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file.c
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file.c
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/**
* @file sys/file.c
*
* @copyright 2015-2020 Bill Zissimopoulos
*/
/*
* This file is part of WinFsp.
*
* You can redistribute it and/or modify it under the terms of the GNU
* General Public License version 3 as published by the Free Software
* Foundation.
*
* Licensees holding a valid commercial license may use this software
* in accordance with the commercial license agreement provided in
* conjunction with the software. The terms and conditions of any such
* commercial license agreement shall govern, supersede, and render
* ineffective any application of the GPLv3 license to this software,
* notwithstanding of any reference thereto in the software or
* associated repository.
*/
#include <sys/driver.h>
NTSTATUS FspFileNodeCopyActiveList(PDEVICE_OBJECT DeviceObject,
FSP_FILE_NODE ***PFileNodes, PULONG PFileNodeCount);
NTSTATUS FspFileNodeCopyOpenList(PDEVICE_OBJECT DeviceObject,
FSP_FILE_NODE ***PFileNodes, PULONG PFileNodeCount);
VOID FspFileNodeDeleteList(FSP_FILE_NODE **FileNodes, ULONG FileNodeCount);
NTSTATUS FspFileNodeCreate(PDEVICE_OBJECT DeviceObject,
ULONG ExtraSize, FSP_FILE_NODE **PFileNode);
VOID FspFileNodeDelete(FSP_FILE_NODE *FileNode);
VOID FspFileNodeAcquireSharedF(FSP_FILE_NODE *FileNode, ULONG Flags);
BOOLEAN FspFileNodeTryAcquireSharedF(FSP_FILE_NODE *FileNode, ULONG Flags, BOOLEAN Wait);
VOID FspFileNodeAcquireExclusiveF(FSP_FILE_NODE *FileNode, ULONG Flags);
BOOLEAN FspFileNodeTryAcquireExclusiveF(FSP_FILE_NODE *FileNode, ULONG Flags, BOOLEAN Wait);
VOID FspFileNodeConvertExclusiveToSharedF(FSP_FILE_NODE *FileNode, ULONG Flags);
VOID FspFileNodeSetOwnerF(FSP_FILE_NODE *FileNode, ULONG Flags, PVOID Owner);
VOID FspFileNodeReleaseF(FSP_FILE_NODE *FileNode, ULONG Flags);
VOID FspFileNodeReleaseOwnerF(FSP_FILE_NODE *FileNode, ULONG Flags, PVOID Owner);
NTSTATUS FspFileNodeOpen(FSP_FILE_NODE *FileNode, PFILE_OBJECT FileObject,
UINT32 GrantedAccess, UINT32 ShareAccess,
FSP_FILE_NODE **POpenedFileNode, PULONG PSharingViolationReason);
VOID FspFileNodeCleanup(FSP_FILE_NODE *FileNode, PFILE_OBJECT FileObject, PULONG PCleanupFlags);
VOID FspFileNodeCleanupFlush(FSP_FILE_NODE *FileNode, PFILE_OBJECT FileObject);
VOID FspFileNodeCleanupComplete(FSP_FILE_NODE *FileNode, PFILE_OBJECT FileObject);
VOID FspFileNodeClose(FSP_FILE_NODE *FileNode,
PFILE_OBJECT FileObject, /* non-0 to remove share access */
BOOLEAN HandleCleanup); /* TRUE to decrement handle count */
NTSTATUS FspFileNodeFlushAndPurgeCache(FSP_FILE_NODE *FileNode,
UINT64 FlushOffset64, ULONG FlushLength, BOOLEAN FlushAndPurge);
VOID FspFileNodeOverwriteStreams(FSP_FILE_NODE *FileNode);
NTSTATUS FspFileNodeCheckBatchOplocksOnAllStreams(
PDEVICE_OBJECT FsvolDeviceObject,
PIRP OplockIrp,
FSP_FILE_NODE *FileNode,
ULONG AcquireFlags,
PUNICODE_STRING StreamFileName);
NTSTATUS FspFileNodeRenameCheck(PDEVICE_OBJECT FsvolDeviceObject, PIRP OplockIrp,
FSP_FILE_NODE *FileNode, ULONG AcquireFlags,
PUNICODE_STRING FileName, BOOLEAN CheckingOldName);
VOID FspFileNodeRename(FSP_FILE_NODE *FileNode, PUNICODE_STRING NewFileName);
VOID FspFileNodeGetFileInfo(FSP_FILE_NODE *FileNode, FSP_FSCTL_FILE_INFO *FileInfo);
BOOLEAN FspFileNodeTryGetFileInfo(FSP_FILE_NODE *FileNode, FSP_FSCTL_FILE_INFO *FileInfo);
BOOLEAN FspFileNodeTryGetFileInfoByName(PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp,
PUNICODE_STRING FileName, FSP_FSCTL_FILE_INFO *FileInfo);
VOID FspFileNodeSetFileInfo(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
const FSP_FSCTL_FILE_INFO *FileInfo, BOOLEAN TruncateOnClose);
BOOLEAN FspFileNodeTrySetFileInfoAndSecurityOnOpen(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
const FSP_FSCTL_FILE_INFO *FileInfo,
const PSECURITY_DESCRIPTOR SecurityDescriptor, ULONG SecurityDescriptorSize,
BOOLEAN TruncateOnClose);
