Re: [openpgp] Remove session key checksum and padding for v6 ECDH

Daniel Kahn Gillmor <dkg@fifthhorseman.net> Fri, 03 March 2023 19:34 UTC

Return-Path: <dkg@fifthhorseman.net>
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 4C61CC151557 for <openpgp@ietfa.amsl.com>; Fri, 3 Mar 2023 11:34:02 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.303
X-Spam-Level:
X-Spam-Status: No, score=-1.303 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001, URIBL_DBL_BLOCKED_OPENDNS=0.001, URIBL_ZEN_BLOCKED_OPENDNS=0.001] autolearn=no autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=neutral reason="invalid (unsupported algorithm ed25519-sha256)" header.d=fifthhorseman.net header.b="i/CCsTN7"; dkim=pass (2048-bit key) header.d=fifthhorseman.net header.b="XiMZMQs1"
Received: from mail.ietf.org ([50.223.129.194]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id U8vPoMfA3pWS for <openpgp@ietfa.amsl.com>; Fri, 3 Mar 2023 11:33:57 -0800 (PST)
Received: from che.mayfirst.org (unknown [162.247.75.117]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id B13DFC14CF1D for <openpgp@ietf.org>; Fri, 3 Mar 2023 11:33:57 -0800 (PST)
DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/simple; d=fifthhorseman.net; i=@fifthhorseman.net; q=dns/txt; s=2019; t=1677872036; h=from : to : subject : in-reply-to : references : date : message-id : mime-version : content-type : from; bh=xRStv5kWqYUDFFpnEHCiqOADtyEwE2Vg3x2RorZlXEE=; b=i/CCsTN7togwm5zUuOa/P0ZRZ5K8nHKL5S6pEcH+0imq4SHwaEGAp2YfXksW6Qy9cx/gW l3TmJyTlT153XvvDQ==
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=fifthhorseman.net; i=@fifthhorseman.net; q=dns/txt; s=2019rsa; t=1677872036; h=from : to : subject : in-reply-to : references : date : message-id : mime-version : content-type : from; bh=xRStv5kWqYUDFFpnEHCiqOADtyEwE2Vg3x2RorZlXEE=; b=XiMZMQs1qnUgcPMxfnZOlue5Qwy/d9E2BrdW2r/O7f0o9XGqpXy1+DYKPiMEvzFnrlhND EbEeqYS1gcOJS2XmYoeBWyhspVFJWkKYQvsl72rRz/TeGZqsPoFIqr3cs9pvfjmGMtdtEXM m94mMbvxCfZCNYCzQpGnpmmX5Rj0dJCCXoGEKD9xQ64koVd5Px+nqz+knRqCzxdcO/rL6LO PlVX1KghWQJwoSRb39bpu9z8iQYrK9um60oS90zm9fk3pkMtY7vnC6DsdTopT6p1fmkBF2Q zYVeJ6//AgNLz5CpXllRGQMjO3waZ4hmwb4VKfc2SI9xH0LH4BqAk63L4/LA==
Received: from fifthhorseman.net (lair.fifthhorseman.net [108.58.6.98]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384)) (No client certificate requested) by che.mayfirst.org (Postfix) with ESMTPSA id 62C15F9AD for <openpgp@ietf.org>; Fri, 3 Mar 2023 14:33:56 -0500 (EST)
Received: by fifthhorseman.net (Postfix, from userid 1000) id 8053A20328; Fri, 3 Mar 2023 14:33:47 -0500 (EST)
From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
To: openpgp@ietf.org
In-Reply-To: <87sfeuu2xd.fsf@fifthhorseman.net>
References: <87sfeuu2xd.fsf@fifthhorseman.net>
