audk/FmpDevicePkg/FmpDxe/VariableSupport.c

848 lines
28 KiB
C

/** @file
UEFI variable support functions for Firmware Management Protocol based
firmware updates.
Copyright (c) 2016, Microsoft Corporation. All rights reserved.<BR>
Copyright (c) 2018 - 2021, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include "FmpDxe.h"
#include "VariableSupport.h"
/**
Retrieve the value of a 32-bit UEFI Variable specified by VariableName and
a GUID of gEfiCallerIdGuid.
@param[in] VariableName Pointer to the UEFI Variable name to retrieve.
@param[out] Valid Set to TRUE if UEFI Variable is present and the size
of the UEFI Variable value is 32-bits. Otherwise
FALSE.
@param[out] Value If Valid is set to TRUE, then the 32-bit value of
the UEFI Variable. Otherwise 0.
**/
static
VOID
GetFmpVariable (
IN CHAR16 *VariableName,
OUT BOOLEAN *Valid,
OUT UINT32 *Value
)
{
EFI_STATUS Status;
UINTN Size;
UINT32 *Buffer;
*Valid = FALSE;
*Value = 0;
Size = 0;
Buffer = NULL;
Status = GetVariable2 (
VariableName,
&gEfiCallerIdGuid,
(VOID **)&Buffer,
&Size
);
if (!EFI_ERROR (Status) && (Size == sizeof (*Value)) && (Buffer != NULL)) {
*Valid = TRUE;
*Value = *Buffer;
}
if (Buffer != NULL) {
FreePool (Buffer);
}
}
/**
Delete the UEFI Variable with name specified by VariableName and GUID of
gEfiCallerIdGuid. If the variable can not be deleted, then print a
DEBUG_ERROR message.
@param[in] VariableName Pointer to the UEFI Variable name to delete.
**/
static
VOID
DeleteFmpVariable (
IN CHAR16 *VariableName
)
{
EFI_STATUS Status;
BOOLEAN Valid;
UINT32 Value;
GetFmpVariable (VariableName, &Valid, &Value);
if (Valid) {
Status = gRT->SetVariable (VariableName, &gEfiCallerIdGuid, 0, 0, NULL);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to delete variable %s. Status = %r\n", mImageIdName, VariableName, Status));
} else {
DEBUG ((DEBUG_INFO, "FmpDxe(%s): Deleted variable %s\n", mImageIdName, VariableName));
}
}
}
/**
Retrieve the FMP Controller State UEFI Variable value. Return NULL if
the variable does not exist or if the size of the UEFI Variable is not the
size of FMP_CONTROLLER_STATE. The buffer for the UEFI Variable value
if allocated using the UEFI Boot Service AllocatePool().
@param[in] Private Private context structure for the managed controller.
@return Pointer to the allocated FMP Controller State. Returns NULL
if the variable does not exist or is a different size than expected.
**/
static
FMP_CONTROLLER_STATE *
GetFmpControllerState (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private
)
{
EFI_STATUS Status;
FMP_CONTROLLER_STATE *FmpControllerState;
UINTN Size;
FmpControllerState = NULL;
Size = 0;
Status = GetVariable2 (
Private->FmpStateVariableName,
&gEfiCallerIdGuid,
(VOID **)&FmpControllerState,
&Size
);
if (EFI_ERROR (Status) || (FmpControllerState == NULL)) {
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to get the controller state. Status = %r\n", mImageIdName, Status));
} else {
if (Size == sizeof (*FmpControllerState)) {
return FmpControllerState;
}
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Getting controller state returned a size different than expected. Size = 0x%x\n", mImageIdName, Size));
}
if (FmpControllerState != NULL) {
FreePool (FmpControllerState);
}
return NULL;
}
/**
Generates a Null-terminated Unicode string UEFI Variable name from a base name
and a hardware instance. If the hardware instance value is 0, then the base
name is returned. If the hardware instance value is non-zero, then the 64-bit
hardware instance value is converted to a 16 character hex string and appended
to base name. The UEFI Variable name returned is allocated using the UEFI
Boot Service AllocatePool().
