On selection of optimal parameters for the WG stream cipher family

In this paper, we first present some new results about the Welch-Gong (WG) transformations, followed by a description of the WG stream cipher family which is built upon an LFSR and a WG transformation over an extension field. The randomness properties of keystreams produced by a decimated WG cipher are derived based on the new results. We also discuss the selection criteria for choosing the optimal parameters for a WG cipher in order to achieve the maximum level of security. Finally, we present the optimal parameters for the WG transformations over F2m, 7 ≤ m ≤ 16 based on the proposed criteria.

[1]  Adi Shamir,et al.  Cube Attacks on Tweakable Black Box Polynomials , 2009, IACR Cryptol. ePrint Arch..

[2]  Solomon W. Golomb,et al.  Binary Pseudorandom Sequences of Period 2n-1 with Ideal Autocorrelation , 1998, IEEE Trans. Inf. Theory.

[3]  Willi Meier,et al.  Fast correlation attacks on certain stream ciphers , 1989, Journal of Cryptology.

[4]  Thomas Siegenthaler,et al.  Correlation-immunity of nonlinear combining functions for cryptographic applications , 1984, IEEE Trans. Inf. Theory.

[5]  Alex Biryukov,et al.  Cryptanalytic Time/Memory/Data Tradeoffs for Stream Ciphers , 2000, ASIACRYPT.

[6]  Guang Gong,et al.  WG: A family of stream ciphers with designed randomness properties , 2008, Inf. Sci..

[7]  Ron Steinfeld,et al.  Cryptanalysis of WG-7: a lightweight stream cipher , 2012, Cryptography and Communications.

[8]  Guang Gong,et al.  Optimal parameters for the WG stream cipher family , 2013, 2013 13th Canadian Workshop on Information Theory.

[9]  Bart Preneel,et al.  Chosen IV Attack on Stream Cipher WG , 2005 .

[10]  James L. Massey,et al.  Shift-register synthesis and BCH decoding , 1969, IEEE Trans. Inf. Theory.

[11]  Hans Dobbertin,et al.  New cyclic difference sets with Singer parameters , 2004, Finite Fields Their Appl..

[12]  Guang Gong,et al.  WG-8: A Lightweight Stream Cipher for Resource-Constrained Smart Devices , 2015, EAI Endorsed Trans. Security Safety.

[13]  Amr M. Youssef,et al.  Cryptographic properties of the Welch-Gong transformation sequence generators , 2002, IEEE Trans. Inf. Theory.

[14]  Tor Helleseth,et al.  Fast Discrete Fourier Spectra Attacks on Stream Ciphers , 2011, IEEE Transactions on Information Theory.