[PATCH v10 0/5] Multi-instance vTPM proxy driver

[PATCH v10 0/5] Multi-instance vTPM proxy driver

[Stefan Berger]

The following series of patches implements a multi-instance vTPM 
proxy driver that can dynamically create TPM 'server' and client device
pairs.

Using an ioctl on the provided /dev/vtpmx, a client-side vTPM device
and a server side file descriptor is created. The file descriptor must
be passed to a TPM emulator. The device driver will initialize the
emulated TPM using TPM 1.2 or TPM 2 startup commands and it will read
the command durations from the device in case of a TPM 1.2. The choice
of emulated TPM device (1.2 or 2) must be provided with a flag in
the ioctl.

The patches are based on the tip of a recent checkout of Jarkko's tree
(master branch).

   Stefan

v9->v10:
 - add new patch 1 with sysfs related rework; reworked patch 2 as a consequence
 - patch 3: fixed ioctl from using _IOW to using _IOWR (reinstall headers
   and rebuild test tools)
 - patch 3: do not use priv field anymore but uses dev_set_drvdata /
   dev_get_drvdata instead now

v8->v9:
 - move constant from public header into tpm_vtpm_proxy.c
 - Replaced VTPM_PROXY_MAGIC in ioctl definition with its value (0xa1)
 - Check for the STATE_OPEN_FLAG in wait_event_interruptable and after
   returning from it

v7->v8:
 - minor tweaks on the documentation
 - Reordered function calls in the VTPM proxy driver's server side release
   function so that a client holding the 'ops' lock releases it before the
   driver tries to grab the lock when unregistering the device.

v6->v7:
 - Adjusted name of driver to tpm_vtpm_proxy from tpm_vtpm. Adjust function
   names, names of structures, and names of constants.
 - Adjusted IOCTL to use magic 0xa1 rather than the completely used 0xa0.
 - Extended driver documentation and added documentation of ioctl.
 - Moved test program to own project (dropped patch 11).

v5->v6:
 - Adapted errno's for unsupported flags and ioctls following Jason's
   comments

v4->v5:
 - Introduced different error codes for unsupported flags and ioctls
 - Added documentation patch




Jason Gunthorpe (1):
  tpm: Remove all uses of drvdata from the TPM Core

Stefan Berger (4):
  tpm: Introduce TPM_CHIP_FLAG_VIRTUAL
  tpm: Proxy driver for supporting multiple emulated TPMs
  tpm: Initialize TPM and get durations and timeouts
  tpm: Add documentation for the tpm_vtpm_proxy device driver

 Documentation/ioctl/ioctl-number.txt |   1 +
 Documentation/tpm/tpm_vtpm_proxy.txt |  71 ++++
 drivers/char/tpm/Kconfig             |  10 +
 drivers/char/tpm/Makefile            |   1 +
 drivers/char/tpm/tpm-chip.c          |  76 ++--
 drivers/char/tpm/tpm-interface.c     |   7 +-
 drivers/char/tpm/tpm-sysfs.c         |  61 ++--
 drivers/char/tpm/tpm.h               |  11 +-
 drivers/char/tpm/tpm_vtpm_proxy.c    | 650 +++++++++++++++++++++++++++++++++++
 include/uapi/linux/Kbuild            |   1 +
 include/uapi/linux/vtpm_proxy.h      |  36 ++
 11 files changed, 858 insertions(+), 67 deletions(-)
 create mode 100644 Documentation/tpm/tpm_vtpm_proxy.txt
 create mode 100644 drivers/char/tpm/tpm_vtpm_proxy.c
 create mode 100644 include/uapi/linux/vtpm_proxy.h

-- 
2.4.3


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[PATCH v10 2/5] tpm: Introduce TPM_CHIP_FLAG_VIRTUAL

[Stefan Berger]

Introduce TPM_CHIP_FLAG_VIRTUAL to be used when the chip device has no
parent device.

Prevent sysfs entries requiring a parent device from being created.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
---
 drivers/char/tpm/tpm-chip.c | 7 +++++--
 drivers/char/tpm/tpm.h      | 1 +
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 7e2c9cf..a12db8e 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -181,6 +181,9 @@ struct tpm_chip *tpm_chip_alloc(struct device *dev,
 	if (rc)
 		goto out;
 
+	if (!dev)
+		chip->flags |= TPM_CHIP_FLAG_VIRTUAL;
+
 	cdev_init(&chip->cdev, &tpm_fops);
 	chip->cdev.owner = THIS_MODULE;
 	chip->cdev.kobj.parent = &chip->dev.kobj;
@@ -297,7 +300,7 @@ static void tpm_del_legacy_sysfs(struct tpm_chip *chip)
 {
 	struct attribute **i;
 
-	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+	if (chip->flags & (TPM_CHIP_FLAG_TPM2 | TPM_CHIP_FLAG_VIRTUAL))
 		return;
 
 	sysfs_remove_link(&chip->dev.parent->kobj, "ppi");
@@ -315,7 +318,7 @@ static int tpm_add_legacy_sysfs(struct tpm_chip *chip)
 	struct attribute **i;
 	int rc;
 
-	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+	if (chip->flags & (TPM_CHIP_FLAG_TPM2 | TPM_CHIP_FLAG_VIRTUAL))
 		return 0;
 
 	rc = __compat_only_sysfs_link_entry_to_kobj(
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 508e8e0..ff4e53c 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -138,6 +138,7 @@ enum tpm_chip_flags {
 	TPM_CHIP_FLAG_REGISTERED	= BIT(0),
 	TPM_CHIP_FLAG_TPM2		= BIT(1),
 	TPM_CHIP_FLAG_IRQ		= BIT(2),
+	TPM_CHIP_FLAG_VIRTUAL		= BIT(3),
 };
 
 struct tpm_chip {
-- 
2.4.3

Re: [PATCH v10 2/5] tpm: Introduce TPM_CHIP_FLAG_VIRTUAL

[Jason Gunthorpe]

On Fri, Apr 15, 2016 at 09:50:13AM -0400, Stefan Berger wrote:
> Introduce TPM_CHIP_FLAG_VIRTUAL to be used when the chip device has no
> parent device.
> 
> Prevent sysfs entries requiring a parent device from being created.
> 
> Signed-off-by: Stefan Berger <stefanb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
>  drivers/char/tpm/tpm-chip.c | 7 +++++--
>  drivers/char/tpm/tpm.h      | 1 +
>  2 files changed, 6 insertions(+), 2 deletions(-)

Reviewed-by: Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>

Jason

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[PATCH v10 1/5] tpm: Remove all uses of drvdata from the TPM Core

[Stefan Berger]

From: Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>

The final thing preventing this was the way the sysfs files were
attached to the pdev. Follow the approach developed for ppi and move
the sysfs files to the chip->dev with symlinks from the pdev
for compatibility. Everything in the core now sanely uses container_of
to get the chip.

