aboutsummaryrefslogtreecommitdiff
path: root/sys/netinet/ip_fw.h
blob: 18920a0242cb4c8f7ff1b2b418a6c1052d7d2f0e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
/*-
 * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */

#ifndef _IPFW2_H
#define _IPFW2_H

/*
 * The default rule number.  By the design of ip_fw, the default rule
 * is the last one, so its number can also serve as the highest number
 * allowed for a rule.  The ip_fw code relies on both meanings of this
 * constant. 
 */
#define	IPFW_DEFAULT_RULE	65535

/*
 * The number of ipfw tables.  The maximum allowed table number is the
 * (IPFW_TABLES_MAX - 1).
 */
#define	IPFW_TABLES_MAX		128

/*
 * Most commands (queue, pipe, tag, untag, limit...) can have a 16-bit
 * argument between 1 and 65534. The value 0 is unused, the value
 * 65535 (IP_FW_TABLEARG) is used to represent 'tablearg', i.e. the
 * can be 1..65534, or 65535 to indicate the use of a 'tablearg'
 * result of the most recent table() lookup.
 * Note that 16bit is only a historical limit, resulting from
 * the use of a 16-bit fields for that value. In reality, we can have
 * 2^32 pipes, queues, tag values and so on, and use 0 as a tablearg.
 */
#define	IPFW_ARG_MIN		1
#define	IPFW_ARG_MAX		65534
#define IP_FW_TABLEARG		65535	/* XXX should use 0 */

/*
 * The kernel representation of ipfw rules is made of a list of
 * 'instructions' (for all practical purposes equivalent to BPF
 * instructions), which specify which fields of the packet
 * (or its metadata) should be analysed.
 *
 * Each instruction is stored in a structure which begins with
 * "ipfw_insn", and can contain extra fields depending on the
 * instruction type (listed below).
 * Note that the code is written so that individual instructions
 * have a size which is a multiple of 32 bits. This means that, if
 * such structures contain pointers or other 64-bit entities,
 * (there is just one instance now) they may end up unaligned on
 * 64-bit architectures, so the must be handled with care.
 *
 * "enum ipfw_opcodes" are the opcodes supported. We can have up
 * to 256 different opcodes. When adding new opcodes, they should
 * be appended to the end of the opcode list before O_LAST_OPCODE,
 * this will prevent the ABI from being broken, otherwise users
 * will have to recompile ipfw(8) when they update the kernel.
 */

enum ipfw_opcodes {		/* arguments (4 byte each)	*/
	O_NOP,

	O_IP_SRC,		/* u32 = IP			*/
	O_IP_SRC_MASK,		/* ip = IP/mask			*/
	O_IP_SRC_ME,		/* none				*/
	O_IP_SRC_SET,		/* u32=base, arg1=len, bitmap	*/

	O_IP_DST,		/* u32 = IP			*/
	O_IP_DST_MASK,		/* ip = IP/mask			*/
	O_IP_DST_ME,		/* none				*/
	O_IP_DST_SET,		/* u32=base, arg1=len, bitmap	*/

	O_IP_SRCPORT,		/* (n)port list:mask 4 byte ea	*/
	O_IP_DSTPORT,		/* (n)port list:mask 4 byte ea	*/
	O_PROTO,		/* arg1=protocol		*/

	O_MACADDR2,		/* 2 mac addr:mask		*/
	O_MAC_TYPE,		/* same as srcport		*/

	O_LAYER2,		/* none				*/
	O_IN,			/* none				*/
	O_FRAG,			/* none				*/

	O_RECV,			/* none				*/
	O_XMIT,			/* none				*/
	O_VIA,			/* none				*/

	O_IPOPT,		/* arg1 = 2*u8 bitmap		*/
	O_IPLEN,		/* arg1 = len			*/
	O_IPID,			/* arg1 = id			*/

	O_IPTOS,		/* arg1 = id			*/
	O_IPPRECEDENCE,		/* arg1 = precedence << 5	*/
	O_IPTTL,		/* arg1 = TTL			*/

	O_IPVER,		/* arg1 = version		*/
	O_UID,			/* u32 = id			*/
	O_GID,			/* u32 = id			*/
	O_ESTAB,		/* none (tcp established)	*/
	O_TCPFLAGS,		/* arg1 = 2*u8 bitmap		*/
	O_TCPWIN,		/* arg1 = desired win		*/
	O_TCPSEQ,		/* u32 = desired seq.		*/
	O_TCPACK,		/* u32 = desired seq.		*/
	O_ICMPTYPE,		/* u32 = icmp bitmap		*/
	O_TCPOPTS,		/* arg1 = 2*u8 bitmap		*/

