Re: [openpgp] Backwards compatibility

Werner Koch <> Thu, 19 October 2023 07:14 UTC

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From: Werner Koch <>
To: Paul Wouters <>
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Subject: Re: [openpgp] Backwards compatibility
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On Wed, 18 Oct 2023 14:18, Paul Wouters said:

> Discussion can be found here:

A discussion in commit logs is not a discussion in the WG.  Commit logs
as well as discussions in bug trackers are pretty in-transparent for
participants of the WG because you need to actively monitor all bugs
instead of following the mail threads.

> I'm sure the CFRG would be interested in hearing about GCM attacks.

I don't think the cons of GCM and other counter mopdes need to be

> be used by those who want and those who do not want AES_GCM, and the
> complexity of a code point in addition to EAX and OCB is well, miniscule.

This was the major reason to drop the deployed format and introduce a
the HKDF. 

> I find it hard to believe that all other IETF protocols can safety
> support AES_GCM, but not OpenPGP.

PGP has had always higher standards than committee driven protocols and
tried to do the Right Thing.



The pioneers of a warless world are the youth that
refuse military service.             - A. Einstein