基于椭圆曲线密码体制的先应式秘密共享方案-《计算机技术与发展》

文章信息/Info

Title:: A Proactive Secret Sharing Scheme Based on the Elliptic Curve Cryptosystem

Author(s):: GAO Zhao-feng; YE Yan-feng; ZHUANG Yi; College of Info. Sqi. ＆ Techn. ,Nanjing Univ. of Aeronautics and Astronautics

Keywords:: proactive secret sharing; verifiable secret sharing （VSS）; shares refresh

摘要:: 直接使用传统密码学甚至门限密码学提供的方法都不能很好地保证密钥的安全性。而先应式秘密共享方案则能较好地解决这类问题。它是在（t，n）门限密码学密钥共享的基础上，通过周期性地刷新共享份额的值（但不改变共享的密钥）并清除原来的共享份额值，使得攻击者在一个周期中获得的信息在刷新之后变得毫无用处。所以，攻击者要想窃取一个系统的密钥，必须在同一个周期内攻破t个或者t个以上的服务器才可能成功。因此，合理设置门限参数t和时间周期的长短就可以保证密钥的长期安全性。文中设计了一种基于椭圆曲线密码体制的先应式秘密共享方案，包

Abstract:: It＇s insufficient just to apply the classic cryptography as well as threshold cryptosysterns. Only proactive secret sharing can properly protect it. Proactive secret sharing is a non - trivial extension of （ t, n ） threshold cryptosystems, where shares are periodically renewed （without changing the secret ） in such a way that information gained by the adversary in one time period is useless for attacking the secret after the shares are renewed. Hence, the adversary willing to learn the secret needs to break to all t share holders or more than t share holders during the same time period. If the time period and the threshold t are selected properly, proactive secret sharing can maintain the overall security of the information. The article presents a proactive secret sharing scheme based on the Elliptic Curve Cryptcsystem（ECC）, including initialization of share,renewal of share,recovery of share and reconstruction of secret. The paper implements all algorithms of proactive secret sharing protocol