/*
* x_tables core - Backend for {ip,ip6,arp}_tables
*
* Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
*
* Based on existing ip_tables code which is
* Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
* Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/kernel.h>
#include <linux/socket.h>
#include <linux/net.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/mutex.h>
#include <linux/mm.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_arp.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_DESCRIPTION("[ip,ip6,arp]_tables backend module");
#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
struct xt_af {
struct mutex mutex;
struct list_head match;
struct list_head target;
struct list_head tables;
struct mutex compat_mutex;
};
static struct xt_af *xt;
#ifdef DEBUG_IP_FIREWALL_USER
#define duprintf(format, args...) printk(format , ## args)
#else
#define duprintf(format, args...)
#endif
enum {
TABLE,
TARGET,
MATCH,
};
static const char *xt_prefix[NPROTO] = {
[AF_INET] = "ip",
[AF_INET6] = "ip6",
[NF_ARP] = "arp",
};
/* Registration hooks for targets. */
int
xt_register_target(struct xt_target *target)
{
int ret, af = target->family;
ret = mutex_lock_interruptible(&xt[af].mutex);
if (ret != 0)
return ret;
list_add(&target->list, &xt[af].target);
mutex_unlock(&xt[af].mutex);
return ret;
}
EXPORT_SYMBOL(xt_register_target);
void
xt_unregister_target(struct xt_target *target)
{
int af = target->family;
mutex_lock(&xt[af].mutex);
list_del(&target->list);
mutex_unlock(&xt[af].mutex);
}
EXPORT_SYMBOL(xt_unregister_target);
int
xt_register_targets(struct xt_target *target, unsigned int n)
{
unsigned int i;
int err = 0;
for (i = 0; i < n; i++) {
err = xt_register_target(&target[i]);
if (err)
goto err;
}
return err;
err:
if (i > 0)
xt_unregister_targets(target, i);
return err;
}
EXPORT_SYMBOL(xt_register_targets);
void
xt_unregister_targets(struct xt_target *target, unsigned int n)
{
unsigned int i;
for (i = 0; i < n; i++)
xt_unregister_target(&target[i]);
}
EXPORT_SYMBOL(xt_unregister_targets);
int
xt_register_match(struct xt_match *match)
{
int ret, af = match->family;
ret = mutex_lock_interruptible(&xt[af].mutex);
if (ret != 0)
return ret;
list_add(&match->list, &xt[af].match);
mutex_unlock(&xt[af].mutex);
return ret;
}
EXPORT_SYMBOL(xt_register_match);
void
xt_unregister_match(struct xt_match *match)
{
int af = match->family;
mutex_lock(&xt[af].mutex);
list_del(&match->list);
mutex_unlock(&xt[af].mutex);
}
EXPORT_SYMBOL(xt_unregister_match);
int
xt_register_matches(struct xt_match *match, unsigned int n)
{
unsigned int i;
int err = 0;
for (i = 0; i < n; i++) {
err = xt_register_match(&match[i]);
if (err)
goto err;
}
return err;
err:
if (i > 0)
xt_unregister_matches(match, i);
return err;
}
EXPORT_SYMBOL(xt_register_matches);
void
xt_unregister_matches(struct xt_match *match, unsigned int n)
{
unsigned int i;
for (i = 0; i < n; i++)
xt_unregister_match(&match[i]);
}
EXPORT_SYMBOL(xt_unregister_matches);
/*
* These are weird, but module loading must not be done with mutex
* held (since they will register), and we have to have a single
* function to use try_then_request_module().
*/
/* Find match, grabs ref. Returns ERR_PTR() on error. */
struct xt_match *xt_find_match(int af, const char *name, u8 revision)
{
struct xt_match *m;
int err = 0;
if (mutex_lock_interruptible(&xt[af].mutex) != 0)
return ERR_PTR(-EINTR);
list_for_each_entry(m, &xt[af].match, list) {
if (strcmp(m->name, name) == 0) {
if (m->revision == revision) {
if (try_module_get(m->me)) {
mutex_unlock(&xt[af].mutex);
return m;
}
} else
err