Abstract: Usage control (UCON) model enhances traditional access control models by continuous protection of object access. The researches on usage control enforcement mechanism leverage trusted computing techniques to ensure that the enforcement of policy is trusted. But these researches have problems that they lack the support of decision continuity. This paper proposes a novel architecture of trusted usage control system, which supports decision continuity by monitoring system changes continuously and controlling object resources during usage period. This paper also proposes a behavior attestation method to measure the dynamic behavior of usage control system on purpose of ensuring the trustworthy of policy enforcement by leveraging TCM (trusted cryptography module). Finally, this paper builds a system in operation system kernel to control the usage of files. The evaluation shows that the proposed model is feasible to support continuity of access decision evaluation and detect violation.

Key words: trusted computing, usage control, decision continuity, remote attestation

摘要： 针对访问的持续性保护问题，使用控制模型可以加强对传统模型的访问控制。已有的使用控制系统研究中，利用可信计算技术保证访问控制策略的正确实施。该类工作存在的问题是，对使用控制模型的决策连续特性支持不足。提出了新型的可信使用控制架构，持续监控系统变化，在使用过程中控制客体资源，有效支持决策连续性。提出了一种基于模型的行为证明方案，利用可信芯片TCM（trusted cryptography module）作为信任根，度量使用控制架构的动态行为，确保策略有效实施，并在操作系统内核中实现了该可信使用控制架构。通过实验评估，使用控制系统支持决策连续性并能及时发现攻击行为，是一种有效的可信使用控制的解决方案。

关键词: 可信计算, 使用控制, 决策持续性, 远程证明