BOOLEAN FspFileNodeTrySetFileInfo(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
const FSP_FSCTL_FILE_INFO *FileInfo, ULONG InfoChangeNumber);
VOID FspFileNodeInvalidateFileInfo(FSP_FILE_NODE *FileNode);
BOOLEAN FspFileNodeReferenceSecurity(FSP_FILE_NODE *FileNode, PCVOID *PBuffer, PULONG PSize);
VOID FspFileNodeSetSecurity(FSP_FILE_NODE *FileNode, PCVOID Buffer, ULONG Size);
BOOLEAN FspFileNodeTrySetSecurity(FSP_FILE_NODE *FileNode, PCVOID Buffer, ULONG Size,
ULONG SecurityChangeNumber);
VOID FspFileNodeInvalidateSecurity(FSP_FILE_NODE *FileNode);
BOOLEAN FspFileNodeReferenceDirInfo(FSP_FILE_NODE *FileNode, PCVOID *PBuffer, PULONG PSize);
VOID FspFileNodeSetDirInfo(FSP_FILE_NODE *FileNode, PCVOID Buffer, ULONG Size);
BOOLEAN FspFileNodeTrySetDirInfo(FSP_FILE_NODE *FileNode, PCVOID Buffer, ULONG Size,
ULONG DirInfoChangeNumber);
static VOID FspFileNodeInvalidateDirInfo(FSP_FILE_NODE *FileNode);
static VOID FspFileNodeInvalidateDirInfoByName(PDEVICE_OBJECT FsvolDeviceObject,
PUNICODE_STRING FileName);
VOID FspFileNodeInvalidateParentDirInfo(FSP_FILE_NODE *FileNode);
BOOLEAN FspFileNodeReferenceStreamInfo(FSP_FILE_NODE *FileNode, PCVOID *PBuffer, PULONG PSize);
VOID FspFileNodeSetStreamInfo(FSP_FILE_NODE *FileNode, PCVOID Buffer, ULONG Size);
BOOLEAN FspFileNodeTrySetStreamInfo(FSP_FILE_NODE *FileNode, PCVOID Buffer, ULONG Size,
ULONG StreamInfoChangeNumber);
VOID FspFileNodeInvalidateStreamInfo(FSP_FILE_NODE *FileNode);
BOOLEAN FspFileNodeReferenceEa(FSP_FILE_NODE *FileNode, PCVOID *PBuffer, PULONG PSize);
VOID FspFileNodeSetEa(FSP_FILE_NODE *FileNode, PCVOID Buffer, ULONG Size);
BOOLEAN FspFileNodeTrySetEa(FSP_FILE_NODE *FileNode, PCVOID Buffer, ULONG Size,
ULONG EaChangeNumber);
VOID FspFileNodeInvalidateEa(FSP_FILE_NODE *FileNode);
VOID FspFileNodeNotifyChange(FSP_FILE_NODE *FileNode, ULONG Filter, ULONG Action,
BOOLEAN InvalidateCaches);
VOID FspFileNodeInvalidateCachesAndNotifyChangeByName(PDEVICE_OBJECT FsvolDeviceObject,
PUNICODE_STRING FileName, ULONG Filter, ULONG Action,
BOOLEAN InvalidateParentCaches);
NTSTATUS FspFileNodeProcessLockIrp(FSP_FILE_NODE *FileNode, PIRP Irp);
static NTSTATUS FspFileNodeCompleteLockIrp(PVOID Context, PIRP Irp);
NTSTATUS FspFileDescCreate(FSP_FILE_DESC **PFileDesc);
VOID FspFileDescDelete(FSP_FILE_DESC *FileDesc);
NTSTATUS FspFileDescResetDirectory(FSP_FILE_DESC *FileDesc,
PUNICODE_STRING FileName, BOOLEAN RestartScan, BOOLEAN IndexSpecified);
NTSTATUS FspFileDescSetDirectoryMarker(FSP_FILE_DESC *FileDesc,
PUNICODE_STRING FileName);
NTSTATUS FspMainFileOpen(
PDEVICE_OBJECT FsvolDeviceObject,
PDEVICE_OBJECT DeviceObjectHint,
PUNICODE_STRING MainFileName, BOOLEAN CaseSensitive,
PSECURITY_DESCRIPTOR SecurityDescriptor,
ULONG FileAttributes,
ULONG Disposition,
PHANDLE PMainFileHandle,
PFILE_OBJECT *PMainFileObject);
NTSTATUS FspMainFileClose(
HANDLE MainFileHandle,
PFILE_OBJECT MainFileObject);
VOID FspFileNodeOplockPrepare(PVOID Context, PIRP Irp);
VOID FspFileNodeOplockComplete(PVOID Context, PIRP Irp);
#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE, FspFileNodeCopyActiveList)
#pragma alloc_text(PAGE, FspFileNodeCopyOpenList)
#pragma alloc_text(PAGE, FspFileNodeDeleteList)
#pragma alloc_text(PAGE, FspFileNodeCreate)
#pragma alloc_text(PAGE, FspFileNodeDelete)
#pragma alloc_text(PAGE, FspFileNodeAcquireSharedF)
#pragma alloc_text(PAGE, FspFileNodeTryAcquireSharedF)
#pragma alloc_text(PAGE, FspFileNodeAcquireExclusiveF)
#pragma alloc_text(PAGE, FspFileNodeTryAcquireExclusiveF)
#pragma alloc_text(PAGE, FspFileNodeConvertExclusiveToSharedF)
#pragma alloc_text(PAGE, FspFileNodeSetOwnerF)
#pragma alloc_text(PAGE, FspFileNodeReleaseF)
#pragma alloc_text(PAGE, FspFileNodeReleaseOwnerF)
#pragma alloc_text(PAGE, FspFileNodeOpen)
#pragma alloc_text(PAGE, FspFileNodeCleanup)
#pragma alloc_text(PAGE, FspFileNodeCleanupFlush)
#pragma alloc_text(PAGE, FspFileNodeCleanupComplete)
#pragma alloc_text(PAGE, FspFileNodeClose)
