/** @file
Implement all four UEFI Runtime Variable services for the nonvolatile
and volatile storage space and install variable architecture protocol
based on SMM variable module.
Caution: This module requires additional review when modified.
This driver will have external input - variable data.
This external input must be validated carefully to avoid security issue like
buffer overflow, integer overflow.
RuntimeServiceGetVariable() and RuntimeServiceSetVariable() are external API
to receive data buffer. The size should be checked carefully.
InitCommunicateBuffer() is really function to check the variable data size.
Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.
Copyright (c) Microsoft Corporation.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include "PrivilegePolymorphic.h"
#include "VariableParsing.h"
EFI_HANDLE mHandle = NULL;
EFI_SMM_VARIABLE_PROTOCOL *mSmmVariable = NULL;
EFI_EVENT mVirtualAddressChangeEvent = NULL;
EFI_MM_COMMUNICATION2_PROTOCOL *mMmCommunication2 = NULL;
UINT8 *mVariableBuffer = NULL;
UINT8 *mVariableBufferPhysical = NULL;
VARIABLE_INFO_ENTRY *mVariableInfo = NULL;
VARIABLE_STORE_HEADER *mVariableRuntimeHobCacheBuffer = NULL;
VARIABLE_STORE_HEADER *mVariableRuntimeNvCacheBuffer = NULL;
VARIABLE_STORE_HEADER *mVariableRuntimeVolatileCacheBuffer = NULL;
UINTN mVariableBufferSize;
UINTN mVariableRuntimeHobCacheBufferSize;
UINTN mVariableRuntimeNvCacheBufferSize;
UINTN mVariableRuntimeVolatileCacheBufferSize;
UINTN mVariableBufferPayloadSize;
BOOLEAN mVariableRuntimeCachePendingUpdate;
BOOLEAN mVariableRuntimeCacheReadLock;
BOOLEAN mVariableAuthFormat;
BOOLEAN mHobFlushComplete;
EFI_LOCK mVariableServicesLock;
EDKII_VARIABLE_LOCK_PROTOCOL mVariableLock;
EDKII_VAR_CHECK_PROTOCOL mVarCheck;
/**
The logic to initialize the VariablePolicy engine is in its own file.
**/
EFI_STATUS
EFIAPI
VariablePolicySmmDxeMain (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
);
/**
Some Secure Boot Policy Variable may update following other variable changes(SecureBoot follows PK change, etc).
Record their initial State when variable write service is ready.
**/
VOID
EFIAPI
RecordSecureBootPolicyVarData(
VOID
);
/**
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
)
{
if (!EfiAtRuntime ()) {
EfiAcquireLock (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
)
{
if (!EfiAtRuntime ()) {
EfiReleaseLock (Lock);
}
}
/**
Return TRUE if ExitBootServices () has been called.
@retval TRUE If ExitBootServices () has been called. FALSE if ExitBootServices () has not been called.
**/
BOOLEAN
AtRuntime (
VOID
)
{
return EfiAtRuntime ();
}
/**
Initialize the variable cache buffer as an empty variable store.
@param[out] VariableCacheBuffer A pointer to pointer of a cache variable store.
@param[in,out] TotalVariableCacheSize On input, the minimum size needed for the UEFI variable store cache
buffer that is allocated. On output, the actual size of the buffer allocated.
If TotalVariableCacheSize is zero, a buffer will not be allocated and the
function will return with EFI_SUCCESS.
@retval EFI_SUCCESS The variable cache was allocated and initialized successfully.
@retval EFI_INVALID_PARAMETER A given pointer is NULL or an invalid variable store size was specified.
@retval EFI_OUT_OF_RESOURCES Insufficient resources are available to allocate the variable store cache buffer.
**/
EFI_STATUS
InitVariableCache (
OUT VARIABLE_STORE_HEADER **VariableCacheBuffer,
IN OUT UINTN *TotalVariableCacheSize
)
{
VARIABLE_STORE_HEADER *VariableCacheStorePtr;
if (TotalVariableCacheSize == NULL) {
return EFI_INVALID_PARAMETER;
}
if (*TotalVariableCacheSize == 0) {
return EFI_SUCCESS;
}
if (VariableCacheBuffer == NULL || *TotalVariableCacheSize < sizeof (VARIABLE_STORE_HEADER)) {
return EFI_INVALID_PARAMETER;
}
*TotalVariableCacheSize = ALIGN_VALUE (*TotalVariableCacheSize, sizeof (UINT32));
//
// Allocate NV Storage Cache and initialize it to all 1's (like an erased FV)
//
*VariableCacheBuffer = (VARIABLE_STORE_HEADER *) AllocateRuntimePages (
EFI_SIZE_TO_PAGES (*TotalVariableCacheSize)
);
if (*VariableCacheBuffer == NULL) {
return EFI_OUT_OF_RESOURCES;
}
VariableCacheStorePtr = *VariableCacheBuffer;
SetMem32 ((VOID *) VariableCacheStorePtr, *TotalVariableCacheSize, (UINT32) 0xFFFFFFFF);
ZeroMem ((VOID *) VariableCacheStorePtr, sizeof (VARIABLE_STORE_HEADER));
VariableCacheStorePtr->Size = (UINT32) *TotalVariableCacheSize;
VariableCacheStorePtr->Format = VARIABLE_STORE_FORMATTED;
VariableCacheStorePtr->State = VARIABLE_STORE_HEALTHY;
return EFI_SUCCESS;
}
/**
Initialize the communicate buffer using DataSize and Function.
The communicate size is: SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE +
DataSize.
Caution: This function may receive untrusted input.
The data size external input, so this function will validate it carefully to avoid buffer overflow.
@param[out] DataPtr Points to the data in the communicate buffer.
@param[in] DataSize The data size to send to SMM.
@param[in] Function The function number to initialize the communicate header.
@retval EFI_INVALID_PARAMETER The data size is too big.
@retval EFI_SUCCESS Find the specified variable.
**/
EFI_STATUS
InitCommunicateBuffer (
OUT VOID **DataPtr OPTIONAL,
IN UINTN DataSize,
IN UINTN Function
)
{
EFI_MM_COMMUNICATE_HEADER *SmmCommunicateHeader;
SMM_VARIABLE_COMMUNICATE_HEADER *SmmVariableFunctionHeader;
if (DataSize + SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE > mVariableBufferSize) {
return EFI_INVALID_PARAMETER;
}
SmmCommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *) mVariableBuffer;
CopyGuid (&SmmCommunicateHeader->HeaderGuid, &gEfiSmmVariableProtocolGuid);
SmmCommunicateHeader->MessageLength = DataSize + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE;
SmmVariableFunctionHeader = (SMM_VARIABLE_COMMUNICATE_HEADER *) SmmCommunicateHeader->Data;
SmmVariableFunctionHeader->Function = Function;
if (DataPtr != NULL) {
*DataPtr = SmmVariableFunctionHeader->Data;
}
return EFI_SUCCESS;
}
/**
Send the data in communicate buffer to SMM.
@param[in] DataSize This size of the function header and the data.
@retval EFI_SUCCESS Success is returned from the functin in SMM.
@retval Others Failure is returned from the function in SMM.
