Subject: RE: OCSP in TLS handshake

From: "Deacon, Alex" <[email-masked]>
Date: Tue, 9 Dec 2003 09:21:37 -0800

nonceUnsupported does not preclude the use of OCSP responses in the TLS
handshake.  My concern was ensuring what ever new text is added to v1
does not preclude this use case.  In particular a client that receives
an ocsp response that includes a nonce in a handshake must not reject
the response because it contains a nonce it didn't generate.  

Alex

> -----Original Message-----
> From: Marc Branchaud [mailto:[email-masked]] 
> Sent: Monday, December 08, 2003 3:59 PM
> To: [email-masked]
> Subject: Re: OCSP in TLS handshake
> 
> 
> Marc Branchaud wrote:
> > 
> > I'm not trying to be obtuse here (it actually takes very little 
> > effort),
> > but I really need a patient explanation of why nonceUnsupported 
> > precludes the use of OCSP responses in the TLS handshake.
> 
> OK, I'd settle for an impatient explanation...
> 
> 		M.
>

---

From: Marc Branchaud <[email-masked]>
Date: Tue, 09 Dec 2003 09:32:55 -0800

> the response because it contains a nonce it didn't generate.  

Thanks, Alex.

In that case, you're not talking about a real OCSP client: the TLS 
client doesn't perform the OCSP protocol.  You say that the (TLS) client 
shouldn't reject the response because of the nonce it didn't generate. 
I agree, but the client never generated an OCSP request, so there was 
never even an opportunity to generate a nonce.  It seems almost obvious 
that the nonce is irrelevant to the TLS client (when the response comes 
from the TLS server embedded in the TLS handshake).

I think it's wrong to equate this TLS client with a regular OCSP client.

Instead of trying to twiddle the OCSP spec to address these sorts of 
issues, I suggest that these (and whatever other) rules be gathered into 
a more general "Offline Processing of OCSP Responses" document.  This 
could be a separate I-D, or a new section in the OCSP (v2?) spec.

		M.

---

From: Marc Branchaud <[email-masked]>
Date: Wed, 10 Dec 2003 09:07:39 -0800

Marc Branchaud wrote:
> 
> In that case, you're not talking about a real OCSP client

Turns out the TLS client can generate a nonce that the TLS server would 
forward to the OCSP server.

Mea culpa.

		M.