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|
/** @file
The sample implementation for SMM variable protocol. And this driver
implements an SMI handler to communicate with the DXE runtime driver
to provide variable services.
Caution: This module requires additional review when modified.
This driver will have external input - variable data and communicate buffer in SMM mode.
This external input must be validated carefully to avoid security issue like
buffer overflow, integer overflow.
SmmVariableHandler() will receive untrusted input and do basic validation.
Each sub function VariableServiceGetVariable(), VariableServiceGetNextVariableName(),
VariableServiceSetVariable(), VariableServiceQueryVariableInfo(), ReclaimForOS(),
SmmVariableGetStatistics() should also do validation based on its own knowledge.
Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Protocol/SmmVariable.h>
#include <Protocol/SmmFirmwareVolumeBlock.h>
#include <Protocol/SmmFaultTolerantWrite.h>
#include <Protocol/MmEndOfDxe.h>
#include <Protocol/SmmVarCheck.h>
#include <Library/MmServicesTableLib.h>
#include <Guid/SmmVariableCommon.h>
#include "Variable.h"
BOOLEAN mAtRuntime = FALSE;
UINT8 *mVariableBufferPayload = NULL;
UINTN mVariableBufferPayloadSize;
/**
SecureBoot Hook for SetVariable.
@param[in] VariableName Name of Variable to be found.
@param[in] VendorGuid Variable vendor GUID.
**/
VOID
EFIAPI
SecureBootHook (
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid
)
{
return ;
}
/**
This code sets variable in storage blocks (Volatile or Non-Volatile).
@param VariableName Name of Variable to be found.
@param VendorGuid Variable vendor GUID.
@param Attributes Attribute value of the variable found
@param DataSize Size of Data found. If size is less than the
data, this value contains the required size.
@param Data Data pointer.
@return EFI_INVALID_PARAMETER Invalid parameter.
@return EFI_SUCCESS Set successfully.
@return EFI_OUT_OF_RESOURCES Resource not enough to set variable.
@return EFI_NOT_FOUND Not found.
@return EFI_WRITE_PROTECTED Variable is read-only.
**/
EFI_STATUS
EFIAPI
SmmVariableSetVariable (
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid,
IN UINT32 Attributes,
IN UINTN DataSize,
IN VOID *Data
)
{
EFI_STATUS Status;
//
// Disable write protection when the calling SetVariable() through EFI_SMM_VARIABLE_PROTOCOL.
//
mRequestSource = VarCheckFromTrusted;
Status = VariableServiceSetVariable (
VariableName,
VendorGuid,
Attributes,
DataSize,
Data
);
mRequestSource = VarCheckFromUntrusted;
return Status;
}
EFI_SMM_VARIABLE_PROTOCOL gSmmVariable = {
VariableServiceGetVariable,
VariableServiceGetNextVariableName,
SmmVariableSetVariable,
VariableServiceQueryVariableInfo
};
EDKII_SMM_VAR_CHECK_PROTOCOL mSmmVarCheck = { VarCheckRegisterSetVariableCheckHandler,
VarCheckVariablePropertySet,
VarCheckVariablePropertyGet };
/**
Return TRUE if ExitBootServices () has been called.
@retval TRUE If ExitBootServices () has been called.
**/
BOOLEAN
AtRuntime (
VOID
)
{
return mAtRuntime;
}
/**
Initializes a basic mutual exclusion lock.
This function initializes a basic mutual exclusion lock to the released state
and returns the lock. Each lock provides mutual exclusion access at its task
priority level. Since there is no preemption or multiprocessor support in EFI,
acquiring the lock only consists of raising to the locks TPL.
If Lock is NULL, then ASSERT().
If Priority is not a valid TPL value, then ASSERT().
@param Lock A pointer to the lock data structure to initialize.
@param Priority EFI TPL is associated with the lock.
@return The lock.
**/
EFI_LOCK *
InitializeLock (
IN OUT EFI_LOCK *Lock,
IN EFI_TPL Priority
)
{
return Lock;
}
/**
Acquires lock only at boot time. Simply returns at runtime.
This is a temperary function that will be removed when
EfiAcquireLock() in UefiLib can handle the call in UEFI
Runtimer driver in RT phase.
