[PATCH 0/6] in-kernel resource manager

[PATCH 0/6] in-kernel resource manager

[Jarkko Sakkinen]

This patch set adds support for TPM spaces that provide an isolated
for transient objects and HMAC and policy sessions. A space is swapped
into TPM volatile memory only when it is used and swapped out after
the use.

There's a test script for trying out TPM spaces in

  git://git.infradead.org/users/jjs/tpm2-scripts.git

A simple smoke test can be run by

  sudo python -m unittest -v tpm2_smoke.SpaceTest   

James Bottomley (3):
  tpm: split out tpm-dev.c into tpm-dev.c and tpm-common-dev.c
  tpm: expose spaces via a device link /dev/tpms<n>
  tpm2: add session handle context saving and restoring to the space
    code

Jarkko Sakkinen (3):
  tpm: validate TPM 2.0 commands
  tpm: export tpm2_flush_context_cmd
  tpm: infrastructure for TPM spaces

 drivers/char/tpm/Makefile         |   3 +-
 drivers/char/tpm/tpm-chip.c       |  86 +++++++-
 drivers/char/tpm/tpm-dev-common.c | 148 +++++++++++++
 drivers/char/tpm/tpm-dev.c        | 143 ++----------
 drivers/char/tpm/tpm-dev.h        |  27 +++
 drivers/char/tpm/tpm-interface.c  | 114 +++++++---
 drivers/char/tpm/tpm-sysfs.c      |   2 +-
 drivers/char/tpm/tpm.h            |  48 +++-
 drivers/char/tpm/tpm2-cmd.c       | 166 ++++++++++----
 drivers/char/tpm/tpm2-space.c     | 450 ++++++++++++++++++++++++++++++++++++++
 drivers/char/tpm/tpms-dev.c       |  65 ++++++
 11 files changed, 1040 insertions(+), 212 deletions(-)
 create mode 100644 drivers/char/tpm/tpm-dev-common.c
 create mode 100644 drivers/char/tpm/tpm-dev.h
 create mode 100644 drivers/char/tpm/tpm2-space.c
 create mode 100644 drivers/char/tpm/tpms-dev.c

-- 
2.9.3

[PATCH 1/6] tpm: validate TPM 2.0 commands

[Jarkko Sakkinen]

Check for every TPM 2.0 command that the command code is supported and
the command buffer has at least the length that can contain the header
and the handle area.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
 drivers/char/tpm/tpm-interface.c | 38 +++++++++++++++++++-
 drivers/char/tpm/tpm.h           | 14 ++++++++
 drivers/char/tpm/tpm2-cmd.c      | 77 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 128 insertions(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 087748b..f760c48 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -328,6 +328,42 @@ unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 }
 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 
+static bool tpm_validate_command(struct tpm_chip *chip, const u8 *cmd,
+				 size_t len)
+{
+	const struct tpm_input_header *header = (const void *)cmd;
+	int i;
+	u32 cc;
+	u32 attrs;
+	unsigned int nr_handles;
+
+	if (len < TPM_HEADER_SIZE)
+		return false;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) {
+		cc = be32_to_cpu(header->ordinal);
+
+		i = tpm2_find_cc(chip, cc);
+		if (i < 0) {
+			dev_dbg(&chip->dev, "0x%04X is an invalid command\n",
+				cc);
+			return false;
+		}
+
+		attrs = chip->cc_attrs_tbl[i];
+		nr_handles =
+			4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0));
+		if (len < TPM_HEADER_SIZE + 4 * nr_handles)
+			goto err_len;
+	}
+
+	return true;
+err_len:
+	dev_dbg(&chip->dev,
+		"%s: insufficient command length %zu", __func__, len);
+	return false;
+}
+
 /**
  * tmp_transmit - Internal kernel interface to transmit TPM commands.
  *
@@ -347,7 +383,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
 	u32 count, ordinal;
 	unsigned long stop;
 
-	if (bufsiz < TPM_HEADER_SIZE)
+	if (!tpm_validate_command(chip, buf, bufsiz))
 		return -EINVAL;
 
 	if (bufsiz > TPM_BUFSIZE)
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 6b4e7aa..4f21e42 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -127,15 +127,25 @@ enum tpm2_permanent_handles {
 };
 
 enum tpm2_capabilities {
+	TPM2_CAP_COMMANDS	= 2,
 	TPM2_CAP_PCRS		= 5,
 	TPM2_CAP_TPM_PROPERTIES = 6,
 };
 
+enum tpm2_properties {
+	TPM_PT_TOTAL_COMMANDS	= 0x0129,
+};
+
 enum tpm2_startup_types {
 	TPM2_SU_CLEAR	= 0x0000,
 	TPM2_SU_STATE	= 0x0001,
 };
 
+enum tpm2_cc_attrs {
+	TPM2_CC_ATTR_CHANDLES	= 25,
+	TPM2_CC_ATTR_RHANDLE	= 28,
+};
+
 #define TPM_VID_INTEL    0x8086
 #define TPM_VID_WINBOND  0x1050
 #define TPM_VID_STM      0x104A
@@ -199,6 +209,9 @@ struct tpm_chip {
 	acpi_handle acpi_dev_handle;
 	char ppi_version[TPM_PPI_VERSION_LEN + 1];
 #endif /* CONFIG_ACPI */
+
+	u32 nr_commands;
+	u32 *cc_attrs_tbl;
 };
 
 #define to_tpm_chip(d) container_of(d, struct tpm_chip, dev)
@@ -555,4 +568,5 @@ void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type);
 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal);
 int tpm2_probe(struct tpm_chip *chip);
 ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip);
+int tpm2_find_cc(struct tpm_chip *chip, u32 cc);
 #endif
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 10f97e6..fe57fce 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -997,6 +997,68 @@ int tpm2_probe(struct tpm_chip *chip)
 }
 EXPORT_SYMBOL_GPL(tpm2_probe);
 
+static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
+{
+	struct tpm_buf buf;
+	u32 nr_commands;
+	u32 *attrs;
+	int i;
+	int rc;
+
+	rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
+	if (rc)
+		goto out;
+
+	if (nr_commands > 0xFFFFF) {
+		rc = -EFAULT;
+		goto out;
+	}
+
+	chip->cc_attrs_tbl = devm_kzalloc(&chip->dev, 4 * nr_commands,
+					  GFP_KERNEL);
+
+	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+	if (rc)
+		goto out;
+
+	tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
+	tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
+	tpm_buf_append_u32(&buf, nr_commands);
+
+	rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 9 + 4 * nr_commands,
+			      0, NULL);
+	if (rc) {
+		tpm_buf_destroy(&buf);
+		goto out;
+	}
+
+	if (nr_commands !=
+	    be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
+		tpm_buf_destroy(&buf);
+		goto out;
+	}
+
+	chip->nr_commands = nr_commands;
+
+	attrs = (u32 *)&buf.data[TPM_HEADER_SIZE + 9];
+	for (i = 0; i < nr_commands; i++, attrs++) {
+		chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
+		/* handle is in the body  */
+		if ((chip->cc_attrs_tbl[i] & 0xFFFF) == TPM2_CC_FLUSH_CONTEXT) {
+			chip->cc_attrs_tbl[i] &=
+				~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
+			chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
+		}
+	}
+
+	tpm_buf_destroy(&buf);
+
+out:
+	if (rc > 0)
+		rc = -ENODEV;
+	return rc;
+}
+
 /**
  * tpm2_auto_startup - Perform the standard automatic TPM initialization
  *                     sequence
@@ -1031,6 +1093,10 @@ int tpm2_auto_startup(struct tpm_chip *chip)
 	}
 
 	rc = tpm2_get_pcr_allocation(chip);
+	if (rc)
+		goto out;
+
+	rc = tpm2_get_cc_attrs_tbl(chip);
 
 out:
 	if (rc > 0)
@@ -1114,3 +1180,14 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
 
 	return rc;
 }
+
+int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
+{
+	int i;
+
+	for (i = 0; i < chip->nr_commands; i++)
+		if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
+			return i;
+
+	return -1;
+}
-- 
2.9.3

[PATCH 2/6] tpm: export tpm2_flush_context_cmd

[Jarkko Sakkinen]

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
 drivers/char/tpm/tpm.h      |  2 ++
 drivers/char/tpm/tpm2-cmd.c | 62 +++++++++++++++++++++------------------------
 2 files changed, 31 insertions(+), 33 deletions(-)

diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 4f21e42..ba483f1 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -554,6 +554,8 @@ int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf);
 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
 		    struct tpm2_digest *digests);
 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max);
+void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
+			    unsigned int flags);
 int tpm2_seal_trusted(struct tpm_chip *chip,
 		      struct trusted_key_payload *payload,
 		      struct trusted_key_options *options);
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index fe57fce..86565a9 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -419,6 +419,35 @@ static const struct tpm_input_header tpm2_get_tpm_pt_header = {
 };
 
 /**
+ * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
+ * @chip: TPM chip to use
+ * @payload: the key data in clear and encrypted form
+ * @options: authentication values and other options
+ *
+ * Return: same as with tpm_transmit_cmd
+ */
+void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
+			    unsigned int flags)
+{
+	struct tpm_buf buf;
+	int rc;
+
+	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
+	if (rc) {
+		dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
+			 handle);
+		return;
+	}
+
+	tpm_buf_append_u32(&buf, handle);
+
+	(void) tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, flags,
+				"flushing context");
+
+	tpm_buf_destroy(&buf);
+}
+
+/**
  * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
  *
  * @buf: an allocated tpm_buf instance
@@ -628,39 +657,6 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
 }
 
 /**
- * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
- *
- * @chip: TPM chip to use
- * @handle: the key data in clear and encrypted form
- * @flags: tpm transmit flags
- *
- * Return: Same as with tpm_transmit_cmd.
- */
-static void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
-				   unsigned int flags)
-{
-	struct tpm_buf buf;
-	int rc;
-
-	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
-	if (rc) {
-		dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
-			 handle);
-		return;
-	}
-
-	tpm_buf_append_u32(&buf, handle);
-
-	rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, flags,
-			      "flushing context");
-	if (rc)
-		dev_warn(&chip->dev, "0x%08x was not flushed, rc=%d\n", handle,
-			 rc);
-
-	tpm_buf_destroy(&buf);
-}
-
-/**
  * tpm2_unseal_cmd() - execute a TPM2_Unload command
  *
  * @chip: TPM chip to use
-- 
2.9.3

Re: [PATCH 2/6] tpm: export tpm2_flush_context_cmd

[Jason Gunthorpe]

>  /**
> + * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
> + * @chip: TPM chip to use
> + * @payload: the key data in clear and encrypted form
> + * @options: authentication values and other options
> + *
> + * Return: same as with tpm_transmit_cmd
> + */
> +void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
> +			    unsigned int flags)

Why did you move the function in the same file? Adding a prototype
shouldn't require that..

