1 /* $FreeBSD: src/sys/netinet6/ip6_fw.c,v 1.2.2.9 2002/04/28 05:40:27 suz Exp $ */ 2 /* $DragonFly: src/sys/net/ip6fw/ip6_fw.c,v 1.10 2004/08/02 13:22:33 joerg 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/time.h> 76 #include <net/if.h> 77 #include <net/route.h> 78 #include <netinet/in_systm.h> 79 #include <netinet/in.h> 80 #include <netinet/ip.h> 81 82 #include <netinet/ip6.h> 83 #include <netinet6/ip6_var.h> 84 #include <netinet6/in6_var.h> 85 #include <netinet/icmp6.h> 86 87 #include <netinet/in_pcb.h> 88 89 #include "ip6_fw.h" 90 #include <netinet/ip_var.h> 91 #include <netinet/tcp.h> 92 #include <netinet/tcp_seq.h> 93 #include <netinet/tcp_timer.h> 94 #include <netinet/tcp_var.h> 95 #include <netinet/udp.h> 96 97 #include <sys/sysctl.h> 98 99 #include <net/net_osdep.h> 100 101 MALLOC_DEFINE(M_IP6FW, "Ip6Fw/Ip6Acct", "Ip6Fw/Ip6Acct chain's"); 102 103 static int fw6_debug = 1; 104 #ifdef IPV6FIREWALL_VERBOSE 105 static int fw6_verbose = 1; 106 #else 107 static int fw6_verbose = 0; 108 #endif 109 #ifdef IPV6FIREWALL_VERBOSE_LIMIT 110 static int fw6_verbose_limit = IPV6FIREWALL_VERBOSE_LIMIT; 111 #else 112 static int fw6_verbose_limit = 0; 113 #endif 114 115 LIST_HEAD (ip6_fw_head, ip6_fw_chain) ip6_fw_chain; 116 117 #ifdef SYSCTL_NODE 118 SYSCTL_DECL(_net_inet6_ip6); 119 SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall"); 120 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, enable, CTLFLAG_RW, 121 &ip6_fw_enable, 0, "Enable ip6fw"); 122 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, debug, CTLFLAG_RW, &fw6_debug, 0, ""); 123 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, verbose, CTLFLAG_RW, &fw6_verbose, 0, ""); 124 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, verbose_limit, CTLFLAG_RW, &fw6_verbose_limit, 0, ""); 125 #endif 126 127 #define dprintf(a) do { \ 128 if (fw6_debug) \ 129 printf a; \ 130 } while (0) 131 #define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0 132 133 static int add_entry6 (struct ip6_fw_head *chainptr, struct ip6_fw *frwl); 134 static int del_entry6 (struct ip6_fw_head *chainptr, u_short number); 135 static int zero_entry6 (struct mbuf *m); 136 static struct ip6_fw *check_ip6fw_struct (struct ip6_fw *m); 137 static struct ip6_fw *check_ip6fw_mbuf (struct mbuf *fw); 138 static int ip6opts_match (struct ip6_hdr **ip6, struct ip6_fw *f, 139 struct mbuf **m, 140 int *off, int *nxt, u_short *offset); 141 static int port_match6 (u_short *portptr, int nports, u_short port, 142 int range_flag); 143 static int tcp6flg_match (struct tcphdr *tcp6, struct ip6_fw *f); 144 static int icmp6type_match (struct icmp6_hdr * icmp, struct ip6_fw * f); 145 static void ip6fw_report (struct ip6_fw *f, struct ip6_hdr *ip6, 146 struct ifnet *rif, struct ifnet *oif, int off, int nxt); 147 148 static int ip6_fw_chk (struct ip6_hdr **pip6, 149 struct ifnet *oif, u_int16_t *cookie, struct mbuf **m); 150 static int ip6_fw_ctl (int stage, struct mbuf **mm); 151 152 static char err_prefix[] = "ip6_fw_ctl:"; 153 154 /* 155 * Returns 1 if the port is matched by the vector, 0 otherwise 156 */ 157 static 158 __inline int 159 port_match6(u_short *portptr, int nports, u_short port, int range_flag) 160 { 161 if (!nports) 162 return 1; 163 if (range_flag) { 164 if (portptr[0] <= port && port <= portptr[1]) { 165 return 1; 166 } 167 nports -= 2; 168 portptr += 2; 169 } 170 while (nports-- > 0) { 171 if (*portptr++ == port) { 172 return 1; 173 } 174 } 175 return 0; 176 } 177 178 static int 179 tcp6flg_match(struct tcphdr *tcp6, struct ip6_fw *f) 180 { 181 u_char flg_set, flg_clr; 182 183 /* 184 * If an established connection is required, reject packets that 185 * have only SYN of RST|ACK|SYN set. Otherwise, fall through to 186 * other flag requirements. 187 */ 188 if ((f->fw_ipflg & IPV6_FW_IF_TCPEST) && 189 ((tcp6->th_flags & (IPV6_FW_TCPF_RST | IPV6_FW_TCPF_ACK | 190 IPV6_FW_TCPF_SYN)) == IPV6_FW_TCPF_SYN)) 191 return 0; 192 193 flg_set = tcp6->th_flags & f->fw_tcpf; 194 flg_clr = tcp6->th_flags & f->fw_tcpnf; 195 196 if (flg_set != f->fw_tcpf) 197 return 0; 198 if (flg_clr) 199 return 0; 200 201 return 1; 202 } 203 204 static int 205 icmp6type_match(struct icmp6_hdr *icmp6, struct ip6_fw *f) 206 { 207 int type; 208 209 if (!