2 * xt_CONNMARK - Netfilter module to modify the connection mark values
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@computergmbh.de>
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.
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.
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
23 #include <linux/module.h>
24 #include <linux/skbuff.h>
26 #include <net/checksum.h>
28 MODULE_AUTHOR("Henrik Nordstrom <hno@marasystems.com>");
29 MODULE_DESCRIPTION("Xtables: connection mark modification");
30 MODULE_LICENSE("GPL");
31 MODULE_ALIAS("ipt_CONNMARK");
32 MODULE_ALIAS("ip6t_CONNMARK");
34 #include <linux/netfilter/x_tables.h>
35 #include <linux/netfilter/xt_CONNMARK.h>
36 #include <net/netfilter/nf_conntrack_ecache.h>
39 connmark_tg_v0(struct sk_buff *skb, const struct xt_target_param *par)
41 const struct xt_connmark_target_info *markinfo = par->targinfo;
43 enum ip_conntrack_info ctinfo;
48 ct = nf_ct_get(skb, &ctinfo);
50 switch(markinfo->mode) {
52 newmark = (ct->mark & ~markinfo->mask) | markinfo->mark;
53 if (newmark != ct->mark) {
55 nf_conntrack_event_cache(IPCT_MARK, ct);
58 case XT_CONNMARK_SAVE:
59 newmark = (ct->mark & ~markinfo->mask) |
60 (skb->mark & markinfo->mask);
61 if (ct->mark != newmark) {
63 nf_conntrack_event_cache(IPCT_MARK, ct);
66 case XT_CONNMARK_RESTORE:
68 diff = (ct->mark ^ mark) & markinfo->mask;
69 skb->mark = mark ^ diff;
78 connmark_tg(struct sk_buff *skb, const struct xt_target_param *par)
80 const struct xt_connmark_tginfo1 *info = par->targinfo;
81 enum ip_conntrack_info ctinfo;
85 ct = nf_ct_get(skb, &ctinfo);
91 newmark = (ct->mark & ~info->ctmask) ^ info->ctmark;
92 if (ct->mark != newmark) {
94 nf_conntrack_event_cache(IPCT_MARK, ct);
97 case XT_CONNMARK_SAVE:
98 newmark = (ct->mark & ~info->ctmask) ^
99 (skb->mark & info->nfmask);
100 if (ct->mark != newmark) {
102 nf_conntrack_event_cache(IPCT_MARK, ct);
105 case XT_CONNMARK_RESTORE:
106 newmark = (skb->mark & ~info->nfmask) ^
107 (ct->mark & info->ctmask);
116 connmark_tg_check_v0(const char *tablename, const void *entry,
117 const struct xt_target *target, void *targinfo,
118 unsigned int hook_mask)
120 const struct xt_connmark_target_info *matchinfo = targinfo;
122 if (matchinfo->mode == XT_CONNMARK_RESTORE) {
123 if (strcmp(tablename, "mangle") != 0) {
124 printk(KERN_WARNING "CONNMARK: restore can only be "
125 "called from \"mangle\" table, not \"%s\"\n",
130 if (matchinfo->mark > 0xffffffff || matchinfo->mask > 0xffffffff) {
131 printk(KERN_WARNING "CONNMARK: Only supports 32bit mark\n");
134 if (nf_ct_l3proto_try_module_get(target->family) < 0) {
135 printk(KERN_WARNING "can't load conntrack support for "
136 "proto=%u\n", target->family);
143 connmark_tg_check(const char *tablename, const void *entry,
144 const struct xt_target *target, void *targinfo,
145 unsigned int hook_mask)
147 if (nf_ct_l3proto_try_module_get(target->family) < 0) {
148 printk(KERN_WARNING "cannot load conntrack support for "
149 "proto=%u\n", target->family);
156 connmark_tg_destroy(const struct xt_target *target, void *targinfo)
158 nf_ct_l3proto_module_put(target->family);
162 struct compat_xt_connmark_target_info {
163 compat_ulong_t mark, mask;
169 static void connmark_tg_compat_from_user_v0(void *dst, void *src)
171 const struct compat_xt_connmark_target_info *cm = src;
172 struct xt_connmark_target_info m = {
177 memcpy(dst, &m, sizeof(m));
180 static int connmark_tg_compat_to_user_v0(void __user *dst, void *src)
182 const struct xt_connmark_target_info *m = src;
183 struct compat_xt_connmark_target_info cm = {
188 return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
190 #endif /* CONFIG_COMPAT */
192 static struct xt_target connmark_tg_reg[] __read_mostly = {
196 .family = NFPROTO_IPV4,
197 .checkentry = connmark_tg_check_v0,
198 .destroy = connmark_tg_destroy,
199 .target = connmark_tg_v0,
200 .targetsize = sizeof(struct xt_connmark_target_info),
202 .compatsize = sizeof(struct compat_xt_connmark_target_info),
203 .compat_from_user = connmark_tg_compat_from_user_v0,
204 .compat_to_user = connmark_tg_compat_to_user_v0,
211 .family = NFPROTO_IPV6,
212 .checkentry = connmark_tg_check_v0,
213 .destroy = connmark_tg_destroy,
214 .target = connmark_tg_v0,
215 .targetsize = sizeof(struct xt_connmark_target_info),
217 .compatsize = sizeof(struct compat_xt_connmark_target_info),
218 .compat_from_user = connmark_tg_compat_from_user_v0,
219 .compat_to_user = connmark_tg_compat_to_user_v0,
226 .family = NFPROTO_IPV4,
227 .checkentry = connmark_tg_check,
228 .target = connmark_tg,
229 .targetsize = sizeof(struct xt_connmark_tginfo1),
230 .destroy = connmark_tg_destroy,
236 .family = NFPROTO_IPV6,
237 .checkentry = connmark_tg_check,
238 .target = connmark_tg,
239 .targetsize = sizeof(struct xt_connmark_tginfo1),
240 .destroy = connmark_tg_destroy,
245 static int __init connmark_tg_init(void)
247 return xt_register_targets(connmark_tg_reg,
248 ARRAY_SIZE(connmark_tg_reg));
251 static void __exit connmark_tg_exit(void)
253 xt_unregister_targets(connmark_tg_reg, ARRAY_SIZE(connmark_tg_reg));
256 module_init(connmark_tg_init);
257 module_exit(connmark_tg_exit);