Jason

Re: [PATCH 2/6] tpm: export tpm2_flush_context_cmd

[Jarkko Sakkinen]

On Wed, Feb 08, 2017 at 10:58:30AM -0700, Jason Gunthorpe wrote:
> >  /**
> > + * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
> > + * @chip: TPM chip to use
> > + * @payload: the key data in clear and encrypted form
> > + * @options: authentication values and other options
> > + *
> > + * Return: same as with tpm_transmit_cmd
> > + */
> > +void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
> > +			    unsigned int flags)
> 
> Why did you move the function in the same file? Adding a prototype
> shouldn't require that..
> 
> Jason

To be logically positioned in the same way as it is in the header.

It cannot in-between the helper functions for tpm2_seal_trusted().

/Jarkko

[PATCH 3/6] tpm: infrastructure for TPM spaces

[Jarkko Sakkinen]

Added ability to tpm_transmit() to supply a TPM space that contains
mapping from virtual handles to physical handles and backing storage for
swapping transient objects. TPM space is isolated from other users of
the TPM.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
 drivers/char/tpm/Makefile        |   2 +-
 drivers/char/tpm/tpm-chip.c      |   7 +
 drivers/char/tpm/tpm-dev.c       |   2 +-
 drivers/char/tpm/tpm-interface.c |  63 +++++---
 drivers/char/tpm/tpm-sysfs.c     |   2 +-
 drivers/char/tpm/tpm.h           |  26 ++-
 drivers/char/tpm/tpm2-cmd.c      |  33 ++--
 drivers/char/tpm/tpm2-space.c    | 341 +++++++++++++++++++++++++++++++++++++++
 8 files changed, 428 insertions(+), 48 deletions(-)
 create mode 100644 drivers/char/tpm/tpm2-space.c

diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index 3d386a8..8f07fcf 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -3,7 +3,7 @@
 #
 obj-$(CONFIG_TCG_TPM) += tpm.o
 tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
-		tpm1_eventlog.o tpm2_eventlog.o
+	 tpm1_eventlog.o tpm2_eventlog.o tpm2-space.o
 tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
 tpm-$(CONFIG_OF) += tpm_of.o
 obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index c406343..993b9ae 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -128,6 +128,7 @@ static void tpm_dev_release(struct device *dev)
 	mutex_unlock(&idr_lock);
 
 	kfree(chip->log.bios_event_log);
+	kfree(chip->work_space.context_buf);
 	kfree(chip);
 }
 
@@ -189,6 +190,12 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
 	chip->cdev.owner = THIS_MODULE;
 	chip->cdev.kobj.parent = &chip->dev.kobj;
 
+	chip->work_space.context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!chip->work_space.context_buf) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
 	return chip;
 
 out:
diff --git a/drivers/char/tpm/tpm-dev.c b/drivers/char/tpm/tpm-dev.c
index 02a8850..414553b 100644
--- a/drivers/char/tpm/tpm-dev.c
+++ b/drivers/char/tpm/tpm-dev.c
@@ -147,7 +147,7 @@ static ssize_t tpm_write(struct file *file, const char __user *buf,
 		mutex_unlock(&priv->buffer_mutex);
 		return -EPIPE;
 	}
-	out_size = tpm_transmit(priv->chip, priv->data_buffer,
+	out_size = tpm_transmit(priv->chip, NULL, priv->data_buffer,
 				sizeof(priv->data_buffer), 0);
 
 	tpm_put_ops(priv->chip);
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index f760c48..7e1b557 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -376,10 +376,11 @@ static bool tpm_validate_command(struct tpm_chip *chip, const u8 *cmd,
  *     0 when the operation is successful.
  *     A negative number for system errors (errno).
  */
-ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
-		     unsigned int flags)
+ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
+		     u8 *buf, size_t bufsiz, unsigned int flags)
 {
-	ssize_t rc;
+	int rc;
+	ssize_t len = 0;
 	u32 count, ordinal;
 	unsigned long stop;
 
@@ -405,10 +406,14 @@ ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
 	if (chip->dev.parent)
 		pm_runtime_get_sync(chip->dev.parent);
 
+	rc = tpm2_prepare_space(chip, space, ordinal, buf);
+	if (rc)
+		goto out;
+
 	rc = chip->ops->send(chip, (u8 *) buf, count);
 	if (rc < 0) {
 		dev_err(&chip->dev,
-			"tpm_transmit: tpm_send: error %zd\n", rc);
+			"tpm_transmit: tpm_send: error %d\n", rc);
 		goto out;
 	}
 
@@ -441,17 +446,23 @@ ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
 	goto out;
 
 out_recv:
-	rc = chip->ops->recv(chip, (u8 *) buf, bufsiz);
-	if (rc < 0)
+	len = chip->ops->recv(chip, (u8 *) buf, bufsiz);
+	if (len < 0) {
 		dev_err(&chip->dev,
-			"tpm_transmit: tpm_recv: error %zd\n", rc);
+			"tpm_transmit: tpm_recv: error %d\n", rc);
+		rc = len;
+		goto out;
+	}
+
+	rc = tpm2_commit_space(chip, space, ordinal, buf, len);
+
 out:
 	if (chip->dev.parent)
 		pm_runtime_put_sync(chip->dev.parent);
 
 	if (!(flags & TPM_TRANSMIT_UNLOCKED))
 		mutex_unlock(&chip->tpm_mutex);
-	return rc;
+	return rc ? rc : len;
 }
 
 /**
@@ -470,15 +481,16 @@ ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
  *     A negative number for system errors (errno).
  *     A positive number for a TPM error.
  */
-ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *buf,
-			 size_t bufsiz, size_t min_rsp_body_length,
-			 unsigned int flags, const char *desc)
+ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
+			 const void *buf, size_t bufsiz,
+			 size_t min_rsp_body_length, unsigned int flags,
+			 const char *desc)
 {
 	const struct tpm_output_header *header;
 	int err;
 	ssize_t len;
 
-	len = tpm_transmit(chip, (const u8 *)buf, bufsiz, flags);
+	len = tpm_transmit(chip, space, (u8 *)buf, bufsiz, flags);
 	if (len <  0)
 		return len;
 	else if (len < TPM_HEADER_SIZE)
@@ -537,7 +549,7 @@ ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
 		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 		tpm_cmd.params.getcap_in.subcap = cpu_to_be32(subcap_id);
 	}
-	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
+	rc = tpm_transmit_cmd(chip, NULL, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 			      min_cap_length, 0, desc);
 	if (!rc)
 		*cap = tpm_cmd.params.getcap_out.cap;
@@ -561,7 +573,8 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
 	start_cmd.header.in = tpm_startup_header;
 
 	start_cmd.params.startup_in.startup_type = startup_type;
-	return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
+	return tpm_transmit_cmd(chip, NULL, &start_cmd,
+				TPM_INTERNAL_RESULT_SIZE, 0,
 				0, "attempting to start the TPM");
 }
 
@@ -718,8 +731,8 @@ static int tpm_continue_selftest(struct tpm_chip *chip)
 	struct tpm_cmd_t cmd;
 
 	cmd.header.in = continue_selftest_header;
-	rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0, 0,
-			      "continue selftest");
+	rc = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
+			      0, 0, "continue selftest");
 	return rc;
 }
 
@@ -739,7 +752,7 @@ int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 
 	cmd.header.in = pcrread_header;
 	cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
-	rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
+	rc = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE,
 			      READ_PCR_RESULT_BODY_SIZE, 0,
 			      "attempting to read a pcr value");
 
@@ -851,7 +864,7 @@ int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 	cmd.header.in = pcrextend_header;
 	cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 	memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
-	rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
+	rc = tpm_transmit_cmd(chip, NULL, &cmd, EXTEND_PCR_RESULT_SIZE,
 			      EXTEND_PCR_RESULT_BODY_SIZE, 0,
 			      "attempting extend a PCR value");
 
@@ -956,8 +969,8 @@ int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 	if (chip == NULL)
 		return -ENODEV;
 
-	rc = tpm_transmit_cmd(chip, cmd, buflen, 0, 0, "attempting tpm_cmd");
-
+	rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, 0,
+			      "attempting tpm_cmd");
 	tpm_put_ops(chip);
 	return rc;
 }
@@ -1058,16 +1071,16 @@ int tpm_pm_suspend(struct device *dev)
 		cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
 		memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
 		       TPM_DIGEST_SIZE);
-		rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
-				     EXTEND_PCR_RESULT_BODY_SIZE, 0,
+		rc = tpm_transmit_cmd(chip, NULL, &cmd, EXTEND_PCR_RESULT_SIZE,
+				      EXTEND_PCR_RESULT_BODY_SIZE, 0,
 				      "extending dummy pcr before suspend");
 	}
 
 	/* now do the actual savestate */
 	for (try = 0; try < TPM_RETRY; try++) {
 		cmd.header.in = savestate_header;
-		rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, 0,
-				      0, NULL);
+		rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
+				      0, 0, NULL);
 
 		/*
 		 * If the TPM indicates that it is too busy to respond to
@@ -1150,7 +1163,7 @@ int tpm_get_random(u32 chip_num, u8 *out, size_t max)
 		tpm_cmd.header.in = tpm_getrandom_header;
 		tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
 
-		err = tpm_transmit_cmd(chip, &tpm_cmd,
+		err = tpm_transmit_cmd(chip, NULL, &tpm_cmd,
 				       TPM_GETRANDOM_RESULT_SIZE + num_bytes,
 				       offsetof(struct tpm_getrandom_out,
 						rng_data),
diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index 2f596d7..55405db 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -40,7 +40,7 @@ static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
 	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,
+	err = tpm_transmit_cmd(chip, NULL, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 			       READ_PUBEK_RESULT_MIN_BODY_SIZE, 0,
 			       "attempting to read the PUBEK");
 	if (err)
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index ba483f1..ba10973 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -89,10 +89,13 @@ enum tpm2_structures {
 };
 
 enum tpm2_return_codes {
+	TPM2_RC_SUCCESS		= 0x0000,
 	TPM2_RC_HASH		= 0x0083, /* RC_FMT1 */
+	TPM2_RC_HANDLE		= 0x008B,
 	TPM2_RC_INITIALIZE	= 0x0100, /* RC_VER1 */
 	TPM2_RC_DISABLED	= 0x0120,
 	TPM2_RC_TESTING		= 0x090A, /* RC_WARN */
+	TPM2_RC_REFERENCE_H0	= 0x0910,
 };
 
 enum tpm2_algorithms {
@@ -114,6 +117,8 @@ enum tpm2_command_codes {
 	TPM2_CC_CREATE		= 0x0153,
 	TPM2_CC_LOAD		= 0x0157,
 	TPM2_CC_UNSEAL		= 0x015E,
+	TPM2_CC_CONTEXT_LOAD	= 0x0161,
+	TPM2_CC_CONTEXT_SAVE	= 0x0162,
 	TPM2_CC_FLUSH_CONTEXT	= 0x0165,
 	TPM2_CC_GET_CAPABILITY	= 0x017A,
 	TPM2_CC_GET_RANDOM	= 0x017B,
@@ -152,6 +157,11 @@ enum tpm2_cc_attrs {
 
