CAREER: Foundations and Extensions of Public Key Cryptography

职业：公钥密码学的基础和扩展

• 批准号: 0952692
• 负责人: Brent Waters
• 金额: $ 44.66万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0952692&HistoricalAwards=false
• 关键词: CAREER; Foundations; Extensions; Public; Key

Increasingly, both personal and enterprise data are being stored at third-party locations, outside of the data owner's control. A company might directly outsource its data storage by using a backup service such as Amazon's S3 application. In other cases, outsourcing is a by-product of a larger service; for example, several corporations use Salesforce to manage their customer relations and sales data. Outsourcing data storage offers several benefits: storage costs can be amortized by a third-party over several customers, a third party can store data at different geographic locations for robustness, and integration with larger application services becomes easier. One can imagine a not too distant future where most computation and storage is realized in a network "cloud". In order to protect data stored at third party services we will need to encrypt it.Unfortunately, traditional encryption systems are insufficient for these applications. Solving this problem requires an entirely new way of encrypting data. To see this, recall that in traditional public key encryption a party encrypts data to a single known user. While this functionality is useful for applications such as encrypted email and establishing secure web sessions, it lacks the expressiveness needed for more advanced data sharing. In enterprise settings, a party will want to share data with groups of users based on their credentials. Often a party sharing data will not know which individual users will need to have access to it; moreover, some users will not even exist in the system at the time the data is encrypted. For example, a traveling sales representative might want to encrypt records so that any current or future manager in the personal electronics division can access them.The proposed research is laying the foundations for an entirely different vision for encryption called Functional Encryption. Instead of encrypting to individual users, in a functional encryption system, one can embed any access predicate f() into the ciphertext itself. Functional encryption simultaneously renders completely general functionality and its data access is self-enforcing --- requiring no trusted mediator. The PI aims to create a system where the encrypting party can specify any access predicate over a recipient's credentials (i.e. f can be any Turing Machine). Functional encryption for any predicate opens up a world of possibilities for data sharing; one could encrypt an image such that the access function f encoded an image recognition program allowing only people in the picture to view it.In addition to broadening our view of public key cryptography, the PI will explore fundamental problems in public key encryption. One direction is to attempt to build chosen ciphertext secure encryption from standard public key encryption. Finally, the PI will explore the foundations of building public key cryptography.

越来越多的个人和企业数据被存储在数据所有者无法控制的第三方位置。一家公司可以通过使用备份服务（如Amazon的S3应用程序）直接外包其数据存储。在其他情况下，外包是一个更大的服务的副产品;例如，几家公司使用Salesforce来管理他们的客户关系和销售数据。 外包数据存储提供了几个好处：存储成本可以由第三方分摊给多个客户，第三方可以将数据存储在不同的地理位置以实现鲁棒性，并且与大型应用程序服务的集成变得更容易。人们可以想象一个不太遥远的未来，其中大多数计算和存储都在网络“云”中实现。为了保护存储在第三方服务中的数据，我们将需要对其进行加密。不幸的是，传统的加密系统不足以满足这些应用。解决这个问题需要一种全新的数据加密方法。要了解这一点，请回想一下，在传统的公钥加密中，一方将数据加密给单个已知用户。虽然此功能对于加密电子邮件和建立安全Web会话等应用程序很有用，但它缺乏更高级数据共享所需的表现力。在企业设置中，一方希望根据用户的凭据与用户组共享数据。 通常，共享数据的一方不知道哪些用户需要访问它;此外，在数据加密时，一些用户甚至不存在于系统中。例如，一个旅行的销售代表可能想加密记录，以便个人电子产品部门的任何现任或未来的经理都可以访问它们。拟议的研究为一种完全不同的加密愿景奠定了基础，称为功能加密。在功能加密系统中，可以将任何访问谓词f（）嵌入到密文本身中，而不是对单个用户进行加密。功能加密同时呈现完全通用的功能，其数据访问是自我强制的-不需要可信的中介。 PI旨在创建一个系统，其中加密方可以在接收方的凭证上指定任何访问谓词（即f可以是任何图灵机）。任何谓词的函数加密为数据共享开辟了一个可能性的世界;人们可以加密图像，使得访问函数f编码图像识别程序，只允许图片中的人查看它。除了拓宽我们对公钥密码学的看法，PI将探索公钥加密的基本问题。 一个方向是尝试从标准公钥加密中构建选择的密文安全加密。 最后，PI将探索构建公钥密码学的基础。