Journal of South China University of Technology (Natural Science Edition) ›› 2010, Vol. 38 ›› Issue (5): 86-89.doi: 10.3969/j.issn.1000-565X.2010.05.017

• Computer Science & Technology • Previous Articles     Next Articles

Break of the C*- Scheme Symmetry Caused by Projection

Yuan Feng1  Hu Yu-pu Ou Hai-wen2  Zhao Dong1   

  1. 1.Key Laboratory of Computer Networks and Information Security,Ministry of Education,Xidian University,Xi'an 710071,Shaanxi,China;2.Key Laboratory of Information Security,Beijing Electronic Science and Technology Institute,Beijing 100070,China
  • Received:2009-05-31 Revised:2009-11-18 Online:2010-05-25 Published:2010-05-25
  • Contact: 袁峰(1982-),男,博士生,主要从事公钥密码学研究. E-mail:fyuan1234@yahoo.cn.
  • About author:袁峰(1982-),男,博士生,主要从事公钥密码学研究.
  • Supported by:

    国家“973”计划项目(2007CB311201); 国家自然科学基金资助项目(60970119 60803149)

Abstract:

The SFLASH cryptographic scheme is a C*-scheme with specific parameters.It has been broken by Dubois et al with differential cryptanalytic attacks.This paper reviews the basic attacks to the SFLASH scheme,and points out that a successful attack mainly depends on the symmetry of the SFLASH scheme.Moreover,the symmetry of the C*-scheme is investigated,and the fact that projection can break the symmetry of the C*-scheme is also strictly proved.The results indicate that the SFLASH scheme with projection can effectively withstand diffe-rential attacks.

Key words: cryptography, public key cryptography, polynomials, mapping, multivariate, symmetry, projection, C*-scheme