	O_VERREVPATH,		/* none				*/
	O_VERSRCREACH,		/* none				*/

	O_PROBE_STATE,		/* none				*/
	O_KEEP_STATE,		/* none				*/
	O_LIMIT,		/* ipfw_insn_limit		*/
	O_LIMIT_PARENT,		/* dyn_type, not an opcode.	*/

	/*
	 * These are really 'actions'.
	 */

	O_LOG,			/* ipfw_insn_log		*/
	O_PROB,			/* u32 = match probability	*/

	O_CHECK_STATE,		/* none				*/
	O_ACCEPT,		/* none				*/
	O_DENY,			/* none 			*/
	O_REJECT,		/* arg1=icmp arg (same as deny)	*/
	O_COUNT,		/* none				*/
	O_SKIPTO,		/* arg1=next rule number	*/
	O_PIPE,			/* arg1=pipe number		*/
	O_QUEUE,		/* arg1=queue number		*/
	O_DIVERT,		/* arg1=port number		*/
	O_TEE,			/* arg1=port number		*/
	O_FORWARD_IP,		/* fwd sockaddr			*/
	O_FORWARD_MAC,		/* fwd mac			*/
	O_NAT,                  /* nope                         */
	O_REASS,                /* none                         */
	
	/*
	 * More opcodes.
	 */
	O_IPSEC,		/* has ipsec history 		*/
	O_IP_SRC_LOOKUP,	/* arg1=table number, u32=value	*/
	O_IP_DST_LOOKUP,	/* arg1=table number, u32=value	*/
	O_ANTISPOOF,		/* none				*/
	O_JAIL,			/* u32 = id			*/
	O_ALTQ,			/* u32 = altq classif. qid	*/
	O_DIVERTED,		/* arg1=bitmap (1:loop, 2:out)	*/
	O_TCPDATALEN,		/* arg1 = tcp data len		*/
	O_IP6_SRC,		/* address without mask		*/
	O_IP6_SRC_ME,		/* my addresses			*/
	O_IP6_SRC_MASK,		/* address with the mask	*/
	O_IP6_DST,
	O_IP6_DST_ME,
	O_IP6_DST_MASK,
	O_FLOW6ID,		/* for flow id tag in the ipv6 pkt */
	O_ICMP6TYPE,		/* icmp6 packet type filtering	*/
	O_EXT_HDR,		/* filtering for ipv6 extension header */
	O_IP6,

	/*
	 * actions for ng_ipfw
	 */
	O_NETGRAPH,		/* send to ng_ipfw		*/
	O_NGTEE,		/* copy to ng_ipfw		*/

	O_IP4,

	O_UNREACH6,		/* arg1=icmpv6 code arg (deny)  */

	O_TAG,   		/* arg1=tag number */
	O_TAGGED,		/* arg1=tag number */

	O_SETFIB,		/* arg1=FIB number */
	O_FIB,			/* arg1=FIB desired fib number */

	O_LAST_OPCODE		/* not an opcode!		*/
};

/*
 * The extension header are filtered only for presence using a bit
 * vector with a flag for each header.
 */
#define EXT_FRAGMENT	0x1
#define EXT_HOPOPTS	0x2
#define EXT_ROUTING	0x4
#define EXT_AH		0x8
#define EXT_ESP		0x10
#define EXT_DSTOPTS	0x20
#define EXT_RTHDR0		0x40
#define EXT_RTHDR2		0x80

/*
 * Template for instructions.
 *
 * ipfw_insn is used for all instructions which require no operands,
 * a single 16-bit value (arg1), or a couple of 8-bit values.
 *
 * For other instructions which require different/larger arguments
 * we have derived structures, ipfw_insn_*.
 *
 * The size of the instruction (in 32-bit words) is in the low
 * 6 bits of "len". The 2 remaining bits are used to implement
 * NOT and OR on individual instructions. Given a type, you can
 * compute the length to be put in "len" using F_INSN_SIZE(t)
 *
 * F_NOT	negates the match result of the instruction.
 *
 * F_OR		is used to build or blocks. By default, instructions
 *		are evaluated as part of a logical AND. An "or" block
 *		{ X or Y or Z } contains F_OR set in all but the last
 *		instruction of the block. A match will cause the code
 *		to skip past the last instruction of the block.
 *
 * NOTA BENE: in a couple of places we assume that
 *	sizeof(ipfw_insn) == sizeof(u_int32_t)
 * this needs to be fixed.
 *
 */
typedef struct	_ipfw_insn {	/* template for instructions */
	enum ipfw_opcodes	opcode:8;
	u_int8_t	len;	/* number of 32-bit words */
#define	F_NOT		0x80
#define	F_OR		0x40
#define	F_LEN_MASK	0x3f
#define	F_LEN(cmd)	((cmd)->len & F_LEN_MASK)

