Subject: RE: OCSPv1 and nonces (RE: draft meeting minutes)

From: "Ryan M. Hurst" <[email-masked]>
Date: Tue, 18 Nov 2003 22:29:45 -0800

Stephen - I agree with what you have written, however the statement in question does not say that a client "SHOULD" or ought to reject it, it mandates it my specifying it as a "MUST".
 
Since it is the client that requests the nonce and is the only one who benefits from when it is used, it should be up to the client to decide what to do with the response with or without it.
 
Ryan

________________________________

From: [email-masked] on behalf of Stephen Kent
Sent: Tue 11/18/2003 4:10 PM
To: Deacon, Alex
Cc: [email-masked]
Subject: Re: OCSPv1 and nonces (RE: draft meeting minutes)

At 14:44 -0800 11/18/03, Deacon, Alex wrote:
>Hi,
>
>I was surprised to read about the decision made at the PKIX meeting last
>week in MN regarding the action to update OCSPv1 to require servers to
>include the nonce in the response or return an error.  (See excerpts below
>from both the draft minutes sent by Steve and from the WG summary sent by
>Tim)
>
>Let me summarize the reasons I feel this decision is a bad idea:
>
>1) It will cause currently conformant OCSPv1 implementations to be
>non-conformant.
>
>2) It will cause OCSP profiles defined in other standards bodies to be
>non-conformant.  
>
>3) It seems to be contrary to the "rough consensus" I thought was clear
>based on the various polls Mike Myers posted to the list on this subject in
>mid October.
>
>Its to late in the game to make such a large change to basic OCSPv1
>behavior.  Keep OCSPv1 as it is.
>

Alex,

There is a clear feeling that when a server returns a canned
(nonceless) response to a client request that included a nonce, that
this is not conforming to the spirit of OCSP, even if the RFC did not
spell out this case in excruciating detail. Russ Housely reaffirmed
this in the quote I included in the minutes.

The question of what a server should do when it receives a request
with a nonce and is unable to comply is still up in the air, in my
opinion.  The list has discussed the merits and shortcomings of
having a server send an (unsigned) error message. Not sending any
response is certainly another option. A good fix to this problem may
have to await a revision of OCSP. But, in any case, a client that
sent a request with a nonce ought to reject a canned response, as
Russ said.

I don't see this clarification as changing the OCSPv1 spec.
Moreover, my reading of the responses to Mike's poll suggests that
the vast majority of servers and clients operate in an appropriate
manner in this regard, given the level of guidance provided in the
RFC.

There is no suggestion here that servers that issue only canned
responses are  bad. OCSP specifically allows for canned responses.
The issue is that a server should not issue a canned response to a
request that clearly requests a response that contains a nonce.

Steve

---

From: "Miguel Rodriguez" <[email-masked]>
Date: Wed, 19 Nov 2003 09:43:00 -0600

My understanding about the poll is that is was about how many client
implementations would break as a consequence of the normative:
 
"Clients that elect to include a request nonce
     SHALL reject responses that fail to include
     the client's nonce from the associated request."
 
   "Correspondingly, upon receipt of a request
     containing a nonce, a responder SHALL include
     the value of such nonce in the production of
     the associated response."
 
A majority responded "no breakage". After that the discussion turned to
the point Ryan mentions, that is, how clients can decide what to do when
receiving a nonceless response to a request with a nonce. There were
several proposals here, but this was not the purpose of the poll. Of
course one possibility is to always reject such responses. I think our
discussion, and the attention it got, showed that this issue is
important to the PKI community. I'd like to continue the discussion,
since we were getting good proposals.
 
My two cents,
 
Miguel A Rodriguez
SeguriDATA
Mexico
 
-----Original Message-----
From: [email-masked] [mailto:[email-masked]]
On Behalf Of Ryan M. Hurst
Sent: Wednesday, November 19, 2003 12:30 AM
To: Stephen Kent; Deacon, Alex
Cc: [email-masked]
Subject: RE: OCSPv1 and nonces (RE: draft meeting minutes)
 
Stephen - I agree with what you have written, however the statement in
question does not say that a client "SHOULD" or ought to reject it, it
mandates it my specifying it as a "MUST".
 
Since it is the client that requests the nonce and is the only one who
benefits from when it is used, it should be up to the client to decide
what to do with the response with or without it.
 
Ryan
 
  _____  

Alex,

Steve