[PATCH v4 7/8] SecurityPkg/Tcg2: handle PRE HASH and LOG ONLY

["Qi Zhang" <qi1.zhang@intel.com>]

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2376

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Qi Zhang <qi1.zhang@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Signed-off-by: Qi Zhang <qi1.zhang@intel.com>
---
 SecurityPkg/Include/Ppi/Tcg.h     |  5 +++++
 SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c | 12 +++++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/SecurityPkg/Include/Ppi/Tcg.h b/SecurityPkg/Include/Ppi/Tcg.h
index 0e943f2465..22f47f9817 100644
--- a/SecurityPkg/Include/Ppi/Tcg.h
+++ b/SecurityPkg/Include/Ppi/Tcg.h
@@ -18,6 +18,11 @@ typedef struct _EDKII_TCG_PPI EDKII_TCG_PPI;
 //
 #define EDKII_TCG_PRE_HASH  0x0000000000000001
 
+//
+// This bit is shall be set when HashData is the pre-hash digest and log only.
+//
+#define EDKII_TCG_PRE_HASH_LOG_ONLY  0x0000000000000002
+
 /**
   Tpm measure and log data, and extend the measurement result into a specific PCR.
 
diff --git a/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c b/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c
index 246968bb7f..0e770f4485 100644
--- a/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c
+++ b/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c
@@ -453,13 +453,15 @@ HashLogExtendEvent (
     return EFI_DEVICE_ERROR;
   }
 
-  if(Flags & EDKII_TCG_PRE_HASH) {
+  if ((Flags & EDKII_TCG_PRE_HASH) != 0 || (Flags & EDKII_TCG_PRE_HASH_LOG_ONLY) != 0) {
     ZeroMem (&DigestList, sizeof(DigestList));
     CopyMem (&DigestList, HashData, sizeof(DigestList));
-    Status = Tpm2PcrExtend (
-             0,
-             &DigestList
-             );
+    if ((Flags & EDKII_TCG_PRE_HASH) !=0 ) {
+      Status = Tpm2PcrExtend (
+               NewEventHdr->PCRIndex,
+               &DigestList
+               );
+    }
   } else {
     Status = HashAndExtend (
                NewEventHdr->PCRIndex,
-- 
2.26.2.windows.1