[openpgp] Deprecate non-integrity-protected encryption

"Neal H. Walfield" <neal@walfield.org> Fri, 26 February 2021 12:08 UTC

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Date: Fri, 26 Feb 2021 13:08:53 +0100
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From: "Neal H. Walfield" <neal@walfield.org>
To: Paul Wouters <paul@nohats.ca>
Cc: openpgp@ietf.org
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Subject: [openpgp] Deprecate non-integrity-protected encryption
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On Tue, 23 Feb 2021 03:19:03 +0100,
Paul Wouters wrote:
> - Deprecate non-integrity-protected encryption

  +This packet is obsolete.
  +An implementation MUST NOT create this packet.
  +An implementation MAY process such a packet but it MUST return a clear diagnostic that a non-integrity protected packet has been processed.
  +The implementation SHOULD also return an error in this case and stop processing.

It's not clear to me how a library should warn the user.  In Sequoia,
an application has to opt-in to deprecated algorithms.  Is that
enough?


I'm also confused about the interplay between the last two sentences:
in the second-to-last sentence, an implementation "MAY process such a
packet" and in the last it "SHOULD *also* ... stop processing" (stars
mine).  Aren't these in conflict?

:) Neal