基于信息流模型的TCB完整性策略分析方法与工具

基于信息流模型的TCB完整性策略分析方法与工具 Policy Analysis Methods and Tools of Information Flow Model Based on TCB Integrity 胡伟 HU Wei 1 first-author 姬东耀 JI Dongyao 1 中国科学院信息工程研究所信息安全国家重点实验室 中国科学院信息工程研究所信息安全国家重点实验室 State Key Laboratory of Information Security,Institute of Information Engineering,Chinese Academy of Sciences State Key Laboratory of Information Security,Institute of Information Engineering,Chinese Academy of Sciences TCB（trusted computing base）完整性保护对于计算机系统安全具有十分重要的意义,目前的静态度量方法并不完善,而动态度量方法还很不成熟,因而提出一种基于策略的分析方法来分析系统TCB和域TCB的完整性.这一方法将系统策略文件中的描述解析成信息流形式,然后再将其抽象为有向图形式,最后利用图论中的方法分析信息流情况,给出完整性破坏的信息流传播路径.此方法的思想可以用在任何通过执行某些操作会产生信息流的环境中.根据这一方法,开发了一个原型工具,并以SELinux操作系统为例进行了实验分析.实验表明它能分析策略中的信息流向,并能实时给出策略违反图.此方法和工具可以作为现有完整性度量方法的有效补充. TCB integrity protection is of great significance.The static measurement method is not perfect,and the dynamic measurement method is still immature,so a policy-based method to analyze the integrity of the system TCB and domain TCB is proposed.This method parses the system policy file into the form of information flow,and then abstracts it out into the form of directed graph.At last the information flow of the graph is analyzed using graph theory,and the information flow propagation path of the integrity violation is given.The idea of this method can be used in any situations where performed operations will produce information flow.Based on this method,aprototype tool is developed.In the experiment,the integrity of TCB in the SELinux operation system is studied.The experiment indicates that the tool can analyze the information flow of the policy file,and give the policy violation graph in real time.This method and tool can be an effective complement of existing integrity measurement methods. 信息流 完整性 类型强制模型 可信计算基 策略违反图 information flow integrity type enforcement（TE）model trusted computing base（TCB） policy violation graph 10.14188/j.1671-8836.2013.05.017 TP309 国家自然科学基金资助项目（90604010）;中国科学院战略性先导专项（xda06010702） 2013-05-01 2021-04-01 5 59