arm: crypto: reduce priority of bit-sliced AES cipher

[ Not upstream because this is a minimal fix for a bug where arm32
  kernels can use a much slower implementation of AES than is actually
  available, potentially forcing vendors to disable encryption on their
  devices.]

All the aes-bs (bit-sliced) and aes-ce (cryptographic extensions)
algorithms had a priority of 300.  This is undesirable because it means
an aes-bs algorithm may be used when an aes-ce algorithm is available.
The aes-ce algorithms have much better performance (up to 10x faster).

Fix it by decreasing the priority of the aes-bs algorithms to 250.

This was fixed upstream by commit cc477bf64573 ("crypto: arm/aes -
replace bit-sliced OpenSSL NEON code"), but it was just a small part of
a complete rewrite.  This patch just fixes the priority bug for older
kernels.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
This commit is contained in:
Eric Biggers 2017-11-17 11:50:27 -08:00 committed by Greg Kroah-Hartman
parent 49c1e5f032
commit a5bd3edda6

View File

@ -363,7 +363,7 @@ static struct crypto_alg aesbs_algs[] = { {
}, {
.cra_name = "cbc(aes)",
.cra_driver_name = "cbc-aes-neonbs",
.cra_priority = 300,
.cra_priority = 250,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct async_helper_ctx),
@ -383,7 +383,7 @@ static struct crypto_alg aesbs_algs[] = { {
}, {
.cra_name = "ctr(aes)",
.cra_driver_name = "ctr-aes-neonbs",
.cra_priority = 300,
.cra_priority = 250,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct async_helper_ctx),
@ -403,7 +403,7 @@ static struct crypto_alg aesbs_algs[] = { {
}, {
.cra_name = "xts(aes)",
.cra_driver_name = "xts-aes-neonbs",
.cra_priority = 300,
.cra_priority = 250,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct async_helper_ctx),