Approaches to formal modelling access control in PostgreSQL within framework of the MROSL DP-model

PostgreSQL is widely used in the trusted operating systems. Therefore, the scientific approaches to an implementation of the access control security in PostgreSQL have to be developed. Firstly, it is required to analyze a role-based access control (RBAC) that was originally implemented in PostgreSQL. Secondly, we have to study the mandatory access control (MAC) and the mandatory integrity control (MIC) in practice of trusted operating systems development. Now, the mandatory entity-role DP-model (MROSL DP-model) is becoming the scientific basis of access control policy in OS of Linux family, for example in OS Astra Linux Special Edition. This model includes RBAC, MAC and MIC. The model has also a hierarchical structure, which allows to supplement the model with new elements without its full processing. In addition, the model was affirmed as correct by the tools of deductive verification. This article presents the approaches that are proposed for constructing new levels within the framework of the hierarchical representation of the MROSL DP-model related to access control in PostgreSQL. At the same time, the first stage of modelling focuses on RBAC due to the significant differences between access control principals in OS Astra Linux Special Edition and PostgreSQL.