密码学报2023，Vol.10Issue(6)：1151-1164,14.DOI:10.13868/j.cnki.jcr.000657
BFV-MKFHE:基于BFV的多密钥全同态加密方案设计
BFV-MKFHE:Design of Multi-Key Fully Homomorphic Encryption Scheme Based on BFV
摘要
Abstract
The traditional fully homomorphic encryption scheme only supports data computations for single-key encryption,which cannot be adapted to the applications with multiple users.Multi-key fully homomorphic encryption can compute ciphertexts under different keys(for different users),and the final ciphertext is jointly decrypted by all relevant users.In order to extend the BFV homomor-phic encryption system to multi-key applications,a multi-key fully homomorphic encryption scheme BFV-MKFHE based on BFV is designed.This scheme is based on the BGV-based MKFHE scheme in CZW17.Firstly,the structure of the BGV encryption system is modified to that of BFV,where the modulus-switching in each layer is removed,which simplifies the algorithm operation process.Sec-ondly,in the relinearization process,the combined ciphertext of the user's private key is constructed to generate the evaluation key,and the modulus enhancement technique is used to optimize the re-linearization process,which reduces the noise generated in the homomorphic operation process and improves the evaluation key generation efficiency;Finally,the computational redundancy is reduced by modifying the rounding method of the encryption process.In the proposed scheme,the noise value generated when completing one homomorphic multiplication decryption is reduced to 1/p of that in the CDKS19 scheme,and the ciphertext size of the generated evaluation key is the same as that of the CDKS19 scheme,which is about 1/4 times smaller than that of the CZW17 scheme and that of the LZY+19 scheme,and there is no need to extend the ciphertext of the user's private key,which makes the computation more efficient.关键词
全同态加密/多密钥/BFV/密文扩展/重线性化Key words
fully homomorphic encryption/multi-key/BFV/ciphertext extension/relinearization分类
计算机与自动化引用本文复制引用
杨亚涛,赵东仓,李兆夫,刘亚奇..BFV-MKFHE:基于BFV的多密钥全同态加密方案设计[J].密码学报,2023,10(6):1151-1164,14.基金项目
北京市自然科学基金(4232034) （4232034）
中央高校基本科研业务费专项资金(328202225) （328202225）
"通信工程"、"电子信息工程"国家级一流本科专业建设点项目 Beijing Natural Science Foundation(4232034) （4232034）
the Fundamental Research Funds for the Central Uni-versities of China(328202225) （328202225）
National First-Class Undergraduate Dicipline Construction of"Communication Engi-neering"and"Electronic Information Engineering" （）
