Commit Graph

10 Commits

Author SHA1 Message Date
Eric Biggers
eb772f37ae crypto: salsa20 - export generic helpers
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>
2018-01-12 23:03:42 +11:00
Eric Biggers
b62b3db76f crypto: salsa20-generic - cleanup and convert to skcipher API
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>
2018-01-12 23:03:41 +11:00
Eric Biggers
ecaaab5649 crypto: salsa20 - fix blkcipher_walk API usage
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>
2017-11-29 16:25:58 +11:00
Mathias Krause
3e14dcf7cb crypto: add missing crypto module aliases
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>
2015-01-13 22:29:11 +11:00
Kees Cook
5d26a105b5 crypto: prefix module autoloading with "crypto-"
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>
2014-11-24 22:43:57 +08:00
Jussi Kivilinna
77ec2e734d crypto: cleanup - remove unneeded crypto_alg.cra_list initializations
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>
2012-08-01 17:47:27 +08:00
Harvey Harrison
f0d1ec3a22 crypto: salsa20 - Remove private wrappers around various operations
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>
2008-12-25 11:02:30 +11:00
Kamalesh Babulal
3af5b90bde [CRYPTO] all: Clean up init()/fini()
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>
2008-04-21 10:19:34 +08:00
Tan Swee Heng
eb6f13eb9f [CRYPTO] salsa20_generic: Fix multi-page processing
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>
2008-01-11 08:16:34 +11:00
Tan Swee Heng
2407d60872 [CRYPTO] salsa20: Salsa20 stream cipher
This patch implements the Salsa20 stream cipher using the blkcipher interface.

The core cipher code comes from Daniel Bernstein's submission to eSTREAM:
  http://www.ecrypt.eu.org/stream/svn/viewcvs.cgi/ecrypt/trunk/submissions/salsa20/full/ref/

The test vectors comes from:
  http://www.ecrypt.eu.org/stream/svn/viewcvs.cgi/ecrypt/trunk/submissions/salsa20/full/

It has been tested successfully with "modprobe tcrypt mode=34" on an
UML instance.

Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:15 +11:00