@Vinit_ParadoX, In Openfire the plugins are loaded by a separate classloader (a child of Openfire’s main classloader)in Openfire, so that means that plugins will not have the rights to access all API/methods/functions/objects… of Openfire during runtime. And for authentication you need to access low-level code of Openfire. (See this Custom authProvider class not found when deploying plugin)
@gauravdalela, if you want a “real” SSO like CAS, OAuth, SAMLv2… then you will have to implement it in Openfire because currently it doesn’t exist.