How to use Windows login for single-sign-on and for Active Directory entries for Desktop Java application?

Question

I'd like to have my desktop Java application to have single sign on related to Active Directory users. In two steps, I'd like to:

1. Be sure that the particular user has logged in to Windows with some user entry.
2. Check out some setup information for that user from the Active Directory

With Java: Programatic Way to Determine Current Windows User I can get the name of the current Windows user but can I rely to that? I think the

System.getProperty("user.name")

won't be secure enough? ("user.name" seems to be got from environment variables, so I can't rely on that, I think?)

Question Authenticating against Active Directory with Java on Linux provides me the authentication for given name+pass but I'd like to authenticate based on the Windows logon?

For the Active Directory access, LDAP would probably be the choice?

Answer 1

It is not supported. Java 6 has improvements, but not enough yet.

Java has its own GSS stack. The problem is for single sign-on, you need to get the Kerberos ticket from the OS (not the Java stack). Otherwise the user has to authenticate a second time (defeating the purpose of single sign-on).

Look at http://java.sun.com/developer/technicalArticles/J2SE/security/. Look down for "Access Native GSS-API" and it talks about a new system property sun.security.jgss.native which when set to true causes Java to use the underlying OS GSS implementation, giving access to the OS level authentication. Perfect!.... except its only supported for Solaris and Linux, not Microsoft Windows.

Java 6 however does appear to have enough support for acting as a server receiving SPNEGO authentication requests from IE and then authenticating that user against Active Directory. Its just the desktop client support that is still incomplete.