ECCEGKeyGenerator.java
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	package crypto.elgamal;

	import java.math.BigInteger;
	import java.security.SecureRandom;

	import org.bouncycastle.asn1.nist.NISTNamedCurves;
	import org.bouncycastle.asn1.x9.X9ECParameters;
	import org.bouncycastle.math.ec.ECPoint;

	public class ECCEGKeyGenerator {

	private SecureRandom randGen;

	private BigInteger order;

	private X9ECParameters ecParams;

	public ECCEGKeyGenerator(String curveName) {
	this.randGen = new SecureRandom();
	this.ecParams = NISTNamedCurves.getByName(curveName);
	this.order = ecParams.getN();
	}

	/**
	*
	* @param order
	* order of the group
	* @return
	*/
	public KeyPair generateKey() {

	// generate the secret and random coefficient
	BigInteger secret = new BigInteger(order.bitLength() - 1, randGen);
	BigInteger a1 = new BigInteger(order.bitLength() - 1, randGen);

	BigInteger[] coefficients = new BigInteger[2];
	coefficients[0] = secret;
	coefficients[1] = a1;

	// generate both secret shares
	PartialSecret secretMU = new PartialSecret(PartialSecret.PART_MU, coefficients, order);
	PartialSecret secretSPU = new PartialSecret(PartialSecret.PART_SPU, coefficients, order);

	// generate public key
	ECPoint pubKey = ecParams.getG().multiply(secret);

	return new KeyPair(secretMU, secretSPU, pubKey);
	}
	}