Merge tag 'tpmdd-next-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd

Pull TPM updates from Jarkko Sakkinen:
 "These are the changes for the TPM driver with a single major new
  feature: TPM bus encryption and integrity protection. The key pair on
  TPM side is generated from so called null random seed per power on of
  the machine [1]. This supports the TPM encryption of the hard drive by
  adding layer of protection against bus interposer attacks.

  Other than that, a few minor fixes and documentation for tpm_tis to
  clarify basics of TPM localities for future patch review discussions
  (will be extended and refined over times, just a seed)"

Link: https://lore.kernel.org/linux-integrity/20240429202811.13643-1-James.Bottomley@HansenPartnership.com/ [1]

* tag 'tpmdd-next-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd: (28 commits)
  Documentation: tpm: Add TPM security docs toctree entry
  tpm: disable the TPM if NULL name changes
  Documentation: add tpm-security.rst
  tpm: add the null key name as a sysfs export
  KEYS: trusted: Add session encryption protection to the seal/unseal path
  tpm: add session encryption protection to tpm2_get_random()
  tpm: add hmac checks to tpm2_pcr_extend()
  tpm: Add the rest of the session HMAC API
  tpm: Add HMAC session name/handle append
  tpm: Add HMAC session start and end functions
  tpm: Add TCG mandated Key Derivation Functions (KDFs)
  tpm: Add NULL primary creation
  tpm: export the context save and load commands
  tpm: add buffer function to point to returned parameters
  crypto: lib - implement library version of AES in CFB mode
  KEYS: trusted: tpm2: Use struct tpm_buf for sized buffers
  tpm: Add tpm_buf_read_{u8,u16,u32}
  tpm: TPM2B formatted buffers
  tpm: Store the length of the tpm_buf data separately.
  tpm: Update struct tpm_buf documentation comments
  ...

Documentation/devicetree/bindings/tpm/tcg,tpm-tis-i2c.yaml

@@ -32,6 +32,7 @@ properties:
           - enum:
               - infineon,slb9673
               - nuvoton,npct75x
+              - st,st33ktpm2xi2c
           - const: tcg,tpm-tis-i2c
 
       - description: TPM 1.2 and 2.0 chips with vendor-specific I²C interface

Documentation/security/tpm/index.rst

@@ -5,6 +5,8 @@ Trusted Platform Module documentation
 .. toctree::
 
    tpm_event_log
+   tpm-security
+   tpm_tis
    tpm_vtpm_proxy
    xen-tpmfront
    tpm_ftpm_tee

Documentation/security/tpm/tpm_tis.rst

+.. SPDX-License-Identifier: GPL-2.0
+
+=========================
+TPM FIFO interface driver
+=========================
+
+TCG PTP Specification defines two interface types: FIFO and CRB. The former is
+based on sequenced read and write operations,  and the latter is based on a
+buffer containing the full command or response.
+
+FIFO (First-In-First-Out) interface is used by the tpm_tis_core dependent
+drivers. Originally Linux had only a driver called tpm_tis, which covered
+memory mapped (aka MMIO) interface but it was later on extended to cover other
+physical interfaces supported by the TCG standard.
+
+For historical reasons above the original MMIO driver is called tpm_tis and the
+framework for FIFO drivers is named as tpm_tis_core. The postfix "tis" in
+tpm_tis comes from the TPM Interface Specification, which is the hardware
+interface specification for TPM 1.x chips.
+
+Communication is based on a 20 KiB buffer shared by the TPM chip through a
+hardware bus or memory map, depending on the physical wiring. The buffer is
+further split into five equal-size 4 KiB buffers, which provide equivalent
+sets of registers for communication between the CPU and TPM. These
+communication endpoints are called localities in the TCG terminology.
+
+When the kernel wants to send commands to the TPM chip, it first reserves
+locality 0 by setting the requestUse bit in the TPM_ACCESS register. The bit is
+cleared by the chip when the access is granted. Once it completes its
+communication, the kernel writes the TPM_ACCESS.activeLocality bit. This
+informs the chip that the locality has been relinquished.
+
+Pending localities are served in order by the chip in descending order, one at
+a time:
+
+- Locality 0 has the lowest priority.
+- Locality 5 has the highest priority.
+
+Further information on the purpose and meaning of the localities can be found
+in section 3.2 of the TCG PC Client Platform TPM Profile Specification.
+
+References
+==========
+
+TCG PC Client Platform TPM Profile (PTP) Specification
+https://trustedcomputinggroup.org/resource/pc-client-platform-tpm-profile-ptp-specification/

drivers/char/tpm/Kconfig

@@ -27,6 +27,20 @@ menuconfig TCG_TPM
 
 if TCG_TPM
 
+config TCG_TPM2_HMAC
+	bool "Use HMAC and encrypted transactions on the TPM bus"
+	default y
+	select CRYPTO_ECDH
+	select CRYPTO_LIB_AESCFB
+	select CRYPTO_LIB_SHA256
+	help
+	  Setting this causes us to deploy a scheme which uses request
+	  and response HMACs in addition to encryption for
+	  communicating with the TPM to prevent or detect bus snooping
+	  and interposer attacks (see tpm-security.rst).  Saying Y
+	  here adds some encryption overhead to all kernel to TPM
+	  transactions.
+
 config HW_RANDOM_TPM
 	bool "TPM HW Random Number Generator support"
 	depends on TCG_TPM && HW_RANDOM && !(TCG_TPM=y && HW_RANDOM=m)
@@ -149,6 +163,7 @@ config TCG_NSC
 config TCG_ATMEL
 	tristate "Atmel TPM Interface"
 	depends on PPC64 || HAS_IOPORT_MAP
+	depends on HAS_IOPORT
 	help
 	  If you have a TPM security chip from Atmel say Yes and it 
 	  will be accessible from within Linux.  To compile this driver 
@@ -156,7 +171,7 @@ config TCG_ATMEL
 
 config TCG_INFINEON
 	tristate "Infineon Technologies TPM Interface"
-	depends on PNP
+	depends on PNP || COMPILE_TEST
 	help
 	  If you have a TPM security chip from Infineon Technologies
 	  (either SLD 9630 TT 1.1 or SLB 9635 TT 1.2) say Yes and it

drivers/char/tpm/Makefile

@@ -15,7 +15,9 @@ tpm-y += tpm-sysfs.o
 tpm-y += eventlog/common.o
 tpm-y += eventlog/tpm1.o
 tpm-y += eventlog/tpm2.o
+tpm-y += tpm-buf.o
 
