1 files changed, 80 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/SecurityPkg/Library/Tpm2CommandLib/Tpm2Context.c b/src/VBox/Devices/EFI/Firmware/SecurityPkg/Library/Tpm2CommandLib/Tpm2Context.c
new file mode 100644
index 00000000..101f51eb
--- /dev/null
+++ b/src/VBox/Devices/EFI/Firmware/SecurityPkg/Library/Tpm2CommandLib/Tpm2Context.c
@@ -0,0 +1,80 @@
+/** @file
+  Implement TPM2 Context related command.
+
+Copyright (c) 2014 - 2018, Intel Corporation. All rights reserved. <BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <IndustryStandard/UefiTcgPlatform.h>
+#include <Library/Tpm2CommandLib.h>
+#include <Library/Tpm2DeviceLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+
+#pragma pack(1)
+
+typedef struct {
+  TPM2_COMMAND_HEADER       Header;
+  TPMI_DH_CONTEXT           FlushHandle;
+} TPM2_FLUSH_CONTEXT_COMMAND;
+
+typedef struct {
+  TPM2_RESPONSE_HEADER      Header;
+} TPM2_FLUSH_CONTEXT_RESPONSE;
+
+#pragma pack()
+
+/**
+  This command causes all context associated with a loaded object or session to be removed from TPM memory.
+
+  @param[in]  FlushHandle        The handle of the item to flush.
+
+  @retval EFI_SUCCESS            Operation completed successfully.
+  @retval EFI_DEVICE_ERROR       The command was unsuccessful.
+**/
+EFI_STATUS
+EFIAPI
+Tpm2FlushContext (
+  IN      TPMI_DH_CONTEXT           FlushHandle
+  )
+{
+  EFI_STATUS                        Status;
+  TPM2_FLUSH_CONTEXT_COMMAND        SendBuffer;
+  TPM2_FLUSH_CONTEXT_RESPONSE       RecvBuffer;
+  UINT32                            SendBufferSize;
+  UINT32                            RecvBufferSize;
+
+  //
+  // Construct command
+  //
+  SendBuffer.Header.tag = SwapBytes16(TPM_ST_NO_SESSIONS);
+  SendBuffer.Header.commandCode = SwapBytes32(TPM_CC_FlushContext);
+
+  SendBuffer.FlushHandle = SwapBytes32 (FlushHandle);
+
+  SendBufferSize = (UINT32) sizeof (SendBuffer);
+  SendBuffer.Header.paramSize = SwapBytes32 (SendBufferSize);
+
+  //
+  // send Tpm command
+  //
+  RecvBufferSize = sizeof (RecvBuffer);
+  Status = Tpm2SubmitCommand (SendBufferSize, (UINT8 *)&SendBuffer, &RecvBufferSize, (UINT8 *)&RecvBuffer);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  if (RecvBufferSize < sizeof (TPM2_RESPONSE_HEADER)) {
+    DEBUG ((EFI_D_ERROR, "Tpm2FlushContext - RecvBufferSize Error - %x\n", RecvBufferSize));
+    return EFI_DEVICE_ERROR;
+  }
+  if (SwapBytes32(RecvBuffer.Header.responseCode) != TPM_RC_SUCCESS) {
+    DEBUG ((EFI_D_ERROR, "Tpm2FlushContext - responseCode - %x\n", SwapBytes32(RecvBuffer.Header.responseCode)));
+    return EFI_DEVICE_ERROR;
+  }
+
+  return EFI_SUCCESS;
+}
+