 #define TPM_PPI_VERSION_LEN		3
 
+struct tpm_space {
+	u32 context_tbl[3];
+	u8 *context_buf;
+};
+
 enum tpm_chip_flags {
 	TPM_CHIP_FLAG_TPM2		= BIT(1),
 	TPM_CHIP_FLAG_IRQ		= BIT(2),
@@ -210,6 +220,7 @@ struct tpm_chip {
 	char ppi_version[TPM_PPI_VERSION_LEN + 1];
 #endif /* CONFIG_ACPI */
 
+	struct tpm_space work_space;
 	u32 nr_commands;
 	u32 *cc_attrs_tbl;
 };
@@ -506,10 +517,11 @@ enum tpm_transmit_flags {
 	TPM_TRANSMIT_UNLOCKED	= BIT(0),
 };
 
-ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
-		     unsigned int flags);
-ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *buf, size_t bufsiz,
-			 size_t min_rsp_body_len, unsigned int flags,
+ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
+		     u8 *buf, size_t bufsiz, unsigned int flags);
+ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
+			 const void *buf, size_t bufsiz,
+			 size_t min_rsp_body_length, unsigned int flags,
 			 const char *desc);
 ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
 		   const char *desc, size_t min_cap_length);
@@ -571,4 +583,10 @@ unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal);
 int tpm2_probe(struct tpm_chip *chip);
 ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip);
 int tpm2_find_cc(struct tpm_chip *chip, u32 cc);
+int tpm2_init_space(struct tpm_space *space);
+void tpm2_del_space(struct tpm_space *space);
+int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
+		       u8 *cmd);
+int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
+		      u32 cc, u8 *buf, size_t bufsiz);
 #endif
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 86565a9..2eadaf7 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -266,7 +266,7 @@ int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 	       sizeof(cmd.params.pcrread_in.pcr_select));
 	cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
 
-	rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
+	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
 			      TPM2_PCR_READ_RESP_BODY_SIZE,
 			      0, "attempting to read a pcr value");
 	if (rc == 0) {
@@ -333,7 +333,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
 		}
 	}
 
-	rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, 0,
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
 			      "attempting extend a PCR value");
 
 	tpm_buf_destroy(&buf);
@@ -382,7 +382,7 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
 		cmd.header.in = tpm2_getrandom_header;
 		cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
 
-		err = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
+		err = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
 				       offsetof(struct tpm2_get_random_out,
 						buffer),
 				       0, "attempting get random");
@@ -441,7 +441,7 @@ void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
 
 	tpm_buf_append_u32(&buf, handle);
 
-	(void) tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, flags,
+	(void) tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, flags,
 				"flushing context");
 
 	tpm_buf_destroy(&buf);
@@ -557,7 +557,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
 		goto out;
 	}
 
-	rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 4, 0,
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, 0,
 			      "sealing data");
 	if (rc)
 		goto out;
@@ -641,7 +641,7 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
 		goto out;
 	}
 
-	rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 4, flags,
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, flags,
 			      "loading blob");
 	if (!rc)
 		*blob_handle = be32_to_cpup(
@@ -693,7 +693,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
 			     options->blobauth /* hmac */,
 			     TPM_DIGEST_SIZE);
 
-	rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 6, flags,
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 6, flags,
 			      "unsealing");
 	if (rc > 0)
 		rc = -EPERM;
@@ -770,7 +770,7 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
 	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
 	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
 
-	rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
+	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
 			      TPM2_GET_TPM_PT_OUT_BODY_SIZE, 0, desc);
 	if (!rc)
 		*value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);
@@ -805,7 +805,7 @@ static int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
 	cmd.header.in = tpm2_startup_header;
 
 	cmd.params.startup_in.startup_type = cpu_to_be16(startup_type);
-	return tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, 0,
+	return tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
 				"attempting to start the TPM");
 }
 
@@ -834,7 +834,7 @@ void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
 	cmd.header.in = tpm2_shutdown_header;
 	cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
 
-	rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, 0,
+	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
 			      "stopping the TPM");
 
 	/* In places where shutdown command is sent there's no much we can do
@@ -898,7 +898,7 @@ static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
 	cmd.header.in = tpm2_selftest_header;
 	cmd.params.selftest_in.full_test = full;
 
-	rc = tpm_transmit_cmd(chip, &cmd, TPM2_SELF_TEST_IN_SIZE, 0, 0,
+	rc = tpm_transmit_cmd(chip, NULL, &cmd, TPM2_SELF_TEST_IN_SIZE, 0, 0,
 			      "continue selftest");
 
 	/* At least some prototype chips seem to give RC_TESTING error
@@ -949,7 +949,8 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
 		cmd.params.pcrread_in.pcr_select[1] = 0x00;
 		cmd.params.pcrread_in.pcr_select[2] = 0x00;
 
-		rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, 0, NULL);
+		rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
+				      NULL);
 		if (rc < 0)
 			break;
 
@@ -982,7 +983,7 @@ int tpm2_probe(struct tpm_chip *chip)
 	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
 	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
 
-	rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, 0, NULL);
+	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0, NULL);
 	if (rc <  0)
 		return rc;
 
@@ -1021,8 +1022,8 @@ static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
 	tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
 	tpm_buf_append_u32(&buf, nr_commands);
 
-	rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 9 + 4 * nr_commands,
-			      0, NULL);
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
+			      9 + 4 * nr_commands, 0, NULL);
 	if (rc) {
 		tpm_buf_destroy(&buf);
 		goto out;
@@ -1134,7 +1135,7 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
 	tpm_buf_append_u32(&buf, 0);
 	tpm_buf_append_u32(&buf, 1);
 
-	rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 9, 0,
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 9, 0,
 			      "get tpm pcr allocation");
 	if (rc)
 		goto out;
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
new file mode 100644
index 0000000..d241c2a
--- /dev/null
+++ b/drivers/char/tpm/tpm2-space.c
@@ -0,0 +1,341 @@
+/*
+ * Copyright (C) 2016 Intel Corporation
+ *
+ * Authors:
+ * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
+ *
+ * Maintained by: <tpmdd-devel@lists.sourceforge.net>
+ *
+ * This file contains TPM2 protocol implementations of the commands
+ * used by the kernel internally.
+ *
+ * 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/gfp.h>
+#include <asm/unaligned.h>
+#include "tpm.h"
+
+enum tpm2_handle_types {
+	TPM2_HT_HMAC_SESSION	= 0x02000000,
+	TPM2_HT_POLICY_SESSION	= 0x03000000,
+	TPM2_HT_TRANSIENT	= 0x80000000,
+};
+
+struct tpm2_context {
+	__be64 sequence;
+	__be32 saved_handle;
+	__be32 hierarchy;
+	__be16 blob_size;
+} __packed;
+
+int tpm2_init_space(struct tpm_space *space)
+{
+	space->context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!space->context_buf)
+		return -ENOMEM;
+
+	return 0;
+}
+
+void tpm2_del_space(struct tpm_space *space)
+{
+	kfree(space->context_buf);
+}
+
+static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
+			     unsigned int *offset, u32 *handle)
+{
+	struct tpm_buf tbuf;
+	struct tpm2_context *ctx;
+	unsigned int body_size;
+	int rc;
+
+	rc = tpm_buf_init(&tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_LOAD);
+	if (rc)
+		return rc;
+
+	ctx = (struct tpm2_context *)&buf[*offset];
+	body_size = sizeof(*ctx) + be16_to_cpu(ctx->blob_size);
+	tpm_buf_append(&tbuf, &buf[*offset], body_size);
+
+	rc = tpm_transmit_cmd(chip, NULL, tbuf.data, PAGE_SIZE, 4,
+			      TPM_TRANSMIT_UNLOCKED, NULL);
+	if (rc < 0) {
+		dev_warn(&chip->dev, "%s: failed with a system error %d\n",
+			 __func__, rc);
+		tpm_buf_destroy(&tbuf);
+		return -EFAULT;
+	} else if (rc > 0) {
+		dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
+			 __func__, rc);
+		tpm_buf_destroy(&tbuf);
+		return -EFAULT;
+	}
+
+	*handle = be32_to_cpup((__be32 *)&tbuf.data[TPM_HEADER_SIZE]);
+	*offset += body_size;
+
+	tpm_buf_destroy(&tbuf);
+	return 0;
+}
+
+static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
+			     unsigned int buf_size, unsigned int *offset)
+{
+	struct tpm_buf tbuf;
+	unsigned int body_size;
+	int rc;
+
+	rc = tpm_buf_init(&tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_SAVE);
+	if (rc)
+		return rc;
+
+	tpm_buf_append_u32(&tbuf, handle);
+
+	rc = tpm_transmit_cmd(chip, NULL, tbuf.data, PAGE_SIZE, 0,
+			      TPM_TRANSMIT_UNLOCKED, NULL);
+	if (rc < 0) {
+		dev_warn(&chip->dev, "%s: failed with a system error %d\n",
+			 __func__, rc);
+		tpm_buf_destroy(&tbuf);
+		return -EFAULT;
+	} else if (tpm2_rc_value(rc) == TPM2_RC_REFERENCE_H0) {
+		tpm_buf_destroy(&tbuf);
+		return -ENOENT;
+	} else if (rc) {
+		dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
+			 __func__, rc);
+		tpm_buf_destroy(&tbuf);
+		return -EFAULT;
+	}
+
+	body_size = tpm_buf_length(&tbuf) - TPM_HEADER_SIZE;
+	if ((*offset + body_size) > buf_size) {
+		dev_warn(&chip->dev, "%s: out of backing storage\n", __func__);
+		tpm_buf_destroy(&tbuf);
+		return -ENOMEM;
+	}
+
+	memcpy(&buf[*offset], &tbuf.data[TPM_HEADER_SIZE], body_size);
+	tpm2_flush_context_cmd(chip, handle, TPM_TRANSMIT_UNLOCKED);
+	*offset += body_size;
+	tpm_buf_destroy(&tbuf);
+	return 0;
+}
+
+static void tpm2_flush_space(struct tpm_chip *chip)
+{
+	struct tpm_space *space = &chip->work_space;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++)
+		if (space->context_tbl[i] && ~space->context_tbl[i])
+			tpm2_flush_context_cmd(chip, space->context_tbl[i],
+					       TPM_TRANSMIT_UNLOCKED);
+}
+
+static int tpm2_load_space(struct tpm_chip *chip)
+{
+	struct tpm_space *space = &chip->work_space;
+	unsigned int offset;
+	int i;
+	int rc;
+
+	for (i = 0, offset = 0; i < ARRAY_SIZE(space->context_tbl); i++) {
+		if (!space->context_tbl[i])
+			continue;
+
+		/* sanity check, should never happen */
+		if (~space->context_tbl[i]) {
+			dev_err(&chip->dev, "context table is inconsistent");
+			return -EFAULT;
+		}
+
+		rc = tpm2_load_context(chip, space->context_buf, &offset,
+				       &space->context_tbl[i]);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+static int tpm2_map_to_phandle(struct tpm_space *space, void *handle)
+{
+	u32 vhandle;
+	u32 phandle;
+	int i;
+
+	vhandle = be32_to_cpup((__be32 *)handle);
+	if ((vhandle & 0xFF000000) != TPM2_HT_TRANSIENT)
+		return 0;
+
+	i = 0xFFFFFF - (vhandle & 0xFFFFFF);
+	if (i > ARRAY_SIZE(space->context_tbl) || !space->context_tbl[i])
+		return -EINVAL;
+
+	phandle = space->context_tbl[i];
+	*((__be32 *)handle) = cpu_to_be32(phandle);
+
+	return 0;
+}
+
+static int tpm2_map_command(struct tpm_chip *chip, u32 cc, u8 *cmd)
+{
+	struct tpm_space *space = &chip->work_space;
+	unsigned int nr_handles;
+	u32 attrs;
+	u32 *handle;
+	int i;
+	int rc;
+
+	i = tpm2_find_cc(chip, cc);
+	if (i < 0)
+		return -EINVAL;
+
+	attrs = chip->cc_attrs_tbl[i];
+	nr_handles = (attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0);
+
+	handle = (u32 *)&cmd[TPM_HEADER_SIZE];
+	for (i = 0; i < nr_handles; i++, handle++) {
+		rc = tpm2_map_to_phandle(space, handle);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
+		       u8 *cmd)
+{
+	int rc;
+
+	if (!space)
+		return 0;
+
+	memcpy(&chip->work_space.context_tbl, &space->context_tbl,
+	       sizeof(space->context_tbl));
+	memcpy(chip->work_space.context_buf, space->context_buf, PAGE_SIZE);
+
+	rc = tpm2_load_space(chip);
+	if (rc) {
+		tpm2_flush_space(chip);
+		return rc;
+	}
+
+	rc = tpm2_map_command(chip, cc, cmd);
+	if (rc) {
+		tpm2_flush_space(chip);
+		return rc;
+	}
+
+	return 0;
+}
+
+static int tpm2_map_response(struct tpm_chip *chip, u32 cc, u8 *rsp, size_t len)
+{
+	struct tpm_space *space = &chip->work_space;
+	u32 phandle;
+	u32 vhandle;
+	u32 attrs;
+	u32 return_code = get_unaligned_be32((__be32 *)&rsp[6]);
+	int i;
+
+	if (return_code != TPM2_RC_SUCCESS)
+		return 0;
+
+	i = tpm2_find_cc(chip, cc);
+	/* sanity check, should never happen */
+	if (i < 0)
+		return -EFAULT;
+
+	attrs = chip->cc_attrs_tbl[i];
+	if (!((attrs >> TPM2_CC_ATTR_RHANDLE) & 1))
+		return 0;
+
+	phandle = be32_to_cpup((__be32 *)&rsp[TPM_HEADER_SIZE]);
+	if ((phandle & 0xFF000000) != TPM2_HT_TRANSIENT)
+		return 0;
+
+	/* Garbage collect a dead context. */
+	for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++) {
+		if (space->context_tbl[i] == phandle) {
+			space->context_tbl[i] = 0;
+			break;
+		}
+	}
+
+	for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++)
+		if (!space->context_tbl[i])
+			break;
+
+	if (i == ARRAY_SIZE(space->context_tbl)) {
+		dev_warn(&chip->dev, "%s: out of context slots\n", __func__);
+		tpm2_flush_context_cmd(chip, phandle, TPM_TRANSMIT_UNLOCKED);
+		return -ENOMEM;
+	}
+
+	space->context_tbl[i] = phandle;
+	vhandle = TPM2_HT_TRANSIENT | (0xFFFFFF - i);
+	*(__be32 *)&rsp[TPM_HEADER_SIZE] = cpu_to_be32(vhandle);
+
+	return 0;
+}
+
+static int tpm2_save_space(struct tpm_chip *chip)
+{
+	struct tpm_space *space = &chip->work_space;
+	unsigned int offset;
+	int i;
+	int rc;
+
+	for (i = 0, offset = 0; i < ARRAY_SIZE(space->context_tbl); i++) {
+		if (!(space->context_tbl[i] && ~space->context_tbl[i]))
+			continue;
+
+		rc = tpm2_save_context(chip, space->context_tbl[i],
+				       space->context_buf, PAGE_SIZE,
+				       &offset);
+		if (rc == -ENOENT) {
+			space->context_tbl[i] = 0;
+			continue;
+		} else if (rc)
+			return rc;
+
+		space->context_tbl[i] = ~0;
+	}
+
+	return 0;
+}
+
+int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
+		      u32 cc, u8 *buf, size_t bufsiz)
+{
+	int rc;
+
+	if (!space)
+		return 0;
+
+	rc = tpm2_map_response(chip, cc, buf, bufsiz);
+	if (rc) {
+		tpm2_flush_space(chip);
+		return rc;
+	}
+
+	rc = tpm2_save_space(chip);
+	if (rc) {
+		tpm2_flush_space(chip);
+		return rc;
+	}
+
+	memcpy(&space->context_tbl, &chip->work_space.context_tbl,
+	       sizeof(space->context_tbl));
+	memcpy(space->context_buf, chip->work_space.context_buf, PAGE_SIZE);
+
+	return 0;
+}
-- 
2.9.3

