Return-path: Received: from e28smtp06.in.ibm.com ([122.248.162.6]:50363 "EHLO e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751275AbbESVst (ORCPT ); Tue, 19 May 2015 17:48:49 -0400 Received: from /spool/local by e28smtp06.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 20 May 2015 03:18:47 +0530 Message-ID: <1432072117.4510.180.camel@linux.vnet.ibm.com> (sfid-20150519_234907_113132_84CCA78C) Subject: Re: [RFD] linux-firmware key arrangement for firmware signing From: Mimi Zohar To: "Luis R. Rodriguez" Cc: linux-security-module@vger.kernel.org, james.l.morris@oracle.com, serge@hallyn.com, linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org, David Howells , Kyle McMartin , David Woodhouse , Seth Forshee , Greg Kroah-Hartman , Joey Lee , Rusty Russell , mricon@kernel.org, Kees Cook Date: Tue, 19 May 2015 17:48:37 -0400 In-Reply-To: <20150519200232.GM23057@wotan.suse.de> References: <20150519200232.GM23057@wotan.suse.de> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, 2015-05-19 at 22:02 +0200, Luis R. Rodriguez wrote: > David Howells has posted v4 of his series of supporting PKCS#7 for module > signing. I'm in my v3 series now on RFCs for firmware PKCS#7 support, and after > some review and patch shuffling I think this is ready for patch form. My own > series however depend on quite a bit of other pending changes, one series which > will go through Rusty's tree, another series of fixes on firmware_class which > should go through Greg's tree. I'll wait until all this and David's own patches > get merged before posting firmware PKCS#7 support. Before all this though in > preparation for fw signing one thing we should start to talk about more broadly > however is how linux-firmware binary file signing would work in practice and > what we need, and make sure folks are OK with all this. Commit 13752fe "security: introduce kernel_fw_from_file hook" introduced a new security hook. (IMA is on this hook as well.) Have you considered using this hook? Are there other places that this hook would need to be called? > I think we need one change here, we'd need to ensure that such key could only > be used for vetting firmware files, not modules loaded. The firmware_class > could for instance still use all the keys in system_trusted_keyring, which > would include the UEFI key db, but it does not seems reasonable to expect keys > used for fw signing to also go into system_trusted_keyring to also be used for > module signing. I agree totally! For this reason, IMA defined a separate trusted keyring to be used for verifying file signatures. Mimi > Other than this last nitpick, any other concerns or recommendations ? > > [0] https://wireless.wiki.kernel.org/en/developers/regulatory/crda > > Luis