From owner-freebsd-net@FreeBSD.ORG Sat Oct 2 21:15:49 2010 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0F3531065670 for ; Sat, 2 Oct 2010 21:15:49 +0000 (UTC) (envelope-from andre@freebsd.org) Received: from c00l3r.networx.ch (c00l3r.networx.ch [62.48.2.2]) by mx1.freebsd.org (Postfix) with ESMTP id 9F89E8FC0C for ; Sat, 2 Oct 2010 21:15:48 +0000 (UTC) Received: (qmail 47362 invoked from network); 2 Oct 2010 21:07:21 -0000 Received: from localhost (HELO [127.0.0.1]) ([127.0.0.1]) (envelope-sender ) by c00l3r.networx.ch (qmail-ldap-1.03) with SMTP for ; 2 Oct 2010 21:07:21 -0000 Message-ID: <4CA7A103.3050000@freebsd.org> Date: Sat, 02 Oct 2010 23:15:47 +0200 From: Andre Oppermann User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.9) Gecko/20100825 Thunderbird/3.1.3 MIME-Version: 1.0 To: Jordi Espasa Clofent References: <4CA6FF9A.9090502@minibofh.org> In-Reply-To: <4CA6FF9A.9090502@minibofh.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Cc: freebsd-net@freebsd.org Subject: Re: TCP X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 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, 02 Oct 2010 21:15:49 -0000 On 02.10.2010 11:47, Jordi Espasa Clofent wrote: > Hi all, > > I've read this interesting article: > http://www.packetstan.com/2010/09/openbsd-timestamps.html > > The question is simple > > żIs there some way in FreeBSD to randomize the TCP timestamps as OpenBSD does by default? I guess > some sysctl statement should do it, but I don't know. The timestamps on FreeBSD for passive open are randomized as long as you use SYN cookies (enabled by default). For passive open they are not (yet) randomized. -- Andre