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-rw-r--r--Lessons/Lesson_55/README.md272
-rw-r--r--Lessons/Lesson_55/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c71
-rw-r--r--Lessons/Lesson_55/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf27
-rw-r--r--Lessons/Lesson_55/UefiLessonsPkg/UefiLessonsPkg.dec45
-rw-r--r--Lessons/Lesson_55/UefiLessonsPkg/UefiLessonsPkg.dsc78
-rw-r--r--README.md1
-rw-r--r--UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c71
-rw-r--r--UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf27
-rw-r--r--UefiLessonsPkg/UefiLessonsPkg.dsc1
9 files changed, 593 insertions, 0 deletions
diff --git a/Lessons/Lesson_55/README.md b/Lessons/Lesson_55/README.md
new file mode 100644
index 0000000..123f439
--- /dev/null
+++ b/Lessons/Lesson_55/README.md
@@ -0,0 +1,272 @@
+We know how to add font for the new language, and we now how to populate strings for some of the existing languages in the system dynamically.
+Let's see if it is possible to create another language option dynamically.
+
+`Select Language` menu gets all possible language options from the value of the `PlatformLangCodes` EFI variable. And the current language option is reflected by the `PlatformLang` EFI option.
+
+Initially the values for these options are set with a help of PCD in the https://github.com/tianocore/edk2/blob/master/MdePkg/MdePkg.dec:
+```
+ ## Default platform supported RFC 4646 languages: (American) English & French.
+ # @Prompt Default Value of PlatformLangCodes Variable.
+ gEfiMdePkgTokenSpaceGuid.PcdUefiVariableDefaultPlatformLangCodes|"en;fr;en-US;fr-FR"|VOID*|0x0000001e
+
+ ## Default current RFC 4646 language: (American) English.
+ # @Prompt Default Value of PlatformLang Variable.
+ gEfiMdePkgTokenSpaceGuid.PcdUefiVariableDefaultPlatformLang|"en-US"|VOID*|0x0000001f
+```
+You can look at the actual code in the `UiCreateLanguageMenu` function from the https://github.com/tianocore/edk2/blob/master/MdeModulePkg/Application/UiApp/FrontPageCustomizedUiSupport.c.
+
+Let's see if it is possible to modify `PlatformLangCodes` and add another language into it.
+
+First create an app that would print the value for the `PlatformLangCodes` option:
+```
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+
+ CHAR8* LanguageString;
+ Status = GetEfiGlobalVariable2(L"PlatformLangCodes", (VOID**)&LanguageString, NULL);
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't perform GetEfiGlobalVariable2, status=%r\n", Status);
+ return Status;
+ }
+ Print(L"Current value of the 'PlatformLangCodes' variable is '%a'\n", LanguageString);
+
+ return EFI_SUCCESS;
+}
+```
+We've already used `gRT->GetVariable` protocol function directly before, so here we use `GetEfiGlobalVariable2` library function to the simplify code. This function is defined in the https://github.com/tianocore/edk2/blob/master/MdePkg/Library/UefiLib/UefiLib.c:
+```
+**
+ Returns a pointer to an allocated buffer that contains the contents of a
+ variable retrieved through the UEFI Runtime Service GetVariable(). This
+ function always uses the EFI_GLOBAL_VARIABLE GUID to retrieve variables.
+ The returned buffer is allocated using AllocatePool(). The caller is
+ responsible for freeing this buffer with FreePool().
+ If Name is NULL, then ASSERT().
+ If Value is NULL, then ASSERT().
+ @param[in] Name The pointer to a Null-terminated Unicode string.
+ @param[out] Value The buffer point saved the variable info.
+ @param[out] Size The buffer size of the variable.
+ @return EFI_OUT_OF_RESOURCES Allocate buffer failed.
+ @return EFI_SUCCESS Find the specified variable.
+ @return Others Errors Return errors from call to gRT->GetVariable.
+**/
+EFI_STATUS
+EFIAPI
+GetEfiGlobalVariable2 (
+ IN CONST CHAR16 *Name,
+ OUT VOID **Value,
+ OUT UINTN *Size OPTIONAL
+ )
+```
+
+If you build and run our application now, you would get the value from the PCD:
+```
+FS0:\> AddNewLanguage.efi
+Current value of the 'PlatformLangCodes' variable is 'en;fr;en-US;fr-FR'
+```
+
+Now let's try to add `;ru-RU` to the end of the variable and write it back.