	u_int16_t	arg1;
} ipfw_insn;

/*
 * The F_INSN_SIZE(type) computes the size, in 4-byte words, of
 * a given type.
 */
#define	F_INSN_SIZE(t)	((sizeof (t))/sizeof(u_int32_t))

/*
 * This is used to store an array of 16-bit entries (ports etc.)
 */
typedef struct	_ipfw_insn_u16 {
	ipfw_insn o;
	u_int16_t ports[2];	/* there may be more */
} ipfw_insn_u16;

/*
 * This is used to store an array of 32-bit entries
 * (uid, single IPv4 addresses etc.)
 */
typedef struct	_ipfw_insn_u32 {
	ipfw_insn o;
	u_int32_t d[1];	/* one or more */
} ipfw_insn_u32;

/*
 * This is used to store IP addr-mask pairs.
 */
typedef struct	_ipfw_insn_ip {
	ipfw_insn o;
	struct in_addr	addr;
	struct in_addr	mask;
} ipfw_insn_ip;

/*
 * This is used to forward to a given address (ip).
 */
typedef struct  _ipfw_insn_sa {
	ipfw_insn o;
	struct sockaddr_in sa;
} ipfw_insn_sa;

/*
 * This is used for MAC addr-mask pairs.
 */
typedef struct	_ipfw_insn_mac {
	ipfw_insn o;
	u_char addr[12];	/* dst[6] + src[6] */
	u_char mask[12];	/* dst[6] + src[6] */
} ipfw_insn_mac;

/*
 * This is used for interface match rules (recv xx, xmit xx).
 */
typedef struct	_ipfw_insn_if {
	ipfw_insn o;
	union {
		struct in_addr ip;
		int glob;
	} p;
	char name[IFNAMSIZ];
} ipfw_insn_if;

/*
 * This is used for storing an altq queue id number.
 */
typedef struct _ipfw_insn_altq {
	ipfw_insn	o;
	u_int32_t	qid;
} ipfw_insn_altq;

/*
 * This is used for limit rules.
 */
typedef struct	_ipfw_insn_limit {
	ipfw_insn o;
	u_int8_t _pad;
	u_int8_t limit_mask;	/* combination of DYN_* below	*/
#define	DYN_SRC_ADDR	0x1
#define	DYN_SRC_PORT	0x2
#define	DYN_DST_ADDR	0x4
#define	DYN_DST_PORT	0x8

	u_int16_t conn_limit;
} ipfw_insn_limit;

/*
 * This is used for log instructions.
 */
typedef struct  _ipfw_insn_log {
        ipfw_insn o;
	u_int32_t max_log;	/* how many do we log -- 0 = all */
	u_int32_t log_left;	/* how many left to log 	*/
} ipfw_insn_log;

/*
 * Data structures required by both ipfw(8) and ipfw(4) but not part of the
 * management API are protected by IPFW_INTERNAL.
 */
#ifdef IPFW_INTERNAL
/* Server pool support (LSNAT). */
struct cfg_spool {
	LIST_ENTRY(cfg_spool)   _next;          /* chain of spool instances */
	struct in_addr          addr;
	u_short                 port;
};
#endif

/* Redirect modes id. */
#define REDIR_ADDR      0x01
#define REDIR_PORT      0x02
#define REDIR_PROTO     0x04

#ifdef IPFW_INTERNAL
/* Nat redirect configuration. */
struct cfg_redir {
	LIST_ENTRY(cfg_redir)   _next;          /* chain of redir instances */
	u_int16_t               mode;           /* type of redirect mode */
	struct in_addr	        laddr;          /* local ip address */
	struct in_addr	        paddr;          /* public ip address */
	struct in_addr	        raddr;          /* remote ip address */
	u_short                 lport;          /* local port */
	u_short                 pport;          /* public port */
	u_short                 rport;          /* remote port  */
	u_short                 pport_cnt;      /* number of public ports */
	u_short                 rport_cnt;      /* number of remote ports */
	int                     proto;          /* protocol: tcp/udp */
	struct alias_link       **alink;	
	/* num of entry in spool chain */
	u_int16_t               spool_cnt;      
	/* chain of spool instances */
	LIST_HEAD(spool_chain, cfg_spool) spool_chain;
};
#endif

