A Path-table Based Access Control Model for XML Database System

摘要

Current approaches for access control incur massive computational costs when XML documents are large and share the same structure. We propose a novel access control model with our prototype implementation to perform a fine-grained access control on both the structural level and the data level. The access control model has a pre-process and a runtime process to decrease runtime computational costs. During the pre-process, we compute a path-table from role/group-specified access control policy. The path-table is a table of pairings of target paths and access conditions. During the runtime process, the access condition of the requested path is looked up from the path-table and evaluated for accessibility check. Furthermore, this model supports access control on arbitrary descending paths in an XML document and also a group of arbitrary nodes that restricted by a given condition.