CRII: SaTC: Evolving I/O Protocols for Confidential Computing

云计算由于其可扩展性和成本节约，已迅速成为部署在线服务的标准方法，尽管它对数据安全和隐私构成了新的威胁。由于云服务提供商（CSP）操作硬件和特权软件，恶意CSP可以轻松访问或更改客户的敏感数据，而CSP软件中的漏洞可以允许攻击者这样做。为了提高云安全性，主要的芯片设计师最近增加了对机密计算的支持：在安全的硬件飞地中运行工作负载，其中工作负载的内存被加密，从而将其与CSP屏蔽。这一建议推进了将机密计算扩展到分布式服务的知识，这是一种越来越常见的云计算类型。 拟议的研究将为组织开发创新的开源系统软件，以便在不牺牲其隐私或用户隐私的情况下使用基本的云服务。为了培养下一代网络安全从业者，计划中的活动包括指导本科生和针对K-12学生的推广计划。该提案的核心研究问题是：（1）当系统中的某些节点是飞地时，协议必须如何处理身份验证和授权，以及（2）协议如何安全地包含可信和不可信节点的混合，包括攻击者入侵的节点。该提案针对两个重要的现有协议调查了这些问题：传输层安全性（TLS）和云对象存储。具体来说，该提案旨在扩展TLS以允许飞地使用一组身份（例如其启动度量，运行时度量和域名）进行身份验证，并探索使用联合签名方案来使这种身份验证高效而优雅。该提案支持复杂的端点身份验证，然后开发TLS的扩展，用于授权飞地如何共享数据，从而通过多方的分布式系统强制执行信息流。最后，该提案探索了存储协议扩展，通过使用高效的安全区辅助密钥轮换和数据重新加密，减轻共享加密云对象存储中密钥泄露的损害。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Cloud computing has quickly become a standard approach for deploying online services due to its scalability and cost savings, despite the new threats it poses for data security and privacy. As the cloud service provider (CSP) operates the hardware and privileged software, a malicious CSP can readily access or alter a customer’s sensitive data, while a bug in the CSP’s software can allow an attacker to do the same. To improve cloud security, the major chip designers recently added support for confidential computing: running a workload in a secure hardware enclave where the workload’s memory is encrypted, thus shielding it from the CSP. This proposal advances the knowledge for extending confidential computing to distributed services, an increasingly common type of cloud computing. The proposed research will develop innovative, open-source systems software for organizations to make use of essential cloud services without sacrificing their privacy or the privacy of their users. To prepare the next generation of cybersecurity practitioners, planned activities include the mentoring undergraduates and outreach programs for K-12 students.The proposal’s central research questions are: (1) how must protocols handle authentication and authorization when some nodes in the system are enclaves, and (2) how can protocols safely encompass a mix of trusted and untrusted nodes, including nodes that an attacker compromised. The proposal investigates these questions for two important existing protocols: Transport Layer Security (TLS) and cloud object storage. Specifically, the proposal seeks to extend TLS to allow an enclave to authenticate itself using a set of identities (such as its launch measurement, runtime measurement, and domain name), and explores the use of joint signature schemes to make such authentication efficient and elegant. Having support for complex endpoint authentication, the proposal then develops extensions to TLS for authorizing how enclaves may share data, thus enforcing the flow of information through a distributed system of diverse parties. Finally, the proposal explores storage protocol extensions that mitigate the damage of key compromise in a shared, encrypted cloud object store by using efficient, enclave-assisted, key rotation and data re-encryption.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.