--- /dev/null
+#ifndef _IPT_POLICY_H
+#define _IPT_POLICY_H
+
+#define IPT_POLICY_MAX_ELEM 4
+
+enum ipt_policy_flags
+{
+ IPT_POLICY_MATCH_IN = 0x1,
+ IPT_POLICY_MATCH_OUT = 0x2,
+ IPT_POLICY_MATCH_NONE = 0x4,
+ IPT_POLICY_MATCH_STRICT = 0x8,
+};
+
+enum ipt_policy_modes
+{
+ IPT_POLICY_MODE_TRANSPORT,
+ IPT_POLICY_MODE_TUNNEL
+};
+
+struct ipt_policy_spec
+{
+ u_int8_t saddr:1,
+ daddr:1,
+ proto:1,
+ mode:1,
+ spi:1,
+ reqid:1;
+};
+
+struct ipt_policy_elem
+{
+ u_int32_t saddr;
+ u_int32_t smask;
+ u_int32_t daddr;
+ u_int32_t 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;
+};
+
+#endif /* _IPT_POLICY_H */
--- /dev/null
+#ifndef _IP6T_POLICY_H
+#define _IP6T_POLICY_H
+
+#define IP6T_POLICY_MAX_ELEM 4
+
+enum ip6t_policy_flags
+{
+ IP6T_POLICY_MATCH_IN = 0x1,
+ IP6T_POLICY_MATCH_OUT = 0x2,
+ IP6T_POLICY_MATCH_NONE = 0x4,
+ IP6T_POLICY_MATCH_STRICT = 0x8,
+};
+
+enum ip6t_policy_modes
+{
+ IP6T_POLICY_MODE_TRANSPORT,
+ IP6T_POLICY_MODE_TUNNEL
+};
+
+struct ip6t_policy_spec
+{
+ u_int8_t saddr:1,
+ daddr:1,
+ proto:1,
+ mode:1,
+ spi:1,
+ reqid:1;
+};
+
+struct ip6t_policy_elem
+{
+ struct in6_addr saddr;
+ struct in6_addr smask;
+ struct in6_addr daddr;
+ struct in6_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;
+};
+
+#endif /* _IP6T_POLICY_H */
To compile it as a module, choose M here. If unsure, say N.
+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"
obj-$(CONFIG_IP_NF_MATCH_REALM) += ipt_realm.o
obj-$(CONFIG_IP_NF_MATCH_ADDRTYPE) += ipt_addrtype.o
obj-$(CONFIG_IP_NF_MATCH_PHYSDEV) += ipt_physdev.o
+obj-$(CONFIG_IP_NF_MATCH_POLICY) += ipt_policy.o
obj-$(CONFIG_IP_NF_MATCH_COMMENT) += ipt_comment.o
obj-$(CONFIG_IP_NF_MATCH_STRING) += ipt_string.o
--- /dev/null
+/* 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(x,y) (!e->match.x || ((e->x == (y)) ^ e->invert.x))
+
+ return MATCH(saddr, x->props.saddr.a4 & e->smask) &&
+ MATCH(daddr, x->id.daddr.a4 & e->dmask) &&
+ 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 ? 1 : 0;
+}
+
+static int match(const struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ const void *matchinfo, int offset, 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 struct ipt_ip *ip,
+ void *matchinfo, unsigned int matchsize,
+ unsigned int hook_mask)
+{
+ struct ipt_policy_info *info = matchinfo;
+
+ if (matchsize != IPT_ALIGN(sizeof(*info))) {
+ printk(KERN_ERR "ipt_policy: matchsize %u != %zu\n",
+ matchsize, IPT_ALIGN(sizeof(*info)));
+ return 0;
+ }
+ 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,
+ .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);
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"
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
--- /dev/null
+/* 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 || \
+ ((ip6_masked_addrcmp((z), &e->x, &e->y)) == 0) ^ 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 ? 1 : 0;
+}
+
+static int match(const struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ 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 struct ip6t_ip6 *ip,
+ void *matchinfo, unsigned int matchsize,
+ unsigned int hook_mask)
+{
+ struct ip6t_policy_info *info = matchinfo;
+
+ if (matchsize != IP6T_ALIGN(sizeof(*info))) {
+ printk(KERN_ERR "ip6t_policy: matchsize %u != %zu\n",
+ matchsize, IP6T_ALIGN(sizeof(*info)));
+ return 0;
+ }
+ 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,
+ .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);