CLEFIA

About: CLEFIA is a research topic. Over the lifetime, 124 publications have been published within this topic receiving 3350 citations.

A Very Compact Architecture of CLEFIA Block Cipher for Secure IoT Systems

Abstract: In this paper, a very compact architecture of the CLEFIA block cipher is presented. This architecture has a 128-bit plaintext/ciphertext and a 128-bit key and processes the data using a 4-bit datapath and therefore requires only a small number of hardware resources. The target of this architecture is ultra-low area devices for Internet of Things systems. The design was coded using the Verilog language and the BASYS3 board (Artix 7 XC7A35T) was used for the hardware implementation. The proposed implementation utilizes only 606 FPGA LUTs and 477 FFs and reaches a data throughput of 28 Mbps at 115 MHz clock frequency.

A white-box CLEFIA implementation for mobile devices

Abstract: A difficult problem in mobile internet security is how to prevent key leakage when using traditional symmetric cryptographic algorithms in mobile devices, because mobile devices face with White-Box attacking environment so the cryptographic program running on mobile devices can be fully controlled by attackers. In the other hand, the memory space in mobile devices is relatively limited compared with most computers, so an anti-key-leakage tiny cryptographic algorithms is needed for mobile devices which have relatively high degree of security and high efficiency meanwhile. This paper puts forward two White-Box CLEFIA implementations according to the special structure of CLEFIA. Compared with Chow's White-Box AES, one of the methods can minimize the size of memory space occupied and improve the calculation efficiency by adding random numbers into each step of CLEFIA. And the other method put forward a new structure of lookup table by increasing its dimension. At last, an efficiency test and some simple security comments are proposed.

Protecting Last Four Rounds of CLEFIA is Not Enough Against Differential Fault Analysis.

Abstract: In this paper we propose a new differential fault analysis (DFA) on CLEFIA of 128-bit key. The proposed attack requires to induce byte faults at the fourteenth round of CLEFIA encryption. The attack uses only two pairs of fault-free and faulty ciphertexts and uniquely determines the 128-bit secret key. The attacker does not need to know the plaintext. The most efficient reported fault attack on CLEFIA, needs fault induction at the fifteenth round of encryption and can be performed with two pairs of fault-free and faulty ciphertexts and brute-force search of around 20 bits. Therefore, the proposed attack can evade the countermeasures against the existing DFAs which only protect the last four rounds of encryption. Extensive simulation results have been presented to validate the proposed attack. The simulation results show that the attack can retrieve the 128-bit secret key in around one minute of execution time. To the best of authors’ knowledge the proposed attack is the most efficient attack in terms of both the input requirements as well as the complexity.