[openpgp] Deprecate non-integrity-protected encryption

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

Return-Path: <neal@walfield.org>
X-Original-To: openpgp@ietfa.amsl.com
Delivered-To: openpgp@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 2BB213A1420 for <openpgp@ietfa.amsl.com>; Fri, 26 Feb 2021 04:08:57 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.899
X-Spam-Level:
X-Spam-Status: No, score=-1.899 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_NONE=0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id a5WJswhaUf0I for <openpgp@ietfa.amsl.com>; Fri, 26 Feb 2021 04:08:55 -0800 (PST)
Received: from mail.dasr.de (mail.dasr.de [217.69.77.164]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 501103A141E for <openpgp@ietf.org>; Fri, 26 Feb 2021 04:08:55 -0800 (PST)
Received: from p5de92c26.dip0.t-ipconnect.de ([93.233.44.38] helo=forster.huenfield.org) by mail.dasr.de with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.86_2) (envelope-from <neal@walfield.org>) id 1lFbvR-0003m5-RX; Fri, 26 Feb 2021 12:08:53 +0000
Received: from grit.huenfield.org ([192.168.20.9] helo=grit.walfield.org) by forster.huenfield.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from <neal@walfield.org>) id 1lFbvR-00021O-BY; Fri, 26 Feb 2021 13:08:53 +0100
Date: Fri, 26 Feb 2021 13:08:53 +0100
Message-ID: <87eeh3av56.wl-neal@walfield.org>
From: "Neal H. Walfield" <neal@walfield.org>
To: Paul Wouters <paul@nohats.ca>
Cc: openpgp@ietf.org
In-Reply-To: <7d8bdda1-4e5c-6c10-f3cd-1d191fad595c@nohats.ca>
References: <7d8bdda1-4e5c-6c10-f3cd-1d191fad595c@nohats.ca>
User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM/1.14.9 (Gojō) APEL/10.8 EasyPG/1.0.0 Emacs/26 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO)
MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue")
Content-Type: text/plain; charset="US-ASCII"
X-SA-Exim-Connect-IP: 192.168.20.9
X-SA-Exim-Mail-From: neal@walfield.org
X-SA-Exim-Scanned: No (on forster.huenfield.org); SAEximRunCond expanded to false
Archived-At: <https://mailarchive.ietf.org/arch/msg/openpgp/YHUY2hiNcV0wsnOv15ftPJMh4Pk>
Subject: [openpgp] Deprecate non-integrity-protected encryption
X-BeenThere: openpgp@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Ongoing discussion of OpenPGP issues." <openpgp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/openpgp>, <mailto:openpgp-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/openpgp/>
List-Post: <mailto:openpgp@ietf.org>
List-Help: <mailto:openpgp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/openpgp>, <mailto:openpgp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 26 Feb 2021 12:08:57 -0000

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