C# P/Invoke Win32 函数 RegQueryInfoKey

Question

我正在尝试移植以下 C++ 代码：

BOOL SyskeyGetClassBytes(HKEY hKeyReg,LPSTR keyName,LPSTR valueName,LPBYTE classBytes) {
HKEY hKey,hSubKey;
DWORD dwDisposition=0,classSize;
BYTE classStr[16];
LONG ret;
BOOL isSuccess = FALSE;

ret = RegCreateKeyEx(hKeyReg,keyName,0,NULL,REG_OPTION_NON_VOLATILE,KEY_QUERY_VALUE,NULL,&hKey,&dwDisposition);

if(ret!=ERROR_SUCCESS) 
    return FALSE;
else if(dwDisposition!=REG_OPENED_EXISTING_KEY) {
    RegCloseKey(hKey);
    return FALSE;
}
else {
    if(RegOpenKeyEx(hKey,valueName,0,KEY_READ,&hSubKey)==ERROR_SUCCESS) {
        classSize = 8+1;
        ret = RegQueryInfoKey(hSubKey,(LPTSTR)classStr,&classSize,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);
        if((ret==ERROR_SUCCESS)&&(classSize==8)) {
            classBytes[0]= (HexDigitToByte(classStr[0]) << 4) | HexDigitToByte(classStr[1]);
            classBytes[1]= (HexDigitToByte(classStr[2]) << 4) | HexDigitToByte(classStr[3]);
            classBytes[2]= (HexDigitToByte(classStr[4]) << 4) | HexDigitToByte(classStr[5]);
            classBytes[3]= (HexDigitToByte(classStr[6]) << 4) | HexDigitToByte(classStr[7]);
            isSuccess = TRUE;
        }
        RegCloseKey(hSubKey);
    }
    RegCloseKey(hKey);
}

return isSuccess;

}

我花了大约 5 个小时试图找出我的问题，但没有成功。我知道我正确地调用了这个方法。我的 C# 代码是

 unsafe static bool SyskeyGetClassBytes(RegistryHive hKeyReg, string keyName, string valueName, byte* classBytes)
    {
        UIntPtr hSubKey;
        UIntPtr hKey;
        RegResult tmp; ;
        uint classSize;
        StringBuilder classStr = new StringBuilder();
        int ret;
        bool isSuccess = false;
        ret = RegCreateKeyEx(hKeyReg, keyName, 0, null, RegOption.NonVolatile, RegSAM.QueryValue, UIntPtr.Zero, out hKey, out tmp);

        if (ret != 0)
        {
            return false;

        }
        else if (tmp != RegResult.OpenedExistingKey)
        {
            return false;
        }
        else
        {
            int res = RegOpenKeyEx(hKey, valueName, 0, (int)RegSAM.Read, out hSubKey);
            if (res == 0)
            {
                classSize = 8 + 1;
                ret = RegQueryInfoKey(hSubKey, out classStr, ref classSize, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero);

                if ((classSize == 8))
                {
                    classBytes[0] = (byte)((byte)(HexDigitToByte(classStr[0]) << (byte)4) | HexDigitToByte(classStr[1]));
                    classBytes[1] = (byte)((byte)(HexDigitToByte(classStr[2]) << (byte)4) | HexDigitToByte(classStr[3]));
                    classBytes[2] = (byte)((byte)(HexDigitToByte(classStr[4]) << (byte)4) | HexDigitToByte(classStr[5]));
                    classBytes[3] = (byte)((byte)(HexDigitToByte(classStr[6]) << (byte)4) | HexDigitToByte(classStr[7]));
                    isSuccess = true;
                }
                RegCloseKey(hSubKey);
            }
            else
            {
                return false;
            }
            RegCloseKey(hKey);
        }
        return isSuccess;
    }

调试对我来说有点困难，但最终我确定问题出在这一行。执行似乎随后停止。

 ret = RegQueryInfoKey(hSubKey, out classStr, ref classSize, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero);

我知道这不是权限问题，因为这个 C# 程序使用管理员权限和本地系统帐户运行。我需要.Net API 不提供的方法是RegQueryInfoKey。我使用的 P/Invoke 签名和类型是：

  [StructLayout(LayoutKind.Sequential)]
    public struct SECURITY_ATTRIBUTES
    {
        public int nLength;
        public unsafe byte* lpSecurityDescriptor;
        public int bInheritHandle;
    }
    [Flags]
    public enum RegOption
    {
        NonVolatile = 0x0,
        Volatile = 0x1,
        CreateLink = 0x2,
        BackupRestore = 0x4,
        OpenLink = 0x8
    }

