220 results about "Modular exponentiation" patented technology

A side channel attack utilizes information gained from the physical implementation of a cryptosystem. Software and hardware-based systems and methods for preventing side channel attacks are presented. Cryptographic hardware may introduce dummy operations to compensate for conditional math operations in certain functions such as modular exponentiation. Cryptographic hardware may also introduce random stalls of the data path to introduce alterations in the power profile for the operation. A cryptographic function may be mapped to a micro code sequence having a plurality of instructions. Firmware in the cryptosystem may alter the micro code sequence by altering the order of instructions, add dummy operations in the micro code sequence, break the micro code sequence into multiple sub micro code sequences and/or change the register location for source and destination operands used in the sequence. These alterations are designed to randomly change the timing and power profile of the requested function.

A cryptographic system and method for encrypting input data, in which an example system includes a table calculator configured to calculate table values composed of one of scalar multiplication values by Elliptic Curve (EC) operation, or exponentiation values by modular exponentiation operation, based on input data and the number of a portion of bits of each of secret keys. The table calculator may output one of scalar multiplication values or exponentiation values corresponding to a window that includes given bits of each of the secret keys from among the calculated table values. A logic circuit may be configured to output encrypted data by accumulating the output scalar multiplication values or by performing involution on the output exponentiation values.

The invention relates to information technology security and microprocessor design. Aiming at increasing RSA (Ron Rivest, Adi Shamirh and LenAdleman) modular multiplication operation speed and improving RSA encryption and decryption performances, the invention provides the technical scheme as follows: a method for processing an RSA password based on a residue number system comprises the followingsteps of performs encryption and decryption operations by using an RSA algorithm and performing large-number modular exponentiation of the RSA algorithm by using an L-R (Left-Right) binary scanning modular power algorithm; an improved Montgomery algorithm is specifically as follows: 1024-bit large numbers with are expressed as numbers under the residue number system, namely two sets of 33 32-bit decimal numbers and one 32-bit number expressed under a redundancy base; an expression process is a mould solving process; the decomposed 32-bit decimal numbers respectively participate in 32-bit modular multiplication, modular multiplication accumulation and modular addition operation independently; furthermore, 32-bit data performs parallel execution operation without dependence; and the method disclosed by the invention is mainly applicable for the information technology security and microprocessor design.

A computer hardware implemented cryptography method computes a modular exponentiation, M:=C^d (mod p·q) upon a message data value C using a Chinese Remainder Theorem (CRT) based technique. To secure against cryptanalysis,, the private key moduli p and q are transformed by multiplication with a generated random value s, so that p′:=p·s and q′:=q·s. The CRT steps of the modular exponentiation are applied using the transformed moduli p′ and q′ to obtain a random intermediate message data value M′. A final reduction of M′ modulo p·q yields the final message data value M. Values needed for the computation are loaded into data storage and accessed as needed by electronic processing hardware.

A pre-computation and dual-pass modular operation approach to implement encryption protocols efficiently in electronic integrated circuits is disclosed. An encrypted electronic message is received and another electronic message generated based on the encryption protocol. Two passes of Montgomery's method are used for a modular operation that is associated with the encryption protocol along with pre-computation of a constant based on a modulus. The modular operation may be a modular multiplication or a modular exponentiation. Modular arithmetic may be performed using the residue number system (RNS) and two RNS bases with conversions between the two RNS bases. A minimal number of register files are used for the computations along with an array of multiplier circuits and an array of modular reduction circuits. The approach described allows for high throughput for large encryption keys with a relatively small number of logical gates.

The invention discloses a method suitable for RSA modular exponentiation calculation. The method comprises the following steps of: 1, acquiring a random number R'; 2, calculating a modular inverse value R of R' to an RSA modulus n, namely R=R'-1mod n; 3, averagely dividing an index into r segments, and ensuring that the length of each segment is s-bit; 4, calculating T1=M (RSA modular exponentiation base number) and Ti+1=2s.Ti, wherein i=1,2,..., n; and 5, performing RSA modular exponentiation calculation. By the quick and safe method suitable for the RSA modular exponentiation calculation, the RSA modular exponentiation calculation can be completed by taking measures of combining average segmentation of the index and base number mask, so that the cycle index in the modular exponentiation calculation is reduced, time cost required by the modular exponentiation calculation is reduced, calculation flows in various conditional branches are balanced, and random elements are added in an input part of modular exponentiation; and therefore, the modular exponentiation calculation can be carried out more quickly and safely.

A system and recording medium for securing data and methods thereof including a modular exponentiation. One embodiment includes first masking a message, second masking an exponent, and executing a modular exponentiation based at least one of the first and second maskings. Another embodiment includes first masking a message, second masking at least one exponent, executing a modular exponentiation based at least one of the first and second maskings, detecting an error, executing a modular multiplication operation based on the detection and diffusing the detected error to generate an electronic signature. Yet another embodiment includes first masking a message, second masking at least one exponent, executing a modular exponentiation based at least one of the first and second maskings, detecting an error, and generating an electronic signature based on the detected error.

