Commit Graph

12 Commits

Author SHA1 Message Date
Pan Bian e5bde04ccc crypto: do not free algorithm before using
In multiple functions, the algorithm fields are read after its reference
is dropped through crypto_mod_put. In this case, the algorithm memory
may be freed, resulting in use-after-free bugs. This patch delays the
put operation until the algorithm is never used.

Fixes: 79c65d179a ("crypto: cbc - Convert to skcipher")
Fixes: a7d85e06ed ("crypto: cfb - add support for Cipher FeedBack mode")
Fixes: 043a44001b ("crypto: pcbc - Convert to skcipher")
Cc: <stable@vger.kernel.org>
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-29 14:53:59 +08:00
Marcelo Cerri e6c2e65c70 crypto: cbc - Propagate NEED_FALLBACK bit
When requesting a fallback algorithm, we should propagate the
NEED_FALLBACK bit when search for the underlying algorithm.

This will prevents drivers from allocating unnecessary fallbacks that
are never called. For instance, currently the vmx-crypto driver will use
the following chain of calls when calling the fallback implementation:

p8_aes_cbc -> cbc(p8_aes) -> aes-generic

However p8_aes will always delegate its calls to aes-generic. With this
patch, p8_aes_cbc will be able to use cbc(aes-generic) directly as its
fallback. The same applies to aes_s390.

Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-03-09 18:34:39 +08:00
Ard Biesheuvel db91af0fbe crypto: algapi - make crypto_xor() and crypto_inc() alignment agnostic
Instead of unconditionally forcing 4 byte alignment for all generic
chaining modes that rely on crypto_xor() or crypto_inc() (which may
result in unnecessary copying of data when the underlying hardware
can perform unaligned accesses efficiently), make those functions
deal with unaligned input explicitly, but only if the Kconfig symbol
HAVE_EFFICIENT_UNALIGNED_ACCESS is set. This will allow us to drop
the alignmasks from the CBC, CMAC, CTR, CTS, PCBC and SEQIV drivers.

For crypto_inc(), this simply involves making the 4-byte stride
conditional on HAVE_EFFICIENT_UNALIGNED_ACCESS being set, given that
it typically operates on 16 byte buffers.

For crypto_xor(), an algorithm is implemented that simply runs through
the input using the largest strides possible if unaligned accesses are
allowed. If they are not, an optimal sequence of memory accesses is
emitted that takes the relative alignment of the input buffers into
account, e.g., if the relative misalignment of dst and src is 4 bytes,
the entire xor operation will be completed using 4 byte loads and stores
(modulo unaligned bits at the start and end). Note that all expressions
involving misalign are simply eliminated by the compiler when
HAVE_EFFICIENT_UNALIGNED_ACCESS is defined.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-02-11 17:52:28 +08:00
Herbert Xu cc868d82ab crypto: cbc - Export CBC implementation
This patch moves the core CBC implementation into a header file
so that it can be reused by drivers implementing CBC.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-28 21:23:21 +08:00
Herbert Xu 79c65d179a crypto: cbc - Convert to skcipher
This patch converts cbc over to the skcipher interface.  It also
rearranges the code to allow it to be reused by drivers.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-28 21:23:21 +08:00
Kees Cook 4943ba16bb crypto: include crypto- module prefix in template
This adds the module loading prefix "crypto-" to the template lookup
as well.

For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly
includes the "crypto-" prefix at every level, correctly rejecting "vfat":

	net-pf-38
	algif-hash
	crypto-vfat(blowfish)
	crypto-vfat(blowfish)-all
	crypto-vfat

Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-26 20:06:30 +08:00
David Howells e231c2ee64 Convert ERR_PTR(PTR_ERR(p)) instances to ERR_CAST(p)
Convert instances of ERR_PTR(PTR_ERR(p)) to ERR_CAST(p) using:

perl -spi -e 's/ERR_PTR[(]PTR_ERR[(](.*)[)][)]/ERR_CAST(\1)/' `grep -rl 'ERR_PTR[(]*PTR_ERR' fs crypto net security`

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07 08:42:26 -08:00
Herbert Xu 50b6544e13 [CRYPTO] cbc: Require block size to be a power of 2
All common block ciphers have a block size that's a power of 2.  In fact,
all of our block ciphers obey this rule.

If we require this then CBC can be optimised to avoid an expensive divide
on in-place decryption.

I've also changed the saving of the first IV in the in-place decryption
case to the last IV because that lets us use walk->iv (which is already
aligned) for the xor operation where alignment is required.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:19 +11:00
Herbert Xu 3c7f076da5 [CRYPTO] cbc: Use crypto_xor
This patch replaces the custom xor in CBC with the generic crypto_xor.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:18 +11:00
Herbert Xu ebc610e5bc [CRYPTO] templates: Pass type/mask when creating instances
This patch passes the type/mask along when constructing instances of
templates.  This is in preparation for templates that may support
multiple types of instances depending on what is requested.  For example,
the planned software async crypto driver will use this construct.

For the moment this allows us to check whether the instance constructed
is of the correct type and avoid returning success if the type does not
match.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-05-02 14:38:31 +10:00
Herbert Xu 2e306ee016 [CRYPTO] api: Add type-safe spawns
This patch allows spawns of specific types (e.g., cipher) to be allocated.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-02-07 09:21:01 +11:00
Herbert Xu db131ef908 [CRYPTO] cipher: Added block ciphers for CBC/ECB
This patch adds two block cipher algorithms, CBC and ECB.  These
are implemented as templates on top of existing single-block cipher
algorithms.  They invoke the single-block cipher through the new
encrypt_one/decrypt_one interface.

This also optimises the in-place encryption and decryption to remove
the cost of an IV copy each round.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-09-21 11:44:08 +10:00