    [Flags]
    public enum RegSAM
    {
        QueryValue = 0x0001,
        SetValue = 0x0002,
        CreateSubKey = 0x0004,
        EnumerateSubKeys = 0x0008,
        Notify = 0x0010,
        CreateLink = 0x0020,
        WOW64_32Key = 0x0200,
        WOW64_64Key = 0x0100,
        WOW64_Res = 0x0300,
        Read = 0x00020019,
        Write = 0x00020006,
        Execute = 0x00020019,
        AllAccess = 0x000f003f
    }

    public enum RegResult
    {
        CreatedNewKey = 0x00000001,
        OpenedExistingKey = 0x00000002
    }
    [DllImport("advapi32.dll", CharSet = CharSet.Auto)]
    public static extern int RegOpenKeyEx(
      UIntPtr hKey,
      string subKey,
      int ulOptions,
      int samDesired,
      out UIntPtr hkResult);
    [DllImport("advapi32.dll", SetLastError = true)]
    public static extern int RegCloseKey(
        UIntPtr hKey);
    [DllImport("advapi32.dll", SetLastError = true)]
    static extern int RegCreateKeyEx(
                RegistryHive hKey,
                string lpSubKey,
                int Reserved,
                string lpClass,
                RegOption dwOptions,
                RegSAM samDesired,
                UIntPtr lpSecurityAttributes,
                out UIntPtr phkResult,
                out RegResult lpdwDisposition);
    [DllImport("advapi32.dll", EntryPoint = "RegQueryInfoKey", CallingConvention = CallingConvention.Winapi, SetLastError = true)]
    extern private static int RegQueryInfoKey(
        UIntPtr hkey,
        out StringBuilder lpClass,
        ref uint lpcbClass,
        IntPtr lpReserved,
        IntPtr lpcSubKeys,
        IntPtr lpcbMaxSubKeyLen,
        IntPtr lpcbMaxClassLen,
        IntPtr lpcValues,
        IntPtr lpcbMaxValueNameLen,
        IntPtr lpcbMaxValueLen,
        IntPtr lpcbSecurityDescriptor,
        IntPtr lpftLastWriteTime);

Answer 1

试试这个签名 RegQueryInfoKey:

[DllImport("advapi32.dll", EntryPoint="RegQueryInfoKey", CallingConvention=CallingConvention.Winapi, SetLastError=true)]
 extern private static int RegQueryInfoKey(
 UIntPtr hkey,
 out StringBuilder lpClass,
 ref uint lpcbClass,
 IntPtr lpReserved,
 out uint lpcSubKeys,
 out uint lpcbMaxSubKeyLen,
 out uint lpcbMaxClassLen,
 out uint lpcValues,
 out uint lpcbMaxValueNameLen,
 out uint lpcbMaxValueLen,
 out uint lpcbSecurityDescriptor,
 IntPtr lpftLastWriteTime);

您没有将它们声明为输出参数，并且在RegQueryInfoKey Win32 调用中它们是_Out_opt_。

Answer 2

您需要初始化您的StringBuilder，使其具有足够的容量来存储classSize 个字符。

classSize = 8 + 1;
classStr.Capacity = classSize;
ret = RegQueryInfoKey(hSubKey, out classStr, ref classSize, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero);

编组器将使用StringBuilder 上设置的容量将容量大小的缓冲区发送到RegQueryInfoKey 函数。没有它，您可能会损坏内存。

见http://msdn.microsoft.com/en-us/library/s9ts558h.aspx#cpcondefaultmarshalingforstringsanchor3

Answer 3

lpClass 参数声明不正确。按值传递StringBuilder。

[DllImport("advapi32.dll")]
extern private static int RegQueryInfoKey(
    UIntPtr hkey,
    StringBuilder lpClass,
    ref uint lpcbClass,
    IntPtr lpReserved,
    IntPtr lpcSubKeys,
    IntPtr lpcbMaxSubKeyLen,
    IntPtr lpcbMaxClassLen,
    IntPtr lpcValues,
    IntPtr lpcbMaxValueNameLen,
    IntPtr lpcbMaxValueLen,
    IntPtr lpcbSecurityDescriptor,
    IntPtr lpftLastWriteTime
);

您还需要分配StringBuilder 实例以获得所需的容量。所以，像这样分配StringBuilder：

StringBuilder classStr = new StringBuilder(255);//or whatever length you like

然后像这样设置classSize：

classSize = classStr.Capacity+1;

我删除了DllImport的参数。大部分都不需要，SetLastError 不正确。

您的代码可能存在其他问题，但通过这些更改，至少对 RegQueryInfoKey 的调用将匹配您的 C++ 代码。