From owner-freebsd-net@FreeBSD.ORG Sat Mar 12 20:44:35 2005 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8B97216A4CE for ; Sat, 12 Mar 2005 20:44:35 +0000 (GMT) Received: from relay01.pair.com (relay01.pair.com [209.68.5.15]) by mx1.FreeBSD.org (Postfix) with SMTP id BE39943D49 for ; Sat, 12 Mar 2005 20:44:34 +0000 (GMT) (envelope-from silby@silby.com) Received: (qmail 54475 invoked from network); 12 Mar 2005 20:44:33 -0000 Received: from unknown (HELO localhost) (unknown) by unknown with SMTP; 12 Mar 2005 20:44:33 -0000 X-pair-Authenticated: 209.68.2.70 Date: Sat, 12 Mar 2005 14:44:32 -0600 (CST) From: Mike Silbersack To: Anthony Atkielski In-Reply-To: <771770969.20050311034646@wanadoo.fr> Message-ID: <20050312144141.P15599@odysseus.silby.com> References: <771770969.20050311034646@wanadoo.fr> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed cc: freebsd-net@freebsd.org Subject: Re: Clock slew vulnerability in FreeBSD? X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 12 Mar 2005 20:44:35 -0000 On Fri, 11 Mar 2005, Anthony Atkielski wrote: > > How vulnerable is FreeBSD to the recently announced technique for > individually identifying computers by the clock slew apparent in TCP > packets? If it is vulnerable to this, will there be any plans to > address the vulnerability? > > -- > Anthony I finally read the paper (instead of just reading the abstract), and I must say that it's a lot more interesting than I would have expected it to be. Defeating this technique would be relatively easy to do, but there are a lot of other much easier ways to identify FreeBSD machines right now. Once those are fixed, then this can be worried about. (For example, we send the same TCP timestamps to all hosts right now; no need to measure clock skew!) Mike "Silby" Silbersack