[PATCH 4/6] tpm: split out tpm-dev.c into tpm-dev.c and tpm-common-dev.c

[Jarkko Sakkinen]

From: James Bottomley <James.Bottomley@HansenPartnership.com>

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/char/tpm/Makefile         |   2 +-
 drivers/char/tpm/tpm-dev-common.c | 148 ++++++++++++++++++++++++++++++++++++++
 drivers/char/tpm/tpm-dev.c        | 143 ++++--------------------------------
 drivers/char/tpm/tpm-dev.h        |  27 +++++++
 4 files changed, 190 insertions(+), 130 deletions(-)
 create mode 100644 drivers/char/tpm/tpm-dev-common.c
 create mode 100644 drivers/char/tpm/tpm-dev.h

diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index 8f07fcf..10e5827 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -3,7 +3,7 @@
 #
 obj-$(CONFIG_TCG_TPM) += tpm.o
 tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
-	 tpm1_eventlog.o tpm2_eventlog.o tpm2-space.o
+	 tpm-dev-common.o tpm1_eventlog.o tpm2_eventlog.o tpm2-space.o
 tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
 tpm-$(CONFIG_OF) += tpm_of.o
 obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
new file mode 100644
index 0000000..610638a
--- /dev/null
+++ b/drivers/char/tpm/tpm-dev-common.c
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2004 IBM Corporation
+ * Authors:
+ * Leendert van Doorn <leendert@watson.ibm.com>
+ * Dave Safford <safford@watson.ibm.com>
+ * Reiner Sailer <sailer@watson.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.com>
+ *
+ * Copyright (C) 2013 Obsidian Research Corp
+ * Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
+ *
+ * Device file system 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/slab.h>
+#include <linux/uaccess.h>
+#include "tpm.h"
+#include "tpm-dev.h"
+
+static void user_reader_timeout(unsigned long ptr)
+{
+	struct file_priv *priv = (struct file_priv *)ptr;
+
+	pr_warn("TPM user space timeout is deprecated (pid=%d)\n",
+		task_tgid_nr(current));
+
+	schedule_work(&priv->work);
+}
+
+static void timeout_work(struct work_struct *work)
+{
+	struct file_priv *priv = container_of(work, struct file_priv, work);
+
+	mutex_lock(&priv->buffer_mutex);
+	atomic_set(&priv->data_pending, 0);
+	memset(priv->data_buffer, 0, sizeof(priv->data_buffer));
+	mutex_unlock(&priv->buffer_mutex);
+}
+
+void tpm_common_open(struct file *file, struct tpm_chip *chip,
+		     struct file_priv *priv)
+{
+	priv->chip = chip;
+	atomic_set(&priv->data_pending, 0);
+	mutex_init(&priv->buffer_mutex);
+	setup_timer(&priv->user_read_timer, user_reader_timeout,
+			(unsigned long)priv);
+	INIT_WORK(&priv->work, timeout_work);
+
+	file->private_data = priv;
+}
+
+ssize_t tpm_common_read(struct file *file, char __user *buf,
+			size_t size, loff_t *off)
+{
+	struct file_priv *priv = file->private_data;
+	ssize_t ret_size;
+	ssize_t orig_ret_size;
+	int rc;
+
+	del_singleshot_timer_sync(&priv->user_read_timer);
+	flush_work(&priv->work);
+	ret_size = atomic_read(&priv->data_pending);
+	if (ret_size > 0) {	/* relay data */
+		orig_ret_size = ret_size;
+		if (size < ret_size)
+			ret_size = size;
+
+		mutex_lock(&priv->buffer_mutex);
+		rc = copy_to_user(buf, priv->data_buffer, ret_size);
+		memset(priv->data_buffer, 0, orig_ret_size);
+		if (rc)
+			ret_size = -EFAULT;
+
+		mutex_unlock(&priv->buffer_mutex);
+	}
+
+	atomic_set(&priv->data_pending, 0);
+
+	return ret_size;
+}
+
+ssize_t tpm_common_write(struct file *file, const char __user *buf,
+			 size_t size, loff_t *off, struct tpm_space *space)
+{
+	struct file_priv *priv = file->private_data;
+	size_t in_size = size;
+	ssize_t out_size;
+
+	/* Cannot perform a write until the read has cleared either via
+	 * tpm_read or a user_read_timer timeout. This also prevents split
+	 * buffered writes from blocking here.
+	 */
+	if (atomic_read(&priv->data_pending) != 0)
+		return -EBUSY;
+
+	if (in_size > TPM_BUFSIZE)
+		return -E2BIG;
+
+	mutex_lock(&priv->buffer_mutex);
+
+	if (copy_from_user
+	    (priv->data_buffer, (void __user *) buf, in_size)) {
+		mutex_unlock(&priv->buffer_mutex);
+		return -EFAULT;
+	}
+
+	/* atomic tpm command send and result receive. We only hold the ops
+	 * lock during this period so that the tpm can be unregistered even if
+	 * the char dev is held open.
+	 */
+	if (tpm_try_get_ops(priv->chip)) {
+		mutex_unlock(&priv->buffer_mutex);
+		return -EPIPE;
+	}
+	out_size = tpm_transmit(priv->chip, space, priv->data_buffer,
+				sizeof(priv->data_buffer), 0);
+
+	tpm_put_ops(priv->chip);
+	if (out_size < 0) {
+		mutex_unlock(&priv->buffer_mutex);
+		return out_size;
+	}
+
+	atomic_set(&priv->data_pending, out_size);
+	mutex_unlock(&priv->buffer_mutex);
+
+	/* Set a timeout by which the reader must come claim the result */
+	mod_timer(&priv->user_read_timer, jiffies + (120 * HZ));
+
+	return in_size;
+}
+
+/*
+ * Called on file close
+ */
+void tpm_common_release(struct file *file, struct file_priv *priv)
+{
+	del_singleshot_timer_sync(&priv->user_read_timer);
+	flush_work(&priv->work);
+	file->private_data = NULL;
+	atomic_set(&priv->data_pending, 0);
+}
diff --git a/drivers/char/tpm/tpm-dev.c b/drivers/char/tpm/tpm-dev.c
index 414553b..ebd74ab 100644
--- a/drivers/char/tpm/tpm-dev.c
+++ b/drivers/char/tpm/tpm-dev.c
@@ -18,48 +18,15 @@
  *
  */
 #include <linux/slab.h>
-#include <linux/uaccess.h>
-#include "tpm.h"
-
-struct file_priv {
-	struct tpm_chip *chip;
-
-	/* Data passed to and from the tpm via the read/write calls */
-	atomic_t data_pending;
-	struct mutex buffer_mutex;
-
-	struct timer_list user_read_timer;      /* user needs to claim result */
-	struct work_struct work;
-
-	u8 data_buffer[TPM_BUFSIZE];
-};
-
-static void user_reader_timeout(unsigned long ptr)
-{
-	struct file_priv *priv = (struct file_priv *)ptr;
-
-	pr_warn("TPM user space timeout is deprecated (pid=%d)\n",
-		task_tgid_nr(current));
-
-	schedule_work(&priv->work);
-}
-
-static void timeout_work(struct work_struct *work)
-{
-	struct file_priv *priv = container_of(work, struct file_priv, work);
-
-	mutex_lock(&priv->buffer_mutex);
-	atomic_set(&priv->data_pending, 0);
-	memset(priv->data_buffer, 0, sizeof(priv->data_buffer));
-	mutex_unlock(&priv->buffer_mutex);
-}
+#include "tpm-dev.h"
 
 static int tpm_open(struct inode *inode, struct file *file)
 {
-	struct tpm_chip *chip =
-		container_of(inode->i_cdev, struct tpm_chip, cdev);
+	struct tpm_chip *chip;
 	struct file_priv *priv;
 
