This reverts commit f1e396c427.
Performance is slightly better with this reverted, especially
for AES-CBC 192.
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
Have clearly separated code to:
* determine whether the assembly-based implementation is available;
* determine whether the intrinsics-based implementation is available;
* select one of the available implementations if any.
Now MBEDTLS_AESNI_HAVE_CODE can be the single interface for aes.c and
aesni.c to determine which AESNI is built.
Change the implementation selection: now, if both implementations are
available, always prefer assembly. Before, the intrinsics were used if
available. This preference is to minimize disruption, and will likely
be revised in a later minor release.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Use a single auxiliary function to determine rk_offset, covering both
setkey_enc and setkey_dec, covering both AESNI and PADLOCK. For AESNI, only
build this when using the intrinsics-based implementation, since the
assembly implementation supports unaligned access.
Simplify "do we need to realign?" to "is the desired offset now equal to
the current offset?".
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The padlock feature is enabled if
```
defined(MBEDTLS_PADLOCK_C) && defined(MBEDTLS_HAVE_X86)
```
with the second macro coming from `padlock.h`. The availability of the
macro `MBEDTLS_PADLOCK_ALIGN16` is coincidentally equivalent to
`MBEDTLS_HAVE_X86` but this is not meaningful.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
As of this commit, to use the intrinsics for MBEDTLS_AESNI_C:
* With MSVC, this should be the default.
* With Clang, build with `clang -maes -mpclmul` or equivalent.
* With GCC, build with `gcc -mpclmul -msse2` or equivalent.
In particular, for now, with a GCC-like compiler, when building specifically
for a target that supports both the AES and GCM instructions, the old
implementation using assembly is selected.
This method for platform selection will likely be improved in the future.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The configuration symbol MBEDTLS_AESNI_C requests AESNI support, but it is
ignored if the platform doesn't have AESNI. This allows keeping
MBEDTLS_AESNI_C enabled (as it is in the default build) when building for
platforms other than x86_64, or when MBEDTLS_HAVE_ASM is disabled.
To facilitate maintenance, always use the symbol MBEDTLS_AESNI_HAVE_CODE to
answer the question "can I call mbedtls_aesni_xxx functions?", rather than
repeating the check `defined(MBEDTLS_AESNI_C) && ...`.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
