__drv_mustHoldCriticalRegion
NTSTATUS
CdQueryDirectory (
__inout PIRP_CONTEXT IrpContext,
__inout PIRP Irp,
__in PIO_STACK_LOCATION IrpSp,
__in PFCB Fcb,
__in PCCB Ccb
)
/*++
Routine Description:
This routine performs the query directory operation. It is responsible
for either completing of enqueuing the input Irp. We store the state of the
search in the Ccb.
Arguments:
Irp - Supplies the Irp to process
IrpSp - Stack location for this Irp.
Fcb - Fcb for this directory.
Ccb - Ccb for this directory open.
Return Value:
NTSTATUS - The return status for the operation
--*/
{
NTSTATUS Status = STATUS_SUCCESS;
ULONG Information = 0;
ULONG LastEntry = 0;
ULONG NextEntry = 0;
ULONG FileNameBytes;
ULONG SeparatorBytes;
ULONG VersionStringBytes;
FILE_ENUM_CONTEXT FileContext;
PDIRENT ThisDirent = NULL;
BOOLEAN InitialQuery;
BOOLEAN ReturnNextEntry = FALSE;
BOOLEAN ReturnSingleEntry;
BOOLEAN Found;
BOOLEAN DoCcbUpdate = FALSE;
PCHAR UserBuffer;
ULONG BytesRemainingInBuffer;
ULONG BaseLength;
PFILE_BOTH_DIR_INFORMATION DirInfo = NULL;
PFILE_NAMES_INFORMATION NamesInfo;
PFILE_ID_FULL_DIR_INFORMATION IdFullDirInfo;
PFILE_ID_BOTH_DIR_INFORMATION IdBothDirInfo;
PAGED_CODE();
//
// Check if we support this search mode. Also remember the size of the base part of
// each of these structures.
//
switch (IrpSp->Parameters.QueryDirectory.FileInformationClass) {
case FileDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_DIRECTORY_INFORMATION,
FileName[0] );
break;
case FileFullDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_FULL_DIR_INFORMATION,
FileName[0] );
break;
case FileIdFullDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_ID_FULL_DIR_INFORMATION,
FileName[0] );
break;
case FileNamesInformation:
BaseLength = FIELD_OFFSET( FILE_NAMES_INFORMATION,
FileName[0] );
break;
case FileBothDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_BOTH_DIR_INFORMATION,
FileName[0] );
break;
case FileIdBothDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_ID_BOTH_DIR_INFORMATION,
FileName[0] );
break;
default:
CdCompleteRequest( IrpContext, Irp, STATUS_INVALID_INFO_CLASS );
return STATUS_INVALID_INFO_CLASS;
}
//
// Get the user buffer.
//
CdMapUserBuffer( IrpContext, &UserBuffer);
//
// Initialize our search context.
//
CdInitializeFileContext( IrpContext, &FileContext );
//
// Acquire the directory.
//
CdAcquireFileShared( IrpContext, Fcb );
//
// Use a try-finally to facilitate cleanup.
//
try {
//
// Verify the Fcb is still good.
//
CdVerifyFcbOperation( IrpContext, Fcb );
//
// Start by getting the initial state for the enumeration. This will set up the Ccb with
// the initial search parameters and let us know the starting offset in the directory
// to search.
//
CdInitializeEnumeration( IrpContext,
IrpSp,
Fcb,
Ccb,
&FileContext,
&ReturnNextEntry,
&ReturnSingleEntry,
&InitialQuery );
//
// The current dirent is stored in the InitialDirent field. We capture
// this here so that we have a valid restart point even if we don't
// find a single entry.
//
ThisDirent = &FileContext.InitialDirent->Dirent;
//
// At this point we are about to enter our query loop. We have
// determined the index into the directory file to begin the
// search. LastEntry and NextEntry are used to index into the user
// buffer. LastEntry is the last entry we've added, NextEntry is
// current one we're working on. If NextEntry is non-zero, then
// at least one entry was added.
//
while (TRUE) {
//
// If the user had requested only a single match and we have
// returned that, then we stop at this point. We update the Ccb with
// the status based on the last entry returned.
//
if ((NextEntry != 0) && ReturnSingleEntry) {
DoCcbUpdate = TRUE;
try_leave( Status );
}
//
// We try to locate the next matching dirent. Our search if based on a starting
// dirent offset, whether we should return the current or next entry, whether
// we should be doing a short name search and finally whether we should be
// checking for a version match.
//
Found = CdEnumerateIndex( IrpContext, Ccb, &FileContext, ReturnNextEntry );
//
// Initialize the value for the next search.
//
ReturnNextEntry = TRUE;
//
// If we didn't receive a dirent, then we are at the end of the
// directory. If we have returned any files, we exit with
// success, otherwise we return STATUS_NO_MORE_FILES.
//
if (!Found) {
if (NextEntry == 0) {
Status = STATUS_NO_MORE_FILES;
if (InitialQuery) {
Status = STATUS_NO_SUCH_FILE;
}
}
DoCcbUpdate = TRUE;
try_leave( Status );
}
//
// Remember the dirent for the file we just found.
//
ThisDirent = &FileContext.InitialDirent->Dirent;
//
// Here are the rules concerning filling up the buffer:
//
// 1. The Io system garentees that there will always be
// enough room for at least one base record.
//
// 2. If the full first record (including file name) cannot
// fit, as much of the name as possible is copied and
// STATUS_BUFFER_OVERFLOW is returned.
