An implementation of ELiPS-based Ciphertext-Policy Attribute-Based Encryption

Pairing-based cryptography serves as a fundamental building block for a wide range of advanced cryptographic protocols, including Ciphertext-Policy Attribute-Based Encryption (CP-ABE), blockchain, zero-knowledge Succinct Non-interactive ARgument of Knowledge (zk-SNARKs), and Homomorphic Encryption (HE). A well-designed pairing library would catalyze progress in these specific applications and encourage innovation across various cryptographic protocols that rely on pairing. However, the CP-ABE framework relies on the PBC library, which has not been updated for a long time, needs higher security levels, and is vulnerable to multiple attacks, making it less practical. In contrast, the ELiPS library offers efficient operations related to pairing-based cryptography, delivering high performance while upholding a substantial security standard. To address the issues above, enhance performance, and strengthen security in CP-ABE, we adopt and implement the ELiPS as an efficient library for pairing systems into the CP-ABE framework, namely ELiPS-based CP-ABE. First, we generate a generator g. Then, we employ Shirase’s technique to convert asymmetric to symmetric pairing as the precondition of ELiPS. After that, we make several modifications to the CP-ABE framework and choose the appropriate ELiPS functions for integration. Finally, we validate our proposal through experiments involving data access authorization scenarios. The results confirm the effectiveness of our proposal, showcasing reduced computational costs for almost all functions except for the decryption cost.