Networking and cryptography library with a non-repudiation flavor for blockchain

Abstract

Blockchain is currently one of the most widely discussed inventions in the information and communication technology industry. It is a pillar of the fourth industrial revolution and it is a cryptographically demanding technology that is regarded as one of the most influential topics in academia. Many blockchain platforms currently utilize third-party cryptographic libraries that offer many cryptographic primitives in order to ensure users' protection against cyber-attacks. The Networking and Cryptography library (NaCl) is an open-source library for cryptographic primitives. NaCl is known to be one of the best libraries that provide usability property. Although NaCl is easy to use and ensures: confidentiality, integrity, and authenticity, it fails to provide the non-repudiation service. In this paper, an improvement to the blockchain platforms is proposed by enhancing the NaCl library to achieve the non-repudiation property that enhances the security level of the implemented blockchain platform. In NaCl, to provide the aforementioned security services, messages are signed and then encrypted. Therefore, the non-repudiation service is not provided. In this paper, the proposed solution is based on adding a signature block to enable a non-repudiation property. First, logical analysis is conducted using the BAN logic on the NaCl library to prove that it does not provide the non-repudiation property. Subsequently, a modification to the library is proposed, and the correctness of the proposed solution is proven using BAN logic. The analysis suggests that the proposed solution fixes the aforementioned problem.