报告人：杨如鹏

报告地点：淦昌苑D座320

报告时间：2025-05-14 09:00—11:00

报告摘要：

We construct fully homomorphic encryption (FHE) schemes with chosen-ciphertext (CCA) security from the learning with errors (LWE) assumption in the standard model. Security of our construction only relies on the circular-secure LWE, which matches the assumptions needed for FHE with the basic chosen-plaintext security. Besides, the scheme achieves a security notion that is strictly stronger than the CCA1 security. Prior FHE schemes with even just CCA1 security require either the random oracle model or non-falsifiable knowledge assumptions.

The construction follows the well-known Naor-Yung double encryption paradigm. However, unlike previous works [Boneh et al., ITCS 2012; Canetti et al., PKC 2017; Manulis and Nguyen, Eurocrypt 2024], which employ general zero-knowledge succinct non-interactive arguments of knowledge (ZK-SNARKs), we design a special succinct argument to prove the validity of FHE ciphertexts. The succinct argument is constructed from batch arguments for NP and a new primitive called predicate extractable commitment, which may be of independent interest.

The talk is based on a joint work with Zuoxia Yu and Willy Susilo.

报告人简介：

杨如鹏，澳大利亚伍伦贡大学讲师，2019年毕业于3044永利官网计算机学院。主要研究兴趣包括基于格的密码方案设计，密码水印，零知识证明，公钥加密等。在CRYPTO，EUROCRYPT, ASIACRYPT 等国际会议发表系列成果。

邀请人：胡程瑜

审核人：魏普文