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 stongly inspired on 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/netfilter_bridge.h>
  16
  17 #define EBT_TABLE_MAXNAMELEN 32
  18 #define EBT_CHAIN_MAXNAMELEN EBT_TABLE_MAXNAMELEN
  19 #define EBT_FUNCTION_MAXNAMELEN EBT_TABLE_MAXNAMELEN
  20
  21 /* verdicts >0 are "branches" */
  22 #define EBT_ACCEPT   -1
  23 #define EBT_DROP     -2
  24 #define EBT_CONTINUE -3
  25 #define EBT_RETURN   -4
  26 #define NUM_STANDARD_TARGETS   4
  27 /* ebtables target modules store the verdict inside an int. We can
  28  * reclaim a part of this int for backwards compatible extensions.
  29  * The 4 lsb are more than enough to store the verdict. */
  30 #define EBT_VERDICT_BITS 0x0000000F
  31
  32 struct xt_match;
  33 struct xt_target;
  34
  35 struct ebt_counter {
  36         uint64_t pcnt;
  37         uint64_t bcnt;
  38 };
  39
  40 struct ebt_replace {
  41         char name[EBT_TABLE_MAXNAMELEN];
  42         unsigned int valid_hooks;
  43         /* nr of rules in the table */
  44         unsigned int nentries;
  45         /* total size of the entries */
  46         unsigned int entries_size;
  47         /* start of the chains */
  48         struct ebt_entries __user *hook_entry[NF_BR_NUMHOOKS];
  49         /* nr of counters userspace expects back */
  50         unsigned int num_counters;
  51         /* where the kernel will put the old counters */
  52         struct ebt_counter __user *counters;
  53         char __user *entries;
  54 };
  55
  56 struct ebt_replace_kernel {
  57         char name[EBT_TABLE_MAXNAMELEN];
  58         unsigned int valid_hooks;
  59         /* nr of rules in the table */
  60         unsigned int nentries;
  61         /* total size of the entries */
  62         unsigned int entries_size;
  63         /* start of the chains */
  64         struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
  65         /* nr of counters userspace expects back */
  66         unsigned int num_counters;
  67         /* where the kernel will put the old counters */
  68         struct ebt_counter *counters;
  69         char *entries;
  70 };
  71
  72 struct ebt_entries {
  73         /* this field is always set to zero
  74          * See EBT_ENTRY_OR_ENTRIES.
  75          * Must be same size as ebt_entry.bitmask */
  76         unsigned int distinguisher;
  77         /* the chain name */
  78         char name[EBT_CHAIN_MAXNAMELEN];
  79         /* counter offset for this chain */
  80         unsigned int counter_offset;
  81         /* one standard (accept, drop, return) per hook */
  82         int policy;
  83         /* nr. of entries */
  84         unsigned int nentries;
  85         /* entry list */
  86         char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
  87 };
  88
  89 /* used for the bitmask of struct ebt_entry */
  90
  91 /* This is a hack to make a difference between an ebt_entry struct and an
  92  * ebt_entries struct when traversing the entries from start to end.
  93  * Using this simplifies the code a lot, while still being able to use
  94  * ebt_entries.
  95  * Contrary, iptables doesn't use something like ebt_entries and therefore uses
  96  * different techniques for naming the policy and such. So, iptables doesn't
  97  * need a hack like this.
  98  */
  99 #define EBT_ENTRY_OR_ENTRIES 0x01
 100 /* these are the normal masks */
 101 #define EBT_NOPROTO 0x02
 102 #define EBT_802_3 0x04
 103 #define EBT_SOURCEMAC 0x08
 104 #define EBT_DESTMAC 0x10
 105 #define EBT_F_MASK (EBT_NOPROTO | EBT_802_3 | EBT_SOURCEMAC | EBT_DESTMAC \
 106    | EBT_ENTRY_OR_ENTRIES)
 107
 108 #define EBT_IPROTO 0x01
 109 #define EBT_IIN 0x02
 110 #define EBT_IOUT 0x04
 111 #define EBT_ISOURCE 0x8
 112 #define EBT_IDEST 0x10
 113 #define EBT_ILOGICALIN 0x20
 114 #define EBT_ILOGICALOUT 0x40
 115 #define EBT_INV_MASK (EBT_IPROTO | EBT_IIN | EBT_IOUT | EBT_ILOGICALIN \
 116    | EBT_ILOGICALOUT | EBT_ISOURCE | EBT_IDEST)
 117
 118 struct ebt_entry_match {
 119         union {
 120                 char name[EBT_FUNCTION_MAXNAMELEN];
 121                 struct xt_match *match;
 122         } u;
 123         /* size of data */
 124         unsigned int match_size;
 125         unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 126 };
 127
 128 struct ebt_entry_watcher {
 129         union {
 130                 char name[EBT_FUNCTION_MAXNAMELEN];
 131                 struct xt_target *watcher;
 132         } u;
 133         /* size of data */
 134         unsigned int watcher_size;
 135         unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 136 };
 137
 138 struct ebt_entry_target {
 139         union {
 140                 char name[EBT_FUNCTION_MAXNAMELEN];
 141                 struct xt_target *target;
 142         } u;
 143         /* size of data */
 144         unsigned int target_size;
 145         unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 146 };
 147
 148 #define EBT_STANDARD_TARGET "standard"
 149 struct ebt_standard_target {
 150         struct ebt_entry_target target;
 151         int verdict;
 152 };
 153
 154 /* one entry */
 155 struct ebt_entry {
 156         /* this needs to be the first field */
 157         unsigned int bitmask;
 158         unsigned int invflags;
 159         __be16 ethproto;
 160         /* the physical in-dev */
 161         char in[IFNAMSIZ];
 162         /* the logical in-dev */
 163         char logical_in[IFNAMSIZ];
 164         /* the physical out-dev */
 165         char out[IFNAMSIZ];
 166         /* the logical out-dev */
