1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * "security" table
4 *
5 * This is for use by Mandatory Access Control (MAC) security models,
6 * which need to be able to manage security policy in separate context
7 * to DAC.
8 *
9 * Based on iptable_mangle.c
10 *
11 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
12 * Copyright (C) 2000-2004 Netfilter Core Team <coreteam <at> netfilter.org>
13 * Copyright (C) 2008 Red Hat, Inc., James Morris <jmorris <at> redhat.com>
14 */
15#include <linux/module.h>
16#include <linux/netfilter_ipv4/ip_tables.h>
17#include <linux/slab.h>
18#include <net/ip.h>
19
20MODULE_LICENSE("GPL");
21MODULE_AUTHOR("James Morris <jmorris <at> redhat.com>");
22MODULE_DESCRIPTION("iptables security table, for MAC rules");
23
24#define SECURITY_VALID_HOOKS	(1 << NF_INET_LOCAL_IN) | \
25				(1 << NF_INET_FORWARD) | \
26				(1 << NF_INET_LOCAL_OUT)
27
28static const struct xt_table security_table = {
29	.name		= "security",
30	.valid_hooks	= SECURITY_VALID_HOOKS,
31	.me		= THIS_MODULE,
32	.af		= NFPROTO_IPV4,
33	.priority	= NF_IP_PRI_SECURITY,
34};
35
36static struct nf_hook_ops *sectbl_ops __read_mostly;
37
38static int iptable_security_table_init(struct net *net)
39{
40	struct ipt_replace *repl;
41	int ret;
42
43	repl = ipt_alloc_initial_table(&security_table);
44	if (repl == NULL)
45		return -ENOMEM;
46	ret = ipt_register_table(net, &security_table, repl, sectbl_ops);
47	kfree(repl);
48	return ret;
49}
50
51static void __net_exit iptable_security_net_pre_exit(struct net *net)
52{
53	ipt_unregister_table_pre_exit(net, "security");
54}
55
56static void __net_exit iptable_security_net_exit(struct net *net)
57{
58	ipt_unregister_table_exit(net, "security");
59}
60
61static struct pernet_operations iptable_security_net_ops = {
62	.pre_exit = iptable_security_net_pre_exit,
63	.exit = iptable_security_net_exit,
64};
65
66static int __init iptable_security_init(void)
67{
68	int ret = xt_register_template(&security_table,
69				       iptable_security_table_init);
70
71	if (ret < 0)
72		return ret;
73
74	sectbl_ops = xt_hook_ops_alloc(&security_table, ipt_do_table);
75	if (IS_ERR(sectbl_ops)) {
76		xt_unregister_template(&security_table);
77		return PTR_ERR(sectbl_ops);
78	}
79
80	ret = register_pernet_subsys(&iptable_security_net_ops);
81	if (ret < 0) {
82		xt_unregister_template(&security_table);
83		kfree(sectbl_ops);
84		return ret;
85	}
86
87	return ret;
88}
89
90static void __exit iptable_security_fini(void)
91{
92	unregister_pernet_subsys(&iptable_security_net_ops);
93	kfree(sectbl_ops);
94	xt_unregister_template(&security_table);
95}
96
97module_init(iptable_security_init);
98module_exit(iptable_security_fini);
99