[PATCH v2 5/7] tpm: TPM 2.0 sysfs attributes
From: Jarkko Sakkinen
Date: Tue Oct 07 2014 - 13:02:44 EST
Implemented sysfs attributes for TPM2 devices.
Documentation/ABI/stable/sysfs-class/tpm2 contains descriptions
of these attributes.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
---
Documentation/ABI/stable/sysfs-class-tpm2 | 69 +++++++
drivers/char/tpm/Makefile | 2 +-
drivers/char/tpm/tpm-chip.c | 10 +-
drivers/char/tpm/tpm.h | 24 +++
drivers/char/tpm/tpm2-sysfs.c | 314 ++++++++++++++++++++++++++++++
5 files changed, 416 insertions(+), 3 deletions(-)
create mode 100644 Documentation/ABI/stable/sysfs-class-tpm2
create mode 100644 drivers/char/tpm/tpm2-sysfs.c
diff --git a/Documentation/ABI/stable/sysfs-class-tpm2 b/Documentation/ABI/stable/sysfs-class-tpm2
new file mode 100644
index 0000000..e9d4b6a
--- /dev/null
+++ b/Documentation/ABI/stable/sysfs-class-tpm2
@@ -0,0 +1,69 @@
+What: /sys/class/misc/tpmX/device/
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The device/ directory under a specific TPM instance exposes
+ the properties of that TPM chip.
+
+What: /sys/class/misc/tpmX/device/version
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The "version" property prints the protocol version number
+ in the major.minor format.
+
+What: /sys/class/misc/tpmX/device/enabled_sh
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The "enabled_sh" property prints a '1' if the Storage Hierarchy
+ is enabled.
+
+What: /sys/class/misc/tpmX/device/enabled_eh
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The "enabled_eh" property prints a '1' if the Endorsement Hierarchy
+ is enabled.
+
+What: /sys/class/misc/tpmX/device/owned_sh
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The "owned_sh" property prints a '1' if the ownership of the
+ Storage Hierarchy has been taken.
+
+What: /sys/class/misc/tpmX/device/owned_eh
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The "owned_sh" property prints a '1' if the ownership of the
+ Endrosoment Hierarchy has been taken.
+
+What: /sys/class/misc/tpmX/device/manufacturer
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The "manufacturer" property prints the vendor ID of the TPM
+ manufacturer.
+
+What: /sys/class/misc/tpmX/device/firmware
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The property prints the vendor-specific value indicating the
+ version of the firmware.
+
+What: /sys/class/misc/tpmX/device/pcr/sha1/X
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: These files print PCR values for the SHA-1 bank.
+
+What: /sys/class/misc/tpmX/device/cancel
+Date: October 2014
+KernelVersion: 3.19
+Contact: tpmdd-devel@xxxxxxxxxxxx
+Description: The "cancel" property allows you to cancel the currently
+ pending TPM command. Writing any value to cancel will call the
+ TPM chip specific cancel operation.
diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index ae56af9..d3cf905 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -2,7 +2,7 @@
