ip_fw2.c revision 227232
1/*- 2 * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26#include <sys/cdefs.h> 27__FBSDID("$FreeBSD: stable/9/sys/netinet/ipfw/ip_fw2.c 227232 2011-11-06 17:31:57Z bz $"); 28 29/* 30 * The FreeBSD IP packet firewall, main file 31 */ 32 33#include "opt_ipfw.h" 34#include "opt_ipdivert.h" 35#include "opt_inet.h" 36#ifndef INET 37#error IPFIREWALL requires INET. 38#endif /* INET */ 39#include "opt_inet6.h" 40#include "opt_ipsec.h" 41 42#include <sys/param.h> 43#include <sys/systm.h> 44#include <sys/condvar.h> 45#include <sys/eventhandler.h> 46#include <sys/malloc.h> 47#include <sys/mbuf.h> 48#include <sys/kernel.h> 49#include <sys/lock.h> 50#include <sys/jail.h> 51#include <sys/module.h> 52#include <sys/priv.h> 53#include <sys/proc.h> 54#include <sys/rwlock.h> 55#include <sys/socket.h> 56#include <sys/socketvar.h> 57#include <sys/sysctl.h> 58#include <sys/syslog.h> 59#include <sys/ucred.h> 60#include <net/ethernet.h> /* for ETHERTYPE_IP */ 61#include <net/if.h> 62#include <net/route.h> 63#include <net/pf_mtag.h> 64#include <net/vnet.h> 65 66#include <netinet/in.h> 67#include <netinet/in_var.h> 68#include <netinet/in_pcb.h> 69#include <netinet/ip.h> 70#include <netinet/ip_var.h> 71#include <netinet/ip_icmp.h> 72#include <netinet/ip_fw.h> 73#include <netinet/ipfw/ip_fw_private.h> 74#include <netinet/ip_carp.h> 75#include <netinet/pim.h> 76#include <netinet/tcp_var.h> 77#include <netinet/udp.h> 78#include <netinet/udp_var.h> 79#include <netinet/sctp.h> 80 81#include <netinet/ip6.h> 82#include <netinet/icmp6.h> 83#ifdef INET6 84#include <netinet6/in6_pcb.h> 85#include <netinet6/scope6_var.h> 86#include <netinet6/ip6_var.h> 87#endif 88 89#include <machine/in_cksum.h> /* XXX for in_cksum */ 90 91#ifdef MAC 92#include <security/mac/mac_framework.h> 93#endif 94 95/* 96 * static variables followed by global ones. 97 * All ipfw global variables are here. 98 */ 99 100/* ipfw_vnet_ready controls when we are open for business */ 101static VNET_DEFINE(int, ipfw_vnet_ready) = 0; 102#define V_ipfw_vnet_ready VNET(ipfw_vnet_ready) 103 104static VNET_DEFINE(int, fw_deny_unknown_exthdrs); 105#define V_fw_deny_unknown_exthdrs VNET(fw_deny_unknown_exthdrs) 106 107static VNET_DEFINE(int, fw_permit_single_frag6) = 1; 108#define V_fw_permit_single_frag6 VNET(fw_permit_single_frag6) 109 110#ifdef IPFIREWALL_DEFAULT_TO_ACCEPT 111static int default_to_accept = 1; 112#else 113static int default_to_accept; 114#endif 115 116VNET_DEFINE(int, autoinc_step); 117VNET_DEFINE(int, fw_one_pass) = 1; 118 119/* 120 * Each rule belongs to one of 32 different sets (0..31). 121 * The variable set_disable contains one bit per set. 122 * If the bit is set, all rules in the corresponding set 123 * are disabled. Set RESVD_SET(31) is reserved for the default rule 124 * and rules that are not deleted by the flush command, 125 * and CANNOT be disabled. 126 * Rules in set RESVD_SET can only be deleted individually. 127 */ 128VNET_DEFINE(u_int32_t, set_disable); 129#define V_set_disable VNET(set_disable) 130 131VNET_DEFINE(int, fw_verbose); 132/* counter for ipfw_log(NULL...) */ 133VNET_DEFINE(u_int64_t, norule_counter); 134VNET_DEFINE(int, verbose_limit); 135 136/* layer3_chain contains the list of rules for layer 3 */ 137VNET_DEFINE(struct ip_fw_chain, layer3_chain); 138 139ipfw_nat_t *ipfw_nat_ptr = NULL; 140struct cfg_nat *(*lookup_nat_ptr)(struct nat_list *, int); 141ipfw_nat_cfg_t *ipfw_nat_cfg_ptr; 142ipfw_nat_cfg_t *ipfw_nat_del_ptr; 143ipfw_nat_cfg_t *ipfw_nat_get_cfg_ptr; 144ipfw_nat_cfg_t *ipfw_nat_get_log_ptr; 145 146#ifdef SYSCTL_NODE 147uint32_t dummy_def = IPFW_DEFAULT_RULE; 148uint32_t dummy_tables_max = IPFW_TABLES_MAX; 149 150SYSBEGIN(f3) 151 152SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall"); 153SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, one_pass, 154 CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_one_pass), 0, 155 "Only do a single pass through ipfw when using dummynet(4)"); 156SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, autoinc_step, 157 CTLFLAG_RW, &VNET_NAME(autoinc_step), 0, 158 "Rule number auto-increment step"); 159SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, verbose, 160 CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_verbose), 0, 161 "Log matches to ipfw rules"); 162SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit, 163 CTLFLAG_RW, &VNET_NAME(verbose_limit), 0, 164 "Set upper limit of matches of ipfw rules logged"); 165SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, default_rule, CTLFLAG_RD, 166 &dummy_def, 0, 167 "The default/max possible rule number."); 168SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, tables_max, CTLFLAG_RD, 169 &dummy_tables_max, 0, 170 "The maximum number of tables."); 171SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, default_to_accept, CTLFLAG_RDTUN, 172 &default_to_accept, 0, 173 "Make the default rule accept all packets."); 174TUNABLE_INT("net.inet.ip.fw.default_to_accept", &default_to_accept); 175SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, static_count, 176 CTLFLAG_RD, &VNET_NAME(layer3_chain.n_rules), 0, 177 "Number of static rules"); 178 179#ifdef INET6 180SYSCTL_DECL(_net_inet6_ip6); 181SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall"); 182SYSCTL_VNET_INT(_net_inet6_ip6_fw, OID_AUTO, deny_unknown_exthdrs, 183 CTLFLAG_RW | CTLFLAG_SECURE, &VNET_NAME(fw_deny_unknown_exthdrs), 0, 184 "Deny packets with unknown IPv6 Extension Headers"); 185SYSCTL_VNET_INT(_net_inet6_ip6_fw, OID_AUTO, permit_single_frag6, 186 CTLFLAG_RW | CTLFLAG_SECURE, &VNET_NAME(fw_permit_single_frag6), 0, 187 "Permit single packet IPv6 fragments"); 188#endif /* INET6 */ 189 190SYSEND 191 192#endif /* SYSCTL_NODE */ 193 194 195/* 196 * Some macros used in the various matching options. 197 * L3HDR maps an ipv4 pointer into a layer3 header pointer of type T 198 * Other macros just cast void * into the appropriate type 199 */ 200#define L3HDR(T, ip) ((T *)((u_int32_t *)(ip) + (ip)->ip_hl)) 201#define TCP(p) ((struct tcphdr *)(p)) 202#define SCTP(p) ((struct sctphdr *)(p)) 203#define UDP(p) ((struct udphdr *)(p)) 204#define ICMP(p) ((struct icmphdr *)(p)) 205#define ICMP6(p) ((struct icmp6_hdr *)(p)) 206 207static __inline int 208icmptype_match(struct icmphdr *icmp, ipfw_insn_u32 *cmd) 209{ 210 int type = icmp->icmp_type; 211 212 return (type <= ICMP_MAXTYPE && (cmd->d[0] & (1<<type)) ); 213} 214 215#define TT ( (1 << ICMP_ECHO) | (1 << ICMP_ROUTERSOLICIT) | \ 216 (1 << ICMP_TSTAMP) | (1 << ICMP_IREQ) | (1 << ICMP_MASKREQ) ) 217 218static int 219is_icmp_query(struct icmphdr *icmp) 220{ 221 int type = icmp->icmp_type; 222 223 return (type <= ICMP_MAXTYPE && (TT & (1<<type)) ); 224} 225#undef TT 226 227/* 228 * The following checks use two arrays of 8 or 16 bits to store the 229 * bits that we want set or clear, respectively. They are in the 230 * low and high half of cmd->arg1 or cmd->d[0]. 231 * 232 * We scan options and store the bits we find set. We succeed if 233 * 234 * (want_set & ~bits) == 0 && (want_clear & ~bits) == want_clear 235 * 236 * The code is sometimes optimized not to store additional variables. 237 */ 238 239static int 240flags_match(ipfw_insn *cmd, u_int8_t bits) 241{ 242 u_char want_clear; 243 bits = ~bits; 244 245 if ( ((cmd->arg1 & 0xff) & bits) != 0) 246 return 0; /* some bits we want set were clear */ 247 want_clear = (cmd->arg1 >> 8) & 0xff; 248 if ( (want_clear & bits) != want_clear) 249 return 0; /* some bits we want clear were set */ 250 return 1; 251} 252 253static int 254ipopts_match(struct ip *ip, ipfw_insn *cmd) 255{ 256 int optlen, bits = 0; 257 u_char *cp = (u_char *)(ip + 1); 258 int x = (ip->ip_hl << 2) - sizeof (struct ip); 259 260 for (; x > 0; x -= optlen, cp += optlen) { 261 int opt = cp[IPOPT_OPTVAL]; 262 263 if (opt == IPOPT_EOL) 264 break; 265 if (opt == IPOPT_NOP) 266 optlen = 1; 267 else { 268 optlen = cp[IPOPT_OLEN]; 269 if (optlen <= 0 || optlen > x) 270 return 0; /* invalid or truncated */ 271 } 272 switch (opt) { 273 274 default: 275 break; 276 277 case IPOPT_LSRR: 278 bits |= IP_FW_IPOPT_LSRR; 279 break; 280 281 case IPOPT_SSRR: 282 bits |= IP_FW_IPOPT_SSRR; 283 break; 284 285 case IPOPT_RR: 286 bits |= IP_FW_IPOPT_RR; 287 break; 288 289 case IPOPT_TS: 290 bits |= IP_FW_IPOPT_TS; 291 break; 292 } 293 } 294 return (flags_match(cmd, bits)); 295} 296 297static int 298tcpopts_match(struct tcphdr *tcp, ipfw_insn *cmd) 299{ 300 int optlen, bits = 0; 301 u_char *cp = (u_char *)(tcp + 1); 302 int x = (tcp->th_off << 2) - sizeof(struct tcphdr); 303 304 for (; x > 0; x -= optlen, cp += optlen) { 305 int opt = cp[0]; 306 if (opt == TCPOPT_EOL) 307 break; 308 if (opt == TCPOPT_NOP) 309 optlen = 1; 310 else { 311 optlen = cp[1]; 312 if (optlen <= 0) 313 break; 314 } 315 316 switch (opt) { 317 318 default: 319 break; 320 321 case TCPOPT_MAXSEG: 322 bits |= IP_FW_TCPOPT_MSS; 323 break; 324 325 case TCPOPT_WINDOW: 326 bits |= IP_FW_TCPOPT_WINDOW; 327 break; 328 329 case TCPOPT_SACK_PERMITTED: 330 case TCPOPT_SACK: 331 bits |= IP_FW_TCPOPT_SACK; 332 break; 333 334 case TCPOPT_TIMESTAMP: 335 bits |= IP_FW_TCPOPT_TS; 336 break; 337 338 } 339 } 340 return (flags_match(cmd, bits)); 341} 342 343static int 344iface_match(struct ifnet *ifp, ipfw_insn_if *cmd) 345{ 346 if (ifp == NULL) /* no iface with this packet, match fails */ 347 return 0; 348 /* Check by name or by IP address */ 349 if (cmd->name[0] != '\0') { /* match by name */ 350 /* Check name */ 351 if (cmd->p.glob) { 352 if (fnmatch(cmd->name, ifp->if_xname, 0) == 0) 353 return(1); 354 } else { 355 if (strncmp(ifp->if_xname, cmd->name, IFNAMSIZ) == 0) 356 return(1); 357 } 358 } else { 359#ifdef __FreeBSD__ /* and OSX too ? */ 360 struct ifaddr *ia; 361 362 if_addr_rlock(ifp); 363 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 364 if (ia->ifa_addr->sa_family != AF_INET) 365 continue; 366 if (cmd->p.ip.s_addr == ((struct sockaddr_in *) 367 (ia->ifa_addr))->sin_addr.s_addr) { 368 if_addr_runlock(ifp); 369 return(1); /* match */ 370 } 371 } 372 if_addr_runlock(ifp); 373#endif /* __FreeBSD__ */ 374 } 375 return(0); /* no match, fail ... */ 376} 377 378/* 379 * The verify_path function checks if a route to the src exists and 380 * if it is reachable via ifp (when provided). 