+tpm-$(CONFIG_TCG_TPM2_HMAC) += tpm2-sessions.o
 tpm-$(CONFIG_ACPI) += tpm_ppi.o eventlog/acpi.o
 tpm-$(CONFIG_EFI) += eventlog/efi.o
 tpm-$(CONFIG_OF) += eventlog/of.o

drivers/char/tpm/eventlog/acpi.c

@@ -142,7 +142,6 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
 
 	log->bios_event_log_end = log->bios_event_log + len;
 
-	ret = -EIO;
 	virt = acpi_os_map_iomem(start, len);
 	if (!virt) {
 		dev_warn(&chip->dev, "%s: Failed to map ACPI memory\n", __func__);

drivers/char/tpm/tpm-buf.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Handling of TPM command and other buffers.
+ */
+
+#include <linux/tpm_command.h>
+#include <linux/module.h>
+#include <linux/tpm.h>
+
+/**
+ * tpm_buf_init() - Allocate and initialize a TPM command
+ * @buf:	A &tpm_buf
+ * @tag:	TPM_TAG_RQU_COMMAND, TPM2_ST_NO_SESSIONS or TPM2_ST_SESSIONS
+ * @ordinal:	A command ordinal
+ *
+ * Return: 0 or -ENOMEM
+ */
+int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal)
+{
+	buf->data = (u8 *)__get_free_page(GFP_KERNEL);
+	if (!buf->data)
+		return -ENOMEM;
+
+	tpm_buf_reset(buf, tag, ordinal);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_buf_init);
+
+/**
+ * tpm_buf_reset() - Initialize a TPM command
+ * @buf:	A &tpm_buf
+ * @tag:	TPM_TAG_RQU_COMMAND, TPM2_ST_NO_SESSIONS or TPM2_ST_SESSIONS
+ * @ordinal:	A command ordinal
+ */
+void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal)
+{
+	struct tpm_header *head = (struct tpm_header *)buf->data;
+
+	WARN_ON(tag != TPM_TAG_RQU_COMMAND && tag != TPM2_ST_NO_SESSIONS &&
+		tag != TPM2_ST_SESSIONS && tag != 0);
+
+	buf->flags = 0;
+	buf->length = sizeof(*head);
+	head->tag = cpu_to_be16(tag);
+	head->length = cpu_to_be32(sizeof(*head));
+	head->ordinal = cpu_to_be32(ordinal);
+	buf->handles = 0;
+}
+EXPORT_SYMBOL_GPL(tpm_buf_reset);
+
+/**
+ * tpm_buf_init_sized() - Allocate and initialize a sized (TPM2B) buffer
+ * @buf:	A @tpm_buf
+ *
+ * Return: 0 or -ENOMEM
+ */
+int tpm_buf_init_sized(struct tpm_buf *buf)
+{
+	buf->data = (u8 *)__get_free_page(GFP_KERNEL);
+	if (!buf->data)
+		return -ENOMEM;
+
+	tpm_buf_reset_sized(buf);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_buf_init_sized);
+
+/**
+ * tpm_buf_reset_sized() - Initialize a sized buffer
+ * @buf:	A &tpm_buf
+ */
+void tpm_buf_reset_sized(struct tpm_buf *buf)
+{
+	buf->flags = TPM_BUF_TPM2B;
+	buf->length = 2;
+	buf->data[0] = 0;
+	buf->data[1] = 0;
+}
+EXPORT_SYMBOL_GPL(tpm_buf_reset_sized);
+
+void tpm_buf_destroy(struct tpm_buf *buf)
+{
+	free_page((unsigned long)buf->data);
+}
+EXPORT_SYMBOL_GPL(tpm_buf_destroy);
+
+/**
+ * tpm_buf_length() - Return the number of bytes consumed by the data
+ * @buf:	A &tpm_buf
+ *
+ * Return: The number of bytes consumed by the buffer
+ */
+u32 tpm_buf_length(struct tpm_buf *buf)
+{
+	return buf->length;
+}
+EXPORT_SYMBOL_GPL(tpm_buf_length);
+
+/**
+ * tpm_buf_append() - Append data to an initialized buffer
+ * @buf:	A &tpm_buf
+ * @new_data:	A data blob
+ * @new_length:	Size of the appended data
+ */
+void tpm_buf_append(struct tpm_buf *buf, const u8 *new_data, u16 new_length)
+{
+	/* Return silently if overflow has already happened. */
+	if (buf->flags & TPM_BUF_OVERFLOW)
+		return;
+
+	if ((buf->length + new_length) > PAGE_SIZE) {
+		WARN(1, "tpm_buf: write overflow\n");
+		buf->flags |= TPM_BUF_OVERFLOW;
+		return;
+	}
+
+	memcpy(&buf->data[buf->length], new_data, new_length);
+	buf->length += new_length;
+
+	if (buf->flags & TPM_BUF_TPM2B)
+		((__be16 *)buf->data)[0] = cpu_to_be16(buf->length - 2);
+	else
+		((struct tpm_header *)buf->data)->length = cpu_to_be32(buf->length);
+}
+EXPORT_SYMBOL_GPL(tpm_buf_append);
+
+void tpm_buf_append_u8(struct tpm_buf *buf, const u8 value)
+{
+	tpm_buf_append(buf, &value, 1);
+}
+EXPORT_SYMBOL_GPL(tpm_buf_append_u8);
+
+void tpm_buf_append_u16(struct tpm_buf *buf, const u16 value)
+{
+	__be16 value2 = cpu_to_be16(value);
+
+	tpm_buf_append(buf, (u8 *)&value2, 2);
+}
+EXPORT_SYMBOL_GPL(tpm_buf_append_u16);
+
+void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
+{
+	__be32 value2 = cpu_to_be32(value);
+
+	tpm_buf_append(buf, (u8 *)&value2, 4);
+}
+EXPORT_SYMBOL_GPL(tpm_buf_append_u32);
+
+/**
+ * tpm_buf_read() - Read from a TPM buffer
+ * @buf:	&tpm_buf instance
+ * @offset:	offset within the buffer
+ * @count:	the number of bytes to read
+ * @output:	the output buffer
+ */
+static void tpm_buf_read(struct tpm_buf *buf, off_t *offset, size_t count, void *output)
+{
+	off_t next_offset;
+
+	/* Return silently if overflow has already happened. */
+	if (buf->flags & TPM_BUF_BOUNDARY_ERROR)
+		return;
+
+	next_offset = *offset + count;
+	if (next_offset > buf->length) {
+		WARN(1, "tpm_buf: read out of boundary\n");
+		buf->flags |= TPM_BUF_BOUNDARY_ERROR;
+		return;
+	}
+
+	memcpy(output, &buf->data[*offset], count);
+	*offset = next_offset;
+}
+
+/**
+ * tpm_buf_read_u8() - Read 8-bit word from a TPM buffer
+ * @buf:	&tpm_buf instance
+ * @offset:	offset within the buffer
+ *
+ * Return: next 8-bit word
+ */
+u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset)
+{
+	u8 value;
+
+	tpm_buf_read(buf, offset, sizeof(value), &value);
+
+	return value;
+}
+EXPORT_SYMBOL_GPL(tpm_buf_read_u8);
+
+/**
+ * tpm_buf_read_u16() - Read 16-bit word from a TPM buffer
+ * @buf:	&tpm_buf instance
+ * @offset:	offset within the buffer
+ *
+ * Return: next 16-bit word
+ */
+u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset)
+{
+	u16 value;
+
+	tpm_buf_read(buf, offset, sizeof(value), &value);
+
+	return be16_to_cpu(value);
+}
+EXPORT_SYMBOL_GPL(tpm_buf_read_u16);
+
+/**
+ * tpm_buf_read_u32() - Read 32-bit word from a TPM buffer
+ * @buf:	&tpm_buf instance
+ * @offset:	offset within the buffer
+ *
+ * Return: next 32-bit word
+ */
+u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset)
+{
+	u32 value;
+
+	tpm_buf_read(buf, offset, sizeof(value), &value);
+
+	return be32_to_cpu(value);
+}
+EXPORT_SYMBOL_GPL(tpm_buf_read_u32);
+
+static u16 tpm_buf_tag(struct tpm_buf *buf)
+{
+	struct tpm_header *head = (struct tpm_header *)buf->data;
+
+	return be16_to_cpu(head->tag);
+}
+
+/**
+ * tpm_buf_parameters - return the TPM response parameters area of the tpm_buf
+ * @buf: tpm_buf to use
+ *
+ * Where the parameters are located depends on the tag of a TPM
+ * command (it's immediately after the header for TPM_ST_NO_SESSIONS
+ * or 4 bytes after for TPM_ST_SESSIONS). Evaluate this and return a
+ * pointer to the first byte of the parameters area.
+ *
+ * @return: pointer to parameters area
+ */
+u8 *tpm_buf_parameters(struct tpm_buf *buf)
+{
+	int offset = TPM_HEADER_SIZE;
+
+	if (tpm_buf_tag(buf) == TPM2_ST_SESSIONS)
+		offset += 4;
+
+	return &buf->data[offset];
+}

