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/* Kernel module to match various things tied to sockets associated with
locally generated outgoing packets. */
/* (C) 2000 Marc Boucher <marc@mbsi.ca>
*
* 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/file.h>
#include <linux/rcupdate.h>
#include <net/sock.h>
#include <linux/netfilter_ipv4/ipt_owner.h>
#include <linux/netfilter/x_tables.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
MODULE_DESCRIPTION("iptables owner match");
static bool
owner_mt(const struct sk_buff *skb, const struct net_device *in,
const struct net_device *out, const struct xt_match *match,
const void *matchinfo, int offset, unsigned int protoff,
bool *hotdrop)
{
const struct ipt_owner_info *info = matchinfo;
if (!skb->sk || !skb->sk->sk_socket || !skb->sk->sk_socket->file)
return false;
if(info->match & IPT_OWNER_UID) {
if ((skb->sk->sk_socket->file->f_uid != info->uid) ^
!!(info->invert & IPT_OWNER_UID))
return false;
}
if(info->match & IPT_OWNER_GID) {
if ((skb->sk->sk_socket->file->f_gid != info->gid) ^
!!(info->invert & IPT_OWNER_GID))
return false;
}
return true;
}
static bool
owner_mt_check(const char *tablename, const void *ip,
const struct xt_match *match, void *matchinfo,
unsigned int hook_mask)
{
const struct ipt_owner_info *info = matchinfo;
if (info->match & (IPT_OWNER_PID|IPT_OWNER_SID|IPT_OWNER_COMM)) {
printk("ipt_owner: pid, sid and command matching "
"not supported anymore\n");
return false;
}
return true;
}
static struct xt_match owner_mt_reg __read_mostly = {
.name = "owner",
.family = AF_INET,
.match = owner_mt,
.matchsize = sizeof(struct ipt_owner_info),
.hooks = (1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_POST_ROUTING),
.checkentry = owner_mt_check,
.me = THIS_MODULE,
};
static int __init owner_mt_init(void)
{
return xt_register_match(&owner_mt_reg);
}
static void __exit owner_mt_exit(void)
{
xt_unregister_match(&owner_mt_reg);
}
module_init(owner_mt_init);
module_exit(owner_mt_exit);
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