1 /*- 2 * Copyright (c) 2002 Luigi Rizzo, Universita` di Pisa 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 * $FreeBSD$ 26 */ 27 28 #ifndef _IPFW2_H 29 #define _IPFW2_H 30 31 /* 32 * The kernel representation of ipfw rules is made of a list of 33 * 'instructions' (for all practical purposes equivalent to BPF 34 * instructions), which specify which fields of the packet 35 * (or its metadata) should be analysed. 36 * 37 * Each instruction is stored in a structure which begins with 38 * "ipfw_insn", and can contain extra fields depending on the 39 * instruction type (listed below). 40 * Note that the code is written so that individual instructions 41 * have a size which is a multiple of 32 bits. This means that, if 42 * such structures contain pointers or other 64-bit entities, 43 * (there is just one instance now) they may end up unaligned on 44 * 64-bit architectures, so the must be handled with care. 45 * 46 * "enum ipfw_opcodes" are the opcodes supported. We can have up 47 * to 256 different opcodes. When adding new opcodes, they should 48 * be appended to the end of the opcode list before O_LAST_OPCODE, 49 * this will prevent the ABI from being broken, otherwise users 50 * will have to recompile ipfw(8) when they update the kernel. 51 */ 52 53 enum ipfw_opcodes { /* arguments (4 byte each) */ 54 O_NOP, 55 56 O_IP_SRC, /* u32 = IP */ 57 O_IP_SRC_MASK, /* ip = IP/mask */ 58 O_IP_SRC_ME, /* none */ 59 O_IP_SRC_SET, /* u32=base, arg1=len, bitmap */ 60 61 O_IP_DST, /* u32 = IP */ 62 O_IP_DST_MASK, /* ip = IP/mask */ 63 O_IP_DST_ME, /* none */ 64 O_IP_DST_SET, /* u32=base, arg1=len, bitmap */ 65 66 O_IP_SRCPORT, /* (n)port list:mask 4 byte ea */ 67 O_IP_DSTPORT, /* (n)port list:mask 4 byte ea */ 68 O_PROTO, /* arg1=protocol */ 69 70 O_MACADDR2, /* 2 mac addr:mask */ 71 O_MAC_TYPE, /* same as srcport */ 72 73 O_LAYER2, /* none */ 74 O_IN, /* none */ 75 O_FRAG, /* none */ 76 77 O_RECV, /* none */ 78 O_XMIT, /* none */ 79 O_VIA, /* none */ 80 81 O_IPOPT, /* arg1 = 2*u8 bitmap */ 82 O_IPLEN, /* arg1 = len */ 83 O_IPID, /* arg1 = id */ 84 85 O_IPTOS, /* arg1 = id */ 86 O_IPPRECEDENCE, /* arg1 = precedence << 5 */ 87 O_IPTTL, /* arg1 = TTL */ 88 89 O_IPVER, /* arg1 = version */ 90 O_UID, /* u32 = id */ 91 O_GID, /* u32 = id */ 92 O_ESTAB, /* none (tcp established) */ 93 O_TCPFLAGS, /* arg1 = 2*u8 bitmap */ 94 O_TCPWIN, /* arg1 = desired win */ 95 O_TCPSEQ, /* u32 = desired seq. */ 96 O_TCPACK, /* u32 = desired seq. */ 97 O_ICMPTYPE, /* u32 = icmp bitmap */ 98 O_TCPOPTS, /* arg1 = 2*u8 bitmap */ 99 100 O_VERREVPATH, /* none */ 101 O_VERSRCREACH, /* none */ 102 103 O_PROBE_STATE, /* none */ 104 O_KEEP_STATE, /* none */ 105 O_LIMIT, /* ipfw_insn_limit */ 106 O_LIMIT_PARENT, /* dyn_type, not an opcode. */ 107 108 /* 109 * These are really 'actions'. 