381 * 382 * The 'verrevpath' option checks that the interface that an IP packet 383 * arrives on is the same interface that traffic destined for the 384 * packet's source address would be routed out of. 385 * The 'versrcreach' option just checks that the source address is 386 * reachable via any route (except default) in the routing table. 387 * These two are a measure to block forged packets. This is also 388 * commonly known as "anti-spoofing" or Unicast Reverse Path 389 * Forwarding (Unicast RFP) in Cisco-ese. The name of the knobs 390 * is purposely reminiscent of the Cisco IOS command, 391 * 392 * ip verify unicast reverse-path 393 * ip verify unicast source reachable-via any 394 * 395 * which implements the same functionality. But note that the syntax 396 * is misleading, and the check may be performed on all IP packets 397 * whether unicast, multicast, or broadcast. 398 */ 399static int 400verify_path(struct in_addr src, struct ifnet *ifp, u_int fib) 401{ 402#ifndef __FreeBSD__ 403 return 0; 404#else 405 struct route ro; 406 struct sockaddr_in *dst; 407 408 bzero(&ro, sizeof(ro)); 409 410 dst = (struct sockaddr_in *)&(ro.ro_dst); 411 dst->sin_family = AF_INET; 412 dst->sin_len = sizeof(*dst); 413 dst->sin_addr = src; 414 in_rtalloc_ign(&ro, 0, fib); 415 416 if (ro.ro_rt == NULL) 417 return 0; 418 419 /* 420 * If ifp is provided, check for equality with rtentry. 421 * We should use rt->rt_ifa->ifa_ifp, instead of rt->rt_ifp, 422 * in order to pass packets injected back by if_simloop(): 423 * if useloopback == 1 routing entry (via lo0) for our own address 424 * may exist, so we need to handle routing assymetry. 425 */ 426 if (ifp != NULL && ro.ro_rt->rt_ifa->ifa_ifp != ifp) { 427 RTFREE(ro.ro_rt); 428 return 0; 429 } 430 431 /* if no ifp provided, check if rtentry is not default route */ 432 if (ifp == NULL && 433 satosin(rt_key(ro.ro_rt))->sin_addr.s_addr == INADDR_ANY) { 434 RTFREE(ro.ro_rt); 435 return 0; 436 } 437 438 /* or if this is a blackhole/reject route */ 439 if (ifp == NULL && ro.ro_rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 440 RTFREE(ro.ro_rt); 441 return 0; 442 } 443 444 /* found valid route */ 445 RTFREE(ro.ro_rt); 446 return 1; 447#endif /* __FreeBSD__ */ 448} 449 450#ifdef INET6 451/* 452 * ipv6 specific rules here... 453 */ 454static __inline int 455icmp6type_match (int type, ipfw_insn_u32 *cmd) 456{ 457 return (type <= ICMP6_MAXTYPE && (cmd->d[type/32] & (1<<(type%32)) ) ); 458} 459 460static int 461flow6id_match( int curr_flow, ipfw_insn_u32 *cmd ) 462{ 463 int i; 464 for (i=0; i <= cmd->o.arg1; ++i ) 465 if (curr_flow == cmd->d[i] ) 466 return 1; 467 return 0; 468} 469 470/* support for IP6_*_ME opcodes */ 471static int 472search_ip6_addr_net (struct in6_addr * ip6_addr) 473{ 474 struct ifnet *mdc; 475 struct ifaddr *mdc2; 476 struct in6_ifaddr *fdm; 477 struct in6_addr copia; 478 479 TAILQ_FOREACH(mdc, &V_ifnet, if_link) { 480 if_addr_rlock(mdc); 481 TAILQ_FOREACH(mdc2, &mdc->if_addrhead, ifa_link) { 482 if (mdc2->ifa_addr->sa_family == AF_INET6) { 483 fdm = (struct in6_ifaddr *)mdc2; 484 copia = fdm->ia_addr.sin6_addr; 485 /* need for leaving scope_id in the sock_addr */ 486 in6_clearscope(&copia); 487 if (IN6_ARE_ADDR_EQUAL(ip6_addr, &copia)) { 488 if_addr_runlock(mdc); 489 return 1; 490 } 491 } 492 } 493 if_addr_runlock(mdc); 494 } 495 return 0; 496} 497 498static int 499verify_path6(struct in6_addr *src, struct ifnet *ifp) 500{ 501 struct route_in6 ro; 502 struct sockaddr_in6 *dst; 503 504 bzero(&ro, sizeof(ro)); 505 506 dst = (struct sockaddr_in6 * )&(ro.ro_dst); 507 dst->sin6_family = AF_INET6; 508 dst->sin6_len = sizeof(*dst); 509 dst->sin6_addr = *src; 510 /* XXX MRT 0 for ipv6 at this time */ 511 rtalloc_ign((struct route *)&ro, 0); 512 513 if (ro.ro_rt == NULL) 514 return 0; 515 516 /* 517 * if ifp is provided, check for equality with rtentry 518 * We should use rt->rt_ifa->ifa_ifp, instead of rt->rt_ifp, 519 * to support the case of sending packets to an address of our own. 520 * (where the former interface is the first argument of if_simloop() 521 * (=ifp), the latter is lo0) 522 */ 523 if (ifp != NULL && ro.ro_rt->rt_ifa->ifa_ifp != ifp) { 524 RTFREE(ro.ro_rt); 525 return 0; 526 } 527 528 /* if no ifp provided, check if rtentry is not default route */ 529 if (ifp == NULL && 530 IN6_IS_ADDR_UNSPECIFIED(&satosin6(rt_key(ro.ro_rt))->sin6_addr)) { 531 RTFREE(ro.ro_rt); 532 return 0; 533 } 534 535 /* or if this is a blackhole/reject route */ 536 if (ifp == NULL && ro.ro_rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 537 RTFREE(ro.ro_rt); 538 return 0; 539 } 540 541 /* found valid route */ 542 RTFREE(ro.ro_rt); 543 return 1; 544 545} 546 547static int 548is_icmp6_query(int icmp6_type) 549{ 550 if ((icmp6_type <= ICMP6_MAXTYPE) && 551 (icmp6_type == ICMP6_ECHO_REQUEST || 552 icmp6_type == ICMP6_MEMBERSHIP_QUERY || 553 icmp6_type == ICMP6_WRUREQUEST || 554 icmp6_type == ICMP6_FQDN_QUERY || 555 icmp6_type == ICMP6_NI_QUERY)) 556 return (1); 557 558 return (0); 559} 560 561static void 562send_reject6(struct ip_fw_args *args, int code, u_int hlen, struct ip6_hdr *ip6) 563{ 564 struct mbuf *m; 565 566 m = args->m; 567 if (code == ICMP6_UNREACH_RST && args->f_id.proto == IPPROTO_TCP) { 568 struct tcphdr *tcp; 569 tcp = (struct tcphdr *)((char *)ip6 + hlen); 570 571 if ((tcp->th_flags & TH_RST) == 0) { 572 struct mbuf *m0; 573 m0 = ipfw_send_pkt(args->m, &(args->f_id), 574 ntohl(tcp->th_seq), ntohl(tcp->th_ack), 575 tcp->th_flags | TH_RST); 576 if (m0 != NULL) 577 ip6_output(m0, NULL, NULL, 0, NULL, NULL, 578 NULL); 579 } 580 FREE_PKT(m); 581 } else if (code != ICMP6_UNREACH_RST) { /* Send an ICMPv6 unreach. */ 582#if 0 583 /* 584 * Unlike above, the mbufs need to line up with the ip6 hdr, 585 * as the contents are read. We need to m_adj() the 586 * needed amount. 587 * The mbuf will however be thrown away so we can adjust it. 588 * Remember we did an m_pullup on it already so we 589 * can make some assumptions about contiguousness. 590 */ 591 if (args->L3offset) 592 m_adj(m, args->L3offset); 593#endif 594 icmp6_error(m, ICMP6_DST_UNREACH, code, 0); 595 } else 596 FREE_PKT(m); 597 598 args->m = NULL; 599} 600 601#endif /* INET6 */ 602 603 604/* 605 * sends a reject message, consuming the mbuf passed as an argument. 606 */ 607static void 608send_reject(struct ip_fw_args *args, int code, int iplen, struct ip *ip) 609{ 610 611#if 0 612 /* XXX When ip is not guaranteed to be at mtod() we will 613 * need to account for this */ 614 * The mbuf will however be thrown away so we can adjust it. 615 * Remember we did an m_pullup on it already so we 616 * can make some assumptions about contiguousness. 617 */ 618 if (args->L3offset) 619 m_adj(m, args->L3offset); 620#endif 621 if (code != ICMP_REJECT_RST) { /* Send an ICMP unreach */ 622 /* We need the IP header in host order for icmp_error(). */ 623 SET_HOST_IPLEN(ip); 624 icmp_error(args->m, ICMP_UNREACH, code, 0L, 0); 625 } else if (args->f_id.proto == IPPROTO_TCP) { 626 struct tcphdr *const tcp = 627 L3HDR(struct tcphdr, mtod(args->m, struct ip *)); 628 if ( (tcp->th_flags & TH_RST) == 0) { 629 struct mbuf *m; 630 m = ipfw_send_pkt(args->m, &(args->f_id), 631 ntohl(tcp->th_seq), ntohl(tcp->th_ack), 632 tcp->th_flags | TH_RST); 633 if (m != NULL) 634 ip_output(m, NULL, NULL, 0, NULL, NULL); 635 } 636 FREE_PKT(args->m); 637 } else 638 FREE_PKT(args->m); 639 args->m = NULL; 640} 641 642/* 643 * Support for uid/gid/jail lookup. These tests are expensive 644 * (because we may need to look into the list of active sockets) 645 * so we cache the results. ugid_lookupp is 0 if we have not 646 * yet done a lookup, 1 if we succeeded, and -1 if we tried 647 * and failed. The function always returns the match value. 648 * We could actually spare the variable and use *uc, setting 649 * it to '(void *)check_uidgid if we have no info, NULL if 650 * we tried and failed, or any other value if successful. 651 */ 652static int 653check_uidgid(ipfw_insn_u32 *insn, struct ip_fw_args *args, int *ugid_lookupp, 654 struct ucred **uc) 655{ 656#ifndef __FreeBSD__ 657 /* XXX */ 658 return cred_check(insn, proto, oif, 659 dst_ip, dst_port, src_ip, src_port, 660 (struct bsd_ucred *)uc, ugid_lookupp, ((struct mbuf *)inp)->m_skb); 661#else /* FreeBSD */ 662 struct in_addr src_ip, dst_ip; 663 struct inpcbinfo *pi; 664 struct ipfw_flow_id *id; 665 struct inpcb *pcb, *inp; 666 struct ifnet *oif; 667 int lookupflags; 668 int match; 669 670 id = &args->f_id; 671 inp = args->inp; 672 oif = args->oif; 673 674 /* 675 * Check to see if the UDP or TCP stack supplied us with 676 * the PCB. If so, rather then holding a lock and looking 677 * up the PCB, we can use the one that was supplied. 