关于 TrueCrypt 第6集

上一集看 FileDisk 的代码，没看出个所以然……
本集继续……

看下 FileDisk 的应用层 Mount 时的实现代码

int  FileDiskMount( int  DeviceNumber, POPEN_FILE_INFORMATION  OpenFileInformation,  char  DriveLetter, BOOLEAN CdImage)
{
    char    VolumeName[] = "\\\\.\\ :";
    char    DeviceName[255];
    HANDLE  Device;
    DWORD   BytesReturned;
    VolumeName[4] = DriveLetter;
    Device = CreateFile(
        VolumeName,
        GENERIC_READ | GENERIC_WRITE,
        FILE_SHARE_READ | FILE_SHARE_WRITE,
        NULL,
        OPEN_EXISTING,
        FILE_FLAG_NO_BUFFERING,
        NULL
        );
    if (Device != INVALID_HANDLE_VALUE)
    {
        SetLastError(ERROR_BUSY);
        PrintLastError(&VolumeName[4]);
        return -1;
    }

    if (CdImage)
    {
        sprintf(DeviceName, DEVICE_NAME_PREFIX "Cd" "%u", DeviceNumber);
    }
    else
    {
        sprintf(DeviceName, DEVICE_NAME_PREFIX "%u", DeviceNumber);
    }

    if (!DefineDosDevice(
        DDD_RAW_TARGET_PATH,
        &VolumeName[4],
        DeviceName
        ))
    {
        PrintLastError(&VolumeName[4]);
        return -1;
    }
    else
    {
        printf("DefineDosDevice %s %s \n", &VolumeName[4], DeviceName);        
    }
    
    Device = CreateFile(
        VolumeName,
        GENERIC_READ | GENERIC_WRITE,
        FILE_SHARE_READ | FILE_SHARE_WRITE,
        NULL,
        OPEN_EXISTING,
        FILE_FLAG_NO_BUFFERING,
        NULL
        );
    if (Device == INVALID_HANDLE_VALUE)
    {
        PrintLastError(&VolumeName[4]);
        DefineDosDevice(DDD_REMOVE_DEFINITION, &VolumeName[4], NULL);
        return -1;
    }
    if (!DeviceIoControl(
        Device,
        IOCTL_FILE_DISK_OPEN_FILE,
        OpenFileInformation,
        sizeof(OPEN_FILE_INFORMATION) + OpenFileInformation->FileNameLength - 1,
        NULL,
        0,
        &BytesReturned,
        NULL
        ))
    {
        PrintLastError("FileDisk:");
        DefineDosDevice(DDD_REMOVE_DEFINITION, &VolumeName[4], NULL);
        return -1;
    }
    return 0;
}

在执行 DefineDosDevice() 时，把 传入 DefineDosDevice() 的参数打印出来看一下先……
显示结果：
DefineDosDevice e: \Device\FileDisk\FileDisk0

Mount 成功后，用 Winobj.exe 查看，奇怪的是它并没有在 设备目录 \GLOBAL??\   下面生成一个 e: 的别名

问题：应用层的 DefineDosDevice() 不是相当于 驱动层的 IoCreateSymbolicLink() 函数？ 那为何不会生成 e: 这样的别名，
        没有生成别名，在应用层又是怎么能够直接访问 e: 的呢？
--- 迷惘ing

于是在 FileDiskMount() 函数中增加一些语句尝试一下

int
FileDiskMount(
     int                      DeviceNumber,
    POPEN_FILE_INFORMATION  OpenFileInformation,
     char                     DriveLetter,
    BOOLEAN                 CdImage
)
{
    char    VolumeName[] = "\\\\.\\ :";
    char    DeviceName[255];
    HANDLE  Device;
    DWORD   BytesReturned;
    VolumeName[4] = DriveLetter;
 printf("Enter FileDiskMount \n");
 printf("FileDiskMount CreateFile VolumeName = %s\n", VolumeName);
    Device = CreateFile(
        VolumeName,
        GENERIC_READ | GENERIC_WRITE,
        FILE_SHARE_READ | FILE_SHARE_WRITE,
        NULL,
        OPEN_EXISTING,
        FILE_FLAG_NO_BUFFERING,
        NULL
        );
    if (Device != INVALID_HANDLE_VALUE)
    {
        //  这里没有调用 CloseHandle() 将 Device 关闭 -_-!!
        SetLastError(ERROR_BUSY);
        PrintLastError(&VolumeName[4]);
        return -1;
    }