+
+First construct new string and fill it with the necessary data:
+```
+CHAR8* NewLanguageString = AllocatePool(AsciiStrLen(LanguageString) + AsciiStrSize(";ru-RU"));
+if (NewLanguageString == NULL) {
+ Print(L"Error! Can't allocate size for new PlatformLangCodes variable\n");
+ FreePool(LanguageString);
+ return EFI_OUT_OF_RESOURCES;
+}
+
+CopyMem(NewLanguageString, LanguageString, AsciiStrLen(LanguageString));
+CopyMem(&NewLanguageString[AsciiStrLen(LanguageString)], ";ru-RU", AsciiStrSize(";ru-RU"));
+
+Print(L"Set 'PlatformLangCodes' variable to '%a'\n", NewLanguageString);
+```
+Just in case ASCII string functions are defined in the https://github.com/tianocore/edk2/blob/master/MdePkg/Library/BaseLib/String.c.
+Also don't forget to include `Library/MemoryAllocationLib.h` header for the `AllocatePool` function and `Library/BaseMemoryLib.h` header for the `CopyMem` function.
+
+Now use `SetVariable` call to update variable:
+```
+Status = gRT->SetVariable (
+ L"PlatformLangCodes",
+ &gEfiGlobalVariableGuid,
+ EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
+ AsciiStrSize(NewLanguageString),
+ NewLanguageString
+ );
+if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't set 'PlatformLangCodes' variable, status=%r\n", Status);
+}
+```
+`SetVariable` is a Runtime Service, you can find its definition in the UEFI specification:
+```
+SetVariable()
+
+Summary:
+Sets the value of a variable.
+
+Prototype:
+typedef
+EFI_STATUS
+SetVariable (
+ IN CHAR16 *VariableName,
+ IN EFI_GUID *VendorGuid,
+ IN UINT32 Attributes,
+ IN UINTN DataSize,
+ IN VOID *Data
+ );
+
+Parameters:
+VariableName A Null-terminated string that is the name of the vendor’s variable. Each VariableName is unique for each VendorGuid.
+VendorGuid A unique identifier for the vendor.
+Attributes Attributes bitmask to set for the variable.
+DataSize The size in bytes of the Data buffer.
+Data The contents for the variable.
+```
+In case you forgot `gRT` is a shortcut for the `SystemTable->RuntimeServices` from the `UefiRuntimeServicesTableLib` library. So don't forget to include its library header `<Library/UefiRuntimeServicesTableLib.h>`.
+
+If you build and run our application now you would get:
+```
+FS0:\> AddNewLanguage.efi
+Current value of the 'PlatformLangCodes' variable is 'en;fr;en-US;fr-FR'
+Set 'PlatformLangCodes' variable to 'en;fr;en-US;fr-FR;ru-RU'
+Error! Can't set 'PlatformLangCodes' variable, status=Write Protected
+```
+
+Unfortunately it is not possible to add new language at runtime as 'PlatformLangCodes' EFI variable is write protected. Therefore it is not possible to add another localization language at runtime.
+
+If you look at the UEFI spec you'll see:
+```
+The PlatformLangCodes variable contains a null- terminated ASCII string representing the language
+codes that the firmware can support. At initialization time the firmware computes the supported
+languages and creates this data variable. Since the firmware creates this value on each initialization, its
+contents are not stored in nonvolatile memory. This value is considered read-only.
+```
+
+# EDKII_VARIABLE_POLICY_PROTOCOL
+
+The `PlatformLangCodes` is locked for modifications with a help of a `gEdkiiVariablePolicyProtocolGuid` protocol. This is a custom EDKII protocol for setting different policies on variables.
+
+You can read more about the UEFI Variable Policy protocol in the https://github.com/tianocore/edk2/tree/master/MdeModulePkg/Library/VariablePolicyLib/ReadMe.md
+
+The header file is placed under https://github.com/tianocore/edk2/blob/master/MdeModulePkg/Include/Protocol/VariablePolicy.h
+
+The policy for the `PlatformLangCodes` EFI variable is set in the https://github.com/tianocore/edk2/blob/master/MdeModulePkg/Universal/BdsDxe/BdsEntry.c along with couple of other variables:
+```
+///
+/// The read-only variables defined in UEFI Spec.
