CT-ISG: Applications and Evolution of Trusted Platform Module Technology

可信平台模块（TPM）作为商用pc、移动设备和服务器中的标准组件的日益普及，为安全可扩展和分布式计算提供了令人兴奋的新可能性。该项目旨在通过研究TPM的新应用程序，并提出可以添加到TPM的未来版本中的新特性，从而推动未来TPM的发展，从而支持更广泛的有用应用程序。本项目首先探索当前一代TPM （TPM 1.2）可以实现哪些新应用程序，而不需要信任中央处理单元（CPU）、操作系统（OS）或硬件的其他组件。将所需的可信计算基础缩小到仅TPM本身可以提高安全性，并允许更多用户立即更轻松地从TPM中受益。正在研究的一个特殊思想是实现“虚拟单调计数器”，并反过来使用这些来启用许多应用程序，包括在不受信任的服务器上的安全虚拟存储，以及用于身份验证、访问或委托应用程序的一次性数字证书。在现有TPM的基础上，本项目提出内置TPM对“限数对象”的支持，可以有多种形式和应用，例如用于个人数字共享和权限管理的限数密钥，以及用于离线个人电子商务和贸易的限数令牌。最后，本项目提出并详细介绍了将TPM演变为可信执行模块（Trusted Execution Module， TEM）的过程。与TPM只能接受一小部分指令（主要用于加密操作）不同，TEM可以接受任意指令的加密数据包并对其进行计数限制。TEM支持许多新的应用程序，包括通用有限计数加密和具有脱机客户机的安全移动代理。

The increasing adoption of the Trusted Platform Module (TPM) as a standard component in commodity PCs, mobile devices, and servers, offers exciting new possibilities in secure scalable and distributed computing. This project aims to drive the evolution of future TPMs by investigating new applications of TPMs, and by proposing new features that can be added to future versions of the TPM to enable an even wider variety of useful applications. This project begins by exploring what new applications are possible with the current generation of TPM (TPM 1.2) -- without requiring that the Central Processing Unit (CPU), Operating System (OS), or other components of the hardware be trusted. Shrinking the required trusted computing base to only the TPM itself improves security, and allows more users to immediately and more easily benefit from TPMs. A particular idea being studied is that of implementing "virtual monotonic counters", and in turn using these to enable many applications, including secure virtual storage on untrusted servers, and one-time-use digital certificates for authentication, access, or delegation applications. Going beyond existing TPMs, this project proposes built-in TPM support for "count-limited objects", which can have many forms and applications, such as count-limited keys for personal digital sharing and permissions management, and count-limited tokens for offline personal electronic commerce and trade. Finally, this project proposes and details the evolution of the TPM into a Trusted Execution Module (TEM). Unlike a TPM which can only accept a small set of instructions (mainly for cryptographic operations), a TEM can accept and count-limit encrypted packets of arbitrary instructions. A TEM enables many new applications, including generalized count-limited cryptography, and secure mobile agents with offline clients.