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/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
* ebtables
*
* Authors:
* Bart De Schuymer <bdschuym@pandora.be>
*
* ebtables.c,v 2.0, April, 2002
*
* This code is strongly inspired by the iptables code which is
* Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
*/
#ifndef __LINUX_BRIDGE_EFF_H
#define __LINUX_BRIDGE_EFF_H
#include <linux/types.h>
#include <linux/if.h>
#include <linux/netfilter_bridge.h>
#define EBT_TABLE_MAXNAMELEN 32
#define EBT_CHAIN_MAXNAMELEN EBT_TABLE_MAXNAMELEN
#define EBT_FUNCTION_MAXNAMELEN EBT_TABLE_MAXNAMELEN
#define EBT_EXTENSION_MAXNAMELEN 31
/* verdicts >0 are "branches" */
#define EBT_ACCEPT -1
#define EBT_DROP -2
#define EBT_CONTINUE -3
#define EBT_RETURN -4
#define NUM_STANDARD_TARGETS 4
/* ebtables target modules store the verdict inside an int. We can
* reclaim a part of this int for backwards compatible extensions.
* The 4 lsb are more than enough to store the verdict. */
#define EBT_VERDICT_BITS 0x0000000F
struct xt_match;
struct xt_target;
struct ebt_counter {
__u64 pcnt;
__u64 bcnt;
};
struct ebt_replace {
char name[EBT_TABLE_MAXNAMELEN];
unsigned int valid_hooks;
/* nr of rules in the table */
unsigned int nentries;
/* total size of the entries */
unsigned int entries_size;
/* start of the chains */
struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
/* nr of counters userspace expects back */
unsigned int num_counters;
/* where the kernel will put the old counters */
struct ebt_counter *counters;
char *entries;
};
struct ebt_replace_kernel {
char name[EBT_TABLE_MAXNAMELEN];
unsigned int valid_hooks;
/* nr of rules in the table */
unsigned int nentries;
/* total size of the entries */
unsigned int entries_size;
/* start of the chains */
struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
/* nr of counters userspace expects back */
unsigned int num_counters;
/* where the kernel will put the old counters */
struct ebt_counter *counters;
char *entries;
};
struct ebt_entries {
/* this field is always set to zero
* See EBT_ENTRY_OR_ENTRIES.
* Must be same size as ebt_entry.bitmask */
unsigned int distinguisher;
/* the chain name */
char name[EBT_CHAIN_MAXNAMELEN];
/* counter offset for this chain */
unsigned int counter_offset;
/* one standard (accept, drop, return) per hook */
int policy;
/* nr. of entries */
unsigned int nentries;
/* entry list */
char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
};
/* used for the bitmask of struct ebt_entry */
/* This is a hack to make a difference between an ebt_entry struct and an
* ebt_entries struct when traversing the entries from start to end.
* Using this simplifies the code a lot, while still being able to use
* ebt_entries.
* Contrary, iptables doesn't use something like ebt_entries and therefore uses
* different techniques for naming the policy and such. So, iptables doesn't
* need a hack like this.
*/
#define EBT_ENTRY_OR_ENTRIES 0x01
/* these are the normal masks */
#define EBT_NOPROTO 0x02
#define EBT_802_3 0x04
#define EBT_SOURCEMAC 0x08
#define EBT_DESTMAC 0x10
#define EBT_F_MASK (EBT_NOPROTO | EBT_802_3 | EBT_SOURCEMAC | EBT_DESTMAC \
| EBT_ENTRY_OR_ENTRIES)
#define EBT_IPROTO 0x01
#define EBT_IIN 0x02
#define EBT_IOUT 0x04
#define EBT_ISOURCE 0x8
#define EBT_IDEST 0x10
#define EBT_ILOGICALIN 0x20
#define EBT_ILOGICALOUT 0x40
#define EBT_INV_MASK (EBT_IPROTO | EBT_IIN | EBT_IOUT | EBT_ILOGICALIN \
| EBT_ILOGICALOUT | EBT_ISOURCE | EBT_IDEST)
struct ebt_entry_match {
union {
struct {
char name[EBT_EXTENSION_MAXNAMELEN];
