UA133746U - METHOD OF CRYPTOGRAPHICAL TRANSFER OF INFORMATION - Google Patents

Abstract

The method of cryptographic transformation of information is that the information sequence is presented in the form of bit blocks that are subject to iterative processing by primitive cryptographic transformations: permutation - using blocks of mixing cubes (P-blocks); substitution - by means of substitution blocks (S-blocks); functional cyclic shift and modulation operations 2 (ShiftRow) - using appropriate devices, functional sliding coding operations (SlidCode) - using mixed Gray codes. The bit blocks of the information sequence are presented in the form of three-dimensional matrices (cubes), as the S-block form a variable three-dimensional matrix of substitutions, which is constructed by obtaining a multiplicatively inverse element x-1 over the extended Galois finite field GF (28) and by performing the affine transformation y = M (x-1 + (over the primitive Galois binary field GF (2)), while the affine transformation matrix M uses variable inverted symmetric matrices, which are selected according to the value of the cycle key, functional mixing operations I and cyclic shift and addition modulo 2 and sliding coding are not fixed, but depend on the state of the key, iterative processing of primitive cryptographic transformations occurs in the following sequence: substitution, permutation, functional operations cyclic shift and addition (ShiftRow), Functional Sliding Encoding (SlidGode).

Description

The utility model belongs to the field of cryptographic information protection and can be used in encryption tools in information processing systems to expand their capabilities.

A known method of cryptographic transformation (|1|, which is based on the fact that the information sequence is presented in the form of 64-bit blocks, which are subject to iterative processing by primitive cryptographic transformations: permutation (reptiiayop) - using permutation blocks (P-blocks); substitution (zIyB5iyshiop ) - with the help of substitution blocks (5-blocks); functional operations of cyclic shift and addition modulo 2 - with the help of appropriate devices. Iterative processing consists in repeatedly performing the same groups of transformations that provide the necessary conditions for the stability of the cryptographic transformation: scattering (using P -blocks) and shuffling (using 5-blocks) of information data.

The disadvantages of this method are that for the cryptographic transformation of information as a 5-block, a fixed matrix of substitutions is used, which does not allow to flexibly change the parameters of cryptographic processing and dynamically control the process of shuffling information data, as well as the fact that for the functional shuffling operation, fixed parameter values are used landslide

The closest one, chosen as the closest analogue, is the improved method of cryptographic transformation |2), which is based on the fact that the information sequence is presented in the form of bit blocks, which are subject to iterative processing by primitive cryptographic transformations: shuffling (reptiiaiop) - using cube shuffling blocks ( blocks of ReptiyaZO); substitution (zyB5iyshiop) - using substitution blocks (5-blocks); functional operations of cyclic shift and addition according to module 2 (ZPSHAOm) - with the help of appropriate devices. At the same time, the bit blocks of the information sequence are presented in the form of three-dimensional matrices (cubes) and as a 5-block form a variable three-dimensional matrix of substitutions, which is constructed by obtaining the multiplicative inverse element x" over the extended finite Galois field CE(25) and by performing the affine transformation y-M .x"--B8 over the primitive Galois binary field CE(2), while as a matrix

M affine transformation uses variable inverse symmetric matrices, which are chosen

Zo according to the value of the cyclic key, and the functional operations of the cyclic shift are not fixed, but depend on the state of the key.

The disadvantages of the closest analogue are that for cryptographic transformation of information as a 5-block, a fixed substitution matrix is used, which does not allow to flexibly change the parameters of cryptographic processing and dynamically control the process of substitution of information data, while for cryptographic transformation of information, the substitution parameters are fixed. Another disadvantage is that the parameters of the cyclic shift are fixed for the cryptographic transformation of information.

The basis of a useful model is the task of creating a method of cryptographic transformation of information, which, due to the use of four three-dimensional cryptographic transformations (substitution, shuffling, cyclic shift and sliding coding), will make it possible to flexibly change the parameters of cryptographic processing and dynamically control the processes of shuffling and cyclic shift and addition by modulo 2 and sliding coding of information data in three-dimensional space, while the functional operations of shuffling and cyclic shift and addition according to modulo 2 and sliding coding are not fixed, but depend on the state of the key, and iterative processing by primitive cryptographic transformations occurs in the following sequence: substitution (with !yB5iysiop), shuffling (reptiiaiyop), functional operations of cyclic shift and addition modulo 2 (ZPIYNOMm), functional operations of sliding coding (51IiaSoavye).

The task is solved by the fact that in the method of cryptographic transformation of information, which consists in the fact that the information sequence is presented in the form of bit blocks, which are subject to iterative processing by primitive cryptographic transformations: shuffling (reptiiyaop) - with the help of blocks of shuffling cubes (P-blocks); substitution (5!irviyshiop) - using substitution blocks (5-blocks); functional operations of cyclic shift and addition modulo 2 (ZNSHNOmM) - with the help of appropriate devices, functional operations of sliding coding (bi4Sode) - with the help of mixed Gray codes, according to a useful model, bit blocks of the information sequence are presented in the form of three-dimensional matrices (cubes), as a 5-block form a variable three-dimensional substitution matrix, which is constructed by obtaining the multiplicative inverse element x! over the extended finite Galois field CE(28) and by performing the y-M.x"-B affine transformation over the primitive binary Galois field CE(2), while variable inverse symmetric matrices are used as the matrix M of the affine transformation, which are chosen according to the value of the cyclic key, the functional operations of shuffling and cyclic shift and addition modulo 2 of sliding coding are not fixed, but depend on the state of the key, iterative processing by primitive cryptographic transformations occurs in the following sequence: substitution (5!yB5iysiop), shuffling (reptiiaiyop), functional operations of cyclic shift and addition according to module 2 (ZPyVoOm), functional operations of sliding coding (51iaSode).