+///
+CHAR16 *mReadOnlyVariables[] = {
+ EFI_PLATFORM_LANG_CODES_VARIABLE_NAME, // L"PlatformLangCodes" The language codes that the firmware supports
+ EFI_LANG_CODES_VARIABLE_NAME,
+ EFI_BOOT_OPTION_SUPPORT_VARIABLE_NAME,
+ EFI_HW_ERR_REC_SUPPORT_VARIABLE_NAME,
+ EFI_OS_INDICATIONS_SUPPORT_VARIABLE_NAME
+ };
+
+...
+
+ // Mark the read-only variables if the Variable Lock protocol exists
+ //
+ Status = gBS->LocateProtocol(&gEdkiiVariablePolicyProtocolGuid,
+NULL, (VOID**)&VariablePolicy);
+ DEBUG((DEBUG_INFO, "[BdsDxe] Locate Variable Policy protocol -
+%r\n", Status));
+ if (!EFI_ERROR (Status)) {
+ for (Index = 0; Index < ARRAY_SIZE (mReadOnlyVariables); Index++) {
+ Status = RegisterBasicVariablePolicy(
+ VariablePolicy,
+ &gEfiGlobalVariableGuid,
+ mReadOnlyVariables[Index],
+ VARIABLE_POLICY_NO_MIN_SIZE,
+ VARIABLE_POLICY_NO_MAX_SIZE,
+ VARIABLE_POLICY_NO_MUST_ATTR,
+ VARIABLE_POLICY_NO_CANT_ATTR,
+ VARIABLE_POLICY_TYPE_LOCK_NOW
+ );
+ ASSERT_EFI_ERROR(Status);
+ }
+ }
+```
+
+# Try to execute DisableVariablePolicy()
+
+We can try to perform `DisableVariablePolicy()` to disable `VariablePolicyProtocol`.
+
+UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c
+```
+...
+#include <Protocol/VariablePolicy.h>
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ ...
+
+ EDKII_VARIABLE_POLICY_PROTOCOL* VariablePolicyProtocol;
+ Status = gBS->LocateProtocol(&gEdkiiVariablePolicyProtocolGuid,
+ NULL,
+ (VOID**)&VariablePolicyProtocol);
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Could not find Variable Policy protocol: %r\n", Status);
+ return Status;
+ }
+ Status = VariablePolicyProtocol->DisableVariablePolicy();
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't disable VariablePolicy: %r\n", Status);
+ return Status;
+ }
+}
+```
+
+UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf:
+```
+....
+[Packages]
+ ...
+ MdeModulePkg/MdeModulePkg.dec
+...
+
+[Protocols]
+ gEdkiiVariablePolicyProtocolGuid
+```
+
+But unfortunately this call would fail:
+```
+FS0:\> AddNewLanguage.efi
+Current value of the 'PlatformLangCodes' variable is 'en;fr;en-US;fr-FR'
+Set 'PlatformLangCodes' variable to 'en;fr;en-US;fr-FR;ru-RU'
+Error! Can't set PlatformLangCodes variable, status=Write Protected
+Error! Can't disable VariablePolicy: Write Protected
+```
+
+This happend because in the end of the DXE UEFI stage variable policy is locked in the MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c:
+```
+VOID
+EFIAPI
+OnEndOfDxe (
+ EFI_EVENT Event,
+ VOID *Context
+)
+{
+ EFI_STATUS Status;
+ DEBUG ((EFI_D_INFO, "[Variable]END_OF_DXE is signaled\n"));
+ ...
+ Status = LockVariablePolicy ();
+ ...
+}
+```
+Locking means that is no longer possible to change or disable policy for variables. Therefore there is no way to change `PlatformLangCodes` at runtime.
