2 files changed, 87 insertions, 0 deletions
diff --git a/SecurityPkg/Library/PlatformPKProtectionLibVarPolicy/PlatformPKProtectionLibVarPolicy.c b/SecurityPkg/Library/PlatformPKProtectionLibVarPolicy/PlatformPKProtectionLibVarPolicy.c
new file mode 100644
index 0000000000..a264924224
--- /dev/null
+++ b/SecurityPkg/Library/PlatformPKProtectionLibVarPolicy/PlatformPKProtectionLibVarPolicy.c
@@ -0,0 +1,51 @@
+/** @file
+  Provides an abstracted interface for configuring PK related variable protection.
+
+  Copyright (c) Microsoft Corporation.
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#include <Uefi.h>
+#include <Protocol/VariablePolicy.h>
+
+#include <Library/DebugLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+
+/**
+  Disable any applicable protection against variable 'PK'. The implementation
+  of this interface is platform specific, depending on the protection techniques
+  used per platform.
+
+  Note: It is the platform's responsibility to conduct cautious operation after
+        disabling this protection.
+
+  @retval     EFI_SUCCESS             State has been successfully updated.
+  @retval     Others                  Error returned from implementation specific
+                                      underying APIs.
+
+**/
+EFI_STATUS
+EFIAPI
+DisablePKProtection (
+  VOID
+  )
+{
+  EFI_STATUS                      Status;
+  EDKII_VARIABLE_POLICY_PROTOCOL  *VariablePolicy;
+
+  DEBUG ((DEBUG_INFO, "%a() Entry...\n", __FUNCTION__));
+
+  // IMPORTANT NOTE: This operation is sticky and leaves variable protections disabled.
+  //                  The system *MUST* be reset after performing this operation.
+  Status = gBS->LocateProtocol (&gEdkiiVariablePolicyProtocolGuid, NULL, (VOID **)&VariablePolicy);
+  if (!EFI_ERROR (Status)) {
+    Status = VariablePolicy->DisableVariablePolicy ();
+    // EFI_ALREADY_STARTED means that everything is currently disabled.
+    // This should be considered SUCCESS.
+    if (Status == EFI_ALREADY_STARTED) {
+      Status = EFI_SUCCESS;
+    }
+  }
+
+  return Status;
+}
diff --git a/SecurityPkg/Library/PlatformPKProtectionLibVarPolicy/PlatformPKProtectionLibVarPolicy.inf b/SecurityPkg/Library/PlatformPKProtectionLibVarPolicy/PlatformPKProtectionLibVarPolicy.inf
new file mode 100644
index 0000000000..df42ce06c0
--- /dev/null
+++ b/SecurityPkg/Library/PlatformPKProtectionLibVarPolicy/PlatformPKProtectionLibVarPolicy.inf
@@ -0,0 +1,36 @@
+## @file
+#  Provides an abstracted interface for configuring PK related variable protection.
+#
+#  Copyright (c) Microsoft Corporation.
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = PlatformPKProtectionLibVarPolicy
+  FILE_GUID                      = AE0C5992-526C-4518-93BA-3C2611B801E0
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = PlatformPKProtectionLib|DXE_DRIVER DXE_RUNTIME_DRIVER UEFI_APPLICATION
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64 AARCH64
+#
+
+[Sources]
+  PlatformPKProtectionLibVarPolicy.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  SecurityPkg/SecurityPkg.dec
+
+[LibraryClasses]
+  DebugLib
+  UefiBootServicesTableLib
+
+[Protocols]
+  gEdkiiVariablePolicyProtocolGuid