[PATCH v5 19/21] tpm1: reimplement SAVESTATE using tpm_buf

From: Tomas Winkler
Date: Fri Sep 28 2018 - 18:35:34 EST


In tpm1_pm_suspend() function reimplement,
TPM_ORD_SAVESTATE comamnd using tpm_buf.

Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
---
V3: New in the series.
V4-V5: Resend

drivers/char/tpm/tpm1-cmd.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
index 05b772477bac..d418a27a75e0 100644
--- a/drivers/char/tpm/tpm1-cmd.c
+++ b/drivers/char/tpm/tpm1-cmd.c
@@ -718,12 +718,6 @@ int tpm1_auto_startup(struct tpm_chip *chip)
}

#define TPM_ORD_SAVESTATE 152
-#define SAVESTATE_RESULT_SIZE 10
-static const struct tpm_input_header savestate_header = {
- .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
- .length = cpu_to_be32(10),
- .ordinal = cpu_to_be32(TPM_ORD_SAVESTATE)
-};

/**
* tpm1_pm_suspend() - pm suspend handler
@@ -739,18 +733,22 @@ static const struct tpm_input_header savestate_header = {
int tpm1_pm_suspend(struct tpm_chip *chip, int tpm_suspend_pcr)
{
u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
- struct tpm_cmd_t cmd;
- int rc, try;
+ struct tpm_buf buf;
+ unsigned int try;
+ int rc;
+

/* for buggy tpm, flush pcrs with extend to selected dummy */
if (tpm_suspend_pcr)
rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
"extending dummy pcr before suspend");

+ rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
+ if (rc)
+ return rc;
/* now do the actual savestate */
for (try = 0; try < TPM_RETRY; try++) {
- cmd.header.in = savestate_header;
- rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
0, 0, NULL);

/*
@@ -766,6 +764,8 @@ int tpm1_pm_suspend(struct tpm_chip *chip, int tpm_suspend_pcr)
if (rc != TPM_WARN_RETRY)
break;
tpm_msleep(TPM_TIMEOUT_RETRY);
+
+ tpm_buf_reset(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
}

if (rc)
@@ -775,6 +775,8 @@ int tpm1_pm_suspend(struct tpm_chip *chip, int tpm_suspend_pcr)
dev_warn(&chip->dev, "TPM savestate took %dms\n",
try * TPM_TIMEOUT_RETRY);

+ tpm_buf_destroy(&buf);
+
return rc;
}

--
2.14.4