The invention discloses an RSA (Rivest-Shamirh-Adleman) algorithm and an IP core, relating to the technical field of electronic information encryption and aiming to solve the technical problems of overlarge IP core area and lower computing speed of the RAS algorithm. The IP core for operating the RAS algorithm comprises an interface module, a control module, a memory module, a modular exponentiation module and a modular reduction module, wherein the control module is respectively connected with the modular reduction module, the memory module, the modular exponentiation module and the interface module; the modular reduction module is respectively connected with the modular exponentiation module and the memory module; and the memory module is respectively connected with the modular exponentiation module and the interface module. The invention has the characteristics of emphasis on small area, high performance, lowend-oriented RAS IP core, adoption of advanced encryption algorithms and proper hardware structures and demand on less addition and storage space.

The invention belongs to the technical field of information safety, and in particular relates to a lattice-based cloud storage data safety auditing method supporting data proxy uploading. The auditing method provided by the invention helps a data owner authorize a proxy signature generating data to a proxy signer and upload the proxy signature to a cloud server, and also helps a credible auditor to audit completeness of the cloud storage data. The auditing method provided by the invention achieves construction of a random mask code based on an original image sampling algorithm on the lattice, so that the credible auditor can be effectively prevented from recovering original data block information of an original signer from a data file. The credible auditor only needs to compute a linear combination with limited a computation amount instead of computing bilinear pairings with higher cost and modular exponentiation during a cloud storage data completeness verification process, so that the auditing method is very beneficial to the credible auditor in the aspect of computing efficiency. Meanwhile the method provided by the invention can effectively resist attacks of a quantum computer, and thus have very important application value in cloud computing environment of post-quantum communication security.

The disclosed technology of the present invention relates to an information processing device such as an IC card, and specifically to the overflow processing which occurs in a modular multiplication operation during crypto-processing. Such overflow processing exhibits a particular pattern of consumption current. It is the subject of the present invention to decrease the relationship between the data processing and the pattern of the consumption current. In the processing procedures for performing a modular exponentiation operation according to the 2 bit addition chain method, the modular multiplication operation to be executed is selected at random, the selected modular multiplication operation is executed for each 2 bits, the correction of the result is performed, and the result of the calculation (i.e, a corrected value or uncorrected value) is outputted.

The invention provides an ECC coprocessor, which includes a command/status register, a decoding control unit, a data register, a dual-port SRAM, a dot addition control unit, a dot multiplication control unit, a modular power control unit, a modular multiplication control unit, Modular addition/modulus subtraction control unit, basic arithmetic unit. The ECC coprocessor of the present invention realizes and provides externally the functions of large integer modular multiplication, modular addition/modulus subtraction, modular exponentiation and elliptic curve point addition/point multiplication, and the coordinates of elliptic curve points in the external interface of point addition and point multiplication operations The use of Jacobian coordinates can support external controllers to flexibly implement multiple point multiplication operations.

The invention belongs to the technical field of cyberspace security and particularly relates to a PEKS (public-key encryption with keyword search) method for lattice-based cloud stored cyphertext data under standard model. The method of the invention has no need for a random oracle so that the security of the designed PEKS method can more truly reflected; a designed cryptographic algorithm is based on assumption of LWE (learning with errors) hard problems, quantum computer attacks can be resisted effectively. The method of the invention has a need for specifying a unique cloud server to perform testing and return corresponding search results, so that no malicious servers are able to execute search test operation, and malicious server attacks are partly avoided accordingly. In addition, the algorithm can ensure that cyphertext is undistinguishable. Furthermore, in keyword cyphertext generation phase, the method of the invention needs no computing of high-overhead modular exponentiation and bilinear pairing operation, but the computing of finite linear algebraic operation, and accordingly is highly worthy of practical application in post-quantum communication environments.

Disclosed is the design and development of a new cipher called the Dragonfire Cipher. The Dragon cipher includes message authentication code and keyed random number generator. Dragonfire cipher takes this transparent method of generating S-boxes and uses them to create a cipher with keyed S-boxes. This defeats most precomputations for cryptanalysis as the S-boxes are now different between sessions.

The embodiment of the invention provides a method for realizing Paillier encryption based on an FPGA chip. In the method, a data distribution module respectively distributes a plaintext data set M, akey n and a random number set r to a confusion encryption engine, a parameter calculation module and a plurality of modular exponentiation calculation engines. And the parameter calculation module determines parameters N, RR, U0 and np required by Paillier encryption according to the key n, and distributes the key n and the parameters N, RR, U0 and np to a plurality of modular exponentiation calculation engines and confusion encryption engines. And the modular exponentiation calculation engines perform parallel modular exponentiation calculation by using the random number set r, the key n andthe parameters N, RR, U0 and np. And the obtained modular exponentiation calculation result is provided to a confusion encryption engine after aggregation processing. And the confusion encryption engine performs confusion encryption by using the aggregation processing result, the key n, the parameters N, RR, U0 and np and the plaintext data set to obtain a ciphertext data set. By utilizing the method, the calculation efficiency of the Paillier encryption algorithm can be improved by utilizing the high parallel calculation characteristic of the FPGA.

