From Hannes.Tschofenig@gmx.net Thu Mar 31 12:34:17 2011 Return-Path: X-Original-To: earlywarning@core3.amsl.com Delivered-To: earlywarning@core3.amsl.com Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id D4A913A6BA1 for ; Thu, 31 Mar 2011 12:34:17 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -102.42 X-Spam-Level: X-Spam-Status: No, score=-102.42 tagged_above=-999 required=5 tests=[AWL=0.179, 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 1IYdR2V6QQT9 for ; Thu, 31 Mar 2011 12:34:16 -0700 (PDT) Received: from mailout-de.gmx.net (mailout-de.gmx.net [213.165.64.22]) by core3.amsl.com (Postfix) with SMTP id 755763A6B94 for ; Thu, 31 Mar 2011 12:34:15 -0700 (PDT) Received: (qmail invoked by alias); 31 Mar 2011 19:35:52 -0000 Received: from dhcp-924f.meeting.ietf.org (EHLO dhcp-924f.meeting.ietf.org) [130.129.10.79] by mail.gmx.net (mp008) with SMTP; 31 Mar 2011 21:35:52 +0200 X-Authenticated: #29516787 X-Provags-ID: V01U2FsdGVkX1/MJAcaVzbMFGLbSr4s1jhvkTpsncupNE4t0uldu0 5lHpbwpXMOg6Cu From: Hannes Tschofenig Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Date: Thu, 31 Mar 2011 21:35:48 +0200 Message-Id: To: earlywarning@ietf.org Mime-Version: 1.0 (Apple Message framework v1084) X-Mailer: Apple Mail (2.1084) X-Y-GMX-Trusted: 0 Cc: Hannes Tschofenig Subject: [Atoca] Remarks on the security discussion today X-BeenThere: earlywarning@ietf.org X-Mailman-Version: 2.1.9 Precedence: list List-Id: "Discussion list for the IETF Authority-to-Citizen Alert \(atoca\) working group." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 31 Mar 2011 19:34:18 -0000 Hi all,=20 in the discussions today a few interesting remarks were raised. I wanted = to share them with you. Richard, Martin and Cullen listed two aspects = that need to be described in the requirements/architecture document, = namely=20 (1) How does the recipient/receiver learn which author/originator to = trust? In this case Richard distinguished two scenarios: a) Tsunami warning Here the warning may be provided to the recipient/receiver by some local = entity. How does the author/originator know when it receives an alert = that can indeed be trusted? It could be sent by anyone. It is not very = likely that the author of the message is known. For this specific case Richard suggested to build on the work in = draft-rosen-ecrit-lost-early-warning-01.txt. The basic idea is that the = receiver uses LoST to discovers organizations issuing alerts for = specific geographical regions. When an alert is received then the author = and/or originator fields are checked against the info previously = obtained via LoST.=20 b) School closed warning Here, the recipient will have a prior relationship with the author (the = school). A prior "registration" step is likely going to be required.=20 (2) Transitive Trust vs. End-to-End Security In order to ensure that the comparison between the identity information = can be processed by the recipient/receiver there is a need for = cryptographic assurance. During the meeting we had discussed the = possibility to use transitive trust (I know my service provider and I = assume that he will only accept and forward alerts it got from other = trusted sources) and end-to-end security.=20 In the area of end-to-end security it was noticed that the deployment = reality of SIP (and XMPP) with regard to e2e security is rather weak. = Security at the alert level was seen as OK but XMLDSIG was not = acceptable.=20 I hope my writeup makes sense (even though I am tired already).=20 Ciao Hannes From artbotterell@gmail.com Thu Mar 31 12:42:51 2011 Return-Path: X-Original-To: earlywarning@core3.amsl.com Delivered-To: earlywarning@core3.amsl.com Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id D97E528C0E1 for ; Thu, 31 Mar 2011 12:42:51 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -3.599 X-Spam-Level: X-Spam-Status: No, score=-3.599 tagged_above=-999 required=5 tests=[BAYES_00=-2.599, RCVD_IN_DNSWL_LOW=-1] 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 FJI6-ltUZs+j for ; Thu, 31 Mar 2011 12:42:51 -0700 (PDT) Received: from mail-iy0-f172.google.com (mail-iy0-f172.google.com [209.85.210.172]) by core3.amsl.com (Postfix) with ESMTP id 1BFD428C0D8 for ; Thu, 31 Mar 2011 12:42:51 -0700 (PDT) Received: by iye19 with SMTP id 19so3150931iye.31 for ; Thu, 31 Mar 2011 12:44:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:content-type:mime-version:subject:from :in-reply-to:date:content-transfer-encoding:message-id:references:to :x-mailer; bh=DRJ5LPHfvMMWDe20BrIbSoI7/VS3Y+r3fntYYhJ5sXg=; b=m09ddFU1aDX74dpQhdy9V/+vUhuAIehOt8ypHYQ/aRDF6TN/E7tkWMIhLvH1ShN6/3 fLV7waA2CP68OcTusKGXPvkpk4TICuSJoEoGgOXdUmeR5tlD+nYD/k3dxh+LNgJFCosX 85/mmHcjPEF6oYkHKCobumJPF/jLBNnJX7ag4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:content-type:mime-version:subject:from:in-reply-to:date :content-transfer-encoding:message-id:references:to:x-mailer; b=ch1ddnkTe30NlpRLvNJWjmnYfS/LRtMRvIwMJuYNzIiv/xFOvoYiAFG719iktGKnaE L5zb4+Jvmm6NhfqdVa1D6ozCwDgBN9ehFqnxMSPV7EAbefwbZgacCKatr/rlOSsAEfyS JXyV5v2c0zkh34xGE6bDlDgbfSItGr4l7t+2g= Received: by 10.43.54.71 with SMTP id vt7mr3848144icb.225.1301600670869; Thu, 31 Mar 2011 12:44:30 -0700 (PDT) Received: from [192.168.1.14] (99-182-125-96.lightspeed.frokca.sbcglobal.net [99.182.125.96]) by mx.google.com with ESMTPS id 8sm927333iba.38.2011.03.31.12.44.29 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 31 Mar 2011 12:44:30 -0700 (PDT) Sender: Art Botterell Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Apple Message framework v1084) From: Art Botterell In-Reply-To: Date: Thu, 31 Mar 2011 12:44:28 -0700 Content-Transfer-Encoding: quoted-printable Message-Id: References: To: earlywarning@ietf.org X-Mailer: Apple Mail (2.1084) Subject: Re: [Atoca] Remarks on the security discussion today X-BeenThere: earlywarning@ietf.org X-Mailman-Version: 2.1.9 Precedence: list List-Id: "Discussion list for the IETF Authority-to-Citizen Alert \(atoca\) working group." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 31 Mar 2011 19:42:51 -0000 On Mar 31, 2011, at 12:35 PM, Hannes Tschofenig wrote: > In the area of end-to-end security it was noticed that the deployment = reality of SIP (and XMPP) with regard to e2e security is rather weak. = Security at the alert level was seen as OK but XMLDSIG was not = acceptable.=20 Hannes, could please you say a bit more about that? In particular, what = was meant by "OK" and "not acceptable"? On a related note, I'd suggest that digital signatures may sometimes be = useful even in transitive trust regimes in order to make the = certification of an alert, wherever it occurred, provably persistent = over time for auditing and forensic purposes. - Art