298 results about "S-box" patented technology

An advanced encryption standard (AES) engine with real time S-box generation includes a Galois field multiplier system in a first mode responsive to a first data block for generating an AES selection (S-box) function by executing the multiplicative increase in GF¹(2^m) and applying an affine over GF(2) transformation to obtain a subbyte transformation; and a shift register system for transforming the subbyte transformation to obtain a shift row transformation; the Galois field multiplier system is responsive in a second mode to the shift row transformation to obtain a mix column transformation and add a round key for generating in real time an advanced encryption standard cipher function of the first data block.

A cryptographic method and related implements the Rijndael—AES encryption standard. In one improvement, the decryption round keys are generated on a round by round basis from the final Nk round keys saved from a previous encryption key scheduling operation. Latency and memory requirements are thereby minimized. S-boxes for the AES key generation and cipher operation itself, may be implemented multiple times in different ways with different power signatures, with a pseudo-random selection of the pathway for the different bytes to be substituted. The premix operation occurs simultaneously with the generation of first round keys, and a dummy circuit with substantially identical timing as the real premix circuitry adds power consumption noise to the premix.

A hardware cryptographic engine implementing an Advanced Encryption Standard (AES) algorithm is disclosed. The hardware cryptographic engine comprises a plurality of modules corresponding to rounds of AES. Each of the plurality of modules comprises an S-BOX computing a multiplicative inverse of each element in an input vector over GF(2⁸) using an operation over GF(((2²)²)²), and replacing each element of the input vector with a substitute element obtained using a result of the operation.

Methods and systems for implementing a switch box (S-box) in a cryptographic application are described. An input to the S-box is converted from a Galois field representation GF(N²) to a Galois subfield representation GF(N)². The input is converted using a generating polynomial of the form x²+Ax+B, where A and B are elements in GF(N) and where A has a value other than unity. The multiplicative inverse of the Galois subfield representation GF(N)² is determined. The multiplicative inverse is converted back to the Galois field representation GF(N²). An affine transformation of the multiplicative inverse is then performed.

An encryption apparatus for generating a ciphertext block from a plaintext block is disclosed. A selector selects at random one mask random number from a plurality of random numbers generated by a random number generator. A mask processing unit executes mask processing of a plaintext block by using the mask random number selected by the selector. A storage unit stores a first table representing an initial S-box. A converter converts the first table into a second table representing a deformed S-box on the basis of the mask random number selected by the selector. An encryption unit generates a ciphertext block by shuffling the mask-processed plaintext block using the second table.

There are disclosed an extended key generator, encryption/decryption unit, and storage medium, in which as each of key transform functions, a transform process is done by an S box (substitution table) on the basis of a first key obtained from the inputted key, and an adder computes a corresponding one of extended keys on the basis of a value obtained by shifting the transformed result of the S box to the left, and a second key obtained from the inputted key.

The invention discloses an application method of a Hamming distance model on SM4 cryptographic algorithm lateral information channel energy analysis and based on S box input. The application method is characterized in that the Hamming distance model is established by selecting an S box or a round function as an attacking point in the process that the SM4 cryptographic algorithm lateral information channel energy analysis is carried out, the input of the S box is used as an initial state v1 of the Hamming distance model, the output of the S box is used as subsequent state v2 of the Hamming distance (HD (v1, v2)) model when the S box is attacked, and the output / input of the round function is used as the subsequent state v2 of the Hamming distance (HD (v1, v2)) model when the round function is attacked. The method can be applied to CPA / DPA lateral information channel energy analysis of the SM4 cryptographic algorithm. Correlation between a correct guess secret key and energy information is improved, and validity and success rate of the analysis are enhanced.

Systems and methods for implementing Advanced Encryption Standard (AES) are disclosed herein. Aspects of the method may comprise storing 256 bytes of data. A non-zero byte portion of the 256 bytes of data may be replaced with multiplicative inverse bytes in a Galois field GF(256) and the replaced inverse bytes may be affine transformed over GF (2). The affine transformed bytes may be affine inverse transformed, and the affine inverse transformed bytes may be multiplicatively inversed over GF(256). The affine transformation over GF(2) may be determined as a matrix multiplication and addition of (1 1 0 0 0 1 1 0). If the 256 bytes comprise a zero byte, the zero byte from the 256 bytes of data may be mapped to the zero byte portion of the 256 bytes of data.