Ciphertext X and a constant C having relationships C>p and C>q with respect to secret keys p and q are input, and correction values C^−dp and C^−dq (dp=d mod (p−1), dq=d mod (q−1)) are obtained. Then, the ciphertext X is multiplied by the constant C. A remainder operation using the secret key p or q as a remainder value is conducted with respect to the multiplication result. A modular exponentiation operation based on a Chinese remainder theorem is conducted with respect to the remainder operation result, and a correction operation using a correction value C^−dp or C^−dq is conducted. Thereafter, plaintext Y before being encrypted is calculated.

The modular exponentiation function used in public key encryption and decryption systems is implemented in a standalone engine having at its core modular multiplication circuits which operate in two phases which share overlapping hardware structures. The partitioning of large arrays in the hardware structure, for multiplication and addition, into smaller structures results in a multiplier design comprising a series of nearly identical processing elements linked together in a chained fashion. As a result of the two-phase operation and the chaining together of partitioned processing elements, the overall structure is operable in a pipelined fashion to improve throughput and speed. The chained processing elements are constructed so as to provide a partitionable chain with separate parts for processing factors of the modulus. In this mode, the system is particularly useful for exploiting characteristics of the Chinese Remainder Theorem to perform rapid exponentiation operations. A checksum mechanism is also provided to insure accurate operation without impacting speed and without significantly increasing complexity. While the present disclosure is directed to a complex system which includes a number of features, the present application is particularly directed a system and method for performing modular checksum operations.

The invention discloses an RSA coprocessor for an RFID (radio frequency identification device) intelligent card chip. The RSA coprocessor comprises a main control unit for controlling the whole RSA encryption and decryption process, wherein the main control unit is connected with a storing control unit, a preprocessing unit and a modular exponentiation unit respectively through control lines; the modular exponentiation unit is connected with a subtracting processing unit through the control line; the preprocessing unit, the modular exponentiation unit and the subtracting processing unit are connected with a multiplexing logical operation unit; a storing control unit is connected with the preprocessing unit, the modular exponentiation unit and the subtracting processing unit, and connected to an intelligent card CPU (Central Processing Unit) through an external interface. The RSA coprocessor disclosed by the invention greatly improves the data processing efficiency, releases the data processing pressure of the intelligent card CPU, and meets the requirements on the efficiency and the stability of the encryption and decryption algorithm of the intelligent card chip RSA.

The subject of the disclosed technology is, when a crypto-processing is performed utilizing an information processing device buried in an IC card, etc., to decrease the relationship between the waveform of the consumption current and the contents of the crypto-processing as a countermeasure against a tamper which observes the waveform of a consumption current. A solution means is shown in the following. When a decryption processing of an RSA cryptogram is performed according to CRT, in step 608, for every unit bit block of XP a modular exponentiation calculation is performed, and the partial result of CP up to the calculated bit block is stored in a memory. In step 609, for every unit bit block of XQ a modular exponentiation calculation is performed and the partial result of CQ up to the calculated bit block is stored in a memory. In step 606, a random number is generated, and in step 607, it is decided that step 608 is to be executed or step 609 is to be executed corresponding to the value of the random number.

The modular exponentiation function used in public key encryption and decryption systems is implemented in a standalone engine having at its core modular multiplication circuits which operate in two phases which share overlapping hardware structures. The partitioning of large arrays in the hardware structure, for multiplication and addition, into smaller structures results in a multiplier design comprising a series of nearly identical processing elements linked together in a chained fashion. As a result of the two-phase operation and the chaining together of partitioned processing elements, the overall structure is operable in a pipelined fashion to improve throughput and speed. The chained processing elements are constructed so as to provide a partitionable chain with separate parts for processing factors of the modulus. In this mode, the system is particularly useful for exploiting characteristics of the Chinese Remainder Theorem to perform rapid exponentiation operations. A checksum mechanism is also provided to insure accurate operation without impacting speed and without significantly increasing complexity. While the present disclosure is directed to a complex system which includes a number of features, the present application is particularly directed to circuits and methods for carrying out modular exponentiation.

The present invention proposes a method for executing a blinded modular exponentiation, based on a window method with a window size of k bits so using 2^k pre-calculated variables (Y_i=Xⁱ mod N for i=0 to 2^k−1), on input data X of n bits to obtain output data S of n bits, S=X^d mod N, where d is the exponent of size m bits and N is the modulus of n bits, comprising the steps of: •blinding the pre-calculated variables by a blinding value Bi being a pseudo-random variable of the size of the modulus (n bits) and lower than the modulus (Y_j=Y_i×B₁ mod N for i=0 to 2^k−1) •executing the modular exponentiation with the blinded pre-calculated variables, to obtain an intermediate result (A), •unblinding the intermediate result by a unblinding value C₁=(B₁^g)⁻¹ mod N where g equals the concatenation of m/k times the value “1” coded on k bits, to obtain the output data S.