+
diff --git a/Lessons/Lesson_55/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c b/Lessons/Lesson_55/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c
new file mode 100644
index 0000000..cd4920d
--- /dev/null
+++ b/Lessons/Lesson_55/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2021, Konstantin Aladyshev <aladyshev22@gmail.com>
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+#include <Library/MemoryAllocationLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+#include <Protocol/VariablePolicy.h>
+
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+
+ CHAR8* LanguageString;
+ Status = GetEfiGlobalVariable2(L"PlatformLangCodes", (VOID**)&LanguageString, NULL);
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't perform GetEfiGlobalVariable2, status=%r\n", Status);
+ return Status;
+ }
+ Print(L"Current value of the 'PlatformLangCodes' variable is '%a'\n", LanguageString);
+
+ CHAR8* NewLanguageString = AllocatePool(AsciiStrLen(LanguageString) + AsciiStrSize(";ru-RU"));
+ if (NewLanguageString == NULL) {
+ Print(L"Error! Can't allocate size for new PlatformLangCodes variable\n");
+ FreePool(LanguageString);
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ CopyMem(NewLanguageString, LanguageString, AsciiStrLen(LanguageString));
+ CopyMem(&NewLanguageString[AsciiStrLen(LanguageString)], ";ru-RU", AsciiStrSize(";ru-RU"));
+
+ Print(L"Set 'PlatformLangCodes' variable to '%a'\n", NewLanguageString);
+
+ Status = gRT->SetVariable (
+ L"PlatformLangCodes",
+ &gEfiGlobalVariableGuid,
+ EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
+ AsciiStrSize(NewLanguageString),
+ NewLanguageString
+ );
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't set PlatformLangCodes variable, status=%r\n", Status);
+ }
+
+ EDKII_VARIABLE_POLICY_PROTOCOL* VariablePolicyProtocol;
+ Status = gBS->LocateProtocol(&gEdkiiVariablePolicyProtocolGuid,
+ NULL,
+ (VOID**)&VariablePolicyProtocol);
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Could not find Variable Policy protocol: %r\n", Status);
+ return Status;
+ }
+ Status = VariablePolicyProtocol->DisableVariablePolicy();
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't disable VariablePolicy: %r\n", Status);
+ return Status;
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/Lessons/Lesson_55/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf b/Lessons/Lesson_55/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf
new file mode 100644
index 0000000..1a34438
--- /dev/null
+++ b/Lessons/Lesson_55/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf
@@ -0,0 +1,27 @@
+##
+# Copyright (c) 2021, Konstantin Aladyshev <aladyshev22@gmail.com>
+#
+# SPDX-License-Identifier: MIT
+##
+
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = AddNewLanguage
+ FILE_GUID = 6790e268-0762-4ce8-8999-2ff2131e6512
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = UefiMain
+
+[Sources]
+ AddNewLanguage.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+ MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+
+[Protocols]
+ gEdkiiVariablePolicyProtocolGuid
diff --git a/Lessons/Lesson_55/UefiLessonsPkg/UefiLessonsPkg.dec b/Lessons/Lesson_55/UefiLessonsPkg/UefiLessonsPkg.dec
new file mode 100644
index 0000000..40b351c
--- /dev/null
+++ b/Lessons/Lesson_55/UefiLessonsPkg/UefiLessonsPkg.dec
@@ -0,0 +1,45 @@
+##
+# Copyright (c) 2021, Konstantin Aladyshev <aladyshev22@gmail.com>
+#
+# SPDX-License-Identifier: MIT
+##
+
+[Defines]
