STARSS: Small: Defending Against Hardware Covert Timing Channels

保护存储在计算机系统中的敏感用户信息是一个快速增长的问题，特别是当计算机从国防到移动的电话被普遍使用时。恶意黑客已经找到了肆无忌惮的方法来窃取敏感信息，主要是通过利用现有硬件和软件中的漏洞。在众多的信息泄漏形式中，隐蔽时间通道利用系统资源的访问时间，将秘密从具有较高安全证书的特洛伊进程泄漏到具有较低证书的间谍进程。这种隐蔽的定时通道是难以捉摸的，因为它们通过定时调制间接通信，而不会在存储器中留下任何物理痕迹。通过检测隐蔽定时通道的存在并对其进行防御，我们的项目通过防止不必要的敏感数据泄漏给恶意方，为社会带来了重大利益。该项目的三个主要目标是：1。研究硬件隐蔽定时通道的构建和操作背后的科学，2。设计机制来检测硬件定时通道，3。安装成本效益高的运行时防御策略，以破坏隐蔽定时通道的可靠性。我们研究科学的方法来确定关键的指示事件，并分析其在操作中的作用隐蔽的时间通道。我们设计的机制来捕捉运行时系统的行为，并检测一个隐蔽的定时通道的存在。最后，为了防止信息泄漏，我们使用分层，多级防御策略，我们估计对手的敏捷性，通过测量防御？的有效性，并自动重新校准我们的防御，以减少定时通道活动。

Safeguarding sensitive user information stored in computer systems is a fast growing concern, especially as computers are universally used everywhere from national defense to mobile phones. Malicious hackers have found unscrupulous ways to steal sensitive information largely by exploiting the vulnerabilities in existing hardware and software. Among the many forms of information leakage, covert timing channels exfiltrate secrets from a trojan process with higher security credentials to a spy process with lesser credentials by exploiting the access timing of system resources. Such covert timing channels are elusive since they communicate indirectly through timing modulation without leaving any physical trace in memory. By detecting the presence of covert timing channels and defending against them, our project offers significant benefits to society through preventing undesired sensitive data leakage to malicious parties. The three central objectives of this project are to: 1. Investigate the science behind the construction and operation of hardware covert timing channels, 2. Devise mechanisms to detect hardware timing channels, 3. Mount cost-effective, runtime defense strategies to undermine the reliability of covert timing channels. We investigate scientific ways to identify key indicator events, and analyze their roles in the operation of covert timing channels. We design mechanisms to capture the runtime system behavior, and detect the presence of a covert timing channel. Finally, to prevent information leakage, we use hierarchical, multi-level defense strategy where we estimate the agility of the adversary by measuring the defense?s effectiveness after deployment, and automatically recalibrate our defense to decimate the timing channel activity.