/* Derived from source code of TrueCrypt 7.1a, which is Copyright (c) 2008-2012 TrueCrypt Developers Association and which is governed by the TrueCrypt License 3.0. Modifications and additions to the original source code (contained in this file) and all other portions of this file are Copyright (c) 2013-2015 IDRIX and are governed by the Apache License 2.0 the full text of which is contained in the file License.txt included in VeraCrypt binary and source code distribution packages. */ #include "TCdefs.h" #include "Apidrvr.h" #include "Ntdriver.h" #include "DriveFilter.h" #include "EncryptedIoQueue.h" #include "EncryptionThreadPool.h" #include "Volumes.h" #include <IntSafe.h> static void AcquireBufferPoolMutex (EncryptedIoQueue *queue) { NTSTATUS status; status = KeWaitForMutexObject (&queue->BufferPoolMutex, Executive, KernelMode, FALSE, NULL); if (!NT_SUCCESS (status)) TC_BUG_CHECK (status); } static void ReleaseBufferPoolMutex (EncryptedIoQueue *queue) { KeReleaseMutex (&queue->BufferPoolMutex, FALSE); } static void *GetPoolBuffer (EncryptedIoQueue *queue, ULONG requestedSize) { EncryptedIoQueueBuffer *buffer; void *bufferAddress = NULL; BOOL requestedSizePresentInPool = FALSE; while (TRUE) { AcquireBufferPoolMutex (queue); for (buffer = queue->FirstPoolBuffer; ; buffer = buffer->NextBuffer) { if (buffer && buffer->Size == requestedSize) { requestedSizePresentInPool = TRUE; if (!buffer->InUse) { // Reuse a free buffer buffer->InUse = TRUE; bufferAddress = buffer->Address; break; } } if (!buffer || !buffer->NextBuffer) { EncryptedIoQueueBuffer *newBuffer; if (requestedSizePresentInPool && !queue->StartPending) break; // Allocate a new buffer newBuffer = TCalloc (sizeof (EncryptedIoQueueBuffer)); if (!newBuffer) { bufferAddress = NULL; break; } bufferAddress = TCalloc (requestedSize); if (bufferAddress) { newBuffer->NextBuffer = NULL; newBuffer->Address = bufferAddress; newBuffer->Size = requestedSize; newBuffer->InUse = TRUE; if (!buffer) queue->FirstPoolBuffer = newBuffer; else buffer->NextBuffer = newBuffer; } else TCfree (newBuffer); break; } } ReleaseBufferPoolMutex (queue); if (bufferAddress || !requestedSizePresentInPool || queue->StartPending) break; KeWaitForSingleObject (&queue->PoolBufferFreeEvent, Executive, KernelMode, FALSE, NULL); } return bufferAddress; } static void ReleasePoolBuffer (EncryptedIoQueue *queue, void *address) { EncryptedIoQueueBuffer *buffer; AcquireBufferPoolMutex (queue); for (buffer = queue->FirstPoolBuffer; buffer != NULL; buffer = buffer->NextBuffer) { if (buffer->Address == address) { ASSERT (buffer->InUse); buffer->InUse = FALSE; break; } } ReleaseBufferPoolMutex (queue); KeSetEvent (&queue->PoolBufferFreeEvent, IO_DISK_INCREMENT, FALSE); } static void FreePoolBuffers (EncryptedIoQueue *queue) { EncryptedIoQueueBuffer *buffer; AcquireBufferPoolMutex (queue); for (buffer = queue->FirstPoolBuffer; buffer != NULL; ) { EncryptedIoQueueBuffer *nextBuffer = buffer->NextBuffer; ASSERT (!buffer->InUse || queue->StartPending); TCfree (buffer->Address); TCfree (buffer); buffer = nextBuffer; } queue->FirstPoolBuffer = NULL; ReleaseBufferPoolMutex (queue); } static void DecrementOutstandingIoCount (EncryptedIoQueue *queue) { if (InterlockedDecrement (&queue->OutstandingIoCount) == 0 && (queue->SuspendPending || queue->StopPending)) KeSetEvent (&queue->NoOutstandingIoEvent, IO_DISK_INCREMENT, FALSE); } static void OnItemCompleted (EncryptedIoQueueItem *item, BOOL freeItem) { DecrementOutstandingIoCount (item->Queue); IoReleaseRemoveLock (&item->Queue->RemoveLock, item->OriginalIrp); if (NT_SUCCESS (item->Status)) { if (item->Write) item->Queue->TotalBytesWritten += item->OriginalLength; else item->Queue->TotalBytesRead += item->OriginalLength; } if (freeItem) ReleasePoolBuffer (item->Queue, item); } static NTSTATUS CompleteOriginalIrp (EncryptedIoQueueItem *item, NTSTATUS status, ULONG_PTR information) { #ifdef TC_TRACE_IO_QUEUE Dump ("< %I64d [%I64d] %c status=%x info=%I64d\n", item->OriginalIrpOffset, GetElapsedTime (&item->Queue->LastPerformanceCounter), item->Write ? 