**/
EFI_STATUS
SendCommunicateBuffer (
IN UINTN DataSize
)
{
EFI_STATUS Status;
UINTN CommSize;
EFI_MM_COMMUNICATE_HEADER *SmmCommunicateHeader;
SMM_VARIABLE_COMMUNICATE_HEADER *SmmVariableFunctionHeader;
CommSize = DataSize + SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE;
Status = mMmCommunication2->Communicate (mMmCommunication2,
mVariableBufferPhysical,
mVariableBuffer,
&CommSize);
ASSERT_EFI_ERROR (Status);
SmmCommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *) mVariableBuffer;
SmmVariableFunctionHeader = (SMM_VARIABLE_COMMUNICATE_HEADER *)SmmCommunicateHeader->Data;
return SmmVariableFunctionHeader->ReturnStatus;
}
/**
Mark a variable that will become read-only after leaving the DXE phase of execution.
@param[in] This The VARIABLE_LOCK_PROTOCOL instance.
@param[in] VariableName A pointer to the variable name that will be made read-only subsequently.
@param[in] VendorGuid A pointer to the vendor GUID that will be made read-only subsequently.
@retval EFI_SUCCESS The variable specified by the VariableName and the VendorGuid was marked
as pending to be read-only.
@retval EFI_INVALID_PARAMETER VariableName or VendorGuid is NULL.
Or VariableName is an empty string.
@retval EFI_ACCESS_DENIED EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
already been signaled.
@retval EFI_OUT_OF_RESOURCES There is not enough resource to hold the lock request.
**/
EFI_STATUS
EFIAPI
VariableLockRequestToLock (
IN CONST EDKII_VARIABLE_LOCK_PROTOCOL *This,
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid
)
{
EFI_STATUS Status;
UINTN VariableNameSize;
UINTN PayloadSize;
SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE *VariableToLock;
if (VariableName == NULL || VariableName[0] == 0 || VendorGuid == NULL) {
return EFI_INVALID_PARAMETER;
}
VariableNameSize = StrSize (VariableName);
VariableToLock = NULL;
//
// If VariableName exceeds SMM payload limit. Return failure
//
if (VariableNameSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE, Name)) {
return EFI_INVALID_PARAMETER;
}
AcquireLockOnlyAtBootTime(&mVariableServicesLock);
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + PayloadSize.
//
PayloadSize = OFFSET_OF (SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE, Name) + VariableNameSize;
Status = InitCommunicateBuffer ((VOID **) &VariableToLock, PayloadSize, SMM_VARIABLE_FUNCTION_LOCK_VARIABLE);
if (EFI_ERROR (Status)) {
goto Done;
}
ASSERT (VariableToLock != NULL);
CopyGuid (&VariableToLock->Guid, VendorGuid);
VariableToLock->NameSize = VariableNameSize;
CopyMem (VariableToLock->Name, VariableName, VariableToLock->NameSize);
//
// Send data to SMM.
//
Status = SendCommunicateBuffer (PayloadSize);
Done:
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
Register SetVariable check handler.
@param[in] Handler Pointer to check handler.
@retval EFI_SUCCESS The SetVariable check handler was registered successfully.
@retval EFI_INVALID_PARAMETER Handler is NULL.
@retval EFI_ACCESS_DENIED EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
already been signaled.
@retval EFI_OUT_OF_RESOURCES There is not enough resource for the SetVariable check handler register request.
@retval EFI_UNSUPPORTED This interface is not implemented.
For example, it is unsupported in VarCheck protocol if both VarCheck and SmmVarCheck protocols are present.
**/
EFI_STATUS
EFIAPI
VarCheckRegisterSetVariableCheckHandler (
IN VAR_CHECK_SET_VARIABLE_CHECK_HANDLER Handler
)
{
return EFI_UNSUPPORTED;
}
/**
Variable property set.
@param[in] Name Pointer to the variable name.
@param[in] Guid Pointer to the vendor GUID.
@param[in] VariableProperty Pointer to the input variable property.
@retval EFI_SUCCESS The property of variable specified by the Name and Guid was set successfully.
@retval EFI_INVALID_PARAMETER Name, Guid or VariableProperty is NULL, or Name is an empty string,
or the fields of VariableProperty are not valid.
@retval EFI_ACCESS_DENIED EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
already been signaled.
@retval EFI_OUT_OF_RESOURCES There is not enough resource for the variable property set request.
**/
EFI_STATUS
EFIAPI
VarCheckVariablePropertySet (
IN CHAR16 *Name,
IN EFI_GUID *Guid,
IN VAR_CHECK_VARIABLE_PROPERTY *VariableProperty
)
{
EFI_STATUS Status;
UINTN VariableNameSize;
UINTN PayloadSize;
SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY *CommVariableProperty;
if (Name == NULL || Name[0] == 0 || Guid == NULL) {
return EFI_INVALID_PARAMETER;
}
if (VariableProperty == NULL) {
return EFI_INVALID_PARAMETER;
}
if (VariableProperty->Revision != VAR_CHECK_VARIABLE_PROPERTY_REVISION) {
return EFI_INVALID_PARAMETER;
}
VariableNameSize = StrSize (Name);
CommVariableProperty = NULL;
//
// If VariableName exceeds SMM payload limit. Return failure
//
if (VariableNameSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name)) {
return EFI_INVALID_PARAMETER;
}
AcquireLockOnlyAtBootTime (&mVariableServicesLock);
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + PayloadSize.
//
PayloadSize = OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name) + VariableNameSize;
Status = InitCommunicateBuffer ((VOID **) &CommVariableProperty, PayloadSize, SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_SET);
if (EFI_ERROR (Status)) {
goto Done;
}
ASSERT (CommVariableProperty != NULL);
CopyGuid (&CommVariableProperty->Guid, Guid);
CopyMem (&CommVariableProperty->VariableProperty, VariableProperty, sizeof (*VariableProperty));
CommVariableProperty->NameSize = VariableNameSize;
CopyMem (CommVariableProperty->Name, Name, CommVariableProperty->NameSize);
//
// Send data to SMM.
//
Status = SendCommunicateBuffer (PayloadSize);
Done:
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
Variable property get.
@param[in] Name Pointer to the variable name.
@param[in] Guid Pointer to the vendor GUID.
@param[out] VariableProperty Pointer to the output variable property.
@retval EFI_SUCCESS The property of variable specified by the Name and Guid was got successfully.
@retval EFI_INVALID_PARAMETER Name, Guid or VariableProperty is NULL, or Name is an empty string.
@retval EFI_NOT_FOUND The property of variable specified by the Name and Guid was not found.
**/
EFI_STATUS
EFIAPI
VarCheckVariablePropertyGet (
IN CHAR16 *Name,
IN EFI_GUID *Guid,
OUT VAR_CHECK_VARIABLE_PROPERTY *VariableProperty
)
{
EFI_STATUS Status;
UINTN VariableNameSize;
UINTN PayloadSize;
SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY *CommVariableProperty;
if (Name == NULL || Name[0] == 0 || Guid == NULL) {
return EFI_INVALID_PARAMETER;
}
if (VariableProperty == NULL) {
return EFI_INVALID_PARAMETER;
}
VariableNameSize = StrSize (Name);
CommVariableProperty = NULL;
//
// If VariableName exceeds SMM payload limit. Return failure
//
if (VariableNameSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name)) {
return EFI_INVALID_PARAMETER;
}
AcquireLockOnlyAtBootTime (&mVariableServicesLock);
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + PayloadSize.