    if (CdImage)
    {
        sprintf(DeviceName, DEVICE_NAME_PREFIX "Cd" "%u", DeviceNumber);
    }
    else
    {
        sprintf(DeviceName, DEVICE_NAME_PREFIX "%u", DeviceNumber);
    }

 printf("FileDiskMount DefineDosDevice VolumeName = %s DeviceName = %s \n", &VolumeName[4], DeviceName);
    if (!DefineDosDevice(
        DDD_RAW_TARGET_PATH,
        &VolumeName[4],
        DeviceName
        ))
    {
        PrintLastError(&VolumeName[4]);
        return -1;
    }

 printf("FileDiskMount CreateFile VolumeName = %s\n", VolumeName);
    Device = CreateFile(
        VolumeName,
        GENERIC_READ | GENERIC_WRITE,
        FILE_SHARE_READ | FILE_SHARE_WRITE,
        NULL,
        OPEN_EXISTING,
        FILE_FLAG_NO_BUFFERING,
        NULL
        );
    if (Device == INVALID_HANDLE_VALUE)
    {
        PrintLastError(&VolumeName[4]);
        DefineDosDevice(DDD_REMOVE_DEFINITION, &VolumeName[4], NULL);
        return -1;
    }
 if (!DeviceIoControl(
        Device,
        IOCTL_FILE_DISK_OPEN_FILE,
        OpenFileInformation,
        sizeof(OPEN_FILE_INFORMATION) + OpenFileInformation->FileNameLength - 1,
        NULL,
        0,
        &BytesReturned,
        NULL
        ))
    {
        PrintLastError("FileDisk:");
        DefineDosDevice(DDD_REMOVE_DEFINITION, &VolumeName[4], NULL);
        return -1;
    }
 // 在最后 Device 没有进行 CloseHandle() ??
    return 0;
}

运行 filedisk /mount 之后，输出结果如下
Enter FileDiskMount
FileDiskMount CreateFile VolumeName = \\.\e:
FileDiskMount DefineDosDevice VolumeName = e: DeviceName = \Device\FileDisk\FileDisk0
FileDiskMount CreateFile VolumeName = \\.\e:

FileDiskMount 的函数先是 用 CreateFile 尝试打开 \\.\e 这个设备，
确定 e: 这个盘符没有被占用后，就用 DefineDosDevice() 函数 把 e: 这个盘符指向 \Device\FileDisk\FileDisk0 这个设备
接下来，再用 CreateFile 打开 \\.\e 这个设备
然后调用 DeviceIoControl() 给 \\.\e 这个设备发送  IOCTL_FILE_DISK_OPEN_FILE 这个 Control Code

昨天试过用 DeviceIoControl() 函数，但并未显示出设备出来
难道调用 DeviceIoControl() 函数后，还需要向这个设备发 IOCTL_FILE_DISK_OPEN_FILE  这个 Control Code ，
“虚拟的分区”才会显示出来？