uint8_t revision;
};
struct xt_match *match;
} u;
/* size of data */
unsigned int match_size;
unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
};
struct ebt_entry_watcher {
union {
struct {
char name[EBT_EXTENSION_MAXNAMELEN];
uint8_t revision;
};
struct xt_target *watcher;
} u;
/* size of data */
unsigned int watcher_size;
unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
};
struct ebt_entry_target {
union {
struct {
char name[EBT_EXTENSION_MAXNAMELEN];
uint8_t revision;
};
struct xt_target *target;
} u;
/* size of data */
unsigned int target_size;
unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
};
#define EBT_STANDARD_TARGET "standard"
struct ebt_standard_target {
struct ebt_entry_target target;
int verdict;
};
/* one entry */
struct ebt_entry {
/* this needs to be the first field */
unsigned int bitmask;
unsigned int invflags;
__be16 ethproto;
/* the physical in-dev */
char in[IFNAMSIZ];
/* the logical in-dev */
char logical_in[IFNAMSIZ];
/* the physical out-dev */
char out[IFNAMSIZ];
/* the logical out-dev */
char logical_out[IFNAMSIZ];
unsigned char sourcemac[ETH_ALEN];
unsigned char sourcemsk[ETH_ALEN];
unsigned char destmac[ETH_ALEN];
unsigned char destmsk[ETH_ALEN];
/* sizeof ebt_entry + matches */
unsigned int watchers_offset;
/* sizeof ebt_entry + matches + watchers */
unsigned int target_offset;
/* sizeof ebt_entry + matches + watchers + target */
unsigned int next_offset;
unsigned char elems[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
};
static __inline__ struct ebt_entry_target *
ebt_get_target(struct ebt_entry *e)
{
return (void *)e + e->target_offset;
}
/* {g,s}etsockopt numbers */
#define EBT_BASE_CTL 128
#define EBT_SO_SET_ENTRIES (EBT_BASE_CTL)
#define EBT_SO_SET_COUNTERS (EBT_SO_SET_ENTRIES+1)
#define EBT_SO_SET_MAX (EBT_SO_SET_COUNTERS+1)
#define EBT_SO_GET_INFO (EBT_BASE_CTL)
#define EBT_SO_GET_ENTRIES (EBT_SO_GET_INFO+1)
#define EBT_SO_GET_INIT_INFO (EBT_SO_GET_ENTRIES+1)
#define EBT_SO_GET_INIT_ENTRIES (EBT_SO_GET_INIT_INFO+1)
#define EBT_SO_GET_MAX (EBT_SO_GET_INIT_ENTRIES+1)
/* blatently stolen from ip_tables.h
* fn returns 0 to continue iteration */
#define EBT_MATCH_ITERATE(e, fn, args...) \
({ \
unsigned int __i; \
int __ret = 0; \
struct ebt_entry_match *__match; \
\
for (__i = sizeof(struct ebt_entry); \
__i < (e)->watchers_offset; \
__i += __match->match_size + \
sizeof(struct ebt_entry_match)) { \
__match = (void *)(e) + __i; \
\
__ret = fn(__match , ## args); \
if (__ret != 0) \
break; \
} \
if (__ret == 0) { \
if (__i != (e)->watchers_offset) \
__ret = -EINVAL; \
} \
__ret; \
})
#define EBT_WATCHER_ITERATE(e, fn, args...) \
({ \
unsigned int __i; \
int __ret = 0; \
struct ebt_entry_watcher *__watcher; \
\
for (__i = e->watchers_offset; \
__i < (e)->target_offset; \
__i += __watcher->watcher_size + \
sizeof(struct ebt_entry_watcher)) { \
__watcher = (void *)(e) + __i; \
\
__ret = fn(__watcher , ## args); \
if (__ret != 0) \
break; \
} \
if (__ret == 0) { \
if (__i != (e)->target_offset) \
__ret = -EINVAL; \
} \
__ret; \
})
#define EBT_ENTRY_ITERATE(entries, size, fn, args...) \
({ \
unsigned int __i; \
int __ret = 0; \
struct ebt_entry *__entry; \
\
for (__i = 0; __i < (size);) { \
__entry = (void *)(entries) + __i; \
__ret = fn(__entry , ## args); \
if (__ret != 0) \
break; \
if (__entry->bitmask != 0) \
__i += __entry->next_offset; \
else \
__i += sizeof(struct ebt_entries); \
} \
if (__ret == 0) { \
if (__i != (size)) \
__ret = -EINVAL; \
} \
__ret; \
})
#endif /* __LINUX_BRIDGE_EFF_H */
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