ISSN 1000-1239 CN 11-1777/TP

• 信息安全 •

### 基于格的前向安全无证书数字签名方案

1. (同济大学电子与信息工程学院计算机科学与技术系 上海 201804) (1062842783@qq.com)
• 出版日期: 2017-07-01
• 基金资助:
国家重点研发计划项目(2017YFB0802302)

### Lattice-Based Forward Secure and Certificateless Signature Scheme

Xu Qian, Tan Chengxiang, Feng Jun, Fan Zhijie, Zhu Wenye

1. (Department of Computer Science and Technology, College of Electronics and Information Engineering, Tongji University, Shanghai 201804)
• Online: 2017-07-01

Abstract: Certificateless signature scheme has solved key escrow problems existing in traditional identity-based signature schemes. The secret key of the user in certificateless signature scheme consists of two parts, one is partial secret key, which is generated by key generation centre, and the other is secret value from user itself. However, there are still three points to be improved in such scheme. Firstly, although some lattice-based certificateless signature schemes based on the random oracle model have been proposed in order to achieve the post-quantum security, their standard model counterparts remain unrealized. Secondly, most of the existing lattice-based certificateless signature schemes only consider the outside attacker and neglect the threats from semi-trusted user. Thirdly, the existing certificateless signature schemes all rely on the security of the secret key, which cannot be satisfied due to the key exposure problem. In this paper, based on the forward secure and certificateless signature scheme in the random oracle model, we propose the first lattice-based certificateless signature scheme which is provably secure in the standard model to eliminate key exposure and key escrow problems without introducing a third party proxy. With the help of the small integer solution problem, we have proved that our schemes can guarantee the forward secure and strongly existential unforgeability against the adaptive chosen message and adaptive chosen identity attack.