#pragma alloc_text(PAGE, FspFileNodeFlushAndPurgeCache)
#pragma alloc_text(PAGE, FspFileNodeOverwriteStreams)
#pragma alloc_text(PAGE, FspFileNodeCheckBatchOplocksOnAllStreams)
#pragma alloc_text(PAGE, FspFileNodeRenameCheck)
#pragma alloc_text(PAGE, FspFileNodeRename)
#pragma alloc_text(PAGE, FspFileNodeGetFileInfo)
#pragma alloc_text(PAGE, FspFileNodeTryGetFileInfo)
#pragma alloc_text(PAGE, FspFileNodeTryGetFileInfoByName)
#pragma alloc_text(PAGE, FspFileNodeSetFileInfo)
#pragma alloc_text(PAGE, FspFileNodeTrySetFileInfoAndSecurityOnOpen)
#pragma alloc_text(PAGE, FspFileNodeTrySetFileInfo)
#pragma alloc_text(PAGE, FspFileNodeInvalidateFileInfo)
// !#pragma alloc_text(PAGE, FspFileNodeReferenceSecurity)
// !#pragma alloc_text(PAGE, FspFileNodeSetSecurity)
// !#pragma alloc_text(PAGE, FspFileNodeTrySetSecurity)
// !#pragma alloc_text(PAGE, FspFileNodeInvalidateSecurity)
// !#pragma alloc_text(PAGE, FspFileNodeReferenceDirInfo)
// !#pragma alloc_text(PAGE, FspFileNodeSetDirInfo)
// !#pragma alloc_text(PAGE, FspFileNodeTrySetDirInfo)
// !#pragma alloc_text(PAGE, FspFileNodeInvalidateDirInfo)
#pragma alloc_text(PAGE, FspFileNodeInvalidateDirInfoByName)
#pragma alloc_text(PAGE, FspFileNodeInvalidateParentDirInfo)
// !#pragma alloc_text(PAGE, FspFileNodeReferenceStreamInfo)
// !#pragma alloc_text(PAGE, FspFileNodeSetStreamInfo)
// !#pragma alloc_text(PAGE, FspFileNodeTrySetStreamInfo)
// !#pragma alloc_text(PAGE, FspFileNodeInvalidateStreamInfo)
// !#pragma alloc_text(PAGE, FspFileNodeReferenceEa)
// !#pragma alloc_text(PAGE, FspFileNodeSetEa)
// !#pragma alloc_text(PAGE, FspFileNodeTrySetEa)
// !#pragma alloc_text(PAGE, FspFileNodeInvalidateEa)
#pragma alloc_text(PAGE, FspFileNodeNotifyChange)
#pragma alloc_text(PAGE, FspFileNodeInvalidateCachesAndNotifyChangeByName)
#pragma alloc_text(PAGE, FspFileNodeProcessLockIrp)
#pragma alloc_text(PAGE, FspFileNodeCompleteLockIrp)
#pragma alloc_text(PAGE, FspFileDescCreate)
#pragma alloc_text(PAGE, FspFileDescDelete)
#pragma alloc_text(PAGE, FspFileDescResetDirectory)
#pragma alloc_text(PAGE, FspFileDescSetDirectoryMarker)
#pragma alloc_text(PAGE, FspMainFileOpen)
#pragma alloc_text(PAGE, FspMainFileClose)
#pragma alloc_text(PAGE, FspFileNodeOplockPrepare)
#pragma alloc_text(PAGE, FspFileNodeOplockComplete)
#endif
#define FSP_FILE_NODE_GET_FLAGS() \
PIRP Irp = IoGetTopLevelIrp(); \
BOOLEAN IrpValid = (PIRP)FSRTL_MAX_TOP_LEVEL_IRP_FLAG < Irp &&\
IO_TYPE_IRP == Irp->Type; \
if (IrpValid) \
Flags &= ~FspIrpTopFlags(Irp)
#define FSP_FILE_NODE_ASSERT_FLAGS_CLR()\
ASSERT(IrpValid ? (0 == (FspIrpFlags(Irp) & Flags)) : TRUE)
#define FSP_FILE_NODE_ASSERT_FLAGS_SET()\
ASSERT(IrpValid ? (Flags == (FspIrpFlags(Irp) & Flags)) : TRUE)
#define FSP_FILE_NODE_SET_FLAGS() \
if (IrpValid) \
FspIrpSetFlags(Irp, FspIrpFlags(Irp) | Flags)
#define FSP_FILE_NODE_CLR_FLAGS() \
if (IrpValid) \
FspIrpSetFlags(Irp, FspIrpFlags(Irp) & (~Flags & 3))
#define GATHER_DESCENDANTS(FILENAME, REFERENCE, ...)\
FSP_FILE_NODE *DescendantFileNode;\
FSP_FILE_NODE *DescendantFileNodeArray[16], **DescendantFileNodes;\
ULONG DescendantFileNodeCount, DescendantFileNodeIndex;\
FSP_DEVICE_CONTEXT_BY_NAME_TABLE_RESTART_KEY RestartKey;\
DescendantFileNodes = DescendantFileNodeArray;\
DescendantFileNodeCount = 0;\
memset(&RestartKey, 0, sizeof RestartKey);\
for (;;) \
{ \
DescendantFileNode = FspFsvolDeviceEnumerateContextByName(FsvolDeviceObject,\
FILENAME, FALSE, &RestartKey);\
if (0 == DescendantFileNode) \
break; \
ASSERT(0 == ((UINT_PTR)DescendantFileNode & 7));\
__VA_ARGS__; \
if (REFERENCE) \
FspFileNodeReference((PVOID)((UINT_PTR)DescendantFileNode & ~7));\
if (ARRAYSIZE(DescendantFileNodeArray) > DescendantFileNodeCount)\
DescendantFileNodes[DescendantFileNodeCount] = DescendantFileNode;\
DescendantFileNodeCount++; \
} \
if (ARRAYSIZE(DescendantFileNodeArray) < DescendantFileNodeCount ||\
DEBUGTEST_EX(0 != DescendantFileNodeCount, 10, FALSE)) \
{ \
