论文标题
经过认证的Everlasting功能加密
Certified Everlasting Functional Encryption
论文作者
论文摘要
密码学中的计算安全性有一种风险,即将来的确保基础假设被破坏。一种解决方案是构建理论上的信息协议,但已知许多加密原始图是不可能(或不可能)即使在量子世界中具有信息理论安全性的。一个不错的妥协(固有到量子)是经过认证的永恒安全性,这大致意味着以下内容。拥有量子加密数据的接收器可以发出证书,该证书表明接收器已删除了加密数据。如果证书有效,即使接收器在计算上无限制,也可以保证安全性。尽管已将几个加密原始图(例如承诺和零知识)获得了认证,但还有许多其他重要的原始词,这些原始素质尚未被认证为永恒的安全。 在本文中,我们介绍了经认证的Everlasting Fe。在此原始性中,带有消息M的密文的接收器和函数f的功能解密密钥可以获得F(m),而其他任何内容都没有。即使对手在发出有效证书后,对手也会在计算上不受限制。首先,我们为P/Poly电路构建经认证的Everlasting Fe,其中仅允许对手进行单个密钥查询。然后,我们将其扩展到Q结合的NC1电路,其中Q绑定的是Q键查询,允许使用A先验有限的多项式Q的对手。为了构建经过认证的Everlasting Fe,我们介绍并构建了经过秘密钥匙加密,公共键加密,接收器非承诺加密的经过认证的Everlasting版本,以及具有独立利益的垃圾计划。
Computational security in cryptography has a risk that computational assumptions underlying the security are broken in the future. One solution is to construct information-theoretically-secure protocols, but many cryptographic primitives are known to be impossible (or unlikely) to have information-theoretical security even in the quantum world. A nice compromise (intrinsic to quantum) is certified everlasting security, which roughly means the following. A receiver with possession of quantum encrypted data can issue a certificate that shows that the receiver has deleted the encrypted data. If the certificate is valid, the security is guaranteed even if the receiver becomes computationally unbounded. Although several cryptographic primitives, such as commitments and zero-knowledge, have been made certified everlasting secure, there are many other important primitives that are not known to be certified everlasting secure. In this paper, we introduce certified everlasting FE. In this primitive, the receiver with the ciphertext of a message m and the functional decryption key of a function f can obtain f(m) and nothing else. The security holds even if the adversary becomes computationally unbounded after issuing a valid certificate. We, first, construct certified everlasting FE for P/poly circuits where only a single key query is allowed for the adversary. We, then, extend it to q-bounded one for NC1 circuits where q-bounded means that q key queries are allowed for the adversary with an a priori bounded polynomial q. For the construction of certified everlasting FE, we introduce and construct certified everlasting versions of secret-key encryption, public-key encryption, receiver non-committing encryption, and a garbling scheme, which are of independent interest.