It calls EfiAcquireLock() at boot time, and simply returns
at runtime.
@param Lock A pointer to the lock to acquire.
**/
VOID
AcquireLockOnlyAtBootTime (
IN EFI_LOCK *Lock
)
{
}
/**
Releases lock only at boot time. Simply returns at runtime.
This is a temperary function which will be removed when
EfiReleaseLock() in UefiLib can handle the call in UEFI
Runtimer driver in RT phase.
It calls EfiReleaseLock() at boot time and simply returns
at runtime.
@param Lock A pointer to the lock to release.
**/
VOID
ReleaseLockOnlyAtBootTime (
IN EFI_LOCK *Lock
)
{
}
/**
Retrieve the SMM Fault Tolerent Write protocol interface.
@param[out] FtwProtocol The interface of SMM Ftw protocol
@retval EFI_SUCCESS The SMM FTW protocol instance was found and returned in FtwProtocol.
@retval EFI_NOT_FOUND The SMM FTW protocol instance was not found.
@retval EFI_INVALID_PARAMETER SarProtocol is NULL.
**/
EFI_STATUS
GetFtwProtocol (
OUT VOID **FtwProtocol
)
{
EFI_STATUS Status;
//
// Locate Smm Fault Tolerent Write protocol
//
Status = gMmst->MmLocateProtocol (
&gEfiSmmFaultTolerantWriteProtocolGuid,
NULL,
FtwProtocol
);
return Status;
}
/**
Retrieve the SMM FVB protocol interface by HANDLE.
@param[in] FvBlockHandle The handle of SMM FVB protocol that provides services for
reading, writing, and erasing the target block.
@param[out] FvBlock The interface of SMM FVB protocol
@retval EFI_SUCCESS The interface information for the specified protocol was returned.
@retval EFI_UNSUPPORTED The device does not support the SMM FVB protocol.
@retval EFI_INVALID_PARAMETER FvBlockHandle is not a valid EFI_HANDLE or FvBlock is NULL.
**/
EFI_STATUS
GetFvbByHandle (
IN EFI_HANDLE FvBlockHandle,
OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL **FvBlock
)
{
//
// To get the SMM FVB protocol interface on the handle
//
return gMmst->MmHandleProtocol (
FvBlockHandle,
&gEfiSmmFirmwareVolumeBlockProtocolGuid,
(VOID **) FvBlock
);
}
/**
Function returns an array of handles that support the SMM FVB protocol
in a buffer allocated from pool.
@param[out] NumberHandles The number of handles returned in Buffer.
@param[out] Buffer A pointer to the buffer to return the requested
array of handles that support SMM FVB protocol.
@retval EFI_SUCCESS The array of handles was returned in Buffer, and the number of
handles in Buffer was returned in NumberHandles.
@retval EFI_NOT_FOUND No SMM FVB handle was found.
@retval EFI_OUT_OF_RESOURCES There is not enough pool memory to store the matching results.
@retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
**/
EFI_STATUS
GetFvbCountAndBuffer (
OUT UINTN *NumberHandles,
OUT EFI_HANDLE **Buffer
)
{
EFI_STATUS Status;
UINTN BufferSize;
if ((NumberHandles == NULL) || (Buffer == NULL)) {
return EFI_INVALID_PARAMETER;
}
BufferSize = 0;
*NumberHandles = 0;
*Buffer = NULL;
Status = gMmst->MmLocateHandle (
ByProtocol,
&gEfiSmmFirmwareVolumeBlockProtocolGuid,
NULL,
&BufferSize,
*Buffer
);
if (EFI_ERROR(Status) && Status != EFI_BUFFER_TOO_SMALL) {
return EFI_NOT_FOUND;
}
*Buffer = AllocatePool (BufferSize);
if (*Buffer == NULL) {
return EFI_OUT_OF_RESOURCES;
}
Status = gMmst->MmLocateHandle (
ByProtocol,
&gEfiSmmFirmwareVolumeBlockProtocolGuid,
NULL,
&BufferSize,
*Buffer
);
*NumberHandles = BufferSize / sizeof(EFI_HANDLE);
if (EFI_ERROR(Status)) {
*NumberHandles = 0;
FreePool (*Buffer);
*Buffer = NULL;
}
return Status;
}
/**
Get the variable statistics information from the information buffer pointed by gVariableInfo.
