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v4.10.11
  1/*
  2 *	xt_connmark - Netfilter module to operate on connection marks
  3 *
  4 *	Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com>
  5 *	by Henrik Nordstrom <hno@marasystems.com>
  6 *	Copyright © CC Computer Consultants GmbH, 2007 - 2008
  7 *	Jan Engelhardt <jengelh@medozas.de>
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License as published by
 11 * the Free Software Foundation; either version 2 of the License, or
 12 * (at your option) any later version.
 13 *
 14 * This program is distributed in the hope that it will be useful,
 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 * GNU General Public License for more details.
 18 *
 19 * You should have received a copy of the GNU General Public License
 20 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 
 21 */
 22
 23#include <linux/module.h>
 24#include <linux/skbuff.h>
 25#include <net/netfilter/nf_conntrack.h>
 26#include <net/netfilter/nf_conntrack_ecache.h>
 27#include <linux/netfilter/x_tables.h>
 28#include <linux/netfilter/xt_connmark.h>
 29
 30MODULE_AUTHOR("Henrik Nordstrom <hno@marasystems.com>");
 31MODULE_DESCRIPTION("Xtables: connection mark operations");
 32MODULE_LICENSE("GPL");
 33MODULE_ALIAS("ipt_CONNMARK");
 34MODULE_ALIAS("ip6t_CONNMARK");
 35MODULE_ALIAS("ipt_connmark");
 36MODULE_ALIAS("ip6t_connmark");
 37
 38static unsigned int
 39connmark_tg(struct sk_buff *skb, const struct xt_action_param *par)
 40{
 41	const struct xt_connmark_tginfo1 *info = par->targinfo;
 42	enum ip_conntrack_info ctinfo;
 43	struct nf_conn *ct;
 44	u_int32_t newmark;
 45
 46	ct = nf_ct_get(skb, &ctinfo);
 47	if (ct == NULL || nf_ct_is_untracked(ct))
 48		return XT_CONTINUE;
 49
 50	switch (info->mode) {
 51	case XT_CONNMARK_SET:
 52		newmark = (ct->mark & ~info->ctmask) ^ info->ctmark;
 53		if (ct->mark != newmark) {
 54			ct->mark = newmark;
 55			nf_conntrack_event_cache(IPCT_MARK, ct);
 56		}
 57		break;
 58	case XT_CONNMARK_SAVE:
 59		newmark = (ct->mark & ~info->ctmask) ^
 60		          (skb->mark & info->nfmask);
 61		if (ct->mark != newmark) {
 62			ct->mark = newmark;
 63			nf_conntrack_event_cache(IPCT_MARK, ct);
 64		}
 65		break;
 66	case XT_CONNMARK_RESTORE:
 67		newmark = (skb->mark & ~info->nfmask) ^
 68		          (ct->mark & info->ctmask);
 69		skb->mark = newmark;
 70		break;
 71	}
 72
 73	return XT_CONTINUE;
 74}
 75
 76static int connmark_tg_check(const struct xt_tgchk_param *par)
 77{
 78	int ret;
 79
 80	ret = nf_ct_netns_get(par->net, par->family);
 81	if (ret < 0)
 82		pr_info("cannot load conntrack support for proto=%u\n",
 83			par->family);
 84	return ret;
 85}
 86
 87static void connmark_tg_destroy(const struct xt_tgdtor_param *par)
 88{
 89	nf_ct_netns_put(par->net, par->family);
 90}
 91
 92static bool
 93connmark_mt(const struct sk_buff *skb, struct xt_action_param *par)
 94{
 95	const struct xt_connmark_mtinfo1 *info = par->matchinfo;
 96	enum ip_conntrack_info ctinfo;
 97	const struct nf_conn *ct;
 98
 99	ct = nf_ct_get(skb, &ctinfo);
100	if (ct == NULL || nf_ct_is_untracked(ct))
101		return false;
102
103	return ((ct->mark & info->mask) == info->mark) ^ info->invert;
104}
105
