Re: [TLS] Consensus call on Implicit IV for AEAD

Tom Ritter <tom@ritter.vg> Mon, 06 April 2015 11:25 UTC

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From: Tom Ritter <tom@ritter.vg>
Date: Mon, 6 Apr 2015 06:25:03 -0500
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To: Yoav Nir <ynir.ietf@gmail.com>
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Subject: Re: [TLS] Consensus call on Implicit IV for AEAD
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On 6 April 2015 at 03:41, Yoav Nir <ynir.ietf@gmail.com> wrote:
> So either IVs (actually nonces) are compressible only for such ciphersuites that support using the record counter as nonce/IV (add a flag to the registry), or else we use some method such as AGL's for generating unpredictable IVs from predictable nonces.


Thanks Yoav, ekr,

I obviously haven't followed all the arguments here (and from skimming
Brian's reply) - but I prefer defining a construction that makes the
IV given to the AEAD unpredictable and random. Doing that from a
predictable nonce seems okay.

-tom