The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.
With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP. These would all need to be fixed if any shash algorithm
actually started sleeping. For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API. However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.
Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk. It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.
Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Some crypto API users allocating a tfm with crypto_alloc_$FOO() are also
specifying the type flags for $FOO, e.g. crypto_alloc_shash() with
CRYPTO_ALG_TYPE_SHASH. But, that's redundant since the crypto API will
override any specified type flag/mask with the correct ones.
So, remove the unneeded flags.
This patch shouldn't change any actual behavior.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The code sample is waiting for an async. crypto op completion.
Adapt sample to use the new generic infrastructure to do the same.
This also fixes a possible data coruption bug created by the
use of wait_for_completion_interruptible() without dealing
correctly with an interrupt aborting the wait prior to the
async op finishing.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
- Fixed bugs in example for shash and rng (added missing "*" and " *").
- Corrected pr_info() in calc_hash().
- Added example usage of calc_hash().
- No need for negate PTR_ERR to get error code, as crypto_alloc_rng
already returns negative values like ERR_PTR(-ENOMEM). Fixed.
Signed-off-by: Kamil Konieczny <k.konieczny@partner.samsung.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
With the conversion of the kernel crypto API DocBook to Sphinx, the
monolithic document is broken up into individual documents. The
documentation is unchanged with the exception of a slight reordering to
keep the individual document parts self-contained.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>