Researching Security Mechanisms Of S-box Based On The Polymorphic Cipher

An S-box is the important nonlinear component of block cipher algorithms. In f-act, the algorithm of S-box construction enjoys extremely highly nonlinear and h-igh level of confusion and diffusion. In contrast to most or all commonly known symmetric encryption algorithm designs (including the AES candidates such as Rijndael and Twofish), the Polymorphic Cipher (PMC) proposed by C.B.Roellgen can be made immune to Differential Power Attack. The algorithm is mostly us-ed to encrypt disk files. We propose a new method for constructing a Pseudora-ndom Number Generator (PRNG) to construct the security fast S-box. In this di-ssertation, we analyze the security of the S-box with cryptographic test methods such as strict avalanche criteria, high nonlinearity and bit independence criteria. It consists of the following four aspects.1. By combining the characteristics of P2P network with the improved Polymo-rphic Cipher (PMC) theory, we improve on the signal generator to construct the security Polymorphic PRNG with some pseudorandom iterative one-way Boolean functions. The PRNG provides mass-produced session keys for two parties across a communication channel. The security of the function is anal-yzed by some experiment al results and correlated theories.2. We propose a self-compiling-based Polymorphic Diffie-Hellman key excha-nge algorithm. We propose sixteen candidate one-way Boolean functions ba-sed on the Polymorphic Cipher (PMC) proposed by C.B.Roellgen. By combi-ning the characteristics of a perfect hash function and unobtainable self-com-pile system, we improve on the original memory medium oriented Diffie-He-llman key exchange algorithm. We propose the scheme that both commun-ication parties construct a new polymorphic Diffie-Hellman key exchange algorithm. The scheme can plug up the leaks in identity authentication, block DOS and impersonation attack.3. We propose a much more secure scheme of semi-S-box key exchange agree-ment based on the Diffie-Hellman key exchange algorithm. The identity i-nformation of two parties can be appended to the agreement. Its security is dependent upon the length of pseudorandom numbers generated by two com-munication parties. The polymorphic S-box becomes a broad agreement in ir- regular scenes.4. To satisfy a variety of cryptographic test methods, such as strict avalanche criterion (SAC), bit independence criterion (BIC), and nonlinearity, we apply polymorphic cipher (PMC) theory to the permutation function construction. Correlations among the test criteria in a real network environment are also evaluated. The most important work is to optimize the polymorphic ciphers combinational functions. Given that we are able to construct a polymorphic S-box design for a large amount of fast keys between two communication parties.