_in_if.fu_via_if.name[IP6FW_IFNLEN - 1] = '\0'; 853 ftmp->fw_pcnt = 0L; 854 ftmp->fw_bcnt = 0L; 855 fwc->rule = ftmp; 856 857 crit_enter(); 858 859 if (!chainptr->lh_first) { 860 LIST_INSERT_HEAD(chainptr, fwc, chain); 861 crit_exit(); 862 return(0); 863 } else if (ftmp->fw_number == (u_short)-1) { 864 if (fwc) kfree(fwc, M_IP6FW); 865 if (ftmp) kfree(ftmp, M_IP6FW); 866 crit_exit(); 867 dprintf(("%s bad rule number\n", err_prefix)); 868 return (EINVAL); 869 } 870 871 /* If entry number is 0, find highest numbered rule and add 100 */ 872 if (ftmp->fw_number == 0) { 873 for (fcp = chainptr->lh_first; fcp; fcp = fcp->chain.le_next) { 874 if (fcp->rule->fw_number != (u_short)-1) 875 nbr = fcp->rule->fw_number; 876 else 877 break; 878 } 879 if (nbr < (u_short)-1 - 100) 880 nbr += 100; 881 ftmp->fw_number = nbr; 882 } 883 884 /* Got a valid number; now insert it, keeping the list ordered */ 885 for (fcp = chainptr->lh_first; fcp; fcp = fcp->chain.le_next) { 886 if (fcp->rule->fw_number > ftmp->fw_number) { 887 if (fcpl) { 888 LIST_INSERT_AFTER(fcpl, fwc, chain); 889 } else { 890 LIST_INSERT_HEAD(chainptr, fwc, chain); 891 } 892 break; 893 } else { 894 fcpl = fcp; 895 } 896 } 897 898 crit_exit(); 899 return (0); 900 } 901 902 static int 903 del_entry6(struct ip6_fw_head *chainptr, u_short number) 904 { 905 struct ip6_fw_chain *fcp; 906 907 crit_enter(); 908 909 fcp = chainptr->lh_first; 910 if (number != (u_short)-1) { 911 for (; fcp; fcp = fcp->chain.le_next) { 912 if (fcp->rule->fw_number == number) { 913 LIST_REMOVE(fcp, chain); 914 crit_exit(); 915 kfree(fcp->rule, M_IP6FW); 916 kfree(fcp, M_IP6FW); 917 return 0; 918 } 919 } 920 } 921 922 crit_exit(); 923 return (EINVAL); 924 } 925 926 static int 927 zero_entry6(struct mbuf *m) 928 { 929 struct ip6_fw *frwl; 930 struct ip6_fw_chain *fcp; 931 932 if (m && m->m_len != 0) { 933 if (m->m_len != sizeof(struct ip6_fw)) 934 return(EINVAL); 935 frwl = mtod(m, struct ip6_fw *); 936 } 937 else 938 frwl = NULL; 939 940 /* 941 * It's possible to insert multiple chain entries with the 942 * same number, so we don't stop after finding the first 943 * match if zeroing a specific entry. 944 */ 945 crit_enter(); 946 for (fcp = ip6_fw_chain.lh_first; fcp; fcp = fcp->chain.le_next) 947 if (!frwl || frwl->fw_number == fcp->rule->fw_number) { 948 fcp->rule->fw_bcnt = fcp->rule->fw_pcnt = 0; 949 fcp->rule->timestamp = 0; 950 } 951 crit_exit(); 952 953 if (fw6_verbose) { 954 if (frwl) 955 log(LOG_SECURITY | LOG_NOTICE, 956 "ip6fw: Entry %d cleared.\n", frwl->fw_number); 957 else 958 log(LOG_SECURITY | LOG_NOTICE, 959 "ip6fw: Accounting cleared.\n"); 960 } 961 962 return(0); 963 } 964 965 static struct ip6_fw * 966 check_ip6fw_mbuf(struct mbuf *m) 967 { 968 /* Check length */ 969 if (m->m_len != sizeof(struct ip6_fw)) { 970 dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len, 971 (int)sizeof(struct ip6_fw))); 972 return (NULL); 973 } 974 return(check_ip6fw_struct(mtod(m, struct ip6_fw *))); 975 } 976 977 static struct ip6_fw * 978 check_ip6fw_struct(struct ip6_fw *frwl) 979 { 980 /* Check for invalid flag bits */ 981 if ((frwl->fw_flg & ~IPV6_FW_F_MASK) != 0) { 982 dprintf(("%s undefined flag bits set (flags=%x)\n", 983 err_prefix, frwl->fw_flg)); 984 return (NULL); 985 } 986 /* Must apply to incoming or outgoing (or both) */ 987 if (!