678 */ 679 if (inp && *ugid_lookupp == 0) { 680 INP_LOCK_ASSERT(inp); 681 if (inp->inp_socket != NULL) { 682 *uc = crhold(inp->inp_cred); 683 *ugid_lookupp = 1; 684 } else 685 *ugid_lookupp = -1; 686 } 687 /* 688 * If we have already been here and the packet has no 689 * PCB entry associated with it, then we can safely 690 * assume that this is a no match. 691 */ 692 if (*ugid_lookupp == -1) 693 return (0); 694 if (id->proto == IPPROTO_TCP) { 695 lookupflags = 0; 696 pi = &V_tcbinfo; 697 } else if (id->proto == IPPROTO_UDP) { 698 lookupflags = INPLOOKUP_WILDCARD; 699 pi = &V_udbinfo; 700 } else 701 return 0; 702 lookupflags |= INPLOOKUP_RLOCKPCB; 703 match = 0; 704 if (*ugid_lookupp == 0) { 705 if (id->addr_type == 6) { 706#ifdef INET6 707 if (oif == NULL) 708 pcb = in6_pcblookup_mbuf(pi, 709 &id->src_ip6, htons(id->src_port), 710 &id->dst_ip6, htons(id->dst_port), 711 lookupflags, oif, args->m); 712 else 713 pcb = in6_pcblookup_mbuf(pi, 714 &id->dst_ip6, htons(id->dst_port), 715 &id->src_ip6, htons(id->src_port), 716 lookupflags, oif, args->m); 717#else 718 *ugid_lookupp = -1; 719 return (0); 720#endif 721 } else { 722 src_ip.s_addr = htonl(id->src_ip); 723 dst_ip.s_addr = htonl(id->dst_ip); 724 if (oif == NULL) 725 pcb = in_pcblookup_mbuf(pi, 726 src_ip, htons(id->src_port), 727 dst_ip, htons(id->dst_port), 728 lookupflags, oif, args->m); 729 else 730 pcb = in_pcblookup_mbuf(pi, 731 dst_ip, htons(id->dst_port), 732 src_ip, htons(id->src_port), 733 lookupflags, oif, args->m); 734 } 735 if (pcb != NULL) { 736 INP_RLOCK_ASSERT(pcb); 737 *uc = crhold(pcb->inp_cred); 738 *ugid_lookupp = 1; 739 INP_RUNLOCK(pcb); 740 } 741 if (*ugid_lookupp == 0) { 742 /* 743 * We tried and failed, set the variable to -1 744 * so we will not try again on this packet. 745 */ 746 *ugid_lookupp = -1; 747 return (0); 748 } 749 } 750 if (insn->o.opcode == O_UID) 751 match = ((*uc)->cr_uid == (uid_t)insn->d[0]); 752 else if (insn->o.opcode == O_GID) 753 match = groupmember((gid_t)insn->d[0], *uc); 754 else if (insn->o.opcode == O_JAIL) 755 match = ((*uc)->cr_prison->pr_id == (int)insn->d[0]); 756 return (match); 757#endif /* __FreeBSD__ */ 758} 759 760/* 761 * Helper function to set args with info on the rule after the matching 762 * one. slot is precise, whereas we guess rule_id as they are 763 * assigned sequentially. 764 */ 765static inline void 766set_match(struct ip_fw_args *args, int slot, 767 struct ip_fw_chain *chain) 768{ 769 args->rule.chain_id = chain->id; 770 args->rule.slot = slot + 1; /* we use 0 as a marker */ 771 args->rule.rule_id = 1 + chain->map[slot]->id; 772 args->rule.rulenum = chain->map[slot]->rulenum; 773} 774 775/* 776 * The main check routine for the firewall. 777 * 778 * All arguments are in args so we can modify them and return them 779 * back to the caller. 780 * 781 * Parameters: 782 * 783 * args->m (in/out) The packet; we set to NULL when/if we nuke it. 784 * Starts with the IP header. 785 * args->eh (in) Mac header if present, NULL for layer3 packet. 786 * args->L3offset Number of bytes bypassed if we came from L2. 787 * e.g. often sizeof(eh) ** NOTYET ** 788 * args->oif Outgoing interface, NULL if packet is incoming. 789 * The incoming interface is in the mbuf. (in) 790 * args->divert_rule (in/out) 791 * Skip up to the first rule past this rule number; 792 * upon return, non-zero port number for divert or tee. 793 * 794 * args->rule Pointer to the last matching rule (in/out) 795 * args->next_hop Socket we are forwarding to (out). 796 * args->next_hop6 IPv6 next hop we are forwarding to (out). 797 * args->f_id Addresses grabbed from the packet (out) 798 * args->rule.info a cookie depending on rule action 799 * 800 * Return value: 801 * 802 * IP_FW_PASS the packet must be accepted 803 * IP_FW_DENY the packet must be dropped 804 * IP_FW_DIVERT divert packet, port in m_tag 805 * IP_FW_TEE tee packet, port in m_tag 806 * IP_FW_DUMMYNET to dummynet, pipe in args->cookie 807 * IP_FW_NETGRAPH into netgraph, cookie args->cookie 808 * args->rule contains the matching rule, 809 * args->rule.info has additional information. 810 * 811 */ 812int 813ipfw_chk(struct ip_fw_args *args) 814{ 815 816 /* 817 * Local variables holding state while processing a packet: 818 * 819 * IMPORTANT NOTE: to speed up the processing of rules, there 820 * are some assumption on the values of the variables, which 821 * are documented here. Should you change them, please check 822 * the implementation of the various instructions to make sure 823 * that they still work. 824 * 825 * args->eh The MAC header. It is non-null for a layer2 826 * packet, it is NULL for a layer-3 packet. 827 * **notyet** 828 * args->L3offset Offset in the packet to the L3 (IP or equiv.) header. 829 * 830 * m | args->m Pointer to the mbuf, as received from the caller. 831 * It may change if ipfw_chk() does an m_pullup, or if it 832 * consumes the packet because it calls send_reject(). 833 * XXX This has to change, so that ipfw_chk() never modifies 834 * or consumes the buffer. 835 * ip is the beginning of the ip(4 or 6) header. 836 * Calculated by adding the L3offset to the start of data. 837 * (Until we start using L3offset, the packet is 838 * supposed to start with the ip header). 839 */ 840 struct mbuf *m = args->m; 841 struct ip *ip = mtod(m, struct ip *); 842 843 /* 844 * For rules which contain uid/gid or jail constraints, cache 845 * a copy of the users credentials after the pcb lookup has been 846 * executed. This will speed up the processing of rules with 847 * these types of constraints, as well as decrease contention 848 * on pcb related locks. 849 */ 850#ifndef __FreeBSD__ 851 struct bsd_ucred ucred_cache; 852#else 853 struct ucred *ucred_cache = NULL; 854#endif 855 int ucred_lookup = 0; 856 857 /* 858 * oif | args->oif If NULL, ipfw_chk has been called on the 859 * inbound path (ether_input, ip_input). 860 * If non-NULL, ipfw_chk has been called on the outbound path 861 * (ether_output, ip_output). 862 */ 863 struct ifnet *oif = args->oif; 864 865 int f_pos = 0; /* index of current rule in the array */ 866 int retval = 0; 867 868 /* 869 * hlen The length of the IP header. 870 */ 871 u_int hlen = 0; /* hlen >0 means we have an IP pkt */ 872 873 /* 874 * offset The offset of a fragment. offset != 0 means that 875 * we have a fragment at this offset of an IPv4 packet. 876 * offset == 0 means that (if this is an IPv4 packet) 877 * this is the first or only fragment. 878 * For IPv6 offset|ip6f_mf == 0 means there is no Fragment Header 879 * or there is a single packet fragement (fragement header added 880 * without needed). We will treat a single packet fragment as if 881 * there was no fragment header (or log/block depending on the 882 * V_fw_permit_single_frag6 sysctl setting). 883 */ 884 u_short offset = 0; 885 u_short ip6f_mf = 0; 886 887 /* 888 * Local copies of addresses. They are only valid if we have 889 * an IP packet. 890 * 891 * proto The protocol. Set to 0 for non-ip packets, 892 * or to the protocol read from the packet otherwise. 893 * proto != 0 means that we have an IPv4 packet. 894 * 895 * src_port, dst_port port numbers, in HOST format. Only 896 * valid for TCP and UDP packets. 897 * 898 * src_ip, dst_ip ip addresses, in NETWORK format. 899 * Only valid for IPv4 packets. 900 */ 901 uint8_t proto; 902 uint16_t src_port = 0, dst_port = 0; /* NOTE: host format */ 903 struct in_addr src_ip, dst_ip; /* NOTE: network format */ 904 uint16_t iplen=0; 905 int pktlen; 906 uint16_t etype = 0; /* Host order stored ether type */ 907 908 /* 909 * dyn_dir = MATCH_UNKNOWN when rules unchecked, 910 * MATCH_NONE when checked and not matched (q = NULL), 911 * MATCH_FORWARD or MATCH_REVERSE otherwise (q != NULL) 912 */ 913 int dyn_dir = MATCH_UNKNOWN; 914 ipfw_dyn_rule *q = NULL; 915 struct ip_fw_chain *chain = &V_layer3_chain; 916 917 /* 918 * We store in ulp a pointer to the upper layer protocol header. 919 * In the ipv4 case this is easy to determine from the header, 920 * but for ipv6 we might have some additional headers in the middle. 921 * ulp is NULL if not found. 922 */ 923 void *ulp = NULL; /* upper layer protocol pointer. */ 924 925 /* XXX ipv6 variables */ 926 int is_ipv6 = 0; 927 uint8_t icmp6_type = 0; 928 uint16_t ext_hd = 0; /* bits vector for extension header filtering */ 929 /* end of ipv6 variables */ 930 931 int is_ipv4 = 0; 932 933 int done = 0; /* flag to exit the outer loop */ 934 935 if (m->m_flags & M_SKIP_FIREWALL || (! V_ipfw_vnet_ready)) 936 return (IP_FW_PASS); /* accept */ 937 938 dst_ip.s_addr = 0; /* make sure it is initialized */ 939 src_ip.s_addr = 0; /* make sure it is initialized */ 940 pktlen = m->m_pkthdr.len; 941 args->f_id.fib = M_GETFIB(m); /* note mbuf not altered) */ 942 proto = args->f_id.proto = 0; /* mark f_id invalid */ 943 /* XXX 0 is a valid proto: IP/IPv6 Hop-by-Hop Option */ 944 945/* 946 * PULLUP_TO(len, p, T) makes sure that len + sizeof(T) is contiguous, 947 * then it sets p to point at the offset "len" in the mbuf. WARNING: the 948 * pointer might become stale after other pullups (but we never use it 949 * this way). 