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 *
| 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 *
|
26 */
27
28#ifndef _IPFW2_H
29#define _IPFW2_H
30#define IPFW2 1
31
32/*
33 * The kernel representation of ipfw rules is made of a list of
34 * 'instructions' (for all practical purposes equivalent to BPF
35 * instructions), which specify which fields of the packet
36 * (or its metadata) should be analysed.
37 *
38 * Each instruction is stored in a structure which begins with
39 * "ipfw_insn", and can contain extra fields depending on the
40 * instruction type (listed below).
41 * Note that the code is written so that individual instructions
42 * have a size which is a multiple of 32 bits. This means that, if
43 * such structures contain pointers or other 64-bit entities,
44 * (there is just one instance now) they may end up unaligned on
45 * 64-bit architectures, so the must be handled with care.
46 *
47 * "enum ipfw_opcodes" are the opcodes supported. We can have up
48 * to 256 different opcodes. When adding new opcodes, they should
49 * be appended to the end of the opcode list before O_LAST_OPCODE,
50 * this will prevent the ABI from being broken, otherwise users
51 * will have to recompile ipfw(8) when they update the kernel.
52 */
53
54enum ipfw_opcodes { /* arguments (4 byte each) */
55 O_NOP,
56
57 O_IP_SRC, /* u32 = IP */
58 O_IP_SRC_MASK, /* ip = IP/mask */
59 O_IP_SRC_ME, /* none */
60 O_IP_SRC_SET, /* u32=base, arg1=len, bitmap */
61
62 O_IP_DST, /* u32 = IP */
63 O_IP_DST_MASK, /* ip = IP/mask */
64 O_IP_DST_ME, /* none */
65 O_IP_DST_SET, /* u32=base, arg1=len, bitmap */
66
67 O_IP_SRCPORT, /* (n)port list:mask 4 byte ea */
68 O_IP_DSTPORT, /* (n)port list:mask 4 byte ea */
69 O_PROTO, /* arg1=protocol */
70
71 O_MACADDR2, /* 2 mac addr:mask */
72 O_MAC_TYPE, /* same as srcport */
73
74 O_LAYER2, /* none */
75 O_IN, /* none */
76 O_FRAG, /* none */
77
78 O_RECV, /* none */
79 O_XMIT, /* none */
80 O_VIA, /* none */
81
82 O_IPOPT, /* arg1 = 2*u8 bitmap */
83 O_IPLEN, /* arg1 = len */
84 O_IPID, /* arg1 = id */
85
86 O_IPTOS, /* arg1 = id */
87 O_IPPRECEDENCE, /* arg1 = precedence << 5 */
88 O_IPTTL, /* arg1 = TTL */
89
90 O_IPVER, /* arg1 = version */
91 O_UID, /* u32 = id */
92 O_GID, /* u32 = id */
93 O_ESTAB, /* none (tcp established) */
94 O_TCPFLAGS, /* arg1 = 2*u8 bitmap */
95 O_TCPWIN, /* arg1 = desired win */
96 O_TCPSEQ, /* u32 = desired seq. */
97 O_TCPACK, /* u32 = desired seq. */
98 O_ICMPTYPE, /* u32 = icmp bitmap */
99 O_TCPOPTS, /* arg1 = 2*u8 bitmap */
100
101 O_VERREVPATH, /* none */
102 O_VERSRCREACH, /* none */
103
104 O_PROBE_STATE, /* none */
105 O_KEEP_STATE, /* none */
106 O_LIMIT, /* ipfw_insn_limit */
107 O_LIMIT_PARENT, /* dyn_type, not an opcode. */
108
109 /*
110 * These are really 'actions'.
111 */
112
113 O_LOG, /* ipfw_insn_log */
114 O_PROB, /* u32 = match probability */
115
116 O_CHECK_STATE, /* none */
117 O_ACCEPT, /* none */
118 O_DENY, /* none */
119 O_REJECT, /* arg1=icmp arg (same as deny) */
120 O_COUNT, /* none */
121 O_SKIPTO, /* arg1=next rule number */
122 O_PIPE, /* arg1=pipe number */
123 O_QUEUE, /* arg1=queue number */
124 O_DIVERT, /* arg1=port number */
125 O_TEE, /* arg1=port number */
126 O_FORWARD_IP, /* fwd sockaddr */
127 O_FORWARD_MAC, /* fwd mac */
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
138 O_LAST_OPCODE /* not an opcode! */
139};
140
141/*
142 * Template for instructions.