于是，决定尝试下，把后来的向设备发送 IOCTL_FILE_DISK_OPEN_FILE 的相关代码去掉，
将 FileDiskMount() 的代码修改为

int
FileDiskMount(
     int                      DeviceNumber,
    POPEN_FILE_INFORMATION  OpenFileInformation,
     char                     DriveLetter,
    BOOLEAN                 CdImage
)
{
    char    VolumeName[] = "\\\\.\\ :";
    char    DeviceName[255];
    HANDLE  Device;
    DWORD   BytesReturned;
    VolumeName[4] = DriveLetter;
 printf("Enter FileDiskMount \n");
 printf("FileDiskMount CreateFile VolumeName = %s\n", VolumeName);
    Device = CreateFile(
        VolumeName,
        GENERIC_READ | GENERIC_WRITE,
        FILE_SHARE_READ | FILE_SHARE_WRITE,
        NULL,
        OPEN_EXISTING,
        FILE_FLAG_NO_BUFFERING,
        NULL
        );
    if (Device != INVALID_HANDLE_VALUE)
    {
        SetLastError(ERROR_BUSY);
        PrintLastError(&VolumeName[4]);
        return -1;
    }
    if (CdImage)
    {
        sprintf(DeviceName, DEVICE_NAME_PREFIX "Cd" "%u", DeviceNumber);
    }
    else
    {
        sprintf(DeviceName, DEVICE_NAME_PREFIX "%u", DeviceNumber);
    }
 printf("FileDiskMount DefineDosDevice VolumeName = %s DeviceName = %s \n", &VolumeName[4], DeviceName);
    if (!DefineDosDevice(
        DDD_RAW_TARGET_PATH,
        &VolumeName[4],
        DeviceName
        ))
    {
        PrintLastError(&VolumeName[4]);
        return -1;
    }
 return 0;
}   

运行结果：
C:\Documents and Settings\test>"C:\Documents and Settings\test\桌面\filediskexe.exe" /mount 0 c:\1.txt 9M e:
Enter FileDiskMount
FileDiskMount CreateFile VolumeName = \\.\e:
FileDiskMount DefineDosDevice VolumeName = e: DeviceName = \Device\FileDisk\File
Disk0

仍然可以在我的电脑里显示 e: 盘这个分区，但双击进入时，会有一个错误提示“无法访问 E:\ 设备未就绪。”

昨天试过调用完 DefineDosDevice() 后，在我的电脑里，还是没有把那个虚拟分区显示出来，为什么 FileDisk 就可以？
将 FileDiskMount() 再修改为

int
FileDiskMount(
     int                      DeviceNumber,
    POPEN_FILE_INFORMATION  OpenFileInformation,
     char                     DriveLetter,
    BOOLEAN                 CdImage
)
{
    char    VolumeName[] = "\\\\.\\ :";
    char    DeviceName[255];
    VolumeName[4] = DriveLetter;
 printf("Enter FileDiskMount \n");
    if (CdImage)
    {
        sprintf(DeviceName, DEVICE_NAME_PREFIX "Cd" "%u", DeviceNumber);
    }
    else
    {
        sprintf(DeviceName, DEVICE_NAME_PREFIX "%u", DeviceNumber);
    }
 printf("FileDiskMount DefineDosDevice VolumeName = %s DeviceName = %s \n", &VolumeName[4], DeviceName);
    if (!DefineDosDevice(
        DDD_RAW_TARGET_PATH,
        &VolumeName[4],
        DeviceName
        ))
    {
        PrintLastError(&VolumeName[4]);
        return -1;
    }
 return 0;
}

运行
C:\Documents and Settings\test>"C:\Documents and Settings\test\桌面\testfilediskexe.exe" /mount 0 c:\1.txt 8M e:
Enter FileDiskMount
FileDiskMount DefineDosDevice VolumeName = e: DeviceName = \Device\FileDisk\File
Disk0

结果还是可以在我的电脑中显示 e: 盘
昨天没有把虚拟的分区显示出来，可能性有2个

1、DefineDosDevice() 的调用有问题
2、FileDisk .sys 在调用了 IoCreateDevice() 之后，还做了其它一些东西，而我没有注意到

于是，决定再次尝试下用  DefineDosDevice() 能不能把虚拟的分区显示出来
.sys 的代码

#include  < ntddk.h >
#include  < ntdddisk.h >
#define  DEVICE_NAME      L"\\DosDevices\\SimpleDriver"
#define  SECTOR_SIZE             512
NTSTATUS DriverEntry(IN PDRIVER_OBJECT DriverObject, IN PUNICODE_STRING RegistryPath);
VOID     DriverUnload(IN PDRIVER_OBJECT DriverObject);
NTSTATUS DeviceControl(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp);
NTSTATUS DeviceCreateClose(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp);
NTSTATUS DeviceReadWrite(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp);
#pragma code_seg( " INIT " )
NTSTATUS DriverEntry(IN PDRIVER_OBJECT DriverObject, IN PUNICODE_STRING RegistryPath)
{   
    NTSTATUS status = STATUS_SUCCESS; 
    UNICODE_STRING uniNameString;
    DEVICE_OBJECT *pCDO = NULL;
    
