ip_fw.h revision 146894
1193267Sjkim/*- 2193267Sjkim * Copyright (c) 2002 Luigi Rizzo, Universita` di Pisa 3193267Sjkim * 4193267Sjkim * Redistribution and use in source and binary forms, with or without 5193267Sjkim * modification, are permitted provided that the following conditions 6193267Sjkim * are met: 7316303Sjkim * 1. Redistributions of source code must retain the above copyright 8316303Sjkim * notice, this list of conditions and the following disclaimer. 9316303Sjkim * 2. Redistributions in binary form must reproduce the above copyright 10316303Sjkim * notice, this list of conditions and the following disclaimer in the 11316303Sjkim * documentation and/or other materials provided with the distribution. 12193267Sjkim * 13193267Sjkim * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14316303Sjkim * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15316303Sjkim * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16316303Sjkim * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17316303Sjkim * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18316303Sjkim * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19316303Sjkim * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20316303Sjkim * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21316303Sjkim * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22316303Sjkim * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23316303Sjkim * SUCH DAMAGE. 24316303Sjkim * 25316303Sjkim * $FreeBSD: head/sys/netinet/ip_fw.h 146894 2005-06-03 01:10:28Z mlaier $ 26316303Sjkim */ 27316303Sjkim 28316303Sjkim#ifndef _IPFW2_H 29316303Sjkim#define _IPFW2_H 30316303Sjkim 31316303Sjkim/* 32316303Sjkim * The kernel representation of ipfw rules is made of a list of 33316303Sjkim * 'instructions' (for all practical purposes equivalent to BPF 34316303Sjkim * instructions), which specify which fields of the packet 35316303Sjkim * (or its metadata) should be analysed. 36316303Sjkim * 37316303Sjkim * Each instruction is stored in a structure which begins with 38316303Sjkim * "ipfw_insn", and can contain extra fields depending on the 39316303Sjkim * instruction type (listed below). 40316303Sjkim * Note that the code is written so that individual instructions 41316303Sjkim * have a size which is a multiple of 32 bits. This means that, if 42316303Sjkim * such structures contain pointers or other 64-bit entities, 43316303Sjkim * (there is just one instance now) they may end up unaligned on 44316303Sjkim * 64-bit architectures, so the must be handled with care. 45316303Sjkim * 46316303Sjkim * "enum ipfw_opcodes" are the opcodes supported. We can have up 47316303Sjkim * to 256 different opcodes. When adding new opcodes, they should 48316303Sjkim * be appended to the end of the opcode list before O_LAST_OPCODE, 49316303Sjkim * this will prevent the ABI from being broken, otherwise users 50316303Sjkim * will have to recompile ipfw(8) when they update the kernel. 