From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750782AbWGFVkk (ORCPT ); Thu, 6 Jul 2006 17:40:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750787AbWGFVkk (ORCPT ); Thu, 6 Jul 2006 17:40:40 -0400 Received: from mail-in-08.arcor-online.net ([151.189.21.48]:61117 "EHLO mail-in-08.arcor-online.net") by vger.kernel.org with ESMTP id S1750782AbWGFVkj (ORCPT ); Thu, 6 Jul 2006 17:40:39 -0400 From: Bodo Eggert <7eggert@elstempel.de> Subject: Re: Driver for Microsoft USB Fingerprint Reader To: Alan Cox , linux@horizon.com, linux-kernel@vger.kernel.org Reply-To: 7eggert@gmx.de Date: Thu, 06 Jul 2006 23:39:44 +0200 References: <6vtYr-w2-5@gated-at.bofh.it> <6vFQ5-1iV-71@gated-at.bofh.it> User-Agent: KNode/0.7.2 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8Bit X-Troll: Tanz Message-Id: X-be10.7eggert.dyndns.org-MailScanner-Information: See www.mailscanner.info for information X-be10.7eggert.dyndns.org-MailScanner: Found to be clean X-be10.7eggert.dyndns.org-MailScanner-From: 7eggert@elstempel.de Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Alan Cox wrote: > Ar Iau, 2006-07-06 am 00:48 -0400, ysgrifennodd linux@horizon.com: >> As far as I can tell, the only thing you want is AUTHENTICATION - you >> want proof that you are getting a "live" scan taken from a user >> who's present, and not a replay of what was sent last week. > > Read the papers on the subject. If I can get copies of the unencrypted > data I can use those to make fake fingers. Copies like the one on the glass I used in the restaurant ... > A finger print is personal data, arguably sensitive personal data. That > means there are lots of duties to store it securely. That's why every waiter will assiduously clean your glass. won't he? > It is also very > hard to revoke a fingerprint so theft of data is highly problematic as > it will allow me to generate fake fingers. That's the problem: You can't know who is acting responsibly and who isn't. Therefore you can't reuse your fingerprint on different sites. > Theft of encrypted data might > allow replay attacks on one PC. Big deal. ACK. It should be protected by a nonce, too, as long as you depend on encryption. You should also authenticate the reader before prompting for a fingerprint, otherwise the replacement device might store the image to a secondary location. And don't forget to prompt for cleaning the scanner, I have heared rumors about scanners erroneously authenticating the previous user. You should also install a camera preventing an attacker to place his own scanner on top of yours. -- Ich danke GMX dafür, die Verwendung meiner Adressen mittels per SPF verbreiteten Lügen zu sabotieren. http://david.woodhou.se/why-not-spf.html