2 * Copyright (c) 2002 Luigi Rizzo, Universita` di Pisa
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
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.
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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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
25 * $FreeBSD: src/sys/netinet/ip_fw2.h,v 1.1.2.2 2002/08/16 11:03:11 luigi Exp $
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 metatada) should be analysed.
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).
41 * "enum ipfw_opcodes" are the opcodes supported. We can have up
42 * to 256 different opcodes.
45 enum ipfw_opcodes { /* arguments (4 byte each) */
48 O_IP_SRC, /* u32 = IP */
49 O_IP_SRC_MASK, /* ip = IP/mask */
50 O_IP_SRC_ME, /* none */
51 O_IP_SRC_SET, /* u32=base, arg1=len, bitmap */
53 O_IP_DST, /* u32 = IP */
54 O_IP_DST_MASK, /* ip = IP/mask */
55 O_IP_DST_ME, /* none */
56 O_IP_DST_SET, /* u32=base, arg1=len, bitmap */
58 O_IP_SRCPORT, /* (n)port list:mask 4 byte ea */
59 O_IP_DSTPORT, /* (n)port list:mask 4 byte ea */
60 O_PROTO, /* arg1=protocol */
62 O_MACADDR2, /* 2 mac addr:mask */
63 O_MAC_TYPE, /* same as srcport */
73 O_IPOPT, /* arg1 = 2*u8 bitmap */
74 O_IPLEN, /* arg1 = len */
75 O_IPID, /* arg1 = id */
77 O_IPTOS, /* arg1 = id */
78 O_IPPRECEDENCE, /* arg1 = precedence << 5 */
79 O_IPTTL, /* arg1 = TTL */
81 O_IPVER, /* arg1 = version */
84 O_ESTAB, /* none (tcp established) */
85 O_TCPFLAGS, /* arg1 = 2*u8 bitmap */
86 O_TCPWIN, /* arg1 = desired win */
87 O_TCPSEQ, /* u32 = desired seq. */
88 O_TCPACK, /* u32 = desired seq. */
89 O_ICMPTYPE, /* u32 = icmp bitmap */
90 O_TCPOPTS, /* arg1 = 2*u8 bitmap */
92 O_PROBE_STATE, /* none */
93 O_KEEP_STATE, /* none */
94 O_LIMIT, /* ipfw_insn_limit */
95 O_LIMIT_PARENT, /* dyn_type, not an opcode. */
97 * these are really 'actions', and must be last in the list.
100 O_LOG, /* ipfw_insn_log */
101 O_PROB, /* u32 = match probability */
103 O_CHECK_STATE, /* none */
106 O_REJECT, /* arg1=icmp arg (same as deny) */
108 O_SKIPTO, /* arg1=next rule number */
109 O_PIPE, /* arg1=pipe number */
110 O_QUEUE, /* arg1=queue number */
111 O_DIVERT, /* arg1=port number */
112 O_TEE, /* arg1=port number */
113 O_FORWARD_IP, /* fwd sockaddr */
114 O_FORWARD_MAC, /* fwd mac */
115 O_IP_SRC_TABLE, /* arg1 = tableid */
116 O_IP_DST_TABLE, /* arg1 = tableid */
117 O_LAST_OPCODE /* not an opcode! */
121 * Template for instructions.
123 * ipfw_insn is used for all instructions which require no operands,
124 * a single 16-bit value (arg1), or a couple of 8-bit values.
126 * For other instructions which require different/larger arguments
127 * we have derived structures, ipfw_insn_*.
129 * The size of the instruction (in 32-bit words) is in the low
130 * 6 bits of "len". The 2 remaining bits are used to implement
131 * NOT and OR on individual instructions. Given a type, you can
132 * compute the length to be put in "len" using F_INSN_SIZE(t)
134 * F_NOT negates the match result of the instruction.
136 * F_OR is used to build or blocks. By default, instructions
137 * are evaluated as part of a logical AND. An "or" block
138 * { X or Y or Z } contains F_OR set in all but the last
139 * instruction of the block. A match will cause the code
140 * to skip past the last instruction of the block.
142 * NOTA BENE: in a couple of places we assume that
143 * sizeof(ipfw_insn) == sizeof(uint32_t)
144 * this needs to be fixed.
147 typedef struct _ipfw_insn { /* template for instructions */
148 enum ipfw_opcodes opcode:8;
149 uint8_t len; /* numer of 32-byte words */
152 #define F_LEN_MASK 0x3f
153 #define F_LEN(cmd) ((cmd)->len & F_LEN_MASK)
159 * The F_INSN_SIZE(type) computes the size, in 4-byte words, of
162 #define F_INSN_SIZE(t) ((sizeof (t))/sizeof(uint32_t))
165 * This is used to store an array of 16-bit entries (ports etc.)
