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Re: [MLS] Unpredictable epochs?

Benjamin Beurdouche <benjamin.beurdouche@inria.fr> Fri, 26 April 2019 14:10 UTC

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From: Benjamin Beurdouche <benjamin.beurdouche@inria.fr>
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Date: Fri, 26 Apr 2019 16:10:08 +0200
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To: Richard Barnes <rlb@ipv.sx>
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Subject: Re: [MLS] Unpredictable epochs?
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> On Apr 26, 2019, at 3:21 PM, Richard Barnes <rlb@ipv.sx> wrote:
> 
> We might have a problem in any case, then, since the transcript hash doesn't cover the signatures either.
> 

Ok, there might be an issue then, I am quite sure that it was covered at some
point, so it might have been lost. The slight difference with TLS is that some
messages can be discarded from processing (add_send/receive_current_member
or add_send/receive_new_member) while I expect that all of the messages must
somehow be contributed to the transcript-hash to provide the strongest authentication
properties. I’ll have a look into this...

B.

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