This patch replaces the custom xor in CBC with the generic crypto_xor.

It changes the operations for in-place encryption slightly to avoid
calling crypto_xor with tmpbuf since it is not necessarily aligned.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch passes the type/mask along when constructing instances of
templates.  This is in preparation for templates that may support
multiple types of instances depending on what is requested.  For example,
the planned software async crypto driver will use this construct.

For the moment this allows us to check whether the instance constructed
is of the correct type and avoid returning success if the type does not
match.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch allows spawns of specific types (e.g., cipher) to be allocated.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Add PCBC crypto template support as used by RxRPC.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch adds two block cipher algorithms, CBC and ECB.  These
are implemented as templates on top of existing single-block cipher
algorithms.  They invoke the single-block cipher through the new
encrypt_one/decrypt_one interface.

This also optimises the in-place encryption and decryption to remove
the cost of an IV copy each round.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>