//
PayloadSize = OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name) + VariableNameSize;
Status = InitCommunicateBuffer ((VOID **) &CommVariableProperty, PayloadSize, SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_GET);
if (EFI_ERROR (Status)) {
goto Done;
}
ASSERT (CommVariableProperty != NULL);
CopyGuid (&CommVariableProperty->Guid, Guid);
CommVariableProperty->NameSize = VariableNameSize;
CopyMem (CommVariableProperty->Name, Name, CommVariableProperty->NameSize);
//
// Send data to SMM.
//
Status = SendCommunicateBuffer (PayloadSize);
if (Status == EFI_SUCCESS) {
CopyMem (VariableProperty, &CommVariableProperty->VariableProperty, sizeof (*VariableProperty));
}
Done:
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
Signals SMM to synchronize any pending variable updates with the runtime cache(s).
**/
VOID
SyncRuntimeCache (
VOID
)
{
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE.
//
InitCommunicateBuffer (NULL, 0, SMM_VARIABLE_FUNCTION_SYNC_RUNTIME_CACHE);
//
// Send data to SMM.
//
SendCommunicateBuffer (0);
}
/**
Check whether a SMI must be triggered to retrieve pending cache updates.
If the variable HOB was finished being flushed since the last check for a runtime cache update, this function
will prevent the HOB cache from being used for future runtime cache hits.
**/
VOID
CheckForRuntimeCacheSync (
VOID
)
{
if (mVariableRuntimeCachePendingUpdate) {
SyncRuntimeCache ();
}
ASSERT (!mVariableRuntimeCachePendingUpdate);
//
// The HOB variable data may have finished being flushed in the runtime cache sync update
//
if (mHobFlushComplete && mVariableRuntimeHobCacheBuffer != NULL) {
if (!EfiAtRuntime ()) {
FreePages (mVariableRuntimeHobCacheBuffer, EFI_SIZE_TO_PAGES (mVariableRuntimeHobCacheBufferSize));
}
mVariableRuntimeHobCacheBuffer = NULL;
}
}
/**
Finds the given variable in a runtime cache variable store.
Caution: This function may receive untrusted input.
The data size is external input, so this function will validate it carefully to avoid buffer overflow.
@param[in] VariableName Name of Variable to be found.
@param[in] VendorGuid Variable vendor GUID.
@param[out] Attributes Attribute value of the variable found.
@param[in, out] DataSize Size of Data found. If size is less than the
data, this value contains the required size.
@param[out] Data Data pointer.
@retval EFI_SUCCESS Found the specified variable.
@retval EFI_INVALID_PARAMETER Invalid parameter.
@retval EFI_NOT_FOUND The specified variable could not be found.
**/
EFI_STATUS
FindVariableInRuntimeCache (
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid,
OUT UINT32 *Attributes OPTIONAL,
IN OUT UINTN *DataSize,
OUT VOID *Data OPTIONAL
)
{
EFI_STATUS Status;
UINTN TempDataSize;
VARIABLE_POINTER_TRACK RtPtrTrack;
VARIABLE_STORE_TYPE StoreType;
VARIABLE_STORE_HEADER *VariableStoreList[VariableStoreTypeMax];
Status = EFI_NOT_FOUND;
if (VariableName == NULL || VendorGuid == NULL || DataSize == NULL) {
return EFI_INVALID_PARAMETER;
}
ZeroMem (&RtPtrTrack, sizeof (RtPtrTrack));
//
// The UEFI specification restricts Runtime Services callers from invoking the same or certain other Runtime Service
// functions prior to completion and return from a previous Runtime Service call. These restrictions prevent
// a GetVariable () or GetNextVariable () call from being issued until a prior call has returned. The runtime
// cache read lock should always be free when entering this function.
//
ASSERT (!mVariableRuntimeCacheReadLock);
mVariableRuntimeCacheReadLock = TRUE;
CheckForRuntimeCacheSync ();
if (!mVariableRuntimeCachePendingUpdate) {
//
// 0: Volatile, 1: HOB, 2: Non-Volatile.
// The index and attributes mapping must be kept in this order as FindVariable
// makes use of this mapping to implement search algorithm.
//
VariableStoreList[VariableStoreTypeVolatile] = mVariableRuntimeVolatileCacheBuffer;
VariableStoreList[VariableStoreTypeHob] = mVariableRuntimeHobCacheBuffer;
VariableStoreList[VariableStoreTypeNv] = mVariableRuntimeNvCacheBuffer;
for (StoreType = (VARIABLE_STORE_TYPE) 0; StoreType < VariableStoreTypeMax; StoreType++) {
if (VariableStoreList[StoreType] == NULL) {
continue;
}
RtPtrTrack.StartPtr = GetStartPointer (VariableStoreList[StoreType]);
RtPtrTrack.EndPtr = GetEndPointer (VariableStoreList[StoreType]);
RtPtrTrack.Volatile = (BOOLEAN) (StoreType == VariableStoreTypeVolatile);
Status = FindVariableEx (VariableName, VendorGuid, FALSE, &RtPtrTrack, mVariableAuthFormat);
if (!EFI_ERROR (Status)) {
break;
}
}
if (!EFI_ERROR (Status)) {
//
// Get data size
//
TempDataSize = DataSizeOfVariable (RtPtrTrack.CurrPtr, mVariableAuthFormat);
ASSERT (TempDataSize != 0);
if (*DataSize >= TempDataSize) {
if (Data == NULL) {
Status = EFI_INVALID_PARAMETER;
goto Done;
}
CopyMem (Data, GetVariableDataPtr (RtPtrTrack.CurrPtr, mVariableAuthFormat), TempDataSize);
*DataSize = TempDataSize;
UpdateVariableInfo (VariableName, VendorGuid, RtPtrTrack.Volatile, TRUE, FALSE, FALSE, TRUE, &mVariableInfo);
Status = EFI_SUCCESS;
goto Done;
} else {
*DataSize = TempDataSize;
Status = EFI_BUFFER_TOO_SMALL;
goto Done;
}
}
}
Done:
if (Status == EFI_SUCCESS || Status == EFI_BUFFER_TOO_SMALL) {
if (Attributes != NULL && RtPtrTrack.CurrPtr != NULL) {
*Attributes = RtPtrTrack.CurrPtr->Attributes;
}
}
mVariableRuntimeCacheReadLock = FALSE;
return Status;
}
/**
Finds the given variable in a variable store in SMM.
Caution: This function may receive untrusted input.
The data size is external input, so this function will validate it carefully to avoid buffer overflow.
@param[in] VariableName Name of Variable to be found.
@param[in] VendorGuid Variable vendor GUID.
@param[out] Attributes Attribute value of the variable found.
@param[in, out] DataSize Size of Data found. If size is less than the
data, this value contains the required size.
@param[out] Data Data pointer.
@retval EFI_SUCCESS Found the specified variable.
@retval EFI_INVALID_PARAMETER Invalid parameter.
@retval EFI_NOT_FOUND The specified variable could not be found.
**/
EFI_STATUS
FindVariableInSmm (
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid,
OUT UINT32 *Attributes OPTIONAL,
IN OUT UINTN *DataSize,
OUT VOID *Data OPTIONAL
)
{
EFI_STATUS Status;
UINTN PayloadSize;
SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE *SmmVariableHeader;
UINTN TempDataSize;
UINTN VariableNameSize;
if (VariableName == NULL || VendorGuid == NULL || DataSize == NULL) {
return EFI_INVALID_PARAMETER;
}
TempDataSize = *DataSize;
VariableNameSize = StrSize (VariableName);
SmmVariableHeader = NULL;
//
// If VariableName exceeds SMM payload limit. Return failure
//
if (VariableNameSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name)) {
return EFI_INVALID_PARAMETER;
}
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + PayloadSize.
