Subject: Re: Dual-signed certificates

From: [email-masked]
Date: Fri, 21 Jul 2000 17:20:26 -0400

Although a certificate with these exact characteristics might not be
feasible, how about a CMS SignedData containing the certificate with an
signedAttribute called "CertificateAccepted" with value GeneralizedTime?
The other alternative would be a self-signed certificate with an
"ExternalCertificate" extension, with a value containing the certificate.
Of course, all these prove is that whoever has the private key agrees that
the certificate is valid - they don't do anything to prove who it is who
has the private key.
     Getting the acceptance itself into the ordinary certificate would not
be feasible.
     However, do people think it appropriate for the real external
certificate to be carried around inside a CMS SignedData or a self-signed
certificate?  It certainly can be done, but should it?

          Tom Gindin

Ben Laurie <[email-masked]> on 07/21/2000 02:27:15 PM

To:   [email-masked]
cc:   [email-masked], [email-masked]
Subject:  Re: Dual-signed certificates

Peter Gutmann wrote:
>
> "Bob Jueneman" <[email-masked]> writes:
>
> >[snip]
> >
> >>Since a certificate is comprised of public information signed by a CA,
> >>clearly a CA can create a certificate saying more-or-less what they
> >>want. I suppose this is an argument for having certificates that are
> >>dual-signed (by the CA and the public key the contain).
>
> >Duh!  Head-slapping!  What a great idea!  I'd love to see this added to
X.509
> >v3 as an optional, noncritical extension.
>
> The chickenAndEgg extension I presume?  How do you process this (or
generate
> it)?

Eh? Or are you referring to the difficulty of having the signature
within the cert? If so, quite!

Cheers,

Ben.

--
http://www.apache-ssl.org/ben.html

Coming to ApacheCon Europe 2000? http://apachecon.com/

---

From: Ben Laurie <[email-masked]>
Date: Sat, 22 Jul 2000 16:39:24 +0100

> the certificate is valid - they don't do anything to prove who it is who

Absolutely, but please don't let's get into the whole identity
discussion again. All I care about is the private key.

>      Getting the acceptance itself into the ordinary certificate would not

Why not?

> certificate?  It certainly can be done, but should it?

The certificate should be extended to carry two signatures, IMO.

Cheers,

Ben.