IETF Logo Mail Archive

Re: [openpgp] Reducing the meta-data leak

Derek Atkins <derek@ihtfp.com> Wed, 04 November 2015 14:31 UTC

Return-Path: <derek@ihtfp.com>
X-Original-To: openpgp@ietfa.amsl.com
Delivered-To: openpgp@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 4775C1B3083 for <openpgp@ietfa.amsl.com>; Wed, 4 Nov 2015 06:31:58 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2
X-Spam-Level:
X-Spam-Status: No, score=-2 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1] autolearn=ham
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 tTfC6gy5eJc1 for <openpgp@ietfa.amsl.com>; Wed, 4 Nov 2015 06:31:56 -0800 (PST)
Received: from mail2.ihtfp.org (mail2.ihtfp.org [IPv6:2001:4830:143:1::3a11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id EB0861B3084 for <openpgp@ietf.org>; Wed, 4 Nov 2015 06:31:55 -0800 (PST)
Received: from localhost (localhost [127.0.0.1]) by mail2.ihtfp.org (Postfix) with ESMTP id 27E13E2038; Wed, 4 Nov 2015 09:31:53 -0500 (EST)
Received: from mail2.ihtfp.org ([127.0.0.1]) by localhost (mail2.ihtfp.org [127.0.0.1]) (amavisd-maia, port 10024) with ESMTP id 04267-06; Wed, 4 Nov 2015 09:31:50 -0500 (EST)
Received: from securerf.ihtfp.org (unknown [IPv6:fe80::ea2a:eaff:fe7d:235]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mocana.ihtfp.org", Issuer "IHTFP Consulting Certification Authority" (verified OK)) by mail2.ihtfp.org (Postfix) with ESMTPS id 1518CE2035; Wed, 4 Nov 2015 09:31:50 -0500 (EST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ihtfp.com; s=default; t=1446647510; bh=N5Eb+pY8+47uviBjUOv+jSUJhTRTOW3oTovjw8VxiBo=; h=From:To:Cc:Subject:References:Date:In-Reply-To; b=GqsIJIp4vqb/fu0+KkT9L26LsJB5LJ55xnmeBxTbUQuHZBBiIP0gk24Bs6Q+DzhoF vW9DTD0PVRokQztD7bNJvjdzknVz3zB3JjtqvwtMoL0GIoI/DlDoX7ccx+P9L3YT8z JIyuFo5WHKZVDq02+t46oaQuV2H+KMrVhfMDfmlk=
Received: (from warlord@localhost) by securerf.ihtfp.org (8.14.8/8.14.8/Submit) id tA4EVnEY016400; Wed, 4 Nov 2015 09:31:49 -0500
From: Derek Atkins <derek@ihtfp.com>
To: "Neal H. Walfield" <neal@walfield.org>
References: <87io5j764u.wl-neal@walfield.org> <sjm7flz9muf.fsf@securerf.ihtfp.org> <87h9l36tf1.wl-neal@walfield.org>
Date: Wed, 04 Nov 2015 09:31:49 -0500
In-Reply-To: <87h9l36tf1.wl-neal@walfield.org> (Neal H. Walfield's message of "Tue, 03 Nov 2015 15:37:06 +0100")
Message-ID: <sjmpozp96p6.fsf@securerf.ihtfp.org>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux)
MIME-Version: 1.0
Content-Type: text/plain
X-Virus-Scanned: Maia Mailguard 1.0.2a
Archived-At: <http://mailarchive.ietf.org/arch/msg/openpgp/GnK3OkQ4r30YQ1ppODSR-TUvy0s>
Cc: IETF OpenPGP <openpgp@ietf.org>
Subject: Re: [openpgp] Reducing the meta-data leak
X-BeenThere: openpgp@ietf.org
X-Mailman-Version: 2.1.15
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: Wed, 04 Nov 2015 14:31:58 -0000

"Neal H. Walfield" <neal@walfield.org> writes:

> Bryan Ford proposed getting rid of all unencrypted meta-data.  In
> particular, he wanted to get rid of the recipients / number of
> recipients.

I'm not at all sure how you would remove the number of recipients; you
still need N encrypted session key packets.  Therefore anyone reading
the message can count the ESKs.

> There are some practical difficulties with this approach,
> which I mentioned above.
>
> My proposal is a blue sky idea to avoid having to try to decrypt a
> message with every secret key while (hopefully) making it more
> difficult to get at the list of recipients.

Is it really worth the overhead?

> Neal

-derek
-- 
       Derek Atkins                 617-623-3745
       derek@ihtfp.com             www.ihtfp.com
       Computer and Internet Security Consultant

v2.23.0 | Report a Bug | By Email