sys/netpfil/ipfw/ip_fw2.c

   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("$FreeBSD$");
  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
  41 #include <sys/param.h>
  42 #include <sys/systm.h>
  43 #include <sys/condvar.h>
  44 #include <sys/counter.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/rmlock.h>
  56 #include <sys/socket.h>
  57 #include <sys/socketvar.h>
  58 #include <sys/sysctl.h>
  59 #include <sys/syslog.h>
  60 #include <sys/ucred.h>
  61 #include <net/ethernet.h> /* for ETHERTYPE_IP */
  62 #include <net/if.h>
  63 #include <net/if_var.h>
  64 #include <net/route.h>
  65 #include <net/pfil.h>
  66 #include <net/vnet.h>
  67
  68 #include <netpfil/pf/pf_mtag.h>
  69
  70 #include <netinet/in.h>
  71 #include <netinet/in_var.h>
  72 #include <netinet/in_pcb.h>
  73 #include <netinet/ip.h>
  74 #include <netinet/ip_var.h>
  75 #include <netinet/ip_icmp.h>
  76 #include <netinet/ip_fw.h>
  77 #include <netinet/ip_carp.h>
  78 #include <netinet/pim.h>
  79 #include <netinet/tcp_var.h>
  80 #include <netinet/udp.h>
  81 #include <netinet/udp_var.h>
  82 #include <netinet/sctp.h>
  83
  84 #include <netinet/ip6.h>
  85 #include <netinet/icmp6.h>
  86 #include <netinet/in_fib.h>
  87 #ifdef INET6
  88 #include <netinet6/in6_fib.h>
  89 #include <netinet6/in6_pcb.h>
  90 #include <netinet6/scope6_var.h>
  91 #include <netinet6/ip6_var.h>
  92 #endif
  93
  94 #include <net/if_gre.h> /* for struct grehdr */
  95
  96 #include <netpfil/ipfw/ip_fw_private.h>
  97
  98 #include <machine/in_cksum.h>   /* XXX for in_cksum */
  99
 100 #ifdef MAC
 101 #include <security/mac/mac_framework.h>
 102 #endif
 103
 104 /*
 105  * static variables followed by global ones.
 106  * All ipfw global variables are here.
 107  */
 108
 109 static VNET_DEFINE(int, fw_deny_unknown_exthdrs);
 110 #define V_fw_deny_unknown_exthdrs       VNET(fw_deny_unknown_exthdrs)
 111
 112 static VNET_DEFINE(int, fw_permit_single_frag6) = 1;
 113 #define V_fw_permit_single_frag6        VNET(fw_permit_single_frag6)
 114
 115 #ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
 116 static int default_to_accept = 1;
 117 #else
 118 static int default_to_accept;
 119 #endif
 120
 121 VNET_DEFINE(int, autoinc_step);
 122 VNET_DEFINE(int, fw_one_pass) = 1;
 123
 124 VNET_DEFINE(unsigned int, fw_tables_max);
 125 VNET_DEFINE(unsigned int, fw_tables_sets) = 0;  /* Don't use set-aware tables */
 126 /* Use 128 tables by default */
 127 static unsigned int default_fw_tables = IPFW_TABLES_DEFAULT;
 128
 129 #ifndef LINEAR_SKIPTO
 130 static int jump_fast(struct ip_fw_chain *chain, struct ip_fw *f, int num,
 131     int tablearg, int jump_backwards);
 132 #define JUMP(ch, f, num, targ, back)    jump_fast(ch, f, num, targ, back)
 133 #else
 134 static int jump_linear(struct ip_fw_chain *chain, struct ip_fw *f, int num,
 135     int tablearg, int jump_backwards);
 136 #define JUMP(ch, f, num, targ, back)    jump_linear(ch, f, num, targ, back)
 137 #endif
 138
 139 /*
 140  * Each rule belongs to one of 32 different sets (0..31).
 141  * The variable set_disable contains one bit per set.
 142  * If the bit is set, all rules in the corresponding set
 143  * are disabled. Set RESVD_SET(31) is reserved for the default rule
 144  * and rules that are not deleted by the flush command,
 145  * and CANNOT be disabled.
 146  * Rules in set RESVD_SET can only be deleted individually.
 147  */
 148 VNET_DEFINE(u_int32_t, set_disable);
 149 #define V_set_disable                   VNET(set_disable)
 150
 151 VNET_DEFINE(int, fw_verbose);
 152 /* counter for ipfw_log(NULL...) */
 153 VNET_DEFINE(u_int64_t, norule_counter);
 154 VNET_DEFINE(int, verbose_limit);
 155
 156 /* layer3_chain contains the list of rules for layer 3 */
 157 VNET_DEFINE(struct ip_fw_chain, layer3_chain);
 158
 159 /* ipfw_vnet_ready controls when we are open for business */
 160 VNET_DEFINE(int, ipfw_vnet_ready) = 0;
 161
 162 VNET_DEFINE(int, ipfw_nat_ready) = 0;
 163
 164 ipfw_nat_t *ipfw_nat_ptr = NULL;
 165 struct cfg_nat *(*lookup_nat_ptr)(struct nat_list *, int);
 166 ipfw_nat_cfg_t *ipfw_nat_cfg_ptr;
 167 ipfw_nat_cfg_t *ipfw_nat_del_ptr;
 168 ipfw_nat_cfg_t *ipfw_nat_get_cfg_ptr;
 169 ipfw_nat_cfg_t *ipfw_nat_get_log_ptr;
 170
 171 #ifdef SYSCTL_NODE
 172 uint32_t dummy_def = IPFW_DEFAULT_RULE;
 173 static int sysctl_ipfw_table_num(SYSCTL_HANDLER_ARGS);
 174 static int sysctl_ipfw_tables_sets(SYSCTL_HANDLER_ARGS);
 175
 176 SYSBEGIN(f3)
 177
 178 SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall");
 179 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, one_pass,
 180     CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_one_pass), 0,
 181     "Only do a single pass through ipfw when using dummynet(4)");
 182 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, autoinc_step,
 183     CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(autoinc_step), 0,
 184     "Rule number auto-increment step");
 185 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose,
 186     CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_verbose), 0,
 187     "Log matches to ipfw rules");
 188 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit,
 189     CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(verbose_limit), 0,
 190     "Set upper limit of matches of ipfw rules logged");
 191 SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, default_rule, CTLFLAG_RD,
 192     &dummy_def, 0,
 193     "The default/max possible rule number.");
 194 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, tables_max,
 195     CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW, 0, 0, sysctl_ipfw_table_num, "IU",
 196     "Maximum number of concurrently used tables");
 197 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, tables_sets,
 198     CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW,
 199     0, 0, sysctl_ipfw_tables_sets, "IU",
 200     "Use per-set namespace for tables");
 201 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, default_to_accept, CTLFLAG_RDTUN,
 202     &default_to_accept, 0,
 203     "Make the default rule accept all packets.");
 204 TUNABLE_INT("net.inet.ip.fw.tables_max", (int *)&default_fw_tables);
 205 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, static_count,
 206     CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(layer3_chain.n_rules), 0,
 207     "Number of static rules");
 208
 209 #ifdef INET6
 210 SYSCTL_DECL(_net_inet6_ip6);
 211 SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall");
 212 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, deny_unknown_exthdrs,
 213     CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE,
 214     &VNET_NAME(fw_deny_unknown_exthdrs), 0,
 215     "Deny packets with unknown IPv6 Extension Headers");
 216 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, permit_single_frag6,
 217     CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE,
 218     &VNET_NAME(fw_permit_single_frag6), 0,
 219     "Permit single packet IPv6 fragments");
 220 #endif /* INET6 */
 221
 222 SYSEND
 223
 224 #endif /* SYSCTL_NODE */
 225
 226
 227 /*
 228  * Some macros used in the various matching options.
 229  * L3HDR maps an ipv4 pointer into a layer3 header pointer of type T
 230  * Other macros just cast void * into the appropriate type
 231  */
 232 #define L3HDR(T, ip)    ((T *)((u_int32_t *)(ip) + (ip)->ip_hl))
 233 #define TCP(p)          ((struct tcphdr *)(p))
 234 #define SCTP(p)         ((struct sctphdr *)(p))
 235 #define UDP(p)          ((struct udphdr *)(p))
 236 #define ICMP(p)         ((struct icmphdr *)(p))
 237 #define ICMP6(p)        ((struct icmp6_hdr *)(p))
 238
 239 static __inline int
 240 icmptype_match(struct icmphdr *icmp, ipfw_insn_u32 *cmd)
 241 {
 242         int type = icmp->icmp_type;
 243
 244         return (type <= ICMP_MAXTYPE && (cmd->d[0] & (1<<type)) );
 245 }
 246
 247 #define TT      ( (1 << ICMP_ECHO) | (1 << ICMP_ROUTERSOLICIT) | \
 248     (1 << ICMP_TSTAMP) | (1 << ICMP_IREQ) | (1 << ICMP_MASKREQ) )
 249
 250 static int
 251 is_icmp_query(struct icmphdr *icmp)
 252 {
 253         int type = icmp->icmp_type;
 254
 255         return (type <= ICMP_MAXTYPE && (TT & (1<<type)) );
 256 }
 257 #undef TT
 258
 259 /*
 260  * The following checks use two arrays of 8 or 16 bits to store the
 261  * bits that we want set or clear, respectively. They are in the
 262  * low and high half of cmd->arg1 or cmd->d[0].
 263  *
 264  * We scan options and store the bits we find set. We succeed if
 265  *
 266  *      (want_set & ~bits) == 0 && (want_clear & ~bits) == want_clear
 267  *
 268  * The code is sometimes optimized not to store additional variables.
 269  */
 270
 271 static int
 272 flags_match(ipfw_insn *cmd, u_int8_t bits)
 273 {
 274         u_char want_clear;
 275         bits = ~bits;
 276
 277         if ( ((cmd->arg1 & 0xff) & bits) != 0)
 278                 return 0; /* some bits we want set were clear */
 279         want_clear = (cmd->arg1 >> 8) & 0xff;
 280         if ( (want_clear & bits) != want_clear)
 281                 return 0; /* some bits we want clear were set */
 282         return 1;
 283 }
 284
 285 static int
 286 ipopts_match(struct ip *ip, ipfw_insn *cmd)
 287 {
 288         int optlen, bits = 0;
 289         u_char *cp = (u_char *)(ip + 1);
 290         int x = (ip->ip_hl << 2) - sizeof (struct ip);
 291
 292         for (; x > 0; x -= optlen, cp += optlen) {
 293                 int opt = cp[IPOPT_OPTVAL];
 294
 295                 if (opt == IPOPT_EOL)
 296                         break;
 297                 if (opt == IPOPT_NOP)
 298                         optlen = 1;
 299                 else {
 300                         optlen = cp[IPOPT_OLEN];
 301                         if (optlen <= 0 || optlen > x)
 302                                 return 0; /* invalid or truncated */
 303                 }
 304                 switch (opt) {
 305
 306                 default:
 307                         break;
 308
 309                 case IPOPT_LSRR:
 310                         bits |= IP_FW_IPOPT_LSRR;
 311                         break;
 312
 313                 case IPOPT_SSRR:
 314                         bits |= IP_FW_IPOPT_SSRR;
 315                         break;
 316
 317                 case IPOPT_RR:
 318                         bits |= IP_FW_IPOPT_RR;
 319                         break;
 320
 321                 case IPOPT_TS:
 322                         bits |= IP_FW_IPOPT_TS;
 323                         break;
 324                 }
 325         }
 326         return (flags_match(cmd, bits));
 327 }
 328
 329 static int
 330 tcpopts_match(struct tcphdr *tcp, ipfw_insn *cmd)
 331 {
 332         int optlen, bits = 0;
 333         u_char *cp = (u_char *)(tcp + 1);
 334         int x = (tcp->th_off << 2) - sizeof(struct tcphdr);
 335
 336         for (; x > 0; x -= optlen, cp += optlen) {
 337                 int opt = cp[0];
 338                 if (opt == TCPOPT_EOL)
 339                         break;
 340                 if (opt == TCPOPT_NOP)
 341                         optlen = 1;
 342                 else {
 343                         optlen = cp[1];
 344                         if (optlen <= 0)
 345                                 break;
 346                 }
 347
 348                 switch (opt) {
 349
 350                 default:
 351                         break;
 352
 353                 case TCPOPT_MAXSEG:
 354                         bits |= IP_FW_TCPOPT_MSS;
 355                         break;
 356
 357                 case TCPOPT_WINDOW:
 358                         bits |= IP_FW_TCPOPT_WINDOW;
 359                         break;
 360
 361                 case TCPOPT_SACK_PERMITTED:
 362                 case TCPOPT_SACK:
 363                         bits |= IP_FW_TCPOPT_SACK;
 364                         break;
 365
 366                 case TCPOPT_TIMESTAMP:
 367                         bits |= IP_FW_TCPOPT_TS;
 368                         break;
 369
 370                 }
 371         }
 372         return (flags_match(cmd, bits));
 373 }
 374
 375 static int
 376 iface_match(struct ifnet *ifp, ipfw_insn_if *cmd, struct ip_fw_chain *chain,
 377     uint32_t *tablearg)
 378 {
 379
 380         if (ifp == NULL)        /* no iface with this packet, match fails */
 381                 return (0);
 382
 383         /* Check by name or by IP address */
 384         if (cmd->name[0] != '\0') { /* match by name */
 385                 if (cmd->name[0] == '\1') /* use tablearg to match */
 386                         return ipfw_lookup_table(chain, cmd->p.kidx, 0,
 387                             &ifp->if_index, tablearg);
 388                 /* Check name */
 389                 if (cmd->p.glob) {
 390                         if (fnmatch(cmd->name, ifp->if_xname, 0) == 0)
 391                                 return(1);
 392                 } else {
 393                         if (strncmp(ifp->if_xname, cmd->name, IFNAMSIZ) == 0)
 394                                 return(1);
 395                 }
 396         } else {
 397 #if !defined(USERSPACE) && defined(__FreeBSD__) /* and OSX too ? */
 398                 struct ifaddr *ia;
 399
 400                 if_addr_rlock(ifp);
 401                 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) {
 402                         if (ia->ifa_addr->sa_family != AF_INET)
 403                                 continue;
 404                         if (cmd->p.ip.s_addr == ((struct sockaddr_in *)
 405                             (ia->ifa_addr))->sin_addr.s_addr) {
 406                                 if_addr_runlock(ifp);
 407                                 return(1);      /* match */
 408                         }
 409                 }
 410                 if_addr_runlock(ifp);
 411 #endif /* __FreeBSD__ */
 412         }
 413         return(0);      /* no match, fail ... */
 414 }
 415
 416 /*
 417  * The verify_path function checks if a route to the src exists and
 418  * if it is reachable via ifp (when provided).
 419  *
 420  * The 'verrevpath' option checks that the interface that an IP packet
 421  * arrives on is the same interface that traffic destined for the
 422  * packet's source address would be routed out of.
 423  * The 'versrcreach' option just checks that the source address is
 424  * reachable via any route (except default) in the routing table.