@param[in] HardwareInstance 64-bit hardware instance value.
@param[in] BaseVariableName Null-terminated Unicode string that is the base
name of the UEFI Variable.
@return Pointer to the allocated UEFI Variable name. Returns NULL if the
UEFI Variable can not be allocated.
**/
static
CHAR16 *
GenerateFmpVariableName (
IN UINT64 HardwareInstance,
IN CHAR16 *BaseVariableName
)
{
UINTN Size;
CHAR16 *VariableName;
//
// Allocate Unicode string with room for BaseVariableName and a 16 digit
// hexadecimal value for the HardwareInstance value.
//
Size = StrSize (BaseVariableName) + 16 * sizeof (CHAR16);
VariableName = AllocateCopyPool (Size, BaseVariableName);
if (VariableName == NULL) {
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to generate variable name %s.\n", mImageIdName, BaseVariableName));
return VariableName;
}
if (HardwareInstance == 0) {
return VariableName;
}
UnicodeValueToStringS (
&VariableName[StrLen (BaseVariableName)],
Size,
PREFIX_ZERO | RADIX_HEX,
HardwareInstance,
16
);
return VariableName;
}
/**
Generate the names of the UEFI Variables used to store state information for
a managed controller. The UEFI Variables names are a combination of a base
name and an optional hardware instance value as a 16 character hex value. If
the hardware instance value is 0, then the 16 character hex value is not
included. These storage for the UEFI Variable names are allocated using the
UEFI Boot Service AllocatePool() and the pointers are stored in the Private.
The following are examples of variable names produces for hardware instance
value 0 and value 0x1234567812345678.
FmpVersion
FmpLsv
LastAttemptStatus
LastAttemptVersion
FmpState
FmpVersion1234567812345678
FmpLsv1234567812345678
LastAttemptStatus1234567812345678
LastAttemptVersion1234567812345678
FmpState1234567812345678
@param[in,out] Private Private context structure for the managed controller.
**/
VOID
GenerateFmpVariableNames (
IN OUT FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private
)
{
EFI_STATUS Status;
VOID *Buffer;
FMP_CONTROLLER_STATE FmpControllerState;
if (Private->VersionVariableName != NULL) {
FreePool (Private->VersionVariableName);
}
if (Private->LsvVariableName != NULL) {
FreePool (Private->LsvVariableName);
}
if (Private->LastAttemptStatusVariableName != NULL) {
FreePool (Private->LastAttemptStatusVariableName);
}
if (Private->LastAttemptVersionVariableName != NULL) {
FreePool (Private->LastAttemptVersionVariableName);
}
if (Private->FmpStateVariableName != NULL) {
FreePool (Private->FmpStateVariableName);
}
Private->VersionVariableName = GenerateFmpVariableName (
Private->Descriptor.HardwareInstance,
VARNAME_VERSION
);
Private->LsvVariableName = GenerateFmpVariableName (
Private->Descriptor.HardwareInstance,
VARNAME_LSV
);
Private->LastAttemptStatusVariableName = GenerateFmpVariableName (
Private->Descriptor.HardwareInstance,
VARNAME_LASTATTEMPTSTATUS
);
Private->LastAttemptVersionVariableName = GenerateFmpVariableName (
Private->Descriptor.HardwareInstance,
VARNAME_LASTATTEMPTVERSION
);
Private->FmpStateVariableName = GenerateFmpVariableName (
Private->Descriptor.HardwareInstance,
VARNAME_FMPSTATE
);
DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->VersionVariableName));
DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->LsvVariableName));
DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->LastAttemptStatusVariableName));
DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->LastAttemptVersionVariableName));
DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->FmpStateVariableName));
Buffer = GetFmpControllerState (Private);
if (Buffer != NULL) {
//
// FMP Controller State was found with correct size.
// Delete old variables if they exist.
