一般化通用可组合安全框架研究

Research on generalized universally composable security framework

分析一般化通用可组合安全框架(GUC框架)解决的关键问题及其机理。在此基础上深入研究实现GUC承诺的一个协议示例,得出GUC框架虽然要求仿真器与现实敌手共用同一个全局可信建立,但是二者对于该全局可信建立的利用程度是不同的。将GUC框架与UC框架及其改进版本进行比较,发现能实现包括安全计算在内的所有良好形式的理想功能的现有框架拥有一个共性,即仿真器的能力比现实敌手的能力强。讨论了GUC框架仍然存在的不足。

A note on generalized universal composability is given. Firstly, key problems resolved by GUC framework and how they are resolved are analyzed. On the basis of this, a protocol instance is researched in depth, which GUC-realizes commit- ment ideal functionality, and it is showed that GUC framework requires the simulator to use the same ideal functionality of global setup as the real adversary, but the value in use of the global setup are very different to them. Secondly, GUC frame- work, UC framework and its modification editions are compared, and it is found that the simulator is more powerful than the real adversary in all existing frameworks which enable universally composable secure computation. Finally, shortcomings in GUC framework are discussed.