include/uapi/linux/netfilter_bridge/ebtables.h

   1 /*
   2  *  ebtables
   3  *
   4  *      Authors:
   5  *      Bart De Schuymer                <bdschuym@pandora.be>
   6  *
   7  *  ebtables.c,v 2.0, April, 2002
   8  *
   9  *  This code is strongly inspired by the iptables code which is
  10  *  Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
  11  */
  12
  13 #ifndef _UAPI__LINUX_BRIDGE_EFF_H
  14 #define _UAPI__LINUX_BRIDGE_EFF_H
  15 #include <linux/types.h>
  16 #include <linux/if.h>
  17 #include <linux/netfilter_bridge.h>
  18
  19 #define EBT_TABLE_MAXNAMELEN 32
  20 #define EBT_CHAIN_MAXNAMELEN EBT_TABLE_MAXNAMELEN
  21 #define EBT_FUNCTION_MAXNAMELEN EBT_TABLE_MAXNAMELEN
  22
  23 /* verdicts >0 are "branches" */
  24 #define EBT_ACCEPT   -1
  25 #define EBT_DROP     -2
  26 #define EBT_CONTINUE -3
  27 #define EBT_RETURN   -4
  28 #define NUM_STANDARD_TARGETS   4
  29 /* ebtables target modules store the verdict inside an int. We can
  30  * reclaim a part of this int for backwards compatible extensions.
  31  * The 4 lsb are more than enough to store the verdict. */
  32 #define EBT_VERDICT_BITS 0x0000000F
  33
  34 struct xt_match;
  35 struct xt_target;
  36
  37 struct ebt_counter {
  38         __u64 pcnt;
  39         __u64 bcnt;
  40 };
  41
  42 struct ebt_replace {
  43         char name[EBT_TABLE_MAXNAMELEN];
  44         unsigned int valid_hooks;
  45         /* nr of rules in the table */
  46         unsigned int nentries;
  47         /* total size of the entries */
  48         unsigned int entries_size;
  49         /* start of the chains */
  50         struct ebt_entries __user *hook_entry[NF_BR_NUMHOOKS];
  51         /* nr of counters userspace expects back */
  52         unsigned int num_counters;
  53         /* where the kernel will put the old counters */
  54         struct ebt_counter __user *counters;
  55         char __user *entries;
  56 };
  57
  58 struct ebt_replace_kernel {
  59         char name[EBT_TABLE_MAXNAMELEN];
  60         unsigned int valid_hooks;
  61         /* nr of rules in the table */
  62         unsigned int nentries;
  63         /* total size of the entries */
  64         unsigned int entries_size;
  65         /* start of the chains */
  66         struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
  67         /* nr of counters userspace expects back */
  68         unsigned int num_counters;
  69         /* where the kernel will put the old counters */
  70         struct ebt_counter *counters;
  71         char *entries;
  72 };
  73
  74 struct ebt_entries {
  75         /* this field is always set to zero
  76          * See EBT_ENTRY_OR_ENTRIES.
  77          * Must be same size as ebt_entry.bitmask */
  78         unsigned int distinguisher;
  79         /* the chain name */
  80         char name[EBT_CHAIN_MAXNAMELEN];
  81         /* counter offset for this chain */
  82         unsigned int counter_offset;
  83         /* one standard (accept, drop, return) per hook */
  84         int policy;
  85         /* nr. of entries */
  86         unsigned int nentries;
  87         /* entry list */
  88         char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
  89 };
  90
  91 /* used for the bitmask of struct ebt_entry */
  92
  93 /* This is a hack to make a difference between an ebt_entry struct and an
  94  * ebt_entries struct when traversing the entries from start to end.
  95  * Using this simplifies the code a lot, while still being able to use
  96  * ebt_entries.
  97  * Contrary, iptables doesn't use something like ebt_entries and therefore uses
  98  * different techniques for naming the policy and such. So, iptables doesn't
  99  * need a hack like this.
