kernel/include/uapi/linux/netfilter/x_tables.h

   1 #ifndef _UAPI_X_TABLES_H
   2 #define _UAPI_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
  10 struct 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
  33 struct 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
  64 struct xt_standard_target {
  65         struct xt_entry_target target;
  66         int verdict;
  67 };
  68
  69 struct xt_error_target {
  70         struct xt_entry_target target;
  71         char errorname[XT_FUNCTION_MAXNAMELEN];
  72 };
  73
  74 /* The argument to IPT_SO_GET_REVISION_*.  Returns highest revision
  75  * kernel supports, if >= revision. */
  76 struct xt_get_revision {
  77         char name[XT_EXTENSION_MAXNAMELEN];
  78         __u8 revision;
  79 };
  80
  81 /* CONTINUE verdict for targets */
  82 #define XT_CONTINUE 0xFFFFFFFF
  83
  84 /* For standard target */
  85 #define XT_RETURN (-NF_REPEAT - 1)
  86
  87 /* this is a dummy structure to find out the alignment requirement for a struct
  88  * containing all the fundamental data types that are used in ipt_entry,
  89  * ip6t_entry and arpt_entry.  This sucks, and it is a hack.  It will be my
  90  * personal pleasure to remove it -HW
  91  */
  92 struct _xt_align {
  93         __u8 u8;
  94         __u16 u16;
  95         __u32 u32;
  96         __u64 u64;
  97 };
  98
  99 #define XT_ALIGN(s) __ALIGN_KERNEL((s), __alignof__(struct _xt_align))
 100
 101 /* Standard return verdict, or do jump. */
 102 #define XT_STANDARD_TARGET ""
 103 /* Error verdict. */
 104 #define XT_ERROR_TARGET "ERROR"
 105
 106 #define SET_COUNTER(c,b,p) do { (c).bcnt = (b); (c).pcnt = (p); } while(0)
 107 #define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0)
 108
 109 struct xt_counters {
 110         __u64 pcnt, bcnt;                       /* Packet and byte counters */
 111 };
 112
 113 /* The argument to IPT_SO_ADD_COUNTERS. */
 114 struct xt_counters_info {
 115         /* Which table. */
 116         char name[XT_TABLE_MAXNAMELEN];
 117
 118         unsigned int num_counters;
 119
 120         /* The counters (actually `number' of these). */
 121         struct xt_counters counters[0];
 122 };
 123
 124 #define XT_INV_PROTO            0x40    /* Invert the sense of PROTO. */
 125
 126 #ifndef __KERNEL__
 127 /* fn returns 0 to continue iteration */
 128 #define XT_MATCH_ITERATE(type, e, fn, args...)                  \
 129 ({                                                              \
 130         unsigned int __i;                                       \
 131         int __ret = 0;                                          \
 132         struct xt_entry_match *__m;                             \
 133                                                                 \
 134         for (__i = sizeof(type);                                \
 135              __i < (e)->target_offset;                          \
 136              __i += __m->u.match_size) {                        \
 137                 __m = (void *)e + __i;                          \
 138                                                                 \
 139                 __ret = fn(__m , ## args);                      \
 140                 if (__ret != 0)                                 \
 141                         break;                                  \
 142         }                                                       \
 143         __ret;                                                  \
 144 })
 145
 146 /* fn returns 0 to continue iteration */
 147 #define XT_ENTRY_ITERATE_CONTINUE(type, entries, size, n, fn, args...) \
 148 ({                                                              \
 149         unsigned int __i, __n;                                  \
 150         int __ret = 0;                                          \
 151         type *__entry;                                          \
 152                                                                 \
 153         for (__i = 0, __n = 0; __i < (size);                    \
 154              __i += __entry->next_offset, __n++) {              \
 155                 __entry = (void *)(entries) + __i;              \
 156                 if (__n < n)                                    \
 157                         continue;                               \
 158                                                                 \
 159                 __ret = fn(__entry , ## args);                  \
 160                 if (__ret != 0)                                 \
 161                         break;                                  \
 162         }                                                       \
 163         __ret;                                                  \
 164 })
 165
 166 /* fn returns 0 to continue iteration */
 167 #define XT_ENTRY_ITERATE(type, entries, size, fn, args...) \
 168         XT_ENTRY_ITERATE_CONTINUE(type, entries, size, 0, fn, args)
 169
 170 #endif /* !__KERNEL__ */
 171
 172 /* pos is normally a struct ipt_entry/ip6t_entry/etc. */
 173 #define xt_entry_foreach(pos, ehead, esize) \
 174         for ((pos) = (typeof(pos))(ehead); \
 175              (pos) < (typeof(pos))((char *)(ehead) + (esize)); \
 176              (pos) = (typeof(pos))((char *)(pos) + (pos)->next_offset))
 177
 178 /* can only be xt_entry_match, so no use of typeof here */
 179 #define xt_ematch_foreach(pos, entry) \
 180         for ((pos) = (struct xt_entry_match *)entry->elems; \
 181              (pos) < (struct xt_entry_match *)((char *)(entry) + \
 182                      (entry)->target_offset); \
 183              (pos) = (struct xt_entry_match *)((char *)(pos) + \
 184                      (pos)->u.match_size))
 185
 186
 187 #endif /* _UAPI_X_TABLES_H */