sys/netpfil/ipfw/ip_fw2.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 /*
  32  * The FreeBSD IP packet firewall, main file
  33  */
  34
  35 #include "opt_ipfw.h"
  36 #include "opt_ipdivert.h"
  37 #include "opt_inet.h"
  38 #ifndef INET
  39 #error "IPFIREWALL requires INET"
  40 #endif /* INET */
  41 #include "opt_inet6.h"
  42
  43 #include <sys/param.h>
  44 #include <sys/systm.h>
  45 #include <sys/condvar.h>
  46 #include <sys/counter.h>
  47 #include <sys/eventhandler.h>
  48 #include <sys/malloc.h>
  49 #include <sys/mbuf.h>
  50 #include <sys/kernel.h>
  51 #include <sys/lock.h>
  52 #include <sys/jail.h>
  53 #include <sys/module.h>
  54 #include <sys/priv.h>
  55 #include <sys/proc.h>
  56 #include <sys/rwlock.h>
  57 #include <sys/rmlock.h>
  58 #include <sys/sdt.h>
  59 #include <sys/socket.h>
  60 #include <sys/socketvar.h>
  61 #include <sys/sysctl.h>
  62 #include <sys/syslog.h>
  63 #include <sys/ucred.h>
  64 #include <net/ethernet.h> /* for ETHERTYPE_IP */
  65 #include <net/if.h>
  66 #include <net/if_var.h>
  67 #include <net/route.h>
  68 #include <net/route/nhop.h>
  69 #include <net/pfil.h>
  70 #include <net/vnet.h>
  71
  72 #include <netpfil/pf/pf_mtag.h>
  73
  74 #include <netinet/in.h>
  75 #include <netinet/in_var.h>
  76 #include <netinet/in_pcb.h>
  77 #include <netinet/ip.h>
  78 #include <netinet/ip_var.h>
  79 #include <netinet/ip_icmp.h>
  80 #include <netinet/ip_fw.h>
  81 #include <netinet/ip_carp.h>
  82 #include <netinet/pim.h>
  83 #include <netinet/tcp_var.h>
  84 #include <netinet/udp.h>
  85 #include <netinet/udp_var.h>
  86 #include <netinet/sctp.h>
  87 #include <netinet/sctp_crc32.h>
  88 #include <netinet/sctp_header.h>
  89
  90 #include <netinet/ip6.h>
  91 #include <netinet/icmp6.h>
  92 #include <netinet/in_fib.h>
  93 #ifdef INET6
  94 #include <netinet6/in6_fib.h>
  95 #include <netinet6/in6_pcb.h>
  96 #include <netinet6/scope6_var.h>
  97 #include <netinet6/ip6_var.h>
  98 #endif
  99
 100 #include <net/if_gre.h> /* for struct grehdr */
 101
 102 #include <netpfil/ipfw/ip_fw_private.h>
 103
 104 #include <machine/in_cksum.h>   /* XXX for in_cksum */
 105
 106 #ifdef MAC
 107 #include <security/mac/mac_framework.h>
 108 #endif
 109
 110 #define IPFW_PROBE(probe, arg0, arg1, arg2, arg3, arg4, arg5)           \
 111     SDT_PROBE6(ipfw, , , probe, arg0, arg1, arg2, arg3, arg4, arg5)
 112
 113 SDT_PROVIDER_DEFINE(ipfw);
 114 SDT_PROBE_DEFINE6(ipfw, , , rule__matched,
 115     "int",                      /* retval */
 116     "int",                      /* af */
 117     "void *",                   /* src addr */
 118     "void *",                   /* dst addr */
 119     "struct ip_fw_args *",      /* args */
 120     "struct ip_fw *"            /* rule */);
 121
 122 /*
 123  * static variables followed by global ones.
 124  * All ipfw global variables are here.
 125  */
 126
 127 VNET_DEFINE_STATIC(int, fw_deny_unknown_exthdrs);
 128 #define V_fw_deny_unknown_exthdrs       VNET(fw_deny_unknown_exthdrs)
 129
 130 VNET_DEFINE_STATIC(int, fw_permit_single_frag6) = 1;
 131 #define V_fw_permit_single_frag6        VNET(fw_permit_single_frag6)
 132
 133 #ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
 134 static int default_to_accept = 1;
 135 #else
 136 static int default_to_accept;
 137 #endif
 138
 139 VNET_DEFINE(int, autoinc_step);
 140 VNET_DEFINE(int, fw_one_pass) = 1;
 141
 142 VNET_DEFINE(unsigned int, fw_tables_max);
 143 VNET_DEFINE(unsigned int, fw_tables_sets) = 0;  /* Don't use set-aware tables */
 144 /* Use 128 tables by default */
 145 static unsigned int default_fw_tables = IPFW_TABLES_DEFAULT;
 146
 147 static int jump_lookup_pos(struct ip_fw_chain *chain, struct ip_fw *f, int num,
 148     int tablearg, int jump_backwards);
 149 #ifndef LINEAR_SKIPTO
 150 static int jump_cached(struct ip_fw_chain *chain, struct ip_fw *f, int num,
 151     int tablearg, int jump_backwards);
 152 #define JUMP(ch, f, num, targ, back)    jump_cached(ch, f, num, targ, back)
 153 #else
 154 #define JUMP(ch, f, num, targ, back)    jump_lookup_pos(ch, f, num, targ, back)
 155 #endif
 156
 157 /*
 158  * Each rule belongs to one of 32 different sets (0..31).
 159  * The variable set_disable contains one bit per set.
 160  * If the bit is set, all rules in the corresponding set
 161  * are disabled. Set RESVD_SET(31) is reserved for the default rule
 162  * and rules that are not deleted by the flush command,
 163  * and CANNOT be disabled.
 164  * Rules in set RESVD_SET can only be deleted individually.
 165  */
 166 VNET_DEFINE(u_int32_t, set_disable);
 167 #define V_set_disable                   VNET(set_disable)
 168
 169 VNET_DEFINE(int, fw_verbose);
 170 /* counter for ipfw_log(NULL...) */
 171 VNET_DEFINE(u_int64_t, norule_counter);
 172 VNET_DEFINE(int, verbose_limit);
 173
 174 /* layer3_chain contains the list of rules for layer 3 */
 175 VNET_DEFINE(struct ip_fw_chain, layer3_chain);
 176
 177 /* ipfw_vnet_ready controls when we are open for business */
 178 VNET_DEFINE(int, ipfw_vnet_ready) = 0;
 179
 180 VNET_DEFINE(int, ipfw_nat_ready) = 0;
 181
 182 ipfw_nat_t *ipfw_nat_ptr = NULL;
 183 struct cfg_nat *(*lookup_nat_ptr)(struct nat_list *, int);
 184 ipfw_nat_cfg_t *ipfw_nat_cfg_ptr;
 185 ipfw_nat_cfg_t *ipfw_nat_del_ptr;
 186 ipfw_nat_cfg_t *ipfw_nat_get_cfg_ptr;
 187 ipfw_nat_cfg_t *ipfw_nat_get_log_ptr;
 188
 189 #ifdef SYSCTL_NODE
 190 uint32_t dummy_def = IPFW_DEFAULT_RULE;
 191 static int sysctl_ipfw_table_num(SYSCTL_HANDLER_ARGS);
 192 static int sysctl_ipfw_tables_sets(SYSCTL_HANDLER_ARGS);
 193
 194 SYSBEGIN(f3)
 195
 196 SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
 197     "Firewall");
 198 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, one_pass,
 199     CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_one_pass), 0,
 200     "Only do a single pass through ipfw when using dummynet(4)");
 201 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, autoinc_step,
 202     CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(autoinc_step), 0,
 203     "Rule number auto-increment step");
 204 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose,
 205     CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_verbose), 0,
 206     "Log matches to ipfw rules");
 207 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit,
 208     CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(verbose_limit), 0,
 209     "Set upper limit of matches of ipfw rules logged");
 210 SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, default_rule, CTLFLAG_RD,
 211     &dummy_def, 0,
 212     "The default/max possible rule number.");
 213 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, tables_max,
 214     CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE,
 215     0, 0, sysctl_ipfw_table_num, "IU",
 216     "Maximum number of concurrently used tables");
 217 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, tables_sets,
 218     CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE,
 219     0, 0, sysctl_ipfw_tables_sets, "IU",
 220     "Use per-set namespace for tables");
 221 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, default_to_accept, CTLFLAG_RDTUN,
 222     &default_to_accept, 0,
 223     "Make the default rule accept all packets.");
 224 TUNABLE_INT("net.inet.ip.fw.tables_max", (int *)&default_fw_tables);
 225 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, static_count,
 226     CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(layer3_chain.n_rules), 0,
 227     "Number of static rules");
 228
 229 #ifdef INET6
 230 SYSCTL_DECL(_net_inet6_ip6);
 231 SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, fw, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
 232     "Firewall");
 233 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, deny_unknown_exthdrs,
 234     CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE,
 235     &VNET_NAME(fw_deny_unknown_exthdrs), 0,
 236     "Deny packets with unknown IPv6 Extension Headers");
 237 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, permit_single_frag6,
 238     CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE,
 239     &VNET_NAME(fw_permit_single_frag6), 0,
 240     "Permit single packet IPv6 fragments");
 241 #endif /* INET6 */
 242
 243 SYSEND
 244
 245 #endif /* SYSCTL_NODE */
 246
 247 /*
 248  * Some macros used in the various matching options.
 249  * L3HDR maps an ipv4 pointer into a layer3 header pointer of type T
 250  * Other macros just cast void * into the appropriate type
 251  */
 252 #define L3HDR(T, ip)    ((T *)((u_int32_t *)(ip) + (ip)->ip_hl))
 253 #define TCP(p)          ((struct tcphdr *)(p))
 254 #define SCTP(p)         ((struct sctphdr *)(p))
 255 #define UDP(p)          ((struct udphdr *)(p))
 256 #define ICMP(p)         ((struct icmphdr *)(p))
 257 #define ICMP6(p)        ((struct icmp6_hdr *)(p))
 258
 259 static __inline int
 260 icmptype_match(struct icmphdr *icmp, ipfw_insn_u32 *cmd)
 261 {
 262         int type = icmp->icmp_type;
 263
 264         return (type <= ICMP_MAXTYPE && (cmd->d[0] & (1<<type)) );
 265 }
 266
 267 #define TT      ( (1 << ICMP_ECHO) | (1 << ICMP_ROUTERSOLICIT) | \
 268     (1 << ICMP_TSTAMP) | (1 << ICMP_IREQ) | (1 << ICMP_MASKREQ) )
 269
 270 static int
 271 is_icmp_query(struct icmphdr *icmp)
 272 {
 273         int type = icmp->icmp_type;
 274
 275         return (type <= ICMP_MAXTYPE && (TT & (1<<type)) );
 276 }
 277 #undef TT
 278
 279 /*
 280  * The following checks use two arrays of 8 or 16 bits to store the
 281  * bits that we want set or clear, respectively. They are in the
 282  * low and high half of cmd->arg1 or cmd->d[0].
 283  *
 284  * We scan options and store the bits we find set. We succeed if
 285  *
 286  *      (want_set & ~bits) == 0 && (want_clear & ~bits) == want_clear
 287  *
 288  * The code is sometimes optimized not to store additional variables.
 289  */
 290
 291 static int
 292 flags_match(ipfw_insn *cmd, u_int8_t bits)
 293 {
 294         u_char want_clear;
 295         bits = ~bits;
 296
 297         if ( ((cmd->arg1 & 0xff) & bits) != 0)
 298                 return 0; /* some bits we want set were clear */
 299         want_clear = (cmd->arg1 >> 8) & 0xff;
 300         if ( (want_clear & bits) != want_clear)
 301                 return 0; /* some bits we want clear were set */
 302         return 1;
 303 }
 304
 305 static int
 306 ipopts_match(struct ip *ip, ipfw_insn *cmd)
 307 {
 308         int optlen, bits = 0;
 309         u_char *cp = (u_char *)(ip + 1);
 310         int x = (ip->ip_hl << 2) - sizeof (struct ip);
 311
 312         for (; x > 0; x -= optlen, cp += optlen) {
 313                 int opt = cp[IPOPT_OPTVAL];
 314
 315                 if (opt == IPOPT_EOL)
 316                         break;
 317                 if (opt == IPOPT_NOP)
 318                         optlen = 1;
 319                 else {
 320                         optlen = cp[IPOPT_OLEN];
 321                         if (optlen <= 0 || optlen > x)
 322                                 return 0; /* invalid or truncated */
 323                 }
 324                 switch (opt) {
 325                 default:
 326                         break;
 327
 328                 case IPOPT_LSRR:
 329                         bits |= IP_FW_IPOPT_LSRR;
 330                         break;
 331
 332                 case IPOPT_SSRR:
 333                         bits |= IP_FW_IPOPT_SSRR;
 334                         break;
 335
 336                 case IPOPT_RR:
 337                         bits |= IP_FW_IPOPT_RR;
 338                         break;
 339
 340                 case IPOPT_TS:
 341                         bits |= IP_FW_IPOPT_TS;
 342                         break;
 343                 }
 344         }
 345         return (flags_match(cmd, bits));
 346 }
 347
 348 /*
 349  * Parse TCP options. The logic copied from tcp_dooptions().
 350  */
 351 static int
 352 tcpopts_parse(const struct tcphdr *tcp, uint16_t *mss)
 353 {
 354         const u_char *cp = (const u_char *)(tcp + 1);
 355         int optlen, bits = 0;
 356         int cnt = (tcp->th_off << 2) - sizeof(struct tcphdr);
 357
 358         for (; cnt > 0; cnt -= optlen, cp += optlen) {
 359                 int opt = cp[0];
 360                 if (opt == TCPOPT_EOL)
 361                         break;
 362                 if (opt == TCPOPT_NOP)
 363                         optlen = 1;
 364                 else {
 365                         if (cnt < 2)
 366                                 break;
 367                         optlen = cp[1];
 368                         if (optlen < 2 || optlen > cnt)
 369                                 break;
 370                 }
 371
 372                 switch (opt) {
 373                 default:
 374                         break;
 375
 376                 case TCPOPT_MAXSEG:
 377                         if (optlen != TCPOLEN_MAXSEG)
 378                                 break;
 379                         bits |= IP_FW_TCPOPT_MSS;
 380                         if (mss != NULL)
 381                                 *mss = be16dec(cp + 2);
 382                         break;
 383
 384                 case TCPOPT_WINDOW:
 385                         if (optlen == TCPOLEN_WINDOW)
 386                                 bits |= IP_FW_TCPOPT_WINDOW;
 387                         break;
 388
 389                 case TCPOPT_SACK_PERMITTED:
 390                         if (optlen == TCPOLEN_SACK_PERMITTED)
 391                                 bits |= IP_FW_TCPOPT_SACK;
 392                         break;
 393
 394                 case TCPOPT_SACK:
 395                         if (optlen > 2 && (optlen - 2) % TCPOLEN_SACK == 0)
 396                                 bits |= IP_FW_TCPOPT_SACK;
 397                         break;
 398
 399                 case TCPOPT_TIMESTAMP:
 400                         if (optlen == TCPOLEN_TIMESTAMP)
 401                                 bits |= IP_FW_TCPOPT_TS;
 402                         break;
 403                 }
 404         }
 405         return (bits);
 406 }
 407
 408 static int
 409 tcpopts_match(struct tcphdr *tcp, ipfw_insn *cmd)
 410 {
 411
 412         return (flags_match(cmd, tcpopts_parse(tcp, NULL)));
 413 }
 414
 415 static int
 416 iface_match(struct ifnet *ifp, ipfw_insn_if *cmd, struct ip_fw_chain *chain,
 417     uint32_t *tablearg)
 418 {
 419
 420         if (ifp == NULL)        /* no iface with this packet, match fails */
 421                 return (0);
 422
 423         /* Check by name or by IP address */
 424         if (cmd->name[0] != '\0') { /* match by name */
 425                 if (cmd->name[0] == '\1') /* use tablearg to match */
 426                         return ipfw_lookup_table(chain, cmd->p.kidx, 0,
 427                             &ifp->if_index, tablearg);
 428                 /* Check name */
 429                 if (cmd->p.glob) {
 430                         if (fnmatch(cmd->name, ifp->if_xname, 0) == 0)
 431                                 return(1);
 432                 } else {
 433                         if (strncmp(ifp->if_xname, cmd->name, IFNAMSIZ) == 0)
 434                                 return(1);
 435                 }
 436         } else {
 437 #if !defined(USERSPACE) && defined(__FreeBSD__) /* and OSX too ? */
 438                 struct ifaddr *ia;
 439
 440                 NET_EPOCH_ASSERT();
 441
 442                 CK_STAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) {
 443                         if (ia->ifa_addr->sa_family != AF_INET)
 444                                 continue;
 445                         if (cmd->p.ip.s_addr == ((struct sockaddr_in *)
 446                             (ia->ifa_addr))->sin_addr.s_addr)
 447                                 return (1);     /* match */
 448                 }
 449 #endif /* __FreeBSD__ */
 450         }
 451         return(0);      /* no match, fail ... */
 452 }
 453
 454 /*
 455  * The verify_path function checks if a route to the src exists and
 456  * if it is reachable via ifp (when provided).
 457  *
 458  * The 'verrevpath' option checks that the interface that an IP packet
 459  * arrives on is the same interface that traffic destined for the
 460  * packet's source address would be routed out of.
 461  * The 'versrcreach' option just checks that the source address is
 462  * reachable via any route (except default) in the routing table.
 463  * These two are a measure to block forged packets. This is also
 464  * commonly known as "anti-spoofing" or Unicast Reverse Path
 465  * Forwarding (Unicast RFP) in Cisco-ese. The name of the knobs
 466  * is purposely reminiscent of the Cisco IOS command,
 467  *
 468  *   ip verify unicast reverse-path
 469  *   ip verify unicast source reachable-via any
 470  *
 471  * which implements the same functionality. But note that the syntax
 472  * is misleading, and the check may be performed on all IP packets
 473  * whether unicast, multicast, or broadcast.