    KdPrint(("SimpleDriver!DriverEntry \n"));
    
    RtlInitUnicodeString(&uniNameString, DEVICE_NAME);
    status = IoCreateDevice(DriverObject, 0, &uniNameString, FILE_DEVICE_DISK_FILE_SYSTEM, FILE_DEVICE_SECURE_OPEN, FALSE, &pCDO);
    if( !NT_SUCCESS(status) )
     return status; 
    
    DriverObject->DriverUnload = DriverUnload;
    DriverObject->MajorFunction[IRP_MJ_CREATE]         = DeviceCreateClose;
    DriverObject->MajorFunction[IRP_MJ_CLOSE]          = DeviceCreateClose;
    DriverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL] = DeviceControl;
    
    DriverObject->MajorFunction[IRP_MJ_READ]           = DeviceReadWrite;
    DriverObject->MajorFunction[IRP_MJ_WRITE]          = DeviceReadWrite;
    
    return STATUS_SUCCESS;
}
#pragma code_seg( " PAGE " )
VOID DriverUnload(IN PDRIVER_OBJECT DriverObject)
{
    PAGED_CODE();
    
    KdPrint(("SimpleDriver!DriverUnload \n"));
    IoDeleteDevice(DriverObject->DeviceObject);
}
NTSTATUS DeviceCreateClose(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp)
{
    PAGED_CODE();
    KdPrint(("SimpleDriver!DeviceCreateClose \n"));
    Irp->IoStatus.Status = STATUS_SUCCESS;
    Irp->IoStatus.Information = FILE_OPENED;
    IoCompleteRequest(Irp, IO_NO_INCREMENT);
    return STATUS_SUCCESS;
}
NTSTATUS DeviceControl(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp)
{
    NTSTATUS status = STATUS_SUCCESS;
    ULONG nIoCtrlCodes = 0;  // IO控制码
    PIO_STACK_LOCATION IrpStack = NULL;   //IRP堆栈
        
    KdPrint(("SimpleDriver!DeviceControl \n"));
    
    //得到当前调用者的IRP 
    IrpStack = IoGetCurrentIrpStackLocation(Irp);   
    
    nIoCtrlCodes = IrpStack->Parameters.DeviceIoControl.IoControlCode;
    
    KdPrint(("SimpleDriver!DeviceControl IoControlCode = 0x%X\n", nIoCtrlCodes));
    
    switch( IrpStack->Parameters.DeviceIoControl.IoControlCode )
    {
        case IOCTL_DISK_GET_DRIVE_GEOMETRY:
        {          
           PDISK_GEOMETRY  disk_geometry;
            ULONGLONG       length;
           KdPrint(("SimpleDriver!DeviceControl IOCTL_DISK_GET_DRIVE_GEOMETRY \n"));
            if (IrpStack->Parameters.DeviceIoControl.OutputBufferLength < sizeof(DISK_GEOMETRY))
            {
                Irp->IoStatus.Status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }
            disk_geometry = (PDISK_GEOMETRY) Irp->AssociatedIrp.SystemBuffer;
            