 425  * These two are a measure to block forged packets. This is also
 426  * commonly known as "anti-spoofing" or Unicast Reverse Path
 427  * Forwarding (Unicast RFP) in Cisco-ese. The name of the knobs
 428  * is purposely reminiscent of the Cisco IOS command,
 429  *
 430  *   ip verify unicast reverse-path
 431  *   ip verify unicast source reachable-via any
 432  *
 433  * which implements the same functionality. But note that the syntax
 434  * is misleading, and the check may be performed on all IP packets
 435  * whether unicast, multicast, or broadcast.
 436  */
 437 static int
 438 verify_path(struct in_addr src, struct ifnet *ifp, u_int fib)
 439 {
 440 #if defined(USERSPACE) || !defined(__FreeBSD__)
 441         return 0;
 442 #else
 443         struct nhop4_basic nh4;
 444
 445         if (fib4_lookup_nh_basic(fib, src, NHR_IFAIF, 0, &nh4) != 0)
 446                 return (0);
 447
 448         /*
 449          * If ifp is provided, check for equality with rtentry.
 450          * We should use rt->rt_ifa->ifa_ifp, instead of rt->rt_ifp,
 451          * in order to pass packets injected back by if_simloop():
 452          * routing entry (via lo0) for our own address
 453          * may exist, so we need to handle routing assymetry.
 454          */
 455         if (ifp != NULL && ifp != nh4.nh_ifp)
 456                 return (0);
 457
 458         /* if no ifp provided, check if rtentry is not default route */
 459         if (ifp == NULL && (nh4.nh_flags & NHF_DEFAULT) != 0)
 460                 return (0);
 461
 462         /* or if this is a blackhole/reject route */
 463         if (ifp == NULL && (nh4.nh_flags & (NHF_REJECT|NHF_BLACKHOLE)) != 0)
 464                 return (0);
 465
 466         /* found valid route */
 467         return 1;
 468 #endif /* __FreeBSD__ */
 469 }
 470
 471 #ifdef INET6
 472 /*
 473  * ipv6 specific rules here...
 474  */
 475 static __inline int
 476 icmp6type_match (int type, ipfw_insn_u32 *cmd)
 477 {
 478         return (type <= ICMP6_MAXTYPE && (cmd->d[type/32] & (1<<(type%32)) ) );
 479 }
 480
 481 static int
 482 flow6id_match( int curr_flow, ipfw_insn_u32 *cmd )
 483 {
 484         int i;
 485         for (i=0; i <= cmd->o.arg1; ++i )
 486                 if (curr_flow == cmd->d[i] )
 487                         return 1;
 488         return 0;
 489 }
 490
 491 /* support for IP6_*_ME opcodes */
 492 static const struct in6_addr lla_mask = {{{
 493         0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff,
 494         0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
 495 }}};
 496
 497 static int
 498 ipfw_localip6(struct in6_addr *in6)
 499 {
 500         struct rm_priotracker in6_ifa_tracker;
 501         struct in6_ifaddr *ia;
 502
 503         if (IN6_IS_ADDR_MULTICAST(in6))
 504                 return (0);
 505
 506         if (!IN6_IS_ADDR_LINKLOCAL(in6))
 507                 return (in6_localip(in6));
 508
 509         IN6_IFADDR_RLOCK(&in6_ifa_tracker);
 510         TAILQ_FOREACH(ia, &V_in6_ifaddrhead, ia_link) {
 511                 if (!IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr))
 512                         continue;
 513                 if (IN6_ARE_MASKED_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
 514                     in6, &lla_mask)) {
 515                         IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
 516                         return (1);
 517                 }
 518         }
 519         IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
 520         return (0);
 521 }
 522
 523 static int
 524 verify_path6(struct in6_addr *src, struct ifnet *ifp, u_int fib)
 525 {
 526         struct nhop6_basic nh6;
 527
 528         if (IN6_IS_SCOPE_LINKLOCAL(src))
 529                 return (1);
 530
 531         if (fib6_lookup_nh_basic(fib, src, 0, NHR_IFAIF, 0, &nh6) != 0)
 532                 return (0);
 533
 534         /* If ifp is provided, check for equality with route table. */
 535         if (ifp != NULL && ifp != nh6.nh_ifp)
 536                 return (0);
 537
 538         /* if no ifp provided, check if rtentry is not default route */
 539         if (ifp == NULL && (nh6.nh_flags & NHF_DEFAULT) != 0)
 540                 return (0);
 541
 542         /* or if this is a blackhole/reject route */
 543         if (ifp == NULL && (nh6.nh_flags & (NHF_REJECT|NHF_BLACKHOLE)) != 0)
 544                 return (0);
 545
 546         /* found valid route */
 547         return 1;
 548 }
 549
 550 static int
 551 is_icmp6_query(int icmp6_type)
 552 {
 553         if ((icmp6_type <= ICMP6_MAXTYPE) &&
 554             (icmp6_type == ICMP6_ECHO_REQUEST ||
 555             icmp6_type == ICMP6_MEMBERSHIP_QUERY ||
 556             icmp6_type == ICMP6_WRUREQUEST ||
 557             icmp6_type == ICMP6_FQDN_QUERY ||
 558             icmp6_type == ICMP6_NI_QUERY))
 559                 return (1);
 560
 561         return (0);
 562 }
 563
 564 static void
 565 send_reject6(struct ip_fw_args *args, int code, u_int hlen, struct ip6_hdr *ip6)
 566 {
 567         struct mbuf *m;
 568
 569         m = args->m;
 570         if (code == ICMP6_UNREACH_RST && args->f_id.proto == IPPROTO_TCP) {
 571                 struct tcphdr *tcp;
 572                 tcp = (struct tcphdr *)((char *)ip6 + hlen);
 573
 574                 if ((tcp->th_flags & TH_RST) == 0) {
 575                         struct mbuf *m0;
 576                         m0 = ipfw_send_pkt(args->m, &(args->f_id),
 577                             ntohl(tcp->th_seq), ntohl(tcp->th_ack),
 578                             tcp->th_flags | TH_RST);
 579                         if (m0 != NULL)
 580                                 ip6_output(m0, NULL, NULL, 0, NULL, NULL,
 581                                     NULL);
 582                 }
 583                 FREE_PKT(m);
 584         } else if (code != ICMP6_UNREACH_RST) { /* Send an ICMPv6 unreach. */
 585 #if 0
 586                 /*
 587                  * Unlike above, the mbufs need to line up with the ip6 hdr,
 588                  * as the contents are read. We need to m_adj() the
 589                  * needed amount.
 590                  * The mbuf will however be thrown away so we can adjust it.
 591                  * Remember we did an m_pullup on it already so we
 592                  * can make some assumptions about contiguousness.
 593                  */
 594                 if (args->L3offset)
 595                         m_adj(m, args->L3offset);
 596 #endif
 597                 icmp6_error(m, ICMP6_DST_UNREACH, code, 0);
 598         } else
 599                 FREE_PKT(m);
 600
 601         args->m = NULL;
 602 }
 603
 604 #endif /* INET6 */
 605
 606
 607 /*
 608  * sends a reject message, consuming the mbuf passed as an argument.
 609  */
 610 static void
 611 send_reject(struct ip_fw_args *args, int code, int iplen, struct ip *ip)
 612 {
 613
 614 #if 0
 615         /* XXX When ip is not guaranteed to be at mtod() we will
 616          * need to account for this */
 617          * The mbuf will however be thrown away so we can adjust it.
 618          * Remember we did an m_pullup on it already so we
 619          * can make some assumptions about contiguousness.
 620          */
 621         if (args->L3offset)
 622                 m_adj(m, args->L3offset);
 623 #endif
 624         if (code != ICMP_REJECT_RST) { /* Send an ICMP unreach */
 625                 icmp_error(args->m, ICMP_UNREACH, code, 0L, 0);
 626         } else if (args->f_id.proto == IPPROTO_TCP) {
 627                 struct tcphdr *const tcp =
 628                     L3HDR(struct tcphdr, mtod(args->m, struct ip *));
 629                 if ( (tcp->th_flags & TH_RST) == 0) {
 630                         struct mbuf *m;
 631                         m = ipfw_send_pkt(args->m, &(args->f_id),
 632                                 ntohl(tcp->th_seq), ntohl(tcp->th_ack),
 633                                 tcp->th_flags | TH_RST);
 634                         if (m != NULL)
 635                                 ip_output(m, NULL, NULL, 0, NULL, NULL);
 636                 }
 637                 FREE_PKT(args->m);
 638         } else
 639                 FREE_PKT(args->m);
 640         args->m = NULL;
 641 }
 642
 643 /*
 644  * Support for uid/gid/jail lookup. These tests are expensive
 645  * (because we may need to look into the list of active sockets)
 646  * so we cache the results. ugid_lookupp is 0 if we have not
 647  * yet done a lookup, 1 if we succeeded, and -1 if we tried
 648  * and failed. The function always returns the match value.
 649  * We could actually spare the variable and use *uc, setting
 650  * it to '(void *)check_uidgid if we have no info, NULL if
 651  * we tried and failed, or any other value if successful.
 652  */
 653 static int
 654 check_uidgid(ipfw_insn_u32 *insn, struct ip_fw_args *args, int *ugid_lookupp,
 655     struct ucred **uc)
 656 {
 657 #if defined(USERSPACE)
 658         return 0;       // not supported in userspace
 659 #else
 660 #ifndef __FreeBSD__
 661         /* XXX */
 662         return cred_check(insn, proto, oif,
 663             dst_ip, dst_port, src_ip, src_port,
 664             (struct bsd_ucred *)uc, ugid_lookupp, ((struct mbuf *)inp)->m_skb);
 665 #else  /* FreeBSD */
 666         struct in_addr src_ip, dst_ip;
 667         struct inpcbinfo *pi;
 668         struct ipfw_flow_id *id;
 669         struct inpcb *pcb, *inp;
 670         struct ifnet *oif;
 671         int lookupflags;
 672         int match;
 673
 674         id = &args->f_id;
 675         inp = args->inp;
 676         oif = args->oif;
 677
 678         /*
 679          * Check to see if the UDP or TCP stack supplied us with
 680          * the PCB. If so, rather then holding a lock and looking
 681          * up the PCB, we can use the one that was supplied.
 682          */
 683         if (inp && *ugid_lookupp == 0) {
 684                 INP_LOCK_ASSERT(inp);
 685                 if (inp->inp_socket != NULL) {
 686                         *uc = crhold(inp->inp_cred);
 687                         *ugid_lookupp = 1;
 688                 } else
 689                         *ugid_lookupp = -1;
 690         }
 691         /*
 692          * If we have already been here and the packet has no
 693          * PCB entry associated with it, then we can safely
 694          * assume that this is a no match.
 695          */
 696         if (*ugid_lookupp == -1)
 697                 return (0);
 698         if (id->proto == IPPROTO_TCP) {
 699                 lookupflags = 0;
 700                 pi = &V_tcbinfo;
 701         } else if (id->proto == IPPROTO_UDP) {
 702                 lookupflags = INPLOOKUP_WILDCARD;
 703                 pi = &V_udbinfo;
 704         } else
 705                 return 0;
 706         lookupflags |= INPLOOKUP_RLOCKPCB;
 707         match = 0;
 708         if (*ugid_lookupp == 0) {
 709                 if (id->addr_type == 6) {
 710 #ifdef INET6
 711                         if (oif == NULL)
 712                                 pcb = in6_pcblookup_mbuf(pi,
 713                                     &id->src_ip6, htons(id->src_port),
 714                                     &id->dst_ip6, htons(id->dst_port),
 715                                     lookupflags, oif, args->m);
 716                         else
 717                                 pcb = in6_pcblookup_mbuf(pi,
 718                                     &id->dst_ip6, htons(id->dst_port),
 719                                     &id->src_ip6, htons(id->src_port),
 720                                     lookupflags, oif, args->m);
 721 #else
 722                         *ugid_lookupp = -1;
 723                         return (0);
 724 #endif
 725                 } else {
 726                         src_ip.s_addr = htonl(id->src_ip);
 727                         dst_ip.s_addr = htonl(id->dst_ip);
 728                         if (oif == NULL)
 729                                 pcb = in_pcblookup_mbuf(pi,
 730                                     src_ip, htons(id->src_port),
 731                                     dst_ip, htons(id->dst_port),
 732                                     lookupflags, oif, args->m);
 733                         else
 734                                 pcb = in_pcblookup_mbuf(pi,
 735                                     dst_ip, htons(id->dst_port),
 736                                     src_ip, htons(id->src_port),
 737                                     lookupflags, oif, args->m);
 738                 }
 739                 if (pcb != NULL) {
 740                         INP_RLOCK_ASSERT(pcb);
 741                         *uc = crhold(pcb->inp_cred);
 742                         *ugid_lookupp = 1;
 743                         INP_RUNLOCK(pcb);
 744                 }
 745                 if (*ugid_lookupp == 0) {
 746                         /*
 747                          * We tried and failed, set the variable to -1
 748                          * so we will not try again on this packet.
 749                          */
 750                         *ugid_lookupp = -1;
 751                         return (0);
 752                 }
 753         }
 754         if (insn->o.opcode == O_UID)
 755                 match = ((*uc)->cr_uid == (uid_t)insn->d[0]);
 756         else if (insn->o.opcode == O_GID)
 757                 match = groupmember((gid_t)insn->d[0], *uc);
 758         else if (insn->o.opcode == O_JAIL)
 759                 match = ((*uc)->cr_prison->pr_id == (int)insn->d[0]);
 760         return (match);
 761 #endif /* __FreeBSD__ */
 762 #endif /* not supported in userspace */
 763 }
 764
 765 /*
 766  * Helper function to set args with info on the rule after the matching
 767  * one. slot is precise, whereas we guess rule_id as they are
 768  * assigned sequentially.
 769  */
 770 static inline void
 771 set_match(struct ip_fw_args *args, int slot,
 772         struct ip_fw_chain *chain)
 773 {
 774         args->rule.chain_id = chain->id;
 775         args->rule.slot = slot + 1; /* we use 0 as a marker */
 776         args->rule.rule_id = 1 + chain->map[slot]->id;
 777         args->rule.rulenum = chain->map[slot]->rulenum;
 778 }
 779
 780 #ifndef LINEAR_SKIPTO
 781 /*
 782  * Helper function to enable cached rule lookups using
 783  * cached_id and cached_pos fields in ipfw rule.
 784  */
 785 static int
 786 jump_fast(struct ip_fw_chain *chain, struct ip_fw *f, int num,
 787     int tablearg, int jump_backwards)
 788 {
 789         int f_pos;
 790
 791         /* If possible use cached f_pos (in f->cached_pos),
 792          * whose version is written in f->cached_id
 793          * (horrible hacks to avoid changing the ABI).