51316303Sjkim */ 52316303Sjkim 53316303Sjkimenum ipfw_opcodes { /* arguments (4 byte each) */ 54316303Sjkim O_NOP, 55316303Sjkim 56316303Sjkim O_IP_SRC, /* u32 = IP */ 57316303Sjkim O_IP_SRC_MASK, /* ip = IP/mask */ 58316303Sjkim O_IP_SRC_ME, /* none */ 59316303Sjkim O_IP_SRC_SET, /* u32=base, arg1=len, bitmap */ 60316303Sjkim 61316303Sjkim O_IP_DST, /* u32 = IP */ 62316303Sjkim O_IP_DST_MASK, /* ip = IP/mask */ 63316303Sjkim O_IP_DST_ME, /* none */ 64316303Sjkim O_IP_DST_SET, /* u32=base, arg1=len, bitmap */ 65316303Sjkim 66316303Sjkim O_IP_SRCPORT, /* (n)port list:mask 4 byte ea */ 67316303Sjkim O_IP_DSTPORT, /* (n)port list:mask 4 byte ea */ 68316303Sjkim O_PROTO, /* arg1=protocol */ 69316303Sjkim 70316303Sjkim O_MACADDR2, /* 2 mac addr:mask */ 71316303Sjkim O_MAC_TYPE, /* same as srcport */ 72316303Sjkim 73316303Sjkim O_LAYER2, /* none */ 74316303Sjkim O_IN, /* none */ 75316303Sjkim O_FRAG, /* none */ 76316303Sjkim 77316303Sjkim O_RECV, /* none */ 78316303Sjkim O_XMIT, /* none */ 79316303Sjkim O_VIA, /* none */ 80316303Sjkim 81316303Sjkim O_IPOPT, /* arg1 = 2*u8 bitmap */ 82316303Sjkim O_IPLEN, /* arg1 = len */ 83316303Sjkim O_IPID, /* arg1 = id */ 84316303Sjkim 85316303Sjkim O_IPTOS, /* arg1 = id */ 86316303Sjkim O_IPPRECEDENCE, /* arg1 = precedence << 5 */ 87316303Sjkim O_IPTTL, /* arg1 = TTL */ 88316303Sjkim 89316303Sjkim O_IPVER, /* arg1 = version */ 90316303Sjkim O_UID, /* u32 = id */ 91316303Sjkim O_GID, /* u32 = id */ 92316303Sjkim O_ESTAB, /* none (tcp established) */ 93316303Sjkim O_TCPFLAGS, /* arg1 = 2*u8 bitmap */ 94316303Sjkim O_TCPWIN, /* arg1 = desired win */ 95316303Sjkim O_TCPSEQ, /* u32 = desired seq. */ 96316303Sjkim O_TCPACK, /* u32 = desired seq. */ 97316303Sjkim O_ICMPTYPE, /* u32 = icmp bitmap */ 98316303Sjkim O_TCPOPTS, /* arg1 = 2*u8 bitmap */ 99316303Sjkim 100316303Sjkim O_VERREVPATH, /* none */ 101316303Sjkim O_VERSRCREACH, /* none */ 102316303Sjkim 103316303Sjkim O_PROBE_STATE, /* none */ 104316303Sjkim O_KEEP_STATE, /* none */ 105316303Sjkim O_LIMIT, /* ipfw_insn_limit */ 106316303Sjkim O_LIMIT_PARENT, /* dyn_type, not an opcode. */ 107316303Sjkim 108316303Sjkim /* 109316303Sjkim * These are really 'actions'. 110316303Sjkim */ 111316303Sjkim 112316303Sjkim O_LOG, /* ipfw_insn_log */ 113316303Sjkim O_PROB, /* u32 = match probability */ 114316303Sjkim 115316303Sjkim O_CHECK_STATE, /* none */ 116316303Sjkim O_ACCEPT, /* none */ 117316303Sjkim O_DENY, /* none */ 118316303Sjkim O_REJECT, /* arg1=icmp arg (same as deny) */ 119217365Sjkim O_COUNT, /* none */ 120217365Sjkim O_SKIPTO, /* arg1=next rule number */ 121217365Sjkim O_PIPE, /* arg1=pipe number */ 122217365Sjkim O_QUEUE, /* arg1=queue number */ 123217365Sjkim O_DIVERT, /* arg1=port number */ 124217365Sjkim O_TEE, /* arg1=port number */ 125217365Sjkim O_FORWARD_IP, /* fwd sockaddr */ 126217365Sjkim O_FORWARD_MAC, /* fwd mac */ 127217365Sjkim 128217365Sjkim /* 129217365Sjkim * More opcodes. 130217365Sjkim */ 131217365Sjkim O_IPSEC, /* has ipsec history */ 132217365Sjkim O_IP_SRC_LOOKUP, /* arg1=table number, u32=value */ 133193267Sjkim O_IP_DST_LOOKUP, /* arg1=table number, u32=value */ 134316303Sjkim O_ANTISPOOF, /* none */ 135316303Sjkim O_JAIL, /* u32 = id */ 136316303Sjkim O_ALTQ, /* u32 = altq classif. qid */ 137316303Sjkim O_DIVERTED, /* arg1=bitmap (1:loop, 2:out) */ 138316303Sjkim O_TCPDATALEN, /* arg1 = tcp data len */ 139316303Sjkim O_IP6_SRC, /* address without