The code is simplified by using two __be64 values for the operation
instead of using two arrays of u8. This allows to get rid of the memory
alignment code. In addition, the crypto_xor can be replaced with a
native XOR operation. Finally, the definition of the variables is
re-arranged such that the data structures come before simple variables
to potentially reduce memory space.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We're clearing the wrong memory. The memory corruption is likely
harmless because we weren't going to use that stack memory again but not
zeroing is a potential information leak.
Fixes: e28facde3c ('crypto: keywrap - add key wrapping block chaining mode')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch implements the AES key wrapping as specified in
NIST SP800-38F and RFC3394.
The implementation covers key wrapping without padding.
IV handling: The caller does not provide an IV for encryption,
but must obtain the IV after encryption which would serve as the first
semblock in the ciphertext structure defined by SP800-38F. Conversely,
for decryption, the caller must provide the first semiblock of the data
as the IV and the following blocks as ciphertext.
The key wrapping is an authenticated decryption operation. The caller
will receive EBADMSG during decryption if the authentication failed.
Albeit the standards define the key wrapping for AES only, the template
can be used with any other block cipher that has a block size of 16
bytes. During initialization of the template, that condition is checked.
Any cipher not having a block size of 16 bytes will cause the
initialization to fail.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stephan Mueller