 794          */
 795         if (num != IP_FW_TARG && f->cached_id == chain->id)
 796                 f_pos = f->cached_pos;
 797         else {
 798                 int i = IP_FW_ARG_TABLEARG(chain, num, skipto);
 799                 /* make sure we do not jump backward */
 800                 if (jump_backwards == 0 && i <= f->rulenum)
 801                         i = f->rulenum + 1;
 802                 if (chain->idxmap != NULL)
 803                         f_pos = chain->idxmap[i];
 804                 else
 805                         f_pos = ipfw_find_rule(chain, i, 0);
 806                 /* update the cache */
 807                 if (num != IP_FW_TARG) {
 808                         f->cached_id = chain->id;
 809                         f->cached_pos = f_pos;
 810                 }
 811         }
 812
 813         return (f_pos);
 814 }
 815 #else
 816 /*
 817  * Helper function to enable real fast rule lookups.
 818  */
 819 static int
 820 jump_linear(struct ip_fw_chain *chain, struct ip_fw *f, int num,
 821     int tablearg, int jump_backwards)
 822 {
 823         int f_pos;
 824
 825         num = IP_FW_ARG_TABLEARG(chain, num, skipto);
 826         /* make sure we do not jump backward */
 827         if (jump_backwards == 0 && num <= f->rulenum)
 828                 num = f->rulenum + 1;
 829         f_pos = chain->idxmap[num];
 830
 831         return (f_pos);
 832 }
 833 #endif
 834
 835 #define TARG(k, f)      IP_FW_ARG_TABLEARG(chain, k, f)
 836 /*
 837  * The main check routine for the firewall.
 838  *
 839  * All arguments are in args so we can modify them and return them
 840  * back to the caller.
 841  *
 842  * Parameters:
 843  *
 844  *      args->m (in/out) The packet; we set to NULL when/if we nuke it.
 845  *              Starts with the IP header.
 846  *      args->eh (in)   Mac header if present, NULL for layer3 packet.
 847  *      args->L3offset  Number of bytes bypassed if we came from L2.
 848  *                      e.g. often sizeof(eh)  ** NOTYET **
 849  *      args->oif       Outgoing interface, NULL if packet is incoming.
 850  *              The incoming interface is in the mbuf. (in)
 851  *      args->divert_rule (in/out)
 852  *              Skip up to the first rule past this rule number;
 853  *              upon return, non-zero port number for divert or tee.
 854  *
 855  *      args->rule      Pointer to the last matching rule (in/out)
 856  *      args->next_hop  Socket we are forwarding to (out).
 857  *      args->next_hop6 IPv6 next hop we are forwarding to (out).
 858  *      args->f_id      Addresses grabbed from the packet (out)
 859  *      args->rule.info a cookie depending on rule action
 860  *
 861  * Return value:
 862  *
 863  *      IP_FW_PASS      the packet must be accepted
 864  *      IP_FW_DENY      the packet must be dropped
 865  *      IP_FW_DIVERT    divert packet, port in m_tag
 866  *      IP_FW_TEE       tee packet, port in m_tag
 867  *      IP_FW_DUMMYNET  to dummynet, pipe in args->cookie
 868  *      IP_FW_NETGRAPH  into netgraph, cookie args->cookie
 869  *              args->rule contains the matching rule,
 870  *              args->rule.info has additional information.
 871  *
 872  */
 873 int
 874 ipfw_chk(struct ip_fw_args *args)
 875 {
 876
 877         /*
 878          * Local variables holding state while processing a packet:
 879          *
 880          * IMPORTANT NOTE: to speed up the processing of rules, there
 881          * are some assumption on the values of the variables, which
 882          * are documented here. Should you change them, please check
 883          * the implementation of the various instructions to make sure
 884          * that they still work.
 885          *
 886          * args->eh     The MAC header. It is non-null for a layer2
 887          *      packet, it is NULL for a layer-3 packet.
 888          * **notyet**
 889          * args->L3offset Offset in the packet to the L3 (IP or equiv.) header.
 890          *
 891          * m | args->m  Pointer to the mbuf, as received from the caller.
 892          *      It may change if ipfw_chk() does an m_pullup, or if it
 893          *      consumes the packet because it calls send_reject().
 894          *      XXX This has to change, so that ipfw_chk() never modifies
 895          *      or consumes the buffer.
 896          * ip   is the beginning of the ip(4 or 6) header.
 897          *      Calculated by adding the L3offset to the start of data.
 898          *      (Until we start using L3offset, the packet is
 899          *      supposed to start with the ip header).
 900          */
 901         struct mbuf *m = args->m;
 902         struct ip *ip = mtod(m, struct ip *);
 903
 904         /*
 905          * For rules which contain uid/gid or jail constraints, cache
 906          * a copy of the users credentials after the pcb lookup has been
 907          * executed. This will speed up the processing of rules with
 908          * these types of constraints, as well as decrease contention
 909          * on pcb related locks.
 910          */
 911 #ifndef __FreeBSD__
 912         struct bsd_ucred ucred_cache;
 913 #else
 914         struct ucred *ucred_cache = NULL;
 915 #endif
 916         int ucred_lookup = 0;
 917
 918         /*
 919          * oif | args->oif      If NULL, ipfw_chk has been called on the
 920          *      inbound path (ether_input, ip_input).
 921          *      If non-NULL, ipfw_chk has been called on the outbound path
 922          *      (ether_output, ip_output).
 923          */
 924         struct ifnet *oif = args->oif;
 925
 926         int f_pos = 0;          /* index of current rule in the array */
 927         int retval = 0;
 928
 929         /*
 930          * hlen The length of the IP header.
 931          */
 932         u_int hlen = 0;         /* hlen >0 means we have an IP pkt */
 933
 934         /*
 935          * offset       The offset of a fragment. offset != 0 means that
 936          *      we have a fragment at this offset of an IPv4 packet.
 937          *      offset == 0 means that (if this is an IPv4 packet)
 938          *      this is the first or only fragment.
 939          *      For IPv6 offset|ip6f_mf == 0 means there is no Fragment Header
 940          *      or there is a single packet fragment (fragment header added
 941          *      without needed).  We will treat a single packet fragment as if
 942          *      there was no fragment header (or log/block depending on the
 943          *      V_fw_permit_single_frag6 sysctl setting).
 944          */
 945         u_short offset = 0;
 946         u_short ip6f_mf = 0;
 947
 948         /*
 949          * Local copies of addresses. They are only valid if we have
 950          * an IP packet.
 951          *
 952          * proto        The protocol. Set to 0 for non-ip packets,
 953          *      or to the protocol read from the packet otherwise.
 954          *      proto != 0 means that we have an IPv4 packet.
 955          *
 956          * src_port, dst_port   port numbers, in HOST format. Only
 957          *      valid for TCP and UDP packets.
 958          *
 959          * src_ip, dst_ip       ip addresses, in NETWORK format.
 960          *      Only valid for IPv4 packets.
 961          */
 962         uint8_t proto;
 963         uint16_t src_port = 0, dst_port = 0;    /* NOTE: host format    */
 964         struct in_addr src_ip, dst_ip;          /* NOTE: network format */
 965         int iplen = 0;
 966         int pktlen;
 967         uint16_t        etype = 0;      /* Host order stored ether type */
 968
 969         /*
 970          * dyn_dir = MATCH_UNKNOWN when rules unchecked,
 971          *      MATCH_NONE when checked and not matched (q = NULL),
 972          *      MATCH_FORWARD or MATCH_REVERSE otherwise (q != NULL)
 973          */
 974         int dyn_dir = MATCH_UNKNOWN;
 975         uint16_t dyn_name = 0;
 976         ipfw_dyn_rule *q = NULL;
 977         struct ip_fw_chain *chain = &V_layer3_chain;
 978
 979         /*
 980          * We store in ulp a pointer to the upper layer protocol header.
 981          * In the ipv4 case this is easy to determine from the header,
 982          * but for ipv6 we might have some additional headers in the middle.
 983          * ulp is NULL if not found.
 984          */
 985         void *ulp = NULL;               /* upper layer protocol pointer. */
 986
 987         /* XXX ipv6 variables */
 988         int is_ipv6 = 0;
 989         uint8_t icmp6_type = 0;
 990         uint16_t ext_hd = 0;    /* bits vector for extension header filtering */
 991         /* end of ipv6 variables */
 992
 993         int is_ipv4 = 0;
 994
 995         int done = 0;           /* flag to exit the outer loop */
 996
 997         if (m->m_flags & M_SKIP_FIREWALL || (! V_ipfw_vnet_ready))
 998                 return (IP_FW_PASS);    /* accept */
 999
1000         dst_ip.s_addr = 0;              /* make sure it is initialized */
1001         src_ip.s_addr = 0;              /* make sure it is initialized */
1002         pktlen = m->m_pkthdr.len;
1003         args->f_id.fib = M_GETFIB(m); /* note mbuf not altered) */
1004         proto = args->f_id.proto = 0;   /* mark f_id invalid */
1005                 /* XXX 0 is a valid proto: IP/IPv6 Hop-by-Hop Option */
1006
1007 /*
1008  * PULLUP_TO(len, p, T) makes sure that len + sizeof(T) is contiguous,
1009  * then it sets p to point at the offset "len" in the mbuf. WARNING: the
1010  * pointer might become stale after other pullups (but we never use it
1011  * this way).
1012  */
1013 #define PULLUP_TO(_len, p, T)   PULLUP_LEN(_len, p, sizeof(T))
1014 #define PULLUP_LEN(_len, p, T)                                  \
1015 do {                                                            \
1016         int x = (_len) + T;                                     \
1017         if ((m)->m_len < x) {                                   \
1018                 args->m = m = m_pullup(m, x);                   \
1019                 if (m == NULL)                                  \
1020                         goto pullup_failed;                     \
1021         }                                                       \
1022         p = (mtod(m, char *) + (_len));                         \
1023 } while (0)
1024
1025         /*
1026          * if we have an ether header,
1027          */
1028         if (args->eh)
1029                 etype = ntohs(args->eh->ether_type);
1030
1031         /* Identify IP packets and fill up variables. */
1032         if (pktlen >= sizeof(struct ip6_hdr) &&
1033             (args->eh == NULL || etype == ETHERTYPE_IPV6) && ip->ip_v == 6) {
1034                 struct ip6_hdr *ip6 = (struct ip6_hdr *)ip;
1035                 is_ipv6 = 1;
1036                 args->f_id.addr_type = 6;
1037                 hlen = sizeof(struct ip6_hdr);
1038                 proto = ip6->ip6_nxt;
1039
1040                 /* Search extension headers to find upper layer protocols */
1041                 while (ulp == NULL && offset == 0) {
1042                         switch (proto) {
1043                         case IPPROTO_ICMPV6:
1044                                 PULLUP_TO(hlen, ulp, struct icmp6_hdr);
1045                                 icmp6_type = ICMP6(ulp)->icmp6_type;
1046                                 break;
1047
1048                         case IPPROTO_TCP:
1049                                 PULLUP_TO(hlen, ulp, struct tcphdr);
1050                                 dst_port = TCP(ulp)->th_dport;
1051                                 src_port = TCP(ulp)->th_sport;
1052                                 /* save flags for dynamic rules */
1053                                 args->f_id._flags = TCP(ulp)->th_flags;
1054                                 break;
1055
1056                         case IPPROTO_SCTP:
1057                                 PULLUP_TO(hlen, ulp, struct sctphdr);
1058                                 src_port = SCTP(ulp)->src_port;
1059                                 dst_port = SCTP(ulp)->dest_port;
1060                                 break;
1061
1062                         case IPPROTO_UDP:
1063                                 PULLUP_TO(hlen, ulp, struct udphdr);
1064                                 dst_port = UDP(ulp)->uh_dport;
1065                                 src_port = UDP(ulp)->uh_sport;
1066                                 break;
1067
1068                         case IPPROTO_HOPOPTS:   /* RFC 2460 */
1069                                 PULLUP_TO(hlen, ulp, struct ip6_hbh);
1070                                 ext_hd |= EXT_HOPOPTS;
1071                                 hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3;
1072                                 proto = ((struct ip6_hbh *)ulp)->ip6h_nxt;
1073                                 ulp = NULL;
1074                                 break;
1075
1076                         case IPPROTO_ROUTING:   /* RFC 2460 */
1077                                 PULLUP_TO(hlen, ulp, struct ip6_rthdr);
1078                                 switch (((struct ip6_rthdr *)ulp)->ip6r_type) {
1079                                 case 0:
1080                                         ext_hd |= EXT_RTHDR0;
1081                                         break;
1082                                 case 2:
1083                                         ext_hd |= EXT_RTHDR2;
1084                                         break;
1085                                 default:
1086                                         if (V_fw_verbose)
1087                                                 printf("IPFW2: IPV6 - Unknown "
1088                                                     "Routing Header type(%d)\n",
1089                                                     ((struct ip6_rthdr *)
1090                                                     ulp)->ip6r_type);
1091                                         if (V_fw_deny_unknown_exthdrs)
1092                                             return (IP_FW_DENY);
1093                                         break;
1094                                 }
1095                                 ext_hd |= EXT_ROUTING;
1096                                 hlen += (((struct ip6_rthdr *)ulp)->ip6r_len + 1) << 3;
1097                                 proto = ((struct ip6_rthdr *)ulp)->ip6r_nxt;
1098                                 ulp = NULL;
1099                                 break;
1100
1101                         case IPPROTO_FRAGMENT:  /* RFC 2460 */
1102                                 PULLUP_TO(hlen, ulp, struct ip6_frag);
1103                                 ext_hd |= EXT_FRAGMENT;
1104                                 hlen += sizeof (struct ip6_frag);
1105                                 proto = ((struct ip6_frag *)ulp)->ip6f_nxt;
1106                                 offset = ((struct ip6_frag *)ulp)->ip6f_offlg &
1107                                         IP6F_OFF_MASK;
1108                                 ip6f_mf = ((struct ip6_frag *)ulp)->ip6f_offlg &
1109                                         IP6F_MORE_FRAG;
1110                                 if (V_fw_permit_single_frag6 == 0 &&
1111                                     offset == 0 && ip6f_mf == 0) {
1112                                         if (V_fw_verbose)
1113                                                 printf("IPFW2: IPV6 - Invalid "
1114                                                     "Fragment Header\n");
1115                                         if (V_fw_deny_unknown_exthdrs)
1116                                             return (IP_FW_DENY);
1117                                         break;
1118                                 }
1119                                 args->f_id.extra =
1120                                     ntohl(((struct ip6_frag *)ulp)->ip6f_ident);
1121                                 ulp = NULL;
1122                                 break;
1123
1124                         case IPPROTO_DSTOPTS:   /* RFC 2460 */
1125                                 PULLUP_TO(hlen, ulp, struct ip6_hbh);
1126                                 ext_hd |= EXT_DSTOPTS;
1127                                 hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3;
1128                                 proto = ((struct ip6_hbh *)ulp)->ip6h_nxt;
1129                                 ulp = NULL;
1130                                 break;
1131
1132                         case IPPROTO_AH:        /* RFC 2402 */
1133                                 PULLUP_TO(hlen, ulp, struct ip6_ext);
1134                                 ext_hd |= EXT_AH;
1135                                 hlen += (((struct ip6_ext *)ulp)->ip6e_len + 2) << 2;
1136                                 proto = ((struct ip6_ext *)ulp)->ip6e_nxt;
1137                                 ulp = NULL;
1138                                 break;
1139
1140                         case IPPROTO_ESP:       /* RFC 2406 */
1141                                 PULLUP_TO(hlen, ulp, uint32_t); /* SPI, Seq# */
1142                                 /* Anything past Seq# is variable length and
1143                                  * data past this ext. header is encrypted. */
1144                                 ext_hd |= EXT_ESP;
1145                                 break;
1146
1147                         case IPPROTO_NONE:      /* RFC 2460 */
1148                                 /*
1149                                  * Packet ends here, and IPv6 header has
1150                                  * already been pulled up. If ip6e_len!=0
1151                                  * then octets must be ignored.
