随机预言
计算机科学
加密
一般化
基于属性的加密
功能加密
标准模型(数学公式)
计算机安全
密文
理论计算机科学
订单(交换)
公钥密码术
数学
历史
考古
经济
数学分析
量具(枪械)
财务
作者
Pratish Datta,Ilan Komargodski,Brent Waters
标识
DOI:10.1007/978-3-031-30620-4_15
摘要
Decentralized multi-authority attribute-based encryption ( $$\textsf{MA}\text {-}\textsf{ABE}$$ ) is a distributed generalization of standard (ciphertext-policy) attribute-based encryption where there is no trusted central authority: any party can become an authority and issue private keys, and there is no requirement for any global coordination other than the creation of an initial set of common reference parameters. We present the first multi-authority attribute-based encryption schemes that are provably fully-adaptively secure. Namely, our construction is secure against an attacker that may corrupt some of the authorities as well as perform key queries adaptively throughout the life-time of the system. Our main construction relies on a prime order bilinear group where the k-linear assumption holds as well as on a random oracle. Along the way, we present a conceptually simpler construction relying on a composite order bilinear group with standard subgroup decision assumptions as well as on a random oracle. Prior to this work, there was no construction that could resist adaptive corruptions of authorities, no matter the assumptions used. In fact, we point out that even standard complexity leveraging style arguments do not work in the multi-authority setting.
科研通智能强力驱动
Strongly Powered by AbleSci AI