linux-kernel - Re: [GIT PULL] Load keys from signed PE binaries

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87lia8nsti.fsf@mid.deneb.enyo.de>
Date:	Thu, 28 Feb 2013 20:26:17 +0100
From:	Florian Weimer <fw@...eb.enyo.de>
To:	Chris Friesen <chris.friesen@...band.com>
Cc:	Greg KH <gregkh@...uxfoundation.org>,
	Matthew Garrett <mjg59@...f.ucam.org>,
	David Howells <dhowells@...hat.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Josh Boyer <jwboyer@...hat.com>,
	Peter Jones <pjones@...hat.com>,
	Vivek Goyal <vgoyal@...hat.com>,
	Kees Cook <keescook@...omium.org>, keyrings@...ux-nfs.org,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [GIT PULL] Load keys from signed PE binaries

* Chris Friesen:

> On 02/28/2013 01:57 AM, Florian Weimer wrote:
>
>> In any case, there's another reading of the UEFI Secure Boot
>> requirements: you may run any code you wish after calling
>> ExitBootServices().  That could be an unsigned, traditional GRUB.  But
>> this will not generally address the issue of dual-booting Windows 8 in
>> such a way that Windows sees that the device has enabled Microsoft
>> Secure Boot.
>
> Would it be possible to have a signed bootloader that allows booting
> Win8 from within the secure environment, or it could exit the secure
> environment and run unsigned grub?

On systems where the firmware supports multiple boot loaders, this
would work.

On systems which support just one boot loader, the next-stage boot
loader could be signed or not, it would not have access to the
privileged Secure Boot environment.  The decision to boot the
Secure-Boot-capable operating system would have to be made before
calling ExitBootServices(), otherwise that operating system will not
see Secure Boot support.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/