 100  */
 101 #define EBT_ENTRY_OR_ENTRIES 0x01
 102 /* these are the normal masks */
 103 #define EBT_NOPROTO 0x02
 104 #define EBT_802_3 0x04
 105 #define EBT_SOURCEMAC 0x08
 106 #define EBT_DESTMAC 0x10
 107 #define EBT_F_MASK (EBT_NOPROTO | EBT_802_3 | EBT_SOURCEMAC | EBT_DESTMAC \
 108    | EBT_ENTRY_OR_ENTRIES)
 109
 110 #define EBT_IPROTO 0x01
 111 #define EBT_IIN 0x02
 112 #define EBT_IOUT 0x04
 113 #define EBT_ISOURCE 0x8
 114 #define EBT_IDEST 0x10
 115 #define EBT_ILOGICALIN 0x20
 116 #define EBT_ILOGICALOUT 0x40
 117 #define EBT_INV_MASK (EBT_IPROTO | EBT_IIN | EBT_IOUT | EBT_ILOGICALIN \
 118    | EBT_ILOGICALOUT | EBT_ISOURCE | EBT_IDEST)
 119
 120 struct ebt_entry_match {
 121         union {
 122                 char name[EBT_FUNCTION_MAXNAMELEN];
 123                 struct xt_match *match;
 124         } u;
 125         /* size of data */
 126         unsigned int match_size;
 127         unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 128 };
 129
 130 struct ebt_entry_watcher {
 131         union {
 132                 char name[EBT_FUNCTION_MAXNAMELEN];
 133                 struct xt_target *watcher;
 134         } u;
 135         /* size of data */
 136         unsigned int watcher_size;
 137         unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 138 };
 139
 140 struct ebt_entry_target {
 141         union {
 142                 char name[EBT_FUNCTION_MAXNAMELEN];
 143                 struct xt_target *target;
 144         } u;
 145         /* size of data */
 146         unsigned int target_size;
 147         unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 148 };
 149
 150 #define EBT_STANDARD_TARGET "standard"
 151 struct ebt_standard_target {
 152         struct ebt_entry_target target;
 153         int verdict;
 154 };
 155
 156 /* one entry */
 157 struct ebt_entry {
 158         /* this needs to be the first field */
 159         unsigned int bitmask;
 160         unsigned int invflags;
 161         __be16 ethproto;
 162         /* the physical in-dev */
 163         char in[IFNAMSIZ];
 164         /* the logical in-dev */
 165         char logical_in[IFNAMSIZ];
 166         /* the physical out-dev */
 167         char out[IFNAMSIZ];
 168         /* the logical out-dev */
 169         char logical_out[IFNAMSIZ];
 170         unsigned char sourcemac[ETH_ALEN];
 171         unsigned char sourcemsk[ETH_ALEN];
 172         unsigned char destmac[ETH_ALEN];
 173         unsigned char destmsk[ETH_ALEN];
 174         /* sizeof ebt_entry + matches */
 175         unsigned int watchers_offset;
 176         /* sizeof ebt_entry + matches + watchers */
 177         unsigned int target_offset;
 178         /* sizeof ebt_entry + matches + watchers + target */
 179         unsigned int next_offset;
 180         unsigned char elems[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 181 };
 182
 183 /* {g,s}etsockopt numbers */
 184 #define EBT_BASE_CTL            128
 185
 186 #define EBT_SO_SET_ENTRIES      (EBT_BASE_CTL)
 187 #define EBT_SO_SET_COUNTERS     (EBT_SO_SET_ENTRIES+1)
 188 #define EBT_SO_SET_MAX          (EBT_SO_SET_COUNTERS+1)
 189
 190 #define EBT_SO_GET_INFO         (EBT_BASE_CTL)
 191 #define EBT_SO_GET_ENTRIES      (EBT_SO_GET_INFO+1)
 192 #define EBT_SO_GET_INIT_INFO    (EBT_SO_GET_ENTRIES+1)
 193 #define EBT_SO_GET_INIT_ENTRIES (EBT_SO_GET_INIT_INFO+1)
 194 #define EBT_SO_GET_MAX          (EBT_SO_GET_INIT_ENTRIES+1)
 195
 196
 197 /* blatently stolen from ip_tables.h
 198  * fn returns 0 to continue iteration */
 199 #define EBT_MATCH_ITERATE(e, fn, args...)                   \
 200 ({                                                          \
 201         unsigned int __i;                                   \
 202         int __ret = 0;                                      \
 203         struct ebt_entry_match *__match;                    \
 204                                                             \
 205         for (__i = sizeof(struct ebt_entry);                \
 206              __i < (e)->watchers_offset;                    \
 207              __i += __match->match_size +                   \
 208              sizeof(struct ebt_entry_match)) {              \
 209                 __match = (void *)(e) + __i;                \
 210                                                             \
 211                 __ret = fn(__match , ## args);              \
 212                 if (__ret != 0)                             \
 213                         break;                              \
 214         }                                                   \
 215         if (__ret == 0) {                                   \
 216                 if (__i != (e)->watchers_offset)            \
 217                         __ret = -EINVAL;                    \
 218         }                                                   \
 219         __ret;                                              \
 220 })
 221
 222 #define EBT_WATCHER_ITERATE(e, fn, args...)                 \
 223 ({                                                          \
 224         unsigned int __i;                                   \
 225         int __ret = 0;                                      \
 226         struct ebt_entry_watcher *__watcher;                \
 227                                                             \
 228         for (__i = e->watchers_offset;                      \
 229              __i < (e)->target_offset;                      \
 230              __i += __watcher->watcher_size +               \
 231              sizeof(struct ebt_entry_watcher)) {            \
 232                 __watcher = (void *)(e) + __i;              \
 233                                                             \
 234                 __ret = fn(__watcher , ## args);            \
 235                 if (__ret != 0)                             \
 236                         break;                              \
 237         }                                                   \
 238         if (__ret == 0) {                                   \
 239                 if (__i != (e)->target_offset)              \
 240                         __ret = -EINVAL;                    \
 241         }                                                   \
 242         __ret;                                              \
 243 })
 244
 245 #define EBT_ENTRY_ITERATE(entries, size, fn, args...)       \
 246 ({                                                          \
 247         unsigned int __i;                                   \
 248         int __ret = 0;                                      \
 249         struct ebt_entry *__entry;                          \
 250                                                             \
 251         for (__i = 0; __i < (size);) {                      \
 252                 __entry = (void *)(entries) + __i;          \
 253                 __ret = fn(__entry , ## args);              \
 254                 if (__ret != 0)                             \
 255                         break;                              \
 256                 if (__entry->bitmask != 0)                  \
 257                         __i += __entry->next_offset;        \
 258                 else                                        \
 259                         __i += sizeof(struct ebt_entries);  \
 260         }                                                   \
 261         if (__ret == 0) {                                   \
 262                 if (__i != (size))                          \
 263                         __ret = -EINVAL;                    \
 264         }                                                   \
 265         __ret;                                              \
 266 })
 267
 268 #endif /* _UAPI__LINUX_BRIDGE_EFF_H */