Abstract
HyRAL is a blockcipher whose block size is 128 bits, and it supports the key lengths of 128, 129, …,256 bits. The cipher was proposed for the CRYPTREC project, and previous analyses did not identify any security weaknesses. In this paper, we consider the longest key version, 256-bit key HyRAL, and present the analysis in terms of equivalent keys. First, we show that there are 251.0 equivalent keys (or 250.0 pairs of equivalent keys). Next, we propose an algorithm that derives an instance of equivalent keys with the expected time complexity of 248.8 encryptions and a limited amount of memory. Finally, we implement the proposed algorithm and fully verify its correctness by showing several instances of equivalent keys.
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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)
Biham, E., Shamir, A.: Differential Cryptanalysis of DES-like Cryptosystems. J. Cryptology 4(1), 3–72 (1991)
Cryptography Research and Evaluation Committees (CRYPTREC), http://www.cryptrec.go.jp/english/index.html
Cryptography Research and Evaluation Committees (CRYPTREC): CRYPTREC Report, Report of the Scheme Committee (2010) (in Japanese), http://www.cryptrec.go.jp/english/report.html
Daemen, J., Knudsen, L.R., Rijmen, V.: The Block Cipher SQUARE. In: Biham, E. (ed.) FSE 1997. LNCS, vol. 1267, pp. 149–165. Springer, Heidelberg (1997)
Hirata, K.: Submission Documents of HyRAL to the CRYPTREC Project (2010), http://www.cryptrec.go.jp/english/topics/cryptrec_20101001_callforattack.html
Hirata, K.: The 128bit Block Cipher HyRAL (Hybrid Randomization Algorithm): Common Key Block Cipher. In: Proceedings of the 2010 International Symposium on Intelligence Information Processing and Trusted Computing, IPTC 2010, pp. 9–14. IEEE Computer Society, Washington, DC (2010), http://dx.doi.org/10.1109/IPTC.2010.179
Hirata, K.: The 128bit Blockcipher HyRAL. In: The 2010 Symposium on Cryptography and Information Security, 1D1-1, SCIS 2010 (2010) (in Japanese)
Igarashi, Y., Takagi, Y., Kaneko, T.: Security Evaluation of HyRAL against Linear Cryptanalysis. In: The 2010 Symposium on Cryptography and Information Security, 1D1-3, SCIS 2010 (2010) (in Japanese)
Inoue, T., Kaneko, T.: Security Evaluation of HyRAL against Boomerang Attack. IEICE Tech. Rep. 111(142), 1–6 (2011) (in Japanese); IT 2011-07-14
Iwata, T.: Security Evaluation Report of HyRAL. In: Technical Report of CRYPTREC, Investigation Reports Related to Cryptographic Techniques in FY 2010 (2011) (in Japanese)
Knudsen, L.R.: Cryptanalysis of LOKI. In: Matsumoto, T., Imai, H., Rivest, R.L. (eds.) ASIACRYPT 1991. LNCS, vol. 739, pp. 22–35. Springer, Heidelberg (1993)
Knudsen, L.R.: Truncated and Higher Order Differentials. In: Preneel, B. (ed.) FSE 1994. LNCS, vol. 1008, pp. 196–211. Springer, Heidelberg (1995)
Lai, X.: Higher Order Derivatives and Differential Cryptanalysis. In: Blahut, R.E., Massey, J.L. (eds.) Communications and Cryptography: Two Sides of One Tapestry, pp. 227–233. Kluwer Academic Publishers, Norwell (1994)
Matsui, M.: Linear Cryptanalysis Method for DES Cipher. In: Helleseth, T. (ed.) EUROCRYPT 1993. LNCS, vol. 765, pp. 386–397. Springer, Heidelberg (1994)
Matsui, M.: The First Experimental Cryptanalysis of the Data Encryption Standard. In: Desmedt, Y.G. (ed.) CRYPTO 1994. LNCS, vol. 839, pp. 1–11. Springer, Heidelberg (1994)
Shibayama, N., Igarashi, Y., Kaneko, T., Hangai, S.: Impossible Differential Attack on HyRAL. In: Forum on Information Technology, L-022 (2010) (in Japanese)
Shibayama, N., Igarashi, Y., Kaneko, T., Hangai, S.: On Impossible Differential of HyRAL Using MDS Characteristic. In: The 2010 IEICE Engineering Sciences Society Conference, A-7-8 (2010) (in Japanese)
Shibayama, N., Igarashi, Y., Kaneko, T., Hangai, S.: Security Evaluation of HyRAL against Saturation Cryptanalysis. In: The 33rd Symposium on Information Theory and its Applications, SITA 2010, 10.1 (2010) (in Japanese)
Shibayama, N., Igarashi, Y., Kaneko, T., Hangai, S.: Higher Order Differential Attack on HyRAL. IEICE Tech. Rep. 110(443), 341–347 (2011) (in Japanese); ISEC 2010-123
Shibayama, N., Igarashi, Y., Kaneko, T., Hangai, S.: Security Evaluation of HyRAL against Saturation Cryptanalysis (II). IEICE Tech. Rep. 111(123), 103–109 (2011) (in Japanese); ISEC 2011-19
Shibayama, N., Kaneko, T., Hangai, S.: New Saturation Characteristics of HyRAL. IEICE Tech. Rep. 111(455), 53–60 (2012) (in Japanese); ISEC 2011-81
Taga, B., Tanaka, H.: Higher Order Differential Characteristics of HyRAL. In: The 2011 Symposium on Cryptography and Information Security, 2B2-2, SCIS 2011 (2011) (in Japanese)
Takagi, Y., Igarashi, Y., Kaneko, T.: Security Evaluation of HyRAL against Differential Attack. In: The 2010 Symposium on Cryptography and Information Security, 1D1-2, SCIS 2010 (2010) (in Japanese)
Yamaguchi, Y., Shibayama, N., Kaneko, T.: Higher Order Differential Property of HyRAL (II). In: The 2012 Symposium on Cryptography and Information Security, 1C3-4, SCIS 2012 (2012) (in Japanese)
Yamaguchi, Y., Igarashi, Y., Kaneko, T.: Higher Order Differential Property of HyRAL. In: The 63rd Joint Conference of Electrical and Electronics Engineers in Kyushu, 02-1A-06 (2010) (in Japanese)
Youm, H.Y., Song, J.H., Lee, S.Y.: Security Analysis of HyRAL. In: Technical Report of CRYPTREC, Investigation Reports Related to Cryptographic Techniques in FY 2010 (2011)
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Asano, Y., Yanagihara, S., Iwata, T. (2012). Cryptanalysis of 256-Bit Key HyRAL via Equivalent Keys. In: Bao, F., Samarati, P., Zhou, J. (eds) Applied Cryptography and Network Security. ACNS 2012. Lecture Notes in Computer Science, vol 7341. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-31284-7_16
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DOI: https://doi.org/10.1007/978-3-642-31284-7_16
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