[openpgp] Backwards compatibility

Paul Wouters <paul@nohats.ca> Wed, 18 October 2023 13:01 UTC

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From: Paul Wouters <paul@nohats.ca>
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Date: Wed, 18 Oct 2023 09:00:17 -0400
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To: Werner Koch <wk@gnupg.org>
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Subject: [openpgp] Backwards compatibility
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> On Oct 18, 2023, at 04:10, Werner Koch <wk@gnupg.org> wrote:
>  Willfully destroying
> backward compatibility

Can you explain in what way the document does this? It tries very hard not to touch older versions so that previously encrypted and signed data can still be validated and fresh communication between older version and newer version clients can still be done using the older version of the protocol.

The new v6 formats drop some dangerous old features but those will only apply to data generated in v6 format.

> and adding extra complexity is not what such deployments need.

But without some “added complexity” those deployments are vulnerable to various real world attacks. The document needed to address those and tried to do so with the least added complexity, discussing these issues at length with multiple vendors.

There is still an IETF Last Call and issues can be raised if we made an error. But you would need to describe the specific issues and the issue with the proposed solution in the document.