Caution: This function may be invoked at SMM runtime.
InfoEntry and InfoSize are external input. Care must be taken to make sure not security issue at runtime.
@param[in, out] InfoEntry A pointer to the buffer of variable information entry.
On input, point to the variable information returned last time. if
InfoEntry->VendorGuid is zero, return the first information.
On output, point to the next variable information.
@param[in, out] InfoSize On input, the size of the variable information buffer.
On output, the returned variable information size.
@retval EFI_SUCCESS The variable information is found and returned successfully.
@retval EFI_UNSUPPORTED No variable inoformation exists in variable driver. The
PcdVariableCollectStatistics should be set TRUE to support it.
@retval EFI_BUFFER_TOO_SMALL The buffer is too small to hold the next variable information.
@retval EFI_INVALID_PARAMETER Input parameter is invalid.
**/
EFI_STATUS
SmmVariableGetStatistics (
IN OUT VARIABLE_INFO_ENTRY *InfoEntry,
IN OUT UINTN *InfoSize
)
{
VARIABLE_INFO_ENTRY *VariableInfo;
UINTN NameSize;
UINTN StatisticsInfoSize;
CHAR16 *InfoName;
UINTN InfoNameMaxSize;
EFI_GUID VendorGuid;
if (InfoEntry == NULL) {
return EFI_INVALID_PARAMETER;
}
VariableInfo = gVariableInfo;
if (VariableInfo == NULL) {
return EFI_UNSUPPORTED;
}
StatisticsInfoSize = sizeof (VARIABLE_INFO_ENTRY);
if (*InfoSize < StatisticsInfoSize) {
*InfoSize = StatisticsInfoSize;
return EFI_BUFFER_TOO_SMALL;
}
InfoName = (CHAR16 *)(InfoEntry + 1);
InfoNameMaxSize = (*InfoSize - sizeof (VARIABLE_INFO_ENTRY));
CopyGuid (&VendorGuid, &InfoEntry->VendorGuid);
if (IsZeroGuid (&VendorGuid)) {
//
// Return the first variable info
//
NameSize = StrSize (VariableInfo->Name);
StatisticsInfoSize = sizeof (VARIABLE_INFO_ENTRY) + NameSize;
if (*InfoSize < StatisticsInfoSize) {
*InfoSize = StatisticsInfoSize;
return EFI_BUFFER_TOO_SMALL;
}
CopyMem (InfoEntry, VariableInfo, sizeof (VARIABLE_INFO_ENTRY));
CopyMem (InfoName, VariableInfo->Name, NameSize);
*InfoSize = StatisticsInfoSize;
return EFI_SUCCESS;
}
//
// Get the next variable info
//
while (VariableInfo != NULL) {
if (CompareGuid (&VariableInfo->VendorGuid, &VendorGuid)) {
NameSize = StrSize (VariableInfo->Name);
if (NameSize <= InfoNameMaxSize) {
if (CompareMem (VariableInfo->Name, InfoName, NameSize) == 0) {
//
// Find the match one
//
VariableInfo = VariableInfo->Next;
break;
}
}
}
VariableInfo = VariableInfo->Next;
};
if (VariableInfo == NULL) {
*InfoSize = 0;
return EFI_SUCCESS;
}
//
// Output the new variable info
//
NameSize = StrSize (VariableInfo->Name);
StatisticsInfoSize = sizeof (VARIABLE_INFO_ENTRY) + NameSize;
if (*InfoSize < StatisticsInfoSize) {
*InfoSize = StatisticsInfoSize;
return EFI_BUFFER_TOO_SMALL;
}
CopyMem (InfoEntry, VariableInfo, sizeof (VARIABLE_INFO_ENTRY));
CopyMem (InfoName, VariableInfo->Name, NameSize);
*InfoSize = StatisticsInfoSize;
return EFI_SUCCESS;
}
/**
Communication service SMI Handler entry.
This SMI handler provides services for the variable wrapper driver.
Caution: This function may receive untrusted input.
This variable data and communicate buffer are external input, so this function will do basic validation.
