c#-GetTokenInformation返回的TOKEN_PRIVILEGES.LUID_AND_ATTRIBUTES数组的设置大小

我正在尝试检索特权和它们与C#中的令牌相关联的当前状态,但我不知道如何调整返回的LUID_AND_ATTRIBUTES数组的大小以适合元素的实际数量.

从MSDN

When MarshalAsAttribute.Value is set to ByValArray, the SizeConst must be set to indicate the number of elements in the array.

在调用GetTokenInformation之后,我能够查看TOKEN_PRIVILEGES.PrivilegeCount属性,并看到我正在使用的令牌具有Privilege Constants参考页面上列出的35个特权中的24个.更改SizeConst = 24将使我能够看到所有这些,而不仅仅是第一个
(根据PInvoke的用法示例,我最初设置SizeConst = 1)

有没有一种方法可以在创建传入数组时指定传入数组的深度,或者在编写代码之前我是否需要知道将要拥有多少特权？

代码段

[DllImport("advapi32.dll", SetLastError = true)]
protected static extern bool GetTokenInformation(IntPtr TokenHandle, TOKEN_INFORMATION_CLASS TokenInformationClass, IntPtr TokenInformation, int TokenInformationLength, ref int ReturnLength);

[DllImport("advapi32.dll", SetLastError = true, CharSet = CharSet.Auto)][return: MarshalAs(UnmanagedType.Bool)]
protected static extern bool LookupPrivilegeName(string lpSystemName, IntPtr lpLuid,System.Text.StringBuilder lpName, ref int cchName);

protected struct TOKEN_PRIVILEGES {
  public UInt32 PrivilegeCount;
  [MarshalAs(UnmanagedType.ByValArray, SizeConst = 1)]
  public LUID_AND_ATTRIBUTES[] Privileges;
}//TOKEN_PRIVILEGES

[StructLayout(LayoutKind.Sequential)]
protected struct LUID_AND_ATTRIBUTES {
  public LUID Luid;
  public UInt32 Attributes;
}//LUID_AND_ATTRIBUTES

[StructLayout(LayoutKind.Sequential)]
protected struct LUID {
  public uint LowPart;
  public int HighPart;
}//LUID

int TokenInfLength = 0;
IntPtr ThisHandle = WindowsIdentity.GetCurrent().Token;
GetTokenInformation(ThisHandle, TOKEN_INFORMATION_CLASS.TokenPrivileges, IntPtr.Zero, TokenInfLength, ref TokenInfLength); //Get the TokenInformation length (returns false)
IntPtr TokenInformation = Marshal.AllocHGlobal(TokenInfLength);
if(GetTokenInformation(WindowsIdentity.GetCurrent().Token, TOKEN_INFORMATION_CLASS.TokenPrivileges, TokenInformation, TokenInfLength, ref TokenInfLength)){
  TOKEN_PRIVILEGES ThisPrivilegeSet = (TOKEN_PRIVILEGES)Marshal.PtrToStructure(TokenInformation, typeof(TOKEN_PRIVILEGES));
  //ThisPrivilegeSet now holds all of the LUID's i need to check out
  foreach(LUID_AND_ATTRIBUTES laa in ThisPrivilegeSet.Privileges){ //ThisPrivilegeSet.Privileges is only as deep as SizeConst will allow
    System.Text.StringBuilder StrBuilder = new System.Text.StringBuilder();
    int LuidNameLen = 0;
    IntPtr LuidPointer = Marshal.AllocHGlobal(Marshal.SizeOf(laa.Luid));
    Marshal.StructureToPtr(laa.Luid, LuidPointer, true);
    LookupPrivilegeName(null, LuidPointer, null, ref LuidNameLen); //Get the PrivilageName length (returns false)
    StrBuilder.EnsureCapacity(LuidNameLen + 1);
    if(LookupPrivilegeName(null, LuidPointer, StrBuilder, ref LuidNameLen)){ //StrBuilder gets the name this time
      Console.WriteLine("[{0}] : {1}", laa.Attributes.ToString(), StrBuilder.ToString());
    }//end if
    Marshal.FreeHGlobal(LuidPointer);
  }//next
}//end if

这是我的第一篇文章,对不起,如果我做错了,请向TIA寻求帮助

解决方法:

您将无法在运行时更改SizeConst,所以我认为最好的选择是检索尽可能多的内容,并仅使用所需的内容.这样,如果您需要其他信息,则以后无需更改代码.

因此,例如,如果最大特权数量为35,则将SizeConst设置为35.然后将foreach循环更改为for循环,并从i = 0转到ThisPrivilegeSet.PrivilegeCount.

这是一个示例(为此,我将SizeConst设置为8000)：

  public void RunPrivileges()
  {
     int TokenInfLength = 0;
     IntPtr ThisHandle = WindowsIdentity.GetCurrent().Token;
     GetTokenInformation(ThisHandle, TOKEN_INFORMATION_CLASS.TokenPrivileges, IntPtr.Zero, TokenInfLength, ref TokenInfLength);
     IntPtr TokenInformation = Marshal.AllocHGlobal(TokenInfLength);
     if (GetTokenInformation(WindowsIdentity.GetCurrent().Token, TOKEN_INFORMATION_CLASS.TokenPrivileges, TokenInformation, TokenInfLength, ref TokenInfLength))
     {
        TOKEN_PRIVILEGES ThisPrivilegeSet = (TOKEN_PRIVILEGES)Marshal.PtrToStructure(TokenInformation, typeof(TOKEN_PRIVILEGES));
        for (int index = 0; index < ThisPrivilegeSet.PrivilegeCount; index++ )
        { 
           LUID_AND_ATTRIBUTES laa = ThisPrivilegeSet.Privileges[index];
           System.Text.StringBuilder StrBuilder = new System.Text.StringBuilder();
           int LuidNameLen = 0;
           IntPtr LuidPointer = Marshal.AllocHGlobal(Marshal.SizeOf(laa.Luid));
           Marshal.StructureToPtr(laa.Luid, LuidPointer, true);
           LookupPrivilegeName(null, LuidPointer, null, ref LuidNameLen);
           StrBuilder.EnsureCapacity(LuidNameLen + 1);
           if (LookupPrivilegeName(null, LuidPointer, StrBuilder, ref LuidNameLen))
           {
              Console.WriteLine("[{0}] : {1}", laa.Attributes.ToString(), StrBuilder.ToString());
           }
           Marshal.FreeHGlobal(LuidPointer);
        }
     }
  }

标签：impersonation,windows-xp,marshalling,privileges,c
来源： https://codeday.me/bug/20191105/1996477.html