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Re: [openpgp] "OpenPGP Simple"

Peter Gutmann <pgut001@cs.auckland.ac.nz> Tue, 17 March 2015 08:18 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "openpgp@ietf.org" <openpgp@ietf.org>
Thread-Topic: [openpgp] "OpenPGP Simple"
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Date: Tue, 17 Mar 2015 08:17:35 +0000
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Subject: Re: [openpgp] "OpenPGP Simple"
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Jon Callas <jon@callas.org> writes:

>But when you do, take into account that MDC pre-dates HMAC 

"Implementation of Chosen-Ciphertext Attacks against PGP and GnuPG" was
published at ISC'02, the MDC mechanism appeared in OpenPGP drafts around
2000-2001.  "Keying Hash Functions for Message Authentication" dates from
1996, predating even the original OpenPGP spec (RFC 2440 from 1998, which
doesn't mention MDC).

>Standards are compromises, and a good compromise leaves everyone a bit
>grumpy. Since those days, I’ve developed an affection for MDC because it sits
>in a nether world where related concepts like deniable encryption that also
>sound good until you think about them for long enough.

See "The Order of Encryption and Authentication for Protecting Communications
(Or: How Secure is SSL?)?" from Crypto'01.

Peter.

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