Re: [openpgp] [RFC4880bis PATCH] WIP: bind wire format representations to specific pubkey algorithms

Daniel Kahn Gillmor <dkg@fifthhorseman.net> Sat, 05 June 2021 17:55 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 797C93A2A97 for <openpgp@ietfa.amsl.com>; Sat, 5 Jun 2021 10:55:06 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.305
X-Spam-Level:
X-Spam-Status: No, score=-1.305 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_DNSWL_BLOCKED=0.001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=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=gq0GO0Qd; dkim=pass (2048-bit key) header.d=fifthhorseman.net header.b=Q7kzas6D
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 vkgbImnGsOKF for <openpgp@ietfa.amsl.com>; Sat, 5 Jun 2021 10:55:01 -0700 (PDT)
Received: from che.mayfirst.org (unknown [162.247.75.117]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 84F393A2A96 for <openpgp@ietf.org>; Sat, 5 Jun 2021 10:55:01 -0700 (PDT)
DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/simple; d=fifthhorseman.net; i=@fifthhorseman.net; q=dns/txt; s=2019; t=1622915700; h=from : to : cc : subject : in-reply-to : references : date : message-id : mime-version : content-type : from; bh=TonyMQPcZSzEDwjAzAUkuexfueDjgNbxSdfKo0bhepM=; b=gq0GO0QdAwJ1D7+SYlry6DUhs5vlbGDRavAnmH+qkhQ/aDU1uYsCjq+ozJ1e4mDS3G/I7 zPTk4mecfzac0V9Bw==
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=fifthhorseman.net; i=@fifthhorseman.net; q=dns/txt; s=2019rsa; t=1622915700; h=from : to : cc : subject : in-reply-to : references : date : message-id : mime-version : content-type : from; bh=TonyMQPcZSzEDwjAzAUkuexfueDjgNbxSdfKo0bhepM=; b=Q7kzas6DBsP0fzhZ7RHt+yIaRgmBeW0AM/Mo6HXmHIOeAcwnnP8/bKB/skt5CpGIhVBFX 8QM5nLavb2x8uRiSfF5302TqjfXIg7etItxFCLNRXYhY4rlx8IUESYoBQNOgkptodJUZ+rN aYzBzDghxCOnW3jToJy6Cgbz6hFr3ysMZIS0qlQeHSzxD/sBQ/KEu1Fn16WbF2K2Detm7fy gHFng8DfYgieENBUcApiDu6QbPabS4xa5vy2fCpOKLwXi959TL8Q+M9KfsSjxolZ/Y5vhFa NafcGt5+saWZoz+dqn60R17Zq+nfWzC9uOMPpihcfs8IL6aDXah5Yy/5+RSQ==
Received: from fifthhorseman.net (ip68-0-212-178.ri.ri.cox.net [68.0.212.178]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by che.mayfirst.org (Postfix) with ESMTPSA id 2E320F9A8; Sat, 5 Jun 2021 13:54:59 -0400 (EDT)
Received: by fifthhorseman.net (Postfix, from userid 1000) id 95A4820824; Sat, 5 Jun 2021 13:31:58 -0400 (EDT)
From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
To: Florian Weimer <fw@deneb.enyo.de>
Cc: IETF OpenPGP WG <openpgp@ietf.org>
In-Reply-To: <87eedg9u4d.fsf@mid.deneb.enyo.de>
References: <20210602230847.3593022-1-dkg@fifthhorseman.net> <87eedg9u4d.fsf@mid.deneb.enyo.de>
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: Sat, 05 Jun 2021 13:31:56 -0400
Message-ID: <871r9grzeb.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/rGo0XNfkQoj6_z643PPzXOpfryE>
Subject: Re: [openpgp] [RFC4880bis PATCH] WIP: bind wire format representations to specific pubkey algorithms
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: Sat, 05 Jun 2021 17:55:07 -0000

Hi Florian--

On Sat 2021-06-05 18:03:14 +0200, Florian Weimer wrote:
> * Daniel Kahn Gillmor:
>
>> The OpenPGP standard is in a bit of a mess when it comes to wire
>> formats for public key algorithms.
>>
>> There are not infrequent reports of interoperability problems (most
>> recently https://dev.gnupg.org/T5464), and difficulties for
>> implementers in understanding what is expected.
>
> I think this issue also affects RSA data because the way OpenPGP
> specifies the operations, they are octet strings of a specific length,
> not integers, and may including leading zero bytes.

This is an unsettling message, but I'm not sure I understand what you
mean.  Can you provide a specific example?

Do you think the text of the draft needs to be updated to clarify RSA as
well?

        --dkg