From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754474Ab3AUSc3 (ORCPT ); Mon, 21 Jan 2013 13:32:29 -0500 Received: from e9.ny.us.ibm.com ([32.97.182.139]:56292 "EHLO e9.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752599Ab3AUSc1 (ORCPT ); Mon, 21 Jan 2013 13:32:27 -0500 Message-ID: <1358793007.2406.133.camel@falcor1.watson.ibm.com> Subject: Re: [PATCH 2/3] binfmt_elf: Verify signature of signed elf binary From: Mimi Zohar To: Vivek Goyal Cc: "Eric W. Biederman" , linux-kernel@vger.kernel.org, pjones@redhat.com, hpa@zytor.com, dhowells@redhat.com, jwboyer@redhat.com Date: Mon, 21 Jan 2013 13:30:07 -0500 In-Reply-To: <20130121164213.GB27617@redhat.com> References: <1358285695-26173-1-git-send-email-vgoyal@redhat.com> <1358285695-26173-3-git-send-email-vgoyal@redhat.com> <871udloiku.fsf@xmission.com> <1358312159.4593.37.camel@falcor1> <20130121164213.GB27617@redhat.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 (3.2.3-3.fc16) Content-Transfer-Encoding: 7bit Mime-Version: 1.0 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13012118-7182-0000-0000-00000497117D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2013-01-21 at 11:42 -0500, Vivek Goyal wrote: > On Tue, Jan 15, 2013 at 11:55:59PM -0500, Mimi Zohar wrote: > > [..] > > Please remind me why you can't use IMA-appraisal, which was upstreamed > > in Linux 3.7? Why another method is needed? > > So is this IMA-appraisal also supports digital signatures? The IMA white > paper seems to put digital signatures in separate category > (IMA-Appraisal-Signature-Extension). The white paper was written a couple of years ago, before either EVM or IMA-appraisal were upstreamed. - Linux 3.2: Extended Verification Module (EVM) - protects file metadata from offline modification - Linux 3.3: Dmitry Kasatkin's digital signature verification for use with EVM/IMA-appraisal. - Linux 3.7: IMA-appraisal/with digital signatures > > With IMA-appraisal, there are a couple of issues that would still need > > to be addressed: > > - missing the ability to specify the validation method required. Patches to address this issue are available from linux-integrity-test/ #next-ima-appraise-status and were posted on the LSM mailing list as an RFC (12/18/2012). Review of these patches would be appreciated. > > - modify the ima_appraise_tcb policy policy to require elf executables > > to be digitally signed. > > For my use case, all executable don't have to be digitally signed. If > something is digitally signed then do the signature verification. We already discussed this. Hard coding policy into the Linux kernel is wrong. thanks, Mimi