The invention discloses an application of selecting round key XOR input to perform side-channel power analysis of an SM4 cryptographic algorithm. The application is characterized in that in the process of the side-channel power analysis of the SM4 cryptographic algorithm, S boxes or round functions are selected to serve as attack points to establish a Hamming distance (HD) model, the round key XOR input is taken as a preceding state v1 of the HD model, and when the S boxes are attacked, the subsequent state v2 of the HD (v1, v2) model is S box output; and when the round functions are attacked, the subsequent state v2 of the HD (v1, v2) model is output/input of the round functions. The method can be applied to the side-channel power analysis of a CPA (correlation power analysis) and DPA (differential power analysis) of the SM4 cryptographic algorithm. With the adoption of the method, the correlation between a right guessing secret key and a power message is improved, the effectiveness of the analysis is enhanced, and the success rate is increased.

The invention relates to an encryption method for network and information security; the adopted packet length and key length are 128 bits, and a 128-bit system parameter is added; encryption algorithm comprises a plurality of rounds of round transform iteration consisting of mixed layers and diffusion layers, wherein the last round is incomplete round transformation, and the incomplete round transformation consists of the mixed layer; the mixed layer comprises key plus, S box portfolio transform and system parameter minus; the S box portfolio transform comprises 8-input 8-output reversible S box transform and inverse S box transform in the same number which are output by parity exchange; the diffusion layer can construct linear transformation with a reversible re-model polynomial matrix; an encryption round key is generated by an encryption key through encryption round transformation; and decryption algorithm is the inverse transformation of encryption algorithm. The encryption methodfor network and information security has the advantages of high diffusion speed, good security strength, hardware resource saving, and very high speed when being realized by hardware and on a software platform.

The invention provides a block cipher encryption and decryption method belonging to the field of data encryption and decryption. The algorithm of the invention designs a symmetric encryption structure, especially the S-box design in the invention can configure S transformation required for encryption and S inverse transformation required for decryption without additional circuit resources, thereby being beneficial to the implementation of an encryption/decryption integrated hardware circuit and consuming fewer area resources compared with the AES (advanced encryption standard) encryption/decryption integrated circuit. The complicated S box structure of the algorithm can resist the traditional known attack methods. In case of a small number of encryption rounds (three rounds), a high encryption speed can be provided, and decryption can be carried out at the same speed by using the same encryption and decryption hardware. The algorithm is especially suitable for realizing an ASIC (application specific integrated circuit), and can realize an ASIC chip based on the encryption and decryption special-purpose algorithm. Besides, the invention can be also used for the design of IP cores on FPGA (field programmable gate array). Compared with the AES algorithm, the invention consumes fewer resources on FPGA and has higher speed.

There is provided a highly secure cryptographic processing apparatus and method where an analysis difficulty is increased. In a Feistel type common key block encrypting process in which an SPN type F function having a nonlinear conversion section and a linear conversion section is repeatedly executed a plurality of rounds. The linear conversion process of an F function corresponding to each of the plurality of rounds is performed as a linear conversion process which employs an MDS (Maximum Distance Separable) matrix, and a linear conversion process is carried out which employs a different MDS matrix at least at each of consecutive odd number rounds and consecutive even number rounds. This structure makes it possible to increase the minimum number (a robustness index against a differential attack in common key block encryption) of the active S box in the entire encrypting function.

The invention discloses a multimode reconfigurable encryption method based on an advanced encryption standard (AES) encryption algorithm. In the method, five operating modes are provided for a user to select, and an all-random S box generation way and a biased random S box generation way are provided. The method comprises the following steps of: judging whether the operating mode and an S box selected by the user are rational or not; if the selected operating mode and the selected S box are irrational, prompting the user to perform reselection; if the selected operating mode and the selected S box are rational, further calculating the smallest encryption round number according to the differential uniformity and nonlinearity of the generated S box, and determining a final encryption round number according to the requirements of the user; selecting a source file for an encryption or decryption operation; and finally storing the encrypted or decrypted data file, and providing the encrypted or decrypted data file for the user to view. By the method, side channel attacks possibly on encryption realized by adopting hardware are effectively avoided, and an operating way of the reconfigurable encryption method is optimized; the method is applied to the configuration of a set of reconfigurable software encryption system, and the reconfiguration and integration of block ciphers into the same software system; and convenience is brought to operations and management.