143 *
144 * ipfw_insn is used for all instructions which require no operands,
145 * a single 16-bit value (arg1), or a couple of 8-bit values.
146 *
147 * For other instructions which require different/larger arguments
148 * we have derived structures, ipfw_insn_*.
149 *
150 * The size of the instruction (in 32-bit words) is in the low
151 * 6 bits of "len". The 2 remaining bits are used to implement
152 * NOT and OR on individual instructions. Given a type, you can
153 * compute the length to be put in "len" using F_INSN_SIZE(t)
154 *
155 * F_NOT negates the match result of the instruction.
156 *
157 * F_OR is used to build or blocks. By default, instructions
158 * are evaluated as part of a logical AND. An "or" block
159 * { X or Y or Z } contains F_OR set in all but the last
160 * instruction of the block. A match will cause the code
161 * to skip past the last instruction of the block.
162 *
163 * NOTA BENE: in a couple of places we assume that
164 * sizeof(ipfw_insn) == sizeof(u_int32_t)
165 * this needs to be fixed.
166 *
167 */
168typedef struct _ipfw_insn { /* template for instructions */
169 enum ipfw_opcodes opcode:8;
170 u_int8_t len; /* numer of 32-byte words */
171#define F_NOT 0x80
172#define F_OR 0x40
173#define F_LEN_MASK 0x3f
174#define F_LEN(cmd) ((cmd)->len & F_LEN_MASK)
175
176 u_int16_t arg1;
177} ipfw_insn;
178
179/*
180 * The F_INSN_SIZE(type) computes the size, in 4-byte words, of
181 * a given type.
182 */
183#define F_INSN_SIZE(t) ((sizeof (t))/sizeof(u_int32_t))
184
185/*
186 * This is used to store an array of 16-bit entries (ports etc.)
187 */
188typedef struct _ipfw_insn_u16 {
189 ipfw_insn o;
190 u_int16_t ports[2]; /* there may be more */
191} ipfw_insn_u16;
192
193/*
194 * This is used to store an array of 32-bit entries
195 * (uid, single IPv4 addresses etc.)
196 */
197typedef struct _ipfw_insn_u32 {
198 ipfw_insn o;
199 u_int32_t d[1]; /* one or more */
200} ipfw_insn_u32;
201
202/*
203 * This is used to store IP addr-mask pairs.
204 */
205typedef struct _ipfw_insn_ip {
206 ipfw_insn o;
207 struct in_addr addr;
208 struct in_addr mask;
209} ipfw_insn_ip;
210
211/*
212 * This is used to forward to a given address (ip).
213 */
214typedef struct _ipfw_insn_sa {
215 ipfw_insn o;
216 struct sockaddr_in sa;
217} ipfw_insn_sa;
218
219/*
220 * This is used for MAC addr-mask pairs.
221 */
222typedef struct _ipfw_insn_mac {
223 ipfw_insn o;
224 u_char addr[12]; /* dst[6] + src[6] */
225 u_char mask[12]; /* dst[6] + src[6] */
226} ipfw_insn_mac;
227
228/*
229 * This is used for interface match rules (recv xx, xmit xx).
230 */
231typedef struct _ipfw_insn_if {
232 ipfw_insn o;
233 union {
234 struct in_addr ip;
235 int glob;
236 } p;
237 char name[IFNAMSIZ];
238} ipfw_insn_if;
239
240/*
241 * This is used for pipe and queue actions, which need to store
242 * a single pointer (which can have different size on different
243 * architectures.
244 * Note that, because of previous instructions, pipe_ptr might
245 * be unaligned in the overall structure, so it needs to be
246 * manipulated with care.
247 */
248typedef struct _ipfw_insn_pipe {
249 ipfw_insn o;
250 void *pipe_ptr; /* XXX */
251} ipfw_insn_pipe;
252
253/*
254 * This is used for limit rules.
255 */
256typedef struct _ipfw_insn_limit {
257 ipfw_insn o;
258 u_int8_t _pad;
259 u_int8_t limit_mask; /* combination of DYN_* below */
260#define DYN_SRC_ADDR 0x1
261#define DYN_SRC_PORT 0x2
262#define DYN_DST_ADDR 0x4
263#define DYN_DST_PORT 0x8
264
265 u_int16_t conn_limit;
266} ipfw_insn_limit;
267
268/*
269 * This is used for log instructions.
