Proposition of Two Cipher Structures
In this paper, we have proposed two block cipher structures which can be considered as variants of SP-network and Generalized Feistel structure respectively. Our main idea is to improve the diffusion effect when mixing all the sub-blocks together in each round. We also show that compared with the original structures, our structures have several important advantages. Then we evaluate the security of our structures against main attacks by estimating the upper bounds for differential and linear probabilities, and also the maximum number of rounds for impossible differential. In the end, we present two example ciphers which are based on the structures proposed, and we also adopt several novel and state-of-the-art design techniques. Then by explaining the design rationales and evaluating the security of the example ciphers under main attack settings, we can conclude that both of our ciphers can achieve enough immunity against known attacks and also have high performances.
KeywordsBlock Cipher cipher structure differential probability linear probability provable security impossible differential characteristic
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- 1.Data Encryption Standard (DES). Federal Information Processing Standards Publication FIPS-46-3. National Bureau of Standards (1999)Google Scholar
- 4.Knudsen, L.R.: DEAL - A 128-bit Block Cipher. Technical Report 151, Department of Informatics, University of Bergen, Bergen, Norway (1998)Google Scholar
- 8.Biryukov, A., Khovratovich, D.: Related-Key Cryptanalysis of the Full AES-192 and AES-256. In: ASIACRYPT 2009, vol. LNCS (2009) (to appear)Google Scholar
- 9.Biham, E., Shamir, A.: Differential Cryptanalysis of DES-like Cryptosystem (Extended Abstract). In: Menezes, A., Vanstone, S.A. (eds.) CRYPTO 1990. LNCS, vol. 537, pp. 2–21. Springer, Heidelberg (1991)Google Scholar
- 10.Matsui, M.: Linear Cryptanalysis Method for DES Cipher. In: Helleseth, T. (ed.) EUROCRYPT 1993. LNCS, vol. 765, pp. 386–397. Springer, Heidelberg (1994)Google Scholar
- 11.Biham, E., Biryukov, A., Shamir, A.: Cryptanalysis of Skipjack Reduced to 31 Rounds Using Impossible Differentials. In: Stern, J. (ed.) EUROCRYPT 1999. LNCS, vol. 1592, pp. 12–23. Springer, Heidelberg (1999)Google Scholar
- 12.Nyberg, K., Kundsen, L.R.: Provable Security Against Differential Cryptanalysis. In: Brickell, E.F. (ed.) CRYPTO 1992. LNCS, vol. 740, pp. 566–574. Springer, Heidelberg (1993)Google Scholar