//
// 3. If a subsequent record cannot completely fit into the
// buffer, none of it (as in 0 bytes) is copied, and
// STATUS_SUCCESS is returned. A subsequent query will
// pick up with this record.
//
//
// Let's compute the number of bytes we need to transfer the current entry.
//
SeparatorBytes =
VersionStringBytes = 0;
//
// We can look directly at the dirent that we found.
//
FileNameBytes = ThisDirent->CdFileName.FileName.Length;
//
// Compute the number of bytes for the version string if
// we will return this. Allow directories with illegal ";".
//
if (((Ccb->SearchExpression.VersionString.Length != 0) ||
(FlagOn(ThisDirent->DirentFlags, CD_ATTRIBUTE_DIRECTORY))) &&
(ThisDirent->CdFileName.VersionString.Length != 0)) {
SeparatorBytes = 2;
VersionStringBytes = ThisDirent->CdFileName.VersionString.Length;
}
//
// If the slot for the next entry would be beyond the length of the
// user's buffer just exit (we know we've returned at least one entry
// already). This will happen when we align the pointer past the end.
//
if (NextEntry > IrpSp->Parameters.QueryDirectory.Length) {
ReturnNextEntry = FALSE;
DoCcbUpdate = TRUE;
try_leave( Status = STATUS_SUCCESS );
}
//
// Compute the number of bytes remaining in the buffer. Round this
// down to a WCHAR boundary so we can copy full characters.
//
BytesRemainingInBuffer = IrpSp->Parameters.QueryDirectory.Length - NextEntry;
ClearFlag( BytesRemainingInBuffer, 1 );
//
// If this won't fit and we have returned a previous entry then just
// return STATUS_SUCCESS.
//
if ((BaseLength + FileNameBytes + SeparatorBytes + VersionStringBytes) > BytesRemainingInBuffer) {
//
// If we already found an entry then just exit.
//
if (NextEntry != 0) {
ReturnNextEntry = FALSE;
DoCcbUpdate = TRUE;
try_leave( Status = STATUS_SUCCESS );
}
//
// Don't even try to return the version string if it doesn't all fit.
// Reduce the FileNameBytes to just fit in the buffer.
//
if ((BaseLength + FileNameBytes) > BytesRemainingInBuffer) {
FileNameBytes = BytesRemainingInBuffer - BaseLength;
}
//
// Don't return any version string bytes.
//
VersionStringBytes =
SeparatorBytes = 0;
//
// Use a status code of STATUS_BUFFER_OVERFLOW. Also set
// ReturnSingleEntry so that we will exit the loop at the top.
//
Status = STATUS_BUFFER_OVERFLOW;
ReturnSingleEntry = TRUE;
}
//
// Protect access to the user buffer with an exception handler.
// Since (at our request) IO doesn't buffer these requests, we have
// to guard against a user messing with the page protection and other
// such trickery.
//
try {
//
// Zero and initialize the base part of the current entry.
//
RtlZeroMemory( Add2Ptr( UserBuffer, NextEntry, PVOID ),
BaseLength );
//
// Now we have an entry to return to our caller.
// We'll case on the type of information requested and fill up
// the user buffer if everything fits.
//
switch (IrpSp->Parameters.QueryDirectory.FileInformationClass) {
case FileBothDirectoryInformation:
case FileFullDirectoryInformation:
case FileIdBothDirectoryInformation:
case FileIdFullDirectoryInformation:
case FileDirectoryInformation:
DirInfo = Add2Ptr( UserBuffer, NextEntry, PFILE_BOTH_DIR_INFORMATION );
//
// Use the create time for all the time stamps.
//
CdConvertCdTimeToNtTime( IrpContext,
FileContext.InitialDirent->Dirent.CdTime,
&DirInfo->CreationTime );
DirInfo->LastWriteTime = DirInfo->ChangeTime = DirInfo->CreationTime;
//
// Set the attributes and sizes separately for directories and
// files.
//
if (FlagOn( ThisDirent->DirentFlags, CD_ATTRIBUTE_DIRECTORY )) {
DirInfo->EndOfFile.QuadPart = DirInfo->AllocationSize.QuadPart = 0;
SetFlag( DirInfo->FileAttributes, FILE_ATTRIBUTE_DIRECTORY);
} else {
DirInfo->EndOfFile.QuadPart = FileContext.FileSize;
DirInfo->AllocationSize.QuadPart = LlSectorAlign( FileContext.FileSize );
SetFlag( DirInfo->FileAttributes, FILE_ATTRIBUTE_READONLY);
}
if (FlagOn( ThisDirent->DirentFlags,
CD_ATTRIBUTE_HIDDEN )) {
SetFlag( DirInfo->FileAttributes, FILE_ATTRIBUTE_HIDDEN );
}
DirInfo->FileIndex = ThisDirent->DirentOffset;
DirInfo->FileNameLength = FileNameBytes + SeparatorBytes + VersionStringBytes;
break;
case FileNamesInformation:
NamesInfo = Add2Ptr( UserBuffer, NextEntry, PFILE_NAMES_INFORMATION );
NamesInfo->FileIndex = ThisDirent->DirentOffset;
NamesInfo->FileNameLength = FileNameBytes + SeparatorBytes + VersionStringBytes;
break;
}
//
// Fill in the FileId
//
switch (IrpSp->Parameters.QueryDirectory.FileInformationClass) {
case FileIdBothDirectoryInformation:
IdBothDirInfo = Add2Ptr( UserBuffer, NextEntry, PFILE_ID_BOTH_DIR_INFORMATION );
CdSetFidFromParentAndDirent( IdBothDirInfo->FileId, Fcb, ThisDirent );
break;
case FileIdFullDirectoryInformation:
IdFullDirInfo = Add2Ptr( UserBuffer, NextEntry, PFILE_ID_FULL_DIR_INFORMATION );
CdSetFidFromParentAndDirent( IdFullDirInfo->FileId, Fcb, ThisDirent );
break;
default:
break;
}
//
// Now copy as much of the name as possible. We also may have a version
// string to copy.