270 */
271typedef struct _ipfw_insn_log {
272 ipfw_insn o;
273 u_int32_t max_log; /* how many do we log -- 0 = all */
274 u_int32_t log_left; /* how many left to log */
275} ipfw_insn_log;
276
277/*
278 * Here we have the structure representing an ipfw rule.
279 *
280 * It starts with a general area (with link fields and counters)
281 * followed by an array of one or more instructions, which the code
282 * accesses as an array of 32-bit values.
283 *
284 * Given a rule pointer r:
285 *
286 * r->cmd is the start of the first instruction.
287 * ACTION_PTR(r) is the start of the first action (things to do
288 * once a rule matched).
289 *
290 * When assembling instruction, remember the following:
291 *
292 * + if a rule has a "keep-state" (or "limit") option, then the
293 * first instruction (at r->cmd) MUST BE an O_PROBE_STATE
294 * + if a rule has a "log" option, then the first action
295 * (at ACTION_PTR(r)) MUST be O_LOG
296 *
297 * NOTE: we use a simple linked list of rules because we never need
298 * to delete a rule without scanning the list. We do not use
299 * queue(3) macros for portability and readability.
300 */
301
302struct ip_fw {
303 struct ip_fw *next; /* linked list of rules */
304 struct ip_fw *next_rule; /* ptr to next [skipto] rule */
305 /* 'next_rule' is used to pass up 'set_disable' status */
306
307 u_int16_t act_ofs; /* offset of action in 32-bit units */
308 u_int16_t cmd_len; /* # of 32-bit words in cmd */
309 u_int16_t rulenum; /* rule number */
310 u_int8_t set; /* rule set (0..31) */
311#define RESVD_SET 31 /* set for default and persistent rules */
312 u_int8_t _pad; /* padding */
313
314 /* These fields are present in all rules. */
315 u_int64_t pcnt; /* Packet counter */
316 u_int64_t bcnt; /* Byte counter */
317 u_int32_t timestamp; /* tv_sec of last match */
318
319 ipfw_insn cmd[1]; /* storage for commands */
320};
321
322#define ACTION_PTR(rule) \
323 (ipfw_insn *)( (u_int32_t *)((rule)->cmd) + ((rule)->act_ofs) )
324
325#define RULESIZE(rule) (sizeof(struct ip_fw) + \
326 ((struct ip_fw *)(rule))->cmd_len * 4 - 4)
327
328/*
329 * This structure is used as a flow mask and a flow id for various
330 * parts of the code.
331 */
332struct ipfw_flow_id {
333 u_int32_t dst_ip;
334 u_int32_t src_ip;
335 u_int16_t dst_port;
336 u_int16_t src_port;
337 u_int8_t proto;
338 u_int8_t flags; /* protocol-specific flags */
339};
340
341/*
342 * Dynamic ipfw rule.
343 */
344typedef struct _ipfw_dyn_rule ipfw_dyn_rule;
345
346struct _ipfw_dyn_rule {
347 ipfw_dyn_rule *next; /* linked list of rules. */
348 struct ip_fw *rule; /* pointer to rule */
349 /* 'rule' is used to pass up the rule number (from the parent) */
350
351 ipfw_dyn_rule *parent; /* pointer to parent rule */
352 u_int64_t pcnt; /* packet match counter */
353 u_int64_t bcnt; /* byte match counter */
354 struct ipfw_flow_id id; /* (masked) flow id */
355 u_int32_t expire; /* expire time */
356 u_int32_t bucket; /* which bucket in hash table */
357 u_int32_t state; /* state of this rule (typically a
358 * combination of TCP flags)
359 */
360 u_int32_t ack_fwd; /* most recent ACKs in forward */
361 u_int32_t ack_rev; /* and reverse directions (used */
362 /* to generate keepalives) */
363 u_int16_t dyn_type; /* rule type */
364 u_int16_t count; /* refcount */
365};
366
367/*
368 * Definitions for IP option names.