(f->fw_flg & IPV6_FW_F_ICMPBIT)) 210 return(1); 211 212 type = icmp6->icmp6_type; 213 214 /* check for matching type in the bitmap */ 215 if (type < IPV6_FW_ICMPTYPES_DIM * sizeof(unsigned) * 8 && 216 (f->fw_icmp6types[type / (sizeof(unsigned) * 8)] & 217 (1U << (type % (8 * sizeof(unsigned)))))) 218 return(1); 219 220 return(0); /* no match */ 221 } 222 223 static int 224 is_icmp6_query(struct ip6_hdr *ip6, int off) 225 { 226 const struct icmp6_hdr *icmp6; 227 int icmp6_type; 228 229 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 230 icmp6_type = icmp6->icmp6_type; 231 232 if (icmp6_type == ICMP6_ECHO_REQUEST || 233 icmp6_type == ICMP6_MEMBERSHIP_QUERY || 234 icmp6_type == ICMP6_WRUREQUEST || 235 icmp6_type == ICMP6_FQDN_QUERY || 236 icmp6_type == ICMP6_NI_QUERY) 237 return(1); 238 239 return(0); 240 } 241 242 static int 243 ip6opts_match(struct ip6_hdr **pip6, struct ip6_fw *f, struct mbuf **m, 244 int *off, int *nxt, u_short *offset) 245 { 246 int len; 247 struct ip6_hdr *ip6 = *pip6; 248 struct ip6_ext *ip6e; 249 u_char opts, nopts, nopts_sve; 250 251 opts = f->fw_ip6opt; 252 nopts = nopts_sve = f->fw_ip6nopt; 253 254 *nxt = ip6->ip6_nxt; 255 *off = sizeof(struct ip6_hdr); 256 len = ntohs(ip6->ip6_plen) + sizeof(struct ip6_hdr); 257 while (*off < len) { 258 ip6e = (struct ip6_ext *)((caddr_t) ip6 + *off); 259 if ((*m)->m_len < *off + sizeof(*ip6e)) 260 goto opts_check; /* XXX */ 261 262 switch(*nxt) { 263 case IPPROTO_FRAGMENT: 264 if ((*m)->m_len >= *off + sizeof(struct ip6_frag)) { 265 struct ip6_frag *ip6f; 266 267 ip6f = (struct ip6_frag *) ((caddr_t)ip6 + *off); 268 *offset = ip6f->ip6f_offlg & IP6F_OFF_MASK; 269 } 270 opts &= ~IPV6_FW_IP6OPT_FRAG; 271 nopts &= ~IPV6_FW_IP6OPT_FRAG; 272 *off += sizeof(struct ip6_frag); 273 break; 274 case IPPROTO_AH: 275 opts &= ~IPV6_FW_IP6OPT_AH; 276 nopts &= ~IPV6_FW_IP6OPT_AH; 277 *off += (ip6e->ip6e_len + 2) << 2; 278 break; 279 default: 280 switch (*nxt) { 281 case IPPROTO_HOPOPTS: 282 opts &= ~IPV6_FW_IP6OPT_HOPOPT; 283 nopts &= ~IPV6_FW_IP6OPT_HOPOPT; 284 break; 285 case IPPROTO_ROUTING: 286 opts &= ~IPV6_FW_IP6OPT_ROUTE; 287 nopts &= ~IPV6_FW_IP6OPT_ROUTE; 288 break; 289 case IPPROTO_ESP: 290 opts &= ~IPV6_FW_IP6OPT_ESP; 291 nopts &= ~IPV6_FW_IP6OPT_ESP; 292 break; 293 case IPPROTO_NONE: 294 opts &= ~IPV6_FW_IP6OPT_NONXT; 295 nopts &= ~IPV6_FW_IP6OPT_NONXT; 296 goto opts_check; 297 break; 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 break; 305 } 306 *off += (ip6e->ip6e_len + 1) << 3; 307 break; 308 } 309 *nxt = ip6e->ip6e_nxt; 310 311 } 312 opts_check: 313 if (f->fw_ip6opt == f->fw_ip6nopt) /* XXX */ 314 return 1; 315 316 if (opts == 0 && nopts == nopts_sve) 317 return 1; 318 else 319 return 0; 320 } 321 322 static 323 __inline int 324 iface_match(struct ifnet *ifp, union ip6_fw_if *ifu, int byname) 325 { 326 /* Check by name or by IP address */ 327 if (byname) { 328 /* Check name */ 329 if (ifu->fu_via_if.glob) { 330 if (fnmatch(ifu->fu_via_if.name, ifp->if_xname, 0) 331 == FNM_NOMATCH) 332 return(0); 333 } else { 334 if (strncmp(ifp->if_xname, ifu->fu_via_if.name, 335 IP6FW_IFNLEN) != 0) 336 return(0); 337 } 338 return(1); 339 } else if (!IN6_IS_ADDR_UNSPECIFIED(&ifu->fu_via_ip6)) { /* Zero == wildcard */ 340 struct ifaddr *ifa; 341 342 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 343 if (ifa->ifa_addr == NULL) 344 continue; 345 if (ifa->ifa_addr->sa_family != AF_INET6) 346 continue; 347 if (!IN6_ARE_ADDR_EQUAL(&ifu->fu_via_ip6, 348 &(((struct sockaddr_in6 *) 349 (ifa->ifa_addr))->sin6_addr))) 350 continue; 351 return(1); 352 } 353 return(0); 354 } 355 return(1); 356 } 357 358 static void 359 ip6fw_report(struct ip6_fw *f, struct ip6_hdr *ip6, 360 struct ifnet *rif, struct ifnet *oif, int off, int nxt) 361 { 362 static int counter; 363 struct tcphdr *const tcp6 = (struct tcphdr *) ((caddr_t) ip6+ off); 364 struct udphdr *const udp = (struct udphdr *) ((caddr_t) ip6+ off); 365 struct icmp6_hdr *const icmp6 = (struct icmp6_hdr *) ((caddr_t) ip6+ off); 366 int count; 367 char *action; 368 char action2[32], proto[102], name[18]; 369 int len; 370 371 count = f ? f->fw_pcnt : ++counter; 372 if (fw6_verbose_limit != 0 && count > fw6_verbose_limit) 373 return; 374 375 /* Print command name */ 376 snprintf(SNPARGS(name, 0), "ip6fw: %d", f ? f->fw_number : -1); 377 378 action = action2; 379 if (!f) 380 action = "Refuse"; 381 else { 382 switch (f->fw_flg & IPV6_FW_F_COMMAND) { 383 case IPV6_FW_F_DENY: 384 action = "Deny"; 385 break; 386 case IPV6_FW_F_REJECT: 387 if (f->fw_reject_code == IPV6_FW_REJECT_RST) 388 action = "Reset"; 389 else 390 action = "Unreach"; 391 break; 392 case IPV6_FW_F_ACCEPT: 393 action = "Accept"; 394 break; 395 case IPV6_FW_F_COUNT: 396 action = "Count"; 397 break; 398 case IPV6_FW_F_DIVERT: 399 snprintf(SNPARGS(action2, 0), "Divert %d", 400 f->fw_divert_port); 401 break; 402 case IPV6_FW_F_TEE: 403 snprintf(SNPARGS(action2, 0), "Tee %d", 404 f->fw_divert_port); 405 break; 406 case IPV6_FW_F_SKIPTO: 407 snprintf(SNPARGS(action2, 0), "SkipTo %d", 408 f->fw_skipto_rule); 409 break; 410 default: 411 action = "UNKNOWN"; 412 break; 413 } 414 } 415 416 switch (nxt) { 417 case IPPROTO_TCP: 418 len = snprintf(SNPARGS(proto, 0), "TCP [%s]", 419 ip6_sprintf(&ip6->ip6_src)); 420 if (off > 0) 421 len += snprintf(SNPARGS(proto, len), ":%d ", 422 ntohs(tcp6->th_sport)); 423 else 424 len += snprintf(SNPARGS(proto, len), " "); 425 len += snprintf(SNPARGS(proto, len), "[%s]", 426 ip6_sprintf(&ip6->ip6_dst)); 427 if (off > 0) 428 snprintf(SNPARGS(proto, len), ":%d", 429 ntohs(tcp6->th_dport)); 430 break; 431 case IPPROTO_UDP: 432 len = snprintf(SNPARGS(proto, 0), "UDP [%s]", 433 ip6_sprintf(&ip6->ip6_src)); 434 if (off > 0) 435 len += snprintf(SNPARGS(proto, len), ":%d ", 436 ntohs(udp->uh_sport)); 437 else 438 len += snprintf(SNPARGS(proto, len), " "); 439 len += snprintf(SNPARGS(proto, len), "[%s]", 440 ip6_sprintf(&ip6->ip6_dst)); 441 if (off > 0) 442 snprintf(SNPARGS(proto, len), ":%d", 443 ntohs(udp->uh_dport)); 444 break; 445 case IPPROTO_ICMPV6: 446 if (off > 0) 447 len = snprintf(SNPARGS(proto, 0), "IPV6-ICMP:%u.%u ", 448 icmp6->icmp6_type, icmp6->icmp6_code); 449 else 450 len = snprintf(SNPARGS(proto, 0), "IPV6-ICMP "); 451 len += snprintf(SNPARGS(proto, len), "[%s]", 452 ip6_sprintf(&ip6->ip6_src)); 453 snprintf(SNPARGS(proto, len), " [%s]", 454 ip6_sprintf(&ip6->ip6_dst)); 455 break; 456 default: 457 len = snprintf(SNPARGS(proto, 0), "P:%d [%s]", nxt, 458 ip6_sprintf(&ip6->ip6_src)); 459 snprintf(SNPARGS(proto, len), " [%s]", 460 ip6_sprintf(&ip6->ip6_dst)); 461 break; 462 } 463 464 if (oif) 465 log(LOG_SECURITY | LOG_INFO, "%s %s %s out via %s\n", 466 name, action, proto, if_name(oif)); 467 else if (rif) 468 log(LOG_SECURITY | LOG_INFO, "%s %s %s in via %s\n", 469 name, action, proto, if_name(rif)); 470 else 471 log(LOG_SECURITY | LOG_INFO, "%s %s %s", 472 name, action, proto); 473 if (fw6_verbose_limit != 0 && count == fw6_verbose_limit) 474 log(LOG_SECURITY | LOG_INFO, "ip6fw: limit reached on entry %d\n", 475 f ? f->fw_number : -1); 476 } 477 478 /* 479 * Parameters: 480 * 481 * ip Pointer to packet header (struct ip6_hdr *) 482 * hlen Packet header length 483 * oif Outgoing interface, or NULL if packet is incoming 484 * #ifndef IP6FW_DIVERT_RESTART 485 * *cookie Ignore all divert/tee rules to this port (if non-zero) 486 * #else 487 * *cookie Skip up to the first rule past this rule number; 488 * #endif 489 * *m The packet; we set to NULL when/if we nuke it. 490 * 491 * Return value: 492 * 493 * 0 The packet is to be accepted and routed normally OR 494 * the packet was denied/rejected and has been dropped; 495 * in the latter case, *m is equal to NULL upon return. 