//
if (FileNameBytes != 0) {
//
// This is a Unicode name, we can copy the bytes directly.
//
RtlCopyMemory( Add2Ptr( UserBuffer, NextEntry + BaseLength, PVOID ),
ThisDirent->CdFileName.FileName.Buffer,
FileNameBytes );
if (SeparatorBytes != 0) {
*(Add2Ptr( UserBuffer,
NextEntry + BaseLength + FileNameBytes,
PWCHAR )) = L';';
if (VersionStringBytes != 0) {
RtlCopyMemory( Add2Ptr( UserBuffer,
NextEntry + BaseLength + FileNameBytes + sizeof( WCHAR ),
PVOID ),
ThisDirent->CdFileName.VersionString.Buffer,
VersionStringBytes );
}
}
}
//
// Fill in the short name if we got STATUS_SUCCESS. The short name
// may already be in the file context. Otherwise we will check
// whether the long name is 8.3. Special case the self and parent
// directory names.
//
if ((Status == STATUS_SUCCESS) &&
(IrpSp->Parameters.QueryDirectory.FileInformationClass == FileBothDirectoryInformation ||
IrpSp->Parameters.QueryDirectory.FileInformationClass == FileIdBothDirectoryInformation) &&
(Ccb->SearchExpression.VersionString.Length == 0) &&
!FlagOn( ThisDirent->Flags, DIRENT_FLAG_CONSTANT_ENTRY )) {
//
// If we already have the short name then copy into the user's buffer.
//
if (FileContext.ShortName.FileName.Length != 0) {
RtlCopyMemory( DirInfo->ShortName,
FileContext.ShortName.FileName.Buffer,
FileContext.ShortName.FileName.Length );
DirInfo->ShortNameLength = (CCHAR) FileContext.ShortName.FileName.Length;
//
// If the short name length is currently zero then check if
// the long name is not 8.3. We can copy the short name in
// unicode form directly into the caller's buffer.
//
} else {
if (!CdIs8dot3Name( IrpContext,
ThisDirent->CdFileName.FileName )) {
CdGenerate8dot3Name( IrpContext,
&ThisDirent->CdCaseFileName.FileName,
ThisDirent->DirentOffset,
DirInfo->ShortName,
&FileContext.ShortName.FileName.Length );
DirInfo->ShortNameLength = (CCHAR) FileContext.ShortName.FileName.Length;
}
}
}
//
// Sum the total number of bytes for the information field.
//
FileNameBytes += SeparatorBytes + VersionStringBytes;
//
// Update the information with the number of bytes stored in the
// buffer. We quad-align the existing buffer to add any necessary
// pad bytes.
//
Information = NextEntry + BaseLength + FileNameBytes;
//
// Go back to the previous entry and fill in the update to this entry.
//
*(Add2Ptr( UserBuffer, LastEntry, PULONG )) = NextEntry - LastEntry;
//
// Set up our variables for the next dirent.
//
InitialQuery = FALSE;
LastEntry = NextEntry;
NextEntry = QuadAlign( Information );
} except (EXCEPTION_EXECUTE_HANDLER) {
//
// We had a problem filling in the user's buffer, so stop and
// fail this request. This is the only reason any exception
// would have occured at this level.
//
Information = 0;
try_leave( Status = GetExceptionCode());
}
}
DoCcbUpdate = TRUE;
} finally {
//
// Cleanup our search context - *before* aquiring the FCB mutex exclusive,
// else can block on threads in cdcreateinternalstream/purge which
// hold the FCB but are waiting for all maps in this stream to be released.
//
CdCleanupFileContext( IrpContext, &FileContext );
//
// Now we can safely aqure the FCB mutex if we need to.
//
if (DoCcbUpdate && !NT_ERROR( Status )) {
//
// Update the Ccb to show the current state of the enumeration.
//
CdLockFcb( IrpContext, Fcb );
Ccb->CurrentDirentOffset = ThisDirent->DirentOffset;
ClearFlag( Ccb->Flags, CCB_FLAG_ENUM_RETURN_NEXT );
if (ReturnNextEntry) {
SetFlag( Ccb->Flags, CCB_FLAG_ENUM_RETURN_NEXT );
}
CdUnlockFcb( IrpContext, Fcb );
}
//
// Release the Fcb.
//
CdReleaseFile( IrpContext, Fcb );
}
//
// Complete the request here.
//
Irp->IoStatus.Information = Information;
CdCompleteRequest( IrpContext, Irp, Status );
return Status;
}
NTSTATUS
CdCommonWrite (
_Inout_ PIRP_CONTEXT IrpContext,
_Inout_ PIRP Irp
)
/*++
Routine Description:
This is the common entry point for NtWriteFile calls. For synchronous requests,
CommonWrite will complete the request in the current thread. If not
synchronous the request will be passed to the Fsp if there is a need to
block.
Arguments:
Irp - Supplies the Irp to process
Return Value:
NTSTATUS - The result of this operation.