An encryption device eliminates data contention and minimizes area by accessing twice data for a given time by using a memory device of two times faster access time. The encryption device for performing encryption of plain text blocks using data encryption standard algorithm, wherein the encryption device includes an initial permutation unit, a data encryption unit having n-stage (n is an even number) pipeline structure using a first clock, a second clock and a third clock, and an inverse initial permutation unit, the encryption device includes: a multiplexer for selecting one of n/3 48-bit inputs; 8 S-Boxes, each for receiving 6-bit address among the selected 48-bit and outputting 4-bit data; a demultiplexer for distributing 32-bit data from the S-Boxes to n/3 outputs; and a controller for control the multiplexer and the demultiplexer with a fourth clock and a fifth clock, wherein the fourth and the fifth clock are faster than the first, the second and the third clocks by n/3 times.

The described system and method provide for an encryption and authentication technique that achieves enhanced integrity verification through assured error-propagation using a multistage sequence of pseudorandom permutations. The method generates intermediate data-dependent cryptographic variables at each stage, which are systematically combined into feedback loops. The encryption technique also generates an authentication tag with minimal post processing that is the size of the state. The size of the state is dependent on the number of pseudorandom permutations and the size of the LFSR. The authentication tag provides a unique mapping to the plaintext for any number of plaintext blocks that is less than or equal the size of the state. In addition to being a stand alone encryption algorithm, the disclosed technique is applicable to any mode that uses pseudorandom permutations such as, key dependent lookup tables, S-Boxes, and block ciphers such as RC5, TEA, and AES.

A plurality of S-boxes is masked by one masking inverse table. Therefore, the computation cost and the use amount of the RAM necessary for masking at the time of a masking operation for defending a differential power analysis attack in a SEED encryption algorithm can be effectively reduced.

The invention discloses a second-order side channel energy analysis method for an SM4 algorithm of a simple mask. To achieve mask protection for the SM4 algorithm with the output of four S boxes carrying the same mask value, the method comprises the steps of (1) acquiring energy traces and establishing a sampling energy consumption matrix; (2) preprocessing the energy consumption matrix in the previous step; (3) selecting attack points to conduct CPA or DPA to obtain rki, 0; (4) re-selecting an S-box operation part and following the steps (2) and (3) to obtain rki, u through analysis; and (5) carrying out the steps (2), (3) and (4) on previous/next four rounds to obtain a round key and obtaining an initial key through a key inverse expansion operation. The technical scheme of the invention innovatively provides the new second-order energy analysis method, develops a new situation of SM4 cryptographic algorithm attack, extends the side channel power analysis method for the SM4 algorithm, and can fully and effectively conducts side channel energy analysis on the SM4 cryptographic algorithm; and the method of the technical scheme is highly practical for common mask protection measures.

The invention discloses a method and a table look-up device for encrypting and decrypting data by using a symmetric cryptographic algorithm. The method comprises the following steps of: determining all types of S boxes required to be used when the S boxes are required to be used for table look-up in the symmetric cryptographic algorithm; determining the total amount Ni of the S boxes of each type, and when Ni is more than 1, determining that the S boxes of the type satisfy a multiplexing condition; and when the data are encrypted and decrypted by using the symmetric cryptographic algorithm, multiplexing the S boxes of at least one type satisfying the multiplexing condition. By the method and the device, occupation of the symmetric cryptographic algorithm on hardware resources can be reduced under the condition that the hardware resources are relatively constrained.