Each sub function VariableServiceGetVariable(), VariableServiceGetNextVariableName(),
VariableServiceSetVariable(), VariableServiceQueryVariableInfo(), ReclaimForOS(),
SmmVariableGetStatistics() should also do validation based on its own knowledge.
@param[in] DispatchHandle The unique handle assigned to this handler by SmiHandlerRegister().
@param[in] RegisterContext Points to an optional handler context which was specified when the
handler was registered.
@param[in, out] CommBuffer A pointer to a collection of data in memory that will
be conveyed from a non-SMM environment into an SMM environment.
@param[in, out] CommBufferSize The size of the CommBuffer.
@retval EFI_SUCCESS The interrupt was handled and quiesced. No other handlers
should still be called.
@retval EFI_WARN_INTERRUPT_SOURCE_QUIESCED The interrupt has been quiesced but other handlers should
still be called.
@retval EFI_WARN_INTERRUPT_SOURCE_PENDING The interrupt is still pending and other handlers should still
be called.
@retval EFI_INTERRUPT_PENDING The interrupt could not be quiesced.
**/
EFI_STATUS
EFIAPI
SmmVariableHandler (
IN EFI_HANDLE DispatchHandle,
IN CONST VOID *RegisterContext,
IN OUT VOID *CommBuffer,
IN OUT UINTN *CommBufferSize
)
{
EFI_STATUS Status;
SMM_VARIABLE_COMMUNICATE_HEADER *SmmVariableFunctionHeader;
SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE *SmmVariableHeader;
SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME *GetNextVariableName;
SMM_VARIABLE_COMMUNICATE_QUERY_VARIABLE_INFO *QueryVariableInfo;
SMM_VARIABLE_COMMUNICATE_GET_PAYLOAD_SIZE *GetPayloadSize;
VARIABLE_INFO_ENTRY *VariableInfo;
SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE *VariableToLock;
SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY *CommVariableProperty;
UINTN InfoSize;
UINTN NameBufferSize;
UINTN CommBufferPayloadSize;
UINTN TempCommBufferSize;
//
// If input is invalid, stop processing this SMI
//
if (CommBuffer == NULL || CommBufferSize == NULL) {
return EFI_SUCCESS;
}
TempCommBufferSize = *CommBufferSize;
if (TempCommBufferSize < SMM_VARIABLE_COMMUNICATE_HEADER_SIZE) {
DEBUG ((EFI_D_ERROR, "SmmVariableHandler: SMM communication buffer size invalid!\n"));
return EFI_SUCCESS;
}
CommBufferPayloadSize = TempCommBufferSize - SMM_VARIABLE_COMMUNICATE_HEADER_SIZE;
if (CommBufferPayloadSize > mVariableBufferPayloadSize) {
DEBUG ((EFI_D_ERROR, "SmmVariableHandler: SMM communication buffer payload size invalid!\n"));
return EFI_SUCCESS;
}
if (!VariableSmmIsBufferOutsideSmmValid ((UINTN)CommBuffer, TempCommBufferSize)) {
DEBUG ((EFI_D_ERROR, "SmmVariableHandler: SMM communication buffer in SMRAM or overflow!\n"));
return EFI_SUCCESS;
}
SmmVariableFunctionHeader = (SMM_VARIABLE_COMMUNICATE_HEADER *)CommBuffer;
switch (SmmVariableFunctionHeader->Function) {
case SMM_VARIABLE_FUNCTION_GET_VARIABLE:
if (CommBufferPayloadSize < OFFSET_OF(SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name)) {
DEBUG ((EFI_D_ERROR, "GetVariable: SMM communication buffer size invalid!\n"));
return EFI_SUCCESS;
}
//
// Copy the input communicate buffer payload to pre-allocated SMM variable buffer payload.
