GGM下函数加密的可模拟安全及证明工具设计
SIM Security of Functional Encryption Schemes in GGM and Design of Proof Tool
孔若伊 1王更 1谷大武1
作者信息
- 1. 上海交通大学 电子信息与电气工程学院,上海 200240
- 折叠
摘要
函数加密是一种新型原语,通过函数密钥解密可以得到关于消息的函数值,而不会泄露消息的其他信息.通用群模型(generic group model,GGM)是一种可以用来分析方案构造安全性的理想化模型.由于目前还没有针对GGM的有效攻击,且能在GGM下证明安全的方案都比较高效,越来越多的函数加密方案在 GGM 下证明安全性.2017 年,Baltico 等人提出了第一个公钥二次函数加密方案,并在 GGM下证明了自适应的不可区分安全性.然而,目前无论是在标准假设还是 GGM 下,没有能达到自适应可模拟安全性的公钥二次函数加密方案.本文根据公钥二次函数加密可模拟安全的定义,证明了 Baltico 等人提出的方案在 GGM 下具有更强的自适应可模拟安全性.由于证明过程繁琐,本文借助计算机辅助,设计了在 GGM 下证明公钥二次函数加密方案具有可模拟安全性的自动证明工具.该工具是第一个针对函数加密方案设计的自动证明工具,且该工具不仅能快速测试在 GGM 下构造的函数方案是否具有可模拟安全性,还可以作为标准假设下构造安全函数加密方案的初步验证.
Abstract
Functional encryption(FE)is a new cryptographic primitive where each secret key is associated with a function and ciphertext is associated with a message.Given a secret key and a ciphertext,a decryptor can learn the function value of a message without leaking additional information about the message.The generic group model(GGM)is an idealized model that can be used to analyze the security of scheme construction.Since there are no effective attacks against it and it often admits schemes that are simpler and more efficient,many functional encryption schemes are proved secure in the GGM.In 2017,Baltico et al.proposed the first public-key quadratic functional encryption scheme and proved it adaptively indistinguishable security in the GGM.Nevertheless,no public-key functional encryption scheme can achieve adaptively simulation-based security in both the standard models and GGM.According to the definition of public-key quadratic functional encryption with simulation-based security,Baltico's scheme adaptively simulation-based security is proved in the GGM,which will enhance the security of the scheme.Since the proof process is complicated,an automatic proof tool is designed for proving public-key quadratic functional encryption schemes with simulation-based security in the GGM.This tool is the first automatic proof tool designed for functional encryption schemes,and it not only can quickly test simulation-based security of functional encryption schemes in the GGM,but also can be used as a preliminary verification of constructing secure functional encryption schemes in the standard models.
关键词
公钥二次函数加密/通用群模型/自适应可模拟安全/自动证明工具Key words
public-key quadratic functional encryption/generic group model(GGM)/adaptively simulation-based security/automatic proof tool引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据