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Re: [TLS] Data limit for GCM under a given key.

Dave Garrett <davemgarrett@gmail.com> Sat, 07 November 2015 02:39 UTC

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From: Dave Garrett <davemgarrett@gmail.com>
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Date: Fri, 06 Nov 2015 21:39:10 -0500
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Subject: Re: [TLS] Data limit for GCM under a given key.
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On Friday, November 06, 2015 08:13:44 pm Eric Rescorla wrote:
> Update: we discussed this extensively in Yokohama and based on Watson's
> feedback and offline comments from David McGrew, the consensus was that we
> needed to add some sort of rekeying mechanism to support long-lived flows.
> Expect a PR on this next week.
> 
> Note: We'll still need guidance to implementations on when to re-key, but
> we don't expect to have a hard protocol limit.

If re-keying is back up for discussion, let me restate my request for it to be routine, rather than only an niche-case feature. Any re-key schedule should be considered valid, but the spec should set a "SHOULD"-level requirement that the minimum be once every N hours or M terabytes, whichever comes first (where N & M are some bike-shedable numbers with some expectation of randomization in values for each period).


Dave

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