DescendantFileNodes = FspAllocMustSucceed(DescendantFileNodeCount * sizeof(FSP_FILE_NODE *));\
DescendantFileNodeIndex = 0; \
memset(&RestartKey, 0, sizeof RestartKey);\
for (;;) \
{ \
DescendantFileNode = FspFsvolDeviceEnumerateContextByName(FsvolDeviceObject,\
FILENAME, FALSE, &RestartKey);\
if (0 == DescendantFileNode)\
break; \
ASSERT(0 == ((UINT_PTR)DescendantFileNode & 7));\
__VA_ARGS__; \
DescendantFileNodes[DescendantFileNodeIndex] = DescendantFileNode;\
DescendantFileNodeIndex++; \
ASSERT(DescendantFileNodeCount >= DescendantFileNodeIndex);\
} \
ASSERT(DescendantFileNodeCount == DescendantFileNodeIndex);\
} \
((VOID)0)
#define SCATTER_DESCENDANTS(REFERENCE) \
if (REFERENCE) \
{ \
for ( \
DescendantFileNodeIndex = 0;\
DescendantFileNodeCount > DescendantFileNodeIndex;\
DescendantFileNodeIndex++) \
{ \
DescendantFileNode = DescendantFileNodes[DescendantFileNodeIndex];\
FspFileNodeDereference((PVOID)((UINT_PTR)DescendantFileNode & ~7));\
} \
} \
if (DescendantFileNodeArray != DescendantFileNodes)\
FspFree(DescendantFileNodes); \
((VOID)0)
NTSTATUS FspFileNodeCopyActiveList(PDEVICE_OBJECT DeviceObject,
FSP_FILE_NODE ***PFileNodes, PULONG PFileNodeCount)
{
PAGED_CODE();
NTSTATUS Result;
ULONG Index;
FspFsvolDeviceLockContextTable(DeviceObject);
Result = FspFsvolDeviceCopyContextList(DeviceObject, PFileNodes, PFileNodeCount);
if (NT_SUCCESS(Result))
{
for (Index = 0; *PFileNodeCount > Index; Index++)
FspFileNodeReference((*PFileNodes)[Index]);
}
FspFsvolDeviceUnlockContextTable(DeviceObject);
return Result;
}
NTSTATUS FspFileNodeCopyOpenList(PDEVICE_OBJECT DeviceObject,
FSP_FILE_NODE ***PFileNodes, PULONG PFileNodeCount)
{
PAGED_CODE();
NTSTATUS Result;
ULONG Index;
FspFsvolDeviceLockContextTable(DeviceObject);
Result = FspFsvolDeviceCopyContextByNameList(DeviceObject, PFileNodes, PFileNodeCount);
if (NT_SUCCESS(Result))
{
for (Index = 0; *PFileNodeCount > Index; Index++)
FspFileNodeReference((*PFileNodes)[Index]);
}
FspFsvolDeviceUnlockContextTable(DeviceObject);
return Result;
}
VOID FspFileNodeDeleteList(FSP_FILE_NODE **FileNodes, ULONG FileNodeCount)
{
PAGED_CODE();
ULONG Index;
for (Index = 0; FileNodeCount > Index; Index++)
FspFileNodeDereference(FileNodes[Index]);
FspFsvolDeviceDeleteContextList(FileNodes, FileNodeCount);
}
NTSTATUS FspFileNodeCreate(PDEVICE_OBJECT DeviceObject,
ULONG ExtraSize, FSP_FILE_NODE **PFileNode)
{
PAGED_CODE();
*PFileNode = 0;
FSP_FILE_NODE_NONPAGED *NonPaged = FspAllocNonPaged(sizeof *NonPaged);
if (0 == NonPaged)
return STATUS_INSUFFICIENT_RESOURCES;
FSP_FILE_NODE *FileNode = FspAlloc(sizeof *FileNode + ExtraSize);
if (0 == FileNode)
{
FspFree(NonPaged);
return STATUS_INSUFFICIENT_RESOURCES;
}
RtlZeroMemory(NonPaged, sizeof *NonPaged);
ExInitializeResourceLite(&NonPaged->Resource);
ExInitializeResourceLite(&NonPaged->PagingIoResource);
ExInitializeFastMutex(&NonPaged->HeaderFastMutex);
KeInitializeSpinLock(&NonPaged->NpInfoSpinLock);
RtlZeroMemory(FileNode, sizeof *FileNode + ExtraSize);
FileNode->Header.NodeTypeCode = FspFileNodeFileKind;
FileNode->Header.NodeByteSize = sizeof *FileNode;
FileNode->Header.IsFastIoPossible = FastIoIsNotPossible;
FileNode->Header.Resource = &NonPaged->Resource;
FileNode->Header.PagingIoResource = &NonPaged->PagingIoResource;
FileNode->Header.ValidDataLength.QuadPart = MAXLONGLONG;
/* disable ValidDataLength functionality */
FsRtlSetupAdvancedHeader(&FileNode->Header, &NonPaged->HeaderFastMutex);
FileNode->NonPaged = NonPaged;
FileNode->RefCount = 1;
FileNode->FsvolDeviceObject = DeviceObject;
FspDeviceReference(FileNode->FsvolDeviceObject);
RtlInitEmptyUnicodeString(&FileNode->FileName, FileNode->FileNameBuf, (USHORT)ExtraSize);
FsRtlInitializeFileLock(&FileNode->FileLock, FspFileNodeCompleteLockIrp, 0);
FsRtlInitializeOplock(FspFileNodeAddrOfOplock(FileNode));
*PFileNode = FileNode;
return STATUS_SUCCESS;
}
VOID FspFileNodeDelete(FSP_FILE_NODE *FileNode)
{
PAGED_CODE();
FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension =
FspFsvolDeviceExtension(FileNode->FsvolDeviceObject);
if (0 != FileNode->MainFileNode)
FspFileNodeDereference(FileNode->MainFileNode);
FsRtlUninitializeOplock(FspFileNodeAddrOfOplock(FileNode));
FsRtlUninitializeFileLock(&FileNode->FileLock);
FsRtlTeardownPerStreamContexts(&FileNode->Header);
FspMetaCacheInvalidateItem(FsvolDeviceExtension->EaCache, FileNode->NonPaged->Ea);
FspMetaCacheInvalidateItem(FsvolDeviceExtension->StreamInfoCache, FileNode->NonPaged->StreamInfo);
FspMetaCacheInvalidateItem(FsvolDeviceExtension->DirInfoCache, FileNode->NonPaged->DirInfo);
FspMetaCacheInvalidateItem(FsvolDeviceExtension->SecurityCache, FileNode->NonPaged->Security);
FspDeviceDereference(FileNode->FsvolDeviceObject);
if (0 != FileNode->ExternalFileName)
FspFree(FileNode->ExternalFileName);
ExDeleteResourceLite(&FileNode->NonPaged->PagingIoResource);
ExDeleteResourceLite(&FileNode->NonPaged->Resource);
FspFree(FileNode->NonPaged);
FspFree(FileNode);
}
VOID FspFileNodeAcquireSharedF(FSP_FILE_NODE *FileNode, ULONG Flags)
{
PAGED_CODE();
if (0 != FileNode->MainFileNode)
FileNode = FileNode->MainFileNode;
FSP_FILE_NODE_GET_FLAGS();
FSP_FILE_NODE_ASSERT_FLAGS_CLR();
if (Flags & FspFileNodeAcquireMain)
ExAcquireResourceSharedLite(FileNode->Header.Resource, TRUE);
if (Flags & FspFileNodeAcquirePgio)
ExAcquireResourceSharedLite(FileNode->Header.PagingIoResource, TRUE);
FSP_FILE_NODE_SET_FLAGS();
}
BOOLEAN FspFileNodeTryAcquireSharedF(FSP_FILE_NODE *FileNode, ULONG Flags, BOOLEAN Wait)
{
PAGED_CODE();
if (0 != FileNode->MainFileNode)
FileNode = FileNode->MainFileNode;
FSP_FILE_NODE_GET_FLAGS();
FSP_FILE_NODE_ASSERT_FLAGS_CLR();
BOOLEAN Result = TRUE;
if (Flags & FspFileNodeAcquireMain)
{
Result = ExAcquireResourceSharedLite(FileNode->Header.Resource, Wait);
if (!Result)
return FALSE;
}
if (Flags & FspFileNodeAcquirePgio)
{
Result = ExAcquireResourceSharedLite(FileNode->Header.PagingIoResource, Wait);
if (!Result)
{
if (Flags & FspFileNodeAcquireMain)
ExReleaseResourceLite(FileNode->Header.Resource);
return FALSE;
}
}
if (Result)
FSP_FILE_NODE_SET_FLAGS();
return Result;
}
VOID FspFileNodeAcquireExclusiveF(FSP_FILE_NODE *FileNode, ULONG Flags)
{
PAGED_CODE();
if (0 != FileNode->MainFileNode)
FileNode = FileNode->MainFileNode;
FSP_FILE_NODE_GET_FLAGS();
FSP_FILE_NODE_ASSERT_FLAGS_CLR();
if (Flags & FspFileNodeAcquireMain)
ExAcquireResourceExclusiveLite(FileNode->Header.Resource, TRUE);
if (Flags & FspFileNodeAcquirePgio)
ExAcquireResourceExclusiveLite(FileNode->Header.PagingIoResource, TRUE);
FSP_FILE_NODE_SET_FLAGS();
}
BOOLEAN FspFileNodeTryAcquireExclusiveF(FSP_FILE_NODE *FileNode, ULONG Flags, BOOLEAN Wait)
{
PAGED_CODE();
if (0 != FileNode->MainFileNode)
FileNode = FileNode->MainFileNode;
FSP_FILE_NODE_GET_FLAGS();
FSP_FILE_NODE_ASSERT_FLAGS_CLR();
BOOLEAN Result = TRUE;
if (Flags & FspFileNodeAcquireMain)
{
Result = ExAcquireResourceExclusiveLite(FileNode->Header.Resource, Wait);
if (!Result)
return FALSE;
}
if (Flags & FspFileNodeAcquirePgio)
{
Result = ExAcquireResourceExclusiveLite(FileNode->Header.PagingIoResource, Wait);
if (!Result)
{
if (Flags & FspFileNodeAcquireMain)
ExReleaseResourceLite(FileNode->Header.Resource);
return FALSE;
}
}
if (Result)
FSP_FILE_NODE_SET_FLAGS();
return Result;
}
VOID FspFileNodeConvertExclusiveToSharedF(FSP_FILE_NODE *FileNode, ULONG Flags)
{
PAGED_CODE();
if (0 != FileNode->MainFileNode)
FileNode = FileNode->MainFileNode;
FSP_FILE_NODE_GET_FLAGS();
if (Flags & FspFileNodeAcquirePgio)
ExConvertExclusiveToSharedLite(FileNode->Header.PagingIoResource);
if (Flags & FspFileNodeAcquireMain)
ExConvertExclusiveToSharedLite(FileNode->Header.Resource);
}
VOID FspFileNodeSetOwnerF(FSP_FILE_NODE *FileNode, ULONG Flags, PVOID Owner)
{
PAGED_CODE();
if (0 != FileNode->MainFileNode)
FileNode = FileNode->MainFileNode;
FSP_FILE_NODE_GET_FLAGS();
Owner = (PVOID)((UINT_PTR)Owner | 3);
if (Flags & FspFileNodeAcquireMain)
ExSetResourceOwnerPointer(FileNode->Header.Resource, Owner);