drivers/char/tpm/tpm-chip.c

@@ -158,6 +158,9 @@ int tpm_try_get_ops(struct tpm_chip *chip)
 {
 	int rc = -EIO;
 
+	if (chip->flags & TPM_CHIP_FLAG_DISABLE)
+		return rc;
+
 	get_device(&chip->dev);
 
 	down_read(&chip->ops_sem);
@@ -275,6 +278,9 @@ static void tpm_dev_release(struct device *dev)
 	kfree(chip->work_space.context_buf);
 	kfree(chip->work_space.session_buf);
 	kfree(chip->allocated_banks);
+#ifdef CONFIG_TCG_TPM2_HMAC
+	kfree(chip->auth);
+#endif
 	kfree(chip);
 }
 

drivers/char/tpm/tpm-interface.c

@@ -232,6 +232,7 @@ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf,
 	if (len < min_rsp_body_length + TPM_HEADER_SIZE)
 		return -EFAULT;
 
+	buf->length = len;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(tpm_transmit_cmd);
@@ -342,31 +343,6 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
 }
 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 
-/**
- * tpm_send - send a TPM command
- * @chip:	a &struct tpm_chip instance, %NULL for the default chip
- * @cmd:	a TPM command buffer
- * @buflen:	the length of the TPM command buffer
- *
- * Return: same as with tpm_transmit_cmd()
- */
-int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen)
-{
-	struct tpm_buf buf;
-	int rc;
-
-	chip = tpm_find_get_ops(chip);
-	if (!chip)
-		return -ENODEV;
-
-	buf.data = cmd;
-	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to a send a command");
-
-	tpm_put_ops(chip);
-	return rc;
-}
-EXPORT_SYMBOL_GPL(tpm_send);
-
 int tpm_auto_startup(struct tpm_chip *chip)
 {
 	int rc;

drivers/char/tpm/tpm-sysfs.c

@@ -309,6 +309,21 @@ static ssize_t tpm_version_major_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(tpm_version_major);
 
+#ifdef CONFIG_TCG_TPM2_HMAC
+static ssize_t null_name_show(struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	struct tpm_chip *chip = to_tpm_chip(dev);
+	int size = TPM2_NAME_SIZE;
+
+	bin2hex(buf, chip->null_key_name, size);
+	size *= 2;
+	buf[size++] = '\n';
+	return size;
+}
+static DEVICE_ATTR_RO(null_name);
+#endif
+
 static struct attribute *tpm1_dev_attrs[] = {
 	&dev_attr_pubek.attr,
 	&dev_attr_pcrs.attr,
@@ -326,6 +341,9 @@ static struct attribute *tpm1_dev_attrs[] = {
 
 static struct attribute *tpm2_dev_attrs[] = {
 	&dev_attr_tpm_version_major.attr,
+#ifdef CONFIG_TCG_TPM2_HMAC
+	&dev_attr_null_name.attr,
+#endif
 	NULL
 };
 

drivers/char/tpm/tpm.h

@@ -312,9 +312,23 @@ int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, void *buf,
 		      size_t *bufsiz);
 int tpm_devs_add(struct tpm_chip *chip);
 void tpm_devs_remove(struct tpm_chip *chip);
+int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
+		      unsigned int buf_size, unsigned int *offset);
+int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
+		      unsigned int *offset, u32 *handle);
 
 void tpm_bios_log_setup(struct tpm_chip *chip);
 void tpm_bios_log_teardown(struct tpm_chip *chip);
 int tpm_dev_common_init(void);
 void tpm_dev_common_exit(void);
+
+#ifdef CONFIG_TCG_TPM2_HMAC
+int tpm2_sessions_init(struct tpm_chip *chip);
+#else
+static inline int tpm2_sessions_init(struct tpm_chip *chip)
+{
+	return 0;
+}
+#endif
+
 #endif

drivers/char/tpm/tpm2-cmd.c

@@ -216,13 +216,6 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
 	return rc;
 }
 
-struct tpm2_null_auth_area {
-	__be32  handle;
-	__be16  nonce_size;
-	u8  attributes;
-	__be16  auth_size;
-} __packed;
-
 /**
  * tpm2_pcr_extend() - extend a PCR value
  *
@@ -236,24 +229,22 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
 		    struct tpm_digest *digests)
 {
 	struct tpm_buf buf;
-	struct tpm2_null_auth_area auth_area;
 	int rc;
 	int i;
 
-	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
+	rc = tpm2_start_auth_session(chip);
 	if (rc)
 		return rc;
 
