An Identity-Based Adaptor Signature Scheme and its Applications in the Blockchain System
Zijian Bao, Debiao He, Cong Peng, Min Luo, Kim‐Kwang Raymond Choo · IEEE Open Journal of the Computer Society · 2023
Adaptor signature, as a new emerging cryptographic primitive, has become one promising method to mitigate the scalability issue on blockchain. It can transform an incomplete signature into a complete signature by revealing the witness of a pre-set hard relation, which can be applied to atomic swap, payment channel, payment hub, and other blockchain scenarios. Recently, a general transformation for constructing adaptor signatures has been proposed for some signature schemes with specific structures, e.g., Schnorr, ECDSA, SM2 signatures. However, we note that there is no identity-based adaptor signa-ture method so far. In this paper, we put forward an adaptor signature scheme for the identity-based signature scheme in the IEEE P1363 standard. Then, we formally prove the security of our scheme under the random oracle model. We also present the computation and communication costs, compared with other adaptor signatures. Finally, we show our scheme's potential use in atomic swaps and payment channel networks of blockchain.