The CONFIG_CRYPTO_DEV_QCE_SOFT_THRESHOLD symbol was renamed during
development, but the stringify reference in the parameter description
sneaked by unnoticed.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
QCE hangs when presented with an AES-XTS request whose length is larger
than QCE_SECTOR_SIZE (512-bytes), and is not a multiple of it. Let the
fallback cipher handle them.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Process small blocks using the fallback cipher, as a workaround for an
observed failure (DMA-related, apparently) when computing the GCM ghash
key. This brings a speed gain as well, since it avoids the latency of
using the hardware engine to process small blocks.
Using software for all 16-byte requests would be enough to make GCM
work, but to increase performance, a larger threshold would be better.
Measuring the performance of supported ciphers with openssl speed,
software matches hardware at around 768-1024 bytes.
Considering the 256-bit ciphers, software is 2-3 times faster than qce
at 256-bytes, 30% faster at 512, and about even at 768-bytes. With
128-bit keys, the break-even point would be around 1024-bytes.
This adds the 'aes_sw_max_len' parameter, to set the largest request
length processed by the software fallback. Its default is being set to
512 bytes, a little lower than the break-even point, to balance the cost
in CPU usage.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The qce crypto driver appends an extra entry to the dst sgl, to maintain
private state information.
When the gcm driver sends requests to the ctr skcipher, it passes the
authentication tag after the actual crypto payload, but it must not be
touched.
Commit 1336c2221bee ("crypto: qce - save a sg table slot for result
buf") limited the destination sgl to avoid overwriting the
authentication tag but it assumed the tag would be in a separate sgl
entry.
This is not always the case, so it is better to limit the length of the
destination buffer to req->cryptlen before appending the result buf.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Adjust cra_flags to add CRYPTO_NEED_FALLBACK only for AES ciphers, where
AES-192 is not handled by the qce hardware, and don't allocate & free
the fallback skcipher for other algorithms.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Update the IV after the completion of each cipher operation.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When ctr-aes-qce is used for gcm-mode, an extra sg entry for the
authentication tag is present, causing trouble when the qce driver
prepares the dst-results sg table for dma.
It computes the number of entries needed with sg_nents_for_len, leaving
out the tag entry. Then it creates a sg table with that number plus
one, used to store a result buffer.
When copying the sg table, there's no limit to the number of entries
copied, so the extra slot is filled with the authentication tag sg.
When the driver tries to add the result sg, the list is full, and it
returns EINVAL.
By limiting the number of sg entries copied to the dest table, the slot
for the result buffer is guaranteed to be unused.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
XTS-mode uses two keys, so the keysizes should be doubled in
skcipher_def, and halved when checking if it is AES-128/192/256.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Set blocksize of ctr-aes-qce to 1, so it can operate as a stream cipher,
adding the definition for chucksize instead, where the underlying block
size belongs.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit 7a7ffe65c8 ("crypto: skcipher - Add top-level skcipher interface")
dated 20 august 2015 introduced the new skcipher API which is supposed to
replace both blkcipher and ablkcipher. While all consumers of the API have
been converted long ago, some producers of the ablkcipher remain, forcing
us to keep the ablkcipher support routines alive, along with the matching
code to expose [a]blkciphers via the skcipher API.
So switch this driver to the skcipher API, allowing us to finally drop the
ablkcipher code in the near future.
Reviewed-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Eneas U de Queiroz