Re: Online Certificate Revocation Protocol

[pgut001@xxxxxxxxxxxxxxxxx (Peter Gutmann)]

Denis Pinkas <Denis.Pinkas@xxxxxxxx> writes:
>Liaquat,
>
>>I agree a new reason code of ("never valid") has uses.  This will allow a
>>relying party when verifying a digital signatures using a certificate, which
>>when performing revocation checking is found to be on a CRL with the a new
>>reason code ("never valid"), to detect that the digital signature should not
>>be trusted even if the digital signature was produced before the time of the
>>revocation of the certificate.   Otherwise in theory signature produced
>>before the revocation will continue to be considered valid - not a good
>>situation for the relying party or for the CA.
>
>This is the reverse situation. If a signature was tested to be valid e.g. in
>June 2000 and the certificate was revoked for any reason e.g. in May 2001,
>then the signature tested good in June 2000, shall continue to be valid,
>otherwise it would not be a good situation for relying parties.
 
But if the certificate was issued in error then it should (once discovered) be 
marked as never having been valid for any purpose at any time.  Are you saying 
that a bogus cert should be regarded as valid until it was officially revoked?
Does this mean that if I get something signed with one of those bogus 
Microsoft certs I should regard it as coming from MS provided it was signed 
before they were revoked?
 
Peter.