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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 8BEBBC4CEC9 for ; Fri, 20 Sep 2019 14:18:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 63B1D207E0 for ; Fri, 20 Sep 2019 14:18:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387779AbfITOSa (ORCPT ); Fri, 20 Sep 2019 10:18:30 -0400 Received: from mga09.intel.com ([134.134.136.24]:35096 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387773AbfITOSa (ORCPT ); Fri, 20 Sep 2019 10:18:30 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Sep 2019 07:18:29 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,528,1559545200"; d="scan'208";a="194706214" Received: from eergin-mobl.ger.corp.intel.com (HELO localhost) ([10.252.40.12]) by FMSMGA003.fm.intel.com with ESMTP; 20 Sep 2019 07:18:27 -0700 Date: Fri, 20 Sep 2019 17:18:26 +0300 From: Jarkko Sakkinen To: James Bottomley Cc: linux-integrity@vger.kernel.org, linux-crypto@vger.kernel.org, linux-security-module@vger.kernel.org Subject: Re: [PATCH v6 02/12] tpm-buf: add handling for TPM2B types Message-ID: <20190920141826.GC9578@linux.intel.com> References: <1568031408.6613.29.camel@HansenPartnership.com> <1568031515.6613.31.camel@HansenPartnership.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1568031515.6613.31.camel@HansenPartnership.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Mon, Sep 09, 2019 at 01:18:35PM +0100, James Bottomley wrote: > Most complex TPM commands require appending TPM2B buffers to the > command body. Since TPM2B types are essentially variable size arrays, > it makes it impossible to represent these complex command arguments as > structures and we simply have to build them up using append primitives > like these. > > Signed-off-by: James Bottomley I think a better idea would be to have headerless TPM buffers and also it makes sense to have a separate length field in the struct to keep the code sane given that sometimes the buffer does not store the length. E.g. enum tpm_buf_flags { TPM_BUF_OVERFLOW = BIT(0), TPM_BUF_HEADERLESS = BIT(1), }; struct tpm_buf { unsigned int length; struct page *data_page; unsigned int flags; u8 *data; }; /Jarkko