From 1b0d659e6dc987d27f63da94c9fe3f26ba171d15 Mon Sep 17 00:00:00 2001
From: "Zhang, Qi" <qi1.zhang@intel.com>
Date: Tue, 28 Jul 2020 16:20:39 +0800
Subject: [PATCH] SecurityPkg/Tpm2CommandLib: add a new function

 Tpm2GetCapabilityIsCommandImplemented

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2793

check if the commad is supported by comparing the command code with
command index.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Chao Zhang <chao.b.zhang@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Signed-off-by: Qi Zhang <qi1.zhang@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
---
 SecurityPkg/Include/Library/Tpm2CommandLib.h  | 16 ++++++++
 .../Library/Tpm2CommandLib/Tpm2Capability.c   | 40 +++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/SecurityPkg/Include/Library/Tpm2CommandLib.h b/SecurityPkg/Include/Library/Tpm2CommandLib.h
index ce381e786b..ee8eb62295 100644
--- a/SecurityPkg/Include/Library/Tpm2CommandLib.h
+++ b/SecurityPkg/Include/Library/Tpm2CommandLib.h
@@ -790,6 +790,22 @@ Tpm2GetCapabilityAlgorithmSet (
   OUT     UINT32      *AlgorithmSet
   );
 
+/**
+  This function will query if the command is supported.
+
+  @param[In]  Command         TPM_CC command starts from TPM_CC_FIRST.
+  @param[out] IsCmdImpl       The command is supported or not.
+
+  @retval EFI_SUCCESS            Operation completed successfully.
+  @retval EFI_DEVICE_ERROR       The command was unsuccessful.
+**/
+EFI_STATUS
+EFIAPI
+Tpm2GetCapabilityIsCommandImplemented (
+  IN      TPM_CC      Command,
+  OUT     BOOLEAN     *IsCmdImpl
+  );
+
 /**
   This command is used to check to see if specific combinations of algorithm parameters are supported.
 
diff --git a/SecurityPkg/Library/Tpm2CommandLib/Tpm2Capability.c b/SecurityPkg/Library/Tpm2CommandLib/Tpm2Capability.c
index 85b11c7715..17c0c3a151 100644
--- a/SecurityPkg/Library/Tpm2CommandLib/Tpm2Capability.c
+++ b/SecurityPkg/Library/Tpm2CommandLib/Tpm2Capability.c
@@ -39,6 +39,8 @@ typedef struct {
 
 #pragma pack()
 
+#define TPMA_CC_COMMANDINDEX_MASK  0x2000FFFF
+
 /**
   This command returns various information regarding the TPM and its current state.
 
@@ -628,6 +630,44 @@ Tpm2GetCapabilityAlgorithmSet (
   return EFI_SUCCESS;
 }
 
+/**
+  This function will query if the command is supported.
+
+  @param[In]  Command         TPM_CC command starts from TPM_CC_FIRST.
+  @param[out] IsCmdImpl       The command is supported or not.
+
+  @retval EFI_SUCCESS            Operation completed successfully.
+  @retval EFI_DEVICE_ERROR       The command was unsuccessful.
+**/
+EFI_STATUS
+EFIAPI
+Tpm2GetCapabilityIsCommandImplemented (
+  IN      TPM_CC      Command,
+  OUT     BOOLEAN     *IsCmdImpl
+  )
+{
+  TPMS_CAPABILITY_DATA    TpmCap;
+  TPMI_YES_NO             MoreData;
+  EFI_STATUS              Status;
+  UINT32                  Attribute;
+
+  Status = Tpm2GetCapability (
+             TPM_CAP_COMMANDS,
+             Command,
+             1,
+             &MoreData,
+             &TpmCap
+             );
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  CopyMem (&Attribute, &TpmCap.data.command.commandAttributes[0], sizeof (UINT32));
+  *IsCmdImpl = (Command == (SwapBytes32(Attribute) & TPMA_CC_COMMANDINDEX_MASK));
+
+  return EFI_SUCCESS;
+}
+
 /**
   This command is used to check to see if specific combinations of algorithm parameters are supported.