[XFRM] STATE: Add a hook to find offset to be inserted header in outbound.

On current kernel, ip6_find_1stfragopt() is used by IPv6 IPsec to find
offset to be inserted header in outbound for transport mode. (BTW, no
usage may be needed for IPv4 case.)  Mobile IPv6 requires another
logic for routing header and destination options header
respectively. This patch is common platform for the offset and adopts
it to IPsec.

Based on MIPL2 kernel patch.

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 60954fc7eb36..6c0aa51319a5 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -435,7 +435,8 @@ static struct xfrm_type ah6_type =
         .init_state     = ah6_init_state,
         .destructor     = ah6_destroy,
         .input          = ah6_input,
-        .output         = ah6_output
+        .output         = ah6_output,
+        .hdr_offset     = xfrm6_find_1stfragopt,
 };
 
 static struct inet6_protocol ah6_protocol = {