//
CopyMem (mVariableBufferPayload, SmmVariableFunctionHeader->Data, CommBufferPayloadSize);
SmmVariableHeader = (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE *) mVariableBufferPayload;
if (((UINTN)(~0) - SmmVariableHeader->DataSize < OFFSET_OF(SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name)) ||
((UINTN)(~0) - SmmVariableHeader->NameSize < OFFSET_OF(SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name) + SmmVariableHeader->DataSize)) {
//
// Prevent InfoSize overflow happen
//
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
InfoSize = OFFSET_OF(SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name)
+ SmmVariableHeader->DataSize + SmmVariableHeader->NameSize;
//
// SMRAM range check already covered before
//
if (InfoSize > CommBufferPayloadSize) {
DEBUG ((EFI_D_ERROR, "GetVariable: Data size exceed communication buffer size limit!\n"));
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
//
// The VariableSpeculationBarrier() call here is to ensure the previous
// range/content checks for the CommBuffer have been completed before the
// subsequent consumption of the CommBuffer content.
//
VariableSpeculationBarrier ();
if (SmmVariableHeader->NameSize < sizeof (CHAR16) || SmmVariableHeader->Name[SmmVariableHeader->NameSize/sizeof (CHAR16) - 1] != L'\0') {
//
// Make sure VariableName is A Null-terminated string.
//
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
Status = VariableServiceGetVariable (
SmmVariableHeader->Name,
&SmmVariableHeader->Guid,
&SmmVariableHeader->Attributes,
&SmmVariableHeader->DataSize,
(UINT8 *)SmmVariableHeader->Name + SmmVariableHeader->NameSize
);
CopyMem (SmmVariableFunctionHeader->Data, mVariableBufferPayload, CommBufferPayloadSize);
break;
case SMM_VARIABLE_FUNCTION_GET_NEXT_VARIABLE_NAME:
if (CommBufferPayloadSize < OFFSET_OF(SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME, Name)) {
DEBUG ((EFI_D_ERROR, "GetNextVariableName: SMM communication buffer size invalid!\n"));
return EFI_SUCCESS;
}
//
// Copy the input communicate buffer payload to pre-allocated SMM variable buffer payload.
//
CopyMem (mVariableBufferPayload, SmmVariableFunctionHeader->Data, CommBufferPayloadSize);
GetNextVariableName = (SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME *) mVariableBufferPayload;
if ((UINTN)(~0) - GetNextVariableName->NameSize < OFFSET_OF(SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME, Name)) {
//
// Prevent InfoSize overflow happen
//
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
InfoSize = OFFSET_OF(SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME, Name) + GetNextVariableName->NameSize;
//
// SMRAM range check already covered before
//
if (InfoSize > CommBufferPayloadSize) {
DEBUG ((EFI_D_ERROR, "GetNextVariableName: Data size exceed communication buffer size limit!\n"));
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
NameBufferSize = CommBufferPayloadSize - OFFSET_OF(SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME, Name);
if (NameBufferSize < sizeof (CHAR16) || GetNextVariableName->Name[NameBufferSize/sizeof (CHAR16) - 1] != L'\0') {
//
// Make sure input VariableName is A Null-terminated string.
//
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
Status = VariableServiceGetNextVariableName (
&GetNextVariableName->NameSize,
GetNextVariableName->Name,
&GetNextVariableName->Guid
);
CopyMem (SmmVariableFunctionHeader->Data, mVariableBufferPayload, CommBufferPayloadSize);
break;
case SMM_VARIABLE_FUNCTION_SET_VARIABLE:
if (CommBufferPayloadSize < OFFSET_OF(SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name)) {
DEBUG ((EFI_D_ERROR, "SetVariable: SMM communication buffer size invalid!\n"));
return EFI_SUCCESS;
}
//
// Copy the input communicate buffer payload to pre-allocated SMM variable buffer payload.
//
CopyMem (mVariableBufferPayload, SmmVariableFunctionHeader->Data, CommBufferPayloadSize);
SmmVariableHeader = (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE *) mVariableBufferPayload;
if (((UINTN)(~0) - SmmVariableHeader->DataSize < OFFSET_OF(SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name)) ||
((UINTN)(~0) - SmmVariableHeader->NameSize < OFFSET_OF(SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name) + SmmVariableHeader->DataSize)) {
//
// Prevent InfoSize overflow happen
//
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
InfoSize = OFFSET_OF(SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name)
+ SmmVariableHeader->DataSize + SmmVariableHeader->NameSize;
//
// SMRAM range check already covered before
// Data buffer should not contain SMM range
//
if (InfoSize > CommBufferPayloadSize) {
DEBUG ((EFI_D_ERROR, "SetVariable: Data size exceed communication buffer size limit!\n"));
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
//
// The VariableSpeculationBarrier() call here is to ensure the previous
// range/content checks for the CommBuffer have been completed before the
// subsequent consumption of the CommBuffer content.