//
if (TempDataSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name) - VariableNameSize) {
//
// If output data buffer exceed SMM payload limit. Trim output buffer to SMM payload size
//
TempDataSize = mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name) - VariableNameSize;
}
PayloadSize = OFFSET_OF (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name) + VariableNameSize + TempDataSize;
Status = InitCommunicateBuffer ((VOID **) &SmmVariableHeader, PayloadSize, SMM_VARIABLE_FUNCTION_GET_VARIABLE);
if (EFI_ERROR (Status)) {
goto Done;
}
ASSERT (SmmVariableHeader != NULL);
CopyGuid (&SmmVariableHeader->Guid, VendorGuid);
SmmVariableHeader->DataSize = TempDataSize;
SmmVariableHeader->NameSize = VariableNameSize;
if (Attributes == NULL) {
SmmVariableHeader->Attributes = 0;
} else {
SmmVariableHeader->Attributes = *Attributes;
}
CopyMem (SmmVariableHeader->Name, VariableName, SmmVariableHeader->NameSize);
//
// Send data to SMM.
//
Status = SendCommunicateBuffer (PayloadSize);
//
// Get data from SMM.
//
if (Status == EFI_SUCCESS || Status == EFI_BUFFER_TOO_SMALL) {
//
// SMM CommBuffer DataSize can be a trimed value
// Only update DataSize when needed
//
*DataSize = SmmVariableHeader->DataSize;
}
if (Attributes != NULL) {
*Attributes = SmmVariableHeader->Attributes;
}
if (EFI_ERROR (Status)) {
goto Done;
}
if (Data != NULL) {
CopyMem (Data, (UINT8 *)SmmVariableHeader->Name + SmmVariableHeader->NameSize, SmmVariableHeader->DataSize);
} else {
Status = EFI_INVALID_PARAMETER;
}
Done:
return Status;
}
/**
This code finds variable in storage blocks (Volatile or Non-Volatile).
Caution: This function may receive untrusted input.
The data size is external input, so this function will validate it carefully to avoid buffer overflow.
@param[in] VariableName Name of Variable to be found.
@param[in] VendorGuid Variable vendor GUID.
@param[out] Attributes Attribute value of the variable found.
@param[in, out] DataSize Size of Data found. If size is less than the
data, this value contains the required size.
@param[out] Data Data pointer.
@retval EFI_INVALID_PARAMETER Invalid parameter.
@retval EFI_SUCCESS Find the specified variable.
@retval EFI_NOT_FOUND Not found.
@retval EFI_BUFFER_TO_SMALL DataSize is too small for the result.
**/
EFI_STATUS
EFIAPI
RuntimeServiceGetVariable (
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid,
OUT UINT32 *Attributes OPTIONAL,
IN OUT UINTN *DataSize,
OUT VOID *Data
)
{
EFI_STATUS Status;
if (VariableName == NULL || VendorGuid == NULL || DataSize == NULL) {
return EFI_INVALID_PARAMETER;
}
if (VariableName[0] == 0) {
return EFI_NOT_FOUND;
}
AcquireLockOnlyAtBootTime (&mVariableServicesLock);
if (FeaturePcdGet (PcdEnableVariableRuntimeCache)) {
Status = FindVariableInRuntimeCache (VariableName, VendorGuid, Attributes, DataSize, Data);
} else {
Status = FindVariableInSmm (VariableName, VendorGuid, Attributes, DataSize, Data);
}
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
Finds the next available variable in a runtime cache variable store.
@param[in, out] VariableNameSize Size of the variable name.
@param[in, out] VariableName Pointer to variable name.
@param[in, out] VendorGuid Variable Vendor Guid.
@retval EFI_INVALID_PARAMETER Invalid parameter.
@retval EFI_SUCCESS Find the specified variable.
@retval EFI_NOT_FOUND Not found.
@retval EFI_BUFFER_TO_SMALL DataSize is too small for the result.
**/
EFI_STATUS
GetNextVariableNameInRuntimeCache (
IN OUT UINTN *VariableNameSize,
IN OUT CHAR16 *VariableName,
IN OUT EFI_GUID *VendorGuid
)
{
EFI_STATUS Status;
UINTN VarNameSize;
VARIABLE_HEADER *VariablePtr;
VARIABLE_STORE_HEADER *VariableStoreHeader[VariableStoreTypeMax];
Status = EFI_NOT_FOUND;
//
// The UEFI specification restricts Runtime Services callers from invoking the same or certain other Runtime Service
// functions prior to completion and return from a previous Runtime Service call. These restrictions prevent
// a GetVariable () or GetNextVariable () call from being issued until a prior call has returned. The runtime
// cache read lock should always be free when entering this function.
//
ASSERT (!mVariableRuntimeCacheReadLock);
CheckForRuntimeCacheSync ();
mVariableRuntimeCacheReadLock = TRUE;
if (!mVariableRuntimeCachePendingUpdate) {
//
// 0: Volatile, 1: HOB, 2: Non-Volatile.
// The index and attributes mapping must be kept in this order as FindVariable
// makes use of this mapping to implement search algorithm.
//
VariableStoreHeader[VariableStoreTypeVolatile] = mVariableRuntimeVolatileCacheBuffer;
VariableStoreHeader[VariableStoreTypeHob] = mVariableRuntimeHobCacheBuffer;
VariableStoreHeader[VariableStoreTypeNv] = mVariableRuntimeNvCacheBuffer;
Status = VariableServiceGetNextVariableInternal (
VariableName,
VendorGuid,
VariableStoreHeader,
&VariablePtr,
mVariableAuthFormat
);
if (!EFI_ERROR (Status)) {
VarNameSize = NameSizeOfVariable (VariablePtr, mVariableAuthFormat);
ASSERT (VarNameSize != 0);
if (VarNameSize <= *VariableNameSize) {
CopyMem (VariableName, GetVariableNamePtr (VariablePtr, mVariableAuthFormat), VarNameSize);
CopyMem (VendorGuid, GetVendorGuidPtr (VariablePtr, mVariableAuthFormat), sizeof (EFI_GUID));
Status = EFI_SUCCESS;
} else {
Status = EFI_BUFFER_TOO_SMALL;
}
*VariableNameSize = VarNameSize;
}
}
mVariableRuntimeCacheReadLock = FALSE;
return Status;
}
/**
Finds the next available variable in a SMM variable store.
@param[in, out] VariableNameSize Size of the variable name.
@param[in, out] VariableName Pointer to variable name.
@param[in, out] VendorGuid Variable Vendor Guid.
@retval EFI_INVALID_PARAMETER Invalid parameter.
@retval EFI_SUCCESS Find the specified variable.
@retval EFI_NOT_FOUND Not found.
@retval EFI_BUFFER_TO_SMALL DataSize is too small for the result.