 474  */
 475 static int
 476 verify_path(struct in_addr src, struct ifnet *ifp, u_int fib)
 477 {
 478 #if defined(USERSPACE) || !defined(__FreeBSD__)
 479         return 0;
 480 #else
 481         struct nhop_object *nh;
 482
 483         nh = fib4_lookup(fib, src, 0, NHR_NONE, 0);
 484         if (nh == NULL)
 485                 return (0);
 486
 487         /*
 488          * If ifp is provided, check for equality with rtentry.
 489          * We should use rt->rt_ifa->ifa_ifp, instead of rt->rt_ifp,
 490          * in order to pass packets injected back by if_simloop():
 491          * routing entry (via lo0) for our own address
 492          * may exist, so we need to handle routing assymetry.
 493          */
 494         if (ifp != NULL && ifp != nh->nh_aifp)
 495                 return (0);
 496
 497         /* if no ifp provided, check if rtentry is not default route */
 498         if (ifp == NULL && (nh->nh_flags & NHF_DEFAULT) != 0)
 499                 return (0);
 500
 501         /* or if this is a blackhole/reject route */
 502         if (ifp == NULL && (nh->nh_flags & (NHF_REJECT|NHF_BLACKHOLE)) != 0)
 503                 return (0);
 504
 505         /* found valid route */
 506         return 1;
 507 #endif /* __FreeBSD__ */
 508 }
 509
 510 /*
 511  * Generate an SCTP packet containing an ABORT chunk. The verification tag
 512  * is given by vtag. The T-bit is set in the ABORT chunk if and only if
 513  * reflected is not 0.
 514  */
 515
 516 static struct mbuf *
 517 ipfw_send_abort(struct mbuf *replyto, struct ipfw_flow_id *id, u_int32_t vtag,
 518     int reflected)
 519 {
 520         struct mbuf *m;
 521         struct ip *ip;
 522 #ifdef INET6
 523         struct ip6_hdr *ip6;
 524 #endif
 525         struct sctphdr *sctp;
 526         struct sctp_chunkhdr *chunk;
 527         u_int16_t hlen, plen, tlen;
 528
 529         MGETHDR(m, M_NOWAIT, MT_DATA);
 530         if (m == NULL)
 531                 return (NULL);
 532
 533         M_SETFIB(m, id->fib);
 534 #ifdef MAC
 535         if (replyto != NULL)
 536                 mac_netinet_firewall_reply(replyto, m);
 537         else
 538                 mac_netinet_firewall_send(m);
 539 #else
 540         (void)replyto;          /* don't warn about unused arg */
 541 #endif
 542
 543         switch (id->addr_type) {
 544         case 4:
 545                 hlen = sizeof(struct ip);
 546                 break;
 547 #ifdef INET6
 548         case 6:
 549                 hlen = sizeof(struct ip6_hdr);
 550                 break;
 551 #endif
 552         default:
 553                 /* XXX: log me?!? */
 554                 FREE_PKT(m);
 555                 return (NULL);
 556         }
 557         plen = sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr);
 558         tlen = hlen + plen;
 559         m->m_data += max_linkhdr;
 560         m->m_flags |= M_SKIP_FIREWALL;
 561         m->m_pkthdr.len = m->m_len = tlen;
 562         m->m_pkthdr.rcvif = NULL;
 563         bzero(m->m_data, tlen);
 564
 565         switch (id->addr_type) {
 566         case 4:
 567                 ip = mtod(m, struct ip *);
 568
 569                 ip->ip_v = 4;
 570                 ip->ip_hl = sizeof(struct ip) >> 2;
 571                 ip->ip_tos = IPTOS_LOWDELAY;
 572                 ip->ip_len = htons(tlen);
 573                 ip->ip_id = htons(0);
 574                 ip->ip_off = htons(0);
 575                 ip->ip_ttl = V_ip_defttl;
 576                 ip->ip_p = IPPROTO_SCTP;
 577                 ip->ip_sum = 0;
 578                 ip->ip_src.s_addr = htonl(id->dst_ip);
 579                 ip->ip_dst.s_addr = htonl(id->src_ip);
 580
 581                 sctp = (struct sctphdr *)(ip + 1);
 582                 break;
 583 #ifdef INET6
 584         case 6:
 585                 ip6 = mtod(m, struct ip6_hdr *);
 586
 587                 ip6->ip6_vfc = IPV6_VERSION;
 588                 ip6->ip6_plen = htons(plen);
 589                 ip6->ip6_nxt = IPPROTO_SCTP;
 590                 ip6->ip6_hlim = IPV6_DEFHLIM;
 591                 ip6->ip6_src = id->dst_ip6;
 592                 ip6->ip6_dst = id->src_ip6;
 593
 594                 sctp = (struct sctphdr *)(ip6 + 1);
 595                 break;
 596 #endif
 597         }
 598
 599         sctp->src_port = htons(id->dst_port);
 600         sctp->dest_port = htons(id->src_port);
 601         sctp->v_tag = htonl(vtag);
 602         sctp->checksum = htonl(0);
 603
 604         chunk = (struct sctp_chunkhdr *)(sctp + 1);
 605         chunk->chunk_type = SCTP_ABORT_ASSOCIATION;
 606         chunk->chunk_flags = 0;
 607         if (reflected != 0) {
 608                 chunk->chunk_flags |= SCTP_HAD_NO_TCB;
 609         }
 610         chunk->chunk_length = htons(sizeof(struct sctp_chunkhdr));
 611
 612         sctp->checksum = sctp_calculate_cksum(m, hlen);
 613
 614         return (m);
 615 }
 616
 617 /*
 618  * Generate a TCP packet, containing either a RST or a keepalive.
 619  * When flags & TH_RST, we are sending a RST packet, because of a
 620  * "reset" action matched the packet.
 621  * Otherwise we are sending a keepalive, and flags & TH_
 622  * The 'replyto' mbuf is the mbuf being replied to, if any, and is required
 623  * so that MAC can label the reply appropriately.
 624  */
 625 struct mbuf *
 626 ipfw_send_pkt(struct mbuf *replyto, struct ipfw_flow_id *id, u_int32_t seq,
 627     u_int32_t ack, int flags)
 628 {
 629         struct mbuf *m = NULL;          /* stupid compiler */
 630         struct ip *h = NULL;            /* stupid compiler */
 631 #ifdef INET6
 632         struct ip6_hdr *h6 = NULL;
 633 #endif
 634         struct tcphdr *th = NULL;
 635         int len, dir;
 636
 637         MGETHDR(m, M_NOWAIT, MT_DATA);
 638         if (m == NULL)
 639                 return (NULL);
 640
 641         M_SETFIB(m, id->fib);
 642 #ifdef MAC
 643         if (replyto != NULL)
 644                 mac_netinet_firewall_reply(replyto, m);
 645         else
 646                 mac_netinet_firewall_send(m);
 647 #else
 648         (void)replyto;          /* don't warn about unused arg */
 649 #endif
 650
 651         switch (id->addr_type) {
 652         case 4:
 653                 len = sizeof(struct ip) + sizeof(struct tcphdr);
 654                 break;
 655 #ifdef INET6
 656         case 6:
 657                 len = sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
 658                 break;
 659 #endif
 660         default:
 661                 /* XXX: log me?!? */
 662                 FREE_PKT(m);
 663                 return (NULL);
 664         }
 665         dir = ((flags & (TH_SYN | TH_RST)) == TH_SYN);
 666
 667         m->m_data += max_linkhdr;
 668         m->m_flags |= M_SKIP_FIREWALL;
 669         m->m_pkthdr.len = m->m_len = len;
 670         m->m_pkthdr.rcvif = NULL;
 671         bzero(m->m_data, len);
 672
 673         switch (id->addr_type) {
 674         case 4:
 675                 h = mtod(m, struct ip *);
 676
 677                 /* prepare for checksum */
 678                 h->ip_p = IPPROTO_TCP;
 679                 h->ip_len = htons(sizeof(struct tcphdr));
 680                 if (dir) {
 681                         h->ip_src.s_addr = htonl(id->src_ip);
 682                         h->ip_dst.s_addr = htonl(id->dst_ip);
 683                 } else {
 684                         h->ip_src.s_addr = htonl(id->dst_ip);
 685                         h->ip_dst.s_addr = htonl(id->src_ip);
 686                 }
 687
 688                 th = (struct tcphdr *)(h + 1);
 689                 break;
 690 #ifdef INET6
 691         case 6:
 692                 h6 = mtod(m, struct ip6_hdr *);
 693
 694                 /* prepare for checksum */
 695                 h6->ip6_nxt = IPPROTO_TCP;
 696                 h6->ip6_plen = htons(sizeof(struct tcphdr));
 697                 if (dir) {
 698                         h6->ip6_src = id->src_ip6;
 699                         h6->ip6_dst = id->dst_ip6;
 700                 } else {
 701                         h6->ip6_src = id->dst_ip6;
 702                         h6->ip6_dst = id->src_ip6;
 703                 }
 704
 705                 th = (struct tcphdr *)(h6 + 1);
 706                 break;
 707 #endif
 708         }
 709
 710         if (dir) {
 711                 th->th_sport = htons(id->src_port);
 712                 th->th_dport = htons(id->dst_port);
 713         } else {
 714                 th->th_sport = htons(id->dst_port);
 715                 th->th_dport = htons(id->src_port);
 716         }
 717         th->th_off = sizeof(struct tcphdr) >> 2;
 718
 719         if (flags & TH_RST) {
 720                 if (flags & TH_ACK) {
 721                         th->th_seq = htonl(ack);
 722                         th->th_flags = TH_RST;
 723                 } else {
 724                         if (flags & TH_SYN)
 725                                 seq++;
 726                         th->th_ack = htonl(seq);
 727                         th->th_flags = TH_RST | TH_ACK;
 728                 }
 729         } else {
 730                 /*
 731                  * Keepalive - use caller provided sequence numbers
 732                  */
 733                 th->th_seq = htonl(seq);
 734                 th->th_ack = htonl(ack);
 735                 th->th_flags = TH_ACK;
 736         }
 737
 738         switch (id->addr_type) {
 739         case 4:
 740                 th->th_sum = in_cksum(m, len);
 741
 742                 /* finish the ip header */
 743                 h->ip_v = 4;
 744                 h->ip_hl = sizeof(*h) >> 2;
 745                 h->ip_tos = IPTOS_LOWDELAY;
 746                 h->ip_off = htons(0);
 747                 h->ip_len = htons(len);
 748                 h->ip_ttl = V_ip_defttl;
 749                 h->ip_sum = 0;
 750                 break;
 751 #ifdef INET6
 752         case 6:
 753                 th->th_sum = in6_cksum(m, IPPROTO_TCP, sizeof(*h6),
 754                     sizeof(struct tcphdr));
 755
 756                 /* finish the ip6 header */
 757                 h6->ip6_vfc |= IPV6_VERSION;
 758                 h6->ip6_hlim = IPV6_DEFHLIM;
 759                 break;
 760 #endif
 761         }
 762
 763         return (m);
 764 }
 765
 766 #ifdef INET6
 767 /*
 768  * ipv6 specific rules here...
 769  */
 770 static __inline int
 771 icmp6type_match(int type, ipfw_insn_u32 *cmd)
 772 {
 773         return (type <= ICMP6_MAXTYPE && (cmd->d[type/32] & (1<<(type%32)) ) );
 774 }
 775
 776 static int
 777 flow6id_match(int curr_flow, ipfw_insn_u32 *cmd)
 778 {
 779         int i;
 780         for (i=0; i <= cmd->o.arg1; ++i)
 781                 if (curr_flow == cmd->d[i])
 782                         return 1;
 783         return 0;
 784 }
 785
 786 /* support for IP6_*_ME opcodes */
 787 static const struct in6_addr lla_mask = {{{
 788         0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff,
 789         0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
 790 }}};
 791
 792 static int
 793 ipfw_localip6(struct in6_addr *in6)
 794 {
 795         struct rm_priotracker in6_ifa_tracker;
 796         struct in6_ifaddr *ia;
 797
 798         if (IN6_IS_ADDR_MULTICAST(in6))
 799                 return (0);
 800
 801         if (!IN6_IS_ADDR_LINKLOCAL(in6))
 802                 return (in6_localip(in6));
 803
 804         IN6_IFADDR_RLOCK(&in6_ifa_tracker);
 805         CK_STAILQ_FOREACH(ia, &V_in6_ifaddrhead, ia_link) {
 806                 if (!IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr))
 807                         continue;
 808                 if (IN6_ARE_MASKED_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
 809                     in6, &lla_mask)) {
 810                         IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
 811                         return (1);
 812                 }
 813         }
 814         IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
 815         return (0);
 816 }
 817
 818 static int
 819 verify_path6(struct in6_addr *src, struct ifnet *ifp, u_int fib)
 820 {
 821         struct nhop_object *nh;
 822
 823         if (IN6_IS_SCOPE_LINKLOCAL(src))
 824                 return (1);
 825
 826         nh = fib6_lookup(fib, src, 0, NHR_NONE, 0);
 827         if (nh == NULL)
 828                 return (0);
 829
 830         /* If ifp is provided, check for equality with route table. */
 831         if (ifp != NULL && ifp != nh->nh_aifp)
 832                 return (0);
 833
 834         /* if no ifp provided, check if rtentry is not default route */
 835         if (ifp == NULL && (nh->nh_flags & NHF_DEFAULT) != 0)
 836                 return (0);
 837
 838         /* or if this is a blackhole/reject route */
 839         if (ifp == NULL && (nh->nh_flags & (NHF_REJECT|NHF_BLACKHOLE)) != 0)
 840                 return (0);
 841
 842         /* found valid route */
 843         return 1;
 844 }
 845
 846 static int
 847 is_icmp6_query(int icmp6_type)
 848 {
 849         if ((icmp6_type <= ICMP6_MAXTYPE) &&
 850             (icmp6_type == ICMP6_ECHO_REQUEST ||
 851             icmp6_type == ICMP6_MEMBERSHIP_QUERY ||
 852             icmp6_type == ICMP6_WRUREQUEST ||
 853             icmp6_type == ICMP6_FQDN_QUERY ||
 854             icmp6_type == ICMP6_NI_QUERY))
 855                 return (1);
 856
 857         return (0);
 858 }
 859
 860 static int
 861 map_icmp_unreach(int code)
 862 {
 863
 864         /* RFC 7915 p4.2 */
 865         switch (code) {
 866         case ICMP_UNREACH_NET:
 867         case ICMP_UNREACH_HOST:
 868         case ICMP_UNREACH_SRCFAIL:
 869         case ICMP_UNREACH_NET_UNKNOWN:
 870         case ICMP_UNREACH_HOST_UNKNOWN:
 871         case ICMP_UNREACH_TOSNET:
 872         case ICMP_UNREACH_TOSHOST:
 873                 return (ICMP6_DST_UNREACH_NOROUTE);
 874         case ICMP_UNREACH_PORT:
 875                 return (ICMP6_DST_UNREACH_NOPORT);
 876         default:
 877                 /*
 878                  * Map the rest of codes into admit prohibited.
 879                  * XXX: unreach proto should be mapped into ICMPv6
 880                  * parameter problem, but we use only unreach type.
 881                  */
 882                 return (ICMP6_DST_UNREACH_ADMIN);
 883         }
 884 }
 885
 886 static void
 887 send_reject6(struct ip_fw_args *args, int code, u_int hlen, struct ip6_hdr *ip6)
 888 {
 889         struct mbuf *m;
 890
 891         m = args->m;
 892         if (code == ICMP6_UNREACH_RST && args->f_id.proto == IPPROTO_TCP) {
 893                 struct tcphdr *tcp;
 894                 tcp = (struct tcphdr *)((char *)ip6 + hlen);
 895
 896                 if ((tcp->th_flags & TH_RST) == 0) {
 897                         struct mbuf *m0;
 898                         m0 = ipfw_send_pkt(args->m, &(args->f_id),
 899                             ntohl(tcp->th_seq), ntohl(tcp->th_ack),
 900                             tcp->th_flags | TH_RST);
 901                         if (m0 != NULL)
 902                                 ip6_output(m0, NULL, NULL, 0, NULL, NULL,
 903                                     NULL);
 904                 }
 905                 FREE_PKT(m);
 906         } else if (code == ICMP6_UNREACH_ABORT &&
 907             args->f_id.proto == IPPROTO_SCTP) {
 908                 struct mbuf *m0;
 909                 struct sctphdr *sctp;
 910                 u_int32_t v_tag;
 911                 int reflected;
 912
 913                 sctp = (struct sctphdr *)((char *)ip6 + hlen);
 914                 reflected = 1;
 915                 v_tag = ntohl(sctp->v_tag);
 916                 /* Investigate the first chunk header if available */
 917                 if (m->m_len >= hlen + sizeof(struct sctphdr) +
 918                     sizeof(struct sctp_chunkhdr)) {
 919                         struct sctp_chunkhdr *chunk;
 920
 921                         chunk = (struct sctp_chunkhdr *)(sctp + 1);
 922                         switch (chunk->chunk_type) {
 923                         case SCTP_INITIATION:
 924                                 /*
 925                                  * Packets containing an INIT chunk MUST have
 926                                  * a zero v-tag.
 927                                  */
 928                                 if (v_tag != 0) {
 929                                         v_tag = 0;
 930                                         break;
 931                                 }
 932                                 /* INIT chunk MUST NOT be bundled */
 933                                 if (m->m_pkthdr.len >
 934                                     hlen + sizeof(struct sctphdr) +
 935                                     ntohs(chunk->chunk_length) + 3) {
 936                                         break;
 937                                 }
 938                                 /* Use the initiate tag if available */
 939                                 if ((m->m_len >= hlen + sizeof(struct sctphdr) +
 940                                     sizeof(struct sctp_chunkhdr) +
 941                                     offsetof(struct sctp_init, a_rwnd))) {
 942                                         struct sctp_init *init;
 943
 944                                         init = (struct sctp_init *)(chunk + 1);
 945                                         v_tag = ntohl(init->initiate_tag);
 946                                         reflected = 0;
 947                                 }
 948                                 break;
 949                         case SCTP_ABORT_ASSOCIATION:
 950                                 /*
 951                                  * If the packet contains an ABORT chunk, don't
 952                                  * reply.
