如何检查NTAccount对象是代表组还是用户?

时间:2010-08-12 04:49:21

标签: .net security winapi pinvoke

使用

返回的访问规则时
GetAccessRules(True, True, GetType(System.Security.Principal.NTAccount))

如何判断每个规则中引用的NTAccount对象是用户帐户还是组?

更新

我能够解决这个问题如下。注意,如果True是一个组,则此代码的目的是返回NTAccount,否则返回False或者在检查期间发生错误。

有更好的方法吗?

Public Function IsGroup(ByVal account As NTAccount) as Boolean  
    Dim samAccountName as string = account.Value  
    Dim accountNameParts() As String = samAccountName.Split("\")  
    If accountNameParts.Count() = 2 Then  
        Dim principalContext As PrincipalContext  
        Try  
            principalContext = New PrincipalContext(ContextType.Domain, accountNameParts(0))  
        Catch  
            Try  
                principalContext = New PrincipalContext(ContextType.Machine, accountNameParts(0))  
            Catch  
                principalContext = Nothing  
            End Try  
        End Try  
        If Not principalContext Is Nothing Then  
            Dim principal As Principal  
            principal = principal.FindByIdentity(principalContext, _samAccountName)  
            If Not principal Is Nothing then   
                return TypeOf principal Is GroupPrincipal  
            End If  
        End If  
    End If  
    Return False  
End Function

另一次更新:

上述解决方案适用于大多数服务器\帐户对象,但对于我们拥有的EMC Celerra NAS服务器上的本地组对象,它无法正常运行。我正在尝试使用NetUserGetInfo / NetLocalGroupGetInfo Win API调用来查看它是否可行,但我无法让它们正常工作。有关详细信息,请参阅NetUserGetInfo/NetLocalGroupGetInfo returning error 1722

2 个答案:

答案 0 :(得分:3)

我遇到了同样的问题。在对所有地方进行了一些研究之后,我终于找到了一个解决这个问题的合适解决方案:想法是使用WinAPI LookupAccountSid。 我已针对域名和本地帐户对此进行了测试。 Domain \ User,NT Authority \ System,MachineName \ Administrators都可以正常工作。 请注意,我没有在那里进行任何异常处理。您可以判断您的方案可接受哪种处理方式。要获得异常,可以使用System.Runtime.InteropServices.Marshal.GetLastWin32Error()

public enum PrincipalType
{
    User,
    Group
}
public bool TryGetPrincipalType(string domainQualifiedName, out PrincipalType type)
{
        var name = new StringBuilder();
        var cchName = (uint) name.Capacity;
        var referencedDomainName = new StringBuilder();
        var cchReferencedDomainName = (uint) referencedDomainName.Capacity;
        SID_NAME_USE sidType;

        var account = new NTAccount(domainQualifiedName);

        var id = new SecurityIdentifier(account.Translate(typeof (SecurityIdentifier)).Value);
        var sidBuffer = new byte[id.BinaryLength];
        id.GetBinaryForm(sidBuffer, 0);

        if (LookupAccountSid(null, sidBuffer, name, ref cchName, referencedDomainName,
                             ref cchReferencedDomainName, out sidType))
        {
            switch (sidType)
            {
                case SID_NAME_USE.SidTypeGroup:
                case SID_NAME_USE.SidTypeWellKnownGroup:
                case SID_NAME_USE.SidTypeAlias:
                    type = PrincipalType.Group;
                    return true;
                case SID_NAME_USE.SidTypeUser:
                    type = PrincipalType.User;
                    return true;
            }
        }
        type = default(PrincipalType);
        return false;
    }
private enum SID_NAME_USE
{
    SidTypeUser = 1,
    SidTypeGroup,
    SidTypeDomain,
    SidTypeAlias,
    SidTypeWellKnownGroup,
    SidTypeDeletedAccount,
    SidTypeInvalid,
    SidTypeUnknown,
    SidTypeComputer
}
[DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern bool LookupAccountSid(
        string lpSystemName,
        [MarshalAs(UnmanagedType.LPArray)] byte[] Sid,
        StringBuilder lpName,
        ref uint cchName,
        StringBuilder ReferencedDomainName,
        ref uint cchReferencedDomainName,
        out SID_NAME_USE peUse);

答案 1 :(得分:2)

答案确实是使用Windows API(NetUserGetInfoNetLocalGroupGetInfo)。

Class NetApi
    Private Declare Unicode Function NetUserGetInfo Lib "Netapi32.dll" ( _
         ByVal ServerName As String, _
         ByVal UserName As String, _
         ByVal level As Integer, _
         ByRef BufPtr As IntPtr) As Integer

    Private Declare Unicode Function NetLocalGroupGetInfo Lib "Netapi32.dll" ( _
         ByVal ServerName As String, _
         ByVal GroupName As String, _
         ByVal level As Integer, _
         ByRef BufPtr As IntPtr) As Integer

    Declare Unicode Function NetApiBufferFree Lib "netapi32.dll" _
    (ByRef buffer As IntPtr) As Long

    Public Shared Function PrincipalIsGroup(ByVal MachineName As String, ByVal AccountName As String) As String
        If String.IsNullOrEmpty(MachineName) Then
            Throw New ArgumentException("MachineName is Required")
        End If
        If String.IsNullOrEmpty(AccountName) Then
            Throw New ArgumentException("AccountName is Required")
        End If
        Dim returnValue As String = "NotFound"
        Dim bufPtr As IntPtr
        Dim lngReturn As Integer = NetLocalGroupGetInfo("\\" & MachineName, AccountName, 0, bufPtr)
        Call NetApiBufferFree(bufPtr)
        bufPtr = IntPtr.Zero
        If lngReturn = 0 Then
            returnValue = "True"
        Else
            lngReturn = NetUserGetInfo("\\" & MachineName, AccountName, 0, bufPtr)
            Call NetApiBufferFree(bufPtr)
            bufPtr = IntPtr.Zero
            If lngReturn = 0 Then
                returnValue = "False"
            End If
        End If
        Return returnValue
    End Function
End Class