Signed-off-by: Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
Signed-off-by: Stefan Berger <stefanb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
---
 drivers/char/tpm/tpm-chip.c      | 73 ++++++++++++++++++++++++++++------------
 drivers/char/tpm/tpm-interface.c |  7 ++--
 drivers/char/tpm/tpm-sysfs.c     | 61 ++++++++++++++-------------------
 drivers/char/tpm/tpm.h           | 10 +++---
 4 files changed, 84 insertions(+), 67 deletions(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 5bc530c..7e2c9cf 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -170,9 +170,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *dev,
 	chip->dev.class = tpm_class;
 	chip->dev.release = tpm_dev_release;
 	chip->dev.parent = dev;
-#ifdef CONFIG_ACPI
 	chip->dev.groups = chip->groups;
-#endif
 
 	if (chip->dev_num == 0)
 		chip->dev.devt = MKDEV(MISC_MAJOR, TPM_MINOR);
@@ -276,14 +274,10 @@ static void tpm_del_char_device(struct tpm_chip *chip)
 
 static int tpm1_chip_register(struct tpm_chip *chip)
 {
-	int rc;
-
 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
 		return 0;
 
-	rc = tpm_sysfs_add_device(chip);
-	if (rc)
-		return rc;
+	tpm_sysfs_add_device(chip);
 
 	chip->bios_dir = tpm_bios_log_setup(dev_name(&chip->dev));
 
@@ -297,10 +291,50 @@ static void tpm1_chip_unregister(struct tpm_chip *chip)
 
 	if (chip->bios_dir)
 		tpm_bios_log_teardown(chip->bios_dir);
+}
+
+static void tpm_del_legacy_sysfs(struct tpm_chip *chip)
+{
+	struct attribute **i;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		return;
 
-	tpm_sysfs_del_device(chip);
+	sysfs_remove_link(&chip->dev.parent->kobj, "ppi");
+
+	for (i = chip->groups[0]->attrs; *i != NULL; ++i)
+		sysfs_remove_link(&chip->dev.parent->kobj, (*i)->name);
 }
 
+/* For compatibility with legacy sysfs paths we provide symlinks from the
+ * parent dev directory to selected names within the tpm chip directory. Old
+ * kernel versions created these files directly under the parent.
+ */
+static int tpm_add_legacy_sysfs(struct tpm_chip *chip)
+{
+	struct attribute **i;
+	int rc;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		return 0;
+
+	rc = __compat_only_sysfs_link_entry_to_kobj(
+		    &chip->dev.parent->kobj, &chip->dev.kobj, "ppi");
+	if (rc && rc != -ENOENT)
+		return rc;
+
+	/* All the names from tpm-sysfs */
+	for (i = chip->groups[0]->attrs; *i != NULL; ++i) {
+		rc = __compat_only_sysfs_link_entry_to_kobj(
+		    &chip->dev.parent->kobj, &chip->dev.kobj, (*i)->name);
+		if (rc) {
+			tpm_del_legacy_sysfs(chip);
+			return rc;
+		}
+	}
+
+	return 0;
+}
 /*
  * tpm_chip_register() - create a character device for the TPM chip
  * @chip: TPM chip to use.
@@ -323,24 +357,20 @@ int tpm_chip_register(struct tpm_chip *chip)
 	tpm_add_ppi(chip);
 
 	rc = tpm_add_char_device(chip);
-	if (rc)
-		goto out_err;
+	if (rc) {
+		tpm1_chip_unregister(chip);
+		return rc;
+	}
 
 	chip->flags |= TPM_CHIP_FLAG_REGISTERED;
 
-	if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
-		rc = __compat_only_sysfs_link_entry_to_kobj(
-		    &chip->dev.parent->kobj, &chip->dev.kobj, "ppi");
-		if (rc && rc != -ENOENT) {
-			tpm_chip_unregister(chip);
-			return rc;
-		}
+	rc = tpm_add_legacy_sysfs(chip);
+	if (rc) {
+		tpm_chip_unregister(chip);
+		return rc;
 	}
 
 	return 0;
-out_err:
-	tpm1_chip_unregister(chip);
-	return rc;
 }
 EXPORT_SYMBOL_GPL(tpm_chip_register);
 
@@ -362,8 +392,7 @@ void tpm_chip_unregister(struct tpm_chip *chip)
 	if (!(chip->flags & TPM_CHIP_FLAG_REGISTERED))
 		return;
 
-	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
-		sysfs_remove_link(&chip->dev.parent->kobj, "ppi");
+	tpm_del_legacy_sysfs(chip);
 
 	tpm1_chip_unregister(chip);
 	tpm_del_char_device(chip);
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 7cba092..080dade 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -432,12 +432,11 @@ static const struct tpm_input_header tpm_getcap_header = {
 	.ordinal = TPM_ORD_GET_CAP
 };
 
-ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
+ssize_t tpm_getcap(struct tpm_chip *chip, __be32 subcap_id, cap_t *cap,
 		   const char *desc)
 {
 	struct tpm_cmd_t tpm_cmd;
 	int rc;
-	struct tpm_chip *chip = dev_get_drvdata(dev);
 
 	tpm_cmd.header.in = tpm_getcap_header;
 	if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
@@ -935,7 +934,7 @@ static struct tpm_input_header savestate_header = {
  */
 int tpm_pm_suspend(struct device *dev)
 {
-	struct tpm_chip *chip = dev_get_drvdata(dev);
+	struct tpm_chip *chip = to_tpm_chip(dev);
 	struct tpm_cmd_t cmd;
 	int rc, try;
 
@@ -996,7 +995,7 @@ EXPORT_SYMBOL_GPL(tpm_pm_suspend);
  */
 int tpm_pm_resume(struct device *dev)
 {
-	struct tpm_chip *chip = dev_get_drvdata(dev);
+	struct tpm_chip *chip = to_tpm_chip(dev);
 
 	if (chip == NULL)
 		return -ENODEV;
diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index a7c3473..b46cf70 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -36,7 +36,7 @@ static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
 	int i, rc;
 	char *str = buf;
 
-	struct tpm_chip *chip = dev_get_drvdata(dev);
+	struct tpm_chip *chip = to_tpm_chip(dev);
 
 	tpm_cmd.header.in = tpm_readpubek_header;
 	err = tpm_transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
@@ -92,9 +92,9 @@ static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
 	ssize_t rc;
 	int i, j, num_pcrs;
 	char *str = buf;
-	struct tpm_chip *chip = dev_get_drvdata(dev);
+	struct tpm_chip *chip = to_tpm_chip(dev);
 
-	rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
+	rc = tpm_getcap(chip, TPM_CAP_PROP_PCR, &cap,
 			"attempting to determine the number of PCRS");
 	if (rc)
 		return 0;
@@ -119,8 +119,8 @@ static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
 	cap_t cap;
 	ssize_t rc;
 
-	rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
-			 "attempting to determine the permanent enabled state");
+	rc = tpm_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_PERM, &cap,
+			"attempting to determine the permanent enabled state");
 	if (rc)
 		return 0;
 