110 */ 111 112 O_LOG, /* ipfw_insn_log */ 113 O_PROB, /* u32 = match probability */ 114 115 O_CHECK_STATE, /* none */ 116 O_ACCEPT, /* none */ 117 O_DENY, /* none */ 118 O_REJECT, /* arg1=icmp arg (same as deny) */ 119 O_COUNT, /* none */ 120 O_SKIPTO, /* arg1=next rule number */ 121 O_PIPE, /* arg1=pipe number */ 122 O_QUEUE, /* arg1=queue number */ 123 O_DIVERT, /* arg1=port number */ 124 O_TEE, /* arg1=port number */ 125 O_FORWARD_IP, /* fwd sockaddr */ 126 O_FORWARD_MAC, /* fwd mac */ 127 O_NAT, /* nope */ 128 129 /* 130 * More opcodes. 131 */ 132 O_IPSEC, /* has ipsec history */ 133 O_IP_SRC_LOOKUP, /* arg1=table number, u32=value */ 134 O_IP_DST_LOOKUP, /* arg1=table number, u32=value */ 135 O_ANTISPOOF, /* none */ 136 O_JAIL, /* u32 = id */ 137 O_ALTQ, /* u32 = altq classif. qid */ 138 O_DIVERTED, /* arg1=bitmap (1:loop, 2:out) */ 139 O_TCPDATALEN, /* arg1 = tcp data len */ 140 O_IP6_SRC, /* address without mask */ 141 O_IP6_SRC_ME, /* my addresses */ 142 O_IP6_SRC_MASK, /* address with the mask */ 143 O_IP6_DST, 144 O_IP6_DST_ME, 145 O_IP6_DST_MASK, 146 O_FLOW6ID, /* for flow id tag in the ipv6 pkt */ 147 O_ICMP6TYPE, /* icmp6 packet type filtering */ 148 O_EXT_HDR, /* filtering for ipv6 extension header */ 149 O_IP6, 150 151 /* 152 * actions for ng_ipfw 153 */ 154 O_NETGRAPH, /* send to ng_ipfw */ 155 O_NGTEE, /* copy to ng_ipfw */ 156 157 O_IP4, 158 159 O_UNREACH6, /* arg1=icmpv6 code arg (deny) */ 160 161 O_TAG, /* arg1=tag number */ 162 O_TAGGED, /* arg1=tag number */ 163 164 O_LAST_OPCODE /* not an opcode! */ 165 }; 166 167 /* 168 * The extension header are filtered only for presence using a bit 169 * vector with a flag for each header. 170 */ 171 #define EXT_FRAGMENT 0x1 172 #define EXT_HOPOPTS 0x2 173 #define EXT_ROUTING 0x4 174 #define EXT_AH 0x8 175 #define EXT_ESP 0x10 176 #define EXT_DSTOPTS 0x20 177 178 /* 179 * Template for instructions. 180 * 181 * ipfw_insn is used for all instructions which require no operands, 182 * a single 16-bit value (arg1), or a couple of 8-bit values. 183 * 184 * For other instructions which require different/larger arguments 185 * we have derived structures, ipfw_insn_*. 186 * 187 * The size of the instruction (in 32-bit words) is in the low 188 * 6 bits of "len". The 2 remaining bits are used to implement 189 * NOT and OR on individual instructions. Given a type, you can 190 * compute the length to be put in "len" using F_INSN_SIZE(t) 191 * 192 * F_NOT negates the match result of the instruction. 193 * 194 * F_OR is used to build or blocks. By default, instructions 195 * are evaluated as part of a logical AND. An "or" block 196 * { X or Y or Z } contains F_OR set in all but the last 197 * instruction of the block. A match will cause the code 198 * to skip past the last instruction of the block. 199 * 200 * NOTA BENE: in a couple of places we assume that 201 * sizeof(ipfw_insn) == sizeof(u_int32_t) 202 * this needs to be fixed. 