请问tooflat大侠的这段代码有什么问题?

楼主^#

更多发布于：2007-03-14 13:08

我把tooflat大侠read例程skip掉就一切正常,如果不skip打开大的word文档就会出现第一页的内容,然后就马上黑屏死机,不知道是哪里出问题了,请指点指点!

NTSTATUS
SfRead(
   IN PDEVICE_OBJECT DeviceObject,
   IN PIRP Irp
   )
{
   PSFILTER_DEVICE_EXTENSION DevExt = (PSFILTER_DEVICE_EXTENSION) DeviceObject->DeviceExtension;
   PIO_STACK_LOCATION IrpSp = IoGetCurrentIrpStackLocation(Irp);
   PFILE_OBJECT FileObject = IrpSp->FileObject;
   PREAD_WRITE_COMPLETION_CONTEXT CompletionCtx = NULL;
   PVOID OldBuffer = NULL;
   PMDL Mdl = NULL;
   PVOID MyBuffer = NULL;
   ULONG Length = 0;
   FILE_CONTEXT_HDR FileCtxHdr;
   PFILE_CONTEXT FileCtxPtr = NULL;
   NTSTATUS Status = STATUS_SUCCESS;

   PAGED_CODE();

   //
   // Sfilter doesn't allow handles to its control device object to be created,
   // therefore, no other operation should be able to come through.
   //
   //ASSERT(!IS_MY_CONTROL_DEVICE_OBJECT(DeviceObject));
   if (IS_MY_CONTROL_DEVICE_OBJECT(DeviceObject))
   {
   //
   // TFilter doesn't allow for any communication through its control
   // device object, therefore it fails all requests to open a handle
   // to its control device object.
   //
   // See the FileSpy sample for an example of how to allow creates to
   // the filter's control device object and manage communication via
   // that handle.
   //
   Irp->IoStatus.Status = STATUS_INVALID_DEVICE_REQUEST;
   Irp->IoStatus.Information = 0;

   IoCompleteRequest( Irp, IO_NO_INCREMENT );

   return STATUS_INVALID_DEVICE_REQUEST;
   }
   ASSERT(IS_MY_DEVICE_OBJECT(DeviceObject));

   //
   // We only care about volume filter device object
   //
   if (!DevExt->StorageStackDeviceObject)
   {
   IoSkipCurrentIrpStackLocation(Irp);
   return IoCallDriver(DevExt->AttachedToDeviceObject, Irp);
   }

#if DBG
   if (DevExt->DriveLetter == DEBUG_VOLUME)
   {
   IoSkipCurrentIrpStackLocation(Irp);
   return IoCallDriver(DevExt->AttachedToDeviceObject, Irp);
   }
#endif

   if (!(Irp->Flags & (IRP_NOCACHE | IRP_PAGING_IO | IRP_SYNCHRONOUS_PAGING_IO)))
   {
   IoSkipCurrentIrpStackLocation(Irp);
   return IoCallDriver(DevExt->AttachedToDeviceObject, Irp);
   }
   if (1) //如果有这个条件就不会死机
   {
   IoSkipCurrentIrpStackLocation(Irp);
   return IoCallDriver(DevExt->AttachedToDeviceObject, Irp);
   }

   ExAcquireFastMutex(&DevExt->FsCtxTableMutex);

   FileCtxHdr.FsContext = FileObject->FsContext;
   FileCtxPtr = RtlLookupElementGenericTable(&DevExt->FsCtxTable, &FileCtxHdr);

   ExReleaseFastMutex(&DevExt->FsCtxTableMutex);

   if (!FileCtxPtr || !FileCtxPtr->DecryptOnRead)
   {
   IoSkipCurrentIrpStackLocation(Irp);
   return IoCallDriver(DevExt->AttachedToDeviceObject, Irp);
   }

   do
   {
   Length = IrpSp->Parameters.Read.Length;

   if (Irp->MdlAddress)
   {
   OldBuffer = MmGetSystemAddressForMdl(Irp->MdlAddress);
   }
   else
   {
   Mdl = IoAllocateMdl(Irp->UserBuffer, Length, FALSE, FALSE, NULL);
   if (Mdl == NULL)
   {
   KdPrint(("sfilter!SfRead: IoAllocateMdl failed\n"));
   Status = STATUS_INSUFFICIENT_RESOURCES;
   break;
   }

   try
   {
   MmProbeAndLockPages(Mdl, Irp->RequestorMode, IoWriteAccess);
   }
   except (EXCEPTION_EXECUTE_HANDLER)
   {
   KdPrint(("sfilter!SfRead: STATUS_INVALID_USER_BUFFER\n"));
   IoFreeMdl(Mdl);
   Status = STATUS_INVALID_USER_BUFFER;
   break;
   }

