LXR linux/include/linux/netfilter

   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#ifndef __LINUX_BRIDGE_EFF_H
  13#define __LINUX_BRIDGE_EFF_H
  14
  15#include <linux/if.h>
  16#include <linux/if_ether.h>
  17#include <uapi/linux/netfilter_bridge/ebtables.h>
  18
  19/* return values for match() functions */
  20#define EBT_MATCH 0
  21#define EBT_NOMATCH 1
  22
  23struct ebt_match {
  24        struct list_head list;
  25        const char name[EBT_FUNCTION_MAXNAMELEN];
  26        bool (*match)(const struct sk_buff *skb, const struct net_device *in,
  27                const struct net_device *out, const struct xt_match *match,
  28                const void *matchinfo, int offset, unsigned int protoff,
  29                bool *hotdrop);
  30        bool (*checkentry)(const char *table, const void *entry,
  31                const struct xt_match *match, void *matchinfo,
  32                unsigned int hook_mask);
  33        void (*destroy)(const struct xt_match *match, void *matchinfo);
  34        unsigned int matchsize;
  35        u_int8_t revision;
  36        u_int8_t family;
  37        struct module *me;
  38};
  39
  40struct ebt_watcher {
  41        struct list_head list;
  42        const char name[EBT_FUNCTION_MAXNAMELEN];
  43        unsigned int (*target)(struct sk_buff *skb,
  44                const struct net_device *in, const struct net_device *out,
  45                unsigned int hook_num, const struct xt_target *target,
  46                const void *targinfo);
  47        bool (*checkentry)(const char *table, const void *entry,
  48                const struct xt_target *target, void *targinfo,
  49                unsigned int hook_mask);
  50        void (*destroy)(const struct xt_target *target, void *targinfo);
  51        unsigned int targetsize;
  52        u_int8_t revision;
  53        u_int8_t family;
  54        struct module *me;
  55};
  56
  57struct ebt_target {
  58        struct list_head list;
  59        const char name[EBT_FUNCTION_MAXNAMELEN];
  60        /* returns one of the standard EBT_* verdicts */
  61        unsigned int (*target)(struct sk_buff *skb,
  62                const struct net_device *in, const struct net_device *out,
  63                unsigned int hook_num, const struct xt_target *target,
  64                const void *targinfo);
  65        bool (*checkentry)(const char *table, const void *entry,
  66                const struct xt_target *target, void *targinfo,
  67                unsigned int hook_mask);
  68        void (*destroy)(const struct xt_target *target, void *targinfo);
  69        unsigned int targetsize;
  70        u_int8_t revision;
  71        u_int8_t family;
  72        struct module *me;
  73};
  74
  75/* used for jumping from and into user defined chains (udc) */
  76struct ebt_chainstack {
  77        struct ebt_entries *chaininfo; /* pointer to chain data */
  78        struct ebt_entry *e; /* pointer to entry data */
  79        unsigned int n; /* n'th entry */
  80};
  81
  82struct ebt_table_info {
  83        /* total size of the entries */
  84        unsigned int entries_size;
  85        unsigned int nentries;
  86        /* pointers to the start of the chains */
  87        struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
  88        /* room to maintain the stack used for jumping from and into udc */
  89        struct ebt_chainstack **chainstack;
  90        char *entries;
  91        struct ebt_counter counters[0] ____cacheline_aligned;
  92};
  93
  94struct ebt_table {
  95        struct list_head list;
  96        char name[EBT_TABLE_MAXNAMELEN];
  97        struct ebt_replace_kernel *table;
  98        unsigned int valid_hooks;
  99        rwlock_t lock;
 100        /* e.g. could be the table explicitly only allows certain
 101         * matches, targets, ... 0 == let it in */
 102        int (*check)(const struct ebt_table_info *info,
 103           unsigned int valid_hooks);
 104        /* the data used by the kernel */
 105        struct ebt_table_info *private;
 106        struct module *me;
 107};
 108
 109#define EBT_ALIGN(s) (((s) + (__alignof__(struct _xt_align)-1)) & \
 110                     ~(__alignof__(struct _xt_align)-1))
 111extern struct ebt_table *ebt_register_table(struct net *net,
 112                                            const struct ebt_table *table);
 113extern void ebt_unregister_table(struct net *net, struct ebt_table *table);
 114extern unsigned int ebt_do_table(struct sk_buff *skb,
 115                                 const struct nf_hook_state *state,
 116                                 struct ebt_table *table);
 117
 118/* True if the hook mask denotes that the rule is in a base chain,
 119 * used in the check() functions */
 120#define BASE_CHAIN (par->hook_mask & (1 << NF_BR_NUMHOOKS))
 121/* Clear the bit in the hook mask that tells if the rule is on a base chain */
 122#define CLEAR_BASE_CHAIN_BIT (par->hook_mask &= ~(1 << NF_BR_NUMHOOKS))
 123/* True if the target is not a standard target */
 124#define INVALID_TARGET (info->target < -NUM_STANDARD_TARGETS || info->target >= 0)
 125
 126#endif
 127