[PATCH RFC v2 3/5] tpm: infrastructure for TPM spaces

From: Jarkko Sakkinen
Date: Thu Jan 12 2017 - 12:49:09 EST

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@xxxxxxxxxxxxxxx>
---
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 | 61 ++++----
drivers/char/tpm/tpm-sysfs.c | 2 +-
drivers/char/tpm/tpm.h | 22 ++-
drivers/char/tpm/tpm2-cmd.c | 34 +++--
drivers/char/tpm/tpm2-space.c | 298 +++++++++++++++++++++++++++++++++++++++
8 files changed, 382 insertions(+), 46 deletions(-)
create mode 100644 drivers/char/tpm/tpm2-space.c

diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index a05b1eb..251d0ed 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -3,7 +3,7 @@
#
obj-$(CONFIG_TCG_TPM) += tpm.o
tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
- tpm_eventlog.o
+ tpm_eventlog.o tpm2-space.o
tpm-$(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 912ad30..249eeb0 100644
--- a/drivers/char/tpm/tpm-dev.c
+++ b/drivers/char/tpm/tpm-dev.c
@@ -144,7 +144,7 @@ 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 0c5aba1..65fcd04c 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -370,10 +370,11 @@ 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;

@@ -399,10 +400,14 @@ 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, bufsiz);
+ 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;
}

@@ -435,17 +440,23 @@ 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, bufsiz);
+
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;
}

/**
@@ -463,13 +474,14 @@ 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 *cmd,
- int len, unsigned int flags, const char *desc)
+ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
+ void *cmd, int len, unsigned int flags,
+ const char *desc)
{
const struct tpm_output_header *header;
int err;

- len = tpm_transmit(chip, (const u8 *)cmd, len, flags);
+ len = tpm_transmit(chip, space, cmd, len, flags);
if (len < 0)
return len;
else if (len < TPM_HEADER_SIZE)
@@ -521,7 +533,7 @@ 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, 0,
+ rc = tpm_transmit_cmd(chip, NULL, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
desc);
if (!rc)
*cap = tpm_cmd.params.getcap_out.cap;
@@ -545,8 +557,9 @@ 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,
- "attempting to start the TPM");
+ return tpm_transmit_cmd(chip, NULL, &start_cmd,
+ TPM_INTERNAL_RESULT_SIZE,
+ 0, "attempting to start the TPM");
}

int tpm_get_timeouts(struct tpm_chip *chip)
@@ -687,8 +700,8 @@ 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,
- "continue selftest");
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
+ 0, "continue selftest");
return rc;
}

@@ -707,7 +720,7 @@ 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, 0,
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE, 0,
"attempting to read a pcr value");

if (rc == 0)
@@ -805,7 +818,7 @@ 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, 0,
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, EXTEND_PCR_RESULT_SIZE, 0,
"attempting extend a PCR value");

tpm_put_ops(chip);
@@ -909,7 +922,7 @@ int tpm_send(u32 chip_num, void *cmd, size_t buflen)
if (chip == NULL)
return -ENODEV;

- rc = tpm_transmit_cmd(chip, cmd, buflen, 0, "attempting tpm_cmd");
+ rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, "attempting tpm_cmd");

tpm_put_ops(chip);
return rc;
@@ -1011,15 +1024,15 @@ 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, 0,
- "extending dummy pcr before suspend");
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, EXTEND_PCR_RESULT_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,
- NULL);
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
+ 0, NULL);

/*
* If the TPM indicates that it is too busy to respond to
@@ -1102,7 +1115,7 @@ 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,
0, "attempting get random");
if (err)
diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index 848ad65..dd31a00 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -39,7 +39,7 @@ 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, 0,
+ err = tpm_transmit_cmd(chip, NULL, &tpm_cmd, READ_PUBEK_RESULT_SIZE, 0,
"attempting to read the PUBEK");
if (err)
goto out;
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index c87c221..0e93b93 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -91,6 +91,7 @@ enum tpm2_structures {

enum tpm2_return_codes {
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 */
@@ -114,6 +115,8 @@ 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,
@@ -151,6 +154,11 @@ enum tpm2_cc_attrs {

