[PATCH v7 01/11] SecurityPkg: Create SecureBootVariableLib.


Grzegorz Bernacki
 

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/SecurityPkg.dec | 4 +
SecurityPkg/SecurityPkg.dsc | 1 +
SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.inf | 80 +++
SecurityPkg/Include/Library/SecureBootVariableLib.h | 153 ++++++
SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.c | 510 ++++++++++++++++++++
SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.uni | 17 +
6 files changed, 765 insertions(+)
create mode 100644 SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.inf
create mode 100644 SecurityPkg/Include/Library/SecureBootVariableLib.h
create mode 100644 SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.c
create mode 100644 SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.uni

diff --git a/SecurityPkg/SecurityPkg.dec b/SecurityPkg/SecurityPkg.dec
index 4001650fa2..8f3710e59f 100644
--- a/SecurityPkg/SecurityPkg.dec
+++ b/SecurityPkg/SecurityPkg.dec
@@ -87,6 +87,10 @@
## @libraryclass Provides interfaces about firmware TPM measurement.
#
TcgEventLogRecordLib|Include/Library/TcgEventLogRecordLib.h
+
+ ## @libraryclass Provides helper functions related to creation/removal Secure Boot variables.
+ #
+ SecureBootVariableLib|Include/Library/SecureBootVariableLib.h
[Guids]
## Security package token space guid.
# Include/Guid/SecurityPkgTokenSpace.h
diff --git a/SecurityPkg/SecurityPkg.dsc b/SecurityPkg/SecurityPkg.dsc
index bd4b810bce..854f250625 100644
--- a/SecurityPkg/SecurityPkg.dsc
+++ b/SecurityPkg/SecurityPkg.dsc
@@ -70,6 +70,7 @@
RpmcLib|SecurityPkg/Library/RpmcLibNull/RpmcLibNull.inf
TcgEventLogRecordLib|SecurityPkg/Library/TcgEventLogRecordLib/TcgEventLogRecordLib.inf
MmUnblockMemoryLib|MdePkg/Library/MmUnblockMemoryLib/MmUnblockMemoryLibNull.inf
+ SecureBootVariableLib|SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.inf

[LibraryClasses.ARM]
#
diff --git a/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.inf b/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.inf
new file mode 100644
index 0000000000..b32814736d
--- /dev/null
+++ b/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.inf
@@ -0,0 +1,80 @@
+## @file
+# Provides helper function for initialization of Secure Boot
+# keys and databases.
+#
+# Copyright (c) 2021, ARM Ltd. All rights reserved.<BR>
+# Copyright (c) 2021, Semihalf All rights reserved.<BR>
+#
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+ INF_VERSION = 0x00010005
+ BASE_NAME = SecureBootVariableLib
+ MODULE_UNI_FILE = SecureBootVariableLib.uni
+ FILE_GUID = D4FFF5CA-6D8E-4DBD-8A4B-7C7CEBD97F6F
+ MODULE_TYPE = DXE_DRIVER
+ VERSION_STRING = 1.0
+ LIBRARY_CLASS = SecureBootVariableLib|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]
+ SecureBootVariableLib.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+ MdeModulePkg/MdeModulePkg.dec
+ SecurityPkg/SecurityPkg.dec
+ CryptoPkg/CryptoPkg.dec
+
+[LibraryClasses]
+ BaseLib
+ BaseMemoryLib
+ DebugLib
+ MemoryAllocationLib
+ BaseCryptLib
+ DxeServicesLib
+
+[Guids]
+ ## CONSUMES ## Variable:L"SetupMode"
+ ## PRODUCES ## Variable:L"SetupMode"
+ ## CONSUMES ## Variable:L"SecureBoot"
+ ## PRODUCES ## Variable:L"SecureBoot"
+ ## PRODUCES ## Variable:L"PK"
+ ## PRODUCES ## Variable:L"KEK"
+ ## CONSUMES ## Variable:L"PKDefault"
+ ## CONSUMES ## Variable:L"KEKDefault"
+ ## CONSUMES ## Variable:L"dbDefault"
+ ## CONSUMES ## Variable:L"dbxDefault"
+ ## CONSUMES ## Variable:L"dbtDefault"
+ gEfiGlobalVariableGuid
+
+ ## SOMETIMES_CONSUMES ## Variable:L"DB"
+ ## SOMETIMES_CONSUMES ## Variable:L"DBX"
+ ## SOMETIMES_CONSUMES ## Variable:L"DBT"
+ gEfiImageSecurityDatabaseGuid
+
+ ## CONSUMES ## Variable:L"SecureBootEnable"
+ ## PRODUCES ## Variable:L"SecureBootEnable"
+ gEfiSecureBootEnableDisableGuid
+
+ ## CONSUMES ## Variable:L"CustomMode"
+ ## PRODUCES ## Variable:L"CustomMode"
+ gEfiCustomModeEnableGuid
+
+ gEfiCertTypeRsa2048Sha256Guid ## CONSUMES
+ gEfiCertX509Guid ## CONSUMES
+ gEfiCertPkcs7Guid ## CONSUMES
+
+ gDefaultPKFileGuid
+ gDefaultKEKFileGuid
+ gDefaultdbFileGuid
+ gDefaultdbxFileGuid
+ gDefaultdbtFileGuid
+
diff --git a/SecurityPkg/Include/Library/SecureBootVariableLib.h b/SecurityPkg/Include/Library/SecureBootVariableLib.h
new file mode 100644
index 0000000000..6e6d624071
--- /dev/null
+++ b/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
diff --git a/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.c b/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.c
new file mode 100644
index 0000000000..ce99f6c808
--- /dev/null
+++ b/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.c
@@ -0,0 +1,510 @@
+/** @file
+ This library provides helper functions to set/clear Secure Boot
+ keys and databases.
