公钥密码基础设施在电信运营商的应用

随着密码法的实施,我国将信息系统密码应用提升到了法律层面,要求加强公钥基础设施在网络实体互通互信方面的应用。提出了一种采用严格层次结构建设统一电信公钥基础设施的方案,即建立一个全国电信运营商根CA作为信任锚,而各大电信运营商成为独立的子CA,形成“全国电信运营商根CA－电信运营商子CA”的证书信任链,提供PKI安全服务。该方案不仅可以实现电信运营商CA之间的互通互认,也有利于统一电信公钥基础设施成为全球范围信任的电子认证服务提供商,进而在国际证书标准制定上有更大的影响力和话语权。     

ARIA密码算法的不可能差分归一化分析

Unified Impossible Differential (UID) cryptanalysis is a systematic method for finding impossible differentials for block ciphers. Regarding to the problem of automatically retrieving the impossible differential characteristics of block ciphers, with the use of particular intermediate difference state expression, UID gets the same or better results compared with other present cryptanalysis results. ARIA is a Korean block cipher expecting that there are no impossible differentials on four or more rounds. Based on a property of the Diffusion Layer (DL) of ARIA, a specific selection is used before conflict searching to optimize. UID is applied to ARIA, and 6 721 impossible differential chains are found. The length of those chains is four rounds, the same as existing results, but more varied in form. Moreover, ARIA is a Substitution-Permutation Network (SPN), not a Feistel structure or generalized Feistel structure as UID was applied to before.