106static int connmark_mt_check(const struct xt_mtchk_param *par)
107{
108	int ret;
109
110	ret = nf_ct_netns_get(par->net, par->family);
111	if (ret < 0)
112		pr_info("cannot load conntrack support for proto=%u\n",
113			par->family);
114	return ret;
115}
116
117static void connmark_mt_destroy(const struct xt_mtdtor_param *par)
118{
119	nf_ct_netns_put(par->net, par->family);
120}
121
122static struct xt_target connmark_tg_reg __read_mostly = {
123	.name           = "CONNMARK",
124	.revision       = 1,
125	.family         = NFPROTO_UNSPEC,
126	.checkentry     = connmark_tg_check,
127	.target         = connmark_tg,
128	.targetsize     = sizeof(struct xt_connmark_tginfo1),
129	.destroy        = connmark_tg_destroy,
130	.me             = THIS_MODULE,
131};
132
133static struct xt_match connmark_mt_reg __read_mostly = {
134	.name           = "connmark",
135	.revision       = 1,
136	.family         = NFPROTO_UNSPEC,
137	.checkentry     = connmark_mt_check,
138	.match          = connmark_mt,
139	.matchsize      = sizeof(struct xt_connmark_mtinfo1),
140	.destroy        = connmark_mt_destroy,
141	.me             = THIS_MODULE,
142};
143
144static int __init connmark_mt_init(void)
145{
146	int ret;
147
148	ret = xt_register_target(&connmark_tg_reg);
149	if (ret < 0)
150		return ret;
151	ret = xt_register_match(&connmark_mt_reg);
152	if (ret < 0) {
153		xt_unregister_target(&connmark_tg_reg);
154		return ret;
155	}
156	return 0;
157}
158
159static void __exit connmark_mt_exit(void)
160{
161	xt_unregister_match(&connmark_mt_reg);
162	xt_unregister_target(&connmark_tg_reg);
163}
164
165module_init(connmark_mt_init);
166module_exit(connmark_mt_exit);
v3.1
  1/*
  2 *	xt_connmark - Netfilter module to operate on connection marks
  3 *
  4 *	Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com>
  5 *	by Henrik Nordstrom <hno@marasystems.com>
  6 *	Copyright © CC Computer Consultants GmbH, 2007 - 2008
  7 *	Jan Engelhardt <jengelh@medozas.de>
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License as published by
 11 * the Free Software Foundation; either version 2 of the License, or
 12 * (at your option) any later version.
 13 *
 14 * This program is distributed in the hope that it will be useful,
 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 * GNU General Public License for more details.
 18 *
 19 * You should have received a copy of the GNU General Public License
 20 * along with this program; if not, write to the Free Software
 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 22 */
 23
 24#include <linux/module.h>
 25#include <linux/skbuff.h>
 26#include <net/netfilter/nf_conntrack.h>
 27#include <net/netfilter/nf_conntrack_ecache.h>
 28#include <linux/netfilter/x_tables.h>
 29#include <linux/netfilter/xt_connmark.h>
 30
 31MODULE_AUTHOR("Henrik Nordstrom <hno@marasystems.com>");
 32MODULE_DESCRIPTION("Xtables: connection mark operations");
 33MODULE_LICENSE("GPL");
 34MODULE_ALIAS("ipt_CONNMARK");
 35MODULE_ALIAS("ip6t_CONNMARK");
 36MODULE_ALIAS("ipt_connmark");
 37MODULE_ALIAS("ip6t_connmark");
 38
 39static unsigned int
 40connmark_tg(struct sk_buff *skb, const struct xt_action_param *par)
 41{
 42	const struct xt_connmark_tginfo1 *info = par->targinfo;
 43	enum ip_conntrack_info ctinfo;
