SecurityPkg: Create SecureBootVariableLib.

This commits add library, which consist helper functions related
to creation/removal Secure Boot variables. Some of the functions
was moved from SecureBootConfigImpl.c file.

Signed-off-by: Grzegorz Bernacki <gjb@semihalf.com>
Reviewed-by: Sunny Wang <sunny.wang@arm.com>
Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>

SecurityPkg/Include/Library/SecureBootVariableLib.h

@@ -0,0 +1,153 @@
+/** @file
+  Provides a helper functions for creating variable authenticated
+  payloads, signature lists related to secure boot keys.
+
+Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved.<BR>
+(C) Copyright 2018 Hewlett Packard Enterprise Development LP<BR>
+Copyright (c) 2021, ARM Ltd. All rights reserved.<BR>
+Copyright (c) 2021, Semihalf All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef SECURE_BOOT_VARIABLE_LIB_H_
+#define SECURE_BOOT_VARIABLE_LIB_H_
+
+/**
+  Set the platform secure boot mode into "Custom" or "Standard" mode.
+
+  @param[in]   SecureBootMode        New secure boot mode: STANDARD_SECURE_BOOT_MODE or
+                                     CUSTOM_SECURE_BOOT_MODE.
+
+  @return EFI_SUCCESS                The platform has switched to the special mode successfully.
+  @return other                      Fail to operate the secure boot mode.
+
+--*/
+EFI_STATUS
+SetSecureBootMode (
+  IN  UINT8  SecureBootMode
+);
+
+/**
+  Fetches the value of SetupMode variable.
+
+  @param[out] SetupMode             Pointer to UINT8 for SetupMode output
+
+  @retval other                     Error codes from GetVariable.
+--*/
+EFI_STATUS
+EFIAPI
+GetSetupMode (
+  OUT UINT8 *SetupMode
+);
+
+/**
+  Create a EFI Signature List with data fetched from section specified as a argument.
+  Found keys are verified using RsaGetPublicKeyFromX509().
+
+  @param[in]        KeyFileGuid    A pointer to to the FFS filename GUID
+  @param[out]       SigListsSize   A pointer to size of signature list
+  @param[out]       SigListsOut    a pointer to a callee-allocated buffer with signature lists
+
+  @retval EFI_SUCCESS              Create time based payload successfully.
+  @retval EFI_NOT_FOUND            Section with key has not been found.
+  @retval EFI_INVALID_PARAMETER    Embedded key has a wrong format.
+  @retval Others                   Unexpected error happens.
+
+--*/
+EFI_STATUS
+SecureBootFetchData (
+    IN  EFI_GUID           *KeyFileGuid,
+    OUT UINTN              *SigListsSize,
+    OUT EFI_SIGNATURE_LIST **SigListOut
+);
+
+/**
+  Create a time based data payload by concatenating the EFI_VARIABLE_AUTHENTICATION_2
+  descriptor with the input data. NO authentication is required in this function.
+
+  @param[in, out]   DataSize       On input, the size of Data buffer in bytes.
+                                   On output, the size of data returned in Data
+                                   buffer in bytes.
+  @param[in, out]   Data           On input, Pointer to data buffer to be wrapped or
+                                   pointer to NULL to wrap an empty payload.
+                                   On output, Pointer to the new payload date buffer allocated from pool,
+                                   it's caller's responsibility to free the memory when finish using it.
+
+  @retval EFI_SUCCESS              Create time based payload successfully.
+  @retval EFI_OUT_OF_RESOURCES     There are not enough memory resources to create time based payload.
+  @retval EFI_INVALID_PARAMETER    The parameter is invalid.
+  @retval Others                   Unexpected error happens.
+
+--*/
+EFI_STATUS
+CreateTimeBasedPayload (
+  IN OUT UINTN            *DataSize,
+  IN OUT UINT8            **Data
+);
+
+/**
+  Clears the content of the 'db' variable.
+
+  @retval EFI_OUT_OF_RESOURCES      If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
+                                    while VendorGuid is NULL.
+  @retval other                     Errors from GetVariable2(), GetTime() and SetVariable()
+--*/
+EFI_STATUS
+EFIAPI
+DeleteDb (
+  VOID
+);
+
+/**
+  Clears the content of the 'dbx' variable.
+
+  @retval EFI_OUT_OF_RESOURCES      If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
+                                    while VendorGuid is NULL.
+  @retval other                     Errors from GetVariable2(), GetTime() and SetVariable()
+--*/
+EFI_STATUS
+EFIAPI
+DeleteDbx (
+  VOID
+);
+
+/**
+  Clears the content of the 'dbt' variable.
+
+  @retval EFI_OUT_OF_RESOURCES      If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
+                                    while VendorGuid is NULL.
+  @retval other                     Errors from GetVariable2(), GetTime() and SetVariable()
+--*/
+EFI_STATUS
+EFIAPI
+DeleteDbt (
+  VOID
+);
+
+/**
+  Clears the content of the 'KEK' variable.
+
+  @retval EFI_OUT_OF_RESOURCES      If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
+                                    while VendorGuid is NULL.
+  @retval other                     Errors from GetVariable2(), GetTime() and SetVariable()
+--*/
+EFI_STATUS
+EFIAPI
+DeleteKEK (
+  VOID
+);
+
+/**
+  Clears the content of the 'PK' variable.
+
+  @retval EFI_OUT_OF_RESOURCES      If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
+                                    while VendorGuid is NULL.
+  @retval other                     Errors from GetVariable2(), GetTime() and SetVariable()
+--*/
+EFI_STATUS
+EFIAPI
+DeletePlatformKey (
+  VOID
+);
+#endif