Mandatory access control method application for smart contracts

Abstract

The task of access control in distributed information systems utilizing smart contracts is considered. A concise review of the main access control approaches — mandatory, role-based, and discretionary — is presented, along with their key features and limitations. Particular attention is paid to the access control approach based on mandatory access control (MAC). Known access control approaches applied in both traditional non-distributed and distributed information systems utilizing smart contracts are analyzed. The peculiarities of these distributed information systems that influence access control decisions are identified. Based on these peculiarities, the drawbacks of the discretionary and role-based approaches are determined, and the mandatory approach is proposed. To formalize the approach, a mathematical description of MAC for smart contracts is provided. To demonstrate the concept, several examples of implementing this mathematical description are presented in the form of Solidity code fragments: a direct naive implementation, an implementation using modifiers, and an implementation based on a dedicated access manager contract. The code is described, its main idea is explained, and possible directions for further scaling of these code fragments are outlined. Based on the analysis of the proposed applications, the modifier-based implementation of MAC is identified as the most efficient in terms of computational resources, while the access manager approach is considered the most scalable. The latter approach is proposed for complex distributed systems involving multiple smart contracts. The results of the experimental study are presented to compare the performance indicators of the proposed access control implementations with known implementations. Prospects for further research aimed at improving access control in distributed information systems utilizing smart contracts are identified.