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=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 77D35C43381 for ; Fri, 22 Mar 2019 10:12:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 45412218D3 for ; Fri, 22 Mar 2019 10:12:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728043AbfCVKMf (ORCPT ); Fri, 22 Mar 2019 06:12:35 -0400 Received: from mga06.intel.com ([134.134.136.31]:49211 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727858AbfCVKMf (ORCPT ); Fri, 22 Mar 2019 06:12:35 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 22 Mar 2019 03:12:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,256,1549958400"; d="scan'208";a="124918269" Received: from vanderss-mobl1.ger.corp.intel.com (HELO localhost) ([10.249.254.199]) by orsmga007.jf.intel.com with ESMTP; 22 Mar 2019 03:12:29 -0700 Date: Fri, 22 Mar 2019 12:12:27 +0200 From: Jarkko Sakkinen To: Roberto Sassu Cc: Dan Williams , James Bottomley , Mimi Zohar , David Howells , keyrings@vger.kernel.org, linux-nvdimm , Linux Kernel Mailing List , Silviu Vlasceanu Subject: Re: [PATCH] security/keys/trusted: Allow operation without hardware TPM Message-ID: <20190322101227.GB3122@linux.intel.com> References: <155295271345.1945351.6465460744078693578.stgit@dwillia2-desk3.amr.corp.intel.com> <20190321135451.GD4603@linux.intel.com> <809e827b-fdbe-fbb8-8acf-2878ae9f7777@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 21, 2019 at 06:45:47PM +0100, Roberto Sassu wrote: > On 3/21/2019 5:30 PM, Dan Williams wrote: > > On Thu, Mar 21, 2019 at 7:27 AM Roberto Sassu wrote: > > > > > > On 3/21/2019 2:54 PM, Jarkko Sakkinen wrote: > > > > On Mon, Mar 18, 2019 at 04:45:13PM -0700, Dan Williams wrote: > > > > > Rather than fail initialization of the trusted.ko module, arrange for > > > > > the module to load, but rely on trusted_instantiate() to fail > > > > > trusted-key operations. > > > > > > > > > > Fixes: 240730437deb ("KEYS: trusted: explicitly use tpm_chip structure...") > > > > > Cc: Roberto Sassu > > > > > Cc: Jarkko Sakkinen > > > > > Cc: James Bottomley > > > > > Cc: Jarkko Sakkinen > > > > > Cc: Mimi Zohar > > > > > Cc: David Howells > > > > > Signed-off-by: Dan Williams > > > > > > > > It should check for chip in each function that uses TPM now that > > > > the code does not rely on default chip. Otherwise, the semantics > > > > are kind of inconsistent. > > > > > > If no other TPM function can be used before a successful key > > > instantiate, checking for a chip only in trusted_instantiate() seems > > > sufficient. Then, the same chip will be used by all TPM functions until > > > module unloading, since we incremented the reference count. > > > > > > I would suggest to move the tpm_default_chip() and init_digests() calls > > > to trusted_instantiate() to restore the old behavior of init_trusted(). > > > > > > trusted_instantiate() should look like: > > > --- > > > if (!chip) { > > > chip = tpm_default_chip(); > > > if (!chip) > > > return -ENODEV; > > > } > > > > > > if (!digests) { > > > ret = init_digests(); > > > if (ret < 0) > > > return ret; > > > } > > > > This patch already achieves that because tpm_find_get_ops() will fail > > and cause tpm_is_tpm2() to return NULL. > > In addition, the changes I proposed would allow users to create trusted > keys if a TPM is added later. CONFIG_TRUSTED_KEYS=y and > CONFIG_TCG_TPM=m is a valid configuration. > > Jarkko, Dan's patch seems sufficient to fix the issue. He could include > the changes I proposed in his patch. What is your opinion? Agreed. /Jarkko