+ DEC_SPECIFICATION = 0x00010005
+ PACKAGE_NAME = UefiLessonsPkg
+ PACKAGE_GUID = 7e7edbba-ca2c-4177-a3f0-d3371358773a
+ PACKAGE_VERSION = 1.01
+
+[Includes]
+ Include
+
+[Guids]
+ # FILE_GUID as defined in UefiLessonsPkg/HelloWorld/HelloWorld.inf
+ gHelloWorldFileGuid = {0x2e55fa38, 0xf148, 0x42d3, {0xaf, 0x90, 0x1b, 0xe2, 0x47, 0x32, 0x3e, 0x30}}
+ gUefiLessonsPkgTokenSpaceGuid = {0x150cab53, 0xad47, 0x4385, {0xb5, 0xdd, 0xbc, 0xfc, 0x76, 0xba, 0xca, 0xf0}}
+ gHIIStringsCGuid = { 0x8e0b8ed3, 0x14f7, 0x499d, { 0xa2, 0x24, 0xae, 0xe8, 0x9d, 0xc9, 0x7f, 0xa3 }}
+ gHIIStringsUNIGuid = { 0x6ee19058, 0x0fe2, 0x44ed, { 0x89, 0x1c, 0xa5, 0xd7, 0xe1, 0x08, 0xee, 0x1a }}
+ gHIIStringsUNIRCGuid = { 0x785693b4, 0x623e, 0x40fa, { 0x9a, 0x45, 0x68, 0xda, 0x38, 0x30, 0x89, 0xdd }}
+ gHIIAddRussianFontGuid = { 0x9fe2f616, 0x323c, 0x45a7, { 0x87, 0xa2, 0xdf, 0xef, 0xf5, 0x17, 0xcc, 0x66 }}
+
+[Protocols]
+ gSimpleClassProtocolGuid = { 0xb5510eea, 0x6f11, 0x4e4b, { 0xad, 0x0f, 0x35, 0xce, 0x17, 0xbd, 0x7a, 0x67 }}
+
+[PcdsFixedAtBuild]
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyVar32|42|UINT32|0x00000001
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyVar32_1|42|UINT32|0x00000002
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyVar32_2|42|UINT32|0x00000003
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyVarBool|FALSE|BOOLEAN|0x00000004
+
+[PcdsPatchableInModule]
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyPatchableVar32|0x31313131|UINT32|0x10000001
+
+[PcdsFeatureFlag]
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyFeatureFlagVar|FALSE|BOOLEAN|0x20000001
+
+[PcdsDynamic]
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyDynamicVar32|0x38323232|UINT32|0x30000001
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyDynamicVar32_1|42|UINT32|0x30000002
+
+[PcdsDynamicEx]
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyDynamicExVar32|0x38333333|UINT32|0x40000001
diff --git a/Lessons/Lesson_55/UefiLessonsPkg/UefiLessonsPkg.dsc b/Lessons/Lesson_55/UefiLessonsPkg/UefiLessonsPkg.dsc
new file mode 100644
index 0000000..85ea19a
--- /dev/null
+++ b/Lessons/Lesson_55/UefiLessonsPkg/UefiLessonsPkg.dsc
@@ -0,0 +1,78 @@
+##
+# Copyright (c) 2021, Konstantin Aladyshev <aladyshev22@gmail.com>
+#
+# SPDX-License-Identifier: MIT
+##
+
+[Defines]
+ DSC_SPECIFICATION = 0x0001001C
+ PLATFORM_GUID = 3db7270f-ffac-4139-90a4-0ae68f3f8167
+ PLATFORM_VERSION = 0.01
+ PLATFORM_NAME = UefiLessonsPkg
+ SKUID_IDENTIFIER = DEFAULT
+ SUPPORTED_ARCHITECTURES = X64
+ BUILD_TARGETS = RELEASE
+
+
+[LibraryClasses]
+ UefiApplicationEntryPoint|MdePkg/Library/UefiApplicationEntryPoint/UefiApplicationEntryPoint.inf
+ UefiBootServicesTableLib|MdePkg/Library/UefiBootServicesTableLib/UefiBootServicesTableLib.inf
+ DebugLib|MdePkg/Library/UefiDebugLibConOut/UefiDebugLibConOut.inf
+ BaseLib|MdePkg/Library/BaseLib/BaseLib.inf
+ #PcdLib|MdePkg/Library/BasePcdLibNull/BasePcdLibNull.inf
+ PcdLib|MdePkg/Library/DxePcdLib/DxePcdLib.inf
+ BaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf
+ RegisterFilterLib|MdePkg/Library/RegisterFilterLibNull/RegisterFilterLibNull.inf
+ PrintLib|MdePkg/Library/BasePrintLib/BasePrintLib.inf
+ DebugPrintErrorLevelLib|MdePkg/Library/BaseDebugPrintErrorLevelLib/BaseDebugPrintErrorLevelLib.inf
+ UefiLib|MdePkg/Library/UefiLib/UefiLib.inf
+ MemoryAllocationLib|MdePkg/Library/UefiMemoryAllocationLib/UefiMemoryAllocationLib.inf
+ DevicePathLib|MdePkg/Library/UefiDevicePathLib/UefiDevicePathLib.inf
