[XFRM]: Restrict upper layer information by bundle.

On MIPv6 usage, XFRM sub policy is enabled.
When main (IPsec) and sub (MIPv6) policy selectors have the same
address set but different upper layer information (i.e. protocol
number and its ports or type/code), multiple bundle should be created.
However, currently we have issue to use the same bundle created for
the first time with all flows covered by the case.

It is useful for the bundle to have the upper layer information
to be restructured correctly if it does not match with the flow.

1. Bundle was created by two policies
Selector from another policy is added to xfrm_dst.
If the flow does not match the selector, it goes to slow path to
restructure new bundle by single policy.

2. Bundle was created by one policy
Flow cache is added to xfrm_dst as originated one. If the flow does
not match the cache, it goes to slow path to try searching another
policy.

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

1 files changed, 6 insertions, 0 deletions

diff --git a/include/net/flow.h b/include/net/flow.h
index ce4b10d8b412..f3cc1f812619 100644
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -97,4 +97,10 @@ extern void *flow_cache_lookup(struct flowi *key, u16 family, u8 dir,
 extern void flow_cache_flush(void);
 extern atomic_t flow_cache_genid;
 
+static inline int flow_cache_uli_match(struct flowi *fl1, struct flowi *fl2)
+{
+        return (fl1->proto == fl2->proto &&
+                !memcmp(&fl1->uli_u, &fl2->uli_u, sizeof(fl1->uli_u)));
+}
+
 #endif