203 * 204 */ 205 typedef struct _ipfw_insn { /* template for instructions */ 206 enum ipfw_opcodes opcode:8; 207 u_int8_t len; /* numer of 32-byte words */ 208 #define F_NOT 0x80 209 #define F_OR 0x40 210 #define F_LEN_MASK 0x3f 211 #define F_LEN(cmd) ((cmd)->len & F_LEN_MASK) 212 213 u_int16_t arg1; 214 } ipfw_insn; 215 216 /* 217 * The F_INSN_SIZE(type) computes the size, in 4-byte words, of 218 * a given type. 219 */ 220 #define F_INSN_SIZE(t) ((sizeof (t))/sizeof(u_int32_t)) 221 222 #define MTAG_IPFW 1148380143 /* IPFW-tagged cookie */ 223 224 /* 225 * This is used to store an array of 16-bit entries (ports etc.) 226 */ 227 typedef struct _ipfw_insn_u16 { 228 ipfw_insn o; 229 u_int16_t ports[2]; /* there may be more */ 230 } ipfw_insn_u16; 231 232 /* 233 * This is used to store an array of 32-bit entries 234 * (uid, single IPv4 addresses etc.) 235 */ 236 typedef struct _ipfw_insn_u32 { 237 ipfw_insn o; 238 u_int32_t d[1]; /* one or more */ 239 } ipfw_insn_u32; 240 241 /* 242 * This is used to store IP addr-mask pairs. 243 */ 244 typedef struct _ipfw_insn_ip { 245 ipfw_insn o; 246 struct in_addr addr; 247 struct in_addr mask; 248 } ipfw_insn_ip; 249 250 /* 251 * This is used to forward to a given address (ip). 252 */ 253 typedef struct _ipfw_insn_sa { 254 ipfw_insn o; 255 struct sockaddr_in sa; 256 } ipfw_insn_sa; 257 258 /* 259 * This is used for MAC addr-mask pairs. 260 */ 261 typedef struct _ipfw_insn_mac { 262 ipfw_insn o; 263 u_char addr[12]; /* dst[6] + src[6] */ 264 u_char mask[12]; /* dst[6] + src[6] */ 265 } ipfw_insn_mac; 266 267 /* 268 * This is used for interface match rules (recv xx, xmit xx). 269 */ 270 typedef struct _ipfw_insn_if { 271 ipfw_insn o; 272 union { 273 struct in_addr ip; 274 int glob; 275 } p; 276 char name[IFNAMSIZ]; 277 } ipfw_insn_if; 278 279 /* 280 * This is used for storing an altq queue id number. 281 */ 282 typedef struct _ipfw_insn_altq { 283 ipfw_insn o; 284 u_int32_t qid; 285 } ipfw_insn_altq; 286 287 /* 288 * This is used for limit rules. 289 */ 290 typedef struct _ipfw_insn_limit { 291 ipfw_insn o; 292 u_int8_t _pad; 293 u_int8_t limit_mask; /* combination of DYN_* below */ 294 #define DYN_SRC_ADDR 0x1 295 #define DYN_SRC_PORT 0x2 296 #define DYN_DST_ADDR 0x4 297 #define DYN_DST_PORT 0x8 298 299 u_int16_t conn_limit; 300 } ipfw_insn_limit; 301 302 /* 303 * This is used for log instructions. 304 */ 305 typedef struct _ipfw_insn_log { 306 ipfw_insn o; 307 u_int32_t max_log; /* how many do we log -- 0 = all */ 308 u_int32_t log_left; /* how many left to log */ 309 } ipfw_insn_log; 310 311 /* Server pool support (LSNAT). */ 312 struct cfg_spool { 313 LIST_ENTRY(cfg_spool) _next; /* chain of spool instances */ 314 struct in_addr addr; 315 u_short port; 316 }; 317 318 /* Redirect modes id. */ 319 #define REDIR_ADDR 0x01 320 #define REDIR_PORT 0x02 321 #define REDIR_PROTO 0x04 322 323 /* Nat redirect configuration. */ 324 struct cfg_redir { 325 LIST_ENTRY(cfg_redir) _next; /* chain of redir instances */ 326 u_int16_t mode; /* type of redirect mode */ 327 struct in_addr laddr; /* local ip address */ 328 struct in_addr paddr; /* public ip address */ 329 struct in_addr raddr; /* remote ip address */ 330 u_short lport; /* local port */ 331 u_short pport; /* public port */ 332 u_short rport; /* remote port */ 