/**
This code gets the pointer to the variable name.
@param Variable Pointer to the Variable Header.
@param AuthFlag Authenticated variable flag.
@return A CHAR16* pointer to Variable Name.
**/
CHAR16 *
GetVariableNamePtr (
IN VARIABLE_HEADER *Variable,
IN BOOLEAN AuthFlag
)
{
return (CHAR16 *) ((UINTN) Variable + GetVariableHeaderSize (AuthFlag));
}
/**
Variable Driver main entry point. The Variable driver places the 4 EFI
runtime services in the EFI System Table and installs arch protocols
for variable read and write services being available. It also registers
a notification function for an EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
@param[in] ImageHandle The firmware allocated handle for the EFI image.
@param[in] SystemTable A pointer to the EFI System Table.
@retval EFI_SUCCESS Variable service successfully initialized.
**/
EFI_STATUS
EFIAPI
VariableServiceInitialize (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
EFI_HANDLE VariableHandle;
VOID *SmmFtwRegistration;
VOID *SmmEndOfDxeRegistration;
//
// Variable initialize.
//
Status = VariableCommonInitialize ();
ASSERT_EFI_ERROR (Status);
//
// Install the Smm Variable Protocol on a new handle.
//
VariableHandle = NULL;
Status = gSmst->SmmInstallProtocolInterface (
&VariableHandle,
&gEfiSmmVariableProtocolGuid,
EFI_NATIVE_INTERFACE,
&gSmmVariable
);
ASSERT_EFI_ERROR (Status);
Status = gSmst->SmmInstallProtocolInterface (
&VariableHandle,
&gEdkiiSmmVarCheckProtocolGuid,
EFI_NATIVE_INTERFACE,
&mSmmVarCheck
);
ASSERT_EFI_ERROR (Status);
mVariableBufferPayloadSize = GetNonVolatileMaxVariableSize () +
OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name) - GetVariableHeaderSize ();
Status = gSmst->SmmAllocatePool (
EfiRuntimeServicesData,
mVariableBufferPayloadSize,
(VOID **)&mVariableBufferPayload
);
ASSERT_EFI_ERROR (Status);
///
/// Register SMM variable SMI handler
///
VariableHandle = NULL;
Status = gSmst->SmiHandlerRegister (SmmVariableHandler, &gEfiSmmVariableProtocolGuid, &VariableHandle);
ASSERT_EFI_ERROR (Status);
//
// Notify the variable wrapper driver the variable service is ready
//
Status = SystemTable->BootServices->InstallProtocolInterface (
&mVariableHandle,
&gEfiSmmVariableProtocolGuid,
EFI_NATIVE_INTERFACE,
&gSmmVariable
);
ASSERT_EFI_ERROR (Status);
//
// Register EFI_SMM_END_OF_DXE_PROTOCOL_GUID notify function.
//
Status = gSmst->SmmRegisterProtocolNotify (
&gEfiSmmEndOfDxeProtocolGuid,
SmmEndOfDxeCallback,
&SmmEndOfDxeRegistration
);
ASSERT_EFI_ERROR (Status);
//
// Register FtwNotificationEvent () notify function.
//
Status = gSmst->SmmRegisterProtocolNotify (
&gEfiSmmFaultTolerantWriteProtocolGuid,
SmmFtwNotificationEvent,
&SmmFtwRegistration
);
ASSERT_EFI_ERROR (Status);
SmmFtwNotificationEvent (NULL, NULL, NULL);
return EFI_SUCCESS;
}
/**
Get variable header that has consecutive content.
@param StoreInfo Pointer to variable store info structure.
@param Variable Pointer to the Variable Header.
@param VariableHeader Pointer to Pointer to the Variable Header that has consecutive content.
@retval TRUE Variable header is valid.
@retval FALSE Variable header is not valid.
**/
BOOLEAN
GetVariableHeader (
IN VARIABLE_STORE_INFO *StoreInfo,
IN VARIABLE_HEADER *Variable,
OUT VARIABLE_HEADER **VariableHeader
)
{
EFI_PHYSICAL_ADDRESS TargetAddress;
EFI_PHYSICAL_ADDRESS SpareAddress;
EFI_HOB_GUID_TYPE *GuidHob;
UINTN PartialHeaderSize;
if (Variable == NULL) {
return FALSE;
}
//
// First assume variable header pointed by Variable is consecutive.
//
*VariableHeader = Variable;
if (StoreInfo->FtwLastWriteData != NULL) {
TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
SpareAddress = StoreInfo->FtwLastWriteData->SpareAddress;
if (((UINTN) Variable > (UINTN) SpareAddress) &&
(((UINTN) Variable - (UINTN) SpareAddress + (UINTN) TargetAddress) >= (UINTN) GetEndPointer (StoreInfo->VariableStoreHeader))) {
//
// Reach the end of variable store.
//
return FALSE;
}
if (((UINTN) Variable < (UINTN) TargetAddress) && (((UINTN) Variable + GetVariableHeaderSize (StoreInfo->AuthFlag)) > (UINTN) TargetAddress)) {
//
// Variable header pointed by Variable is inconsecutive,
// create a guid hob to combine the two partial variable header content together.
//
GuidHob = GetFirstGuidHob (&gEfiCallerIdGuid);
if (GuidHob != NULL) {
*VariableHeader = (VARIABLE_HEADER *) GET_GUID_HOB_DATA (GuidHob);
} else {
*VariableHeader = (VARIABLE_HEADER *) BuildGuidHob (&gEfiCallerIdGuid, GetVariableHeaderSize (StoreInfo->AuthFlag));
PartialHeaderSize = (UINTN) TargetAddress - (UINTN) Variable;
//
// Partial content is in NV storage.
//
CopyMem ((UINT8 *) *VariableHeader, (UINT8 *) Variable, PartialHeaderSize);
//
// Another partial content is in spare block.
//
CopyMem ((UINT8 *) *VariableHeader + PartialHeaderSize, (UINT8 *) (UINTN) SpareAddress, GetVariableHeaderSize (StoreInfo->AuthFlag) - PartialHeaderSize);
}
}
} else {
if (Variable >= GetEndPointer (StoreInfo->VariableStoreHeader)) {
//
// Reach the end of variable store.
//
return FALSE;
}
}
return IsValidVariableHeader (*VariableHeader);
}