496 * port Divert the packet to port. 497 */ 498 499 static int 500 ip6_fw_chk(struct ip6_hdr **pip6, 501 struct ifnet *oif, u_int16_t *cookie, struct mbuf **m) 502 { 503 struct ip6_fw_chain *chain; 504 struct ip6_fw *rule = NULL; 505 struct ip6_hdr *ip6 = *pip6; 506 struct ifnet *const rif = (*m)->m_pkthdr.rcvif; 507 u_short offset = 0; 508 int off = sizeof(struct ip6_hdr), nxt = ip6->ip6_nxt; 509 u_short src_port, dst_port; 510 #ifdef IP6FW_DIVERT_RESTART 511 u_int16_t skipto = *cookie; 512 #else 513 u_int16_t ignport = ntohs(*cookie); 514 #endif 515 516 *cookie = 0; 517 /* 518 * Go down the chain, looking for enlightment 519 * #ifdef IP6FW_DIVERT_RESTART 520 * If we've been asked to start at a given rule immediatly, do so. 521 * #endif 522 */ 523 chain = LIST_FIRST(&ip6_fw_chain); 524 #ifdef IP6FW_DIVERT_RESTART 525 if (skipto) { 526 if (skipto >= 65535) 527 goto dropit; 528 while (chain && (chain->rule->fw_number <= skipto)) { 529 chain = LIST_NEXT(chain, chain); 530 } 531 if (! chain) goto dropit; 532 } 533 #endif /* IP6FW_DIVERT_RESTART */ 534 for (; chain; chain = LIST_NEXT(chain, chain)) { 535 struct ip6_fw *const f = chain->rule; 536 537 if (oif) { 538 /* Check direction outbound */ 539 if (!(f->fw_flg & IPV6_FW_F_OUT)) 540 continue; 541 } else { 542 /* Check direction inbound */ 543 if (!(f->fw_flg & IPV6_FW_F_IN)) 544 continue; 545 } 546 547 #define IN6_ARE_ADDR_MASKEQUAL(x,y,z) (\ 548 (((x)->s6_addr32[0] & (y)->s6_addr32[0]) == (z)->s6_addr32[0]) && \ 549 (((x)->s6_addr32[1] & (y)->s6_addr32[1]) == (z)->s6_addr32[1]) && \ 550 (((x)->s6_addr32[2] & (y)->s6_addr32[2]) == (z)->s6_addr32[2]) && \ 551 (((x)->s6_addr32[3] & (y)->s6_addr32[3]) == (z)->s6_addr32[3])) 552 553 /* If src-addr doesn't match, not this rule. */ 554 if (((f->fw_flg & IPV6_FW_F_INVSRC) != 0) ^ 555 (!IN6_ARE_ADDR_MASKEQUAL(&ip6->ip6_src,&f->fw_smsk,&f->fw_src))) 556 continue; 557 558 /* If dest-addr doesn't match, not this rule. */ 559 if (((f->fw_flg & IPV6_FW_F_INVDST) != 0) ^ 560 (!IN6_ARE_ADDR_MASKEQUAL(&ip6->ip6_dst,&f->fw_dmsk,&f->fw_dst))) 561 continue; 562 563 #undef IN6_ARE_ADDR_MASKEQUAL 564 /* Interface check */ 565 if ((f->fw_flg & IF6_FW_F_VIAHACK) == IF6_FW_F_VIAHACK) { 566 struct ifnet *const iface = oif ? oif : rif; 567 568 /* Backwards compatibility hack for "via" */ 569 if (!iface || !iface_match(iface, 570 &f->fw_in_if, f->fw_flg & IPV6_FW_F_OIFNAME)) 571 continue; 572 } else { 573 /* Check receive interface */ 574 if ((f->fw_flg & IPV6_FW_F_IIFACE) 575 && (!rif || !iface_match(rif, 576 &f->fw_in_if, f->fw_flg & IPV6_FW_F_IIFNAME))) 577 continue; 578 /* Check outgoing interface */ 579 if ((f->fw_flg & IPV6_FW_F_OIFACE) 580 && (!oif || !iface_match(oif, 581 &f->fw_out_if, f->fw_flg & IPV6_FW_F_OIFNAME))) 582 continue; 583 } 584 585 /* Check IP options */ 586 if (!ip6opts_match(&ip6, f, m, &off, &nxt, &offset)) 587 continue; 588 589 /* Fragments */ 590 if ((f->fw_flg & IPV6_FW_F_FRAG) && !offset) 591 continue; 592 593 /* Check protocol; if wildcard, match */ 594 if (f->fw_prot == IPPROTO_IPV6) 595 goto got_match; 596 597 /* If different, don't match */ 598 if (nxt != f->fw_prot) 599 continue; 600 601 #define PULLUP_TO(len) do { \ 602 if ((*m)->m_len < (len) \ 603 && (*m = m_pullup(*m, (len))) == 0) { \ 604 goto dropit; \ 605 } \ 606 *pip6 = ip6 = mtod(*m, struct ip6_hdr *); \ 607 } while (0) 608 609 /* Protocol specific checks */ 610 switch (nxt) { 611 case IPPROTO_TCP: 612 { 613 struct tcphdr *tcp6; 614 615 if (offset == 1) { /* cf. RFC 1858 */ 616 PULLUP_TO(off + 4); /* XXX ? */ 617 goto bogusfrag; 618 } 619 if (offset != 0) { 620 /* 621 * TCP flags and ports aren't available in this 622 * packet -- if this rule specified either one, 623 * we consider the rule a non-match. 624 */ 625 if (f->fw_nports != 0 || 626 f->fw_tcpf != f->fw_tcpnf) 627 continue; 628 629 break; 630 } 631 PULLUP_TO(off + 14); 632 tcp6 = (struct tcphdr *) ((caddr_t)ip6 + off); 633 if (((f->fw_tcpf != f->fw_tcpnf) || 634 (f->fw_ipflg & IPV6_FW_IF_TCPEST)) && 635 !tcp6flg_match(tcp6, f)) 636 continue; 637 src_port = ntohs(tcp6->th_sport); 638 dst_port = ntohs(tcp6->th_dport); 639 goto check_ports; 640 } 641 642 case IPPROTO_UDP: 643 { 644 struct udphdr *udp; 645 646 if (offset != 0) { 647 /* 648 * Port specification is unavailable -- if this 649 * rule specifies a port, we consider the rule 650 * a non-match. 