检测何时创建新的虚拟驱动器

Posted 2023-03-17

【中文标题】检测何时创建新的虚拟驱动器

【英文标题】：Detect when a new virtual drive is created

【发布时间】：2013-07-28 14:09:10

【问题描述】：

我如何知道计算机上安装了哪些trueCrypt 卷？

注意我已经知道可以挂载哪些文件了。换句话说，唯一可以挂载的卷是：C:\Vol1.tc、C:\Vol2.tc 和C:\Vol3.tc。

我如何知道卷何时被卸载？

我设法通过使用 .net 类 FileSystemWatcher 来做到这一点。每一个 当我卸载卷时，我注意到该事件 FileSystemWatcher.Changed 着火了。

我如何知道何时安装了卷？

这就是我遇到麻烦的地方！ 我是否经常查询驱动器并查看驱动器是否存在。 这听起来是个坏主意，因为如果有人插入 USB 并且 windows 将驱动器号分配给它我会出错。 我如何知道何时创建了新的虚拟驱动器？

为什么我需要这个？

我需要创建一个用户可以看到什么的应用程序 trueCrypt 卷是从他的手机安装的。唯一的我 缺少要做的是找出何时安装卷......

【问题讨论】：

Windows 在添加或删除卷时发送 WM_DEVICECHANGE 广播消息。您需要在代码中处理此 windows 消息。

【参考方案1】：

正如 Eugene Mayevski 'EldoS Corp 所说，您应该使用 WM_DEVICECHANGE 事件。

结合我给你on this question的答案，这里是一个示例代码：

class Program : System.Windows.Forms.Form

    static void Main(string[] args)
    
        System.Windows.Forms.Application.Run(new Program());
    

    const int WM_DEVICECHANGE = 0x0219;
    const int NB_MOUNTED_VOLUMES = 26;
    protected override void WndProc(ref System.Windows.Forms.Message m)
    
        switch (m.Msg)
        
            case WM_DEVICECHANGE:
                ShowChange();
                break;
        
        base.WndProc(ref m);
    

    private String[] m_oldMount;
    public Program()
    
        m_oldMount = new String[NB_MOUNTED_VOLUMES];
        for (int i = 0; i < NB_MOUNTED_VOLUMES; i++)
            m_oldMount[i] = String.Empty;
    

    private void ShowChange()
    
        String[] currentMount = GetMountList();
        for (int i = 0; i < NB_MOUNTED_VOLUMES; i++)
        
            if (currentMount[i] != m_oldMount[i])
            
                if (String.IsNullOrEmpty(currentMount[i]))
                
                    Console.WriteLine("0 : Dismount on 1: => 2",
                        DateTime.Now,
                        (char)('A' + i),
                        m_oldMount[i]);
                
                else
                
                    Console.WriteLine("0 : Mount on 1: => 2",
                        DateTime.Now,
                        (char)('A' + i),
                        currentMount[i]);
                
            
        
        m_oldMount = currentMount;
    
    private String[] GetMountList()
    
        uint size = (uint)Marshal.SizeOf(typeof(MOUNT_LIST_STRUCT));
        IntPtr buffer = Marshal.AllocHGlobal((int)size);
        uint bytesReturned;
        IntPtr _hdev = CreateFile("\\\\.\\TrueCrypt", FileAccess.ReadWrite, FileShare.ReadWrite, IntPtr.Zero, FileMode.Open, 0, IntPtr.Zero);
        bool bResult = DeviceIoControl(_hdev, TC_IOCTL_GET_MOUNTED_VOLUMES, buffer, size, buffer, size, out bytesReturned, IntPtr.Zero);
        MOUNT_LIST_STRUCT mount = new MOUNT_LIST_STRUCT();
        Marshal.PtrToStructure(buffer, mount);
        Marshal.FreeHGlobal(buffer);

        return mount.wszVolume.Select(m => m.ToString()).ToArray();
    

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Pack = 1)]
    class MOUNT_LIST_STRUCT
    
        public readonly UInt32 ulMountedDrives; /* Bitfield of all mounted drive letters */
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 26)]
        public readonly MOUNT_LIST_STRUCT_VOLUME_NAME[] wszVolume;  /* Volume names of mounted volumes */
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 26)]
        public readonly UInt64[] diskLength;
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 26)]
        public readonly int[] ea;
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 26)]
        public readonly int[] volumeType;   /* Volume type (e.g. PROP_VOL_TYPE_OUTER, PROP_VOL_TYPE_OUTER_VOL_WRITE_PREVENTED, etc.) */
    

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Pack = 1)]
    struct MOUNT_LIST_STRUCT_VOLUME_NAME
    
        [MarshalAs(UnmanagedType.ByValArray, ArraySubType = UnmanagedType.I2, SizeConst = 260)]
        public readonly char[] wszVolume;   /* Volume names of mounted volumes */

        public override string ToString()
        
            return (new String(wszVolume)).TrimEnd('\0');
        
    

    public static int CTL_CODE(int DeviceType, int Function, int Method, int Access)
    
        return (((DeviceType) << 16) | ((Access) << 14) | ((Function) << 2)
          | (Method));
    
    private static readonly uint TC_IOCTL_GET_MOUNTED_VOLUMES = (uint)CTL_CODE(0x00000022, 0x800 + (6), 0, 0);

    [DllImport("kernel32.dll", ExactSpelling = true, SetLastError = true, CharSet = CharSet.Auto)]
    static extern bool DeviceIoControl(IntPtr hDevice, uint dwIoControlCode,
    IntPtr lpInBuffer, uint nInBufferSize,
    IntPtr lpOutBuffer, uint nOutBufferSize,
    out uint lpBytesReturned, IntPtr lpOverlapped);

    [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public static extern IntPtr CreateFile(
         [MarshalAs(UnmanagedType.LPTStr)] string filename,
         [MarshalAs(UnmanagedType.U4)] FileAccess access,
         [MarshalAs(UnmanagedType.U4)] FileShare share,
         IntPtr securityAttributes, // optional SECURITY_ATTRIBUTES struct or IntPtr.Zero
         [MarshalAs(UnmanagedType.U4)] FileMode creationDisposition,
         [MarshalAs(UnmanagedType.U4)] FileAttributes flagsAndAttributes,
         IntPtr templateFile);