#define NAT_BUF_LEN     1024

#ifdef IPFW_INTERNAL
/* Nat configuration data struct. */
struct cfg_nat {
	/* chain of nat instances */
	LIST_ENTRY(cfg_nat)     _next;
	int                     id;                     /* nat id */
	struct in_addr          ip;                     /* nat ip address */
	char                    if_name[IF_NAMESIZE];   /* interface name */
	int                     mode;                   /* aliasing mode */
	struct libalias	        *lib;                   /* libalias instance */
	/* number of entry in spool chain */
	int                     redir_cnt;              
	/* chain of redir instances */
	LIST_HEAD(redir_chain, cfg_redir) redir_chain;  
};
#endif

#define SOF_NAT         sizeof(struct cfg_nat)
#define SOF_REDIR       sizeof(struct cfg_redir)
#define SOF_SPOOL       sizeof(struct cfg_spool)

/* Nat command. */
typedef struct	_ipfw_insn_nat {
 	ipfw_insn	o;
 	struct cfg_nat *nat;	
} ipfw_insn_nat;

/* Apply ipv6 mask on ipv6 addr */
#define APPLY_MASK(addr,mask)                          \
    (addr)->__u6_addr.__u6_addr32[0] &= (mask)->__u6_addr.__u6_addr32[0]; \
    (addr)->__u6_addr.__u6_addr32[1] &= (mask)->__u6_addr.__u6_addr32[1]; \
    (addr)->__u6_addr.__u6_addr32[2] &= (mask)->__u6_addr.__u6_addr32[2]; \
    (addr)->__u6_addr.__u6_addr32[3] &= (mask)->__u6_addr.__u6_addr32[3];

/* Structure for ipv6 */
typedef struct _ipfw_insn_ip6 {
       ipfw_insn o;
       struct in6_addr addr6;
       struct in6_addr mask6;
} ipfw_insn_ip6;

/* Used to support icmp6 types */
typedef struct _ipfw_insn_icmp6 {
       ipfw_insn o;
       uint32_t d[7]; /* XXX This number si related to the netinet/icmp6.h
                       *     define ICMP6_MAXTYPE
                       *     as follows: n = ICMP6_MAXTYPE/32 + 1
                        *     Actually is 203 
                       */
} ipfw_insn_icmp6;

/*
 * Here we have the structure representing an ipfw rule.
 *
 * It starts with a general area (with link fields and counters)
 * followed by an array of one or more instructions, which the code
 * accesses as an array of 32-bit values.
 *
 * Given a rule pointer  r:
 *
 *  r->cmd		is the start of the first instruction.
 *  ACTION_PTR(r)	is the start of the first action (things to do
 *			once a rule matched).
 *
 * When assembling instruction, remember the following:
 *
 *  + if a rule has a "keep-state" (or "limit") option, then the
 *	first instruction (at r->cmd) MUST BE an O_PROBE_STATE
 *  + if a rule has a "log" option, then the first action
 *	(at ACTION_PTR(r)) MUST be O_LOG
 *  + if a rule has an "altq" option, it comes after "log"
 *  + if a rule has an O_TAG option, it comes after "log" and "altq"
 *
 * NOTE: we use a simple linked list of rules because we never need
 * 	to delete a rule without scanning the list. We do not use
 *	queue(3) macros for portability and readability.
 */

struct ip_fw {
	struct ip_fw	*next;		/* linked list of rules		*/
	struct ip_fw	*next_rule;	/* ptr to next [skipto] rule	*/
	/* 'next_rule' is used to pass up 'set_disable' status		*/

	uint16_t	act_ofs;	/* offset of action in 32-bit units */
	uint16_t	cmd_len;	/* # of 32-bit words in cmd	*/
	uint16_t	rulenum;	/* rule number			*/
	uint8_t	set;		/* rule set (0..31)		*/
#define	RESVD_SET	31	/* set for default and persistent rules */
	uint8_t		_pad;		/* padding			*/
	uint32_t	id;		/* rule id */

