• Privacy-preserving authorization for dual-blockchain supervision. • Distributed SM9 key issuance reduces KGC trust concentration. • TEE-assisted PRE enables chain-light and auditable cross-chain access. • Prototype results show practical latency in supervisory scenarios. Regional equity markets in China are deploying a regulatory-chain–business-chain dual-blockchain infrastructure to support supervisory coordination, process automation, and cross-region collaboration. However, cross-chain data sharing in this setting creates a persistent tension between regulatory accessibility and the confidentiality requirements of business participants. Existing blockchain-based authorization schemes are mostly designed for single-chain or generic multi-domain environments and do not simultaneously address supervision-oriented authorization semantics, reduced trust in key generation, and bounded on-chain overhead. To address this issue, we propose DLB-DAM, a privacy-preserving data authorization scheme tailored for the dual-layer regulatory architecture of regional equity markets. DLB-DAM combines distributed SM9-compatible identity-based encryption for cross-chain transmission, proxy re-encryption for controlled delegation, and trusted execution environments for off-chain handling of sensitive cryptographic operations, while smart contracts provide policy verification and auditable authorization records on chain. Under this design, plaintext data and long-term secrets remain outside the blockchain, and on-chain interactions are kept pseudonymous while still supporting regulatory tracing when required. We analyze the correctness and main security properties of DLB-DAM and implement a prototype on Hyperledger Fabric with TEE support. Experimental results indicate that DLB-DAM achieves practical latency and bounded contract overhead in typical non-high-frequency supervisory scenarios, suggesting its applicability to privacy-preserving authorization in dual-blockchain regulatory infrastructures.
Yang et al. (Fri,) studied this question.