Quantum resistance on modes of operation in block ciphers

Abstract

The security of the existing cryptosystems is no longer guaranteed against quantum adversaries. The research on quantum security of cryptosystems, therefore, should be thoroughly investigated. In this research, as one of the most widely used cryptographic primitives, confidentiality modes of operation in block ciphers are examined: CBC, IGE, CFB, OFB, and CTR. First, quantum adversaries are classified as Q0, Q1, and Q2 depending on their ability to perform quantum computation. The corresponding new quantum proof techniques are also presented. Then the underlying block ciphers are assumed as pseudorandom functions which are Q0, Q1, and Q2 secure. Also, modes of operation to be investigated are represented in the quantum circuit. Next, our desired security notions are considered in terms of quantum version of indistinguishability (IND) and chosen-plaintext attack (CPA): IND under quantum CPA (IND-qCPA), weak-quantum IND under quantum CPA (wqIND-qCPA), and quantum IND under quantum CPA (qIND-qCPA). In conclusion, the security of each mode in Q0-, Q1-, or Q2-secure block ciphers is analysed and compared in these various quantum security game scenarios.

Since quantum computing was proposed in the early 1980s, quantum computers and their novel algorithms have been developed. There are known advantages that quantum computers have over classical computers due to their quantum-mechanical properties using qubits. The fact that there may be more powerful adversaries capable of quantum computation has had a huge impact on the field of cryptography