//
VariableSpeculationBarrier ();
if (SmmVariableHeader->NameSize < sizeof (CHAR16) || SmmVariableHeader->Name[SmmVariableHeader->NameSize/sizeof (CHAR16) - 1] != L'\0') {
//
// Make sure VariableName is A Null-terminated string.
//
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
Status = VariableServiceSetVariable (
SmmVariableHeader->Name,
&SmmVariableHeader->Guid,
SmmVariableHeader->Attributes,
SmmVariableHeader->DataSize,
(UINT8 *)SmmVariableHeader->Name + SmmVariableHeader->NameSize
);
break;
case SMM_VARIABLE_FUNCTION_QUERY_VARIABLE_INFO:
if (CommBufferPayloadSize < sizeof (SMM_VARIABLE_COMMUNICATE_QUERY_VARIABLE_INFO)) {
DEBUG ((EFI_D_ERROR, "QueryVariableInfo: SMM communication buffer size invalid!\n"));
return EFI_SUCCESS;
}
QueryVariableInfo = (SMM_VARIABLE_COMMUNICATE_QUERY_VARIABLE_INFO *) SmmVariableFunctionHeader->Data;
Status = VariableServiceQueryVariableInfo (
QueryVariableInfo->Attributes,
&QueryVariableInfo->MaximumVariableStorageSize,
&QueryVariableInfo->RemainingVariableStorageSize,
&QueryVariableInfo->MaximumVariableSize
);
break;
case SMM_VARIABLE_FUNCTION_GET_PAYLOAD_SIZE:
if (CommBufferPayloadSize < sizeof (SMM_VARIABLE_COMMUNICATE_GET_PAYLOAD_SIZE)) {
DEBUG ((EFI_D_ERROR, "GetPayloadSize: SMM communication buffer size invalid!\n"));
return EFI_SUCCESS;
}
GetPayloadSize = (SMM_VARIABLE_COMMUNICATE_GET_PAYLOAD_SIZE *) SmmVariableFunctionHeader->Data;
GetPayloadSize->VariablePayloadSize = mVariableBufferPayloadSize;
Status = EFI_SUCCESS;
break;
case SMM_VARIABLE_FUNCTION_READY_TO_BOOT:
if (AtRuntime()) {
Status = EFI_UNSUPPORTED;
break;
}
if (!mEndOfDxe) {
MorLockInitAtEndOfDxe ();
mEndOfDxe = TRUE;
VarCheckLibInitializeAtEndOfDxe (NULL);
//
// The initialization for variable quota.
//
InitializeVariableQuota ();
}
ReclaimForOS ();
Status = EFI_SUCCESS;
break;
case SMM_VARIABLE_FUNCTION_EXIT_BOOT_SERVICE:
mAtRuntime = TRUE;
Status = EFI_SUCCESS;
break;
case SMM_VARIABLE_FUNCTION_GET_STATISTICS:
VariableInfo = (VARIABLE_INFO_ENTRY *) SmmVariableFunctionHeader->Data;
InfoSize = TempCommBufferSize - SMM_VARIABLE_COMMUNICATE_HEADER_SIZE;
//
// Do not need to check SmmVariableFunctionHeader->Data in SMRAM here.
// It is covered by previous CommBuffer check
//
//
// Do not need to check CommBufferSize buffer as it should point to SMRAM
// that was used by SMM core to cache CommSize from SmmCommunication protocol.