333 u_short pport_cnt; /* number of public ports */ 334 u_short rport_cnt; /* number of remote ports */ 335 int proto; /* protocol: tcp/udp */ 336 struct alias_link **alink; 337 /* num of entry in spool chain */ 338 u_int16_t spool_cnt; 339 /* chain of spool instances */ 340 LIST_HEAD(spool_chain, cfg_spool) spool_chain; 341 }; 342 343 #define NAT_BUF_LEN 1024 344 /* Nat configuration data struct. */ 345 struct cfg_nat { 346 /* chain of nat instances */ 347 LIST_ENTRY(cfg_nat) _next; 348 int id; /* nat id */ 349 struct in_addr ip; /* nat ip address */ 350 char if_name[IF_NAMESIZE]; /* interface name */ 351 int mode; /* aliasing mode */ 352 struct libalias *lib; /* libalias instance */ 353 /* number of entry in spool chain */ 354 int redir_cnt; 355 /* chain of redir instances */ 356 LIST_HEAD(redir_chain, cfg_redir) redir_chain; 357 }; 358 359 #define SOF_NAT sizeof(struct cfg_nat) 360 #define SOF_REDIR sizeof(struct cfg_redir) 361 #define SOF_SPOOL sizeof(struct cfg_spool) 362 363 /* Nat command. */ 364 typedef struct _ipfw_insn_nat { 365 ipfw_insn o; 366 struct cfg_nat *nat; 367 } ipfw_insn_nat; 368 369 /* Apply ipv6 mask on ipv6 addr */ 370 #define APPLY_MASK(addr,mask) \ 371 (addr)->__u6_addr.__u6_addr32[0] &= (mask)->__u6_addr.__u6_addr32[0]; \ 372 (addr)->__u6_addr.__u6_addr32[1] &= (mask)->__u6_addr.__u6_addr32[1]; \ 373 (addr)->__u6_addr.__u6_addr32[2] &= (mask)->__u6_addr.__u6_addr32[2]; \ 374 (addr)->__u6_addr.__u6_addr32[3] &= (mask)->__u6_addr.__u6_addr32[3]; 375 376 /* Structure for ipv6 */ 377 typedef struct _ipfw_insn_ip6 { 378 ipfw_insn o; 379 struct in6_addr addr6; 380 struct in6_addr mask6; 381 } ipfw_insn_ip6; 382 383 /* Used to support icmp6 types */ 384 typedef struct _ipfw_insn_icmp6 { 385 ipfw_insn o; 386 uint32_t d[7]; /* XXX This number si related to the netinet/icmp6.h 387 * define ICMP6_MAXTYPE 388 * as follows: n = ICMP6_MAXTYPE/32 + 1 389 * Actually is 203 390 */ 391 } ipfw_insn_icmp6; 392 393 /* 394 * Here we have the structure representing an ipfw rule. 395 * 396 * It starts with a general area (with link fields and counters) 397 * followed by an array of one or more instructions, which the code 398 * accesses as an array of 32-bit values. 399 * 400 * Given a rule pointer r: 401 * 402 * r->cmd is the start of the first instruction. 403 * ACTION_PTR(r) is the start of the first action (things to do 404 * once a rule matched). 405 * 406 * When assembling instruction, remember the following: 407 * 408 * + if a rule has a "keep-state" (or "limit") option, then the 409 * first instruction (at r->cmd) MUST BE an O_PROBE_STATE 410 * + if a rule has a "log" option, then the first action 411 * (at ACTION_PTR(r)) MUST be O_LOG 412 * + if a rule has an "altq" option, it comes after "log" 413 * + if a rule has an O_TAG option, it comes after "log" and "altq" 414 * 415 * NOTE: we use a simple linked list of rules because we never need 416 * to delete a rule without scanning the list. We do not use 417 * queue(3) macros for portability and readability. 