Commit graph

16 commits

Author SHA1 Message Date
Jia-Ju Bai
1ca2809897 crypto: rsa-pkcs1pad - Replace GFP_ATOMIC with GFP_KERNEL in pkcs1pad_encrypt_sign_complete
After checking all possible call chains to kzalloc here,
my tool finds that this kzalloc is never called in atomic context.
Thus GFP_ATOMIC is not necessary, and it can be replaced with GFP_KERNEL.

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-02-15 23:26:47 +08:00
Gilad Ben-Yossef
4e5b0ad582 crypto: remove redundant backlog checks on EBUSY
Now that -EBUSY return code only indicates backlog queueing
we can safely remove the now redundant check for the
CRYPTO_TFM_REQ_MAY_BACKLOG flag when -EBUSY is returned.

Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-03 22:11:17 +08:00
Jason A. Donenfeld
fec17cb223 crypto: rsa-pkcs1pad - use constant time memory comparison for MACs
Otherwise, we enable all sorts of forgeries via timing attack.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Suggested-by: Stephan Müller <smueller@chronox.de>
Cc: stable@vger.kernel.org
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-06-20 11:21:19 +08:00
Tudor-Dan Ambarus
543de102e3 crypto: pkcs1pad - comply with crypto_akcipher_maxsize()
crypto_akcipher_maxsize() asks for the output buffer size without
caring for errors. It allways assume that will be called after
a valid setkey. Comply with it and return what he wants.

crypto_akcipher_maxsize() now returns an unsigned int.
Remove the unnecessary check.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-06-10 12:04:31 +08:00
Herbert Xu
0cf43f509f crypto: rsa-pkcs1pad - Handle leading zero for decryption
As the software RSA implementation now produces fixed-length
output, we need to eliminate leading zeros in the calling code
instead.

This patch does just that for pkcs1pad decryption while signature
verification was fixed in an earlier patch.

Fixes: 9b45b7bba3 ("crypto: rsa - Generate fixed-length output")
Reported-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-09-22 17:42:08 +08:00
Tadeusz Struk
a6d7bfd0ff crypto: rsa-pkcs1pad - fix rsa-pkcs1pad request struct
To allow for child request context the struct akcipher_request child_req
needs to be at the end of the structure.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-19 12:01:47 +08:00
Herbert Xu
27710b8ea3 crypto: rsa-pkcs1pad - Fix regression from leading zeros
As the software RSA implementation now produces fixed-length
output, we need to eliminate leading zeros in the calling code
instead.

This patch does just that for pkcs1pad signature verification.

Fixes: 9b45b7bba3 ("crypto: rsa - Generate fixed-length output")
Reported-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-03 15:44:56 +08:00
Herbert Xu
d858b07138 crypto: rsa-pkcs1pad - Avoid copying output when possible
In the vast majority of cases (2^-32 on 32-bit and 2^-64 on 64-bit)
cases, the result from encryption/signing will require no padding.

This patch makes these two operations write their output directly
to the final destination.  Only in the exceedingly rare cases where
fixup is needed to we copy it out and back to add the leading zeroes.

This patch also makes use of the crypto_akcipher_set_crypt API
instead of writing the akcipher request directly.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-01 23:45:20 +08:00
Herbert Xu
73f7918960 crypto: rsa-pkcs1pad - Move key size check to setkey
Rather than repeatedly checking the key size on each operation,
we should be checking it once when the key is set.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-01 23:45:20 +08:00
Herbert Xu
3a32ce507a crypto: rsa-pkcs1pad - Always use GFP_KERNEL
We don't currently support using akcipher in atomic contexts,
so GFP_KERNEL should always be used.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-01 23:45:19 +08:00
Herbert Xu
0f2c83190b crypto: rsa-pkcs1pad - Remove bogus page splitting
The helper pkcs1pad_sg_set_buf tries to split a buffer that crosses
a page boundary into two SG entries.  This is unnecessary.  This
patch removes that.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-01 23:45:19 +08:00
Herbert Xu
c0d20d22e0 crypto: rsa-pkcs1pad - Require hash to be present
The only user of rsa-pkcs1pad always uses the hash so there is
no reason to support the case of not having a hash.

This patch also changes the digest info lookup so that it is
only done once during template instantiation rather than on each
operation.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-01 23:45:19 +08:00
Tadeusz Struk
6f0904ada4 crypto: rsa-pkcs1pad - fix dst len
The output buffer length has to be at least as big as the key_size.
It is then updated to the actual output size by the implementation.

Cc: <stable@vger.kernel.org>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-15 22:13:55 +08:00
Tadeusz Struk
a49de377e0 crypto: Add hash param to pkcs1pad
This adds hash param to pkcs1pad.
The pkcs1pad template can work with or without the hash.
When hash param is provided then the verify operation will
also verify the output against the known digest.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-03 21:49:26 +00:00
Andrzej Zaborowski
5319216dcf crypto: rsa-pkcs1pad - don't allocate buffer on stack
Avoid the s390 compile "warning: 'pkcs1pad_encrypt_sign_complete'
uses dynamic stack allocation" reported by kbuild test robot.  Don't
use a flat zero-filled buffer, instead zero the contents of the SGL.

Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-12-22 20:43:24 +08:00
Andrzej Zaborowski
3d5b1ecdea crypto: rsa - RSA padding algorithm
This patch adds PKCS#1 v1.5 standard RSA padding as a separate template.
This way an RSA cipher with padding can be obtained by instantiating
"pkcs1pad(rsa)".  The reason for adding this is that RSA is almost
never used without this padding (or OAEP) so it will be needed for
either certificate work in the kernel or the userspace, and I also hear
that it is likely implemented by hardware RSA in which case hardware
implementations of the whole of pkcs1pad(rsa) can be provided.

Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-12-09 20:03:57 +08:00