369 */
370#define IP_FW_IPOPT_LSRR 0x01
371#define IP_FW_IPOPT_SSRR 0x02
372#define IP_FW_IPOPT_RR 0x04
373#define IP_FW_IPOPT_TS 0x08
374
375/*
376 * Definitions for TCP option names.
377 */
378#define IP_FW_TCPOPT_MSS 0x01
379#define IP_FW_TCPOPT_WINDOW 0x02
380#define IP_FW_TCPOPT_SACK 0x04
381#define IP_FW_TCPOPT_TS 0x08
382#define IP_FW_TCPOPT_CC 0x10
383
384#define ICMP_REJECT_RST 0x100 /* fake ICMP code (send a TCP RST) */
385
386/*
387 * These are used for lookup tables.
388 */
389typedef struct _ipfw_table_entry {
390 in_addr_t addr; /* network address */
391 u_int32_t value; /* value */
392 u_int16_t tbl; /* table number */
393 u_int8_t masklen; /* mask length */
394} ipfw_table_entry;
395
396typedef struct _ipfw_table {
397 u_int32_t size; /* size of entries in bytes */
398 u_int32_t cnt; /* # of entries */
399 u_int16_t tbl; /* table number */
400 ipfw_table_entry ent[0]; /* entries */
401} ipfw_table;
402
403/*
404 * Main firewall chains definitions and global var's definitions.
405 */
406#ifdef _KERNEL
407
408#define IP_FW_PORT_DYNT_FLAG 0x10000
409#define IP_FW_PORT_TEE_FLAG 0x20000
410#define IP_FW_PORT_DENY_FLAG 0x40000
411
412/*
413 * Arguments for calling ipfw_chk() and dummynet_io(). We put them
414 * all into a structure because this way it is easier and more
415 * efficient to pass variables around and extend the interface.
416 */
417struct ip_fw_args {
418 struct mbuf *m; /* the mbuf chain */
419 struct ifnet *oif; /* output interface */
420 struct sockaddr_in *next_hop; /* forward address */
421 struct ip_fw *rule; /* matching rule */
422 struct ether_header *eh; /* for bridged packets */
423
424 int flags; /* for dummynet */
425
426 struct ipfw_flow_id f_id; /* grabbed from IP header */
427 u_int32_t retval;
| 26 */
27
28#ifndef _IPFW2_H
29#define _IPFW2_H
30#define IPFW2 1
31
32/*
33 * The kernel representation of ipfw rules is made of a list of
34 * 'instructions' (for all practical purposes equivalent to BPF
35 * instructions), which specify which fields of the packet
36 * (or its metadata) should be analysed.
37 *
38 * Each instruction is stored in a structure which begins with
39 * "ipfw_insn", and can contain extra fields depending on the
40 * instruction type (listed below).
41 * Note that the code is written so that individual instructions
42 * have a size which is a multiple of 32 bits. This means that, if
43 * such structures contain pointers or other 64-bit entities,
44 * (there is just one instance now) they may end up unaligned on
45 * 64-bit architectures, so the must be handled with care.
46 *
47 * "enum ipfw_opcodes" are the opcodes supported. We can have up
48 * to 256 different opcodes. When adding new opcodes, they should
49 * be appended to the end of the opcode list before O_LAST_OPCODE,
50 * this will prevent the ABI from being broken, otherwise users
51 * will have to recompile ipfw(8) when they update the kernel.