**/
EFI_STATUS
GetNextVariableNameInSmm (
IN OUT UINTN *VariableNameSize,
IN OUT CHAR16 *VariableName,
IN OUT EFI_GUID *VendorGuid
)
{
EFI_STATUS Status;
UINTN PayloadSize;
SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME *SmmGetNextVariableName;
UINTN OutVariableNameSize;
UINTN InVariableNameSize;
OutVariableNameSize = *VariableNameSize;
InVariableNameSize = StrSize (VariableName);
SmmGetNextVariableName = NULL;
//
// If input string exceeds SMM payload limit. Return failure
//
if (InVariableNameSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME, Name)) {
return EFI_INVALID_PARAMETER;
}
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + PayloadSize.
//
if (OutVariableNameSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME, Name)) {
//
// If output buffer exceed SMM payload limit. Trim output buffer to SMM payload size
//
OutVariableNameSize = mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME, Name);
}
//
// Payload should be Guid + NameSize + MAX of Input & Output buffer
//
PayloadSize = OFFSET_OF (SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME, Name) + MAX (OutVariableNameSize, InVariableNameSize);
Status = InitCommunicateBuffer ((VOID **)&SmmGetNextVariableName, PayloadSize, SMM_VARIABLE_FUNCTION_GET_NEXT_VARIABLE_NAME);
if (EFI_ERROR (Status)) {
goto Done;
}
ASSERT (SmmGetNextVariableName != NULL);
//
// SMM comm buffer->NameSize is buffer size for return string
//
SmmGetNextVariableName->NameSize = OutVariableNameSize;
CopyGuid (&SmmGetNextVariableName->Guid, VendorGuid);
//
// Copy whole string
//
CopyMem (SmmGetNextVariableName->Name, VariableName, InVariableNameSize);
if (OutVariableNameSize > InVariableNameSize) {
ZeroMem ((UINT8 *) SmmGetNextVariableName->Name + InVariableNameSize, OutVariableNameSize - InVariableNameSize);
}
//
// Send data to SMM
//
Status = SendCommunicateBuffer (PayloadSize);
//
// Get data from SMM.
//
if (Status == EFI_SUCCESS || Status == EFI_BUFFER_TOO_SMALL) {
//
// SMM CommBuffer NameSize can be a trimed value
// Only update VariableNameSize when needed
//
*VariableNameSize = SmmGetNextVariableName->NameSize;
}
if (EFI_ERROR (Status)) {
goto Done;
}
CopyGuid (VendorGuid, &SmmGetNextVariableName->Guid);
CopyMem (VariableName, SmmGetNextVariableName->Name, SmmGetNextVariableName->NameSize);
Done:
return Status;
}
/**
This code Finds the Next available variable.
@param[in, out] VariableNameSize Size of the variable name.
@param[in, out] VariableName Pointer to variable name.
@param[in, out] VendorGuid Variable Vendor Guid.
@retval EFI_INVALID_PARAMETER Invalid parameter.
@retval EFI_SUCCESS Find the specified variable.
@retval EFI_NOT_FOUND Not found.
@retval EFI_BUFFER_TO_SMALL DataSize is too small for the result.
**/
EFI_STATUS
EFIAPI
RuntimeServiceGetNextVariableName (
IN OUT UINTN *VariableNameSize,
IN OUT CHAR16 *VariableName,
IN OUT EFI_GUID *VendorGuid
)
{
EFI_STATUS Status;
UINTN MaxLen;
Status = EFI_NOT_FOUND;
if (VariableNameSize == NULL || VariableName == NULL || VendorGuid == NULL) {
return EFI_INVALID_PARAMETER;
}
//
// Calculate the possible maximum length of name string, including the Null terminator.
//
MaxLen = *VariableNameSize / sizeof (CHAR16);
if ((MaxLen == 0) || (StrnLenS (VariableName, MaxLen) == MaxLen)) {
//
// Null-terminator is not found in the first VariableNameSize bytes of the input VariableName buffer,
// follow spec to return EFI_INVALID_PARAMETER.
//
return EFI_INVALID_PARAMETER;
}
AcquireLockOnlyAtBootTime (&mVariableServicesLock);
if (FeaturePcdGet (PcdEnableVariableRuntimeCache)) {
Status = GetNextVariableNameInRuntimeCache (VariableNameSize, VariableName, VendorGuid);
} else {
Status = GetNextVariableNameInSmm (VariableNameSize, VariableName, VendorGuid);
}
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
This code sets variable in storage blocks (Volatile or Non-Volatile).
Caution: This function may receive untrusted input.
The data size and data are external input, so this function will validate it carefully to avoid buffer overflow.
@param[in] VariableName Name of Variable to be found.
@param[in] VendorGuid Variable vendor GUID.
@param[in] Attributes Attribute value of the variable found
@param[in] DataSize Size of Data found. If size is less than the
data, this value contains the required size.
@param[in] Data Data pointer.
@retval EFI_INVALID_PARAMETER Invalid parameter.
@retval EFI_SUCCESS Set successfully.
@retval EFI_OUT_OF_RESOURCES Resource not enough to set variable.
@retval EFI_NOT_FOUND Not found.
@retval EFI_WRITE_PROTECTED Variable is read-only.
**/
EFI_STATUS
EFIAPI
RuntimeServiceSetVariable (
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid,
IN UINT32 Attributes,
IN UINTN DataSize,
IN VOID *Data
)
{
EFI_STATUS Status;
UINTN PayloadSize;
SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE *SmmVariableHeader;
UINTN VariableNameSize;
//
// Check input parameters.
//
if (VariableName == NULL || VariableName[0] == 0 || VendorGuid == NULL) {
return EFI_INVALID_PARAMETER;
}
if (DataSize != 0 && Data == NULL) {
return EFI_INVALID_PARAMETER;
}
VariableNameSize = StrSize (VariableName);
SmmVariableHeader = NULL;
//
// If VariableName or DataSize exceeds SMM payload limit. Return failure
//
if ((VariableNameSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name)) ||
(DataSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name) - VariableNameSize)){
return EFI_INVALID_PARAMETER;
}
AcquireLockOnlyAtBootTime(&mVariableServicesLock);
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + PayloadSize.
//
PayloadSize = OFFSET_OF (SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE, Name) + VariableNameSize + DataSize;
Status = InitCommunicateBuffer ((VOID **)&SmmVariableHeader, PayloadSize, SMM_VARIABLE_FUNCTION_SET_VARIABLE);
if (EFI_ERROR (Status)) {
goto Done;
}
ASSERT (SmmVariableHeader != NULL);
CopyGuid ((EFI_GUID *) &SmmVariableHeader->Guid, VendorGuid);
SmmVariableHeader->DataSize = DataSize;
SmmVariableHeader->NameSize = VariableNameSize;
SmmVariableHeader->Attributes = Attributes;
CopyMem (SmmVariableHeader->Name, VariableName, SmmVariableHeader->NameSize);
CopyMem ((UINT8 *) SmmVariableHeader->Name + SmmVariableHeader->NameSize, Data, DataSize);
//
// Send data to SMM.
//
Status = SendCommunicateBuffer (PayloadSize);
Done:
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
if (!EfiAtRuntime ()) {
if (!EFI_ERROR (Status)) {
SecureBootHook (
VariableName,
VendorGuid
);
}
}
return Status;
}
/**
This code returns information about the EFI variables.
@param[in] Attributes Attributes bitmask to specify the type of variables
on which to return information.
@param[out] MaximumVariableStorageSize Pointer to the maximum size of the storage space available
for the EFI variables associated with the attributes specified.
@param[out] RemainingVariableStorageSize Pointer to the remaining size of the storage space available
for EFI variables associated with the attributes specified.
