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#include <linux/module.h>
#include <linux/sk_buff.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv4/ipt_workshop.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_DESCRIPTION("OLS2003 workshop iptables module");
static int ws_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_ws_info *info = matchinfo;
const struct iphdr *iph = skb->nh.iph;
if (iph->ttl == info->ttl)
return 1;
return 0;
}
static int ws_checkentry(const char *tablename, const struct ipt_ip *ip,
void *matchinfo, unsigned int matchsize,
unsigned int hook_mask)
{
if (matchsize != IPT_ALIGN(sizeof(struct ipt_ws_info)))
return 0;
return 1;
}
static struct ipt_match ws_match = {
.list = { .prev = NULL, .next = NULL },
.name = "workshop",
.match = &ws_match,
.checkentry = &ws_checkentry,
.destroy = NULL,
.me = THIS_MODULE
};
static int __init init(void)
{
return ipt_register_match(&ws_match);
}
static void __exit fini(void)
{
ipt_unregister_match(&ws_match);
}
module_init(init);
module_exit(fini);
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