52 */
53
54enum ipfw_opcodes { /* arguments (4 byte each) */
55 O_NOP,
56
57 O_IP_SRC, /* u32 = IP */
58 O_IP_SRC_MASK, /* ip = IP/mask */
59 O_IP_SRC_ME, /* none */
60 O_IP_SRC_SET, /* u32=base, arg1=len, bitmap */
61
62 O_IP_DST, /* u32 = IP */
63 O_IP_DST_MASK, /* ip = IP/mask */
64 O_IP_DST_ME, /* none */
65 O_IP_DST_SET, /* u32=base, arg1=len, bitmap */
66
67 O_IP_SRCPORT, /* (n)port list:mask 4 byte ea */
68 O_IP_DSTPORT, /* (n)port list:mask 4 byte ea */
69 O_PROTO, /* arg1=protocol */
70
71 O_MACADDR2, /* 2 mac addr:mask */
72 O_MAC_TYPE, /* same as srcport */
73
74 O_LAYER2, /* none */
75 O_IN, /* none */
76 O_FRAG, /* none */
77
78 O_RECV, /* none */
79 O_XMIT, /* none */
80 O_VIA, /* none */
81
82 O_IPOPT, /* arg1 = 2*u8 bitmap */
83 O_IPLEN, /* arg1 = len */
84 O_IPID, /* arg1 = id */
85
86 O_IPTOS, /* arg1 = id */
87 O_IPPRECEDENCE, /* arg1 = precedence << 5 */
88 O_IPTTL, /* arg1 = TTL */
89
90 O_IPVER, /* arg1 = version */
91 O_UID, /* u32 = id */
92 O_GID, /* u32 = id */
93 O_ESTAB, /* none (tcp established) */
94 O_TCPFLAGS, /* arg1 = 2*u8 bitmap */
95 O_TCPWIN, /* arg1 = desired win */
96 O_TCPSEQ, /* u32 = desired seq. */
97 O_TCPACK, /* u32 = desired seq. */
98 O_ICMPTYPE, /* u32 = icmp bitmap */
99 O_TCPOPTS, /* arg1 = 2*u8 bitmap */
100
101 O_VERREVPATH, /* none */
102 O_VERSRCREACH, /* none */
103
104 O_PROBE_STATE, /* none */
105 O_KEEP_STATE, /* none */
106 O_LIMIT, /* ipfw_insn_limit */
107 O_LIMIT_PARENT, /* dyn_type, not an opcode. */
108
109 /*
110 * These are really 'actions'.
111 */
112
113 O_LOG, /* ipfw_insn_log */
114 O_PROB, /* u32 = match probability */
115
116 O_CHECK_STATE, /* none */
117 O_ACCEPT, /* none */
118 O_DENY, /* none */
119 O_REJECT, /* arg1=icmp arg (same as deny) */
120 O_COUNT, /* none */
121 O_SKIPTO, /* arg1=next rule number */
122 O_PIPE, /* arg1=pipe number */
123 O_QUEUE, /* arg1=queue number */
124 O_DIVERT, /* arg1=port number */
125 O_TEE, /* arg1=port number */
126 O_FORWARD_IP, /* fwd sockaddr */
127 O_FORWARD_MAC, /* fwd mac */
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
138 O_LAST_OPCODE /* not an opcode! */
139};
140
141/*
142 * Template for instructions.
143 *
144 * ipfw_insn is used for all instructions which require no operands,
145 * a single 16-bit value (arg1), or a couple of 8-bit values.
146 *
147 * For other instructions which require different/larger arguments
148 * we have derived structures, ipfw_insn_*.
149 *
150 * The size of the instruction (in 32-bit words) is in the low
151 * 6 bits of "len". The 2 remaining bits are used to implement
152 * NOT and OR on individual instructions. Given a type, you can
153 * compute the length to be put in "len" using F_INSN_SIZE(t)
154 *
155 * F_NOT negates the match result of the instruction.
156 *
157 * F_OR is used to build or blocks. By default, instructions
158 * are evaluated as part of a logical AND. An "or" block
159 * { X or Y or Z } contains F_OR set in all but the last
160 * instruction of the block. A match will cause the code
161 * to skip past the last instruction of the block.
162 *
163 * NOTA BENE: in a couple of places we assume that
164 * sizeof(ipfw_insn) == sizeof(u_int32_t)
165 * this needs to be fixed.
166 *
167 */
168typedef struct _ipfw_insn { /* template for instructions */
169 enum ipfw_opcodes opcode:8;
170 u_int8_t len; /* numer of 32-byte words */
171#define F_NOT 0x80
172#define F_OR 0x40
173#define F_LEN_MASK 0x3f
174#define F_LEN(cmd) ((cmd)->len & F_LEN_MASK)
175
176 u_int16_t arg1;
177} ipfw_insn;
178
179/*
180 * The F_INSN_SIZE(type) computes the size, in 4-byte words, of
181 * a given type.
182 */
183#define F_INSN_SIZE(t) ((sizeof (t))/sizeof(u_int32_t))
184
185/*
186 * This is used to store an array of 16-bit entries (ports etc.)
187 */
188typedef struct _ipfw_insn_u16 {
189 ipfw_insn o;
190 u_int16_t ports[2]; /* there may be more */
191} ipfw_insn_u16;
192
193/*
194 * This is used to store an array of 32-bit entries
195 * (uid, single IPv4 addresses etc.)