-	tpm_buf_append_u32(&buf, pcr_idx);
+	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
+	if (rc) {
+		tpm2_end_auth_session(chip);
+		return rc;
+	}
 
-	auth_area.handle = cpu_to_be32(TPM2_RS_PW);
-	auth_area.nonce_size = 0;
-	auth_area.attributes = 0;
-	auth_area.auth_size = 0;
+	tpm_buf_append_name(chip, &buf, pcr_idx, NULL);
+	tpm_buf_append_hmac_session(chip, &buf, 0, NULL, 0);
 
-	tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area));
-	tpm_buf_append(&buf, (const unsigned char *)&auth_area,
-		       sizeof(auth_area));
 	tpm_buf_append_u32(&buf, chip->nr_allocated_banks);
 
 	for (i = 0; i < chip->nr_allocated_banks; i++) {
@@ -262,7 +253,9 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
 			       chip->allocated_banks[i].digest_size);
 	}
 
+	tpm_buf_fill_hmac_session(chip, &buf);
 	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting extend a PCR value");
+	rc = tpm_buf_check_hmac_response(chip, &buf, rc);
 
 	tpm_buf_destroy(&buf);
 
@@ -299,25 +292,35 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
 	if (!num_bytes || max > TPM_MAX_RNG_DATA)
 		return -EINVAL;
 
-	err = tpm_buf_init(&buf, 0, 0);
+	err = tpm2_start_auth_session(chip);
 	if (err)
 		return err;
 
+	err = tpm_buf_init(&buf, 0, 0);
+	if (err) {
+		tpm2_end_auth_session(chip);
+		return err;
+	}
+
 	do {
-		tpm_buf_reset(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_RANDOM);
+		tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
+		tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT
+						| TPM2_SA_CONTINUE_SESSION,
+						NULL, 0);
 		tpm_buf_append_u16(&buf, num_bytes);
+		tpm_buf_fill_hmac_session(chip, &buf);
 		err = tpm_transmit_cmd(chip, &buf,
 				       offsetof(struct tpm2_get_random_out,
 						buffer),
 				       "attempting get random");
+		err = tpm_buf_check_hmac_response(chip, &buf, err);
 		if (err) {
 			if (err > 0)
 				err = -EIO;
 			goto out;
 		}
 
-		out = (struct tpm2_get_random_out *)
-			&buf.data[TPM_HEADER_SIZE];
+		out = (struct tpm2_get_random_out *)tpm_buf_parameters(&buf);
 		recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
 		if (tpm_buf_length(&buf) <
 		    TPM_HEADER_SIZE +
@@ -334,9 +337,12 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
 	} while (retries-- && total < max);
 
 	tpm_buf_destroy(&buf);
+	tpm2_end_auth_session(chip);
+
 	return total ? total : -EIO;
 out:
 	tpm_buf_destroy(&buf);
+	tpm2_end_auth_session(chip);
 	return err;
 }
 
@@ -759,6 +765,11 @@ int tpm2_auto_startup(struct tpm_chip *chip)
 		rc = 0;
 	}
 
+	if (rc)
+		goto out;
+
+	rc = tpm2_sessions_init(chip);
+
 out:
 	/*
 	 * Infineon TPM in field upgrade mode will return no data for the number

drivers/char/tpm/tpm2-space.c

@@ -68,8 +68,8 @@ void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space)
 	kfree(space->session_buf);
 }
 
-static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
-			     unsigned int *offset, u32 *handle)
+int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
+		      unsigned int *offset, u32 *handle)
 {
 	struct tpm_buf tbuf;
 	struct tpm2_context *ctx;
@@ -105,6 +105,9 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
 		*handle = 0;
 		tpm_buf_destroy(&tbuf);
 		return -ENOENT;
+	} else if (tpm2_rc_value(rc) == TPM2_RC_INTEGRITY) {
+		tpm_buf_destroy(&tbuf);
+		return -EINVAL;
 	} else if (rc > 0) {
 		dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
 			 __func__, rc);
@@ -119,8 +122,8 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
 	return 0;
 }
 
-static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
-			     unsigned int buf_size, unsigned int *offset)
+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;

drivers/char/tpm/tpm_infineon.c

@@ -51,34 +51,40 @@ static struct tpm_inf_dev tpm_dev;
 
 static inline void tpm_data_out(unsigned char data, unsigned char offset)
 {
+#ifdef CONFIG_HAS_IOPORT
 	if (tpm_dev.iotype == TPM_INF_IO_PORT)
 		outb(data, tpm_dev.data_regs + offset);
 	else
+#endif
 		writeb(data, tpm_dev.mem_base + tpm_dev.data_regs + offset);
 }
 
 static inline unsigned char tpm_data_in(unsigned char offset)
 {
+#ifdef CONFIG_HAS_IOPORT
 	if (tpm_dev.iotype == TPM_INF_IO_PORT)
 		return inb(tpm_dev.data_regs + offset);
-	else
-		return readb(tpm_dev.mem_base + tpm_dev.data_regs + offset);
+#endif
+	return readb(tpm_dev.mem_base + tpm_dev.data_regs + offset);
 }
 
 static inline void tpm_config_out(unsigned char data, unsigned char offset)
 {
+#ifdef CONFIG_HAS_IOPORT
 	if (tpm_dev.iotype == TPM_INF_IO_PORT)
 		outb(data, tpm_dev.config_port + offset);
 	else
+#endif
 		writeb(data, tpm_dev.mem_base + tpm_dev.index_off + offset);
 }
 
 static inline unsigned char tpm_config_in(unsigned char offset)
 {
+#ifdef CONFIG_HAS_IOPORT
 	if (tpm_dev.iotype == TPM_INF_IO_PORT)
 		return inb(tpm_dev.config_port + offset);
-	else
-		return readb(tpm_dev.mem_base + tpm_dev.index_off + offset);
+#endif
+	return readb(tpm_dev.mem_base + tpm_dev.index_off + offset);
 }
 
 /* TPM header definitions */

drivers/char/tpm/tpm_tis_core.c

@@ -1057,11 +1057,6 @@ static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value)
 		clkrun_val &= ~LPC_CLKRUN_EN;
 		iowrite32(clkrun_val, data->ilb_base_addr + LPC_CNTRL_OFFSET);
 
