The current zero trust model adopted in System-on-Chip (SoC) design is vulnerable to various malicious entities, and modern SoC designs must incorporate various security policies to protect sensitive assets from unauthorized access. These policies involve complex interactions between multiple IP blocks, which poses challenges for SoC designers and security experts when implementing these policies and for system validators when ensuring compliance. Difficulties arise when upgrading policies, reusing IPs for systems targeting different security requirements, and the subsequent increase in design time and time-to-market. This paper proposes a generic and flexible framework, called DiSPEL, for enforcing security policies defined by the user represented in a formal way for any bus-based SoC design. It employs a distributed deployment strategy while ensuring trusted bus operations despite the presence of untrusted IPs. It relies on incorporating a dedicated, centralized module capable of implementing diverse security policies involving bus-level interactions while generating the necessary logic and appending in the bus-level wrapper for IP-level policies. The proposed architecture is generic and independent of specific security policy types supporting both synthesizable and non-synthesizable solutions. The experimental results demonstrate its effectiveness and correctness in enforcing the security requirements and viability due to low overhead in terms of area, delay, and power consumption tested on open-source standard SoC benchmarks.

翻译：当前SoC（片上系统）设计中采用的零信任模型易受各类恶意实体攻击，现代SoC设计必须集成多种安全策略以保护敏感资产免遭未授权访问。这些策略涉及多个IP核间的复杂交互，给SoC设计者和安全专家在实施策略时带来挑战，同时也增加了系统验证人员确保合规性的难度。当升级策略、将IP复用于面向不同安全要求的系统时，会出现设计周期延长与上市时间增加等问题。本文提出一种通用灵活的框架——DiSPEL，用于以形式化方式强制执行用户定义的安全策略，适用于任何基于总线的SoC设计。该框架采用分布式部署策略，确保即便存在不可信IP的情况下仍能保障总线操作的可信性。其核心在于集成一个专用集中式模块，该模块不仅能实现涉及总线级交互的多样化安全策略，还能生成必要逻辑并将其附加至处理IP级策略的总线级封装器中。所提架构具有通用性，不依赖于特定安全策略类型，同时支持可综合与不可综合两种解决方案。实验结果表明，该框架在强制执行安全需求方面具有有效性与正确性，且在开源标准SoC基准测试中，其面积、延迟和功耗开销较低，验证了可行性。