196 */
197typedef struct _ipfw_insn_u32 {
198 ipfw_insn o;
199 u_int32_t d[1]; /* one or more */
200} ipfw_insn_u32;
201
202/*
203 * This is used to store IP addr-mask pairs.
204 */
205typedef struct _ipfw_insn_ip {
206 ipfw_insn o;
207 struct in_addr addr;
208 struct in_addr mask;
209} ipfw_insn_ip;
210
211/*
212 * This is used to forward to a given address (ip).
213 */
214typedef struct _ipfw_insn_sa {
215 ipfw_insn o;
216 struct sockaddr_in sa;
217} ipfw_insn_sa;
218
219/*
220 * This is used for MAC addr-mask pairs.
221 */
222typedef struct _ipfw_insn_mac {
223 ipfw_insn o;
224 u_char addr[12]; /* dst[6] + src[6] */
225 u_char mask[12]; /* dst[6] + src[6] */
226} ipfw_insn_mac;
227
228/*
229 * This is used for interface match rules (recv xx, xmit xx).
230 */
231typedef struct _ipfw_insn_if {
232 ipfw_insn o;
233 union {
234 struct in_addr ip;
235 int glob;
236 } p;
237 char name[IFNAMSIZ];
238} ipfw_insn_if;
239
240/*
241 * This is used for pipe and queue actions, which need to store
242 * a single pointer (which can have different size on different
243 * architectures.
244 * Note that, because of previous instructions, pipe_ptr might
245 * be unaligned in the overall structure, so it needs to be
246 * manipulated with care.
247 */
248typedef struct _ipfw_insn_pipe {
249 ipfw_insn o;
250 void *pipe_ptr; /* XXX */
251} ipfw_insn_pipe;
252
253/*
254 * This is used for limit rules.
255 */
256typedef struct _ipfw_insn_limit {
257 ipfw_insn o;
258 u_int8_t _pad;
259 u_int8_t limit_mask; /* combination of DYN_* below */
260#define DYN_SRC_ADDR 0x1
261#define DYN_SRC_PORT 0x2
262#define DYN_DST_ADDR 0x4
263#define DYN_DST_PORT 0x8
264
265 u_int16_t conn_limit;
266} ipfw_insn_limit;
267
268/*
269 * This is used for log instructions.
270 */
271typedef struct _ipfw_insn_log {
272 ipfw_insn o;
273 u_int32_t max_log; /* how many do we log -- 0 = all */
274 u_int32_t log_left; /* how many left to log */
275} ipfw_insn_log;
276
277/*
278 * Here we have the structure representing an ipfw rule.
279 *
280 * It starts with a general area (with link fields and counters)
281 * followed by an array of one or more instructions, which the code
282 * accesses as an array of 32-bit values.
283 *
284 * Given a rule pointer r:
285 *
286 * r->cmd is the start of the first instruction.
287 * ACTION_PTR(r) is the start of the first action (things to do
288 * once a rule matched).
289 *
290 * When assembling instruction, remember the following:
291 *
292 * + if a rule has a "keep-state" (or "limit") option, then the
293 * first instruction (at r->cmd) MUST BE an O_PROBE_STATE
294 * + if a rule has a "log" option, then the first action
295 * (at ACTION_PTR(r)) MUST be O_LOG
296 *
297 * NOTE: we use a simple linked list of rules because we never need
298 * to delete a rule without scanning the list. We do not use
299 * queue(3) macros for portability and readability.
300 */
301
302struct ip_fw {
303 struct ip_fw *next; /* linked list of rules */
304 struct ip_fw *next_rule; /* ptr to next [skipto] rule */
305 /* 'next_rule' is used to pass up 'set_disable' status */
306
307 u_int16_t act_ofs; /* offset of action in 32-bit units */
308 u_int16_t cmd_len; /* # of 32-bit words in cmd */
309 u_int16_t rulenum; /* rule number */
310 u_int8_t set; /* rule set (0..31) */
311#define RESVD_SET 31 /* set for default and persistent rules */
312 u_int8_t _pad; /* padding */
313
314 /* These fields are present in all rules. */
315 u_int64_t pcnt; /* Packet counter */
316 u_int64_t bcnt; /* Byte counter */
317 u_int32_t timestamp; /* tv_sec of last match */
318
319 ipfw_insn cmd[1]; /* storage for commands */
320};
321
322#define ACTION_PTR(rule) \
323 (ipfw_insn *)( (u_int32_t *)((rule)->cmd) + ((rule)->act_ofs) )
324
325#define RULESIZE(rule) (sizeof(struct ip_fw) + \
326 ((struct ip_fw *)(rule))->cmd_len * 4 - 4)
327
328/*
329 * This structure is used as a flow mask and a flow id for various
330 * parts of the code.