if (Flags & FspFileNodeAcquirePgio)
ExSetResourceOwnerPointer(FileNode->Header.PagingIoResource, Owner);
}
VOID FspFileNodeReleaseF(FSP_FILE_NODE *FileNode, ULONG Flags)
{
PAGED_CODE();
if (0 != FileNode->MainFileNode)
FileNode = FileNode->MainFileNode;
FSP_FILE_NODE_GET_FLAGS();
FSP_FILE_NODE_ASSERT_FLAGS_SET();
if (Flags & FspFileNodeAcquirePgio)
ExReleaseResourceLite(FileNode->Header.PagingIoResource);
if (Flags & FspFileNodeAcquireMain)
ExReleaseResourceLite(FileNode->Header.Resource);
FSP_FILE_NODE_CLR_FLAGS();
}
VOID FspFileNodeReleaseOwnerF(FSP_FILE_NODE *FileNode, ULONG Flags, PVOID Owner)
{
PAGED_CODE();
if (0 != FileNode->MainFileNode)
FileNode = FileNode->MainFileNode;
FSP_FILE_NODE_GET_FLAGS();
FSP_FILE_NODE_ASSERT_FLAGS_SET();
Owner = (PVOID)((UINT_PTR)Owner | 3);
if (Flags & FspFileNodeAcquirePgio)
{
if (ExIsResourceAcquiredLite(FileNode->Header.PagingIoResource))
ExReleaseResourceLite(FileNode->Header.PagingIoResource);
else
ExReleaseResourceForThreadLite(FileNode->Header.PagingIoResource, (ERESOURCE_THREAD)Owner);
}
if (Flags & FspFileNodeAcquireMain)
{
if (ExIsResourceAcquiredLite(FileNode->Header.Resource))
ExReleaseResourceLite(FileNode->Header.Resource);
else
ExReleaseResourceForThreadLite(FileNode->Header.Resource, (ERESOURCE_THREAD)Owner);
}
FSP_FILE_NODE_CLR_FLAGS();
}
NTSTATUS FspFileNodeOpen(FSP_FILE_NODE *FileNode, PFILE_OBJECT FileObject,
UINT32 GrantedAccess, UINT32 ShareAccess,
FSP_FILE_NODE **POpenedFileNode, PULONG PSharingViolationReason)
{
/*
* Attempt to insert our FileNode into the volume device's generic table.
* If an FileNode with the same UserContext already exists, then use that
* FileNode instead.
*
* There is no FileNode that can be acquired when calling this function.
*/
PAGED_CODE();
PDEVICE_OBJECT FsvolDeviceObject = FileNode->FsvolDeviceObject;
FSP_FILE_NODE *OpenedFileNode = 0;
BOOLEAN Inserted, DeletePending;
NTSTATUS Result;
*PSharingViolationReason = FspFileNodeSharingViolationGeneral;
FspFsvolDeviceLockContextTable(FsvolDeviceObject);
/*
* If this is a named stream we must also check with our main file.
* Note that FileNode->MainFileNode and OpenedFileNode->MainFileNode
* will always be the same.
*/
if (0 != FileNode->MainFileNode)
{
DeletePending = 0 != FileNode->MainFileNode->DeletePending;
MemoryBarrier();
if (DeletePending)
{
Result = STATUS_DELETE_PENDING;
goto exit;
}
/*
* Sharing violations between main file and streams were determined
* through experimentation with NTFS. They may be wrong!
*/
if (0 < FileNode->MainFileNode->MainFileDenyDeleteCount)
{
if (!FlagOn(ShareAccess, FILE_SHARE_DELETE) &&
FlagOn(GrantedAccess,
FILE_EXECUTE | FILE_READ_DATA | FILE_WRITE_DATA | FILE_APPEND_DATA | DELETE))
{
OpenedFileNode = FileNode->MainFileNode;
*PSharingViolationReason = FspFileNodeSharingViolationMainFile;
Result = STATUS_SHARING_VIOLATION;
goto exit;
}
}
}
OpenedFileNode = FspFsvolDeviceInsertContextByName(FsvolDeviceObject,
&FileNode->FileName, FileNode, &FileNode->ContextByNameElementStorage, &Inserted);
ASSERT(0 != OpenedFileNode);
if (Inserted)
{
/*
* The new FileNode was inserted into the Context table. Set its share access
* and reference and open it. There should be (at least) two references to this
* FileNode, one from our caller and one from the Context table.
*/
ASSERT(OpenedFileNode == FileNode);
IoSetShareAccess(GrantedAccess, ShareAccess, FileObject,
&OpenedFileNode->ShareAccess);
}
else
{
/*
* The new FileNode was NOT inserted into the Context table. Instead we are
* opening a prior FileNode that we found in the table.
*/
ASSERT(OpenedFileNode != FileNode);
ASSERT(OpenedFileNode->MainFileNode == FileNode->MainFileNode);
DeletePending = 0 != OpenedFileNode->DeletePending;
MemoryBarrier();
if (DeletePending)
{
Result = STATUS_DELETE_PENDING;
goto exit;
}
/*
* Sharing violations between main file and streams were determined
* through experimentation with NTFS. They may be wrong!
