摘要:
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.
摘要:
A method and apparatus to square an element A when a defining polynomial of a finite field GF(2n) is expressed as f ( x ) = x n + ∑ i = 1 i x k 1 + 1 , and the element A contained in the finite field is expressed as A−(a0,a1,a2 . . . ,an−1)∈GF(2n). The method determines coefficients mi, Iij, V0, Vij, and V such that the coefficient mi satisfies a predetermined condition with respect to ki when 1≦i≦t is a natural number, Iij depends on n, ki, and j when 2≦j≦mi, V0 and Vij of n bits, respectively, depend on n, Iij, and ki, and obtains the coefficient V with respect to mi according to the following formula V i = V i2 ⊕ V i3 ⊕ … ⊕ V im , V = V 0 ⊕ ∑ m 1 ≠ 0 V i determines a coefficient si according to ki and n and cyclically shifts the coefficient V by si; performing an XOR operation on the cyclically shifted coefficient V and the element A; and rewires a result of the XOR operation in a predetermined order and outputs results of the squaring.
摘要:
A countermeasure method in an electronic component uses a public key cryptographic algorithm on a specific elliptic curve E on a body IK. An exponential computation of Qnulld.P type is carried out, where P and Q are points of the specific elliptic curve E, and d is a predetermined number. A non-null random number u is selected which is an element of the finite body IK, to define randomly an isomorphic elliptic curve Eunull. Co-ordinates of a point Pnull on the isomorphic elliptic curve Eunull are calculated which are an image of the point P. An exponentiation algorithm is applied to the point image Pnull on the isomorphic elliptic curve Eunull, to obtain a resulting point Qnull. Co-ordinates on the specific elliptic curve E of point Q, which is a pre-image of the resulting point Qnull, are then computed.
摘要:
An error correction code circuit with reduced hardware complexity is positioned inside a microprocessor. The microprocessor has a Galois field multiplier for performing a Galois field multiplication on data processed by the error correction code circuit. The error correction code circuit has a first register for storing an input data, a plurality of calculation units, a third register for storing an output data corresponding to the input data, and a controller for controlling operation of the error correction code circuit. Each calculation unit has a Galois field adder, and a second register electrically connected to the Galois field adder. The controller transmits data of each calculation unit to the same Galois field multiplier for a corresponding Galois field multiplication, and the result outputted by the Galois field multiplier is transmitted back to the error correction code circuit.
摘要:
A multiply execution unit that is operable to generate the integer product and the XOR product of a multiplicand and a multiplier. The multiply execution unit includes a summing circuit for summing a plurality of partial products. The partial products may be Booth encoded. The summing circuit can generate an integer sum of the plurality of partial products and can generate an XOR sum of the plurality of partial products. The summing circuit includes a first plurality of full adders. The first plurality of full adders each has three inputs, a carry output, and a sum output. The sum outputs of the first plurality of full adders are independent of the value of any carry output in the summing circuit. The summing circuit also includes a second plurality of full adders. The second plurality of full adders each has three inputs, a carry output, and a sum output. The XOR sum is dependent upon at least one of the sum outputs of the first plurality of full adders but is independent of the sum outputs of the second plurality of full adders. The integer sum is dependent upon the sum outputs of at least one of the first plurality of full adders and is also dependent on at least one of the sum outputs of the second plurality of full adders.
摘要:
Parallel modulo arithmetic calculations are carried out on a device adapted to perform bitwise logical operations by storing the numbers to be operated upon in a vector form, and performing arithmetical operations on multiple numbers in parallel. The invention finds particular application in cryptosystems, as well as in other fields.
摘要:
A Galois field arithmetic unit includes a Galois field multiplier section and a Galois field adder section. The Galois field multiplier section includes a plurality of Galois field multiplier arrays that perform a Galois field multiplication by multiplying, in accordance with a generating polynomial, a 1st operand and a 2nd operand. The bit size of the 1st and 2nd operands correspond to the bit size of a processor data path, where each of the Galois field multiplier arrays performs a portion of the Galois field multiplication by multiplying, in accordance with a corresponding portion of the generating polynomial, corresponding portions of the 1st and 2nd operands. The bit size of the corresponding portions of the 1st and 2nd operands corresponds to a symbol size of symbols of a coding scheme being implemented by the corresponding processor.
摘要:
An objective is to obtain a Jacobian group element adder that can calculate addition in a Jacobian group of a Cab curve at a high speed, and can enhance practicality of the Cab curve. An algebraic curve parameter file A 10, and Groebner bases I1 and I2 of ideals of a coordinate ring of an algebraic curve designated by this file A are input into an ideal composition section 11 to perform arithmetic of producing a Groebner basis J of an ideal product of the ideal generated by I1 and ideal generated by I2. In a first ideal reduction section 12, arithmetic is performed of producing a Groebner basis J* of an ideal that is smallest in a monomial order designated by the file A among ideals equivalent to an inverse ideal of an ideal that J in the coordinate ring of the algebraic curve designated by the file A generates. In a second ideal reduction section 13, arithmetic is performed of producing a Groebner basis J** of a ideal that is smallest in the monomial order designated by the file A among ideals equivalent to an inverse ideal of an ideal that this J* generates to output it.
摘要:
A multiplier for obtaining the product of elements in a Galois Field. The multiplier performs the multiplication of two n-bit elements, A(an-1, an-2, . . . , a3, a2, a1, a0) and B(bn-1, bn-2, . . . , b3, b2, b1, b0) in the Galois Field to yield the product C(cn-1, cn-2, . . . , c3, c2, c1, c0), wherein n≧1 ai(i=0˜n-1), bj(j=0˜n-1), and ck(k=O˜n-1) are all binary bits. The multiplier includes: an AND planer, for performing an AND logic operation of every bit ai in A(an-1, an-2, . . . , a3, a2, a1, a0) and every bit bj in B(bn-1, bn-2, . . . , b3, b2, b1, b0) to obtain (an-1bn-1, an-1bn-2, . . . , an-1b0, an-2bn-1, an-2bn-2, . . . , an-2b0, a0bn-1, a0bn-2, . . . , a0b0); and an XOR planer, for performing an XOR logic operation of the output from the AND planer to obtain C(cn-1, cn-2, . . . , c3, c2, c1, c0).
摘要:
The improved AES processing method provides an efficient alternative to both Mips intensive multiplication and to conventional table lookup, used to multiply terms over a Galois field (GF). The improved method takes advantage of the fact that in the GF, any non zero element X can be represented by a power of a primitive element P. The improved method thereby results in a 2 by 256 table. The log base P of the terms being multiplied are looked up and summed, and the anti-log of the sum is looked up in the same table.