From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1bZ03W-0003pE-RO for mharc-grub-devel@gnu.org; Sun, 14 Aug 2016 14:22:42 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33356) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bZ03U-0003nn-3x for grub-devel@gnu.org; Sun, 14 Aug 2016 14:22:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bZ03P-0007H6-1c for grub-devel@gnu.org; Sun, 14 Aug 2016 14:22:39 -0400 Received: from mout.gmx.net ([212.227.15.19]:55453) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bZ03O-0007GT-NS for grub-devel@gnu.org; Sun, 14 Aug 2016 14:22:34 -0400 Received: from scdbackup.webframe.org ([91.8.173.247]) by mail.gmx.com (mrgmx001) with ESMTPSA (Nemesis) id 0LtJAR-1bBWua2mPj-012p14 for ; Sun, 14 Aug 2016 20:22:31 +0200 Date: Sun, 14 Aug 2016 20:24:08 +0200 From: "Thomas Schmitt" To: grub-devel@gnu.org Subject: Re: Grub module to return partuuid of a device such as (hd0, gpt1) at boot time Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit References: In-Reply-To: Message-Id: <2801588618868301236@scdbackup.webframe.org> X-Provags-ID: V03:K0:Fv6+Kf+/Z/2Dh5STbMsXnrzFPfl6J84rlJ0e4SeEYa9YbfYXNxu 6tP7X45wZ8yH0sb5A4rlMM+PZxMCMzDpIDUhUnCRNvJ5+S0deobQa3L8o7uFvAWY/4U/2j2 Ip6cZyChndWDPf9b1sIzlbNghY1AwKDQzxtv4XOe+3wrLrurUfTzEcbgztrfUrwz3s7Dvvn +3qXLhVlCMWxy9zQ6hIkQ== X-UI-Out-Filterresults: notjunk:1;V01:K0:5zjXKRY1s2U=:VArHo+qHKSvsrSvJc1mdrd TDtuv3/UtZ8sHtN35hjqPtEVXV1u1lFYzzHofBrj7hhCndsnXYkniqDpB65z6X3NL9PEY138n wj7mpWtNaSNVDWEKIjUWV3DNPsQ7jwRYfNXVzyuBkElB4Ca6It9xf4wudDSVcrujc1gXDlnEl FiiAOkXsFUmTCCCdxT1npdzvA1jpPAeS+fn1jFUClT7cfLYydy9I6k3xvyrgqSLty0pQ8UHaA gSgj6QPsNtc537TDcmObKRbwkktL6xbnn56TMcXoYsfwWzKNPFg8fho5VaUb3RAbqWA7Q07Cv FBwrVnUuv9K+1zRFUbPVYU4wH10L3mgNGUroyXkYPORVBGH9T1f+Jg3dtgekaQN1PLmigunon K44bobUMZ0JEtiSbvjzTHJzSD2Do3mABBgg6afYytt605G31tiNT4gPfsosCFHsTPuQm5pXlF WtVZaPLOjAuDLLCAQrD7S9HeIxfdSv1dzlJ1IOx3QrLWZ6O3kEUgz8CLGm5bBx96K1mT59cpq weKuBwKq9N6nSXXZBUvMLKg2tmHeWLIyFWSuSjV1D5BDb4ncnDEdG4dO6T0AzLrydNglIm80n Qov3hezqyic43r7c4moqeMzlWeBqEgre1rI8l59nMbAw8YaQVbnjD4WNY+t+3J0Zq8H+BJW8i +yrkZxk7/YjnP3u4D4ZtiO4u94RA/vOd8Tpe7yxJSn74HfPLxLf/zezmuWI2sGkh1gtacd0to sSqpz1H5NqnJeg9x0QmN2SQn3VXTBNOuwAqHXtmG6WnlFCDAmkG5/6+YPCZcgXfAmCLVlFxuW XhQ0vQK X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 212.227.15.19 X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: The development of GNU GRUB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 14 Aug 2016 18:22:41 -0000 Hi, i riddled over UEFI appendix A: > > Do you mean that one has to interpret the statement of UEFI 2.4 > > "All EFI GUIDs (Globally Unique Identifiers) have the format described > > in RFC 4122 [...] > > It should also be noted that TimeLow, TimeMid, TimeHighAndVersion fields > > in the EFI are encoded as little endian." > > as > > The text format of EFI GUIDs is the same as in RFC 4122, but the binary > > representation is byte-swapped at the first 4, 2, and 2 bytes. Andrei Borzenkov wrote: > Yes. See other mail I just sent :) I have to give in, since i am not in the position to raise protest against Intel et.al. because of obfuscating english language. :)) > > Value "modification-date" produces a low > > quality GUID from the value set by option --modification-date=. > How? Time base UUID (Version 1) requires "node data" I am aware that the result is a poor fake of an UUID. Its time granularity is below any standard. No site id. So i let it pose as random. The reason for offering it is to reduce the number of parameters which one has to remember for reproducibly producing an ISO. (--modification-date= must be used in any case to override the automatic "now" timestamping of the ISO filesystem.) > > The partition GUIDs will be generated in a reproducible way by exoring a > > little-endian 32 bit counter with the disk GUID beginning at byte offset 9. > Not sure I follow - what counter? Partition number. I shall clarify this in the API. In result the GUID byte strings of a grub-mkrescue GPT will look like GPT disk GUID : 2303cd2a73c7424aa29825632da7f446 GPT partition GUID : 1 2303cd2a73c7424aa29925632da7f446 GPT partition GUID : 2 2303cd2a73c7424aa29a25632da7f446 GPT partition GUID : 3 2303cd2a73c7424aa29b25632da7f446 GPT partition GUID : 4 2303cd2a73c7424aa29c25632da7f446 In current xorriso, the first partition GUID is the original random and disk GUID is derived from it as last one: GPT disk GUID : 6d359a15f8763e47b9ee78207025c200 GPT partition GUID : 1 6d359a15f8763e47b9ea78207025c200 ... GPT partition GUID : 4 6d359a15f8763e47b9e978207025c200 > My copy of 2.4 RevC still does not mention IEEE 802 I have a PDF with title Unified Extensible Firmware Interface Specification Version 2.4 Errata B April, 2014 In appendix A, table 218, row "Node" i read: "Byte Offset: 10" "Byte Length: 6" "Description: The spatially unique node identifier. This can be based on any IEEE 802 address obtained from a network card. If no network card exists in the system, a cryptographic-quality random number can be used." > Yes it could be more clear. They should pay you a reward for compensating this flaw. Have a nice day :) Thomas