#define TPM_PPI_VERSION_LEN 3

+struct tpm_space {
+ u32 context_tbl[14];
+ u8 *context_buf;
+};
+
enum tpm_chip_flags {
TPM_CHIP_FLAG_TPM2 = BIT(1),
TPM_CHIP_FLAG_IRQ = BIT(2),
@@ -202,6 +210,7 @@ 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;
};
@@ -509,10 +518,11 @@ 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 *cmd, int len,
- unsigned int flags, const char *desc);
+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,
+ void *cmd, int len, unsigned int flags,
+ const char *desc);
ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
const char *desc);
int tpm_get_timeouts(struct tpm_chip *);
@@ -566,4 +576,8 @@ 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);
bool tpm2_find_cc_attrs(struct tpm_chip *chip, u32 cc, u32 *attrs);
+int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space,
+ u32 cc, u8 *buf, size_t bufsiz);
+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 e2b4c75..6842555 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -280,7 +280,7 @@ 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), 0,
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0,
"attempting to read a pcr value");
if (rc == 0) {
buf = cmd.params.pcrread_out.digest;
@@ -327,7 +327,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
cmd.params.pcrextend_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
memcpy(cmd.params.pcrextend_in.digest, hash, TPM_DIGEST_SIZE);

- rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0,
"attempting extend a PCR value");

return rc;
@@ -373,7 +373,7 @@ 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), 0,
+ err = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0,
"attempting get random");
if (err)
break;
@@ -423,8 +423,8 @@ void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,

tpm_buf_append_u32(&buf, handle);

- rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags,
- "flushing context");
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, TPM_BUFSIZE, flags,
+ "flushing context");
if (rc)
dev_warn(&chip->dev, "0x%08x was not flushed, rc=%d\n", handle,
rc);
@@ -542,7 +542,8 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
goto out;
}

- rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, "sealing data");
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, TPM_BUFSIZE, 0,
+ "sealing data");
if (rc)
goto out;

@@ -620,7 +621,8 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
goto out;
}

- rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags, "loading blob");
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, TPM_BUFSIZE, flags,
+ "loading blob");
if (!rc)
*blob_handle = be32_to_cpup(
(__be32 *) &buf.data[TPM_HEADER_SIZE]);
@@ -670,7 +672,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
options->blobauth /* hmac */,
TPM_DIGEST_SIZE);

- rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags, "unsealing");
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, TPM_BUFSIZE, flags,
+ "unsealing");
if (rc > 0)
rc = -EPERM;

@@ -738,7 +741,7 @@ 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), 0, desc);
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, desc);
if (!rc)
*value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);

@@ -772,7 +775,7 @@ 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,
+ return tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0,
"attempting to start the TPM");
}

@@ -801,7 +804,8 @@ 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, "stopping the TPM");
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0,
+ "stopping the TPM");

/* In places where shutdown command is sent there's no much we can do
* except print the error code on a system failure.
@@ -864,7 +868,7 @@ 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,
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, TPM2_SELF_TEST_IN_SIZE, 0,
"continue selftest");

/* At least some prototype chips seem to give RC_TESTING error
@@ -915,7 +919,7 @@ 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, NULL);
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, NULL);
if (rc < 0)
break;

@@ -948,7 +952,7 @@ 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, NULL);
+ rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, NULL);
if (rc < 0)
return rc;