+
+ 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
+**/
+#include <Guid/GlobalVariable.h>
+#include <Guid/AuthenticatedVariableFormat.h>
+#include <Guid/ImageAuthentication.h>
+#include <Library/BaseCryptLib.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/UefiLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+#include <Library/SecureBootVariableLib.h>
+#include "Library/DxeServicesLib.h"
+
+/** Creates EFI Signature List structure.
+
+ @param[in] Data A pointer to signature data.
+ @param[in] Size Size of signature data.
+ @param[out] SigList Created Signature List.
+
+ @retval EFI_SUCCESS Signature List was created successfully.
+ @retval EFI_OUT_OF_RESOURCES Failed to allocate memory.
+--*/
+STATIC
+EFI_STATUS
+CreateSigList (
+ IN VOID *Data,
+ IN UINTN Size,
+ OUT EFI_SIGNATURE_LIST **SigList
+ )
+{
+ UINTN SigListSize;
+ EFI_SIGNATURE_LIST *TmpSigList;
+ EFI_SIGNATURE_DATA *SigData;
+
+ //
+ // Allocate data for Signature Database
+ //
+ SigListSize = sizeof (EFI_SIGNATURE_LIST) + sizeof (EFI_SIGNATURE_DATA) - 1 + Size;
+ TmpSigList = (EFI_SIGNATURE_LIST *) AllocateZeroPool (SigListSize);
+ if (TmpSigList == NULL) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ //
+ // Only gEfiCertX509Guid type is supported
+ //
+ TmpSigList->SignatureListSize = (UINT32)SigListSize;
+ TmpSigList->SignatureSize = (UINT32) (sizeof (EFI_SIGNATURE_DATA) - 1 + Size);
+ TmpSigList->SignatureHeaderSize = 0;
+ CopyGuid (&TmpSigList->SignatureType, &gEfiCertX509Guid);
+
+ //
+ // Copy key data
+ //
+ SigData = (EFI_SIGNATURE_DATA *) (TmpSigList + 1);
+ CopyGuid (&SigData->SignatureOwner, &gEfiGlobalVariableGuid);
+ CopyMem (&SigData->SignatureData[0], Data, Size);
+
+ *SigList = TmpSigList;
+
+ return EFI_SUCCESS;
+}
+
+/** Adds new signature list to signature database.
+
+ @param[in] SigLists A pointer to signature database.
+ @param[in] SigListAppend A signature list to be added.
+ @param[out] *SigListOut Created signature database.
+ @param[in, out] SigListsSize A size of created signature database.
+
+ @retval EFI_SUCCESS Signature List was added successfully.
+ @retval EFI_OUT_OF_RESOURCES Failed to allocate memory.