mask */ 140316303Sjkim O_IP6_SRC_ME, /* my addresses */ 141316303Sjkim O_IP6_SRC_MASK, /* address with the mask */ 142316303Sjkim O_IP6_DST, 143316303Sjkim O_IP6_DST_ME, 144316303Sjkim O_IP6_DST_MASK, 145316303Sjkim O_FLOW6ID, /* for flow id tag in the ipv6 pkt */ 146316303Sjkim O_ICMP6TYPE, /* icmp6 packet type filtering */ 147217365Sjkim O_EXT_HDR, /* filtering for ipv6 extension header */ 148217365Sjkim O_IP6, 149193267Sjkim 150316303Sjkim /* 151193267Sjkim * actions for ng_ipfw 152193267Sjkim */ 153193267Sjkim O_NETGRAPH, /* send to ng_ipfw */ 154193267Sjkim O_NGTEE, /* copy to ng_ipfw */ 155193267Sjkim 156193267Sjkim O_IP4, 157193267Sjkim 158193267Sjkim O_LAST_OPCODE /* not an opcode! */ 159193267Sjkim}; 160193267Sjkim 161193267Sjkim/* 162193341Sjkim * The extension header are filtered only for presence using a bit 163193341Sjkim * vector with a flag for each header. 164193341Sjkim */ 165193341Sjkim#define EXT_FRAGMENT 0x1 166193341Sjkim#define EXT_HOPOPTS 0x2 167193341Sjkim#define EXT_ROUTING 0x4 168193341Sjkim#define EXT_AH 0x8 169193341Sjkim#define EXT_ESP 0x10 170284583Sjkim 171284583Sjkim/* 172284583Sjkim * Template for instructions. 173193267Sjkim * 174193267Sjkim * ipfw_insn is used for all instructions which require no operands, 175193267Sjkim * a single 16-bit value (arg1), or a couple of 8-bit values. 176 * 177 * For other instructions which require different/larger arguments 178 * we have derived structures, ipfw_insn_*. 179 * 180 * The size of the instruction (in 32-bit words) is in the low 181 * 6 bits of "len". The 2 remaining bits are used to implement 182 * NOT and OR on individual instructions. Given a type, you can 183 * compute the length to be put in "len" using F_INSN_SIZE(t) 184 * 185 * F_NOT negates the match result of the instruction. 186 * 187 * F_OR is used to build or blocks. By default, instructions 188 * are evaluated as part of a logical AND. An "or" block 189 * { X or Y or Z } contains F_OR set in all but the last 190 * instruction of the block. A match will cause the code 191 * to skip past the last instruction of the block. 192 * 193 * NOTA BENE: in a couple of places we assume that 194 * sizeof(ipfw_insn) == sizeof(u_int32_t) 195 * this needs to be fixed. 196 * 197 */ 198typedef struct _ipfw_insn { /* template for instructions */ 199 enum ipfw_opcodes opcode:8; 200 u_int8_t len; /* numer of 32-byte words */ 201#define F_NOT 0x80 202#define F_OR 0x40 203#define F_LEN_MASK 0x3f 204#define F_LEN(cmd) ((cmd)->len & F_LEN_MASK) 205 206 u_int16_t arg1; 207} ipfw_insn; 208 209/* 210 * The F_INSN_SIZE(type) computes the size, in 4-byte words, of 211 * a given type. 212 */ 213#define F_INSN_SIZE(t) ((sizeof (t))/sizeof(u_int32_t)) 214 215/* 216 * This is used to store an array of 16-bit entries (ports etc.) 217 */ 218typedef struct _ipfw_insn_u16 { 219 ipfw_insn o; 220 u_int16_t ports[2]; /* there may be more */ 221} ipfw_insn_u16; 222 223/* 224 * This is used to store an array of 32-bit entries 225 * (uid, single IPv4 addresses etc.) 226 */ 227typedef struct _ipfw_insn_u32 { 228 ipfw_insn o; 229 u_int32_t d[1]; /* one or more */ 230} ipfw_insn_u32; 231 232/* 233 * This is used to store IP addr-mask pairs. 