            // #define SECTOR_SIZE             512
            disk_geometry->Cylinders.QuadPart = 41940668416 / SECTOR_SIZE / 32 / 2;
            disk_geometry->MediaType = FixedMedia;
            disk_geometry->TracksPerCylinder = 2;
            disk_geometry->SectorsPerTrack = 32;
            disk_geometry->BytesPerSector = SECTOR_SIZE;
            Irp->IoStatus.Information = sizeof(DISK_GEOMETRY);
            Irp->IoStatus.Status = STATUS_SUCCESS;
        }
        break;
        
        case IOCTL_DISK_GET_PARTITION_INFO:
        {
           PPARTITION_INFORMATION  partition_information;
            ULONGLONG               length;
           KdPrint(("SimpleDriver!DeviceControl IOCTL_DISK_GET_PARTITION_INFO \n"));
            if (IrpStack->Parameters.DeviceIoControl.OutputBufferLength < sizeof(PARTITION_INFORMATION))
            {
                Irp->IoStatus.Status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }
            partition_information = (PPARTITION_INFORMATION) Irp->AssociatedIrp.SystemBuffer;
            partition_information->StartingOffset.QuadPart = 0;
            partition_information->PartitionLength.QuadPart = 41940668416;
            partition_information->HiddenSectors = 1;
            partition_information->PartitionNumber = 0;
            partition_information->PartitionType = 0;
            partition_information->BootIndicator = FALSE;
            partition_information->RecognizedPartition = FALSE;
            partition_information->RewritePartition = FALSE;
            Irp->IoStatus.Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(PARTITION_INFORMATION);
        }
        break;
        
        case IOCTL_DISK_IS_WRITABLE:
        {
           KdPrint(("SimpleDriver!DeviceControl IOCTL_DISK_IS_WRITABLE \n"));
           Irp->IoStatus.Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = 0;
            break;
        }
        break;
        
        case IOCTL_DISK_SET_PARTITION_INFO:
        {
           KdPrint(("SimpleDriver!DeviceControl IOCTL_DISK_SET_PARTITION_INFO \n"));
            
            if (IrpStack->Parameters.DeviceIoControl.InputBufferLength < sizeof(SET_PARTITION_INFORMATION))
            {
               Irp->IoStatus.Status = STATUS_INVALID_PARAMETER;
                Irp->IoStatus.Information = 0;
                break;
            }
            
            Irp->IoStatus.Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = 0;
        }
        break;
                
        case IOCTL_DISK_VERIFY:
        {
           PVERIFY_INFORMATION verify_information;
           KdPrint(("SimpleDriver!DeviceControl IOCTL_DISK_VERIFY \n"));
            if (IrpStack->Parameters.DeviceIoControl.InputBufferLength < sizeof(VERIFY_INFORMATION))
            {
                Irp->IoStatus.Status = STATUS_INVALID_PARAMETER;
                Irp->IoStatus.Information = 0;
                break;
            }
            verify_information = (PVERIFY_INFORMATION) Irp->AssociatedIrp.SystemBuffer;
            Irp->IoStatus.Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = verify_information->Length;
        }
        break;
        
        case IOCTL_DISK_CHECK_VERIFY:
        {
           KdPrint(("SimpleDriver!DeviceControl IOCTL_DISK_CHECK_VERIFY \n"));
            Irp->IoStatus.Information = 0;         
            Irp->IoStatus.Status = STATUS_SUCCESS;
        }
        break;     
   
    };
    
    status = Irp->IoStatus.Status; 
    IoCompleteRequest(Irp, IO_NO_INCREMENT); 
    return status; 
}
NTSTATUS DeviceReadWrite(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp)
{
    PIO_STACK_LOCATION  io_stack;
    io_stack = IoGetCurrentIrpStackLocation(Irp);
    if (io_stack->Parameters.Read.Length == 0)
    {
        Irp->IoStatus.Status = STATUS_SUCCESS;
        Irp->IoStatus.Information = 0;
        IoCompleteRequest(Irp, IO_NO_INCREMENT);
        return STATUS_SUCCESS;
    }
    IoMarkIrpPending(Irp);
    return STATUS_PENDING;
}
#pragma code_seg()

.exe 代码

#include  < windows.h >
#include  < winioctl.h >
#include  < stdio.h >
  
void  mount()
{
    if (!DefineDosDevice(DDD_RAW_TARGET_PATH, "e:",
        "\\\\.\\SimpleDriver"
        ))
    {
        printf("DefineDosDevice Error ErrCode = %d", ::GetLastError());
    }
 else
 {
  printf("DefineDosDevice OK ErrCode = %d", ::GetLastError());
 }
}   

int  main( int  argc,  char   * argv[])
{  
 mount();
    return 0;
}

运行结果：
C:\Documents and Settings\test>"C:\Documents and Settings\test\桌面\testDriverTalk.exe"
DefineDosDevice OK ErrCode = 0

