A policy storage stores an access control policy as a set of setting information items to make resources (access destinations) shared by an adhoc group. When a part of the access control policy is edited, a policy analyzer updates a rule generated from the edited access control policy. At this time, the rule is updated with use of object knowledge having a data configuration capable of expressing a user as belonging to plural user groups. An access control list setting means updates a part of an access control list, based on the updated rule. Accordingly, an access control list can be generated with respect to a user group including a user who belongs to plural organizations, and the access control list can be updated efficiently.