 953                                  * XXX: We should search through all chunks,
 954                                  * but do not do that to avoid attacks.
 955                                  */
 956                                 v_tag = 0;
 957                                 break;
 958                         }
 959                 }
 960                 if (v_tag == 0) {
 961                         m0 = NULL;
 962                 } else {
 963                         m0 = ipfw_send_abort(args->m, &(args->f_id), v_tag,
 964                             reflected);
 965                 }
 966                 if (m0 != NULL)
 967                         ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL);
 968                 FREE_PKT(m);
 969         } else if (code != ICMP6_UNREACH_RST && code != ICMP6_UNREACH_ABORT) {
 970                 /* Send an ICMPv6 unreach. */
 971 #if 0
 972                 /*
 973                  * Unlike above, the mbufs need to line up with the ip6 hdr,
 974                  * as the contents are read. We need to m_adj() the
 975                  * needed amount.
 976                  * The mbuf will however be thrown away so we can adjust it.
 977                  * Remember we did an m_pullup on it already so we
 978                  * can make some assumptions about contiguousness.
 979                  */
 980                 if (args->L3offset)
 981                         m_adj(m, args->L3offset);
 982 #endif
 983                 icmp6_error(m, ICMP6_DST_UNREACH, code, 0);
 984         } else
 985                 FREE_PKT(m);
 986
 987         args->m = NULL;
 988 }
 989
 990 #endif /* INET6 */
 991
 992 /*
 993  * sends a reject message, consuming the mbuf passed as an argument.
 994  */
 995 static void
 996 send_reject(struct ip_fw_args *args, int code, int iplen, struct ip *ip)
 997 {
 998
 999 #if 0
1000         /* XXX When ip is not guaranteed to be at mtod() we will
1001          * need to account for this */
1002          * The mbuf will however be thrown away so we can adjust it.
1003          * Remember we did an m_pullup on it already so we
1004          * can make some assumptions about contiguousness.
1005          */
1006         if (args->L3offset)
1007                 m_adj(m, args->L3offset);
1008 #endif
1009         if (code != ICMP_REJECT_RST && code != ICMP_REJECT_ABORT) {
1010                 /* Send an ICMP unreach */
1011                 icmp_error(args->m, ICMP_UNREACH, code, 0L, 0);
1012         } else if (code == ICMP_REJECT_RST && args->f_id.proto == IPPROTO_TCP) {
1013                 struct tcphdr *const tcp =
1014                     L3HDR(struct tcphdr, mtod(args->m, struct ip *));
1015                 if ( (tcp->th_flags & TH_RST) == 0) {
1016                         struct mbuf *m;
1017                         m = ipfw_send_pkt(args->m, &(args->f_id),
1018                                 ntohl(tcp->th_seq), ntohl(tcp->th_ack),
1019                                 tcp->th_flags | TH_RST);
1020                         if (m != NULL)
1021                                 ip_output(m, NULL, NULL, 0, NULL, NULL);
1022                 }
1023                 FREE_PKT(args->m);
1024         } else if (code == ICMP_REJECT_ABORT &&
1025             args->f_id.proto == IPPROTO_SCTP) {
1026                 struct mbuf *m;
1027                 struct sctphdr *sctp;
1028                 struct sctp_chunkhdr *chunk;
1029                 struct sctp_init *init;
1030                 u_int32_t v_tag;
1031                 int reflected;
1032
1033                 sctp = L3HDR(struct sctphdr, mtod(args->m, struct ip *));
1034                 reflected = 1;
1035                 v_tag = ntohl(sctp->v_tag);
1036                 if (iplen >= (ip->ip_hl << 2) + sizeof(struct sctphdr) +
1037                     sizeof(struct sctp_chunkhdr)) {
1038                         /* Look at the first chunk header if available */
1039                         chunk = (struct sctp_chunkhdr *)(sctp + 1);
1040                         switch (chunk->chunk_type) {
1041                         case SCTP_INITIATION:
1042                                 /*
1043                                  * Packets containing an INIT chunk MUST have
1044                                  * a zero v-tag.
1045                                  */
1046                                 if (v_tag != 0) {
1047                                         v_tag = 0;
1048                                         break;
1049                                 }
1050                                 /* INIT chunk MUST NOT be bundled */
1051                                 if (iplen >
1052                                     (ip->ip_hl << 2) + sizeof(struct sctphdr) +
1053                                     ntohs(chunk->chunk_length) + 3) {
1054                                         break;
1055                                 }
1056                                 /* Use the initiate tag if available */
1057                                 if ((iplen >= (ip->ip_hl << 2) +
1058                                     sizeof(struct sctphdr) +
1059                                     sizeof(struct sctp_chunkhdr) +
1060                                     offsetof(struct sctp_init, a_rwnd))) {
1061                                         init = (struct sctp_init *)(chunk + 1);
1062                                         v_tag = ntohl(init->initiate_tag);
1063                                         reflected = 0;
1064                                 }
1065                                 break;
1066                         case SCTP_ABORT_ASSOCIATION:
1067                                 /*
1068                                  * If the packet contains an ABORT chunk, don't
1069                                  * reply.
1070                                  * XXX: We should search through all chunks,
1071                                  * but do not do that to avoid attacks.
1072                                  */
1073                                 v_tag = 0;
1074                                 break;
1075                         }
1076                 }
1077                 if (v_tag == 0) {
1078                         m = NULL;
1079                 } else {
1080                         m = ipfw_send_abort(args->m, &(args->f_id), v_tag,
1081                             reflected);
1082                 }
1083                 if (m != NULL)
1084                         ip_output(m, NULL, NULL, 0, NULL, NULL);
1085                 FREE_PKT(args->m);
1086         } else
1087                 FREE_PKT(args->m);
1088         args->m = NULL;
1089 }
1090
1091 /*
1092  * Support for uid/gid/jail lookup. These tests are expensive
1093  * (because we may need to look into the list of active sockets)
1094  * so we cache the results. ugid_lookupp is 0 if we have not
1095  * yet done a lookup, 1 if we succeeded, and -1 if we tried
1096  * and failed. The function always returns the match value.
1097  * We could actually spare the variable and use *uc, setting
1098  * it to '(void *)check_uidgid if we have no info, NULL if
1099  * we tried and failed, or any other value if successful.
1100  */
1101 static int
1102 check_uidgid(ipfw_insn_u32 *insn, struct ip_fw_args *args, int *ugid_lookupp,
1103     struct ucred **uc)
1104 {
1105 #if defined(USERSPACE)
1106         return 0;       // not supported in userspace
1107 #else
1108 #ifndef __FreeBSD__
1109         /* XXX */
1110         return cred_check(insn, proto, oif,
1111             dst_ip, dst_port, src_ip, src_port,
1112             (struct bsd_ucred *)uc, ugid_lookupp, ((struct mbuf *)inp)->m_skb);
1113 #else  /* FreeBSD */
1114         struct in_addr src_ip, dst_ip;
1115         struct inpcbinfo *pi;
1116         struct ipfw_flow_id *id;
1117         struct inpcb *pcb, *inp;
1118         int lookupflags;
1119         int match;
1120
1121         id = &args->f_id;
1122         inp = args->inp;
1123
1124         /*
1125          * Check to see if the UDP or TCP stack supplied us with
1126          * the PCB. If so, rather then holding a lock and looking
1127          * up the PCB, we can use the one that was supplied.
1128          */
1129         if (inp && *ugid_lookupp == 0) {
1130                 INP_LOCK_ASSERT(inp);
1131                 if (inp->inp_socket != NULL) {
1132                         *uc = crhold(inp->inp_cred);
1133                         *ugid_lookupp = 1;
1134                 } else
1135                         *ugid_lookupp = -1;
1136         }
1137         /*
1138          * If we have already been here and the packet has no
1139          * PCB entry associated with it, then we can safely
1140          * assume that this is a no match.
1141          */
1142         if (*ugid_lookupp == -1)
1143                 return (0);
1144         if (id->proto == IPPROTO_TCP) {
1145                 lookupflags = 0;
1146                 pi = &V_tcbinfo;
1147         } else if (id->proto == IPPROTO_UDP) {
1148                 lookupflags = INPLOOKUP_WILDCARD;
1149                 pi = &V_udbinfo;
1150         } else if (id->proto == IPPROTO_UDPLITE) {
1151                 lookupflags = INPLOOKUP_WILDCARD;
1152                 pi = &V_ulitecbinfo;
1153         } else
1154                 return 0;
1155         lookupflags |= INPLOOKUP_RLOCKPCB;
1156         match = 0;
1157         if (*ugid_lookupp == 0) {
1158                 if (id->addr_type == 6) {
1159 #ifdef INET6
1160                         if (args->flags & IPFW_ARGS_IN)
1161                                 pcb = in6_pcblookup_mbuf(pi,
1162                                     &id->src_ip6, htons(id->src_port),
1163                                     &id->dst_ip6, htons(id->dst_port),
1164                                     lookupflags, NULL, args->m);
1165                         else
1166                                 pcb = in6_pcblookup_mbuf(pi,
1167                                     &id->dst_ip6, htons(id->dst_port),
1168                                     &id->src_ip6, htons(id->src_port),
1169                                     lookupflags, args->ifp, args->m);
1170 #else
1171                         *ugid_lookupp = -1;
1172                         return (0);
1173 #endif
1174                 } else {
1175                         src_ip.s_addr = htonl(id->src_ip);
1176                         dst_ip.s_addr = htonl(id->dst_ip);
1177                         if (args->flags & IPFW_ARGS_IN)
1178                                 pcb = in_pcblookup_mbuf(pi,
1179                                     src_ip, htons(id->src_port),
1180                                     dst_ip, htons(id->dst_port),
1181                                     lookupflags, NULL, args->m);
1182                         else
1183                                 pcb = in_pcblookup_mbuf(pi,
1184                                     dst_ip, htons(id->dst_port),
1185                                     src_ip, htons(id->src_port),
1186                                     lookupflags, args->ifp, args->m);
1187                 }
1188                 if (pcb != NULL) {
1189                         INP_RLOCK_ASSERT(pcb);
1190                         *uc = crhold(pcb->inp_cred);
1191                         *ugid_lookupp = 1;
1192                         INP_RUNLOCK(pcb);
1193                 }
1194                 if (*ugid_lookupp == 0) {
1195                         /*
1196                          * We tried and failed, set the variable to -1
1197                          * so we will not try again on this packet.
1198                          */
1199                         *ugid_lookupp = -1;
1200                         return (0);
1201                 }
1202         }
1203         if (insn->o.opcode == O_UID)
1204                 match = ((*uc)->cr_uid == (uid_t)insn->d[0]);
1205         else if (insn->o.opcode == O_GID)
1206                 match = groupmember((gid_t)insn->d[0], *uc);
1207         else if (insn->o.opcode == O_JAIL)
1208                 match = ((*uc)->cr_prison->pr_id == (int)insn->d[0]);
1209         return (match);
1210 #endif /* __FreeBSD__ */
1211 #endif /* not supported in userspace */
1212 }
1213
1214 /*
1215  * Helper function to set args with info on the rule after the matching
1216  * one. slot is precise, whereas we guess rule_id as they are
1217  * assigned sequentially.
1218  */
1219 static inline void
1220 set_match(struct ip_fw_args *args, int slot,
1221         struct ip_fw_chain *chain)
1222 {
1223         args->rule.chain_id = chain->id;
1224         args->rule.slot = slot + 1; /* we use 0 as a marker */
1225         args->rule.rule_id = 1 + chain->map[slot]->id;
1226         args->rule.rulenum = chain->map[slot]->rulenum;
1227         args->flags |= IPFW_ARGS_REF;
1228 }
1229
1230 static int
1231 jump_lookup_pos(struct ip_fw_chain *chain, struct ip_fw *f, int num,
1232     int tablearg, int jump_backwards)
1233 {
1234         int f_pos, i;
1235
1236         i = IP_FW_ARG_TABLEARG(chain, num, skipto);
1237         /* make sure we do not jump backward */
1238         if (jump_backwards == 0 && i <= f->rulenum)
1239                 i = f->rulenum + 1;
1240
1241 #ifndef LINEAR_SKIPTO
1242         if (chain->idxmap != NULL)
1243                 f_pos = chain->idxmap[i];
1244         else
1245                 f_pos = ipfw_find_rule(chain, i, 0);
1246 #else
1247         f_pos = chain->idxmap[i];
1248 #endif /* LINEAR_SKIPTO */
1249
1250         return (f_pos);
1251 }
1252
1253
1254 #ifndef LINEAR_SKIPTO
1255 /*
1256  * Helper function to enable cached rule lookups using
1257  * cache.id and cache.pos fields in ipfw rule.
1258  */
1259 static int
1260 jump_cached(struct ip_fw_chain *chain, struct ip_fw *f, int num,
1261     int tablearg, int jump_backwards)
1262 {
1263         int f_pos;
1264
1265         /* Can't use cache with IP_FW_TARG */
1266         if (num == IP_FW_TARG)
1267                 return jump_lookup_pos(chain, f, num, tablearg, jump_backwards);
1268
1269         /*
1270          * If possible use cached f_pos (in f->cache.pos),
1271          * whose version is written in f->cache.id (horrible hacks
1272          * to avoid changing the ABI).
1273          *
1274          * Multiple threads can execute the same rule simultaneously,
1275          * we need to ensure that cache.pos is updated before cache.id.
1276          */
1277
1278 #ifdef __LP64__
1279         struct ip_fw_jump_cache cache;
1280
1281         cache.raw_value = f->cache.raw_value;
1282         if (cache.id == chain->id)
1283                 return (cache.pos);
1284
1285         f_pos = jump_lookup_pos(chain, f, num, tablearg, jump_backwards);
1286
1287         cache.pos = f_pos;
1288         cache.id = chain->id;
1289         f->cache.raw_value = cache.raw_value;
1290 #else
1291         if (f->cache.id == chain->id) {
1292                 /* Load pos after id */
1293                 atomic_thread_fence_acq();
1294                 return (f->cache.pos);
1295         }
1296
1297         f_pos = jump_lookup_pos(chain, f, num, tablearg, jump_backwards);
1298
1299         f->cache.pos = f_pos;
1300         /* Store id after pos */
1301         atomic_thread_fence_rel();
1302         f->cache.id = chain->id;
1303 #endif /* !__LP64__ */
1304         return (f_pos);
1305 }
1306 #endif /* !LINEAR_SKIPTO */
1307
1308 #define TARG(k, f)      IP_FW_ARG_TABLEARG(chain, k, f)
1309 /*
1310  * The main check routine for the firewall.
1311  *
1312  * All arguments are in args so we can modify them and return them
1313  * back to the caller.
1314  *
1315  * Parameters:
1316  *
1317  *      args->m (in/out) The packet; we set to NULL when/if we nuke it.
1318  *              Starts with the IP header.
1319  *      args->L3offset  Number of bytes bypassed if we came from L2.
1320  *                      e.g. often sizeof(eh)  ** NOTYET **
1321  *      args->ifp       Incoming or outgoing interface.
1322  *      args->divert_rule (in/out)
1323  *              Skip up to the first rule past this rule number;
1324  *              upon return, non-zero port number for divert or tee.
1325  *
1326  *      args->rule      Pointer to the last matching rule (in/out)
1327  *      args->next_hop  Socket we are forwarding to (out).
1328  *      args->next_hop6 IPv6 next hop we are forwarding to (out).
1329  *      args->f_id      Addresses grabbed from the packet (out)
1330  *      args->rule.info a cookie depending on rule action
1331  *
1332  * Return value:
1333  *
1334  *      IP_FW_PASS      the packet must be accepted
1335  *      IP_FW_DENY      the packet must be dropped
1336  *      IP_FW_DIVERT    divert packet, port in m_tag
1337  *      IP_FW_TEE       tee packet, port in m_tag
1338  *      IP_FW_DUMMYNET  to dummynet, pipe in args->cookie
1339  *      IP_FW_NETGRAPH  into netgraph, cookie args->cookie
1340  *              args->rule contains the matching rule,
1341  *              args->rule.info has additional information.
1342  *
1343  */
1344 int
1345 ipfw_chk(struct ip_fw_args *args)
1346 {
1347
1348         /*
1349          * Local variables holding state while processing a packet:
1350          *
1351          * IMPORTANT NOTE: to speed up the processing of rules, there
1352          * are some assumption on the values of the variables, which
1353          * are documented here. Should you change them, please check
1354          * the implementation of the various instructions to make sure
1355          * that they still work.
1356          *
1357          * m | args->m  Pointer to the mbuf, as received from the caller.
1358          *      It may change if ipfw_chk() does an m_pullup, or if it
1359          *      consumes the packet because it calls send_reject().
1360          *      XXX This has to change, so that ipfw_chk() never modifies
1361          *      or consumes the buffer.
1362          *      OR
1363          * args->mem    Pointer to contigous memory chunk.
1364          * ip   Is the beginning of the ip(4 or 6) header.
1365          * eh   Ethernet header in case if input is Layer2.
1366          */
1367         struct mbuf *m;
1368         struct ip *ip;
1369         struct ether_header *eh;
1370
1371         /*
1372          * For rules which contain uid/gid or jail constraints, cache
1373          * a copy of the users credentials after the pcb lookup has been
1374          * executed. This will speed up the processing of rules with
1375          * these types of constraints, as well as decrease contention
1376          * on pcb related locks.
1377          */
1378 #ifndef __FreeBSD__
1379         struct bsd_ucred ucred_cache;
1380 #else
1381         struct ucred *ucred_cache = NULL;
1382 #endif
1383         int ucred_lookup = 0;
1384         int f_pos = 0;          /* index of current rule in the array */
1385         int retval = 0;
1386         struct ifnet *oif, *iif;
1387
1388         /*
1389          * hlen The length of the IP header.
1390          */
1391         u_int hlen = 0;         /* hlen >0 means we have an IP pkt */
1392
1393         /*
1394          * offset       The offset of a fragment. offset != 0 means that
1395          *      we have a fragment at this offset of an IPv4 packet.
1396          *      offset == 0 means that (if this is an IPv4 packet)
1397          *      this is the first or only fragment.
