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 45C46C33CAF for ; Thu, 16 Jan 2020 19:04:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 28E15206D7 for ; Thu, 16 Jan 2020 19:04:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730562AbgAPTEh (ORCPT ); Thu, 16 Jan 2020 14:04:37 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:33412 "EHLO mx0b-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388538AbgAPTEc (ORCPT ); Thu, 16 Jan 2020 14:04:32 -0500 Received: from pps.filterd (m0127361.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 00GJ3hlt055469 for ; Thu, 16 Jan 2020 14:04:31 -0500 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0a-001b2d01.pphosted.com with ESMTP id 2xhferckf9-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 16 Jan 2020 14:04:30 -0500 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 16 Jan 2020 19:04:27 -0000 Received: from b06cxnps4076.portsmouth.uk.ibm.com (9.149.109.198) by e06smtp05.uk.ibm.com (192.168.101.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 16 Jan 2020 19:04:25 -0000 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 00GJ4OtK38207536 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 16 Jan 2020 19:04:24 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 76B425205F; Thu, 16 Jan 2020 19:04:24 +0000 (GMT) Received: from dhcp-9-31-102-70.watson.ibm.com (unknown [9.31.102.70]) by d06av21.portsmouth.uk.ibm.com (Postfix) with ESMTP id 2275352052; Thu, 16 Jan 2020 19:04:24 +0000 (GMT) Subject: Re: Question on signing the IMA signing key for kernel trusted keyrings? From: Mimi Zohar To: Clay Chang , linux-integrity@vger.kernel.org Date: Thu, 16 Jan 2020 14:04:23 -0500 In-Reply-To: <20200116183918.GA14177@blofly.tw.rdlabs.hpecorp.net> References: <20200116183918.GA14177@blofly.tw.rdlabs.hpecorp.net> 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: 20011619-0020-0000-0000-000003A14A8B X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20011619-0021-0000-0000-000021F8CAA3 Message-Id: <1579201463.5857.38.camel@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-01-16_05:2020-01-16,2020-01-16 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 phishscore=0 impostorscore=0 mlxscore=0 bulkscore=0 lowpriorityscore=0 adultscore=0 priorityscore=1501 clxscore=1015 mlxlogscore=999 spamscore=0 suspectscore=3 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-2001160152 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Fri, 2020-01-17 at 02:39 +0800, Clay Chang wrote: > Hi, > > We know that IMA or EVM signing key must be signed by the .builtin_trusted_keys. > In the .builtin_trusted_keys keyring of a fresh CentOS, for example, > there are public keys created by CentOS. And the private key counterparts > were not available publicly. So I think there is technically no way for > others to sign the IMA or EVM key by the private keys of those CA. > > Is there a possibility of getting the IMA or EVM signing keys signed > (probably by the public key in .builtin_trusted_keys) without rolling own > CA and re-gen the kernel? If the kernel was built with CONFIG_SYSTEM_EXTRA_CERTIFICATE, the customer could insert their public key post build.[1]  This would obviously require the kernel to be resigned. I agree there needs to be a simpler way of including a customer key, without requiring them to resign the kernel. Mimi [1] c4c361059585 ("KEYS: Reserve an extra certificate symbol for inserting without recompiling")