1152                                  */
1153                                 ulp = ip; /* non-NULL to get out of loop. */
1154                                 break;
1155
1156                         case IPPROTO_OSPFIGP:
1157                                 /* XXX OSPF header check? */
1158                                 PULLUP_TO(hlen, ulp, struct ip6_ext);
1159                                 break;
1160
1161                         case IPPROTO_PIM:
1162                                 /* XXX PIM header check? */
1163                                 PULLUP_TO(hlen, ulp, struct pim);
1164                                 break;
1165
1166                         case IPPROTO_GRE:       /* RFC 1701 */
1167                                 /* XXX GRE header check? */
1168                                 PULLUP_TO(hlen, ulp, struct grehdr);
1169                                 break;
1170
1171                         case IPPROTO_CARP:
1172                                 PULLUP_TO(hlen, ulp, struct carp_header);
1173                                 if (((struct carp_header *)ulp)->carp_version !=
1174                                     CARP_VERSION)
1175                                         return (IP_FW_DENY);
1176                                 if (((struct carp_header *)ulp)->carp_type !=
1177                                     CARP_ADVERTISEMENT)
1178                                         return (IP_FW_DENY);
1179                                 break;
1180
1181                         case IPPROTO_IPV6:      /* RFC 2893 */
1182                                 PULLUP_TO(hlen, ulp, struct ip6_hdr);
1183                                 break;
1184
1185                         case IPPROTO_IPV4:      /* RFC 2893 */
1186                                 PULLUP_TO(hlen, ulp, struct ip);
1187                                 break;
1188
1189                         default:
1190                                 if (V_fw_verbose)
1191                                         printf("IPFW2: IPV6 - Unknown "
1192                                             "Extension Header(%d), ext_hd=%x\n",
1193                                              proto, ext_hd);
1194                                 if (V_fw_deny_unknown_exthdrs)
1195                                     return (IP_FW_DENY);
1196                                 PULLUP_TO(hlen, ulp, struct ip6_ext);
1197                                 break;
1198                         } /*switch */
1199                 }
1200                 ip = mtod(m, struct ip *);
1201                 ip6 = (struct ip6_hdr *)ip;
1202                 args->f_id.src_ip6 = ip6->ip6_src;
1203                 args->f_id.dst_ip6 = ip6->ip6_dst;
1204                 args->f_id.src_ip = 0;
1205                 args->f_id.dst_ip = 0;
1206                 args->f_id.flow_id6 = ntohl(ip6->ip6_flow);
1207                 iplen = ntohs(ip6->ip6_plen) + sizeof(*ip6);
1208         } else if (pktlen >= sizeof(struct ip) &&
1209             (args->eh == NULL || etype == ETHERTYPE_IP) && ip->ip_v == 4) {
1210                 is_ipv4 = 1;
1211                 hlen = ip->ip_hl << 2;
1212                 args->f_id.addr_type = 4;
1213
1214                 /*
1215                  * Collect parameters into local variables for faster matching.
1216                  */
1217                 proto = ip->ip_p;
1218                 src_ip = ip->ip_src;
1219                 dst_ip = ip->ip_dst;
1220                 offset = ntohs(ip->ip_off) & IP_OFFMASK;
1221                 iplen = ntohs(ip->ip_len);
1222
1223                 if (offset == 0) {
1224                         switch (proto) {
1225                         case IPPROTO_TCP:
1226                                 PULLUP_TO(hlen, ulp, struct tcphdr);
1227                                 dst_port = TCP(ulp)->th_dport;
1228                                 src_port = TCP(ulp)->th_sport;
1229                                 /* save flags for dynamic rules */
1230                                 args->f_id._flags = TCP(ulp)->th_flags;
1231                                 break;
1232
1233                         case IPPROTO_SCTP:
1234                                 PULLUP_TO(hlen, ulp, struct sctphdr);
1235                                 src_port = SCTP(ulp)->src_port;
1236                                 dst_port = SCTP(ulp)->dest_port;
1237                                 break;
1238
1239                         case IPPROTO_UDP:
1240                                 PULLUP_TO(hlen, ulp, struct udphdr);
1241                                 dst_port = UDP(ulp)->uh_dport;
1242                                 src_port = UDP(ulp)->uh_sport;
1243                                 break;
1244
1245                         case IPPROTO_ICMP:
1246                                 PULLUP_TO(hlen, ulp, struct icmphdr);
1247                                 //args->f_id.flags = ICMP(ulp)->icmp_type;
1248                                 break;
1249
1250                         default:
1251                                 break;
1252                         }
1253                 }
1254
1255                 ip = mtod(m, struct ip *);
1256                 args->f_id.src_ip = ntohl(src_ip.s_addr);
1257                 args->f_id.dst_ip = ntohl(dst_ip.s_addr);
1258         }
1259 #undef PULLUP_TO
1260         pktlen = iplen < pktlen ? iplen: pktlen;
1261         if (proto) { /* we may have port numbers, store them */
1262                 args->f_id.proto = proto;
1263                 args->f_id.src_port = src_port = ntohs(src_port);
1264                 args->f_id.dst_port = dst_port = ntohs(dst_port);
1265         }
1266
1267         IPFW_PF_RLOCK(chain);
1268         if (! V_ipfw_vnet_ready) { /* shutting down, leave NOW. */
1269                 IPFW_PF_RUNLOCK(chain);
1270                 return (IP_FW_PASS);    /* accept */
1271         }
1272         if (args->rule.slot) {
1273                 /*
1274                  * Packet has already been tagged as a result of a previous
1275                  * match on rule args->rule aka args->rule_id (PIPE, QUEUE,
1276                  * REASS, NETGRAPH, DIVERT/TEE...)
1277                  * Validate the slot and continue from the next one
1278                  * if still present, otherwise do a lookup.
1279                  */
1280                 f_pos = (args->rule.chain_id == chain->id) ?
1281                     args->rule.slot :
1282                     ipfw_find_rule(chain, args->rule.rulenum,
1283                         args->rule.rule_id);
1284         } else {
1285                 f_pos = 0;
1286         }
1287
1288         /*
1289          * Now scan the rules, and parse microinstructions for each rule.
1290          * We have two nested loops and an inner switch. Sometimes we
1291          * need to break out of one or both loops, or re-enter one of
1292          * the loops with updated variables. Loop variables are:
1293          *
1294          *      f_pos (outer loop) points to the current rule.
1295          *              On output it points to the matching rule.
1296          *      done (outer loop) is used as a flag to break the loop.
1297          *      l (inner loop)  residual length of current rule.
1298          *              cmd points to the current microinstruction.
1299          *
1300          * We break the inner loop by setting l=0 and possibly
1301          * cmdlen=0 if we don't want to advance cmd.
1302          * We break the outer loop by setting done=1
1303          * We can restart the inner loop by setting l>0 and f_pos, f, cmd
1304          * as needed.
1305          */
1306         for (; f_pos < chain->n_rules; f_pos++) {
1307                 ipfw_insn *cmd;
1308                 uint32_t tablearg = 0;
1309                 int l, cmdlen, skip_or; /* skip rest of OR block */
1310                 struct ip_fw *f;
1311
1312                 f = chain->map[f_pos];
1313                 if (V_set_disable & (1 << f->set) )
1314                         continue;
1315
1316                 skip_or = 0;
1317                 for (l = f->cmd_len, cmd = f->cmd ; l > 0 ;
1318                     l -= cmdlen, cmd += cmdlen) {
1319                         int match;
1320
1321                         /*
1322                          * check_body is a jump target used when we find a
1323                          * CHECK_STATE, and need to jump to the body of
1324                          * the target rule.
1325                          */
1326
1327 /* check_body: */
1328                         cmdlen = F_LEN(cmd);
1329                         /*
1330                          * An OR block (insn_1 || .. || insn_n) has the
1331                          * F_OR bit set in all but the last instruction.
1332                          * The first match will set "skip_or", and cause
1333                          * the following instructions to be skipped until
1334                          * past the one with the F_OR bit clear.
1335                          */
1336                         if (skip_or) {          /* skip this instruction */
1337                                 if ((cmd->len & F_OR) == 0)
1338                                         skip_or = 0;    /* next one is good */
1339                                 continue;
1340                         }
1341                         match = 0; /* set to 1 if we succeed */
1342
1343                         switch (cmd->opcode) {
1344                         /*
1345                          * The first set of opcodes compares the packet's
1346                          * fields with some pattern, setting 'match' if a
1347                          * match is found. At the end of the loop there is
1348                          * logic to deal with F_NOT and F_OR flags associated
1349                          * with the opcode.
1350                          */
1351                         case O_NOP:
1352                                 match = 1;
1353                                 break;
1354
1355                         case O_FORWARD_MAC:
1356                                 printf("ipfw: opcode %d unimplemented\n",
1357                                     cmd->opcode);
1358                                 break;
1359
1360                         case O_GID:
1361                         case O_UID:
1362                         case O_JAIL:
1363                                 /*
1364                                  * We only check offset == 0 && proto != 0,
1365                                  * as this ensures that we have a
1366                                  * packet with the ports info.
1367                                  */
1368                                 if (offset != 0)
1369                                         break;
1370                                 if (proto == IPPROTO_TCP ||
1371                                     proto == IPPROTO_UDP)
1372                                         match = check_uidgid(
1373                                                     (ipfw_insn_u32 *)cmd,
1374                                                     args, &ucred_lookup,
1375 #ifdef __FreeBSD__
1376                                                     &ucred_cache);
1377 #else
1378                                                     (void *)&ucred_cache);
1379 #endif
1380                                 break;
1381
1382                         case O_RECV:
1383                                 match = iface_match(m->m_pkthdr.rcvif,
1384                                     (ipfw_insn_if *)cmd, chain, &tablearg);
1385                                 break;
1386
1387                         case O_XMIT:
1388                                 match = iface_match(oif, (ipfw_insn_if *)cmd,
1389                                     chain, &tablearg);
1390                                 break;
1391
1392                         case O_VIA:
1393                                 match = iface_match(oif ? oif :
1394                                     m->m_pkthdr.rcvif, (ipfw_insn_if *)cmd,
1395                                     chain, &tablearg);
1396                                 break;
1397
1398                         case O_MACADDR2:
1399                                 if (args->eh != NULL) { /* have MAC header */
1400                                         u_int32_t *want = (u_int32_t *)
1401                                                 ((ipfw_insn_mac *)cmd)->addr;
1402                                         u_int32_t *mask = (u_int32_t *)
1403                                                 ((ipfw_insn_mac *)cmd)->mask;
1404                                         u_int32_t *hdr = (u_int32_t *)args->eh;
1405
1406                                         match =
1407                                             ( want[0] == (hdr[0] & mask[0]) &&
1408                                               want[1] == (hdr[1] & mask[1]) &&
1409                                               want[2] == (hdr[2] & mask[2]) );
1410                                 }
1411                                 break;
1412
1413                         case O_MAC_TYPE:
1414                                 if (args->eh != NULL) {
1415                                         u_int16_t *p =
1416                                             ((ipfw_insn_u16 *)cmd)->ports;
1417                                         int i;
1418
1419                                         for (i = cmdlen - 1; !match && i>0;
1420                                             i--, p += 2)
1421                                                 match = (etype >= p[0] &&
1422                                                     etype <= p[1]);
1423                                 }
1424                                 break;
1425
1426                         case O_FRAG:
1427                                 match = (offset != 0);
1428                                 break;
1429
1430                         case O_IN:      /* "out" is "not in" */
1431                                 match = (oif == NULL);
1432                                 break;
1433
1434                         case O_LAYER2:
1435                                 match = (args->eh != NULL);
1436                                 break;
1437
1438                         case O_DIVERTED:
1439                             {
1440                                 /* For diverted packets, args->rule.info
1441                                  * contains the divert port (in host format)
1442                                  * reason and direction.
1443                                  */
1444                                 uint32_t i = args->rule.info;
1445                                 match = (i&IPFW_IS_MASK) == IPFW_IS_DIVERT &&
1446                                     cmd->arg1 & ((i & IPFW_INFO_IN) ? 1 : 2);
1447                             }
1448                                 break;
1449
1450                         case O_PROTO:
1451                                 /*
1452                                  * We do not allow an arg of 0 so the
1453                                  * check of "proto" only suffices.
1454                                  */
1455                                 match = (proto == cmd->arg1);
1456                                 break;
1457
1458                         case O_IP_SRC:
1459                                 match = is_ipv4 &&
1460                                     (((ipfw_insn_ip *)cmd)->addr.s_addr ==
1461                                     src_ip.s_addr);
1462                                 break;
1463
1464                         case O_IP_DST_LOOKUP:
1465                         {
1466                                 void *pkey;
1467                                 uint32_t vidx, key;
1468                                 uint16_t keylen;
1469
1470                                 if (cmdlen > F_INSN_SIZE(ipfw_insn_u32)) {
1471                                         /* Determine lookup key type */
1472                                         vidx = ((ipfw_insn_u32 *)cmd)->d[1];
1473                                         if (vidx != 4 /* uid */ &&
1474                                             vidx != 5 /* jail */ &&
1475                                             is_ipv6 == 0 && is_ipv4 == 0)
1476                                                 break;
1477                                         /* Determine key length */
1478                                         if (vidx == 0 /* dst-ip */ ||
1479                                             vidx == 1 /* src-ip */)
1480                                                 keylen = is_ipv6 ?