1398          *      For IPv6 offset|ip6f_mf == 0 means there is no Fragment Header
1399          *      or there is a single packet fragment (fragment header added
1400          *      without needed).  We will treat a single packet fragment as if
1401          *      there was no fragment header (or log/block depending on the
1402          *      V_fw_permit_single_frag6 sysctl setting).
1403          */
1404         u_short offset = 0;
1405         u_short ip6f_mf = 0;
1406
1407         /*
1408          * Local copies of addresses. They are only valid if we have
1409          * an IP packet.
1410          *
1411          * proto        The protocol. Set to 0 for non-ip packets,
1412          *      or to the protocol read from the packet otherwise.
1413          *      proto != 0 means that we have an IPv4 packet.
1414          *
1415          * src_port, dst_port   port numbers, in HOST format. Only
1416          *      valid for TCP and UDP packets.
1417          *
1418          * src_ip, dst_ip       ip addresses, in NETWORK format.
1419          *      Only valid for IPv4 packets.
1420          */
1421         uint8_t proto;
1422         uint16_t src_port, dst_port;            /* NOTE: host format    */
1423         struct in_addr src_ip, dst_ip;          /* NOTE: network format */
1424         int iplen = 0;
1425         int pktlen;
1426
1427         struct ipfw_dyn_info dyn_info;
1428         struct ip_fw *q = NULL;
1429         struct ip_fw_chain *chain = &V_layer3_chain;
1430
1431         /*
1432          * We store in ulp a pointer to the upper layer protocol header.
1433          * In the ipv4 case this is easy to determine from the header,
1434          * but for ipv6 we might have some additional headers in the middle.
1435          * ulp is NULL if not found.
1436          */
1437         void *ulp = NULL;               /* upper layer protocol pointer. */
1438
1439         /* XXX ipv6 variables */
1440         int is_ipv6 = 0;
1441         uint8_t icmp6_type = 0;
1442         uint16_t ext_hd = 0;    /* bits vector for extension header filtering */
1443         /* end of ipv6 variables */
1444
1445         int is_ipv4 = 0;
1446
1447         int done = 0;           /* flag to exit the outer loop */
1448         IPFW_RLOCK_TRACKER;
1449         bool mem;
1450
1451         if ((mem = (args->flags & IPFW_ARGS_LENMASK))) {
1452                 if (args->flags & IPFW_ARGS_ETHER) {
1453                         eh = (struct ether_header *)args->mem;
1454                         if (eh->ether_type == htons(ETHERTYPE_VLAN))
1455                                 ip = (struct ip *)
1456                                     ((struct ether_vlan_header *)eh + 1);
1457                         else
1458                                 ip = (struct ip *)(eh + 1);
1459                 } else {
1460                         eh = NULL;
1461                         ip = (struct ip *)args->mem;
1462                 }
1463                 pktlen = IPFW_ARGS_LENGTH(args->flags);
1464                 args->f_id.fib = args->ifp->if_fib;     /* best guess */
1465         } else {
1466                 m = args->m;
1467                 if (m->m_flags & M_SKIP_FIREWALL || (! V_ipfw_vnet_ready))
1468                         return (IP_FW_PASS);    /* accept */
1469                 if (args->flags & IPFW_ARGS_ETHER) {
1470                         /* We need some amount of data to be contiguous. */
1471                         if (m->m_len < min(m->m_pkthdr.len, max_protohdr) &&
1472                             (args->m = m = m_pullup(m, min(m->m_pkthdr.len,
1473                             max_protohdr))) == NULL)
1474                                 goto pullup_failed;
1475                         eh = mtod(m, struct ether_header *);
1476                         ip = (struct ip *)(eh + 1);
1477                 } else {
1478                         eh = NULL;
1479                         ip = mtod(m, struct ip *);
1480                 }
1481                 pktlen = m->m_pkthdr.len;
1482                 args->f_id.fib = M_GETFIB(m); /* mbuf not altered */
1483         }
1484
1485         dst_ip.s_addr = 0;              /* make sure it is initialized */
1486         src_ip.s_addr = 0;              /* make sure it is initialized */
1487         src_port = dst_port = 0;
1488
1489         DYN_INFO_INIT(&dyn_info);
1490 /*
1491  * PULLUP_TO(len, p, T) makes sure that len + sizeof(T) is contiguous,
1492  * then it sets p to point at the offset "len" in the mbuf. WARNING: the
1493  * pointer might become stale after other pullups (but we never use it
1494  * this way).
1495  */
1496 #define PULLUP_TO(_len, p, T)   PULLUP_LEN(_len, p, sizeof(T))
1497 #define EHLEN   (eh != NULL ? ((char *)ip - (char *)eh) : 0)
1498 #define _PULLUP_LOCKED(_len, p, T, unlock)                      \
1499 do {                                                            \
1500         int x = (_len) + T + EHLEN;                             \
1501         if (mem) {                                              \
1502                 if (__predict_false(pktlen < x)) {              \
1503                         unlock;                                 \
1504                         goto pullup_failed;                     \
1505                 }                                               \
1506                 p = (char *)args->mem + (_len) + EHLEN;         \
1507         } else {                                                \
1508                 if (__predict_false((m)->m_len < x)) {          \
1509                         args->m = m = m_pullup(m, x);           \
1510                         if (m == NULL) {                        \
1511                                 unlock;                         \
1512                                 goto pullup_failed;             \
1513                         }                                       \
1514                 }                                               \
1515                 p = mtod(m, char *) + (_len) + EHLEN;           \
1516         }                                                       \
1517 } while (0)
1518
1519 #define PULLUP_LEN(_len, p, T)  _PULLUP_LOCKED(_len, p, T, )
1520 #define PULLUP_LEN_LOCKED(_len, p, T)   \
1521     _PULLUP_LOCKED(_len, p, T, IPFW_PF_RUNLOCK(chain)); \
1522     UPDATE_POINTERS()
1523 /*
1524  * In case pointers got stale after pullups, update them.
1525  */
1526 #define UPDATE_POINTERS()                                       \
1527 do {                                                            \
1528         if (!mem) {                                             \
1529                 if (eh != NULL) {                               \
1530                         eh = mtod(m, struct ether_header *);    \
1531                         ip = (struct ip *)(eh + 1);             \
1532                 } else                                          \
1533                         ip = mtod(m, struct ip *);              \
1534                 args->m = m;                                    \
1535         }                                                       \
1536 } while (0)
1537
1538         /* Identify IP packets and fill up variables. */
1539         if (pktlen >= sizeof(struct ip6_hdr) &&
1540             (eh == NULL || eh->ether_type == htons(ETHERTYPE_IPV6)) &&
1541             ip->ip_v == 6) {
1542                 struct ip6_hdr *ip6 = (struct ip6_hdr *)ip;
1543
1544                 is_ipv6 = 1;
1545                 args->flags |= IPFW_ARGS_IP6;
1546                 hlen = sizeof(struct ip6_hdr);
1547                 proto = ip6->ip6_nxt;
1548                 /* Search extension headers to find upper layer protocols */
1549                 while (ulp == NULL && offset == 0) {
1550                         switch (proto) {
1551                         case IPPROTO_ICMPV6:
1552                                 PULLUP_TO(hlen, ulp, struct icmp6_hdr);
1553                                 icmp6_type = ICMP6(ulp)->icmp6_type;
1554                                 break;
1555
1556                         case IPPROTO_TCP:
1557                                 PULLUP_TO(hlen, ulp, struct tcphdr);
1558                                 dst_port = TCP(ulp)->th_dport;
1559                                 src_port = TCP(ulp)->th_sport;
1560                                 /* save flags for dynamic rules */
1561                                 args->f_id._flags = TCP(ulp)->th_flags;
1562                                 break;
1563
1564                         case IPPROTO_SCTP:
1565                                 if (pktlen >= hlen + sizeof(struct sctphdr) +
1566                                     sizeof(struct sctp_chunkhdr) +
1567                                     offsetof(struct sctp_init, a_rwnd))
1568                                         PULLUP_LEN(hlen, ulp,
1569                                             sizeof(struct sctphdr) +
1570                                             sizeof(struct sctp_chunkhdr) +
1571                                             offsetof(struct sctp_init, a_rwnd));
1572                                 else if (pktlen >= hlen + sizeof(struct sctphdr))
1573                                         PULLUP_LEN(hlen, ulp, pktlen - hlen);
1574                                 else
1575                                         PULLUP_LEN(hlen, ulp,
1576                                             sizeof(struct sctphdr));
1577                                 src_port = SCTP(ulp)->src_port;
1578                                 dst_port = SCTP(ulp)->dest_port;
1579                                 break;
1580
1581                         case IPPROTO_UDP:
1582                         case IPPROTO_UDPLITE:
1583                                 PULLUP_TO(hlen, ulp, struct udphdr);
1584                                 dst_port = UDP(ulp)->uh_dport;
1585                                 src_port = UDP(ulp)->uh_sport;
1586                                 break;
1587
1588                         case IPPROTO_HOPOPTS:   /* RFC 2460 */
1589                                 PULLUP_TO(hlen, ulp, struct ip6_hbh);
1590                                 ext_hd |= EXT_HOPOPTS;
1591                                 hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3;
1592                                 proto = ((struct ip6_hbh *)ulp)->ip6h_nxt;
1593                                 ulp = NULL;
1594                                 break;
1595
1596                         case IPPROTO_ROUTING:   /* RFC 2460 */
1597                                 PULLUP_TO(hlen, ulp, struct ip6_rthdr);
1598                                 switch (((struct ip6_rthdr *)ulp)->ip6r_type) {
1599                                 case 0:
1600                                         ext_hd |= EXT_RTHDR0;
1601                                         break;
1602                                 case 2:
1603                                         ext_hd |= EXT_RTHDR2;
1604                                         break;
1605                                 default:
1606                                         if (V_fw_verbose)
1607                                                 printf("IPFW2: IPV6 - Unknown "
1608                                                     "Routing Header type(%d)\n",
1609                                                     ((struct ip6_rthdr *)
1610                                                     ulp)->ip6r_type);
1611                                         if (V_fw_deny_unknown_exthdrs)
1612                                             return (IP_FW_DENY);
1613                                         break;
1614                                 }
1615                                 ext_hd |= EXT_ROUTING;
1616                                 hlen += (((struct ip6_rthdr *)ulp)->ip6r_len + 1) << 3;
1617                                 proto = ((struct ip6_rthdr *)ulp)->ip6r_nxt;
1618                                 ulp = NULL;
1619                                 break;
1620
1621                         case IPPROTO_FRAGMENT:  /* RFC 2460 */
1622                                 PULLUP_TO(hlen, ulp, struct ip6_frag);
1623                                 ext_hd |= EXT_FRAGMENT;
1624                                 hlen += sizeof (struct ip6_frag);
1625                                 proto = ((struct ip6_frag *)ulp)->ip6f_nxt;
1626                                 offset = ((struct ip6_frag *)ulp)->ip6f_offlg &
1627                                         IP6F_OFF_MASK;
1628                                 ip6f_mf = ((struct ip6_frag *)ulp)->ip6f_offlg &
1629                                         IP6F_MORE_FRAG;
1630                                 if (V_fw_permit_single_frag6 == 0 &&
1631                                     offset == 0 && ip6f_mf == 0) {
1632                                         if (V_fw_verbose)
1633                                                 printf("IPFW2: IPV6 - Invalid "
1634                                                     "Fragment Header\n");
1635                                         if (V_fw_deny_unknown_exthdrs)
1636                                             return (IP_FW_DENY);
1637                                         break;
1638                                 }
1639                                 args->f_id.extra =
1640                                     ntohl(((struct ip6_frag *)ulp)->ip6f_ident);
1641                                 ulp = NULL;
1642                                 break;
1643
1644                         case IPPROTO_DSTOPTS:   /* RFC 2460 */
1645                                 PULLUP_TO(hlen, ulp, struct ip6_hbh);
1646                                 ext_hd |= EXT_DSTOPTS;
1647                                 hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3;
1648                                 proto = ((struct ip6_hbh *)ulp)->ip6h_nxt;
1649                                 ulp = NULL;
1650                                 break;
1651
1652                         case IPPROTO_AH:        /* RFC 2402 */
1653                                 PULLUP_TO(hlen, ulp, struct ip6_ext);
1654                                 ext_hd |= EXT_AH;
1655                                 hlen += (((struct ip6_ext *)ulp)->ip6e_len + 2) << 2;
1656                                 proto = ((struct ip6_ext *)ulp)->ip6e_nxt;
1657                                 ulp = NULL;
1658                                 break;
1659
1660                         case IPPROTO_ESP:       /* RFC 2406 */
1661                                 PULLUP_TO(hlen, ulp, uint32_t); /* SPI, Seq# */
1662                                 /* Anything past Seq# is variable length and
1663                                  * data past this ext. header is encrypted. */
1664                                 ext_hd |= EXT_ESP;
1665                                 break;
1666
1667                         case IPPROTO_NONE:      /* RFC 2460 */
1668                                 /*
1669                                  * Packet ends here, and IPv6 header has
1670                                  * already been pulled up. If ip6e_len!=0
1671                                  * then octets must be ignored.
1672                                  */
1673                                 ulp = ip; /* non-NULL to get out of loop. */
1674                                 break;
1675
1676                         case IPPROTO_OSPFIGP:
1677                                 /* XXX OSPF header check? */
1678                                 PULLUP_TO(hlen, ulp, struct ip6_ext);
1679                                 break;
1680
1681                         case IPPROTO_PIM:
1682                                 /* XXX PIM header check? */
1683                                 PULLUP_TO(hlen, ulp, struct pim);
1684                                 break;
1685
1686                         case IPPROTO_GRE:       /* RFC 1701 */
1687                                 /* XXX GRE header check? */
1688                                 PULLUP_TO(hlen, ulp, struct grehdr);
1689                                 break;
1690
1691                         case IPPROTO_CARP:
1692                                 PULLUP_TO(hlen, ulp, offsetof(
1693                                     struct carp_header, carp_counter));
1694                                 if (CARP_ADVERTISEMENT !=
1695                                     ((struct carp_header *)ulp)->carp_type)
1696                                         return (IP_FW_DENY);
1697                                 break;
1698
1699                         case IPPROTO_IPV6:      /* RFC 2893 */
1700                                 PULLUP_TO(hlen, ulp, struct ip6_hdr);
1701                                 break;
1702
1703                         case IPPROTO_IPV4:      /* RFC 2893 */
1704                                 PULLUP_TO(hlen, ulp, struct ip);
1705                                 break;
1706
1707                         default:
1708                                 if (V_fw_verbose)
1709                                         printf("IPFW2: IPV6 - Unknown "
1710                                             "Extension Header(%d), ext_hd=%x\n",
1711                                              proto, ext_hd);
1712                                 if (V_fw_deny_unknown_exthdrs)
1713                                     return (IP_FW_DENY);
1714                                 PULLUP_TO(hlen, ulp, struct ip6_ext);
1715                                 break;
1716                         } /*switch */
1717                 }
1718                 UPDATE_POINTERS();
1719                 ip6 = (struct ip6_hdr *)ip;
1720                 args->f_id.addr_type = 6;
1721                 args->f_id.src_ip6 = ip6->ip6_src;
1722                 args->f_id.dst_ip6 = ip6->ip6_dst;
1723                 args->f_id.flow_id6 = ntohl(ip6->ip6_flow);
1724                 iplen = ntohs(ip6->ip6_plen) + sizeof(*ip6);
1725         } else if (pktlen >= sizeof(struct ip) &&
1726             (eh == NULL || eh->ether_type == htons(ETHERTYPE_IP)) &&
1727             ip->ip_v == 4) {
1728                 is_ipv4 = 1;
1729                 args->flags |= IPFW_ARGS_IP4;
1730                 hlen = ip->ip_hl << 2;
1731                 /*
1732                  * Collect parameters into local variables for faster
1733                  * matching.
1734                  */
1735                 proto = ip->ip_p;
1736                 src_ip = ip->ip_src;
1737                 dst_ip = ip->ip_dst;
1738                 offset = ntohs(ip->ip_off) & IP_OFFMASK;
1739                 iplen = ntohs(ip->ip_len);
1740
1741                 if (offset == 0) {
1742                         switch (proto) {
1743                         case IPPROTO_TCP:
1744                                 PULLUP_TO(hlen, ulp, struct tcphdr);
1745                                 dst_port = TCP(ulp)->th_dport;
1746                                 src_port = TCP(ulp)->th_sport;
1747                                 /* save flags for dynamic rules */
1748                                 args->f_id._flags = TCP(ulp)->th_flags;
1749                                 break;
1750
1751                         case IPPROTO_SCTP:
1752                                 if (pktlen >= hlen + sizeof(struct sctphdr) +
1753                                     sizeof(struct sctp_chunkhdr) +
1754                                     offsetof(struct sctp_init, a_rwnd))
1755                                         PULLUP_LEN(hlen, ulp,
1756                                             sizeof(struct sctphdr) +
1757                                             sizeof(struct sctp_chunkhdr) +
1758                                             offsetof(struct sctp_init, a_rwnd));
1759                                 else if (pktlen >= hlen + sizeof(struct sctphdr))
1760                                         PULLUP_LEN(hlen, ulp, pktlen - hlen);
1761                                 else
1762                                         PULLUP_LEN(hlen, ulp,
1763                                             sizeof(struct sctphdr));
1764                                 src_port = SCTP(ulp)->src_port;
1765                                 dst_port = SCTP(ulp)->dest_port;
1766                                 break;
1767
1768                         case IPPROTO_UDP:
1769                         case IPPROTO_UDPLITE:
1770                                 PULLUP_TO(hlen, ulp, struct udphdr);
1771                                 dst_port = UDP(ulp)->uh_dport;
1772                                 src_port = UDP(ulp)->uh_sport;
1773                                 break;
1774
1775                         case IPPROTO_ICMP:
1776                                 PULLUP_TO(hlen, ulp, struct icmphdr);
1777                                 //args->f_id.flags = ICMP(ulp)->icmp_type;
1778                                 break;
1779
1780                         default:
1781                                 break;
1782                         }
1783                 } else {
1784                         if (offset == 1 && proto == IPPROTO_TCP) {
1785                                 /* RFC 3128 */
1786                                 goto pullup_failed;
1787                         }
1788                 }
1789
1790                 UPDATE_POINTERS();
1791                 args->f_id.addr_type = 4;
1792                 args->f_id.src_ip = ntohl(src_ip.s_addr);
1793                 args->f_id.dst_ip = ntohl(dst_ip.s_addr);
1794         } else {
1795                 proto = 0;
1796                 dst_ip.s_addr = src_ip.s_addr = 0;
1797
1798                 args->f_id.addr_type = 1; /* XXX */
1799         }
1800 #undef PULLUP_TO
1801         pktlen = iplen < pktlen ? iplen: pktlen;
1802
1803         /* Properly initialize the rest of f_id */
1804         args->f_id.proto = proto;
1805         args->f_id.src_port = src_port = ntohs(src_port);
1806         args->f_id.dst_port = dst_port = ntohs(dst_port);
1807
1808         IPFW_PF_RLOCK(chain);
1809         if (! V_ipfw_vnet_ready) { /* shutting down, leave NOW. */
1810                 IPFW_PF_RUNLOCK(chain);
1811                 return (IP_FW_PASS);    /* accept */
1812         }
1813         if (args->flags & IPFW_ARGS_REF) {
1814                 /*
1815                  * Packet has already been tagged as a result of a previous
1816                  * match on rule args->rule aka args->rule_id (PIPE, QUEUE,
1817                  * REASS, NETGRAPH, DIVERT/TEE...)