//
Status = SmmVariableGetStatistics (VariableInfo, &InfoSize);
*CommBufferSize = InfoSize + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE;
break;
case SMM_VARIABLE_FUNCTION_LOCK_VARIABLE:
if (mEndOfDxe) {
Status = EFI_ACCESS_DENIED;
} else {
VariableToLock = (SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE *) SmmVariableFunctionHeader->Data;
Status = VariableLockRequestToLock (
NULL,
VariableToLock->Name,
&VariableToLock->Guid
);
}
break;
case SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_SET:
if (mEndOfDxe) {
Status = EFI_ACCESS_DENIED;
} else {
CommVariableProperty = (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY *) SmmVariableFunctionHeader->Data;
Status = VarCheckVariablePropertySet (
CommVariableProperty->Name,
&CommVariableProperty->Guid,
&CommVariableProperty->VariableProperty
);
}
break;
case SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_GET:
if (CommBufferPayloadSize < OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name)) {
DEBUG ((EFI_D_ERROR, "VarCheckVariablePropertyGet: SMM communication buffer size invalid!\n"));
return EFI_SUCCESS;
}
//
// Copy the input communicate buffer payload to pre-allocated SMM variable buffer payload.
//
CopyMem (mVariableBufferPayload, SmmVariableFunctionHeader->Data, CommBufferPayloadSize);
CommVariableProperty = (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY *) mVariableBufferPayload;
if ((UINTN) (~0) - CommVariableProperty->NameSize < OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name)) {
//
// Prevent InfoSize overflow happen
//
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
InfoSize = OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name) + CommVariableProperty->NameSize;
//
// SMRAM range check already covered before
//
if (InfoSize > CommBufferPayloadSize) {
DEBUG ((EFI_D_ERROR, "VarCheckVariablePropertyGet: Data size exceed communication buffer size limit!\n"));
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
//
// The VariableSpeculationBarrier() call here is to ensure the previous
// range/content checks for the CommBuffer have been completed before the
// subsequent consumption of the CommBuffer content.
//
VariableSpeculationBarrier ();
if (CommVariableProperty->NameSize < sizeof (CHAR16) || CommVariableProperty->Name[CommVariableProperty->NameSize/sizeof (CHAR16) - 1] != L'\0') {
//
// Make sure VariableName is A Null-terminated string.
//
Status = EFI_ACCESS_DENIED;
goto EXIT;
}
Status = VarCheckVariablePropertyGet (
CommVariableProperty->Name,
&CommVariableProperty->Guid,
&CommVariableProperty->VariableProperty
);
CopyMem (SmmVariableFunctionHeader->Data, mVariableBufferPayload, CommBufferPayloadSize);
break;
default:
Status = EFI_UNSUPPORTED;
}
EXIT:
SmmVariableFunctionHeader->ReturnStatus = Status;
return EFI_SUCCESS;
}
/**
SMM END_OF_DXE protocol notification event handler.
@param Protocol Points to the protocol's unique identifier
@param Interface Points to the interface instance
@param Handle The handle on which the interface was installed
@retval EFI_SUCCESS SmmEndOfDxeCallback runs successfully
**/
EFI_STATUS
EFIAPI
SmmEndOfDxeCallback (
IN CONST EFI_GUID *Protocol,
IN VOID *Interface,
IN EFI_HANDLE Handle
)
{
DEBUG ((EFI_D_INFO, "[Variable]SMM_END_OF_DXE is signaled\n"));
MorLockInitAtEndOfDxe ();
mEndOfDxe = TRUE;
VarCheckLibInitializeAtEndOfDxe (NULL);
//
// The initialization for variable quota.
//
InitializeVariableQuota ();
if (PcdGetBool (PcdReclaimVariableSpaceAtEndOfDxe)) {
ReclaimForOS ();
}
return EFI_SUCCESS;
}
/**
Initializes variable write service for SMM.
**/
VOID
VariableWriteServiceInitializeSmm (
VOID
)
{
EFI_STATUS Status;
Status = VariableWriteServiceInitialize ();
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "Variable write service initialization failed. Status = %r\n", Status));
}
//
// Notify the variable wrapper driver the variable write service is ready
//
VariableNotifySmmWriteReady ();
}
/**
SMM Fault Tolerant Write protocol notification event handler.
Non-Volatile variable write may needs FTW protocol to reclaim when
writting variable.
@param Protocol Points to the protocol's unique identifier
@param Interface Points to the interface instance
@param Handle The handle on which the interface was installed
@retval EFI_SUCCESS SmmEventCallback runs successfully
@retval EFI_NOT_FOUND The Fvb protocol for variable is not found.
