remarkable-linux/net/netfilter/xt_pkttype.c
Jan Engelhardt f7108a20de netfilter: xtables: move extension arguments into compound structure (1/6)
The function signatures for Xtables extensions have grown over time.
It involves a lot of typing/replication, and also a bit of stack space
even if they are not used. Realize an NFWS2008 idea and pack them into
structs. The skb remains outside of the struct so gcc can continue to
apply its optimizations.

This patch does this for match extensions' match functions.

A few ambiguities have also been addressed. The "offset" parameter for
example has been renamed to "fragoff" (there are so many different
offsets already) and "protoff" to "thoff" (there is more than just one
protocol here, so clarify).

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:18 +02:00

74 lines
1.8 KiB
C

/* (C) 1999-2001 Michal Ludvig <michal@logix.cz>
*
* 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/module.h>
#include <linux/skbuff.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/netfilter/xt_pkttype.h>
#include <linux/netfilter/x_tables.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michal Ludvig <michal@logix.cz>");
MODULE_DESCRIPTION("Xtables: link layer packet type match");
MODULE_ALIAS("ipt_pkttype");
MODULE_ALIAS("ip6t_pkttype");
static bool
pkttype_mt(const struct sk_buff *skb, const struct xt_match_param *par)
{
const struct xt_pkttype_info *info = par->matchinfo;
u_int8_t type;
if (skb->pkt_type != PACKET_LOOPBACK)
type = skb->pkt_type;
else if (par->match->family == NFPROTO_IPV4 &&
ipv4_is_multicast(ip_hdr(skb)->daddr))
type = PACKET_MULTICAST;
else if (par->match->family == NFPROTO_IPV6 &&
ipv6_hdr(skb)->daddr.s6_addr[0] == 0xFF)
type = PACKET_MULTICAST;
else
type = PACKET_BROADCAST;
return (type == info->pkttype) ^ info->invert;
}
static struct xt_match pkttype_mt_reg[] __read_mostly = {
{
.name = "pkttype",
.family = NFPROTO_IPV4,
.match = pkttype_mt,
.matchsize = sizeof(struct xt_pkttype_info),
.me = THIS_MODULE,
},
{
.name = "pkttype",
.family = NFPROTO_IPV6,
.match = pkttype_mt,
.matchsize = sizeof(struct xt_pkttype_info),
.me = THIS_MODULE,
},
};
static int __init pkttype_mt_init(void)
{
return xt_register_matches(pkttype_mt_reg, ARRAY_SIZE(pkttype_mt_reg));
}
static void __exit pkttype_mt_exit(void)
{
xt_unregister_matches(pkttype_mt_reg, ARRAY_SIZE(pkttype_mt_reg));
}
module_init(pkttype_mt_init);
module_exit(pkttype_mt_exit);