但很遗憾！！！！！ e: 盘就是不显示出来

难道跟设备的路径有关系？？？
FileDisk 创建的设备路径是:                 \Device\FileDisk\File
而上述的SimpleDriver 创建的设备路径是  \DosDevices\SimpleDriver

于是尝试将将
.sys 代码中
#define DEVICE_NAME      L"\\DosDevices\\SimpleDriver"
改为:
#define DEVICE_NAME      L"\\Device\\SimpleDriver"

编译……
用 OSRLOADER.exe 加态完驱动后，再用 Winobj.exe 确定了 SimpleDriver 所在的设备路径是 \Device\SimpleDriver

再加 .exe  的
    if (!DefineDosDevice(DDD_RAW_TARGET_PATH, "e:",
        "\\\\.\\SimpleDriver"
        ))

改为
    if (!DefineDosDevice(DDD_RAW_TARGET_PATH, "e:",
        "\\Device\\SimpleDriver"
        ))

编译……，运行
运行结果：
C:\Documents and Settings\test>"C:\Documents and Settings\test\桌面\testDriverTalk.exe"
DefineDosDevice OK ErrCode = 0

恭喜，恭喜！！！！！！！！
在我的电脑中，E: 这个虚拟的分区终于显示出来了

如此证明，昨天 调用 DefineDosDevice() 后，E: 盘没显示出来，跟 设备的路径是有关的
但具体原因未知
设备路径：\DosDevices\SimpleDriver   调用 DefineDosDevice() 后， 不显示 E: 盘
设备路径：\Device\SimpleDriver         调用 DefineDosDevice() 后， 显示 E: 盘

双击 E: 盘
提示错误信息： “无法访问 E:\ 函数不正确。”
具体原因不详， 有可能是 .sys 没有处理相关 IRP 的原因，需要进一步研究

接下来，想试一下，直接在加载驱动的时候，调用 IoCreateSymbolicLink

修改 .sys 代码为

#include  < ntddk.h >
#include  < ntdddisk.h >
#define  DEVICE_NAME      L"\\Device\\SimpleDriver"
#define  DEVICE_LINK_NAME L"\\\\.\\e"
#define  SECTOR_SIZE             512

NTSTATUS DriverEntry(IN PDRIVER_OBJECT DriverObject, IN PUNICODE_STRING RegistryPath);
VOID     DriverUnload(IN PDRIVER_OBJECT DriverObject);
NTSTATUS DeviceControl(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp);
NTSTATUS DeviceCreateClose(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp);
NTSTATUS DeviceReadWrite(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp);
#pragma code_seg( " INIT " )
NTSTATUS DriverEntry(IN PDRIVER_OBJECT DriverObject, IN PUNICODE_STRING RegistryPath)
{   
    NTSTATUS status = STATUS_SUCCESS; 
    UNICODE_STRING uniNameString;
    UNICODE_STRING uniLinkString;
    DEVICE_OBJECT *pCDO = NULL;
    
    KdPrint(("SimpleDriver!DriverEntry \n"));
    
    RtlInitUnicodeString(&uniNameString, DEVICE_NAME);
    status = IoCreateDevice(DriverObject, 0, &uniNameString, FILE_DEVICE_DISK_FILE_SYSTEM, FILE_DEVICE_SECURE_OPEN, FALSE, &pCDO);
    if( !NT_SUCCESS(status) )
     return status; 
    
    RtlInitUnicodeString(&uniLinkString, DEVICE_LINK_NAME);
    status = IoCreateSymbolicLink(&uniLinkString, &uniNameString);
    if(!NT_SUCCESS(status))
     return status;                                          
    DriverObject->DriverUnload = DriverUnload;
    DriverObject->MajorFunction[IRP_MJ_CREATE]         = DeviceCreateClose;
    DriverObject->MajorFunction[IRP_MJ_CLOSE]          = DeviceCreateClose;
    DriverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL] = DeviceControl;
    
