x_tables.h revision e37d45ce390c2f5a7f1e64742b9100ecef0def54 
1#ifndef _X_TABLES_H
2#define _X_TABLES_H
3#include <linux/kernel.h>
4#include <linux/types.h>
5
6#define XT_FUNCTION_MAXNAMELEN 30
7#define XT_EXTENSION_MAXNAMELEN 29
8#define XT_TABLE_MAXNAMELEN 32
9
10struct xt_entry_match {
11	union {
12		struct {
13			__u16 match_size;
14
15			/* Used by userspace */
16			char name[XT_EXTENSION_MAXNAMELEN];
17			__u8 revision;
18		} user;
19		struct {
20			__u16 match_size;
21
22			/* Used inside the kernel */
23			struct xt_match *match;
24		} kernel;
25
26		/* Total length */
27		__u16 match_size;
28	} u;
29
30	unsigned char data[0];
31};
32
33struct xt_entry_target {
34	union {
35		struct {
36			__u16 target_size;
37
38			/* Used by userspace */
39			char name[XT_EXTENSION_MAXNAMELEN];
40			__u8 revision;
41		} user;
42		struct {
43			__u16 target_size;
44
45			/* Used inside the kernel */
46			struct xt_target *target;
47		} kernel;
48
49		/* Total length */
50		__u16 target_size;
51	} u;
52
53	unsigned char data[0];
54};
55
56#define XT_TARGET_INIT(__name, __size)					       \
57{									       \
58	.target.u.user = {						       \
59		.target_size	= XT_ALIGN(__size),			       \
60		.name		= __name,				       \
61	},								       \
62}
63
64struct xt_standard_target {
65	struct xt_entry_target target;
66	int verdict;
67};
68
69/* The argument to IPT_SO_GET_REVISION_*.  Returns highest revision
70 * kernel supports, if >= revision. */
71struct xt_get_revision {
72	char name[XT_EXTENSION_MAXNAMELEN];
73	__u8 revision;
74};
75
76/* CONTINUE verdict for targets */
77#define XT_CONTINUE 0xFFFFFFFF
78
79/* For standard target */
80#define XT_RETURN (-NF_REPEAT - 1)
81
82/* this is a dummy structure to find out the alignment requirement for a struct
83 * containing all the fundamental data types that are used in ipt_entry,
84 * ip6t_entry and arpt_entry.  This sucks, and it is a hack.  It will be my
85 * personal pleasure to remove it -HW
86 */
87struct _xt_align {
88	__u8 u8;
89	__u16 u16;
90	__u32 u32;
91	__u64 u64;
92};
93
94#define XT_ALIGN(s) __ALIGN_KERNEL((s), __alignof__(struct _xt_align))
95
96/* Standard return verdict, or do jump. */
97#define XT_STANDARD_TARGET ""
98/* Error verdict. */
99#define XT_ERROR_TARGET "ERROR"
100
101#define SET_COUNTER(c,b,p) do { (c).bcnt = (b); (c).pcnt = (p); } while(0)
102#define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0)
103
104struct xt_counters {
105	__u64 pcnt, bcnt;			/* Packet and byte counters */
106};
107
108/* The argument to IPT_SO_ADD_COUNTERS. */
109struct xt_counters_info {
110	/* Which table. */
111	char name[XT_TABLE_MAXNAMELEN];
112
113	unsigned int num_counters;
114
115	/* The counters (actually `number' of these). */
116	struct xt_counters counters[0];
117};
118
119#define XT_INV_PROTO		0x40	/* Invert the sense of PROTO. */
120
121/* fn returns 0 to continue iteration */
122#define XT_MATCH_ITERATE(type, e, fn, args...)			\
123({								\
124	unsigned int __i;					\
125	int __ret = 0;						\
126	struct xt_entry_match *__m;				\
127								\
128	for (__i = sizeof(type);				\
129	     __i < (e)->target_offset;				\
130	     __i += __m->u.match_size) {			\
131		__m = (void *)e + __i;				\
132								\
133		__ret = fn(__m , ## args);			\
134		if (__ret != 0)					\
135			break;					\
136	}							\
137	__ret;							\
138})
139
140/* fn returns 0 to continue iteration */
141#define XT_ENTRY_ITERATE_CONTINUE(type, entries, size, n, fn, args...) \
142({								\
143	unsigned int __i, __n;					\
144	int __ret = 0;						\
145	type *__entry;						\
146								\
147	for (__i = 0, __n = 0; __i < (size);			\
148	     __i += __entry->next_offset, __n++) { 		\
149		__entry = (void *)(entries) + __i;		\
150		if (__n < n)					\
151			continue;				\
152								\
153		__ret = fn(__entry , ## args);			\
154		if (__ret != 0)					\
155			break;					\
156	}							\
157	__ret;							\
158})
159
160/* fn returns 0 to continue iteration */
161#define XT_ENTRY_ITERATE(type, entries, size, fn, args...) \
162	XT_ENTRY_ITERATE_CONTINUE(type, entries, size, 0, fn, args)
163
164
165/* pos is normally a struct ipt_entry/ip6t_entry/etc. */
166#define xt_entry_foreach(pos, ehead, esize) \
167	for ((pos) = (typeof(pos))(ehead); \
168	     (pos) < (typeof(pos))((char *)(ehead) + (esize)); \
169	     (pos) = (typeof(pos))((char *)(pos) + (pos)->next_offset))
170
171/* can only be xt_entry_match, so no use of typeof here */
172#define xt_ematch_foreach(pos, entry) \
173	for ((pos) = (struct xt_entry_match *)entry->elems; \
174	     (pos) < (struct xt_entry_match *)((char *)(entry) + \
175	             (entry)->target_offset); \
176	     (pos) = (struct xt_entry_match *)((char *)(pos) + \
177	             (pos)->u.match_size))
178
179
180#endif /* _X_TABLES_H */
181