Hardware acceleration of cryptographic procedures for secure distributed storage systems

Abstract

Cloud computing gives new opportunities to many applications. The advantages of reducing the cost and complexity of up-front infrastructure are accompanied with various security issues. A cloud storage provider has to be trusted to handle ones data confidentially and ensure its availability. In order to guarantee the secrecy and availability of sensitive data, it is unavoidable for the end-user to encrypt and replicate the data in any way. An approach for these issues is to store the data in a virtual cloud formed of multiple cloud providers. With a scheme called secret sharing a free selectable amount of redundancy is added. The data to be protected is split into multiple pieces and distributed to several servers. To restore the original data a certain amount of arbitrary pieces is required. In this way, the failure of a single server in the cloud does not influence the availability. Moreover, this schemes enables high secrecy as only a certain amount of pieces reveal the original information. Any party holding less pieces are not capable of obtaining any information of the original data. It is of high computational effort to split the data in such a manner. While various software solutions exist, there are only few investigations in hardware. However, the implantation in dedicated hardware allows the possibility of high performance increase and has the potential to expand its applicability. This work firstly handles the implementation of an information theoretical secure secret sharing scheme, proposed by Adi Shamir. Subsequently, it discusses and presents the implementation of a more efficient scheme in terms of storage space, the Computational Secret Sharing. All these investigations are targeted for a Field Programmable Gate Array (FPGA). A final implementation of a complete secret sharing system operating in a network environment and the capability of managing, sharing and distributing complete filles as well as successfully restoring them completes this work.