userspace/ebtables2/include/ebtables_u.h

/*
 * $Id: ebtables.c,v 1.03 2002/01/19
 *
 * Copyright (C) 2001-2002 Bart De Schuymer
 *
 *  This code is stongly inspired on the iptables code which is
 *  Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef EBTABLES_U_H
#define EBTABLES_U_H
#include <netinet/in.h>
#include <linux/netfilter_bridge/ebtables.h>

struct ebt_u_entries
{
	int policy;
	unsigned int nentries;
	// counter offset for this chain
	unsigned int counter_offset;
	// used for udc
	unsigned int hook_mask;
	char name[EBT_CHAIN_MAXNAMELEN];
	struct ebt_u_entry *entries;
};

struct ebt_u_chain_list
{
	struct ebt_u_entries *udc;
	struct ebt_u_chain_list *next;
	// this is only used internally, in communication.c
	char *kernel_start;
};

struct ebt_u_replace
{
	char name[EBT_TABLE_MAXNAMELEN];
	unsigned int valid_hooks;
	// nr of rules in the table
	unsigned int nentries;
	struct ebt_u_entries *hook_entry[NF_BR_NUMHOOKS];
	// user defined chains (udc) list
	struct ebt_u_chain_list *udc;
	// nr of counters userspace expects back
	unsigned int num_counters;
	// where the kernel will put the old counters
	struct ebt_counter *counters;
	// can be used e.g. to know if a standard option
	// has been specified twice
	unsigned int flags;
	// we stick the specified command (e.g. -A) in here
	char command;
	// here we stick the hook to do our thing on (can be -1 if unspecified)
	int selected_hook;
	// used for the atomic option
	char *filename;
	// tells what happened to the old rules
	unsigned short *counterchanges;
};

struct ebt_u_table
{
	char name[EBT_TABLE_MAXNAMELEN];
	void (*check)(struct ebt_u_replace *repl);
	void (*help)(char **);
	struct ebt_u_table *next;
};

struct ebt_u_match_list
{
	struct ebt_u_match_list *next;
	struct ebt_entry_match *m;
};

struct ebt_u_watcher_list
{
	struct ebt_u_watcher_list *next;
	struct ebt_entry_watcher *w;
};

struct ebt_u_entry
{
	unsigned int bitmask;
	unsigned int invflags;
	uint16_t ethproto;
	char in[IFNAMSIZ];
	char logical_in[IFNAMSIZ];
	char out[IFNAMSIZ];
	char logical_out[IFNAMSIZ];
	unsigned char sourcemac[ETH_ALEN];
	unsigned char sourcemsk[ETH_ALEN];
	unsigned char destmac[ETH_ALEN];
	unsigned char destmsk[ETH_ALEN];
	struct ebt_u_match_list *m_list;
	struct ebt_u_watcher_list *w_list;
	struct ebt_entry_target *t;
	struct ebt_u_entry *next;
};

struct ebt_u_match
{
	char name[EBT_FUNCTION_MAXNAMELEN];
	// size of the real match data
	unsigned int size;
	void (*help)(void);
	void (*init)(struct ebt_entry_match *m);
	int (*parse)(int c, char **argv, int argc,
	        const struct ebt_u_entry *entry, unsigned int *flags,
	        struct ebt_entry_match **match);
	void (*final_check)(const struct ebt_u_entry *entry,
	   const struct ebt_entry_match *match,
	   const char *name, unsigned int hookmask, unsigned int time);
	void (*print)(const struct ebt_u_entry *entry,
	   const struct ebt_entry_match *match);
	int (*compare)(const struct ebt_entry_match *m1,
	   const struct ebt_entry_match *m2);
	const struct option *extra_ops;
	// can be used e.g. to check for multiple occurance of the same option
	unsigned int flags;
	unsigned int option_offset;
	struct ebt_entry_match *m;
	// if used == 1 we no longer have to add it to
	// the match chain of the new entry
	unsigned int used;
	struct ebt_u_match *next;
};

