Achieving Strong Security and Verifier-Local Revocation for Dynamic Group Signatures from Lattice Assumptions

摘要

Both member registration and member revocation are essential features in group signature schemes. In ASIACRYPT 2016 Libert, Ling, Mouhartem, Nguyen, and Wang suggested a simple joining mechanism with their lattice-based group signature scheme with member registration. However, their scheme does not support member revocation. Verifier-local revocation is a member revocation approach in group signature schemes, which only requires the verifiers to keep the revocation messages while existing members have no burden. Since there is no workload for existing members related to revocation messages, verifier-local revocation method became the most suitable revocation approach for any environment. However, original group signature schemes with verifier-local revocability satisfy weaker security. This paper adds verifier-local revocation mechanism to the Libert's (ASIACRYPT 2016) scheme to produce a fully dynamic lattice-based group signature scheme with member registration and member revocation using verifier-local revocation mechanism. Moreover, the resulted scheme achieves stronger security than the security in the original group signature schemes with verifier-local revocation.