From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753037AbcGMQUg (ORCPT ); Wed, 13 Jul 2016 12:20:36 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:34670 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752879AbcGMQUY (ORCPT ); Wed, 13 Jul 2016 12:20:24 -0400 From: Ed Swierk To: tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org Cc: jarkko.sakkinen@linux.intel.com, jgunthorpe@obsidianresearch.com, stefanb@us.ibm.com, eswierk@skyportsystems.com Subject: [PATCH v9 4/5] tpm: Allow TPM chip drivers to override reported command durations Date: Wed, 13 Jul 2016 09:19:35 -0700 Message-Id: <1468426776-42762-5-git-send-email-eswierk@skyportsystems.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1468426776-42762-1-git-send-email-eswierk@skyportsystems.com> References: <1466557831-113440-1-git-send-email-eswierk@skyportsystems.com> <1468426776-42762-1-git-send-email-eswierk@skyportsystems.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some TPM chips report bogus command durations in their capabilities, just as others report incorrect timeouts. Rework tpm_get_timeouts() to allow chip drivers to override either via a single callback. Also clean up handling of TPMs that report milliseconds instead of microseconds. Signed-off-by: Ed Swierk --- drivers/char/tpm/tpm-interface.c | 148 ++++++++++++++++++++++----------------- drivers/char/tpm/tpm_tis_core.c | 32 +++------ include/linux/tpm.h | 3 +- 3 files changed, 94 insertions(+), 89 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index dc492ee..9dafc25 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -513,10 +513,10 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type) int tpm_get_timeouts(struct tpm_chip *chip) { - cap_t cap; - unsigned long new_timeout[4]; - unsigned long old_timeout[4]; - ssize_t rc; + cap_t cap1, cap2; + int rc; + unsigned long orig_timeout_a, orig_timeout_b, orig_timeout_c, + orig_timeout_d, orig_duration[3]; if (chip->flags & TPM_CHIP_FLAG_TPM2) { /* Fixed timeouts for TPM2 */ @@ -533,7 +533,7 @@ int tpm_get_timeouts(struct tpm_chip *chip) return 0; } - rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, + rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap1, "attempting to determine the timeouts"); if (rc == TPM_ERR_INVALID_POSTINIT) { /* The TPM is not started, we are the first to talk to it. @@ -542,77 +542,95 @@ int tpm_get_timeouts(struct tpm_chip *chip) if (tpm_startup(chip, TPM_ST_CLEAR)) return rc; - rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, + rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap1, "attempting to determine the timeouts"); } if (rc) return rc; - old_timeout[0] = be32_to_cpu(cap.timeout.a); - old_timeout[1] = be32_to_cpu(cap.timeout.b); - old_timeout[2] = be32_to_cpu(cap.timeout.c); - old_timeout[3] = be32_to_cpu(cap.timeout.d); - memcpy(new_timeout, old_timeout, sizeof(new_timeout)); - - /* - * Provide ability for vendor overrides of timeout values in case - * of misreporting. - */ - if (chip->ops->update_timeouts != NULL) - chip->timeout_adjusted = - chip->ops->update_timeouts(chip, new_timeout); - - if (!chip->timeout_adjusted) { - /* Don't overwrite default if value is 0 */ - if (new_timeout[0] != 0 && new_timeout[0] < 1000) { - int i; - - /* timeouts in msec rather usec */ - for (i = 0; i != ARRAY_SIZE(new_timeout); i++) - new_timeout[i] *= 1000; - chip->timeout_adjusted = true; - } - } - - /* Report adjusted timeouts */ - if (chip->timeout_adjusted) { - dev_info(&chip->dev, - HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n", - old_timeout[0], new_timeout[0], - old_timeout[1], new_timeout[1], - old_timeout[2], new_timeout[2], - old_timeout[3], new_timeout[3]); - } - - chip->timeout_a = usecs_to_jiffies(new_timeout[0]); - chip->timeout_b = usecs_to_jiffies(new_timeout[1]); - chip->timeout_c = usecs_to_jiffies(new_timeout[2]); - chip->timeout_d = usecs_to_jiffies(new_timeout[3]); - - rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap, + rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap2, "attempting to determine the durations"); if (rc) return rc; - chip->duration[TPM_SHORT] = - usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short)); - chip->duration[TPM_MEDIUM] = - usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium)); - chip->duration[TPM_LONG] = - usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long)); + be32_to_cpus(&cap1.timeout.a); + be32_to_cpus(&cap1.timeout.b); + be32_to_cpus(&cap1.timeout.c); + be32_to_cpus(&cap1.timeout.d); + chip->timeout_a = usecs_to_jiffies(cap1.timeout.a); + chip->timeout_b = usecs_to_jiffies(cap1.timeout.b); + chip->timeout_c = usecs_to_jiffies(cap1.timeout.c); + chip->timeout_d = usecs_to_jiffies(cap1.timeout.d); - /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above - * value wrong and apparently reports msecs rather