+--*/
+STATIC
+EFI_STATUS
+ConcatenateSigList (
+ IN EFI_SIGNATURE_LIST *SigLists,
+ IN EFI_SIGNATURE_LIST *SigListAppend,
+ OUT EFI_SIGNATURE_LIST **SigListOut,
+ IN OUT UINTN *SigListsSize
+)
+{
+ EFI_SIGNATURE_LIST *TmpSigList;
+ UINT8 *Offset;
+ UINTN NewSigListsSize;
+
+ NewSigListsSize = *SigListsSize + SigListAppend->SignatureListSize;
+
+ TmpSigList = (EFI_SIGNATURE_LIST *) AllocateZeroPool (NewSigListsSize);
+ if (TmpSigList == NULL) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ CopyMem (TmpSigList, SigLists, *SigListsSize);
+
+ Offset = (UINT8 *)TmpSigList;
+ Offset += *SigListsSize;
+ CopyMem ((VOID *)Offset, SigListAppend, SigListAppend->SignatureListSize);
+
+ *SigListsSize = NewSigListsSize;
+ *SigListOut = TmpSigList;
+ return EFI_SUCCESS;
+}
+
+/**
+ 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] SigListOut 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
+)
+{
+ EFI_SIGNATURE_LIST *EfiSig;
+ EFI_SIGNATURE_LIST *TmpEfiSig;
+ EFI_SIGNATURE_LIST *TmpEfiSig2;
+ EFI_STATUS Status;
+ VOID *Buffer;
+ VOID *RsaPubKey;
+ UINTN Size;
+ UINTN KeyIndex;
+
+
+ KeyIndex = 0;
+ EfiSig = NULL;
+ *SigListsSize = 0;
+ while (1) {
+ Status = GetSectionFromAnyFv (
+ KeyFileGuid,
+ EFI_SECTION_RAW,
+ KeyIndex,
+ &Buffer,
+ &Size
+ );
+
+ if (Status == EFI_SUCCESS) {
+ RsaPubKey = NULL;
+ if (RsaGetPublicKeyFromX509 (Buffer, Size, &RsaPubKey) == FALSE) {
+ DEBUG ((DEBUG_ERROR, "%a: Invalid key format: %d\n", __FUNCTION__, KeyIndex));
+ if (EfiSig != NULL) {
+ FreePool(EfiSig);
+ }
+ FreePool(Buffer);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Status = CreateSigList (Buffer, Size, &TmpEfiSig);
+
+ //
+ // Concatenate lists if more than one section found
+ //
+ if (KeyIndex == 0) {
+ EfiSig = TmpEfiSig;
+ *SigListsSize = TmpEfiSig->SignatureListSize;
+ } else {
+ ConcatenateSigList (EfiSig, TmpEfiSig, &TmpEfiSig2, SigListsSize);
+ FreePool (EfiSig);
+ FreePool (TmpEfiSig);
+ EfiSig = TmpEfiSig2;
+ }
+
+ KeyIndex++;
+ FreePool (Buffer);
+ } if (Status == EFI_NOT_FOUND) {
+ break;
+ }
+ };
+
+ if (KeyIndex == 0) {
+ return EFI_NOT_FOUND;
+ }
+
+ *SigListOut = EfiSig;
+
+ return EFI_SUCCESS;
+}
+
+/**
+ 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
+ )
+{
+ EFI_STATUS Status;
+ UINT8 *NewData;
+ UINT8 *Payload;
+ UINTN PayloadSize;
+ EFI_VARIABLE_AUTHENTICATION_2 *DescriptorData;
+ UINTN DescriptorSize;
+ EFI_TIME Time;
+
+ if (Data == NULL || DataSize == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // In Setup mode or Custom mode, the variable does not need to be signed but the
+ // parameters to the SetVariable() call still need to be prepared as authenticated
+ // variable. So we create EFI_VARIABLE_AUTHENTICATED_2 descriptor without certificate
+ // data in it.
+ //
+ Payload = *Data;
+ PayloadSize = *DataSize;
+
+ DescriptorSize = OFFSET_OF (EFI_VARIABLE_AUTHENTICATION_2, AuthInfo) + OFFSET_OF (WIN_CERTIFICATE_UEFI_GUID, CertData);
+ NewData = (UINT8*) AllocateZeroPool (DescriptorSize + PayloadSize);
+ if (NewData == NULL) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ if ((Payload != NULL) && (PayloadSize != 0)) {
+ CopyMem (NewData + DescriptorSize, Payload, PayloadSize);
+ }
+
+ DescriptorData = (EFI_VARIABLE_AUTHENTICATION_2 *) (NewData);
+
+ ZeroMem (&Time, sizeof (EFI_TIME));
+ Status = gRT->GetTime (&Time, NULL);
+ if (EFI_ERROR (Status)) {
+ FreePool(NewData);
+ return Status;
+ }
+ Time.Pad1 = 0;
+ Time.Nanosecond = 0;
+ Time.TimeZone = 0;
+ Time.Daylight = 0;
+ Time.Pad2 = 0;
+ CopyMem (&DescriptorData->TimeStamp, &Time, sizeof (EFI_TIME));
+
+ DescriptorData->AuthInfo.Hdr.dwLength = OFFSET_OF (WIN_CERTIFICATE_UEFI_GUID, CertData);
+ DescriptorData->AuthInfo.Hdr.wRevision = 0x0200;
+ DescriptorData->AuthInfo.Hdr.wCertificateType = WIN_CERT_TYPE_EFI_GUID;
+ CopyGuid (&DescriptorData->AuthInfo.CertType, &gEfiCertPkcs7Guid);
+
+ if (Payload != NULL) {
+ FreePool(Payload);
+ }
+
+ *DataSize = DescriptorSize + PayloadSize;
+ *Data = NewData;
+ return EFI_SUCCESS;
+}
+
+/**
+ Internal helper function to delete a Variable given its name and GUID, NO authentication
+ required.