@@ -135,8 +135,8 @@ static ssize_t active_show(struct device *dev, struct device_attribute *attr,
 	cap_t cap;
 	ssize_t rc;
 
-	rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
-			 "attempting to determine the permanent active state");
+	rc = tpm_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_PERM, &cap,
+			"attempting to determine the permanent active state");
 	if (rc)
 		return 0;
 
@@ -151,8 +151,8 @@ static ssize_t owned_show(struct device *dev, struct device_attribute *attr,
 	cap_t cap;
 	ssize_t rc;
 
-	rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
-			 "attempting to determine the owner state");
+	rc = tpm_getcap(to_tpm_chip(dev), TPM_CAP_PROP_OWNER, &cap,
+			"attempting to determine the owner state");
 	if (rc)
 		return 0;
 
@@ -167,8 +167,8 @@ static ssize_t temp_deactivated_show(struct device *dev,
 	cap_t cap;
 	ssize_t rc;
 
-	rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
-			 "attempting to determine the temporary state");
+	rc = tpm_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_VOL, &cap,
+			"attempting to determine the temporary state");
 	if (rc)
 		return 0;
 
@@ -180,11 +180,12 @@ static DEVICE_ATTR_RO(temp_deactivated);
 static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
 			 char *buf)
 {
+	struct tpm_chip *chip = to_tpm_chip(dev);
 	cap_t cap;
 	ssize_t rc;
 	char *str = buf;
 
-	rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
+	rc = tpm_getcap(chip, TPM_CAP_PROP_MANUFACTURER, &cap,
 			"attempting to determine the manufacturer");
 	if (rc)
 		return 0;
@@ -192,8 +193,8 @@ static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
 		       be32_to_cpu(cap.manufacturer_id));
 
 	/* Try to get a TPM version 1.2 TPM_CAP_VERSION_INFO */
-	rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
-			 "attempting to determine the 1.2 version");
+	rc = tpm_getcap(chip, CAP_VERSION_1_2, &cap,
+			"attempting to determine the 1.2 version");
 	if (!rc) {
 		str += sprintf(str,
 			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
@@ -203,7 +204,7 @@ static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
 			       cap.tpm_version_1_2.revMinor);
 	} else {
 		/* Otherwise just use TPM_STRUCT_VER */
-		rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
+		rc = tpm_getcap(chip, CAP_VERSION_1_1, &cap,
 				"attempting to determine the 1.1 version");
 		if (rc)
 			return 0;
@@ -222,7 +223,7 @@ static DEVICE_ATTR_RO(caps);
 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);
+	struct tpm_chip *chip = to_tpm_chip(dev);
 	if (chip == NULL)
 		return 0;
 
@@ -234,7 +235,7 @@ static DEVICE_ATTR_WO(cancel);
 static ssize_t durations_show(struct device *dev, struct device_attribute *attr,
 			      char *buf)
 {
-	struct tpm_chip *chip = dev_get_drvdata(dev);
+	struct tpm_chip *chip = to_tpm_chip(dev);
 
 	if (chip->duration[TPM_LONG] == 0)
 		return 0;
@@ -251,7 +252,7 @@ static DEVICE_ATTR_RO(durations);
 static ssize_t timeouts_show(struct device *dev, struct device_attribute *attr,
 			     char *buf)
 {
-	struct tpm_chip *chip = dev_get_drvdata(dev);
+	struct tpm_chip *chip = to_tpm_chip(dev);
 
 	return sprintf(buf, "%d %d %d %d [%s]\n",
 		       jiffies_to_usecs(chip->timeout_a),
@@ -281,24 +282,12 @@ static const struct attribute_group tpm_dev_group = {
 	.attrs = tpm_dev_attrs,
 };
 
-int tpm_sysfs_add_device(struct tpm_chip *chip)
+void tpm_sysfs_add_device(struct tpm_chip *chip)
 {
-	int err;
-	err = sysfs_create_group(&chip->dev.parent->kobj,
-				 &tpm_dev_group);
-
-	if (err)
-		dev_err(&chip->dev,
-			"failed to create sysfs attributes, %d\n", err);
-	return err;
-}
-
-void tpm_sysfs_del_device(struct tpm_chip *chip)
-{
-	/* The sysfs routines rely on an implicit tpm_try_get_ops, this
-	 * function is called before ops is null'd and the sysfs core
-	 * synchronizes this removal so that no callbacks are running or can
-	 * run again
+	/* The sysfs routines rely on an implicit tpm_try_get_ops, device_del
+	 * is called before ops is null'd and the sysfs core synchronizes this
+	 * removal so that no callbacks are running or can run again
 	 */
-	sysfs_remove_group(&chip->dev.parent->kobj, &tpm_dev_group);
+	WARN_ON(chip->groups_cnt != 0);
+	chip->groups[chip->groups_cnt++] = &tpm_dev_group;
 }
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 8bc6fb8..508e8e0 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -168,9 +168,9 @@ struct tpm_chip {
 
 	struct dentry **bios_dir;
 
-#ifdef CONFIG_ACPI
-	const struct attribute_group *groups[2];
+	const struct attribute_group *groups[3];
 	unsigned int groups_cnt;
+#ifdef CONFIG_ACPI
 	acpi_handle acpi_dev_handle;
 	char ppi_version[TPM_PPI_VERSION_LEN + 1];
 #endif /* CONFIG_ACPI */
@@ -471,7 +471,8 @@ extern dev_t tpm_devt;
 extern const struct file_operations tpm_fops;
 extern struct idr dev_nums_idr;
 
-ssize_t	tpm_getcap(struct device *, __be32, cap_t *, const char *);
+ssize_t tpm_getcap(struct tpm_chip *chip, __be32 subcap_id, cap_t *cap,
+		   const char *desc);
 ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 		     size_t bufsiz);
 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, void *cmd, int len,
@@ -496,8 +497,7 @@ extern struct tpm_chip *tpmm_chip_alloc(struct device *pdev,
 extern int tpm_chip_register(struct tpm_chip *chip);
 extern void tpm_chip_unregister(struct tpm_chip *chip);
 
-int tpm_sysfs_add_device(struct tpm_chip *chip);
-void tpm_sysfs_del_device(struct tpm_chip *chip);
+void tpm_sysfs_add_device(struct tpm_chip *chip);
 
 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf);
 
-- 
2.4.3


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your business applications. It resolves application problems quickly and
reduces your MTTR. Get your free trial!
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[PATCH v10 3/5] tpm: Proxy driver for supporting multiple emulated TPMs

[Stefan Berger]

This patch implements a proxy driver for supporting multiple emulated TPMs
in a system.

The driver implements a device /dev/vtpmx that is used to created
a client device pair /dev/tpmX (e.g., /dev/tpm10) and a server side that
is accessed using a file descriptor returned by an ioctl.
The device /dev/tpmX is the usual TPM device created by the core TPM
driver. Applications or kernel subsystems can send TPM commands to it
and the corresponding server-side file descriptor receives these
commands and delivers them to an emulated TPM.