418 */ 419 420 struct ip_fw { 421 struct ip_fw *next; /* linked list of rules */ 422 struct ip_fw *next_rule; /* ptr to next [skipto] rule */ 423 /* 'next_rule' is used to pass up 'set_disable' status */ 424 425 u_int16_t act_ofs; /* offset of action in 32-bit units */ 426 u_int16_t cmd_len; /* # of 32-bit words in cmd */ 427 u_int16_t rulenum; /* rule number */ 428 u_int8_t set; /* rule set (0..31) */ 429 #define RESVD_SET 31 /* set for default and persistent rules */ 430 u_int8_t _pad; /* padding */ 431 432 /* These fields are present in all rules. */ 433 u_int64_t pcnt; /* Packet counter */ 434 u_int64_t bcnt; /* Byte counter */ 435 u_int32_t timestamp; /* tv_sec of last match */ 436 437 ipfw_insn cmd[1]; /* storage for commands */ 438 }; 439 440 #define ACTION_PTR(rule) \ 441 (ipfw_insn *)( (u_int32_t *)((rule)->cmd) + ((rule)->act_ofs) ) 442 443 #define RULESIZE(rule) (sizeof(struct ip_fw) + \ 444 ((struct ip_fw *)(rule))->cmd_len * 4 - 4) 445 446 /* 447 * This structure is used as a flow mask and a flow id for various 448 * parts of the code. 449 */ 450 struct ipfw_flow_id { 451 u_int32_t dst_ip; 452 u_int32_t src_ip; 453 u_int16_t dst_port; 454 u_int16_t src_port; 455 u_int8_t proto; 456 u_int8_t flags; /* protocol-specific flags */ 457 uint8_t addr_type; /* 4 = ipv4, 6 = ipv6, 1=ether ? */ 458 struct in6_addr dst_ip6; /* could also store MAC addr! */ 459 struct in6_addr src_ip6; 460 u_int32_t flow_id6; 461 u_int32_t frag_id6; 462 }; 463 464 #define IS_IP6_FLOW_ID(id) ((id)->addr_type == 6) 465 466 /* 467 * Dynamic ipfw rule. 468 */ 469 typedef struct _ipfw_dyn_rule ipfw_dyn_rule; 470 471 struct _ipfw_dyn_rule { 472 ipfw_dyn_rule *next; /* linked list of rules. */ 473 struct ip_fw *rule; /* pointer to rule */ 474 /* 'rule' is used to pass up the rule number (from the parent) */ 475 476 ipfw_dyn_rule *parent; /* pointer to parent rule */ 477 u_int64_t pcnt; /* packet match counter */ 478 u_int64_t bcnt; /* byte match counter */ 479 struct ipfw_flow_id id; /* (masked) flow id */ 480 u_int32_t expire; /* expire time */ 481 u_int32_t bucket; /* which bucket in hash table */ 482 u_int32_t state; /* state of this rule (typically a 483 * combination of TCP flags) 484 */ 485 u_int32_t ack_fwd; /* most recent ACKs in forward */ 486 u_int32_t ack_rev; /* and reverse directions (used */ 487 /* to generate keepalives) */ 488 u_int16_t dyn_type; /* rule type */ 489 u_int16_t count; /* refcount */ 490 }; 491 492 /* 493 * Definitions for IP option names. 494 */ 495 #define IP_FW_IPOPT_LSRR 0x01 496 #define IP_FW_IPOPT_SSRR 0x02 497 #define IP_FW_IPOPT_RR 0x04 498 #define IP_FW_IPOPT_TS 0x08 499 500 /* 501 * Definitions for TCP option names. 502 */ 503 #define IP_FW_TCPOPT_MSS 0x01 504 #define IP_FW_TCPOPT_WINDOW 0x02 505 #define IP_FW_TCPOPT_SACK 0x04 506 #define IP_FW_TCPOPT_TS 0x08 507 #define IP_FW_TCPOPT_CC 0x10 508 509 #define ICMP_REJECT_RST 0x100 /* fake ICMP code (send a TCP RST) */ 510 #define ICMP6_UNREACH_RST 0x100 /* fake ICMPv6 code (send a TCP RST) */ 511 512 /* 513 * These are used for lookup tables. 