If the user-provided IV needs to be aligned to the algorithm's
alignmask, then skcipher_walk_virt() copies the IV into a new aligned
buffer walk.iv. But skcipher_walk_virt() can fail afterwards, and then
if the caller unconditionally accesses walk.iv, it's a use-after-free.
salsa20-generic doesn't set an alignmask, so currently it isn't affected
by this despite unconditionally accessing walk.iv. However this is more
subtle than desired, and it was actually broken prior to the alignmask
being removed by commit b62b3db76f ("crypto: salsa20-generic - cleanup
and convert to skcipher API").
Since salsa20-generic does not update the IV and does not need any IV
alignment, update it to use req->iv instead of walk.iv.
Fixes: 2407d60872 ("[CRYPTO] salsa20: Salsa20 stream cipher")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In salsa20_docrypt(), use crypto_xor_cpy() instead of crypto_xor().
This avoids having to memcpy() the src buffer to the dst buffer.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
salsa20-generic doesn't use SIMD instructions or otherwise disable
preemption, so passing atomic=true to skcipher_walk_virt() is
unnecessary.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This reverts commit eb772f37ae, as now the
x86 Salsa20 implementation has been removed and the generic helpers are
no longer needed outside of salsa20_generic.c.
We could keep this just in case someone else wants to add a new
optimized Salsa20 implementation. But given that we have ChaCha20 now
too, I think it's unlikely. And this can always be reverted back.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Export the Salsa20 constants, transform context, and initialization
functions so that they can be reused by the x86 implementation.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Convert salsa20-generic from the deprecated "blkcipher" API to the
"skcipher" API, in the process fixing it up to be thread-safe (as the
crypto API expects) by maintaining each request's state separately from
the transform context.
Also remove the unnecessary cra_alignmask and tighten validation of the
key size by accepting only 16 or 32 bytes, not anything in between.
These changes bring the code close to the way chacha20-generic does
things, so hopefully it will be easier to maintain in the future.
However, the way Salsa20 interprets the IV is still slightly different;
that was not changed.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When asked to encrypt or decrypt 0 bytes, both the generic and x86
implementations of Salsa20 crash in blkcipher_walk_done(), either when
doing 'kfree(walk->buffer)' or 'free_page((unsigned long)walk->page)',
because walk->buffer and walk->page have not been initialized.
The bug is that Salsa20 is calling blkcipher_walk_done() even when
nothing is in 'walk.nbytes'. But blkcipher_walk_done() is only meant to
be called when a nonzero number of bytes have been provided.
The broken code is part of an optimization that tries to make only one
call to salsa20_encrypt_bytes() to process inputs that are not evenly
divisible by 64 bytes. To fix the bug, just remove this "optimization"
and use the blkcipher_walk API the same way all the other users do.
Reproducer:
#include <linux/if_alg.h>
#include <sys/socket.h>
#include <unistd.h>
int main()
{
int algfd, reqfd;
struct sockaddr_alg addr = {
.salg_type = "skcipher",
.salg_name = "salsa20",
};
char key[16] = { 0 };
algfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
bind(algfd, (void *)&addr, sizeof(addr));
reqfd = accept(algfd, 0, 0);
setsockopt(algfd, SOL_ALG, ALG_SET_KEY, key, sizeof(key));
read(reqfd, key, sizeof(key));
}
Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: eb6f13eb9f ("[CRYPTO] salsa20_generic: Fix multi-page processing")
Cc: <stable@vger.kernel.org> # v2.6.25+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit 5d26a105b5 ("crypto: prefix module autoloading with "crypto-"")
changed the automatic module loading when requesting crypto algorithms
to prefix all module requests with "crypto-". This requires all crypto
modules to have a crypto specific module alias even if their file name
would otherwise match the requested crypto algorithm.
Even though commit 5d26a105b5 added those aliases for a vast amount of
modules, it was missing a few. Add the required MODULE_ALIAS_CRYPTO
annotations to those files to make them get loaded automatically, again.
This fixes, e.g., requesting 'ecb(blowfish-generic)', which used to work
with kernels v3.18 and below.
Also change MODULE_ALIAS() lines to MODULE_ALIAS_CRYPTO(). The former
won't work for crypto modules any more.
Fixes: 5d26a105b5 ("crypto: prefix module autoloading with "crypto-"")
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:
https://lkml.org/lkml/2013/3/4/70
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Initialization of cra_list is currently mixed, most ciphers initialize this
field and most shashes do not. Initialization however is not needed at all
since cra_list is initialized/overwritten in __crypto_register_alg() with
list_add(). Therefore perform cleanup to remove all unneeded initializations
of this field in 'crypto/'.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ROTATE -> rol32
XOR was always used with the same destination, use ^=
PLUS/PLUSONE use ++ or +=
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On Thu, Mar 27, 2008 at 03:40:36PM +0100, Bodo Eggert wrote:
> Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> wrote:
>
> > This patch cleanups the crypto code, replaces the init() and fini()
> > with the <algorithm name>_init/_fini
>
> This part ist OK.
>
> > or init/fini_<algorithm name> (if the
> > <algorithm name>_init/_fini exist)
>
> Having init_foo and foo_init won't be a good thing, will it? I'd start
> confusing them.
>
> What about foo_modinit instead?
Thanks for the suggestion, the init() is replaced with
<algorithm name>_mod_init ()
and fini () is replaced with <algorithm name>_mod_fini.
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes the multi-page processing bug that affects large test
vectors (the same bug that previously affected ctr.c).
There is an optimization for the case walk.nbytes == nbytes. Also we
now use crypto_xor() instead of adhoc XOR routines.
Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
