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path: root/drivers/char/tpm/tpm-interface.c
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Diffstat (limited to 'drivers/char/tpm/tpm-interface.c')
-rw-r--r--drivers/char/tpm/tpm-interface.c163
1 files changed, 103 insertions, 60 deletions
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 586ca10b0d72..f745a098908b 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -52,12 +52,43 @@ MODULE_PARM_DESC(suspend_pcr,
unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
{
if (chip->flags & TPM_CHIP_FLAG_TPM2)
- return tpm2_calc_ordinal_duration(chip, ordinal);
+ return tpm2_calc_ordinal_duration(ordinal);
else
return tpm1_calc_ordinal_duration(chip, ordinal);
}
EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
+static void tpm_chip_cancel(struct tpm_chip *chip)
+{
+ if (!chip->ops->cancel)
+ return;
+
+ chip->ops->cancel(chip);
+}
+
+static u8 tpm_chip_status(struct tpm_chip *chip)
+{
+ if (!chip->ops->status)
+ return 0;
+
+ return chip->ops->status(chip);
+}
+
+static bool tpm_chip_req_canceled(struct tpm_chip *chip, u8 status)
+{
+ if (!chip->ops->req_canceled)
+ return false;
+
+ return chip->ops->req_canceled(chip, status);
+}
+
+static bool tpm_transmit_completed(u8 status, struct tpm_chip *chip)
+{
+ u8 status_masked = status & chip->ops->req_complete_mask;
+
+ return status_masked == chip->ops->req_complete_val;
+}
+
static ssize_t tpm_try_transmit(struct tpm_chip *chip, void *buf, size_t bufsiz)
{
struct tpm_header *header = buf;
@@ -82,7 +113,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, void *buf, size_t bufsiz)
return -E2BIG;
}
- rc = chip->ops->send(chip, buf, count);
+ rc = chip->ops->send(chip, buf, bufsiz, count);
if (rc < 0) {
if (rc != -EPIPE)
dev_err(&chip->dev,
@@ -90,8 +121,19 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, void *buf, size_t bufsiz)
return rc;
}
- /* A sanity check. send() should just return zero on success e.g.
- * not the command length.
+ /*
+ * Synchronous devices return the response directly during the send()
+ * call in the same buffer.
+ */
+ if (chip->flags & TPM_CHIP_FLAG_SYNC) {
+ len = rc;
+ rc = 0;
+ goto out_sync;
+ }
+
+ /*
+ * A sanity check. send() of asynchronous devices should just return
+ * zero on success e.g. not the command length.
*/
if (rc > 0) {
dev_warn(&chip->dev,
@@ -104,12 +146,11 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, void *buf, size_t bufsiz)
stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
do {
- u8 status = chip->ops->status(chip);
- if ((status & chip->ops->req_complete_mask) ==
- chip->ops->req_complete_val)
+ u8 status = tpm_chip_status(chip);
+ if (tpm_transmit_completed(status, chip))
goto out_recv;
- if (chip->ops->req_canceled(chip, status)) {
+ if (tpm_chip_req_canceled(chip, status)) {
dev_err(&chip->dev, "Operation Canceled\n");
return -ECANCELED;
}
@@ -118,7 +159,14 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, void *buf, size_t bufsiz)
rmb();
} while (time_before(jiffies, stop));
- chip->ops->cancel(chip);
+ /*
+ * Check for completion one more time, just in case the device reported
+ * it while the driver was sleeping in the busy loop above.
