RNG quality verification

[Alexander Klimov]

On Thu, 22 Dec 2005, Philipp [iso-8859-1] G?hring wrote:
>
> I have been asked by to verify the quality of the random numbers which are
> used for certificate requests that are being sent to us, to make sure that
> they are good enough, and we don?t issue certificates for weak keys.

Consider an implementation which uses x = time and when
SHA1(hardcoded-string||x), SHA1(hardcoded-string||x+1), etc. as a
starting point to search for primes. Unless you know what is the
hardcoded-string you cannot tell that the random starting point was
not that random: it is very important to realize that randomness is
the property of the source and not of a string.

BTW, note that what you can see in the certificate request for an
RSA key is n and not p and q themselves.

-- 
Regards,
ASK

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