[NETFILTER]: x_tables: replace IPv4 dscp match by address family independent version

This replaces IPv4 dscp match by address family independent version.
This also
	- utilizes dsfield.h to get the DS field in IPv4/IPv6 header, and
	- checks for the DSCP value from user space.
	- fixes Kconfig help text.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Yasuyuki Kozakai 2006-08-22 00:29:37 -07:00 committed by David S. Miller
parent 131852176c
commit 9ba1627617
8 changed files with 154 additions and 74 deletions

View file

@ -0,0 +1,23 @@
/* x_tables module for matching the IPv4/IPv6 DSCP field
*
* (C) 2002 Harald Welte <laforge@gnumonks.org>
* This software is distributed under GNU GPL v2, 1991
*
* See RFC2474 for a description of the DSCP field within the IP Header.
*
* xt_dscp.h,v 1.3 2002/08/05 19:00:21 laforge Exp
*/
#ifndef _XT_DSCP_H
#define _XT_DSCP_H
#define XT_DSCP_MASK 0xfc /* 11111100 */
#define XT_DSCP_SHIFT 2
#define XT_DSCP_MAX 0x3f /* 00111111 */
/* match info */
struct xt_dscp_info {
u_int8_t dscp;
u_int8_t invert;
};
#endif /* _XT_DSCP_H */

View file

@ -10,14 +10,12 @@
#ifndef _IPT_DSCP_H
#define _IPT_DSCP_H
#define IPT_DSCP_MASK 0xfc /* 11111100 */
#define IPT_DSCP_SHIFT 2
#define IPT_DSCP_MAX 0x3f /* 00111111 */
#include <linux/netfilter/xt_dscp.h>
/* match info */
struct ipt_dscp_info {
u_int8_t dscp;
u_int8_t invert;
};
#define IPT_DSCP_MASK XT_DSCP_MASK
#define IPT_DSCP_SHIFT XT_DSCP_SHIFT
#define IPT_DSCP_MAX XT_DSCP_MAX
#define ipt_dscp_info xt_dscp_info
#endif /* _IPT_DSCP_H */

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@ -278,17 +278,6 @@ config IP_NF_MATCH_ECN
To compile it as a module, choose M here. If unsure, say N.
config IP_NF_MATCH_DSCP
tristate "DSCP match support"
depends on IP_NF_IPTABLES
help
This option adds a `DSCP' match, which allows you to match against
the IPv4 header DSCP field (DSCP codepoint).
The DSCP codepoint can have any value between 0x0 and 0x4f.
To compile it as a module, choose M here. If unsure, say N.
config IP_NF_MATCH_AH
tristate "AH match support"
depends on IP_NF_IPTABLES

View file

@ -59,7 +59,6 @@ obj-$(CONFIG_IP_NF_MATCH_OWNER) += ipt_owner.o
obj-$(CONFIG_IP_NF_MATCH_TOS) += ipt_tos.o
obj-$(CONFIG_IP_NF_MATCH_RECENT) += ipt_recent.o
obj-$(CONFIG_IP_NF_MATCH_ECN) += ipt_ecn.o
obj-$(CONFIG_IP_NF_MATCH_DSCP) += ipt_dscp.o
obj-$(CONFIG_IP_NF_MATCH_AH) += ipt_ah.o
obj-$(CONFIG_IP_NF_MATCH_TTL) += ipt_ttl.o
obj-$(CONFIG_IP_NF_MATCH_ADDRTYPE) += ipt_addrtype.o

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@ -1,54 +0,0 @@
/* IP tables module for matching the value of the IPv4 DSCP field
*
* ipt_dscp.c,v 1.3 2002/08/05 19:00:21 laforge Exp
*
* (C) 2002 by Harald Welte <laforge@netfilter.org>
*
* 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 <linux/netfilter_ipv4/ipt_dscp.h>
#include <linux/netfilter_ipv4/ip_tables.h>
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_DESCRIPTION("iptables DSCP matching module");
MODULE_LICENSE("GPL");
static int match(const struct sk_buff *skb,
const struct net_device *in, const struct net_device *out,
const struct xt_match *match, const void *matchinfo,
int offset, unsigned int protoff, int *hotdrop)
{
const struct ipt_dscp_info *info = matchinfo;
const struct iphdr *iph = skb->nh.iph;
u_int8_t sh_dscp = ((info->dscp << IPT_DSCP_SHIFT) & IPT_DSCP_MASK);
return ((iph->tos&IPT_DSCP_MASK) == sh_dscp) ^ info->invert;
}
static struct ipt_match dscp_match = {
.name = "dscp",
.match = match,
.matchsize = sizeof(struct ipt_dscp_info),
.me = THIS_MODULE,
};
static int __init ipt_dscp_init(void)
{
return ipt_register_match(&dscp_match);
}
static void __exit ipt_dscp_fini(void)
{
ipt_unregister_match(&dscp_match);
}
module_init(ipt_dscp_init);
module_exit(ipt_dscp_fini);

