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[NETFILTER]: x_tables: replace IPv4/IPv6 policy match by address family independant version

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Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2006-03-20 18:03:40 -08:00 committed by David S. Miller
parent f2ffd9eeda
commit c4b8851392
13 changed files with 308 additions and 470 deletions
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4
include/linux/netfilter/x_tables.h
View File

@ -126,6 +126,8 @@ struct xt_match
unsigned int matchsize;
unsigned int hooks;
unsigned short proto;
unsigned short family;
u_int8_t revision;
};
@ -169,6 +171,8 @@ struct xt_target
unsigned int targetsize;
unsigned int hooks;
unsigned short proto;
unsigned short family;
u_int8_t revision;
};

58
include/linux/netfilter/xt_policy.h Normal file
View File

@ -0,0 +1,58 @@
#ifndef _XT_POLICY_H
#define _XT_POLICY_H
#define XT_POLICY_MAX_ELEM 4
enum xt_policy_flags
{
XT_POLICY_MATCH_IN = 0x1,
XT_POLICY_MATCH_OUT = 0x2,
XT_POLICY_MATCH_NONE = 0x4,
XT_POLICY_MATCH_STRICT = 0x8,
};
enum xt_policy_modes
{
XT_POLICY_MODE_TRANSPORT,
XT_POLICY_MODE_TUNNEL
};
struct xt_policy_spec
{
u_int8_t saddr:1,
daddr:1,
proto:1,
mode:1,
spi:1,
reqid:1;
};
union xt_policy_addr
{
struct in_addr a4;
struct in6_addr a6;
};
struct xt_policy_elem
{
union xt_policy_addr saddr;
union xt_policy_addr smask;
union xt_policy_addr daddr;
union xt_policy_addr dmask;
u_int32_t spi;
u_int32_t reqid;
u_int8_t proto;
u_int8_t mode;
struct xt_policy_spec match;
struct xt_policy_spec invert;
};
struct xt_policy_info
{
struct xt_policy_elem pol[XT_POLICY_MAX_ELEM];
u_int16_t flags;
u_int16_t len;
};
#endif /* _XT_POLICY_H */

63
include/linux/netfilter_ipv4/ipt_policy.h
View File

@ -1,58 +1,21 @@
#ifndef _IPT_POLICY_H
#define _IPT_POLICY_H
#define IPT_POLICY_MAX_ELEM 4
#define IPT_POLICY_MAX_ELEM XT_POLICY_MAX_ELEM
enum ipt_policy_flags
{
IPT_POLICY_MATCH_IN = 0x1,
IPT_POLICY_MATCH_OUT = 0x2,
IPT_POLICY_MATCH_NONE = 0x4,
IPT_POLICY_MATCH_STRICT = 0x8,
};
/* ipt_policy_flags */
#define IPT_POLICY_MATCH_IN XT_POLICY_MATCH_IN
#define IPT_POLICY_MATCH_OUT XT_POLICY_MATCH_OUT
#define IPT_POLICY_MATCH_NONE XT_POLICY_MATCH_NONE
#define IPT_POLICY_MATCH_STRICT XT_POLICY_MATCH_STRICT
enum ipt_policy_modes
{
IPT_POLICY_MODE_TRANSPORT,
IPT_POLICY_MODE_TUNNEL
};
/* ipt_policy_modes */
#define IPT_POLICY_MODE_TRANSPORT XT_POLICY_MODE_TRANSPORT
#define IPT_POLICY_MODE_TUNNEL XT_POLICY_MODE_TUNNEL
struct ipt_policy_spec
{
u_int8_t saddr:1,
daddr:1,
proto:1,
mode:1,
spi:1,
reqid:1;
};
union ipt_policy_addr
{
struct in_addr a4;
struct in6_addr a6;
};
struct ipt_policy_elem
{
union ipt_policy_addr saddr;
union ipt_policy_addr smask;
union ipt_policy_addr daddr;
union ipt_policy_addr dmask;
u_int32_t spi;
u_int32_t reqid;
u_int8_t proto;
u_int8_t mode;
struct ipt_policy_spec match;
struct ipt_policy_spec invert;
};
struct ipt_policy_info
{
struct ipt_policy_elem pol[IPT_POLICY_MAX_ELEM];
u_int16_t flags;
u_int16_t len;
};
#define ipt_policy_spec xt_policy_spec
#define ipt_policy_addr xt_policy_addr
#define ipt_policy_elem xt_policy_elem
#define ipt_policy_info xt_policy_info
#endif /* _IPT_POLICY_H */

