It's a pointer to an array of LSA_UNICODE_STRING
structures. I found some code that does the inverse, i.e., create a LSA_UNICODE_STRING
from a C# string. You can see that in the helper code section below.
What I have up to and including the call to LsaEnumerateAccountRights()
seems to work just fine. Sensible values are returned for the array pointer and for the count.
I am at a loss as to how to get at those blasted strings. Help please? Pretty please?
UPDATE: nobugz's helper function in his answer below is ALMOST right, you only have to divide the length by UnicodeEncoding.CharSize
. Thanks to him, I can now see the FIRST string in the array. See the updates at the end of both code sections below.
Now, how the netherworld do I do pointer arithmetic?
UPDATE 2: Found it! In this blog post. Now the amended code below works fully. It's even 64-bit safe!
The main code:
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);
}
The helper functions, imports etc:
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);
[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);
}