Oliver King wrote:
>
> - cipher suites such as DH-RSA-DES-CBC-SHA and DH-DSS-DES-CBC-SHA are _not_
> supported; for these, the Diffie-Hellman parameters form part of the
> server's certificate, and the whole lot has been signed by a CA (using RSA
> or DSA), so the Diffie-Hellman parameters are fixed for sessions using that
> certificate.
>
If my reading of the spec is right its not just the parameters that are
fixed: its the server DH key as well. It uses the term "DH parameters"
somewhat loosely IMHO.
In addition client authentication can involve a DH certificate which
must use the same parameters. This appears to have the somewhat
undesirable additional consequence that the pre-master secret is always
the same for a fixed server and client both using fixed DH certificates.
Steve.
--
Dr Stephen N. Henson. http://www.drh-consultancy.demon.co.uk/
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