前向可修正属性算术验证的研究

Algorithmic Verification of Forward Correctability

目前验证前向可修正属性的"展开方法"是不完备的,即当"展开定理"的局部条件不满足时,不能判断出系统不满足前向可修正属性。为此,提出一种基于状态转换系统的前向可修正属性验证方法,该方法将前向可修正属性的验证归约为可达性问题,进而可借助可达性检测技术完成属性的验证。该方法是完备的,且当属性不成立时,可以给出使属性失效的反例,反例的给出对非法信息流的消除和控制具有直接的帮助。最后,通过磁臂隐通道的例子说明了方法的有效性和实用性。

Due to the incompleteness of the ＂Unwinding Theorem＂,a system can＇t be judged to fail to satisfy the forward correctability,when some local conditions of ＂Unwinding Theorem＂ are not satisfied.This paper proposed an algorithmic verification technique to check the forward correctability based on the state transition system.The technique reduces forward correctability checking to the reachability problem and the reduction enables us to use the reachability checking technique to perform forward correctability checking.Our method is complete and it can give a counter-examples to control and eliminate the illegal information flow when a system fails to satisfy the forward correctability.Finally,Disk-arm Convert Channel illustrates the effectiveness and practicality.