The invention provides an 8*8 S box applicable to hardware realization and a circuit realization method thereof. The S box is compounded by using an inversion operation on a finite field GF (((22)2)2) and affine transformation of GF (2)8 and has stronger nonlinearity, difference transmission probability, snowslide performance, algebra complexity and other cryptological properties. Compared with other Galois fields comprising 28 elements, the field GF (((22)2)2) selected by the invention can reduce the complexity of the inversion operation, and the selection of polynomials generated by various levels of field extension further reduces the expense of subfield operations. The invention also provides a hardware realization mode of the S box, the entire calculation process of the S box can be fully converted into the operations of XOR, AND and negation of bits, and the hardware realization mode can be realized by using a simple logic gate circuit. The entire process does not require table lookup, so that the overall realization expense of hardware is reduced.

The present invention discloses a mask S box, a packet key calculation unit, an apparatus and corresponding construction method. The mask S box comprises an input module, an address mapping processing module, and an output module. The input module receives and uses a random number and input data masked by the random number as two inputs of the mask S box. The address mapping processing module performs one-to-one mapping on the two inputs and corresponding storage addresses in a memory of the mask S box. The output module performs linear processing on the random number by using a linear equation so as to obtain and uses the random number after linear conversion as one output of the mask S box. The storage address is obtained after the random number undergone linear conversion masks the output of the original S box, and is used as another output of the mask S box. The mask S box is safe, and further, the mask S box is easy to implement, is low in power consumption and small in area, and is optimized and expanded to realize the anti-high order DPA encryption device.

A logistics distribution bill generating method based on a two-dimension code and an encryption technology includes the following steps that A1, required basic information of an original express distribution bill is obtained, and an express bill number is automatically generated; A2, the symmetric encryption algorithm AES algorithm is adopted for encrypting the related information of the original express distribution bill, and the process includes the steps that (1), 128-bit data are grouped; (2), xor calculation of an and expansion secrete key is performed; (3), S box transformation is performed; (4), row transformation is performed; (5), column transformation is performed; (6), xor is performed in the and expansion secrete key; (7), S box transformation is performed; (8), row transformation is performed; (9), xor is performed on the and expansion secrete key; (10), the 128-bit data are output; A3, a two-dimension code express distribution bill is generated through a two-dimension code generator. The distribution efficiency and safety degree of logistics can be improved.

The invention provides a method and a device for implementing AES (Advanced Encryption Standard) enciphering and deciphering. The method comprises the following steps: loading data to be enciphered/deciphered to a register; outputting the data to be enciphered/deciphered to an S box multiplex unit for Nr round operation, wherein Nr is determined by the key length; performing enciphering/deciphering S box operation by the S box multiplex unit on data sent by the register according to an enciphering/deciphering control signal; performing enciphering/deciphering column mixing operation and round key addition operation on the data output by the S box multiplex unit, and caching an operation result to the register; and in the Nrth round operation, performing round key addition operation on output of the S box multiplex unit and then outputting an result to complete enciphering/deciphering. Thus, the method and the device for implementing AES enciphering and deciphering can cache the results of enciphering and deciphering round operations by using the same register, and realize S box and inverse S box operations by using the same logic, and thereby achieving the aim of reducing chip area and power consumption.

The invention discloses a cipher device adopting a Feistel-PG structure and an encryption method. The Feistel-PG structure consists of a round function F, the round function F maps a t*k*m bit string into a t*k*m bit string, the input X is mapped into U through linear conversion P and nonlinear conversion G, the linear conversion P is displacement based on the t*k*m bit string and is the position conversion of t*m k bit characters, the nonlinear conversion G is concatenation of t nonlinear conversions based on t*k bit string, the nonlinear conversion T is nonlinear conversion based on k*m bit string, and T converts (um-1 to u1, u0) into A (S(um-1 to u1, u0)) through S box layer and linear conversion A, wherein the S box layer is formed by m k*k s boxes through concatenation, and the linear conversion A is linear conversion based on k*m bit string. The encryption method adopting the Feistel-PG encryption structure comprises round key addition, linear conversion P and nonlinear conversion G, the output of plaintext W after the r-round iteration is used as ciphertext. Through the device and the method provided by the invention, the cipher algorithm design is more flexible, and in addition, lower realization cost can be realized at the same security intensity.