    DriverObject->MajorFunction[IRP_MJ_READ]           = DeviceReadWrite;
    DriverObject->MajorFunction[IRP_MJ_WRITE]          = DeviceReadWrite;
    
    return STATUS_SUCCESS;
}
#pragma code_seg( " PAGE " )
VOID DriverUnload(IN PDRIVER_OBJECT DriverObject)
{
    UNICODE_STRING uniNameString;
    PAGED_CODE();
    
    KdPrint(("SimpleDriver!DriverUnload \n"));
    RtlInitUnicodeString(&uniNameString, DEVICE_LINK_NAME);
    IoDeleteSymbolicLink(&uniNameString);
    IoDeleteDevice(DriverObject->DeviceObject);
}
NTSTATUS DeviceCreateClose(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp)
{
    PAGED_CODE();
    KdPrint(("SimpleDriver!DeviceCreateClose \n"));
    Irp->IoStatus.Status = STATUS_SUCCESS;
    Irp->IoStatus.Information = FILE_OPENED;
    IoCompleteRequest(Irp, IO_NO_INCREMENT);
    return STATUS_SUCCESS;
}
NTSTATUS DeviceControl(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp)
{
    NTSTATUS status = STATUS_SUCCESS;
    ULONG nIoCtrlCodes = 0;  // IO控制码
    PIO_STACK_LOCATION IrpStack = NULL;   //IRP堆栈
        
    KdPrint(("SimpleDriver!DeviceControl \n"));
    
    //得到当前调用者的IRP 
    IrpStack = IoGetCurrentIrpStackLocation(Irp);   
    
    nIoCtrlCodes = IrpStack->Parameters.DeviceIoControl.IoControlCode;
    
    KdPrint(("SimpleDriver!DeviceControl IoControlCode = 0x%X\n", nIoCtrlCodes));
    
    switch( IrpStack->Parameters.DeviceIoControl.IoControlCode )
    {
        case IOCTL_DISK_GET_DRIVE_GEOMETRY:
        {
           PDISK_GEOMETRY  disk_geometry;
            ULONGLONG       length;
            if (IrpStack->Parameters.DeviceIoControl.OutputBufferLength < sizeof(DISK_GEOMETRY))
            {
                Irp->IoStatus.Status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }
            disk_geometry = (PDISK_GEOMETRY) Irp->AssociatedIrp.SystemBuffer;
            
            // #define SECTOR_SIZE             512
            disk_geometry->Cylinders.QuadPart = 41940668416 / SECTOR_SIZE / 32 / 2;
            disk_geometry->MediaType = FixedMedia;
            disk_geometry->TracksPerCylinder = 2;
            disk_geometry->SectorsPerTrack = 32;
            disk_geometry->BytesPerSector = SECTOR_SIZE;
            Irp->IoStatus.Information = sizeof(DISK_GEOMETRY);
            Irp->IoStatus.Status = STATUS_SUCCESS;
        }
        break;
        
        case IOCTL_DISK_GET_PARTITION_INFO:
        {
           PPARTITION_INFORMATION  partition_information;
            ULONGLONG               length;
            if (IrpStack->Parameters.DeviceIoControl.OutputBufferLength < sizeof(PARTITION_INFORMATION))
            {
                Irp->IoStatus.Status = STATUS_BUFFER_TOO_SMALL;
                Irp->IoStatus.Information = 0;
                break;
            }
            partition_information = (PPARTITION_INFORMATION) Irp->AssociatedIrp.SystemBuffer;
            partition_information->StartingOffset.QuadPart = 0;
            partition_information->PartitionLength.QuadPart = 41940668416;
            partition_information->HiddenSectors = 1;
            partition_information->PartitionNumber = 0;
            partition_information->PartitionType = 0;
            partition_information->BootIndicator = FALSE;
            partition_information->RecognizedPartition = FALSE;
            partition_information->RewritePartition = FALSE;
            Irp->IoStatus.Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(PARTITION_INFORMATION);
        }
        break;
        
        case IOCTL_DISK_IS_WRITABLE:
        {
           Irp->IoStatus.Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = 0;
            break;
        }
        break;
        
        case IOCTL_DISK_SET_PARTITION_INFO:
        {
            if (IrpStack->Parameters.DeviceIoControl.InputBufferLength < sizeof(SET_PARTITION_INFORMATION))
            {
               Irp->IoStatus.Status = STATUS_INVALID_PARAMETER;
                Irp->IoStatus.Information = 0;
                break;
            }
            
