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#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
#include <linux/netfilter_ipv4/ipt_pkttype.h>
#include <linux/netfilter_ipv4/ip_tables.h>
MODULE_LICENSE("GPL");
static int match(const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const void *matchinfo,
int offset,
const void *hdr,
u_int16_t datalen,
int *hotdrop)
{
const struct ipt_pkttype_info *info = matchinfo;
return (skb->pkt_type == info->pkttype) ^ info->invert;
}
static int checkentry(const char *tablename,
const struct ipt_ip *ip,
void *matchinfo,
unsigned int matchsize,
unsigned int hook_mask)
{
/*
if (hook_mask
& ~((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_LOCAL_IN)
| (1 << NF_IP_FORWARD))) {
printk("ipt_pkttype: only valid for PRE_ROUTING, LOCAL_IN or FORWARD.\n");
return 0;
}
*/
if (matchsize != IPT_ALIGN(sizeof(struct ipt_pkttype_info)))
return 0;
return 1;
}
static struct ipt_match pkttype_match
= { { NULL, NULL }, "pkttype", &match, &checkentry, NULL, THIS_MODULE };
static int __init init(void)
{
return ipt_register_match(&pkttype_match);
}
static void __exit fini(void)
{
ipt_unregister_match(&pkttype_match);
}
module_init(init);
module_exit(fini);
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