1818                  * Validate the slot and continue from the next one
1819                  * if still present, otherwise do a lookup.
1820                  */
1821                 f_pos = (args->rule.chain_id == chain->id) ?
1822                     args->rule.slot :
1823                     ipfw_find_rule(chain, args->rule.rulenum,
1824                         args->rule.rule_id);
1825         } else {
1826                 f_pos = 0;
1827         }
1828
1829         if (args->flags & IPFW_ARGS_IN) {
1830                 iif = args->ifp;
1831                 oif = NULL;
1832         } else {
1833                 MPASS(args->flags & IPFW_ARGS_OUT);
1834                 iif = mem ? NULL : m_rcvif(m);
1835                 oif = args->ifp;
1836         }
1837
1838         /*
1839          * Now scan the rules, and parse microinstructions for each rule.
1840          * We have two nested loops and an inner switch. Sometimes we
1841          * need to break out of one or both loops, or re-enter one of
1842          * the loops with updated variables. Loop variables are:
1843          *
1844          *      f_pos (outer loop) points to the current rule.
1845          *              On output it points to the matching rule.
1846          *      done (outer loop) is used as a flag to break the loop.
1847          *      l (inner loop)  residual length of current rule.
1848          *              cmd points to the current microinstruction.
1849          *
1850          * We break the inner loop by setting l=0 and possibly
1851          * cmdlen=0 if we don't want to advance cmd.
1852          * We break the outer loop by setting done=1
1853          * We can restart the inner loop by setting l>0 and f_pos, f, cmd
1854          * as needed.
1855          */
1856         for (; f_pos < chain->n_rules; f_pos++) {
1857                 ipfw_insn *cmd;
1858                 uint32_t tablearg = 0;
1859                 int l, cmdlen, skip_or; /* skip rest of OR block */
1860                 struct ip_fw *f;
1861
1862                 f = chain->map[f_pos];
1863                 if (V_set_disable & (1 << f->set) )
1864                         continue;
1865
1866                 skip_or = 0;
1867                 for (l = f->cmd_len, cmd = f->cmd ; l > 0 ;
1868                     l -= cmdlen, cmd += cmdlen) {
1869                         int match;
1870
1871                         /*
1872                          * check_body is a jump target used when we find a
1873                          * CHECK_STATE, and need to jump to the body of
1874                          * the target rule.
1875                          */
1876
1877 /* check_body: */
1878                         cmdlen = F_LEN(cmd);
1879                         /*
1880                          * An OR block (insn_1 || .. || insn_n) has the
1881                          * F_OR bit set in all but the last instruction.
1882                          * The first match will set "skip_or", and cause
1883                          * the following instructions to be skipped until
1884                          * past the one with the F_OR bit clear.
1885                          */
1886                         if (skip_or) {          /* skip this instruction */
1887                                 if ((cmd->len & F_OR) == 0)
1888                                         skip_or = 0;    /* next one is good */
1889                                 continue;
1890                         }
1891                         match = 0; /* set to 1 if we succeed */
1892
1893                         switch (cmd->opcode) {
1894                         /*
1895                          * The first set of opcodes compares the packet's
1896                          * fields with some pattern, setting 'match' if a
1897                          * match is found. At the end of the loop there is
1898                          * logic to deal with F_NOT and F_OR flags associated
1899                          * with the opcode.
1900                          */
1901                         case O_NOP:
1902                                 match = 1;
1903                                 break;
1904
1905                         case O_FORWARD_MAC:
1906                                 printf("ipfw: opcode %d unimplemented\n",
1907                                     cmd->opcode);
1908                                 break;
1909
1910                         case O_GID:
1911                         case O_UID:
1912                         case O_JAIL:
1913                                 /*
1914                                  * We only check offset == 0 && proto != 0,
1915                                  * as this ensures that we have a
1916                                  * packet with the ports info.
1917                                  */
1918                                 if (offset != 0)
1919                                         break;
1920                                 if (proto == IPPROTO_TCP ||
1921                                     proto == IPPROTO_UDP ||
1922                                     proto == IPPROTO_UDPLITE)
1923                                         match = check_uidgid(
1924                                                     (ipfw_insn_u32 *)cmd,
1925                                                     args, &ucred_lookup,
1926 #ifdef __FreeBSD__
1927                                                     &ucred_cache);
1928 #else
1929                                                     (void *)&ucred_cache);
1930 #endif
1931                                 break;
1932
1933                         case O_RECV:
1934                                 match = iface_match(iif, (ipfw_insn_if *)cmd,
1935                                     chain, &tablearg);
1936                                 break;
1937
1938                         case O_XMIT:
1939                                 match = iface_match(oif, (ipfw_insn_if *)cmd,
1940                                     chain, &tablearg);
1941                                 break;
1942
1943                         case O_VIA:
1944                                 match = iface_match(args->ifp,
1945                                     (ipfw_insn_if *)cmd, chain, &tablearg);
1946                                 break;
1947
1948                         case O_MACADDR2:
1949                                 if (args->flags & IPFW_ARGS_ETHER) {
1950                                         u_int32_t *want = (u_int32_t *)
1951                                                 ((ipfw_insn_mac *)cmd)->addr;
1952                                         u_int32_t *mask = (u_int32_t *)
1953                                                 ((ipfw_insn_mac *)cmd)->mask;
1954                                         u_int32_t *hdr = (u_int32_t *)eh;
1955
1956                                         match =
1957                                             ( want[0] == (hdr[0] & mask[0]) &&
1958                                               want[1] == (hdr[1] & mask[1]) &&
1959                                               want[2] == (hdr[2] & mask[2]) );
1960                                 }
1961                                 break;
1962
1963                         case O_MAC_TYPE:
1964                                 if (args->flags & IPFW_ARGS_ETHER) {
1965                                         u_int16_t *p =
1966                                             ((ipfw_insn_u16 *)cmd)->ports;
1967                                         int i;
1968
1969                                         for (i = cmdlen - 1; !match && i>0;
1970                                             i--, p += 2)
1971                                                 match =
1972                                                     (ntohs(eh->ether_type) >=
1973                                                     p[0] &&
1974                                                     ntohs(eh->ether_type) <=
1975                                                     p[1]);
1976                                 }
1977                                 break;
1978
1979                         case O_FRAG:
1980                                 if (is_ipv4) {
1981                                         /*
1982                                          * Since flags_match() works with
1983                                          * uint8_t we pack ip_off into 8 bits.
1984                                          * For this match offset is a boolean.
1985                                          */
1986                                         match = flags_match(cmd,
1987                                             ((ntohs(ip->ip_off) & ~IP_OFFMASK)
1988                                             >> 8) | (offset != 0));
1989                                 } else {
1990                                         /*
1991                                          * Compatiblity: historically bare
1992                                          * "frag" would match IPv6 fragments.
1993                                          */
1994                                         match = (cmd->arg1 == 0x1 &&
1995                                             (offset != 0));
1996                                 }
1997                                 break;
1998
1999                         case O_IN:      /* "out" is "not in" */
2000                                 match = (oif == NULL);
2001                                 break;
2002
2003                         case O_LAYER2:
2004                                 match = (args->flags & IPFW_ARGS_ETHER);
2005                                 break;
2006
2007                         case O_DIVERTED:
2008                                 if ((args->flags & IPFW_ARGS_REF) == 0)
2009                                         break;
2010                                 /*
2011                                  * For diverted packets, args->rule.info
2012                                  * contains the divert port (in host format)
2013                                  * reason and direction.
2014                                  */
2015                                 match = ((args->rule.info & IPFW_IS_MASK) ==
2016                                     IPFW_IS_DIVERT) && (
2017                                     ((args->rule.info & IPFW_INFO_IN) ?
2018                                         1: 2) & cmd->arg1);
2019                                 break;
2020
2021                         case O_PROTO:
2022                                 /*
2023                                  * We do not allow an arg of 0 so the
2024                                  * check of "proto" only suffices.
2025                                  */
2026                                 match = (proto == cmd->arg1);
2027                                 break;
2028
2029                         case O_IP_SRC:
2030                                 match = is_ipv4 &&
2031                                     (((ipfw_insn_ip *)cmd)->addr.s_addr ==
2032                                     src_ip.s_addr);
2033                                 break;
2034
2035                         case O_IP_DST_LOOKUP:
2036                         {
2037                                 void *pkey;
2038                                 uint32_t vidx, key;
2039                                 uint16_t keylen;
2040
2041                                 if (cmdlen > F_INSN_SIZE(ipfw_insn_u32)) {
2042                                         /* Determine lookup key type */
2043                                         vidx = ((ipfw_insn_u32 *)cmd)->d[1];
2044                                         if (vidx != 4 /* uid */ &&
2045                                             vidx != 5 /* jail */ &&
2046                                             is_ipv6 == 0 && is_ipv4 == 0)
2047                                                 break;
2048                                         /* Determine key length */
2049                                         if (vidx == 0 /* dst-ip */ ||
2050                                             vidx == 1 /* src-ip */)
2051                                                 keylen = is_ipv6 ?
2052                                                     sizeof(struct in6_addr):
2053                                                     sizeof(in_addr_t);
2054                                         else {
2055                                                 keylen = sizeof(key);
2056                                                 pkey = &key;
2057                                         }
2058                                         if (vidx == 0 /* dst-ip */)
2059                                                 pkey = is_ipv4 ? (void *)&dst_ip:
2060                                                     (void *)&args->f_id.dst_ip6;
2061                                         else if (vidx == 1 /* src-ip */)
2062                                                 pkey = is_ipv4 ? (void *)&src_ip:
2063                                                     (void *)&args->f_id.src_ip6;
2064                                         else if (vidx == 6 /* dscp */) {
2065                                                 if (is_ipv4)
2066                                                         key = ip->ip_tos >> 2;
2067                                                 else {
2068                                                         key = args->f_id.flow_id6;
2069                                                         key = (key & 0x0f) << 2 |
2070                                                             (key & 0xf000) >> 14;
2071                                                 }
2072                                                 key &= 0x3f;
2073                                         } else if (vidx == 2 /* dst-port */ ||
2074                                             vidx == 3 /* src-port */) {
2075                                                 /* Skip fragments */
2076                                                 if (offset != 0)
2077                                                         break;
2078                                                 /* Skip proto without ports */
2079                                                 if (proto != IPPROTO_TCP &&
2080                                                     proto != IPPROTO_UDP &&
2081                                                     proto != IPPROTO_UDPLITE &&
2082                                                     proto != IPPROTO_SCTP)
2083                                                         break;
2084                                                 if (vidx == 2 /* dst-port */)
2085                                                         key = dst_port;
2086                                                 else
2087                                                         key = src_port;
2088                                         }
2089 #ifndef USERSPACE
2090                                         else if (vidx == 4 /* uid */ ||
2091                                             vidx == 5 /* jail */) {
2092                                                 check_uidgid(
2093                                                     (ipfw_insn_u32 *)cmd,
2094                                                     args, &ucred_lookup,
2095 #ifdef __FreeBSD__
2096                                                     &ucred_cache);
2097                                                 if (vidx == 4 /* uid */)
2098                                                         key = ucred_cache->cr_uid;
2099                                                 else if (vidx == 5 /* jail */)
2100                                                         key = ucred_cache->cr_prison->pr_id;
2101 #else /* !__FreeBSD__ */
2102                                                     (void *)&ucred_cache);
2103                                                 if (vidx == 4 /* uid */)
2104                                                         key = ucred_cache.uid;
2105                                                 else if (vidx == 5 /* jail */)
2106                                                         key = ucred_cache.xid;
2107 #endif /* !__FreeBSD__ */
2108                                         }
2109 #endif /* !USERSPACE */
2110                                         else
2111                                                 break;
2112                                         match = ipfw_lookup_table(chain,
2113                                             cmd->arg1, keylen, pkey, &vidx);
2114                                         if (!match)
2115                                                 break;
2116                                         tablearg = vidx;
2117                                         break;
2118                                 }
2119                                 /* cmdlen =< F_INSN_SIZE(ipfw_insn_u32) */
2120                                 /* FALLTHROUGH */
2121                         }
2122                         case O_IP_SRC_LOOKUP:
2123                         {
2124                                 void *pkey;
2125                                 uint32_t vidx;
2126                                 uint16_t keylen;
2127
2128                                 if (is_ipv4) {
2129                                         keylen = sizeof(in_addr_t);
2130                                         if (cmd->opcode == O_IP_DST_LOOKUP)
2131                                                 pkey = &dst_ip;
2132                                         else
2133                                                 pkey = &src_ip;
2134                                 } else if (is_ipv6) {
2135                                         keylen = sizeof(struct in6_addr);
2136                                         if (cmd->opcode == O_IP_DST_LOOKUP)
2137                                                 pkey = &args->f_id.dst_ip6;
2138                                         else
2139                                                 pkey = &args->f_id.src_ip6;
2140                                 } else
2141                                         break;
2142                                 match = ipfw_lookup_table(chain, cmd->arg1,
2143                                     keylen, pkey, &vidx);
2144                                 if (!match)
2145                                         break;
2146                                 if (cmdlen == F_INSN_SIZE(ipfw_insn_u32)) {
2147                                         match = ((ipfw_insn_u32 *)cmd)->d[0] ==
2148                                             TARG_VAL(chain, vidx, tag);
2149                                         if (!match)
2150                                                 break;
2151                                 }
2152                                 tablearg = vidx;
2153                                 break;
2154                         }
2155
2156                         case O_IP_FLOW_LOOKUP:
2157                                 {
2158                                         uint32_t v = 0;
2159                                         match = ipfw_lookup_table(chain,
2160                                             cmd->arg1, 0, &args->f_id, &v);
2161                                         if (!match)
2162                                                 break;
2163                                         if (cmdlen == F_INSN_SIZE(ipfw_insn_u32))
2164                                                 match = ((ipfw_insn_u32 *)cmd)->d[0] ==
2165                                                     TARG_VAL(chain, v, tag);
2166                                         if (match)
2167                                                 tablearg = v;
2168                                 }
2169                                 break;
2170                         case O_IP_SRC_MASK:
2171                         case O_IP_DST_MASK:
2172                                 if (is_ipv4) {
2173                                     uint32_t a =
2174                                         (cmd->opcode == O_IP_DST_MASK) ?
2175                                             dst_ip.s_addr : src_ip.s_addr;
2176                                     uint32_t *p = ((ipfw_insn_u32 *)cmd)->d;
2177                                     int i = cmdlen-1;
2178
2179                                     for (; !match && i>0; i-= 2, p+= 2)
2180                                         match = (p[0] == (a & p[1]));
2181                                 }
2182                                 break;
2183
2184                         case O_IP_SRC_ME:
2185                                 if (is_ipv4) {
2186                                         match = in_localip(src_ip);
2187                                         break;
2188                                 }
2189 #ifdef INET6
2190                                 /* FALLTHROUGH */
2191                         case O_IP6_SRC_ME:
2192                                 match = is_ipv6 &&
2193                                     ipfw_localip6(&args->f_id.src_ip6);
2194 #endif
2195                                 break;
2196
2197                         case O_IP_DST_SET:
2198                         case O_IP_SRC_SET:
2199                                 if (is_ipv4) {
2200                                         u_int32_t *d = (u_int32_t *)(cmd+1);
2201                                         u_int32_t addr =
2202                                             cmd->opcode == O_IP_DST_SET ?
2203                                                 args->f_id.dst_ip :
2204                                                 args->f_id.src_ip;
2205
2206                                             if (addr < d[0])
2207                                                     break;
2208                                             addr -= d[0]; /* subtract base */
2209                                             match = (addr < cmd->arg1) &&
2210                                                 ( d[ 1 + (addr>>5)] &
2211                                                   (1<<(addr & 0x1f)) );
2212                                 }
2213                                 break;
2214
2215                         case O_IP_DST:
2216                                 match = is_ipv4 &&
2217                                     (((ipfw_insn_ip *)cmd)->addr.s_addr ==
2218                                     dst_ip.s_addr);
2219                                 break;
2220
2221                         case O_IP_DST_ME:
2222                                 if (is_ipv4) {
2223                                         match = in_localip(dst_ip);
2224                                         break;
2225                                 }
2226 #ifdef INET6
2227                                 /* FALLTHROUGH */
2228                         case O_IP6_DST_ME:
2229                                 match = is_ipv6 &&
2230                                     ipfw_localip6(&args->f_id.dst_ip6);
2231 #endif
2232                                 break;
2233
2234                         case O_IP_SRCPORT:
2235                         case O_IP_DSTPORT:
2236                                 /*
2237                                  * offset == 0 && proto != 0 is enough
2238                                  * to guarantee that we have a
2239                                  * packet with port info.
