From patchwork Wed Jun 21 14:29:36 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 778915 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.sourceforge.net (lists.sourceforge.net [216.34.181.88]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3wt6d42ChPz9s5L for ; Thu, 22 Jun 2017 00:32:56 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=sourceforge.net header.i=@sourceforge.net header.b="C0GreiYr"; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=sf.net header.i=@sf.net header.b="NW4+bKjL"; dkim-atps=neutral Received: from localhost ([127.0.0.1] helo=sfs-ml-2.v29.ch3.sourceforge.com) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1dNggc-00063C-8O; Wed, 21 Jun 2017 14:32:50 +0000 Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1dNggb-000634-6I; Wed, 21 Jun 2017 14:32:49 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=EtC8xx7cDIvD+4wOMZYBidQCqzV5I41J+qr6Gk5QKrU=; b=C0GreiYrCS5FZpsWO4EIahv053I8Hil5lya0G+TT0fXcVliIhskPAJDbMqZNcLIDY6p9tq6FYc0IRhOXsJlsfKh4YQtE62+uKSgudSbRYFvuiXmCtQQ7XDJLPooE98K0q+yIbYXBlmG/3h1ov5i8DtyLHO4EuZTMQN503CJMTzM=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x; h=Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=EtC8xx7cDIvD+4wOMZYBidQCqzV5I41J+qr6Gk5QKrU=; b=NW4+bKjLcH1Z1qqt3NJGdzEOkY/SdmC7IeMKpbyuVra/zE9oLIiE0h4tRKDKPYLQFUVwVW2g9Il98pE2+q/71+0v4YMK7rLQw6ynvEZwtn/5tl1pUip1a85t1yXBphWMJvCFOV/rQHfOTU2ov6OW/SlemmuNLiz0BDK95qSLvI0=; Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of huawei.com designates 194.213.3.17 as permitted sender) client-ip=194.213.3.17; envelope-from=roberto.sassu@huawei.com; helo=lhrrgout.huawei.com; Received: from lhrrgout.huawei.com ([194.213.3.17]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1dNggX-0008NY-Ee; Wed, 21 Jun 2017 14:32:49 +0000 Received: from 172.18.7.190 (EHLO LHREML711-CAH.china.huawei.com) ([172.18.7.190]) by lhrrg02-dlp.huawei.com (MOS 4.3.7-GA FastPath queued) with ESMTP id DIY23247; Wed, 21 Jun 2017 14:32:35 +0000 (GMT) Received: from roberto-HP-EliteDesk-800-G2-DM-65W.huawei.com (10.204.65.245) by smtpsuk.huawei.com (10.201.108.34) with Microsoft SMTP Server (TLS) id 14.3.301.0; Wed, 21 Jun 2017 15:32:24 +0100 From: Roberto Sassu To: Date: Wed, 21 Jun 2017 16:29:36 +0200 Message-ID: <20170621142941.32674-2-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20170621142941.32674-1-roberto.sassu@huawei.com> References: <20170621142941.32674-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.65.245] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.594A8383.032A, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: b6e705b68c1581613437862ee1f58501 X-Spam-Score: -1.5 (-) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.0 SPF_PASS SPF: sender matches SPF record X-Headers-End: 1dNggX-0008NY-Ee Subject: [tpmdd-devel] [PATCH v3 1/6] tpm: use tpm_buf functions to perform a PCR read X-BeenThere: tpmdd-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: Tpm Device Driver maintainance List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-ima-devel@lists.sourceforge.net, linux-security-module@vger.kernel.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org Errors-To: tpmdd-devel-bounces@lists.sourceforge.net tpm2_pcr_read() now uses tpm_buf functions to build the TPM command to read a PCR. Those functions are preferred to passing a tpm2_cmd structure, as they provide protection against buffer overflow. Also, tpm2_pcr_read() code has been moved to tpm2_pcr_read_tpm_buf(). Callers have to pass a tpm_buf structure, an algorithm supported by the TPM and call tpm_buf_destroy(). The algorithm still cannot be passed to the TPM driver interface. This parameter has been introduced for determining the digest size of a given algorithm. Moving tpm2_pcr_read() code to tpm2_pcr_read_tpm_buf() is necessary because callers of the new function obtain different information from the output buffer: tpm2_pcr_read() gets the digest, tpm2_do_selftest() will get the command return code and tpm2_get_pcr_allocation() will get the digest size. Signed-off-by: Roberto Sassu --- drivers/char/tpm/tpm2-cmd.c | 54 +++++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 22 deletions(-) diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 3a99643..afd1b63 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -231,15 +231,37 @@ static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = { (sizeof(struct tpm_input_header) + \ sizeof(struct tpm2_pcr_read_in)) -#define TPM2_PCR_READ_RESP_BODY_SIZE \ - sizeof(struct tpm2_pcr_read_out) - static const struct tpm_input_header tpm2_pcrread_header = { .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS), .length = cpu_to_be32(TPM2_PCR_READ_IN_SIZE), .ordinal = cpu_to_be32(TPM2_CC_PCR_READ) }; +static int tpm2_pcr_read_tpm_buf(struct tpm_chip *chip, int pcr_idx, + enum tpm2_algorithms algo, struct tpm_buf *buf, + char *msg) +{ + int rc; + u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0}; + + if (pcr_idx >= TPM2_PLATFORM_PCR) + return -EINVAL; + + rc = tpm_buf_init(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ); + if (rc) + return rc; + + pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7); + + tpm_buf_append_u32(buf, 1); + tpm_buf_append_u16(buf, algo); + tpm_buf_append_u8(buf, TPM2_PCR_SELECT_MIN); + tpm_buf_append(buf, (const unsigned char *)pcr_select, + sizeof(pcr_select)); + + return tpm_transmit_cmd(chip, NULL, buf->data, PAGE_SIZE, 0, 0, msg); +} + /** * tpm2_pcr_read() - read a PCR value * @chip: TPM chip to use. @@ -251,29 +273,17 @@ static const struct tpm_input_header tpm2_pcrread_header = { int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) { int rc; - struct tpm2_cmd cmd; - u8 *buf; - - if (pcr_idx >= TPM2_PLATFORM_PCR) - return -EINVAL; - - cmd.header.in = tpm2_pcrread_header; - cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1); - cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1); - cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN; - - memset(cmd.params.pcrread_in.pcr_select, 0, - sizeof(cmd.params.pcrread_in.pcr_select)); - cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7); + struct tpm_buf buf; + struct tpm2_pcr_read_out *out; - rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), - TPM2_PCR_READ_RESP_BODY_SIZE, - 0, "attempting to read a pcr value"); + rc = tpm2_pcr_read_tpm_buf(chip, pcr_idx, TPM2_ALG_SHA1, &buf, + "attempting to read a pcr value"); if (rc == 0) { - buf = cmd.params.pcrread_out.digest; - memcpy(res_buf, buf, TPM_DIGEST_SIZE); + out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE]; + memcpy(res_buf, out->digest, TPM_DIGEST_SIZE); } + tpm_buf_destroy(&buf); return rc; }