--*/
{
NTSTATUS Status = STATUS_SUCCESS;
PIO_STACK_LOCATION IrpSp = IoGetCurrentIrpStackLocation( Irp );
TYPE_OF_OPEN TypeOfOpen;
PFCB Fcb;
PCCB Ccb;
BOOLEAN Wait;
ULONG SynchronousIo;
PVOID UserBuffer;
LONGLONG StartingOffset;
LONGLONG ByteRange;
ULONG ByteCount;
ULONG WriteByteCount;
ULONG OriginalByteCount;
BOOLEAN ReleaseFile = TRUE;
CD_IO_CONTEXT LocalIoContext;
PAGED_CODE();
//
// If this is a zero length write then return SUCCESS immediately.
//
if (IrpSp->Parameters.Write.Length == 0) {
CdCompleteRequest( IrpContext, Irp, STATUS_SUCCESS );
return STATUS_SUCCESS;
}
//
// Decode the file object and verify we support write on this. It
// must be a volume file.
//
TypeOfOpen = CdDecodeFileObject( IrpContext, IrpSp->FileObject, &Fcb, &Ccb );
// Internal lock object is acquired if return status is STATUS_PENDING
_Analysis_suppress_lock_checking_(Fcb->Resource);
if (TypeOfOpen != UserVolumeOpen) {
CdCompleteRequest( IrpContext, Irp, STATUS_INVALID_DEVICE_REQUEST );
return STATUS_INVALID_DEVICE_REQUEST;
}
//
// Examine our input parameters to determine if this is noncached and/or
// a paging io operation.
//
Wait = BooleanFlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT );
SynchronousIo = FlagOn( IrpSp->FileObject->Flags, FO_SYNCHRONOUS_IO );
//
// Extract the range of the Io.
//
StartingOffset = IrpSp->Parameters.Write.ByteOffset.QuadPart;
OriginalByteCount = ByteCount = IrpSp->Parameters.Write.Length;
ByteRange = StartingOffset + ByteCount;
//
// Acquire the file shared to perform the write.
//
CdAcquireFileShared( IrpContext, Fcb );
//
// Use a try-finally to facilitate cleanup.
//
try {
//
// Verify the Fcb. Allow writes if this is a DASD handle that is
// dismounting the volume.
//
if (!FlagOn( Ccb->Flags, CCB_FLAG_DISMOUNT_ON_CLOSE )) {
CdVerifyFcbOperation( IrpContext, Fcb );
}
if (!FlagOn( Ccb->Flags, CCB_FLAG_ALLOW_EXTENDED_DASD_IO )) {
//
// Complete the request if it begins beyond the end of file.
//
if (StartingOffset >= Fcb->FileSize.QuadPart) {
try_return( Status = STATUS_END_OF_FILE );
}
//
// Truncate the write if it extends beyond the end of the file.
//
if (ByteRange > Fcb->FileSize.QuadPart) {
ByteCount = (ULONG) (Fcb->FileSize.QuadPart - StartingOffset);
ByteRange = Fcb->FileSize.QuadPart;
}
}
//
// If we have an unaligned transfer then post this request if
// we can't wait. Unaligned means that the starting offset
// is not on a sector boundary or the write is not integral
// sectors.
//
WriteByteCount = BlockAlign( Fcb->Vcb, ByteCount );
if (SectorOffset( StartingOffset ) ||
SectorOffset( WriteByteCount ) ||
(WriteByteCount > OriginalByteCount)) {
if (!Wait) {
CdRaiseStatus( IrpContext, STATUS_CANT_WAIT );
}
//
// Make sure we don't overwrite the buffer.
//
WriteByteCount = ByteCount;
}
//
// Initialize the IoContext for the write.
// If there is a context pointer, we need to make sure it was
// allocated and not a stale stack pointer.
//
if (IrpContext->IoContext == NULL ||
!FlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_ALLOC_IO )) {
//
// If we can wait, use the context on the stack. Otherwise
// we need to allocate one.
//
if (Wait) {
IrpContext->IoContext = &LocalIoContext;
ClearFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_ALLOC_IO );
} else {
IrpContext->IoContext = CdAllocateIoContext();
SetFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_ALLOC_IO );
}
}
RtlZeroMemory( IrpContext->IoContext, sizeof( CD_IO_CONTEXT ) );
//
// Store whether we allocated this context structure in the structure
// itself.
//
IrpContext->IoContext->AllocatedContext =
BooleanFlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_ALLOC_IO );
if (Wait) {
KeInitializeEvent( &IrpContext->IoContext->SyncEvent,
NotificationEvent,
FALSE );
} else {
IrpContext->IoContext->ResourceThreadId = ExGetCurrentResourceThread();
IrpContext->IoContext->Resource = Fcb->Resource;
IrpContext->IoContext->RequestedByteCount = ByteCount;
}
Irp->IoStatus.Information = WriteByteCount;
//
// Set the FO_MODIFIED flag here to trigger a verify when this
// handle is closed. Note that we can err on the conservative
// side with no problem, i.e. if we accidently do an extra
// verify there is no problem.
//
SetFlag( IrpSp->FileObject->Flags, FO_FILE_MODIFIED );
//
// Dasd access is always non-cached. Call the Dasd write routine to
// perform the actual write.
//
Status = CdVolumeDasdWrite( IrpContext, Fcb, StartingOffset, WriteByteCount );
//
// Don't complete this request now if STATUS_PENDING was returned.
//
if (Status == STATUS_PENDING) {
Irp = NULL;
ReleaseFile = FALSE;
//
// Test is we should zero part of the buffer or update the
// synchronous file position.
//
} else {
//
// Convert any unknown error code to IO_ERROR.
