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Re: [Cfrg] NSA sabotaging crypto standards

Nikos Mavrogiannopoulos <nmav@gnutls.org> Fri, 07 February 2014 16:12 UTC

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Date: Fri, 07 Feb 2014 17:11:50 +0100
From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
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Subject: Re: [Cfrg] NSA sabotaging crypto standards
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On 02/07/2014 04:59 PM, Watson Ladd wrote:

> But let's go into detail about how well the cryptographers did in TLS.
> In 1995 Phil Rogaway tells everyone to use encrypt-then-MAC.

I believe you are oversimplifying things. Indeed Rogaway suggested
encrypt-then-MAC, but other cryptographers were suggesting
MAC-then-Encrypt (authenticate what is meant not what is sent). There
was also no attack known for MAC-then-encrypt.

In general it is very easy to see the obvious solution 20 years later,
but the challenge is to properly decide at the right time.

regards,
Nikos

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