651 */ 652 if (f->fw_nports != 0) 653 continue; 654 655 break; 656 } 657 PULLUP_TO(off + 4); 658 udp = (struct udphdr *) ((caddr_t)ip6 + off); 659 src_port = ntohs(udp->uh_sport); 660 dst_port = ntohs(udp->uh_dport); 661 check_ports: 662 if (!port_match6(&f->fw_pts[0], 663 IPV6_FW_GETNSRCP(f), src_port, 664 f->fw_flg & IPV6_FW_F_SRNG)) 665 continue; 666 if (!port_match6(&f->fw_pts[IPV6_FW_GETNSRCP(f)], 667 IPV6_FW_GETNDSTP(f), dst_port, 668 f->fw_flg & IPV6_FW_F_DRNG)) 669 continue; 670 break; 671 } 672 673 case IPPROTO_ICMPV6: 674 { 675 struct icmp6_hdr *icmp; 676 677 if (offset != 0) /* Type isn't valid */ 678 break; 679 PULLUP_TO(off + 2); 680 icmp = (struct icmp6_hdr *) ((caddr_t)ip6 + off); 681 if (!icmp6type_match(icmp, f)) 682 continue; 683 break; 684 } 685 #undef PULLUP_TO 686 687 bogusfrag: 688 if (fw6_verbose) 689 ip6fw_report(NULL, ip6, rif, oif, off, nxt); 690 goto dropit; 691 } 692 693 got_match: 694 #ifndef IP6FW_DIVERT_RESTART 695 /* Ignore divert/tee rule if socket port is "ignport" */ 696 switch (f->fw_flg & IPV6_FW_F_COMMAND) { 697 case IPV6_FW_F_DIVERT: 698 case IPV6_FW_F_TEE: 699 if (f->fw_divert_port == ignport) 700 continue; /* ignore this rule */ 701 break; 702 } 703 704 #endif /* IP6FW_DIVERT_RESTART */ 705 /* Update statistics */ 706 f->fw_pcnt += 1; 707 f->fw_bcnt += ntohs(ip6->ip6_plen); 708 f->timestamp = time_second; 709 710 /* Log to console if desired */ 711 if ((f->fw_flg & IPV6_FW_F_PRN) && fw6_verbose) 712 ip6fw_report(f, ip6, rif, oif, off, nxt); 713 714 /* Take appropriate action */ 715 switch (f->fw_flg & IPV6_FW_F_COMMAND) { 716 case IPV6_FW_F_ACCEPT: 717 return(0); 718 case IPV6_FW_F_COUNT: 719 continue; 720 case IPV6_FW_F_DIVERT: 721 #ifdef IP6FW_DIVERT_RESTART 722 *cookie = f->fw_number; 723 #else 724 *cookie = htons(f->fw_divert_port); 725 #endif /* IP6FW_DIVERT_RESTART */ 726 return(f->fw_divert_port); 727 case IPV6_FW_F_TEE: 728 /* 729 * XXX someday tee packet here, but beware that you 730 * can't use m_copym() or m_copypacket() because 731 * the divert input routine modifies the mbuf 732 * (and these routines only increment reference 733 * counts in the case of mbuf clusters), so need 734 * to write custom routine. 735 */ 736 continue; 737 case IPV6_FW_F_SKIPTO: 738 #ifdef DIAGNOSTIC 739 while (chain->chain.le_next 740 && chain->chain.le_next->rule->fw_number 741 < f->fw_skipto_rule) 742 #else 743 while (chain->chain.le_next->rule->fw_number 744 < f->fw_skipto_rule) 745 #endif 746 chain = chain->chain.le_next; 747 continue; 748 } 749 750 /* Deny/reject this packet using this rule */ 751 rule = f; 752 break; 753 } 754 755 #ifdef DIAGNOSTIC 756 /* Rule 65535 should always be there and should always match */ 757 if (!chain) 758 panic("ip6_fw: chain"); 759 #endif 760 761 /* 762 * At this point, we're going to drop the packet. 763 * Send a reject notice if all of the following are true: 764 * 765 * - The packet matched a reject rule 766 * - The packet is not an ICMP packet, or is an ICMP query packet 767 * - The packet is not a multicast or broadcast packet 768 */ 769 if ((rule->fw_flg & IPV6_FW_F_COMMAND) == IPV6_FW_F_REJECT 770 && (nxt != IPPROTO_ICMPV6 || is_icmp6_query(ip6, off)) 771 && !((*m)->m_flags & (M_BCAST|M_MCAST)) 772 && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 773 switch (rule->fw_reject_code) { 774 case IPV6_FW_REJECT_RST: 775 { 776 struct tcphdr *const tcp = 777 (struct tcphdr *) ((caddr_t)ip6 + off); 778 struct { 779 struct ip6_hdr ip6; 780 struct tcphdr th; 781 } ti; 782 tcp_seq ack, seq; 783 int flags; 784 785 if (offset != 0 || (tcp->th_flags & TH_RST)) 786 break; 787 788 ti.ip6 = *ip6; 789 ti.th = *tcp; 790 ti.th.th_seq = ntohl(ti.th.th_seq); 791 ti.th.th_ack = ntohl(ti.th.th_ack); 792 ti.ip6.ip6_nxt = IPPROTO_TCP; 793 if (ti.th.th_flags & TH_ACK) { 794 ack = 0; 795 seq = ti.th.th_ack; 796 flags = TH_RST; 797 } else { 798 ack = ti.th.th_seq; 