//
if (!NT_SUCCESS( Status )) {
//
// Set the information field to zero.
//
Irp->IoStatus.Information = 0;
//
// Raise if this is a user induced error.
//
if (IoIsErrorUserInduced( Status )) {
CdRaiseStatus( IrpContext, Status );
}
Status = FsRtlNormalizeNtstatus( Status, STATUS_UNEXPECTED_IO_ERROR );
//
// Check if there is any portion of the user's buffer to zero.
//
} else if (WriteByteCount != ByteCount) {
CdMapUserBuffer( IrpContext, &UserBuffer );
SafeZeroMemory( IrpContext,
Add2Ptr( UserBuffer,
ByteCount,
PVOID ),
WriteByteCount - ByteCount );
Irp->IoStatus.Information = ByteCount;
}
//
// Update the file position if this is a synchronous request.
//
if (SynchronousIo && NT_SUCCESS( Status )) {
IrpSp->FileObject->CurrentByteOffset.QuadPart = ByteRange;
}
}
try_exit: NOTHING;
} finally {
//
// Release the Fcb.
//
if (ReleaseFile) {
CdReleaseFile( IrpContext, Fcb );
}
}
//
// Post the request if we got CANT_WAIT.
//
if (Status == STATUS_CANT_WAIT) {
Status = CdFsdPostRequest( IrpContext, Irp );
//
// Otherwise complete the request.
//
} else {
CdCompleteRequest( IrpContext, Irp, Status );
}
return Status;
}
__drv_mustHoldCriticalRegion
NTSTATUS
CdCommonSetInfo (
__inout PIRP_CONTEXT IrpContext,
__inout PIRP Irp
)
/*++
Routine Description:
This is the common routine for set file information called by both the
fsd and fsp threads. We only support operations which set the file position.
Arguments:
Irp - Supplies the Irp to process.
Return Value:
NTSTATUS - The return status for this operation.
--*/
{
NTSTATUS Status = STATUS_INVALID_PARAMETER;
TYPE_OF_OPEN TypeOfOpen;
PFCB Fcb;
PCCB Ccb;
PIO_STACK_LOCATION IrpSp = IoGetCurrentIrpStackLocation( Irp );
PFILE_POSITION_INFORMATION Buffer;
PAGED_CODE();
//
// Decode the file object
//
TypeOfOpen = CdDecodeFileObject( IrpContext, IrpSp->FileObject, &Fcb, &Ccb );
//
// We only support a SetPositionInformation on a user file.
//
if ((TypeOfOpen != UserFileOpen) ||
(IrpSp->Parameters.QueryFile.FileInformationClass != FilePositionInformation)) {
CdCompleteRequest( IrpContext, Irp, Status );
return Status;
}
//
// Acquire shared access to this file.
//
CdAcquireFileShared( IrpContext, Fcb );
try {
//
// Make sure the Fcb is in a usable condition. This
// will raise an error condition if the fcb is unusable
//
CdVerifyFcbOperation( IrpContext, Fcb );
Buffer = Irp->AssociatedIrp.SystemBuffer;
//
// Check if the file does not use intermediate buffering. If it
// does not use intermediate buffering then the new position we're
// supplied must be aligned properly for the device
//
if (FlagOn( IrpSp->FileObject->Flags, FO_NO_INTERMEDIATE_BUFFERING ) &&
((Buffer->CurrentByteOffset.LowPart & Fcb->Vcb->BlockMask) != 0)) {
try_return( NOTHING );
}
//
// The input parameter is fine so set the current byte offset and
// complete the request
//
//
// Lock the Fcb to provide synchronization.
//
CdLockFcb( IrpContext, Fcb );
IrpSp->FileObject->CurrentByteOffset = Buffer->CurrentByteOffset;
CdUnlockFcb( IrpContext, Fcb );
Status = STATUS_SUCCESS;
try_exit: NOTHING;
} finally {
#pragma prefast( suppress: 28107, "prefast cannot work out that the FCB is already acquired")
CdReleaseFile( IrpContext, Fcb );
}
//
// Complete the request if there was no raise.
//
CdCompleteRequest( IrpContext, Irp, Status );
return Status;
}
__drv_mustHoldCriticalRegion
NTSTATUS
CdQueryAlternateNameInfo (
__in PIRP_CONTEXT IrpContext,
__in PFCB Fcb,
__in PCCB Ccb,
__out PFILE_NAME_INFORMATION Buffer,
__inout PULONG Length
)
/*++
Routine Description:
This routine performs the query alternate name information function.
We lookup the dirent for this file and then check if there is a
short name.
Arguments:
Fcb - Supplies the Fcb being queried, it has been verified.
Ccb - Ccb for this open handle.
Buffer - Supplies a pointer to the buffer where the information is to
be returned.
Length - Supplies the length of the buffer in bytes, and receives the
remaining bytes free in the buffer upon return.
Return Value:
NTSTATUS - STATUS_SUCCESS if the whole name would fit into the user buffer,
STATUS_OBJECT_NAME_NOT_FOUND if we can't return the name,
STATUS_BUFFER_OVERFLOW otherwise.
--*/
{
NTSTATUS Status = STATUS_SUCCESS;
DIRENT_ENUM_CONTEXT DirContext = {0};
DIRENT Dirent = {0};
PUNICODE_STRING NameToUse;
ULONG DirentOffset;
COMPOUND_PATH_ENTRY CompoundPathEntry = {0};
FILE_ENUM_CONTEXT FileContext;
PFCB ParentFcb = NULL;
BOOLEAN ReleaseParentFcb = FALSE;
BOOLEAN CleanupFileLookup = FALSE;
BOOLEAN CleanupDirectoryLookup = FALSE;
WCHAR ShortNameBuffer[ BYTE_COUNT_8_DOT_3 / 2 ];
USHORT ShortNameLength;
PAGED_CODE();
//
// Initialize the buffer length to zero.
