SaTC: An Architecture for Restoring Trust in Our Personal Computing Systems

今天的计算机是如此复杂和不透明，用户不可能希望知道，更不用说信任，发生在机器内的一切。虽然软件安全技术有助于确保用户计算的完整性，但它们仅与底层硬件一样值得信赖。尽管许多提案为硬件信任问题提供了一些缓解，但用户最终必须依赖其他方的保证。这项工作通过一个简单、小而慢的可插拔硬件元素来恢复硬件信任。本项目研究的技术提供了一个核心的信任，保持即使是最积极的系统在线路上，而不会减慢他们，很容易恢复。对于这个缓慢，但值得信赖的硬件元素是有用的在真实的世界的系统，它不能显着降低系统性能。为了实现这一目标，这项工作开发了两个互补的技术：执行指令的依赖性自由并行验证，和加密的基于哈希的内存完整性保证。此外，加密散列还确保代码完整性，并防止处理器执行自己的恶意代码。这些技术的组合提供了一个安全的硬件环境，只要他们的软件也是安全的，用户就不必担心他们的数据被泄露。因此，当与成熟的软件安全技术相结合时，这项工作可以显著提高用户对其计算系统的信任程度。

Computers today are so complex and opaque that a user cannot possibly hope to know, let alone trust, everything occurring within the machine. While software security techniques help ensure the integrity of user computations, they are only as trustworthy as the underlying hardware. Even though many proposals provide some relief to the problem of hardware trust, the user must ultimately rely on the assurances of other parties. This work restores hardware trust through a simple, small, and slow pluggable hardware element. This project investigates techniques that provides a kernel of trust that keeps even the most aggressive systems in line without slowing them down and is easy to manufacture.For this slow but trusted hardware element to be useful in real world systems, it must not degrade system performance significantly. To achieve this goal, this work develops two complimentary techniques: dependence-free parallel verification of executed instructions, and cryptographic hash-based memory integrity assurance. Additionally, cryptographic hashing also ensures code integrity and prevents the processor from executing its own malicious code. A combination of these techniques provides a secure hardware environment where users need not worry about their data being compromises, as long as their software is also secure. Therefore, when combined with well-developed software security techniques, this work provides a significant increase in the level of trust users place in their computing systems.