'W' : 'R', status, (int64) information); #endif TCCompleteDiskIrp (item->OriginalIrp, status, information); item->Status = status; OnItemCompleted (item, TRUE); return status; } static void AcquireFragmentBuffer (EncryptedIoQueue *queue, byte *buffer) { NTSTATUS status = STATUS_INVALID_PARAMETER; if (buffer == queue->FragmentBufferA) { status = KeWaitForSingleObject (&queue->FragmentBufferAFreeEvent, Executive, KernelMode, FALSE, NULL); } else if (buffer == queue->FragmentBufferB) { status = KeWaitForSingleObject (&queue->FragmentBufferBFreeEvent, Executive, KernelMode, FALSE, NULL); } if (!NT_SUCCESS (status)) TC_BUG_CHECK (status); } static void ReleaseFragmentBuffer (EncryptedIoQueue *queue, byte *buffer) { if (buffer == queue->FragmentBufferA) { KeSetEvent (&queue->FragmentBufferAFreeEvent, IO_DISK_INCREMENT, FALSE); } else if (buffer == queue->FragmentBufferB) { KeSetEvent (&queue->FragmentBufferBFreeEvent, IO_DISK_INCREMENT, FALSE); } else { TC_BUG_CHECK (STATUS_INVALID_PARAMETER); } } static VOID CompletionThreadProc (PVOID threadArg) { EncryptedIoQueue *queue = (EncryptedIoQueue *) threadArg; PLIST_ENTRY listEntry; EncryptedIoRequest *request; UINT64_STRUCT dataUnit; if (IsEncryptionThreadPoolRunning()) KeSetPriorityThread (KeGetCurrentThread(), LOW_REALTIME_PRIORITY); while (!queue->ThreadExitRequested) { if (!NT_SUCCESS (KeWaitForSingleObject (&queue->CompletionThreadQueueNotEmptyEvent, Executive, KernelMode, FALSE, NULL))) continue; if (queue->ThreadExitRequested) break; while ((listEntry = ExInterlockedRemoveHeadList (&queue->CompletionThreadQueue, &queue->CompletionThreadQueueLock))) { request = CONTAINING_RECORD (listEntry, EncryptedIoRequest, CompletionListEntry); if (request->EncryptedLength > 0 && NT_SUCCESS (request->Item->Status)) { ASSERT (request->EncryptedOffset + request->EncryptedLength <= request->Offset.QuadPart + request->Length); dataUnit.Value = (request->Offset.QuadPart + request->EncryptedOffset) / ENCRYPTION_DATA_UNIT_SIZE; if (queue->CryptoInfo->bPartitionInInactiveSysEncScope) dataUnit.Value += queue->CryptoInfo->FirstDataUnitNo.Value; else if (queue->RemapEncryptedArea) dataUnit.Value += queue->RemappedAreaDataUnitOffset; DecryptDataUnits (request->Data + request->EncryptedOffset, &dataUnit, request->EncryptedLength / ENCRYPTION_DATA_UNIT_SIZE, queue->CryptoInfo); } if (request->CompleteOriginalIrp) { CompleteOriginalIrp (request->Item, request->Item->Status, NT_SUCCESS (request->Item->Status) ? request->Item->OriginalLength : 0); } ReleasePoolBuffer (queue, request); } } PsTerminateSystemThread (STATUS_SUCCESS); } static NTSTATUS TCCachedRead (EncryptedIoQueue *queue, IO_STATUS_BLOCK *ioStatus, PVOID buffer, LARGE_INTEGER offset, ULONG length) { queue->LastReadOffset = offset; queue->LastReadLength = length; if (queue->ReadAheadBufferValid && queue->ReadAheadOffset.QuadPart == offset.QuadPart && queue->ReadAheadLength >= length) { memcpy (buffer, queue->ReadAheadBuffer, length); if (!queue->IsFilterDevice) { ioStatus->Information = length; ioStatus->Status = STATUS_SUCCESS; } return STATUS_SUCCESS; } if (queue->IsFilterDevice) return TCReadDevice (queue->LowerDeviceObject, buffer, offset, length); return ZwReadFile (queue->HostFileHandle, NULL, NULL, NULL, ioStatus, buffer, length, &offset, NULL); } static VOID IoThreadProc (PVOID threadArg) { EncryptedIoQueue *queue = (EncryptedIoQueue *) threadArg; PLIST_ENTRY listEntry; EncryptedIoRequest *request; KeSetPriorityThread (KeGetCurrentThread(), LOW_REALTIME_PRIORITY); if (!queue->IsFilterDevice && queue->SecurityClientContext) { #ifdef DEBUG NTSTATUS status = #endif SeImpersonateClientEx (queue->SecurityClientContext, NULL); ASSERT (NT_SUCCESS (status)); } while (!queue->ThreadExitRequested) { if (!NT_SUCCESS (KeWaitForSingleObject (&queue->IoThreadQueueNotEmptyEvent, Executive, KernelMode, FALSE, NULL))) continue; if (queue->ThreadExitRequested) break; while ((listEntry = ExInterlockedRemoveHeadList (&queue->IoThreadQueue, &queue->IoThreadQueueLock))) { InterlockedDecrement (&queue->IoThreadPendingRequestCount); request = CONTAINING_RECORD (listEntry, EncryptedIoRequest, ListEntry); #ifdef TC_TRACE_IO_QUEUE Dump ("%c %I64d [%I64d] roff=%I64d rlen=%d\n", request->Item->Write ? 'W' : 'R', request->Item->OriginalIrpOffset.QuadPart, GetElapsedTime (&queue->LastPerformanceCounter), request->Offset.QuadPart, request->Length); #endif // Perform IO request if no preceding request of the item failed if (NT_SUCCESS (request->Item->Status)) { if (queue->IsFilterDevice) { if (queue->RemapEncryptedArea && request->EncryptedLength > 0) { if (request->EncryptedLength != request->Length) { // Up to three subfragments may be required to handle a partially remapped fragment int subFragment; byte *subFragmentData = request->Data; for (subFragment = 0 ; subFragment < 3; ++subFragment) { LARGE_INTEGER subFragmentOffset; ULONG subFragmentLength; subFragmentOffset.QuadPart = request->Offset.QuadPart; switch (subFragment) { case 0: subFragmentLength = (ULONG) request->EncryptedOffset; break; case 1: subFragmentOffset.QuadPart += request->EncryptedOffset + queue->RemappedAreaOffset; subFragmentLength = request->EncryptedLength; break; case 2: subFragmentOffset.QuadPart += request->EncryptedOffset + request->EncryptedLength; subFragmentLength = (ULONG) (request->Length - (request->EncryptedOffset + request->EncryptedLength)); break; } if (subFragmentLength > 0) { if (request->Item->Write) request->Item->Status = TCWriteDevice (queue->LowerDeviceObject, subFragmentData, subFragmentOffset, subFragmentLength); else request->Item->Status = TCCachedRead (queue, NULL, subFragmentData, subFragmentOffset, subFragmentLength); subFragmentData += subFragmentLength; } } } else { // Remap the fragment LARGE_INTEGER remappedOffset; remappedOffset.QuadPart = request->Offset.QuadPart + queue->RemappedAreaOffset; if (request->Item->Write) request->Item->Status = TCWriteDevice (queue->LowerDeviceObject, request->Data, remappedOffset, request->Length); else request->Item->Status = TCCachedRead (queue, NULL, request->Data, remappedOffset, request->Length); } } else { if (request->Item->Write) request->Item->Status = TCWriteDevice (queue->LowerDeviceObject, request->Data, request->Offset, request->Length); else request->Item->Status = TCCachedRead (queue, NULL, request->Data, request->Offset, request->Length); } } else { IO_STATUS_BLOCK ioStatus; if (request->Item->Write) request->Item->Status = ZwWriteFile (queue->HostFileHandle, NULL, NULL, NULL, &ioStatus, request->Data, request->Length, &request->Offset, NULL); else request->Item->Status = TCCachedRead (queue, &ioStatus, request->Data, request->Offset, request->Length); if (NT_SUCCESS (request->Item->Status) && ioStatus.Information != request->Length) request->Item->Status = STATUS_END_OF_FILE; } } if (request->Item->Write) { queue->ReadAheadBufferValid = FALSE; ReleaseFragmentBuffer (queue, request->Data); if (request->CompleteOriginalIrp) { CompleteOriginalIrp (request->Item, request->Item->Status, NT_SUCCESS (request->Item->Status) ? request->Item->OriginalLength : 0); } ReleasePoolBuffer (queue, request); } else { BOOL readAhead = FALSE; if (NT_SUCCESS (request->Item->Status)) memcpy (request->OrigDataBufferFragment, request->Data, request->Length); ReleaseFragmentBuffer (queue, request->Data); request->Data = request->OrigDataBufferFragment; if (request->CompleteOriginalIrp && queue->LastReadLength > 0 && NT_SUCCESS (request->Item->Status) && InterlockedExchangeAdd (&queue->IoThreadPendingRequestCount, 0) == 0) { readAhead = TRUE; InterlockedIncrement (&queue->OutstandingIoCount); } ExInterlockedInsertTailList (&queue->CompletionThreadQueue, &request->CompletionListEntry, &queue->CompletionThreadQueueLock); KeSetEvent (&queue->CompletionThreadQueueNotEmptyEvent, IO_DISK_INCREMENT, FALSE); if (readAhead) { queue->ReadAheadBufferValid = FALSE; queue->ReadAheadOffset.QuadPart = queue->LastReadOffset.QuadPart + queue->LastReadLength; queue->ReadAheadLength = queue->LastReadLength; if (queue->ReadAheadOffset.QuadPart + queue->ReadAheadLength <= queue->MaxReadAheadOffset.QuadPart) { #ifdef TC_TRACE_IO_QUEUE Dump ("A %I64d [%I64d] roff=%I64d rlen=%d\n", request->Item->OriginalIrpOffset.QuadPart, GetElapsedTime (&queue->LastPerformanceCounter), queue->ReadAheadOffset, queue->ReadAheadLength); #endif if (queue->IsFilterDevice) { queue->ReadAheadBufferValid = NT_SUCCESS (TCReadDevice (queue->LowerDeviceObject, queue->ReadAheadBuffer, queue->ReadAheadOffset, queue->ReadAheadLength)); } else { IO_STATUS_BLOCK ioStatus; queue->ReadAheadBufferValid = NT_SUCCESS (ZwReadFile (queue->HostFileHandle, NULL, NULL, NULL, &ioStatus, queue->ReadAheadBuffer, queue->ReadAheadLength, &queue->ReadAheadOffset, NULL)); queue->ReadAheadLength = (ULONG) ioStatus.Information; } } DecrementOutstandingIoCount (queue); } } } } PsTerminateSystemThread (STATUS_SUCCESS); } static VOID MainThreadProc (PVOID threadArg) { EncryptedIoQueue *queue = (EncryptedIoQueue *) threadArg; PLIST_ENTRY listEntry; EncryptedIoQueueItem *item; LARGE_INTEGER fragmentOffset; ULONG dataRemaining; PUCHAR activeFragmentBuffer = queue->FragmentBufferA; PUCHAR dataBuffer; EncryptedIoRequest *request; uint64 intersectStart; uint32 intersectLength; ULONGLONG addResult; HRESULT hResult; if (IsEncryptionThreadPoolRunning()) KeSetPriorityThread (KeGetCurrentThread(), LOW_REALTIME_PRIORITY); while (!queue->ThreadExitRequested) { if (!NT_SUCCESS (KeWaitForSingleObject (&queue->MainThreadQueueNotEmptyEvent, Executive, KernelMode, FALSE, NULL))) continue; while ((listEntry = ExInterlockedRemoveHeadList (&queue->MainThreadQueue, &queue->MainThreadQueueLock))) { PIRP irp = CONTAINING_RECORD (listEntry, IRP, Tail.Overlay.ListEntry); PIO_STACK_LOCATION irpSp = IoGetCurrentIrpStackLocation (irp); if (queue->Suspended) KeWaitForSingleObject (&queue->QueueResumedEvent, Executive, KernelMode, FALSE, NULL); item = GetPoolBuffer (queue, sizeof (EncryptedIoQueueItem)); if (!item) { TCCompleteDiskIrp (irp, STATUS_INSUFFICIENT_RESOURCES, 0); DecrementOutstandingIoCount (queue); IoReleaseRemoveLock (&queue->RemoveLock, irp); continue; } item->Queue = queue; item->OriginalIrp = irp; item->Status = STATUS_SUCCESS; IoSetCancelRoutine (irp, NULL); if (irp->Cancel) { CompleteOriginalIrp (item, STATUS_CANCELLED, 0); continue; } switch (irpSp->MajorFunction) { case IRP_MJ_READ: item->Write = FALSE; item->OriginalOffset = irpSp->Parameters.Read.ByteOffset; item->OriginalLength = irpSp->Parameters.Read.Length; break; case IRP_MJ_WRITE: item->Write = TRUE; item->OriginalOffset = irpSp->Parameters.Write.ByteOffset; item->OriginalLength = irpSp->Parameters.Write.Length; break; default: CompleteOriginalIrp (item, STATUS_INVALID_PARAMETER, 0); continue; } #ifdef TC_TRACE_IO_QUEUE item->OriginalIrpOffset = item->OriginalOffset; #endif // Handle misaligned read operations to work around a bug in Windows System Assessment Tool