[PATCH 3/6] tpm: infrastructure for TPM spaces
From: Jarkko Sakkinen
Date: Wed Feb 08 2017 - 06:11:13 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 | 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@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 <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