**/
EFI_STATUS
EFIAPI
SmmFtwNotificationEvent (
IN CONST EFI_GUID *Protocol,
IN VOID *Interface,
IN EFI_HANDLE Handle
)
{
EFI_STATUS Status;
EFI_PHYSICAL_ADDRESS VariableStoreBase;
EFI_SMM_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvbProtocol;
EFI_SMM_FAULT_TOLERANT_WRITE_PROTOCOL *FtwProtocol;
EFI_PHYSICAL_ADDRESS NvStorageVariableBase;
UINTN FtwMaxBlockSize;
if (mVariableModuleGlobal->FvbInstance != NULL) {
return EFI_SUCCESS;
}
//
// Ensure SMM FTW protocol is installed.
//
Status = GetFtwProtocol ((VOID **)&FtwProtocol);
if (EFI_ERROR (Status)) {
return Status;
}
Status = FtwProtocol->GetMaxBlockSize (FtwProtocol, &FtwMaxBlockSize);
if (!EFI_ERROR (Status)) {
ASSERT (PcdGet32 (PcdFlashNvStorageVariableSize) <= FtwMaxBlockSize);
}
NvStorageVariableBase = NV_STORAGE_VARIABLE_BASE;
VariableStoreBase = NvStorageVariableBase + mNvFvHeaderCache->HeaderLength;
//
// Let NonVolatileVariableBase point to flash variable store base directly after FTW ready.
//
mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase = VariableStoreBase;
//
// Find the proper FVB protocol for variable.
//
Status = GetFvbInfoByAddress (NvStorageVariableBase, NULL, &FvbProtocol);
if (EFI_ERROR (Status)) {
return EFI_NOT_FOUND;
}
mVariableModuleGlobal->FvbInstance = FvbProtocol;
//
// Initializes variable write service after FTW was ready.
//
VariableWriteServiceInitializeSmm ();
return EFI_SUCCESS;
}
/**
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.
@retval EFI_SUCCESS Variable service successfully initialized.
**/
EFI_STATUS
EFIAPI
MmVariableServiceInitialize (
VOID
)
{
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 = gMmst->MmInstallProtocolInterface (
&VariableHandle,
&gEfiSmmVariableProtocolGuid,
EFI_NATIVE_INTERFACE,
&gSmmVariable
);
ASSERT_EFI_ERROR (Status);
Status = gMmst->MmInstallProtocolInterface (
&VariableHandle,
&gEdkiiSmmVarCheckProtocolGuid,
EFI_NATIVE_INTERFACE,
&mSmmVarCheck
);
ASSERT_EFI_ERROR (Status);
mVariableBufferPayloadSize = GetMaxVariableSize () +
OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name) - GetVariableHeaderSize ();
Status = gMmst->MmAllocatePool (
EfiRuntimeServicesData,
mVariableBufferPayloadSize,
(VOID **)&mVariableBufferPayload
);
ASSERT_EFI_ERROR (Status);
///
/// Register SMM variable SMI handler
///
VariableHandle = NULL;
Status = gMmst->MmiHandlerRegister (SmmVariableHandler, &gEfiSmmVariableProtocolGuid, &VariableHandle);
ASSERT_EFI_ERROR (Status);
//
// Notify the variable wrapper driver the variable service is ready
//
VariableNotifySmmReady ();
//
// Register EFI_SMM_END_OF_DXE_PROTOCOL_GUID notify function.
//
Status = gMmst->MmRegisterProtocolNotify (
&gEfiMmEndOfDxeProtocolGuid,
SmmEndOfDxeCallback,
&SmmEndOfDxeRegistration
);
ASSERT_EFI_ERROR (Status);
if (!PcdGetBool (PcdEmuVariableNvModeEnable)) {
//
// Register FtwNotificationEvent () notify function.
//
Status = gMmst->MmRegisterProtocolNotify (
&gEfiSmmFaultTolerantWriteProtocolGuid,
SmmFtwNotificationEvent,
&SmmFtwRegistration
);
ASSERT_EFI_ERROR (Status);
SmmFtwNotificationEvent (NULL, NULL, NULL);
} else {
//
// Emulated non-volatile variable mode does not depend on FVB and FTW.
//
VariableWriteServiceInitializeSmm ();
}
return EFI_SUCCESS;
}
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