论文标题
Rezone：减少T恤特权解除信任区
ReZone: Disarming TrustZone with TEE Privilege Reduction
论文作者
论文摘要
在Trustzone辅助的T台中，受信任的OS无限制地访问了安全和正常的世界记忆。不幸的是，这种建筑限制为攻击者开辟了一个探索过道，这些过道证明了如何利用一系列漏洞来劫持受信任的操作系统并对系统的完全控制，针对（i）丰富的执行环境（REE），（ii）所有受信任的应用程序（TAS）（TAS）和（iii）。在本文中，我们提出了Rezone。 Rezone Design的主要新颖性依赖于利用在商业上现成（COTS）平台上可用的Trustzone-Agnostic硬件原始原始图，以限制受信任的操作系统的特权。使用Rezone，将一个单片T恤进行了重组，并将其划分为名为“区域”的多个沙箱域，这些域仅访问私人资源。我们已经为I.MX 8Mquad EVK实施了重新划分，并将其与Android OS和Op-Tee集成在一起。我们使用Microbenchs和现实世界应用进行了广泛评估的Rezone。 Rezone可以维持流行的应用程序，例如由DRM保护的视频编码和可接受的性能开销。我们已经调查了80个CVE脆弱性报告，并估计Rezone可以减轻其中86.84％的速度。
In TrustZone-assisted TEEs, the trusted OS has unrestricted access to both secure and normal world memory. Unfortunately, this architectural limitation has opened an aisle of exploration for attackers, which have demonstrated how to leverage a chain of exploits to hijack the trusted OS and gain full control of the system, targeting (i) the rich execution environment (REE), (ii) all trusted applications (TAs), and (iii) the secure monitor. In this paper, we propose ReZone. The main novelty behind ReZone design relies on leveraging TrustZone-agnostic hardware primitives available on commercially off-the-shelf (COTS) platforms to restrict the privileges of the trusted OS. With ReZone, a monolithic TEE is restructured and partitioned into multiple sandboxed domains named zones, which have only access to private resources. We have fully implemented ReZone for the i.MX 8MQuad EVK and integrated it with Android OS and OP-TEE. We extensively evaluated ReZone using microbenchmarks and real-world applications. ReZone can sustain popular applications like DRM-protected video encoding with acceptable performance overheads. We have surveyed 80 CVE vulnerability reports and estimate that ReZone could mitigate 86.84% of them.
