[mirror_ubuntu-artful-kernel.git] / net / netfilter / xt_connlabel.c

/*
 * (C) 2013 Astaro GmbH & Co KG
 *
 * 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 <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_ecache.h>
#include <net/netfilter/nf_conntrack_labels.h>
#include <linux/netfilter/x_tables.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
MODULE_DESCRIPTION("Xtables: add/match connection trackling labels");
MODULE_ALIAS("ipt_connlabel");
MODULE_ALIAS("ip6t_connlabel");

static bool
connlabel_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
	const struct xt_connlabel_mtinfo *info = par->matchinfo;
	enum ip_conntrack_info ctinfo;
	struct nf_conn_labels *labels;
	struct nf_conn *ct;
	bool invert = info->options & XT_CONNLABEL_OP_INVERT;

	ct = nf_ct_get(skb, &ctinfo);
	if (ct == NULL)
		return invert;

	labels = nf_ct_labels_find(ct);
	if (!labels)
		return invert;

	if (test_bit(info->bit, labels->bits))
		return !invert;

	if (info->options & XT_CONNLABEL_OP_SET) {
		if (!test_and_set_bit(info->bit, labels->bits))
			nf_conntrack_event_cache(IPCT_LABEL, ct);

		return !invert;
	}

	return invert;
}

static int connlabel_mt_check(const struct xt_mtchk_param *par)
{
	const int options = XT_CONNLABEL_OP_INVERT |
			    XT_CONNLABEL_OP_SET;
	struct xt_connlabel_mtinfo *info = par->matchinfo;
	int ret;

	if (info->options & ~options) {
		pr_err("Unknown options in mask %x\n", info->options);
		return -EINVAL;
	}

	ret = nf_ct_netns_get(par->net, par->family);
	if (ret < 0) {
		pr_info("cannot load conntrack support for proto=%u\n",
							par->family);
		return ret;
	}

	ret = nf_connlabels_get(par->net, info->bit);
	if (ret < 0)
		nf_ct_netns_put(par->net, par->family);
	return ret;
}

static void connlabel_mt_destroy(const struct xt_mtdtor_param *par)
{
	nf_connlabels_put(par->net);
	nf_ct_netns_put(par->net, par->family);
}

static struct xt_match connlabels_mt_reg __read_mostly = {
	.name           = "connlabel",
	.family         = NFPROTO_UNSPEC,
	.checkentry     = connlabel_mt_check,
	.match          = connlabel_mt,
	.matchsize      = sizeof(struct xt_connlabel_mtinfo),
	.destroy        = connlabel_mt_destroy,
	.me             = THIS_MODULE,
};

static int __init connlabel_mt_init(void)
{
	return xt_register_match(&connlabels_mt_reg);
}

static void __exit connlabel_mt_exit(void)
{
	xt_unregister_match(&connlabels_mt_reg);
}

module_init(connlabel_mt_init);
module_exit(connlabel_mt_exit);
Commit	Line	Data
c539f017 FW	1	/*
	2	* (C) 2013 Astaro GmbH & Co KG
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8
	9	#include <linux/module.h>
	10	#include <linux/skbuff.h>
	11	#include <net/netfilter/nf_conntrack.h>
857ed310	12	#include <net/netfilter/nf_conntrack_ecache.h>
c539f017 FW	13	#include <net/netfilter/nf_conntrack_labels.h>
	14	#include <linux/netfilter/x_tables.h>
	15
	16	MODULE_LICENSE("GPL");
	17	MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
	18	MODULE_DESCRIPTION("Xtables: add/match connection trackling labels");
	19	MODULE_ALIAS("ipt_connlabel");
	20	MODULE_ALIAS("ip6t_connlabel");
	21
	22	static bool
	23	connlabel_mt(const struct sk_buff skb, struct xt_action_param par)
	24	{
	25	const struct xt_connlabel_mtinfo *info = par->matchinfo;
	26	enum ip_conntrack_info ctinfo;
857ed310	27	struct nf_conn_labels *labels;
c539f017 FW	28	struct nf_conn *ct;
	29	bool invert = info->options & XT_CONNLABEL_OP_INVERT;
	30
	31	ct = nf_ct_get(skb, &ctinfo);
ab8bc7ed	32	if (ct == NULL)
c539f017 FW	33	return invert;
c539f017 FW	34
857ed310 FW	35	labels = nf_ct_labels_find(ct);
	36	if (!labels)
	37	return invert;
	38
	39	if (test_bit(info->bit, labels->bits))
	40	return !invert;
	41
	42	if (info->options & XT_CONNLABEL_OP_SET) {
	43	if (!test_and_set_bit(info->bit, labels->bits))
	44	nf_conntrack_event_cache(IPCT_LABEL, ct);
	45
	46	return !invert;
	47	}
c539f017	48
857ed310	49	return invert;
c539f017 FW	50	}
	51
	52	static int connlabel_mt_check(const struct xt_mtchk_param *par)
	53	{
	54	const int options = XT_CONNLABEL_OP_INVERT \|
	55	XT_CONNLABEL_OP_SET;
	56	struct xt_connlabel_mtinfo *info = par->matchinfo;
	57	int ret;
c539f017 FW	58
	59	if (info->options & ~options) {
	60	pr_err("Unknown options in mask %x\n", info->options);
	61	return -EINVAL;
	62	}
	63
ecb2421b	64	ret = nf_ct_netns_get(par->net, par->family);
c539f017 FW	65	if (ret < 0) {
	66	pr_info("cannot load conntrack support for proto=%u\n",
	67	par->family);
	68	return ret;
	69	}
	70
adff6c65	71	ret = nf_connlabels_get(par->net, info->bit);
86ca02e7	72	if (ret < 0)
ecb2421b	73	nf_ct_netns_put(par->net, par->family);
c539f017 FW	74	return ret;
	75	}
	76
	77	static void connlabel_mt_destroy(const struct xt_mtdtor_param *par)
	78	{
86ca02e7	79	nf_connlabels_put(par->net);
ecb2421b	80	nf_ct_netns_put(par->net, par->family);
c539f017 FW	81	}
	82
	83	static struct xt_match connlabels_mt_reg __read_mostly = {
	84	.name = "connlabel",
	85	.family = NFPROTO_UNSPEC,
	86	.checkentry = connlabel_mt_check,
	87	.match = connlabel_mt,
	88	.matchsize = sizeof(struct xt_connlabel_mtinfo),
	89	.destroy = connlabel_mt_destroy,
	90	.me = THIS_MODULE,
	91	};
	92
	93	static int __init connlabel_mt_init(void)
	94	{
	95	return xt_register_match(&connlabels_mt_reg);
	96	}
	97
	98	static void __exit connlabel_mt_exit(void)
	99	{
	100	xt_unregister_match(&connlabels_mt_reg);
	101	}
	102
	103	module_init(connlabel_mt_init);
	104	module_exit(connlabel_mt_exit);