1 /* This kernel module is used to modify the connection mark values, or
2 * to optionally restore the skb nfmark from the connection mark
4 * Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com>
5 * by Henrik Nordstrom <hno@marasystems.com>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include <linux/module.h>
22 #include <linux/skbuff.h>
24 #include <net/checksum.h>
26 MODULE_AUTHOR("Henrik Nordstrom <hno@marasytems.com>");
27 MODULE_DESCRIPTION("IP tables CONNMARK matching module");
28 MODULE_LICENSE("GPL");
29 MODULE_ALIAS("ipt_CONNMARK");
31 #include <linux/netfilter/x_tables.h>
32 #include <linux/netfilter/xt_CONNMARK.h>
33 #include <net/netfilter/nf_conntrack_compat.h>
34 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
35 #include <net/netfilter/nf_conntrack_ecache.h>
39 target(struct sk_buff **pskb,
40 const struct net_device *in,
41 const struct net_device *out,
43 const struct xt_target *target,
46 const struct xt_connmark_target_info *markinfo = targinfo;
51 u_int32_t *ctmark = nf_ct_get_mark(*pskb, &ctinfo);
54 switch(markinfo->mode) {
56 newmark = (*ctmark & ~markinfo->mask) | markinfo->mark;
57 if (newmark != *ctmark) {
59 #if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
60 ip_conntrack_event_cache(IPCT_MARK, *pskb);
62 nf_conntrack_event_cache(IPCT_MARK, *pskb);
66 case XT_CONNMARK_SAVE:
67 newmark = (*ctmark & ~markinfo->mask) |
68 ((*pskb)->mark & markinfo->mask);
69 if (*ctmark != newmark) {
71 #if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
72 ip_conntrack_event_cache(IPCT_MARK, *pskb);
74 nf_conntrack_event_cache(IPCT_MARK, *pskb);
78 case XT_CONNMARK_RESTORE:
80 diff = (*ctmark ^ mark) & markinfo->mask;
81 (*pskb)->mark = mark ^ diff;
90 checkentry(const char *tablename,
92 const struct xt_target *target,
94 unsigned int hook_mask)
96 struct xt_connmark_target_info *matchinfo = targinfo;
98 if (nf_ct_l3proto_try_module_get(target->family) < 0) {
99 printk(KERN_WARNING "can't load conntrack support for "
100 "proto=%d\n", target->family);
103 if (matchinfo->mode == XT_CONNMARK_RESTORE) {
104 if (strcmp(tablename, "mangle") != 0) {
105 printk(KERN_WARNING "CONNMARK: restore can only be "
106 "called from \"mangle\" table, not \"%s\"\n",
111 if (matchinfo->mark > 0xffffffff || matchinfo->mask > 0xffffffff) {
112 printk(KERN_WARNING "CONNMARK: Only supports 32bit mark\n");
119 destroy(const struct xt_target *target, void *targinfo)
121 nf_ct_l3proto_module_put(target->family);
125 struct compat_xt_connmark_target_info {
126 compat_ulong_t mark, mask;
132 static void compat_from_user(void *dst, void *src)
134 struct compat_xt_connmark_target_info *cm = src;
135 struct xt_connmark_target_info m = {
140 memcpy(dst, &m, sizeof(m));
143 static int compat_to_user(void __user *dst, void *src)
145 struct xt_connmark_target_info *m = src;
146 struct compat_xt_connmark_target_info cm = {
151 return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
153 #endif /* CONFIG_COMPAT */
155 static struct xt_target xt_connmark_target[] = {
159 .checkentry = checkentry,
162 .targetsize = sizeof(struct xt_connmark_target_info),
164 .compatsize = sizeof(struct compat_xt_connmark_target_info),
165 .compat_from_user = compat_from_user,
166 .compat_to_user = compat_to_user,
173 .checkentry = checkentry,
176 .targetsize = sizeof(struct xt_connmark_target_info),
181 static int __init xt_connmark_init(void)
183 return xt_register_targets(xt_connmark_target,
184 ARRAY_SIZE(xt_connmark_target));
187 static void __exit xt_connmark_fini(void)
189 xt_unregister_targets(xt_connmark_target,
190 ARRAY_SIZE(xt_connmark_target));
193 module_init(xt_connmark_init);
194 module_exit(xt_connmark_fini);