799 if (((*m)->m_flags & M_PKTHDR) != 0) { 800 ack += (*m)->m_pkthdr.len - off 801 - (ti.th.th_off << 2); 802 } else if (ip6->ip6_plen) { 803 ack += ntohs(ip6->ip6_plen) + sizeof(*ip6) 804 - off - (ti.th.th_off << 2); 805 } else { 806 m_freem(*m); 807 *m = 0; 808 break; 809 } 810 seq = 0; 811 flags = TH_RST|TH_ACK; 812 } 813 bcopy(&ti, ip6, sizeof(ti)); 814 tcp_respond(NULL, ip6, (struct tcphdr *)(ip6 + 1), 815 *m, ack, seq, flags); 816 *m = NULL; 817 break; 818 } 819 default: /* Send an ICMP unreachable using code */ 820 if (oif) 821 (*m)->m_pkthdr.rcvif = oif; 822 icmp6_error(*m, ICMP6_DST_UNREACH, 823 rule->fw_reject_code, 0); 824 *m = NULL; 825 break; 826 } 827 } 828 829 dropit: 830 /* 831 * Finally, drop the packet. 832 */ 833 if (*m) { 834 m_freem(*m); 835 *m = NULL; 836 } 837 return(0); 838 } 839 840 static int 841 add_entry6(struct ip6_fw_head *chainptr, struct ip6_fw *frwl) 842 { 843 struct ip6_fw *ftmp = 0; 844 struct ip6_fw_chain *fwc = 0, *fcp, *fcpl = 0; 845 u_short nbr = 0; 846 int s; 847 848 fwc = malloc(sizeof *fwc, M_IP6FW, M_INTWAIT); 849 ftmp = malloc(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 s = splnet(); 858 859 if (!chainptr->lh_first) { 860 LIST_INSERT_HEAD(chainptr, fwc, chain); 861 splx(s); 862 return(0); 863 } else if (ftmp->fw_number == (u_short)-1) { 864 if (fwc) free(fwc, M_IP6FW); 865 if (ftmp) free(ftmp, M_IP6FW); 866 splx(s); 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 splx(s); 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 int s; 907 908 s = splnet(); 909 910 fcp = chainptr->lh_first; 911 if (number != (u_short)-1) { 912 for (; fcp; fcp = fcp->chain.le_next) { 913 if (fcp->rule->fw_number == number) { 914 LIST_REMOVE(fcp, chain); 915 splx(s); 916 free(fcp->rule, M_IP6FW); 917 free(fcp, M_IP6FW); 918 return 0; 919 } 920 } 921 } 922 923 splx(s); 924 return (EINVAL); 925 } 926 927 static int 928 zero_entry6(struct mbuf *m) 929 { 930 struct ip6_fw *frwl; 931 struct ip6_fw_chain *fcp; 932 int s; 933 934 if (m && m->m_len != 0) { 935 if (m->m_len != sizeof(struct ip6_fw)) 936 return(EINVAL); 937 frwl = mtod(m, struct ip6_fw *); 938 } 939 else 940 frwl = NULL; 941 942 /* 943 * It's possible to insert multiple chain entries with the 944 * same number, so we don't stop after finding the first 945 * match if zeroing a specific entry. 946 */ 947 s = splnet(); 948 for (fcp = ip6_fw_chain.lh_first; fcp; fcp = fcp->chain.le_next) 949 if (!frwl || frwl->fw_number == fcp->rule->fw_number) { 950 fcp->rule->fw_bcnt = fcp->rule->fw_pcnt = 0; 951 fcp->rule->timestamp = 0; 952 } 953 splx(s); 954 955 if (fw6_verbose) { 956 if (frwl) 957 log(LOG_SECURITY | LOG_NOTICE, 958 "ip6fw: Entry %d cleared.\n", frwl->fw_number); 959 else 960 log(LOG_SECURITY | LOG_NOTICE, 961 "ip6fw: Accounting cleared.\n"); 962 } 963 964 return(0); 965 } 966 967 static struct ip6_fw * 968 check_ip6fw_mbuf(struct mbuf *m) 969 { 970 /* Check length */ 971 if (m->m_len != sizeof(struct ip6_fw)) { 972 dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len, 973 sizeof(struct ip6_fw))); 974 return (NULL); 975 } 976 return(check_ip6fw_struct(mtod(m, struct ip6_fw *))); 977 } 978 979 static struct ip6_fw * 980 check_ip6fw_struct(struct ip6_fw *frwl) 981 { 982 /* Check for invalid flag bits */ 983 if ((frwl->fw_flg & ~IPV6_FW_F_MASK) != 0) { 984 dprintf(("%s undefined flag bits set (flags=%x)\n", 985 err_prefix, frwl->fw_flg)); 986 return (NULL); 987 } 988 /* Must apply to incoming or outgoing (or both) */ 989 if (!(frwl->fw_flg & (IPV6_FW_F_IN | IPV6_FW_F_OUT))) { 990 dprintf(("%s neither in nor out\n", err_prefix)); 991 return (NULL); 992 } 993 /* Empty interface name is no good */ 994 if (((frwl->fw_flg & IPV6_FW_F_IIFNAME) 995 && !*frwl->fw_in_if.fu_via_if.name) 996 || ((frwl->fw_flg & IPV6_FW_F_OIFNAME) 997 && !