From owner-freebsd-security@FreeBSD.ORG Fri Sep 14 19:37:33 2012 Return-Path: Delivered-To: freebsd-security@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id AE9E8106566B; Fri, 14 Sep 2012 19:37:33 +0000 (UTC) (envelope-from des@des.no) Received: from smtp.des.no (smtp.des.no [194.63.250.102]) by mx1.freebsd.org (Postfix) with ESMTP id 662EE8FC08; Fri, 14 Sep 2012 19:37:33 +0000 (UTC) Received: from ds4.des.no (smtp.des.no [194.63.250.102]) by smtp.des.no (Postfix) with ESMTP id 6D2B3619D; Fri, 14 Sep 2012 21:37:32 +0200 (CEST) Received: by ds4.des.no (Postfix, from userid 1001) id 3B4718EC9; Fri, 14 Sep 2012 21:37:32 +0200 (CEST) From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= To: Pawel Jakub Dawidek References: <86sjao7q8c.fsf@ds4.des.no> <20120911205302.27484fd6@gumby.homeunix.com> <20120911200925.GA88456@dragon.NUXI.org> <504FA76A.5000209@delphij.net> <20120911211730.GB89188@dragon.NUXI.org> <504FAB87.3020701@delphij.net> <20120911215212.GA89515@dragon.NUXI.org> <504FBD15.8040907@delphij.net> <20120911224855.GE14077@x96.org> <504FC2BD.6070402@delphij.net> <20120914153030.GA2146@garage.freebsd.pl> Date: Fri, 14 Sep 2012 21:37:31 +0200 In-Reply-To: <20120914153030.GA2146@garage.freebsd.pl> (Pawel Jakub Dawidek's message of "Fri, 14 Sep 2012 17:30:30 +0200") Message-ID: <86vcfge6pw.fsf@ds4.des.no> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.4 (berkeley-unix) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: Arthur Mesh , Doug Barton , freebsd-rc@freebsd.org, freebsd-security@freebsd.org, RW , d@delphij.net Subject: Re: svn commit: r239569 - head/etc/rc.d X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Sep 2012 19:37:33 -0000 Pawel Jakub Dawidek writes: > Also, compression can definiately increase entropy per byte, but IMHO it > can also lose some entropy overall. With lossless compression you don't > lose data, but I don't believe you can say that you don't lose entropy. By definition (both the definition of entropy in this context and the definition of lossless data compression), the amount of entropy in the output is exactly the same as in the input. If the output is actually smaller than the input (which is not necessarily the case, but is safe to assume when the input is ascii text), then clearly the amount of entropy per byte has increased. DES --=20 Dag-Erling Sm=C3=B8rgrav - des@des.no