1481                                                     sizeof(struct in6_addr):
1482                                                     sizeof(in_addr_t);
1483                                         else {
1484                                                 keylen = sizeof(key);
1485                                                 pkey = &key;
1486                                         }
1487                                         if (vidx == 0 /* dst-ip */)
1488                                                 pkey = is_ipv4 ? (void *)&dst_ip:
1489                                                     (void *)&args->f_id.dst_ip6;
1490                                         else if (vidx == 1 /* src-ip */)
1491                                                 pkey = is_ipv4 ? (void *)&src_ip:
1492                                                     (void *)&args->f_id.src_ip6;
1493                                         else if (vidx == 6 /* dscp */) {
1494                                                 if (is_ipv4)
1495                                                         key = ip->ip_tos >> 2;
1496                                                 else {
1497                                                         key = args->f_id.flow_id6;
1498                                                         key = (key & 0x0f) << 2 |
1499                                                             (key & 0xf000) >> 14;
1500                                                 }
1501                                                 key &= 0x3f;
1502                                         } else if (vidx == 2 /* dst-port */ ||
1503                                             vidx == 3 /* src-port */) {
1504                                                 /* Skip fragments */
1505                                                 if (offset != 0)
1506                                                         break;
1507                                                 /* Skip proto without ports */
1508                                                 if (proto != IPPROTO_TCP &&
1509                                                     proto != IPPROTO_UDP &&
1510                                                     proto != IPPROTO_SCTP)
1511                                                         break;
1512                                                 if (vidx == 2 /* dst-port */)
1513                                                         key = dst_port;
1514                                                 else
1515                                                         key = src_port;
1516                                         }
1517 #ifndef USERSPACE
1518                                         else if (vidx == 4 /* uid */ ||
1519                                             vidx == 5 /* jail */) {
1520                                                 check_uidgid(
1521                                                     (ipfw_insn_u32 *)cmd,
1522                                                     args, &ucred_lookup,
1523 #ifdef __FreeBSD__
1524                                                     &ucred_cache);
1525                                                 if (vidx == 4 /* uid */)
1526                                                         key = ucred_cache->cr_uid;
1527                                                 else if (vidx == 5 /* jail */)
1528                                                         key = ucred_cache->cr_prison->pr_id;
1529 #else /* !__FreeBSD__ */
1530                                                     (void *)&ucred_cache);
1531                                                 if (vidx == 4 /* uid */)
1532                                                         key = ucred_cache.uid;
1533                                                 else if (vidx == 5 /* jail */)
1534                                                         key = ucred_cache.xid;
1535 #endif /* !__FreeBSD__ */
1536                                         }
1537 #endif /* !USERSPACE */
1538                                         else
1539                                                 break;
1540                                         match = ipfw_lookup_table(chain,
1541                                             cmd->arg1, keylen, pkey, &vidx);
1542                                         if (!match)
1543                                                 break;
1544                                         tablearg = vidx;
1545                                         break;
1546                                 }
1547                                 /* cmdlen =< F_INSN_SIZE(ipfw_insn_u32) */
1548                                 /* FALLTHROUGH */
1549                         }
1550                         case O_IP_SRC_LOOKUP:
1551                         {
1552                                 void *pkey;
1553                                 uint32_t vidx;
1554                                 uint16_t keylen;
1555
1556                                 if (is_ipv4) {
1557                                         keylen = sizeof(in_addr_t);
1558                                         if (cmd->opcode == O_IP_DST_LOOKUP)
1559                                                 pkey = &dst_ip;
1560                                         else
1561                                                 pkey = &src_ip;
1562                                 } else if (is_ipv6) {
1563                                         keylen = sizeof(struct in6_addr);
1564                                         if (cmd->opcode == O_IP_DST_LOOKUP)
1565                                                 pkey = &args->f_id.dst_ip6;
1566                                         else
1567                                                 pkey = &args->f_id.src_ip6;
1568                                 } else
1569                                         break;
1570                                 match = ipfw_lookup_table(chain, cmd->arg1,
1571                                     keylen, pkey, &vidx);
1572                                 if (!match)
1573                                         break;
1574                                 if (cmdlen == F_INSN_SIZE(ipfw_insn_u32)) {
1575                                         match = ((ipfw_insn_u32 *)cmd)->d[0] ==
1576                                             TARG_VAL(chain, vidx, tag);
1577                                         if (!match)
1578                                                 break;
1579                                 }
1580                                 tablearg = vidx;
1581                                 break;
1582                         }
1583
1584                         case O_IP_FLOW_LOOKUP:
1585                                 {
1586                                         uint32_t v = 0;
1587                                         match = ipfw_lookup_table(chain,
1588                                             cmd->arg1, 0, &args->f_id, &v);
1589                                         if (cmdlen == F_INSN_SIZE(ipfw_insn_u32))
1590                                                 match = ((ipfw_insn_u32 *)cmd)->d[0] ==
1591                                                     TARG_VAL(chain, v, tag);
1592                                         if (match)
1593                                                 tablearg = v;
1594                                 }
1595                                 break;
1596                         case O_IP_SRC_MASK:
1597                         case O_IP_DST_MASK:
1598                                 if (is_ipv4) {
1599                                     uint32_t a =
1600                                         (cmd->opcode == O_IP_DST_MASK) ?
1601                                             dst_ip.s_addr : src_ip.s_addr;
1602                                     uint32_t *p = ((ipfw_insn_u32 *)cmd)->d;
1603                                     int i = cmdlen-1;
1604
1605                                     for (; !match && i>0; i-= 2, p+= 2)
1606                                         match = (p[0] == (a & p[1]));
1607                                 }
1608                                 break;
1609
1610                         case O_IP_SRC_ME:
1611                                 if (is_ipv4) {
1612                                         match = in_localip(src_ip);
1613                                         break;
1614                                 }
1615 #ifdef INET6
1616                                 /* FALLTHROUGH */
1617                         case O_IP6_SRC_ME:
1618                                 match= is_ipv6 && ipfw_localip6(&args->f_id.src_ip6);
1619 #endif
1620                                 break;
1621
1622                         case O_IP_DST_SET:
1623                         case O_IP_SRC_SET:
1624                                 if (is_ipv4) {
1625                                         u_int32_t *d = (u_int32_t *)(cmd+1);
1626                                         u_int32_t addr =
1627                                             cmd->opcode == O_IP_DST_SET ?
1628                                                 args->f_id.dst_ip :
1629                                                 args->f_id.src_ip;
1630
1631                                             if (addr < d[0])
1632                                                     break;
1633                                             addr -= d[0]; /* subtract base */
1634                                             match = (addr < cmd->arg1) &&
1635                                                 ( d[ 1 + (addr>>5)] &
1636                                                   (1<<(addr & 0x1f)) );
1637                                 }
1638                                 break;
1639
1640                         case O_IP_DST:
1641                                 match = is_ipv4 &&
1642                                     (((ipfw_insn_ip *)cmd)->addr.s_addr ==
1643                                     dst_ip.s_addr);
1644                                 break;
1645
1646                         case O_IP_DST_ME:
1647                                 if (is_ipv4) {
1648                                         match = in_localip(dst_ip);
1649                                         break;
1650                                 }
1651 #ifdef INET6
1652                                 /* FALLTHROUGH */
1653                         case O_IP6_DST_ME:
1654                                 match= is_ipv6 && ipfw_localip6(&args->f_id.dst_ip6);
1655 #endif
1656                                 break;
1657
1658
1659                         case O_IP_SRCPORT:
1660                         case O_IP_DSTPORT:
1661                                 /*
1662                                  * offset == 0 && proto != 0 is enough
1663                                  * to guarantee that we have a
1664                                  * packet with port info.
1665                                  */
1666                                 if ((proto==IPPROTO_UDP || proto==IPPROTO_TCP ||
1667                                     proto==IPPROTO_SCTP) && offset == 0) {
1668                                         u_int16_t x =
1669                                             (cmd->opcode == O_IP_SRCPORT) ?
1670                                                 src_port : dst_port ;
1671                                         u_int16_t *p =
1672                                             ((ipfw_insn_u16 *)cmd)->ports;
1673                                         int i;
1674
1675                                         for (i = cmdlen - 1; !match && i>0;
1676                                             i--, p += 2)
1677                                                 match = (x>=p[0] && x<=p[1]);
1678                                 }
1679                                 break;
1680
1681                         case O_ICMPTYPE:
1682                                 match = (offset == 0 && proto==IPPROTO_ICMP &&
1683                                     icmptype_match(ICMP(ulp), (ipfw_insn_u32 *)cmd) );
1684                                 break;
1685
1686 #ifdef INET6
1687                         case O_ICMP6TYPE:
1688                                 match = is_ipv6 && offset == 0 &&
1689                                     proto==IPPROTO_ICMPV6 &&
1690                                     icmp6type_match(
1691                                         ICMP6(ulp)->icmp6_type,
1692                                         (ipfw_insn_u32 *)cmd);
1693                                 break;
1694 #endif /* INET6 */
1695
1696                         case O_IPOPT:
1697                                 match = (is_ipv4 &&
1698                                     ipopts_match(ip, cmd) );
1699                                 break;
1700
1701                         case O_IPVER:
1702                                 match = (is_ipv4 &&
1703                                     cmd->arg1 == ip->ip_v);
1704                                 break;
1705
1706                         case O_IPID:
1707                         case O_IPLEN:
1708                         case O_IPTTL:
1709                                 if (is_ipv4) {  /* only for IP packets */
1710                                     uint16_t x;
1711                                     uint16_t *p;
1712                                     int i;
1713
1714                                     if (cmd->opcode == O_IPLEN)
1715                                         x = iplen;
1716                                     else if (cmd->opcode == O_IPTTL)
1717                                         x = ip->ip_ttl;
1718                                     else /* must be IPID */
1719                                         x = ntohs(ip->ip_id);
1720                                     if (cmdlen == 1) {
1721                                         match = (cmd->arg1 == x);
1722                                         break;
1723                                     }
1724                                     /* otherwise we have ranges */
1725                                     p = ((ipfw_insn_u16 *)cmd)->ports;
1726                                     i = cmdlen - 1;
1727                                     for (; !match && i>0; i--, p += 2)
1728                                         match = (x >= p[0] && x <= p[1]);
1729                                 }
1730                                 break;
1731
1732                         case O_IPPRECEDENCE:
1733                                 match = (is_ipv4 &&
1734                                     (cmd->arg1 == (ip->ip_tos & 0xe0)) );
1735                                 break;
1736
1737                         case O_IPTOS:
1738                                 match = (is_ipv4 &&
1739                                     flags_match(cmd, ip->ip_tos));
1740                                 break;
1741
1742                         case O_DSCP:
1743                             {
1744                                 uint32_t *p;
1745                                 uint16_t x;
1746
1747                                 p = ((ipfw_insn_u32 *)cmd)->d;
1748
1749                                 if (is_ipv4)
1750                                         x = ip->ip_tos >> 2;
1751                                 else if (is_ipv6) {
1752                                         uint8_t *v;
1753                                         v = &((struct ip6_hdr *)ip)->ip6_vfc;
1754                                         x = (*v & 0x0F) << 2;
1755                                         v++;
1756                                         x |= *v >> 6;
1757                                 } else
1758                                         break;
1759
1760                                 /* DSCP bitmask is stored as low_u32 high_u32 */
1761                                 if (x >= 32)
1762                                         match = *(p + 1) & (1 << (x - 32));
1763                                 else
1764                                         match = *p & (1 << x);
1765                             }
1766                                 break;
1767
1768                         case O_TCPDATALEN:
1769                                 if (proto == IPPROTO_TCP && offset == 0) {
1770                                     struct tcphdr *tcp;
1771                                     uint16_t x;
1772                                     uint16_t *p;
1773                                     int i;
1774 #ifdef INET6
1775                                     if (is_ipv6) {
1776                                             struct ip6_hdr *ip6;
1777
1778                                             ip6 = (struct ip6_hdr *)ip;
1779                                             if (ip6->ip6_plen == 0) {
1780                                                     /*
1781                                                      * Jumbo payload is not
1782                                                      * supported by this
1783                                                      * opcode.
1784                                                      */
1785                                                     break;
1786                                             }
1787                                             x = iplen - hlen;
1788                                     } else
1789 #endif /* INET6 */
1790                                             x = iplen - (ip->ip_hl << 2);
1791                                     tcp = TCP(ulp);
1792                                     x -= tcp->th_off << 2;
1793                                     if (cmdlen == 1) {
1794                                         match = (cmd->arg1 == x);
1795                                         break;
1796                                     }
1797                                     /* otherwise we have ranges */
1798                                     p = ((ipfw_insn_u16 *)cmd)->ports;
1799                                     i = cmdlen - 1;
1800                                     for (; !match && i>0; i--, p += 2)
1801                                         match = (x >= p[0] && x <= p[1]);
1802                                 }
1803                                 break;
1804
1805                         case O_TCPFLAGS:
1806                                 match = (proto == IPPROTO_TCP && offset == 0 &&
1807                                     flags_match(cmd, TCP(ulp)->th_flags));
1808                                 break;
1809
1810                         case O_TCPOPTS:
1811                                 if (proto == IPPROTO_TCP && offset == 0 && ulp){
1812                                         PULLUP_LEN(hlen, ulp,
1813                                             (TCP(ulp)->th_off << 2));
1814                                         match = tcpopts_match(TCP(ulp), cmd);
1815                                 }
1816                                 break;
1817
1818                         case O_TCPSEQ:
1819                                 match = (proto == IPPROTO_TCP && offset == 0 &&
1820                                     ((ipfw_insn_u32 *)cmd)->d[0] ==
1821                                         TCP(ulp)->th_seq);
1822                                 break;
1823
1824                         case O_TCPACK:
1825                                 match = (proto == IPPROTO_TCP && offset == 0 &&
1826                                     ((ipfw_insn_u32 *)cmd)->d[0] ==
1827                                         TCP(ulp)->th_ack);
1828                                 break;
1829
1830                         case O_TCPWIN:
1831                                 if (proto == IPPROTO_TCP && offset == 0) {
1832                                     uint16_t x;
1833                                     uint16_t *p;
1834                                     int i;
1835
1836                                     x = ntohs(TCP(ulp)->th_win);
1837                                     if (cmdlen == 1) {
1838                                         match = (cmd->arg1 == x);
1839                                         break;
1840                                     }
1841                                     /* Otherwise we have ranges. */
1842                                     p = ((ipfw_insn_u16 *)cmd)->ports;
1843                                     i = cmdlen - 1;
1844                                     for (; !match && i > 0; i--, p += 2)
1845                                         match = (x >= p[0] && x <= p[1]);
1846                                 }
1847                                 break;
1848
1849                         case O_ESTAB:
1850                                 /* reject packets which have SYN only */
1851                                 /* XXX should i also check for TH_ACK ? */
1852                                 match = (proto == IPPROTO_TCP && offset == 0 &&
1853                                     (TCP(ulp)->th_flags &
1854                                      (TH_RST | TH_ACK | TH_SYN)) != TH_SYN);
1855                                 break;
1856
1857                         case O_ALTQ: {
1858                                 struct pf_mtag *at;
1859                                 struct m_tag *mtag;
1860                                 ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
1861
1862                                 /*
1863                                  * ALTQ uses mbuf tags from another
1864                                  * packet filtering system - pf(4).
1865                                  * We allocate a tag in its format
1866                                  * and fill it in, pretending to be pf(4).
1867                                  */
1868                                 match = 1;
1869                                 at = pf_find_mtag(m);
1870                                 if (at != NULL && at->qid != 0)
1871                                         break;
1872                                 mtag = m_tag_get(PACKET_TAG_PF,
1873                                     sizeof(struct pf_mtag), M_NOWAIT | M_ZERO);
1874                                 if (mtag == NULL) {
1875                                         /*
1876                                          * Let the packet fall back to the
1877                                          * default ALTQ.