	/* These fields are present in all rules.			*/
	uint64_t	pcnt;		/* Packet counter		*/
	uint64_t	bcnt;		/* Byte counter			*/
	uint32_t	timestamp;	/* tv_sec of last match		*/

	ipfw_insn	cmd[1];		/* storage for commands		*/
};

#define ACTION_PTR(rule)				\
	(ipfw_insn *)( (u_int32_t *)((rule)->cmd) + ((rule)->act_ofs) )

#define RULESIZE(rule)  (sizeof(struct ip_fw) + \
	((struct ip_fw *)(rule))->cmd_len * 4 - 4)

/*
 * This structure is used as a flow mask and a flow id for various
 * parts of the code.
 */
struct ipfw_flow_id {
	u_int32_t	dst_ip;
	u_int32_t	src_ip;
	u_int16_t	dst_port;
	u_int16_t	src_port;
	u_int8_t	fib;
	u_int8_t	proto;
	u_int8_t	flags;	/* protocol-specific flags */
	uint8_t		addr_type; /* 4 = ipv4, 6 = ipv6, 1=ether ? */
	struct in6_addr dst_ip6;	/* could also store MAC addr! */
	struct in6_addr src_ip6;
	u_int32_t	flow_id6;
	u_int32_t	frag_id6;
};

#define IS_IP6_FLOW_ID(id)	((id)->addr_type == 6)

/*
 * Dynamic ipfw rule.
 */
typedef struct _ipfw_dyn_rule ipfw_dyn_rule;

struct _ipfw_dyn_rule {
	ipfw_dyn_rule	*next;		/* linked list of rules.	*/
	struct ip_fw *rule;		/* pointer to rule		*/
	/* 'rule' is used to pass up the rule number (from the parent)	*/

	ipfw_dyn_rule *parent;		/* pointer to parent rule	*/
	u_int64_t	pcnt;		/* packet match counter		*/
	u_int64_t	bcnt;		/* byte match counter		*/
	struct ipfw_flow_id id;		/* (masked) flow id		*/
	u_int32_t	expire;		/* expire time			*/
	u_int32_t	bucket;		/* which bucket in hash table	*/
	u_int32_t	state;		/* state of this rule (typically a
					 * combination of TCP flags)
					 */
	u_int32_t	ack_fwd;	/* most recent ACKs in forward	*/
	u_int32_t	ack_rev;	/* and reverse directions (used	*/
					/* to generate keepalives)	*/
	u_int16_t	dyn_type;	/* rule type			*/
	u_int16_t	count;		/* refcount			*/
};

/*
 * Definitions for IP option names.
 */
#define	IP_FW_IPOPT_LSRR	0x01
#define	IP_FW_IPOPT_SSRR	0x02
#define	IP_FW_IPOPT_RR		0x04
#define	IP_FW_IPOPT_TS		0x08

/*
 * Definitions for TCP option names.
 */
#define	IP_FW_TCPOPT_MSS	0x01
#define	IP_FW_TCPOPT_WINDOW	0x02
#define	IP_FW_TCPOPT_SACK	0x04
#define	IP_FW_TCPOPT_TS		0x08
#define	IP_FW_TCPOPT_CC		0x10

#define	ICMP_REJECT_RST		0x100	/* fake ICMP code (send a TCP RST) */
#define	ICMP6_UNREACH_RST	0x100	/* fake ICMPv6 code (send a TCP RST) */

/*
 * These are used for lookup tables.
 */
typedef struct	_ipfw_table_entry {
	in_addr_t	addr;		/* network address		*/
	u_int32_t	value;		/* value			*/
	u_int16_t	tbl;		/* table number			*/
	u_int8_t	masklen;	/* mask length			*/
} ipfw_table_entry;

typedef struct	_ipfw_table {
	u_int32_t	size;		/* size of entries in bytes	*/
	u_int32_t	cnt;		/* # of entries			*/
	u_int16_t	tbl;		/* table number			*/
	ipfw_table_entry ent[0];	/* entries			*/
} ipfw_table;

/*
 * Main firewall chains definitions and global var's definitions.
 */
#ifdef _KERNEL

#define MTAG_IPFW	1148380143	/* IPFW-tagged cookie */

/* Return values from ipfw_chk() */
enum {
	IP_FW_PASS = 0,
	IP_FW_DENY,
	IP_FW_DIVERT,
	IP_FW_TEE,
	IP_FW_DUMMYNET,
	IP_FW_NETGRAPH,
	IP_FW_NGTEE,
	IP_FW_NAT,
	IP_FW_REASS,
};

