Re: [secdir] SecDir review of draft-loreto-http-bidirectional-05

Peter Saint-Andre <stpeter@stpeter.im> Mon, 03 January 2011 18:59 UTC

Return-Path: <stpeter@stpeter.im>
X-Original-To: secdir@core3.amsl.com
Delivered-To: secdir@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id EF6823A6AB1; Mon, 3 Jan 2011 10:59:50 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -102.468
X-Spam-Level:
X-Spam-Status: No, score=-102.468 tagged_above=-999 required=5 tests=[AWL=0.131, BAYES_00=-2.599, USER_IN_WHITELIST=-100]
Received: from mail.ietf.org ([64.170.98.32]) by localhost (core3.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id icurMfovEPTh; Mon, 3 Jan 2011 10:59:49 -0800 (PST)
Received: from stpeter.im (stpeter.im [207.210.219.233]) by core3.amsl.com (Postfix) with ESMTP id 8C0733A6AB0; Mon, 3 Jan 2011 10:59:49 -0800 (PST)
Received: from leavealone.cisco.com (72-163-0-129.cisco.com [72.163.0.129]) (Authenticated sender: stpeter) by stpeter.im (Postfix) with ESMTPSA id 382AA4009B; Mon, 3 Jan 2011 12:16:07 -0700 (MST)
Message-ID: <4D221D21.40107@stpeter.im>
Date: Mon, 03 Jan 2011 12:01:53 -0700
From: Peter Saint-Andre <stpeter@stpeter.im>
User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.2.13) Gecko/20101207 Thunderbird/3.1.7
MIME-Version: 1.0
To: "Laganier, Julien" <julienl@qualcomm.com>
References: <BF345F63074F8040B58C00A186FCA57F29F6FBFE5D@NALASEXMB04.na.qualcomm.com>
In-Reply-To: <BF345F63074F8040B58C00A186FCA57F29F6FBFE5D@NALASEXMB04.na.qualcomm.com>
X-Enigmail-Version: 1.1.1
OpenPGP: url=http://www.saint-andre.com/me/stpeter.asc
Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha1; boundary="------------ms050408000207060805080501"
X-Mailman-Approved-At: Thu, 06 Jan 2011 09:46:04 -0800
Cc: "draft-loreto-http-bidirectional.all@tools.ietf.org" <draft-loreto-http-bidirectional.all@tools.ietf.org>, "iesg@ietf.org" <iesg@ietf.org>, "secdir@ietf.org" <secdir@ietf.org>
Subject: Re: [secdir] SecDir review of draft-loreto-http-bidirectional-05
X-BeenThere: secdir@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: Security Area Directorate <secdir.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/secdir>, <mailto:secdir-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/secdir>
List-Post: <mailto:secdir@ietf.org>
List-Help: <mailto:secdir-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/secdir>, <mailto:secdir-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 03 Jan 2011 18:59:51 -0000

Thanks for your review, and our apologies for the delayed reply.

On 12/16/10 9:38 AM, Laganier, Julien wrote:
> I have reviewed this document as part of the security directorate's
> ongoing effort to review all IETF documents being processed by the
> IESG.  These comments were written primarily for the benefit of the
> security area directors.  Document editors and WG chairs should treat
> these comments just like any other last call comments.
> 
> The document describes "Known issues and best practices for the Use
> of Long Polling and                    Streaming in Bidirectional
> HTTP", and it has the following abstract:
> 
> There is widespread interest in using the Hypertext Transfer
> Protocol (HTTP) to enable asynchronous or server-initiated
> communication from a server to a client as well as from a client to a
> server.  This document describes the known issues and the best
> practices related to the use of HTTP, as it exists today, to enable
> such "bidirectional HTTP".  The two existing mechanisms, called "HTTP
> long polling" and "HTTP streaming" are described.
> 
> The document is very clear and articulate and I have not found any
> security issues that were not covered appropriately in the Security
> Considerations sections.
> 
> I have two concerns regarding the use of "should", "must" etc.:
> 
> 1. I have found at least one occurrence where a recommendation is
> made using lower cases "recommended" and "should". Should upper cases
> be used instead?

Currently this document does not reference RFC 2119 or use capitalized
keywords. Instead of adding such a reference, I suggest changing that
text to:

   Several experiments have shown success with timeouts as high as 120
   seconds, but generally 30 seconds is a safer value.  Therefore
   vendors of network equipment wishing to be compatible with the HTTP
   long polling mechanism are advised to implement a timeout
   substantially greater than 30 seconds (where "substantially" means
   several times more than the medium network transit time).

> 2. Similarly, parts of the text describes node behavior using lower
> cases "should" and "must". This makes it hard for the reader to
> differentiate between behavior specified in another standard document
> from behavior that can be reasonably expected from a deployed
> implementation. I would suggest that upper case requirements key
> words ("SHOULD", "MUST") be used if the behavior thereby enounced is
> specified within another RFC documents, and that document be cited
> next to the statement.

The sentences you mention indeed simply cite other RFCs. Because the
actual normative text is contained in the referenced RFCs, I suggest
that we remove the lowercase "should" and "must" words from this I-D.

> Nits:
> 
> s/DOS attacks\.[RFC4732]/Denial-of-Service (DoS) attacks [RFC4732]/

Fixed.

Peter

-- 
Peter Saint-Andre
https://stpeter.im/