Signed-off-by: Stefan Berger <stefanb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>

CC: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
CC: linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
CC: linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
---
 drivers/char/tpm/Kconfig          |  10 +
 drivers/char/tpm/Makefile         |   1 +
 drivers/char/tpm/tpm_vtpm_proxy.c | 574 ++++++++++++++++++++++++++++++++++++++
 include/uapi/linux/Kbuild         |   1 +
 include/uapi/linux/vtpm_proxy.h   |  36 +++
 5 files changed, 622 insertions(+)
 create mode 100644 drivers/char/tpm/tpm_vtpm_proxy.c
 create mode 100644 include/uapi/linux/vtpm_proxy.h

diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
index 3b84a8b..0eac596 100644
--- a/drivers/char/tpm/Kconfig
+++ b/drivers/char/tpm/Kconfig
@@ -122,5 +122,15 @@ config TCG_CRB
 	  from within Linux.  To compile this driver as a module, choose
 	  M here; the module will be called tpm_crb.
 
+config TCG_VTPM_PROXY
+	tristate "VTPM Proxy Interface"
+	depends on TCG_TPM
+	---help---
+	  This driver proxies for an emulated TPM (vTPM) running in userspace.
+	  A device /dev/vtpmx is provided that creates a device pair
+	  /dev/vtpmX and a server-side file descriptor on which the vTPM
+	  can receive commands.
+
+
 source "drivers/char/tpm/st33zp24/Kconfig"
 endif # TCG_TPM
diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index 56e8f1f..98de5e6 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -23,3 +23,4 @@ obj-$(CONFIG_TCG_IBMVTPM) += tpm_ibmvtpm.o
 obj-$(CONFIG_TCG_TIS_ST33ZP24) += st33zp24/
 obj-$(CONFIG_TCG_XEN) += xen-tpmfront.o
 obj-$(CONFIG_TCG_CRB) += tpm_crb.o
+obj-$(CONFIG_TCG_VTPM_PROXY) += tpm_vtpm_proxy.o
diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
new file mode 100644
index 0000000..a81e814
--- /dev/null
+++ b/drivers/char/tpm/tpm_vtpm_proxy.c
@@ -0,0 +1,574 @@
+/*
+ * Copyright (C) 2015, 2016 IBM Corporation
+ *
+ * Author: Stefan Berger <stefanb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
+ *
+ * Maintained by: <tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
+ *
+ * Device driver for vTPM (vTPM proxy driver)
+ *
+ * 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/types.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+#include <linux/miscdevice.h>
+#include <linux/vtpm_proxy.h>
+#include <linux/file.h>
+#include <linux/anon_inodes.h>
+#include <linux/poll.h>
+#include <linux/compat.h>
+
+#include "tpm.h"
+
+#define VTPM_PROXY_REQ_COMPLETE_FLAG  BIT(0)
+
+struct proxy_dev {
+	struct tpm_chip *chip;
+
+	u32 flags;                   /* public API flags */
+
+	wait_queue_head_t wq;
+
+	struct mutex buf_lock;       /* protect buffer and flags */
+
+	long state;                  /* internal state */
+#define STATE_OPENED_FLAG        BIT(0)
+#define STATE_WAIT_RESPONSE_FLAG BIT(1)  /* waiting for emulator response */
+
+	size_t req_len;              /* length of queued TPM request */
+	size_t resp_len;             /* length of queued TPM response */
+	u8 buffer[TPM_BUFSIZE];      /* request/response buffer */
+};
+
+/* all supported flags */
+#define VTPM_PROXY_FLAGS_ALL  (VTPM_PROXY_FLAG_TPM2)
+
+static void vtpm_proxy_delete_device(struct proxy_dev *proxy_dev);
+
+/*
+ * Functions related to 'server side'
+ */
+
+/**
+ * vtpm_proxy_fops_read - Read TPM commands on 'server side'
+ *
+ * Return value:
+ *	Number of bytes read or negative error code
+ */
+static ssize_t vtpm_proxy_fops_read(struct file *filp, char __user *buf,
+				    size_t count, loff_t *off)
+{
+	struct proxy_dev *proxy_dev = filp->private_data;
+	size_t len;
+	int sig, rc;
+
+	sig = wait_event_interruptible(proxy_dev->wq, proxy_dev->req_len != 0);
+	if (sig)
+		return -EINTR;
+
+	mutex_lock(&proxy_dev->buf_lock);
+
+	len = proxy_dev->req_len;
+
+	if (count < len) {
+		mutex_unlock(&proxy_dev->buf_lock);
+		pr_debug("Invalid size in recv: count=%zd, req_len=%zd\n",
+			 count, len);
+		return -EIO;
+	}
+
+	rc = copy_to_user(buf, proxy_dev->buffer, len);
+	memset(proxy_dev->buffer, 0, len);
+	proxy_dev->req_len = 0;
+
+	if (!rc)
+		proxy_dev->state |= STATE_WAIT_RESPONSE_FLAG;
+
+	mutex_unlock(&proxy_dev->buf_lock);
+
+	if (rc)
+		return -EFAULT;
+
+	return len;
+}
+
+/**
+ * vtpm_proxy_fops_write - Write TPM responses on 'server side'
+ *
+ * Return value:
+ *	Number of bytes read or negative error value
+ */
+static ssize_t vtpm_proxy_fops_write(struct file *filp, const char __user *buf,
+				     size_t count, loff_t *off)
+{
+	struct proxy_dev *proxy_dev = filp->private_data;
+
+	mutex_lock(&proxy_dev->buf_lock);
+
+	if (count > sizeof(proxy_dev->buffer) ||
+	    !(proxy_dev->state & STATE_WAIT_RESPONSE_FLAG)) {
+		mutex_unlock(&proxy_dev->buf_lock);
+		return -EIO;
+	}
+
+	proxy_dev->state &= ~STATE_WAIT_RESPONSE_FLAG;
+
+	proxy_dev->req_len = 0;
+
+	if (copy_from_user(proxy_dev->buffer, buf, count)) {
+		mutex_unlock(&proxy_dev->buf_lock);
+		return -EFAULT;
+	}
+
+	proxy_dev->resp_len = count;
+
+	mutex_unlock(&proxy_dev->buf_lock);
+
+	wake_up_interruptible(&proxy_dev->wq);
+
+	return count;
+}
+
+/*
+ * vtpm_proxy_fops_poll: Poll status on 'server side'
+ *
+ * Return value:
+ *      Poll flags
+ */
+static unsigned int vtpm_proxy_fops_poll(struct file *filp, poll_table *wait)
+{
+	struct proxy_dev *proxy_dev = filp->private_data;
+	unsigned ret;
+
+	poll_wait(filp, &proxy_dev->wq, wait);
+
