pkcs11_sign() reuses *sig to store the header and hash, but those might
be larger than the actual sig, causing a buffer overflow.
An overflow can occur when using raw sigs with hashlen > siglen, or when
the RSA key is less than 664 bits long (or less when using hashes
shorter than SHA512)
As siglen is always within the 'low realm' < 32k, an overflow of asnlen
+ hashlen is not possible.
This restores previous functionality, and thus still allows only RSA to be
used through PKCS#11.
Signed-off-by: Steffan Karger <steffan.karger@fox-it.com>
Signed-off-by: Paul Bakker <p.j.bakker@polarssl.org>