@param[out] MaximumVariableSize Pointer to the maximum size of an individual EFI variables
associated with the attributes specified.
@retval EFI_INVALID_PARAMETER An invalid combination of attribute bits was supplied.
@retval EFI_SUCCESS Query successfully.
@retval EFI_UNSUPPORTED The attribute is not supported on this platform.
**/
EFI_STATUS
EFIAPI
RuntimeServiceQueryVariableInfo (
IN UINT32 Attributes,
OUT UINT64 *MaximumVariableStorageSize,
OUT UINT64 *RemainingVariableStorageSize,
OUT UINT64 *MaximumVariableSize
)
{
EFI_STATUS Status;
UINTN PayloadSize;
SMM_VARIABLE_COMMUNICATE_QUERY_VARIABLE_INFO *SmmQueryVariableInfo;
SmmQueryVariableInfo = NULL;
if(MaximumVariableStorageSize == NULL || RemainingVariableStorageSize == NULL || MaximumVariableSize == NULL || Attributes == 0) {
return EFI_INVALID_PARAMETER;
}
AcquireLockOnlyAtBootTime(&mVariableServicesLock);
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + PayloadSize;
//
PayloadSize = sizeof (SMM_VARIABLE_COMMUNICATE_QUERY_VARIABLE_INFO);
Status = InitCommunicateBuffer ((VOID **)&SmmQueryVariableInfo, PayloadSize, SMM_VARIABLE_FUNCTION_QUERY_VARIABLE_INFO);
if (EFI_ERROR (Status)) {
goto Done;
}
ASSERT (SmmQueryVariableInfo != NULL);
SmmQueryVariableInfo->Attributes = Attributes;
//
// Send data to SMM.
//
Status = SendCommunicateBuffer (PayloadSize);
if (EFI_ERROR (Status)) {
goto Done;
}
//
// Get data from SMM.
//
*MaximumVariableSize = SmmQueryVariableInfo->MaximumVariableSize;
*MaximumVariableStorageSize = SmmQueryVariableInfo->MaximumVariableStorageSize;
*RemainingVariableStorageSize = SmmQueryVariableInfo->RemainingVariableStorageSize;
Done:
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
Exit Boot Services Event notification handler.
Notify SMM variable driver about the event.
@param[in] Event Event whose notification function is being invoked.
@param[in] Context Pointer to the notification function's context.
**/
VOID
EFIAPI
OnExitBootServices (
IN EFI_EVENT Event,
IN VOID *Context
)
{
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE.
//
InitCommunicateBuffer (NULL, 0, SMM_VARIABLE_FUNCTION_EXIT_BOOT_SERVICE);
//
// Send data to SMM.
//
SendCommunicateBuffer (0);
}
/**
On Ready To Boot Services Event notification handler.
Notify SMM variable driver about the event.
@param[in] Event Event whose notification function is being invoked
@param[in] Context Pointer to the notification function's context
**/
VOID
EFIAPI
OnReadyToBoot (
IN EFI_EVENT Event,
IN VOID *Context
)
{
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE.
//
InitCommunicateBuffer (NULL, 0, SMM_VARIABLE_FUNCTION_READY_TO_BOOT);
//
// Send data to SMM.
//
SendCommunicateBuffer (0);
//
// Install the system configuration table for variable info data captured
//
if (FeaturePcdGet (PcdEnableVariableRuntimeCache) && FeaturePcdGet (PcdVariableCollectStatistics)) {
if (mVariableAuthFormat) {
gBS->InstallConfigurationTable (&gEfiAuthenticatedVariableGuid, mVariableInfo);
} else {
gBS->InstallConfigurationTable (&gEfiVariableGuid, mVariableInfo);
}
}
gBS->CloseEvent (Event);
}
/**
Notification function of EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE.
This is a notification function registered on EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
It convers pointer to new virtual address.
@param[in] Event Event whose notification function is being invoked.
@param[in] Context Pointer to the notification function's context.
**/
VOID
EFIAPI
VariableAddressChangeEvent (
IN EFI_EVENT Event,
IN VOID *Context
)
{
EfiConvertPointer (0x0, (VOID **) &mVariableBuffer);
EfiConvertPointer (0x0, (VOID **) &mMmCommunication2);
EfiConvertPointer (EFI_OPTIONAL_PTR, (VOID **) &mVariableRuntimeHobCacheBuffer);
EfiConvertPointer (EFI_OPTIONAL_PTR, (VOID **) &mVariableRuntimeNvCacheBuffer);
EfiConvertPointer (EFI_OPTIONAL_PTR, (VOID **) &mVariableRuntimeVolatileCacheBuffer);
}
/**
This code gets variable payload size.
@param[out] VariablePayloadSize Output pointer to variable payload size.
@retval EFI_SUCCESS Get successfully.
@retval Others Get unsuccessfully.
**/
EFI_STATUS
EFIAPI
GetVariablePayloadSize (
OUT UINTN *VariablePayloadSize
)
{
EFI_STATUS Status;
SMM_VARIABLE_COMMUNICATE_GET_PAYLOAD_SIZE *SmmGetPayloadSize;
EFI_MM_COMMUNICATE_HEADER *SmmCommunicateHeader;
SMM_VARIABLE_COMMUNICATE_HEADER *SmmVariableFunctionHeader;
UINTN CommSize;
UINT8 *CommBuffer;
SmmGetPayloadSize = NULL;
CommBuffer = NULL;
if(VariablePayloadSize == NULL) {
return EFI_INVALID_PARAMETER;
}
AcquireLockOnlyAtBootTime(&mVariableServicesLock);
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + sizeof (SMM_VARIABLE_COMMUNICATE_GET_PAYLOAD_SIZE);
//
CommSize = SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + sizeof (SMM_VARIABLE_COMMUNICATE_GET_PAYLOAD_SIZE);
CommBuffer = AllocateZeroPool (CommSize);
if (CommBuffer == NULL) {
Status = EFI_OUT_OF_RESOURCES;
goto Done;
}
SmmCommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *) CommBuffer;
CopyGuid (&SmmCommunicateHeader->HeaderGuid, &gEfiSmmVariableProtocolGuid);
SmmCommunicateHeader->MessageLength = SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + sizeof (SMM_VARIABLE_COMMUNICATE_GET_PAYLOAD_SIZE);
SmmVariableFunctionHeader = (SMM_VARIABLE_COMMUNICATE_HEADER *) SmmCommunicateHeader->Data;
SmmVariableFunctionHeader->Function = SMM_VARIABLE_FUNCTION_GET_PAYLOAD_SIZE;
SmmGetPayloadSize = (SMM_VARIABLE_COMMUNICATE_GET_PAYLOAD_SIZE *) SmmVariableFunctionHeader->Data;
//
// Send data to SMM.
//
Status = mMmCommunication2->Communicate (mMmCommunication2, CommBuffer, CommBuffer, &CommSize);
ASSERT_EFI_ERROR (Status);
Status = SmmVariableFunctionHeader->ReturnStatus;
if (EFI_ERROR (Status)) {
goto Done;
}
//
// Get data from SMM.
//
*VariablePayloadSize = SmmGetPayloadSize->VariablePayloadSize;
Done:
if (CommBuffer != NULL) {
FreePool (CommBuffer);
}
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
This code gets information needed from SMM for runtime cache initialization.
@param[out] TotalHobStorageSize Output pointer for the total HOB storage size in bytes.
