Re: [Ace] Overwriting Tokens

Ludwig Seitz <ludwig.seitz@ri.se> Wed, 12 December 2018 10:05 UTC

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To: Stefanie Gerdes <gerdes@tzi.de>, "ace@ietf.org" <ace@ietf.org>
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From: Ludwig Seitz <ludwig.seitz@ri.se>
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Date: Wed, 12 Dec 2018 11:05:43 +0100
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Subject: Re: [Ace] Overwriting Tokens
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On 12/12/2018 10:33, Stefanie Gerdes wrote:
> Hi again,
> 
> I have one additional comment to ace-oauth-17:
> 
> Section 5.8.1 recommends that RS stores only one token per key and that
> existing tokens are overwritten by new tokens. I wonder how the RS knows
> which token is the most recent. I don't think the expiration time helps
> in this case because it should be possible for the AS to
> provide a token that expires earlier than the previous token.
> 
> 
> Viele Grüße
> Steffi
> 

"Recent" here is meant as "most recently received". That is something 
the RS definitely can track.

/Ludwig

-- 
Ludwig Seitz, PhD
Security Lab, RISE
Phone +46(0)70-349 92 51