# Makefile for the kernel tpm device drivers.
#
obj-$(CONFIG_TCG_TPM) += tpm.o
-tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o
+tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o tpm2-sysfs.o
tpm-$(CONFIG_ACPI) += tpm_ppi.o
ifdef CONFIG_ACPI
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 6cc4cee..5c50fd7 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -130,7 +130,10 @@ int tpm_chip_register(struct tpm_chip *chip)
if (rc)
return rc;
- rc = tpm_sysfs_add_device(chip);
+ if (chip->flags & TPM_CHIP_FLAG_TPM2)
+ rc = tpm2_sysfs_add_device(chip->dev);
+ else
+ rc = tpm_sysfs_add_device(chip);
if (rc)
goto del_misc;
@@ -171,7 +174,10 @@ void tpm_chip_unregister(struct tpm_chip *chip)
synchronize_rcu();
tpm_dev_del_device(chip);
- tpm_sysfs_del_device(chip);
+ if (chip->flags & TPM_CHIP_FLAG_TPM2)
+ tpm2_sysfs_del_device(chip->dev);
+ else
+ tpm_sysfs_del_device(chip);
tpm_remove_ppi(&chip->dev->kobj);
tpm_bios_log_teardown(chip->bios_dir);
}
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index d141639..4678cdf 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -107,6 +107,24 @@ enum tpm2_capabilities {
TPM2_CAP_TPM_PROPERTIES = 6,
};
+enum tpm2_tpm_properties {
+ TPM2_PT_MANUFACTURER = 0x00000105,
+ TPM2_PT_FIRMWARE_VERSION_1 = 0x00000111,
+ TPM2_PT_FIRMWARE_VERSION_2 = 0x00000111,
+ TPM2_PT_PERMANENT = 0x00000200,
+ TPM2_PT_STARTUP_CLEAR = 0x00000201,
+};
+
+enum tpm2_pt_startup_clear {
+ TPM2_PT_SC_SH_ENABLE = BIT(1),
+ TPM2_PT_SC_EH_ENABLE = BIT(2),
+};
+
+enum tpm2_pt_permanent {
+ TPM2_PT_PM_OWNER_AUTH_SET = BIT(0),
+ TPM2_PT_PM_ENDORSEMENT_AUTH_SET = BIT(1),
+};
+
enum tpm2_startup_types {
TPM2_SU_CLEAR = 0x0000,
TPM2_SU_STATE = 0x0001,
@@ -165,6 +183,9 @@ struct tpm_chip {
struct dentry **bios_dir;
+ struct kobject *pcrs_kobj;
+ void *sha1_bank;
+
struct list_head list;
};
@@ -419,3 +440,6 @@ extern ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
u32* value, const char *desc);
extern unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *, u32);
extern int tpm2_do_selftest(struct tpm_chip *chip);
+
+int tpm2_sysfs_add_device(struct device *dev);
+void tpm2_sysfs_del_device(struct device *dev);
diff --git a/drivers/char/tpm/tpm2-sysfs.c b/drivers/char/tpm/tpm2-sysfs.c
new file mode 100644
index 0000000..e6e603e
--- /dev/null
+++ b/drivers/char/tpm/tpm2-sysfs.c
@@ -0,0 +1,314 @@
+/*
+ * Copyright (C) 2014 Intel Corporation
+ * Copyright (C) 2004 IBM Corporation
+ * Copyright (C) 2013 Obsidian Research Corp
+ *
+ * Authors:
+ * Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
+ *
+ * sysfs filesystem inspection interface to the TPM
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ */
+#include <linux/device.h>
+#include <linux/slab.h>
+#include "tpm.h"
+
+static ssize_t enabled_sh_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ u32 value;
+ ssize_t rc;
+
+ rc = tpm2_get_tpm_pt(chip, TPM2_PT_STARTUP_CLEAR, &value,
+ "could not retrieve STARTUP_CLEAR property");
+ if (rc)
+ return 0;
+
+ rc = sprintf(buf, "%d\n", (value & TPM2_PT_SC_SH_ENABLE) > 0);