//
FreePool (Buffer);
DeleteFmpVariable (Private->VersionVariableName);
DeleteFmpVariable (Private->LsvVariableName);
DeleteFmpVariable (Private->LastAttemptStatusVariableName);
DeleteFmpVariable (Private->LastAttemptVersionVariableName);
return;
}
//
// FMP Controller State was either not found or is wrong size.
// Create a new FMP Controller State variable with the correct size.
//
DEBUG ((DEBUG_INFO, "FmpDxe(%s): Create controller state\n", mImageIdName));
GetFmpVariable (
Private->VersionVariableName,
&FmpControllerState.VersionValid,
&FmpControllerState.Version
);
GetFmpVariable (
Private->LsvVariableName,
&FmpControllerState.LsvValid,
&FmpControllerState.Lsv
);
GetFmpVariable (
Private->LastAttemptStatusVariableName,
&FmpControllerState.LastAttemptStatusValid,
&FmpControllerState.LastAttemptStatus
);
GetFmpVariable (
Private->LastAttemptVersionVariableName,
&FmpControllerState.LastAttemptVersionValid,
&FmpControllerState.LastAttemptVersion
);
Status = gRT->SetVariable (
Private->FmpStateVariableName,
&gEfiCallerIdGuid,
EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,
sizeof (FmpControllerState),
&FmpControllerState
);
if (EFI_ERROR (Status)) {
//
// Failed to create FMP Controller State. In this case, do not
// delete the individual variables. They can be used again on next boot
// to create the FMP Controller State.
//
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to create controller state. Status = %r\n", mImageIdName, Status));
} else {
DeleteFmpVariable (Private->VersionVariableName);
DeleteFmpVariable (Private->LsvVariableName);
DeleteFmpVariable (Private->LastAttemptStatusVariableName);
DeleteFmpVariable (Private->LastAttemptVersionVariableName);
}
}
/**
Returns the value used to fill in the Version field of the
EFI_FIRMWARE_IMAGE_DESCRIPTOR structure that is returned by the GetImageInfo()
service of the Firmware Management Protocol. The value is read from a UEFI
variable. If the UEFI variables does not exist, then a default version value
is returned.
UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"
@param[in] Private Private context structure for the managed controller.
@return The version of the firmware image in the firmware device.
**/
UINT32
GetVersionFromVariable (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private
)
{
FMP_CONTROLLER_STATE *FmpControllerState;
UINT32 Value;
Value = DEFAULT_VERSION;
FmpControllerState = GetFmpControllerState (Private);
if (FmpControllerState != NULL) {
if (FmpControllerState->VersionValid) {
Value = FmpControllerState->Version;
DEBUG ((
DEBUG_INFO,
"FmpDxe(%s): Get variable %g %s Version %08x\n",
mImageIdName,
&gEfiCallerIdGuid,
Private->FmpStateVariableName,
Value
));
}
FreePool (FmpControllerState);
}
return Value;
}
/**
Returns the value used to fill in the LowestSupportedVersion field of the
EFI_FIRMWARE_IMAGE_DESCRIPTOR structure that is returned by the GetImageInfo()
service of the Firmware Management Protocol. The value is read from a UEFI
variable. If the UEFI variables does not exist, then a default lowest
supported version value is returned.
UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"
@param[in] Private Private context structure for the managed controller.
@return The lowest supported version of the firmware image in the firmware
device.
**/
UINT32
GetLowestSupportedVersionFromVariable (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private
)
{
FMP_CONTROLLER_STATE *FmpControllerState;
UINT32 Value;
Value = DEFAULT_LOWESTSUPPORTEDVERSION;
FmpControllerState = GetFmpControllerState (Private);
if (FmpControllerState != NULL) {
if (FmpControllerState->LsvValid) {
Value = FmpControllerState->Lsv;
DEBUG ((
DEBUG_INFO,
"FmpDxe(%s): Get variable %g %s LowestSupportedVersion %08x\n",
mImageIdName,
&gEfiCallerIdGuid,
Private->FmpStateVariableName,
Value
));
}
FreePool (FmpControllerState);
}
return Value;
}
/**
Returns the value used to fill in the LastAttemptStatus field of the
EFI_FIRMWARE_IMAGE_DESCRIPTOR structure that is returned by the GetImageInfo()
service of the Firmware Management Protocol. The value is read from a UEFI
variable. If the UEFI variables does not exist, then a default last attempt
status value is returned.
UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"
@param[in] Private Private context structure for the managed controller.
@return The last attempt status value for the most recent capsule update.
**/
UINT32
GetLastAttemptStatusFromVariable (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private
)
{
FMP_CONTROLLER_STATE *FmpControllerState;
UINT32 Value;
Value = DEFAULT_LASTATTEMPTSTATUS;
FmpControllerState = GetFmpControllerState (Private);
if (FmpControllerState != NULL) {
if (FmpControllerState->LastAttemptStatusValid) {
Value = FmpControllerState->LastAttemptStatus;
DEBUG ((
DEBUG_INFO,
"FmpDxe(%s): Get variable %g %s LastAttemptStatus %08x\n",
mImageIdName,
&gEfiCallerIdGuid,
Private->FmpStateVariableName,
Value
));
}
FreePool (FmpControllerState);
}
return Value;
}
/**
Returns the value used to fill in the LastAttemptVersion field of the
EFI_FIRMWARE_IMAGE_DESCRIPTOR structure that is returned by the GetImageInfo()
service of the Firmware Management Protocol. The value is read from a UEFI
variable. If the UEFI variables does not exist, then a default last attempt
version value is returned.
UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"
@param[in] Private Private context structure for the managed controller.
@return The last attempt version value for the most recent capsule update.
**/
UINT32
GetLastAttemptVersionFromVariable (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private
)
{
FMP_CONTROLLER_STATE *FmpControllerState;
UINT32 Value;
Value = DEFAULT_LASTATTEMPTVERSION;
FmpControllerState = GetFmpControllerState (Private);
if (FmpControllerState != NULL) {
if (FmpControllerState->LastAttemptVersionValid) {
Value = FmpControllerState->LastAttemptVersion;
DEBUG ((
DEBUG_INFO,
"FmpDxe(%s): Get variable %g %s LastAttemptVersion %08x\n",
mImageIdName,
&gEfiCallerIdGuid,
Private->FmpStateVariableName,
Value
));
}
FreePool (FmpControllerState);
}
return Value;
}
/**
Saves the version current of the firmware image in the firmware device to a
UEFI variable.
UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"
@param[in] Private Private context structure for the managed controller.
@param[in] Version The version of the firmware image in the firmware device.
**/
VOID
SetVersionInVariable (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private,
IN UINT32 Version
)
{
EFI_STATUS Status;
FMP_CONTROLLER_STATE *FmpControllerState;
BOOLEAN Update;
FmpControllerState = GetFmpControllerState (Private);
if (FmpControllerState == NULL) {
//
// Can not update value if FMP Controller State does not exist.
// This variable is guaranteed to be created by GenerateFmpVariableNames().
//
return;
}
Update = FALSE;
if (!FmpControllerState->VersionValid) {
Update = TRUE;
}
if (FmpControllerState->Version != Version) {
Update = TRUE;
}
if (!Update) {
DEBUG ((DEBUG_INFO, "FmpDxe(%s): No need to update controller state. Same value as before.\n", mImageIdName));
} else {
FmpControllerState->VersionValid = TRUE;
FmpControllerState->Version = Version;
Status = gRT->SetVariable (
Private->FmpStateVariableName,
&gEfiCallerIdGuid,
EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,
sizeof (*FmpControllerState),
FmpControllerState
);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to update controller state. Status = %r\n", mImageIdName, Status));
} else {
DEBUG ((
DEBUG_INFO,
"FmpDxe(%s): Set variable %g %s Version %08x\n",
mImageIdName,
&gEfiCallerIdGuid,
Private->FmpStateVariableName,
Version
));
}
}
FreePool (FmpControllerState);
}
/**
Saves the lowest supported version current of the firmware image in the
firmware device to a UEFI variable.
UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"
@param[in] Private Private context structure for the managed
controller.