+	ret = POLLOUT;
+
+	mutex_lock(&proxy_dev->buf_lock);
+
+	if (proxy_dev->req_len)
+		ret |= POLLIN | POLLRDNORM;
+
+	mutex_unlock(&proxy_dev->buf_lock);
+
+	return ret;
+}
+
+/*
+ * vtpm_proxy_fops_open - Open vTPM device on 'server side'
+ *
+ * Called when setting up the anonymous file descriptor
+ */
+static void vtpm_proxy_fops_open(struct file *filp)
+{
+	struct proxy_dev *proxy_dev = filp->private_data;
+
+	proxy_dev->state |= STATE_OPENED_FLAG;
+}
+
+/**
+ * vtpm_proxy_fops_undo_open - counter-part to vtpm_fops_open
+ *
+ * Call to undo vtpm_proxy_fops_open
+ */
+static void vtpm_proxy_fops_undo_open(struct proxy_dev *proxy_dev)
+{
+	mutex_lock(&proxy_dev->buf_lock);
+
+	proxy_dev->state &= ~STATE_OPENED_FLAG;
+
+	mutex_unlock(&proxy_dev->buf_lock);
+
+	/* no more TPM responses -- wake up anyone waiting for them */
+	wake_up_interruptible(&proxy_dev->wq);
+}
+
+/*
+ * vtpm_proxy_fops_release: Close 'server side'
+ *
+ * Return value:
+ *      Always returns 0.
+ */
+static int vtpm_proxy_fops_release(struct inode *inode, struct file *filp)
+{
+	struct proxy_dev *proxy_dev = filp->private_data;
+
+	filp->private_data = NULL;
+
+	vtpm_proxy_delete_device(proxy_dev);
+
+	return 0;
+}
+
+static const struct file_operations vtpm_proxy_fops = {
+	.owner = THIS_MODULE,
+	.llseek = no_llseek,
+	.read = vtpm_proxy_fops_read,
+	.write = vtpm_proxy_fops_write,
+	.poll = vtpm_proxy_fops_poll,
+	.release = vtpm_proxy_fops_release,
+};
+
+/*
+ * Functions invoked by the core TPM driver to send TPM commands to
+ * 'server side' and receive responses from there.
+ */
+
+/*
+ * Called when core TPM driver reads TPM responses from 'server side'
+ *
+ * Return value:
+ *      Number of TPM response bytes read, negative error value otherwise
+ */
+static int vtpm_proxy_tpm_op_recv(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+	struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
+	size_t len;
+
+	if (!proxy_dev)
+		return -EIO;
+
+	/* process gone ? */
+	mutex_lock(&proxy_dev->buf_lock);
+
+	if (!(proxy_dev->state & STATE_OPENED_FLAG)) {
+		mutex_unlock(&proxy_dev->buf_lock);
+		return -EPIPE;
+	}
+
+	len = proxy_dev->resp_len;
+	if (count < len) {
+		dev_err(&chip->dev,
+			"Invalid size in recv: count=%zd, resp_len=%zd\n",
+			count, len);
+		len = -EIO;
+		goto out;
+	}
+
+	memcpy(buf, proxy_dev->buffer, len);
+	proxy_dev->resp_len = 0;
+
+out:
+	mutex_unlock(&proxy_dev->buf_lock);
+
+	return len;
+}
+
+/*
+ * Called when core TPM driver forwards TPM requests to 'server side'.
+ *
+ * Return value:
+ *      0 in case of success, negative error value otherwise.
+ */
+static int vtpm_proxy_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+	struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
+	int rc = 0;
+
+	if (!proxy_dev)
+		return -EIO;
+
+	if (count > sizeof(proxy_dev->buffer)) {
+		dev_err(&chip->dev,
+			"Invalid size in send: count=%zd, buffer size=%zd\n",
+			count, sizeof(proxy_dev->buffer));
+		return -EIO;
+	}
+
+	mutex_lock(&proxy_dev->buf_lock);
+
+	if (!(proxy_dev->state & STATE_OPENED_FLAG)) {
+		mutex_unlock(&proxy_dev->buf_lock);
+		return -EPIPE;
+	}
+
+	proxy_dev->resp_len = 0;
+
+	proxy_dev->req_len = count;
+	memcpy(proxy_dev->buffer, buf, count);
+
+	proxy_dev->state &= ~STATE_WAIT_RESPONSE_FLAG;
+
+	mutex_unlock(&proxy_dev->buf_lock);
+
+	wake_up_interruptible(&proxy_dev->wq);
+
+	return rc;
+}
+
+static void vtpm_proxy_tpm_op_cancel(struct tpm_chip *chip)
+{
+	/* not supported */
+}
+
+static u8 vtpm_proxy_tpm_op_status(struct tpm_chip *chip)
+{
+	struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
+
+	if (proxy_dev->resp_len)
+		return VTPM_PROXY_REQ_COMPLETE_FLAG;
+
+	return 0;
+}
+
+static bool vtpm_proxy_tpm_req_canceled(struct tpm_chip  *chip, u8 status)
+{
+	struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
+	bool ret;
+
+	mutex_lock(&proxy_dev->buf_lock);
+
+	ret = !(proxy_dev->state & STATE_OPENED_FLAG);
+
+	mutex_unlock(&proxy_dev->buf_lock);
+
+	return ret;
+}
+
+static const struct tpm_class_ops vtpm_proxy_tpm_ops = {
+	.recv = vtpm_proxy_tpm_op_recv,
+	.send = vtpm_proxy_tpm_op_send,
+	.cancel = vtpm_proxy_tpm_op_cancel,
+	.status = vtpm_proxy_tpm_op_status,
+	.req_complete_mask = VTPM_PROXY_REQ_COMPLETE_FLAG,
+	.req_complete_val = VTPM_PROXY_REQ_COMPLETE_FLAG,
+	.req_canceled = vtpm_proxy_tpm_req_canceled,
+};
+
+/*
+ * Code related to creation and deletion of device pairs
+ */
+static struct proxy_dev *vtpm_proxy_create_proxy_dev(void)
+{
+	struct proxy_dev *proxy_dev;
+	struct tpm_chip *chip;
+	int err;
+
+	proxy_dev = kzalloc(sizeof(*proxy_dev), GFP_KERNEL);
+	if (proxy_dev == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	init_waitqueue_head(&proxy_dev->wq);
+	mutex_init(&proxy_dev->buf_lock);
+
+	chip = tpm_chip_alloc(NULL, &vtpm_proxy_tpm_ops);
+	if (IS_ERR(chip)) {
+		err = PTR_ERR(chip);
+		goto err_proxy_dev_free;
+	}
+	dev_set_drvdata(&chip->dev, proxy_dev);
+
+	proxy_dev->chip = chip;
+
+	return proxy_dev;
+
+err_proxy_dev_free:
+	kfree(proxy_dev);
+
+	return ERR_PTR(err);
+}
+
+/*
+ * Undo what has been done in vtpm_create_proxy_dev
+ */
+static inline void vtpm_proxy_delete_proxy_dev(struct proxy_dev *proxy_dev)
+{
+	put_device(&proxy_dev->chip->dev); /* frees chip */
+	kfree(proxy_dev);
+}
+
+/*
+ * Create a /dev/tpm%d and 'server side' file descriptor pair
+ *
+ * Return value:
+ *      Returns file pointer on success, an error value otherwise