+	chip = container_of(inode->i_cdev, struct tpm_chip, cdev);
+
 	/* It's assured that the chip will be opened just once,
 	 * by the check of is_open variable, which is protected
 	 * by driver_lock. */
@@ -69,100 +36,22 @@ static int tpm_open(struct inode *inode, struct file *file)
 	}
 
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
-	if (priv == NULL) {
-		clear_bit(0, &chip->is_open);
-		return -ENOMEM;
-	}
+	if (priv == NULL)
+		goto out;
 
-	priv->chip = chip;
-	atomic_set(&priv->data_pending, 0);
-	mutex_init(&priv->buffer_mutex);
-	setup_timer(&priv->user_read_timer, user_reader_timeout,
-			(unsigned long)priv);
-	INIT_WORK(&priv->work, timeout_work);
+	tpm_common_open(file, chip, priv);
 
-	file->private_data = priv;
 	return 0;
-}
-
-static ssize_t tpm_read(struct file *file, char __user *buf,
-			size_t size, loff_t *off)
-{
-	struct file_priv *priv = file->private_data;
-	ssize_t ret_size;
-	int rc;
 
-	del_singleshot_timer_sync(&priv->user_read_timer);
-	flush_work(&priv->work);
-	ret_size = atomic_read(&priv->data_pending);
-	if (ret_size > 0) {	/* relay data */
-		ssize_t orig_ret_size = ret_size;
-		if (size < ret_size)
-			ret_size = size;
-
-		mutex_lock(&priv->buffer_mutex);
-		rc = copy_to_user(buf, priv->data_buffer, ret_size);
-		memset(priv->data_buffer, 0, orig_ret_size);
-		if (rc)
-			ret_size = -EFAULT;
-
-		mutex_unlock(&priv->buffer_mutex);
-	}
-
-	atomic_set(&priv->data_pending, 0);
-
-	return ret_size;
+ out:
+	clear_bit(0, &chip->is_open);
+	return -ENOMEM;
 }
 
 static ssize_t tpm_write(struct file *file, const char __user *buf,
 			 size_t size, loff_t *off)
 {
-	struct file_priv *priv = file->private_data;
-	size_t in_size = size;
-	ssize_t out_size;
-
-	/* cannot perform a write until the read has cleared
-	   either via tpm_read or a user_read_timer timeout.
-	   This also prevents splitted buffered writes from blocking here.
-	*/
-	if (atomic_read(&priv->data_pending) != 0)
-		return -EBUSY;
-
-	if (in_size > TPM_BUFSIZE)
-		return -E2BIG;
-
-	mutex_lock(&priv->buffer_mutex);
-
-	if (copy_from_user
-	    (priv->data_buffer, (void __user *) buf, in_size)) {
-		mutex_unlock(&priv->buffer_mutex);
-		return -EFAULT;
-	}
-
-	/* atomic tpm command send and result receive. We only hold the ops
-	 * lock during this period so that the tpm can be unregistered even if
-	 * the char dev is held open.
-	 */
-	if (tpm_try_get_ops(priv->chip)) {
-		mutex_unlock(&priv->buffer_mutex);
-		return -EPIPE;
-	}
-	out_size = tpm_transmit(priv->chip, NULL, priv->data_buffer,
-				sizeof(priv->data_buffer), 0);
-
-	tpm_put_ops(priv->chip);
-	if (out_size < 0) {
-		mutex_unlock(&priv->buffer_mutex);
-		return out_size;
-	}
-
-	atomic_set(&priv->data_pending, out_size);
-	mutex_unlock(&priv->buffer_mutex);
-
-	/* Set a timeout by which the reader must come claim the result */
-	mod_timer(&priv->user_read_timer, jiffies + (120 * HZ));
-
-	return in_size;
+	return tpm_common_write(file, buf, size, off, NULL);
 }
 
 /*
@@ -172,12 +61,10 @@ static int tpm_release(struct inode *inode, struct file *file)
 {
 	struct file_priv *priv = file->private_data;
 
-	del_singleshot_timer_sync(&priv->user_read_timer);
-	flush_work(&priv->work);
-	file->private_data = NULL;
-	atomic_set(&priv->data_pending, 0);
+	tpm_common_release(file, priv);
 	clear_bit(0, &priv->chip->is_open);
 	kfree(priv);
+
 	return 0;
 }
 
@@ -185,9 +72,7 @@ const struct file_operations tpm_fops = {
 	.owner = THIS_MODULE,
 	.llseek = no_llseek,
 	.open = tpm_open,
-	.read = tpm_read,
+	.read = tpm_common_read,
 	.write = tpm_write,
 	.release = tpm_release,
 };
-
-
diff --git a/drivers/char/tpm/tpm-dev.h b/drivers/char/tpm/tpm-dev.h
new file mode 100644
index 0000000..ff15cf7
--- /dev/null
+++ b/drivers/char/tpm/tpm-dev.h
@@ -0,0 +1,27 @@
+#ifndef _TPM_DEV_H
+#define _TPM_DEV_H
+
+#include "tpm.h"
+
+struct file_priv {
+	struct tpm_chip *chip;
+
+	/* Data passed to and from the tpm via the read/write calls */
+	atomic_t data_pending;
+	struct mutex buffer_mutex;
+
+	struct timer_list user_read_timer;      /* user needs to claim result */
+	struct work_struct work;
+
+	u8 data_buffer[TPM_BUFSIZE];
+};
+
+void tpm_common_open(struct file *file, struct tpm_chip *chip,
+		     struct file_priv *priv);
+ssize_t tpm_common_read(struct file *file, char __user *buf,
+			size_t size, loff_t *off);
+ssize_t tpm_common_write(struct file *file, const char __user *buf,
+			 size_t size, loff_t *off, struct tpm_space *space);
+void tpm_common_release(struct file *file, struct file_priv *priv);
+
+#endif
-- 
2.9.3

[PATCH 5/6] tpm: expose spaces via a device link /dev/tpms<n>

[Jarkko Sakkinen]

From: James Bottomley <James.Bottomley@HansenPartnership.com>

Currently the tpm spaces are not exposed to userspace.  Make this
exposure via a separate device, which can now be opened multiple times
because each read/write transaction goes separately via the space.

Concurrency is protected by the chip->tpm_mutex for each read/write
transaction separately.  The TPM is cleared of all transient objects
by the time the mutex is dropped, so there should be no interference
between the kernel and userspace.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/char/tpm/Makefile        |  3 +-
 drivers/char/tpm/tpm-chip.c      | 73 ++++++++++++++++++++++++++++++++++++++--
 drivers/char/tpm/tpm-interface.c | 13 +++++--
 drivers/char/tpm/tpm.h           |  4 +++
 drivers/char/tpm/tpms-dev.c      | 65 +++++++++++++++++++++++++++++++++++
 5 files changed, 152 insertions(+), 6 deletions(-)
 create mode 100644 drivers/char/tpm/tpms-dev.c

diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index 10e5827..bbe6531 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -3,7 +3,8 @@
 #
 obj-$(CONFIG_TCG_TPM) += tpm.o
 tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
-	 tpm-dev-common.o tpm1_eventlog.o tpm2_eventlog.o tpm2-space.o
+	 tpm-dev-common.o tpms-dev.o tpm1_eventlog.o tpm2_eventlog.o \
+         tpm2-space.o
 tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
 tpm-$(CONFIG_OF) += tpm_of.o
 obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 993b9ae..c71c353 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -33,6 +33,7 @@ DEFINE_IDR(dev_nums_idr);
 static DEFINE_MUTEX(idr_lock);
 
 struct class *tpm_class;
+struct class *tpms_class;
 dev_t tpm_devt;
 
 /**
@@ -132,6 +133,14 @@ static void tpm_dev_release(struct device *dev)
 	kfree(chip);
 }
 
+static void tpm_devs_release(struct device *dev)
+{
+	struct tpm_chip *chip = container_of(dev, struct tpm_chip, devs);
+
+	/* release the master device reference */
+	put_device(&chip->dev);
+}
+
 /**
  * tpm_chip_alloc() - allocate a new struct tpm_chip instance
  * @pdev: device to which the chip is associated
@@ -168,27 +177,47 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
 	chip->dev_num = rc;
 
 	device_initialize(&chip->dev);
+	device_initialize(&chip->devs);
 
 	chip->dev.class = tpm_class;
 	chip->dev.release = tpm_dev_release;
 	chip->dev.parent = pdev;
 	chip->dev.groups = chip->groups;
 
+	chip->devs.parent = pdev;
+	chip->devs.class = tpms_class;
+	chip->devs.release = tpm_devs_release;
+	/* get extra reference on main device to hold on
+	 * behalf of devs.  This holds the chip structure
+	 * while cdevs is in use.  The corresponding put
+	 * is in the tpm_devs_release
+	 */
+	get_device(&chip->dev);
+
 	if (chip->dev_num == 0)
 		chip->dev.devt = MKDEV(MISC_MAJOR, TPM_MINOR);
 	else
 		chip->dev.devt = MKDEV(MAJOR(tpm_devt), chip->dev_num);
 
+	chip->devs.devt =
+		MKDEV(MAJOR(tpm_devt), chip->dev_num + TPM_NUM_DEVICES);
+
 	rc = dev_set_name(&chip->dev, "tpm%d", chip->dev_num);
 	if (rc)
 		goto out;
+	rc = dev_set_name(&chip->devs, "tpms%d", chip->dev_num);
+	if (rc)
+		goto out;
 
 	if (!pdev)
 		chip->flags |= TPM_CHIP_FLAG_VIRTUAL;
 
 	cdev_init(&chip->cdev, &tpm_fops);
+	cdev_init(&chip->cdevs, &tpms_fops);
 	chip->cdev.owner = THIS_MODULE;
+	chip->cdevs.owner = THIS_MODULE;
 	chip->cdev.kobj.parent = &chip->dev.kobj;
+	chip->cdevs.kobj.parent = &chip->devs.kobj;
 
 	chip->work_space.context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!chip->work_space.context_buf) {
@@ -199,6 +228,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
 	return chip;
 
 out:
+	put_device(&chip->devs);
 	put_device(&chip->dev);
 	return ERR_PTR(rc);
 }
@@ -244,7 +274,7 @@ static int tpm_add_char_device(struct tpm_chip *chip)
 			dev_name(&chip->dev), MAJOR(chip->dev.devt),
 			MINOR(chip->dev.devt), rc);
 