@param[in] LowestSupportedVersion The lowest supported version of the
firmware image in the firmware device.
**/
VOID
SetLowestSupportedVersionInVariable (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private,
IN UINT32 LowestSupportedVersion
)
{
EFI_STATUS Status;
FMP_CONTROLLER_STATE *FmpControllerState;
BOOLEAN Update;
FmpControllerState = GetFmpControllerState (Private);
if (FmpControllerState == NULL) {
//
// Can not update value if FMP Controller State does not exist.
// This variable is guaranteed to be created by GenerateFmpVariableNames().
//
return;
}
Update = FALSE;
if (!FmpControllerState->LsvValid) {
Update = TRUE;
}
if (FmpControllerState->Lsv < LowestSupportedVersion) {
Update = TRUE;
}
if (!Update) {
DEBUG ((DEBUG_INFO, "FmpDxe(%s): No need to update controller state. Same value as before.\n", mImageIdName));
} else {
FmpControllerState->LsvValid = TRUE;
FmpControllerState->Lsv = LowestSupportedVersion;
Status = gRT->SetVariable (
Private->FmpStateVariableName,
&gEfiCallerIdGuid,
EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,
sizeof (*FmpControllerState),
FmpControllerState
);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to update controller state. Status = %r\n", mImageIdName, Status));
} else {
DEBUG ((
DEBUG_INFO,
"FmpDxe(%s): Set variable %g %s LowestSupportedVersion %08x\n",
mImageIdName,
&gEfiCallerIdGuid,
Private->FmpStateVariableName,
LowestSupportedVersion
));
}
}
FreePool (FmpControllerState);
}
/**
Saves the last attempt status value of the most recent FMP capsule update to a
UEFI variable.
UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"
@param[in] Private Private context structure for the managed
controller.
@param[in] LastAttemptStatus The last attempt status of the most recent FMP
capsule update.
**/
VOID
SetLastAttemptStatusInVariable (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private,
IN UINT32 LastAttemptStatus
)
{
EFI_STATUS Status;
FMP_CONTROLLER_STATE *FmpControllerState;
BOOLEAN Update;
FmpControllerState = GetFmpControllerState (Private);
if (FmpControllerState == NULL) {
//
// Can not update value if FMP Controller State does not exist.
// This variable is guaranteed to be created by GenerateFmpVariableNames().
//
return;
}
Update = FALSE;
if (!FmpControllerState->LastAttemptStatusValid) {
Update = TRUE;
}
if (FmpControllerState->LastAttemptStatus != LastAttemptStatus) {
Update = TRUE;
}
if (!Update) {
DEBUG ((DEBUG_INFO, "FmpDxe(%s): No need to update controller state. Same value as before.\n", mImageIdName));
} else {
FmpControllerState->LastAttemptStatusValid = TRUE;
FmpControllerState->LastAttemptStatus = LastAttemptStatus;
Status = gRT->SetVariable (
Private->FmpStateVariableName,
&gEfiCallerIdGuid,
EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,
sizeof (*FmpControllerState),
FmpControllerState
);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to update controller state. Status = %r\n", mImageIdName, Status));
} else {
DEBUG ((
DEBUG_INFO,
"FmpDxe(%s): Set variable %g %s LastAttemptStatus %08x\n",
mImageIdName,
&gEfiCallerIdGuid,
Private->FmpStateVariableName,
LastAttemptStatus
));
}
}
FreePool (FmpControllerState);
}
/**
Saves the last attempt version value of the most recent FMP capsule update to
a UEFI variable.
UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"
@param[in] Private Private context structure for the managed
controller.
@param[in] LastAttemptVersion The last attempt version value of the most
recent FMP capsule update.
**/
VOID
SetLastAttemptVersionInVariable (
IN FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private,
IN UINT32 LastAttemptVersion
)
{
EFI_STATUS Status;
FMP_CONTROLLER_STATE *FmpControllerState;
BOOLEAN Update;
FmpControllerState = GetFmpControllerState (Private);
if (FmpControllerState == NULL) {
//
// Can not update value if FMP Controller State does not exist.
