From patchwork Sun Nov 10 16:21:34 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amir Mizinski X-Patchwork-Id: 11236257 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A705E17E6 for ; Sun, 10 Nov 2019 16:33:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 85C002184C for ; Sun, 10 Nov 2019 16:33:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727133AbfKJQda (ORCPT ); Sun, 10 Nov 2019 11:33:30 -0500 Received: from 212.199.177.27.static.012.net.il ([212.199.177.27]:44397 "EHLO herzl.nuvoton.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727097AbfKJQda (ORCPT ); Sun, 10 Nov 2019 11:33:30 -0500 X-Greylist: delayed 642 seconds by postgrey-1.27 at vger.kernel.org; Sun, 10 Nov 2019 11:33:15 EST Received: from taln60.nuvoton.co.il (ntil-fw [212.199.177.25]) by herzl.nuvoton.co.il (8.13.8/8.13.8) with ESMTP id xAAGMMNU013903; Sun, 10 Nov 2019 18:22:22 +0200 Received: by taln60.nuvoton.co.il (Postfix, from userid 10140) id 7B50160275; Sun, 10 Nov 2019 18:22:22 +0200 (IST) From: amirmizi6@gmail.com To: Eyal.Cohen@nuvoton.com, jarkko.sakkinen@linux.intel.com, oshrialkoby85@gmail.com, alexander.steffen@infineon.com, robh+dt@kernel.org, mark.rutland@arm.com, peterhuewe@gmx.de, jgg@ziepe.ca, arnd@arndb.de, gregkh@linuxfoundation.org Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, oshri.alkoby@nuvoton.com, tmaimon77@gmail.com, gcwilson@us.ibm.com, kgoldman@us.ibm.com, ayna@linux.vnet.ibm.com, Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com, shmulik.hagar@nuvoton.com, amir.mizinski@nuvoton.com, Amir Mizinski Subject: [PATCH v1 2/5] char: tpm: Add check_data handle to tpm_tis_phy_ops in order to check data integrity Date: Sun, 10 Nov 2019 18:21:34 +0200 Message-Id: <20191110162137.230913-3-amirmizi6@gmail.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20191110162137.230913-1-amirmizi6@gmail.com> References: <20191110162137.230913-1-amirmizi6@gmail.com> MIME-Version: 1.0 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Amir Mizinski The current principles: - When sending command: 1. Host writes TPM_STS.commandReady 2. Host writes command 3. Host checks TPM received data correctly 4. if not go to step 1 - When receiving data: 1. Host check TPM_STS.dataAvail is set 2. Host get data 3. Host check received data are correct. 4. if not Host write TPM_STS.responseRetry and go to step 1. this commit is based on previous work by Christophe Richard Signed-off-by: Amir Mizinski --- drivers/char/tpm/tpm_tis_core.c | 97 +++++++++++++++++++++++++---------------- drivers/char/tpm/tpm_tis_core.h | 3 ++ 2 files changed, 62 insertions(+), 38 deletions(-) diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index c3181ea..ce7f8a1 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -242,6 +242,15 @@ static u8 tpm_tis_status(struct tpm_chip *chip) return status; } +static bool tpm_tis_check_data(struct tpm_chip *chip, const u8 *buf, size_t len) +{ + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + + if (priv->phy_ops->check_data) + return priv->phy_ops->check_data(priv, buf, len); + return true; +} + static void tpm_tis_ready(struct tpm_chip *chip) { struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); @@ -308,47 +317,55 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count) { struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); int size = 0; - int status; + int status, i; u32 expected; + bool check_data = false; - if (count < TPM_HEADER_SIZE) { - size = -EIO; - goto out; - } + for (i = 0; i < TPM_RETRY && !check_data; i++) { + if (count < TPM_HEADER_SIZE) { + size = -EIO; + goto out; + } - size = recv_data(chip, buf, TPM_HEADER_SIZE); - /* read first 10 bytes, including tag, paramsize, and result */ - if (size < TPM_HEADER_SIZE) { - dev_err(&chip->dev, "Unable to read header\n"); - goto out; - } + size = recv_data(chip, buf, TPM_HEADER_SIZE); + /* read first 10 bytes, including tag, paramsize, and result */ + if (size < TPM_HEADER_SIZE) { + dev_err(&chip->dev, "Unable to read header\n"); + goto out; + } - expected = be32_to_cpu(*(__be32 *) (buf + 2)); - if (expected > count || expected < TPM_HEADER_SIZE) { - size = -EIO; - goto out; - } + expected = be32_to_cpu(*(__be32 *) (buf + 2)); + if (expected > count || expected < TPM_HEADER_SIZE) { + size = -EIO; + goto out; + } - size += recv_data(chip, &buf[TPM_HEADER_SIZE], - expected - TPM_HEADER_SIZE); - if (size < expected) { - dev_err(&chip->dev, "Unable to read remainder of result\n"); - size = -ETIME; - goto out; - } + size += recv_data(chip, &buf[TPM_HEADER_SIZE], + expected - TPM_HEADER_SIZE); + if (size < expected) { + dev_err(&chip->dev, "Unable to read remainder of result\n"); + size = -ETIME; + goto out; + } - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, - &priv->int_queue, false) < 0) { - size = -ETIME; - goto out; - } - status = tpm_tis_status(chip); - if (status & TPM_STS_DATA_AVAIL) { /* retry? */ - dev_err(&chip->dev, "Error left over data\n"); - size = -EIO; - goto out; - } + if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, + &priv->int_queue, false) < 0) { + size = -ETIME; + goto out; + } + + status = tpm_tis_status(chip); + if (status & TPM_STS_DATA_AVAIL) { /* retry? */ + dev_err(&chip->dev, "Error left over data\n"); + size = -EIO; + goto out; + } + check_data = tpm_tis_check_data(chip, buf, size); + if (!check_data) + tpm_tis_write8(priv, TPM_STS(priv->locality), + TPM_STS_RESPONSE_RETRY); + } out: tpm_tis_ready(chip); return size; @@ -453,13 +470,17 @@ static void disable_interrupts(struct tpm_chip *chip) static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len) { struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); - int rc; + int rc, i; u32 ordinal; unsigned long dur; + bool data_valid = false; - rc = tpm_tis_send_data(chip, buf, len); - if (rc < 0) - return rc; + for (i = 0; i < TPM_RETRY && !data_valid; i++) { + rc = tpm_tis_send_data(chip, buf, len); + if (rc < 0) + return rc; + data_valid = tpm_tis_check_data(chip, buf, len); + } /* go and do it */ rc = tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_GO); diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h index d06c65b..486c2e9 100644 --- a/drivers/char/tpm/tpm_tis_core.h +++ b/drivers/char/tpm/tpm_tis_core.h @@ -34,6 +34,7 @@ enum tis_status { TPM_STS_GO = 0x20, TPM_STS_DATA_AVAIL = 0x10, TPM_STS_DATA_EXPECT = 0x08, + TPM_STS_RESPONSE_RETRY = 0x02, }; enum tis_int_flags { @@ -106,6 +107,8 @@ struct tpm_tis_phy_ops { int (*read16)(struct tpm_tis_data *data, u32 addr, u16 *result); int (*read32)(struct tpm_tis_data *data, u32 addr, u32 *result); int (*write32)(struct tpm_tis_data *data, u32 addr, u32 src); + bool (*check_data)(struct tpm_tis_data *data, const u8 *buf, + size_t len); }; static inline int tpm_tis_read_bytes(struct tpm_tis_data *data, u32 addr,