Re: [openpgp] AEAD mode unverified chunks

Peter Gutmann <pgut001@cs.auckland.ac.nz> Sun, 01 July 2018 06:53 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Marcus Brinkmann <marcus.brinkmann=40ruhr-uni-bochum.de@dmarc.ietf.org>, IETF OpenPGP <openpgp@ietf.org>
Thread-Topic: [openpgp] AEAD mode unverified chunks
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Date: Sun, 01 Jul 2018 06:53:46 +0000
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Subject: Re: [openpgp] AEAD mode unverified chunks
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Marcus Brinkmann <marcus.brinkmann=40ruhr-uni-bochum.de@dmarc.ietf.org> writes:

>If a chunk can not be authenticated, implementations MUST discard the
>plaintext without further processing.  Unauthenticated plaintext MUST not be
>output to other applications or the user.

Unfortunately it's nowhere near as simple as that, in general, this is an
unsolveable problem.  See:

https://tools.ietf.org/html/rfc6476#section-6

for a discussion.

Peter.