Re: [certid] What security does SRV-ID add when DNS-ID will always match?

Peter Saint-Andre <stpeter@stpeter.im> Wed, 30 March 2011 21:49 UTC

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Date: Wed, 30 Mar 2011 23:51:17 +0200
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Subject: Re: [certid] What security does SRV-ID add when DNS-ID will always match?
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On 3/30/11 11:45 PM, Matt McCutchen wrote:
> On Wed, 2011-03-30 at 23:00 +0200, Peter Saint-Andre wrote:
>> I think that this is a matter of local policy -- a client could prefer
>> SRV-IDs yet still accept DNS-IDs, and as far as I can see that behavior
>> is not expressly forbidden by the spec.
> 
> "Prefer" is vague.  Specifically, I would like the client to accept a
> DNS-ID if and only if the certificate contains no SRV-IDs.  How is this
> accommodated within the framework of the spec?  Clearly the reference
> identifier must contain a DNS-ID. 

Ah, I see the confusion. MUST has been changed to SHOULD in order to be
consistent with what I have called the inclusion approach. If we were to
change over to the conditional approach, we could have left DNS-ID as
MUST, but as I said in my previous message that would have required very
significant changes to the spec during AUTH48.

If you'd like I can post the full list of changes, but it is midnight
here in Prague and I have a lot of preparation to do for tomorrow's
working group sessions, so I simply don't have time right now.

Peter

-- 
Peter Saint-Andre
https://stpeter.im/