Identity-Based Blind Signature from Lattices in Standard Model

摘要

Blind signature allows a user to get a signature of a signer on an arbitrary message, without leaking any information about the message. The verifier can check that whether the signature is indeed generated by the signer, and the signer cannot recall the signing situation. This property is essential when the signed message needs privacy protection for the user, like a bank bill or a trade secret. Lattice-based system is the most promising quantum-resistant primitive, and the first lattice-based blind signature is proposed by Rueckert For another, identity-based system is an alternative to public key infrastructure, as it can simplify the key management procedures in certificate-based public key systems. Illuminated by the demand of identity-based blind signature in the post-quantum circumstance, we consider the lattice-based identity based blind signature (IBBS) based on hard worst-case lattice problems. Besides, all existing lattice-based blind signatures are constructed and proved to be secure in the random oracle model. In this work, we construct an identity-based blind signature from lattices in the standard model. Our construction is proved to be one-more unforgeable under the selective identity and chosen message attacks (sID-CMA), and unconditionally blind in the standard model.