+ */
+static struct file *vtpm_proxy_create_device(
+				 struct vtpm_proxy_new_dev *vtpm_new_dev)
+{
+	struct proxy_dev *proxy_dev;
+	int rc, fd;
+	struct file *file;
+
+	if (vtpm_new_dev->flags & ~VTPM_PROXY_FLAGS_ALL)
+		return ERR_PTR(-EOPNOTSUPP);
+
+	proxy_dev = vtpm_proxy_create_proxy_dev();
+	if (IS_ERR(proxy_dev))
+		return ERR_CAST(proxy_dev);
+
+	proxy_dev->flags = vtpm_new_dev->flags;
+
+	/* setup an anonymous file for the server-side */
+	fd = get_unused_fd_flags(O_RDWR);
+	if (fd < 0) {
+		rc = fd;
+		goto err_delete_proxy_dev;
+	}
+
+	file = anon_inode_getfile("[vtpms]", &vtpm_proxy_fops, proxy_dev,
+				  O_RDWR);
+	if (IS_ERR(file)) {
+		rc = PTR_ERR(file);
+		goto err_put_unused_fd;
+	}
+
+	/* from now on we can unwind with put_unused_fd() + fput() */
+	/* simulate an open() on the server side */
+	vtpm_proxy_fops_open(file);
+
+	if (proxy_dev->flags & VTPM_PROXY_FLAG_TPM2)
+		proxy_dev->chip->flags |= TPM_CHIP_FLAG_TPM2;
+
+	rc = tpm_chip_register(proxy_dev->chip);
+	if (rc)
+		goto err_vtpm_fput;
+
+	vtpm_new_dev->fd = fd;
+	vtpm_new_dev->major = MAJOR(proxy_dev->chip->dev.devt);
+	vtpm_new_dev->minor = MINOR(proxy_dev->chip->dev.devt);
+	vtpm_new_dev->tpm_num = proxy_dev->chip->dev_num;
+
+	return file;
+
+err_vtpm_fput:
+	put_unused_fd(fd);
+	fput(file);
+
+	return ERR_PTR(rc);
+
+err_put_unused_fd:
+	put_unused_fd(fd);
+
+err_delete_proxy_dev:
+	vtpm_proxy_delete_proxy_dev(proxy_dev);
+
+	return ERR_PTR(rc);
+}
+
+/*
+ * Counter part to vtpm_create_device.
+ */
+static void vtpm_proxy_delete_device(struct proxy_dev *proxy_dev)
+{
+	/*
+	 * A client may hold the 'ops' lock, so let it know that the server
+	 * side shuts down before we try to grab the 'ops' lock when
+	 * unregistering the chip.
+	 */
+	vtpm_proxy_fops_undo_open(proxy_dev);
+
+	tpm_chip_unregister(proxy_dev->chip);
+
+	vtpm_proxy_delete_proxy_dev(proxy_dev);
+}
+
+/*
+ * Code related to the control device /dev/vtpmx
+ */
+
+/*
+ * vtpmx_fops_ioctl: ioctl on /dev/vtpmx
+ *
+ * Return value:
+ *      Returns 0 on success, a negative error code otherwise.
+ */
+static long vtpmx_fops_ioctl(struct file *f, unsigned int ioctl,
+				   unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	struct vtpm_proxy_new_dev *vtpm_new_dev_p;
+	struct vtpm_proxy_new_dev vtpm_new_dev;
+	struct file *file;
+
+	switch (ioctl) {
+	case VTPM_PROXY_IOC_NEW_DEV:
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+		vtpm_new_dev_p = argp;
+		if (copy_from_user(&vtpm_new_dev, vtpm_new_dev_p,
+				   sizeof(vtpm_new_dev)))
+			return -EFAULT;
+		file = vtpm_proxy_create_device(&vtpm_new_dev);
+		if (IS_ERR(file))
+			return PTR_ERR(file);
+		if (copy_to_user(vtpm_new_dev_p, &vtpm_new_dev,
+				 sizeof(vtpm_new_dev))) {
+			put_unused_fd(vtpm_new_dev.fd);
+			fput(file);
+			return -EFAULT;
+		}
+
+		fd_install(vtpm_new_dev.fd, file);
+		return 0;
+
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+
+#ifdef CONFIG_COMPAT
+static long vtpmx_fops_compat_ioctl(struct file *f, unsigned int ioctl,
+					  unsigned long arg)
+{
+	return vtpmx_fops_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
+}
+#endif
+
+static const struct file_operations vtpmx_fops = {
+	.owner = THIS_MODULE,
+	.unlocked_ioctl = vtpmx_fops_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = vtpmx_fops_compat_ioctl,
+#endif
+	.llseek = noop_llseek,
+};
+
+static struct miscdevice vtpmx_miscdev = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "vtpmx",
+	.fops = &vtpmx_fops,
+};
+
+static int vtpmx_init(void)
+{
+	return misc_register(&vtpmx_miscdev);
+}
+
+static void vtpmx_cleanup(void)
+{
+	misc_deregister(&vtpmx_miscdev);
+}
+
+static int __init vtpm_module_init(void)
+{
+	int rc;
+
+	rc = vtpmx_init();
+	if (rc) {
+		pr_err("couldn't create vtpmx device\n");
+		return rc;
+	}
+
+	return 0;
+}
+
+static void __exit vtpm_module_exit(void)
+{
+	vtpmx_cleanup();
+}
+
+module_init(vtpm_module_init);
+module_exit(vtpm_module_exit);
+
+MODULE_AUTHOR("Stefan Berger (stefanb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org)");
+MODULE_DESCRIPTION("vTPM Driver");
+MODULE_VERSION("0.1");
+MODULE_LICENSE("GPL");
diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild
index ebd10e6..ac767ce 100644
--- a/include/uapi/linux/Kbuild
+++ b/include/uapi/linux/Kbuild
@@ -449,6 +449,7 @@ header-y += virtio_scsi.h
 header-y += virtio_types.h
 header-y += vm_sockets.h
 header-y += vt.h
+header-y += vtpm_proxy.h
 header-y += wait.h
 header-y += wanrouter.h
 header-y += watchdog.h
diff --git a/include/uapi/linux/vtpm_proxy.h b/include/uapi/linux/vtpm_proxy.h
new file mode 100644
index 0000000..41e8e22
--- /dev/null
+++ b/include/uapi/linux/vtpm_proxy.h
@@ -0,0 +1,36 @@
+/*
+ * Definitions for the VTPM proxy driver
+ * Copyright (c) 2015, 2016, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef _UAPI_LINUX_VTPM_PROXY_H
+#define _UAPI_LINUX_VTPM_PROXY_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+/* ioctls */
+
+struct vtpm_proxy_new_dev {
+	__u32 flags;         /* input */
+	__u32 tpm_num;       /* output */
+	__u32 fd;            /* output */
+	__u32 major;         /* output */
+	__u32 minor;         /* output */
+};
+
+/* above flags */
+#define VTPM_PROXY_FLAG_TPM2  1  /* emulator is TPM 2 */
+
+#define VTPM_PROXY_IOC_NEW_DEV   _IOWR(0xa1, 0x00, struct vtpm_proxy_new_dev)
+
+#endif /* _UAPI_LINUX_VTPM_PROXY_H */
-- 
2.4.3