-		/*
-		 * Write any random value on port 0x80 which is on LPC, to make
-		 * sure LPC clock is running before sending any TPM command.
-		 */
-		outb(0xCC, 0x80);
 	} else {
 		data->clkrun_enabled--;
 		if (data->clkrun_enabled)
@@ -1072,13 +1067,15 @@ static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value)
 		/* Enable LPC CLKRUN# */
 		clkrun_val |= LPC_CLKRUN_EN;
 		iowrite32(clkrun_val, data->ilb_base_addr + LPC_CNTRL_OFFSET);
-
-		/*
-		 * Write any random value on port 0x80 which is on LPC, to make
-		 * sure LPC clock is running before sending any TPM command.
-		 */
-		outb(0xCC, 0x80);
 	}
+
+#ifdef CONFIG_HAS_IOPORT
+	/*
+	 * Write any random value on port 0x80 which is on LPC, to make
+	 * sure LPC clock is running before sending any TPM command.
+	 */
+	outb(0xCC, 0x80);
+#endif
 }
 
 static const struct tpm_class_ops tpm_tis = {

include/crypto/aes.h

@@ -87,4 +87,9 @@ void aes_decrypt(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);
 extern const u8 crypto_aes_sbox[];
 extern const u8 crypto_aes_inv_sbox[];
 
+void aescfb_encrypt(const struct crypto_aes_ctx *ctx, u8 *dst, const u8 *src,
+		    int len, const u8 iv[AES_BLOCK_SIZE]);
+void aescfb_decrypt(const struct crypto_aes_ctx *ctx, u8 *dst, const u8 *src,
+		    int len, const u8 iv[AES_BLOCK_SIZE]);
+
 #endif

include/keys/trusted_tpm.h

@@ -6,8 +6,6 @@
 #include <linux/tpm_command.h>
 
 /* implementation specific TPM constants */
-#define MAX_BUF_SIZE			1024
-#define TPM_GETRANDOM_SIZE		14
 #define TPM_SIZE_OFFSET			2
 #define TPM_RETURN_OFFSET		6
 #define TPM_DATA_OFFSET			10

lib/crypto/Kconfig

@@ -8,6 +8,11 @@ config CRYPTO_LIB_UTILS
 config CRYPTO_LIB_AES
 	tristate
 
+config CRYPTO_LIB_AESCFB
+	tristate
+	select CRYPTO_LIB_AES
+	select CRYPTO_LIB_UTILS
+
 config CRYPTO_LIB_AESGCM
 	tristate
 	select CRYPTO_LIB_AES

lib/crypto/Makefile

@@ -10,6 +10,9 @@ obj-$(CONFIG_CRYPTO_LIB_CHACHA_GENERIC)		+= libchacha.o
 obj-$(CONFIG_CRYPTO_LIB_AES)			+= libaes.o
 libaes-y					:= aes.o
 
+obj-$(CONFIG_CRYPTO_LIB_AESCFB)			+= libaescfb.o
+libaescfb-y					:= aescfb.o
+
 obj-$(CONFIG_CRYPTO_LIB_AESGCM)			+= libaesgcm.o
 libaesgcm-y					:= aesgcm.o
 