Autocrypt: addr=dkg@fifthhorseman.net; prefer-encrypt=mutual; keydata= mDMEX+i03xYJKwYBBAHaRw8BAQdACA4xvL/xI5dHedcnkfViyq84doe8zFRid9jW7CC9XBiI0QQf FgoAgwWCX+i03wWJBZ+mAAMLCQcJEOCS6zpcoQ26RxQAAAAAAB4AIHNhbHRAbm90YXRpb25zLnNl cXVvaWEtcGdwLm9yZ/tr8E9NA10HvcAVlSxnox6z62KXCInWjZaiBIlgX6O5AxUKCAKbAQIeARYh BMKfigwB81402BaqXOCS6zpcoQ26AADZHQD/Zx9nc3N2kj13AUsKMr/7zekBtgfSIGB3hRCU74Su G44A/34Yp6IAkndewLxb1WdRSokycnaCVyrk0nb4imeAYyoPtBc8ZGtnQGZpZnRoaG9yc2VtYW4u bmV0PojRBBMWCgCDBYJf6LTfBYkFn6YAAwsJBwkQ4JLrOlyhDbpHFAAAAAAAHgAgc2FsdEBub3Rh dGlvbnMuc2VxdW9pYS1wZ3Aub3JnL0Gwxvypz2tu1IPG+yu1zPjkiZwpscsitwrVvzN3bbADFQoI ApsBAh4BFiEEwp+KDAHzXjTYFqpc4JLrOlyhDboAAPkXAP0Z29z7jW+YzLzPTQML4EQLMbkHOfU4 +s+ki81Czt0WqgD/SJ8RyrqDCtEP8+E4ZSR01ysKqh+MUAsTaJlzZjehiQ24MwRf6LTfFgkrBgEE AdpHDwEBB0DkKHOW2kmqfAK461+acQ49gc2Z6VoXMChRqobGP0ubb4kBiAQYFgoBOgWCX+i03wWJ BZ+mAAkQ4JLrOlyhDbpHFAAAAAAAHgAgc2FsdEBub3RhdGlvbnMuc2VxdW9pYS1wZ3Aub3Jnfvo+ nHoxDwaLaJD8XZuXiaqBNZtIGXIypF1udBBRoc0CmwICHgG+oAQZFgoAbwWCX+i03wkQPp1xc3He VlxHFAAAAAAAHgAgc2FsdEBub3RhdGlvbnMuc2VxdW9pYS1wZ3Aub3JnaheiqE7Pfi3Atb3GGTw+ jFcBGOaobgzEJrhEuFpXREEWIQQttUkcnfDcj0MoY88+nXFzcd5WXAAAvrsBAIJ5sBg8Udocv25N stN/zWOiYpnjjvOjVMLH4fV3pWE1AP9T6hzHz7hRnAA8d01vqoxOlQ3O6cb/kFYAjqx3oMXSBhYh BMKfigwB81402BaqXOCS6zpcoQ26AADX7gD/b83VObe14xrNP8xcltRrBZF5OE1rQSPkMNy+eWpk eCwA/1hxiS8ZxL5/elNjXiWuHXEvUGnRoVj745Vl48sZPVYMuDgEX+i03xIKKwYBBAGXVQEFAQEH QIGex1WZbH6xhUBve5mblScGYU+Y8QJOomXH+rr5tMsMAwEICYjJBBgWCgB7BYJf6LTfBYkFn6YA CRDgkus6XKENukcUAAAAAAAeACBzYWx0QG5vdGF0aW9ucy5zZXF1b2lhLXBncC5vcmcEAx9vTD3b J0SXkhvcRcCr6uIDJwic3KFKxkH1m4QW0QKbDAIeARYhBMKfigwB81402BaqXOCS6zpcoQ26AAAX mwD8CWmukxwskU82RZLMk5fm1wCgMB5z8dA50KLw3rgsCykBAKg1w/Y7XpBS3SlXEegIg1K1e6dR fRxL7Z37WZXoH8AH
Date: Fri, 03 Mar 2023 14:33:46 -0500
Message-ID: <87wn3xpr39.fsf@fifthhorseman.net>
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="=-=-="; micalg="pgp-sha256"; protocol="application/pgp-signature"
Archived-At: <https://mailarchive.ietf.org/arch/msg/openpgp/kK2LvcHIOn6UkjZqi36VQEgkgoY>
Subject: Re: [openpgp] Remove session key checksum and padding for v6 ECDH
X-BeenThere: openpgp@ietf.org
X-Mailman-Version: 2.1.39
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, 03 Mar 2023 19:34:02 -0000

On Fri 2023-02-24 17:14:06 -0500, Daniel Kahn Gillmor wrote:
> in https://gitlab.com/openpgp-wg/rfc4880bis/-/merge_requests/223 we have
> a proposal to remove the checksum and padding steps for ECDH when used
> with v6 PKESK:
>
>    https://mailarchive.ietf.org/arch/msg/openpgp/em4s5PL9GO7EUrigDbQdc8TOP9c

It's been almost a full week and no one has weighed in on this proposal
at all.  This change modifies how keys are derived and stored on the
wire for v6 ECDH, so it is a substantial change.

In order to adopt this change at this point in the cycle, i think we'd
need at least some public advocacy for it, as well as some clear
concurrence, with no strong objections from any active implementer.

Given the lack of feedback here, i'm inclined to say that this doesn't
have the consensus of the group.

     --dkg