From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1Las4J-0001vo-Lw for mharc-grub-devel@gnu.org; Sat, 21 Feb 2009 08:38:59 -0500 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Las4I-0001vj-5Q for grub-devel@gnu.org; Sat, 21 Feb 2009 08:38:58 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Las4G-0001vR-Kg for grub-devel@gnu.org; Sat, 21 Feb 2009 08:38:57 -0500 Received: from [199.232.76.173] (port=43392 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Las4G-0001vM-Bu for grub-devel@gnu.org; Sat, 21 Feb 2009 08:38:56 -0500 Received: from aybabtu.com ([69.60.117.155]:36540) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1Las4F-000591-PR for grub-devel@gnu.org; Sat, 21 Feb 2009 08:38:56 -0500 Received: from [192.168.10.10] (helo=thorin) by aybabtu.com with esmtp (Exim 4.69) (envelope-from ) id 1Larxj-00074g-9L for grub-devel@gnu.org; Sat, 21 Feb 2009 14:32:11 +0100 Received: from rmh by thorin with local (Exim 4.69) (envelope-from ) id 1Las4C-0004Fr-Kp for grub-devel@gnu.org; Sat, 21 Feb 2009 14:38:52 +0100 Date: Sat, 21 Feb 2009 14:38:52 +0100 From: Robert Millan To: The development of GRUB 2 Message-ID: <20090221133852.GI16068@thorin> References: <499C7809.6030203@student.ethz.ch> <499D7526.70907@gmail.com> <20090219073836.2d532392@gibibit.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090219073836.2d532392@gibibit.com> Organization: free as in freedom X-Message-Flag: Worried about Outlook viruses? Switch to Thunderbird! www.mozilla.com/thunderbird X-Debbugs-No-Ack: true User-Agent: Mutt/1.5.18 (2008-05-17) X-detected-operating-system: by monty-python.gnu.org: Genre and OS details not recognized. Subject: Re: A _good_ and valid use for TPM X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 21 Feb 2009 13:38:58 -0000 On Thu, Feb 19, 2009 at 07:38:36AM -0800, Colin D Bennett wrote: > > While TPM may open a door for corporations to prevent machine owners > from having control over their machines, in this instance I do not see > another way to solve Alex's problem. There's an easy way out of this. Simply verify data integrity from the flash chip, and make sure nobody can write to the flash chip. You can archieve the first by e.g. installing coreboot/GRUB there and add some crypto support to it. You can archieve the second by cutting the WE wire, or by dumping lots of concrete over your board. Yes, this is a gazillon times more secure than a TPM. TPMs are vulnerable to reverse engineering. > The evil part of TPM seems to be when a person buys a computer but the > computer is locked down with a key not provided to the buyer. Precisely. If it came with a key that is known to the buyer (e.g. printed on paper), or with an override mechanism that is only accessible to its legitimate buyer, there would be no problem with it. But AFAICT there are no TPMs that do this. It probably even violates the spec. -- Robert Millan The DRM opt-in fallacy: "Your data belongs to us. We will decide when (and how) you may access your data; but nobody's threatening your freedom: we still allow you to remove your data and not access it at all."