Quantum implementation of SLIM and its Grover cryptanalysis


ÇILDIROĞLU H. Ö., YAYLA O.

Physica Scripta, vol.100, no.10, 2025 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Volume: 100 Issue: 10
  • Publication Date: 2025
  • Doi Number: 10.1088/1402-4896/ae1336
  • Journal Name: Physica Scripta
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Compendex, INSPEC, zbMATH
  • Keywords: block ciphers, grover analysis, quantum implementation, SLIM
  • Middle East Technical University Affiliated: Yes

Abstract

We present a novel quantum implementation of SLIM, a lightweight 32/80-bit Feistel cipher. By inverting its Key addition-Substitution-Permutation (KSP) layers without ancillary qubits, we construct the full quantum circuit using 112 qubits with quantum cost 30,404 and depth 4,066. To assess quantum resilience, we implement Grover’s algorithm with three plaintext-ciphertext pairs (r = 3; 337 qubits), yielding an attack cost of 2111 under NIST’s MAXDEPTH constraints—below the Level-1 threshold 2170. While SLIM falls short of NIST’s security threshold for near-term quantum attacks, among other lightweight BCs, its efficient architecture retains practical advantages for constrained applications.