protected WSFederationRegisteredService getWsFederationRegisteredService(final Service targetService) {
        val svc = configContext.getServicesManager().findServiceBy(targetService, WSFederationRegisteredService.class);
        RegisteredServiceAccessStrategyUtils.ensureServiceAccessIsAllowed(targetService, svc);
        return svc;
    }
Gets security token from request.

@param request the request
@return the security token from request
support/cas-server-support-ws-idp/src/main/java/org/apereo/cas/ws/idp/web/BaseWSFederationRequestController.java