Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752474AbbETHpq (ORCPT ); Wed, 20 May 2015 03:45:46 -0400 Received: from cantor2.suse.de ([195.135.220.15]:48390 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751184AbbETHpn (ORCPT ); Wed, 20 May 2015 03:45:43 -0400 Message-ID: <555C3B99.4000000@suse.cz> Date: Wed, 20 May 2015 15:45:29 +0800 From: Michal Marek User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Jiri Kosina , David Howells CC: "Theodore Ts'o" , Andy Lutomirski , Andy Lutomirski , Linus Torvalds , David Woodhouse , Abelardo Ricart III , Linux Kernel Mailing List , Sedat Dilek , keyrings@linux-nfs.org, Rusty Russell , LSM List , Borislav Petkov Subject: Re: Should we automatically generate a module signing key at all? References: <20150519155532.GB2871@thunk.org> <31154.1431965087@warthog.procyon.org.uk> <555A88FB.7000809@kernel.org> <29742.1432025631@warthog.procyon.org.uk> <1752.1432049417@warthog.procyon.org.uk> <3253.1432052599@warthog.procyon.org.uk> In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1185 Lines: 25 Dne 20.5.2015 v 05:47 Jiri Kosina napsal(a): > On Tue, 19 May 2015, David Howells wrote: > >> That wouldn't very convenient for building our kernels in our build farm >> - we have a lot of machines and all of them would have to be equiped >> with the key. Besides, we *want* to discard the private key where >> possible as soon as possible because then we can't leak it and we can't >> be forced to disclose it. > > You can still have a dedicated machine that's used just for signing the > binaries. That machine wouldn't be connected to the network, would be > physically secured, and would sign through a serial line or so. Right, that's what CONFIG_MODULE_SIG_ALL=n is meant for -- build the public key into the kernel, but sign the modules later, outside of the build system. So you still have to trust the build machine to build what you ask it to build, but you do not have to trust it not to leak your private key. Michal -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/