Attribute-Based Heterogeneous Data Privacy Sharing in Blockchain-Assisted Industrial IoT

Industrial Internet of Things (IIoT) enables highly automated and intelligent cross-domain communication. Due to varying computational capabilities and security requirements, cross-domain IIoT data sharing involves the design of security protocols using different cryptosystems. Attribute-based searchable encryption enables fine-grained access control and ciphertext retrieval, but existing schemes are primarily designed on a singular cryptosystem, lacking support for searches on heterogeneous ciphertext. Moreover, related schemes still suffer from technical challenges, such as the single point bottleneck, caused by a single attribute authority, issues with attribute updates, and forward secrecy attacks. In this article, we propose an attribute-based heterogeneous data privacy sharing (AB-HDPS) scheme for blockchain-assisted IIoT. Attribute-authorized users within a public key infrastructure cryptosystem can search ciphertext from data owners in a certificateless cryptosystem. The scheme utilizes multiple authorities to generate attribute keys, employs a glass-box traceable mechanism to prevent misuse of attribute keys, and implements subset-cover trees for attribute revocation. Specifically, leveraging the immutability of blockchain, the AB-HDPS scheme supports traceability and auditing of user access. Security analysis shows that the AB-HDPS scheme can resist internal keyword guessing and chosen-plaintext attacks, and it satisfies forward security. Comparative experimental simulations demonstrate that the AB-HDPS scheme with outsourced decryption has satisfactory computational performance, and the performance of the blockchain system within the scheme is commendable.