Research

My primary research interest is the provable security analysis of symmetric-key cryptographic modes using combinatorial techniques. My doctoral research focused on provable security against a classical adversary. At Inria, I started exploring the exciting new field of provable security against a quantum adversary, as part of the ERC project QUASYModo. At present I am studying proof frameworks for adapting classical counting techniques in post-quantum security proofs.

My complete academic CV (last updated in September 2024) can be found here: [PDF] link to CV. My publications are also listed on my DBLP page.

Publications

Block Cipher Doubling for a Post-Quantum World.
Communications in Cryptology 1(3) (to appear).
(with André Chailloux, Paul Frixons, Bart Mennink and María Naya-Plasencia)

Mind the Bad Norms: Revisiting Compressed Oracle-based Quantum Indistinguishability Proofs.
Asiacrypt '24 (to appear).
(with Benoît Cogliati, Jordan Ethan and Ashwin Jha)

Efficient Variants of TNT with BBB Security.
ProvSec '24 (to appear).
(with Bishwajit Chakraborty, Wonseok Choi, Avijit Dutta, Cuauhtemoc Mancillas López, Hrithik Nandi and Yaobin Shen)

Indifferentiability of Confusion-Diffusion Networks.
SCN '24 (to appear).
(with Mridul Nandi, Sayantan Paul and Abishanka Saha)

Provably Secure Online Authenticated Encryption and Bidirectional Online Channel.
SAC '24 (to appear).
(with Arghya Bhattacharjee, Daniel Collins and Mridul Nandi)

The Committing Security of MACs with Applications to Generic Composition.
Crypto '24.
(with Bishwajit Chakraborty, Wonseok Choi, Avijit Dutta, Jérôme Govinden and Yaobin Shen)

On Quantum-Secure Compressing Pseudorandom Functions.
Asiacrypt '23.
(with Benoît Cogliati, Jordan Ethan and Ashwin Jha)

BBB-Security for 5-Round Even-Mansour-Based Key-Alternating Feistel Ciphers.
Designs, Codes and Cryptography 92(1).
(with Arghya Bhattacharjee, Avijit Dutta, Mridul Nandi and Anik Raychaudhuri)

PAE: Towards More Efficient and BBB-secure AE From a Single Public Permutation.
ICICS '23.
(with Arghya Bhattacharjee, Avijit Dutta and Eik List)

Revisiting the Indifferentiability of the Sum of Permutations.
Crypto '23.
(with Aldo Gunsing, Ashwin Jha, Bart Mennink and Yaobin Shen)

Offset-Based BBB-Secure Tweakable Block-ciphers with Updatable Caches.
Indocrypt '22.
(with Arghya Bhattacharjee and Mridul Nandi)

A Sponge-Based PRF with Good Multi-user Security.
SAC '22.
(with Arghya Bhattacharjee and Mridul Nandi)

Improved indifferentiability security proof for 3-round tweakable Luby-Rackoff.
Designs, Codes and Cryptography 89(10).
(with Mridul Nandi and Anik Raychaudhuri)

QCB: Efficient Quantum-Secure Authenticated Encryption.
Asiacrypt '21.
(with Xavier Bonnetain, André Chailloux, Gaëtan Leurent, María Naya-Plasencia, André Schrottenloher and Yannick Seurin)

ZCZ - Achieving n-bit SPRP Security with a Minimal Number of Tweakable-Block-Cipher Calls.
Asiacrypt '18.
(with Eik List and Mridul Nandi)

Turning Online Ciphers Off.
Transactions on Symmetric Cryptology 2017(2).
(with Elena Andreeva, Guy Barwell, Mridul Nandi, Dan Page and Martijn Stam)

Improved Security for OCB3.
Asiacrypt '17.
(with Mridul Nandi)

The Iterated Random Function Problem.
Asiacrypt '17.
(with Nilanjan Datta, Avijit Dutta, Nicky Mouha and Mridul Nandi)

OleF: an Inverse-Free Online Cipher.
Transactions on Symmetric Cryptology 2016(2).
(with Mridul Nandi)

An Inverse-Free Single-Keyed Tweakable Enciphering Scheme.
Asiacrypt '15.
(with Mridul Nandi)

Preprints

Universal Context Commitment without Ciphertext Expansion.
(with Arghya Bhattacharjee and Chandranan Dhar)

BBB PRP Security of the Lai-Massey Mode.
(with Mohammad Amin Raeisi)

Indifferentiability of 6-round Feistel.
(with Mridul Nandi, Sayantan Paul and Abishanka Saha)