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[PATCH v10 4/5] tpm: Initialize TPM and get durations and timeouts

[Stefan Berger]

Add the retrieval of TPM 1.2 durations and timeouts. Since this requires
the startup of the TPM, do this for TPM 1.2 and TPM 2.

Signed-off-by: Stefan Berger <stefanb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>

CC: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
CC: linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
CC: linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
---
 drivers/char/tpm/tpm_vtpm_proxy.c | 96 +++++++++++++++++++++++++++++++++++----
 1 file changed, 86 insertions(+), 10 deletions(-)

diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
index a81e814..3b09458 100644
--- a/drivers/char/tpm/tpm_vtpm_proxy.c
+++ b/drivers/char/tpm/tpm_vtpm_proxy.c
@@ -45,11 +45,15 @@ struct proxy_dev {
 	size_t req_len;              /* length of queued TPM request */
 	size_t resp_len;             /* length of queued TPM response */
 	u8 buffer[TPM_BUFSIZE];      /* request/response buffer */
+
+	struct work_struct work;     /* task that retrieves TPM timeouts */
 };
 
 /* all supported flags */
 #define VTPM_PROXY_FLAGS_ALL  (VTPM_PROXY_FLAG_TPM2)
 
+static struct workqueue_struct *workqueue;
+
 static void vtpm_proxy_delete_device(struct proxy_dev *proxy_dev);
 
 /*
@@ -69,12 +73,19 @@ static ssize_t vtpm_proxy_fops_read(struct file *filp, char __user *buf,
 	size_t len;
 	int sig, rc;
 
-	sig = wait_event_interruptible(proxy_dev->wq, proxy_dev->req_len != 0);
+	sig = wait_event_interruptible(proxy_dev->wq,
+		proxy_dev->req_len != 0 ||
+		!(proxy_dev->state & STATE_OPENED_FLAG));
 	if (sig)
 		return -EINTR;
 
 	mutex_lock(&proxy_dev->buf_lock);
 
+	if (!(proxy_dev->state & STATE_OPENED_FLAG)) {
+		mutex_unlock(&proxy_dev->buf_lock);
+		return -EPIPE;
+	}
+
 	len = proxy_dev->req_len;
 
 	if (count < len) {
@@ -112,6 +123,11 @@ static ssize_t vtpm_proxy_fops_write(struct file *filp, const char __user *buf,
 
 	mutex_lock(&proxy_dev->buf_lock);
 
+	if (!(proxy_dev->state & STATE_OPENED_FLAG)) {
+		mutex_unlock(&proxy_dev->buf_lock);
+		return -EPIPE;
+	}
+
 	if (count > sizeof(proxy_dev->buffer) ||
 	    !(proxy_dev->state & STATE_WAIT_RESPONSE_FLAG)) {
 		mutex_unlock(&proxy_dev->buf_lock);
@@ -156,6 +172,9 @@ static unsigned int vtpm_proxy_fops_poll(struct file *filp, poll_table *wait)
 	if (proxy_dev->req_len)
 		ret |= POLLIN | POLLRDNORM;
 
+	if (!(proxy_dev->state & STATE_OPENED_FLAG))
+		ret |= POLLHUP;
+
 	mutex_unlock(&proxy_dev->buf_lock);
 
 	return ret;
@@ -343,6 +362,55 @@ static const struct tpm_class_ops vtpm_proxy_tpm_ops = {
 };
 
 /*
+ * Code related to the startup of the TPM 2 and startup of TPM 1.2 +
+ * retrieval of timeouts and durations.
+ */
+
+static void vtpm_proxy_work(struct work_struct *work)
+{
+	struct proxy_dev *proxy_dev = container_of(work, struct proxy_dev,
+						   work);
+	int rc;
+
+	if (proxy_dev->flags & VTPM_PROXY_FLAG_TPM2)
+		rc = tpm2_startup(proxy_dev->chip, TPM2_SU_CLEAR);
+	else
+		rc = tpm_get_timeouts(proxy_dev->chip);
+
+	if (rc)
+		goto err;
+
+	rc = tpm_chip_register(proxy_dev->chip);
+	if (rc)
+		goto err;
+
+	return;
+
+err:
+	vtpm_proxy_fops_undo_open(proxy_dev);
+}
+
+/*
+ * vtpm_proxy_work_stop: make sure the work has finished
+ *
+ * This function is useful when user space closed the fd
+ * while the driver still determines timeouts.
+ */
+static void vtpm_proxy_work_stop(struct proxy_dev *proxy_dev)
+{
+	vtpm_proxy_fops_undo_open(proxy_dev);
+	flush_work(&proxy_dev->work);
+}
+
+/*
+ * vtpm_proxy_work_start: Schedule the work for TPM 1.2 & 2 initialization
+ */
+static inline void vtpm_proxy_work_start(struct proxy_dev *proxy_dev)
+{
+	queue_work(workqueue, &proxy_dev->work);
+}
+
+/*
  * Code related to creation and deletion of device pairs
  */
 static struct proxy_dev *vtpm_proxy_create_proxy_dev(void)
@@ -357,6 +425,7 @@ static struct proxy_dev *vtpm_proxy_create_proxy_dev(void)
 
 	init_waitqueue_head(&proxy_dev->wq);
 	mutex_init(&proxy_dev->buf_lock);
+	INIT_WORK(&proxy_dev->work, vtpm_proxy_work);
 
 	chip = tpm_chip_alloc(NULL, &vtpm_proxy_tpm_ops);
 	if (IS_ERR(chip)) {
@@ -427,9 +496,7 @@ static struct file *vtpm_proxy_create_device(
 	if (proxy_dev->flags & VTPM_PROXY_FLAG_TPM2)
 		proxy_dev->chip->flags |= TPM_CHIP_FLAG_TPM2;
 
-	rc = tpm_chip_register(proxy_dev->chip);
-	if (rc)
-		goto err_vtpm_fput;
+	vtpm_proxy_work_start(proxy_dev);
 
 	vtpm_new_dev->fd = fd;
 	vtpm_new_dev->major = MAJOR(proxy_dev->chip->dev.devt);
@@ -438,12 +505,6 @@ static struct file *vtpm_proxy_create_device(
 
 	return file;
 
-err_vtpm_fput:
-	put_unused_fd(fd);
-	fput(file);
-
-	return ERR_PTR(rc);
-
 err_put_unused_fd:
 	put_unused_fd(fd);
 