63
include/linux/netfilter_ipv6/ip6t_policy.h
View File

@ -1,58 +1,21 @@
#ifndef _IP6T_POLICY_H
#define _IP6T_POLICY_H
#define IP6T_POLICY_MAX_ELEM 4
#define IP6T_POLICY_MAX_ELEM XT_POLICY_MAX_ELEM
enum ip6t_policy_flags
{
IP6T_POLICY_MATCH_IN = 0x1,
IP6T_POLICY_MATCH_OUT = 0x2,
IP6T_POLICY_MATCH_NONE = 0x4,
IP6T_POLICY_MATCH_STRICT = 0x8,
};
/* ip6t_policy_flags */
#define IP6T_POLICY_MATCH_IN XT_POLICY_MATCH_IN
#define IP6T_POLICY_MATCH_OUT XT_POLICY_MATCH_OUT
#define IP6T_POLICY_MATCH_NONE XT_POLICY_MATCH_NONE
#define IP6T_POLICY_MATCH_STRICT XT_POLICY_MATCH_STRICT
enum ip6t_policy_modes
{
IP6T_POLICY_MODE_TRANSPORT,
IP6T_POLICY_MODE_TUNNEL
};
/* ip6t_policy_modes */
#define IP6T_POLICY_MODE_TRANSPORT XT_POLICY_MODE_TRANSPORT
#define IP6T_POLICY_MODE_TUNNEL XT_POLICY_MODE_TUNNEL
struct ip6t_policy_spec
{
u_int8_t saddr:1,
daddr:1,
proto:1,
mode:1,
spi:1,
reqid:1;
};
union ip6t_policy_addr
{
struct in_addr a4;
struct in6_addr a6;
};
struct ip6t_policy_elem
{
union ip6t_policy_addr saddr;
union ip6t_policy_addr smask;
union ip6t_policy_addr daddr;
union ip6t_policy_addr dmask;
u_int32_t spi;
u_int32_t reqid;
u_int8_t proto;
u_int8_t mode;
struct ip6t_policy_spec match;
struct ip6t_policy_spec invert;
};
struct ip6t_policy_info
{
struct ip6t_policy_elem pol[IP6T_POLICY_MAX_ELEM];
u_int16_t flags;
u_int16_t len;
};
#define ip6t_policy_spec xt_policy_spec
#define ip6t_policy_addr xt_policy_addr
#define ip6t_policy_elem xt_policy_elem
#define ip6t_policy_info xt_policy_info
#endif /* _IP6T_POLICY_H */

10
net/ipv4/netfilter/Kconfig
View File

@ -303,16 +303,6 @@ config IP_NF_MATCH_HASHLIMIT
destination IP' or `500pps from any given source IP' with a single
IPtables rule.
config IP_NF_MATCH_POLICY
tristate "IPsec policy match support"
depends on IP_NF_IPTABLES && XFRM
help
Policy matching allows you to match packets based on the
IPsec policy that was used during decapsulation/will
be used during encapsulation.
To compile it as a module, choose M here. If unsure, say N.
# `filter', generic and specific targets
config IP_NF_FILTER
tristate "Packet filtering"

1
net/ipv4/netfilter/Makefile
View File

@ -57,7 +57,6 @@ obj-$(CONFIG_IP_NF_MATCH_DSCP) += ipt_dscp.o
obj-$(CONFIG_IP_NF_MATCH_AH_ESP) += ipt_ah.o ipt_esp.o
obj-$(CONFIG_IP_NF_MATCH_TTL) += ipt_ttl.o
obj-$(CONFIG_IP_NF_MATCH_ADDRTYPE) += ipt_addrtype.o
obj-$(CONFIG_IP_NF_MATCH_POLICY) += ipt_policy.o
# targets
obj-$(CONFIG_IP_NF_TARGET_REJECT) += ipt_REJECT.o