// This variable is guaranteed to be created by GenerateFmpVariableNames().
//
return;
}
Update = FALSE;
if (!FmpControllerState->LastAttemptVersionValid) {
Update = TRUE;
}
if (FmpControllerState->LastAttemptVersion != LastAttemptVersion) {
Update = TRUE;
}
if (!Update) {
DEBUG ((DEBUG_INFO, "FmpDxe(%s): No need to update controller state. Same value as before.\n", mImageIdName));
} else {
FmpControllerState->LastAttemptVersionValid = TRUE;
FmpControllerState->LastAttemptVersion = LastAttemptVersion;
Status = gRT->SetVariable (
Private->FmpStateVariableName,
&gEfiCallerIdGuid,
EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,
sizeof (*FmpControllerState),
FmpControllerState
);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to update controller state. Status = %r\n", mImageIdName, Status));
} else {
DEBUG ((
DEBUG_INFO,
"FmpDxe(%s): Set variable %g %s LastAttemptVersion %08x\n",
mImageIdName,
&gEfiCallerIdGuid,
Private->FmpStateVariableName,
LastAttemptVersion
));
}
}
FreePool (FmpControllerState);
}
/**
Attempts to lock a single UEFI Variable propagating the error state of the
first lock attempt that fails. Uses gEfiCallerIdGuid as the variable GUID.
@param[in] PreviousStatus The previous UEFI Variable lock attempt status.
@param[in] VariableLock The EDK II Variable Lock Protocol instance.
@param[in] VariableName The name of the UEFI Variable to lock.
@retval EFI_SUCCESS The UEFI Variable was locked and the previous variable
lock attempt also succeeded.
@retval Other The UEFI Variable could not be locked or the previous
variable lock attempt failed.
**/
static
EFI_STATUS
LockFmpVariable (
IN EFI_STATUS PreviousStatus,
IN EDKII_VARIABLE_POLICY_PROTOCOL *VariablePolicy,
IN CHAR16 *VariableName
)
{
EFI_STATUS Status;
// If success, go ahead and set the policies to protect the target variables.
Status = RegisterBasicVariablePolicy (
VariablePolicy,
&gEfiCallerIdGuid,
VariableName,
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
);
if (EFI_ERROR (Status)) {
DEBUG ((
DEBUG_ERROR,
"FmpDxe(%s): Failed to lock variable %g %s. Status = %r\n",
mImageIdName,
&gEfiCallerIdGuid,
VariableName,
Status
));
}
if (EFI_ERROR (PreviousStatus)) {
return PreviousStatus;
}
return Status;
}
/**
Locks all the UEFI Variables that use gEfiCallerIdGuid of the currently
executing module.
@param[in] Private Private context structure for the managed controller.
@retval EFI_SUCCESS All UEFI variables are locked.
@retval EFI_UNSUPPORTED Variable Lock Protocol not found.
@retval Other One of the UEFI variables could not be locked.
**/
EFI_STATUS
LockAllFmpVariables (
FIRMWARE_MANAGEMENT_PRIVATE_DATA *Private
)
{
EFI_STATUS Status;
EDKII_VARIABLE_POLICY_PROTOCOL *VariablePolicy;
// Locate the VariablePolicy protocol.
Status = gBS->LocateProtocol (&gEdkiiVariablePolicyProtocolGuid, NULL, (VOID **)&VariablePolicy);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "FmpDxe %a - Could not locate VariablePolicy protocol! %r\n", __func__, Status));
return Status;
}
Status = EFI_SUCCESS;
Status = LockFmpVariable (Status, VariablePolicy, Private->VersionVariableName);
Status = LockFmpVariable (Status, VariablePolicy, Private->LsvVariableName);
Status = LockFmpVariable (Status, VariablePolicy, Private->LastAttemptStatusVariableName);
Status = LockFmpVariable (Status, VariablePolicy, Private->LastAttemptVersionVariableName);
Status = LockFmpVariable (Status, VariablePolicy, Private->FmpStateVariableName);
return Status;
}