Can SQL Server OpenQuery/OpenRowSet to an LDAP Linked Server be used for Authentication?

I can fetch data back from LDAPS (port 636/3269) by first creating a Linked Server using sp_addlinkedserver and sp_addlinkedsrvlogin. However, what I really need to do is to authenticate a Username/Password pair against LDAPS, to determine if the credentials are Valid. Can SQL Server be used in any way to authenticate Username/Password credentials against AD/LDAP? Is it possible to use an Extended Stored Procedure or the CLR to do this? I need to abstract this away from a .DLL because the same authentication needs to be used in a legacy application and on a website.