From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 163CCC49ED7 for ; Mon, 16 Sep 2019 22:13:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DC77B214D9 for ; Mon, 16 Sep 2019 22:13:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729108AbfIPWNL (ORCPT ); Mon, 16 Sep 2019 18:13:11 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:34438 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727719AbfIPWNL (ORCPT ); Mon, 16 Sep 2019 18:13:11 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8GM2MqO054375 for ; Mon, 16 Sep 2019 18:13:09 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0b-001b2d01.pphosted.com with ESMTP id 2v2h81khju-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 16 Sep 2019 18:13:09 -0400 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 16 Sep 2019 23:13:04 +0100 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8GMCcq642664314 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 16 Sep 2019 22:12:38 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E69394C046; Mon, 16 Sep 2019 22:13:03 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 60F084C040; Mon, 16 Sep 2019 22:13:03 +0000 (GMT) Received: from dhcp-9-31-103-196.watson.ibm.com (unknown [9.31.103.196]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 16 Sep 2019 22:13:03 +0000 (GMT) Subject: Re: [GIT PULL] integrity subsystem updates for v5.4 From: Mimi Zohar To: Linus Torvalds Cc: linux-security-module , linux-integrity , linux-kernel Date: Mon, 16 Sep 2019 18:13:02 -0400 In-Reply-To: References: <1568237365.5783.39.camel@linux.ibm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.20.5 (3.20.5-1.fc24) Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19091622-0028-0000-0000-0000039DCB45 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19091622-0029-0000-0000-0000246041D0 Message-Id: <1568671982.4975.145.camel@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-09-16_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=3 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909160210 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Mon, 2019-09-16 at 13:38 -0700, Linus Torvalds wrote: > On Wed, Sep 11, 2019 at 2:29 PM Mimi Zohar wrote: > > > > The major feature in this pull request is IMA support for measuring > > and appraising appended file signatures. In addition are a couple of > > bug fixes and code cleanup to use struct_size(). > > How is the file signature any different from (and/or better than) the > fs-verity support? > > The fs-verity support got fairly extensively discussed, and is > apparently going to actually be widely used by Android, and it an > independent feature of any security model. > > What does the IMA version bring to the table? IMA currently defines a system wide policy for measuring, verifying a file's integrity (both mutable/immutable files) against known good values, and adding audit records containing the file hashes.  The policy isn't hard coded in the kernel, allowing people/companies to configure it as desired for their specific use case. Support for appended signatures already exists in the kernel for kernel modules.  This pull request adds IMA support for appended signatures in order to verify the kexec kernel image on OpenPOWER, as part of Secure and Trusted boot enablement.  This would allow distros to sign kernel images similar to how they currently sign kernel modules. IMA verifies file signatures up front, before allowing access to the file.  fs-verity verifies the signature of the Merkle tree (and other info), but does not verify the file data at the time of first use.  There are pros and cons to each of these approaches. Mimi