514 */ 515 typedef struct _ipfw_table_entry { 516 in_addr_t addr; /* network address */ 517 u_int32_t value; /* value */ 518 u_int16_t tbl; /* table number */ 519 u_int8_t masklen; /* mask length */ 520 } ipfw_table_entry; 521 522 typedef struct _ipfw_table { 523 u_int32_t size; /* size of entries in bytes */ 524 u_int32_t cnt; /* # of entries */ 525 u_int16_t tbl; /* table number */ 526 ipfw_table_entry ent[0]; /* entries */ 527 } ipfw_table; 528 529 #define IP_FW_TABLEARG 65535 530 531 /* 532 * Main firewall chains definitions and global var's definitions. 533 */ 534 #ifdef _KERNEL 535 536 /* Return values from ipfw_chk() */ 537 enum { 538 IP_FW_PASS = 0, 539 IP_FW_DENY, 540 IP_FW_DIVERT, 541 IP_FW_TEE, 542 IP_FW_DUMMYNET, 543 IP_FW_NETGRAPH, 544 IP_FW_NGTEE, 545 IP_FW_NAT, 546 }; 547 548 /* flags for divert mtag */ 549 #define IP_FW_DIVERT_LOOPBACK_FLAG 0x00080000 550 #define IP_FW_DIVERT_OUTPUT_FLAG 0x00100000 551 552 /* 553 * Structure for collecting parameters to dummynet for ip6_output forwarding 554 */ 555 struct _ip6dn_args { 556 struct ip6_pktopts *opt_or; 557 struct route_in6 ro_or; 558 int flags_or; 559 struct ip6_moptions *im6o_or; 560 struct ifnet *origifp_or; 561 struct ifnet *ifp_or; 562 struct sockaddr_in6 dst_or; 563 u_long mtu_or; 564 struct route_in6 ro_pmtu_or; 565 }; 566 567 /* 568 * Arguments for calling ipfw_chk() and dummynet_io(). We put them 569 * all into a structure because this way it is easier and more 570 * efficient to pass variables around and extend the interface. 571 */ 572 struct ip_fw_args { 573 struct mbuf *m; /* the mbuf chain */ 574 struct ifnet *oif; /* output interface */ 575 struct sockaddr_in *next_hop; /* forward address */ 576 struct ip_fw *rule; /* matching rule */ 577 struct ether_header *eh; /* for bridged packets */ 578 579 struct ipfw_flow_id f_id; /* grabbed from IP header */ 580 u_int32_t cookie; /* a cookie depending on rule action */ 581 struct inpcb *inp; 582 583 struct _ip6dn_args dummypar; /* dummynet->ip6_output */ 584 struct sockaddr_in hopstore; /* store here if cannot use a pointer */ 585 }; 586 587 /* 588 * Function definitions. 589 */ 590 591 /* Firewall hooks */ 592 struct sockopt; 593 struct dn_flow_set; 594 595 int ipfw_check_in(void *, struct mbuf **, struct ifnet *, int, struct inpcb *inp); 596 int ipfw_check_out(void *, struct mbuf **, struct ifnet *, int, struct inpcb *inp); 597 598 int ipfw_chk(struct ip_fw_args *); 599 600 int ipfw_init(void); 601 void ipfw_destroy(void); 602 603 typedef int ip_fw_ctl_t(struct sockopt *); 604 extern ip_fw_ctl_t *ip_fw_ctl_ptr; 605 extern int fw_one_pass; 606 extern int fw_enable; 607 #ifdef INET6 608 extern int fw6_enable; 609 #endif 610 611 /* For kernel ipfw_ether and ipfw_bridge. */ 612 typedef int ip_fw_chk_t(struct ip_fw_args *args); 613 extern ip_fw_chk_t *ip_fw_chk_ptr; 614 #define IPFW_LOADED (ip_fw_chk_ptr != NULL) 615 616 #endif /* _KERNEL */ 617 #endif /* _IPFW2_H */ 618