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International Journal of Scientific Research in Computer Science Engineering and Information Technology

Secure Messaging Using Post-Quantum Key Sharing Based on CSIDH and Fujisaki-Okamoto Transform

Rakotondramanana Radiarisainana Sitraka, Ramafiarisona Hajasoa Malalatiana, Randrianandrasana Marie Emile, Henintsoa Stephana Onjaniaiana

Published Mar 25, 2024• 0 citations
Publisher

Abstract

Preserving the confidentiality of information exchanges relies fundamentally on an end-to-end encryption system, involving the use of a secret key to secure the entire communication. However, with the imminent emergence of quantum computing, threats to traditional encryption systems are multiplying. This is where post-quantum key sharing, in particular the Commutative Super Isogenies Diffie Hellman (CSIDH) algorithm, comes in. The CSIDH uses the ideal of some class number to a morphism of elliptic curve for calculating the shared key. It offers an innovative solution for secure key generation between two users, while providing a robust defense against potential attacks from quantum computers, whose computing power is redefining the limits of cryptographic security, based on the mathematical foundations of elliptic curves and isogeny. This technological advance represents an essential pillar in preserving the confidentiality of communications, in a context where security challenges are constantly evolving. Combining with Fujisaki-Okamoto transform, socket, and Linux; a chat application over python could be created for transmitting secure messages.