which does not follow FILE_FLAG_NO_BUFFERING requirements when benchmarking disk devices if (queue->IsFilterDevice && !item->Write && item->OriginalLength > 0 && (item->OriginalLength & (ENCRYPTION_DATA_UNIT_SIZE - 1)) == 0 && (item->OriginalOffset.QuadPart & (ENCRYPTION_DATA_UNIT_SIZE - 1)) != 0) { byte *buffer; ULONG alignedLength; LARGE_INTEGER alignedOffset; hResult = ULongAdd(item->OriginalLength, ENCRYPTION_DATA_UNIT_SIZE, &alignedLength); if (hResult != S_OK) { CompleteOriginalIrp (item, STATUS_INVALID_PARAMETER, 0); continue; } alignedOffset.QuadPart = item->OriginalOffset.QuadPart & ~((LONGLONG) ENCRYPTION_DATA_UNIT_SIZE - 1); buffer = TCalloc (alignedLength); if (!buffer) { CompleteOriginalIrp (item, STATUS_INSUFFICIENT_RESOURCES, 0); continue; } item->Status = TCReadDevice (queue->LowerDeviceObject, buffer, alignedOffset, alignedLength); if (NT_SUCCESS (item->Status)) { UINT64_STRUCT dataUnit; dataBuffer = (PUCHAR) MmGetSystemAddressForMdlSafe (irp->MdlAddress, HighPagePriority); if (!dataBuffer) { TCfree (buffer); CompleteOriginalIrp (item, STATUS_INSUFFICIENT_RESOURCES, 0); continue; } if (queue->EncryptedAreaStart != -1 && queue->EncryptedAreaEnd != -1) { GetIntersection (alignedOffset.QuadPart, alignedLength, queue->EncryptedAreaStart, queue->EncryptedAreaEnd, &intersectStart, &intersectLength); if (intersectLength > 0) { dataUnit.Value = intersectStart / ENCRYPTION_DATA_UNIT_SIZE; DecryptDataUnits (buffer + (intersectStart - alignedOffset.QuadPart), &dataUnit, intersectLength / ENCRYPTION_DATA_UNIT_SIZE, queue->CryptoInfo); } } memcpy (dataBuffer, buffer + (item->OriginalOffset.LowPart & (ENCRYPTION_DATA_UNIT_SIZE - 1)), item->OriginalLength); } TCfree (buffer); CompleteOriginalIrp (item, item->Status, NT_SUCCESS (item->Status) ? item->OriginalLength : 0); continue; } // Validate offset and length if (item->OriginalLength == 0 || (item->OriginalLength & (ENCRYPTION_DATA_UNIT_SIZE - 1)) != 0 || (item->OriginalOffset.QuadPart & (ENCRYPTION_DATA_UNIT_SIZE - 1)) != 0 || ( !queue->IsFilterDevice && ( (S_OK != ULongLongAdd(item->OriginalOffset.QuadPart, item->OriginalLength, &addResult)) || (addResult > (ULONGLONG) queue->VirtualDeviceLength) ) ) ) { CompleteOriginalIrp (item, STATUS_INVALID_PARAMETER, 0); continue; } #ifdef TC_TRACE_IO_QUEUE Dump ("Q %I64d [%I64d] %c len=%d\n", item->OriginalOffset.QuadPart, GetElapsedTime (&queue->LastPerformanceCounter), item->Write ? 'W' : 'R', item->OriginalLength); #endif if (!queue->IsFilterDevice) { // Adjust the offset for host file or device if (queue->CryptoInfo->hiddenVolume) hResult = ULongLongAdd(item->OriginalOffset.QuadPart, queue->CryptoInfo->hiddenVolumeOffset, &addResult); else hResult = ULongLongAdd(item->OriginalOffset.QuadPart, queue->CryptoInfo->volDataAreaOffset, &addResult); if (hResult != S_OK) { CompleteOriginalIrp (item, STATUS_INVALID_PARAMETER, 0); continue; } else item->OriginalOffset.QuadPart = addResult; // Hidden volume protection if (item->Write && queue->CryptoInfo->bProtectHiddenVolume) { // If there has already been a write operation denied in order to protect the // hidden volume (since the volume mount time) if (queue->CryptoInfo->bHiddenVolProtectionAction) { // Do not allow writing to this volume anymore. This is to fake a complete volume // or system failure (otherwise certain kinds of inconsistency within the file // system could indicate that this volume has used hidden volume protection). CompleteOriginalIrp (item, STATUS_INVALID_PARAMETER, 0); continue; } // Verify that no byte is going to be written to the hidden volume area if (RegionsOverlap ((unsigned __int64) item->OriginalOffset.QuadPart, (unsigned __int64) item->OriginalOffset.QuadPart + item->OriginalLength - 