950 */ 951#define PULLUP_TO(_len, p, T) PULLUP_LEN(_len, p, sizeof(T)) 952#define PULLUP_LEN(_len, p, T) \ 953do { \ 954 int x = (_len) + T; \ 955 if ((m)->m_len < x) { \ 956 args->m = m = m_pullup(m, x); \ 957 if (m == NULL) \ 958 goto pullup_failed; \ 959 } \ 960 p = (mtod(m, char *) + (_len)); \ 961} while (0) 962 963 /* 964 * if we have an ether header, 965 */ 966 if (args->eh) 967 etype = ntohs(args->eh->ether_type); 968 969 /* Identify IP packets and fill up variables. */ 970 if (pktlen >= sizeof(struct ip6_hdr) && 971 (args->eh == NULL || etype == ETHERTYPE_IPV6) && ip->ip_v == 6) { 972 struct ip6_hdr *ip6 = (struct ip6_hdr *)ip; 973 is_ipv6 = 1; 974 args->f_id.addr_type = 6; 975 hlen = sizeof(struct ip6_hdr); 976 proto = ip6->ip6_nxt; 977 978 /* Search extension headers to find upper layer protocols */ 979 while (ulp == NULL && offset == 0) { 980 switch (proto) { 981 case IPPROTO_ICMPV6: 982 PULLUP_TO(hlen, ulp, struct icmp6_hdr); 983 icmp6_type = ICMP6(ulp)->icmp6_type; 984 break; 985 986 case IPPROTO_TCP: 987 PULLUP_TO(hlen, ulp, struct tcphdr); 988 dst_port = TCP(ulp)->th_dport; 989 src_port = TCP(ulp)->th_sport; 990 /* save flags for dynamic rules */ 991 args->f_id._flags = TCP(ulp)->th_flags; 992 break; 993 994 case IPPROTO_SCTP: 995 PULLUP_TO(hlen, ulp, struct sctphdr); 996 src_port = SCTP(ulp)->src_port; 997 dst_port = SCTP(ulp)->dest_port; 998 break; 999 1000 case IPPROTO_UDP: 1001 PULLUP_TO(hlen, ulp, struct udphdr); 1002 dst_port = UDP(ulp)->uh_dport; 1003 src_port = UDP(ulp)->uh_sport; 1004 break; 1005 1006 case IPPROTO_HOPOPTS: /* RFC 2460 */ 1007 PULLUP_TO(hlen, ulp, struct ip6_hbh); 1008 ext_hd |= EXT_HOPOPTS; 1009 hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3; 1010 proto = ((struct ip6_hbh *)ulp)->ip6h_nxt; 1011 ulp = NULL; 1012 break; 1013 1014 case IPPROTO_ROUTING: /* RFC 2460 */ 1015 PULLUP_TO(hlen, ulp, struct ip6_rthdr); 1016 switch (((struct ip6_rthdr *)ulp)->ip6r_type) { 1017 case 0: 1018 ext_hd |= EXT_RTHDR0; 1019 break; 1020 case 2: 1021 ext_hd |= EXT_RTHDR2; 1022 break; 1023 default: 1024 if (V_fw_verbose) 1025 printf("IPFW2: IPV6 - Unknown " 1026 "Routing Header type(%d)\n", 1027 ((struct ip6_rthdr *) 1028 ulp)->ip6r_type); 1029 if (V_fw_deny_unknown_exthdrs) 1030 return (IP_FW_DENY); 1031 break; 1032 } 1033 ext_hd |= EXT_ROUTING; 1034 hlen += (((struct ip6_rthdr *)ulp)->ip6r_len + 1) << 3; 1035 proto = ((struct ip6_rthdr *)ulp)->ip6r_nxt; 1036 ulp = NULL; 1037 break; 1038 1039 case IPPROTO_FRAGMENT: /* RFC 2460 */ 1040 PULLUP_TO(hlen, ulp, struct ip6_frag); 1041 ext_hd |= EXT_FRAGMENT; 1042 hlen += sizeof (struct ip6_frag); 1043 proto = ((struct ip6_frag *)ulp)->ip6f_nxt; 1044 offset = ((struct ip6_frag *)ulp)->ip6f_offlg & 1045 IP6F_OFF_MASK; 1046 ip6f_mf = ((struct ip6_frag *)ulp)->ip6f_offlg & 1047 IP6F_MORE_FRAG; 1048 if (V_fw_permit_single_frag6 == 0 && 1049 offset == 0 && ip6f_mf == 0) { 1050 if (V_fw_verbose) 1051 printf("IPFW2: IPV6 - Invalid " 1052 "Fragment Header\n"); 1053 if (V_fw_deny_unknown_exthdrs) 1054 return (IP_FW_DENY); 1055 break; 1056 } 1057 args->f_id.extra = 1058 ntohl(((struct ip6_frag *)ulp)->ip6f_ident); 1059 ulp = NULL; 1060 break; 1061 1062 case IPPROTO_DSTOPTS: /* RFC 2460 */ 1063 PULLUP_TO(hlen, ulp, struct ip6_hbh); 1064 ext_hd |= EXT_DSTOPTS; 1065 hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3; 1066 proto = ((struct ip6_hbh *)ulp)->ip6h_nxt; 1067 ulp = NULL; 1068 break; 1069 1070 case IPPROTO_AH: /* RFC 2402 */ 1071 PULLUP_TO(hlen, ulp, struct ip6_ext); 1072 ext_hd |= EXT_AH; 1073 hlen += (((struct ip6_ext *)ulp)->ip6e_len + 2) << 2; 1074 proto = ((struct ip6_ext *)ulp)->ip6e_nxt; 1075 ulp = NULL; 1076 break; 1077 1078 case IPPROTO_ESP: /* RFC 2406 */ 1079 PULLUP_TO(hlen, ulp, uint32_t); /* SPI, Seq# */ 1080 /* Anything past Seq# is variable length and 1081 * data past this ext. header is encrypted. */ 1082 ext_hd |= EXT_ESP; 1083 break; 1084 1085 case IPPROTO_NONE: /* RFC 2460 */ 1086 /* 1087 * Packet ends here, and IPv6 header has 1088 * already been pulled up. If ip6e_len!=0 1089 * then octets must be ignored. 1090 */ 1091 ulp = ip; /* non-NULL to get out of loop. */ 1092 break; 1093 1094 case IPPROTO_OSPFIGP: 1095 /* XXX OSPF header check? */ 1096 PULLUP_TO(hlen, ulp, struct ip6_ext); 1097 break; 1098 1099 case IPPROTO_PIM: 1100 /* XXX PIM header check? */ 1101 PULLUP_TO(hlen, ulp, struct pim); 1102 break; 1103 1104 case IPPROTO_CARP: 1105 PULLUP_TO(hlen, ulp, struct carp_header); 1106 if (((struct carp_header *)ulp)->carp_version != 1107 CARP_VERSION) 1108 return (IP_FW_DENY); 1109 if (((struct carp_header *)ulp)->carp_type != 1110 CARP_ADVERTISEMENT) 1111 return (IP_FW_DENY); 1112 break; 1113 1114 case IPPROTO_IPV6: /* RFC 2893 */ 1115 PULLUP_TO(hlen, ulp, struct ip6_hdr); 1116 break; 1117 1118 case IPPROTO_IPV4: /* RFC 2893 */ 1119 PULLUP_TO(hlen, ulp, struct ip); 1120 break; 1121 1122 default: 1123 if (V_fw_verbose) 1124 printf("IPFW2: IPV6 - Unknown " 1125 "Extension Header(%d), ext_hd=%x\n", 1126 proto, ext_hd); 1127 if (V_fw_deny_unknown_exthdrs) 1128 return (IP_FW_DENY); 1129 PULLUP_TO(hlen, ulp, struct ip6_ext); 1130 break; 1131 } /*switch */ 1132 } 1133 ip = mtod(m, struct ip *); 1134 ip6 = (struct ip6_hdr *)ip; 1135 args->f_id.src_ip6 = ip6->ip6_src; 1136 args->f_id.dst_ip6 = ip6->ip6_dst; 1137 args->f_id.src_ip = 0; 1138 args->f_id.dst_ip = 0; 1139 args->f_id.flow_id6 = ntohl(ip6->ip6_flow); 1140 } else if (pktlen >= sizeof(struct ip) && 1141 (args->eh == NULL || etype == ETHERTYPE_IP) && ip->ip_v == 4) { 1142 is_ipv4 = 1; 1143 hlen = ip->ip_hl << 2; 1144 args->f_id.addr_type = 4; 1145 1146 /* 1147 * Collect parameters into local variables for faster matching. 1148 */ 1149 proto = ip->ip_p; 1150 src_ip = ip->ip_src; 1151 dst_ip = ip->ip_dst; 1152 offset = ntohs(ip->ip_off) & IP_OFFMASK; 1153 iplen = ntohs(ip->ip_len); 1154 pktlen = iplen < pktlen ? iplen : pktlen; 1155 1156 if (offset == 0) { 1157 switch (proto) { 1158 case IPPROTO_TCP: 1159 PULLUP_TO(hlen, ulp, struct tcphdr); 1160 dst_port = TCP(ulp)->th_dport; 1161 src_port = TCP(ulp)->th_sport; 1162 /* save flags for dynamic rules */ 1163 args->f_id._flags = TCP(ulp)->th_flags; 1164 break; 1165 1166 case IPPROTO_SCTP: 1167 PULLUP_TO(hlen, ulp, struct sctphdr); 1168 src_port = SCTP(ulp)->src_port; 1169 dst_port = SCTP(ulp)->dest_port; 1170 break; 1171 1172 case IPPROTO_UDP: 1173 PULLUP_TO(hlen, ulp, struct udphdr); 1174 dst_port = UDP(ulp)->uh_dport; 1175 src_port = UDP(ulp)->uh_sport; 1176 break; 1177 1178 case IPPROTO_ICMP: 1179 PULLUP_TO(hlen, ulp, struct icmphdr); 1180 //args->f_id.flags = ICMP(ulp)->icmp_type; 1181 break; 1182 1183 default: 1184 break; 1185 } 1186 } 1187 1188 ip = mtod(m, struct ip *); 1189 args->f_id.src_ip = ntohl(src_ip.s_addr); 1190 args->f_id.dst_ip = ntohl(dst_ip.s_addr); 1191 } 1192#undef PULLUP_TO 1193 if (proto) { /* we may have port numbers, store them */ 1194 args->f_id.proto = proto; 1195 args->f_id.src_port = src_port = ntohs(src_port); 1196 args->f_id.dst_port = dst_port = ntohs(dst_port); 1197 } 1198 1199 IPFW_RLOCK(chain); 1200 if (! V_ipfw_vnet_ready) { /* shutting down, leave NOW. */ 1201 IPFW_RUNLOCK(chain); 1202 return (IP_FW_PASS); /* accept */ 1203 } 1204 if (args->rule.slot) { 1205 /* 1206 * Packet has already been tagged as a result of a previous 1207 * match on rule args->rule aka args->rule_id (PIPE, QUEUE, 1208 * REASS, NETGRAPH, DIVERT/TEE...) 1209 * Validate the slot and continue from the next one 1210 * if still present, otherwise do a lookup. 1211 */ 1212 f_pos = (args->rule.chain_id == chain->id) ? 1213 args->rule.slot : 1214 ipfw_find_rule(chain, args->rule.rulenum, 1215 args->rule.rule_id); 1216 } else { 1217 f_pos = 0; 1218 } 1219 1220 /* 1221 * Now scan the rules, and parse microinstructions for each rule. 1222 * We have two nested loops and an inner switch. Sometimes we 1223 * need to break out of one or both loops, or re-enter one of 1224 * the loops with updated variables. Loop variables are: 1225 * 1226 * f_pos (outer loop) points to the current rule. 1227 * On output it points to the matching rule. 1228 * done (outer loop) is used as a flag to break the loop. 1229 * l (inner loop) residual length of current rule. 1230 * cmd points to the current microinstruction. 1231 * 1232 * We break the inner loop by setting l=0 and possibly 1233 * cmdlen=0 if we don't want to advance cmd. 1234 * We break the outer loop by setting done=1 1235 * We can restart the inner loop by setting l>0 and f_pos, f, cmd 1236 * as needed. 1237 */ 1238 for (; f_pos < chain->n_rules; f_pos++) { 1239 ipfw_insn *cmd; 1240 uint32_t tablearg = 0; 1241 int l, cmdlen, skip_or; /* skip rest of OR block */ 1242 struct ip_fw *f; 1243 1244 f = chain->map[f_pos]; 1245 if (V_set_disable & (1 << f->set) ) 1246 continue; 1247 1248 skip_or = 0; 1249 for (l = f->cmd_len, cmd = f->cmd ; l > 0 ; 1250 l -= cmdlen, cmd += cmdlen) { 1251 int match; 1252 1253 /* 1254 * check_body is a jump target used when we find a 1255 * CHECK_STATE, and need to jump to the body of 1256 * the target rule. 1257 */ 1258 1259/* check_body: */ 1260 cmdlen = F_LEN(cmd); 1261 /* 1262 * An OR block (insn_1 || .. || insn_n) has the 1263 * F_OR bit set in all but the last instruction. 1264 * The first match will set "skip_or", and cause 1265 * the following instructions to be skipped until 1266 * past the one with the F_OR bit clear. 