From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1424240AbcFHXAy (ORCPT ); Wed, 8 Jun 2016 19:00:54 -0400 Received: from mail-pf0-f179.google.com ([209.85.192.179]:36754 "EHLO mail-pf0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161950AbcFHXAd (ORCPT ); Wed, 8 Jun 2016 19:00:33 -0400 From: Ed Swierk To: tpmdd-devel@lists.sourceforge.net Cc: eswierk@skyportsystems.com, stefanb@us.ibm.com, jarkko.sakkinen@linux.intel.com, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, jgunthorpe@obsidianresearch.com Subject: [PATCH v5 3/4] tpm: Allow TPM chip drivers to override reported command durations Date: Wed, 8 Jun 2016 16:00:17 -0700 Message-Id: <1465426818-89356-4-git-send-email-eswierk@skyportsystems.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1465426818-89356-1-git-send-email-eswierk@skyportsystems.com> References: <1465346740-60120-1-git-send-email-eswierk@skyportsystems.com> <1465426818-89356-1-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 | 177 +++++++++++++++++++++------------------ drivers/char/tpm/tpm_tis.c | 35 ++------ include/linux/tpm.h | 3 +- 3 files changed, 106 insertions(+), 109 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index cc1e5bc..b8a08bb 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -502,123 +502,138 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type) "attempting to start the TPM"); } -int tpm_get_timeouts(struct tpm_chip *chip) +static int tpm_get_cap_prop(struct tpm_chip *chip, __be32 type, int size, + cap_t *cap, char *desc) { struct tpm_cmd_t tpm_cmd; - unsigned long new_timeout[4]; - unsigned long old_timeout[4]; - struct duration_t *duration_cap; ssize_t rc; tpm_cmd.header.in = tpm_getcap_header; tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); - tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT; + tpm_cmd.params.getcap_in.subcap = type; rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL); if (rc == TPM_ERR_INVALID_POSTINIT) { /* The TPM is not started, we are the first to talk to it. Execute a startup command. */ - dev_info(chip->pdev, "Issuing TPM_STARTUP"); + dev_info(chip->pdev, "Issuing TPM_STARTUP\n"); if (tpm_startup(chip, TPM_ST_CLEAR)) return rc; tpm_cmd.header.in = tpm_getcap_header; tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); - tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT; + tpm_cmd.params.getcap_in.subcap = type; rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL); } + if (rc) { dev_err(chip->pdev, - "A TPM error (%zd) occurred attempting to determine the timeouts\n", - rc); - goto duration; + "Error %zd reading %s\n", rc, desc); + return -EINVAL; } if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 || be32_to_cpu(tpm_cmd.header.out.length) - != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32)) + != sizeof(tpm_cmd.header.out) + sizeof(u32) + size * sizeof(u32)) { + dev_err(chip->pdev, + "Bad return code or length reading %s\n", desc); return -EINVAL; - - old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a); - old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b); - old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c); - old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.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->vendor.timeout_adjusted = - chip->ops->update_timeouts(chip, new_timeout); - - if (!chip->vendor.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->vendor.timeout_adjusted = true; - } } - /* Report adjusted timeouts */ - if (chip->vendor.timeout_adjusted) { - dev_info(chip->pdev, - 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]); - } + memcpy(cap, &tpm_cmd.params.getcap_out.cap, sizeof(cap_t)); - chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]); - chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]); - chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]); - chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]); + return 0; +} -duration: - tpm_cmd.header.in = tpm_getcap_header; - tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; - tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); - tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION; +int tpm_get_timeouts(struct tpm_chip *chip) +{ + cap_t cap1, cap2; + int rc1, rc2; + struct tpm_vendor_specific orig_vendor; + + rc1 = tpm_get_cap_prop(chip, TPM_CAP_PROP_TIS_TIMEOUT, 4, &cap1, + "timeouts"); + if (rc1 == 0) { + 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->vendor.timeout_a = usecs_to_jiffies(cap1.timeout.a); + chip->vendor.timeout_b = usecs_to_jiffies(cap1.timeout.b); + chip->vendor.timeout_c = usecs_to_jiffies(cap1.timeout.c); + chip->vendor.timeout_d = usecs_to_jiffies(cap1.timeout.d); + } + rc2 = tpm_get_cap_prop(chip, TPM_CAP_PROP_TIS_DURATION, 3, &cap2, + "durations"); + if (rc2 == 0) { + be32_to_cpus(&cap2.duration.tpm_short); + be32_to_cpus(&cap2.duration.tpm_medium); + be32_to_cpus(&cap2.duration.tpm_long); + chip->vendor.duration[TPM_SHORT] = + usecs_to_jiffies(cap2.duration.tpm_short); + chip->vendor.duration[TPM_MEDIUM] = + usecs_to_jiffies(cap2.duration.tpm_medium); + chip->vendor.duration[TPM_LONG] = + usecs_to_jiffies(cap2.duration.tpm_long); + } - rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, - "attempting to determine the durations"); - if (rc) - return rc; + memcpy(&orig_vendor, &chip->vendor, sizeof(orig_vendor)); + + /* 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 (rc1 == 0 && cap1.timeout.a > 0 && cap1.timeout.a < 1000) { + chip->vendor.timeout_a = msecs_to_jiffies(cap1.timeout.a); + chip->vendor.timeout_b = msecs_to_jiffies(cap1.timeout.b); + chip->vendor.timeout_c = msecs_to_jiffies(cap1.timeout.c); + chip->vendor.timeout_d = msecs_to_jiffies(cap1.timeout.d); + chip->vendor.timeout_adjusted = true; + } + /* Interpret duration values between 1 and 10000 as + milliseconds to deal with TPMs like the Broadcom BCM0102 in + the Dell Latitude D820. */ + if (rc2 == 0 && cap2.duration.tpm_short > 0 && + cap2.duration.tpm_short < 10000) { + chip->vendor.duration[TPM_SHORT] = + msecs_to_jiffies(cap2.duration.tpm_short); + chip->vendor.duration[TPM_MEDIUM] = + msecs_to_jiffies(cap2.duration.tpm_medium); + chip->vendor.duration[TPM_LONG] = + msecs_to_jiffies(cap2.duration.tpm_long); + chip->vendor.duration_adjusted = true; + } - if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 || - be32_to_cpu(tpm_cmd.header.out.length) - != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32)) - return -EINVAL; + if (chip->ops->update_timeouts != NULL) + chip->ops->update_timeouts(chip); - duration_cap = &tpm_cmd.params.getcap_out.cap.duration; - chip->vendor.duration[TPM_SHORT] = - usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short)); - chip->vendor.duration[TPM_MEDIUM] = - usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium)); - chip->vendor.duration[TPM_LONG] = - usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long)); - - /* 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->vendor.duration[TPM_SHORT] < (HZ / 100)) { - chip->vendor.duration[TPM_SHORT] = HZ; - chip->vendor.duration[TPM_MEDIUM] *= 1000; - chip->vendor.duration[TPM_LONG] *= 1000; - chip->vendor.duration_adjusted = true; - dev_info(chip->pdev, "Adjusting TPM timeout parameters."); + if (chip->vendor.timeout_adjusted) { + dev_info(chip->pdev, + HW_ERR "Adjusted timeouts: A %u->%uus B %u->%uus" + " C %u->%uus D %u->%uus\n", + jiffies_to_usecs(orig_vendor.timeout_a), + jiffies_to_usecs(chip->vendor.timeout_a), + jiffies_to_usecs(orig_vendor.timeout_b), + jiffies_to_usecs(chip->vendor.timeout_b), + jiffies_to_usecs(orig_vendor.timeout_c), + jiffies_to_usecs(chip->vendor.timeout_c), + jiffies_to_usecs(orig_vendor.timeout_d), + jiffies_to_usecs(chip->vendor.timeout_d)); + } + if (chip->vendor.duration_adjusted) { + dev_info(chip->pdev, + HW_ERR "Adjusted durations: short %u->%uus" + " medium %u->%uus long %u->%uus\n", + jiffies_to_usecs(orig_vendor.duration[TPM_SHORT]), + jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]), + jiffies_to_usecs(orig_vendor.duration[TPM_MEDIUM]), + jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]), + jiffies_to_usecs(orig_vendor.duration[TPM_LONG]), + jiffies_to_usecs(chip->vendor.duration[TPM_LONG])); } + return 0; } EXPORT_SYMBOL_GPL(tpm_get_timeouts); diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c index 088fa86..caf7278 100644 --- a/drivers/char/tpm/tpm_tis.c +++ b/drivers/char/tpm/tpm_tis.c @@ -475,34 +475,17 @@ 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) { - int i; - u32 did_vid; - - did_vid = ioread32(chip->vendor.iobase + TPM_DID_VID(0)); - - 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 (ioread32(chip->vendor.iobase + TPM_DID_VID(0))) { + case 0x32041114: /* Atmel 3204 */ + chip->vendor.timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT); + chip->vendor.timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT); + chip->vendor.timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT); + chip->vendor.timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT); + chip->vendor.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