Re: [Suit] suit-firmware-encryption-00

Russ Housley <housley@vigilsec.com> Mon, 31 May 2021 16:56 UTC

Return-Path: <housley@vigilsec.com>
X-Original-To: suit@ietfa.amsl.com
Delivered-To: suit@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 105D93A1E99 for <suit@ietfa.amsl.com>; Mon, 31 May 2021 09:56:17 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.897
X-Spam-Level:
X-Spam-Status: No, score=-1.897 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_NONE=0.001, URIBL_BLOCKED=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 UUfmt61kdItB for <suit@ietfa.amsl.com>; Mon, 31 May 2021 09:56:12 -0700 (PDT)
Received: from mail.smeinc.net (mail.smeinc.net [209.135.209.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E2B3C3A1E96 for <suit@ietf.org>; Mon, 31 May 2021 09:56:11 -0700 (PDT)
Received: from localhost (localhost [127.0.0.1]) by mail.smeinc.net (Postfix) with ESMTP id BC59A300BE6 for <suit@ietf.org>; Mon, 31 May 2021 12:56:10 -0400 (EDT)
X-Virus-Scanned: amavisd-new at mail.smeinc.net
Received: from mail.smeinc.net ([127.0.0.1]) by localhost (mail.smeinc.net [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id sNSgtJeZCFxI for <suit@ietf.org>; Mon, 31 May 2021 12:56:04 -0400 (EDT)
Received: from a860b60074bd.fios-router.home (pool-141-156-161-153.washdc.fios.verizon.net [141.156.161.153]) by mail.smeinc.net (Postfix) with ESMTPSA id AA833300A48; Mon, 31 May 2021 12:56:04 -0400 (EDT)
Content-Type: text/plain; charset="us-ascii"
Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.20\))
From: Russ Housley <housley@vigilsec.com>
In-Reply-To: <132601d7563d$7097f680$51c7e380$@reliableenergyanalytics.com>
Date: Mon, 31 May 2021 12:56:04 -0400
Cc: Michael Richardson <mcr+ietf@sandelman.ca>, Hannes Tschofenig <Hannes.Tschofenig@arm.com>, suit@ietf.org
Content-Transfer-Encoding: quoted-printable
Message-Id: <E2D893E5-8462-4F69-88D0-29167B6DB1B3@vigilsec.com>
References: <19586.1622075797@localhost> <DBBPR08MB5915CEC125579D78C108D540FA3F9@DBBPR08MB5915.eurprd08.prod.outlook.com> <F6C86CC2-3AF8-4CC5-BB47-AC6579DAA0C4@vigilsec.com> <13894.1622479289@localhost> <64BDF7A0-4B70-4EB3-A764-2BD6CAA3921A@vigilsec.com> <132601d7563d$7097f680$51c7e380$@reliableenergyanalytics.com>
To: Dick Brooks <dick@reliableenergyanalytics.com>
X-Mailer: Apple Mail (2.3445.104.20)
Archived-At: <https://mailarchive.ietf.org/arch/msg/suit/SuvDmIcJ79jGMU8sU44oCAA9M_A>
Subject: Re: [Suit] suit-firmware-encryption-00
X-BeenThere: suit@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Software Updates for Internet of Things <suit.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/suit>, <mailto:suit-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/suit/>
List-Post: <mailto:suit@ietf.org>
List-Help: <mailto:suit-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/suit>, <mailto:suit-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 31 May 2021 16:56:17 -0000

Dick:

Yes, and there are other use cases that require encryption.

Russ


> On May 31, 2021, at 12:53 PM, Dick Brooks <dick@reliableenergyanalytics.com> wrote:
> 
> " If a trustworthy party in the middle of the distribution path is able to
> detect a problem with cleartext (but signed) firmware, they can report a
> vulnerability and refuse to pass the update along."
> 
> This is precisely the function SCRM vendors are performing today. Encrypting
> a binary object would be an impediment to software supply chain risk
> assessment functions in place today.
> 
> Thanks,
> 
> Dick Brooks
> 
> Never trust software, always verify and report! T
> http://www.reliableenergyanalytics.com
> Email: dick@reliableenergyanalytics.com
> Tel: +1 978-696-1788
> 
> -----Original Message-----
> From: Suit <suit-bounces@ietf.org> On Behalf Of Russ Housley
> Sent: Monday, May 31, 2021 12:49 PM
> To: Michael Richardson <mcr+ietf@sandelman.ca>
> Cc: Hannes Tschofenig <Hannes.Tschofenig@arm.com>; suit@ietf.org
> Subject: Re: [Suit] suit-firmware-encryption-00
> 
> Michael:
> 
>>>> I agree that there are also challenges with certification schemes 
>>>> that prevent developers from seeing the source code (or from 
>>>> publishing the source code). That's yet another issue.
>> 
>>> SUIT is using signature for the authentication and integrity of the 
>>> firmware.  If the signature remains in place, a party in the middle 
>>> of the distribution cannot insert any malware.
>> 
>> The encryption of the firmware keeps third parties from auditing the 
>> software updates to determine if malware has been inserted at the
> "factory"
>> Both white and black hats are currently using binary diff systems to 
>> look at patches.  Black hats use this to develop exploits in the gap 
>> between 9am EST and 9am PST!
>> I am suggesting that this is a "Security Consideration"
> 
> Yes, this is a reasonable thing to add to the Security Considerations.
> 
> If a trustworthy party in the middle of the distribution path is able to
> detect a problem with cleartext (but signed) firmware, they can report a
> vulnerability and refuse to pass the update along.
> 
> Russ
> _______________________________________________
> Suit mailing list
> Suit@ietf.org
> https://www.ietf.org/mailman/listinfo/suit
>