DOI
10.32628/cseit2410213

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Preserving the confidentiality of information exchanges relies fundamentally on an end-to-end encryption system, involving the use of a secret key to secure the entire communication. However, with the imminent emergence of quantum computing, threats to traditional encryption systems are multiplying. This is where post-quantum key sharing, in particular the Commutative Super Isogenies Diffie Hellman (CSIDH) algorithm, comes in. The CSIDH uses the ideal of some class number to a morphism of elliptic curve for calculating the shared key. It offers an innovative solution for secure key generation between two users, while providing a robust defense against potential attacks from quantum computers, whose computing power is redefining the limits of cryptographic security, based on the mathematical foundations of elliptic curves and isogeny. This technological advance represents an essential pillar in preserving the confidentiality of communications, in a context where security challenges are constantly evolving. Combining with Fujisaki-Okamoto transform, socket, and Linux; a chat application over python could be created for transmitting secure messages.
This paper presents the design and implementation of an Internet-based instant messaging application that leverages post-quantum cryptographic algorithms founded on isogenies of elliptic curves. The system employs the CSIDH cryptosystem for key exchange and SeaSign for digital signatures, integrating these with the X3DH and Double-Ratchet protocols to enable end-to-end encryption for both text messages and binary file transfers. Key generation is supported for new users upon registration, ensuring robust cryptographic foundations from the outset. The performance of the CSIDH and SeaSign algorithms is evaluated at various security levels using a Python-based prototype, providing practical benchmarks. By combining isogeny-based cryptographic schemes with widely adopted secure messaging protocols, this work presents an illustration of a selected quantum-resistant communication solution and offers insights into the feasibility and practicality of deploying such protocols in real-world applications.
The Signal protocol can be considered state-of-the-art when it comes to secure messaging, but advances in quantum computing stress the importance of finding post-quantum resistant alternatives to its asymmetric cryptographic primitives. The aim is to determine whether existing post-quantum cryptography can be used as a drop-in replacement for the public-key cryptography currently used in the Signal protocol and what the performance trade-offs may be. An implementation of the Signal protocol using commutative supersingular isogeny Diffie-Hellman (CSIDH) key exchange operations in place of elliptic-curve Diffie-Hellman (ECDH) is proposed. The benchmark results on a Samsung Galaxy Note 8 mobile device equipped with a 64-bit Samsung Exynos 9 (8895) octa-core CPU shows that it takes roughly 8 seconds to initialize a session using CSIDH-512 and over 40 seconds using CSIDH-1024, without platform specific optimization. To the best of our knowledge, the proposed implementation is the first post-quantum resistant Signal protocol implementation and the first evaluation of using CSIDH as a drop-in replacement for ECDH in a communication protocol.
Widely used communication and messaging protocols, e.g., TLS 1.3 and Signal, are insecure against an adversary with a quantum computer. We expect that post-quantum security will become mandatory for a new generation of cryptographic protocols in the nearest 10-15 years. The analysis of existing post-quantum secure cryptographic tools for key exchange, encryption and message authentication based on hard problems in codes, lattices, ring learning with errors and elliptic curve isogenies revealed their advantages and drawbacks. In particular, we conclude, that the main threat to communication and messaging protocols is only pre-quantum security of currently used Diffie-Hellman key exchange protocols. We summarize efficiency and safety results for each class of post-quantum cryptographic schemes and present an experimental implementation of isogeny-based Diffie-Hellman-like key exchange protocol as an illustration of their applicability.
Abstract - In the emerging era of quantum computing, traditional cryptographic algorithms such as RSA and Elliptic Curve Cryptography (ECC) are at risk from quantum-based attacks. These developments pose a significant threat to secure network communication systems that rely on classical key exchange mechanisms. To overcome this challenge, the proposed work introduces a Hybrid Quantum-Resistant Key Exchange Protocol that combines the strengths of both classical andpost-quantum cryptographic algorithms. The hybrid approach integrates Elliptic Curve Dif ie–Hellman (ECDH) with alattice-based post-quantum algorithm, Kyber, to establish a shared session key between communicating entities. This sharedkeyisthen utilized for symmetric encryption using AES to ensure confidentiality and data integrity. The system is implementedusingPython socket programming to demonstrate secure data transmission between client and server. Performance is analyzedinterms of key generation time, encryption and decryption speed, key size, and computational ef iciency. The results validatethatthe proposed hybrid model provides enhanced resistance against quantum attacks while maintaining acceptable performance, making it suitable for future secure communication systems. Keywords - elliptic curve dif ie–hellman, hybrid key exchange, kyber, post-quantum cryptography, quantum computing.
In this paper, a technique to develop a secure messaging service utilizing a new post-quantum cryptosystem, termed CryptoMess, is proposed. Commutative Supersingular Isogeny Diffie-Hellman (CSIDH) is utilized to secure key exchange paired with the AES algorithm to protect message content in communication. At the same time, the Rainbow post-quantum digital signature technology is incorporated to assure the integrity and authenticity of communications between the sender and the recipient. As a consequence, the messaging program is able to exchange messages between users, assuring safety, security, integrity, and authenticity. The performance of the program has a transmitting rate of approximately 0.26 s and a receiving rate of approximately 0.22 s. The message signing time is approximately 0.027 s, the message verification speed is approximately 0.22 s, and the key exchange time is approximately 0.0017s.
Quantum key cryptography is the cryptography that has capability to overcome the threat of quantum computing in future when exploited by adversaries. With quantum computers in the hands of adversaries in future, the existing security schemes might be broken due to massive computing power. As security is not one-time effort, it is a continuous process that needs development of stronger security schemes. Existing PQC schemes focused on either data security or key exchange. Besides, there is need for further improvement towards enhanced PQC primitives. In this paper, we proposed an integrated cloud data security framework with novel schemes towards PQC. For data security with encryption and decryption, we proposed Hybrid Encoding and Data Transformation (HEDT) algorithm. Another key exchange security scheme called Elliptic Curve Super singular Isogeny Diffie–Hellman (ECSIDH) was developed. The key agreement scheme consists of Elliptic-Curve Diffie–Hellman (ECDH) and Super singular Isogeny Diffie–Hellman (SIDH). ECDH combined with SIDH candidate in PQC which enhances the security of the proposed scheme since they strengthen the ECDH with PQC candidate SIDH. The ECSIDH is found more secure than individual key exchange scheme such as SIDH. Security analysis of HEDT revealed that it is more secure than existing algorithms and ECSIDH is more secure PQC candidate.