+ */
+ if (tpm_transmit_completed(tpm_chip_status(chip), chip))
+ goto out_recv;
+
+ tpm_chip_cancel(chip);
dev_err(&chip->dev, "Operation Timed out\n");
return -ETIME;
@@ -127,7 +175,10 @@ out_recv:
if (len < 0) {
rc = len;
dev_err(&chip->dev, "tpm_transmit: tpm_recv: error %d\n", rc);
- } else if (len < TPM_HEADER_SIZE || len != be32_to_cpu(header->length))
+ return rc;
+ }
+out_sync:
+ if (len < TPM_HEADER_SIZE || len != be32_to_cpu(header->length))
rc = -EFAULT;
return rc ? rc : len;
@@ -232,6 +283,7 @@ 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);
@@ -261,10 +313,13 @@ int tpm_is_tpm2(struct tpm_chip *chip)
{
int rc;
- chip = tpm_find_get_ops(chip);
if (!chip)
return -ENODEV;
+ rc = tpm_try_get_ops(chip);
+ if (rc)
+ return rc;
+
rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
tpm_put_ops(chip);
@@ -286,10 +341,13 @@ int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
{
int rc;
- chip = tpm_find_get_ops(chip);
if (!chip)
return -ENODEV;
+ rc = tpm_try_get_ops(chip);
+ if (rc)
+ return rc;
+
if (chip->flags & TPM_CHIP_FLAG_TPM2)
rc = tpm2_pcr_read(chip, pcr_idx, digest, NULL);
else
@@ -317,10 +375,13 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
int rc;
int i;
- chip = tpm_find_get_ops(chip);
if (!chip)
return -ENODEV;
+ rc = tpm_try_get_ops(chip);
+ if (rc)
+ return rc;
+
for (i = 0; i < chip->nr_allocated_banks; i++) {
if (digests[i].alg_id != chip->allocated_banks[i].alg_id) {
rc = -EINVAL;
@@ -342,31 +403,6 @@ out:
}
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;
@@ -394,6 +430,13 @@ int tpm_pm_suspend(struct device *dev)
if (!chip)
return -ENODEV;
+ rc = tpm_try_get_ops(chip);
+ if (rc) {
+ /* Can be safely set out of locks, as no action cannot race: */
+ chip->flags |= TPM_CHIP_FLAG_SUSPENDED;
+ goto out;
+ }
+
if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
goto suspended;
@@ -401,19 +444,19 @@ int tpm_pm_suspend(struct device *dev)
!pm_suspend_via_firmware())
goto suspended;
- rc = tpm_try_get_ops(chip);
- if (!rc) {
- if (chip->flags & TPM_CHIP_FLAG_TPM2)
- tpm2_shutdown(chip, TPM2_SU_STATE);
- else
- rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);
-
- tpm_put_ops(chip);
+ if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+ tpm2_end_auth_session(chip);
+ tpm2_shutdown(chip, TPM2_SU_STATE);
+ goto suspended;
}
+ rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);
+
suspended:
chip->flags |= TPM_CHIP_FLAG_SUSPENDED;
+ tpm_put_ops(chip);
+out:
if (rc)
dev_err(dev, "Ignoring error %d while suspending\n", rc);
return 0;
@@ -458,10 +501,13 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
if (!out || max > TPM_MAX_RNG_DATA)
return -EINVAL;
- chip = tpm_find_get_ops(chip);
if (!chip)
return -ENODEV;
+ rc = tpm_try_get_ops(chip);
+ if (rc)
+ return rc;
+
if (chip->flags & TPM_CHIP_FLAG_TPM2)
rc = tpm2_get_random(chip, out, max);
else
@@ -476,18 +522,15 @@ static int __init tpm_init(void)
{
int rc;
- tpm_class = class_create("tpm");
- if (IS_ERR(tpm_class)) {
+ rc = class_register(&tpm_class);
+ if (rc) {
pr_err("couldn't create tpm class\n");
- return PTR_ERR(tpm_class);
+ return rc;
}
- tpm_class->shutdown_pre = tpm_class_shutdown;
-
- tpmrm_class = class_create("tpmrm");
- if (IS_ERR(tpmrm_class)) {
+ rc = class_register(&tpmrm_class);
+ if (rc) {
pr_err("couldn't create tpmrm class\n");
- rc = PTR_ERR(tpmrm_class);
goto out_destroy_tpm_class;
}
@@ -508,9 +551,9 @@ static int __init tpm_init(void)
out_unreg_chrdev:
unregister_chrdev_region(tpm_devt, 2 * TPM_NUM_DEVICES);
out_destroy_tpmrm_class:
- class_destroy(tpmrm_class);
+ class_unregister(&tpmrm_class);
out_destroy_tpm_class:
- class_destroy(tpm_class);
+ class_unregister(&tpm_class);
return rc;
}
@@ -518,8 +561,8 @@ out_destroy_tpm_class:
static void __exit tpm_exit(void)
{
idr_destroy(&dev_nums_idr);
- class_destroy(tpm_class);
- class_destroy(tpmrm_class);
+ class_unregister(&tpm_class);
+ class_unregister(&tpmrm_class);
unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES);
tpm_dev_common_exit();
}
@@ -527,7 +570,7 @@ static void __exit tpm_exit(void)
subsys_initcall(tpm_init);
module_exit(tpm_exit);
-MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
+MODULE_AUTHOR("Leendert van Doorn <leendert@watson.ibm.com>");
MODULE_DESCRIPTION("TPM Driver");
MODULE_VERSION("2.0");
MODULE_LICENSE("GPL");
generated by cgit (git 2.34.1) at 2025-12-24 21:22:04 +0000