//
Buffer->FileNameLength = 0;
//
// If this is the root or this file was opened using a version number then
// there is no short name.
//
if ((Fcb == Fcb->Vcb->RootIndexFcb) ||
FlagOn( Ccb->Flags, CCB_FLAG_OPEN_WITH_VERSION)) {
return STATUS_OBJECT_NAME_NOT_FOUND;
}
//
// Use a try-finally to cleanup the structures.
//
try {
ParentFcb = Fcb->ParentFcb;
CdAcquireFileShared( IrpContext, ParentFcb );
ReleaseParentFcb = TRUE;
CdVerifyOrCreateDirStreamFile( IrpContext, ParentFcb);
if (CdFidIsDirectory( Fcb->FileId)) {
//
// Fcb is for a directory, so we need to dig the dirent from the parent. In
// order to do this we need to get the name of the directory from its pathtable
// entry and then search in the parent for a matching dirent.
//
// This could be optimized somewhat.
//
CdInitializeCompoundPathEntry( IrpContext, &CompoundPathEntry );
CdInitializeFileContext( IrpContext, &FileContext );
CleanupDirectoryLookup = TRUE;
CdLookupPathEntry( IrpContext,
CdQueryFidPathTableOffset( Fcb->FileId ),
Fcb->Ordinal,
FALSE,
&CompoundPathEntry );
CdUpdatePathEntryName( IrpContext, &CompoundPathEntry.PathEntry, TRUE );
if (!CdFindDirectory( IrpContext,
ParentFcb,
&CompoundPathEntry.PathEntry.CdCaseDirName,
TRUE,
&FileContext )) {
//
// If we failed to find the child directory by name in the parent
// something is quite wrong with this disc.
//
CdRaiseStatus( IrpContext, STATUS_DISK_CORRUPT_ERROR );
}
NameToUse = &FileContext.InitialDirent->Dirent.CdCaseFileName.FileName;
DirentOffset = FileContext.InitialDirent->Dirent.DirentOffset;
} else {
//
// Initialize the search dirent structures.
//
CdInitializeDirContext( IrpContext, &DirContext );
CdInitializeDirent( IrpContext, &Dirent );
CleanupFileLookup = TRUE;
CdLookupDirent( IrpContext,
ParentFcb,
CdQueryFidDirentOffset( Fcb->FileId ),
&DirContext );
CdUpdateDirentFromRawDirent( IrpContext,
ParentFcb,
&DirContext,
&Dirent );
//
// Now update the dirent name.
//
CdUpdateDirentName( IrpContext, &Dirent, TRUE );
NameToUse = &Dirent.CdCaseFileName.FileName;
DirentOffset = Dirent.DirentOffset;
}
//
// If the name is 8.3 then fail this request.
//
if (CdIs8dot3Name( IrpContext,
*NameToUse )) {
try_return( Status = STATUS_OBJECT_NAME_NOT_FOUND );
}
CdGenerate8dot3Name( IrpContext,
NameToUse,
DirentOffset,
ShortNameBuffer,
&ShortNameLength );
//
// We now have the short name. We have left it in Unicode form so copy it directly.
//
Buffer->FileNameLength = ShortNameLength;
if (Buffer->FileNameLength + sizeof( ULONG ) > *Length) {
Buffer->FileNameLength = *Length - sizeof( ULONG );
Status = STATUS_BUFFER_OVERFLOW;
}
RtlCopyMemory( Buffer->FileName, ShortNameBuffer, Buffer->FileNameLength );
try_exit: NOTHING;
} finally {
if (CleanupFileLookup) {
CdCleanupDirContext( IrpContext, &DirContext );
CdCleanupDirent( IrpContext, &Dirent );
} else if (CleanupDirectoryLookup) {
CdCleanupCompoundPathEntry( IrpContext, &CompoundPathEntry );
CdCleanupFileContext( IrpContext, &FileContext );
}
if (ReleaseParentFcb) {
CdReleaseFile( IrpContext, ParentFcb );
}
}
//
// Reduce the available bytes by the amount stored into this buffer.
//
if (Status != STATUS_OBJECT_NAME_NOT_FOUND) {
*Length -= sizeof( ULONG ) + Buffer->FileNameLength;
}
return Status;
}
__drv_mustHoldCriticalRegion
NTSTATUS
CdCommonQueryInfo (
__inout PIRP_CONTEXT IrpContext,
__inout PIRP Irp
)
/*++
Routine Description:
This is the common routine for query file information called by both the
fsd and fsp threads.
Arguments:
Irp - Supplies the Irp to process.
Return Value:
NTSTATUS - The return status for this operation.
--*/
{
NTSTATUS Status = STATUS_SUCCESS;
PIO_STACK_LOCATION IrpSp = IoGetCurrentIrpStackLocation( Irp );
ULONG Length;
FILE_INFORMATION_CLASS FileInformationClass;
PFILE_ALL_INFORMATION Buffer;
TYPE_OF_OPEN TypeOfOpen;
PFCB Fcb;
PCCB Ccb;
BOOLEAN ReleaseFcb = FALSE;
PAGED_CODE();
//
// Reference our input parameters to make things easier
//
Length = IrpSp->Parameters.QueryFile.Length;
FileInformationClass = IrpSp->Parameters.QueryFile.FileInformationClass;
Buffer = Irp->AssociatedIrp.SystemBuffer;
//
// Decode the file object
//
TypeOfOpen = CdDecodeFileObject( IrpContext, IrpSp->FileObject, &Fcb, &Ccb );
//
// Use a try-finally to facilitate cleanup.
