Design and implementation of an encrypted cloud storage system based on OpenStack Swift

To solve the issues of user data security and sharing in the cloud storage environment, we studied the methods to build an encrypted cloud storage system with sharing mechanism. This paper provides a method to build such a system on the basis of the existing OpenStack Swift storage service. Then the architecture design of this system is given, which includes the use of the combination of public-key encryption scheme and symmetric-key encryption scheme to encrypt user's private data and protect its security. An architecture design of proxy re-encryption is given, which enables users to safely share encrypted data. And then we presented the implementation of the prototype system, as long as the test results of this system. This system is safe under the DBDH (Decisional Bilinear Diffie-Hellman) assumption and compatible with the existing OpenStack Swift system, and it's of reference value for the design and implementation of encrypted cloud storage systems.