lib/crypto/aescfb.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Minimal library implementation of AES in CFB mode
+ *
+ * Copyright 2023 Google LLC
+ */
+
+#include <linux/module.h>
+
+#include <crypto/algapi.h>
+#include <crypto/aes.h>
+
+#include <asm/irqflags.h>
+
+static void aescfb_encrypt_block(const struct crypto_aes_ctx *ctx, void *dst,
+				 const void *src)
+{
+	unsigned long flags;
+
+	/*
+	 * In AES-CFB, the AES encryption operates on known 'plaintext' (the IV
+	 * and ciphertext), making it susceptible to timing attacks on the
+	 * encryption key. The AES library already mitigates this risk to some
+	 * extent by pulling the entire S-box into the caches before doing any
+	 * substitutions, but this strategy is more effective when running with
+	 * interrupts disabled.
+	 */
+	local_irq_save(flags);
+	aes_encrypt(ctx, dst, src);
+	local_irq_restore(flags);
+}
+
+/**
+ * aescfb_encrypt - Perform AES-CFB encryption on a block of data
+ *
+ * @ctx:	The AES-CFB key schedule
+ * @dst:	Pointer to the ciphertext output buffer
+ * @src:	Pointer the plaintext (may equal @dst for encryption in place)
+ * @len:	The size in bytes of the plaintext and ciphertext.
+ * @iv:		The initialization vector (IV) to use for this block of data
+ */
+void aescfb_encrypt(const struct crypto_aes_ctx *ctx, u8 *dst, const u8 *src,
+		    int len, const u8 iv[AES_BLOCK_SIZE])
+{
+	u8 ks[AES_BLOCK_SIZE];
+	const u8 *v = iv;
+
+	while (len > 0) {
+		aescfb_encrypt_block(ctx, ks, v);
+		crypto_xor_cpy(dst, src, ks, min(len, AES_BLOCK_SIZE));
+		v = dst;
+
+		dst += AES_BLOCK_SIZE;
+		src += AES_BLOCK_SIZE;
+		len -= AES_BLOCK_SIZE;
+	}
+
+	memzero_explicit(ks, sizeof(ks));
+}
+EXPORT_SYMBOL(aescfb_encrypt);
+
+/**
+ * aescfb_decrypt - Perform AES-CFB decryption on a block of data
+ *
+ * @ctx:	The AES-CFB key schedule
+ * @dst:	Pointer to the plaintext output buffer
+ * @src:	Pointer the ciphertext (may equal @dst for decryption in place)
+ * @len:	The size in bytes of the plaintext and ciphertext.
+ * @iv:		The initialization vector (IV) to use for this block of data
+ */
+void aescfb_decrypt(const struct crypto_aes_ctx *ctx, u8 *dst, const u8 *src,
+		    int len, const u8 iv[AES_BLOCK_SIZE])
+{
+	u8 ks[2][AES_BLOCK_SIZE];
+
+	aescfb_encrypt_block(ctx, ks[0], iv);
+
+	for (int i = 0; len > 0; i ^= 1) {
+		if (len > AES_BLOCK_SIZE)
+			/*
+			 * Generate the keystream for the next block before
+			 * performing the XOR, as that may update in place and
+			 * overwrite the ciphertext.
+			 */
+			aescfb_encrypt_block(ctx, ks[!i], src);
+
+		crypto_xor_cpy(dst, src, ks[i], min(len, AES_BLOCK_SIZE));
+
+		dst += AES_BLOCK_SIZE;
+		src += AES_BLOCK_SIZE;
+		len -= AES_BLOCK_SIZE;
+	}
+
+	memzero_explicit(ks, sizeof(ks));
+}
+EXPORT_SYMBOL(aescfb_decrypt);
+
+MODULE_DESCRIPTION("Generic AES-CFB library");
+MODULE_AUTHOR("Ard Biesheuvel <ardb@kernel.org>");
+MODULE_LICENSE("GPL");
+
+#ifndef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
+
+/*
+ * Test code below. Vectors taken from crypto/testmgr.h
+ */
+
+static struct {
+	u8	ptext[64];
+	u8	ctext[64];
+
+	u8	key[AES_MAX_KEY_SIZE];
+	u8	iv[AES_BLOCK_SIZE];
+
+	int	klen;
+	int	len;
+} const aescfb_tv[] __initconst = {
+	{ /* From NIST SP800-38A */
+		.key    = "\x2b\x7e\x15\x16\x28\xae\xd2\xa6"
+			  "\xab\xf7\x15\x88\x09\xcf\x4f\x3c",
+		.klen	= 16,
+		.iv	= "\x00\x01\x02\x03\x04\x05\x06\x07"
+			  "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f",
+		.ptext	= "\x6b\xc1\xbe\xe2\x2e\x40\x9f\x96"
+			  "\xe9\x3d\x7e\x11\x73\x93\x17\x2a"
+			  "\xae\x2d\x8a\x57\x1e\x03\xac\x9c"
+			  "\x9e\xb7\x6f\xac\x45\xaf\x8e\x51"
+			  "\x30\xc8\x1c\x46\xa3\x5c\xe4\x11"
+			  "\xe5\xfb\xc1\x19\x1a\x0a\x52\xef"
+			  "\xf6\x9f\x24\x45\xdf\x4f\x9b\x17"
+			  "\xad\x2b\x41\x7b\xe6\x6c\x37\x10",
+		.ctext	= "\x3b\x3f\xd9\x2e\xb7\x2d\xad\x20"
+			  "\x33\x34\x49\xf8\xe8\x3c\xfb\x4a"
+			  "\xc8\xa6\x45\x37\xa0\xb3\xa9\x3f"
+			  "\xcd\xe3\xcd\xad\x9f\x1c\xe5\x8b"
+			  "\x26\x75\x1f\x67\xa3\xcb\xb1\x40"
+			  "\xb1\x80\x8c\xf1\x87\xa4\xf4\xdf"
+			  "\xc0\x4b\x05\x35\x7c\x5d\x1c\x0e"
+			  "\xea\xc4\xc6\x6f\x9f\xf7\xf2\xe6",
+		.len	= 64,
+	}, {
+		.key	= "\x8e\x73\xb0\xf7\xda\x0e\x64\x52"
+			  "\xc8\x10\xf3\x2b\x80\x90\x79\xe5"
+			  "\x62\xf8\xea\xd2\x52\x2c\x6b\x7b",
+		.klen	= 24,
+		.iv	= "\x00\x01\x02\x03\x04\x05\x06\x07"
+			  "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f",
+		.ptext	= "\x6b\xc1\xbe\xe2\x2e\x40\x9f\x96"
+			  "\xe9\x3d\x7e\x11\x73\x93\x17\x2a"
+			  "\xae\x2d\x8a\x57\x1e\x03\xac\x9c"
+			  "\x9e\xb7\x6f\xac\x45\xaf\x8e\x51"
+			  "\x30\xc8\x1c\x46\xa3\x5c\xe4\x11"
+			  "\xe5\xfb\xc1\x19\x1a\x0a\x52\xef"
+			  "\xf6\x9f\x24\x45\xdf\x4f\x9b\x17"
+			  "\xad\x2b\x41\x7b\xe6\x6c\x37\x10",
+		.ctext	= "\xcd\xc8\x0d\x6f\xdd\xf1\x8c\xab"
+			  "\x34\xc2\x59\x09\xc9\x9a\x41\x74"
+			  "\x67\xce\x7f\x7f\x81\x17\x36\x21"
+			  "\x96\x1a\x2b\x70\x17\x1d\x3d\x7a"
+			  "\x2e\x1e\x8a\x1d\xd5\x9b\x88\xb1"
+			  "\xc8\xe6\x0f\xed\x1e\xfa\xc4\xc9"
+			  "\xc0\x5f\x9f\x9c\xa9\x83\x4f\xa0"
+			  "\x42\xae\x8f\xba\x58\x4b\x09\xff",
+		.len	= 64,
+	}, {
+		.key	= "\x60\x3d\xeb\x10\x15\xca\x71\xbe"
+			  "\x2b\x73\xae\xf0\x85\x7d\x77\x81"
+			  "\x1f\x35\x2c\x07\x3b\x61\x08\xd7"
+			  "\x2d\x98\x10\xa3\x09\x14\xdf\xf4",
+		.klen	= 32,
+		.iv	= "\x00\x01\x02\x03\x04\x05\x06\x07"
+			  "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f",
+		.ptext	= "\x6b\xc1\xbe\xe2\x2e\x40\x9f\x96"
+			  "\xe9\x3d\x7e\x11\x73\x93\x17\x2a"
+			  "\xae\x2d\x8a\x57\x1e\x03\xac\x9c"
+			  "\x9e\xb7\x6f\xac\x45\xaf\x8e\x51"
+			  "\x30\xc8\x1c\x46\xa3\x5c\xe4\x11"
+			  "\xe5\xfb\xc1\x19\x1a\x0a\x52\xef"
+			  "\xf6\x9f\x24\x45\xdf\x4f\x9b\x17"
+			  "\xad\x2b\x41\x7b\xe6\x6c\x37\x10",
+		.ctext	= "\xdc\x7e\x84\xbf\xda\x79\x16\x4b"
+			  "\x7e\xcd\x84\x86\x98\x5d\x38\x60"
+			  "\x39\xff\xed\x14\x3b\x28\xb1\xc8"
+			  "\x32\x11\x3c\x63\x31\xe5\x40\x7b"
+			  "\xdf\x10\x13\x24\x15\xe5\x4b\x92"
+			  "\xa1\x3e\xd0\xa8\x26\x7a\xe2\xf9"
+			  "\x75\xa3\x85\x74\x1a\xb9\xce\xf8"
+			  "\x20\x31\x62\x3d\x55\xb1\xe4\x71",
+		.len	= 64,
+	}, { /* > 16 bytes, not a multiple of 16 bytes */
+		.key	= "\x2b\x7e\x15\x16\x28\xae\xd2\xa6"
+			  "\xab\xf7\x15\x88\x09\xcf\x4f\x3c",
+		.klen	= 16,
+		.iv	= "\x00\x01\x02\x03\x04\x05\x06\x07"
+			  "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f",
+		.ptext	= "\x6b\xc1\xbe\xe2\x2e\x40\x9f\x96"
+			  "\xe9\x3d\x7e\x11\x73\x93\x17\x2a"
+			  "\xae",
+		.ctext	= "\x3b\x3f\xd9\x2e\xb7\x2d\xad\x20"
+			  "\x33\x34\x49\xf8\xe8\x3c\xfb\x4a"
+			  "\xc8",
+		.len	= 17,
+	}, { /* < 16 bytes */
+		.key	= "\x2b\x7e\x15\x16\x28\xae\xd2\xa6"
+			  "\xab\xf7\x15\x88\x09\xcf\x4f\x3c",
+		.klen	= 16,
+		.iv	= "\x00\x01\x02\x03\x04\x05\x06\x07"
+			  "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f",
+		.ptext	= "\x6b\xc1\xbe\xe2\x2e\x40\x9f",
+		.ctext	= "\x3b\x3f\xd9\x2e\xb7\x2d\xad",
+		.len	= 7,
+	},
+};
+
+static int __init libaescfb_init(void)
+{
+	for (int i = 0; i < ARRAY_SIZE(aescfb_tv); i++) {
+		struct crypto_aes_ctx ctx;
+		u8 buf[64];
+
+		if (aes_expandkey(&ctx, aescfb_tv[i].key, aescfb_tv[i].klen)) {
+			pr_err("aes_expandkey() failed on vector %d\n", i);
+			return -ENODEV;
+		}
+
+		aescfb_encrypt(&ctx, buf, aescfb_tv[i].ptext, aescfb_tv[i].len,
+			       aescfb_tv[i].iv);
+		if (memcmp(buf, aescfb_tv[i].ctext, aescfb_tv[i].len)) {
+			pr_err("aescfb_encrypt() #1 failed on vector %d\n", i);
+			return -ENODEV;
+		}
+
+		/* decrypt in place */
+		aescfb_decrypt(&ctx, buf, buf, aescfb_tv[i].len, aescfb_tv[i].iv);
+		if (memcmp(buf, aescfb_tv[i].ptext, aescfb_tv[i].len)) {
+			pr_err("aescfb_decrypt() failed on vector %d\n", i);
+			return -ENODEV;
+		}
+
+		/* encrypt in place */
+		aescfb_encrypt(&ctx, buf, buf, aescfb_tv[i].len, aescfb_tv[i].iv);
+		if (memcmp(buf, aescfb_tv[i].ctext, aescfb_tv[i].len)) {
+			pr_err("aescfb_encrypt() #2 failed on vector %d\n", i);
+
+			return -ENODEV;
+		}
+
+	}
+	return 0;
+}
+module_init(libaescfb_init);
+
+static void __exit libaescfb_exit(void)
+{
+}
+module_exit(libaescfb_exit);
+#endif