167 typedef struct _ipfw_insn_u16 {
169 uint16_t ports[2]; /* there may be more */
173 * This is used to store an array of 32-bit entries
174 * (uid, single IPv4 addresses etc.)
176 typedef struct _ipfw_insn_u32 {
178 uint32_t d[1]; /* one or more */
182 * This is used to store IP addr-mask pairs.
184 typedef struct _ipfw_insn_ip {
191 * This is used to forward to a given address (ip)
193 typedef struct _ipfw_insn_sa {
195 struct sockaddr_in sa;
199 * This is used for MAC addr-mask pairs.
201 typedef struct _ipfw_insn_mac {
203 u_char addr[12]; /* dst[6] + src[6] */
204 u_char mask[12]; /* dst[6] + src[6] */
208 * This is used for interface match rules (recv xx, xmit xx)
210 typedef struct _ipfw_insn_if {
220 * This is used for pipe and queue actions, which need to store
221 * a single pointer (which can have different size on different
224 typedef struct _ipfw_insn_pipe {
230 * This is used for limit rules.
232 typedef struct _ipfw_insn_limit {
235 uint8_t limit_mask; /* combination of DYN_* below */
236 #define DYN_SRC_ADDR 0x1
237 #define DYN_SRC_PORT 0x2
238 #define DYN_DST_ADDR 0x4
239 #define DYN_DST_PORT 0x8
245 * This is used for log instructions
247 typedef struct _ipfw_insn_log {
249 uint32_t max_log; /* how many do we log -- 0 = all */
250 uint32_t log_left; /* how many left to log */
256 * Here we have the structure representing an ipfw rule.
258 * It starts with a general area (with link fields and counters)
259 * followed by an array of one or more instructions, which the code
260 * accesses as an array of 32-bit values.
262 * Given a rule pointer r:
264 * r->cmd is the start of the first instruction.
265 * ACTION_PTR(r) is the start of the first action (things to do
266 * once a rule matched).
268 * When assembling instruction, remember the following:
270 * + if a rule has a "keep-state" (or "limit") option, then the
271 * first instruction (at r->cmd) MUST BE an O_PROBE_STATE
272 * + if a rule has a "log" option, then the first action
273 * (at ACTION_PTR(r)) MUST be O_LOG
275 * NOTE: we use a simple linked list of rules because we never need
276 * to delete a rule without scanning the list. We do not use
277 * queue(3) macros for portability and readability.
281 struct ip_fw *next; /* linked list of rules */
282 struct ip_fw *next_rule; /* ptr to next [skipto] rule */
283 uint16_t act_ofs; /* offset of action in 32-bit units */
284 uint16_t cmd_len; /* # of 32-bit words in cmd */
285 uint16_t rulenum; /* rule number */
286 uint8_t set; /* rule set (0..31) */
287 uint8_t usr_flags; /* IPFW_USR_F_ */
289 /* These fields are present in all rules. */
290 uint64_t pcnt; /* Packet counter */
291 uint64_t bcnt; /* Byte counter */
292 uint32_t timestamp; /* tv_sec of last match */
294 struct ip_fw *sibling; /* clone on next cpu */
295 int cpuid; /* owner cpu */
297 uint32_t refcnt; /* Ref count for transit pkts */
298 uint32_t rule_flags; /* IPFW_RULE_F_ */
299 uintptr_t track_ruleid; /* ruleid for src/dst tracks */
301 ipfw_insn cmd[1]; /* storage for commands */
304 #define IPFW_RULE_F_INVALID 0x1
306 #define IPFW_RULE_F_GENSTATE 0x4
307 #define IPFW_RULE_F_GENTRACK 0x8
309 #define RULESIZE(rule) (sizeof(struct ip_fw) + (rule)->cmd_len * 4 - 4)
312 * This structure is used as a flow mask and a flow id for various
315 struct ipfw_flow_id {
321 uint8_t flags; /* protocol-specific flags */
325 * Main firewall chains definitions and global var's definitions.
328 /* ipfw_chk/ip_fw_chk_ptr return values */
331 #define IP_FW_DIVERT 2
333 #define IP_FW_DUMMYNET 4
336 * arguments for calling ipfw_chk() and dummynet_io(). We put them
337 * all into a structure because this way it is easier and more
338 * efficient to pass variables around and extend the interface.
341 struct mbuf *m; /* the mbuf chain */
342 struct ifnet *oif; /* output interface */
343 struct ip_fw *rule; /* matching rule */
344 struct ether_header *eh; /* for bridged packets */
346 struct ipfw_flow_id f_id; /* grabbed from IP header */
349 * Depend on the return value of ipfw_chk/ip_fw_chk_ptr
350 * 'cookie' field may save following information:
352 * IP_FW_TEE or IP_FW_DIVERT
353 * The divert port number
356 * The pipe or queue number
362 * Function definitions.