-		return rc;
+		goto err_1;
 	}
 
 	rc = device_add(&chip->dev);
@@ -254,16 +284,44 @@ static int tpm_add_char_device(struct tpm_chip *chip)
 			dev_name(&chip->dev), MAJOR(chip->dev.devt),
 			MINOR(chip->dev.devt), rc);
 
-		cdev_del(&chip->cdev);
-		return rc;
+		goto err_2;
+	}
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		rc = cdev_add(&chip->cdevs, chip->devs.devt, 1);
+	if (rc) {
+		dev_err(&chip->dev,
+			"unable to cdev_add() %s, major %d, minor %d, err=%d\n",
+			dev_name(&chip->devs), MAJOR(chip->devs.devt),
+			MINOR(chip->devs.devt), rc);
+
+		goto err_3;
 	}
 
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		rc = device_add(&chip->devs);
+	if (rc) {
+		dev_err(&chip->dev,
+			"unable to device_register() %s, major %d, minor %d, err=%d\n",
+			dev_name(&chip->devs), MAJOR(chip->devs.devt),
+			MINOR(chip->devs.devt), rc);
+
+		goto err_4;
+	}
 	/* Make the chip available. */
 	mutex_lock(&idr_lock);
 	idr_replace(&dev_nums_idr, chip, chip->dev_num);
 	mutex_unlock(&idr_lock);
 
 	return rc;
+ err_4:
+	cdev_del(&chip->cdevs);
+ err_3:
+	device_del(&chip->dev);
+ err_2:
+	cdev_del(&chip->cdev);
+ err_1:
+	return rc;
 }
 
 static void tpm_del_char_device(struct tpm_chip *chip)
@@ -271,6 +329,11 @@ static void tpm_del_char_device(struct tpm_chip *chip)
 	cdev_del(&chip->cdev);
 	device_del(&chip->dev);
 
+	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+		cdev_del(&chip->cdevs);
+		device_del(&chip->devs);
+	}
+
 	/* Make the chip unavailable. */
 	mutex_lock(&idr_lock);
 	idr_replace(&dev_nums_idr, NULL, chip->dev_num);
@@ -282,6 +345,10 @@ static void tpm_del_char_device(struct tpm_chip *chip)
 		tpm2_shutdown(chip, TPM2_SU_CLEAR);
 	chip->ops = NULL;
 	up_write(&chip->ops_sem);
+	/* will release the devs reference to the chip->dev unless
+	 * something has cdevs open
+	 */
+	put_device(&chip->devs);
 }
 
 static void tpm_del_legacy_sysfs(struct tpm_chip *chip)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 7e1b557..ae09570 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -1254,9 +1254,17 @@ static int __init tpm_init(void)
 		return PTR_ERR(tpm_class);
 	}
 
-	rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm");
+	tpms_class = class_create(THIS_MODULE, "tpms");
+	if (IS_ERR(tpms_class)) {
+		pr_err("couldn't create tpms class\n");
+		class_destroy(tpm_class);
+		return PTR_ERR(tpms_class);
+	}
+
+	rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm");
 	if (rc < 0) {
 		pr_err("tpm: failed to allocate char dev region\n");
+		class_destroy(tpms_class);
 		class_destroy(tpm_class);
 		return rc;
 	}
@@ -1268,7 +1276,8 @@ static void __exit tpm_exit(void)
 {
 	idr_destroy(&dev_nums_idr);
 	class_destroy(tpm_class);
-	unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES);
+	class_destroy(tpms_class);
+	unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES);
 }
 
 subsys_initcall(tpm_init);
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index ba10973..8670cc5 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -181,7 +181,9 @@ struct tpm_chip_seqops {
 
 struct tpm_chip {
 	struct device dev;
+	struct device devs;
 	struct cdev cdev;
+	struct cdev cdevs;
 
 	/* A driver callback under ops cannot be run unless ops_sem is held
 	 * (sometimes implicitly, eg for the sysfs code). ops becomes null
@@ -509,8 +511,10 @@ static inline void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
 }
 
 extern struct class *tpm_class;
+extern struct class *tpms_class;
 extern dev_t tpm_devt;
 extern const struct file_operations tpm_fops;
+extern const struct file_operations tpms_fops;
 extern struct idr dev_nums_idr;
 
 enum tpm_transmit_flags {
diff --git a/drivers/char/tpm/tpms-dev.c b/drivers/char/tpm/tpms-dev.c
new file mode 100644
index 0000000..5720885
--- /dev/null
+++ b/drivers/char/tpm/tpms-dev.c
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2017 James.Bottomley@HansenPartnership.com
+ *
+ * GPLv2
+ */
+#include <linux/slab.h>
+#include "tpm-dev.h"
+
+struct tpms_priv {
+	struct file_priv priv;
+	struct tpm_space space;
+};
+
+static int tpms_open(struct inode *inode, struct file *file)
+{
+	struct tpm_chip *chip;
+	struct tpms_priv *priv;
+	int rc;
+
+	chip = container_of(inode->i_cdev, struct tpm_chip, cdevs);
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (priv == NULL)
+		return -ENOMEM;
+
+	rc = tpm2_init_space(&priv->space);
+	if (rc) {
+		kfree(priv);
+		return -ENOMEM;
+	}
+
+	tpm_common_open(file, chip, &priv->priv);
+
+	return 0;
+}
+
+static int tpms_release(struct inode *inode, struct file *file)
+{
+	struct file_priv *fpriv = file->private_data;
+	struct tpms_priv *priv = container_of(fpriv, struct tpms_priv, priv);
+
+	tpm_common_release(file, fpriv);
+	tpm2_del_space(&priv->space);
+	kfree(priv);
+
+	return 0;
+}
+
+ssize_t tpms_write(struct file *file, const char __user *buf,
+		   size_t size, loff_t *off)
+{
+	struct file_priv *fpriv = file->private_data;
+	struct tpms_priv *priv = container_of(fpriv, struct tpms_priv, priv);
+
+	return tpm_common_write(file, buf, size, off, &priv->space);
+}
+
+const struct file_operations tpms_fops = {
+	.owner = THIS_MODULE,
+	.llseek = no_llseek,
+	.open = tpms_open,
+	.read = tpm_common_read,
+	.write = tpms_write,
+	.release = tpms_release,
+};
+
-- 
2.9.3

[PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

[Jarkko Sakkinen]

From: James Bottomley <James.Bottomley@HansenPartnership.com>

Sessions are different from transient objects in that their handles
may not be virtualized (because they're used for some hmac
calculations).  Additionally when a session is context saved, a
vestigial memory remains in the TPM and if it is also flushed, that
will be lost and the session context will refuse to load next time, so
the code is updated to flush only transient objects after a context
save.  Add a separate array (chip->session_tbl) to save and restore
sessions by handle.  Use the failure of a context save or load to
signal that the session has been flushed from the TPM and we can
remove its memory from chip->session_tbl.

Sessions are also isolated during each instance of a tpm space.  This
means that spaces shouldn't be able to see each other's sessions and
is enforced by ensuring that a space user may only refer to sessions
handles that are present in their own chip->session_tbl.  Finally when
a space is closed, all the sessions belonging to it should be flushed
so the handles may be re-used by other spaces.

Note that if we get a session save or load error, all sessions are
effectively flushed.  Even though we restore the session buffer, all
the old sessions will refuse to load after the flush and they'll be
purged from our session memory.  This means that while transient
context handling is still soft in the face of errors, session handling
is hard (any failure of the model means all sessions are lost).

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/char/tpm/tpm-chip.c   |   6 +++
 drivers/char/tpm/tpm.h        |   4 +-
 drivers/char/tpm/tpm2-space.c | 115 ++++++++++++++++++++++++++++++++++++++++--
 drivers/char/tpm/tpms-dev.c   |   2 +-
 4 files changed, 122 insertions(+), 5 deletions(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index c71c353..e8536ab 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -130,6 +130,7 @@ static void tpm_dev_release(struct device *dev)
 
 	kfree(chip->log.bios_event_log);
 	kfree(chip->work_space.context_buf);
+	kfree(chip->work_space.session_buf);
 	kfree(chip);
 }
 
@@ -224,6 +225,11 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
 		rc = -ENOMEM;
 		goto out;
 	}
+	chip->work_space.session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!chip->work_space.session_buf) {
+		rc = -ENOMEM;
+		goto out;
+	}
 
 	return chip;
 
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 8670cc5..9261223 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -160,6 +160,8 @@ enum tpm2_cc_attrs {
 struct tpm_space {
 	u32 context_tbl[3];
 	u8 *context_buf;
+	u32 session_tbl[3];
+	u8 *session_buf;
 };
 
 enum tpm_chip_flags {
@@ -588,7 +590,7 @@ int tpm2_probe(struct tpm_chip *chip);
 ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip);
 int tpm2_find_cc(struct tpm_chip *chip, u32 cc);
 int tpm2_init_space(struct tpm_space *space);
-void tpm2_del_space(struct tpm_space *space);
+void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space);
 int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
 		       u8 *cmd);
 int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index d241c2a..fb817ca 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -32,18 +32,39 @@ struct tpm2_context {
 	__be16 blob_size;
 } __packed;
 
+static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++) {
+		if (space->session_tbl[i])
+			tpm2_flush_context_cmd(chip, space->session_tbl[i],
+					       TPM_TRANSMIT_UNLOCKED);
+	}
+}
+
 int tpm2_init_space(struct tpm_space *space)
 {
 	space->context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!space->context_buf)
 		return -ENOMEM;
 
+	space->session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	if (space->session_buf == NULL) {
+		kfree(space->context_buf);
+		return -ENOMEM;
+	}
+
 	return 0;
 }
 
-void tpm2_del_space(struct tpm_space *space)
+void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space)
 {
+	mutex_lock(&chip->tpm_mutex);
+	tpm2_flush_sessions(chip, space);
+	mutex_unlock(&chip->tpm_mutex);
 	kfree(space->context_buf);
+	kfree(space->session_buf);
 }
 
 static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
@@ -69,6 +90,20 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
 			 __func__, rc);
 		tpm_buf_destroy(&tbuf);
 		return -EFAULT;
+	} else if (tpm2_rc_value(rc) == TPM2_RC_HANDLE ||
+		   rc == TPM2_RC_REFERENCE_H0) {
+		/*
+		 * TPM_RC_HANDLE means that the session context can't
+		 * be loaded because of an internal counter mismatch
+		 * that makes the TPM think there might have been a
+		 * replay.  This might happen if the context was saved
+		 * and loaded outside the space.
+		 *
+		 * TPM_RC_REFERENCE_H0 means the session has been
+		 * flushed outside the space
+		 */
+		rc = -ENOENT;
+		tpm_buf_destroy(&tbuf);
 	} else if (rc > 0) {
 		dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
 			 __func__, rc);
@@ -121,12 +156,30 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
 	}
 
 	memcpy(&buf[*offset], &tbuf.data[TPM_HEADER_SIZE], body_size);
-	tpm2_flush_context_cmd(chip, handle, TPM_TRANSMIT_UNLOCKED);
 	*offset += body_size;
 	tpm_buf_destroy(&tbuf);
 	return 0;
 }
 
