1. A storage system comprising: nodes coupled to one another via a network; storage devices coupled to the nodes; a file attribute detecting module that detects one or more file attributes; a file access rule information storing unit that stores information about one or more file access rules that are associated with the file attribute; and a file access control module that controls access to a file in the storage devices in conformity with the one or more file access rules that are associated with the detected one or more file attributes.