Analysis and improvement of an identity-based signature scheme from lattices

Liu et al proposed an identity-based signature from lattices in 2013, and proved that it can achieve strong unforgeability in the standard model. Through analysis, the security proof of this scheme has some defect, and then show that the scheme cannot prove the strong unforgeability under selective identity and adaptive chosen-message attacks. Then, using Boyen signing technique (PKC 2010) inpoves the signing algorithm, and proves the strong unforgeability under selective identity and adaptive chosen-message attacks (SU-sID-CMA) in the standard model. In addition, it compares the efficiency and security of the scheme and the other identity-based signatures from lattices.