+
+ @param[in] VariableName Name of the Variable.
+ @param[in] VendorGuid GUID of the Variable.
+
+ @retval EFI_SUCCESS Variable deleted successfully.
+ @retval Others The driver failed to start the device.
+
+--*/
+EFI_STATUS
+DeleteVariable (
+ IN CHAR16 *VariableName,
+ IN EFI_GUID *VendorGuid
+ )
+{
+ EFI_STATUS Status;
+ VOID* Variable;
+ UINT8 *Data;
+ UINTN DataSize;
+ UINT32 Attr;
+
+ GetVariable2 (VariableName, VendorGuid, &Variable, NULL);
+ if (Variable == NULL) {
+ return EFI_SUCCESS;
+ }
+ FreePool (Variable);
+
+ Data = NULL;
+ DataSize = 0;
+ Attr = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS
+ | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
+
+ Status = CreateTimeBasedPayload (&DataSize, &Data);
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Fail to create time-based data payload: %r", Status));
+ return Status;
+ }
+
+ Status = gRT->SetVariable (
+ VariableName,
+ VendorGuid,
+ Attr,
+ DataSize,
+ Data
+ );
+ if (Data != NULL) {
+ FreePool (Data);
+ }
+ return Status;
+}
+
+/**
+
+ 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
+ )
+{
+ return gRT->SetVariable (
+ EFI_CUSTOM_MODE_NAME,
+ &gEfiCustomModeEnableGuid,
+ EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,
+ sizeof (UINT8),
+ &SecureBootMode
+ );
+}
+
+/**
+ Fetches the value of SetupMode variable.
+
+ @param[out] SetupMode Pointer to UINT8 for SetupMode output
+
+ @retval other Retval from GetVariable.
+--*/
+EFI_STATUS
+EFIAPI
+GetSetupMode (
+ OUT UINT8 *SetupMode
+)
+{
+ UINTN Size;
+ EFI_STATUS Status;
+
+ Size = sizeof (*SetupMode);
+ Status = gRT->GetVariable (
+ EFI_SETUP_MODE_NAME,
+ &gEfiGlobalVariableGuid,
+ NULL,
+ &Size,
+ SetupMode
+ );
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ 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
+)
+{
+ EFI_STATUS Status;
+
+ Status = DeleteVariable (
+ EFI_IMAGE_SECURITY_DATABASE,
+ &gEfiImageSecurityDatabaseGuid
+ );
+
+ return Status;
+}
+
+/**
+ 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
+)
+{
+ EFI_STATUS Status;
+
+ Status = DeleteVariable (
+ EFI_IMAGE_SECURITY_DATABASE1,
+ &gEfiImageSecurityDatabaseGuid
+ );
+
+ return Status;
+}
+
+/**
+ 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
+)
+{
+ EFI_STATUS Status;
+
+ Status = DeleteVariable (
+ EFI_IMAGE_SECURITY_DATABASE2,
+ &gEfiImageSecurityDatabaseGuid
+ );
+
+ return Status;
+}
+
+/**
+ 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
+)
+{
+ EFI_STATUS Status;
+
+ Status = DeleteVariable (
+ EFI_KEY_EXCHANGE_KEY_NAME,
+ &gEfiGlobalVariableGuid
+ );
+
+ return Status;
+}
+
+/**
+ Remove the PK variable.
+
+ @retval EFI_SUCCESS Delete PK successfully.
+ @retval Others Could not allow to delete PK.
+
+--*/
+EFI_STATUS
+EFIAPI
+DeletePlatformKey (
+ VOID
+)
+{
+ EFI_STATUS Status;
+
+ Status = SetSecureBootMode(CUSTOM_SECURE_BOOT_MODE);
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+
+ Status = DeleteVariable (
+ EFI_PLATFORM_KEY_NAME,
+ &gEfiGlobalVariableGuid
+ );
+ return Status;
+}
diff --git a/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.uni b/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.uni
new file mode 100644
index 0000000000..2d5fb7cbb8
--- /dev/null
+++ b/SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.uni
@@ -0,0 +1,17 @@
+// /** @file
+//
+// Provides helper function for initialization of Secure Boot
+// keys and databases.
+//
+// Copyright (c) 2021, ARM Ltd. All rights reserved.<BR>
+// Copyright (c) 2021, Semihalf All rights reserved.<BR>
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+// **/
+
+
+#string STR_MODULE_ABSTRACT #language en-US "Provides helper functions to initialize PK, KEK and databases based on default variables."
+
+#string STR_MODULE_DESCRIPTION #language en-US "Provides helper functions to initialize PK, KEK and databases based on default variables."
+
--
2.25.1