234 */ 235typedef struct _ipfw_insn_ip { 236 ipfw_insn o; 237 struct in_addr addr; 238 struct in_addr mask; 239} ipfw_insn_ip; 240 241/* 242 * This is used to forward to a given address (ip). 243 */ 244typedef struct _ipfw_insn_sa { 245 ipfw_insn o; 246 struct sockaddr_in sa; 247} ipfw_insn_sa; 248 249/* 250 * This is used for MAC addr-mask pairs. 251 */ 252typedef struct _ipfw_insn_mac { 253 ipfw_insn o; 254 u_char addr[12]; /* dst[6] + src[6] */ 255 u_char mask[12]; /* dst[6] + src[6] */ 256} ipfw_insn_mac; 257 258/* 259 * This is used for interface match rules (recv xx, xmit xx). 260 */ 261typedef struct _ipfw_insn_if { 262 ipfw_insn o; 263 union { 264 struct in_addr ip; 265 int glob; 266 } p; 267 char name[IFNAMSIZ]; 268} ipfw_insn_if; 269 270/* 271 * This is used for pipe and queue actions, which need to store 272 * a single pointer (which can have different size on different 273 * architectures. 274 * Note that, because of previous instructions, pipe_ptr might 275 * be unaligned in the overall structure, so it needs to be 276 * manipulated with care. 277 */ 278typedef struct _ipfw_insn_pipe { 279 ipfw_insn o; 280 void *pipe_ptr; /* XXX */ 281} ipfw_insn_pipe; 282 283/* 284 * This is used for storing an altq queue id number. 285 */ 286typedef struct _ipfw_insn_altq { 287 ipfw_insn o; 288 u_int32_t qid; 289} ipfw_insn_altq; 290 291/* 292 * This is used for limit rules. 293 */ 294typedef struct _ipfw_insn_limit { 295 ipfw_insn o; 296 u_int8_t _pad; 297 u_int8_t limit_mask; /* combination of DYN_* below */ 298#define DYN_SRC_ADDR 0x1 299#define DYN_SRC_PORT 0x2 300#define DYN_DST_ADDR 0x4 301#define DYN_DST_PORT 0x8 302 303 u_int16_t conn_limit; 304} ipfw_insn_limit; 305 306/* 307 * This is used for log instructions. 308 */ 309typedef struct _ipfw_insn_log { 310 ipfw_insn o; 311 u_int32_t max_log; /* how many do we log -- 0 = all */ 312 u_int32_t log_left; /* how many left to log */ 313} ipfw_insn_log; 314 315/* Apply ipv6 mask on ipv6 addr */ 316#define APPLY_MASK(addr,mask) \ 317 (addr)->__u6_addr.__u6_addr32[0] &= (mask)->__u6_addr.__u6_addr32[0]; \ 318 (addr)->__u6_addr.__u6_addr32[1] &= (mask)->__u6_addr.__u6_addr32[1]; \ 319 (addr)->__u6_addr.__u6_addr32[2] &= (mask)->__u6_addr.__u6_addr32[2]; \ 320 (addr)->__u6_addr.__u6_addr32[3] &= (mask)->__u6_addr.__u6_addr32[3]; 321 322/* Structure for ipv6 */ 323typedef struct _ipfw_insn_ip6 { 324 ipfw_insn o; 325 struct in6_addr addr6; 326 struct in6_addr mask6; 327} ipfw_insn_ip6; 328 329/* Used to support icmp6 types */ 330typedef struct _ipfw_insn_icmp6 { 331 ipfw_insn o; 332 uint32_t d[7]; /* XXX This number si related to the netinet/icmp6.h 333 * define ICMP6_MAXTYPE 334 * as follows: n = ICMP6_MAXTYPE/32 + 1 335 * Actually is 203 336 */ 337} ipfw_insn_icmp6; 338 339/* 340 * Here we have the structure representing an ipfw rule. 341 * 342 * It starts with a general area (with link fields and counters) 343 * followed by an array of one or more instructions, which the code 344 * accesses as an array of 32-bit values. 345 * 346 * Given a rule pointer r: 347 * 348 * r->cmd is the start of the first instruction. 349 * ACTION_PTR(r) is the start of the first action (things to do 350 * once a rule matched). 