+ return rc;
+}
+static DEVICE_ATTR_RO(enabled_sh);
+
+static ssize_t enabled_eh_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ u32 value;
+ ssize_t rc;
+
+ rc = tpm2_get_tpm_pt(chip, TPM2_PT_STARTUP_CLEAR, &value,
+ "could not retrieve STARTUP_CLEAR property");
+ if (rc)
+ return 0;
+
+ rc = sprintf(buf, "%d\n", (value & TPM2_PT_SC_EH_ENABLE) > 0);
+ return rc;
+}
+static DEVICE_ATTR_RO(enabled_eh);
+
+static ssize_t owned_sh_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ u32 value;
+ ssize_t rc;
+
+ rc = tpm2_get_tpm_pt(chip, TPM2_PT_PERMANENT, &value,
+ "could not retrieve PERMANENT property");
+ if (rc)
+ return 0;
+
+ rc = sprintf(buf, "%d\n", (value & TPM2_PT_PM_OWNER_AUTH_SET) > 0);
+ return rc;
+}
+static DEVICE_ATTR_RO(owned_sh);
+
+static ssize_t owned_eh_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ u32 value;
+ ssize_t rc;
+
+ rc = tpm2_get_tpm_pt(chip, TPM2_PT_PERMANENT, &value,
+ "could not retrieve PERMANENT property");
+ if (rc)
+ return 0;
+
+ rc = sprintf(buf, "%d\n", (value & TPM2_PT_PM_ENDORSEMENT_AUTH_SET) > 0);
+ return rc;
+}
+static DEVICE_ATTR_RO(owned_eh);
+
+static ssize_t manufacturer_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ u32 manufacturer;
+ ssize_t rc;
+ char *str = buf;
+
+ rc = tpm2_get_tpm_pt(chip, TPM2_PT_MANUFACTURER, (u32 *) &manufacturer,
+ "could not retrieve MANUFACTURER property");
+ if (rc)
+ return 0;
+
+ str += sprintf(str, "0x%08x\n", be32_to_cpu(manufacturer));
+
+ return str - buf;
+}
+static DEVICE_ATTR_RO(manufacturer);
+
+static ssize_t firmware_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ u32 firmware1;
+ u32 firmware2;
+ ssize_t rc;
+ char *str = buf;
+
+ rc = tpm2_get_tpm_pt(chip, TPM2_PT_FIRMWARE_VERSION_1, (u32 *) &firmware1,
+ "could not retrieve FIRMWARE_VERSION_1 property");
+ if (rc)
+ return 0;
+
+ rc = tpm2_get_tpm_pt(chip, TPM2_PT_FIRMWARE_VERSION_2, (u32 *) &firmware2,
+ "could not retrieve FIRMWARE_VERSION_2 property");
+ if (rc)
+ return 0;
+
+ str += sprintf(str, "0x%08x.0x%08x\n", firmware1, firmware2);
+
+ return str - buf;
+}
+static DEVICE_ATTR_RO(firmware);
+
+static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ if (chip == NULL)
+ return 0;
+
+ chip->ops->cancel(chip);
+ return count;
+}
+static DEVICE_ATTR_WO(cancel);
+
+static ssize_t version_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ char *str = buf;
+
+ str += sprintf(str, "2.0\n");
+
+ return str - buf;
+}
+static DEVICE_ATTR_RO(version);
+
+static struct attribute *tpm_dev_attrs[] = {
+ &dev_attr_enabled_sh.attr,
+ &dev_attr_enabled_eh.attr,
+ &dev_attr_owned_sh.attr,
+ &dev_attr_owned_eh.attr,
+ &dev_attr_manufacturer.attr,
+ &dev_attr_firmware.attr,
+ &dev_attr_cancel.attr,
+ &dev_attr_version.attr,
+ NULL,
+};
+
+static const struct attribute_group tpm_dev_group = {
+ .attrs = tpm_dev_attrs,
+};
+
+struct pcr_attr {
+ struct attribute attr;
+ unsigned int index;
+ char name[3];
+};
+
+struct pcr_bank {
+ struct kobject kobj;
+ struct kobj_type ktype;
+ struct device *dev;
+ struct pcr_attr pcr_attrs[TPM2_PLATFORM_PCR];
