我成功地從C＃調用了advapi32的LsaEnumerateAccountRights（）。 現在我如何解組它返回的LSA_UNICODE_STRING數組呢？

Question

它是指向LSA_UNICODE_STRING結構數組的指針。 我找到了一些反向的代碼，即從C＃字符串創建一個LSA_UNICODE_STRING 。 您可以在下面的幫助程序代碼部分中看到。

我所做的，包括對LsaEnumerateAccountRights()的調用似乎工作正常。 為數組指針和計數返回合理的值。

我手足無措，如何在那些狠命琴弦。 請幫助？ 好嗎？

更新： nobugz的助手函數在下面的答案中是ALMOST正確的，你只需UnicodeEncoding.CharSize來划分長度。 多虧了他，我現在可以看到數組中的FIRST字符串了。 請參閱下面兩個代碼部分末尾的更新。

現在，我如何做地獄世界的指針運算？

更新2.5：查看功能代碼的答案。 我丟失了舊的“錯誤”代碼。

Answer 1

找到了！ 在這篇博文中 。 現在修改后的代碼完全有效。 它甚至是64位安全的！

主要代碼：

IntPtr sid = IntPtr.Zero;
int sidSize = 0;
StringBuilder domainName = new StringBuilder();
int nameSize = 0;
int accountType = 0;

LookupAccountName("\\\\" + tbHost.Text, tbUsername.Text, sid, ref sidSize,
    domainName, ref nameSize, ref accountType);
domainName = new StringBuilder(nameSize);
sid = Marshal.AllocHGlobal(sidSize);

bool result = LookupAccountName("\\\\" + tbHost.Text, tbUsername.Text, sid, ref sidSize,
    domainName, ref nameSize, ref accountType);

myResults.Text += String.Format("LookupAccountName(): Result {0}, SID {1}\n", result, sid);

LSA_UNICODE_STRING systemName = string2LSAUS("\\\\" + tbHost.Text);
IntPtr policyHandle = IntPtr.Zero;
LSA_OBJECT_ATTRIBUTES objAttrs = new LSA_OBJECT_ATTRIBUTES();
uint retVal = LsaOpenPolicy(ref systemName, ref objAttrs,
                    POLICY_LOOKUP_NAMES | POLICY_VIEW_LOCAL_INFORMATION, out policyHandle);

myResults.Text += String.Format("LsaOpenPolicy(): Result {0}, Policy Handle {1}\n", retVal, policyHandle);

IntPtr rightsArray = IntPtr.Zero;
ulong rightsCount = 0;
long lretVal = LsaEnumerateAccountRights(policyHandle, sid, out rightsArray, out rightsCount);
retVal = LsaNtStatusToWinError(lretVal);

if (retVal != 0)
    throw new System.ComponentModel.Win32Exception((int)retVal);

myResults.Text += String.Format("LsaEnumerateAccountRights(): Result {0}, RightsArray {1}, Count {2}\n",
    retVal, rightsArray, rightsCount);

LSA_UNICODE_STRING myLsaus = new LSA_UNICODE_STRING();
for (ulong i = 0; i < rightsCount; i++)
{
    IntPtr itemAddr = new IntPtr(rightsArray.ToInt64() + (long)(i * (ulong) Marshal.SizeOf(myLsaus)));
    myLsaus = (WinNetUtils.LSA_UNICODE_STRING)Marshal.PtrToStructure(itemAddr, myLsaus.GetType());
    string thisRight = WinNetUtils.LSAUS2string(myLsaus);
    NonBlockingPrint(wmiResults, "Right #{0}: {1}\n", i+1, thisRight);
}
LsaClose(policyHandle);

輔助函數，導入等：

public const int POLICY_VIEW_LOCAL_INFORMATION = 0x1;
public const int POLICY_LOOKUP_NAMES = 0x00000800;

[DllImport("advapi32.dll", CharSet = CharSet.Unicode, PreserveSig = true)]
public static extern UInt32 LsaNtStatusToWinError(
    long Status);

[DllImport("advapi32.dll", CharSet = CharSet.Unicode, SetLastError = true, PreserveSig = true)]
public static extern bool ConvertStringSidToSid(
    string StringSid, out IntPtr pSid);

[DllImport("advapi32.dll", CharSet = CharSet.Unicode, SetLastError = true, PreserveSig = true)]
public static extern bool LookupAccountName( 
    string lpSystemName, string lpAccountName, 
    IntPtr psid, ref int cbsid, 
    StringBuilder domainName, ref int cbdomainLength, 
    ref int use );

[DllImport("advapi32.dll", CharSet = CharSet.Unicode, PreserveSig = true)]
public static extern UInt32 LsaOpenPolicy(
    ref LSA_UNICODE_STRING SystemName,
    ref LSA_OBJECT_ATTRIBUTES ObjectAttributes,
    Int32 DesiredAccess,
    out IntPtr PolicyHandle );

[DllImport("advapi32.dll", SetLastError = true, PreserveSig = true)]
public static extern long LsaEnumerateAccountRights(
    IntPtr PolicyHandle, IntPtr AccountSid,
    out /* LSA_UNICODE_STRING[] */ IntPtr UserRights,
    out ulong CountOfRights); 

[DllImport("advapi32.dll", SetLastError = true, PreserveSig = true)]
public static extern long LsaClose(
            IntPtr PolicyHandle);

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct LSA_UNICODE_STRING 
{ 
  public UInt16 Length; 
  public UInt16 MaximumLength; 
  public IntPtr Buffer; 
}

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct LSA_OBJECT_ATTRIBUTES
{
    public IntPtr RootDirectory;
    public IntPtr SecurityDescriptor;
    public IntPtr SecurityQualityOfService;
    public LSA_UNICODE_STRING ObjectName;
    public UInt32 Attributes;
    public UInt32 Length;
}

public static LSA_UNICODE_STRING string2LSAUS(string myString)
{
    LSA_UNICODE_STRING retStr = new LSA_UNICODE_STRING();
    retStr.Buffer = Marshal.StringToHGlobalUni(myString);
    retStr.Length = (UInt16)(myString.Length * UnicodeEncoding.CharSize);
    retStr.MaximumLength = (UInt16)((myString.Length + 1) * UnicodeEncoding.CharSize);
    return retStr;
}

public static string LSAUS2string(LSA_UNICODE_STRING lsaus)
{
    char[] cvt = new char[lsaus.Length / UnicodeEncoding.CharSize];
    Marshal.Copy(lsaus.Buffer, cvt, 0, lsaus.Length / UnicodeEncoding.CharSize);
    return new string(cvt);
}

Answer 2

這應該對你有用：

    private static string LSAUS2String(LSA_UNICODE_STRING lsa) {
        char[] cvt = new char[lsa.Length];
        Marshal.Copy(lsa.Buffer, cvt, 0, lsa.Length);
        return new string(cvt);
    }