From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Will Newton" Subject: Re: [PATCH] drivers/net: remove network drivers' last few uses of IRQF_SAMPLE_RANDOM Date: Fri, 16 May 2008 14:59:03 +0100 Message-ID: <87a5b0800805160659j1e8482efjea2fb8167f755e05@mail.gmail.com> References: <20080515142154.0595e475@core> <36D9DB17C6DE9E40B059440DB8D95F52052D71BB@orsmsx418.amr.corp.intel.com> <482C7B18.6060003@garzik.org> <482C7E53.3050300@hp.com> <482C8184.2030906@garzik.org> <482C8550.5000909@intel.com> <482C8D4D.3040702@garzik.org> <20080516132107.GA11304@csclub.uwaterloo.ca> <482D8EE9.10404@garzik.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "Lennart Sorensen" , "Kok, Auke" , "Rick Jones" , "Brandeburg, Jesse" , "Alan Cox" , "Chris Peterson" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: "Jeff Garzik" Return-path: Received: from yw-out-2324.google.com ([74.125.46.28]:14166 "EHLO yw-out-2324.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751309AbYEPN7F (ORCPT ); Fri, 16 May 2008 09:59:05 -0400 Received: by yw-out-2324.google.com with SMTP id 9so514241ywe.1 for ; Fri, 16 May 2008 06:59:04 -0700 (PDT) In-Reply-To: <482D8EE9.10404@garzik.org> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: On Fri, May 16, 2008 at 2:40 PM, Jeff Garzik wrote: > Lennart Sorensen wrote: >> >> On Thu, May 15, 2008 at 03:21:49PM -0400, Jeff Garzik wrote: >>> >>> "no other form of entropy"? See examples in this thread. >> >> So where does one get entropy if not the ethernet adapter on many >> embedded systems? If you have no mouse, no keyboard, no hardware number >> generator, just ethernet ports and a serial console that usually >> receives no input. While ethernet might not be preferable if you have >> something else, sometimes you really don't have anything else. > > Already answered in this thread... EGD illustrates how many sources of > entropy remain, even in the example you just gave. > > Further, you do not want to rely on entropy from a source that declines just > as network traffic increases. I don't know egd that well, but from a cursory look it gets data from such things as w or last (wtmp) which is static on most embedded boxes. It also uses netstat and snmp - surely this is at least as easy to manipulate as interrupt timings? I'm not a cryptographer by any means but it looks as if it works by magic. Last changed 2002, written in perl. No, I don't think I'll be shipping this on any systems any time soon.