With the dramatically increasing deployment of intelligent devices, the Internet of Things
(IoT) has attracted more attention and developed rapidly. It effectively collects and shares
data from the surrounding environment to achieve better IoT services. For data sharing, the
publish-subscribe (PS) paradigm provides a loosely coupled and scalable communication
model. However, due to the loosely coupled nature, it is vulnerable to many attacks, resulting
in some security threats to the IoT system, but it cannot provide the basic security
mechanisms such as authentication and confidentiality to ensure the data security. Thus, in
order to protect the system security and users’ privacy, this paper presents a secure
blockchain-based privacy-preserving access control scheme for the PS system, which adopt
the fully homomorphic encryption (FHE) to ensure the confidentiality of the publishing
events and leverage the ledger to store the large volume of data events and access
crossdomain information. Finally, analyze the correctness and security of our scheme;
moreover, we deploy our proposed prototype system on two computers and evaluate its
performance. The experimental results show that in PS system can efficiently achieve the
equilibrium between the system cost and the security requirement.