   OldBuffer = MmGetSystemAddressForMdl(Mdl);
   }

   if (!OldBuffer)
   {
   KdPrint(("sfilter!SfRead: STATUS_INVALID_PARAMETER\n"));
   if (Mdl)
   {
   MmUnlockPages(Mdl);
   IoFreeMdl(Mdl);
   }
   Status = STATUS_INVALID_PARAMETER;
   break;
   }

   CompletionCtx = ExAllocateFromNPagedLookasideList(&gReadWriteCompletionCtxLookAsideList);
   if (!CompletionCtx)
   {
   KdPrint(("sfilter!SfRead: STATUS_INSUFFICIENT_RESOURCES\n"));
   if (Mdl)
   {
   MmUnlockPages(Mdl);
   IoFreeMdl(Mdl);
   }
   Status = STATUS_INSUFFICIENT_RESOURCES;
   break;
   }

   MyBuffer = ExAllocatePoolWithTag(NonPagedPool, IrpSp->Parameters.Write.Length, SFLT_POOL_TAG);
   RtlZeroMemory(MyBuffer,IrpSp->Parameters.Write.Length);

   if (!MyBuffer)
   {
   KdPrint(("sfilter!SfRead: STATUS_INSUFFICIENT_RESOURCES\n"));
   if (Mdl)
   {
   MmUnlockPages(Mdl);
   IoFreeMdl(Mdl);
   }
   ExFreePool(CompletionCtx);
   Status = STATUS_INSUFFICIENT_RESOURCES;
   break;
   }

   CompletionCtx->OldMdl = Irp->MdlAddress;
   CompletionCtx->OldUserBuffer = Irp->UserBuffer;
   CompletionCtx->OldSystemBuffer = Irp->AssociatedIrp.SystemBuffer;

   CompletionCtx->MdlForUserBuffer = Mdl;

   CompletionCtx->OldBuffer = OldBuffer;
   CompletionCtx->MyBuffer = MyBuffer;
   CompletionCtx->Length = Length;

   Irp->MdlAddress = IoAllocateMdl(MyBuffer, IrpSp->Parameters.Read.Length, FALSE, TRUE, NULL);
   if (!Irp->MdlAddress)
   {
   KdPrint(("sfilter!SfRead: STATUS_INSUFFICIENT_RESOURCES\n"));
   Irp->MdlAddress = CompletionCtx->OldMdl;
   if (Mdl)
   {
   MmUnlockPages(Mdl);
   IoFreeMdl(Mdl);
   }
   ExFreePool(CompletionCtx);
   ExFreePool(MyBuffer);
   Status = STATUS_INSUFFICIENT_RESOURCES;
   break;
   }

   //KdPrint(("sfilter!SfRead: Decrypt %ws\n", FileCtxPtr->Name));

   MmBuildMdlForNonPagedPool(Irp->MdlAddress);
   Irp->UserBuffer = MmGetMdlVirtualAddress(Irp->MdlAddress);

   IoCopyCurrentIrpStackLocationToNext(Irp);
   IoSetCompletionRoutine(Irp, SfReadCompletion, CompletionCtx, TRUE, TRUE,TRUE);

   return IoCallDriver(DevExt->AttachedToDeviceObject, Irp);

   } while (FALSE);

   Irp->IoStatus.Status = Status;
   IoCompleteRequest(Irp, IO_NO_INCREMENT);

   return Status;
}

NTSTATUS
SfReadCompletion(
   IN PDEVICE_OBJECT DeviceObject,
   IN PIRP Irp,
   IN PVOID Context
   )
{
   PREAD_WRITE_COMPLETION_CONTEXT CompletionCtx = (PREAD_WRITE_COMPLETION_CONTEXT) Context;
   PSFILTER_DEVICE_EXTENSION DevExt = (PSFILTER_DEVICE_EXTENSION) DeviceObject->DeviceExtension;
   PIO_STACK_LOCATION IrpSp = IoGetCurrentIrpStackLocation(Irp);
   PFILE_OBJECT FileObject = IrpSp->FileObject;
   FILE_CONTEXT_HDR FileCtxHdr;
   PFILE_CONTEXT FileCtxPtr = NULL;
   ULONG Offset = 0;
   NTSTATUS Status = STATUS_SUCCESS;
   ULONG i=0;

   UNREFERENCED_PARAMETER(DeviceObject);

   if (Irp->PendingReturned)
   IoMarkIrpPending(Irp);

   IoFreeMdl(Irp->MdlAddress);

   Irp->MdlAddress = CompletionCtx->OldMdl;
   Irp->UserBuffer = CompletionCtx->OldUserBuffer;
   Irp->AssociatedIrp.SystemBuffer = CompletionCtx->OldSystemBuffer;


   for (Offset = 0; Offset < CompletionCtx->Length; ++Offset)
   {
   ((PUCHAR) CompletionCtx->OldBuffer)[Offset] = ((PUCHAR) CompletionCtx->MyBuffer)[Offset];
   }

   if (CompletionCtx->MdlForUserBuffer)
   {
   MmUnlockPages(CompletionCtx->MdlForUserBuffer);
   IoFreeMdl(CompletionCtx->MdlForUserBuffer);
   }

