The current implementation uses a global per-cpu array to store
data which are used to derive the next IV. This is insecure as
the attacker may change the stored data.
This patch removes all traces of chaining and replaces it with
multiplication of the salt and the sequence number.
Fixes: a10f554fa7 ("crypto: echainiv - Add encrypted chain IV...")
Cc: stable@vger.kernel.org
Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now that we no longer have any legacy AEAD implementations the
compatibility code path can no longer be triggered. This patch
removes it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes a bug where we were incorrectly including the
IV in the AD during encryption. The IV must remain in the plain
text for it to be encrypted.
During decryption there is no need to copy the IV to dst because
it's now part of the AD.
This patch removes an unncessary check on authsize which would be
performed by the underlying decrypt call.
Finally this patch makes use of the type-safe init/exit functions.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes the RNG allocation so that we only hold a
reference to the RNG during initialisation.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We currently do the IV seeding on the first givencrypt call in
order to conserve entropy. However, this does not work with
DRBG which cannot be called from interrupt context. In fact,
with DRBG we don't need to conserve entropy anyway. So this
patch moves the seeding into the init function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes a bug in the context size calculation where we
were still referring to the old cra_aead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As the AD does not necessarily exist in the destination buffer
it must be copied along with the plain text.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The cryptoff parameter was added to facilitate the skipping of
IVs that sit between the AD and the plain/cipher text. However,
it was never implemented correctly as and we do not handle users
such as IPsec setting cryptoff. It is simply ignored.
Implementing correctly is in fact more trouble than what it's
worth.
This patch removes the uses of cryptoff and simply falls back
to using the old AEAD interface as it's only needed for old AEAD
implementations.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
New style AEAD instances must use aead_register_instance. This
worked by chance because aead_geniv_alloc is still setting things
the old way.
This patch converts the template over to the create model where
we are responsible for instance registration so that we can call
the correct function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a new AEAD IV generator echainiv. It is intended
to replace the existing skcipher IV generator eseqiv.
If the underlying AEAD algorithm is using the old AEAD interface,
then echainiv will simply use its IV generator.
Otherwise, echainiv will encrypt a counter just like eseqiv but
it'll first xor it against a previously stored IV similar to
chainiv.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