174
net/ipv4/netfilter/ipt_policy.c
View File

@ -1,174 +0,0 @@
/* IP tables module for matching IPsec policy
*
* Copyright (c) 2004,2005 Patrick McHardy, <kaber@trash.net>
*
* 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/kernel.h>
#include <linux/config.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <net/xfrm.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv4/ipt_policy.h>
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_DESCRIPTION("IPtables IPsec policy matching module");
MODULE_LICENSE("GPL");
static inline int
match_xfrm_state(struct xfrm_state *x, const struct ipt_policy_elem *e)
{
#define MATCH_ADDR(x,y,z) (!e->match.x || \
((e->x.a4.s_addr == (e->y.a4.s_addr & (z))) \
^ e->invert.x))
#define MATCH(x,y) (!e->match.x || ((e->x == (y)) ^ e->invert.x))
return MATCH_ADDR(saddr, smask, x->props.saddr.a4) &&
MATCH_ADDR(daddr, dmask, x->id.daddr.a4) &&
MATCH(proto, x->id.proto) &&
MATCH(mode, x->props.mode) &&
MATCH(spi, x->id.spi) &&
MATCH(reqid, x->props.reqid);
}
static int
match_policy_in(const struct sk_buff *skb, const struct ipt_policy_info *info)
{
const struct ipt_policy_elem *e;
struct sec_path *sp = skb->sp;
int strict = info->flags & IPT_POLICY_MATCH_STRICT;
int i, pos;
if (sp == NULL)
return -1;
if (strict && info->len != sp->len)
return 0;
for (i = sp->len - 1; i >= 0; i--) {
pos = strict ? i - sp->len + 1 : 0;
if (pos >= info->len)
return 0;
e = &info->pol[pos];
if (match_xfrm_state(sp->x[i].xvec, e)) {
if (!strict)
return 1;
} else if (strict)
return 0;
}
return strict ? 1 : 0;
}
static int
match_policy_out(const struct sk_buff *skb, const struct ipt_policy_info *info)
{
const struct ipt_policy_elem *e;
struct dst_entry *dst = skb->dst;
int strict = info->flags & IPT_POLICY_MATCH_STRICT;
int i, pos;
if (dst->xfrm == NULL)
return -1;
for (i = 0; dst && dst->xfrm; dst = dst->child, i++) {
pos = strict ? i : 0;
if (pos >= info->len)
return 0;
e = &info->pol[pos];
if (match_xfrm_state(dst->xfrm, e)) {
if (!strict)
return 1;
} else if (strict)
return 0;
}
return strict ? i == info->len : 0;
}
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_policy_info *info = matchinfo;
int ret;
if (info->flags & IPT_POLICY_MATCH_IN)
ret = match_policy_in(skb, info);
else
ret = match_policy_out(skb, info);
if (ret < 0)
ret = info->flags & IPT_POLICY_MATCH_NONE ? 1 : 0;
else if (info->flags & IPT_POLICY_MATCH_NONE)
ret = 0;
return ret;
}
static int checkentry(const char *tablename, const void *ip_void,
const struct xt_match *match,
void *matchinfo, unsigned int matchsize,
unsigned int hook_mask)
{
struct ipt_policy_info *info = matchinfo;
if (!(info->flags & (IPT_POLICY_MATCH_IN|IPT_POLICY_MATCH_OUT))) {
printk(KERN_ERR "ipt_policy: neither incoming nor "
"outgoing policy selected\n");
return 0;
}
if (hook_mask & (1 << NF_IP_PRE_ROUTING | 1 << NF_IP_LOCAL_IN)
&& info->flags & IPT_POLICY_MATCH_OUT) {
printk(KERN_ERR "ipt_policy: output policy not valid in "
"PRE_ROUTING and INPUT\n");
return 0;
}
if (hook_mask & (1 << NF_IP_POST_ROUTING | 1 << NF_IP_LOCAL_OUT)
&& info->flags & IPT_POLICY_MATCH_IN) {
printk(KERN_ERR "ipt_policy: input policy not valid in "
"POST_ROUTING and OUTPUT\n");
return 0;
}
if (info->len > IPT_POLICY_MAX_ELEM) {
printk(KERN_ERR "ipt_policy: too many policy elements\n");
return 0;
}
return 1;
}
static struct ipt_match policy_match = {
.name = "policy",
.match = match,
.matchsize = sizeof(struct ipt_policy_info),
.checkentry = checkentry,
.me = THIS_MODULE,
};
static int __init init(void)
{
return ipt_register_match(&policy_match);
}
static void __exit fini(void)
{
ipt_unregister_match(&policy_match);
}
module_init(init);
module_exit(fini);

10
net/ipv6/netfilter/Kconfig
View File

@ -133,16 +133,6 @@ config IP6_NF_MATCH_EUI64
To compile it as a module, choose M here. If unsure, say N.
config IP6_NF_MATCH_POLICY
tristate "IPsec policy match support"
depends on IP6_NF_IPTABLES && XFRM
help
Policy matching allows you to match packets based on the
IPsec policy that was used during decapsulation/will
be used during encapsulation.
To compile it as a module, choose M here. If unsure, say N.
# The targets
config IP6_NF_FILTER
tristate "Packet filtering"