   ExFreePoolWithTag(CompletionCtx->MyBuffer, SFLT_POOL_TAG);
   ExFreeToNPagedLookasideList(&gReadWriteCompletionCtxLookAsideList, CompletionCtx);

   return STATUS_SUCCESS;
}

喜欢1

最新喜欢：

Leopar...

lsxredrain 驱动中牛注册日期2006-08-31 最后登录2008-10-18 粉丝1 关注0 积分540分威望421点贡献值1点好评度420点原创分4分专家分0分加关注写私信	沙发^# 发布于：2007-03-15 10:45 主要还是ms office引起的,不知道有什么好的解决办法?
	回复(0) 喜欢(0)

lsxredrain

驱动中牛

注册日期2006-08-31
最后登录2008-10-18
粉丝1
关注0
积分540分
威望421点
贡献值1点
好评度420点
原创分4分
专家分0分

加关注写私信

板凳^#

发布于：2007-03-15 14:50

691.016 Default sfilter!SfRead: Decrypt D:\kkkd\~WRD0002.tmp
691.016 Default sfilter!SfRead: Decrypt ((PFSRTL_COMMON_FCB_HEADER)FileObject->FsContext)->FileSize.QuadPart = 6144
691.016 Default sfilter!SfRead: Decrypt ((PFSRTL_COMMON_FCB_HEADER)FileObject->FsContext)->ValidDataLength.QuadPart = 0

H in MSGR3SC.DLL

692.719 Default sfilter!SfWrite:!!! Encrypt D:\kkkd\~WRL0005.tmp
692.719 Default sfilter!SfWrite: Encrypt ((PFSRTL_COMMON_FCB_HEADER)FileObject->FsContext)->FileSize.QuadPart = 0
692.719 Default sfilter!SfWrite: Encrypt ((PFSRTL_COMMON_FCB_HEADER)FileObject->FsContext)->ValidDataLength.QuadPart = 0
692.719 Default sfilter!SfWrite: Encrypt FileObject->CurrentByteOffset.LowPart = 23040
692.813 Default SFilter!SioctlDeviceControl 压缩前长度 CompressDataLen = 509
692.828 Default SFilter!SioctlDeviceControl 压缩后长度 CompressDataLen = 62
692.828 Default lsx KeClearEvent gpEventObject sussfully!
692.828 Default sfilter!SfWrite: 开始添加加密标记 Encrypt D:\kkkd\~WRL0005.tmp need compress!
692.828 Default lsx CompressWaitEvent sussfully!

回复喜欢

lsxredrain

驱动中牛

注册日期2006-08-31
最后登录2008-10-18
粉丝1
关注0
积分540分
威望421点
贡献值1点
好评度420点
原创分4分
专家分0分

加关注写私信

地板^#

发布于：2007-03-15 14:52

fCreate: FileName = D:\kkkd\lsx.doc
693.719 Default sfilter!SfWrite:!!! Encrypt D:\DOCUME~1\lsx\LOCALS~1\Temp\~WRS0004.tmp
693.719 Default sfilter!SfWrite: Encrypt ((PFSRTL_COMMON_FCB_HEADER)FileObject->FsContext)->FileSize.QuadPart = 0
693.719 Default sfilter!SfWrite: Encrypt ((PFSRTL_COMMON_FCB_HEADER)FileObject->FsContext)->ValidDataLength.QuadPart = 0
693.719 Default sfilter!SfWrite: Encrypt FileObject->CurrentByteOffset.LowPart = 5254
693.797 Default SFilter!SioctlDeviceControl 压缩前长度 CompressDataLen = 509
693.813 Default SFilter!SioctlDeviceControl 压缩后长度 CompressDataLen = 29
693.813 Default lsx KeClearEvent gpEventObject sussfully!
693.813 Default sfilter!SfWrite: 开始添加加密标记 Encrypt D:\DOCUME~1\lsx\LOCALS~1\Temp\~WRS0004.tmp need compress!
693.813 Default lsx CompressWaitEvent sussfully!

回复喜欢

lsxredrain 驱动中牛注册日期2006-08-31 最后登录2008-10-18 粉丝1 关注0 积分540分威望421点贡献值1点好评度420点原创分4分专家分0分加关注写私信	地下室^# 发布于：2007-03-15 14:55 当((PFSRTL_COMMON_FCB_HEADER)FileObject->FsContext)->FileSize.QuadPart 为0时,为什么FileObject->CurrentByteOffset.LowPart 不为零?,如果只想对文件头512个字节进行处理,需要根据什么来判断文件指针偏移位置才是正确的?
	回复(0) 喜欢(0)

您需要登录后才可以回帖，登录或者注册