[XFRM] STATE: Add a hook to obtain local/remote outbound address.

Outbound transformation replaces both source and destination address with
state's end-point addresses at the same time when IPsec tunnel mode.
It is also required to change them for Mobile IPv6 route optimization, but we
should care about the following differences:
 - changing result is not end-point but care-of address
 - either source or destination is replaced for each state
This hook is a common platform to change outbound address.
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>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 0d735a5..aa3ac99 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -266,6 +266,8 @@
 	int			(*input)(struct xfrm_state *, struct sk_buff *skb);
 	int			(*output)(struct xfrm_state *, struct sk_buff *pskb);
 	int			(*hdr_offset)(struct xfrm_state *, struct sk_buff *, u8 **);
+	xfrm_address_t		*(*local_addr)(struct xfrm_state *, xfrm_address_t *);
+	xfrm_address_t		*(*remote_addr)(struct xfrm_state *, xfrm_address_t *);
 	/* Estimate maximal size of result of transformation of a dgram */
 	u32			(*get_max_size)(struct xfrm_state *, int size);
 };