[IPSEC] xfrm: Abstract out encapsulation modes

This patch adds the structure xfrm_mode.  It is meant to represent
the operations carried out by transport/tunnel modes.

By doing this we allow additional encapsulation modes to be added
without clogging up the xfrm_input/xfrm_output paths.

Candidate modes include 4-to-6 tunnel mode, 6-to-4 tunnel mode, and
BEET modes.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index ee62c239a7e3..17b29ec3c417 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -77,6 +77,8 @@ static void xfrm_state_gc_destroy(struct xfrm_state *x)
         kfree(x->ealg);
         kfree(x->calg);
         kfree(x->encap);
+        if (x->mode)
+                xfrm_put_mode(x->mode);
         if (x->type) {
                 x->type->destructor(x);
                 xfrm_put_type(x->type);
@@ -1193,6 +1195,10 @@ int xfrm_init_state(struct xfrm_state *x)
         if (err)
                 goto error;
 
+        x->mode = xfrm_get_mode(x->props.mode, family);
+        if (x->mode == NULL)
+                goto error;
+
         x->km.state = XFRM_STATE_VALID;
 
 error: