Validation of Security-Design Models using Z
Résumé
This paper is aimed at formally specifying and validating security-design models of an information system. It combines graphical languages and formal methods, integrating specification languages such as UML and an extension, SecureUML, with the Z language. The modeled system addresses both functional and security requirements of a given application. The formal functional specification is built automatically from the UML diagram, using our RoZ tool. The secure part of the model instanciates a generic security-kernel written in Z, free from applications specificity, which models the concepts of RBAC (Role-Based Access Control). The final modeling step creates a link between the functional model and the instanciated security kernel. Validation is performed by animating the model, using the Jaza tool. Our approach is demonstrated on a case-study from the health care sector where confidentiality and integrity appear as core challenges to protect medical records.