than usecs. So we - * fix up the resulting too-small TPM_SHORT value to make things work. - * We also scale the TPM_MEDIUM and -_LONG values by 1000. - */ - if (chip->duration[TPM_SHORT] < (HZ / 100)) { - chip->duration[TPM_SHORT] = HZ; - chip->duration[TPM_MEDIUM] *= 1000; - chip->duration[TPM_LONG] *= 1000; - chip->duration_adjusted = true; - dev_info(&chip->dev, "Adjusting TPM timeout parameters."); + /* Some TPMs report timeouts in milliseconds rather than + microseconds. Use a value between 1 and 1000 as an + indication that this is the case. */ + if (cap1.timeout.a > 0 && cap1.timeout.a < 1000) { + chip->timeout_a = msecs_to_jiffies(cap1.timeout.a); + chip->timeout_b = msecs_to_jiffies(cap1.timeout.b); + chip->timeout_c = msecs_to_jiffies(cap1.timeout.c); + chip->timeout_d = msecs_to_jiffies(cap1.timeout.d); + chip->timeout_adjusted = true; } + + be32_to_cpus(&cap2.duration.tpm_short); + be32_to_cpus(&cap2.duration.tpm_medium); + be32_to_cpus(&cap2.duration.tpm_long); + chip->duration[TPM_SHORT] = + usecs_to_jiffies(cap2.duration.tpm_short); + chip->duration[TPM_MEDIUM] = + usecs_to_jiffies(cap2.duration.tpm_medium); + chip->duration[TPM_LONG] = + usecs_to_jiffies(cap2.duration.tpm_long); + + orig_timeout_a = chip->timeout_a; + orig_timeout_b = chip->timeout_b; + orig_timeout_c = chip->timeout_c; + orig_timeout_d = chip->timeout_d; + memcpy(orig_duration, chip->duration, 3 * sizeof(unsigned long)); + + /* Interpret duration values between 1 and 10000 as + milliseconds to deal with TPMs like the Broadcom BCM0102 in + the Dell Latitude D820. */ + if (cap2.duration.tpm_short > 0 && cap2.duration.tpm_short < 10000) { + chip->duration[TPM_SHORT] = + msecs_to_jiffies(cap2.duration.tpm_short); + chip->duration[TPM_MEDIUM] = + msecs_to_jiffies(cap2.duration.tpm_medium); + chip->duration[TPM_LONG] = + msecs_to_jiffies(cap2.duration.tpm_long); + chip->duration_adjusted = true; + } + + if (chip->ops->update_timeouts != NULL) + chip->ops->update_timeouts(chip); + + if (chip->timeout_adjusted) { + dev_info(&chip->dev, + HW_ERR "Adjusted timeouts: A %u->%uus B %u->%uus" + " C %u->%uus D %u->%uus\n", + jiffies_to_usecs(orig_timeout_a), + jiffies_to_usecs(chip->timeout_a), + jiffies_to_usecs(orig_timeout_b), + jiffies_to_usecs(chip->timeout_b), + jiffies_to_usecs(orig_timeout_c), + jiffies_to_usecs(chip->timeout_c), + jiffies_to_usecs(orig_timeout_d), + jiffies_to_usecs(chip->timeout_d)); + } + + if (chip->duration_adjusted) { + dev_info(&chip->dev, + HW_ERR "Adjusted durations: short %u->%uus" + " medium %u->%uus long %u->%uus\n", + jiffies_to_usecs(orig_duration[TPM_SHORT]), + jiffies_to_usecs(chip->duration[TPM_SHORT]), + jiffies_to_usecs(orig_duration[TPM_MEDIUM]), + jiffies_to_usecs(chip->duration[TPM_MEDIUM]), + jiffies_to_usecs(orig_duration[TPM_LONG]), + jiffies_to_usecs(chip->duration[TPM_LONG])); + } + return 0; } EXPORT_SYMBOL_GPL(tpm_get_timeouts); diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index e62fdeb..f013664 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -398,37 +398,25 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len) return rc; } -struct tis_vendor_timeout_override { - u32 did_vid; - unsigned long timeout_us[4]; -}; - -static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = { - /* Atmel 3204 */ - { 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000), - (TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } }, -}; - -static bool tpm_tis_update_timeouts(struct tpm_chip *chip, - unsigned long *timeout_cap) +static void tpm_tis_update_timeouts(struct tpm_chip *chip) { struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); - int i, rc; + int rc; u32 did_vid; rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid); if (rc < 0) return rc; - for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) { - if (vendor_timeout_overrides[i].did_vid != did_vid) - continue; - memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us, - sizeof(vendor_timeout_overrides[i].timeout_us)); - return true; + switch (did_vid) { + case 0x32041114: /* Atmel 3204 */ + chip->timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT); + chip->timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT); + chip->timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT); + chip->timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT); + chip->timeout_adjusted = true; + break; } - - return false; } /* diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 706e63e..2380ebf 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -41,8 +41,7 @@ struct tpm_class_ops { int (*send) (struct tpm_chip *chip, u8 *buf, size_t len); void (*cancel) (struct tpm_chip *chip); u8 (*status) (struct tpm_chip *chip); - bool (*update_timeouts)(struct tpm_chip *chip, - unsigned long *timeout_cap); + void (*update_timeouts)(struct tpm_chip *chip); }; -- 1.9.1