security/keys/trusted-keys/trusted_tpm1.c

@@ -356,17 +356,28 @@ static int TSS_checkhmac2(unsigned char *buffer,
  */
 int trusted_tpm_send(unsigned char *cmd, size_t buflen)
 {
+	struct tpm_buf buf;
 	int rc;
 
 	if (!chip)
 		return -ENODEV;
 
+	rc = tpm_try_get_ops(chip);
+	if (rc)
+		return rc;
+
+	buf.flags = 0;
+	buf.length = buflen;
+	buf.data = cmd;
 	dump_tpm_buf(cmd);
-	rc = tpm_send(chip, cmd, buflen);
+	rc = tpm_transmit_cmd(chip, &buf, 4, "sending data");
 	dump_tpm_buf(cmd);
+
 	if (rc > 0)
-		/* Can't return positive return codes values to keyctl */
+		/* TPM error */
 		rc = -EPERM;
+
+	tpm_put_ops(chip);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(trusted_tpm_send);
@@ -407,7 +418,7 @@ static int osap(struct tpm_buf *tb, struct osapsess *s,
 	tpm_buf_append_u32(tb, handle);
 	tpm_buf_append(tb, ononce, TPM_NONCE_SIZE);
 
-	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	ret = trusted_tpm_send(tb->data, tb->length);
 	if (ret < 0)
 		return ret;
 
@@ -431,7 +442,7 @@ int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce)
 		return -ENODEV;
 
 	tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OIAP);
-	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	ret = trusted_tpm_send(tb->data, tb->length);
 	if (ret < 0)
 		return ret;
 
@@ -543,7 +554,7 @@ static int tpm_seal(struct tpm_buf *tb, uint16_t keytype,
 	tpm_buf_append_u8(tb, cont);
 	tpm_buf_append(tb, td->pubauth, SHA1_DIGEST_SIZE);
 
-	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	ret = trusted_tpm_send(tb->data, tb->length);
 	if (ret < 0)
 		goto out;
 
@@ -634,7 +645,7 @@ static int tpm_unseal(struct tpm_buf *tb,
 	tpm_buf_append_u8(tb, cont);
 	tpm_buf_append(tb, authdata2, SHA1_DIGEST_SIZE);
 
-	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	ret = trusted_tpm_send(tb->data, tb->length);
 	if (ret < 0) {
 		pr_info("authhmac failed (%d)\n", ret);
 		return ret;

security/keys/trusted-keys/trusted_tpm2.c

@@ -228,8 +228,9 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
 		      struct trusted_key_payload *payload,
 		      struct trusted_key_options *options)
 {
+	off_t offset = TPM_HEADER_SIZE;
+	struct tpm_buf buf, sized;
 	int blob_len = 0;
-	struct tpm_buf buf;
 	u32 hash;
 	u32 flags;
 	int i;
@@ -252,50 +253,58 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
 	if (rc)
 		return rc;
 
+	rc = tpm2_start_auth_session(chip);
+	if (rc)
+		goto out_put;
+
 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
 	if (rc) {
-		tpm_put_ops(chip);
-		return rc;
+		tpm2_end_auth_session(chip);
+		goto out_put;
 	}
 
-	tpm_buf_append_u32(&buf, options->keyhandle);
-	tpm2_buf_append_auth(&buf, TPM2_RS_PW,
-			     NULL /* nonce */, 0,
-			     0 /* session_attributes */,
-			     options->keyauth /* hmac */,
-			     TPM_DIGEST_SIZE);
+	rc = tpm_buf_init_sized(&sized);
+	if (rc) {
+		tpm_buf_destroy(&buf);
+		tpm2_end_auth_session(chip);
+		goto out_put;
+	}
+
+	tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
+	tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_DECRYPT,
+				    options->keyauth, TPM_DIGEST_SIZE);
 
 	/* sensitive */
-	tpm_buf_append_u16(&buf, 4 + options->blobauth_len + payload->key_len);
+	tpm_buf_append_u16(&sized, options->blobauth_len);
 
-	tpm_buf_append_u16(&buf, options->blobauth_len);
 	if (options->blobauth_len)
-		tpm_buf_append(&buf, options->blobauth, options->blobauth_len);
+		tpm_buf_append(&sized, options->blobauth, options->blobauth_len);
 
