[XFRM] IPV6: Update outbound state timestamp for each sending.

With this patch transformation state is updated last used time
for each sending. Xtime is used for it like other state lifetime
expiration.
Mobile IPv6 enabled nodes will want to know traffic status of each
binding (e.g. judgement to request binding refresh by correspondent node,
or to keep home/care-of nonce alive by mobile node).
The last used timestamp is an important hint about it.
Based on MIPL2 kernel patch.

This patch was also written by: Henrik Petander <petander@tcs.hut.fi>

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>

2 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/xfrm.h b/include/linux/xfrm.h
index b53f799189af..1d8c1f22c12d 100644
--- a/include/linux/xfrm.h
+++ b/include/linux/xfrm.h
@@ -236,6 +236,7 @@ enum xfrm_attr_type_t {
         XFRMA_ETIMER_THRESH,
         XFRMA_SRCADDR,          /* xfrm_address_t */
         XFRMA_COADDR,           /* xfrm_address_t */
+        XFRMA_LASTUSED,
         __XFRMA_MAX
 
 #define XFRMA_MAX (__XFRMA_MAX - 1)
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 872a2a4022b2..248874ecf8df 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -167,6 +167,9 @@ struct xfrm_state
         struct xfrm_lifetime_cur curlft;
         struct timer_list       timer;
 
+        /* Last used time */
+        u64                     lastused;
+
         /* Reference to data common to all the instances of this
          * transformer. */
         struct xfrm_type        *type;