From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754771AbXE2QCX (ORCPT ); Tue, 29 May 2007 12:02:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751859AbXE2QCQ (ORCPT ); Tue, 29 May 2007 12:02:16 -0400 Received: from ns2.suse.de ([195.135.220.15]:37976 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751724AbXE2QCQ (ORCPT ); Tue, 29 May 2007 12:02:16 -0400 To: "M Macnair" Cc: linux-kernel@vger.kernel.org Subject: Re: Seeding /dev/random not working References: From: Andi Kleen Date: 29 May 2007 18:58:59 +0200 In-Reply-To: Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org "M Macnair" writes: > > Many distros ship with an init script that saves and restores the > entropy pool on startup and shutdown. The bit that interests me that > is called on startup is (my comments): > if [ -f $random_seed ]; then > cat $random_seed >/dev/urandom # should seed the pool OA Writing doesn't actually work; to get real accounted entropy for /dev/random you need to use a special ioctl. I ran into this problem some years ago and ended up writing http://www.muc.de/~ak/rndfeed.c -Andi