1878                                          */
1879                                         break;
1880                                 }
1881                                 m_tag_prepend(m, mtag);
1882                                 at = (struct pf_mtag *)(mtag + 1);
1883                                 at->qid = altq->qid;
1884                                 at->hdr = ip;
1885                                 break;
1886                         }
1887
1888                         case O_LOG:
1889                                 ipfw_log(chain, f, hlen, args, m,
1890                                     oif, offset | ip6f_mf, tablearg, ip);
1891                                 match = 1;
1892                                 break;
1893
1894                         case O_PROB:
1895                                 match = (random()<((ipfw_insn_u32 *)cmd)->d[0]);
1896                                 break;
1897
1898                         case O_VERREVPATH:
1899                                 /* Outgoing packets automatically pass/match */
1900                                 match = ((oif != NULL) ||
1901                                     (m->m_pkthdr.rcvif == NULL) ||
1902                                     (
1903 #ifdef INET6
1904                                     is_ipv6 ?
1905                                         verify_path6(&(args->f_id.src_ip6),
1906                                             m->m_pkthdr.rcvif, args->f_id.fib) :
1907 #endif
1908                                     verify_path(src_ip, m->m_pkthdr.rcvif,
1909                                         args->f_id.fib)));
1910                                 break;
1911
1912                         case O_VERSRCREACH:
1913                                 /* Outgoing packets automatically pass/match */
1914                                 match = (hlen > 0 && ((oif != NULL) ||
1915 #ifdef INET6
1916                                     is_ipv6 ?
1917                                         verify_path6(&(args->f_id.src_ip6),
1918                                             NULL, args->f_id.fib) :
1919 #endif
1920                                     verify_path(src_ip, NULL, args->f_id.fib)));
1921                                 break;
1922
1923                         case O_ANTISPOOF:
1924                                 /* Outgoing packets automatically pass/match */
1925                                 if (oif == NULL && hlen > 0 &&
1926                                     (  (is_ipv4 && in_localaddr(src_ip))
1927 #ifdef INET6
1928                                     || (is_ipv6 &&
1929                                         in6_localaddr(&(args->f_id.src_ip6)))
1930 #endif
1931                                     ))
1932                                         match =
1933 #ifdef INET6
1934                                             is_ipv6 ? verify_path6(
1935                                                 &(args->f_id.src_ip6),
1936                                                 m->m_pkthdr.rcvif,
1937                                                 args->f_id.fib) :
1938 #endif
1939                                             verify_path(src_ip,
1940                                                 m->m_pkthdr.rcvif,
1941                                                 args->f_id.fib);
1942                                 else
1943                                         match = 1;
1944                                 break;
1945
1946                         case O_IPSEC:
1947                                 match = (m_tag_find(m,
1948                                     PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL);
1949                                 /* otherwise no match */
1950                                 break;
1951
1952 #ifdef INET6
1953                         case O_IP6_SRC:
1954                                 match = is_ipv6 &&
1955                                     IN6_ARE_ADDR_EQUAL(&args->f_id.src_ip6,
1956                                     &((ipfw_insn_ip6 *)cmd)->addr6);
1957                                 break;
1958
1959                         case O_IP6_DST:
1960                                 match = is_ipv6 &&
1961                                 IN6_ARE_ADDR_EQUAL(&args->f_id.dst_ip6,
1962                                     &((ipfw_insn_ip6 *)cmd)->addr6);
1963                                 break;
1964                         case O_IP6_SRC_MASK:
1965                         case O_IP6_DST_MASK:
1966                                 if (is_ipv6) {
1967                                         int i = cmdlen - 1;
1968                                         struct in6_addr p;
1969                                         struct in6_addr *d =
1970                                             &((ipfw_insn_ip6 *)cmd)->addr6;
1971
1972                                         for (; !match && i > 0; d += 2,
1973                                             i -= F_INSN_SIZE(struct in6_addr)
1974                                             * 2) {
1975                                                 p = (cmd->opcode ==
1976                                                     O_IP6_SRC_MASK) ?
1977                                                     args->f_id.src_ip6:
1978                                                     args->f_id.dst_ip6;
1979                                                 APPLY_MASK(&p, &d[1]);
1980                                                 match =
1981                                                     IN6_ARE_ADDR_EQUAL(&d[0],
1982                                                     &p);
1983                                         }
1984                                 }
1985                                 break;
1986
1987                         case O_FLOW6ID:
1988                                 match = is_ipv6 &&
1989                                     flow6id_match(args->f_id.flow_id6,
1990                                     (ipfw_insn_u32 *) cmd);
1991                                 break;
1992
1993                         case O_EXT_HDR:
1994                                 match = is_ipv6 &&
1995                                     (ext_hd & ((ipfw_insn *) cmd)->arg1);
1996                                 break;
1997
1998                         case O_IP6:
1999                                 match = is_ipv6;
2000                                 break;
2001 #endif
2002
2003                         case O_IP4:
2004                                 match = is_ipv4;
2005                                 break;
2006
2007                         case O_TAG: {
2008                                 struct m_tag *mtag;
2009                                 uint32_t tag = TARG(cmd->arg1, tag);
2010
2011                                 /* Packet is already tagged with this tag? */
2012                                 mtag = m_tag_locate(m, MTAG_IPFW, tag, NULL);
2013
2014                                 /* We have `untag' action when F_NOT flag is
2015                                  * present. And we must remove this mtag from
2016                                  * mbuf and reset `match' to zero (`match' will
2017                                  * be inversed later).
2018                                  * Otherwise we should allocate new mtag and
2019                                  * push it into mbuf.
2020                                  */
2021                                 if (cmd->len & F_NOT) { /* `untag' action */
2022                                         if (mtag != NULL)
2023                                                 m_tag_delete(m, mtag);
2024                                         match = 0;
2025                                 } else {
2026                                         if (mtag == NULL) {
2027                                                 mtag = m_tag_alloc( MTAG_IPFW,
2028                                                     tag, 0, M_NOWAIT);
2029                                                 if (mtag != NULL)
2030                                                         m_tag_prepend(m, mtag);
2031                                         }
2032                                         match = 1;
2033                                 }
2034                                 break;
2035                         }
2036
2037                         case O_FIB: /* try match the specified fib */
2038                                 if (args->f_id.fib == cmd->arg1)
2039                                         match = 1;
2040                                 break;
2041
2042                         case O_SOCKARG: {
2043 #ifndef USERSPACE       /* not supported in userspace */
2044                                 struct inpcb *inp = args->inp;
2045                                 struct inpcbinfo *pi;
2046
2047                                 if (is_ipv6) /* XXX can we remove this ? */
2048                                         break;
2049
2050                                 if (proto == IPPROTO_TCP)
2051                                         pi = &V_tcbinfo;
2052                                 else if (proto == IPPROTO_UDP)
2053                                         pi = &V_udbinfo;
2054                                 else
2055                                         break;
2056
2057                                 /*
2058                                  * XXXRW: so_user_cookie should almost
2059                                  * certainly be inp_user_cookie?
2060                                  */
2061
2062                                 /* For incoming packet, lookup up the
2063                                 inpcb using the src/dest ip/port tuple */
2064                                 if (inp == NULL) {
2065                                         inp = in_pcblookup(pi,
2066                                                 src_ip, htons(src_port),
2067                                                 dst_ip, htons(dst_port),
2068                                                 INPLOOKUP_RLOCKPCB, NULL);
2069                                         if (inp != NULL) {
2070                                                 tablearg =
2071                                                     inp->inp_socket->so_user_cookie;
2072                                                 if (tablearg)
2073                                                         match = 1;
2074                                                 INP_RUNLOCK(inp);
2075                                         }
2076                                 } else {
2077                                         if (inp->inp_socket) {
2078                                                 tablearg =
2079                                                     inp->inp_socket->so_user_cookie;
2080                                                 if (tablearg)
2081                                                         match = 1;
2082                                         }
2083                                 }
2084 #endif /* !USERSPACE */
2085                                 break;
2086                         }
2087
2088                         case O_TAGGED: {
2089                                 struct m_tag *mtag;
2090                                 uint32_t tag = TARG(cmd->arg1, tag);
2091
2092                                 if (cmdlen == 1) {
2093                                         match = m_tag_locate(m, MTAG_IPFW,
2094                                             tag, NULL) != NULL;
2095                                         break;
2096                                 }
2097
2098                                 /* we have ranges */
2099                                 for (mtag = m_tag_first(m);
2100                                     mtag != NULL && !match;
2101                                     mtag = m_tag_next(m, mtag)) {
2102                                         uint16_t *p;
2103                                         int i;
2104
2105                                         if (mtag->m_tag_cookie != MTAG_IPFW)
2106                                                 continue;
2107
2108                                         p = ((ipfw_insn_u16 *)cmd)->ports;
2109                                         i = cmdlen - 1;
2110                                         for(; !match && i > 0; i--, p += 2)
2111                                                 match =
2112                                                     mtag->m_tag_id >= p[0] &&
2113                                                     mtag->m_tag_id <= p[1];
2114                                 }
2115                                 break;
2116                         }
2117
2118                         /*
2119                          * The second set of opcodes represents 'actions',
2120                          * i.e. the terminal part of a rule once the packet
2121                          * matches all previous patterns.
2122                          * Typically there is only one action for each rule,
2123                          * and the opcode is stored at the end of the rule
2124                          * (but there are exceptions -- see below).
2125                          *
2126                          * In general, here we set retval and terminate the
2127                          * outer loop (would be a 'break 3' in some language,
2128                          * but we need to set l=0, done=1)
2129                          *
2130                          * Exceptions:
2131                          * O_COUNT and O_SKIPTO actions:
2132                          *   instead of terminating, we jump to the next rule
2133                          *   (setting l=0), or to the SKIPTO target (setting
2134                          *   f/f_len, cmd and l as needed), respectively.
2135                          *
2136                          * O_TAG, O_LOG and O_ALTQ action parameters:
2137                          *   perform some action and set match = 1;
2138                          *
2139                          * O_LIMIT and O_KEEP_STATE: these opcodes are
2140                          *   not real 'actions', and are stored right
2141                          *   before the 'action' part of the rule.
2142                          *   These opcodes try to install an entry in the
2143                          *   state tables; if successful, we continue with
2144                          *   the next opcode (match=1; break;), otherwise
2145                          *   the packet must be dropped (set retval,
2146                          *   break loops with l=0, done=1)
2147                          *
2148                          * O_PROBE_STATE and O_CHECK_STATE: these opcodes
2149                          *   cause a lookup of the state table, and a jump
2150                          *   to the 'action' part of the parent rule
2151                          *   if an entry is found, or
2152                          *   (CHECK_STATE only) a jump to the next rule if
2153                          *   the entry is not found.
2154                          *   The result of the lookup is cached so that
2155                          *   further instances of these opcodes become NOPs.
2156                          *   The jump to the next rule is done by setting
2157                          *   l=0, cmdlen=0.
2158                          */
2159                         case O_LIMIT:
2160                         case O_KEEP_STATE:
2161                                 if (ipfw_install_state(chain, f,
2162                                     (ipfw_insn_limit *)cmd, args, tablearg)) {
2163                                         /* error or limit violation */
2164                                         retval = IP_FW_DENY;
2165                                         l = 0;  /* exit inner loop */
2166                                         done = 1; /* exit outer loop */
2167                                 }
2168                                 match = 1;
2169                                 break;
2170
2171                         case O_PROBE_STATE:
2172                         case O_CHECK_STATE:
2173                                 /*
2174                                  * dynamic rules are checked at the first
2175                                  * keep-state or check-state occurrence,
2176                                  * with the result being stored in dyn_dir
2177                                  * and dyn_name.
2178                                  * The compiler introduces a PROBE_STATE
2179                                  * instruction for us when we have a
2180                                  * KEEP_STATE (because PROBE_STATE needs
2181                                  * to be run first).
2182                                  *
2183                                  * (dyn_dir == MATCH_UNKNOWN) means this is
2184                                  * first lookup for such f_id. Do lookup.
2185                                  *
2186                                  * (dyn_dir != MATCH_UNKNOWN &&
2187                                  *  dyn_name != 0 && dyn_name != cmd->arg1)
2188                                  * means previous lookup didn't find dynamic
2189                                  * rule for specific state name and current
2190                                  * lookup will search rule with another state
2191                                  * name. Redo lookup.
2192                                  *
2193                                  * (dyn_dir != MATCH_UNKNOWN && dyn_name == 0)
2194                                  * means previous lookup was for `any' name
2195                                  * and it didn't find rule. No need to do
2196                                  * lookup again.
2197                                  */
2198                                 if ((dyn_dir == MATCH_UNKNOWN ||
2199                                     (dyn_name != 0 &&
2200                                     dyn_name != cmd->arg1)) &&
2201                                     (q = ipfw_lookup_dyn_rule(&args->f_id,
2202                                      &dyn_dir, proto == IPPROTO_TCP ?
2203                                      TCP(ulp): NULL,
2204                                      (dyn_name = cmd->arg1))) != NULL) {
2205                                         /*
2206                                          * Found dynamic entry, update stats
2207                                          * and jump to the 'action' part of
2208                                          * the parent rule by setting
2209                                          * f, cmd, l and clearing cmdlen.
2210                                          */
2211                                         IPFW_INC_DYN_COUNTER(q, pktlen);
2212                                         /* XXX we would like to have f_pos
2213                                          * readily accessible in the dynamic
2214                                          * rule, instead of having to
2215                                          * lookup q->rule.
2216                                          */
2217                                         f = q->rule;
2218                                         f_pos = ipfw_find_rule(chain,
2219                                                 f->rulenum, f->id);
2220                                         cmd = ACTION_PTR(f);
2221                                         l = f->cmd_len - f->act_ofs;
2222                                         ipfw_dyn_unlock(q);
2223                                         cmdlen = 0;
2224                                         match = 1;
2225                                         break;
2226                                 }
2227                                 /*
2228                                  * Dynamic entry not found. If CHECK_STATE,
2229                                  * skip to next rule, if PROBE_STATE just
2230                                  * ignore and continue with next opcode.
2231                                  */
2232                                 if (cmd->opcode == O_CHECK_STATE)
2233                                         l = 0;  /* exit inner loop */
2234                                 match = 1;
2235                                 break;
2236
2237                         case O_ACCEPT:
2238                                 retval = 0;     /* accept */
2239                                 l = 0;          /* exit inner loop */
2240                                 done = 1;       /* exit outer loop */
2241                                 break;
2242
2243                         case O_PIPE:
2244                         case O_QUEUE:
2245                                 set_match(args, f_pos, chain);
2246                                 args->rule.info = TARG(cmd->arg1, pipe);
2247                                 if (cmd->opcode == O_PIPE)
2248                                         args->rule.info |= IPFW_IS_PIPE;
2249                                 if (V_fw_one_pass)
2250                                         args->rule.info |= IPFW_ONEPASS;
2251                                 retval = IP_FW_DUMMYNET;
2252                                 l = 0;          /* exit inner loop */
2253                                 done = 1;       /* exit outer loop */
2254                                 break;
2255
2256                         case O_DIVERT:
2257                         case O_TEE:
2258                                 if (args->eh) /* not on layer 2 */
2259                                     break;
2260                                 /* otherwise this is terminal */
2261                                 l = 0;          /* exit inner loop */
2262                                 done = 1;       /* exit outer loop */
2263                                 retval = (cmd->opcode == O_DIVERT) ?
2264                                         IP_FW_DIVERT : IP_FW_TEE;
2265                                 set_match(args, f_pos, chain);
2266                                 args->rule.info = TARG(cmd->arg1, divert);
2267                                 break;
2268
2269                         case O_COUNT:
2270                                 IPFW_INC_RULE_COUNTER(f, pktlen);
2271                                 l = 0;          /* exit inner loop */
2272                                 break;
2273
2274                         case O_SKIPTO:
2275                             IPFW_INC_RULE_COUNTER(f, pktlen);
2276                             f_pos = JUMP(chain, f, cmd->arg1, tablearg, 0);
2277                             /*
2278                              * Skip disabled rules, and re-enter
2279                              * the inner loop with the correct
2280                              * f_pos, f, l and cmd.
2281                              * Also clear cmdlen and skip_or
2282                              */
2283                             for (; f_pos < chain->n_rules - 1 &&
2284                                     (V_set_disable &
2285                                      (1 << chain->map[f_pos]->set));
2286                                     f_pos++)
2287                                 ;
2288                             /* Re-enter the inner loop at the skipto rule. */
2289                             f = chain->map[f_pos];
2290                             l = f->cmd_len;
2291                             cmd = f->cmd;
2292                             match = 1;
2293                             cmdlen = 0;
2294                             skip_or = 0;
2295                             continue;
2296                             break;      /* not reached */
2297
2298                         case O_CALLRETURN: {
2299                                 /*
2300                                  * Implementation of `subroutine' call/return,
2301                                  * in the stack carried in an mbuf tag. This
2302                                  * is different from `skipto' in that any call
2303                                  * address is possible (`skipto' must prevent
2304                                  * backward jumps to avoid endless loops).
2305                                  * We have `return' action when F_NOT flag is
2306                                  * present. The `m_tag_id' field is used as
2307                                  * stack pointer.
2308                                  */
2309                                 struct m_tag *mtag;
2310                                 uint16_t jmpto, *stack;
2311
2312 #define IS_CALL         ((cmd->len & F_NOT) == 0)
2313 #define IS_RETURN       ((cmd->len & F_NOT) != 0)
2314                                 /*
2315                                  * Hand-rolled version of m_tag_locate() with
2316                                  * wildcard `type'.
2317                                  * If not already tagged, allocate new tag.
2318                                  */
2319                                 mtag = m_tag_first(m);
2320                                 while (mtag != NULL) {
2321                                         if (mtag->m_tag_cookie ==
2322                                             MTAG_IPFW_CALL)
2323                                                 break;
2324                                         mtag = m_tag_next(m, mtag);
2325                                 }
2326                                 if (mtag == NULL && IS_CALL) {
2327                                         mtag = m_tag_alloc(MTAG_IPFW_CALL, 0,
2328                                             IPFW_CALLSTACK_SIZE *
2329                                             sizeof(uint16_t), M_NOWAIT);
2330                                         if (mtag != NULL)
2331                                                 m_tag_prepend(m, mtag);
2332                                 }
2333
2334                                 /*
2335                                  * On error both `call' and `return' just
2336                                  * continue with next rule.
2337                                  */
2338                                 if (IS_RETURN && (mtag == NULL ||
2339                                     mtag->m_tag_id == 0)) {
2340                                         l = 0;          /* exit inner loop */
2341                                         break;
2342                                 }
2343                                 if (IS_CALL && (mtag == NULL ||
2344                                     mtag->m_tag_id >= IPFW_CALLSTACK_SIZE)) {
2345                                         printf("ipfw: call stack error, "
2346                                             "go to next rule\n");
2347                                         l = 0;          /* exit inner loop */
2348                                         break;
2349                                 }
2350
2351                                 IPFW_INC_RULE_COUNTER(f, pktlen);
2352                                 stack = (uint16_t *)(mtag + 1);
2353
2354                                 /*
2355                                  * The `call' action may use cached f_pos
2356                                  * (in f->next_rule), whose version is written
2357                                  * in f->next_rule.
2358                                  * The `return' action, however, doesn't have
2359                                  * fixed jump address in cmd->arg1 and can't use
2360                                  * cache.
2361                                  */
2362                                 if (IS_CALL) {
2363                                         stack[mtag->m_tag_id] = f->rulenum;
2364                                         mtag->m_tag_id++;
2365                                         f_pos = JUMP(chain, f, cmd->arg1,
2366                                             tablearg, 1);
2367                                 } else {        /* `return' action */
2368                                         mtag->m_tag_id--;
2369                                         jmpto = stack[mtag->m_tag_id] + 1;
2370                                         f_pos = ipfw_find_rule(chain, jmpto, 0);
2371                                 }
2372
2373                                 /*
2374                                  * Skip disabled rules, and re-enter
2375                                  * the inner loop with the correct
2376                                  * f_pos, f, l and cmd.
2377                                  * Also clear cmdlen and skip_or
2378                                  */
2379                                 for (; f_pos < chain->n_rules - 1 &&
2380                                     (V_set_disable &
2381                                     (1 << chain->map[f_pos]->set)); f_pos++)
2382                                         ;
2383                                 /* Re-enter the inner loop at the dest rule. */
2384                                 f = chain->map[f_pos];
2385                                 l = f->cmd_len;
2386                                 cmd = f->cmd;
2387                                 cmdlen = 0;
2388                                 skip_or = 0;
2389                                 continue;
2390                                 break;  /* NOTREACHED */
2391                         }
2392 #undef IS_CALL
2393 #undef IS_RETURN
2394
2395                         case O_REJECT:
2396                                 /*
2397                                  * Drop the packet and send a reject notice
2398                                  * if the packet is not ICMP (or is an ICMP
2399                                  * query), and it is not multicast/broadcast.
2400                                  */
2401                                 if (hlen > 0 && is_ipv4 && offset == 0 &&
2402                                     (proto != IPPROTO_ICMP ||
2403                                      is_icmp_query(ICMP(ulp))) &&
2404                                     !(m->m_flags & (M_BCAST|M_MCAST)) &&
2405                                     !IN_MULTICAST(ntohl(dst_ip.s_addr))) {
2406                                         send_reject(args, cmd->arg1, iplen, ip);
2407                                         m = args->m;
2408                                 }
2409                                 /* FALLTHROUGH */
2410 #ifdef INET6
2411                         case O_UNREACH6:
2412                                 if (hlen > 0 && is_ipv6 &&
2413                                     ((offset & IP6F_OFF_MASK) == 0) &&
2414                                     (proto != IPPROTO_ICMPV6 ||
2415                                      (is_icmp6_query(icmp6_type) == 1)) &&
2416                                     !(m->m_flags & (M_BCAST|M_MCAST)) &&
2417                                     !IN6_IS_ADDR_MULTICAST(&args->f_id.dst_ip6)) {
2418                                         send_reject6(
2419                                             args, cmd->arg1, hlen,
2420                                             (struct ip6_hdr *)ip);
2421                                         m = args->m;
2422                                 }
2423                                 /* FALLTHROUGH */
2424 #endif
2425                         case O_DENY:
2426                                 retval = IP_FW_DENY;
2427                                 l = 0;          /* exit inner loop */
2428                                 done = 1;       /* exit outer loop */
2429                                 break;
2430
2431                         case O_FORWARD_IP:
2432                                 if (args->eh)   /* not valid on layer2 pkts */
2433                                         break;
2434                                 if (q == NULL || q->rule != f ||
2435                                     dyn_dir == MATCH_FORWARD) {
2436                                     struct sockaddr_in *sa;
2437
2438                                     sa = &(((ipfw_insn_sa *)cmd)->sa);
2439                                     if (sa->sin_addr.s_addr == INADDR_ANY) {
2440 #ifdef INET6
2441                                         /*
2442                                          * We use O_FORWARD_IP opcode for
2443                                          * fwd rule with tablearg, but tables
2444                                          * now support IPv6 addresses. And
2445                                          * when we are inspecting IPv6 packet,
2446                                          * we can use nh6 field from
2447                                          * table_value as next_hop6 address.
2448                                          */
2449                                         if (is_ipv6) {
2450                                                 struct sockaddr_in6 *sa6;
2451
2452                                                 sa6 = args->next_hop6 =
2453                                                     &args->hopstore6;
2454                                                 sa6->sin6_family = AF_INET6;
2455                                                 sa6->sin6_len = sizeof(*sa6);
2456                                                 sa6->sin6_addr = TARG_VAL(
2457                                                     chain, tablearg, nh6);
2458                                                 sa6->sin6_port = sa->sin_port;
2459                                                 /*
2460                                                  * Set sin6_scope_id only for
2461                                                  * link-local unicast addresses.
2462                                                  */
2463                                                 if (IN6_IS_ADDR_LINKLOCAL(
2464                                                     &sa6->sin6_addr))
2465                                                         sa6->sin6_scope_id =
2466                                                             TARG_VAL(chain,
2467                                                                 tablearg,
2468                                                                 zoneid);
2469                                         } else
2470 #endif
2471                                         {
2472                                                 args->hopstore.sin_port =
2473                                                     sa->sin_port;
2474                                                 sa = args->next_hop =
2475                                                     &args->hopstore;
2476                                                 sa->sin_family = AF_INET;
2477                                                 sa->sin_len = sizeof(*sa);
2478                                                 sa->sin_addr.s_addr = htonl(
2479                                                     TARG_VAL(chain, tablearg,
2480                                                     nh4));
2481                                         }
2482                                     } else {
2483                                         args->next_hop = sa;
2484                                     }
2485                                 }
2486                                 retval = IP_FW_PASS;
2487                                 l = 0;          /* exit inner loop */
2488                                 done = 1;       /* exit outer loop */
2489                                 break;
2490
2491 #ifdef INET6
2492                         case O_FORWARD_IP6:
2493                                 if (args->eh)   /* not valid on layer2 pkts */
2494                                         break;
2495                                 if (q == NULL || q->rule != f ||
2496                                     dyn_dir == MATCH_FORWARD) {
2497                                         struct sockaddr_in6 *sin6;
2498
2499                                         sin6 = &(((ipfw_insn_sa6 *)cmd)->sa);
2500                                         args->next_hop6 = sin6;
2501                                 }
2502                                 retval = IP_FW_PASS;
2503                                 l = 0;          /* exit inner loop */
2504                                 done = 1;       /* exit outer loop */
2505                                 break;
2506 #endif
2507
2508                         case O_NETGRAPH:
2509                         case O_NGTEE:
2510                                 set_match(args, f_pos, chain);
2511                                 args->rule.info = TARG(cmd->arg1, netgraph);
2512                                 if (V_fw_one_pass)
2513                                         args->rule.info |= IPFW_ONEPASS;
2514                                 retval = (cmd->opcode == O_NETGRAPH) ?
2515                                     IP_FW_NETGRAPH : IP_FW_NGTEE;
2516                                 l = 0;          /* exit inner loop */
2517                                 done = 1;       /* exit outer loop */
2518                                 break;
2519
2520                         case O_SETFIB: {
2521                                 uint32_t fib;
2522
2523                                 IPFW_INC_RULE_COUNTER(f, pktlen);
2524                                 fib = TARG(cmd->arg1, fib) & 0x7FFF;
2525                                 if (fib >= rt_numfibs)
2526                                         fib = 0;
2527                                 M_SETFIB(m, fib);
2528                                 args->f_id.fib = fib;
2529                                 l = 0;          /* exit inner loop */
2530                                 break;
2531                         }
2532
2533                         case O_SETDSCP: {
2534                                 uint16_t code;
2535
2536                                 code = TARG(cmd->arg1, dscp) & 0x3F;
2537                                 l = 0;          /* exit inner loop */
2538                                 if (is_ipv4) {
2539                                         uint16_t old;
2540
2541                                         old = *(uint16_t *)ip;
2542                                         ip->ip_tos = (code << 2) |
2543                                             (ip->ip_tos & 0x03);
2544                                         ip->ip_sum = cksum_adjust(ip->ip_sum,
2545                                             old, *(uint16_t *)ip);
2546                                 } else if (is_ipv6) {
2547                                         uint8_t *v;
2548
2549                                         v = &((struct ip6_hdr *)ip)->ip6_vfc;
2550                                         *v = (*v & 0xF0) | (code >> 2);
2551                                         v++;
2552                                         *v = (*v & 0x3F) | ((code & 0x03) << 6);
2553                                 } else
2554                                         break;
2555
2556                                 IPFW_INC_RULE_COUNTER(f, pktlen);
2557                                 break;
2558                         }
2559
2560                         case O_NAT:
2561                                 l = 0;          /* exit inner loop */
2562                                 done = 1;       /* exit outer loop */
2563                                 /*
2564                                  * Ensure that we do not invoke NAT handler for
2565                                  * non IPv4 packets. Libalias expects only IPv4.
2566                                  */
2567                                 if (!is_ipv4 || !IPFW_NAT_LOADED) {
2568                                     retval = IP_FW_DENY;
2569                                     break;
2570                                 }
2571
2572                                 struct cfg_nat *t;
2573                                 int nat_id;
2574
2575                                 set_match(args, f_pos, chain);
2576                                 /* Check if this is 'global' nat rule */
2577                                 if (cmd->arg1 == IP_FW_NAT44_GLOBAL) {
2578                                         retval = ipfw_nat_ptr(args, NULL, m);
2579                                         break;
2580                                 }
2581                                 t = ((ipfw_insn_nat *)cmd)->nat;
2582                                 if (t == NULL) {
2583                                         nat_id = TARG(cmd->arg1, nat);
2584                                         t = (*lookup_nat_ptr)(&chain->nat, nat_id);
2585
2586                                         if (t == NULL) {
2587                                             retval = IP_FW_DENY;
2588                                             break;
2589                                         }
2590                                         if (cmd->arg1 != IP_FW_TARG)
2591                                             ((ipfw_insn_nat *)cmd)->nat = t;
2592                                 }
2593                                 retval = ipfw_nat_ptr(args, t, m);
2594                                 break;
2595
2596                         case O_REASS: {
2597                                 int ip_off;
2598
2599                                 IPFW_INC_RULE_COUNTER(f, pktlen);
2600                                 l = 0;  /* in any case exit inner loop */
2601                                 ip_off = ntohs(ip->ip_off);
2602
2603                                 /* if not fragmented, go to next rule */
2604                                 if ((ip_off & (IP_MF | IP_OFFMASK)) == 0)
2605                                     break;
2606
2607                                 args->m = m = ip_reass(m);
2608
2609                                 /*
2610                                  * do IP header checksum fixup.
