The Research And Design Of Reconfigurable Cipher Processing Architecture

Cipher processing requires powerful data processing ability of the computing systems. Crypto standards change with the higher requirements of information security. Most modern security protocols are algorithm independent and support a variety of algorithms. The crypto algorithms in use are being changed according to the communicating session. The implementation of crypto standards must respond to these varieties. It's difficult for ASIC and general purpose microprocessor to achieve reasonable tradeoff of speed and flexibility.Reconfigurable devices can obtain high performance like ASIC and flexibility like microprocessor. The reconfigurable structure can match the characteristics of cipher processing more easily and achieve higher parallelism. The reconfigurable cipher processing architecture can change the implementation of cryptographic algorithms based on session negotiation, thereby can support large amount of ciphers. The flexibility of changing the cryptographic algorithms and keys also reduce the possibility of being attacked. The reconfigurable cipher processing architecture will be widely used in commerce and military fields.The structure of cryptographic algorithms has relatively fixed granularity and processing mode. The coarse-grain reconfigurable cipher processing architecture is an available structure that avoids lots of routing, reduces configuration storage and reconfiguration time. These characteristics make local, dynamic reconfiguration possible and simplify the algorithm mapping. For these reasons, we focus on coarse-grain reconfigurable cipher processing architecture in this paper and research for an efficient, agilely reconfigurable architecture. The main work and results are:1. Based on the observation that the data which are used in cipher processing have different changing frequencies, a Reconfigurable Unit for Cipher processing (RUC) model is firstly proposed from the view of input classification. RUC model can describe the main cipher processing function units, combinational circuits and sequential circuits in reconfigurable devices. It abstracts the key ideas of reconfigurable processing with arbitrary granularity and all kinds of modes to organize configuration data. Reconfigurable Cipher Architecture (RCA) model describes the characteristics of pipeline processing and local reconfiguration based on RUC. RCA and RUC provide a structural sketch, analysis methods and design rules for the research of reconfigurable cipher processing architecture.2. Base on RCA model, combining the characteristics of block ciphers and public-key ciphers, we propose a Reconfigurable Cipher Processing Framework (RCPF). RCPF is a pipelined prototype with alterable parallelism in which coarse-grain units are organized into a planar array following hierarchy principle. RCPF has distributedRAM to support S box lookup. Static and dynamic reconfiguration modes are used in RCPF in order to satisfy the computing requirement of algorithms in two cryptographic systems. Choosing different RCPF parameters' values can induce reconfigurable cipher processing architecture with different size and usability.3. The mapping mode of operations in public key cipher is relatively fixed. But with block cipher, the mapping operations are flexible. The method of operation splitting in RCPF is studied based on block cipher. Reasonable values of RCPF parameters are fixed based on the characteristics of public key cipher and block cipher. The Reconfigurable, Hierarchical Cipher processing Architecture (RHCA) is designed according to the determined values of RCPF parameters. RHCA adopts hierarchical permutation interconnection in the opinion of data alignment. It can process block ciphers and modular multiplications with uniformed function units, datapaths, hierarchical permutation networks, reconfiguration mechanisms and runtime controls. The uniformed architecture of RHCA achieves high flexibility in cipher processing.4. The parallel processing algorithm of the uniformed modular multiplication in RHCA is proposed. It guides the mapping o...