331 */
332struct ipfw_flow_id {
333 u_int32_t dst_ip;
334 u_int32_t src_ip;
335 u_int16_t dst_port;
336 u_int16_t src_port;
337 u_int8_t proto;
338 u_int8_t flags; /* protocol-specific flags */
339};
340
341/*
342 * Dynamic ipfw rule.
343 */
344typedef struct _ipfw_dyn_rule ipfw_dyn_rule;
345
346struct _ipfw_dyn_rule {
347 ipfw_dyn_rule *next; /* linked list of rules. */
348 struct ip_fw *rule; /* pointer to rule */
349 /* 'rule' is used to pass up the rule number (from the parent) */
350
351 ipfw_dyn_rule *parent; /* pointer to parent rule */
352 u_int64_t pcnt; /* packet match counter */
353 u_int64_t bcnt; /* byte match counter */
354 struct ipfw_flow_id id; /* (masked) flow id */
355 u_int32_t expire; /* expire time */
356 u_int32_t bucket; /* which bucket in hash table */
357 u_int32_t state; /* state of this rule (typically a
358 * combination of TCP flags)
359 */
360 u_int32_t ack_fwd; /* most recent ACKs in forward */
361 u_int32_t ack_rev; /* and reverse directions (used */
362 /* to generate keepalives) */
363 u_int16_t dyn_type; /* rule type */
364 u_int16_t count; /* refcount */
365};
366
367/*
368 * Definitions for IP option names.
369 */
370#define IP_FW_IPOPT_LSRR 0x01
371#define IP_FW_IPOPT_SSRR 0x02
372#define IP_FW_IPOPT_RR 0x04
373#define IP_FW_IPOPT_TS 0x08
374
375/*
376 * Definitions for TCP option names.
377 */
378#define IP_FW_TCPOPT_MSS 0x01
379#define IP_FW_TCPOPT_WINDOW 0x02
380#define IP_FW_TCPOPT_SACK 0x04
381#define IP_FW_TCPOPT_TS 0x08
382#define IP_FW_TCPOPT_CC 0x10
383
384#define ICMP_REJECT_RST 0x100 /* fake ICMP code (send a TCP RST) */
385
386/*
387 * These are used for lookup tables.
388 */
389typedef struct _ipfw_table_entry {
390 in_addr_t addr; /* network address */
391 u_int32_t value; /* value */
392 u_int16_t tbl; /* table number */
393 u_int8_t masklen; /* mask length */
394} ipfw_table_entry;
395
396typedef struct _ipfw_table {
397 u_int32_t size; /* size of entries in bytes */
398 u_int32_t cnt; /* # of entries */
399 u_int16_t tbl; /* table number */
400 ipfw_table_entry ent[0]; /* entries */
401} ipfw_table;
402
403/*
404 * Main firewall chains definitions and global var's definitions.
405 */
406#ifdef _KERNEL
407
408#define IP_FW_PORT_DYNT_FLAG 0x10000
409#define IP_FW_PORT_TEE_FLAG 0x20000
410#define IP_FW_PORT_DENY_FLAG 0x40000
411
412/*
413 * Arguments for calling ipfw_chk() and dummynet_io(). We put them
414 * all into a structure because this way it is easier and more
415 * efficient to pass variables around and extend the interface.
416 */
417struct ip_fw_args {
418 struct mbuf *m; /* the mbuf chain */
419 struct ifnet *oif; /* output interface */
420 struct sockaddr_in *next_hop; /* forward address */
421 struct ip_fw *rule; /* matching rule */
422 struct ether_header *eh; /* for bridged packets */
423
424 int flags; /* for dummynet */
425
426 struct ipfw_flow_id f_id; /* grabbed from IP header */
427 u_int32_t retval;
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