@@ -1010,7 +1014,7 @@ int tpm2_auto_startup(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, 0, NULL);
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, NULL);
if (rc < 0) {
tpm_buf_destroy(&buf);
goto out;
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
new file mode 100644
index 0000000..ca55feb
--- /dev/null
+++ b/drivers/char/tpm/tpm2-space.c
@@ -0,0 +1,298 @@
+/*
+ * Copyright (C) 2016 Intel Corporation
+ *
+ * Authors:
+ * Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
+ *
+ * Maintained by: <tpmdd-devel@xxxxxxxxxxxxxxxxxxxxx>
+ *
+ * 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 "tpm.h"
+
+enum tpm2_handle_types {
+ TPM2_HT_HMAC_SESSION = 0x02000000,
+ TPM2_HT_POLICY_SESSION = 0x03000000,
+ TPM2_HT_TRANSIENT = 0x80000000,
+};
+
+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);
+}
+
+struct tpm2_context {
+ __be64 sequence;
+ __be32 saved_handle;
+ __be32 hierarchy;
+ __be16 blob_size;
+} __packed;
+
+static int tpm2_load_space(struct tpm_chip *chip)
+{
+ struct tpm_space *space = &chip->work_space;
+ struct tpm2_context *ctx;
+ struct tpm_buf buf;
+ int i;
+ int j;
+ int rc;
+ u32 s;
+
+ for (i = 0, j = 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 = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS,
+ TPM2_CC_CONTEXT_LOAD);
+ if (rc)
+ return rc;
+
+ ctx = (struct tpm2_context *)&space->context_buf[j];
+ s = sizeof(*ctx) + be16_to_cpu(ctx->blob_size);
+ tpm_buf_append(&buf, &space->context_buf[j], s);
+
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
+ TPM_TRANSMIT_UNLOCKED, NULL);
+ if (rc) {
+ dev_warn(&chip->dev, "%s: loading failed with %d\n",
+ __func__, rc);
+ rc = -EFAULT;
+ goto out_err;
+ }
+
+ space->context_tbl[i] =
+ be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE]);
+
+ j += s;
+
+ tpm_buf_destroy(&buf);
+ }
+
+ return 0;
+
+out_err:
+ tpm_buf_destroy(&buf);
+ tpm2_flush_space(chip);
+ return rc;
+}
+
+static int tpm2_map_command(struct tpm_chip *chip, u32 cc, u8 *cmd, size_t len)
+{
+ struct tpm_space *space = &chip->work_space;
+ unsigned int nr_handles;
+ u32 vhandle;
+ u32 phandle;
+ u32 attrs;
+ int i;
+ int j;
+ int rc;
+
+ if (!tpm2_find_cc_attrs(chip, cc, &attrs)) {
+ rc = -EINVAL;
+ goto out_err;
+ }
+
+ nr_handles = (attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0);
+
+ for (i = 0; i < nr_handles; i++) {
+ vhandle = be32_to_cpup((__be32 *)&cmd[TPM_HEADER_SIZE + 4 * i]);
+ if ((vhandle & 0xFF000000) != TPM2_HT_TRANSIENT)
+ continue;
+
+ j = 0xFFFFFF - (vhandle & 0xFFFFFF);
+ if (j > ARRAY_SIZE(space->context_tbl) ||
+ !space->context_tbl[j]) {
+ rc = -EINVAL;
+ goto out_err;
+ }
+
+ phandle = space->context_tbl[j];
+ *((__be32 *)&cmd[TPM_HEADER_SIZE + 4 * i]) =
+ cpu_to_be32(phandle);
+ }
+
+ return 0;
+
+out_err:
+ tpm2_flush_space(chip);
+ return rc;
+}
+
+int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space,
+ u32 cc, u8 *buf, size_t bufsiz)
+{
+ 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)
+ return rc;
+
+ rc = tpm2_map_command(chip, cc, buf, bufsiz);
+ if (rc)
+ 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;
+ int i;
+ int rc;
+
+ if (!tpm2_find_cc_attrs(chip, cc, &attrs)) {
+ /* should never happen */
+ dev_err(&chip->dev, "TPM returned a different CC: 0x%04x\n",
+ cc);
+ rc = -EFAULT;
+ goto out_err;
+ }
+
+ 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);
+ rc = -ENOMEM;
+ goto out_err;
+ }
+
+ space->context_tbl[i] = phandle;
+ vhandle = TPM2_HT_TRANSIENT | (0xFFFFFF - i);
+ *(__be32 *)&rsp[TPM_HEADER_SIZE] = cpu_to_be32(vhandle);
+
+ return 0;
+
+out_err:
+ tpm2_flush_space(chip);
+ return rc;
+}
+
+static int tpm2_save_space(struct tpm_chip *chip)
+{
+ struct tpm_space *space = &chip->work_space;
+ struct tpm_buf buf;
+ int i;
+ int j;
+ int rc;
+ u32 s;
+
+ for (i = 0, j = 0; i < ARRAY_SIZE(space->context_tbl); i++) {
+ if (!(space->context_tbl[i] && ~space->context_tbl[i]))
+ continue;
+
+ rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS,
+ TPM2_CC_CONTEXT_SAVE);
+ if (rc)
+ return rc;
+
+ tpm_buf_append_u32(&buf, space->context_tbl[i]);
+
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
+ TPM_TRANSMIT_UNLOCKED, NULL);
+ if ((rc & TPM2_RC_HANDLE) == TPM2_RC_HANDLE) {
+ space->context_tbl[i] = 0;
+ continue;
+ } else if (rc) {
+ dev_warn(&chip->dev, "%s: saving failed with %d\n",
+ __func__, rc);
+ rc = -EFAULT;
+ goto out_err;
+ }
+
+ s = tpm_buf_length(&buf) - TPM_HEADER_SIZE;
+ if ((j + s) > PAGE_SIZE) {
+ dev_warn(&chip->dev, "%s: out of backing storage\n",
+ __func__);
+ rc = -ENOMEM;
+ goto out_err;
+ }
+
+ memcpy(&space->context_buf[j], &buf.data[TPM_HEADER_SIZE], s);
+
+ tpm2_flush_context_cmd(chip, space->context_tbl[i],
+ TPM_TRANSMIT_UNLOCKED);
+
+ space->context_tbl[i] = ~0;
+
+ j += s;
+
+ tpm_buf_destroy(&buf);
+ }
+
+ return 0;
+out_err:
+ tpm_buf_destroy(&buf);
+ tpm2_flush_space(chip);
+ return rc;
+}
+
+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)
+ return rc;
+
+ rc = tpm2_save_space(chip);
+ if (rc)
+ 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