[XFRM]: Add generation count to xfrm_state and xfrm_dst.
Each xfrm_state inserted gets a new generation counter
value. When a bundle is created, the xfrm_dst objects
get the current generation counter of the xfrm_state
they will attach to at dst->xfrm.
xfrm_bundle_ok() will return false if it sees an
xfrm_dst with a generation count different from the
generation count of the xfrm_state that dst points to.
This provides a facility by which to passively and
cheaply invalidate cached IPSEC routes during SA
database changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 445263c..535d43c 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -53,6 +53,7 @@
static unsigned int xfrm_state_hmask __read_mostly;
static unsigned int xfrm_state_hashmax __read_mostly = 1 * 1024 * 1024;
static unsigned int xfrm_state_num;
+static unsigned int xfrm_state_genid;
static inline unsigned int __xfrm4_dst_hash(xfrm_address_t *addr, unsigned int hmask)
{
@@ -745,6 +746,8 @@
{
unsigned int h = xfrm_dst_hash(&x->id.daddr, x->props.family);
+ x->genid = ++xfrm_state_genid;
+
hlist_add_head(&x->bydst, xfrm_state_bydst+h);
xfrm_state_hold(x);