//
try {
//
// We only support query on file and directory handles.
//
switch (TypeOfOpen) {
case UserDirectoryOpen :
case UserFileOpen :
//
// Acquire shared access to this file. NOTE that this could be
// a recursive acquire, if we already preacquired in
// CdAcquireForCreateSection().
//
CdAcquireFileShared( IrpContext, Fcb );
ReleaseFcb = TRUE;
//
// Make sure we have the correct sizes for a directory.
//
if (!FlagOn( Fcb->FcbState, FCB_STATE_INITIALIZED )) {
ASSERT( TypeOfOpen == UserDirectoryOpen );
CdVerifyOrCreateDirStreamFile( IrpContext, Fcb);
}
//
// Make sure the Fcb is in a usable condition. This will raise
// an error condition if the volume is unusable
//
CdVerifyFcbOperation( IrpContext, Fcb );
//
// Based on the information class we'll do different
// actions. Each of hte procedures that we're calling fills
// up the output buffer, if possible. They will raise the
// status STATUS_BUFFER_OVERFLOW for an insufficient buffer.
// This is considered a somewhat unusual case and is handled
// more cleanly with the exception mechanism rather than
// testing a return status value for each call.
//
switch (FileInformationClass) {
case FileAllInformation:
//
// We don't allow this operation on a file opened by file Id.
//
if (FlagOn( Ccb->Flags, CCB_FLAG_OPEN_BY_ID )) {
Status = STATUS_INVALID_PARAMETER;
break;
}
//
// In this case go ahead and call the individual routines to
// fill in the buffer. Only the name routine will
// pointer to the output buffer and then call the
// individual routines to fill in the buffer.
//
Length -= (sizeof( FILE_ACCESS_INFORMATION ) +
sizeof( FILE_MODE_INFORMATION ) +
sizeof( FILE_ALIGNMENT_INFORMATION ));
CdQueryBasicInfo( IrpContext, Fcb, &Buffer->BasicInformation, &Length );
CdQueryStandardInfo( IrpContext, Fcb, &Buffer->StandardInformation, &Length );
CdQueryInternalInfo( IrpContext, Fcb, &Buffer->InternalInformation, &Length );
CdQueryEaInfo( IrpContext, Fcb, &Buffer->EaInformation, &Length );
CdQueryPositionInfo( IrpContext, IrpSp->FileObject, &Buffer->PositionInformation, &Length );
Status = CdQueryNameInfo( IrpContext, IrpSp->FileObject, &Buffer->NameInformation, &Length );
break;
case FileBasicInformation:
CdQueryBasicInfo( IrpContext, Fcb, (PFILE_BASIC_INFORMATION) Buffer, &Length );
break;
case FileStandardInformation:
CdQueryStandardInfo( IrpContext, Fcb, (PFILE_STANDARD_INFORMATION) Buffer, &Length );
break;
case FileInternalInformation:
CdQueryInternalInfo( IrpContext, Fcb, (PFILE_INTERNAL_INFORMATION) Buffer, &Length );
break;
case FileEaInformation:
CdQueryEaInfo( IrpContext, Fcb, (PFILE_EA_INFORMATION) Buffer, &Length );
break;
case FilePositionInformation:
CdQueryPositionInfo( IrpContext, IrpSp->FileObject, (PFILE_POSITION_INFORMATION) Buffer, &Length );
break;
case FileNameInformation:
//
// We don't allow this operation on a file opened by file Id.
//
if (!FlagOn( Ccb->Flags, CCB_FLAG_OPEN_BY_ID )) {
Status = CdQueryNameInfo( IrpContext, IrpSp->FileObject, (PFILE_NAME_INFORMATION) Buffer, &Length );
} else {
Status = STATUS_INVALID_PARAMETER;
}
break;
case FileAlternateNameInformation:
if (!FlagOn( Ccb->Flags, CCB_FLAG_OPEN_BY_ID )) {
Status = CdQueryAlternateNameInfo( IrpContext, Fcb, Ccb, (PFILE_NAME_INFORMATION) Buffer, &Length );
} else {
Status = STATUS_INVALID_PARAMETER;
}
break;
case FileNetworkOpenInformation:
CdQueryNetworkInfo( IrpContext, Fcb, (PFILE_NETWORK_OPEN_INFORMATION) Buffer, &Length );
break;
default :
Status = STATUS_INVALID_PARAMETER;
}
break;
default :
Status = STATUS_INVALID_PARAMETER;
}
//
// Set the information field to the number of bytes actually filled in
// and then complete the request
//
Irp->IoStatus.Information = IrpSp->Parameters.QueryFile.Length - Length;
} finally {
//
// Release the file.
//
if (ReleaseFcb) {
#pragma prefast( suppress: 28107, "prefast cannot work out that the Fcb is acquired by this point.")
CdReleaseFile( IrpContext, Fcb );
}
}
//
// Complete the request if we didn't raise.
//
CdCompleteRequest( IrpContext, Irp, Status );
return Status;
}
__drv_mustHoldCriticalRegion
VOID
CdLookupAllocation (
__in PIRP_CONTEXT IrpContext,
__in PFCB Fcb,
__in LONGLONG FileOffset,
__out PLONGLONG DiskOffset,
__out PULONG ByteCount
)
/*++
Routine Description:
This routine looks through the mapping information for the file
to find the logical diskoffset and number of bytes at that offset.