2611                                  */
2612                                 if (m == NULL) { /* fragment got swallowed */
2613                                     retval = IP_FW_DENY;
2614                                 } else { /* good, packet complete */
2615                                     int hlen;
2616
2617                                     ip = mtod(m, struct ip *);
2618                                     hlen = ip->ip_hl << 2;
2619                                     ip->ip_sum = 0;
2620                                     if (hlen == sizeof(struct ip))
2621                                         ip->ip_sum = in_cksum_hdr(ip);
2622                                     else
2623                                         ip->ip_sum = in_cksum(m, hlen);
2624                                     retval = IP_FW_REASS;
2625                                     set_match(args, f_pos, chain);
2626                                 }
2627                                 done = 1;       /* exit outer loop */
2628                                 break;
2629                         }
2630                         case O_EXTERNAL_ACTION:
2631                                 l = 0; /* in any case exit inner loop */
2632                                 retval = ipfw_run_eaction(chain, args,
2633                                     cmd, &done);
2634                                 /*
2635                                  * If both @retval and @done are zero,
2636                                  * consider this as rule matching and
2637                                  * update counters.
2638                                  */
2639                                 if (retval == 0 && done == 0) {
2640                                         IPFW_INC_RULE_COUNTER(f, pktlen);
2641                                         /*
2642                                          * Reset the result of the last
2643                                          * dynamic state lookup.
2644                                          * External action can change
2645                                          * @args content, and it may be
2646                                          * used for new state lookup later.
2647                                          */
2648                                         dyn_dir = MATCH_UNKNOWN;
2649                                 }
2650                                 break;
2651
2652                         default:
2653                                 panic("-- unknown opcode %d\n", cmd->opcode);
2654                         } /* end of switch() on opcodes */
2655                         /*
2656                          * if we get here with l=0, then match is irrelevant.
2657                          */
2658
2659                         if (cmd->len & F_NOT)
2660                                 match = !match;
2661
2662                         if (match) {
2663                                 if (cmd->len & F_OR)
2664                                         skip_or = 1;
2665                         } else {
2666                                 if (!(cmd->len & F_OR)) /* not an OR block, */
2667                                         break;          /* try next rule    */
2668                         }
2669
2670                 }       /* end of inner loop, scan opcodes */
2671 #undef PULLUP_LEN
2672
2673                 if (done)
2674                         break;
2675
2676 /* next_rule:; */       /* try next rule                */
2677
2678         }               /* end of outer for, scan rules */
2679
2680         if (done) {
2681                 struct ip_fw *rule = chain->map[f_pos];
2682                 /* Update statistics */
2683                 IPFW_INC_RULE_COUNTER(rule, pktlen);
2684         } else {
2685                 retval = IP_FW_DENY;
2686                 printf("ipfw: ouch!, skip past end of rules, denying packet\n");
2687         }
2688         IPFW_PF_RUNLOCK(chain);
2689 #ifdef __FreeBSD__
2690         if (ucred_cache != NULL)
2691                 crfree(ucred_cache);
2692 #endif
2693         return (retval);
2694
2695 pullup_failed:
2696         if (V_fw_verbose)
2697                 printf("ipfw: pullup failed\n");
2698         return (IP_FW_DENY);
2699 }
2700
2701 /*
2702  * Set maximum number of tables that can be used in given VNET ipfw instance.
2703  */
2704 #ifdef SYSCTL_NODE
2705 static int
2706 sysctl_ipfw_table_num(SYSCTL_HANDLER_ARGS)
2707 {
2708         int error;
2709         unsigned int ntables;
2710
2711         ntables = V_fw_tables_max;
2712
2713         error = sysctl_handle_int(oidp, &ntables, 0, req);
2714         /* Read operation or some error */
2715         if ((error != 0) || (req->newptr == NULL))
2716                 return (error);
2717
2718         return (ipfw_resize_tables(&V_layer3_chain, ntables));
2719 }
2720
2721 /*
2722  * Switches table namespace between global and per-set.
2723  */
2724 static int
2725 sysctl_ipfw_tables_sets(SYSCTL_HANDLER_ARGS)
2726 {
2727         int error;
2728         unsigned int sets;
2729
2730         sets = V_fw_tables_sets;
2731
2732         error = sysctl_handle_int(oidp, &sets, 0, req);
2733         /* Read operation or some error */
2734         if ((error != 0) || (req->newptr == NULL))
2735                 return (error);
2736
2737         return (ipfw_switch_tables_namespace(&V_layer3_chain, sets));
2738 }
2739 #endif
2740
2741 /*
2742  * Module and VNET glue
2743  */
2744
2745 /*
2746  * Stuff that must be initialised only on boot or module load
2747  */
2748 static int
2749 ipfw_init(void)
2750 {
2751         int error = 0;
2752
2753         /*
2754          * Only print out this stuff the first time around,
2755          * when called from the sysinit code.
2756          */
2757         printf("ipfw2 "
2758 #ifdef INET6
2759                 "(+ipv6) "
2760 #endif
2761                 "initialized, divert %s, nat %s, "
2762                 "default to %s, logging ",
2763 #ifdef IPDIVERT
2764                 "enabled",
2765 #else
2766                 "loadable",
2767 #endif
2768 #ifdef IPFIREWALL_NAT
2769                 "enabled",
2770 #else
2771                 "loadable",
2772 #endif
2773                 default_to_accept ? "accept" : "deny");
2774
2775         /*
2776          * Note: V_xxx variables can be accessed here but the vnet specific
2777          * initializer may not have been called yet for the VIMAGE case.
2778          * Tuneables will have been processed. We will print out values for
2779          * the default vnet.
2780          * XXX This should all be rationalized AFTER 8.0
2781          */
2782         if (V_fw_verbose == 0)
2783                 printf("disabled\n");
2784         else if (V_verbose_limit == 0)
2785                 printf("unlimited\n");
2786         else
2787                 printf("limited to %d packets/entry by default\n",
2788                     V_verbose_limit);
2789
2790         /* Check user-supplied table count for validness */
2791         if (default_fw_tables > IPFW_TABLES_MAX)
2792           default_fw_tables = IPFW_TABLES_MAX;
2793
2794         ipfw_init_sopt_handler();
2795         ipfw_init_obj_rewriter();
2796         ipfw_iface_init();
2797         return (error);
2798 }
2799
2800 /*
2801  * Called for the removal of the last instance only on module unload.
2802  */
2803 static void
2804 ipfw_destroy(void)
2805 {
2806
2807         ipfw_iface_destroy();
2808         ipfw_destroy_sopt_handler();
2809         ipfw_destroy_obj_rewriter();
2810         printf("IP firewall unloaded\n");
2811 }
2812
2813 /*
2814  * Stuff that must be initialized for every instance
2815  * (including the first of course).
2816  */
2817 static int
2818 vnet_ipfw_init(const void *unused)
2819 {
2820         int error, first;
2821         struct ip_fw *rule = NULL;
2822         struct ip_fw_chain *chain;
2823
2824         chain = &V_layer3_chain;
2825
2826         first = IS_DEFAULT_VNET(curvnet) ? 1 : 0;
2827
2828         /* First set up some values that are compile time options */
2829         V_autoinc_step = 100;   /* bounded to 1..1000 in add_rule() */
2830         V_fw_deny_unknown_exthdrs = 1;
2831 #ifdef IPFIREWALL_VERBOSE
2832         V_fw_verbose = 1;
2833 #endif
2834 #ifdef IPFIREWALL_VERBOSE_LIMIT
2835         V_verbose_limit = IPFIREWALL_VERBOSE_LIMIT;
2836 #endif
2837 #ifdef IPFIREWALL_NAT
2838         LIST_INIT(&chain->nat);
2839 #endif
2840
2841         /* Init shared services hash table */
2842         ipfw_init_srv(chain);
2843
2844         ipfw_init_counters();
2845         /* insert the default rule and create the initial map */
2846         chain->n_rules = 1;
2847         chain->map = malloc(sizeof(struct ip_fw *), M_IPFW, M_WAITOK | M_ZERO);
2848         rule = ipfw_alloc_rule(chain, sizeof(struct ip_fw));
2849
2850         /* Set initial number of tables */
2851         V_fw_tables_max = default_fw_tables;
2852         error = ipfw_init_tables(chain, first);
2853         if (error) {
2854                 printf("ipfw2: setting up tables failed\n");
2855                 free(chain->map, M_IPFW);
2856                 free(rule, M_IPFW);
2857                 return (ENOSPC);
2858         }
2859
2860         /* fill and insert the default rule */
2861         rule->act_ofs = 0;
2862         rule->rulenum = IPFW_DEFAULT_RULE;
2863         rule->cmd_len = 1;
2864         rule->set = RESVD_SET;
2865         rule->cmd[0].len = 1;
2866         rule->cmd[0].opcode = default_to_accept ? O_ACCEPT : O_DENY;
2867         chain->default_rule = chain->map[0] = rule;
2868         chain->id = rule->id = 1;
2869         /* Pre-calculate rules length for legacy dump format */
2870         chain->static_len = sizeof(struct ip_fw_rule0);
2871
2872         IPFW_LOCK_INIT(chain);
2873         ipfw_dyn_init(chain);
2874         ipfw_eaction_init(chain, first);
2875 #ifdef LINEAR_SKIPTO
2876         ipfw_init_skipto_cache(chain);
2877 #endif
2878         ipfw_bpf_init(first);
2879
2880         /* First set up some values that are compile time options */
2881         V_ipfw_vnet_ready = 1;          /* Open for business */
2882
2883         /*
2884          * Hook the sockopt handler and pfil hooks for ipv4 and ipv6.
2885          * Even if the latter two fail we still keep the module alive
2886          * because the sockopt and layer2 paths are still useful.
2887          * ipfw[6]_hook return 0 on success, ENOENT on failure,
2888          * so we can ignore the exact return value and just set a flag.
2889          *
2890          * Note that V_fw[6]_enable are manipulated by a SYSCTL_PROC so
2891          * changes in the underlying (per-vnet) variables trigger
2892          * immediate hook()/unhook() calls.
2893          * In layer2 we have the same behaviour, except that V_ether_ipfw
2894          * is checked on each packet because there are no pfil hooks.
2895          */
2896         V_ip_fw_ctl_ptr = ipfw_ctl3;
2897         error = ipfw_attach_hooks(1);
2898         return (error);
2899 }
2900
2901 /*
2902  * Called for the removal of each instance.
2903  */
2904 static int
2905 vnet_ipfw_uninit(const void *unused)
2906 {
2907         struct ip_fw *reap;
2908         struct ip_fw_chain *chain = &V_layer3_chain;
2909         int i, last;
2910
2911         V_ipfw_vnet_ready = 0; /* tell new callers to go away */
2912         /*
2913          * disconnect from ipv4, ipv6, layer2 and sockopt.
2914          * Then grab, release and grab again the WLOCK so we make
2915          * sure the update is propagated and nobody will be in.
2916          */
2917         (void)ipfw_attach_hooks(0 /* detach */);
2918         V_ip_fw_ctl_ptr = NULL;
2919
2920         last = IS_DEFAULT_VNET(curvnet) ? 1 : 0;
2921
2922         IPFW_UH_WLOCK(chain);
2923         IPFW_UH_WUNLOCK(chain);
2924
2925         ipfw_dyn_uninit(0);     /* run the callout_drain */
2926
2927         IPFW_UH_WLOCK(chain);
2928
2929         reap = NULL;
2930         IPFW_WLOCK(chain);
2931         for (i = 0; i < chain->n_rules; i++)
2932                 ipfw_reap_add(chain, &reap, chain->map[i]);
2933         free(chain->map, M_IPFW);
2934 #ifdef LINEAR_SKIPTO
2935         ipfw_destroy_skipto_cache(chain);
2936 #endif
2937         IPFW_WUNLOCK(chain);
2938         IPFW_UH_WUNLOCK(chain);
2939         ipfw_destroy_tables(chain, last);
2940         ipfw_eaction_uninit(chain, last);
2941         if (reap != NULL)
2942                 ipfw_reap_rules(reap);
2943         vnet_ipfw_iface_destroy(chain);
2944         ipfw_destroy_srv(chain);
2945         IPFW_LOCK_DESTROY(chain);
2946         ipfw_dyn_uninit(1);     /* free the remaining parts */
2947         ipfw_destroy_counters();
2948         ipfw_bpf_uninit(last);
2949         return (0);
2950 }
2951
2952 /*
2953  * Module event handler.
2954  * In general we have the choice of handling most of these events by the
2955  * event handler or by the (VNET_)SYS(UN)INIT handlers. I have chosen to
2956  * use the SYSINIT handlers as they are more capable of expressing the
2957  * flow of control during module and vnet operations, so this is just
2958  * a skeleton. Note there is no SYSINIT equivalent of the module
2959  * SHUTDOWN handler, but we don't have anything to do in that case anyhow.
2960  */
2961 static int
2962 ipfw_modevent(module_t mod, int type, void *unused)
2963 {
2964         int err = 0;
2965
2966         switch (type) {
2967         case MOD_LOAD:
2968                 /* Called once at module load or
2969                  * system boot if compiled in. */
2970                 break;
2971         case MOD_QUIESCE:
2972                 /* Called before unload. May veto unloading. */
2973                 break;
2974         case MOD_UNLOAD:
2975                 /* Called during unload. */
2976                 break;
2977         case MOD_SHUTDOWN:
2978                 /* Called during system shutdown. */
2979                 break;
2980         default:
2981                 err = EOPNOTSUPP;
2982                 break;
2983         }
2984         return err;
2985 }
2986
2987 static moduledata_t ipfwmod = {
2988         "ipfw",
2989         ipfw_modevent,
2990         0
2991 };
2992
2993 /* Define startup order. */
2994 #define IPFW_SI_SUB_FIREWALL    SI_SUB_PROTO_FIREWALL
2995 #define IPFW_MODEVENT_ORDER     (SI_ORDER_ANY - 255) /* On boot slot in here. */
2996 #define IPFW_MODULE_ORDER       (IPFW_MODEVENT_ORDER + 1) /* A little later. */
2997 #define IPFW_VNET_ORDER         (IPFW_MODEVENT_ORDER + 2) /* Later still. */
2998
2999 DECLARE_MODULE(ipfw, ipfwmod, IPFW_SI_SUB_FIREWALL, IPFW_MODEVENT_ORDER);
3000 FEATURE(ipfw_ctl3, "ipfw new sockopt calls");
3001 MODULE_VERSION(ipfw, 3);
3002 /* should declare some dependencies here */
3003
3004 /*
3005  * Starting up. Done in order after ipfwmod() has been called.
3006  * VNET_SYSINIT is also called for each existing vnet and each new vnet.
3007  */
3008 SYSINIT(ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER,
3009             ipfw_init, NULL);
3010 VNET_SYSINIT(vnet_ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER,
3011             vnet_ipfw_init, NULL);
3012
3013 /*
3014  * Closing up shop. These are done in REVERSE ORDER, but still
3015  * after ipfwmod() has been called. Not called on reboot.
3016  * VNET_SYSUNINIT is also called for each exiting vnet as it exits.
3017  * or when the module is unloaded.
3018  */
3019 SYSUNINIT(ipfw_destroy, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER,
3020             ipfw_destroy, NULL);
3021 VNET_SYSUNINIT(vnet_ipfw_uninit, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER,
3022             vnet_ipfw_uninit, NULL);
3023 /* end of file */