From owner-freebsd-current@FreeBSD.ORG Sun Nov 9 12:59:57 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3209D16A4CE; Sun, 9 Nov 2003 12:59:57 -0800 (PST) Received: from westhost42.westhost.net (westhost42.westhost.net [216.71.84.238]) by mx1.FreeBSD.org (Postfix) with ESMTP id 21CE143FBD; Sun, 9 Nov 2003 12:59:56 -0800 (PST) (envelope-from mini@freebsd.org) Received: from [10.0.1.20] (12-228-13-123.client.attbi.com [12.228.13.123]) by westhost42.westhost.net (8.11.6/8.11.6) with ESMTP id hA9Kxs727738; Sun, 9 Nov 2003 14:59:54 -0600 In-Reply-To: <3FAE68FB.64D262FF@pipeline.ch> References: <3FAE68FB.64D262FF@pipeline.ch> Mime-Version: 1.0 (Apple Message framework v606) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: Content-Transfer-Encoding: 7bit From: Jonathan Mini Date: Sun, 9 Nov 2003 12:59:57 -0800 To: Andre Oppermann X-Mailer: Apple Mail (2.606) cc: mb@imp.ch cc: freebsd-current@freebsd.org cc: ume@freebsd.org cc: sam@errno.com cc: freebsd-net@freebsd.org Subject: Re: tcp hostcache and ip fastforward for review X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 09 Nov 2003 20:59:57 -0000 On Nov 9, 2003, at 8:19 AM, Andre Oppermann wrote: > - DoS attack 2: make MSS very low on local side of connection > and send maaaany small packet to remote host. For every packet > (eg. 2 bytes payload) a sowakeup is done to the listening > process. Consumes a lot of CPU there. > This sounds as if it might be worthwhile to add a delay to the TF_NODELAY case for receive processing as well. -- Jonathan Mini mini@freebsd.org http://www.freebsd.org