2240                                  */
2241                                 if ((proto == IPPROTO_UDP ||
2242                                     proto == IPPROTO_UDPLITE ||
2243                                     proto == IPPROTO_TCP ||
2244                                     proto == IPPROTO_SCTP) && offset == 0) {
2245                                         u_int16_t x =
2246                                             (cmd->opcode == O_IP_SRCPORT) ?
2247                                                 src_port : dst_port ;
2248                                         u_int16_t *p =
2249                                             ((ipfw_insn_u16 *)cmd)->ports;
2250                                         int i;
2251
2252                                         for (i = cmdlen - 1; !match && i>0;
2253                                             i--, p += 2)
2254                                                 match = (x>=p[0] && x<=p[1]);
2255                                 }
2256                                 break;
2257
2258                         case O_ICMPTYPE:
2259                                 match = (offset == 0 && proto==IPPROTO_ICMP &&
2260                                     icmptype_match(ICMP(ulp), (ipfw_insn_u32 *)cmd) );
2261                                 break;
2262
2263 #ifdef INET6
2264                         case O_ICMP6TYPE:
2265                                 match = is_ipv6 && offset == 0 &&
2266                                     proto==IPPROTO_ICMPV6 &&
2267                                     icmp6type_match(
2268                                         ICMP6(ulp)->icmp6_type,
2269                                         (ipfw_insn_u32 *)cmd);
2270                                 break;
2271 #endif /* INET6 */
2272
2273                         case O_IPOPT:
2274                                 match = (is_ipv4 &&
2275                                     ipopts_match(ip, cmd) );
2276                                 break;
2277
2278                         case O_IPVER:
2279                                 match = ((is_ipv4 || is_ipv6) &&
2280                                     cmd->arg1 == ip->ip_v);
2281                                 break;
2282
2283                         case O_IPID:
2284                         case O_IPTTL:
2285                                 if (!is_ipv4)
2286                                         break;
2287                         case O_IPLEN:
2288                                 {       /* only for IP packets */
2289                                     uint16_t x;
2290                                     uint16_t *p;
2291                                     int i;
2292
2293                                     if (cmd->opcode == O_IPLEN)
2294                                         x = iplen;
2295                                     else if (cmd->opcode == O_IPTTL)
2296                                         x = ip->ip_ttl;
2297                                     else /* must be IPID */
2298                                         x = ntohs(ip->ip_id);
2299                                     if (cmdlen == 1) {
2300                                         match = (cmd->arg1 == x);
2301                                         break;
2302                                     }
2303                                     /* otherwise we have ranges */
2304                                     p = ((ipfw_insn_u16 *)cmd)->ports;
2305                                     i = cmdlen - 1;
2306                                     for (; !match && i>0; i--, p += 2)
2307                                         match = (x >= p[0] && x <= p[1]);
2308                                 }
2309                                 break;
2310
2311                         case O_IPPRECEDENCE:
2312                                 match = (is_ipv4 &&
2313                                     (cmd->arg1 == (ip->ip_tos & 0xe0)) );
2314                                 break;
2315
2316                         case O_IPTOS:
2317                                 match = (is_ipv4 &&
2318                                     flags_match(cmd, ip->ip_tos));
2319                                 break;
2320
2321                         case O_DSCP:
2322                             {
2323                                 uint32_t *p;
2324                                 uint16_t x;
2325
2326                                 p = ((ipfw_insn_u32 *)cmd)->d;
2327
2328                                 if (is_ipv4)
2329                                         x = ip->ip_tos >> 2;
2330                                 else if (is_ipv6) {
2331                                         uint8_t *v;
2332                                         v = &((struct ip6_hdr *)ip)->ip6_vfc;
2333                                         x = (*v & 0x0F) << 2;
2334                                         v++;
2335                                         x |= *v >> 6;
2336                                 } else
2337                                         break;
2338
2339                                 /* DSCP bitmask is stored as low_u32 high_u32 */
2340                                 if (x >= 32)
2341                                         match = *(p + 1) & (1 << (x - 32));
2342                                 else
2343                                         match = *p & (1 << x);
2344                             }
2345                                 break;
2346
2347                         case O_TCPDATALEN:
2348                                 if (proto == IPPROTO_TCP && offset == 0) {
2349                                     struct tcphdr *tcp;
2350                                     uint16_t x;
2351                                     uint16_t *p;
2352                                     int i;
2353 #ifdef INET6
2354                                     if (is_ipv6) {
2355                                             struct ip6_hdr *ip6;
2356
2357                                             ip6 = (struct ip6_hdr *)ip;
2358                                             if (ip6->ip6_plen == 0) {
2359                                                     /*
2360                                                      * Jumbo payload is not
2361                                                      * supported by this
2362                                                      * opcode.
2363                                                      */
2364                                                     break;
2365                                             }
2366                                             x = iplen - hlen;
2367                                     } else
2368 #endif /* INET6 */
2369                                             x = iplen - (ip->ip_hl << 2);
2370                                     tcp = TCP(ulp);
2371                                     x -= tcp->th_off << 2;
2372                                     if (cmdlen == 1) {
2373                                         match = (cmd->arg1 == x);
2374                                         break;
2375                                     }
2376                                     /* otherwise we have ranges */
2377                                     p = ((ipfw_insn_u16 *)cmd)->ports;
2378                                     i = cmdlen - 1;
2379                                     for (; !match && i>0; i--, p += 2)
2380                                         match = (x >= p[0] && x <= p[1]);
2381                                 }
2382                                 break;
2383
2384                         case O_TCPFLAGS:
2385                                 match = (proto == IPPROTO_TCP && offset == 0 &&
2386                                     flags_match(cmd, TCP(ulp)->th_flags));
2387                                 break;
2388
2389                         case O_TCPOPTS:
2390                                 if (proto == IPPROTO_TCP && offset == 0 && ulp){
2391                                         PULLUP_LEN_LOCKED(hlen, ulp,
2392                                             (TCP(ulp)->th_off << 2));
2393                                         match = tcpopts_match(TCP(ulp), cmd);
2394                                 }
2395                                 break;
2396
2397                         case O_TCPSEQ:
2398                                 match = (proto == IPPROTO_TCP && offset == 0 &&
2399                                     ((ipfw_insn_u32 *)cmd)->d[0] ==
2400                                         TCP(ulp)->th_seq);
2401                                 break;
2402
2403                         case O_TCPACK:
2404                                 match = (proto == IPPROTO_TCP && offset == 0 &&
2405                                     ((ipfw_insn_u32 *)cmd)->d[0] ==
2406                                         TCP(ulp)->th_ack);
2407                                 break;
2408
2409                         case O_TCPMSS:
2410                                 if (proto == IPPROTO_TCP &&
2411                                     (args->f_id._flags & TH_SYN) != 0 &&
2412                                     ulp != NULL) {
2413                                         uint16_t mss, *p;
2414                                         int i;
2415
2416                                         PULLUP_LEN_LOCKED(hlen, ulp,
2417                                             (TCP(ulp)->th_off << 2));
2418                                         if ((tcpopts_parse(TCP(ulp), &mss) &
2419                                             IP_FW_TCPOPT_MSS) == 0)
2420                                                 break;
2421                                         if (cmdlen == 1) {
2422                                                 match = (cmd->arg1 == mss);
2423                                                 break;
2424                                         }
2425                                         /* Otherwise we have ranges. */
2426                                         p = ((ipfw_insn_u16 *)cmd)->ports;
2427                                         i = cmdlen - 1;
2428                                         for (; !match && i > 0; i--, p += 2)
2429                                                 match = (mss >= p[0] &&
2430                                                     mss <= p[1]);
2431                                 }
2432                                 break;
2433
2434                         case O_TCPWIN:
2435                                 if (proto == IPPROTO_TCP && offset == 0) {
2436                                     uint16_t x;
2437                                     uint16_t *p;
2438                                     int i;
2439
2440                                     x = ntohs(TCP(ulp)->th_win);
2441                                     if (cmdlen == 1) {
2442                                         match = (cmd->arg1 == x);
2443                                         break;
2444                                     }
2445                                     /* Otherwise we have ranges. */
2446                                     p = ((ipfw_insn_u16 *)cmd)->ports;
2447                                     i = cmdlen - 1;
2448                                     for (; !match && i > 0; i--, p += 2)
2449                                         match = (x >= p[0] && x <= p[1]);
2450                                 }
2451                                 break;
2452
2453                         case O_ESTAB:
2454                                 /* reject packets which have SYN only */
2455                                 /* XXX should i also check for TH_ACK ? */
2456                                 match = (proto == IPPROTO_TCP && offset == 0 &&
2457                                     (TCP(ulp)->th_flags &
2458                                      (TH_RST | TH_ACK | TH_SYN)) != TH_SYN);
2459                                 break;
2460
2461                         case O_ALTQ: {
2462                                 struct pf_mtag *at;
2463                                 struct m_tag *mtag;
2464                                 ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
2465
2466                                 /*
2467                                  * ALTQ uses mbuf tags from another
2468                                  * packet filtering system - pf(4).
2469                                  * We allocate a tag in its format
2470                                  * and fill it in, pretending to be pf(4).
2471                                  */
2472                                 match = 1;
2473                                 at = pf_find_mtag(m);
2474                                 if (at != NULL && at->qid != 0)
2475                                         break;
2476                                 mtag = m_tag_get(PACKET_TAG_PF,
2477                                     sizeof(struct pf_mtag), M_NOWAIT | M_ZERO);
2478                                 if (mtag == NULL) {
2479                                         /*
2480                                          * Let the packet fall back to the
2481                                          * default ALTQ.
2482                                          */
2483                                         break;
2484                                 }
2485                                 m_tag_prepend(m, mtag);
2486                                 at = (struct pf_mtag *)(mtag + 1);
2487                                 at->qid = altq->qid;
2488                                 at->hdr = ip;
2489                                 break;
2490                         }
2491
2492                         case O_LOG:
2493                                 ipfw_log(chain, f, hlen, args,
2494                                     offset | ip6f_mf, tablearg, ip);
2495                                 match = 1;
2496                                 break;
2497
2498                         case O_PROB:
2499                                 match = (random()<((ipfw_insn_u32 *)cmd)->d[0]);
2500                                 break;
2501
2502                         case O_VERREVPATH:
2503                                 /* Outgoing packets automatically pass/match */
2504                                 match = (args->flags & IPFW_ARGS_OUT ||
2505                                     (
2506 #ifdef INET6
2507                                     is_ipv6 ?
2508                                         verify_path6(&(args->f_id.src_ip6),
2509                                             iif, args->f_id.fib) :
2510 #endif
2511                                     verify_path(src_ip, iif, args->f_id.fib)));
2512                                 break;
2513
2514                         case O_VERSRCREACH:
2515                                 /* Outgoing packets automatically pass/match */
2516                                 match = (hlen > 0 && ((oif != NULL) || (
2517 #ifdef INET6
2518                                     is_ipv6 ?
2519                                         verify_path6(&(args->f_id.src_ip6),
2520                                             NULL, args->f_id.fib) :
2521 #endif
2522                                     verify_path(src_ip, NULL, args->f_id.fib))));
2523                                 break;
2524
2525                         case O_ANTISPOOF:
2526                                 /* Outgoing packets automatically pass/match */
2527                                 if (oif == NULL && hlen > 0 &&
2528                                     (  (is_ipv4 && in_localaddr(src_ip))
2529 #ifdef INET6
2530                                     || (is_ipv6 &&
2531                                         in6_localaddr(&(args->f_id.src_ip6)))
2532 #endif
2533                                     ))
2534                                         match =
2535 #ifdef INET6
2536                                             is_ipv6 ? verify_path6(
2537                                                 &(args->f_id.src_ip6), iif,
2538                                                 args->f_id.fib) :
2539 #endif
2540                                             verify_path(src_ip, iif,
2541                                                 args->f_id.fib);
2542                                 else
2543                                         match = 1;
2544                                 break;
2545
2546                         case O_IPSEC:
2547                                 match = (m_tag_find(m,
2548                                     PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL);
2549                                 /* otherwise no match */
2550                                 break;
2551
2552 #ifdef INET6
2553                         case O_IP6_SRC:
2554                                 match = is_ipv6 &&
2555                                     IN6_ARE_ADDR_EQUAL(&args->f_id.src_ip6,
2556                                     &((ipfw_insn_ip6 *)cmd)->addr6);
2557                                 break;
2558
2559                         case O_IP6_DST:
2560                                 match = is_ipv6 &&
2561                                 IN6_ARE_ADDR_EQUAL(&args->f_id.dst_ip6,
2562                                     &((ipfw_insn_ip6 *)cmd)->addr6);
2563                                 break;
2564                         case O_IP6_SRC_MASK:
2565                         case O_IP6_DST_MASK:
2566                                 if (is_ipv6) {
2567                                         int i = cmdlen - 1;
2568                                         struct in6_addr p;
2569                                         struct in6_addr *d =
2570                                             &((ipfw_insn_ip6 *)cmd)->addr6;
2571
2572                                         for (; !match && i > 0; d += 2,
2573                                             i -= F_INSN_SIZE(struct in6_addr)
2574                                             * 2) {
2575                                                 p = (cmd->opcode ==
2576                                                     O_IP6_SRC_MASK) ?
2577                                                     args->f_id.src_ip6:
2578                                                     args->f_id.dst_ip6;
2579                                                 APPLY_MASK(&p, &d[1]);
2580                                                 match =
2581                                                     IN6_ARE_ADDR_EQUAL(&d[0],
2582                                                     &p);
2583                                         }
2584                                 }
2585                                 break;
2586
2587                         case O_FLOW6ID:
2588                                 match = is_ipv6 &&
2589                                     flow6id_match(args->f_id.flow_id6,
2590                                     (ipfw_insn_u32 *) cmd);
2591                                 break;
2592
2593                         case O_EXT_HDR:
2594                                 match = is_ipv6 &&
2595                                     (ext_hd & ((ipfw_insn *) cmd)->arg1);
2596                                 break;
2597
2598                         case O_IP6:
2599                                 match = is_ipv6;
2600                                 break;
2601 #endif
2602
2603                         case O_IP4:
2604                                 match = is_ipv4;
2605                                 break;
2606
2607                         case O_TAG: {
2608                                 struct m_tag *mtag;
2609                                 uint32_t tag = TARG(cmd->arg1, tag);
2610
2611                                 /* Packet is already tagged with this tag? */
2612                                 mtag = m_tag_locate(m, MTAG_IPFW, tag, NULL);
2613
2614                                 /* We have `untag' action when F_NOT flag is
2615                                  * present. And we must remove this mtag from
2616                                  * mbuf and reset `match' to zero (`match' will
2617                                  * be inversed later).
2618                                  * Otherwise we should allocate new mtag and
2619                                  * push it into mbuf.
2620                                  */
2621                                 if (cmd->len & F_NOT) { /* `untag' action */
2622                                         if (mtag != NULL)
2623                                                 m_tag_delete(m, mtag);
2624                                         match = 0;
2625                                 } else {
2626                                         if (mtag == NULL) {
2627                                                 mtag = m_tag_alloc( MTAG_IPFW,
2628                                                     tag, 0, M_NOWAIT);
2629                                                 if (mtag != NULL)
2630                                                         m_tag_prepend(m, mtag);
2631                                         }
2632                                         match = 1;
2633                                 }
2634                                 break;
2635                         }
2636
2637                         case O_FIB: /* try match the specified fib */
2638                                 if (args->f_id.fib == cmd->arg1)
2639                                         match = 1;
2640                                 break;
2641
2642                         case O_SOCKARG: {
2643 #ifndef USERSPACE       /* not supported in userspace */
2644                                 struct inpcb *inp = args->inp;
2645                                 struct inpcbinfo *pi;
2646                                 bool inp_locked = false;
2647
2648                                 if (proto == IPPROTO_TCP)
2649                                         pi = &V_tcbinfo;
2650                                 else if (proto == IPPROTO_UDP)
2651                                         pi = &V_udbinfo;
2652                                 else if (proto == IPPROTO_UDPLITE)
2653                                         pi = &V_ulitecbinfo;
2654                                 else
2655                                         break;
2656
2657                                 /*
2658                                  * XXXRW: so_user_cookie should almost
2659                                  * certainly be inp_user_cookie?
2660                                  */
2661
2662                                 /*
2663                                  * For incoming packet lookup the inpcb
2664                                  * using the src/dest ip/port tuple.
2665                                  */
2666                                 if (is_ipv4 && inp == NULL) {
2667                                         inp = in_pcblookup(pi,
2668                                             src_ip, htons(src_port),
2669                                             dst_ip, htons(dst_port),
2670                                             INPLOOKUP_RLOCKPCB, NULL);
2671                                         inp_locked = true;
2672                                 }
2673 #ifdef INET6
2674                                 if (is_ipv6 && inp == NULL) {
2675                                         inp = in6_pcblookup(pi,
2676                                             &args->f_id.src_ip6,
2677                                             htons(src_port),
2678                                             &args->f_id.dst_ip6,
2679                                             htons(dst_port),
2680                                             INPLOOKUP_RLOCKPCB, NULL);
2681                                         inp_locked = true;
2682                                 }
2683 #endif /* INET6 */
2684                                 if (inp != NULL) {
2685                                         if (inp->inp_socket) {
2686                                                 tablearg =
2687                                                     inp->inp_socket->so_user_cookie;
2688                                                 if (tablearg)
2689                                                         match = 1;
2690                                         }
2691                                         if (inp_locked)
2692                                                 INP_RUNLOCK(inp);
2693                                 }
2694 #endif /* !USERSPACE */
2695                                 break;
2696                         }
2697
2698                         case O_TAGGED: {
2699                                 struct m_tag *mtag;
2700                                 uint32_t tag = TARG(cmd->arg1, tag);
2701
2702                                 if (cmdlen == 1) {
2703                                         match = m_tag_locate(m, MTAG_IPFW,
2704                                             tag, NULL) != NULL;
2705                                         break;
2706                                 }
2707
2708                                 /* we have ranges */
2709                                 for (mtag = m_tag_first(m);
2710                                     mtag != NULL && !match;
2711                                     mtag = m_tag_next(m, mtag)) {
2712                                         uint16_t *p;
2713                                         int i;
2714
2715                                         if (mtag->m_tag_cookie != MTAG_IPFW)
2716                                                 continue;
2717
2718                                         p = ((ipfw_insn_u16 *)cmd)->ports;
2719                                         i = cmdlen - 1;
2720                                         for(; !match && i > 0; i--, p += 2)
2721                                                 match =
2722                                                     mtag->m_tag_id >= p[0] &&
2723                                                     mtag->m_tag_id <= p[1];
2724                                 }
2725                                 break;
2726                         }
2727
2728                         /*
2729                          * The second set of opcodes represents 'actions',
2730                          * i.e. the terminal part of a rule once the packet
2731                          * matches all previous patterns.