 167         char logical_out[IFNAMSIZ];
 168         unsigned char sourcemac[ETH_ALEN];
 169         unsigned char sourcemsk[ETH_ALEN];
 170         unsigned char destmac[ETH_ALEN];
 171         unsigned char destmsk[ETH_ALEN];
 172         /* sizeof ebt_entry + matches */
 173         unsigned int watchers_offset;
 174         /* sizeof ebt_entry + matches + watchers */
 175         unsigned int target_offset;
 176         /* sizeof ebt_entry + matches + watchers + target */
 177         unsigned int next_offset;
 178         unsigned char elems[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 179 };
 180
 181 /* {g,s}etsockopt numbers */
 182 #define EBT_BASE_CTL            128
 183
 184 #define EBT_SO_SET_ENTRIES      (EBT_BASE_CTL)
 185 #define EBT_SO_SET_COUNTERS     (EBT_SO_SET_ENTRIES+1)
 186 #define EBT_SO_SET_MAX          (EBT_SO_SET_COUNTERS+1)
 187
 188 #define EBT_SO_GET_INFO         (EBT_BASE_CTL)
 189 #define EBT_SO_GET_ENTRIES      (EBT_SO_GET_INFO+1)
 190 #define EBT_SO_GET_INIT_INFO    (EBT_SO_GET_ENTRIES+1)
 191 #define EBT_SO_GET_INIT_ENTRIES (EBT_SO_GET_INIT_INFO+1)
 192 #define EBT_SO_GET_MAX          (EBT_SO_GET_INIT_ENTRIES+1)
 193
 194
 195 /* blatently stolen from ip_tables.h
 196  * fn returns 0 to continue iteration */
 197 #define EBT_MATCH_ITERATE(e, fn, args...)                   \
 198 ({                                                          \
 199         unsigned int __i;                                   \
 200         int __ret = 0;                                      \
 201         struct ebt_entry_match *__match;                    \
 202                                                             \
 203         for (__i = sizeof(struct ebt_entry);                \
 204              __i < (e)->watchers_offset;                    \
 205              __i += __match->match_size +                   \
 206              sizeof(struct ebt_entry_match)) {              \
 207                 __match = (void *)(e) + __i;                \
 208                                                             \
 209                 __ret = fn(__match , ## args);              \
 210                 if (__ret != 0)                             \
 211                         break;                              \
 212         }                                                   \
 213         if (__ret == 0) {                                   \
 214                 if (__i != (e)->watchers_offset)            \
 215                         __ret = -EINVAL;                    \
 216         }                                                   \
 217         __ret;                                              \
 218 })
 219
 220 #define EBT_WATCHER_ITERATE(e, fn, args...)                 \
 221 ({                                                          \
 222         unsigned int __i;                                   \
 223         int __ret = 0;                                      \
 224         struct ebt_entry_watcher *__watcher;                \
 225                                                             \
 226         for (__i = e->watchers_offset;                      \
 227              __i < (e)->target_offset;                      \
 228              __i += __watcher->watcher_size +               \
 229              sizeof(struct ebt_entry_watcher)) {            \
 230                 __watcher = (void *)(e) + __i;              \
 231                                                             \
 232                 __ret = fn(__watcher , ## args);            \
 233                 if (__ret != 0)                             \
 234                         break;                              \
 235         }                                                   \
 236         if (__ret == 0) {                                   \
 237                 if (__i != (e)->target_offset)              \
 238                         __ret = -EINVAL;                    \
 239         }                                                   \
 240         __ret;                                              \
 241 })
 242
 243 #define EBT_ENTRY_ITERATE(entries, size, fn, args...)       \
 244 ({                                                          \
 245         unsigned int __i;                                   \
 246         int __ret = 0;                                      \
 247         struct ebt_entry *__entry;                          \
 248                                                             \
 249         for (__i = 0; __i < (size);) {                      \
 250                 __entry = (void *)(entries) + __i;          \
 251                 __ret = fn(__entry , ## args);              \
 252                 if (__ret != 0)                             \
 253                         break;                              \
 254                 if (__entry->bitmask != 0)                  \
 255                         __i += __entry->next_offset;        \
 256                 else                                        \
 257                         __i += sizeof(struct ebt_entries);  \
 258         }                                                   \
 259         if (__ret == 0) {                                   \
 260                 if (__i != (size))                          \
 261                         __ret = -EINVAL;                    \
 262         }                                                   \
 263         __ret;                                              \
 264 })
 265
 266 #endif /* _UAPI__LINUX_BRIDGE_EFF_H */