The lskcipher glue code for skcipher needs to copy the IV every
time rather than only on the first and last request. Otherwise
those algorithms that use IV to perform chaining may break, e.g.,
CBC.
This is because crypto_skcipher_import/export do not include the
IV as part of the saved state.
Reported-by: syzbot+b90b904ef6bdfdafec1d@syzkaller.appspotmail.com
Fixes: 662ea18d08 ("crypto: skcipher - Make use of internal state")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When ecb is used to wrap an lskcipher, the statesize isn't set
correctly. Fix this by making the simple instance creator set
the statesize.
Reported-by: syzbot+8ffb0839a24e9c6bfa76@syzkaller.appspotmail.com
Reported-by: Edward Adam Davis <eadavis@qq.com>
Fixes: 662ea18d08 ("crypto: skcipher - Make use of internal state")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds code to the skcipher/lskcipher API to make use
of the internal state if present. In particular, the skcipher
lskcipher wrapper will allocate a buffer for the IV/state and
feed that to the underlying lskcipher algorithm.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Unlike chaining modes such as CBC, stream ciphers other than CTR
usually hold an internal state that must be preserved if the
operation is to be done piecemeal. This has not been represented
in the API, resulting in the inability to split up stream cipher
operations.
This patch adds the basic representation of an internal state to
skcipher and lskcipher. In the interest of backwards compatibility,
the default has been set such that existing users are assumed to
be operating in one go as opposed to piecemeal.
With the new API, each lskcipher/skcipher algorithm has a new
attribute called statesize. For skcipher, this is the size of
the buffer that can be exported or imported similar to ahash.
For lskcipher, instead of providing a buffer of ivsize, the user
now has to provide a buffer of ivsize + statesize.
Each skcipher operation is assumed to be final as they are now,
but this may be overridden with a request flag. When the override
occurs, the user may then export the partial state and reimport
it later.
For lskcipher operations this is reversed. All operations are
not final and the state will be exported unless the FINAL bit is
set. However, the CONT bit still has to be set for the state
to be used.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When an algorithm of the new "lskcipher" type is exposed through the
"skcipher" API, calls to crypto_skcipher_setkey() don't pass on the
CRYPTO_TFM_REQ_FORBID_WEAK_KEYS flag to the lskcipher. This causes
self-test failures for ecb(des), as weak keys are not rejected anymore.
Fix this.
Fixes: 31865c4c4d ("crypto: skcipher - Add lskcipher")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Set the error value to -EINVAL instead of zero when the underlying
name (within "ecb()") fails basic sanity checks.
Fixes: 8aee5d4ebd ("crypto: lskcipher - Add compatibility wrapper around ECB")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202310111323.ZjK7bzjw-lkp@intel.com/
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As an aid to the transition from cipher algorithm implementations
to lskcipher, add a temporary wrapper when creating simple lskcipher
templates by using ecb(X) instead of X if an lskcipher implementation
of X cannot be found.
This can be reverted once all cipher implementations have switched
over to lskcipher.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add a new API type lskcipher designed for taking straight kernel
pointers instead of SG lists. Its relationship to skcipher will
be analogous to that between shash and ahash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Herbert Xu