dMCLAEKS: Pairing-free designated-tester multi-recipient certificateless authenticated encryption with keyword search for concealing search patterns

Modern Industrial Internet of Things (IIoT) technologies, such as smart grids, 5G-enabled unmanned aerial vehicles (UAV), and supply chain 4.0, can be leveraged to promote intelligent management. Yet, IIoT systems create enormous volumes of data that must be outsourced to the cloud for storage and to provide end-users with search capabilities. The outsourcing of IIoT data to a third-party cloud service provider (CSP) creates a number of data leakage issues. Recently, Certificateless Authenticated Encryption with Keyword Search (CLAEKS) was proposed to address the issue of encrypted data querying in cloud-assisted IIoT. But so far, the majority of existing techniques depend on expensive bilinear pairing, and they are all single-receiver. In addition, these methods are extremely vulnerable to keyword guessing attacks and do not hide the search pattern, making it simple for an attacker to deduce the search content. In this paper, we present a rapid and trustworthy designed-tester multi-recipient CLAEKS (dMCLAEKS) protocol with the numerous advantages: (1) no expensive bilinear pairing procedures; (2) supporting for ciphertexts with multiple recipients; (3) defending against Inside Keyword Guess Attacks (IKGA); (4) incapability to determine search pattern. A comparative between our suggested scheme and other similar schemes is also offered to demonstrate that the proposed method is stronger overall.