From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alejandro Riveira =?UTF-8?B?RmVybsOhbmRleg==?= Subject: Re: [PATCH] drivers/net: remove network drivers' last few uses of IRQF_SAMPLE_RANDOM Date: Mon, 26 May 2008 15:43:26 +0200 Message-ID: <20080526154326.1fe44214@Varda> References: <482C7E53.3050300@hp.com> <482C8184.2030906@garzik.org> <482C8550.5000909@intel.com> <482C8D4D.3040702@garzik.org> <20080516132107.GA11304@csclub.uwaterloo.ca> <20080516161029.44ded734@core> <20080516173610.GA27126@csclub.uwaterloo.ca> <20080516191125.46f59ad6@core> <1211728189.5913.71.camel@andromache> <20080525232712.GF5970@mit.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Glen Turner , Chris Peterson , Alan Cox , Lennart Sorensen , Jeff Garzik , "Kok, Auke" , Rick Jones , "Brandeburg, Jesse" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: Theodore Tso Return-path: Received: from ug-out-1314.google.com ([66.249.92.168]:5675 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756267AbYEZNnh convert rfc822-to-8bit (ORCPT ); Mon, 26 May 2008 09:43:37 -0400 Received: by ug-out-1314.google.com with SMTP id h2so414260ugf.16 for ; Mon, 26 May 2008 06:43:35 -0700 (PDT) In-Reply-To: <20080525232712.GF5970@mit.edu> Sender: netdev-owner@vger.kernel.org List-ID: El Sun, 25 May 2008 19:27:12 -0400 Theodore Tso escribi=C3=B3: > On Mon, May 26, 2008 at 12:39:49AM +0930, Glen Turner wrote: > >=20 > > For example, /dev/random has run out. So the output of /dev/urandom > > is now determined by previous values of /dev/random. I then send i= n > > a stack of network packets at regular intervals. So the output of > > /dev/urandom is now greatly determined by those packets. My search > > space for the resulting key is small since /dev/urandom appears to > > be random, but in fact is periodic. >=20 > That's not how it works. Basically, as long as there is *some* > entropy in the system, even from the /var/lib/random-seed, or from > keyboard interrupts, or from mouse interrupts, which is unknown to th= e > attacker, in the worse case /dev/urandom will be no worse than a > cryptographic random number generator. >=20 [ ... ]=20 =20 Just a shot in the dark... would hw sensors (raw data) chips be a good= source of entropy for /dev/random ??=20 > - Ted > -- > To unsubscribe from this list: send the line "unsubscribe linux-kerne= l" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/