1267 */ 1268 if (skip_or) { /* skip this instruction */ 1269 if ((cmd->len & F_OR) == 0) 1270 skip_or = 0; /* next one is good */ 1271 continue; 1272 } 1273 match = 0; /* set to 1 if we succeed */ 1274 1275 switch (cmd->opcode) { 1276 /* 1277 * The first set of opcodes compares the packet's 1278 * fields with some pattern, setting 'match' if a 1279 * match is found. At the end of the loop there is 1280 * logic to deal with F_NOT and F_OR flags associated 1281 * with the opcode. 1282 */ 1283 case O_NOP: 1284 match = 1; 1285 break; 1286 1287 case O_FORWARD_MAC: 1288 printf("ipfw: opcode %d unimplemented\n", 1289 cmd->opcode); 1290 break; 1291 1292 case O_GID: 1293 case O_UID: 1294 case O_JAIL: 1295 /* 1296 * We only check offset == 0 && proto != 0, 1297 * as this ensures that we have a 1298 * packet with the ports info. 1299 */ 1300 if (offset != 0) 1301 break; 1302 if (proto == IPPROTO_TCP || 1303 proto == IPPROTO_UDP) 1304 match = check_uidgid( 1305 (ipfw_insn_u32 *)cmd, 1306 args, &ucred_lookup, 1307#ifdef __FreeBSD__ 1308 &ucred_cache); 1309#else 1310 (void *)&ucred_cache); 1311#endif 1312 break; 1313 1314 case O_RECV: 1315 match = iface_match(m->m_pkthdr.rcvif, 1316 (ipfw_insn_if *)cmd); 1317 break; 1318 1319 case O_XMIT: 1320 match = iface_match(oif, (ipfw_insn_if *)cmd); 1321 break; 1322 1323 case O_VIA: 1324 match = iface_match(oif ? oif : 1325 m->m_pkthdr.rcvif, (ipfw_insn_if *)cmd); 1326 break; 1327 1328 case O_MACADDR2: 1329 if (args->eh != NULL) { /* have MAC header */ 1330 u_int32_t *want = (u_int32_t *) 1331 ((ipfw_insn_mac *)cmd)->addr; 1332 u_int32_t *mask = (u_int32_t *) 1333 ((ipfw_insn_mac *)cmd)->mask; 1334 u_int32_t *hdr = (u_int32_t *)args->eh; 1335 1336 match = 1337 ( want[0] == (hdr[0] & mask[0]) && 1338 want[1] == (hdr[1] & mask[1]) && 1339 want[2] == (hdr[2] & mask[2]) ); 1340 } 1341 break; 1342 1343 case O_MAC_TYPE: 1344 if (args->eh != NULL) { 1345 u_int16_t *p = 1346 ((ipfw_insn_u16 *)cmd)->ports; 1347 int i; 1348 1349 for (i = cmdlen - 1; !match && i>0; 1350 i--, p += 2) 1351 match = (etype >= p[0] && 1352 etype <= p[1]); 1353 } 1354 break; 1355 1356 case O_FRAG: 1357 match = (offset != 0); 1358 break; 1359 1360 case O_IN: /* "out" is "not in" */ 1361 match = (oif == NULL); 1362 break; 1363 1364 case O_LAYER2: 1365 match = (args->eh != NULL); 1366 break; 1367 1368 case O_DIVERTED: 1369 { 1370 /* For diverted packets, args->rule.info 1371 * contains the divert port (in host format) 1372 * reason and direction. 1373 */ 1374 uint32_t i = args->rule.info; 1375 match = (i&IPFW_IS_MASK) == IPFW_IS_DIVERT && 1376 cmd->arg1 & ((i & IPFW_INFO_IN) ? 1 : 2); 1377 } 1378 break; 1379 1380 case O_PROTO: 1381 /* 1382 * We do not allow an arg of 0 so the 1383 * check of "proto" only suffices. 1384 */ 1385 match = (proto == cmd->arg1); 1386 break; 1387 1388 case O_IP_SRC: 1389 match = is_ipv4 && 1390 (((ipfw_insn_ip *)cmd)->addr.s_addr == 1391 src_ip.s_addr); 1392 break; 1393 1394 case O_IP_SRC_LOOKUP: 1395 case O_IP_DST_LOOKUP: 1396 if (is_ipv4) { 1397 uint32_t key = 1398 (cmd->opcode == O_IP_DST_LOOKUP) ? 1399 dst_ip.s_addr : src_ip.s_addr; 1400 uint32_t v = 0; 1401 1402 if (cmdlen > F_INSN_SIZE(ipfw_insn_u32)) { 1403 /* generic lookup. The key must be 1404 * in 32bit big-endian format. 1405 */ 1406 v = ((ipfw_insn_u32 *)cmd)->d[1]; 1407 if (v == 0) 1408 key = dst_ip.s_addr; 1409 else if (v == 1) 1410 key = src_ip.s_addr; 1411 else if (v == 6) /* dscp */ 1412 key = (ip->ip_tos >> 2) & 0x3f; 1413 else if (offset != 0) 1414 break; 1415 else if (proto != IPPROTO_TCP && 1416 proto != IPPROTO_UDP) 1417 break; 1418 else if (v == 2) 1419 key = htonl(dst_port); 1420 else if (v == 3) 1421 key = htonl(src_port); 1422 else if (v == 4 || v == 5) { 1423 check_uidgid( 1424 (ipfw_insn_u32 *)cmd, 1425 args, &ucred_lookup, 1426#ifdef __FreeBSD__ 1427 &ucred_cache); 1428 if (v == 4 /* O_UID */) 1429 key = ucred_cache->cr_uid; 1430 else if (v == 5 /* O_JAIL */) 1431 key = ucred_cache->cr_prison->pr_id; 1432#else /* !__FreeBSD__ */ 1433 (void *)&ucred_cache); 1434 if (v ==4 /* O_UID */) 1435 key = ucred_cache.uid; 1436 else if (v == 5 /* O_JAIL */) 1437 key = ucred_cache.xid; 1438#endif /* !__FreeBSD__ */ 1439 key = htonl(key); 1440 } else 1441 break; 1442 } 1443 match = ipfw_lookup_table(chain, 1444 cmd->arg1, key, &v); 1445 if (!match) 1446 break; 1447 if (cmdlen == F_INSN_SIZE(ipfw_insn_u32)) 1448 match = 1449 ((ipfw_insn_u32 *)cmd)->d[0] == v; 1450 else 1451 tablearg = v; 1452 } 1453 break; 1454 1455 case O_IP_SRC_MASK: 1456 case O_IP_DST_MASK: 1457 if (is_ipv4) { 1458 uint32_t a = 1459 (cmd->opcode == O_IP_DST_MASK) ? 1460 dst_ip.s_addr : src_ip.s_addr; 1461 uint32_t *p = ((ipfw_insn_u32 *)cmd)->d; 1462 int i = cmdlen-1; 1463 1464 for (; !match && i>0; i-= 2, p+= 2) 1465 match = (p[0] == (a & p[1])); 1466 } 1467 break; 1468 1469 case O_IP_SRC_ME: 1470 if (is_ipv4) { 1471 struct ifnet *tif; 1472 1473 INADDR_TO_IFP(src_ip, tif); 1474 match = (tif != NULL); 1475 break; 1476 } 1477#ifdef INET6 1478 /* FALLTHROUGH */ 1479 case O_IP6_SRC_ME: 1480 match= is_ipv6 && search_ip6_addr_net(&args->f_id.src_ip6); 1481#endif 1482 break; 1483 1484 case O_IP_DST_SET: 1485 case O_IP_SRC_SET: 1486 if (is_ipv4) { 1487 u_int32_t *d = (u_int32_t *)(cmd+1); 1488 u_int32_t addr = 1489 cmd->opcode == O_IP_DST_SET ? 1490 args->f_id.dst_ip : 1491 args->f_id.src_ip; 1492 1493 if (addr < d[0]) 1494 break; 1495 addr -= d[0]; /* subtract base */ 1496 match = (addr < cmd->arg1) && 1497 ( d[ 1 + (addr>>5)] & 1498 (1<<(addr & 0x1f)) ); 1499 } 1500 break; 1501 1502 case O_IP_DST: 1503 match = is_ipv4 && 1504 (((ipfw_insn_ip *)cmd)->addr.s_addr == 1505 dst_ip.s_addr); 1506 break; 1507 1508 case O_IP_DST_ME: 1509 if (is_ipv4) { 1510 struct ifnet *tif; 1511 1512 INADDR_TO_IFP(dst_ip, tif); 1513 match = (tif != NULL); 1514 break; 1515 } 1516#ifdef INET6 1517 /* FALLTHROUGH */ 1518 case O_IP6_DST_ME: 1519 match= is_ipv6 && search_ip6_addr_net(&args->f_id.dst_ip6); 1520#endif 1521 break; 1522 1523 1524 case O_IP_SRCPORT: 1525 case O_IP_DSTPORT: 1526 /* 1527 * offset == 0 && proto != 0 is enough 1528 * to guarantee that we have a 1529 * packet with port info. 1530 */ 1531 if ((proto==IPPROTO_UDP || proto==IPPROTO_TCP) 1532 && offset == 0) { 1533 u_int16_t x = 1534 (cmd->opcode == O_IP_SRCPORT) ? 1535 src_port : dst_port ; 1536 u_int16_t *p = 1537 ((ipfw_insn_u16 *)cmd)->ports; 1538 int i; 1539 1540 for (i = cmdlen - 1; !match && i>0; 1541 i--, p += 2) 1542 match = (x>=p[0] && x<=p[1]); 1543 } 1544 break; 1545 1546 case O_ICMPTYPE: 1547 match = (offset == 0 && proto==IPPROTO_ICMP && 1548 icmptype_match(ICMP(ulp), (ipfw_insn_u32 *)cmd) ); 1549 break; 1550 1551#ifdef INET6 1552 case O_ICMP6TYPE: 1553 match = is_ipv6 && offset == 0 && 1554 proto==IPPROTO_ICMPV6 && 1555 icmp6type_match( 1556 ICMP6(ulp)->icmp6_type, 1557 (ipfw_insn_u32 *)cmd); 1558 break; 1559#endif /* INET6 */ 1560 1561 case O_IPOPT: 1562 match = (is_ipv4 && 1563 ipopts_match(ip, cmd) ); 1564 break; 1565 1566 case O_IPVER: 1567 match = (is_ipv4 && 1568 cmd->arg1 == ip->ip_v); 1569 break; 1570 1571 case O_IPID: 1572 case O_IPLEN: 1573 case O_IPTTL: 1574 if (is_ipv4) { /* only for IP packets */ 1575 uint16_t x; 1576 uint16_t *p; 1577 int i; 1578 1579 if (cmd->opcode == O_IPLEN) 1580 x = iplen; 1581 else if (cmd->opcode == O_IPTTL) 1582 x = ip->ip_ttl; 1583 else /* must be IPID */ 1584 x = ntohs(ip->ip_id); 1585 if (cmdlen == 1) { 1586 match = (cmd->arg1 == x); 1587 break; 1588 } 1589 /* otherwise we have ranges */ 1590 p = ((ipfw_insn_u16 *)cmd)->ports; 1591 i = cmdlen - 1; 1592 for (; !match && i>0; i--, p += 2) 1593 match = (x >= p[0] && x <= p[1]); 1594 } 1595 break; 1596 1597 case O_IPPRECEDENCE: 1598 match = (is_ipv4 && 1599 (cmd->arg1 == (ip->ip_tos & 0xe0)) ); 1600 break; 1601 1602 case O_IPTOS: 1603 match = (is_ipv4 && 1604 flags_match(cmd, ip->ip_tos)); 1605 break; 1606 1607 case O_TCPDATALEN: 1608 if (proto == IPPROTO_TCP && offset == 0) { 1609 struct tcphdr *tcp; 1610 uint16_t x; 1611 uint16_t *p; 1612 int i; 1613 1614 tcp = TCP(ulp); 1615 x = iplen - 1616 ((ip->ip_hl + tcp->th_off) << 2); 1617 if (cmdlen == 1) { 1618 match = (cmd->arg1 == x); 1619 break; 1620 } 1621 /* otherwise we have ranges */ 1622 p = ((ipfw_insn_u16 *)cmd)->ports; 1623 i = cmdlen - 1; 1624 for (; !match && i>0; i--, p += 2) 1625 match = (x >= p[0] && x <= p[1]); 1626 } 1627 break; 1628 1629 case O_TCPFLAGS: 1630 match = (proto == IPPROTO_TCP && offset == 0 && 1631 flags_match(cmd, TCP(ulp)->th_flags)); 1632 break; 1633 1634 case O_TCPOPTS: 1635 PULLUP_LEN(hlen, ulp, (TCP(ulp)->th_off << 2)); 1636 match = (proto == IPPROTO_TCP && offset == 0 && 1637 tcpopts_match(TCP(ulp), cmd)); 1638 break; 1639 1640 case O_TCPSEQ: 1641 match = (proto == IPPROTO_TCP && offset == 0 && 1642 ((ipfw_insn_u32 *)cmd)->d[0] == 1643 TCP(ulp)->th_seq); 1644 break; 1645 1646 case O_TCPACK: 1647 match = (proto == IPPROTO_TCP && offset == 0 && 1648 ((ipfw_insn_u32 *)cmd)->d[0] == 1649 TCP(ulp)->th_ack); 1650 break; 1651 1652 case O_TCPWIN: 1653 match = (proto == IPPROTO_TCP && offset == 0 && 1654 cmd->arg1 == TCP(ulp)->th_win); 1655 break; 1656 1657 case O_ESTAB: 1658 /* reject packets which have SYN only */ 1659 /* XXX should i also check for TH_ACK ? */ 1660 match = (proto == IPPROTO_TCP && offset == 0 && 1661 (TCP(ulp)->th_flags & 1662 (TH_RST | TH_ACK | TH_SYN)) != TH_SYN); 1663 break; 1664 1665 case O_ALTQ: { 1666 struct pf_mtag *at; 1667 ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd; 1668 1669 match = 1; 1670 at = pf_find_mtag(m); 1671 if (at != NULL && at->qid != 0) 1672 break; 1673 at = pf_get_mtag(m); 1674 if (at == NULL) { 1675 /* 1676 * Let the packet fall back to the 1677 * default ALTQ. 1678 */ 1679 break; 1680 } 1681 at->qid = altq->qid; 1682 at->hdr = ip; 1683 break; 1684 } 1685 1686 case O_LOG: 1687 ipfw_log(f, hlen, args, m, 1688 oif, offset | ip6f_mf, tablearg, ip); 1689 match = 1; 1690 break; 1691 1692 case O_PROB: 1693 match = (random()<((ipfw_insn_u32 *)cmd)->d[0]); 1694 break; 1695 1696 case O_VERREVPATH: 1697 /* Outgoing packets automatically pass/match */ 1698 match = ((oif != NULL) || 1699 (m->m_pkthdr.rcvif == NULL) || 1700 ( 1701#ifdef INET6 1702 is_ipv6 ? 