Publication

PAE: Towards More Efficient and BBB-Secure AE from a Single Public Permutation

Publications associées (29)

Secure and Efficient Cryptographic Algorithms in a Quantum World

Since the advent of internet and mass communication, two public-key cryptographic algorithms have shared the monopoly of data encryption and authentication: Diffie-Hellman and RSA. However, in the last few years, progress made in quantum physics -- and mo ...

EPFL2024

An Ultra-High Throughput AES-Based Authenticated Encryption Scheme for 6G: Design and Implementation

Andrea Felice Caforio, Subhadeep Banik

In this paper, we propose Rocca-S, an authenticated encryption scheme with a 256-bit key and a 256-bit tag targeting 6G applications bootstrapped from AES. Rocca-S achieves an encryption/decryption speed of more than 200 Gbps in the latest software environ ...

Springer International Publishing Ag2024

On the Theory and Practice of Modern Secure Messaging

Daniel Patrick Collins

Billions of people now have conversations daily over the Internet. A large portion of this communication takes place via secure messaging protocols that offer "end-to-end encryption'" guarantees and resilience to compromise like the widely-used Double Ratc ...

EPFL2024

BBB security for 5-round even-Mansour-based key-alternating Feistel ciphers

Ritam Bhaumik

In this paper, we study the security of the Key-Alternating Feistel (KAF) ciphers, a class of key alternating ciphers with the Feistel structure, where each round of the cipher is instantiated with n-bit public round permutation Pi\documentclass[12pt]{mini ...

SPRINGER2023

Green Cryptography and Other Optimisations

Andrea Felice Caforio

The spectral decomposition of cryptography into its life-giving components yields an interlaced network of tangential and orthogonal disciplines that are nonetheless invariably grounded by the same denominator: their implementation on commodity computing p ...

EPFL2023

Security in the Presence of Quantum Adversaries

Khashayar Barooti

With the looming threat of large-scale quantum computers, a fair portion of recent cryptographic research has focused on examining cryptographic primitives from the perspective of a quantum adversary. Shor's 1994 result revealed that quantum computers can ...

EPFL2023

Revisiting the Indifferentiability of the Sum of Permutations

Ritam Bhaumik

The sum of two n-bit pseudorandom permutations is known to behave like a pseudorandom function with n bits of security. A recent line of research has investigated the security of two public n-bit permutations and its degree of indifferentiability. Mandal e ...

Springer2023

Public-Key Encryption with Quantum Keys

Khashayar Barooti

In the framework of Impagliazzo's five worlds, a distinction is often made between two worlds, one where public-key encryption exists (Cryptomania), and one in which only one-way functions exist (MiniCrypt). However, the boundaries between these worlds can ...

Springer International Publishing Ag2023

Private Message Franking with After Opening Privacy

Serge Vaudenay, Iraklis Leontiadis

Recently Grubbs et al. [GLR17] initiated the formal study of message franking protocols. This new type of service launched by Facebook, allows the receiver in a secure messaging application to verifiably report to a third party an abusive message some send ...

2023

The Side-channel Metrics Cheat Sheet

Francesco Regazzoni, Mirjana Stojilovic, Dorian Ros, Ognjen Glamocanin

Side-channel attacks exploit a physical observable originating from a cryptographic device in order to extract its secrets. Many practically relevant advances in the field of side-channel analysis relate to security evaluations of cryptographic functions a ...

2023

On Quantum Secure Compressing Pseudorandom Functions

Ritam Bhaumik

In this paper we characterize all 2n-bit-to-n-bit Pseudorandom Functions (PRFs) constructed with the minimum number of calls to n-bit-to-n-bit PRFs and arbitrary number of linear functions. First, we show that all two-round constructions are either classic ...

2023

Optimal Symmetric Ratcheting for Secure Communication

Serge Vaudenay, Andrea Felice Caforio, Daniel Patrick Collins, Hailun Yan

To mitigate state exposure threats to long-lived instant messaging sessions, ratcheting was introduced, which is used in practice in protocols like Signal. However, existing ratcheting protocols generally come with a high cost. Recently, Caforio et al. pro ...

OXFORD UNIV PRESS2022

Attacks on some post-quantum cryptographic protocols: The case of the Legendre PRF and SIKE

Novak Kaluderovic

Post-quantum cryptography is a branch of cryptography which deals with cryptographic algorithms whose hardness assumptions are not based on problems known to be solvable by a quantum computer, such as the RSA problem, factoring or discrete logarithms. This ...

EPFL2022

Analysis and Improvements of the Sender Keys Protocol for Group Messaging

Daniel Patrick Collins

Messaging between two parties and in the group setting has enjoyed widespread attention both in practice, and, more recently, from the cryptographic community. One of the main challenges in the area is constructing secure (end-to- end encrypted) and effici ...

2022

Secret Key Generation Using Short Blocklength Polar Coding Over Wireless Channels

Yanina Yurina Shkel

This paper investigates the problem of secret key generation from correlated Gaussian random variables in the short blocklength regime. Short blocklengths are commonly employed in massively connected IoT sensor networks in 5G and beyond wireless systems. P ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Serial Lightweight Implementation Techniques for Block Ciphers

Muhammed Fatih Balli

Most of the cryptographic protocols that we use frequently on the internet are designed in a fashion that they are not necessarily suitable to run in constrained environments. Applications that run on limited-battery, with low computational power, or area ...

EPFL2021

Complete Practical Side-Channel-Assisted Reverse Engineering of AES-Like Ciphers

Andrea Felice Caforio, Muhammed Fatih Balli, Subhadeep Banik

Public knowledge about the structure of a cryptographic system is a standard assumption in the literature and algorithms are expected to guarantee security in a setting where only the encryption key is kept secret. Nevertheless, undisclosed proprietary cry ...

SPRINGER INTERNATIONAL PUBLISHING AG2022

Orthros: A Low-Latency PRF

Subhadeep Banik

We present Orthros, a 128-bit block pseudorandom function. It is designed with primary focus on latency of fully unrolled circuits. For this purpose, we adopt a parallel structure comprising two keyed permutations. The round function of each permutation is ...

2021

A Deeper Look at the Energy Consumption of Lightweight Block Ciphers

Francesco Regazzoni, Andrea Felice Caforio, Muhammed Fatih Balli, Subhadeep Banik

In the last few years, the field of lightweight cryptography has seen an influx in the number of block ciphers and hash functions being proposed. In the past there have been numerous papers that have looked at circuit level implementation of block ciphers ...

IEEE2021

Atom: A Stream Cipher with Double Key Filter

Willi Meier, Andrea Felice Caforio, Subhadeep Banik

It has been common knowledge that for a stream cipher to be secure against generic TMD tradeoff attacks, the size of its internal state in bits needs to be at least twice the size of the length of its secret key. In FSE 2015, Armknecht and Mikhalev however ...

2021