From patchwork Wed Sep 5 11:41:59 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 10588827 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5A2CB5A4 for ; Wed, 5 Sep 2018 11:59:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3B44A29B38 for ; Wed, 5 Sep 2018 11:59:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2FB7529B4E; Wed, 5 Sep 2018 11:59:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CAAEA29B38 for ; Wed, 5 Sep 2018 11:59:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726361AbeIEQ27 (ORCPT ); Wed, 5 Sep 2018 12:28:59 -0400 Received: from lhrrgout.huawei.com ([185.176.76.210]:2066 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726340AbeIEQ27 (ORCPT ); Wed, 5 Sep 2018 12:28:59 -0400 X-Greylist: delayed 911 seconds by postgrey-1.27 at vger.kernel.org; Wed, 05 Sep 2018 12:28:58 EDT Received: from lhreml705-cah.china.huawei.com (unknown [172.18.7.107]) by Forcepoint Email with ESMTP id A560E6C3DE292 for ; Wed, 5 Sep 2018 12:43:53 +0100 (IST) Received: from roberto-HP-EliteDesk-800-G2-DM-65W.huawei.com (10.204.65.153) by smtpsuk.huawei.com (10.201.108.46) with Microsoft SMTP Server (TLS) id 14.3.399.0; Wed, 5 Sep 2018 12:43:47 +0100 From: Roberto Sassu To: CC: Roberto Sassu Subject: [PATCH v2 0/3] tpm: retrieve digest size of unknown algorithms from TPM Date: Wed, 5 Sep 2018 13:41:59 +0200 Message-ID: <20180905114202.7757-1-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.14.1 MIME-Version: 1.0 X-Originating-IP: [10.204.65.153] X-CFilter-Loop: Reflected Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The TPM driver currently relies on the crypto subsystem to determine the digest size of supported TPM algorithms. In the future, TPM vendors might implement new algorithms in their chips, and those algorithms might not be supported by the crypto subsystem. Usually, vendors provide patches for the new hardware, and likely the crypto subsystem will be updated before the new algorithm is introduced. However, old kernels might be updated later, after patches are included in the mainline kernel. This would leave the opportunity for attackers to misuse PCRs, as PCR banks with an unknown algorithm are not extended. This patch set provides a long term solution for this issue. If a TPM algorithm is not known by the crypto subsystem, the TPM driver retrieves the digest size from the TPM with a PCR read. All the PCR banks are extended, even if the algorithm is not yet supported by the crypto subsystem. Roberto Sassu (3): tpm: rename and export tpm2_digest and tpm2_algorithms tpm: modify tpm_pcr_read() definition to pass TPM hash algorithms tpm: retrieve digest size of unknown algorithms with PCR read drivers/char/tpm/tpm-interface.c | 24 ++++++++---- drivers/char/tpm/tpm.h | 18 ++------- drivers/char/tpm/tpm2-cmd.c | 78 +++++++++++++++++++++++++------------ include/linux/tpm.h | 30 +++++++++++++- include/linux/tpm_eventlog.h | 9 +---- security/integrity/ima/ima_crypto.c | 10 ++--- 6 files changed, 109 insertions(+), 60 deletions(-)