filedisk.c

功能齐全的虚拟磁盘驱动

        device_extension->terminate_thread = TRUE;

        KeSetEvent(
            &device_extension->request_event,
            (KPRIORITY) 0,
            FALSE
            );

        IoDeleteDevice(device_object);

        return status;
    }

    ZwClose(thread_handle);

    return STATUS_SUCCESS;
}

#pragma code_seg("PAGE")

VOID
FileDiskUnload (//卸载驱动，删除设备，关闭打开的文件等等。
    IN PDRIVER_OBJECT DriverObject
    )
{
    PDEVICE_OBJECT device_object;

    PAGED_CODE();

    device_object = DriverObject->DeviceObject;

    while (device_object)
    {
        device_object = FileDiskDeleteDevice(device_object);
    }

    ZwClose(dir_handle);
}
//保证每一次操作完成。
PDEVICE_OBJECT
FileDiskDeleteDevice (
    IN PDEVICE_OBJECT DeviceObject
    )
{
    PDEVICE_EXTENSION   device_extension;
    PDEVICE_OBJECT      next_device_object;

    PAGED_CODE();

    ASSERT(DeviceObject != NULL);

    device_extension = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;

    device_extension->terminate_thread = TRUE;

    KeSetEvent(
        &device_extension->request_event,
        (KPRIORITY) 0,
        FALSE
        );

    KeWaitForSingleObject(
        device_extension->thread_pointer,
        Executive,
        KernelMode,
        FALSE,
        NULL
        );

    ObDereferenceObject(device_extension->thread_pointer);

    if (device_extension->security_client_context != NULL)
    {
        SeDeleteClientSecurity(device_extension->security_client_context);
        ExFreePool(device_extension->security_client_context);
    }

    next_device_object = DeviceObject->NextDevice;

    IoDeleteDevice(DeviceObject);

    return next_device_object;
}

NTSTATUS
FileDiskCreateClose (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
//PAGED_CODE()是一个调试用的宏。如果一个函数被定义在可分页交换的段中，那么它执行时的中断级别必须满足一定的要求。
    PAGED_CODE();
//下面是经典模式，没什么好说的
    Irp->IoStatus.Status = STATUS_SUCCESS;
    Irp->IoStatus.Information = FILE_OPENED;

    IoCompleteRequest(Irp, IO_NO_INCREMENT);

    return STATUS_SUCCESS;
}

#pragma code_seg()

NTSTATUS
FileDiskReadWrite (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION   device_extension;
    PIO_STACK_LOCATION  io_stack;
//得到扩展设备
    device_extension = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;
//判断是否有物理设备。没有打开文件，就返回失败
    if (!device_extension->media_in_device)
    {
        Irp->IoStatus.Status = STATUS_NO_MEDIA_IN_DEVICE;
        Irp->IoStatus.Information = 0;

        IoCompleteRequest(Irp, IO_NO_INCREMENT);

        return STATUS_NO_MEDIA_IN_DEVICE;
    }

    io_stack = IoGetCurrentIrpStackLocation(Irp);
//  读0长的时候立刻成功
    if (io_stack->Parameters.Read.Length == 0)
    {
        Irp->IoStatus.Status = STATUS_SUCCESS;
        Irp->IoStatus.Information = 0;

        IoCompleteRequest(Irp, IO_NO_INCREMENT);

        return STATUS_SUCCESS;
    }
//放入队列里面去
    IoMarkIrpPending(Irp);
 // 把请求写入链表
    ExInterlockedInsertTailList(
        &device_extension->list_head,
        &Irp->Tail.Overlay.ListEntry,
        &device_extension->list_lock
        );
// 设置事件。让线程循环运行。
    KeSetEvent(
        &device_extension->request_event,
        (KPRIORITY) 0,
        FALSE
        );

    return STATUS_PENDING;
}

NTSTATUS
FileDiskDeviceControl (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION   device_extension;
    PIO_STACK_LOCATION  io_stack;
    NTSTATUS            status;
// 得到设备扩展
    device_extension = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;

// 得到当前设备栈
    io_stack = IoGetCurrentIrpStackLocation(Irp);
// 判断如果是还没有加载物理媒质就返回失败。但是
// IOCTL_FILE_DISK_OPEN_FILE是自定义的功能号，专
// 用来加载物理媒质的
    if (!device_extension->media_in_device &&
        io_stack->Parameters.DeviceIoControl.IoControlCode !=
        IOCTL_FILE_DISK_OPEN_FILE)
    {
        Irp->IoStatus.Status = STATUS_NO_MEDIA_IN_DEVICE;
        Irp->IoStatus.Information = 0;