View file

@ -263,6 +263,17 @@ config NETFILTER_XT_MATCH_DCCP
If you want to compile it as a module, say M here and read
<file:Documentation/modules.txt>. If unsure, say `N'.
config NETFILTER_XT_MATCH_DSCP
tristate '"DSCP" match support'
depends on NETFILTER_XTABLES
help
This option adds a `DSCP' match, which allows you to match against
the IPv4/IPv6 header DSCP field (differentiated services codepoint).
The DSCP field can have any value between 0x0 and 0x3f inclusive.
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_MATCH_ESP
tristate '"ESP" match support'
depends on NETFILTER_XTABLES

View file

@ -37,6 +37,7 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_CONNBYTES) += xt_connbytes.o
obj-$(CONFIG_NETFILTER_XT_MATCH_CONNMARK) += xt_connmark.o
obj-$(CONFIG_NETFILTER_XT_MATCH_CONNTRACK) += xt_conntrack.o
obj-$(CONFIG_NETFILTER_XT_MATCH_DCCP) += xt_dccp.o
obj-$(CONFIG_NETFILTER_XT_MATCH_DSCP) += xt_dscp.o
obj-$(CONFIG_NETFILTER_XT_MATCH_ESP) += xt_esp.o
obj-$(CONFIG_NETFILTER_XT_MATCH_HELPER) += xt_helper.o
obj-$(CONFIG_NETFILTER_XT_MATCH_LENGTH) += xt_length.o

113
net/netfilter/xt_dscp.c Normal file
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@ -0,0 +1,113 @@
/* IP tables module for matching the value of the IPv4/IPv6 DSCP field
*
* xt_dscp.c,v 1.3 2002/08/05 19:00:21 laforge Exp
*
* (C) 2002 by Harald Welte <laforge@netfilter.org>
*
* 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 <linux/ip.h>
#include <linux/ipv6.h>
#include <net/dsfield.h>
#include <linux/netfilter/xt_dscp.h>
#include <linux/netfilter/x_tables.h>
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_DESCRIPTION("x_tables DSCP matching module");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_dscp");
MODULE_ALIAS("ip6t_dscp");
static int match(const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct xt_match *match,
const void *matchinfo,
int offset,
unsigned int protoff,
int *hotdrop)
{
const struct xt_dscp_info *info = matchinfo;
u_int8_t dscp = ipv4_get_dsfield(skb->nh.iph) >> XT_DSCP_SHIFT;
return (dscp == info->dscp) ^ !!info->invert;
}
static int match6(const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct xt_match *match,
const void *matchinfo,
int offset,
unsigned int protoff,
int *hotdrop)
{
const struct xt_dscp_info *info = matchinfo;
u_int8_t dscp = ipv6_get_dsfield(skb->nh.ipv6h) >> XT_DSCP_SHIFT;
return (dscp == info->dscp) ^ !!info->invert;
}
static int checkentry(const char *tablename,
const void *info,
const struct xt_match *match,
void *matchinfo,
unsigned int matchsize,
unsigned int hook_mask)
{
const u_int8_t dscp = ((struct xt_dscp_info *)matchinfo)->dscp;
if (dscp > XT_DSCP_MAX) {
printk(KERN_ERR "xt_dscp: dscp %x out of range\n", dscp);
return 0;
}
return 1;
}
static struct xt_match dscp_match = {
.name = "dscp",
.match = match,
.checkentry = checkentry,
.matchsize = sizeof(struct xt_dscp_info),
.family = AF_INET,
.me = THIS_MODULE,
};
static struct xt_match dscp6_match = {
.name = "dscp",
.match = match6,
.checkentry = checkentry,
.matchsize = sizeof(struct xt_dscp_info),
.family = AF_INET6,
.me = THIS_MODULE,
};
static int __init xt_dscp_match_init(void)
{
int ret;
ret = xt_register_match(&dscp_match);
if (ret)
return ret;
ret = xt_register_match(&dscp6_match);
if (ret)
xt_unregister_match(&dscp_match);
return ret;
}
static void __exit xt_dscp_match_fini(void)
{
xt_unregister_match(&dscp_match);
xt_unregister_match(&dscp6_match);
}
module_init(xt_dscp_match_init);
module_exit(xt_dscp_match_fini);