Smart home IoT systems utilize trigger-action platforms, e.g., IFTTT, to manage devices from various vendors. However, they may be abused by triggering malicious rule execution with forged IoT devices or events violating the execution integrity and the intentions of the users. To address this issue, we propose a ledger based IoT platform called Ruledger, which ensures the correct execution of rules by verifying the authenticity of the corresponding information. Ruledger utilizes smart contracts to enforce verifying the information associated with rule executions, e.g., the user and configuration information from users, device events, and triggers in the trigger-action platforms. In particular, we develop three algorithms to enable ledger-wallet based applications for Ruledger and guarantee that the records used for verification are stateful and correct. Thus, the execution integrity of rules is ensured even if devices and platforms in the smart home systems are compromised. We prototype Ruledger in a real IoT platform, i.e., IFTTT, and evaluate the performance with various settings. The experimental results demonstrate Ruledger incurs an average of 12.53% delay, which is acceptable for smart home systems.

翻译：智能家居物联网系统利用触发-动作平台（例如IFTTT）管理来自不同厂商的设备。然而，这些平台可能被滥用：通过伪造物联网设备或事件触发恶意规则执行，从而破坏执行完整性和用户意图。为解决此问题，我们提出一种基于账本的物联网平台Ruledger，通过验证相应信息的真实性来确保规则的正确执行。Ruledger利用智能合约实施对规则执行相关信息的验证，例如来自用户的用户信息和配置信息、设备事件以及触发-动作平台中的触发器。具体而言，我们开发了三种算法，为Ruledger实现基于账本钱包的应用，并确保用于验证的记录具有状态性和正确性。因此，即使智能家居系统中的设备和平台被攻破，规则的执行完整性也能得到保障。我们在真实物联网平台IFTTT上实现Ruledger原型，并在多种设置下评估其性能。实验结果表明，Ruledger平均引入12.53%的延迟，这对智能家居系统而言是可接受的。