struct ebt_u_watcher
{
	char name[EBT_FUNCTION_MAXNAMELEN];
	unsigned int size;
	void (*help)(void);
	void (*init)(struct ebt_entry_watcher *w);
	int (*parse)(int c, char **argv, int argc,
	   const struct ebt_u_entry *entry, unsigned int *flags,
	   struct ebt_entry_watcher **watcher);
	void (*final_check)(const struct ebt_u_entry *entry,
	   const struct ebt_entry_watcher *watch, const char *name,
	   unsigned int hookmask, unsigned int time);
	void (*print)(const struct ebt_u_entry *entry,
	   const struct ebt_entry_watcher *watcher);
	int (*compare)(const struct ebt_entry_watcher *w1,
	   const struct ebt_entry_watcher *w2);
	const struct option *extra_ops;
	unsigned int flags;
	unsigned int option_offset;
	struct ebt_entry_watcher *w;
	unsigned int used;
	struct ebt_u_watcher *next;
};

struct ebt_u_target
{
	char name[EBT_FUNCTION_MAXNAMELEN];
	unsigned int size;
	void (*help)(void);
	void (*init)(struct ebt_entry_target *t);
	int (*parse)(int c, char **argv, int argc,
	   const struct ebt_u_entry *entry, unsigned int *flags,
	   struct ebt_entry_target **target);
	void (*final_check)(const struct ebt_u_entry *entry,
	   const struct ebt_entry_target *target, const char *name,
	   unsigned int hookmask, unsigned int time);
	void (*print)(const struct ebt_u_entry *entry,
	   const struct ebt_entry_target *target);
	int (*compare)(const struct ebt_entry_target *t1,
	   const struct ebt_entry_target *t2);
	const struct option *extra_ops;
	unsigned int option_offset;
	unsigned int flags;
	struct ebt_entry_target *t;
	unsigned int used;
	struct ebt_u_target *next;
};

void register_table(struct ebt_u_table *);
void register_match(struct ebt_u_match *);
void register_watcher(struct ebt_u_watcher *);
void register_target(struct ebt_u_target *t);
int get_table(struct ebt_u_replace *repl);
struct ebt_u_target *find_target(const char *name);
struct ebt_u_match *find_match(const char *name);
struct ebt_u_watcher *find_watcher(const char *name);
struct ebt_u_table *find_table(char *name);
void deliver_counters(struct ebt_u_replace *repl);
void deliver_table(struct ebt_u_replace *repl);
int name_to_number(char *name, uint16_t *proto);
int number_to_name(unsigned short proto, char *name);
void check_option(unsigned int *flags, unsigned int mask);
int check_inverse(const char option[]);
void __print_bug(char *file, int line, char *format, ...);
#define print_bug(format, args...) \
   __print_bug(__FILE__, __LINE__, format, ##args)
#define print_error(format, args...) {printf(format".\n", ##args); exit(-1);}
#define print_memory() {printf("Ebtables: " __FILE__ " " __FUNCTION__ \
   " %d :Out of memory.\n", __LINE__); exit(-1);}

// used for keeping the rule counters right during rule adds or deletes
#define CNT_NORM 0
#define CNT_DEL 1
#define CNT_ADD 2
#define CNT_END 3
#define CNT_ZERO 4

extern char *standard_targets[NUM_STANDARD_TARGETS];
// Transforms a target string into the right integer,
// returns 0 on success.
#define FILL_TARGET(_str, _pos) ({                        \
	int _i, _ret = 0;                                 \
	for (_i = 0; _i < NUM_STANDARD_TARGETS; _i++)     \
		if (!strcmp(_str, standard_targets[_i])) {\
			_pos = -_i - 1;                   \
			break;                            \
		}                                         \
	if (_i == NUM_STANDARD_TARGETS)                   \
		_ret = 1;                                 \
	_ret;                                             \
})

// Transforms the target value to an index into standard_targets[]
#define TARGET_INDEX(_value) (-_value - 1)
// Returns a target string corresponding to the value
#define TARGET_NAME(_value) (standard_targets[TARGET_INDEX(_value)])
// True if the hook mask denotes that the rule is in a base chain
#define BASE_CHAIN (hookmask & (1 << NF_BR_NUMHOOKS))
// Clear the bit in the hook_mask that tells if the rule is on a base chain
#define CLEAR_BASE_CHAIN_BIT (hookmask &= ~(1 << NF_BR_NUMHOOKS))
#endif /* EBTABLES_U_H */