From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1Las8o-0004ki-Qc for mharc-grub-devel@gnu.org; Sat, 21 Feb 2009 08:43:38 -0500 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Las8k-0004jL-Ad for grub-devel@gnu.org; Sat, 21 Feb 2009 08:43:34 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Las8i-0004j9-5m for grub-devel@gnu.org; Sat, 21 Feb 2009 08:43:33 -0500 Received: from [199.232.76.173] (port=56031 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Las8h-0004j6-Fn for grub-devel@gnu.org; Sat, 21 Feb 2009 08:43:31 -0500 Received: from fg-out-1718.google.com ([72.14.220.157]:11217) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1Las8h-0006D7-0K for grub-devel@gnu.org; Sat, 21 Feb 2009 08:43:31 -0500 Received: by fg-out-1718.google.com with SMTP id l27so1650487fgb.30 for ; Sat, 21 Feb 2009 05:43:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from :user-agent:mime-version:to:subject:references:in-reply-to :content-type:content-transfer-encoding; bh=sbkv0eHH+3v/F7K+Exq79Rydjl20EexL/Xbz8x/jIt0=; b=qqk52/hvq3VMjbXmmwgRhbxHw45iE1WrVi/yaC9jWZhNBkjhV1Pbxla8mEWmnBiU6/ MzDkDih+uPgwhJsNh8hA7VXUjzeUihaRCUvlujMHF4GrhBEzIaahgB+U6J8SvhukS1ss XN8xL4+OG+cgbjqK63p6Ov6Kz3ERsk5h7W8J4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:content-type:content-transfer-encoding; b=pyCj/b4ymjV8m51GGEnL/DnTc/tkKPRCfkH4zX9Iof6I4ipram9d4Y/LWFvfq1Wpgw NXmmSmNE7F02vzEPe9+LQ3Xzlic0pqBBValAkEqXg6UeZ1TiXAFJxJ5Cv6m7/EYfS3v6 5JvkXUG0rNM1864zUoAQ3q+CiImyJNcrhzzsQ= Received: by 10.86.92.4 with SMTP id p4mr1695193fgb.36.1235223810223; Sat, 21 Feb 2009 05:43:30 -0800 (PST) Received: from ?192.168.1.25? (166-90.62-81.cust.bluewin.ch [81.62.90.166]) by mx.google.com with ESMTPS id e20sm9987733fga.56.2009.02.21.05.43.29 (version=SSLv3 cipher=RC4-MD5); Sat, 21 Feb 2009 05:43:29 -0800 (PST) Message-ID: <49A00501.30108@gmail.com> Date: Sat, 21 Feb 2009 14:43:29 +0100 From: phcoder User-Agent: Thunderbird 2.0.0.19 (X11/20090105) MIME-Version: 1.0 To: The development of GRUB 2 References: <499C7809.6030203@student.ethz.ch> <499D7526.70907@gmail.com> <20090219073836.2d532392@gibibit.com> <20090221133852.GI16068@thorin> In-Reply-To: <20090221133852.GI16068@thorin> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 2) 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 13:43:35 -0000 And in this scenario the encryption key would also be in flash. Since you can't boot unchecked software and normal linux security wouldn't allow you to read flash unless you have the root password you can't recover the key Regards Vladimir 'phcoder' Serbinenko Robert Millan wrote: > 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. >