        IoCompleteRequest(Irp, IO_NO_INCREMENT);

        return STATUS_NO_MEDIA_IN_DEVICE;
    }
// 根据不同的功能号处理...
    switch (io_stack->Parameters.DeviceIoControl.IoControlCode)
    {
    case IOCTL_FILE_DISK_OPEN_FILE:
        {
            SECURITY_QUALITY_OF_SERVICE security_quality_of_service;

            if (device_extension->media_in_device)
            {
                KdPrint(("FileDisk: IOCTL_FILE_DISK_OPEN_FILE: Media already opened\n"));

                status = STATUS_INVALID_DEVICE_REQUEST;
                Irp->IoStatus.Information = 0;
                break;
            }

            if (io_stack->Parameters.DeviceIoControl.InputBufferLength <
                sizeof(OPEN_FILE_INFORMATION))
            {
                status = STATUS_INVALID_PARAMETER;
                Irp->IoStatus.Information = 0;
                break;
            }

            if (io_stack->Parameters.DeviceIoControl.InputBufferLength <
                sizeof(OPEN_FILE_INFORMATION) +
                ((POPEN_FILE_INFORMATION)Irp->AssociatedIrp.SystemBuffer)->FileNameLength -
                sizeof(UCHAR))
            {
                status = STATUS_INVALID_PARAMETER;
                Irp->IoStatus.Information = 0;
                break;
            }

            if (device_extension->security_client_context != NULL)
            {
                SeDeleteClientSecurity(device_extension->security_client_context);
            }
            else
            {
                device_extension->security_client_context =
                    ExAllocatePool(NonPagedPool, sizeof(SECURITY_CLIENT_CONTEXT));
            }

            RtlZeroMemory(&security_quality_of_service, sizeof(SECURITY_QUALITY_OF_SERVICE));

            security_quality_of_service.Length = sizeof(SECURITY_QUALITY_OF_SERVICE);
            security_quality_of_service.ImpersonationLevel = SecurityImpersonation;
            security_quality_of_service.ContextTrackingMode = SECURITY_STATIC_TRACKING;
            security_quality_of_service.EffectiveOnly = FALSE;

            SeCreateClientSecurity(
                PsGetCurrentThread(),
                &security_quality_of_service,
                FALSE,
                device_extension->security_client_context
                );

            IoMarkIrpPending(Irp);

            ExInterlockedInsertTailList(
                &device_extension->list_head,
                &Irp->Tail.Overlay.ListEntry,
                &device_extension->list_lock
                );

            KeSetEvent(
                &device_extension->request_event,
                (KPRIORITY) 0,
                FALSE
                );

            status = STATUS_PENDING;

            break;
        }

    case IOCTL_FILE_DISK_CLOSE_FILE:
        {
            IoMarkIrpPending(Irp);

            ExInterlockedInsertTailList(
                &device_extension->list_head,
                &Irp->Tail.Overlay.ListEntry,
                &device_extension->list_lock
                );

            KeSetEvent(
                &device_extension->request_event,
                (KPRIORITY) 0,
                FALSE
                );

            status = STATUS_PENDING;

            break;
        }

    case IOCTL_FILE_DISK_QUERY_FILE:
        {
            POPEN_FILE_INFORMATION open_file_information;

            if (io_stack->Parameters.DeviceIoControl.OutputBufferLength <
                sizeof(OPEN_FILE_INFORMATION) + device_extension->file_name.Length - sizeof(UCHAR))
            {
                status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }

            open_file_information = (POPEN_FILE_INFORMATION) Irp->AssociatedIrp.SystemBuffer;

            open_file_information->FileSize.QuadPart = device_extension->file_size.QuadPart;
            open_file_information->ReadOnly = device_extension->read_only;
            open_file_information->FileNameLength = device_extension->file_name.Length;

            RtlCopyMemory(
                open_file_information->FileName,
                device_extension->file_name.Buffer,
                device_extension->file_name.Length
                );

            status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(OPEN_FILE_INFORMATION) +
                open_file_information->FileNameLength - sizeof(UCHAR);

            break;
        }

    case IOCTL_DISK_CHECK_VERIFY:
    case IOCTL_CDROM_CHECK_VERIFY:
    case IOCTL_STORAGE_CHECK_VERIFY:
    case IOCTL_STORAGE_CHECK_VERIFY2:
        {
            status = STATUS_SUCCESS;
            Irp->IoStatus.Information = 0;
            break;
        }

