application auth as enterprise user via SSO to validate access

I'm sure someone has done this before and I'm just not searching correctly to find the answer, but I have an application that allows people to provide links to files they have shared via box.  My application needs to authenticate against Box as a user within the company to validate that the link the person has provided has been shared correctly such that people within the company have access to it.  There must be a way to perform the necessary auth and attempt to access the shared url to validate that company users can access the file.  Oh, and did I mention my company uses Enterprise SSO to access Box?   Any guidance and/or sample code would be greatly appreciated.