*/
if (0 < OpenedFileNode->StreamDenyDeleteCount)
{
/* we must be the main file! */
ASSERT(0 == OpenedFileNode->MainFileNode);
if (FlagOn(GrantedAccess, DELETE))
{
*PSharingViolationReason = FspFileNodeSharingViolationStream;
Result = STATUS_SHARING_VIOLATION;
goto exit;
}
}
/*
* FastFat says to do the following on Vista and above.
*
* Quote:
* Do an extra test for writeable user sections if the user did not allow
* write sharing - this is neccessary since a section may exist with no handles
* open to the file its based against.
*/
if (!FlagOn(ShareAccess, FILE_SHARE_WRITE) &&
FlagOn(GrantedAccess,
FILE_EXECUTE | FILE_READ_DATA | FILE_WRITE_DATA | FILE_APPEND_DATA | DELETE) &&
MmDoesFileHaveUserWritableReferences(&OpenedFileNode->NonPaged->SectionObjectPointers))
{
Result = STATUS_SHARING_VIOLATION;
goto exit;
}
/* share access check */
Result = IoCheckShareAccess(GrantedAccess, ShareAccess, FileObject,
&OpenedFileNode->ShareAccess, TRUE);
if (!NT_SUCCESS(Result))
goto exit;
}
/*
* No more failures allowed at this point!
* This is because we have potentially inserted a new FileNode into the Context table.
* We also updated OpenedFileNode->ShareAccess in IoSetShareAccess/IoCheckShareAccess.
*/
/*
* Sharing violations between main file and streams were determined
* through experimentation with NTFS. They may be wrong!
*/
if (0 == OpenedFileNode->MainFileNode)
{
if (FileObject->DeleteAccess)
OpenedFileNode->MainFileDenyDeleteCount++;
}
else
{
if ((FileObject->ReadAccess || FileObject->WriteAccess || FileObject->DeleteAccess) &&
!FileObject->SharedDelete)
OpenedFileNode->MainFileNode->StreamDenyDeleteCount++;
}
Result = STATUS_SUCCESS;
exit:
if (!NT_SUCCESS(Result) && STATUS_SHARING_VIOLATION != Result)
OpenedFileNode = 0;
if (0 != OpenedFileNode)
{
FspFileNodeReference(OpenedFileNode);
ASSERT(0 <= OpenedFileNode->ActiveCount);
ASSERT(0 <= OpenedFileNode->OpenCount);
ASSERT(0 <= OpenedFileNode->HandleCount);
if (0 == OpenedFileNode->ActiveCount++)
InsertTailList(&FspFsvolDeviceExtension(FsvolDeviceObject)->ContextList,
&FileNode->ActiveEntry);
OpenedFileNode->OpenCount++;
OpenedFileNode->HandleCount++;
}
FspFsvolDeviceUnlockContextTable(FsvolDeviceObject);
*POpenedFileNode = OpenedFileNode;
return Result;
}
VOID FspFileNodeCleanup(FSP_FILE_NODE *FileNode, PFILE_OBJECT FileObject, PULONG PCleanupFlags)
{
/*
* Determine whether a FileNode should be deleted. Note that when FileNode->DeletePending
* is set, the OpenCount/HandleCount cannot be increased because FspFileNodeOpen() will
* return STATUS_DELETE_PENDING.
*
* The FileNode must be acquired exclusive (Main) when calling this function.
*/
PAGED_CODE();
PDEVICE_OBJECT FsvolDeviceObject = FileNode->FsvolDeviceObject;
FSP_FILE_DESC *FileDesc = FileObject->FsContext2;
BOOLEAN DeletePending, SetAllocationSize, SingleHandle;
FspFsvolDeviceLockContextTable(FsvolDeviceObject);
if (FileDesc->DeleteOnClose)
FileNode->DeletePending = TRUE;
DeletePending = 0 != FileNode->DeletePending;
MemoryBarrier();
SetAllocationSize = !DeletePending && FileNode->TruncateOnClose;
SingleHandle = 1 == FileNode->HandleCount;
FspFsvolDeviceUnlockContextTable(FsvolDeviceObject);
*PCleanupFlags = SingleHandle ? DeletePending | (SetAllocationSize << 1) : 0;
}
VOID FspFileNodeCleanupFlush(FSP_FILE_NODE *FileNode, PFILE_OBJECT FileObject)
{
/*
* Optionally flush the FileNode during Cleanup.
*
* The FileNode must be acquired exclusive (Full) when calling this function.
*/
PAGED_CODE();
PDEVICE_OBJECT FsvolDeviceObject = FileNode->FsvolDeviceObject;
FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension = FspFsvolDeviceExtension(FsvolDeviceObject);
if (!FsvolDeviceExtension->VolumeParams.FlushAndPurgeOnCleanup)
return; /* nothing to do! */
BOOLEAN DeletePending, SingleHandle;
LARGE_INTEGER TruncateSize, *PTruncateSize = 0;
FspFsvolDeviceLockContextTable(FsvolDeviceObject);
DeletePending = 0 != FileNode->DeletePending;
MemoryBarrier();
SingleHandle = 1 == FileNode->HandleCount;
if (SingleHandle && FileNode->TruncateOnClose)
{
/*
* Even when the FileInfo is expired, this is the best guess for a file size
* without asking the user-mode file system.
*/
TruncateSize = FileNode->Header.FileSize;
PTruncateSize = &TruncateSize;
}
FspFsvolDeviceUnlockContextTable(FsvolDeviceObject);
/* Flush and purge on last Cleanup. Keeps files off the "standby" list. (GitHub issue #104) */
if (SingleHandle && !DeletePending)
{
IO_STATUS_BLOCK IoStatus;
LARGE_INTEGER ZeroOffset = { 0 };
if (0 != PTruncateSize && 0 == PTruncateSize->HighPart)
FspCcFlushCache(FileObject->SectionObjectPointer, &ZeroOffset, PTruncateSize->LowPart,
&IoStatus);
else
FspCcFlushCache(FileObject->SectionObjectPointer, 0, 0,
&IoStatus);
}
}
VOID FspFileNodeCleanupComplete(FSP_FILE_NODE *FileNode, PFILE_OBJECT FileObject)
{
/*
* Complete the cleanup of a FileNode. Remove its share access and
* finalize its cache.