364 int ip_fw_sockopt(struct sockopt *);
370 typedef int ip_fw_chk_t(struct ip_fw_args *);
371 typedef int ip_fw_ctl_t(struct sockopt *);
372 typedef void ip_fw_dn_io_t(struct mbuf *, int, int, struct ip_fw_args *);
374 extern ip_fw_chk_t *ip_fw_chk_ptr;
375 extern ip_fw_ctl_t *ip_fw_ctl_ptr;
376 extern ip_fw_dn_io_t *ip_fw_dn_io_ptr;
378 extern int fw_one_pass;
379 extern int fw_enable;
381 extern int ip_fw_loaded;
382 #define IPFW_LOADED (ip_fw_loaded)
386 #define ACTION_PTR(rule) \
387 (ipfw_insn *)((uint32_t *)((rule)->cmd) + ((rule)->act_ofs))
389 struct ipfw_ioc_rule {
390 uint16_t act_ofs; /* offset of action in 32-bit units */
391 uint16_t cmd_len; /* # of 32-bit words in cmd */
392 uint16_t rulenum; /* rule number */
393 uint8_t set; /* rule set (0..31) */
394 uint8_t usr_flags; /* IPFW_USR_F_ */
396 /* Rule set information */
397 uint32_t set_disable; /* disabled rule sets */
398 uint32_t static_count; /* # of static rules */
399 uint32_t static_len; /* total length of static rules */
402 uint64_t pcnt; /* Packet counter */
403 uint64_t bcnt; /* Byte counter */
404 uint32_t timestamp; /* tv_sec of last match */
406 uint8_t reserved[16];
408 ipfw_insn cmd[1]; /* storage for commands */
411 #define IPFW_USR_F_NORULE 0x01
413 #define IPFW_RULE_SIZE_MAX 255 /* unit: uint32_t */
415 #define IOC_RULESIZE(rule) \
416 (sizeof(struct ipfw_ioc_rule) + (rule)->cmd_len * 4 - 4)
418 struct ipfw_ioc_flowid {
419 uint16_t type; /* ETHERTYPE_ */
433 struct ipfw_ioc_state {
434 uint32_t expire; /* expire time */
435 uint64_t pcnt; /* packet match counter */
436 uint64_t bcnt; /* byte match counter */
438 uint16_t dyn_type; /* rule type */
439 uint16_t count; /* refcount */
444 int cpu; /* reserved */
446 struct ipfw_ioc_flowid id; /* (masked) flow id */
447 uint8_t reserved[16];
451 * Definitions for IP option names.
453 #define IP_FW_IPOPT_LSRR 0x01
454 #define IP_FW_IPOPT_SSRR 0x02
455 #define IP_FW_IPOPT_RR 0x04
456 #define IP_FW_IPOPT_TS 0x08
459 * Definitions for TCP option names.
461 #define IP_FW_TCPOPT_MSS 0x01
462 #define IP_FW_TCPOPT_WINDOW 0x02
463 #define IP_FW_TCPOPT_SACK 0x04
464 #define IP_FW_TCPOPT_TS 0x08
465 #define IP_FW_TCPOPT_CC 0x10
467 #define ICMP_REJECT_RST 0x100 /* fake ICMP code (send a TCP RST) */
470 * IP_FW_TBL_CREATE, tableid >= 0.
471 * IP_FW_TBL_FLUSH, tableid >= 0.
472 * IP_FW_TBL_FLUSH, tableid < 0, flush all tables.
473 * IP_FW_TBL_DESTROY, tableid >= 0.
474 * IP_FW_TBL_ZERO, tableid >= 0.
475 * IP_FW_TBL_ZERO, tableid < 0, zero all tables' counters.
477 struct ipfw_ioc_table {
481 struct ipfw_ioc_tblent {
482 struct sockaddr_in key;
483 struct sockaddr_in netmask;
490 * IP_FW_TBL_GET, tableid < 0, list of all tables.
492 struct ipfw_ioc_tbllist {
493 int tableid; /* MUST be the first field */
499 * IP_FW_TBL_GET, tableid >= 0, entries in the table.
500 * IP_FW_TBL_ADD, tableid >= 0, entcnt == 1.
501 * IP_FW_TBL_DEL, tableid >= 0, entcnt == 1.
503 struct ipfw_ioc_tblcont {
504 int tableid; /* MUST be the first field */
506 struct ipfw_ioc_tblent ent[1];
510 * IP_FW_TBL_EXPIRE, tableid < 0, expire all tables.
511 * IP_FW_TBL_EXPIRE, tableid >= 0.
513 struct ipfw_ioc_tblexp {
520 #endif /* _IPFW2_H */