 44	struct nf_conn *ct;
 45	u_int32_t newmark;
 46
 47	ct = nf_ct_get(skb, &ctinfo);
 48	if (ct == NULL)
 49		return XT_CONTINUE;
 50
 51	switch (info->mode) {
 52	case XT_CONNMARK_SET:
 53		newmark = (ct->mark & ~info->ctmask) ^ info->ctmark;
 54		if (ct->mark != newmark) {
 55			ct->mark = newmark;
 56			nf_conntrack_event_cache(IPCT_MARK, ct);
 57		}
 58		break;
 59	case XT_CONNMARK_SAVE:
 60		newmark = (ct->mark & ~info->ctmask) ^
 61		          (skb->mark & info->nfmask);
 62		if (ct->mark != newmark) {
 63			ct->mark = newmark;
 64			nf_conntrack_event_cache(IPCT_MARK, ct);
 65		}
 66		break;
 67	case XT_CONNMARK_RESTORE:
 68		newmark = (skb->mark & ~info->nfmask) ^
 69		          (ct->mark & info->ctmask);
 70		skb->mark = newmark;
 71		break;
 72	}
 73
 74	return XT_CONTINUE;
 75}
 76
 77static int connmark_tg_check(const struct xt_tgchk_param *par)
 78{
 79	int ret;
 80
 81	ret = nf_ct_l3proto_try_module_get(par->family);
 82	if (ret < 0)
 83		pr_info("cannot load conntrack support for proto=%u\n",
 84			par->family);
 85	return ret;
 86}
 87
 88static void connmark_tg_destroy(const struct xt_tgdtor_param *par)
 89{
 90	nf_ct_l3proto_module_put(par->family);
 91}
 92
 93static bool
 94connmark_mt(const struct sk_buff *skb, struct xt_action_param *par)
 95{
 96	const struct xt_connmark_mtinfo1 *info = par->matchinfo;
 97	enum ip_conntrack_info ctinfo;
 98	const struct nf_conn *ct;
 99
100	ct = nf_ct_get(skb, &ctinfo);
101	if (ct == NULL)
102		return false;
103
104	return ((ct->mark & info->mask) == info->mark) ^ info->invert;
105}
106
107static int connmark_mt_check(const struct xt_mtchk_param *par)
108{
109	int ret;
110
111	ret = nf_ct_l3proto_try_module_get(par->family);
112	if (ret < 0)
113		pr_info("cannot load conntrack support for proto=%u\n",
114			par->family);
115	return ret;
116}
117
118static void connmark_mt_destroy(const struct xt_mtdtor_param *par)
119{
120	nf_ct_l3proto_module_put(par->family);
121}
122
123static struct xt_target connmark_tg_reg __read_mostly = {
124	.name           = "CONNMARK",
125	.revision       = 1,
126	.family         = NFPROTO_UNSPEC,
127	.checkentry     = connmark_tg_check,
128	.target         = connmark_tg,
129	.targetsize     = sizeof(struct xt_connmark_tginfo1),
130	.destroy        = connmark_tg_destroy,
131	.me             = THIS_MODULE,
132};
133
134static struct xt_match connmark_mt_reg __read_mostly = {
135	.name           = "connmark",
136	.revision       = 1,
137	.family         = NFPROTO_UNSPEC,
138	.checkentry     = connmark_mt_check,
139	.match          = connmark_mt,
140	.matchsize      = sizeof(struct xt_connmark_mtinfo1),
141	.destroy        = connmark_mt_destroy,
142	.me             = THIS_MODULE,
143};
144
145static int __init connmark_mt_init(void)
146{
147	int ret;
148
149	ret = xt_register_target(&connmark_tg_reg);
150	if (ret < 0)
151		return ret;
152	ret = xt_register_match(&connmark_mt_reg);
153	if (ret < 0) {
154		xt_unregister_target(&connmark_tg_reg);
155		return ret;
156	}
157	return 0;
158}
159
160static void __exit connmark_mt_exit(void)
161{
162	xt_unregister_match(&connmark_mt_reg);
163	xt_unregister_target(&connmark_tg_reg);
164}
165
166module_init(connmark_mt_init);
167module_exit(connmark_mt_exit);