RSA sign/verify and hash generation functions

[Nikos Mavrogiannopoulos]

On 12/08/2010 09:17 PM, Murray S. Kucherawy wrote:
> Here's something interesting I found while trying to figure this out.
> % openssl rsa -in key.pem -text
> Private-Key: (1024 bit)
> modulus:
>     00:b8:19:41:ab:f9:df:fa:48:53:73:54:b6:29:a6:
[...]
> ...and then dumping the modulus and private exponent through code that uses the same format as OpenSSL:> 
> modulus:
>     b8:19:41:ab:f9:df:fa:48:53:73:54:b6:29:a6:19:
> Note that when using GnuTLS, the leading "00" octet in the modulus is missing.
> Is this expected?  Could it explain the different signature I get from
GnuTLS 2.11.6?

The export_raw() functions do not add the leading zero. Adding them
would be better (and I'll modify them to do), but it doesn't explain the
different signature.

regards,
Nikos