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Selected Areas in Cryptography 2024
Université de Québec à Montréal
August 26–30, 2024
Montréal, Québec


Schedule


Mon Aug 26
8:45 AM – 9:00 AM
Salle Polyvalente (SH-4800)

SAC Summer School - Welcome


Mon Aug 26
9:00 AM – 10:30 AM
Salle Polyvalente (SH-4800)

SAC Summer School - Quantum cryptography, Part 1

A tutorial on quantum cryptography

Anne Broadbent, University of Ottawa, Canada

Cryptographers have the difficult job of understanding and imposing limitations on adversarial behaviour. By incorporating the unique features of quantum physics, cryptographers can benefit from one of quantum physic’s fundamental properties: the quantum no-cloning theorem. This is one of the simplest yet most profound results in quantum information. According to this theorem, it is not possible to perfectly copy an unknown quantum state. In this tutorial, we will introduce the mathematical formalism that leads to quantum information and the no-cloning theorem and we will discuss some of the amazing consequences of this theorem, such as unforgeable quantum money, perfectly secure quantum communications and certified deletion.

Mon Aug 26
10:30 AM – 11:00 AM

Coffee Break


Mon Aug 26
11:00 AM – 12:15 PM
Salle Polyvalente (SH-4800)

SAC Summer School - Quantum cryptography, Part 2

A tutorial on quantum cryptography

Anne Broadbent, University of Ottawa, Canada


Mon Aug 26
12:15 PM – 1:45 PM
Salle Polyvalente (SH-4800)

Lunch (included on site)


Mon Aug 26
1:45 PM – 3:15 PM
Salle Polyvalente (SH-4800)

SAC Summer School - Cryptographic formalization and the law, Part 1

A tutorial on cryptographic formalization and the law

Aloni Cohen, University of Chicago, USA

One of the pillars of modern cryptography are rigorous definitions that capture security goals that are otherwise hard to pin down. Cryptographic formalization hones our intuitions, focuses research, and provides interfaces between math and society. This tutorial will discuss work bringing cryptographic formalism to legal questions. The goal is a feedback loop between the disciplines. First, to develop formalisms that operationalize concepts codified in law and regulation. Second, study the newly-formulated technical problem. Third, articulating the policy implications of those results. When the pieces come together, the result is a sort of legal theorem: a mathematical statement with legal consequence. The tutorial will discuss a few works along these lines --- mine and others, and of various levels of success. I plan to discuss data deletion (including machine unlearning) and data anonymization in relative depth, and other topics more briefly (e.g., copyright, compelled decryption). I will try to pull back the curtain on how the ideas developed and failures along the way.

Mon Aug 26
3:415 PM – 3:45 PM

Coffee Break


Mon Aug 26
3:45 PM – 5:00 PM
Salle Polyvalente (SH-4800)

SAC Summer School - Cryptographic formalization and the law, Part 2

A tutorial on cryptographic formalization and the law

Aloni Cohen, University of Chicago, USA

One of the pillars of modern cryptography are rigorous definitions that capture security goals that are otherwise hard to pin down. Cryptographic formalization hones our intuitions, focuses research, and provides interfaces between math and society. This tutorial will discuss work bringing cryptographic formalism to legal questions. The goal is a feedback loop between the disciplines. First, to develop formalisms that operationalize concepts codified in law and regulation. Second, study the newly-formulated technical problem. Third, articulating the policy implications of those results. When the pieces come together, the result is a sort of legal theorem: a mathematical statement with legal consequence. The tutorial will discuss a few works along these lines --- mine and others, and of various levels of success. I plan to discuss data deletion (including machine unlearning) and data anonymization in relative depth, and other topics more briefly (e.g., copyright, compelled decryption). I will try to pull back the curtain on how the ideas developed and failures along the way.





Tue Aug 27
9:00 AM – 10:30 AM
Salle Polyvalente (SH-4800)

SAC Summer School - Local differential privacy, Part 1

A tutorial on local differential privacy

Héber Arcolezi, Inria, France

This tutorial aims to provide participants with a thorough understanding of Local Differential Privacy (LDP), its applications, and its significance in safeguarding data privacy. We will start with an introduction to Differential Privacy (DP), covering its foundational concepts, including definition, post-processing, composability, and standard DP protocols. We will also explore some of its real-world deployments to provide context and relevance. Building on this foundation, we will transition into the specifics of LDP, starting with its foundational concepts. Detailed discussions will follow on building block protocols tailored for statistical analysis (e.g., mean and histogram estimation) and highlighting essential sub-tasks. Real-world deployment examples will underscore the practical utility of these mechanisms. The tutorial will then focus on adversarial analysis of LDP protocols, addressing potential privacy and security attacks and the measures to mitigate them. Additionally, we will introduce Shuffle Differential Privacy (i.e., LDP equipped with a shuffler for anonymity), exploring its primary concepts. In conclusion, we will synthesize the key insights from the tutorial, present final remarks, and discuss open questions to inspire future research and development in the field of LDP.