+ UefiRuntimeServicesTableLib|MdePkg/Library/UefiRuntimeServicesTableLib/UefiRuntimeServicesTableLib.inf
+ ShellCEntryLib|ShellPkg/Library/UefiShellCEntryLib/UefiShellCEntryLib.inf
+ ShellLib|ShellPkg/Library/UefiShellLib/UefiShellLib.inf
+ FileHandleLib|MdePkg/Library/UefiFileHandleLib/UefiFileHandleLib.inf
+ HiiLib|MdeModulePkg/Library/UefiHiiLib/UefiHiiLib.inf
+ SortLib|MdeModulePkg/Library/UefiSortLib/UefiSortLib.inf
+ UefiHiiServicesLib|MdeModulePkg/Library/UefiHiiServicesLib/UefiHiiServicesLib.inf
+ UefiDriverEntryPoint|MdePkg/Library/UefiDriverEntryPoint/UefiDriverEntryPoint.inf
+ #SimpleLibrary|UefiLessonsPkg/Library/SimpleLibrary/SimpleLibrary.inf
+ #SimpleLibrary|UefiLessonsPkg/Library/SimpleLibraryWithConstructor/SimpleLibraryWithConstructor.inf
+ SimpleLibrary|UefiLessonsPkg/Library/SimpleLibraryWithConstructorAndDestructor/SimpleLibraryWithConstructorAndDestructor.inf
+
+[Components]
+ UefiLessonsPkg/SimplestApp/SimplestApp.inf
+ UefiLessonsPkg/HelloWorld/HelloWorld.inf
+ UefiLessonsPkg/ImageHandle/ImageHandle.inf
+ UefiLessonsPkg/ImageInfo/ImageInfo.inf
+ UefiLessonsPkg/MemoryInfo/MemoryInfo.inf
+ UefiLessonsPkg/SimpleShellApp/SimpleShellApp.inf
+ UefiLessonsPkg/ListVariables/ListVariables.inf
+ UefiLessonsPkg/ShowBootVariables/ShowBootVariables.inf
+ UefiLessonsPkg/InteractiveApp/InteractiveApp.inf
+ UefiLessonsPkg/PCDLesson/PCDLesson.inf
+ UefiLessonsPkg/SmbiosInfo/SmbiosInfo.inf
+ UefiLessonsPkg/ShowTables/ShowTables.inf
+ UefiLessonsPkg/AcpiInfo/AcpiInfo.inf
+ UefiLessonsPkg/SaveBGRT/SaveBGRT.inf
+ UefiLessonsPkg/ListPCI/ListPCI.inf
+ UefiLessonsPkg/SimpleDriver/SimpleDriver.inf
+ UefiLessonsPkg/PCIRomInfo/PCIRomInfo.inf
+ UefiLessonsPkg/Library/SimpleLibrary/SimpleLibrary.inf
+ UefiLessonsPkg/Library/SimpleLibraryWithConstructor/SimpleLibraryWithConstructor.inf
+ UefiLessonsPkg/SimpleLibraryUser/SimpleLibraryUser.inf
+ UefiLessonsPkg/SimpleClassProtocol/SimpleClassProtocol.inf
+ UefiLessonsPkg/SimpleClassUser/SimpleClassUser.inf
+ UefiLessonsPkg/HotKeyDriver/HotKeyDriver.inf
+ UefiLessonsPkg/ShowHII/ShowHII.inf
+ UefiLessonsPkg/HIIStringsC/HIIStringsC.inf
+ UefiLessonsPkg/HIIStringsUNI/HIIStringsUNI.inf
+ UefiLessonsPkg/HIIStringsUNIRC/HIIStringsUNIRC.inf
+ UefiLessonsPkg/HIIStringsMan/HIIStringsMan.inf
+ UefiLessonsPkg/HIIAddRussianFont/HIIAddRussianFont.inf
+ UefiLessonsPkg/HIIAddLocalization/HIIAddLocalization.inf
+ UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf
+
+[PcdsFixedAtBuild]
+ gUefiLessonsPkgTokenSpaceGuid.PcdMyVar32_2|44
+
diff --git a/README.md b/README.md
index 81df75b..e39595d 100644
--- a/README.md
+++ b/README.md
@@ -58,6 +58,7 @@ These series of lessons are intendend to get you started with UEFI programming i
- [Lesson 52](Lessons/Lesson_52): Add Russian font - Part 1: investigate `EFI_NARROW_GLYPH`/`EFI_WIDE_GLYPH` format, construct glyph array from the *.woff font file
- [Lesson 53](Lessons/Lesson_53): Add Russian font - Part 2: construct `EFI_HII_SIMPLE_FONT_PACKAGE` and populate it to the HII database
- [Lesson 54](Lessons/Lesson_54): Use `NewString` and `SetString` functions from the `EFI_HII_STRING_PROTOCOL` to add String Package for another language dynamically
+- [Lesson 55](Lessons/Lesson_55): Try to modify `PlatformLangCodes` EFI variable and add another language dynamically. Variable protection with a help of `EDKII_VARIABLE_POLICY_PROTOCOL`
_____
diff --git a/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c b/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c
