alistair23-linux/net/netfilter/xt_CONNMARK.c
Thomas Graf 82e91ffef6 [NET]: Turn nfmark into generic mark
nfmark is being used in various subsystems and has become
the defacto mark field for all kinds of packets. Therefore
it makes sense to rename it to `mark' and remove the
dependency on CONFIG_NETFILTER.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:21:38 -08:00

181 lines
4.8 KiB
C

/* This kernel module is used to modify the connection mark values, or
* to optionally restore the skb nfmark from the connection mark
*
* Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com>
* by Henrik Nordstrom <hno@marasystems.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <net/checksum.h>
MODULE_AUTHOR("Henrik Nordstrom <hno@marasytems.com>");
MODULE_DESCRIPTION("IP tables CONNMARK matching module");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_CONNMARK");
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_CONNMARK.h>
#include <net/netfilter/nf_conntrack_compat.h>
static unsigned int
target(struct sk_buff **pskb,
const struct net_device *in,
const struct net_device *out,
unsigned int hooknum,
const struct xt_target *target,
const void *targinfo)
{
const struct xt_connmark_target_info *markinfo = targinfo;
u_int32_t diff;
u_int32_t mark;
u_int32_t newmark;
u_int32_t ctinfo;
u_int32_t *ctmark = nf_ct_get_mark(*pskb, &ctinfo);
if (ctmark) {
switch(markinfo->mode) {
case XT_CONNMARK_SET:
newmark = (*ctmark & ~markinfo->mask) | markinfo->mark;
if (newmark != *ctmark) {
*ctmark = newmark;
#if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
ip_conntrack_event_cache(IPCT_MARK, *pskb);
#else
nf_conntrack_event_cache(IPCT_MARK, *pskb);
#endif
}
break;
case XT_CONNMARK_SAVE:
newmark = (*ctmark & ~markinfo->mask) |
((*pskb)->mark & markinfo->mask);
if (*ctmark != newmark) {
*ctmark = newmark;
#if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
ip_conntrack_event_cache(IPCT_MARK, *pskb);
#else
nf_conntrack_event_cache(IPCT_MARK, *pskb);
#endif
}
break;
case XT_CONNMARK_RESTORE:
mark = (*pskb)->mark;
diff = (*ctmark ^ mark) & markinfo->mask;
if (diff != 0)
(*pskb)->mark = mark ^ diff;
break;
}
}
return XT_CONTINUE;
}
static int
checkentry(const char *tablename,
const void *entry,
const struct xt_target *target,
void *targinfo,
unsigned int hook_mask)
{
struct xt_connmark_target_info *matchinfo = targinfo;
if (matchinfo->mode == XT_CONNMARK_RESTORE) {
if (strcmp(tablename, "mangle") != 0) {
printk(KERN_WARNING "CONNMARK: restore can only be "
"called from \"mangle\" table, not \"%s\"\n",
tablename);
return 0;
}
}
if (matchinfo->mark > 0xffffffff || matchinfo->mask > 0xffffffff) {
printk(KERN_WARNING "CONNMARK: Only supports 32bit mark\n");
return 0;
}
return 1;
}
#ifdef CONFIG_COMPAT
struct compat_xt_connmark_target_info {
compat_ulong_t mark, mask;
u_int8_t mode;
u_int8_t __pad1;
u_int16_t __pad2;
};
static void compat_from_user(void *dst, void *src)
{
struct compat_xt_connmark_target_info *cm = src;
struct xt_connmark_target_info m = {
.mark = cm->mark,
.mask = cm->mask,
.mode = cm->mode,
};
memcpy(dst, &m, sizeof(m));
}
static int compat_to_user(void __user *dst, void *src)
{
struct xt_connmark_target_info *m = src;
struct compat_xt_connmark_target_info cm = {
.mark = m->mark,
.mask = m->mask,
.mode = m->mode,
};
return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
}
#endif /* CONFIG_COMPAT */
static struct xt_target xt_connmark_target[] = {
{
.name = "CONNMARK",
.family = AF_INET,
.checkentry = checkentry,
.target = target,
.targetsize = sizeof(struct xt_connmark_target_info),
#ifdef CONFIG_COMPAT
.compatsize = sizeof(struct compat_xt_connmark_target_info),
.compat_from_user = compat_from_user,
.compat_to_user = compat_to_user,
#endif
.me = THIS_MODULE
},
{
.name = "CONNMARK",
.family = AF_INET6,
.checkentry = checkentry,
.target = target,
.targetsize = sizeof(struct xt_connmark_target_info),
.me = THIS_MODULE
},
};
static int __init xt_connmark_init(void)
{
need_conntrack();
return xt_register_targets(xt_connmark_target,
ARRAY_SIZE(xt_connmark_target));
}
static void __exit xt_connmark_fini(void)
{
xt_unregister_targets(xt_connmark_target,
ARRAY_SIZE(xt_connmark_target));
}
module_init(xt_connmark_init);
module_exit(xt_connmark_fini);