We only deal with logical 2048 byte sectors here.
If the mapping isn't present we will look it up on disk now.
This routine assumes we are looking up a valid range in the file. This
routine raises if it can't find mapping for the file offset.
The Fcb may not be locked prior to calling this routine. We will always
acquire it here.
Arguments:
Fcb - Fcb representing this stream.
FileOffset - Lookup the allocation beginning at this point.
DiskOffset - Address to store the logical disk offset.
ByteCount - Address to store the number of contiguous bytes beginning
at DiskOffset above.
Return Value:
None.
--*/
{
BOOLEAN FirstPass = TRUE;
ULONG McbEntryOffset;
PFCB ParentFcb = NULL;
BOOLEAN CleanupParent = FALSE;
BOOLEAN UnlockFcb = FALSE;
LONGLONG CurrentFileOffset;
ULONG CurrentMcbOffset;
PCD_MCB_ENTRY CurrentMcbEntry;
DIRENT_ENUM_CONTEXT DirContext = {0};
DIRENT Dirent = {0};
PAGED_CODE();
ASSERT_IRP_CONTEXT( IrpContext );
ASSERT_FCB( Fcb );
//
// For DASD IO we already have clamped the read to the volume limits.
// We'll allow reading beyond those limits for extended DASD IO, so
// no MCB lookup here.
//
if (Fcb == Fcb->Vcb->VolumeDasdFcb) {
*DiskOffset = FileOffset;
return;
}
//
// Use a try finally to facilitate cleanup.
//
try {
//
// We use a loop to perform the lookup. If we don't find the mapping in the
// first pass then we look up all of the allocation and then look again.
while (TRUE) {
//
//
// Lookup the entry containing this file offset.
//
CdLockFcb( IrpContext, Fcb );
UnlockFcb = TRUE;
McbEntryOffset = CdFindMcbEntry( IrpContext, Fcb, FileOffset );
//
// If within the Mcb then we use the data out of this entry and are
// done.
//
if (McbEntryOffset < Fcb->Mcb.CurrentEntryCount) {
CdDiskOffsetFromMcbEntry( IrpContext,
Fcb->Mcb.McbArray + McbEntryOffset,
FileOffset,
DiskOffset,
ByteCount );
break;
//
// If this is not the first pass then the disk is corrupt.
//
} else if (!FirstPass) {
CdRaiseStatus( IrpContext, STATUS_DISK_CORRUPT_ERROR );
}
CdUnlockFcb( IrpContext, Fcb );
UnlockFcb = FALSE;
//
// Initialize the search dirent structures.
//
CdInitializeDirContext( IrpContext, &DirContext );
CdInitializeDirent( IrpContext, &Dirent );
//
// Otherwise we need to walk the dirents for this file until we find
// the one containing this entry. The parent Fcb should always be
// present.
//
ParentFcb = Fcb->ParentFcb;
CdAcquireFileShared( IrpContext, ParentFcb );
CleanupParent = TRUE;
//
// Do an unsafe test to see if we need to create a file object.
//
CdVerifyOrCreateDirStreamFile( IrpContext, ParentFcb);
//
// Initialize the local variables to indicate the first dirent
// and lookup the first dirent.
//
CurrentFileOffset = 0;
CurrentMcbOffset = 0;
CdLookupDirent( IrpContext,
ParentFcb,
CdQueryFidDirentOffset( Fcb->FileId ),
&DirContext );
//
// If we are adding allocation to the Mcb then add all of it.
//
while (TRUE ) {
//
// Update the dirent from the on-disk dirent.
//
CdUpdateDirentFromRawDirent( IrpContext, ParentFcb, &DirContext, &Dirent );
//
// Add this dirent to the Mcb if not already present.
//
CdLockFcb( IrpContext, Fcb );
UnlockFcb = TRUE;
if (CurrentMcbOffset >= Fcb->Mcb.CurrentEntryCount) {
CdAddAllocationFromDirent( IrpContext, Fcb, CurrentMcbOffset, CurrentFileOffset, &Dirent );
}
CdUnlockFcb( IrpContext, Fcb );
UnlockFcb = FALSE;
//
// If this is the last dirent for the file then exit.
//
if (!FlagOn( Dirent.DirentFlags, CD_ATTRIBUTE_MULTI )) {
break;
}
//
// If we couldn't find another entry then the directory is corrupt because
// the last dirent for a file doesn't exist.
//
if (!CdLookupNextDirent( IrpContext, ParentFcb, &DirContext, &DirContext )) {
CdRaiseStatus( IrpContext, STATUS_DISK_CORRUPT_ERROR );
}
//
// Update our loop variables.
//
CurrentMcbEntry = Fcb->Mcb.McbArray + CurrentMcbOffset;
CurrentFileOffset += CurrentMcbEntry->ByteCount;
CurrentMcbOffset += 1;
}
//
// All of the allocation is loaded. Go back and look up the mapping again.
// It better be there this time.
//
FirstPass = FALSE;
}
} finally {
if (CleanupParent) {
//
// Release the parent and cleanup the dirent structures.
//
CdReleaseFile( IrpContext, ParentFcb );
CdCleanupDirContext( IrpContext, &DirContext );
CdCleanupDirent( IrpContext, &Dirent );
}
if (UnlockFcb) { CdUnlockFcb( IrpContext, Fcb ); }
}
return;
}
