Scholarlink

<p>The <Emphasis FontCategory="NonProportional">CRAFT</Emphasis> cipher is a lightweight tweakable block cipher introduced at FSE 2019. Its design aims to incorporate countermeasures against Differential Fault Attacks at the algorithmic level. The cipher employs a lightweight and involutory S-box along with a simple linear layer, enabling efficient encryption and decryption operations. In particular, <Emphasis FontCategory="NonProportional">CRAFT</Emphasis> utilizes a straightforward tweakey schedule that generates four 64-bit round tweakeys, which are reused throughout the encryption process. Despite its lightweight design, the resistance of <Emphasis FontCategory="NonProportional">CRAFT</Emphasis> against impossible differential analysis has not been thoroughly evaluated, with limited attention from cryptanalysts in this regard. Hence, this paper presents a comprehensive analysis of <Emphasis FontCategory="NonProportional">CRAFT</Emphasis> specifically targeting its resistance to impossible differential cryptanalysis. By employing an Satisfiability Modulo Theory (SMT) based automatic search tool, we successfully identify both 12-round related-tweak impossible differential distinguishers and 15-round related-tweakey impossible differential distinguishers for <Emphasis FontCategory="NonProportional">CRAFT</Emphasis>, marking the first discovery of such distinguishers for this cipher. Our results indicate that the tweak in <Emphasis FontCategory="NonProportional">CRAFT</Emphasis> enhances the cipher’s flexibility, provided it receives appropriate attention. In addition, we conduct key-recovery attacks on reduced-round <Emphasis FontCategory="NonProportional">CRAFT</Emphasis>, successfully recovering the 128-bit keys for 20-round, 21-round, and 23-round variants. Based on our comprehensive analysis and experimental results, we conclude that <Emphasis FontCategory="NonProportional">CRAFT</Emphasis> demonstrates effective resistance against impossible differential cryptanalysis.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Impossible differential cryptanalysis of lightweight tweakable block cipher CRAFT

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年12月17日

查看全文
  • Fen Liu,
  • Yongqiang Li,
  • Huiqin Chen,
  • Li Ma,
  • Zhengbin Liu,
  • Wenyin Yang

摘要

The CRAFT cipher is a lightweight tweakable block cipher introduced at FSE 2019. Its design aims to incorporate countermeasures against Differential Fault Attacks at the algorithmic level. The cipher employs a lightweight and involutory S-box along with a simple linear layer, enabling efficient encryption and decryption operations. In particular, CRAFT utilizes a straightforward tweakey schedule that generates four 64-bit round tweakeys, which are reused throughout the encryption process. Despite its lightweight design, the resistance of CRAFT against impossible differential analysis has not been thoroughly evaluated, with limited attention from cryptanalysts in this regard. Hence, this paper presents a comprehensive analysis of CRAFT specifically targeting its resistance to impossible differential cryptanalysis. By employing an Satisfiability Modulo Theory (SMT) based automatic search tool, we successfully identify both 12-round related-tweak impossible differential distinguishers and 15-round related-tweakey impossible differential distinguishers for CRAFT, marking the first discovery of such distinguishers for this cipher. Our results indicate that the tweak in CRAFT enhances the cipher’s flexibility, provided it receives appropriate attention. In addition, we conduct key-recovery attacks on reduced-round CRAFT, successfully recovering the 128-bit keys for 20-round, 21-round, and 23-round variants. Based on our comprehensive analysis and experimental results, we conclude that CRAFT demonstrates effective resistance against impossible differential cryptanalysis.