351 * 352 * When assembling instruction, remember the following: 353 * 354 * + if a rule has a "keep-state" (or "limit") option, then the 355 * first instruction (at r->cmd) MUST BE an O_PROBE_STATE 356 * + if a rule has a "log" option, then the first action 357 * (at ACTION_PTR(r)) MUST be O_LOG 358 * + if a rule has an "altq" option, it comes after "log" 359 * 360 * NOTE: we use a simple linked list of rules because we never need 361 * to delete a rule without scanning the list. We do not use 362 * queue(3) macros for portability and readability. 363 */ 364 365struct ip_fw { 366 struct ip_fw *next; /* linked list of rules */ 367 struct ip_fw *next_rule; /* ptr to next [skipto] rule */ 368 /* 'next_rule' is used to pass up 'set_disable' status */ 369 370 u_int16_t act_ofs; /* offset of action in 32-bit units */ 371 u_int16_t cmd_len; /* # of 32-bit words in cmd */ 372 u_int16_t rulenum; /* rule number */ 373 u_int8_t set; /* rule set (0..31) */ 374#define RESVD_SET 31 /* set for default and persistent rules */ 375 u_int8_t _pad; /* padding */ 376 377 /* These fields are present in all rules. */ 378 u_int64_t pcnt; /* Packet counter */ 379 u_int64_t bcnt; /* Byte counter */ 380 u_int32_t timestamp; /* tv_sec of last match */ 381 382 ipfw_insn cmd[1]; /* storage for commands */ 383}; 384 385#define ACTION_PTR(rule) \ 386 (ipfw_insn *)( (u_int32_t *)((rule)->cmd) + ((rule)->act_ofs) ) 387 388#define RULESIZE(rule) (sizeof(struct ip_fw) + \ 389 ((struct ip_fw *)(rule))->cmd_len * 4 - 4) 390 391/* 392 * This structure is used as a flow mask and a flow id for various 393 * parts of the code. 394 */ 395struct ipfw_flow_id { 396 u_int32_t dst_ip; 397 u_int32_t src_ip; 398 u_int16_t dst_port; 399 u_int16_t src_port; 400 u_int8_t proto; 401 u_int8_t flags; /* protocol-specific flags */ 402 uint8_t addr_type; /* 4 = ipv4, 6 = ipv6, 1=ether ? */ 403 struct in6_addr dst_ip6; /* could also store MAC addr! */ 404 struct in6_addr src_ip6; 405 u_int32_t flow_id6; 406}; 407 408#define IS_IP6_FLOW_ID(id) ((id)->addr_type == 6) 409 410/* 411 * Dynamic ipfw rule. 412 */ 413typedef struct _ipfw_dyn_rule ipfw_dyn_rule; 414 415struct _ipfw_dyn_rule { 416 ipfw_dyn_rule *next; /* linked list of rules. */ 417 struct ip_fw *rule; /* pointer to rule */ 418 /* 'rule' is used to pass up the rule number (from the parent) */ 419 420 ipfw_dyn_rule *parent; /* pointer to parent rule */ 421 u_int64_t pcnt; /* packet match counter */ 422 u_int64_t bcnt; /* byte match counter */ 423 struct ipfw_flow_id id; /* (masked) flow id */ 424 u_int32_t expire; /* expire time */ 425 u_int32_t bucket; /* which bucket in hash table */ 426 u_int32_t state; /* state of this rule (typically a 427 * combination of TCP flags) 428 */ 429 u_int32_t ack_fwd; /* most recent ACKs in forward */ 430 u_int32_t ack_rev; /* and reverse directions (used */ 431 /* to generate keepalives) */ 432 u_int16_t dyn_type; /* rule type */ 433 u_int16_t count; /* refcount */ 434}; 435 436/* 437 * Definitions for IP option names. 438 */ 439#define IP_FW_IPOPT_LSRR 0x01 440#define IP_FW_IPOPT_SSRR 0x02 441#define IP_FW_IPOPT_RR 0x04 442#define IP_FW_IPOPT_TS 0x08 443 444/* 445 * Definitions for TCP option names. 