+ struct attribute *attrs[TPM2_PLATFORM_PCR + 1];
+};
+
+static ssize_t pcr_bank_attr_show(struct kobject *kobj,
+ struct attribute *attr,
+ char *buf)
+{
+ u8 digest[TPM_DIGEST_SIZE];
+ ssize_t rc;
+ int i;
+ char *str = buf;
+ struct tpm_chip *chip;
+ struct pcr_attr *pcr_attr;
+ struct pcr_bank *pcr_bank;
+
+ pcr_attr = container_of(attr, struct pcr_attr, attr);
+ pcr_bank = container_of(kobj, struct pcr_bank, kobj);
+ chip = dev_get_drvdata(pcr_bank->dev);
+
+ rc = tpm2_pcr_read(chip, pcr_attr->index, digest);
+ if (rc)
+ return rc;
+
+ for (i = 0; i < TPM_DIGEST_SIZE; i++)
+ str += sprintf(str, "%02X", digest[i]);
+
+ str += sprintf(str, "\n");
+
+ return str - buf;
+}
+
+static void pcr_bank_release(struct kobject *kobj)
+{
+ struct pcr_bank *pcr_bank;
+ pcr_bank = container_of(kobj, struct pcr_bank, kobj);
+ kfree(pcr_bank);
+}
+
+static const struct sysfs_ops pcr_bank_sysfs_ops = {
+ .show = pcr_bank_attr_show,
+};
+
+static struct pcr_bank *pcr_bank_create(struct device *dev,
+ struct kobject *parent_kobj)
+{
+ struct pcr_bank *pcr_bank;
+ struct pcr_attr *pcr_attr;
+ struct attribute *attr;
+ int i;
+ int rc;
+
+ pcr_bank = kzalloc(sizeof(*pcr_bank), GFP_KERNEL);
+ if (!pcr_bank)
+ return NULL;
+
+ pcr_bank->dev = dev;
+ pcr_bank->ktype.sysfs_ops = &pcr_bank_sysfs_ops;
+ pcr_bank->ktype.default_attrs = pcr_bank->attrs;
+ pcr_bank->ktype.release = pcr_bank_release;
+
+ for (i = 0; i < TPM2_PLATFORM_PCR; i++) {
+ pcr_attr = &pcr_bank->pcr_attrs[i];
+ pcr_attr->index = i;
+ sprintf(pcr_attr->name, "%d", i);
+
+ attr = &pcr_attr->attr;
+ attr->name = pcr_attr->name;
+ attr->mode = S_IRUGO;
+
+ pcr_bank->attrs[i] = attr;
+ }
+
+ pcr_bank->attrs[i] = NULL;
+
+ rc = kobject_init_and_add(&pcr_bank->kobj, &pcr_bank->ktype,
+ parent_kobj, "sha1");
+ if (rc) {
+ kfree(pcr_bank);
+ return NULL;
+ }
+
+ return pcr_bank;
+}
+
+int tpm2_sysfs_add_device(struct device *dev)
+{
+ struct tpm_chip *chip;
+ struct pcr_bank *pcr_bank;
+ struct kobject *pcrs_kobj;
+ int rc;
+
+ rc = sysfs_create_group(&dev->kobj, &tpm_dev_group);
+ if (rc) {
+ dev_err(dev, "failed to create sysfs attributes, %d\n", rc);
+ return rc;
+ }
+
+ pcrs_kobj = kobject_create_and_add("pcrs", &dev->kobj);
+ if (!pcrs_kobj) {
+ sysfs_remove_group(&dev->kobj, &tpm_dev_group);
+ dev_err(dev, "failed to create sysfs attributes, %d\n", rc);
+ return -ENOMEM;
+ }
+
+ pcr_bank = pcr_bank_create(dev, pcrs_kobj);
+ if (!pcr_bank) {
+ kobject_put(pcrs_kobj);
+ sysfs_remove_group(&dev->kobj, &tpm_dev_group);
+ dev_err(dev, "failed to create sysfs attributes, %d\n", rc);
+ return -ENOMEM;
+ }
+
+ kobject_uevent(pcrs_kobj, KOBJ_ADD);
+
+ chip = dev_get_drvdata(dev);
+ chip->pcrs_kobj = pcrs_kobj;
+ chip->sha1_bank = &pcr_bank->kobj;
+
+ return 0;
+}
+
+void tpm2_sysfs_del_device(struct device *dev)
+{
+ struct tpm_chip *chip;
+
+ chip = dev_get_drvdata(dev);
+
+ kobject_put(chip->sha1_bank);
+ kobject_put(chip->pcrs_kobj);
+ sysfs_remove_group(&dev->kobj, &tpm_dev_group);
+}
--
2.1.0
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