@param[out] TotalNvStorageSize Output pointer for the total non-volatile storage size in bytes.
@param[out] TotalVolatileStorageSize Output pointer for the total volatile storage size in bytes.
@param[out] AuthenticatedVariableUsage Output pointer that indicates if authenticated variables are to be used.
@retval EFI_SUCCESS Retrieved the size successfully.
@retval EFI_INVALID_PARAMETER TotalNvStorageSize parameter is NULL.
@retval EFI_OUT_OF_RESOURCES The memory resources needed for a CommBuffer are not available.
@retval Others Could not retrieve the size successfully.
**/
EFI_STATUS
GetRuntimeCacheInfo (
OUT UINTN *TotalHobStorageSize,
OUT UINTN *TotalNvStorageSize,
OUT UINTN *TotalVolatileStorageSize,
OUT BOOLEAN *AuthenticatedVariableUsage
)
{
EFI_STATUS Status;
SMM_VARIABLE_COMMUNICATE_GET_RUNTIME_CACHE_INFO *SmmGetRuntimeCacheInfo;
EFI_MM_COMMUNICATE_HEADER *SmmCommunicateHeader;
SMM_VARIABLE_COMMUNICATE_HEADER *SmmVariableFunctionHeader;
UINTN CommSize;
UINT8 *CommBuffer;
SmmGetRuntimeCacheInfo = NULL;
CommBuffer = mVariableBuffer;
if (TotalHobStorageSize == NULL || TotalNvStorageSize == NULL || TotalVolatileStorageSize == NULL || AuthenticatedVariableUsage == NULL) {
return EFI_INVALID_PARAMETER;
}
if (CommBuffer == NULL) {
return EFI_OUT_OF_RESOURCES;
}
AcquireLockOnlyAtBootTime (&mVariableServicesLock);
CommSize = SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + sizeof (SMM_VARIABLE_COMMUNICATE_GET_RUNTIME_CACHE_INFO);
ZeroMem (CommBuffer, CommSize);
SmmCommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *) CommBuffer;
CopyGuid (&SmmCommunicateHeader->HeaderGuid, &gEfiSmmVariableProtocolGuid);
SmmCommunicateHeader->MessageLength = SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + sizeof (SMM_VARIABLE_COMMUNICATE_GET_RUNTIME_CACHE_INFO);
SmmVariableFunctionHeader = (SMM_VARIABLE_COMMUNICATE_HEADER *) SmmCommunicateHeader->Data;
SmmVariableFunctionHeader->Function = SMM_VARIABLE_FUNCTION_GET_RUNTIME_CACHE_INFO;
SmmGetRuntimeCacheInfo = (SMM_VARIABLE_COMMUNICATE_GET_RUNTIME_CACHE_INFO *) SmmVariableFunctionHeader->Data;
//
// Send data to SMM.
//
Status = mMmCommunication2->Communicate (mMmCommunication2, CommBuffer, CommBuffer, &CommSize);
ASSERT_EFI_ERROR (Status);
if (CommSize <= SMM_VARIABLE_COMMUNICATE_HEADER_SIZE) {
Status = EFI_BAD_BUFFER_SIZE;
goto Done;
}
Status = SmmVariableFunctionHeader->ReturnStatus;
if (EFI_ERROR (Status)) {
goto Done;
}
//
// Get data from SMM.
//
*TotalHobStorageSize = SmmGetRuntimeCacheInfo->TotalHobStorageSize;
*TotalNvStorageSize = SmmGetRuntimeCacheInfo->TotalNvStorageSize;
*TotalVolatileStorageSize = SmmGetRuntimeCacheInfo->TotalVolatileStorageSize;
*AuthenticatedVariableUsage = SmmGetRuntimeCacheInfo->AuthenticatedVariableUsage;
Done:
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
Sends the runtime variable cache context information to SMM.
@retval EFI_SUCCESS Retrieved the size successfully.
@retval EFI_INVALID_PARAMETER TotalNvStorageSize parameter is NULL.
@retval EFI_OUT_OF_RESOURCES The memory resources needed for a CommBuffer are not available.
@retval Others Could not retrieve the size successfully.;
**/
EFI_STATUS
SendRuntimeVariableCacheContextToSmm (
VOID
)
{
EFI_STATUS Status;
SMM_VARIABLE_COMMUNICATE_RUNTIME_VARIABLE_CACHE_CONTEXT *SmmRuntimeVarCacheContext;
EFI_MM_COMMUNICATE_HEADER *SmmCommunicateHeader;
SMM_VARIABLE_COMMUNICATE_HEADER *SmmVariableFunctionHeader;
UINTN CommSize;
UINT8 *CommBuffer;
SmmRuntimeVarCacheContext = NULL;
CommBuffer = mVariableBuffer;
if (CommBuffer == NULL) {
return EFI_OUT_OF_RESOURCES;
}
AcquireLockOnlyAtBootTime (&mVariableServicesLock);
//
// Init the communicate buffer. The buffer data size is:
// SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + sizeof (SMM_VARIABLE_COMMUNICATE_RUNTIME_VARIABLE_CACHE_CONTEXT);
//
CommSize = SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + sizeof (SMM_VARIABLE_COMMUNICATE_RUNTIME_VARIABLE_CACHE_CONTEXT);
ZeroMem (CommBuffer, CommSize);
SmmCommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *) CommBuffer;
CopyGuid (&SmmCommunicateHeader->HeaderGuid, &gEfiSmmVariableProtocolGuid);
SmmCommunicateHeader->MessageLength = SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + sizeof (SMM_VARIABLE_COMMUNICATE_RUNTIME_VARIABLE_CACHE_CONTEXT);
SmmVariableFunctionHeader = (SMM_VARIABLE_COMMUNICATE_HEADER *) SmmCommunicateHeader->Data;
SmmVariableFunctionHeader->Function = SMM_VARIABLE_FUNCTION_INIT_RUNTIME_VARIABLE_CACHE_CONTEXT;
SmmRuntimeVarCacheContext = (SMM_VARIABLE_COMMUNICATE_RUNTIME_VARIABLE_CACHE_CONTEXT *) SmmVariableFunctionHeader->Data;
SmmRuntimeVarCacheContext->RuntimeHobCache = mVariableRuntimeHobCacheBuffer;
SmmRuntimeVarCacheContext->RuntimeVolatileCache = mVariableRuntimeVolatileCacheBuffer;
SmmRuntimeVarCacheContext->RuntimeNvCache = mVariableRuntimeNvCacheBuffer;
SmmRuntimeVarCacheContext->PendingUpdate = &mVariableRuntimeCachePendingUpdate;
SmmRuntimeVarCacheContext->ReadLock = &mVariableRuntimeCacheReadLock;
SmmRuntimeVarCacheContext->HobFlushComplete = &mHobFlushComplete;
//
// Send data to SMM.
//
Status = mMmCommunication2->Communicate (mMmCommunication2, CommBuffer, CommBuffer, &CommSize);
ASSERT_EFI_ERROR (Status);
if (CommSize <= SMM_VARIABLE_COMMUNICATE_HEADER_SIZE) {
Status = EFI_BAD_BUFFER_SIZE;
goto Done;
}
Status = SmmVariableFunctionHeader->ReturnStatus;
if (EFI_ERROR (Status)) {
goto Done;
}
Done:
ReleaseLockOnlyAtBootTime (&mVariableServicesLock);
return Status;
}
/**
Initialize variable service and install Variable Architectural protocol.