            Irp->IoStatus.Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = 0;
        }
        break;
                
        case IOCTL_DISK_VERIFY:
        {
           PVERIFY_INFORMATION verify_information;
            if (IrpStack->Parameters.DeviceIoControl.InputBufferLength < sizeof(VERIFY_INFORMATION))
            {
                Irp->IoStatus.Status = STATUS_INVALID_PARAMETER;
                Irp->IoStatus.Information = 0;
                break;
            }
            verify_information = (PVERIFY_INFORMATION) Irp->AssociatedIrp.SystemBuffer;
            Irp->IoStatus.Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = verify_information->Length;
        }
        break;
        
        case IOCTL_DISK_CHECK_VERIFY:
        {
            Irp->IoStatus.Information = 0;         
            Irp->IoStatus.Status = STATUS_SUCCESS;
        }
        break;        
    };
    
    status = Irp->IoStatus.Status; 
    IoCompleteRequest(Irp, IO_NO_INCREMENT); 
    return status; 
}
NTSTATUS DeviceReadWrite(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp)
{
    PIO_STACK_LOCATION  io_stack;
    io_stack = IoGetCurrentIrpStackLocation(Irp);
    if (io_stack->Parameters.Read.Length == 0)
    {
        Irp->IoStatus.Status = STATUS_SUCCESS;
        Irp->IoStatus.Information = 0;
        IoCompleteRequest(Irp, IO_NO_INCREMENT);
        return STATUS_SUCCESS;
    }
    IoMarkIrpPending(Irp);
    return STATUS_PENDING;
}
#pragma code_seg()

使用 OSRLOADER.exe 加载 .sys 时，提示错误信息 “文件名、目录名或卷标语法不正确”，
应该是 #define DEVICE_LINK_NAME L"\\\\.\\e" 这个非法了

尝试修改为
#define DEVICE_LINK_NAME L"\\.\\e"
加载时提示错误信息“系统找不到指定的路径”，晕，这好像是应用层调用的路径，

再尝试修改为
#define DEVICE_NAME      L"\\Device\\SimpleDriver"
#define DEVICE_LINK_NAME L"\\DosDevices\\x:"

加载成功
用 Winobj.exe 查看

设备目录有 \Device\SimpleDriver
也有 \GLOBAL??\X:

但在我的电脑中并没有显示 x: 出来
奇怪的地方是 用  DefineDosDevice() 函数不会在 \GLOBAL??\  下面生成分区的别名，但它又怎么访问得到呢？
而 使用 IoCreateSymbolicLink() 可以在 \GLOBAL??\ 下生成别名，但在我的电脑中却又不会显示

DefineDosDevice() 函数的作用不是相当于  IoCreateSymbolicLink()?
-- 未解决


本集终于可以实现虚拟出一个分区的功能了，但还有很多细节问题需要深入再研究，查找相关资料
问题
1、
设备路径：\DosDevices\SimpleDriver   调用 DefineDosDevice() 后， 不显示 E: 盘
设备路径：\Device\SimpleDriver         调用 DefineDosDevice() 后， 显示 E: 盘

原因是： 未解决

2、用  DefineDosDevice() 函数不会在 \GLOBAL??\  下面生成分区的别名，但它又怎么访问得到呢？
而 使用 IoCreateSymbolicLink() 可以在 \GLOBAL??\ 下生成别名，但在我的电脑中却又不会显示

DefineDosDevice() 函数的作用不是相当于  IoCreateSymbolicLink()?
-- 未解决

--- 6集 完 ---