crypto: keywrap - Remove else after break statement

Remove the else because the if statement has a break statement. Fix the
checkpatch.pl warning.

Signed-off-by: Milan Djurovic <mdjurovic@zohomail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: remove cipher routines from public crypto API

The cipher routines in the crypto API are mostly intended for templates
implementing skcipher modes generically in software, and shouldn't be
used outside of the crypto subsystem. So move the prototypes and all
related definitions to a new header file under include/crypto/internal.
Also, let's use the new module namespace feature to move the symbol
exports into a new namespace CRYPTO_INTERNAL.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: skcipher - Add skcipher_ialg_simple helper

This patch introduces the skcipher_ialg_simple helper which fetches
the crypto_alg structure from a simple skcipher instance's spawn.

This allows us to remove the third argument from the function
skcipher_alloc_instance_simple.

In doing so the reference count to the algorithm is now maintained
by the Crypto API and the caller no longer needs to drop the alg
refcount.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: run initcalls for generic implementations earlier

Use subsys_initcall for registration of all templates and generic
algorithm implementations, rather than module_init. Then change
cryptomgr to use arch_initcall, to place it before the subsys_initcalls.

This is needed so that when both a generic and optimized implementation
of an algorithm are built into the kernel (not loadable modules), the
generic implementation is registered before the optimized one.
Otherwise, the self-tests for the optimized implementation are unable to
allocate the generic implementation for the new comparison fuzz tests.

Note that on arm, a side effect of this change is that self-tests for
generic implementations may run before the unaligned access handler has
been installed. So, unaligned accesses will crash the kernel. This is
arguably a good thing as it makes it easier to detect that type of bug.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: keywrap - convert to skcipher API

Convert the keywrap template from the deprecated "blkcipher" API to the
"skcipher" API, taking advantage of skcipher_alloc_instance_simple() to
simplify it considerably.

Cc: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: keywrap - Add missing ULL suffixes for 64-bit constants

On 32-bit (e.g. with m68k-linux-gnu-gcc-4.1):

crypto/keywrap.c: In function ‘crypto_kw_decrypt’:
crypto/keywrap.c:191: warning: integer constant is too large for ‘long’ type
crypto/keywrap.c: In function ‘crypto_kw_encrypt’:
crypto/keywrap.c:224: warning: integer constant is too large for ‘long’ type

Fixes: 9e49451d7a15365d ("crypto: keywrap - simplify code")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: keywrap - simplify code

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>

crypto: keywrap - memzero the correct memory

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: e28facde3c39 ('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>

crypto: keywrap - add key wrapping block chaining mode

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>