(frwl->fw_flg & (IPV6_FW_F_IN | IPV6_FW_F_OUT))) { 988 dprintf(("%s neither in nor out\n", err_prefix)); 989 return (NULL); 990 } 991 /* Empty interface name is no good */ 992 if (((frwl->fw_flg & IPV6_FW_F_IIFNAME) 993 && !*frwl->fw_in_if.fu_via_if.name) 994 || ((frwl->fw_flg & IPV6_FW_F_OIFNAME) 995 && !*frwl->fw_out_if.fu_via_if.name)) { 996 dprintf(("%s empty interface name\n", err_prefix)); 997 return (NULL); 998 } 999 /* Sanity check interface matching */ 1000 if ((frwl->fw_flg & IF6_FW_F_VIAHACK) == IF6_FW_F_VIAHACK) { 1001 ; /* allow "via" backwards compatibility */ 1002 } else if ((frwl->fw_flg & IPV6_FW_F_IN) 1003 && (frwl->fw_flg & IPV6_FW_F_OIFACE)) { 1004 dprintf(("%s outgoing interface check on incoming\n", 1005 err_prefix)); 1006 return (NULL); 1007 } 1008 /* Sanity check port ranges */ 1009 if ((frwl->fw_flg & IPV6_FW_F_SRNG) && IPV6_FW_GETNSRCP(frwl) < 2) { 1010 dprintf(("%s src range set but n_src_p=%d\n", 1011 err_prefix, IPV6_FW_GETNSRCP(frwl))); 1012 return (NULL); 1013 } 1014 if ((frwl->fw_flg & IPV6_FW_F_DRNG) && IPV6_FW_GETNDSTP(frwl) < 2) { 1015 dprintf(("%s dst range set but n_dst_p=%d\n", 1016 err_prefix, IPV6_FW_GETNDSTP(frwl))); 1017 return (NULL); 1018 } 1019 if (IPV6_FW_GETNSRCP(frwl) + IPV6_FW_GETNDSTP(frwl) > IPV6_FW_MAX_PORTS) { 1020 dprintf(("%s too many ports (%d+%d)\n", 1021 err_prefix, IPV6_FW_GETNSRCP(frwl), IPV6_FW_GETNDSTP(frwl))); 1022 return (NULL); 1023 } 1024 /* 1025 * Protocols other than TCP/UDP don't use port range 1026 */ 1027 if ((frwl->fw_prot != IPPROTO_TCP) && 1028 (frwl->fw_prot != IPPROTO_UDP) && 1029 (IPV6_FW_GETNSRCP(frwl) || IPV6_FW_GETNDSTP(frwl))) { 1030 dprintf(("%s port(s) specified for non TCP/UDP rule\n", 1031 err_prefix)); 1032 return(NULL); 1033 } 1034 1035 /* 1036 * Rather than modify the entry to make such entries work, 1037 * we reject this rule and require user level utilities 1038 * to enforce whatever policy they deem appropriate. 1039 */ 1040 if ((frwl->fw_src.s6_addr32[0] & (~frwl->fw_smsk.s6_addr32[0])) || 1041 (frwl->fw_src.s6_addr32[1] & (~frwl->fw_smsk.s6_addr32[1])) || 1042 (frwl->fw_src.s6_addr32[2] & (~frwl->fw_smsk.s6_addr32[2])) || 1043 (frwl->fw_src.s6_addr32[3] & (~frwl->fw_smsk.s6_addr32[3])) || 1044 (frwl->fw_dst.s6_addr32[0] & (~frwl->fw_dmsk.s6_addr32[0])) || 1045 (frwl->fw_dst.s6_addr32[1] & (~frwl->fw_dmsk.s6_addr32[1])) || 1046 (frwl->fw_dst.s6_addr32[2] & (~frwl->fw_dmsk.s6_addr32[2])) || 1047 (frwl->fw_dst.s6_addr32[3] & (~frwl->fw_dmsk.s6_addr32[3]))) { 1048 dprintf(("%s rule never matches\n", err_prefix)); 1049 return(NULL); 1050 } 1051 1052 if ((frwl->fw_flg & IPV6_FW_F_FRAG) && 1053 (frwl->fw_prot == IPPROTO_UDP || frwl->fw_prot == IPPROTO_TCP)) { 1054 if (frwl->fw_nports) { 1055 dprintf(("%s cannot mix 'frag' and ports\n", err_prefix)); 1056 return(NULL); 1057 } 1058 if (frwl->fw_prot == IPPROTO_TCP && 1059 frwl->fw_tcpf != frwl->fw_tcpnf) { 1060 dprintf(("%s cannot mix 'frag' with TCP flags\n", err_prefix)); 1061 return(NULL); 1062 } 1063 } 1064 1065 /* Check command specific stuff */ 1066 switch (frwl->fw_flg & IPV6_FW_F_COMMAND) 1067 { 1068 case IPV6_FW_F_REJECT: 1069 if (frwl->fw_reject_code >= 0x100 1070 && !(frwl->fw_prot == IPPROTO_TCP 1071 && frwl->fw_reject_code == IPV6_FW_REJECT_RST)) { 1072 dprintf(("%s unknown reject code\n", err_prefix)); 1073 return(NULL); 1074 } 1075 break; 1076 case IPV6_FW_F_DIVERT: /* Diverting to port zero is invalid */ 1077 case IPV6_FW_F_TEE: 1078 if (frwl->fw_divert_port == 0) { 1079 dprintf(("%s can't divert to port 0\n", err_prefix)); 1080 return (NULL); 1081 } 1082 break; 1083 case IPV6_FW_F_DENY: 1084 case IPV6_FW_F_ACCEPT: 1085 case IPV6_FW_F_COUNT: 1086 case IPV6_FW_F_SKIPTO: 1087 break; 1088 default: 1089 dprintf(("%s invalid command\n", err_prefix)); 1090 return(NULL); 1091 } 1092 1093 return frwl; 1094 } 1095 1096 static int 1097 ip6_fw_ctl(int stage, struct mbuf **mm) 1098 { 1099 int error; 1100 struct mbuf *m; 1101 1102 if (stage == IPV6_FW_GET) { 1103 struct ip6_fw_chain *fcp = ip6_fw_chain.lh_first; 1104 *mm = m = m_get(MB_WAIT, MT_DATA); /* XXX */ 1105 if (!m) 1106 return(ENOBUFS); 1107 if (sizeof *(fcp->rule) > MLEN) { 1108 MCLGET(m, MB_WAIT); 1109 if ((m->m_flags & M_EXT) == 0) { 1110 m_free(m); 1111 return(ENOBUFS); 1112 } 1113 } 1114 for (; fcp; fcp = fcp->chain.le_next) { 1115 bcopy(fcp->rule, m->m_data, sizeof *(fcp->rule)); 1116 m->m_len = sizeof *(fcp->rule); 1117 m->m_next = m_get(MB_WAIT, MT_DATA); /* XXX */ 1118 if (!m->m_next) { 1119 m_freem(*mm); 1120 return(ENOBUFS); 1121 } 1122 m = m->m_next; 1123 if (sizeof *(fcp->rule) > MLEN) { 1124 MCLGET(m, MB_WAIT); 1125 if ((m->m_flags & M_EXT) == 0) { 1126 m_freem(*mm); 1127 return(ENOBUFS); 1128 } 1129 } 1130 m->m_len = 0; 1131 } 1132 return (0); 1133 } 1134 m = *mm; 1135 /* only allow get calls if secure mode > 2 */ 1136 if (securelevel > 2) { 1137 if (m) { 1138 m_freem(m); 1139 *mm = 0; 1140 } 1141 return(EPERM); 1142 } 1143 if (stage == IPV6_FW_FLUSH) { 1144 while (ip6_fw_chain.lh_first != NULL && 1145 ip6_fw_chain.lh_first->rule->fw_number != (u_short)-1) { 1146 struct ip6_fw_chain *fcp = ip6_fw_chain.lh_first; 1147 crit_enter(); 1148 LIST_REMOVE(ip6_fw_chain.lh_first, chain); 1149 crit_exit(); 1150 kfree(fcp->rule, M_IP6FW); 1151 kfree(fcp, M_IP6FW); 1152 } 1153 if (m) { 1154 m_freem(m); 1155 *mm = 0; 1156 } 1157 return (0); 1158 } 1159 if (stage == IPV6_FW_ZERO) { 1160 error = zero_entry6(m); 1161 if (m) { 1162 m_freem(m); 1163 *mm = 0; 1164 } 1165 return (error); 1166 } 1167 if (m == NULL) { 1168 kprintf("%s NULL mbuf ptr\n", err_prefix); 1169 return (EINVAL); 1170 } 1171 1172 if (stage == IPV6_FW_ADD) { 1173 struct ip6_fw *frwl = check_ip6fw_mbuf(m); 1174 1175 if (!frwl) 1176 error = EINVAL; 1177 else 1178 error = add_entry6(&ip6_fw_chain, frwl); 1179 if (m) { 1180 m_freem(m); 1181 *mm = 0; 1182 } 1183 return error; 1184 } 1185 if (stage == IPV6_FW_DEL) { 1186 if (m->m_len != sizeof(struct ip6_fw)) { 1187 dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len, 1188 (int)sizeof(struct ip6_fw))); 1189 error = EINVAL; 1190 } else if (mtod(m, struct ip6_fw *)->fw_number == (u_short)-1) { 1191 dprintf(("%s can't delete rule 65535\n", err_prefix)); 1192 error = EINVAL; 1193 } else 1194 error = del_entry6(&ip6_fw_chain, 1195 mtod(m, struct ip6_fw *)->fw_number); 1196 if (m) { 1197 m_freem(m); 1198 *mm = 0; 1199 } 1200 return error; 1201 } 1202 1203 dprintf(("%s unknown request %d\n", err_prefix, stage)); 1204 if (m) { 1205 m_freem(m); 1206 *mm = 0; 1207 } 1208 return (EINVAL); 1209 } 1210 1211 void 1212 ip6_fw_init(void) 1213 { 1214 struct ip6_fw default_rule; 1215 1216 ip6_fw_chk_ptr = ip6_fw_chk; 1217 ip6_fw_ctl_ptr = ip6_fw_ctl; 1218 LIST_INIT(&ip6_fw_chain); 1219 1220 bzero(&default_rule, sizeof default_rule); 1221 default_rule.fw_prot = IPPROTO_IPV6; 1222 default_rule.fw_number = (u_short)-1; 1223 #ifdef IPV6FIREWALL_DEFAULT_TO_ACCEPT 1224 default_rule.fw_flg |= IPV6_FW_F_ACCEPT; 1225 #else 1226 default_rule.fw_flg |= IPV6_FW_F_DENY; 1227 #endif 1228 default_rule.fw_flg |= IPV6_FW_F_IN | IPV6_FW_F_OUT; 1229 if (check_ip6fw_struct(&default_rule) == NULL || 1230 add_entry6(&ip6_fw_chain, &default_rule)) 1231 panic(__func__); 1232 1233 kprintf("IPv6 packet filtering initialized, "); 1234 #ifdef IPV6FIREWALL_DEFAULT_TO_ACCEPT 1235 kprintf("default to accept, "); 1236 #endif 1237 #ifndef IPV6FIREWALL_VERBOSE 1238 kprintf("logging disabled\n"); 1239 #else 1240 if (fw6_verbose_limit == 0) 1241 kprintf("unlimited logging\n"); 1242 else 1243 kprintf("logging limited to %d packets/entry\n", 1244 fw6_verbose_limit); 1245 #endif 1246 } 1247 1248 static ip6_fw_chk_t *old_chk_ptr; 1249 static ip6_fw_ctl_t *old_ctl_ptr; 1250 1251 static int 1252 ip6fw_modevent(module_t mod, int type, void *unused) 1253 { 1254 switch (type) { 1255 case MOD_LOAD: 1256 crit_enter(); 1257 1258 old_chk_ptr = ip6_fw_chk_ptr; 1259 old_ctl_ptr = ip6_fw_ctl_ptr; 1260 1261 ip6_fw_init(); 1262 crit_exit(); 1263 return 0; 1264 case MOD_UNLOAD: 1265 crit_enter(); 1266 ip6_fw_chk_ptr = old_chk_ptr; 1267 ip6_fw_ctl_ptr = old_ctl_ptr; 1268 while (LIST_FIRST(&ip6_fw_chain) != NULL) { 1269 struct ip6_fw_chain *fcp = LIST_FIRST(&ip6_fw_chain); 1270 LIST_REMOVE(LIST_FIRST(&ip6_fw_chain), chain); 1271 kfree(fcp->rule, M_IP6FW); 1272 kfree(fcp, M_IP6FW); 1273 } 1274 1275 crit_exit(); 1276 kprintf("IPv6 firewall unloaded\n"); 1277 return 0; 1278 default: 1279 break; 1280 } 1281 return 0; 1282 } 1283 1284 static moduledata_t ip6fwmod = { 1285 "ip6fw", 1286 ip6fw_modevent, 1287 0 1288 }; 1289 DECLARE_MODULE(ip6fw, ip6fwmod, SI_SUB_PSEUDO, SI_ORDER_ANY); 1290