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Open directory with CreateFile

I am trying to use the CreateFile function to access directory information. However, I get a win32 error code of 5, which means denied access. Please inform.

CreateFile(path, GENERIC_READ, FILE_SHARE_READ, IntPtr.Zero, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, IntPtr.Zero);

This is a call, and as indicated in the documentation, FILE_FLAG_BACKUP_SEMANTICS is used. Importing the DLL seems to work fine and looks like this:

[DllImport("kernel32.dll", SetLastError = true)]
public static extern IntPtr CreateFile(string filename,
                                    uint desiredAccess,
                                    uint sharedMode,
                                    IntPtr securityAttributes,
                                    uint creationDisposition,
                                    uint flagsAndAttributes,
                                    IntPtr templateFile);

Update: I need to get a directory descriptor so that I can use GetFileInformationByHandle () and retrieve a unique identifier. This method currently works with files; it does not work with directories at present.

: X : , - , . , ..NET - , , win32

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, , , . SE_BACKUP_NAME , AdjustTokenPrivileges API. FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE sharedMode. CreateFile, GetFileInformationByHandle BY_HANDLE_FILE_INFORMATION.

. ,

#include <windows.h>
#include <tchar.h>

int _tmain()
{
    HANDLE hAccessToken = NULL;
    HANDLE hFile = INVALID_HANDLE_VALUE;

    __try {
        LUID luidPrivilege;
        DWORD dwErrorCode;
        BY_HANDLE_FILE_INFORMATION fiFileInfo;

        // -----------------------------------------------------
        // first of all we need anable SE_BACKUP_NAME privilege
        // -----------------------------------------------------
        if (!OpenProcessToken (GetCurrentProcess(),
                               TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY,
                               &hAccessToken))
            __leave;

        if (LookupPrivilegeValue (NULL, SE_BACKUP_NAME, &luidPrivilege)) {
            TOKEN_PRIVILEGES tpPrivileges;
            tpPrivileges.PrivilegeCount = 1;
            tpPrivileges.Privileges[0].Luid = luidPrivilege;
            tpPrivileges.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
            AdjustTokenPrivileges (hAccessToken, FALSE, &tpPrivileges, 
                                   0, NULL, NULL);
            if ((dwErrorCode = GetLastError ()) != ERROR_SUCCESS)
                __leave;
        }
        else
            __leave;

        // -----------------------------------------------------
        // now one can open directory and get 
        // -----------------------------------------------------
        hFile = CreateFile (TEXT("C:\\"),
                            0, //GENERIC_READ, 
                            0, //FILE_SHARE_READ, //FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
                            NULL,
                            OPEN_EXISTING, 
                            FILE_FLAG_BACKUP_SEMANTICS,
                            NULL);
        if (hFile == INVALID_HANDLE_VALUE)
            __leave;
        if (!GetFileInformationByHandle (hFile, &fiFileInfo))
            __leave;

        _tprintf(TEXT("VolumeSerialNumber: 0x%08X\n"), fiFileInfo.dwVolumeSerialNumber);
        _tprintf(TEXT("FileIndex: 0x%08X%08X\n"), fiFileInfo.nFileIndexHigh, fiFileInfo.nFileIndexLow);
    }
    __finally {
        if (hFile != INVALID_HANDLE_VALUE)
            CloseHandle (hFile);
        if (hAccessToken != NULL)
            CloseHandle (hAccessToken);
    }

    return 0;
}

C:\ , NTFS. , (. __leave). , requireAdministrator " UAC" (. " " ). . #.

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