1703 verify_path6(&(args->f_id.src_ip6), 1704 m->m_pkthdr.rcvif) : 1705#endif 1706 verify_path(src_ip, m->m_pkthdr.rcvif, 1707 args->f_id.fib))); 1708 break; 1709 1710 case O_VERSRCREACH: 1711 /* Outgoing packets automatically pass/match */ 1712 match = (hlen > 0 && ((oif != NULL) || 1713#ifdef INET6 1714 is_ipv6 ? 1715 verify_path6(&(args->f_id.src_ip6), 1716 NULL) : 1717#endif 1718 verify_path(src_ip, NULL, args->f_id.fib))); 1719 break; 1720 1721 case O_ANTISPOOF: 1722 /* Outgoing packets automatically pass/match */ 1723 if (oif == NULL && hlen > 0 && 1724 ( (is_ipv4 && in_localaddr(src_ip)) 1725#ifdef INET6 1726 || (is_ipv6 && 1727 in6_localaddr(&(args->f_id.src_ip6))) 1728#endif 1729 )) 1730 match = 1731#ifdef INET6 1732 is_ipv6 ? verify_path6( 1733 &(args->f_id.src_ip6), 1734 m->m_pkthdr.rcvif) : 1735#endif 1736 verify_path(src_ip, 1737 m->m_pkthdr.rcvif, 1738 args->f_id.fib); 1739 else 1740 match = 1; 1741 break; 1742 1743 case O_IPSEC: 1744#ifdef IPSEC 1745 match = (m_tag_find(m, 1746 PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL); 1747#endif 1748 /* otherwise no match */ 1749 break; 1750 1751#ifdef INET6 1752 case O_IP6_SRC: 1753 match = is_ipv6 && 1754 IN6_ARE_ADDR_EQUAL(&args->f_id.src_ip6, 1755 &((ipfw_insn_ip6 *)cmd)->addr6); 1756 break; 1757 1758 case O_IP6_DST: 1759 match = is_ipv6 && 1760 IN6_ARE_ADDR_EQUAL(&args->f_id.dst_ip6, 1761 &((ipfw_insn_ip6 *)cmd)->addr6); 1762 break; 1763 case O_IP6_SRC_MASK: 1764 case O_IP6_DST_MASK: 1765 if (is_ipv6) { 1766 int i = cmdlen - 1; 1767 struct in6_addr p; 1768 struct in6_addr *d = 1769 &((ipfw_insn_ip6 *)cmd)->addr6; 1770 1771 for (; !match && i > 0; d += 2, 1772 i -= F_INSN_SIZE(struct in6_addr) 1773 * 2) { 1774 p = (cmd->opcode == 1775 O_IP6_SRC_MASK) ? 1776 args->f_id.src_ip6: 1777 args->f_id.dst_ip6; 1778 APPLY_MASK(&p, &d[1]); 1779 match = 1780 IN6_ARE_ADDR_EQUAL(&d[0], 1781 &p); 1782 } 1783 } 1784 break; 1785 1786 case O_FLOW6ID: 1787 match = is_ipv6 && 1788 flow6id_match(args->f_id.flow_id6, 1789 (ipfw_insn_u32 *) cmd); 1790 break; 1791 1792 case O_EXT_HDR: 1793 match = is_ipv6 && 1794 (ext_hd & ((ipfw_insn *) cmd)->arg1); 1795 break; 1796 1797 case O_IP6: 1798 match = is_ipv6; 1799 break; 1800#endif 1801 1802 case O_IP4: 1803 match = is_ipv4; 1804 break; 1805 1806 case O_TAG: { 1807 struct m_tag *mtag; 1808 uint32_t tag = (cmd->arg1 == IP_FW_TABLEARG) ? 1809 tablearg : cmd->arg1; 1810 1811 /* Packet is already tagged with this tag? */ 1812 mtag = m_tag_locate(m, MTAG_IPFW, tag, NULL); 1813 1814 /* We have `untag' action when F_NOT flag is 1815 * present. And we must remove this mtag from 1816 * mbuf and reset `match' to zero (`match' will 1817 * be inversed later). 1818 * Otherwise we should allocate new mtag and 1819 * push it into mbuf. 1820 */ 1821 if (cmd->len & F_NOT) { /* `untag' action */ 1822 if (mtag != NULL) 1823 m_tag_delete(m, mtag); 1824 match = 0; 1825 } else { 1826 if (mtag == NULL) { 1827 mtag = m_tag_alloc( MTAG_IPFW, 1828 tag, 0, M_NOWAIT); 1829 if (mtag != NULL) 1830 m_tag_prepend(m, mtag); 1831 } 1832 match = 1; 1833 } 1834 break; 1835 } 1836 1837 case O_FIB: /* try match the specified fib */ 1838 if (args->f_id.fib == cmd->arg1) 1839 match = 1; 1840 break; 1841 1842 case O_SOCKARG: { 1843 struct inpcb *inp = args->inp; 1844 struct inpcbinfo *pi; 1845 1846 if (is_ipv6) /* XXX can we remove this ? */ 1847 break; 1848 1849 if (proto == IPPROTO_TCP) 1850 pi = &V_tcbinfo; 1851 else if (proto == IPPROTO_UDP) 1852 pi = &V_udbinfo; 1853 else 1854 break; 1855 1856 /* 1857 * XXXRW: so_user_cookie should almost 1858 * certainly be inp_user_cookie? 1859 */ 1860 1861 /* For incomming packet, lookup up the 1862 inpcb using the src/dest ip/port tuple */ 1863 if (inp == NULL) { 1864 inp = in_pcblookup(pi, 1865 src_ip, htons(src_port), 1866 dst_ip, htons(dst_port), 1867 INPLOOKUP_RLOCKPCB, NULL); 1868 if (inp != NULL) { 1869 tablearg = 1870 inp->inp_socket->so_user_cookie; 1871 if (tablearg) 1872 match = 1; 1873 INP_RUNLOCK(inp); 1874 } 1875 } else { 1876 if (inp->inp_socket) { 1877 tablearg = 1878 inp->inp_socket->so_user_cookie; 1879 if (tablearg) 1880 match = 1; 1881 } 1882 } 1883 break; 1884 } 1885 1886 case O_TAGGED: { 1887 struct m_tag *mtag; 1888 uint32_t tag = (cmd->arg1 == IP_FW_TABLEARG) ? 1889 tablearg : cmd->arg1; 1890 1891 if (cmdlen == 1) { 1892 match = m_tag_locate(m, MTAG_IPFW, 1893 tag, NULL) != NULL; 1894 break; 1895 } 1896 1897 /* we have ranges */ 1898 for (mtag = m_tag_first(m); 1899 mtag != NULL && !match; 1900 mtag = m_tag_next(m, mtag)) { 1901 uint16_t *p; 1902 int i; 1903 1904 if (mtag->m_tag_cookie != MTAG_IPFW) 1905 continue; 1906 1907 p = ((ipfw_insn_u16 *)cmd)->ports; 1908 i = cmdlen - 1; 1909 for(; !match && i > 0; i--, p += 2) 1910 match = 1911 mtag->m_tag_id >= p[0] && 1912 mtag->m_tag_id <= p[1]; 1913 } 1914 break; 1915 } 1916 1917 /* 1918 * The second set of opcodes represents 'actions', 1919 * i.e. the terminal part of a rule once the packet 1920 * matches all previous patterns. 1921 * Typically there is only one action for each rule, 1922 * and the opcode is stored at the end of the rule 1923 * (but there are exceptions -- see below). 1924 * 1925 * In general, here we set retval and terminate the 1926 * outer loop (would be a 'break 3' in some language, 1927 * but we need to set l=0, done=1) 1928 * 1929 * Exceptions: 1930 * O_COUNT and O_SKIPTO actions: 1931 * instead of terminating, we jump to the next rule 1932 * (setting l=0), or to the SKIPTO target (setting 1933 * f/f_len, cmd and l as needed), respectively. 1934 * 1935 * O_TAG, O_LOG and O_ALTQ action parameters: 1936 * perform some action and set match = 1; 1937 * 1938 * O_LIMIT and O_KEEP_STATE: these opcodes are 1939 * not real 'actions', and are stored right 1940 * before the 'action' part of the rule. 1941 * These opcodes try to install an entry in the 1942 * state tables; if successful, we continue with 1943 * the next opcode (match=1; break;), otherwise 1944 * the packet must be dropped (set retval, 1945 * break loops with l=0, done=1) 1946 * 1947 * O_PROBE_STATE and O_CHECK_STATE: these opcodes 1948 * cause a lookup of the state table, and a jump 1949 * to the 'action' part of the parent rule 1950 * if an entry is found, or 1951 * (CHECK_STATE only) a jump to the next rule if 1952 * the entry is not found. 1953 * The result of the lookup is cached so that 1954 * further instances of these opcodes become NOPs. 1955 * The jump to the next rule is done by setting 1956 * l=0, cmdlen=0. 1957 */ 1958 case O_LIMIT: 1959 case O_KEEP_STATE: 1960 if (ipfw_install_state(f, 1961 (ipfw_insn_limit *)cmd, args, tablearg)) { 1962 /* error or limit violation */ 1963 retval = IP_FW_DENY; 1964 l = 0; /* exit inner loop */ 1965 done = 1; /* exit outer loop */ 1966 } 1967 match = 1; 1968 break; 1969 1970 case O_PROBE_STATE: 1971 case O_CHECK_STATE: 1972 /* 1973 * dynamic rules are checked at the first 1974 * keep-state or check-state occurrence, 1975 * with the result being stored in dyn_dir. 1976 * The compiler introduces a PROBE_STATE 1977 * instruction for us when we have a 1978 * KEEP_STATE (because PROBE_STATE needs 1979 * to be run first). 1980 */ 1981 if (dyn_dir == MATCH_UNKNOWN && 1982 (q = ipfw_lookup_dyn_rule(&args->f_id, 1983 &dyn_dir, proto == IPPROTO_TCP ? 1984 TCP(ulp) : NULL)) 1985 != NULL) { 1986 /* 1987 * Found dynamic entry, update stats 1988 * and jump to the 'action' part of 1989 * the parent rule by setting 1990 * f, cmd, l and clearing cmdlen. 1991 */ 1992 q->pcnt++; 1993 q->bcnt += pktlen; 1994 /* XXX we would like to have f_pos 1995 * readily accessible in the dynamic 1996 * rule, instead of having to 1997 * lookup q->rule. 1998 */ 1999 f = q->rule; 2000 f_pos = ipfw_find_rule(chain, 2001 f->rulenum, f->id); 2002 cmd = ACTION_PTR(f); 2003 l = f->cmd_len - f->act_ofs; 2004 ipfw_dyn_unlock(); 2005 cmdlen = 0; 2006 match = 1; 2007 break; 2008 } 2009 /* 2010 * Dynamic entry not found. If CHECK_STATE, 2011 * skip to next rule, if PROBE_STATE just 2012 * ignore and continue with next opcode. 2013 */ 2014 if (cmd->opcode == O_CHECK_STATE) 2015 l = 0; /* exit inner loop */ 2016 match = 1; 2017 break; 2018 2019 case O_ACCEPT: 2020 retval = 0; /* accept */ 2021 l = 0; /* exit inner loop */ 2022 done = 1; /* exit outer loop */ 2023 break; 2024 2025 case O_PIPE: 2026 case O_QUEUE: 2027 set_match(args, f_pos, chain); 2028 args->rule.info = (cmd->arg1 == IP_FW_TABLEARG) ? 2029 tablearg : cmd->arg1; 2030 if (cmd->opcode == O_PIPE) 2031 args->rule.info |= IPFW_IS_PIPE; 2032 if (V_fw_one_pass) 2033 args->rule.info |= IPFW_ONEPASS; 2034 retval = IP_FW_DUMMYNET; 2035 l = 0; /* exit inner loop */ 2036 done = 1; /* exit outer loop */ 2037 break; 2038 2039 case O_DIVERT: 2040 case O_TEE: 2041 if (args->eh) /* not on layer 2 */ 2042 break; 2043 /* otherwise this is terminal */ 2044 l = 0; /* exit inner loop */ 2045 done = 1; /* exit outer loop */ 2046 retval = (cmd->opcode == O_DIVERT) ? 