2 files changed, 24 insertions, 0 deletions
diff --git a/src/security/tpm/tss.h b/src/security/tpm/tss.h
index 5237387a74..57f3b24847 100644
--- a/src/security/tpm/tss.h
+++ b/src/security/tpm/tss.h
@@ -197,4 +197,9 @@ uint32_t tlcl_extend(int pcr_num, const uint8_t *in_digest,
  */
 uint32_t tlcl_disable_platform_hierarchy(void);
 
+/**
+ * Get the permission bits for the NVRAM space with |index|.
+ */
+uint32_t tlcl_get_permissions(uint32_t index, uint32_t *permissions);
+
 #endif /* TSS_H_ */
diff --git a/src/security/tpm/tss/tcg-1.2/tss.c b/src/security/tpm/tss/tcg-1.2/tss.c
index 9bc72d2733..ea3f94d5f8 100644
--- a/src/security/tpm/tss/tcg-1.2/tss.c
+++ b/src/security/tpm/tss/tcg-1.2/tss.c
@@ -359,3 +359,22 @@ uint32_t tlcl_extend(int pcr_num, const uint8_t *in_digest,
 		       kPcrDigestLength);
 	return result;
 }
+
+uint32_t tlcl_get_permissions(uint32_t index, uint32_t *permissions)
+{
+	struct s_tpm_getpermissions_cmd cmd;
+	uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE];
+	uint8_t *nvdata;
+	uint32_t result;
+	uint32_t size;
+
+	memcpy(&cmd, &tpm_getpermissions_cmd, sizeof(cmd));
+	to_tpm_uint32(cmd.buffer + tpm_getpermissions_cmd.index, index);
+	result = tlcl_send_receive(cmd.buffer, response, sizeof(response));
+	if (result != TPM_SUCCESS)
+		return result;
+
+	nvdata = response + kTpmResponseHeaderLength + sizeof(size);
+	from_tpm_uint32(nvdata + kNvDataPublicPermissionsOffset, permissions);
+	return result;
+}