Re: [TLS] Comments/Questions on draft-gutmann-tls-encrypt-then-mac-00.txt

Peter Gutmann <pgut001@cs.auckland.ac.nz> Wed, 25 September 2013 12:08 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "<tls@ietf.org>" <tls@ietf.org>
Thread-Topic: [TLS] Comments/Questions on draft-gutmann-tls-encrypt-then-mac-00.txt
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Date: Wed, 25 Sep 2013 12:08:42 +0000
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Subject: Re: [TLS] Comments/Questions on draft-gutmann-tls-encrypt-then-mac-00.txt
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Alfredo Pironti <alfredo@pironti.eu> writes:

>Fix is however not too difficult: in the MAC, include the whole
>"plaintext+padding" length, so that it can be computed directly form the
>ciphertext length, without need to decrypt it first.

Oh, I see.  It already is, in fact I'd never even considered that you could do
it any other way, and given the results of the interop tests so far I guess
no-one else has either.  I'll add a clarification to the draft about this.

Peter.