TitanCFI：在可信根中强制执行控制流完整性
TitanCFI: Toward Enforcing Control-Flow Integrity in the Root-of-Trust
AI总结：
本文提出TitanCFI，一种在现代RISC-V SoC的可信根中强制执行控制流完整性的新方法，通过修改内核提交阶段将控制流指令流式传输至RoT固件执行策略，复用硬件资源并利用防篡改存储保护元数据，实现1%的极低面积开销。
摘要：
现代RISC-V平台控制和监控安全关键系统，如工业控制器和自动驾驶车辆。尽管这些平台具有可信根（RoT）来存储认证密钥并启用安全启动技术，但它们通常缺乏控制流完整性（CFI）的强制执行，并且容易受到网络攻击，这些攻击会转移应用程序的控制流以触发恶意行为。最近在RISC-V系统中强制执行CFI的技术包括ISA修改或定制硬件IP，所有这些都需要专门的二进制工具链或在硬件中设计CFI原语。本文提出了TitanCFI，一种在RoT中强制执行CFI的新方法。TitanCFI修改受保护内核的提交阶段，以将控制流指令流式传输到RoT，并将CFI强制执行策略集成到RoT固件中。我们的方法实现了片上系统（SoC）中硬件资源的最大程度复用，避免了定制IP的设计和编译工具链的修改，同时利用RoT的防篡改存储和加密加速器来保护CFI元数据。我们在现代RISC-V SoC上实现了所提出的架构以及RoT中的返回地址保护策略，并对面积和运行时开销进行了基准测试。实验结果表明，对于大多数基准测试，TitanCFI实现了与现有技术（SoA）硬件CFI解决方案相当的开销，且面积开销更低，仅导致1%的额外面积占用。
英文摘要：
Modern RISC-V platforms control and monitor security-critical systems such as industrial controllers and autonomous vehicles. While these platforms feature a Root-of-Trust (RoT) to store authentication secrets and enable secure boot technologies, they often lack Control-Flow Integrity (CFI) enforcement and are vulnerable to cyber-attacks which divert the control flow of an application to trigger malicious behaviours. Recent techniques to enforce CFI in RISC-V systems include ISA modifications or custom hardware IPs, all requiring ad-hoc binary toolchains or design of CFI primitives in hardware. This paper proposes TitanCFI, a novel approach to enforce CFI in the RoT. TitanCFI modifies the commit stage of the protected core to stream control flow instructions to the RoT and it integrates the CFI enforcement policy in the RoT firmware. Our approach enables maximum reuse of the hardware resource present in the System-on-Chip (SoC), and it avoids the design of custom IPs and the modification of the compilation toolchain, while exploiting the RoT tamper-proof storage and cryptographic accelerators to secure CFI metadata. We implemented the proposed architecture on a modern RISC-V SoC along with a return address protection policy in the RoT, and benchmarked area and runtime overhead. Experimental results show that TitanCFI achieves overhead comparable to SoA hardware CFI solutions for most benchmarks, with lower area overhead, resulting in 1% of additional area occupation.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
