虚拟黑盒安全的程序混淆理论及应用研究

发布时间：2017-12-28 05:44

本文关键词：虚拟黑盒安全的程序混淆理论及应用研究　出处：《湖北工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：程序混淆(program obfuscation)是一个编译器,它可以将一个程序(电路)转换为一个可执行的混淆过的程序,混淆后的程序在功能上与原程序保持一致,混淆后的电路大小与原程序保持在同一个数量级,并且无法从混淆后的程序中获得任何原程序中的有用信息。程序混淆在软件保护、外包云计算、含有敏感信息的代理操作中有很大的实用价值,同时程序混淆在密码学领域也有非常大的研究意义,目前已经提出了对点函数(point function)、多比特输出的点函数(multi-bit output point obfuscation)、不可否认加密函数(deniable encryption)等函数的安全混淆。目前,程序混淆已经成为当前密码学领域中研究的热点和难点,在2001年欧密会上,Barak等人已经证明在基于断言的定义下,不存在对所有图灵机或所有电路的通用混淆。在过去的几年中,程序混淆在复杂密码学上取得了一些重大的突破,2007年Hohenberger提出了重加密函数的安全混淆,这是首个针对复杂密码函数的安全混淆,随后越来越多的混淆被提出。本文对近年来提出的特殊函数的安全混淆进行了总结和分析,提出了一个匿名的重加密函数的安全混淆和一个EVES(encrypted verifiable encrypted signature)函数的安全混淆,并分别进行了安全性证明。本文主要研究如下:(1)介绍了几种密码函数的混淆,详细分析了重加密函数、加密签名函数的构成和混淆算法,并深入研究了这两种混淆算法的安全性证明。(2)构造了一个特殊的匿名重加密算法,对其进行了安全混淆,并证明了混淆后的程序达到了虚拟黑盒安全。我们首先给出了一个两种形式的加密方案,这两种加密方案都达到了CCA安全,加密后的?(28)0的密文可以被重加密为?(28)1的密文,但是?(28)1的密文不可以再被重加密。这个混淆后的重加密程序可以在任意不可信的第三方代理或者云服务器上运行,并且不会泄漏程序中的敏感信息。(3)构造了一个特殊的EVES函数,对其进行了安全混淆,并证明了混淆后的程序的安全性。此方案是一个VES方案和线性加密方案的结合,混淆后的EVES程序可以在任意不可信的第三方代理或者云服务器执行,程序会为签名者产生一个加密的签名,并且无法获得签名者的私钥。
[Abstract]:(program obfuscation) program obfuscation is a compiler, it can be a program (circuit) into an executable obfuscated program, the program after obfuscation is consistent with the original program in function, circuit size and confusion after the original program remained in the same order of magnitude, and can not get any useful information in the original program from the obfuscated program. The program confusion has great practical value in the software outsourcing agency operation protection, cloud computing, containing sensitive information, but also has the significance of the research program obfuscation is very large in the field of cryptography, have been proposed to function (point, function) multi bit output function (multi-bit output point obfuscation), can not be deny the encryption function (deniable encryption) security confusion function. At present, the program confusion has become a hot and difficult research at present in the field of cryptography, in EUROCRYPT 2001, Barak et al have demonstrated in assertion based definition, there is no general confusion of all Turing machines or all circuits. In the past few years, program obfuscation has made some significant breakthroughs in complex cryptography. In 2007, Hohenberger proposed the security confusion of re encryption function, which is the first security confusion for complex cryptographic functions, and then more and more confusion has been put forward. This paper summarizes and analyzes the security confusion of special functions proposed in recent years. It proposes an anonymous double encryption function's security obfuscation and a EVES (encrypted verifiable encrypted signature) function's security confusion, and has carried on the security proof separately. This paper is mainly studied as follows: (1) the confusion of several cryptographic functions is introduced, and the composition and obfuscation algorithm of re encryption function, encrypted signature function are analyzed in detail, and the security proofs of the two obfuscation algorithms are further studied. (2) a special anonymous re encryption algorithm is constructed to confuse it safely, and it is proved that the confusing program achieves the security of the virtual black box. First, we give a two form of encryption scheme. These two encryption schemes all achieve CCA security. After encrypting, (28) 0 ciphertext can be re encrypted as (28) 1 ciphertext, but (28) 1 ciphertext can no longer be re encrypted. The obfuscation of the re encrypted program can run on any untrusted third party agent or cloud server, and does not leak sensitive information in the program. (3) a special EVES function is constructed to confuse it safely, and the security of the confusing program is proved. This scheme is a combination of VES scheme and linear encryption scheme. The EVES program can be executed on any untrusted third party agent or cloud server. The program generates an encrypted signature for the signer, and can not get the private key of the signer.
【学位授予单位】：湖北工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP314;TP309

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