1, queue->CryptoInfo->hiddenVolumeOffset, (unsigned __int64) queue->CryptoInfo->hiddenVolumeOffset + queue->CryptoInfo->hiddenVolumeProtectedSize - 1)) { Dump ("Hidden volume protection triggered: write %I64d-%I64d (protected %I64d-%I64d)\n", item->OriginalOffset.QuadPart, item->OriginalOffset.QuadPart + item->OriginalLength - 1, queue->CryptoInfo->hiddenVolumeOffset, queue->CryptoInfo->hiddenVolumeOffset + queue->CryptoInfo->hiddenVolumeProtectedSize - 1); queue->CryptoInfo->bHiddenVolProtectionAction = TRUE; // Deny this write operation to prevent the hidden volume from being overwritten CompleteOriginalIrp (item, STATUS_INVALID_PARAMETER, 0); continue; } } } else if (item->Write && RegionsOverlap (item->OriginalOffset.QuadPart, item->OriginalOffset.QuadPart + item->OriginalLength - 1, TC_BOOT_VOLUME_HEADER_SECTOR_OFFSET, TC_BOOT_VOLUME_HEADER_SECTOR_OFFSET + TC_BOOT_ENCRYPTION_VOLUME_HEADER_SIZE - 1)) { // Prevent inappropriately designed software from damaging important data that may be out of sync with the backup on the Rescue Disk (such as the end of the encrypted area). Dump ("Preventing write to the system encryption key data area\n"); CompleteOriginalIrp (item, STATUS_MEDIA_WRITE_PROTECTED, 0); continue; } else if (item->Write && IsHiddenSystemRunning() && (RegionsOverlap (item->OriginalOffset.QuadPart, item->OriginalOffset.QuadPart + item->OriginalLength - 1, TC_SECTOR_SIZE_BIOS, TC_BOOT_LOADER_AREA_SECTOR_COUNT * TC_SECTOR_SIZE_BIOS - 1) || RegionsOverlap (item->OriginalOffset.QuadPart, item->OriginalOffset.QuadPart + item->OriginalLength - 1, GetBootDriveLength(), _I64_MAX))) { Dump ("Preventing write to boot loader or host protected area\n"); CompleteOriginalIrp (item, STATUS_MEDIA_WRITE_PROTECTED, 0); continue; } dataBuffer = (PUCHAR) MmGetSystemAddressForMdlSafe (irp->MdlAddress, HighPagePriority); if (dataBuffer == NULL) { CompleteOriginalIrp (item, STATUS_INSUFFICIENT_RESOURCES, 0); continue; } // Divide data block to fragments to enable efficient overlapping of encryption and IO operations dataRemaining = item->OriginalLength; fragmentOffset = item->OriginalOffset; while (dataRemaining > 0) { BOOL isLastFragment = dataRemaining <= TC_ENC_IO_QUEUE_MAX_FRAGMENT_SIZE; ULONG dataFragmentLength = isLastFragment ? dataRemaining : TC_ENC_IO_QUEUE_MAX_FRAGMENT_SIZE; activeFragmentBuffer = (activeFragmentBuffer == queue->FragmentBufferA ? queue->FragmentBufferB : queue->FragmentBufferA); InterlockedIncrement (&queue->IoThreadPendingRequestCount); // Create IO request request = GetPoolBuffer (queue, sizeof (EncryptedIoRequest)); if (!request) { CompleteOriginalIrp (item, STATUS_INSUFFICIENT_RESOURCES, 0); break; } request->Item = item; request->CompleteOriginalIrp = isLastFragment; request->Offset = fragmentOffset; request->Data = activeFragmentBuffer; request->OrigDataBufferFragment = dataBuffer; request->Length = dataFragmentLength; if (queue->IsFilterDevice) { if (queue->EncryptedAreaStart == -1 || queue->EncryptedAreaEnd == -1) { request->EncryptedLength = 0; } else { // Get intersection of data fragment with encrypted area GetIntersection (fragmentOffset.QuadPart, dataFragmentLength, queue->EncryptedAreaStart, queue->EncryptedAreaEnd, &intersectStart, &intersectLength); request->EncryptedOffset = intersectStart - fragmentOffset.QuadPart; request->EncryptedLength = intersectLength; } } else { request->EncryptedOffset = 0; request->EncryptedLength = dataFragmentLength; } AcquireFragmentBuffer (queue, activeFragmentBuffer); if (item->Write) { // Encrypt data memcpy (activeFragmentBuffer, dataBuffer, dataFragmentLength); if (request->EncryptedLength > 0) { UINT64_STRUCT dataUnit; ASSERT (request->EncryptedOffset + request->EncryptedLength <= request->Offset.QuadPart + request->Length); dataUnit.Value = (request->Offset.QuadPart + request->EncryptedOffset) / ENCRYPTION_DATA_UNIT_SIZE; if (queue->CryptoInfo->bPartitionInInactiveSysEncScope) dataUnit.Value += queue->CryptoInfo->FirstDataUnitNo.Value; else if (queue->RemapEncryptedArea) dataUnit.Value += queue->RemappedAreaDataUnitOffset; EncryptDataUnits (activeFragmentBuffer + request->EncryptedOffset, &dataUnit, request->EncryptedLength / ENCRYPTION_DATA_UNIT_SIZE, queue->CryptoInfo); } } // Queue IO request ExInterlockedInsertTailList (&queue->IoThreadQueue, &request->ListEntry, &queue->IoThreadQueueLock); KeSetEvent (&queue->IoThreadQueueNotEmptyEvent, IO_DISK_INCREMENT, FALSE); if (isLastFragment) break; dataRemaining -= TC_ENC_IO_QUEUE_MAX_FRAGMENT_SIZE; dataBuffer += TC_ENC_IO_QUEUE_MAX_FRAGMENT_SIZE; fragmentOffset.QuadPart += TC_ENC_IO_QUEUE_MAX_FRAGMENT_SIZE; } } } PsTerminateSystemThread (STATUS_SUCCESS); } NTSTATUS EncryptedIoQueueAddIrp (EncryptedIoQueue *queue, PIRP irp) { NTSTATUS status; InterlockedIncrement (&queue->OutstandingIoCount); if (queue->StopPending) { Dump ("STATUS_DEVICE_NOT_READY out=%d\n", queue->OutstandingIoCount); status = STATUS_DEVICE_NOT_READY; goto err; } status = IoAcquireRemoveLock (&queue->RemoveLock, irp); if (!NT_SUCCESS (status)) goto err; #ifdef TC_TRACE_IO_QUEUE { PIO_STACK_LOCATION irpSp = IoGetCurrentIrpStackLocation (irp); Dump ("* %I64d [%I64d] %c len=%d out=%d\n", irpSp->MajorFunction == IRP_MJ_WRITE ? irpSp->Parameters.Write.ByteOffset : irpSp->Parameters.Read.ByteOffset, GetElapsedTime (&queue->LastPerformanceCounter), irpSp->MajorFunction == IRP_MJ_WRITE ? 'W' : 'R', irpSp->MajorFunction == IRP_MJ_WRITE ? irpSp->Parameters.Write.Length : irpSp->Parameters.Read.Length, queue->OutstandingIoCount); } #endif IoMarkIrpPending (irp); ExInterlockedInsertTailList (&queue->MainThreadQueue, &irp->Tail.Overlay.ListEntry, &queue->MainThreadQueueLock); KeSetEvent (&queue->MainThreadQueueNotEmptyEvent, IO_DISK_INCREMENT, FALSE); return STATUS_PENDING; err: DecrementOutstandingIoCount (queue); return status; } NTSTATUS EncryptedIoQueueHoldWhenIdle (EncryptedIoQueue *queue, int64 timeout) { NTSTATUS status; ASSERT (!queue->Suspended); queue->SuspendPending = TRUE; while (TRUE) { while (InterlockedExchangeAdd (&queue->OutstandingIoCount, 0) > 0) { LARGE_INTEGER waitTimeout; waitTimeout.QuadPart = timeout * -10000; status = KeWaitForSingleObject (&queue->NoOutstandingIoEvent, Executive, KernelMode, FALSE, timeout != 0 ? &waitTimeout : NULL); if (status == STATUS_TIMEOUT) status = STATUS_UNSUCCESSFUL; if (!NT_SUCCESS (status)) { queue->SuspendPending = FALSE; return status; } TCSleep (1); if (InterlockedExchangeAdd (&queue->OutstandingIoCount, 0) > 0) { queue->SuspendPending = FALSE; return STATUS_UNSUCCESSFUL; } } KeClearEvent (&queue->QueueResumedEvent); queue->Suspended = TRUE; if (InterlockedExchangeAdd (&queue->OutstandingIoCount, 0) == 0) break; queue->Suspended = FALSE; KeSetEvent (&queue->QueueResumedEvent, IO_DISK_INCREMENT, FALSE); } queue->ReadAheadBufferValid = FALSE; queue->SuspendPending = FALSE; return STATUS_SUCCESS; } BOOL EncryptedIoQueueIsSuspended (EncryptedIoQueue *queue) { return queue->Suspended; } BOOL EncryptedIoQueueIsRunning (EncryptedIoQueue *queue) { return !queue->StopPending; } NTSTATUS EncryptedIoQueueResumeFromHold (EncryptedIoQueue *queue) { ASSERT (queue->Suspended); queue->Suspended = FALSE; KeSetEvent (&queue->QueueResumedEvent, IO_DISK_INCREMENT, FALSE); return STATUS_SUCCESS; } NTSTATUS EncryptedIoQueueStart (EncryptedIoQueue *queue) { NTSTATUS status; EncryptedIoQueueBuffer *buffer; int i; queue->StartPending = TRUE; queue->ThreadExitRequested = FALSE; queue->OutstandingIoCount = 0; queue->IoThreadPendingRequestCount = 0; queue->FirstPoolBuffer = NULL; KeInitializeMutex (&queue->BufferPoolMutex, 0); KeInitializeEvent (&queue->NoOutstandingIoEvent, SynchronizationEvent, FALSE); KeInitializeEvent (&queue->PoolBufferFreeEvent, SynchronizationEvent, FALSE); KeInitializeEvent (&queue->QueueResumedEvent, SynchronizationEvent, FALSE); queue->FragmentBufferA = TCalloc (TC_ENC_IO_QUEUE_MAX_FRAGMENT_SIZE); if (!queue->FragmentBufferA) goto noMemory; queue->FragmentBufferB = TCalloc (TC_ENC_IO_QUEUE_MAX_FRAGMENT_SIZE); if (!queue->FragmentBufferB) goto noMemory; KeInitializeEvent (&queue->FragmentBufferAFreeEvent, SynchronizationEvent, TRUE); KeInitializeEvent (&queue->FragmentBufferBFreeEvent, SynchronizationEvent, TRUE); queue->ReadAheadBufferValid = FALSE; queue->ReadAheadBuffer = TCalloc (TC_ENC_IO_QUEUE_MAX_FRAGMENT_SIZE); if (!queue->ReadAheadBuffer) goto noMemory; // Preallocate buffers for (i = 0; i < TC_ENC_IO_QUEUE_PREALLOCATED_IO_REQUEST_COUNT; ++i) { if (i < TC_ENC_IO_QUEUE_PREALLOCATED_ITEM_COUNT && !GetPoolBuffer (queue, sizeof (EncryptedIoQueueItem))) goto noMemory; if (!GetPoolBuffer (queue, sizeof (EncryptedIoRequest))) goto noMemory; } for (buffer = queue->FirstPoolBuffer; buffer != NULL; buffer = buffer->NextBuffer) { buffer->InUse = FALSE; } // Main thread InitializeListHead (&queue->MainThreadQueue); KeInitializeSpinLock (&queue->MainThreadQueueLock); KeInitializeEvent (&queue->MainThreadQueueNotEmptyEvent, SynchronizationEvent, FALSE); status = TCStartThread (MainThreadProc, queue, &queue->MainThread); if (!NT_SUCCESS (status)) goto err; // IO thread InitializeListHead (&queue->IoThreadQueue); KeInitializeSpinLock (&queue->IoThreadQueueLock); KeInitializeEvent (&queue->IoThreadQueueNotEmptyEvent, SynchronizationEvent, FALSE); status = TCStartThread (IoThreadProc, queue, &queue->IoThread); if (!NT_SUCCESS (status)) { queue->ThreadExitRequested = TRUE; TCStopThread (queue->MainThread, &queue->MainThreadQueueNotEmptyEvent); goto err; } // Completion thread InitializeListHead (&queue->CompletionThreadQueue); KeInitializeSpinLock (&queue->CompletionThreadQueueLock); KeInitializeEvent (&queue->CompletionThreadQueueNotEmptyEvent, SynchronizationEvent, FALSE); status = TCStartThread (CompletionThreadProc, queue, &queue->CompletionThread); if (!NT_SUCCESS (status)) { queue->ThreadExitRequested = TRUE; TCStopThread (queue->MainThread, &queue->MainThreadQueueNotEmptyEvent); TCStopThread (queue->IoThread, &queue->IoThreadQueueNotEmptyEvent); goto err; } #ifdef TC_TRACE_IO_QUEUE GetElapsedTimeInit (&queue->LastPerformanceCounter); #endif queue->StopPending = FALSE; queue->StartPending = FALSE; Dump ("Queue started\n"); return STATUS_SUCCESS; noMemory: status = STATUS_INSUFFICIENT_RESOURCES; err: if (queue->FragmentBufferA) TCfree (queue->FragmentBufferA); if (queue->FragmentBufferB) TCfree (queue->FragmentBufferB); if (queue->ReadAheadBuffer) TCfree (queue->ReadAheadBuffer); FreePoolBuffers (queue); queue->StartPending = FALSE; return status; } NTSTATUS EncryptedIoQueueStop (EncryptedIoQueue *queue) { ASSERT (!queue->StopPending); queue->StopPending = TRUE; while (InterlockedExchangeAdd (&queue->OutstandingIoCount, 0) > 0) { KeWaitForSingleObject (&queue->NoOutstandingIoEvent, Executive, KernelMode, FALSE, NULL); } Dump ("Queue stopping out=%d\n", queue->OutstandingIoCount); queue->ThreadExitRequested = TRUE; TCStopThread (queue->MainThread, &queue->MainThreadQueueNotEmptyEvent); TCStopThread (queue->IoThread, &queue->IoThreadQueueNotEmptyEvent); TCStopThread (queue->CompletionThread, &queue->CompletionThreadQueueNotEmptyEvent); TCfree (queue->FragmentBufferA); TCfree (queue->FragmentBufferB); TCfree (queue->ReadAheadBuffer); FreePoolBuffers (queue); Dump ("Queue stopped out=%d\n", queue->OutstandingIoCount); return STATUS_SUCCESS; }