The technical result of the useful model consists in obtaining the ability to flexibly change the parameters of cryptographic processing of information data and dynamically manage the processes of mixing and cyclic shift and addition by module 2, and sliding coding.

The method of cryptographic transformation of information is implemented by the fact that the information sequence is presented in the form of 256-bit blocks, which are subject to iterative processing by primitive cryptographic transformations: shuffling (regtshiiyaaiyop) - with the help of cube shuffling blocks (P-blocks); substitution (5!Ir5iyshiop) - using blocks of substitutions (5-blocks); functional operations of cyclic shift and addition according to module 2 (ZPSHAoOMM) - with the help of appropriate devices; functional operations of sliding coding (BidSoade) - using mixed Gray codes. As a 5-block, there is a variable matrix of substitutions, which is constructed by obtaining the multiplicative inverse element x" over the extended finite Galois field CE(23) and by performing the affine transformation (1) over the primitive binary Galois field CE(2), at the same time as a symmetric matrix M affine transformation uses variable inverse symmetric matrices, which are chosen according to the value of the cyclic key, the functional operations of shuffling and cyclic shift and addition modulo 2 and sliding coding are not fixed, but depend on the state of the key, iterative processing with primitive cryptographic transformations occurs in the following sequence: substitution (5!y05iiishiop), shuffling (reptiiyaiop), functional operations of cyclic shift and addition modulo 2 (5PyNAoOm), functional operations of sliding coding (51IiaSoavye).

The cyclic key is generated from the encryption key using the key generation algorithm. The length of the cyclic key is equal to the length of the block. Cycle keys are generated from the encryption key using key expansion. The extended key is a linear array of 4-byte words. That is, at each iteration of the cryptographic transformation, a corresponding symmetric matrix M is used, which can be selected from a large set of inverse matrices with the help of a cyclic 4-byte key. This makes it possible to flexibly change the shuffling matrix in the process of cryptographic transformation and dynamically control the process of shuffling, substitution, cyclic shift and sliding coding of information data.

Depending on the state of the round key, the parameter of shuffling, substitution, cyclic shift and sliding coding is selected by adding modulo 2 all bytes of the key, setting 1 in the lower digit of the result of addition (to form an odd value) and getting rid of the higher digit of the result of addition (remains 7 with 8 significant bits). The final value determines the amount of shift in the current round.

Thus, due to the use of variable inverse symmetric matrices and a variable (dependent on the round key) substitution function, it is possible to apply dynamically changing substitution matrices and different values of sliding coding as a 5-block at each iteration of the cryptographic transformation of information, which makes it possible to flexibly change the parameters of cryptographic processing and dynamically control the processes of mixing and cyclic shift and addition by modulo 2 and sliding coding of information data in three-dimensional space.

Sources of information: 1. "RIR5 ROV 46-3" GEOEVAI IMEOVMATIOM RAVOSEBBIMIa ZTAMOANVOV ROVI ISATIOM. RATA EMSAMRTIOM ZTAMOANVO (OE5) 1999 OKiobeg 25, radez 26. pEruLlymly.emeguzres.sot/MIZT/MIZT-RIRB/dompioai. рыр"зрес-РИРЗ РОВ 46-3.030171. рай 2. Patent of Ukraine for a utility model Me99696, IPC (p:09С 11/00 (2015.01). Method of cryptographic transformation of information / Biletskyi A.Ya., Navrotskyi D.O.; applicant and the patent owner is the National Aviation University. - Mo c201404060; application 04/16/2014; published 06/25/2015, Mo 12-5 p.

Claims (1)

USEFUL MODEL FORMULA A method of cryptographic transformation of information, which consists in the fact that the information sequence is presented in the form of bit blocks, which are subject to iterative processing by primitive cryptographic transformations: shuffling (repetition) - with the help of bo blocks, shuffling cubes (P-blocks); substitution (zibv5iyshiop) - using substitution blocks (5 blocks); functional operations of cyclic shift and addition by modulo 2 (ZPSHNVOmU) - using appropriate devices, functional operations of sliding coding (5iIiySode) - using mixed Gray codes, which is distinguished by the fact that the bit blocks of the information sequence are presented in the form of three-dimensional matrices (cubes), as a 5-block form a variable three-dimensional matrix of substitutions, which is constructed by obtaining the multiplicative inverse element x" over the extended finite Galois field CE(25) and by performing the affine transformation y-M.x"--8 over the primitive binary Galois field CE(2) , while variable inverse symmetric matrices are used as the matrix M of the affine transformation, which are chosen according to the value of the cyclic key, the functional operations of shuffling and cyclic shift and addition modulo 2 and sliding coding are not fixed, but depend on the state of the key, iterative processing with primitive cryptographic transformations occurs in the following sequence: substitution (5YiB5iyshi op), shuffling (reptiiaiop), functional operations of cyclic shift and addition modulo 2 (ZPShNOm/), functional operations of sliding coding (51iiiaSode).