+static int tpm2_session_add(struct tpm_chip *chip, u32 handle)
+{
+	struct tpm_space *space = &chip->work_space;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++)
+		if (space->session_tbl[i] == 0)
+			break;
+	if (i == ARRAY_SIZE(space->session_tbl)) {
+		dev_err(&chip->dev, "out of session slots\n");
+		tpm2_flush_context_cmd(chip, handle, TPM_TRANSMIT_UNLOCKED);
+		return -ENOMEM;
+	}
+
+	space->session_tbl[i] = handle;
+
+	return 0;
+}
+
 static void tpm2_flush_space(struct tpm_chip *chip)
 {
 	struct tpm_space *space = &chip->work_space;
@@ -136,6 +189,8 @@ static void tpm2_flush_space(struct tpm_chip *chip)
 		if (space->context_tbl[i] && ~space->context_tbl[i])
 			tpm2_flush_context_cmd(chip, space->context_tbl[i],
 					       TPM_TRANSMIT_UNLOCKED);
+
+	tpm2_flush_sessions(chip, space);
 }
 
 static int tpm2_load_space(struct tpm_chip *chip)
@@ -161,6 +216,28 @@ static int tpm2_load_space(struct tpm_chip *chip)
 			return rc;
 	}
 
+	for (i = 0, offset = 0; i < ARRAY_SIZE(space->session_tbl); i++) {
+		u32 handle;
+
+		if (!space->session_tbl[i])
+			continue;
+
+		rc = tpm2_load_context(chip, space->session_buf,
+				       &offset, &handle);
+		if (rc == -ENOENT) {
+			/* load failed, just forget session */
+			space->session_tbl[i] = 0;
+		} else if (rc) {
+			tpm2_flush_space(chip);
+			return rc;
+		}
+		if (handle != space->session_tbl[i]) {
+			dev_warn(&chip->dev, "session restored to wrong handle\n");
+			tpm2_flush_space(chip);
+			return -EFAULT;
+		}
+	}
+
 	return 0;
 }
 
@@ -220,7 +297,10 @@ int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
 
 	memcpy(&chip->work_space.context_tbl, &space->context_tbl,
 	       sizeof(space->context_tbl));
+	memcpy(&chip->work_space.session_tbl, &space->session_tbl,
+	       sizeof(space->session_tbl));
 	memcpy(chip->work_space.context_buf, space->context_buf, PAGE_SIZE);
+	memcpy(chip->work_space.session_buf, space->session_buf, PAGE_SIZE);
 
 	rc = tpm2_load_space(chip);
 	if (rc) {
@@ -241,6 +321,7 @@ static int tpm2_map_response(struct tpm_chip *chip, u32 cc, u8 *rsp, size_t len)
 {
 	struct tpm_space *space = &chip->work_space;
 	u32 phandle;
+	u32 phandle_type;
 	u32 vhandle;
 	u32 attrs;
 	u32 return_code = get_unaligned_be32((__be32 *)&rsp[6]);
@@ -259,9 +340,15 @@ static int tpm2_map_response(struct tpm_chip *chip, u32 cc, u8 *rsp, size_t len)
 		return 0;
 
 	phandle = be32_to_cpup((__be32 *)&rsp[TPM_HEADER_SIZE]);
-	if ((phandle & 0xFF000000) != TPM2_HT_TRANSIENT)
+	phandle_type = (phandle & 0xFF000000);
+	if (phandle_type != TPM2_HT_TRANSIENT &&
+	    phandle_type != TPM2_HT_HMAC_SESSION &&
+	    phandle_type != TPM2_HT_POLICY_SESSION)
 		return 0;
 
+	if (phandle_type != TPM2_HT_TRANSIENT)
+		return tpm2_session_add(chip, phandle);
+
 	/* Garbage collect a dead context. */
 	for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++) {
 		if (space->context_tbl[i] == phandle) {
@@ -307,9 +394,28 @@ static int tpm2_save_space(struct tpm_chip *chip)
 		} else if (rc)
 			return rc;
 
+		tpm2_flush_context_cmd(chip, space->context_tbl[i],
+				       TPM_TRANSMIT_UNLOCKED);
 		space->context_tbl[i] = ~0;
 	}
 
+	for (i = 0, offset = 0; i < ARRAY_SIZE(space->session_tbl); i++) {
+		if (!space->session_tbl[i])
+			continue;
+
+		rc = tpm2_save_context(chip, space->session_tbl[i],
+				       space->session_buf, PAGE_SIZE,
+				       &offset);
+
+		if (rc == -ENOENT) {
+			/* handle error saving session, just forget it */
+			space->session_tbl[i] = 0;
+		} else if (rc < 0) {
+			tpm2_flush_space(chip);
+			return rc;
+		}
+	}
+
 	return 0;
 }
 
@@ -335,7 +441,10 @@ int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
 
 	memcpy(&space->context_tbl, &chip->work_space.context_tbl,
 	       sizeof(space->context_tbl));
+	memcpy(&space->session_tbl, &chip->work_space.session_tbl,
+	       sizeof(space->session_tbl));
 	memcpy(space->context_buf, chip->work_space.context_buf, PAGE_SIZE);
+	memcpy(space->session_buf, chip->work_space.session_buf, PAGE_SIZE);
 
 	return 0;
 }
diff --git a/drivers/char/tpm/tpms-dev.c b/drivers/char/tpm/tpms-dev.c
index 5720885..4c98db8 100644
--- a/drivers/char/tpm/tpms-dev.c
+++ b/drivers/char/tpm/tpms-dev.c
@@ -39,7 +39,7 @@ static int tpms_release(struct inode *inode, struct file *file)
 	struct tpms_priv *priv = container_of(fpriv, struct tpms_priv, priv);
 
 	tpm_common_release(file, fpriv);
-	tpm2_del_space(&priv->space);
+	tpm2_del_space(fpriv->chip, &priv->space);
 	kfree(priv);
 
 	return 0;
-- 
2.9.3

Re: [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

[Jarkko Sakkinen]

On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> +		rc = tpm2_load_context(chip, space->session_buf,
> +				       &offset, &handle);
> +		if (rc == -ENOENT) {
> +			/* load failed, just forget session */
> +			space->session_tbl[i] = 0;

This is my only concern in this commit. Should we also in this case just
flush the space or not?

/Jarkko

Re: [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

[James Bottomley]

On Fri, 2017-02-10 at 10:52 +0200, Jarkko Sakkinen wrote:
> On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> > +		rc = tpm2_load_context(chip, space->session_buf,
> > +				       &offset, &handle);
> > +		if (rc == -ENOENT) {
> > +			/* load failed, just forget session */
> > +			space->session_tbl[i] = 0;
> 
> This is my only concern in this commit. Should we also in this case 
> just flush the space or not?

I elected not to.  If the handle is flushed by an external resource
manager, we get this event.  If the RM and the app agreed to release
the session handle, then flushing the space would be overkill because
it would destroy the client session, so simply removing the handle
works.  If the client tries to use the session again, it gets an error
and if it doesn't everything just works, which seems to be optimal.

James

Re: [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code'

[Jarkko Sakkinen]

On Fri, Feb 10, 2017 at 08:11:18AM -0800, James Bottomley wrote:
> On Fri, 2017-02-10 at 10:52 +0200, Jarkko Sakkinen wrote:
> > On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> > > +		rc = tpm2_load_context(chip, space->session_buf,
> > > +				       &offset, &handle);
> > > +		if (rc == -ENOENT) {
> > > +			/* load failed, just forget session */
> > > +			space->session_tbl[i] = 0;
> > 
> > This is my only concern in this commit. Should we also in this case 
> > just flush the space or not?
> 
> I elected not to.  If the handle is flushed by an external resource
> manager, we get this event.  If the RM and the app agreed to release
> the session handle, then flushing the space would be overkill because
> it would destroy the client session, so simply removing the handle
> works.  If the client tries to use the session again, it gets an error
> and if it doesn't everything just works, which seems to be optimal.
> 
> James

Makes sense. Just wanted the check the logic you had in this decision.

/Jarkko

Re: [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

[Jarkko Sakkinen]