Tue Aug 27
10:30 AM – 11:00 AM

Coffee Break


Tue Aug 27
11:00 AM – 12:15 PM
Salle Polyvalente (SH-4800)

SAC Summer School - Local differential privacy, Part 2

A tutorial on local differential privacy

Héber Arcolezi, Inria, France


Tue Aug 27
12:15 PM – 1:15 PM
Salle Polyvalente (SH-4800)

Lunch (included on site)


Tue Aug 27
1:45 PM – 3:15 PM
Salle Polyvalente (SH-4800)

SAC Summer School - Usability and cryptography, Part 1

A tutorial on usability and cryptography

Bailey Kacsmar, University of Alberta, Canada

In this session we will scrutinize the relationship between usability and cryptography with respect to enforcing privacy and security principles. We will cover why usability matters for cryptography and how it can guide the development of novel cryptographic protocols. Throughout we will delve into methods for evaluating the usability of your system. These techniques will be illustrated with examples, including two instances of applied cryptography. Using the examples we will demonstrate how a protocol's robustness can be dependent on whether usability is considered–or not.

Tue Aug 27
3:15 PM – 3:45 PM

Coffee Break


Tue Aug 27
3:45 PM – 5:00 PM
Salle Polyvalente (SH-4800)

SAC Summer School - Usability and cryptography, Part 2

Bailey Kacsmar, University of Alberta, Canada






Wed Aug 28
8:30 AM – 9:05 AM
Salle Polyvalente (SH-4800)

Registration

Pick up your badge


Wed Aug 28
9:05 AM – 9:15 AM
Salle Polyvalente (SH-4800)

Opening Remarks

by Sébastien Gambs and Maria Eichlseder


Wed Aug 28
9:15 AM – 10:15 AM
Salle Polyvalente (SH-4800)

Invited Lecture - Online Age Verification, and Privacy Protection: An impossible Equation?

Olivier Blazy, École Polytechnique, France

The internet, often described as a vast and unruly wilderness, presents a universal challenge: maintaining safety and order. A key concern is the protection of children online, specifically through restricting their access to sensitive content. Various methods of online age verification have been attempted, ranging from highly intrusive techniques to those that are less effective. In this presentation, we will delve into the common pitfalls associated with traditional age verification methods both in term of safety, and security. We will then introduce a new framework developed in collaboration with the French Data Protection Authority (CNIL) and PEReN. This framework utilizes readily available technologies and offers a practical implementation approach. We will discuss how this proof of concept not only addresses specific challenges but also aligns with current legislative measures in various, and expectations while contributing to a safer and more privacy-friendly digital environment.

Wed Aug 28
10:15 AM – 10:45 AM

Coffee Break


Wed Aug 28
10:45 AM – 12:00 PM
Salle Polyvalente (SH-4800)

Post-quantum cryptography

BUFFing FALCON without Increasing the Signature Size
by Samed Düzlü, Rune Fiedler and Marc Fischlinpre-proceeding version (PDF)slides

SILBE: an Updatable Public Key Encryption Scheme from Lollipop Attacks
by Max Duparc, Tako Boris Fouotsa and Serge Vaudenaypre-proceeding version (PDF)slides

Towards Optimally Small Smoothness Bounds for Cryptographic-Sized Smooth Twins and their Isogeny-based Applications
by Bruno Sternerpre-proceeding version (PDF)slides


Wed Aug 28
12:00 PM – 1:30 PM

Lunch Break

(not included)


Wed Aug 28
1:30 PM – 2:20 PM
Salle Polyvalente (SH-4800)

Symmetric primitive design

Koala: A Low-Latency Pseudorandom Function
by Yanis Belkheyar, Parisa Amiri Eliasi, Joan Daemen, Santosh Ghosh, Daniël Kuijsters, Alireza Mehrdad, Silvia Mella, Shahram Rasoolzadeh and Gilles Van Asschepre-proceeding version (PDF)slides

Minimize the Randomness in Rasta-Like Designs: How Far Can We Go? Application to PASTA
by Lorenzo Grassi, Fukang Liu, Christian Rechberger, Fabian Schmid, Roman Walch and Qingju Wangpre-proceeding version (PDF)slides


Wed Aug 28
2:20 PM – 3:10 PM
Salle Polyvalente (SH-4800)

Symmetric cryptanalysis

A Univariate Attack against the Limited-Data Instance of Ciminion
by Augustin Bariantpre-proceeding version (PDF)slides

Improved Algebraic Attacks on Round-Reduced LowMC with Single-Data Complexity
by Xingwei Ren, Yongqiang Li and Mingsheng Wangpre-proceeding version (PDF)slides


Wed Aug 28
3:10 PM – 3:40 PM

Coffee Break


Wed Aug 28
3:40 PM – 4:55 PM
Salle Polyvalente (SH-4800)

Privacy-preserving cryptography I

Revisiting Oblivious Top-k Selection with Applications to Secure k-NN Classification
by Kelong Cong, Robin Geelen, Jiayi Kang and Jeongeun Parkpre-proceeding version (PDF)slides

Simulation Secure Multi-Input Quadratic Functional Encryption
by Ferran Alborch Escobar, Sébastien Canard and Fabien Laguillaumiepre-proceeding version (PDF)slides

