Re: [TLS] [pkix] Possible revocation delay issue with TLS stapling

"Kemp, David P." <DPKemp@missi.ncsc.mil> Mon, 29 March 2010 13:54 UTC

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Date: Mon, 29 Mar 2010 09:54:33 -0400
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From: "Kemp, David P." <DPKemp@missi.ncsc.mil>
To: <pkix@ietf.org>, <tls@ietf.org>
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Subject: Re: [TLS] [pkix] Possible revocation delay issue with TLS stapling
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That only gets you halfway there, since the nonce only ensures freshness
back to the OCSP responder, not the revocation authority.  The responder
itself can get revocation updates using any of the strategies you
mentioned (on every query - e.g. database backend, only after CRL
nextUpdate, somewhere in between, only after somewhere beyond
nextUpdate). 

If you *really, really* care, insist on CRLs.  But that would require
reasonable-sized CRLs (10Kb) with reasonably short nextUpdate (24h),
neither of which DoD currently produces.

It would also help to have a low-overhead (UDP-based with DTLS symmetric
integrity) CRL query protocol with an "I have this one, send me a newer
one if it exists" semantics.

Dave


-----Original Message-----
From: Miller, Timothy J

Which throws us back on "If you *really* care, insist on nonces."