From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754020Ab3BUUId (ORCPT ); Thu, 21 Feb 2013 15:08:33 -0500 Received: from li9-11.members.linode.com ([67.18.176.11]:49327 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753367Ab3BUUIa (ORCPT ); Thu, 21 Feb 2013 15:08:30 -0500 Date: Thu, 21 Feb 2013 15:08:22 -0500 From: "Theodore Ts'o" To: David Howells Cc: Linus Torvalds , Matthew Garrett , Josh Boyer , Peter Jones , Vivek Goyal , Kees Cook , keyrings@linux-nfs.org, Linux Kernel Mailing List Subject: Re: [GIT PULL] Load keys from signed PE binaries Message-ID: <20130221200822.GD17322@thunk.org> Mail-Followup-To: Theodore Ts'o , David Howells , Linus Torvalds , Matthew Garrett , Josh Boyer , Peter Jones , Vivek Goyal , Kees Cook , keyrings@linux-nfs.org, Linux Kernel Mailing List References: <30665.1361461678@warthog.procyon.org.uk> <20130221164244.GA19625@srcf.ucam.org> <567.1361470653@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <567.1361470653@warthog.procyon.org.uk> User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 21, 2013 at 06:17:33PM +0000, David Howells wrote: > > There's a problem with your idea. > > (1) Microsoft's revocation certificates would be based on the hash of the PE > binary, not the key. > > (2) Re-signing would make the keys then dependent on our master key rather > than directly on Microsoft's. Microsoft's revocation certificates[*] > would then be useless. > > (3) The only way Microsoft could then revoke the extra keys would be to > revoke our *master* key. Well, this hypothetical service could also simply scan the Microsoft revocation certificates (aka CRL's), and if the service detects a PE hash that it relied upon to resign the module, it could then issue its own CRL revoking the signature on the module. If it is run this way, programmatically, I'll note that anyone can run this service. It doesn't have to be Red Hat. It could be Linux Foundation, if the LF wanted to support this whole code signing insanity. (Which I really think is completely overblown, and I'm going to be amused when this blows to hell all of Red Hat's investments in Systemtap, but whatever.) Given that I think this whole thing is insane, I completely agree with Linus's attempt to keep this insanity as far away from the upstream kernel as we can. :-/ - Ted