remarkable-linux/net/netfilter/xt_comment.c
Harald Welte 2e4e6a17af [NETFILTER] x_tables: Abstraction layer for {ip,ip6,arp}_tables
This monster-patch tries to do the best job for unifying the data
structures and backend interfaces for the three evil clones ip_tables,
ip6_tables and arp_tables.  In an ideal world we would never have
allowed this kind of copy+paste programming... but well, our world
isn't (yet?) ideal.

o introduce a new x_tables module
o {ip,arp,ip6}_tables depend on this x_tables module
o registration functions for tables, matches and targets are only
  wrappers around x_tables provided functions
o all matches/targets that are used from ip_tables and ip6_tables
  are now implemented as xt_FOOBAR.c files and provide module aliases
  to ipt_FOOBAR and ip6t_FOOBAR
o header files for xt_matches are in include/linux/netfilter/,
  include/linux/netfilter_{ipv4,ipv6} contains compatibility wrappers
  around the xt_FOOBAR.h headers

Based on this patchset we're going to further unify the code,
gradually getting rid of all the layer 3 specific assumptions.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-12 14:06:43 -08:00

81 lines
1.6 KiB
C

/*
* Implements a dummy match to allow attaching comments to rules
*
* 2003-05-13 Brad Fisher (brad@info-link.net)
*/
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_comment.h>
MODULE_AUTHOR("Brad Fisher <brad@info-link.net>");
MODULE_DESCRIPTION("iptables comment match module");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_comment");
MODULE_ALIAS("ip6t_comment");
static int
match(const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const void *matchinfo,
int offset,
unsigned int protooff,
int *hotdrop)
{
/* We always match */
return 1;
}
static int
checkentry(const char *tablename,
const void *ip,
void *matchinfo,
unsigned int matchsize,
unsigned int hook_mask)
{
/* Check the size */
if (matchsize != XT_ALIGN(sizeof(struct xt_comment_info)))
return 0;
return 1;
}
static struct xt_match comment_match = {
.name = "comment",
.match = match,
.checkentry = checkentry,
.me = THIS_MODULE
};
static struct xt_match comment6_match = {
.name = "comment",
.match = match,
.checkentry = checkentry,
.me = THIS_MODULE
};
static int __init init(void)
{
int ret;
ret = xt_register_match(AF_INET, &comment_match);
if (ret)
return ret;
ret = xt_register_match(AF_INET6, &comment6_match);
if (ret)
xt_unregister_match(AF_INET, &comment_match);
return ret;
}
static void __exit fini(void)
{
xt_unregister_match(AF_INET, &comment_match);
xt_unregister_match(AF_INET6, &comment6_match);
}
module_init(init);
module_exit(fini);