Realizing Full-System Dynamic Information Flow Tracking via Relaxed Static Stability

信息流是计算机安全中的一个核心概念，但在运行的系统中标记信息并以准确的方式跟踪信息如何在整个系统中流动仍然是一个悬而未决的问题。 我们正在发展控制论、信息论和系统中的基本概念，以使用我们所谓的松弛静态稳定性方法来解决这个问题。在一个运行的系统中，当信息被用户剪切和粘贴或处理时，它以意想不到的方式流动。 两个主要挑战是地址依赖性和控制依赖性。 过度标记这些依赖关系会导致整个系统迅速被标记，而标记不足则意味着重要的信息流不会被跟踪。 现代战斗机和隐形飞机的设计没有固有的稳定性，然后将先进的数字“电传操纵”系统纳入设计中，以创建一个可以实际飞行的稳定系统。 通过应用这种相同的“放松静态稳定性”方法，我们正在设计一个准确的动态信息流跟踪系统，在过度标记和欠标记之间进行正确的权衡。 这将实现基于动态信息流跟踪的全新应用类别，从数字取证和恶意软件分析到数据来源。 通过解决安全和隐私研究的基本需求，我们希望我们的工作在任何领域都有影响，其中计算机中的信息流是重要的理解。

Information flow is a central concept in computer security, yet it is still an open problem to tag information in a running system and track how the information flows throughout the system in an accurate manner. We are developing the fundamental concepts in control theory, information theory, and systems to solve this problem using what we call a relaxed static stability approach.In a running system, as information is cut-and-pasted by users or processed, it flows in unexpected ways. Two major challenges are address dependencies and control dependencies. Overtagging these dependencies causes the entire system to quickly become tagged, while undertagging them means that important flows of information are not tracked. Modern fighter jets and stealth aircraft are designed without inherent stability, then advanced digital "fly-by-wire" systems are incorporated into the design to create a stable system that can actually fly. By applying this same kind of "relaxed static stability" approach, we are designing an accurate dynamic information flow tracking system that makes the right tradeoffs between overtagging and undertagging. This will enable whole new classes of applications based on dynamic information flow tracking, ranging from digital forensics and malware analysis to data provenance. By addressing a fundamental need in security and privacy research, we expect our work to have impact in any field where the flow of information in a computer is important to understand.