[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, 6 insertions, 0 deletions

diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index 26f18869f77..b4628fbf8ff 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -17,6 +17,12 @@
 #include <net/ipv6.h>
 #include <net/xfrm.h>
 
+int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
+                          u8 **prevhdr)
+{
+        return ip6_find_1stfragopt(skb, prevhdr);
+}
+
 static int xfrm6_tunnel_check_size(struct sk_buff *skb)
 {
         int mtu, ret = 0;