*
* NOTE: If the FileNode is not being deleted (!FileNode->DeletePending)
* the FileNode REMAINS in the Context table until Close time!
* This is so that if there are mapped views or write behind's pending
* when a file gets reopened the FileNode will be correctly reused.
*
* The FileNode must be acquired exclusive (Main) when calling this function.
*/
PAGED_CODE();
PDEVICE_OBJECT FsvolDeviceObject = FileNode->FsvolDeviceObject;
FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension = FspFsvolDeviceExtension(FsvolDeviceObject);
LARGE_INTEGER TruncateSize, *PTruncateSize = 0;
BOOLEAN DeletePending, DeletedFromContextTable = FALSE, SingleHandle = FALSE;
FspFsvolDeviceLockContextTable(FsvolDeviceObject);
/*
* Sharing violations between main file and streams were determined
* through experimentation with NTFS. They may be wrong!
*/
if (0 == FileNode->MainFileNode)
{
if (FileObject->DeleteAccess)
FileNode->MainFileDenyDeleteCount--;
}
else
{
if ((FileObject->ReadAccess || FileObject->WriteAccess || FileObject->DeleteAccess) &&
!FileObject->SharedDelete)
FileNode->MainFileNode->StreamDenyDeleteCount--;
}
IoRemoveShareAccess(FileObject, &FileNode->ShareAccess);
ASSERT(0 < FileNode->HandleCount);
if (0 == --FileNode->HandleCount)
{
SingleHandle = TRUE;
DeletePending = 0 != FileNode->DeletePending;
MemoryBarrier();
if (DeletePending)
{
FspFsvolDeviceDeleteContextByName(FsvolDeviceObject, &FileNode->FileName,
&DeletedFromContextTable);
ASSERT(DeletedFromContextTable);
FileNode->OpenCount = 0;
FileNode->Header.FileSize.QuadPart = 0;
/*
* We now have to deal with the scenario where there are cleaned up,
* but unclosed streams for this file still in the context table.
*/
if (FsvolDeviceExtension->VolumeParams.NamedStreams &&
0 == FileNode->MainFileNode)
{
BOOLEAN StreamDeletedFromContextTable;
USHORT FileNameLength = FileNode->FileName.Length;
GATHER_DESCENDANTS(&FileNode->FileName, FALSE,
if (DescendantFileNode->FileName.Length > FileNameLength &&
L'\\' == DescendantFileNode->FileName.Buffer[FileNameLength / sizeof(WCHAR)])
break;
ASSERT(FileNode != DescendantFileNode);
ASSERT(0 != DescendantFileNode->OpenCount);
ASSERT(0 == DescendantFileNode->HandleCount);
);
for (
DescendantFileNodeIndex = 0;
DescendantFileNodeCount > DescendantFileNodeIndex;
DescendantFileNodeIndex++)
{
DescendantFileNode = DescendantFileNodes[DescendantFileNodeIndex];
FspFsvolDeviceDeleteContextByName(FsvolDeviceObject, &DescendantFileNode->FileName,
&StreamDeletedFromContextTable);
if (StreamDeletedFromContextTable)
{
DescendantFileNode->OpenCount = 0;
FspFileNodeDereference(DescendantFileNode);
}
}
SCATTER_DESCENDANTS(FALSE);
}
}
if (DeletePending || FileNode->TruncateOnClose)
{
UINT64 AllocationUnit =
FsvolDeviceExtension->VolumeParams.SectorSize *
FsvolDeviceExtension->VolumeParams.SectorsPerAllocationUnit;
/*
* Even when the FileInfo is expired, this is the best guess for a file size
* without asking the user-mode file system.
*/
TruncateSize = FileNode->Header.FileSize;
PTruncateSize = &TruncateSize;
FileNode->Header.AllocationSize.QuadPart = (TruncateSize.QuadPart + AllocationUnit - 1)
/ AllocationUnit * AllocationUnit;
}
FileNode->TruncateOnClose = FALSE;
}
FspFsvolDeviceUnlockContextTable(FsvolDeviceObject);
/* Flush and purge on last Cleanup. Keeps files off the "standby" list. (GitHub issue #104) */
if (SingleHandle && FsvolDeviceExtension->VolumeParams.FlushAndPurgeOnCleanup)
{
/*
* There is an important difference in behavior with respect to DeletePending when
* FlushAndPurgeOnCleanup is FALSE vs when it is TRUE.
*
* With FlushAndPurgeOnCleanup==FALSE (the default), the WinFsp FSD preserves data
* and allows a deleted file to have memory-mapped I/O done on it after the CLEANUP
* completes. It is up to the user mode file system to decide whether to handle
* this scenario or not. The MEMFS reference file system does.
*
* With FlushAndPurgeOnCleanup==TRUE, the FSD simply purges the cache section (if any),
* which means that CACHED DATA WILL BE LOST. This is desirable, because we do not want
* to unnecessarily flush data that are soon going to be deleted.
*
* This could affect a program that does memory-mapped I/O on a deleted file that has
* been CloseHandle'd. Tests have shown that even NTFS cannot properly handle this
* scenario in all cases (for example, when the file is not cached), so it is unlikely
* that there are any useful programs out there that do this.
*
* So we deem this difference in behavior ok and desirable.
*/
TruncateSize.QuadPart = 0;
PTruncateSize = &TruncateSize;
}