Subversion Repositories or1k

/* This is a module which is used for setting the NFMARK field of an skb. */

#include <linux/module.h>

#include <linux/skbuff.h>

#include <linux/ip.h>

#include <net/checksum.h>

#include <linux/netfilter_ipv4/ip_tables.h>

#include <linux/netfilter_ipv4/ipt_MARK.h>

static unsigned int

target(struct sk_buff **pskb,

       unsigned int hooknum,

       const struct net_device *in,

       const struct net_device *out,

       const void *targinfo,

       void *userinfo)

{

        const struct ipt_mark_target_info *markinfo = targinfo;

        if((*pskb)->nfmark != markinfo->mark) {

                (*pskb)->nfmark = markinfo->mark;

                (*pskb)->nfcache |= NFC_ALTERED;

        }

        return IPT_CONTINUE;

}

static int

checkentry(const char *tablename,

           const struct ipt_entry *e,

           void *targinfo,

           unsigned int targinfosize,

           unsigned int hook_mask)

{

        if (targinfosize != IPT_ALIGN(sizeof(struct ipt_mark_target_info))) {

                printk(KERN_WARNING "MARK: targinfosize %u != %Zu\n",

                       targinfosize,

                       IPT_ALIGN(sizeof(struct ipt_mark_target_info)));

                return 0;

        }

        if (strcmp(tablename, "mangle") != 0) {

                printk(KERN_WARNING "MARK: can only be called from \"mangle\" table, not \"%s\"\n", tablename);

                return 0;

        }

        return 1;

}

static struct ipt_target ipt_mark_reg

= { { NULL, NULL }, "MARK", target, checkentry, NULL, THIS_MODULE };

static int __init init(void)

{

        if (ipt_register_target(&ipt_mark_reg))

                return -EINVAL;

        return 0;

}

static void __exit fini(void)

{

        ipt_unregister_target(&ipt_mark_reg);

}

module_init(init);

module_exit(fini);

MODULE_LICENSE("GPL");