Smart home systems have become more and more prevailent in recent years. On the one hand, they make our everyday life more convenient; on the other hand, they suffer from the two notorious security problems, namely, the open-port problem and the overprivilege problem, making their security situations extremely worrying and uncheerful. In this article, we proposed HomeShield, a novel credential-less authentication framework to shield smart home systems by effectively defending against the attacks resulted from these two security problems without the need for sensitive credentials. We further detailed an implementation of HomeShield based on the side channels that are publicly available in Android smartphones serving as controllers of smart home systems and presented its workflow in protecting against various attacks caused by the open-port and overprivilege problems. Finally, we tested our HomeShield implementation on a real-world smart home system and considered four threat models that cover basically all practical attacks, including Mirai and its variants. We also considered the effectiveness of our HomeShield implementation on the SmartApps of the Samsung SmartThings platform, which also suffers from the open-port and overprivilege problems, even though its overprivilege issue has been extensively studied by the recently proposed works, such as ContexIoT and SmartAuth. The evaluation results indicate that our HomeShield realization can successfully defend against over 90% attack trials with an average latency of less than 1 s.

中文翻译：

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HomeShield：用于智能家居系统的无凭据认证框架

近年来，智能家居系统越来越流行。一方面，它们使我们的日常生活更加便利。另一方面，它们遭受两个臭名昭著的安全问题，即开放端口问题和特权过多问题，这使他们的安全状况极为令人担忧和平静。在本文中，我们提出了HomeShield，这是一种新颖的无凭据身份验证框架，可通过有效防御这两个安全问题导致的攻击而无需敏感凭据，从而保护了智能家居系统。我们进一步详细介绍了基于侧通道的HomeShield实施，该通道可在充当智能家居系统控制器的Android智能手机中公开使用，并介绍了其工作流程，可防止由开放端口和特权问题引起的各种攻击。最后，我们在现实的智能家居系统上测试了HomeShield的实现，并考虑了四种威胁模型，这些模型基本上涵盖了所有实际攻击，包括Mirai及其变体。我们还考虑了在三星SmartThings平台的SmartApps上实施HomeShield的有效性，该平台也遭受了开放端口和特权问题的困扰，尽管最近提议的工作（例如ContexIoT和SmartAuth）已经对其过度特权问题进行了广泛研究。 。