2732                          * Typically there is only one action for each rule,
2733                          * and the opcode is stored at the end of the rule
2734                          * (but there are exceptions -- see below).
2735                          *
2736                          * In general, here we set retval and terminate the
2737                          * outer loop (would be a 'break 3' in some language,
2738                          * but we need to set l=0, done=1)
2739                          *
2740                          * Exceptions:
2741                          * O_COUNT and O_SKIPTO actions:
2742                          *   instead of terminating, we jump to the next rule
2743                          *   (setting l=0), or to the SKIPTO target (setting
2744                          *   f/f_len, cmd and l as needed), respectively.
2745                          *
2746                          * O_TAG, O_LOG and O_ALTQ action parameters:
2747                          *   perform some action and set match = 1;
2748                          *
2749                          * O_LIMIT and O_KEEP_STATE: these opcodes are
2750                          *   not real 'actions', and are stored right
2751                          *   before the 'action' part of the rule (one
2752                          *   exception is O_SKIP_ACTION which could be
2753                          *   between these opcodes and 'action' one).
2754                          *   These opcodes try to install an entry in the
2755                          *   state tables; if successful, we continue with
2756                          *   the next opcode (match=1; break;), otherwise
2757                          *   the packet must be dropped (set retval,
2758                          *   break loops with l=0, done=1)
2759                          *
2760                          * O_PROBE_STATE and O_CHECK_STATE: these opcodes
2761                          *   cause a lookup of the state table, and a jump
2762                          *   to the 'action' part of the parent rule
2763                          *   if an entry is found, or
2764                          *   (CHECK_STATE only) a jump to the next rule if
2765                          *   the entry is not found.
2766                          *   The result of the lookup is cached so that
2767                          *   further instances of these opcodes become NOPs.
2768                          *   The jump to the next rule is done by setting
2769                          *   l=0, cmdlen=0.
2770                          *
2771                          * O_SKIP_ACTION: this opcode is not a real 'action'
2772                          *  either, and is stored right before the 'action'
2773                          *  part of the rule, right after the O_KEEP_STATE
2774                          *  opcode. It causes match failure so the real
2775                          *  'action' could be executed only if the rule
2776                          *  is checked via dynamic rule from the state
2777                          *  table, as in such case execution starts
2778                          *  from the true 'action' opcode directly.
2779                          *
2780                          */
2781                         case O_LIMIT:
2782                         case O_KEEP_STATE:
2783                                 if (ipfw_dyn_install_state(chain, f,
2784                                     (ipfw_insn_limit *)cmd, args, ulp,
2785                                     pktlen, &dyn_info, tablearg)) {
2786                                         /* error or limit violation */
2787                                         retval = IP_FW_DENY;
2788                                         l = 0;  /* exit inner loop */
2789                                         done = 1; /* exit outer loop */
2790                                 }
2791                                 match = 1;
2792                                 break;
2793
2794                         case O_PROBE_STATE:
2795                         case O_CHECK_STATE:
2796                                 /*
2797                                  * dynamic rules are checked at the first
2798                                  * keep-state or check-state occurrence,
2799                                  * with the result being stored in dyn_info.
2800                                  * The compiler introduces a PROBE_STATE
2801                                  * instruction for us when we have a
2802                                  * KEEP_STATE (because PROBE_STATE needs
2803                                  * to be run first).
2804                                  */
2805                                 if (DYN_LOOKUP_NEEDED(&dyn_info, cmd) &&
2806                                     (q = ipfw_dyn_lookup_state(args, ulp,
2807                                     pktlen, cmd, &dyn_info)) != NULL) {
2808                                         /*
2809                                          * Found dynamic entry, jump to the
2810                                          * 'action' part of the parent rule
2811                                          * by setting f, cmd, l and clearing
2812                                          * cmdlen.
2813                                          */
2814                                         f = q;
2815                                         f_pos = dyn_info.f_pos;
2816                                         cmd = ACTION_PTR(f);
2817                                         l = f->cmd_len - f->act_ofs;
2818                                         cmdlen = 0;
2819                                         match = 1;
2820                                         break;
2821                                 }
2822                                 /*
2823                                  * Dynamic entry not found. If CHECK_STATE,
2824                                  * skip to next rule, if PROBE_STATE just
2825                                  * ignore and continue with next opcode.
2826                                  */
2827                                 if (cmd->opcode == O_CHECK_STATE)
2828                                         l = 0;  /* exit inner loop */
2829                                 match = 1;
2830                                 break;
2831
2832                         case O_SKIP_ACTION:
2833                                 match = 0;      /* skip to the next rule */
2834                                 l = 0;          /* exit inner loop */
2835                                 break;
2836
2837                         case O_ACCEPT:
2838                                 retval = 0;     /* accept */
2839                                 l = 0;          /* exit inner loop */
2840                                 done = 1;       /* exit outer loop */
2841                                 break;
2842
2843                         case O_PIPE:
2844                         case O_QUEUE:
2845                                 set_match(args, f_pos, chain);
2846                                 args->rule.info = TARG(cmd->arg1, pipe);
2847                                 if (cmd->opcode == O_PIPE)
2848                                         args->rule.info |= IPFW_IS_PIPE;
2849                                 if (V_fw_one_pass)
2850                                         args->rule.info |= IPFW_ONEPASS;
2851                                 retval = IP_FW_DUMMYNET;
2852                                 l = 0;          /* exit inner loop */
2853                                 done = 1;       /* exit outer loop */
2854                                 break;
2855
2856                         case O_DIVERT:
2857                         case O_TEE:
2858                                 if (args->flags & IPFW_ARGS_ETHER)
2859                                         break;  /* not on layer 2 */
2860                                 /* otherwise this is terminal */
2861                                 l = 0;          /* exit inner loop */
2862                                 done = 1;       /* exit outer loop */
2863                                 retval = (cmd->opcode == O_DIVERT) ?
2864                                         IP_FW_DIVERT : IP_FW_TEE;
2865                                 set_match(args, f_pos, chain);
2866                                 args->rule.info = TARG(cmd->arg1, divert);
2867                                 break;
2868
2869                         case O_COUNT:
2870                                 IPFW_INC_RULE_COUNTER(f, pktlen);
2871                                 l = 0;          /* exit inner loop */
2872                                 break;
2873
2874                         case O_SKIPTO:
2875                             IPFW_INC_RULE_COUNTER(f, pktlen);
2876                             f_pos = JUMP(chain, f, cmd->arg1, tablearg, 0);
2877                             /*
2878                              * Skip disabled rules, and re-enter
2879                              * the inner loop with the correct
2880                              * f_pos, f, l and cmd.
2881                              * Also clear cmdlen and skip_or
2882                              */
2883                             for (; f_pos < chain->n_rules - 1 &&
2884                                     (V_set_disable &
2885                                      (1 << chain->map[f_pos]->set));
2886                                     f_pos++)
2887                                 ;
2888                             /* Re-enter the inner loop at the skipto rule. */
2889                             f = chain->map[f_pos];
2890                             l = f->cmd_len;
2891                             cmd = f->cmd;
2892                             match = 1;
2893                             cmdlen = 0;
2894                             skip_or = 0;
2895                             continue;
2896                             break;      /* not reached */
2897
2898                         case O_CALLRETURN: {
2899                                 /*
2900                                  * Implementation of `subroutine' call/return,
2901                                  * in the stack carried in an mbuf tag. This
2902                                  * is different from `skipto' in that any call
2903                                  * address is possible (`skipto' must prevent
2904                                  * backward jumps to avoid endless loops).
2905                                  * We have `return' action when F_NOT flag is
2906                                  * present. The `m_tag_id' field is used as
2907                                  * stack pointer.
2908                                  */
2909                                 struct m_tag *mtag;
2910                                 uint16_t jmpto, *stack;
2911
2912 #define IS_CALL         ((cmd->len & F_NOT) == 0)
2913 #define IS_RETURN       ((cmd->len & F_NOT) != 0)
2914                                 /*
2915                                  * Hand-rolled version of m_tag_locate() with
2916                                  * wildcard `type'.
2917                                  * If not already tagged, allocate new tag.
2918                                  */
2919                                 mtag = m_tag_first(m);
2920                                 while (mtag != NULL) {
2921                                         if (mtag->m_tag_cookie ==
2922                                             MTAG_IPFW_CALL)
2923                                                 break;
2924                                         mtag = m_tag_next(m, mtag);
2925                                 }
2926                                 if (mtag == NULL && IS_CALL) {
2927                                         mtag = m_tag_alloc(MTAG_IPFW_CALL, 0,
2928                                             IPFW_CALLSTACK_SIZE *
2929                                             sizeof(uint16_t), M_NOWAIT);
2930                                         if (mtag != NULL)
2931                                                 m_tag_prepend(m, mtag);
2932                                 }
2933
2934                                 /*
2935                                  * On error both `call' and `return' just
2936                                  * continue with next rule.
2937                                  */
2938                                 if (IS_RETURN && (mtag == NULL ||
2939                                     mtag->m_tag_id == 0)) {
2940                                         l = 0;          /* exit inner loop */
2941                                         break;
2942                                 }
2943                                 if (IS_CALL && (mtag == NULL ||
2944                                     mtag->m_tag_id >= IPFW_CALLSTACK_SIZE)) {
2945                                         printf("ipfw: call stack error, "
2946                                             "go to next rule\n");
2947                                         l = 0;          /* exit inner loop */
2948                                         break;
2949                                 }
2950
2951                                 IPFW_INC_RULE_COUNTER(f, pktlen);
2952                                 stack = (uint16_t *)(mtag + 1);
2953
2954                                 /*
2955                                  * The `call' action may use cached f_pos
2956                                  * (in f->next_rule), whose version is written
2957                                  * in f->next_rule.
2958                                  * The `return' action, however, doesn't have
2959                                  * fixed jump address in cmd->arg1 and can't use
2960                                  * cache.
2961                                  */
2962                                 if (IS_CALL) {
2963                                         stack[mtag->m_tag_id] = f->rulenum;
2964                                         mtag->m_tag_id++;
2965                                         f_pos = JUMP(chain, f, cmd->arg1,
2966                                             tablearg, 1);
2967                                 } else {        /* `return' action */
2968                                         mtag->m_tag_id--;
2969                                         jmpto = stack[mtag->m_tag_id] + 1;
2970                                         f_pos = ipfw_find_rule(chain, jmpto, 0);
2971                                 }
2972
2973                                 /*
2974                                  * Skip disabled rules, and re-enter
2975                                  * the inner loop with the correct
2976                                  * f_pos, f, l and cmd.
2977                                  * Also clear cmdlen and skip_or
2978                                  */
2979                                 for (; f_pos < chain->n_rules - 1 &&
2980                                     (V_set_disable &
2981                                     (1 << chain->map[f_pos]->set)); f_pos++)
2982                                         ;
2983                                 /* Re-enter the inner loop at the dest rule. */
2984                                 f = chain->map[f_pos];
2985                                 l = f->cmd_len;
2986                                 cmd = f->cmd;
2987                                 cmdlen = 0;
2988                                 skip_or = 0;
2989                                 continue;
2990                                 break;  /* NOTREACHED */
2991                         }
2992 #undef IS_CALL
2993 #undef IS_RETURN
2994
2995                         case O_REJECT:
2996                                 /*
2997                                  * Drop the packet and send a reject notice
2998                                  * if the packet is not ICMP (or is an ICMP
2999                                  * query), and it is not multicast/broadcast.
3000                                  */
3001                                 if (hlen > 0 && is_ipv4 && offset == 0 &&
3002                                     (proto != IPPROTO_ICMP ||
3003                                      is_icmp_query(ICMP(ulp))) &&
3004                                     !(m->m_flags & (M_BCAST|M_MCAST)) &&
3005                                     !IN_MULTICAST(ntohl(dst_ip.s_addr))) {
3006                                         send_reject(args, cmd->arg1, iplen, ip);
3007                                         m = args->m;
3008                                 }
3009                                 /* FALLTHROUGH */
3010 #ifdef INET6
3011                         case O_UNREACH6:
3012                                 if (hlen > 0 && is_ipv6 &&
3013                                     ((offset & IP6F_OFF_MASK) == 0) &&
3014                                     (proto != IPPROTO_ICMPV6 ||
3015                                      (is_icmp6_query(icmp6_type) == 1)) &&
3016                                     !(m->m_flags & (M_BCAST|M_MCAST)) &&
3017                                     !IN6_IS_ADDR_MULTICAST(
3018                                         &args->f_id.dst_ip6)) {
3019                                         send_reject6(args,
3020                                             cmd->opcode == O_REJECT ?
3021                                             map_icmp_unreach(cmd->arg1):
3022                                             cmd->arg1, hlen,
3023                                             (struct ip6_hdr *)ip);
3024                                         m = args->m;
3025                                 }
3026                                 /* FALLTHROUGH */
3027 #endif
3028                         case O_DENY:
3029                                 retval = IP_FW_DENY;
3030                                 l = 0;          /* exit inner loop */
3031                                 done = 1;       /* exit outer loop */
3032                                 break;
3033
3034                         case O_FORWARD_IP:
3035                                 if (args->flags & IPFW_ARGS_ETHER)
3036                                         break;  /* not valid on layer2 pkts */
3037                                 if (q != f ||
3038                                     dyn_info.direction == MATCH_FORWARD) {
3039                                     struct sockaddr_in *sa;
3040
3041                                     sa = &(((ipfw_insn_sa *)cmd)->sa);
3042                                     if (sa->sin_addr.s_addr == INADDR_ANY) {
3043 #ifdef INET6
3044                                         /*
3045                                          * We use O_FORWARD_IP opcode for
3046                                          * fwd rule with tablearg, but tables
3047                                          * now support IPv6 addresses. And
3048                                          * when we are inspecting IPv6 packet,
3049                                          * we can use nh6 field from
3050                                          * table_value as next_hop6 address.
3051                                          */
3052                                         if (is_ipv6) {
3053                                                 struct ip_fw_nh6 *nh6;
3054
3055                                                 args->flags |= IPFW_ARGS_NH6;
3056                                                 nh6 = &args->hopstore6;
3057                                                 nh6->sin6_addr = TARG_VAL(
3058                                                     chain, tablearg, nh6);
3059                                                 nh6->sin6_port = sa->sin_port;
3060                                                 nh6->sin6_scope_id = TARG_VAL(
3061                                                     chain, tablearg, zoneid);
3062                                         } else
3063 #endif
3064                                         {
3065                                                 args->flags |= IPFW_ARGS_NH4;
3066                                                 args->hopstore.sin_port =
3067                                                     sa->sin_port;
3068                                                 sa = &args->hopstore;
3069                                                 sa->sin_family = AF_INET;
3070                                                 sa->sin_len = sizeof(*sa);
3071                                                 sa->sin_addr.s_addr = htonl(
3072                                                     TARG_VAL(chain, tablearg,
3073                                                     nh4));
3074                                         }
3075                                     } else {
3076                                             args->flags |= IPFW_ARGS_NH4PTR;
3077                                             args->next_hop = sa;
3078                                     }
3079                                 }
3080                                 retval = IP_FW_PASS;
3081                                 l = 0;          /* exit inner loop */
3082                                 done = 1;       /* exit outer loop */
3083                                 break;
3084
3085 #ifdef INET6
3086                         case O_FORWARD_IP6:
3087                                 if (args->flags & IPFW_ARGS_ETHER)
3088                                         break;  /* not valid on layer2 pkts */
3089                                 if (q != f ||
3090                                     dyn_info.direction == MATCH_FORWARD) {
3091                                         struct sockaddr_in6 *sin6;
3092
3093                                         sin6 = &(((ipfw_insn_sa6 *)cmd)->sa);
3094                                         args->flags |= IPFW_ARGS_NH6PTR;
3095                                         args->next_hop6 = sin6;
3096                                 }
3097                                 retval = IP_FW_PASS;
3098                                 l = 0;          /* exit inner loop */
3099                                 done = 1;       /* exit outer loop */
3100                                 break;
3101 #endif
3102
3103                         case O_NETGRAPH:
3104                         case O_NGTEE:
3105                                 set_match(args, f_pos, chain);
3106                                 args->rule.info = TARG(cmd->arg1, netgraph);
3107                                 if (V_fw_one_pass)
3108                                         args->rule.info |= IPFW_ONEPASS;
3109                                 retval = (cmd->opcode == O_NETGRAPH) ?
3110                                     IP_FW_NETGRAPH : IP_FW_NGTEE;
3111                                 l = 0;          /* exit inner loop */
3112                                 done = 1;       /* exit outer loop */
3113                                 break;
3114
3115                         case O_SETFIB: {
3116                                 uint32_t fib;
3117
3118                                 IPFW_INC_RULE_COUNTER(f, pktlen);
3119                                 fib = TARG(cmd->arg1, fib) & 0x7FFF;
3120                                 if (fib >= rt_numfibs)
3121                                         fib = 0;
3122                                 M_SETFIB(m, fib);
3123                                 args->f_id.fib = fib; /* XXX */
3124                                 l = 0;          /* exit inner loop */
3125                                 break;
3126                         }
3127
3128                         case O_SETDSCP: {
3129                                 uint16_t code;
3130
3131                                 code = TARG(cmd->arg1, dscp) & 0x3F;
3132                                 l = 0;          /* exit inner loop */
3133                                 if (is_ipv4) {
3134                                         uint16_t old;
3135
3136                                         old = *(uint16_t *)ip;
3137                                         ip->ip_tos = (code << 2) |
3138                                             (ip->ip_tos & 0x03);
3139                                         ip->ip_sum = cksum_adjust(ip->ip_sum,
3140                                             old, *(uint16_t *)ip);
3141                                 } else if (is_ipv6) {
3142                                         uint8_t *v;
3143
3144                                         v = &((struct ip6_hdr *)ip)->ip6_vfc;
3145                                         *v = (*v & 0xF0) | (code >> 2);
3146                                         v++;
3147                                         *v = (*v & 0x3F) | ((code & 0x03) << 6);
3148                                 } else
3149                                         break;
3150
3151                                 IPFW_INC_RULE_COUNTER(f, pktlen);
3152                                 break;
3153                         }
3154
3155                         case O_NAT:
3156                                 l = 0;          /* exit inner loop */
3157                                 done = 1;       /* exit outer loop */
3158                                 /*
3159                                  * Ensure that we do not invoke NAT handler for
3160                                  * non IPv4 packets. Libalias expects only IPv4.