@param[in] Event Event whose notification function is being invoked.
@param[in] Context Pointer to the notification function's context.
**/
VOID
EFIAPI
SmmVariableReady (
IN EFI_EVENT Event,
IN VOID *Context
)
{
EFI_STATUS Status;
Status = gBS->LocateProtocol (&gEfiSmmVariableProtocolGuid, NULL, (VOID **) &mSmmVariable);
if (EFI_ERROR (Status)) {
return;
}
Status = gBS->LocateProtocol (&gEfiMmCommunication2ProtocolGuid, NULL, (VOID **) &mMmCommunication2);
ASSERT_EFI_ERROR (Status);
//
// Allocate memory for variable communicate buffer.
//
Status = GetVariablePayloadSize (&mVariableBufferPayloadSize);
ASSERT_EFI_ERROR (Status);
mVariableBufferSize = SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + mVariableBufferPayloadSize;
mVariableBuffer = AllocateRuntimePool (mVariableBufferSize);
ASSERT (mVariableBuffer != NULL);
//
// Save the buffer physical address used for SMM conmunication.
//
mVariableBufferPhysical = mVariableBuffer;
if (FeaturePcdGet (PcdEnableVariableRuntimeCache)) {
DEBUG ((DEBUG_INFO, "Variable driver runtime cache is enabled.\n"));
//
// Allocate runtime variable cache memory buffers.
//
Status = GetRuntimeCacheInfo (
&mVariableRuntimeHobCacheBufferSize,
&mVariableRuntimeNvCacheBufferSize,
&mVariableRuntimeVolatileCacheBufferSize,
&mVariableAuthFormat
);
if (!EFI_ERROR (Status)) {
Status = InitVariableCache (&mVariableRuntimeHobCacheBuffer, &mVariableRuntimeHobCacheBufferSize);
if (!EFI_ERROR (Status)) {
Status = InitVariableCache (&mVariableRuntimeNvCacheBuffer, &mVariableRuntimeNvCacheBufferSize);
if (!EFI_ERROR (Status)) {
Status = InitVariableCache (&mVariableRuntimeVolatileCacheBuffer, &mVariableRuntimeVolatileCacheBufferSize);
if (!EFI_ERROR (Status)) {
Status = SendRuntimeVariableCacheContextToSmm ();
if (!EFI_ERROR (Status)) {
SyncRuntimeCache ();
}
}
}
}
if (EFI_ERROR (Status)) {
mVariableRuntimeHobCacheBuffer = NULL;
mVariableRuntimeNvCacheBuffer = NULL;
mVariableRuntimeVolatileCacheBuffer = NULL;
}
}
ASSERT_EFI_ERROR (Status);
} else {
DEBUG ((DEBUG_INFO, "Variable driver runtime cache is disabled.\n"));
}
gRT->GetVariable = RuntimeServiceGetVariable;
gRT->GetNextVariableName = RuntimeServiceGetNextVariableName;
gRT->SetVariable = RuntimeServiceSetVariable;
gRT->QueryVariableInfo = RuntimeServiceQueryVariableInfo;
//
// Install the Variable Architectural Protocol on a new handle.
//
Status = gBS->InstallProtocolInterface (
&mHandle,
&gEfiVariableArchProtocolGuid,
EFI_NATIVE_INTERFACE,
NULL
);
ASSERT_EFI_ERROR (Status);
mVariableLock.RequestToLock = VariableLockRequestToLock;
Status = gBS->InstallMultipleProtocolInterfaces (
&mHandle,
&gEdkiiVariableLockProtocolGuid,
&mVariableLock,
NULL
);
ASSERT_EFI_ERROR (Status);
mVarCheck.RegisterSetVariableCheckHandler = VarCheckRegisterSetVariableCheckHandler;
mVarCheck.VariablePropertySet = VarCheckVariablePropertySet;
mVarCheck.VariablePropertyGet = VarCheckVariablePropertyGet;
Status = gBS->InstallMultipleProtocolInterfaces (
&mHandle,
&gEdkiiVarCheckProtocolGuid,
&mVarCheck,
NULL
);
ASSERT_EFI_ERROR (Status);
gBS->CloseEvent (Event);
}
/**
SMM Non-Volatile variable write service is ready notify event handler.
@param[in] Event Event whose notification function is being invoked.
@param[in] Context Pointer to the notification function's context.
**/
VOID
EFIAPI
SmmVariableWriteReady (
IN EFI_EVENT Event,
IN VOID *Context
)
{
EFI_STATUS Status;
VOID *ProtocolOps;
//
// Check whether the protocol is installed or not.
//
Status = gBS->LocateProtocol (&gSmmVariableWriteGuid, NULL, (VOID **) &ProtocolOps);
if (EFI_ERROR (Status)) {
return;
}
//
// Some Secure Boot Policy Var (SecureBoot, etc) updates following other
// Secure Boot Policy Variable change. Record their initial value.
//
RecordSecureBootPolicyVarData();
Status = gBS->InstallProtocolInterface (
&mHandle,
&gEfiVariableWriteArchProtocolGuid,
EFI_NATIVE_INTERFACE,
NULL
);
ASSERT_EFI_ERROR (Status);
gBS->CloseEvent (Event);
}
/**
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
VariableSmmRuntimeInitialize (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
VOID *SmmVariableRegistration;
VOID *SmmVariableWriteRegistration;
EFI_EVENT OnReadyToBootEvent;
EFI_EVENT ExitBootServiceEvent;
EFI_EVENT LegacyBootEvent;
EfiInitializeLock (&mVariableServicesLock, TPL_NOTIFY);
//
// Smm variable service is ready
//
EfiCreateProtocolNotifyEvent (
&gEfiSmmVariableProtocolGuid,
TPL_CALLBACK,
SmmVariableReady,
NULL,
&SmmVariableRegistration
);
//
// Smm Non-Volatile variable write service is ready
//
EfiCreateProtocolNotifyEvent (
&gSmmVariableWriteGuid,
TPL_CALLBACK,
SmmVariableWriteReady,
NULL,
&SmmVariableWriteRegistration
);
//
// Register the event to reclaim variable for OS usage.
//
EfiCreateEventReadyToBootEx (
TPL_NOTIFY,
OnReadyToBoot,
NULL,
&OnReadyToBootEvent
);
//
// Register the event to inform SMM variable that it is at runtime.
//
gBS->CreateEventEx (
EVT_NOTIFY_SIGNAL,
TPL_NOTIFY,
OnExitBootServices,
NULL,
&gEfiEventExitBootServicesGuid,
&ExitBootServiceEvent
);
//
// Register the event to inform SMM variable that it is at runtime for legacy boot.
// Reuse OnExitBootServices() here.
//
EfiCreateEventLegacyBootEx(
TPL_NOTIFY,
OnExitBootServices,
NULL,
&LegacyBootEvent
);
//
// Register the event to convert the pointer for runtime.
//
gBS->CreateEventEx (
EVT_NOTIFY_SIGNAL,
TPL_NOTIFY,
VariableAddressChangeEvent,
NULL,
&gEfiEventVirtualAddressChangeGuid,
&mVirtualAddressChangeEvent
);
// Initialize the VariablePolicy protocol and engine.
VariablePolicySmmDxeMain (ImageHandle, SystemTable);
return EFI_SUCCESS;
}