A Survey on Cloud Key Bank Privacy and Owner Sanction Enforced Key Management Framework

Abstract

Explosive magnification in the number of passwords for web predicated applications and encryption keys for outsourced data storage well exceed the management limit of users. Consequently outsourcing keys (including passwords and data encryption keys) to professional password managers (veracious-but-curious accommodation providers) is magnetizing the attention of many users. However, subsisting solutions in traditional data outsourcing scenario are unable to simultaneously meet the following three security requisites for keys outsourcing: 1)Confidentiality and privacy of keys; 2)Search privacy on identity attributes tied to keys 3)Owner controllable sanction over his/her shared keys. In this paper, we propose Cloud Key Bank, the first coalesced key management framework that addresses all the three goals above. Under our framework, the key owner can perform privacy and controllable sanction enforced encryption with minimum information leakage. To implement Cloud Key Bank efficiently, we propose an incipient cryptographic primitive denominated Searchable Conditional Proxy Re-Encryption (SC-PRE) which coalesces the techniques of Obnubilated Vector Encryption (HVE) and Proxy Re-Encryption (PRE) seamlessly, and propose a concrete SCPRE scheme predicated on subsisting HVE and PRE schemes. Our experimental results and security analysis show the efficiency and security goals are well achieved.