1
net/ipv6/netfilter/Makefile
View File

@ -9,7 +9,6 @@ obj-$(CONFIG_IP6_NF_MATCH_OPTS) += ip6t_hbh.o ip6t_dst.o
obj-$(CONFIG_IP6_NF_MATCH_IPV6HEADER) += ip6t_ipv6header.o
obj-$(CONFIG_IP6_NF_MATCH_FRAG) += ip6t_frag.o
obj-$(CONFIG_IP6_NF_MATCH_AHESP) += ip6t_esp.o ip6t_ah.o
obj-$(CONFIG_IP6_NF_MATCH_POLICY) += ip6t_policy.o
obj-$(CONFIG_IP6_NF_MATCH_EUI64) += ip6t_eui64.o
obj-$(CONFIG_IP6_NF_MATCH_MULTIPORT) += ip6t_multiport.o
obj-$(CONFIG_IP6_NF_MATCH_OWNER) += ip6t_owner.o

174
net/ipv6/netfilter/ip6t_policy.c
View File

@ -1,174 +0,0 @@
/* IP tables module for matching IPsec policy
*
* Copyright (c) 2004,2005 Patrick McHardy, <kaber@trash.net>
*
* 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/kernel.h>
#include <linux/config.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <net/xfrm.h>
#include <linux/netfilter_ipv6.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter_ipv6/ip6t_policy.h>
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_DESCRIPTION("IPtables IPsec policy matching module");
MODULE_LICENSE("GPL");
static inline int
match_xfrm_state(struct xfrm_state *x, const struct ip6t_policy_elem *e)
{
#define MATCH_ADDR(x,y,z) (!e->match.x || \
((!ipv6_masked_addr_cmp(&e->x.a6, &e->y.a6, \
z)) \
^ e->invert.x))
#define MATCH(x,y) (!e->match.x || ((e->x == (y)) ^ e->invert.x))
return MATCH_ADDR(saddr, smask, (struct in6_addr *)&x->props.saddr.a6) &&
MATCH_ADDR(daddr, dmask, (struct in6_addr *)&x->id.daddr.a6) &&
MATCH(proto, x->id.proto) &&
MATCH(mode, x->props.mode) &&
MATCH(spi, x->id.spi) &&
MATCH(reqid, x->props.reqid);
}
static int
match_policy_in(const struct sk_buff *skb, const struct ip6t_policy_info *info)
{
const struct ip6t_policy_elem *e;
struct sec_path *sp = skb->sp;
int strict = info->flags & IP6T_POLICY_MATCH_STRICT;
int i, pos;
if (sp == NULL)
return -1;
if (strict && info->len != sp->len)
return 0;
for (i = sp->len - 1; i >= 0; i--) {
pos = strict ? i - sp->len + 1 : 0;
if (pos >= info->len)
return 0;
e = &info->pol[pos];
if (match_xfrm_state(sp->x[i].xvec, e)) {
if (!strict)
return 1;
} else if (strict)
return 0;
}
return strict ? 1 : 0;
}
static int
match_policy_out(const struct sk_buff *skb, const struct ip6t_policy_info *info)
{
const struct ip6t_policy_elem *e;
struct dst_entry *dst = skb->dst;
int strict = info->flags & IP6T_POLICY_MATCH_STRICT;
int i, pos;
if (dst->xfrm == NULL)
return -1;
for (i = 0; dst && dst->xfrm; dst = dst->child, i++) {
pos = strict ? i : 0;
if (pos >= info->len)
return 0;
e = &info->pol[pos];
if (match_xfrm_state(dst->xfrm, e)) {
if (!strict)
return 1;
} else if (strict)
return 0;
}
return strict ? i == info->len : 0;
}
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 ip6t_policy_info *info = matchinfo;
int ret;
if (info->flags & IP6T_POLICY_MATCH_IN)
ret = match_policy_in(skb, info);
else
ret = match_policy_out(skb, info);
if (ret < 0)
ret = info->flags & IP6T_POLICY_MATCH_NONE ? 1 : 0;
else if (info->flags & IP6T_POLICY_MATCH_NONE)
ret = 0;
return ret;
}
static int checkentry(const char *tablename, const void *ip_void,
const struct xt_match *match, void *matchinfo,
unsigned int matchsize, unsigned int hook_mask)
{
struct ip6t_policy_info *info = matchinfo;
if (!(info->flags & (IP6T_POLICY_MATCH_IN|IP6T_POLICY_MATCH_OUT))) {
printk(KERN_ERR "ip6t_policy: neither incoming nor "
"outgoing policy selected\n");
return 0;
}
if (hook_mask & (1 << NF_IP6_PRE_ROUTING | 1 << NF_IP6_LOCAL_IN)
&& info->flags & IP6T_POLICY_MATCH_OUT) {
printk(KERN_ERR "ip6t_policy: output policy not valid in "
"PRE_ROUTING and INPUT\n");
return 0;
}
if (hook_mask & (1 << NF_IP6_POST_ROUTING | 1 << NF_IP6_LOCAL_OUT)
&& info->flags & IP6T_POLICY_MATCH_IN) {
printk(KERN_ERR "ip6t_policy: input policy not valid in "
"POST_ROUTING and OUTPUT\n");
return 0;
}
if (info->len > IP6T_POLICY_MAX_ELEM) {
printk(KERN_ERR "ip6t_policy: too many policy elements\n");
return 0;
}
return 1;
}
static struct ip6t_match policy_match = {
.name = "policy",
.match = match,
.matchsize = sizeof(struct ip6t_policy_info),
.checkentry = checkentry,
.me = THIS_MODULE,
};
static int __init init(void)
{
return ip6t_register_match(&policy_match);
}
static void __exit fini(void)
{
ip6t_unregister_match(&policy_match);
}
module_init(init);
module_exit(fini);