/* flags for divert mtag */
#define	IP_FW_DIVERT_LOOPBACK_FLAG	0x00080000
#define	IP_FW_DIVERT_OUTPUT_FLAG	0x00100000

/*
 * Structure for collecting parameters to dummynet for ip6_output forwarding
 */
struct _ip6dn_args {
       struct ip6_pktopts *opt_or;
       struct route_in6 ro_or;
       int flags_or;
       struct ip6_moptions *im6o_or;
       struct ifnet *origifp_or;
       struct ifnet *ifp_or;
       struct sockaddr_in6 dst_or;
       u_long mtu_or;
       struct route_in6 ro_pmtu_or;
};

/*
 * Arguments for calling ipfw_chk() and dummynet_io(). We put them
 * all into a structure because this way it is easier and more
 * efficient to pass variables around and extend the interface.
 */
struct ip_fw_args {
	struct mbuf	*m;		/* the mbuf chain		*/
	struct ifnet	*oif;		/* output interface		*/
	struct sockaddr_in *next_hop;	/* forward address		*/
	struct ip_fw	*rule;		/* matching rule		*/
	uint32_t	rule_id;	/* matching rule id */
	uint32_t	chain_id;	/* ruleset id */
	struct ether_header *eh;	/* for bridged packets		*/

	struct ipfw_flow_id f_id;	/* grabbed from IP header	*/
	uint32_t	cookie;		/* a cookie depending on rule action */
	struct inpcb	*inp;

	struct _ip6dn_args	dummypar; /* dummynet->ip6_output */
	struct sockaddr_in hopstore;	/* store here if cannot use a pointer */
};

/*
 * Function definitions.
 */

/* Firewall hooks */
struct sockopt;
struct dn_flow_set;

int ipfw_check_in(void *, struct mbuf **, struct ifnet *, int, struct inpcb *inp);
int ipfw_check_out(void *, struct mbuf **, struct ifnet *, int, struct inpcb *inp);

int ipfw_chk(struct ip_fw_args *);

int ipfw_init(void);
void ipfw_destroy(void);
#ifdef NOTYET
void ipfw_nat_destroy(void);
#endif

VNET_DECLARE(int, fw_one_pass);
VNET_DECLARE(int, fw_enable);
#define	V_fw_one_pass		VNET(fw_one_pass)
#define	V_fw_enable		VNET(fw_enable)

#ifdef INET6
VNET_DECLARE(int, fw6_enable);
#define	V_fw6_enable		VNET(fw6_enable)
#endif

struct ip_fw_chain {
	struct ip_fw	*rules;		/* list of rules */
	struct ip_fw	*reap;		/* list of rules to reap */
	LIST_HEAD(, cfg_nat) nat;       /* list of nat entries */
	struct radix_node_head *tables[IPFW_TABLES_MAX];
	struct rwlock	rwmtx;
	uint32_t	id;		/* ruleset id */
};

#ifdef IPFW_INTERNAL

#define	IPFW_LOCK_INIT(_chain) \
	rw_init(&(_chain)->rwmtx, "IPFW static rules")
#define	IPFW_LOCK_DESTROY(_chain)	rw_destroy(&(_chain)->rwmtx)
#define	IPFW_WLOCK_ASSERT(_chain)	rw_assert(&(_chain)->rwmtx, RA_WLOCKED)

#define IPFW_RLOCK(p) rw_rlock(&(p)->rwmtx)
#define IPFW_RUNLOCK(p) rw_runlock(&(p)->rwmtx)
#define IPFW_WLOCK(p) rw_wlock(&(p)->rwmtx)
#define IPFW_WUNLOCK(p) rw_wunlock(&(p)->rwmtx)

#define LOOKUP_NAT(l, i, p) do {					\
		LIST_FOREACH((p), &(l.nat), _next) {			\
			if ((p)->id == (i)) {				\
				break;					\
			} 						\
		}							\
	} while (0)

typedef int ipfw_nat_t(struct ip_fw_args *, struct cfg_nat *, struct mbuf *);
typedef int ipfw_nat_cfg_t(struct sockopt *);
#endif

VNET_DECLARE(struct ip_fw_chain, layer3_chain);
#define	V_layer3_chain		VNET(layer3_chain)

#endif /* _KERNEL */
#endif /* _IPFW2_H */