[coreboot-gerrit] Change in coreboot[master]: security/tpm: Add TPM_PCRRead tss function

[Philipp Deppenwiese (Code Review)]

Philipp Deppenwiese has uploaded this change for review. ( https://review.coreboot.org/22831

Change subject: security/tpm: Add TPM_PCRRead tss function
......................................................................

security/tpm: Add TPM_PCRRead tss function

Change-Id: Ic85517a8a69f352a02d20a67fbba3d910ef03a1c
Signed-off-by: Philipp Deppenwiese 
---
M src/security/tpm/tss.h
M src/security/tpm/tss/tcg-1.2/tss.c
M src/security/tpm/tss/tcg-2.0/tss.c
3 files changed, 27 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/31/22831/1

diff --git a/src/security/tpm/tss.h b/src/security/tpm/tss.h
index 3cc50ef..612df0f 100644
--- a/src/security/tpm/tss.h
+++ b/src/security/tpm/tss.h
@@ -151,6 +151,11 @@
    	     uint8_t *out_digest);

/**
+ * Read current PCR digest
+ */
+uint32_t tlcl_pcr_read(int pcr_num, uint8_t *out_digest);
+
+/**
  * Get the entire set of permanent flags.
  */
 uint32_t tlcl_get_permanent_flags(TPM_PERMANENT_FLAGS *pflags);
diff --git a/src/security/tpm/tss/tcg-1.2/tss.c b/src/security/tpm/tss/tcg-1.2/tss.c
index b74abd0..2bb2269 100644
--- a/src/security/tpm/tss/tcg-1.2/tss.c
+++ b/src/security/tpm/tss/tcg-1.2/tss.c
@@ -411,3 +411,20 @@

return result;
 }
+
+uint32_t tlcl_pcr_read(int pcr_num, uint8_t *out_digest)
+{
+	struct s_tpm_pcr_read_cmd cmd;
+	uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE];
+	uint32_t result;
+
+	memcpy(&cmd, &tpm_pcr_read_cmd, sizeof(cmd));
+	to_tpm_uint32(cmd.buffer + tpm_pcr_read_cmd.pcrNum, pcr_num);
+
+	result = tlcl_send_receive(cmd.buffer, response, sizeof(response));
+	if (result == TPM_SUCCESS)
+		memcpy(out_digest, response + kTpmResponseHeaderLength,
+				kPcrDigestLength);
+
+	return result;
+}
diff --git a/src/security/tpm/tss/tcg-2.0/tss.c b/src/security/tpm/tss/tcg-2.0/tss.c
index 0dbf8c8..0bee09b 100644
--- a/src/security/tpm/tss/tcg-2.0/tss.c
+++ b/src/security/tpm/tss/tcg-2.0/tss.c
@@ -416,3 +416,8 @@
 {
    return TPM_SUCCESS;
 }
+
+uint32_t tlcl_pcr_read(int pcr_num, uint8_t *out_digest)
+{
+	return TPM_SUCCESS;
+}