*frwl->fw_out_if.fu_via_if.name)) { 998 dprintf(("%s empty interface name\n", err_prefix)); 999 return (NULL); 1000 } 1001 /* Sanity check interface matching */ 1002 if ((frwl->fw_flg & IF6_FW_F_VIAHACK) == IF6_FW_F_VIAHACK) { 1003 ; /* allow "via" backwards compatibility */ 1004 } else if ((frwl->fw_flg & IPV6_FW_F_IN) 1005 && (frwl->fw_flg & IPV6_FW_F_OIFACE)) { 1006 dprintf(("%s outgoing interface check on incoming\n", 1007 err_prefix)); 1008 return (NULL); 1009 } 1010 /* Sanity check port ranges */ 1011 if ((frwl->fw_flg & IPV6_FW_F_SRNG) && IPV6_FW_GETNSRCP(frwl) < 2) { 1012 dprintf(("%s src range set but n_src_p=%d\n", 1013 err_prefix, IPV6_FW_GETNSRCP(frwl))); 1014 return (NULL); 1015 } 1016 if ((frwl->fw_flg & IPV6_FW_F_DRNG) && IPV6_FW_GETNDSTP(frwl) < 2) { 1017 dprintf(("%s dst range set but n_dst_p=%d\n", 1018 err_prefix, IPV6_FW_GETNDSTP(frwl))); 1019 return (NULL); 1020 } 1021 if (IPV6_FW_GETNSRCP(frwl) + IPV6_FW_GETNDSTP(frwl) > IPV6_FW_MAX_PORTS) { 1022 dprintf(("%s too many ports (%d+%d)\n", 1023 err_prefix, IPV6_FW_GETNSRCP(frwl), IPV6_FW_GETNDSTP(frwl))); 1024 return (NULL); 1025 } 1026 /* 1027 * Protocols other than TCP/UDP don't use port range 1028 */ 1029 if ((frwl->fw_prot != IPPROTO_TCP) && 1030 (frwl->fw_prot != IPPROTO_UDP) && 1031 (IPV6_FW_GETNSRCP(frwl) || IPV6_FW_GETNDSTP(frwl))) { 1032 dprintf(("%s port(s) specified for non TCP/UDP rule\n", 1033 err_prefix)); 1034 return(NULL); 1035 } 1036 1037 /* 1038 * Rather than modify the entry to make such entries work, 1039 * we reject this rule and require user level utilities 1040 * to enforce whatever policy they deem appropriate. 1041 */ 1042 if ((frwl->fw_src.s6_addr32[0] & (~frwl->fw_smsk.s6_addr32[0])) || 1043 (frwl->fw_src.s6_addr32[1] & (~frwl->fw_smsk.s6_addr32[1])) || 1044 (frwl->fw_src.s6_addr32[2] & (~frwl->fw_smsk.s6_addr32[2])) || 1045 (frwl->fw_src.s6_addr32[3] & (~frwl->fw_smsk.s6_addr32[3])) || 1046 (frwl->fw_dst.s6_addr32[0] & (~frwl->fw_dmsk.s6_addr32[0])) || 1047 (frwl->fw_dst.s6_addr32[1] & (~frwl->fw_dmsk.s6_addr32[1])) || 1048 (frwl->fw_dst.s6_addr32[2] & (~frwl->fw_dmsk.s6_addr32[2])) || 1049 (frwl->fw_dst.s6_addr32[3] & (~frwl->fw_dmsk.s6_addr32[3]))) { 1050 dprintf(("%s rule never matches\n", err_prefix)); 1051 return(NULL); 1052 } 1053 1054 if ((frwl->fw_flg & IPV6_FW_F_FRAG) && 1055 (frwl->fw_prot == IPPROTO_UDP || frwl->fw_prot == IPPROTO_TCP)) { 1056 if (frwl->fw_nports) { 1057 dprintf(("%s cannot mix 'frag' and ports\n", err_prefix)); 1058 return(NULL); 1059 } 1060 if (frwl->fw_prot == IPPROTO_TCP && 1061 frwl->fw_tcpf != frwl->fw_tcpnf) { 1062 dprintf(("%s cannot mix 'frag' with TCP flags\n", err_prefix)); 1063 return(NULL); 1064 } 1065 } 1066 1067 /* Check command specific stuff */ 1068 switch (frwl->fw_flg & IPV6_FW_F_COMMAND) 1069 { 1070 case IPV6_FW_F_REJECT: 1071 if (frwl->fw_reject_code >= 0x100 1072 && !(frwl->fw_prot == IPPROTO_TCP 1073 && frwl->fw_reject_code == IPV6_FW_REJECT_RST)) { 1074 dprintf(("%s unknown reject code\n", err_prefix)); 1075 return(NULL); 1076 } 1077 break; 1078 case IPV6_FW_F_DIVERT: /* Diverting to port zero is invalid */ 1079 case IPV6_FW_F_TEE: 1080 if (frwl->fw_divert_port == 0) { 1081 dprintf(("%s can't divert to port 0\n", err_prefix)); 1082 return (NULL); 1083 } 1084 break; 1085 case IPV6_FW_F_DENY: 1086 case IPV6_FW_F_ACCEPT: 1087 case IPV6_FW_F_COUNT: 1088 case IPV6_FW_F_SKIPTO: 1089 break; 1090 default: 1091 dprintf(("%s invalid command\n", err_prefix)); 1092 return(NULL); 1093 } 1094 1095 return frwl; 1096 } 1097 1098 static int 1099 ip6_fw_ctl(int stage, struct mbuf **mm) 1100 { 1101 int error; 1102 struct mbuf *m; 1103 1104 if (stage == IPV6_FW_GET) { 1105 struct ip6_fw_chain *fcp = ip6_fw_chain.lh_first; 1106 *mm = m = m_get(MB_WAIT, MT_DATA); /* XXX */ 1107 if (!m) 1108 return(ENOBUFS); 1109 if (sizeof *(fcp->rule) > MLEN) { 1110 MCLGET(m, MB_WAIT); 1111 if ((m->m_flags & M_EXT) == 0) { 1112 m_free(m); 1113 return(ENOBUFS); 1114 } 1115 } 1116 for (; fcp; fcp = fcp->chain.le_next) { 1117 bcopy(fcp->rule, m->m_data, sizeof *(fcp->rule)); 1118 m->m_len = sizeof *(fcp->rule); 1119 m->m_next = m_get(MB_WAIT, MT_DATA); /* XXX */ 1120 if (!m->m_next) { 1121 m_freem(*mm); 1122 return(ENOBUFS); 1123 } 1124 m = m->m_next; 1125 if (sizeof *(fcp->rule) > MLEN) { 