2047 IP_FW_DIVERT : IP_FW_TEE; 2048 set_match(args, f_pos, chain); 2049 args->rule.info = (cmd->arg1 == IP_FW_TABLEARG) ? 2050 tablearg : cmd->arg1; 2051 break; 2052 2053 case O_COUNT: 2054 f->pcnt++; /* update stats */ 2055 f->bcnt += pktlen; 2056 f->timestamp = time_uptime; 2057 l = 0; /* exit inner loop */ 2058 break; 2059 2060 case O_SKIPTO: 2061 f->pcnt++; /* update stats */ 2062 f->bcnt += pktlen; 2063 f->timestamp = time_uptime; 2064 /* If possible use cached f_pos (in f->next_rule), 2065 * whose version is written in f->next_rule 2066 * (horrible hacks to avoid changing the ABI). 2067 */ 2068 if (cmd->arg1 != IP_FW_TABLEARG && 2069 (uintptr_t)f->x_next == chain->id) { 2070 f_pos = (uintptr_t)f->next_rule; 2071 } else { 2072 int i = (cmd->arg1 == IP_FW_TABLEARG) ? 2073 tablearg : cmd->arg1; 2074 /* make sure we do not jump backward */ 2075 if (i <= f->rulenum) 2076 i = f->rulenum + 1; 2077 f_pos = ipfw_find_rule(chain, i, 0); 2078 /* update the cache */ 2079 if (cmd->arg1 != IP_FW_TABLEARG) { 2080 f->next_rule = 2081 (void *)(uintptr_t)f_pos; 2082 f->x_next = 2083 (void *)(uintptr_t)chain->id; 2084 } 2085 } 2086 /* 2087 * Skip disabled rules, and re-enter 2088 * the inner loop with the correct 2089 * f_pos, f, l and cmd. 2090 * Also clear cmdlen and skip_or 2091 */ 2092 for (; f_pos < chain->n_rules - 1 && 2093 (V_set_disable & 2094 (1 << chain->map[f_pos]->set)); 2095 f_pos++) 2096 ; 2097 /* Re-enter the inner loop at the skipto rule. */ 2098 f = chain->map[f_pos]; 2099 l = f->cmd_len; 2100 cmd = f->cmd; 2101 match = 1; 2102 cmdlen = 0; 2103 skip_or = 0; 2104 continue; 2105 break; /* not reached */ 2106 2107 case O_CALLRETURN: { 2108 /* 2109 * Implementation of `subroutine' call/return, 2110 * in the stack carried in an mbuf tag. This 2111 * is different from `skipto' in that any call 2112 * address is possible (`skipto' must prevent 2113 * backward jumps to avoid endless loops). 2114 * We have `return' action when F_NOT flag is 2115 * present. The `m_tag_id' field is used as 2116 * stack pointer. 2117 */ 2118 struct m_tag *mtag; 2119 uint16_t jmpto, *stack; 2120 2121#define IS_CALL ((cmd->len & F_NOT) == 0) 2122#define IS_RETURN ((cmd->len & F_NOT) != 0) 2123 /* 2124 * Hand-rolled version of m_tag_locate() with 2125 * wildcard `type'. 2126 * If not already tagged, allocate new tag. 2127 */ 2128 mtag = m_tag_first(m); 2129 while (mtag != NULL) { 2130 if (mtag->m_tag_cookie == 2131 MTAG_IPFW_CALL) 2132 break; 2133 mtag = m_tag_next(m, mtag); 2134 } 2135 if (mtag == NULL && IS_CALL) { 2136 mtag = m_tag_alloc(MTAG_IPFW_CALL, 0, 2137 IPFW_CALLSTACK_SIZE * 2138 sizeof(uint16_t), M_NOWAIT); 2139 if (mtag != NULL) 2140 m_tag_prepend(m, mtag); 2141 } 2142 2143 /* 2144 * On error both `call' and `return' just 2145 * continue with next rule. 2146 */ 2147 if (IS_RETURN && (mtag == NULL || 2148 mtag->m_tag_id == 0)) { 2149 l = 0; /* exit inner loop */ 2150 break; 2151 } 2152 if (IS_CALL && (mtag == NULL || 2153 mtag->m_tag_id >= IPFW_CALLSTACK_SIZE)) { 2154 printf("ipfw: call stack error, " 2155 "go to next rule\n"); 2156 l = 0; /* exit inner loop */ 2157 break; 2158 } 2159 2160 f->pcnt++; /* update stats */ 2161 f->bcnt += pktlen; 2162 f->timestamp = time_uptime; 2163 stack = (uint16_t *)(mtag + 1); 2164 2165 /* 2166 * The `call' action may use cached f_pos 2167 * (in f->next_rule), whose version is written 2168 * in f->next_rule. 2169 * The `return' action, however, doesn't have 2170 * fixed jump address in cmd->arg1 and can't use 2171 * cache. 2172 */ 2173 if (IS_CALL) { 2174 stack[mtag->m_tag_id] = f->rulenum; 2175 mtag->m_tag_id++; 2176 if (cmd->arg1 != IP_FW_TABLEARG && 2177 (uintptr_t)f->x_next == chain->id) { 2178 f_pos = (uintptr_t)f->next_rule; 2179 } else { 2180 jmpto = (cmd->arg1 == 2181 IP_FW_TABLEARG) ? tablearg: 2182 cmd->arg1; 2183 f_pos = ipfw_find_rule(chain, 2184 jmpto, 0); 2185 /* update the cache */ 2186 if (cmd->arg1 != 2187 IP_FW_TABLEARG) { 2188 f->next_rule = 2189 (void *)(uintptr_t) 2190 f_pos; 2191 f->x_next = 2192 (void *)(uintptr_t) 2193 chain->id; 2194 } 2195 } 2196 } else { /* `return' action */ 2197 mtag->m_tag_id--; 2198 jmpto = stack[mtag->m_tag_id] + 1; 2199 f_pos = ipfw_find_rule(chain, jmpto, 0); 2200 } 2201 2202 /* 2203 * Skip disabled rules, and re-enter 2204 * the inner loop with the correct 2205 * f_pos, f, l and cmd. 2206 * Also clear cmdlen and skip_or 2207 */ 2208 for (; f_pos < chain->n_rules - 1 && 2209 (V_set_disable & 2210 (1 << chain->map[f_pos]->set)); f_pos++) 2211 ; 2212 /* Re-enter the inner loop at the dest rule. */ 2213 f = chain->map[f_pos]; 2214 l = f->cmd_len; 2215 cmd = f->cmd; 2216 cmdlen = 0; 2217 skip_or = 0; 2218 continue; 2219 break; /* NOTREACHED */ 2220 } 2221#undef IS_CALL 2222#undef IS_RETURN 2223 2224 case O_REJECT: 2225 /* 2226 * Drop the packet and send a reject notice 2227 * if the packet is not ICMP (or is an ICMP 2228 * query), and it is not multicast/broadcast. 2229 */ 2230 if (hlen > 0 && is_ipv4 && offset == 0 && 2231 (proto != IPPROTO_ICMP || 2232 is_icmp_query(ICMP(ulp))) && 2233 !(m->m_flags & (M_BCAST|M_MCAST)) && 2234 !IN_MULTICAST(ntohl(dst_ip.s_addr))) { 2235 send_reject(args, cmd->arg1, iplen, ip); 2236 m = args->m; 2237 } 2238 /* FALLTHROUGH */ 2239#ifdef INET6 2240 case O_UNREACH6: 2241 if (hlen > 0 && is_ipv6 && 2242 ((offset & IP6F_OFF_MASK) == 0) && 2243 (proto != IPPROTO_ICMPV6 || 2244 (is_icmp6_query(icmp6_type) == 1)) && 2245 !(m->m_flags & (M_BCAST|M_MCAST)) && 2246 !IN6_IS_ADDR_MULTICAST(&args->f_id.dst_ip6)) { 2247 send_reject6( 2248 args, cmd->arg1, hlen, 2249 (struct ip6_hdr *)ip); 2250 m = args->m; 2251 } 2252 /* FALLTHROUGH */ 2253#endif 2254 case O_DENY: 2255 retval = IP_FW_DENY; 2256 l = 0; /* exit inner loop */ 2257 done = 1; /* exit outer loop */ 2258 break; 2259 2260 case O_FORWARD_IP: 2261 if (args->eh) /* not valid on layer2 pkts */ 2262 break; 2263 if (q == NULL || q->rule != f || 2264 dyn_dir == MATCH_FORWARD) { 2265 struct sockaddr_in *sa; 2266 sa = &(((ipfw_insn_sa *)cmd)->sa); 2267 if (sa->sin_addr.s_addr == INADDR_ANY) { 2268 bcopy(sa, &args->hopstore, 2269 sizeof(*sa)); 2270 args->hopstore.sin_addr.s_addr = 2271 htonl(tablearg); 2272 args->next_hop = &args->hopstore; 2273 } else { 2274 args->next_hop = sa; 2275 } 2276 } 2277 retval = IP_FW_PASS; 2278 l = 0; /* exit inner loop */ 2279 done = 1; /* exit outer loop */ 2280 break; 2281 2282#ifdef INET6 2283 case O_FORWARD_IP6: 2284 if (args->eh) /* not valid on layer2 pkts */ 2285 break; 2286 if (q == NULL || q->rule != f || 2287 dyn_dir == MATCH_FORWARD) { 2288 struct sockaddr_in6 *sin6; 2289 2290 sin6 = &(((ipfw_insn_sa6 *)cmd)->sa); 2291 args->next_hop6 = sin6; 2292 } 2293 retval = IP_FW_PASS; 2294 l = 0; /* exit inner loop */ 2295 done = 1; /* exit outer loop */ 2296 break; 2297#endif 2298 2299 case O_NETGRAPH: 2300 case O_NGTEE: 2301 set_match(args, f_pos, chain); 2302 args->rule.info = (cmd->arg1 == IP_FW_TABLEARG) ? 2303 tablearg : cmd->arg1; 2304 if (V_fw_one_pass) 2305 args->rule.info |= IPFW_ONEPASS; 2306 retval = (cmd->opcode == O_NETGRAPH) ? 2307 IP_FW_NETGRAPH : IP_FW_NGTEE; 2308 l = 0; /* exit inner loop */ 2309 done = 1; /* exit outer loop */ 2310 break; 2311 2312 case O_SETFIB: { 2313 uint32_t fib; 2314 2315 f->pcnt++; /* update stats */ 2316 f->bcnt += pktlen; 2317 f->timestamp = time_uptime; 2318 fib = (cmd->arg1 == IP_FW_TABLEARG) ? tablearg: 2319 cmd->arg1; 2320 if (fib >= rt_numfibs) 2321 fib = 0; 2322 M_SETFIB(m, fib); 2323 args->f_id.fib = fib; 2324 l = 0; /* exit inner loop */ 2325 break; 2326 } 2327 2328 case O_NAT: 2329 if (!IPFW_NAT_LOADED) { 2330 retval = IP_FW_DENY; 2331 } else { 2332 struct cfg_nat *t; 2333 int nat_id; 2334 2335 set_match(args, f_pos, chain); 2336 /* Check if this is 'global' nat rule */ 2337 if (cmd->arg1 == 0) { 2338 retval = ipfw_nat_ptr(args, NULL, m); 2339 l = 0; 2340 done = 1; 2341 break; 2342 } 2343 t = ((ipfw_insn_nat *)cmd)->nat; 2344 if (t == NULL) { 2345 nat_id = (cmd->arg1 == IP_FW_TABLEARG) ? 2346 tablearg : cmd->arg1; 2347 t = (*lookup_nat_ptr)(&chain->nat, nat_id); 2348 2349 if (t == NULL) { 2350 retval = IP_FW_DENY; 2351 l = 0; /* exit inner loop */ 2352 done = 1; /* exit outer loop */ 2353 break; 2354 } 2355 if (cmd->arg1 != IP_FW_TABLEARG) 2356 ((ipfw_insn_nat *)cmd)->nat = t; 2357 } 2358 retval = ipfw_nat_ptr(args, t, m); 2359 } 2360 l = 0; /* exit inner loop */ 2361 done = 1; /* exit outer loop */ 2362 break; 2363 2364 case O_REASS: { 2365 int ip_off; 2366 2367 f->pcnt++; 2368 f->bcnt += pktlen; 2369 l = 0; /* in any case exit inner loop */ 2370 ip_off = ntohs(ip->ip_off); 2371 2372 /* if not fragmented, go to next rule */ 2373 if ((ip_off & (IP_MF | IP_OFFMASK)) == 0) 2374 break; 2375 /* 2376 * ip_reass() expects len & off in host 2377 * byte order. 2378 */ 2379 SET_HOST_IPLEN(ip); 2380 2381 args->m = m = ip_reass(m); 2382 2383 /* 2384 * do IP header checksum fixup. 