10
net/netfilter/Kconfig
View File

@ -279,6 +279,16 @@ config NETFILTER_XT_MATCH_MARK
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_MATCH_POLICY
tristate 'IPsec "policy" match support'
depends on NETFILTER_XTABLES && XFRM
help
Policy matching allows you to match packets based on the
IPsec policy that was used during decapsulation/will
be used during encapsulation.
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_MATCH_PHYSDEV
tristate '"physdev" match support'
depends on NETFILTER_XTABLES && BRIDGE_NETFILTER

1
net/netfilter/Makefile
View File

@ -40,6 +40,7 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_LENGTH) += xt_length.o
obj-$(CONFIG_NETFILTER_XT_MATCH_LIMIT) += xt_limit.o
obj-$(CONFIG_NETFILTER_XT_MATCH_MAC) += xt_mac.o
obj-$(CONFIG_NETFILTER_XT_MATCH_MARK) += xt_mark.o
obj-$(CONFIG_NETFILTER_XT_MATCH_POLICY) += xt_policy.o
obj-$(CONFIG_NETFILTER_XT_MATCH_PKTTYPE) += xt_pkttype.o
obj-$(CONFIG_NETFILTER_XT_MATCH_REALM) += xt_realm.o
obj-$(CONFIG_NETFILTER_XT_MATCH_SCTP) += xt_sctp.o