3161                                  */
3162                                 if (!is_ipv4 || !IPFW_NAT_LOADED) {
3163                                     retval = IP_FW_DENY;
3164                                     break;
3165                                 }
3166
3167                                 struct cfg_nat *t;
3168                                 int nat_id;
3169
3170                                 args->rule.info = 0;
3171                                 set_match(args, f_pos, chain);
3172                                 /* Check if this is 'global' nat rule */
3173                                 if (cmd->arg1 == IP_FW_NAT44_GLOBAL) {
3174                                         retval = ipfw_nat_ptr(args, NULL, m);
3175                                         break;
3176                                 }
3177                                 t = ((ipfw_insn_nat *)cmd)->nat;
3178                                 if (t == NULL) {
3179                                         nat_id = TARG(cmd->arg1, nat);
3180                                         t = (*lookup_nat_ptr)(&chain->nat, nat_id);
3181
3182                                         if (t == NULL) {
3183                                             retval = IP_FW_DENY;
3184                                             break;
3185                                         }
3186                                         if (cmd->arg1 != IP_FW_TARG)
3187                                             ((ipfw_insn_nat *)cmd)->nat = t;
3188                                 }
3189                                 retval = ipfw_nat_ptr(args, t, m);
3190                                 break;
3191
3192                         case O_REASS: {
3193                                 int ip_off;
3194
3195                                 l = 0;  /* in any case exit inner loop */
3196                                 if (is_ipv6) /* IPv6 is not supported yet */
3197                                         break;
3198                                 IPFW_INC_RULE_COUNTER(f, pktlen);
3199                                 ip_off = ntohs(ip->ip_off);
3200
3201                                 /* if not fragmented, go to next rule */
3202                                 if ((ip_off & (IP_MF | IP_OFFMASK)) == 0)
3203                                     break;
3204
3205                                 args->m = m = ip_reass(m);
3206
3207                                 /*
3208                                  * do IP header checksum fixup.
3209                                  */
3210                                 if (m == NULL) { /* fragment got swallowed */
3211                                     retval = IP_FW_DENY;
3212                                 } else { /* good, packet complete */
3213                                     int hlen;
3214
3215                                     ip = mtod(m, struct ip *);
3216                                     hlen = ip->ip_hl << 2;
3217                                     ip->ip_sum = 0;
3218                                     if (hlen == sizeof(struct ip))
3219                                         ip->ip_sum = in_cksum_hdr(ip);
3220                                     else
3221                                         ip->ip_sum = in_cksum(m, hlen);
3222                                     retval = IP_FW_REASS;
3223                                     args->rule.info = 0;
3224                                     set_match(args, f_pos, chain);
3225                                 }
3226                                 done = 1;       /* exit outer loop */
3227                                 break;
3228                         }
3229                         case O_EXTERNAL_ACTION:
3230                                 l = 0; /* in any case exit inner loop */
3231                                 retval = ipfw_run_eaction(chain, args,
3232                                     cmd, &done);
3233                                 /*
3234                                  * If both @retval and @done are zero,
3235                                  * consider this as rule matching and
3236                                  * update counters.
3237                                  */
3238                                 if (retval == 0 && done == 0) {
3239                                         IPFW_INC_RULE_COUNTER(f, pktlen);
3240                                         /*
3241                                          * Reset the result of the last
3242                                          * dynamic state lookup.
3243                                          * External action can change
3244                                          * @args content, and it may be
3245                                          * used for new state lookup later.
3246                                          */
3247                                         DYN_INFO_INIT(&dyn_info);
3248                                 }
3249                                 break;
3250
3251                         default:
3252                                 panic("-- unknown opcode %d\n", cmd->opcode);
3253                         } /* end of switch() on opcodes */
3254                         /*
3255                          * if we get here with l=0, then match is irrelevant.
3256                          */
3257
3258                         if (cmd->len & F_NOT)
3259                                 match = !match;
3260
3261                         if (match) {
3262                                 if (cmd->len & F_OR)
3263                                         skip_or = 1;
3264                         } else {
3265                                 if (!(cmd->len & F_OR)) /* not an OR block, */
3266                                         break;          /* try next rule    */
3267                         }
3268
3269                 }       /* end of inner loop, scan opcodes */
3270 #undef PULLUP_LEN
3271 #undef PULLUP_LEN_LOCKED
3272
3273                 if (done)
3274                         break;
3275
3276 /* next_rule:; */       /* try next rule                */
3277
3278         }               /* end of outer for, scan rules */
3279
3280         if (done) {
3281                 struct ip_fw *rule = chain->map[f_pos];
3282                 /* Update statistics */
3283                 IPFW_INC_RULE_COUNTER(rule, pktlen);
3284                 IPFW_PROBE(rule__matched, retval,
3285                     is_ipv4 ? AF_INET : AF_INET6,
3286                     is_ipv4 ? (uintptr_t)&src_ip :
3287                         (uintptr_t)&args->f_id.src_ip6,
3288                     is_ipv4 ? (uintptr_t)&dst_ip :
3289                         (uintptr_t)&args->f_id.dst_ip6,
3290                     args, rule);
3291         } else {
3292                 retval = IP_FW_DENY;
3293                 printf("ipfw: ouch!, skip past end of rules, denying packet\n");
3294         }
3295         IPFW_PF_RUNLOCK(chain);
3296 #ifdef __FreeBSD__
3297         if (ucred_cache != NULL)
3298                 crfree(ucred_cache);
3299 #endif
3300         return (retval);
3301
3302 pullup_failed:
3303         if (V_fw_verbose)
3304                 printf("ipfw: pullup failed\n");
3305         return (IP_FW_DENY);
3306 }
3307
3308 /*
3309  * Set maximum number of tables that can be used in given VNET ipfw instance.
3310  */
3311 #ifdef SYSCTL_NODE
3312 static int
3313 sysctl_ipfw_table_num(SYSCTL_HANDLER_ARGS)
3314 {
3315         int error;
3316         unsigned int ntables;
3317
3318         ntables = V_fw_tables_max;
3319
3320         error = sysctl_handle_int(oidp, &ntables, 0, req);
3321         /* Read operation or some error */
3322         if ((error != 0) || (req->newptr == NULL))
3323                 return (error);
3324
3325         return (ipfw_resize_tables(&V_layer3_chain, ntables));
3326 }
3327
3328 /*
3329  * Switches table namespace between global and per-set.
3330  */
3331 static int
3332 sysctl_ipfw_tables_sets(SYSCTL_HANDLER_ARGS)
3333 {
3334         int error;
3335         unsigned int sets;
3336
3337         sets = V_fw_tables_sets;
3338
3339         error = sysctl_handle_int(oidp, &sets, 0, req);
3340         /* Read operation or some error */
3341         if ((error != 0) || (req->newptr == NULL))
3342                 return (error);
3343
3344         return (ipfw_switch_tables_namespace(&V_layer3_chain, sets));
3345 }
3346 #endif
3347
3348 /*
3349  * Module and VNET glue
3350  */
3351
3352 /*
3353  * Stuff that must be initialised only on boot or module load
3354  */
3355 static int
3356 ipfw_init(void)
3357 {
3358         int error = 0;
3359
3360         /*
3361          * Only print out this stuff the first time around,
3362          * when called from the sysinit code.
3363          */
3364         printf("ipfw2 "
3365 #ifdef INET6
3366                 "(+ipv6) "
3367 #endif
3368                 "initialized, divert %s, nat %s, "
3369                 "default to %s, logging ",
3370 #ifdef IPDIVERT
3371                 "enabled",
3372 #else
3373                 "loadable",
3374 #endif
3375 #ifdef IPFIREWALL_NAT
3376                 "enabled",
3377 #else
3378                 "loadable",
3379 #endif
3380                 default_to_accept ? "accept" : "deny");
3381
3382         /*
3383          * Note: V_xxx variables can be accessed here but the vnet specific
3384          * initializer may not have been called yet for the VIMAGE case.
3385          * Tuneables will have been processed. We will print out values for
3386          * the default vnet.
3387          * XXX This should all be rationalized AFTER 8.0
3388          */
3389         if (V_fw_verbose == 0)
3390                 printf("disabled\n");
3391         else if (V_verbose_limit == 0)
3392                 printf("unlimited\n");
3393         else
3394                 printf("limited to %d packets/entry by default\n",
3395                     V_verbose_limit);
3396
3397         /* Check user-supplied table count for validness */
3398         if (default_fw_tables > IPFW_TABLES_MAX)
3399           default_fw_tables = IPFW_TABLES_MAX;
3400
3401         ipfw_init_sopt_handler();
3402         ipfw_init_obj_rewriter();
3403         ipfw_iface_init();
3404         return (error);
3405 }
3406
3407 /*
3408  * Called for the removal of the last instance only on module unload.
3409  */
3410 static void
3411 ipfw_destroy(void)
3412 {
3413
3414         ipfw_iface_destroy();
3415         ipfw_destroy_sopt_handler();
3416         ipfw_destroy_obj_rewriter();
3417         printf("IP firewall unloaded\n");
3418 }
3419
3420 /*
3421  * Stuff that must be initialized for every instance
3422  * (including the first of course).
3423  */
3424 static int
3425 vnet_ipfw_init(const void *unused)
3426 {
3427         int error, first;
3428         struct ip_fw *rule = NULL;
3429         struct ip_fw_chain *chain;
3430
3431         chain = &V_layer3_chain;
3432
3433         first = IS_DEFAULT_VNET(curvnet) ? 1 : 0;
3434
3435         /* First set up some values that are compile time options */
3436         V_autoinc_step = 100;   /* bounded to 1..1000 in add_rule() */
3437         V_fw_deny_unknown_exthdrs = 1;
3438 #ifdef IPFIREWALL_VERBOSE
3439         V_fw_verbose = 1;
3440 #endif
3441 #ifdef IPFIREWALL_VERBOSE_LIMIT
3442         V_verbose_limit = IPFIREWALL_VERBOSE_LIMIT;
3443 #endif
3444 #ifdef IPFIREWALL_NAT
3445         LIST_INIT(&chain->nat);
3446 #endif
3447
3448         /* Init shared services hash table */
3449         ipfw_init_srv(chain);
3450
3451         ipfw_init_counters();
3452         /* Set initial number of tables */
3453         V_fw_tables_max = default_fw_tables;
3454         error = ipfw_init_tables(chain, first);
3455         if (error) {
3456                 printf("ipfw2: setting up tables failed\n");
3457                 free(chain->map, M_IPFW);
3458                 free(rule, M_IPFW);
3459                 return (ENOSPC);
3460         }
3461
3462         IPFW_LOCK_INIT(chain);
3463
3464         /* fill and insert the default rule */
3465         rule = ipfw_alloc_rule(chain, sizeof(struct ip_fw));
3466         rule->flags |= IPFW_RULE_NOOPT;
3467         rule->cmd_len = 1;
3468         rule->cmd[0].len = 1;
3469         rule->cmd[0].opcode = default_to_accept ? O_ACCEPT : O_DENY;
3470         chain->default_rule = rule;
3471         ipfw_add_protected_rule(chain, rule, 0);
3472
3473         ipfw_dyn_init(chain);
3474         ipfw_eaction_init(chain, first);
3475 #ifdef LINEAR_SKIPTO
3476         ipfw_init_skipto_cache(chain);
3477 #endif
3478         ipfw_bpf_init(first);
3479
3480         /* First set up some values that are compile time options */
3481         V_ipfw_vnet_ready = 1;          /* Open for business */
3482
3483         /*
3484          * Hook the sockopt handler and pfil hooks for ipv4 and ipv6.
3485          * Even if the latter two fail we still keep the module alive
3486          * because the sockopt and layer2 paths are still useful.
3487          * ipfw[6]_hook return 0 on success, ENOENT on failure,
3488          * so we can ignore the exact return value and just set a flag.
3489          *
3490          * Note that V_fw[6]_enable are manipulated by a SYSCTL_PROC so
3491          * changes in the underlying (per-vnet) variables trigger
3492          * immediate hook()/unhook() calls.
3493          * In layer2 we have the same behaviour, except that V_ether_ipfw
3494          * is checked on each packet because there are no pfil hooks.
3495          */
3496         V_ip_fw_ctl_ptr = ipfw_ctl3;
3497         error = ipfw_attach_hooks();
3498         return (error);
3499 }
3500
3501 /*
3502  * Called for the removal of each instance.
3503  */
3504 static int
3505 vnet_ipfw_uninit(const void *unused)
3506 {
3507         struct ip_fw *reap;
3508         struct ip_fw_chain *chain = &V_layer3_chain;
3509         int i, last;
3510
3511         V_ipfw_vnet_ready = 0; /* tell new callers to go away */
3512         /*
3513          * disconnect from ipv4, ipv6, layer2 and sockopt.
3514          * Then grab, release and grab again the WLOCK so we make
3515          * sure the update is propagated and nobody will be in.
3516          */
3517         ipfw_detach_hooks();
3518         V_ip_fw_ctl_ptr = NULL;
3519
3520         last = IS_DEFAULT_VNET(curvnet) ? 1 : 0;
3521
3522         IPFW_UH_WLOCK(chain);
3523         IPFW_UH_WUNLOCK(chain);
3524
3525         ipfw_dyn_uninit(0);     /* run the callout_drain */
3526
3527         IPFW_UH_WLOCK(chain);
3528
3529         reap = NULL;
3530         IPFW_WLOCK(chain);
3531         for (i = 0; i < chain->n_rules; i++)
3532                 ipfw_reap_add(chain, &reap, chain->map[i]);
3533         free(chain->map, M_IPFW);
3534 #ifdef LINEAR_SKIPTO
3535         ipfw_destroy_skipto_cache(chain);
3536 #endif
3537         IPFW_WUNLOCK(chain);
3538         IPFW_UH_WUNLOCK(chain);
3539         ipfw_destroy_tables(chain, last);
3540         ipfw_eaction_uninit(chain, last);
3541         if (reap != NULL)
3542                 ipfw_reap_rules(reap);
3543         vnet_ipfw_iface_destroy(chain);
3544         ipfw_destroy_srv(chain);
3545         IPFW_LOCK_DESTROY(chain);
3546         ipfw_dyn_uninit(1);     /* free the remaining parts */
3547         ipfw_destroy_counters();
3548         ipfw_bpf_uninit(last);
3549         return (0);
3550 }
3551
3552 /*
3553  * Module event handler.
3554  * In general we have the choice of handling most of these events by the
3555  * event handler or by the (VNET_)SYS(UN)INIT handlers. I have chosen to
3556  * use the SYSINIT handlers as they are more capable of expressing the
3557  * flow of control during module and vnet operations, so this is just
3558  * a skeleton. Note there is no SYSINIT equivalent of the module
3559  * SHUTDOWN handler, but we don't have anything to do in that case anyhow.
3560  */
3561 static int
3562 ipfw_modevent(module_t mod, int type, void *unused)
3563 {
3564         int err = 0;
3565
3566         switch (type) {
3567         case MOD_LOAD:
3568                 /* Called once at module load or
3569                  * system boot if compiled in. */
3570                 break;
3571         case MOD_QUIESCE:
3572                 /* Called before unload. May veto unloading. */
3573                 break;
3574         case MOD_UNLOAD:
3575                 /* Called during unload. */
3576                 break;
3577         case MOD_SHUTDOWN:
3578                 /* Called during system shutdown. */
3579                 break;
3580         default:
3581                 err = EOPNOTSUPP;
3582                 break;
3583         }
3584         return err;
3585 }
3586
3587 static moduledata_t ipfwmod = {
3588         "ipfw",
3589         ipfw_modevent,
3590         0
3591 };
3592
3593 /* Define startup order. */
3594 #define IPFW_SI_SUB_FIREWALL    SI_SUB_PROTO_FIREWALL
3595 #define IPFW_MODEVENT_ORDER     (SI_ORDER_ANY - 255) /* On boot slot in here. */
3596 #define IPFW_MODULE_ORDER       (IPFW_MODEVENT_ORDER + 1) /* A little later. */
3597 #define IPFW_VNET_ORDER         (IPFW_MODEVENT_ORDER + 2) /* Later still. */
3598
3599 DECLARE_MODULE(ipfw, ipfwmod, IPFW_SI_SUB_FIREWALL, IPFW_MODEVENT_ORDER);
3600 FEATURE(ipfw_ctl3, "ipfw new sockopt calls");
3601 MODULE_VERSION(ipfw, 3);
3602 /* should declare some dependencies here */
3603
3604 /*
3605  * Starting up. Done in order after ipfwmod() has been called.
3606  * VNET_SYSINIT is also called for each existing vnet and each new vnet.
3607  */
3608 SYSINIT(ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER,
3609             ipfw_init, NULL);
3610 VNET_SYSINIT(vnet_ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER,
3611             vnet_ipfw_init, NULL);
3612
3613 /*
3614  * Closing up shop. These are done in REVERSE ORDER, but still
3615  * after ipfwmod() has been called. Not called on reboot.
3616  * VNET_SYSUNINIT is also called for each exiting vnet as it exits.
3617  * or when the module is unloaded.
3618  */
3619 SYSUNINIT(ipfw_destroy, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER,
3620             ipfw_destroy, NULL);
3621 VNET_SYSUNINIT(vnet_ipfw_uninit, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER,
3622             vnet_ipfw_uninit, NULL);
3623 /* end of file */