new file mode 100644
index 0000000..cd4920d
--- /dev/null
+++ b/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.c
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2021, Konstantin Aladyshev <aladyshev22@gmail.com>
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+#include <Library/MemoryAllocationLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+#include <Protocol/VariablePolicy.h>
+
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+
+ CHAR8* LanguageString;
+ Status = GetEfiGlobalVariable2(L"PlatformLangCodes", (VOID**)&LanguageString, NULL);
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't perform GetEfiGlobalVariable2, status=%r\n", Status);
+ return Status;
+ }
+ Print(L"Current value of the 'PlatformLangCodes' variable is '%a'\n", LanguageString);
+
+ CHAR8* NewLanguageString = AllocatePool(AsciiStrLen(LanguageString) + AsciiStrSize(";ru-RU"));
+ if (NewLanguageString == NULL) {
+ Print(L"Error! Can't allocate size for new PlatformLangCodes variable\n");
+ FreePool(LanguageString);
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ CopyMem(NewLanguageString, LanguageString, AsciiStrLen(LanguageString));
+ CopyMem(&NewLanguageString[AsciiStrLen(LanguageString)], ";ru-RU", AsciiStrSize(";ru-RU"));
+
+ Print(L"Set 'PlatformLangCodes' variable to '%a'\n", NewLanguageString);
+
+ Status = gRT->SetVariable (
+ L"PlatformLangCodes",
+ &gEfiGlobalVariableGuid,
+ EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
+ AsciiStrSize(NewLanguageString),
+ NewLanguageString
+ );
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't set PlatformLangCodes variable, status=%r\n", Status);
+ }
+
+ EDKII_VARIABLE_POLICY_PROTOCOL* VariablePolicyProtocol;
+ Status = gBS->LocateProtocol(&gEdkiiVariablePolicyProtocolGuid,
+ NULL,
+ (VOID**)&VariablePolicyProtocol);
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Could not find Variable Policy protocol: %r\n", Status);
+ return Status;
+ }
+ Status = VariablePolicyProtocol->DisableVariablePolicy();
+ if (EFI_ERROR(Status)) {
+ Print(L"Error! Can't disable VariablePolicy: %r\n", Status);
+ return Status;
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf b/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf
new file mode 100644
index 0000000..1a34438
--- /dev/null
+++ b/UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf
@@ -0,0 +1,27 @@
+##
+# Copyright (c) 2021, Konstantin Aladyshev <aladyshev22@gmail.com>
+#
+# SPDX-License-Identifier: MIT
+##
+
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = AddNewLanguage
+ FILE_GUID = 6790e268-0762-4ce8-8999-2ff2131e6512
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = UefiMain
+
+[Sources]
+ AddNewLanguage.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+ MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+
+[Protocols]
+ gEdkiiVariablePolicyProtocolGuid
diff --git a/UefiLessonsPkg/UefiLessonsPkg.dsc b/UefiLessonsPkg/UefiLessonsPkg.dsc
index 48b78ca..85ea19a 100644
--- a/UefiLessonsPkg/UefiLessonsPkg.dsc
+++ b/UefiLessonsPkg/UefiLessonsPkg.dsc
@@ -71,6 +71,7 @@
UefiLessonsPkg/HIIStringsMan/HIIStringsMan.inf
UefiLessonsPkg/HIIAddRussianFont/HIIAddRussianFont.inf
UefiLessonsPkg/HIIAddLocalization/HIIAddLocalization.inf
+ UefiLessonsPkg/AddNewLanguage/AddNewLanguage.inf
[PcdsFixedAtBuild]
gUefiLessonsPkgTokenSpaceGuid.PcdMyVar32_2|44
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-06-02 18:49:19 +0000