1126 MCLGET(m, MB_WAIT); 1127 if ((m->m_flags & M_EXT) == 0) { 1128 m_freem(*mm); 1129 return(ENOBUFS); 1130 } 1131 } 1132 m->m_len = 0; 1133 } 1134 return (0); 1135 } 1136 m = *mm; 1137 /* only allow get calls if secure mode > 2 */ 1138 if (securelevel > 2) { 1139 if (m) { 1140 (void)m_freem(m); 1141 *mm = 0; 1142 } 1143 return(EPERM); 1144 } 1145 if (stage == IPV6_FW_FLUSH) { 1146 while (ip6_fw_chain.lh_first != NULL && 1147 ip6_fw_chain.lh_first->rule->fw_number != (u_short)-1) { 1148 struct ip6_fw_chain *fcp = ip6_fw_chain.lh_first; 1149 int s = splnet(); 1150 LIST_REMOVE(ip6_fw_chain.lh_first, chain); 1151 splx(s); 1152 free(fcp->rule, M_IP6FW); 1153 free(fcp, M_IP6FW); 1154 } 1155 if (m) { 1156 (void)m_freem(m); 1157 *mm = 0; 1158 } 1159 return (0); 1160 } 1161 if (stage == IPV6_FW_ZERO) { 1162 error = zero_entry6(m); 1163 if (m) { 1164 (void)m_freem(m); 1165 *mm = 0; 1166 } 1167 return (error); 1168 } 1169 if (m == NULL) { 1170 printf("%s NULL mbuf ptr\n", err_prefix); 1171 return (EINVAL); 1172 } 1173 1174 if (stage == IPV6_FW_ADD) { 1175 struct ip6_fw *frwl = check_ip6fw_mbuf(m); 1176 1177 if (!frwl) 1178 error = EINVAL; 1179 else 1180 error = add_entry6(&ip6_fw_chain, frwl); 1181 if (m) { 1182 (void)m_freem(m); 1183 *mm = 0; 1184 } 1185 return error; 1186 } 1187 if (stage == IPV6_FW_DEL) { 1188 if (m->m_len != sizeof(struct ip6_fw)) { 1189 dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len, 1190 sizeof(struct ip6_fw))); 1191 error = EINVAL; 1192 } else if (mtod(m, struct ip6_fw *)->fw_number == (u_short)-1) { 1193 dprintf(("%s can't delete rule 65535\n", err_prefix)); 1194 error = EINVAL; 1195 } else 1196 error = del_entry6(&ip6_fw_chain, 1197 mtod(m, struct ip6_fw *)->fw_number); 1198 if (m) { 1199 (void)m_freem(m); 1200 *mm = 0; 1201 } 1202 return error; 1203 } 1204 1205 dprintf(("%s unknown request %d\n", err_prefix, stage)); 1206 if (m) { 1207 (void)m_freem(m); 1208 *mm = 0; 1209 } 1210 return (EINVAL); 1211 } 1212 1213 void 1214 ip6_fw_init(void) 1215 { 1216 struct ip6_fw default_rule; 1217 1218 ip6_fw_chk_ptr = ip6_fw_chk; 1219 ip6_fw_ctl_ptr = ip6_fw_ctl; 1220 LIST_INIT(&ip6_fw_chain); 1221 1222 bzero(&default_rule, sizeof default_rule); 1223 default_rule.fw_prot = IPPROTO_IPV6; 1224 default_rule.fw_number = (u_short)-1; 1225 #ifdef IPV6FIREWALL_DEFAULT_TO_ACCEPT 1226 default_rule.fw_flg |= IPV6_FW_F_ACCEPT; 1227 #else 1228 default_rule.fw_flg |= IPV6_FW_F_DENY; 1229 #endif 1230 default_rule.fw_flg |= IPV6_FW_F_IN | IPV6_FW_F_OUT; 1231 if (check_ip6fw_struct(&default_rule) == NULL || 1232 add_entry6(&ip6_fw_chain, &default_rule)) 1233 panic(__FUNCTION__); 1234 1235 printf("IPv6 packet filtering initialized, "); 1236 #ifdef IPV6FIREWALL_DEFAULT_TO_ACCEPT 1237 printf("default to accept, "); 1238 #endif 1239 #ifndef IPV6FIREWALL_VERBOSE 1240 printf("logging disabled\n"); 1241 #else 1242 if (fw6_verbose_limit == 0) 1243 printf("unlimited logging\n"); 1244 else 1245 printf("logging limited to %d packets/entry\n", 1246 fw6_verbose_limit); 1247 #endif 1248 } 1249 1250 static ip6_fw_chk_t *old_chk_ptr; 1251 static ip6_fw_ctl_t *old_ctl_ptr; 1252 1253 static int 1254 ip6fw_modevent(module_t mod, int type, void *unused) 1255 { 1256 int s; 1257 1258 switch (type) { 1259 case MOD_LOAD: 1260 s = splnet(); 1261 1262 old_chk_ptr = ip6_fw_chk_ptr; 1263 old_ctl_ptr = ip6_fw_ctl_ptr; 1264 1265 ip6_fw_init(); 1266 splx(s); 1267 return 0; 1268 case MOD_UNLOAD: 1269 s = splnet(); 1270 ip6_fw_chk_ptr = old_chk_ptr; 1271 ip6_fw_ctl_ptr = old_ctl_ptr; 1272 while (LIST_FIRST(&ip6_fw_chain) != NULL) { 1273 struct ip6_fw_chain *fcp = LIST_FIRST(&ip6_fw_chain); 1274 LIST_REMOVE(LIST_FIRST(&ip6_fw_chain), chain); 1275 free(fcp->rule, M_IP6FW); 1276 free(fcp, M_IP6FW); 1277 } 1278 1279 splx(s); 1280 printf("IPv6 firewall unloaded\n"); 1281 return 0; 1282 default: 1283 break; 1284 } 1285 return 0; 1286 } 1287 1288 static moduledata_t ip6fwmod = { 1289 "ip6fw", 1290 ip6fw_modevent, 1291 0 1292 }; 1293 DECLARE_MODULE(ip6fw, ip6fwmod, SI_SUB_PSEUDO, SI_ORDER_ANY); 1294