From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20224 invoked by alias); 3 Apr 2008 19:18:57 -0000 Received: (qmail 20208 invoked by uid 22791); 3 Apr 2008 19:18:56 -0000 X-Spam-Check-By: sourceware.org Received: from main.gmane.org (HELO ciao.gmane.org) (80.91.229.2) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 03 Apr 2008 19:18:31 +0000 Received: from list by ciao.gmane.org with local (Exim 4.43) id 1JhUx5-0005uf-3B for ecos-discuss@sources.redhat.com; Thu, 03 Apr 2008 19:18:23 +0000 Received: from 64.251.14.41 ([64.251.14.41]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 03 Apr 2008 19:18:23 +0000 Received: from grante by 64.251.14.41 with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 03 Apr 2008 19:18:23 +0000 To: ecos-discuss@sources.redhat.com From: Grant Edwards Date: Thu, 03 Apr 2008 19:29:00 -0000 Message-ID: References: User-Agent: slrn/0.9.8.1pl1 (Linux) X-IsSubscribed: yes Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Subject: [ECOS] Re: Entropy gathering? X-SW-Source: 2008-04/txt/msg00054.txt.bz2 On 2008-04-03, Grant Edwards wrote: > The BSD stacks appear to use an aRC4 keystream for "random" > data. The stream uses a constant seed and then mixes in the > system clock value. It could be worse, but it's not great > either. Upon reading the above statement, I think I should clarify that the "system time" that's mixed in is the HAL's hardware counter value and not the system tick count time. The hardware counter is changing much faster (a good thing), but it provides relatively few bits (on my targets, it ranges from 14-18). -- Grant Edwards grante Yow! My mind is making at ashtrays in Dayton ... visi.com -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss