基于广义串空间模型构造攻击的缺陷及改进

Flaws and Improvement on Constructing Attack Based on Generalized Strand Space Model

该文设计一个类似于Millen曾经构造的“ffgg”协议——“ffgg^★”协议，它们有共同的密码学性质。使用基于广义串空间模型的构造攻击对该协议进行分析，结果表明协议在非类型缺陷攻击下是安全的，这与Millen用Pulson的归纳法分析“ffgg”协议有相同的结果，并指出该方法是有缺陷的。针对这个缺陷，给出改进的措施，改进的构造攻击能发现“ffgg^★”协议中的类型缺陷攻击。

This paper designs ＂ffgg^★＂ protocol which is similar to ＂ffgg＂ protocol constructed by Millen.They have cryptographic properties in commen. Then,the protocol is analyzed by using constructing attack based on generalized strand space model ,and it is proved that the protocol is secure under non-type-flaw attacks .After ＂ffgg＂ protocol is analyzed by Millen using Pulsons inductive approach,it is secure under non-type-flaw attacks,either. It is indicated that constructing attack has limitation. Finally, some improved measures are put forward,and type-flaw attack is found by using amendatory constructing attack in ＂ffgg^★＂ protocol.