From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268338AbUHXVWe (ORCPT ); Tue, 24 Aug 2004 17:22:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268332AbUHXVWe (ORCPT ); Tue, 24 Aug 2004 17:22:34 -0400 Received: from waste.org ([209.173.204.2]:39842 "EHLO waste.org") by vger.kernel.org with ESMTP id S268339AbUHXVW2 (ORCPT ); Tue, 24 Aug 2004 17:22:28 -0400 Date: Tue, 24 Aug 2004 16:22:08 -0500 From: Matt Mackall To: "Theodore Ts'o" Cc: linux-kernel@vger.kernel.org, akpm@osdl.org Subject: Re: [PATCH] [3/4] /dev/random: Use separate entropy store for /dev/urandom Message-ID: <20040824212208.GH5414@waste.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.3.28i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 20, 2004 at 12:57:20AM -0400, Theodore Ts'o wrote: > > This patch adds a separate pool for use with /dev/urandom. This > prevents a /dev/urandom read from being able to completely drain the > entropy in the /dev/random pool, and also makes it much more difficult > for an attacker to carry out a state extension attack. My version of this went a step further. We want to at all times ensure that there's enough data to do a full catastrophic reseed in the blocking pool, so we have to assure we're never drawing below that point when doing reads for urandom. -- Mathematics is the supreme nostalgia of our time.