[IPSEC]: Added xfrm_decode_session_reverse and xfrmX_policy_check_reverse
RFC 4301 requires us to relookup ICMP traffic that does not match any
policies using the reverse of its payload. This patch adds the functions
xfrm_decode_session_reverse and xfrmX_policy_check_reverse so we can get
the reverse flow to perform such a lookup.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index fe881b6..d6dae5a 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -239,7 +239,8 @@
int (*get_saddr)(xfrm_address_t *saddr, xfrm_address_t *daddr);
struct dst_entry *(*find_bundle)(struct flowi *fl, struct xfrm_policy *policy);
void (*decode_session)(struct sk_buff *skb,
- struct flowi *fl);
+ struct flowi *fl,
+ int reverse);
int (*get_tos)(struct flowi *fl);
int (*fill_dst)(struct xfrm_dst *xdst,
struct net_device *dev);
@@ -844,14 +845,23 @@
#ifdef CONFIG_XFRM
extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
-static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
+static inline int __xfrm_policy_check2(struct sock *sk, int dir,
+ struct sk_buff *skb,
+ unsigned int family, int reverse)
{
+ int ndir = dir | (reverse ? XFRM_POLICY_MASK + 1 : 0);
+
if (sk && sk->sk_policy[XFRM_POLICY_IN])
- return __xfrm_policy_check(sk, dir, skb, family);
+ return __xfrm_policy_check(sk, ndir, skb, family);
return (!xfrm_policy_count[dir] && !skb->sp) ||
(skb->dst->flags & DST_NOPOLICY) ||
- __xfrm_policy_check(sk, dir, skb, family);
+ __xfrm_policy_check(sk, ndir, skb, family);
+}
+
+static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
+{
+ return __xfrm_policy_check2(sk, dir, skb, family, 0);
}
static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
@@ -864,7 +874,34 @@
return xfrm_policy_check(sk, dir, skb, AF_INET6);
}
-extern int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family);
+static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
+ struct sk_buff *skb)
+{
+ return __xfrm_policy_check2(sk, dir, skb, AF_INET, 1);
+}
+
+static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
+ struct sk_buff *skb)
+{
+ return __xfrm_policy_check2(sk, dir, skb, AF_INET6, 1);
+}
+
+extern int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
+ unsigned int family, int reverse);
+
+static inline int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
+ unsigned int family)
+{
+ return __xfrm_decode_session(skb, fl, family, 0);
+}
+
+static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
+ struct flowi *fl,
+ unsigned int family)
+{
+ return __xfrm_decode_session(skb, fl, family, 1);
+}
+
extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
@@ -925,6 +962,22 @@
{
return 1;
}
+static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
+ struct flowi *fl,
+ unsigned int family)
+{
+ return -ENOSYS;
+}
+static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
+ struct sk_buff *skb)
+{
+ return 1;
+}
+static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
+ struct sk_buff *skb)
+{
+ return 1;
+}
#endif
static __inline__