-	tpm_buf_append_u16(&buf, payload->key_len);
-	tpm_buf_append(&buf, payload->key, payload->key_len);
+	tpm_buf_append_u16(&sized, payload->key_len);
+	tpm_buf_append(&sized, payload->key, payload->key_len);
+	tpm_buf_append(&buf, sized.data, sized.length);
 
 	/* public */
-	tpm_buf_append_u16(&buf, 14 + options->policydigest_len);
-	tpm_buf_append_u16(&buf, TPM_ALG_KEYEDHASH);
-	tpm_buf_append_u16(&buf, hash);
+	tpm_buf_reset_sized(&sized);
+	tpm_buf_append_u16(&sized, TPM_ALG_KEYEDHASH);
+	tpm_buf_append_u16(&sized, hash);
 
 	/* key properties */
 	flags = 0;
 	flags |= options->policydigest_len ? 0 : TPM2_OA_USER_WITH_AUTH;
-	flags |= payload->migratable ? 0 : (TPM2_OA_FIXED_TPM |
-					    TPM2_OA_FIXED_PARENT);
-	tpm_buf_append_u32(&buf, flags);
+	flags |= payload->migratable ? 0 : (TPM2_OA_FIXED_TPM | TPM2_OA_FIXED_PARENT);
+	tpm_buf_append_u32(&sized, flags);
 
 	/* policy */
-	tpm_buf_append_u16(&buf, options->policydigest_len);
+	tpm_buf_append_u16(&sized, options->policydigest_len);
 	if (options->policydigest_len)
-		tpm_buf_append(&buf, options->policydigest,
-			       options->policydigest_len);
+		tpm_buf_append(&sized, options->policydigest, options->policydigest_len);
 
 	/* public parameters */
-	tpm_buf_append_u16(&buf, TPM_ALG_NULL);
-	tpm_buf_append_u16(&buf, 0);
+	tpm_buf_append_u16(&sized, TPM_ALG_NULL);
+	tpm_buf_append_u16(&sized, 0);
+
+	tpm_buf_append(&buf, sized.data, sized.length);
 
 	/* outside info */
 	tpm_buf_append_u16(&buf, 0);
@@ -305,28 +314,30 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
 
 	if (buf.flags & TPM_BUF_OVERFLOW) {
 		rc = -E2BIG;
+		tpm2_end_auth_session(chip);
 		goto out;
 	}
 
+	tpm_buf_fill_hmac_session(chip, &buf);
 	rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data");
+	rc = tpm_buf_check_hmac_response(chip, &buf, rc);
 	if (rc)
 		goto out;
 
-	blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
-	if (blob_len > MAX_BLOB_SIZE) {
+	blob_len = tpm_buf_read_u32(&buf, &offset);
+	if (blob_len > MAX_BLOB_SIZE || buf.flags & TPM_BUF_BOUNDARY_ERROR) {
 		rc = -E2BIG;
 		goto out;
 	}
-	if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 4 + blob_len) {
+	if (buf.length - offset < blob_len) {
 		rc = -EFAULT;
 		goto out;
 	}
 
-	blob_len = tpm2_key_encode(payload, options,
-				   &buf.data[TPM_HEADER_SIZE + 4],
-				   blob_len);
+	blob_len = tpm2_key_encode(payload, options, &buf.data[offset], blob_len);
 
 out:
+	tpm_buf_destroy(&sized);
 	tpm_buf_destroy(&buf);
 
 	if (rc > 0) {
@@ -340,6 +351,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
 	else
 		payload->blob_len = blob_len;
 
+out_put:
 	tpm_put_ops(chip);
 	return rc;
 }
@@ -409,25 +421,31 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
 	if (blob_len > payload->blob_len)
 		return -E2BIG;
 
-	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
+	rc = tpm2_start_auth_session(chip);
 	if (rc)
 		return rc;
 
-	tpm_buf_append_u32(&buf, options->keyhandle);
-	tpm2_buf_append_auth(&buf, TPM2_RS_PW,
-			     NULL /* nonce */, 0,
-			     0 /* session_attributes */,
-			     options->keyauth /* hmac */,
-			     TPM_DIGEST_SIZE);
+	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
+	if (rc) {
+		tpm2_end_auth_session(chip);
+		return rc;
+	}
+
+	tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
+	tpm_buf_append_hmac_session(chip, &buf, 0, options->keyauth,
+				    TPM_DIGEST_SIZE);
 
 	tpm_buf_append(&buf, blob, blob_len);
 
 	if (buf.flags & TPM_BUF_OVERFLOW) {
 		rc = -E2BIG;
+		tpm2_end_auth_session(chip);
 		goto out;
 	}
 
+	tpm_buf_fill_hmac_session(chip, &buf);
 	rc = tpm_transmit_cmd(chip, &buf, 4, "loading blob");
+	rc = tpm_buf_check_hmac_response(chip, &buf, rc);
 	if (!rc)
 		*blob_handle = be32_to_cpup(
 			(__be32 *) &buf.data[TPM_HEADER_SIZE]);
@@ -465,20 +483,44 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
 	u8 *data;
 	int rc;
 
-	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
+	rc = tpm2_start_auth_session(chip);
 	if (rc)
 		return rc;
 
-	tpm_buf_append_u32(&buf, blob_handle);
-	tpm2_buf_append_auth(&buf,
-			     options->policyhandle ?
-			     options->policyhandle : TPM2_RS_PW,
-			     NULL /* nonce */, 0,
-			     TPM2_SA_CONTINUE_SESSION,
-			     options->blobauth /* hmac */,
-			     options->blobauth_len);
+	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
+	if (rc) {
+		tpm2_end_auth_session(chip);
+		return rc;
+	}
+
+	tpm_buf_append_name(chip, &buf, blob_handle, NULL);
+
+	if (!options->policyhandle) {
+		tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT,
+					    options->blobauth,
+					    options->blobauth_len);
+	} else {
+		/*
+		 * FIXME: The policy session was generated outside the
+		 * kernel so we don't known the nonce and thus can't
+		 * calculate a HMAC on it.  Therefore, the user can
+		 * only really use TPM2_PolicyPassword and we must
+		 * send down the plain text password, which could be
+		 * intercepted.  We can still encrypt the returned
+		 * key, but that's small comfort since the interposer
+		 * could repeat our actions with the exfiltrated
+		 * password.
+		 */
+		tpm2_buf_append_auth(&buf, options->policyhandle,
+				     NULL /* nonce */, 0, 0,
+				     options->blobauth, options->blobauth_len);
+		tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT,
+						NULL, 0);
+	}
 
+	tpm_buf_fill_hmac_session(chip, &buf);
 	rc = tpm_transmit_cmd(chip, &buf, 6, "unsealing");
+	rc = tpm_buf_check_hmac_response(chip, &buf, rc);
 	if (rc > 0)
 		rc = -EPERM;