MILP Based Differential Attack on Round Reduced WARP

Manoj Kumar; Tarun Yadav

Paper 2020/1598

MILP Based Differential Attack on Round Reduced WARP

Manoj Kumar and Tarun Yadav

Abstract

WARP is proposed by S. Banik et al. in SAC 2020. It is a 128-bit lightweight block cipher with 128-bit key. WARP is based on the 32-nibble type-2 Generalised Feistel Network (GFN) structure. It uses a permutation over nibbles which is designed to optimize the security and efficiency. The designers have provided a lower bound for the number of differentially active S-boxes but the detailed differential characteristics are not provided. In this paper, we discuss the MILP based search technique and present the differential characteristics for the 18-round and 19-round WARP with probability of 2^(-122) and 2^(-132) respectively. We also present a key recovery attack on the 21-round WARP with data complexity of 2^(113 )chosen plaintexts. To the best of our knowledge, these detailed differential characteristics are presented for the first time and this is the first key recovery attack on the 21-round WARP.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Preprint. MINOR revision.
Keywords: Lightweight Cryptography Block Cipher Differential Cryptanalysis MILP
Contact author(s): manojkumar @ sag drdo in
tarunyadav @ sag drdo in
History: 2021-08-02: revised; 2020-12-24: received; See all versions
Short URL: https://ia.cr/2020/1598
License: CC BY

BibTeX

@misc{cryptoeprint:2020/1598,
      author = {Manoj Kumar and Tarun Yadav},
      title = {{MILP} Based Differential Attack on Round Reduced {WARP}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2020/1598},
      year = {2020},
      url = {https://eprint.iacr.org/2020/1598}
}