[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>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/xfrm.h b/include/linux/xfrm.h
index b58adc52448d..c0e41e02234f 100644
--- a/include/linux/xfrm.h
+++ b/include/linux/xfrm.h
@@ -114,6 +114,7 @@ enum
         XFRM_POLICY_IN  = 0,
         XFRM_POLICY_OUT = 1,
         XFRM_POLICY_FWD = 2,
+        XFRM_POLICY_MASK = 3,
         XFRM_POLICY_MAX = 3
 };