209
net/netfilter/xt_policy.c Normal file
View File

@ -0,0 +1,209 @@
/* IP tables module for matching IPsec policy
*
* Copyright (c) 2004,2005 Patrick McHardy, <kaber@trash.net>
*
* 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/kernel.h>
#include <linux/config.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <net/xfrm.h>
#include <linux/netfilter/xt_policy.h>
#include <linux/netfilter/x_tables.h>
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_DESCRIPTION("Xtables IPsec policy matching module");
MODULE_LICENSE("GPL");
static inline int
xt_addr_cmp(const union xt_policy_addr *a1, const union xt_policy_addr *m,
const union xt_policy_addr *a2, unsigned short family)
{
switch (family) {
case AF_INET:
return (a1->a4.s_addr ^ a2->a4.s_addr) & m->a4.s_addr;
case AF_INET6:
return ipv6_masked_addr_cmp(&a1->a6, &m->a6, &a2->a6);
}
return 0;
}
static inline int
match_xfrm_state(struct xfrm_state *x, const struct xt_policy_elem *e,
unsigned short family)
{
#define MATCH_ADDR(x,y,z) (!e->match.x || \
(xt_addr_cmp(&e->x, &e->y, z, family) \
^ e->invert.x))
#define MATCH(x,y) (!e->match.x || ((e->x == (y)) ^ e->invert.x))
return MATCH_ADDR(saddr, smask, (union xt_policy_addr *)&x->props.saddr) &&
MATCH_ADDR(daddr, dmask, (union xt_policy_addr *)&x->id.daddr.a4) &&
MATCH(proto, x->id.proto) &&
MATCH(mode, x->props.mode) &&
MATCH(spi, x->id.spi) &&
MATCH(reqid, x->props.reqid);
}
static int
match_policy_in(const struct sk_buff *skb, const struct xt_policy_info *info,
unsigned short family)
{
const struct xt_policy_elem *e;
struct sec_path *sp = skb->sp;
int strict = info->flags & XT_POLICY_MATCH_STRICT;
int i, pos;
if (sp == NULL)
return -1;
if (strict && info->len != sp->len)
return 0;
for (i = sp->len - 1; i >= 0; i--) {
pos = strict ? i - sp->len + 1 : 0;
if (pos >= info->len)
return 0;
e = &info->pol[pos];
if (match_xfrm_state(sp->x[i].xvec, e, family)) {
if (!strict)
return 1;
} else if (strict)
return 0;
}
return strict ? 1 : 0;
}
static int
match_policy_out(const struct sk_buff *skb, const struct xt_policy_info *info,
unsigned short family)
{
const struct xt_policy_elem *e;
struct dst_entry *dst = skb->dst;
int strict = info->flags & XT_POLICY_MATCH_STRICT;
int i, pos;
if (dst->xfrm == NULL)
return -1;
for (i = 0; dst && dst->xfrm; dst = dst->child, i++) {
pos = strict ? i : 0;
if (pos >= info->len)
return 0;
e = &info->pol[pos];
if (match_xfrm_state(dst->xfrm, e, family)) {
if (!strict)
return 1;
} else if (strict)
return 0;
}
return strict ? i == info->len : 0;
}
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_policy_info *info = matchinfo;
int ret;
if (info->flags & XT_POLICY_MATCH_IN)
ret = match_policy_in(skb, info, match->family);
else
ret = match_policy_out(skb, info, match->family);
if (ret < 0)
ret = info->flags & XT_POLICY_MATCH_NONE ? 1 : 0;
else if (info->flags & XT_POLICY_MATCH_NONE)
ret = 0;
return ret;
}
static int checkentry(const char *tablename, const void *ip_void,
const struct xt_match *match,
void *matchinfo, unsigned int matchsize,
unsigned int hook_mask)
{
struct xt_policy_info *info = matchinfo;
if (!(info->flags & (XT_POLICY_MATCH_IN|XT_POLICY_MATCH_OUT))) {
printk(KERN_ERR "xt_policy: neither incoming nor "
"outgoing policy selected\n");
return 0;
}
/* hook values are equal for IPv4 and IPv6 */
if (hook_mask & (1 << NF_IP_PRE_ROUTING | 1 << NF_IP_LOCAL_IN)
&& info->flags & XT_POLICY_MATCH_OUT) {
printk(KERN_ERR "xt_policy: output policy not valid in "
"PRE_ROUTING and INPUT\n");
return 0;
}
if (hook_mask & (1 << NF_IP_POST_ROUTING | 1 << NF_IP_LOCAL_OUT)
&& info->flags & XT_POLICY_MATCH_IN) {
printk(KERN_ERR "xt_policy: input policy not valid in "
"POST_ROUTING and OUTPUT\n");
return 0;
}
if (info->len > XT_POLICY_MAX_ELEM) {
printk(KERN_ERR "xt_policy: too many policy elements\n");
return 0;
}
return 1;
}
static struct xt_match policy_match = {
.name = "policy",
.family = AF_INET,
.match = match,
.matchsize = sizeof(struct xt_policy_info),
.checkentry = checkentry,
.me = THIS_MODULE,
};
static struct xt_match policy6_match = {
.name = "policy",
.family = AF_INET6,
.match = match,
.matchsize = sizeof(struct xt_policy_info),
.checkentry = checkentry,
.me = THIS_MODULE,
};
static int __init init(void)
{
int ret;
ret = xt_register_match(AF_INET, &policy_match);
if (ret)
return ret;
ret = xt_register_match(AF_INET6, &policy6_match);
if (ret)
xt_unregister_match(AF_INET, &policy_match);
return ret;
}
static void __exit fini(void)
{
xt_unregister_match(AF_INET6, &policy6_match);
xt_unregister_match(AF_INET, &policy_match);
}
module_init(init);
module_exit(fini);
MODULE_ALIAS("ipt_policy");
MODULE_ALIAS("ip6t_policy");