    case IOCTL_DISK_GET_DRIVE_GEOMETRY:
    case IOCTL_CDROM_GET_DRIVE_GEOMETRY:
        {
            PDISK_GEOMETRY  disk_geometry;
            ULONGLONG       length;

            if (io_stack->Parameters.DeviceIoControl.OutputBufferLength <
                sizeof(DISK_GEOMETRY))
            {
                status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }

            disk_geometry = (PDISK_GEOMETRY) Irp->AssociatedIrp.SystemBuffer;

            length = device_extension->file_size.QuadPart;

            disk_geometry->Cylinders.QuadPart = length / SECTOR_SIZE / 32 / 2;
            disk_geometry->MediaType = FixedMedia;
            disk_geometry->TracksPerCylinder = 2;
            disk_geometry->SectorsPerTrack = 32;
            disk_geometry->BytesPerSector = SECTOR_SIZE;

            status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(DISK_GEOMETRY);

            break;
        }

    case IOCTL_DISK_GET_LENGTH_INFO:
        {
            PGET_LENGTH_INFORMATION get_length_information;

            if (io_stack->Parameters.DeviceIoControl.OutputBufferLength <
                sizeof(GET_LENGTH_INFORMATION))
            {
                status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }

            get_length_information = (PGET_LENGTH_INFORMATION) Irp->AssociatedIrp.SystemBuffer;

            get_length_information->Length.QuadPart = device_extension->file_size.QuadPart;

            status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(GET_LENGTH_INFORMATION);

        break;
        }

    case IOCTL_DISK_GET_PARTITION_INFO:
        {
            PPARTITION_INFORMATION  partition_information;
            ULONGLONG               length;

            if (io_stack->Parameters.DeviceIoControl.OutputBufferLength <
                sizeof(PARTITION_INFORMATION))
            {
                status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }

            partition_information = (PPARTITION_INFORMATION) Irp->AssociatedIrp.SystemBuffer;

            length = device_extension->file_size.QuadPart;

            partition_information->StartingOffset.QuadPart = 0;
            partition_information->PartitionLength.QuadPart = length;
            partition_information->HiddenSectors = 1;
            partition_information->PartitionNumber = 0;
            partition_information->PartitionType = 0;
            partition_information->BootIndicator = FALSE;
            partition_information->RecognizedPartition = FALSE;
            partition_information->RewritePartition = FALSE;

            status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(PARTITION_INFORMATION);

            break;
        }

    case IOCTL_DISK_GET_PARTITION_INFO_EX:
        {
            PPARTITION_INFORMATION_EX   partition_information_ex;
            ULONGLONG                   length;

            if (io_stack->Parameters.DeviceIoControl.OutputBufferLength <
                sizeof(PARTITION_INFORMATION_EX))
            {
                status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }

            partition_information_ex = (PPARTITION_INFORMATION_EX) Irp->AssociatedIrp.SystemBuffer;

            length = device_extension->file_size.QuadPart;

            partition_information_ex->PartitionStyle = PARTITION_STYLE_MBR;
            partition_information_ex->StartingOffset.QuadPart = 0;
            partition_information_ex->PartitionLength.QuadPart = length;
            partition_information_ex->PartitionNumber = 0;
            partition_information_ex->RewritePartition = FALSE;
            partition_information_ex->Mbr.PartitionType = 0;
            partition_information_ex->Mbr.BootIndicator = FALSE;
            partition_information_ex->Mbr.RecognizedPartition = FALSE;
            partition_information_ex->Mbr.HiddenSectors = 1;

            status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(PARTITION_INFORMATION_EX);

            break;
        }

    case IOCTL_DISK_IS_WRITABLE:
        {
            if (!device_extension->read_only)
            {
                status = STATUS_SUCCESS;
            }
            else
            {
                status = STATUS_MEDIA_WRITE_PROTECTED;
            }
            Irp->IoStatus.Information = 0;
            break;
        }

    case IOCTL_DISK_MEDIA_REMOVAL:
    case IOCTL_STORAGE_MEDIA_REMOVAL:
        {
            status = STATUS_SUCCESS;
            Irp->IoStatus.Information = 0;
            break;
        }

    case IOCTL_CDROM_READ_TOC:
        {
            PCDROM_TOC cdrom_toc;

            if (io_stack->Parameters.DeviceIoControl.OutputBufferLength <
                sizeof(CDROM_TOC))
            {
                status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }

            cdrom_toc = (PCDROM_TOC) Irp->AssociatedIrp.SystemBuffer;

            RtlZeroMemory(cdrom_toc, sizeof(CDROM_TOC));