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Re: [Cfrg] A little room for AES-192 in TLS?

Joan Daemen <jda@noekeon.org> Tue, 17 January 2017 18:28 UTC

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Date: Tue, 17 Jan 2017 19:28:43 +0100
From: Joan Daemen <jda@noekeon.org>
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References: <20170115205926.853FB60A6D@jupiter.mumble.net> <1484577818.5104.1.camel@quad> <D4A2A7CE.57FDF%john.mattsson@ericsson.com> <CABcZeBPGxT=9iiChy4PxD_zMHWcHU=AhCLoe7wEHHtryw2rfwg@mail.gmail.com> <D4A2B50D.7E040%kenny.paterson@rhul.ac.uk> <CAHOTMVJrHBn4AR7PCJ14xKYCVjdxF7SiswiOABX_g6A5gsQGDg@mail.gmail.com> <1484593651.5104.49.camel@quad> <1df3ba4212e44f9d8e3e6fabf8610cc0@usma1ex-dag1mb1.msg.corp.akamai.com> <1484662079.5135.49.camel@quad> <9d54608c721c465788a38e5cc8e8cac6@usma1ex-dag1mb1.msg.corp.akamai.com> <CACz1E9rZrso0184wiiK04UJnv4sBWZwtM2yYumha08Z-4n0=KQ@mail.gmail.com> <CAHOTMVLGoj7RPFQBTRu_d+kOoBfrKmi+CG+ityyW=x3G4t_AaQ@mail.gmail.com> <CAMm+Lwh05t6AMoRdgmMLZNsAVWAXxax84WOxMB8Cp_gBq5oZVA@mail.gmail.com>
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Subject: Re: [Cfrg] A little room for AES-192 in TLS?
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Dear all,

the related-key attacks against AES were interesting from an academic 
point of view as they broke the security claim we made for Rijndael.

However, the attacks require very sophisticated manipulations of the 
secret key by the attacker. For example, even a protocol that would 
allow an attacker to add (or XOR) a value of her choice to the key 
before being used in AES would not allow mounting the attack. If you are 
interested, you can read the paper Vincent and I wrote "On the 
related-key attacks against AES" available at e.g. 
http://jda.noekeon.org/

As for including AES-192 in TLS, I don't see any benefits.

Kind regards,

Joan Daemen

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