446 */ 447#define IP_FW_TCPOPT_MSS 0x01 448#define IP_FW_TCPOPT_WINDOW 0x02 449#define IP_FW_TCPOPT_SACK 0x04 450#define IP_FW_TCPOPT_TS 0x08 451#define IP_FW_TCPOPT_CC 0x10 452 453#define ICMP_REJECT_RST 0x100 /* fake ICMP code (send a TCP RST) */ 454 455/* 456 * These are used for lookup tables. 457 */ 458typedef struct _ipfw_table_entry { 459 in_addr_t addr; /* network address */ 460 u_int32_t value; /* value */ 461 u_int16_t tbl; /* table number */ 462 u_int8_t masklen; /* mask length */ 463} ipfw_table_entry; 464 465typedef struct _ipfw_table { 466 u_int32_t size; /* size of entries in bytes */ 467 u_int32_t cnt; /* # of entries */ 468 u_int16_t tbl; /* table number */ 469 ipfw_table_entry ent[0]; /* entries */ 470} ipfw_table; 471 472/* 473 * Main firewall chains definitions and global var's definitions. 474 */ 475#ifdef _KERNEL 476 477/* Return values from ipfw_chk() */ 478enum { 479 IP_FW_PASS = 0, 480 IP_FW_DENY, 481 IP_FW_DIVERT, 482 IP_FW_TEE, 483 IP_FW_DUMMYNET, 484 IP_FW_NETGRAPH, 485 IP_FW_NGTEE, 486}; 487 488/* flags for divert mtag */ 489#define IP_FW_DIVERT_LOOPBACK_FLAG 0x00080000 490#define IP_FW_DIVERT_OUTPUT_FLAG 0x00100000 491 492/* 493 * Structure for collecting parameters to dummynet for ip6_output forwarding 494 */ 495struct _ip6dn_args { 496 struct ip6_pktopts *opt_or; 497 struct route_in6 ro_or; 498 int flags_or; 499 struct ip6_moptions *im6o_or; 500 struct ifnet *origifp_or; 501 struct ifnet *ifp_or; 502 struct sockaddr_in6 dst_or; 503 u_long mtu_or; 504 struct route_in6 ro_pmtu_or; 505}; 506 507/* 508 * Arguments for calling ipfw_chk() and dummynet_io(). We put them 509 * all into a structure because this way it is easier and more 510 * efficient to pass variables around and extend the interface. 511 */ 512struct ip_fw_args { 513 struct mbuf *m; /* the mbuf chain */ 514 struct ifnet *oif; /* output interface */ 515 struct sockaddr_in *next_hop; /* forward address */ 516 struct ip_fw *rule; /* matching rule */ 517 struct ether_header *eh; /* for bridged packets */ 518 519 int flags; /* for dummynet */ 520 521 struct ipfw_flow_id f_id; /* grabbed from IP header */ 522 u_int32_t cookie; /* a cookie depending on rule action */ 523 struct inpcb *inp; 524 525 struct _ip6dn_args dummypar; /* dummynet->ip6_output */ 526}; 527 528/* 529 * Function definitions. 530 */ 531 532/* Firewall hooks */ 533struct sockopt; 534struct dn_flow_set; 535 536int ipfw_check_in(void *, struct mbuf **, struct ifnet *, int, struct inpcb *inp); 537int ipfw_check_out(void *, struct mbuf **, struct ifnet *, int, struct inpcb *inp); 538 539int ipfw_chk(struct ip_fw_args *); 540 541int ipfw_init(void); 542void ipfw_destroy(void); 543 544void flush_pipe_ptrs(struct dn_flow_set *match); /* used by dummynet */ 545 546typedef int ip_fw_ctl_t(struct sockopt *); 547extern ip_fw_ctl_t *ip_fw_ctl_ptr; 548extern int fw_one_pass; 549extern int fw_enable; 550 551/* For kernel ipfw_ether and ipfw_bridge. */ 552typedef int ip_fw_chk_t(struct ip_fw_args *args); 553extern ip_fw_chk_t *ip_fw_chk_ptr; 554#define IPFW_LOADED (ip_fw_chk_ptr != NULL) 555 556#endif /* _KERNEL */ 557#endif /* _IPFW2_H */ 558