Certificateless searchable encryption with cryptographic reverse firewalls for IIoT

Integrating the Industrial Internet of Things (IIoT) and cloud computing is increasingly prevalent in modern business. However, to safeguard data privacy in the cloud server (CS), sensitive information must be encrypted prior to uploading to a CS. The real challenge is searching encrypted data without compromising speed or security. Public Key Encryption with Keyword Search (PEKS) schemes enable the search of ciphertexts without exposing sensitive information. This article introduces a novel Certificateless Searchable Encryption with Cryptographic Reverse Firewalls (CL-SE-CRF). Meanwhile, the proposed scheme addresses the PEKS limitations by removing the requirement for conventional certificate management and addressing concerns related to key escrow. In addition, the security analysis demonstrates that the CL-SE-CRF scheme can prevent and resist keyword guessing attacks (KGA), algorithm substitution attacks (ASA), and chosen keyword attacks (CKA). Furthermore, experimental results demonstrate that the CL-SE-CRF significantly reduces communication and computation costs in the IIoT compared to similar protocols. Therefore, the proposed scheme is helpful for IIoT applications.