Fixslicing AES-like Ciphers

New Insights on AES-Like SPN Ciphers

It has been proved in Eurocrypt 2016 by Sun et al. that if the details of the S-boxes are not exploited, an impossible differential and a zero-correlation linear hull can extend over at most 4 rounds of the AES. This paper concentrates on distinguishing properties of AES-like SPN ciphers by investigating the details of both the underlying S-boxes and the MDS matrices, and illustrates some new i...

Analyzing Permutations for AES-like Ciphers: Understanding ShiftRows

Designing block ciphers and hash functions in a manner that resemble the AES in many aspects has been very popular since Rijndael was adopted as the Advanced Encryption Standard. However, in sharp contrast to the MixColumns operation, the security implications of the way the state is permuted by the operation resembling ShiftRows has never been studied in depth. Here, we provide the first struc...

On algebraic and statistical properties of AES-like ciphers

Looting the LUTs : FPGA Optimization of AES and AES-like Ciphers for Authenticated Encryption

In this paper, we investigate the efficiency of FPGA implementations of AES and AES-like ciphers, specially in the context of authenticated encryption. We consider the encryption/decryption and the authentication/verification structures of OCB-like modes (like OTR or SCT modes). Their main advantage is that they are fully parallelisable. While this feature has already been used to increase the ...

Cryptanalysis of Ciphers Based on AES Structure

AES is the best known and most widely used block cipher. Its three versions (AES-128, AES-192, and AES-256) differ in their key sizes (128 bits, 192 bits and 256 bits) and in their number of rounds (10, 12, and 14, respectively). Our present work investigates the recently reported attacks on AES 256 and AES 192. Instead of concentrating on the actual algorithms of these attacks we shall be more...