@@ -458,6 +519,8 @@ err_delete_proxy_dev:
  */
 static void vtpm_proxy_delete_device(struct proxy_dev *proxy_dev)
 {
+	vtpm_proxy_work_stop(proxy_dev);
+
 	/*
 	 * A client may hold the 'ops' lock, so let it know that the server
 	 * side shuts down before we try to grab the 'ops' lock when
@@ -557,11 +620,24 @@ static int __init vtpm_module_init(void)
 		return rc;
 	}
 
+	workqueue = create_workqueue("tpm-vtpm");
+	if (!workqueue) {
+		pr_err("couldn't create workqueue\n");
+		rc = -ENOMEM;
+		goto err_vtpmx_cleanup;
+	}
+
 	return 0;
+
+err_vtpmx_cleanup:
+	vtpmx_cleanup();
+
+	return rc;
 }
 
 static void __exit vtpm_module_exit(void)
 {
+	destroy_workqueue(workqueue);
 	vtpmx_cleanup();
 }
 
-- 
2.4.3


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Re: [PATCH v10 4/5] tpm: Initialize TPM and get durations and timeouts

[Jason Gunthorpe]

On Fri, Apr 15, 2016 at 09:50:15AM -0400, Stefan Berger wrote:

> @@ -69,12 +73,19 @@ static ssize_t vtpm_proxy_fops_read(struct file *filp, char __user *buf,
>  	size_t len;
>  	int sig, rc;
>  
> -	sig = wait_event_interruptible(proxy_dev->wq, proxy_dev->req_len != 0);
> +	sig = wait_event_interruptible(proxy_dev->wq,
> +		proxy_dev->req_len != 0 ||
> +		!(proxy_dev->state & STATE_OPENED_FLAG));
>  	if (sig)
>  		return -EINTR;

This hunk and related doesn't look like it belongs in this patch?

Suggest just merging this into the prior patch and be done with it, not
really any reason to have two patches anymore.

I think everything that was brought up is taken care of now..

One last read through..

> static int vtpm_proxy_tpm_op_recv(struct tpm_chip *chip, u8 *buf, size_t count)
> {
>	struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
>	if (!proxy_dev)
>		return -EIO;

Is that actually possible? It shouldn't be. If not please drop it an
related.

For both:
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

Jason

[PATCH v10 5/5] tpm: Add documentation for the tpm_vtpm_proxy device driver

[Stefan Berger]

Add documentation for the tpm_vtpm device driver that implements
support for providing TPM functionality to Linux containers.

Parts of this documentation were recycled from the Xen vTPM
device driver documentation.

Update the documentation for the ioctl numbers.

Signed-off-by: Stefan Berger <stefanb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>

CC: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
CC: linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
CC: linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
---
 Documentation/ioctl/ioctl-number.txt |  1 +
 Documentation/tpm/tpm_vtpm_proxy.txt | 71 ++++++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+)
 create mode 100644 Documentation/tpm/tpm_vtpm_proxy.txt

diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 91261a3..7dbec90 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -303,6 +303,7 @@ Code  Seq#(hex)	Include File		Comments
 					<mailto:buk-KMFVLCTwZAcb1SvskN2V4Q@public.gmane.org>
 0xA0	all	linux/sdp/sdp.h		Industrial Device Project
 					<mailto:kenji-/mrfy+mawvNBDgjK7y7TUQ@public.gmane.org>
+0xA1	0	linux/vtpm_proxy.h	TPM Emulator Proxy Driver
 0xA2	00-0F	arch/tile/include/asm/hardwall.h
 0xA3	80-8F	Port ACL		in development:
 					<mailto:tlewis-mn4gwa5WIIQysxA8WJXlww@public.gmane.org>
diff --git a/Documentation/tpm/tpm_vtpm_proxy.txt b/Documentation/tpm/tpm_vtpm_proxy.txt
new file mode 100644
index 0000000..30d1902
--- /dev/null
+++ b/Documentation/tpm/tpm_vtpm_proxy.txt
@@ -0,0 +1,71 @@
+Virtual TPM Proxy Driver for Linux Containers
+
+Authors: Stefan Berger (IBM)
+
+This document describes the virtual Trusted Platform Module (vTPM)
+proxy device driver for Linux containers.
+
+INTRODUCTION
+------------
+
+The goal of this work is to provide TPM functionality to each Linux
+container. This allows programs to interact with a TPM in a container
+the same way they interact with a TPM on the physical system. Each
+container gets its own unique, emulated, software TPM.
+
+
+DESIGN
+------
+
+To make an emulated software TPM available to each container, the container
+management stack needs to create a device pair consisting of a client TPM
+character device /dev/tpmX (with X=0,1,2...) and a 'server side' file
+descriptor. The former is moved into the container by creating a character
+device with the appropriate major and minor numbers while the file descriptor
+is passed to the TPM emulator. Software inside the container can then send
+TPM commands using the character device and the emulator will receive the
+commands via the file descriptor and use it for sending back responses.
+
+To support this, the virtual TPM proxy driver provides a device /dev/vtpmx
+that is used to create device pairs using an ioctl. The ioctl takes as
+an input flags for configuring the device. The flags  for example indicate
+whether TPM 1.2 or TPM 2 functionality is supported by the TPM emulator.
+The result of the ioctl are the file descriptor for the 'server side'
+as well as the major and minor numbers of the character device that was created.
+Besides that the number of the TPM character device is return. If for
+example /dev/tpm10 was created, the number (dev_num) 10 is returned.
+
+The following is the data structure of the TPM_PROXY_IOC_NEW_DEV ioctl:
+
+struct vtpm_proxy_new_dev {
+	__u32 flags;         /* input */
+	__u32 tpm_num;       /* output */
+	__u32 fd;            /* output */
+	__u32 major;         /* output */
+	__u32 minor;         /* output */
+};
+
+Note that if unsupported flags are passed to the device driver, the ioctl will
+fail and errno will be set to EOPNOTSUPP. Similarly, if an unsupported ioctl is
+called on the device driver, the ioctl will fail and errno will be set to
+ENOTTY.
+
+See /usr/include/linux/vtpm_proxy.h for definitions related to the public interface
+of this vTPM device driver.
+
+Once the device has been created, the driver will immediately try to talk
+to the TPM. All commands from the driver can be read from the file descriptor
+returned by the ioctl. The commands should be responded to immediately.
+
+Depending on the version of TPM the following commands will be sent by the
+driver:
+
+- TPM 1.2:
+  - the driver will send a TPM_Startup command to the TPM emulator
+  - the driver will send commands to read the command durations and
+    interface timeouts from the TPM emulator
+- TPM 2:
+  - the driver will send a TPM2_Startup command to the TPM emulator
+
+The TPM device /dev/tpmX will only appear if all of the relevant commands
+were responded to properly.
-- 
2.4.3


------------------------------------------------------------------------------
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