tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* This is a module which is used for setting up fake conntracks
2 * on packets so that they are not seen by the conntrack/NAT code.
3 */
4#include <linux/module.h>
5#include <linux/skbuff.h>
6
7#include <linux/netfilter/x_tables.h>
8#include <net/netfilter/nf_conntrack.h>
9
10MODULE_DESCRIPTION("Xtables: Disabling connection tracking for packets");
11MODULE_LICENSE("GPL");
12MODULE_ALIAS("ipt_NOTRACK");
13MODULE_ALIAS("ip6t_NOTRACK");
14
15static unsigned int
16notrack_tg(struct sk_buff *skb, const struct net_device *in,
17 const struct net_device *out, unsigned int hooknum,
18 const struct xt_target *target, const void *targinfo)
19{
20 /* Previously seen (loopback)? Ignore. */
21 if (skb->nfct != NULL)
22 return XT_CONTINUE;
23
24 /* Attach fake conntrack entry.
25 If there is a real ct entry correspondig to this packet,
26 it'll hang aroun till timing out. We don't deal with it
27 for performance reasons. JK */
28 skb->nfct = &nf_conntrack_untracked.ct_general;
29 skb->nfctinfo = IP_CT_NEW;
30 nf_conntrack_get(skb->nfct);
31
32 return XT_CONTINUE;
33}
34
35static struct xt_target notrack_tg_reg[] __read_mostly = {
36 {
37 .name = "NOTRACK",
38 .family = AF_INET,
39 .target = notrack_tg,
40 .table = "raw",
41 .me = THIS_MODULE,
42 },
43 {
44 .name = "NOTRACK",
45 .family = AF_INET6,
46 .target = notrack_tg,
47 .table = "raw",
48 .me = THIS_MODULE,
49 },
50};
51
52static int __init notrack_tg_init(void)
53{
54 return xt_register_targets(notrack_tg_reg, ARRAY_SIZE(notrack_tg_reg));
55}
56
57static void __exit notrack_tg_exit(void)
58{
59 xt_unregister_targets(notrack_tg_reg, ARRAY_SIZE(notrack_tg_reg));
60}
61
62module_init(notrack_tg_init);
63module_exit(notrack_tg_exit);