On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> From: James Bottomley <James.Bottomley@HansenPartnership.com>
> 
> Sessions are different from transient objects in that their handles
> may not be virtualized (because they're used for some hmac
> calculations).  Additionally when a session is context saved, a
> vestigial memory remains in the TPM and if it is also flushed, that
> will be lost and the session context will refuse to load next time, so
> the code is updated to flush only transient objects after a context
> save.  Add a separate array (chip->session_tbl) to save and restore
> sessions by handle.  Use the failure of a context save or load to
> signal that the session has been flushed from the TPM and we can
> remove its memory from chip->session_tbl.
> 
> Sessions are also isolated during each instance of a tpm space.  This
> means that spaces shouldn't be able to see each other's sessions and
> is enforced by ensuring that a space user may only refer to sessions
> handles that are present in their own chip->session_tbl.  Finally when
> a space is closed, all the sessions belonging to it should be flushed
> so the handles may be re-used by other spaces.
> 
> Note that if we get a session save or load error, all sessions are
> effectively flushed.  Even though we restore the session buffer, all
> the old sessions will refuse to load after the flush and they'll be
> purged from our session memory.  This means that while transient
> context handling is still soft in the face of errors, session handling
> is hard (any failure of the model means all sessions are lost).
> 
> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
> ---
>  drivers/char/tpm/tpm-chip.c   |   6 +++
>  drivers/char/tpm/tpm.h        |   4 +-
>  drivers/char/tpm/tpm2-space.c | 115 ++++++++++++++++++++++++++++++++++++++++--
>  drivers/char/tpm/tpms-dev.c   |   2 +-
>  4 files changed, 122 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index c71c353..e8536ab 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -130,6 +130,7 @@ static void tpm_dev_release(struct device *dev)
>  
>  	kfree(chip->log.bios_event_log);
>  	kfree(chip->work_space.context_buf);
> +	kfree(chip->work_space.session_buf);
>  	kfree(chip);
>  }
>  
> @@ -224,6 +225,11 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
>  		rc = -ENOMEM;
>  		goto out;
>  	}
> +	chip->work_space.session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
> +	if (!chip->work_space.session_buf) {
> +		rc = -ENOMEM;
> +		goto out;
> +	}
>  
>  	return chip;
>  
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index 8670cc5..9261223 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -160,6 +160,8 @@ enum tpm2_cc_attrs {
>  struct tpm_space {
>  	u32 context_tbl[3];
>  	u8 *context_buf;
> +	u32 session_tbl[3];
> +	u8 *session_buf;
>  };
>  
>  enum tpm_chip_flags {
> @@ -588,7 +590,7 @@ int tpm2_probe(struct tpm_chip *chip);
>  ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip);
>  int tpm2_find_cc(struct tpm_chip *chip, u32 cc);
>  int tpm2_init_space(struct tpm_space *space);
> -void tpm2_del_space(struct tpm_space *space);
> +void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space);
>  int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
>  		       u8 *cmd);
>  int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
> diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
> index d241c2a..fb817ca 100644
> --- a/drivers/char/tpm/tpm2-space.c
> +++ b/drivers/char/tpm/tpm2-space.c
> @@ -32,18 +32,39 @@ struct tpm2_context {
>  	__be16 blob_size;
>  } __packed;
>  
> +static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++) {
> +		if (space->session_tbl[i])
> +			tpm2_flush_context_cmd(chip, space->session_tbl[i],
> +					       TPM_TRANSMIT_UNLOCKED);
> +	}
> +}
> +
>  int tpm2_init_space(struct tpm_space *space)
>  {
>  	space->context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
>  	if (!space->context_buf)
>  		return -ENOMEM;
>  
> +	space->session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
> +	if (space->session_buf == NULL) {
> +		kfree(space->context_buf);
> +		return -ENOMEM;
> +	}
> +
>  	return 0;
>  }
>  
> -void tpm2_del_space(struct tpm_space *space)
> +void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space)
>  {
> +	mutex_lock(&chip->tpm_mutex);
> +	tpm2_flush_sessions(chip, space);
> +	mutex_unlock(&chip->tpm_mutex);
>  	kfree(space->context_buf);
> +	kfree(space->session_buf);
>  }
>  
>  static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
> @@ -69,6 +90,20 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
>  			 __func__, rc);
>  		tpm_buf_destroy(&tbuf);
>  		return -EFAULT;
> +	} else if (tpm2_rc_value(rc) == TPM2_RC_HANDLE ||
> +		   rc == TPM2_RC_REFERENCE_H0) {
> +		/*
> +		 * TPM_RC_HANDLE means that the session context can't
> +		 * be loaded because of an internal counter mismatch
> +		 * that makes the TPM think there might have been a
> +		 * replay.  This might happen if the context was saved
> +		 * and loaded outside the space.
> +		 *
> +		 * TPM_RC_REFERENCE_H0 means the session has been
> +		 * flushed outside the space
> +		 */
> +		rc = -ENOENT;
> +		tpm_buf_destroy(&tbuf);
>  	} else if (rc > 0) {
>  		dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
>  			 __func__, rc);
> @@ -121,12 +156,30 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
>  	}
>  
>  	memcpy(&buf[*offset], &tbuf.data[TPM_HEADER_SIZE], body_size);
> -	tpm2_flush_context_cmd(chip, handle, TPM_TRANSMIT_UNLOCKED);
>  	*offset += body_size;
>  	tpm_buf_destroy(&tbuf);
>  	return 0;
>  }
>  
> +static int tpm2_session_add(struct tpm_chip *chip, u32 handle)
> +{
> +	struct tpm_space *space = &chip->work_space;
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++)
> +		if (space->session_tbl[i] == 0)
> +			break;
> +	if (i == ARRAY_SIZE(space->session_tbl)) {
> +		dev_err(&chip->dev, "out of session slots\n");

This really should be dev_dbg.

/Jarkko

Re: [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

[James Bottomley]

On Fri, 2017-02-10 at 14:32 +0200, Jarkko Sakkinen wrote:
> On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> > From: James Bottomley <James.Bottomley@HansenPartnership.com>
[...] 
> > +static int tpm2_session_add(struct tpm_chip *chip, u32 handle)
> > +{
> > +	struct tpm_space *space = &chip->work_space;
> > +	int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++)
> > +		if (space->session_tbl[i] == 0)
> > +			break;
> > +	if (i == ARRAY_SIZE(space->session_tbl)) {
> > +		dev_err(&chip->dev, "out of session slots\n");
> 
> This really should be dev_dbg.

This was my reply to the comment the last time:

    I can do that, but I think this should be higher than debug.  If
    this trips, something an application was doing will fail with a non
    TPM error and someone may wish to investigate why.  Having a kernel
    message would help with that (but they won't see it if it's debug).

    I'm also leaning towards the idea that we should actually have one
    more _tbl slot than we know the TPM does, so that if someone goes
    over it's the TPM that gives them a real TPM out of memory error
    rather than the space code returning -ENOMEM.

    If you agree, I think it should be four for both sessions_tbl and
    context_tbl.

So I really don't think it should be debug.  Could we compromise on
dev_info?

James

Re: [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

[Jarkko Sakkinen]

On Fri, Feb 10, 2017 at 08:17:11AM -0800, James Bottomley wrote:
> On Fri, 2017-02-10 at 14:32 +0200, Jarkko Sakkinen wrote:
> > On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> > > From: James Bottomley <James.Bottomley@HansenPartnership.com>
> [...] 
> > > +static int tpm2_session_add(struct tpm_chip *chip, u32 handle)
> > > +{
> > > +	struct tpm_space *space = &chip->work_space;
> > > +	int i;
> > > +
> > > +	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++)
> > > +		if (space->session_tbl[i] == 0)
> > > +			break;
> > > +	if (i == ARRAY_SIZE(space->session_tbl)) {
> > > +		dev_err(&chip->dev, "out of session slots\n");
> > 
> > This really should be dev_dbg.
> 
> This was my reply to the comment the last time:
> 
>     I can do that, but I think this should be higher than debug.  If
>     this trips, something an application was doing will fail with a non
>     TPM error and someone may wish to investigate why.  Having a kernel
>     message would help with that (but they won't see it if it's debug).
> 
>     I'm also leaning towards the idea that we should actually have one
>     more _tbl slot than we know the TPM does, so that if someone goes
>     over it's the TPM that gives them a real TPM out of memory error
>     rather than the space code returning -ENOMEM.
> 
>     If you agree, I think it should be four for both sessions_tbl and
>     context_tbl.
> 
> So I really don't think it should be debug.  Could we compromise on
> dev_info?
> 
> James

Oops, I'm sorry about that. I use the release chaos as an excuse :-)
I would lower it to dev_warn().

/Jarkko

Re: [tpmdd-devel] [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

[James Bottomley]

On Fri, 2017-02-10 at 21:10 +0200, Jarkko Sakkinen wrote:
> On Fri, Feb 10, 2017 at 08:17:11AM -0800, James Bottomley wrote:
> > On Fri, 2017-02-10 at 14:32 +0200, Jarkko Sakkinen wrote:
> > > On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> > > > From: James Bottomley <James.Bottomley@HansenPartnership.com>
> > [...] 
> > > > +static int tpm2_session_add(struct tpm_chip *chip, u32 handle)
> > > > +{
> > > > +	struct tpm_space *space = &chip->work_space;
> > > > +	int i;
> > > > +
> > > > +	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++)
> > > > +		if (space->session_tbl[i] == 0)
> > > > +			break;
> > > > +	if (i == ARRAY_SIZE(space->session_tbl)) {
> > > > +		dev_err(&chip->dev, "out of session slots\n");
> > > 
> > > This really should be dev_dbg.
> > 
> > This was my reply to the comment the last time:
> > 
> >     I can do that, but I think this should be higher than debug. 
> >  If
> >     this trips, something an application was doing will fail with a
> > non
> >     TPM error and someone may wish to investigate why.  Having a
> > kernel
> >     message would help with that (but they won't see it if it's
> > debug).
> > 
> >     I'm also leaning towards the idea that we should actually have
> > one
> >     more _tbl slot than we know the TPM does, so that if someone
> > goes
> >     over it's the TPM that gives them a real TPM out of memory
> > error
> >     rather than the space code returning -ENOMEM.
> > 
> >     If you agree, I think it should be four for both sessions_tbl
> > and
> >     context_tbl.
> > 
> > So I really don't think it should be debug.  Could we compromise on
> > dev_info?
> > 
> > James
> 
> Oops, I'm sorry about that. I use the release chaos as an excuse :-)
> I would lower it to dev_warn().

That works.  Do you want me to resend the patch?

James

Re: [tpmdd-devel] [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

[Jarkko Sakkinen]

On Fri, Feb 10, 2017 at 11:12:15AM -0800, James Bottomley wrote:
> On Fri, 2017-02-10 at 21:10 +0200, Jarkko Sakkinen wrote:
> > On Fri, Feb 10, 2017 at 08:17:11AM -0800, James Bottomley wrote:
> > > On Fri, 2017-02-10 at 14:32 +0200, Jarkko Sakkinen wrote:
> > > > On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> > > > > From: James Bottomley <James.Bottomley@HansenPartnership.com>
> > > [...] 
> > > > > +static int tpm2_session_add(struct tpm_chip *chip, u32 handle)
> > > > > +{
> > > > > +	struct tpm_space *space = &chip->work_space;
> > > > > +	int i;
> > > > > +
> > > > > +	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++)
> > > > > +		if (space->session_tbl[i] == 0)
> > > > > +			break;
> > > > > +	if (i == ARRAY_SIZE(space->session_tbl)) {
> > > > > +		dev_err(&chip->dev, "out of session slots\n");
> > > > 
> > > > This really should be dev_dbg.
> > > 
> > > This was my reply to the comment the last time:
> > > 
> > >     I can do that, but I think this should be higher than debug. 
> > >  If
> > >     this trips, something an application was doing will fail with a
> > > non
> > >     TPM error and someone may wish to investigate why.  Having a
> > > kernel
> > >     message would help with that (but they won't see it if it's
> > > debug).
> > > 
> > >     I'm also leaning towards the idea that we should actually have
> > > one
> > >     more _tbl slot than we know the TPM does, so that if someone
> > > goes
> > >     over it's the TPM that gives them a real TPM out of memory
> > > error
> > >     rather than the space code returning -ENOMEM.
> > > 
> > >     If you agree, I think it should be four for both sessions_tbl
> > > and
> > >     context_tbl.
> > > 
> > > So I really don't think it should be debug.  Could we compromise on
> > > dev_info?
> > > 
> > > James
> > 
> > Oops, I'm sorry about that. I use the release chaos as an excuse :-)
> > I would lower it to dev_warn().
> 
> That works.  Do you want me to resend the patch?
> 
> James

No need for that.

/Jarkko

Re: [PATCH 0/6] in-kernel resource manager

[Jarkko Sakkinen]

On Wed, Feb 08, 2017 at 01:07:02PM +0200, Jarkko Sakkinen wrote:
> This patch set adds support for TPM spaces that provide an isolated
> for transient objects and HMAC and policy sessions. A space is swapped
> into TPM volatile memory only when it is used and swapped out after
> the use.
> 
> There's a test script for trying out TPM spaces in
> 
>   git://git.infradead.org/users/jjs/tpm2-scripts.git
> 
> A simple smoke test can be run by
> 
>   sudo python -m unittest -v tpm2_smoke.SpaceTest   

There is also tabrm-v1 branch in my GIT tree.

/Jarkko