2385 */ 2386 if (m == NULL) { /* fragment got swallowed */ 2387 retval = IP_FW_DENY; 2388 } else { /* good, packet complete */ 2389 int hlen; 2390 2391 ip = mtod(m, struct ip *); 2392 hlen = ip->ip_hl << 2; 2393 SET_NET_IPLEN(ip); 2394 ip->ip_sum = 0; 2395 if (hlen == sizeof(struct ip)) 2396 ip->ip_sum = in_cksum_hdr(ip); 2397 else 2398 ip->ip_sum = in_cksum(m, hlen); 2399 retval = IP_FW_REASS; 2400 set_match(args, f_pos, chain); 2401 } 2402 done = 1; /* exit outer loop */ 2403 break; 2404 } 2405 2406 default: 2407 panic("-- unknown opcode %d\n", cmd->opcode); 2408 } /* end of switch() on opcodes */ 2409 /* 2410 * if we get here with l=0, then match is irrelevant. 2411 */ 2412 2413 if (cmd->len & F_NOT) 2414 match = !match; 2415 2416 if (match) { 2417 if (cmd->len & F_OR) 2418 skip_or = 1; 2419 } else { 2420 if (!(cmd->len & F_OR)) /* not an OR block, */ 2421 break; /* try next rule */ 2422 } 2423 2424 } /* end of inner loop, scan opcodes */ 2425#undef PULLUP_LEN 2426 2427 if (done) 2428 break; 2429 2430/* next_rule:; */ /* try next rule */ 2431 2432 } /* end of outer for, scan rules */ 2433 2434 if (done) { 2435 struct ip_fw *rule = chain->map[f_pos]; 2436 /* Update statistics */ 2437 rule->pcnt++; 2438 rule->bcnt += pktlen; 2439 rule->timestamp = time_uptime; 2440 } else { 2441 retval = IP_FW_DENY; 2442 printf("ipfw: ouch!, skip past end of rules, denying packet\n"); 2443 } 2444 IPFW_RUNLOCK(chain); 2445#ifdef __FreeBSD__ 2446 if (ucred_cache != NULL) 2447 crfree(ucred_cache); 2448#endif 2449 return (retval); 2450 2451pullup_failed: 2452 if (V_fw_verbose) 2453 printf("ipfw: pullup failed\n"); 2454 return (IP_FW_DENY); 2455} 2456 2457/* 2458 * Module and VNET glue 2459 */ 2460 2461/* 2462 * Stuff that must be initialised only on boot or module load 2463 */ 2464static int 2465ipfw_init(void) 2466{ 2467 int error = 0; 2468 2469 ipfw_dyn_attach(); 2470 /* 2471 * Only print out this stuff the first time around, 2472 * when called from the sysinit code. 2473 */ 2474 printf("ipfw2 " 2475#ifdef INET6 2476 "(+ipv6) " 2477#endif 2478 "initialized, divert %s, nat %s, " 2479 "rule-based forwarding " 2480#ifdef IPFIREWALL_FORWARD 2481 "enabled, " 2482#else 2483 "disabled, " 2484#endif 2485 "default to %s, logging ", 2486#ifdef IPDIVERT 2487 "enabled", 2488#else 2489 "loadable", 2490#endif 2491#ifdef IPFIREWALL_NAT 2492 "enabled", 2493#else 2494 "loadable", 2495#endif 2496 default_to_accept ? "accept" : "deny"); 2497 2498 /* 2499 * Note: V_xxx variables can be accessed here but the vnet specific 2500 * initializer may not have been called yet for the VIMAGE case. 2501 * Tuneables will have been processed. We will print out values for 2502 * the default vnet. 2503 * XXX This should all be rationalized AFTER 8.0 2504 */ 2505 if (V_fw_verbose == 0) 2506 printf("disabled\n"); 2507 else if (V_verbose_limit == 0) 2508 printf("unlimited\n"); 2509 else 2510 printf("limited to %d packets/entry by default\n", 2511 V_verbose_limit); 2512 2513 ipfw_log_bpf(1); /* init */ 2514 return (error); 2515} 2516 2517/* 2518 * Called for the removal of the last instance only on module unload. 2519 */ 2520static void 2521ipfw_destroy(void) 2522{ 2523 2524 ipfw_log_bpf(0); /* uninit */ 2525 ipfw_dyn_detach(); 2526 printf("IP firewall unloaded\n"); 2527} 2528 2529/* 2530 * Stuff that must be initialized for every instance 2531 * (including the first of course). 2532 */ 2533static int 2534vnet_ipfw_init(const void *unused) 2535{ 2536 int error; 2537 struct ip_fw *rule = NULL; 2538 struct ip_fw_chain *chain; 2539 2540 chain = &V_layer3_chain; 2541 2542 /* First set up some values that are compile time options */ 2543 V_autoinc_step = 100; /* bounded to 1..1000 in add_rule() */ 2544 V_fw_deny_unknown_exthdrs = 1; 2545#ifdef IPFIREWALL_VERBOSE 2546 V_fw_verbose = 1; 2547#endif 2548#ifdef IPFIREWALL_VERBOSE_LIMIT 2549 V_verbose_limit = IPFIREWALL_VERBOSE_LIMIT; 2550#endif 2551#ifdef IPFIREWALL_NAT 2552 LIST_INIT(&chain->nat); 2553#endif 2554 2555 /* insert the default rule and create the initial map */ 2556 chain->n_rules = 1; 2557 chain->static_len = sizeof(struct ip_fw); 2558 chain->map = malloc(sizeof(struct ip_fw *), M_IPFW, M_NOWAIT | M_ZERO); 2559 if (chain->map) 2560 rule = malloc(chain->static_len, M_IPFW, M_NOWAIT | M_ZERO); 2561 if (rule == NULL) { 2562 if (chain->map) 2563 free(chain->map, M_IPFW); 2564 printf("ipfw2: ENOSPC initializing default rule " 2565 "(support disabled)\n"); 2566 return (ENOSPC); 2567 } 2568 error = ipfw_init_tables(chain); 2569 if (error) { 2570 panic("init_tables"); /* XXX Marko fix this ! */ 2571 } 2572 2573 /* fill and insert the default rule */ 2574 rule->act_ofs = 0; 2575 rule->rulenum = IPFW_DEFAULT_RULE; 2576 rule->cmd_len = 1; 2577 rule->set = RESVD_SET; 2578 rule->cmd[0].len = 1; 2579 rule->cmd[0].opcode = default_to_accept ? O_ACCEPT : O_DENY; 2580 chain->rules = chain->default_rule = chain->map[0] = rule; 2581 chain->id = rule->id = 1; 2582 2583 IPFW_LOCK_INIT(chain); 2584 ipfw_dyn_init(); 2585 2586 /* First set up some values that are compile time options */ 2587 V_ipfw_vnet_ready = 1; /* Open for business */ 2588 2589 /* 2590 * Hook the sockopt handler, and the layer2 (V_ip_fw_chk_ptr) 2591 * and pfil hooks for ipv4 and ipv6. Even if the latter two fail 2592 * we still keep the module alive because the sockopt and 2593 * layer2 paths are still useful. 2594 * ipfw[6]_hook return 0 on success, ENOENT on failure, 2595 * so we can ignore the exact return value and just set a flag. 2596 * 2597 * Note that V_fw[6]_enable are manipulated by a SYSCTL_PROC so 2598 * changes in the underlying (per-vnet) variables trigger 2599 * immediate hook()/unhook() calls. 2600 * In layer2 we have the same behaviour, except that V_ether_ipfw 2601 * is checked on each packet because there are no pfil hooks. 2602 */ 2603 V_ip_fw_ctl_ptr = ipfw_ctl; 2604 V_ip_fw_chk_ptr = ipfw_chk; 2605 error = ipfw_attach_hooks(1); 2606 return (error); 2607} 2608 2609/* 2610 * Called for the removal of each instance. 2611 */ 2612static int 2613vnet_ipfw_uninit(const void *unused) 2614{ 2615 struct ip_fw *reap, *rule; 2616 struct ip_fw_chain *chain = &V_layer3_chain; 2617 int i; 2618 2619 V_ipfw_vnet_ready = 0; /* tell new callers to go away */ 2620 /* 2621 * disconnect from ipv4, ipv6, layer2 and sockopt. 2622 * Then grab, release and grab again the WLOCK so we make 2623 * sure the update is propagated and nobody will be in. 2624 */ 2625 (void)ipfw_attach_hooks(0 /* detach */); 2626 V_ip_fw_chk_ptr = NULL; 2627 V_ip_fw_ctl_ptr = NULL; 2628 IPFW_UH_WLOCK(chain); 2629 IPFW_UH_WUNLOCK(chain); 2630 IPFW_UH_WLOCK(chain); 2631 2632 IPFW_WLOCK(chain); 2633 IPFW_WUNLOCK(chain); 2634 IPFW_WLOCK(chain); 2635 2636 ipfw_dyn_uninit(0); /* run the callout_drain */ 2637 ipfw_destroy_tables(chain); 2638 reap = NULL; 2639 for (i = 0; i < chain->n_rules; i++) { 2640 rule = chain->map[i]; 2641 rule->x_next = reap; 2642 reap = rule; 2643 } 2644 if (chain->map) 2645 free(chain->map, M_IPFW); 2646 IPFW_WUNLOCK(chain); 2647 IPFW_UH_WUNLOCK(chain); 2648 if (reap != NULL) 2649 ipfw_reap_rules(reap); 2650 IPFW_LOCK_DESTROY(chain); 2651 ipfw_dyn_uninit(1); /* free the remaining parts */ 2652 return 0; 2653} 2654 2655/* 2656 * Module event handler. 2657 * In general we have the choice of handling most of these events by the 2658 * event handler or by the (VNET_)SYS(UN)INIT handlers. I have chosen to 2659 * use the SYSINIT handlers as they are more capable of expressing the 2660 * flow of control during module and vnet operations, so this is just 2661 * a skeleton. Note there is no SYSINIT equivalent of the module 2662 * SHUTDOWN handler, but we don't have anything to do in that case anyhow. 2663 */ 2664static int 2665ipfw_modevent(module_t mod, int type, void *unused) 2666{ 2667 int err = 0; 2668 2669 switch (type) { 2670 case MOD_LOAD: 2671 /* Called once at module load or 2672 * system boot if compiled in. */ 2673 break; 2674 case MOD_QUIESCE: 2675 /* Called before unload. May veto unloading. */ 2676 break; 2677 case MOD_UNLOAD: 2678 /* Called during unload. */ 2679 break; 2680 case MOD_SHUTDOWN: 2681 /* Called during system shutdown. */ 2682 break; 2683 default: 2684 err = EOPNOTSUPP; 2685 break; 2686 } 2687 return err; 2688} 2689 2690static moduledata_t ipfwmod = { 2691 "ipfw", 2692 ipfw_modevent, 2693 0 2694}; 2695 2696/* Define startup order. */ 2697#define IPFW_SI_SUB_FIREWALL SI_SUB_PROTO_IFATTACHDOMAIN 2698#define IPFW_MODEVENT_ORDER (SI_ORDER_ANY - 255) /* On boot slot in here. */ 2699#define IPFW_MODULE_ORDER (IPFW_MODEVENT_ORDER + 1) /* A little later. */ 2700#define IPFW_VNET_ORDER (IPFW_MODEVENT_ORDER + 2) /* Later still. */ 2701 2702DECLARE_MODULE(ipfw, ipfwmod, IPFW_SI_SUB_FIREWALL, IPFW_MODEVENT_ORDER); 2703MODULE_VERSION(ipfw, 2); 2704/* should declare some dependencies here */ 2705 2706/* 2707 * Starting up. Done in order after ipfwmod() has been called. 2708 * VNET_SYSINIT is also called for each existing vnet and each new vnet. 2709 */ 2710SYSINIT(ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER, 2711 ipfw_init, NULL); 2712VNET_SYSINIT(vnet_ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER, 2713 vnet_ipfw_init, NULL); 2714 2715/* 2716 * Closing up shop. These are done in REVERSE ORDER, but still 2717 * after ipfwmod() has been called. Not called on reboot. 2718 * VNET_SYSUNINIT is also called for each exiting vnet as it exits. 2719 * or when the module is unloaded. 2720 */ 2721SYSUNINIT(ipfw_destroy, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER, 2722 ipfw_destroy, NULL); 2723VNET_SYSUNINIT(vnet_ipfw_uninit, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER, 2724 vnet_ipfw_uninit, NULL); 2725/* end of file */ 2726