Progress in cryptology -- AFRICACRYPT 2020 : 12th International Conference on Cryptology in Africa, Cairo, Egypt, July 20-22, 2020, Proceedings / Abderrahmane Nitaj, Amr Youssef (eds.).

International conference proceedings.

Includes author index.

Online resource; title from PDF title page (SpringerLink, viewed July 24, 2020).

Intro -- Preface -- Organization -- Contents -- Zero Knowledge -- QA-NIZK Arguments of Same Opening for Bilateral Commitments -- 1 Introduction -- 1.1 Our Results -- 1.2 Our Techniques -- 2 Preliminaries -- 2.1 Quasi-Adaptive Non-interactive Zero-Knowledge Proofs -- 2.2 Assumptions -- 3 Linear Relations in a Bilinear Group -- 3.1 Algebraic Commitment Schemes -- 3.2 Linear Equations in a Bilinear Group -- 4 Non-aggregated Scheme -- 5 Aggregated Scheme -- 6 Optimality of Our Constructions -- References -- Signatures of Knowledge for Boolean Circuits Under Standard Assumptions -- 1 Introduction

1.1 Our Contribution -- 2 Preliminaries -- 2.1 Definitions -- 2.2 Boolean Circuits -- 2.3 Aggregated Proofs of Quadratic Equations -- 2.4 Aggregated Proofs of Linear Equations -- 3 SE NIZK Argument for Boolean CircuitSat -- 3.1 Concrete USES QA-NIZK for Boolean CircuitSat -- 3.2 Universally Composable Signature of Knowledge -- 4 USS QA-NIZK Arguments of Knowledge Transfer for Linear Spaces -- 4.1 USS LinDk Argument -- 4.2 USS BLinDk Argument -- References -- LESS is More: Code-Based Signatures Without Syndromes -- 1 Introduction -- 2 Preliminaries -- 2.1 Coding Theory

2.2 Identification Schemes and Zero-Knowledge Protocols -- 3 The Code Equivalence Problem -- 3.1 Hardness -- 4 Protocol Description -- 5 Security Analysis -- 5.1 Leon's Algorithm -- 5.2 The Support Splitting Algorithm -- 5.3 Application to Linear Code Equivalence -- 6 Quantum Attacks on the Code Equivalence Problem -- 7 Signature Scheme -- 8 Concrete Instances -- 8.1 Choice of Parameters -- 8.2 Performance and Comparison -- 9 Conclusion -- References -- UC Updatable Databases and Applications -- 1 Introduction -- 2 Modular Design and FNIC -- 3 Functionality FUD -- 4 Construction UD

4.1 Building Blocks -- 4.2 Description of UD -- 5 Instantiation and Efficiency Analysis -- 5.1 UC ZK Proof for Relation R -- 5.2 Efficiency Analysis -- 5.3 Implementation and Efficiency Measurements -- 6 Modular Design with FUD and Applications -- 7 Related Work -- 8 Conclusion and Future Work -- References -- Symmetric Key Cryptography -- Impossible Differential Cryptanalysis of Reduced-Round Tweakable TWINE -- 1 Introduction -- 2 Specifications of T-TWINE -- 3 An Impossible Differential Distinguisher of T-TWINE -- 3.1 Observations

4 Impossible Differential Key-Recovery Attack on 27-Round T-TWINE-128 -- 5 Impossible Differential Key-Recovery Attack on 25-Round T-TWINE-80 -- 6 Conclusion -- A 18-round Impossible Differential Characteristic as Depicted in Figure8 of ch510.1007sps978sps3sps030sps26834sps3sps8 -- References -- MixColumns Coefficient Property and Security of the AES with A Secret S-Box -- 1 Introduction -- 1.1 Our Contribution -- 2 Preliminary -- 2.1 Description of the AES -- 2.2 Notations -- 2.3 Exchange Attack -- 3 Improved Key-Recovery Attack Based on Property 1

This book constitutes the refereed proceedings of the 12th International Conference on the Theory and Application of Cryptographic Techniques in Africa, AFRICACRYPT 2020, held in Cairo, Egypt, in July 2020. The 21 papers presented in this book were carefully reviewed and selected from 49 submissions. The papers are organized in topical sections on zero knowledge, symmetric key cryptography, elliptic curves, post quantum cryptography, lattice based cryptography, side channel attacks, cryptanalysis and new algorithms and schemes. AFRICACRYPT is a major scientific event that seeks to advance and promote the field of cryptology on the African continent. The conference has systematically drawn some excellent contributions to the field. The conference has always been organized in cooperation with the International Association for Cryptologic Research (IACR).