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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Jason A. Donenfeld