Generation of Authenticated Secret-Shared Scaled Unit Vectors for Beaver Triples
by Vincent Riederpre-proceeding version (PDF)slides


Wed Aug 28
6:00 - 9:00 PM
Espace St-Denis, salle Marie-Louise

Reception






Thu Aug 29
9:25 AM – 10:15 AM
Salle Polyvalente (SH-4800)

Privacy-preserving cryptography II

Multi-Key Homomorphic Encryption with Threshold Re-Encryption
by Akira Nakashima, Yukimasa Sugizaki, Hikaru Tsuchida, Takuya Hayashi, Koji Nuida, Kengo Mori and Toshiyuki Isshikipre-proceeding version (PDF)slides

Multi-User Dynamic Searchable Encryption for Prefix-Fixing Predicates from Symmetric-Key Primitives
by Takato Hirano, Yutaka Kawai, Yoshihiro Koseki, Satoshi Yasuda, Yohei Watanabe, Takumi Amada, Mitsugu Iwamoto and Kazuo Ohtapre-proceeding version (PDF)slides


Thu Aug 29
10:15 AM – 10:45 AM

Coffee Break


Thu Aug 29
10:45 AM – 12:00 PM
Salle Polyvalente (SH-4800)

Public-key cryptanalysis

Bias from Uniform Nonce: Revised Fourier Analysis-based Attack on ECDSA
by Shunsuke Osaki and Noboru Kunihiropre-proceeding version (PDF)slides

Multivariate Blind Signatures Revisited
by Ward Beullenspre-proceeding version (PDF)slides

Post-Quantum Backdoor for Kyber-KEM
by Wenwen Xia, Geng Wang and Dawu Gupre-proceeding version (PDF)slides


Thu Aug 29
12:00 PM – 1:30 PM

Lunch Break

(not included)


Thu Aug 29
1:30 PM – 2:20 PM
Salle Polyvalente (SH-4800)

Identity-based encryption

Identity-Based Encryption from Lattices with More Compactness in the Standard Model
by Weidan Ji, Zhedong Wang, Haoxiang Jin, Qi Wang, Geng Wang and Dawu Gupre-proceeding version (PDF)slides

Oblivious Identity-based Encryption (IBE Secure Against an Adversarial KGC)
by Katerina Mitrokotsa, Sayantan Mukherjee and Jenit Tomypre-proceeding version (PDF)slides


Thu Aug 29
2:20 PM – 3:10 PM
Salle Polyvalente (SH-4800)

Implementations and Side-channel analysis

Modular Multiplication in the AMNS representation : Hardware Implementation
by Louis Noyez, Nadia El Mrabet, Olivier Potin and Pascal Veronpre-proceeding version (PDF)slides

Train Wisely: Multifidelity Bayesian Optimization Hyperparameter Tuning in Deep Learning-based Side-Channel Analysis
by Trevor Hong Eng Yap, Shivam Bhasin and Léo Weissbartpre-proceeding version (PDF)slides


Thu Aug 29
3:10 PM – 3:40 PM

Coffee Break


Thu Aug 29
3:40 PM – 4:55 PM
Salle Polyvalente (SH-4800)

Symmetric design paradigms

Classical and Quantum Generic Attacks on 6-round Feistel Schemes
by Maya Chartouny, Benoît Cogliati and Jacques Patarinpre-proceeding version (PDF)slides

Weightwise (almost) perfectly balanced functions based on total orders
by Pierrick Méauxpre-proceeding version (PDF)slides

Generalized Triangular Dynamical System: An Algebraic System for Constructing Cryptographic Permutations over Finite Fields
by Arnab Roy and Matthias Johann Steinerpre-proceeding version (PDF)slides


Thu Aug 29
7:00 PM – 10:00 PM
ITHQ, salle Mont-Royal

Banquet






Fri Aug 30
9:15 AM – 10:15 AM
Salle Polyvalente (SH-4800)

Stafford Tavares Invited Lecture - Relativistic Zero-Knowledge Proofs

Claude Crépeau, McGill University, Canada

Zero-Knowledge proofs have proved useful in various cryptographic applications. Perfect zero-knowledge proofs are best since they provide the ultimate level of security of the data involved. Recently, such proofs have been deployed under the assumption that several provers are kept at a distance from each other taking advantage of special relativity as a source of security. This talk will review the existing results in this research area including work of the author with provers at a distance of 60m from each other.

Fri Aug 30
10:15 AM – 10:45 AM

Coffee Break


Fri Aug 30
10:45 AM – 12:00 PM
Salle Polyvalente (SH-4800)

Authenticated encryption

Generic Security of the Ascon Mode: On the Power of Key Blinding
by Charlotte Lefevre and Bart Menninkpre-proceeding version (PDF)slides

Fast Parallelizable Misuse-Resistant Authenticated Encryption: Low Latency (Decryption-Fast) SIV
by Mustafa Khairallahpre-proceeding version (PDF)slides

Provably Secure Online Authenticated Encryption and Bidirectional Online Channels
by Arghya Bhattacharjee, Ritam Bhaumik, Daniel Collins, and Mridul Nandipre-proceeding version (PDF)slides