iaik.security.ecc.math.algorithms
Class SquareRoot

java.lang.Object
  iaik.security.ecc.math.algorithms.SquareRoot

public class SquareRoot

extends java.lang.Object

Find a square root

Method Summary

static FieldElement	calcSQRT(FieldElement g) performs the squre root calculation
static java.math.BigInteger[]	lucasSeq(java.math.BigInteger p, java.math.BigInteger q, java.math.BigInteger k, java.math.BigInteger n) Generates Lucas sequences according to algorithm A.2.4 of the P1363 standard.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

calcSQRT

public static FieldElement calcSQRT(FieldElement g)
                             throws AlgorithmException

performs the squre root calculation

Parameters:

g - the already modulo reduced field element

Returns:

the square root of g or null if no such square root exists

Throws:

AlgorithmException

lucasSeq

public static java.math.BigInteger[] lucasSeq(java.math.BigInteger p,
                                              java.math.BigInteger q,
                                              java.math.BigInteger k,
                                              java.math.BigInteger n)
                                       throws AlgorithmException

Generates Lucas sequences according to algorithm A.2.4 of the P1363 standard.

Parameters:

p - the parameter p of the lucas sequence

q - the parameter q of the lucas sequence

k - the index k of the sequence

n - the modulus

Returns:

Vk mod n and Q^(k/2) mod n

Throws:

AlgorithmException