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package org.bouncycastle.math.ec.custom.sec;
import java.math.BigInteger;
import org.bouncycastle.math.ec.ECConstants;
import org.bouncycastle.math.ec.ECCurve;
import org.bouncycastle.math.ec.ECFieldElement;
import org.bouncycastle.math.ec.ECMultiplier;
import org.bouncycastle.math.ec.ECPoint;
import org.bouncycastle.math.ec.GLVMultiplier;
import org.bouncycastle.math.ec.endo.GLVTypeBEndomorphism;
import org.bouncycastle.math.ec.endo.GLVTypeBParameters;
import org.bouncycastle.math.field.FiniteFields;
import org.bouncycastle.util.encoders.Hex;
public class SecP224K1Curve extends ECCurve
{
public static final BigInteger q = new BigInteger(1,
Hex.decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFE56D"));
private static final int SECP224K1_DEFAULT_COORDS = COORD_JACOBIAN;
protected SecP224K1Point infinity;
public SecP224K1Curve()
{
super(FiniteFields.getPrimeField(q));
this.infinity = new SecP224K1Point(this, null, null);
this.a = fromBigInteger(ECConstants.ZERO);
this.b = fromBigInteger(BigInteger.valueOf(5));
this.order = new BigInteger(1, Hex.decode("010000000000000000000000000001DCE8D2EC6184CAF0A971769FB1F7"));
this.cofactor = BigInteger.valueOf(1);
this.coord = SECP224K1_DEFAULT_COORDS;
}
protected ECCurve cloneCurve()
{
return new SecP224K1Curve();
}
public boolean supportsCoordinateSystem(int coord)
{
switch (coord)
{
case COORD_JACOBIAN:
return true;
default:
return false;
}
}
protected ECMultiplier createDefaultMultiplier()
{
GLVTypeBParameters p = new GLVTypeBParameters(
fromBigInteger(new BigInteger("fe0e87005b4e83761908c5131d552a850b3f58b749c37cf5b84d6768", 16)),
new BigInteger("60dcd2104c4cbc0be6eeefc2bdd610739ec34e317f9b33046c9e4788", 16),
new BigInteger[]{
new BigInteger("6b8cf07d4ca75c88957d9d670591", 16),
new BigInteger("-b8adf1378a6eb73409fa6c9c637d", 16) },
new BigInteger[]{
new BigInteger("1243ae1b4d71613bc9f780a03690e", 16),
new BigInteger("6b8cf07d4ca75c88957d9d670591", 16) },
new BigInteger("35c6783ea653ae444abeceb382c82", 16),
new BigInteger("5c56f89bc5375b9a04fd364e31bdd", 16),
227);
return new GLVMultiplier(this, new GLVTypeBEndomorphism(p));
}
public BigInteger getQ()
{
return q;
}
public int getFieldSize()
{
return q.bitLength();
}
public ECFieldElement fromBigInteger(BigInteger x)
{
return new SecP224K1FieldElement(x);
}
protected ECPoint createRawPoint(ECFieldElement x, ECFieldElement y, boolean withCompression)
{
return new SecP224K1Point(this, x, y, withCompression);
}
protected ECPoint createRawPoint(ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, boolean withCompression)
{
return new SecP224K1Point(this, x, y, zs, withCompression);
}
protected ECPoint decompressPoint(int yTilde, BigInteger X1)
{
ECFieldElement x = fromBigInteger(X1);
ECFieldElement alpha = x.square().multiply(x).add(getB());
ECFieldElement beta = alpha.sqrt();
//
// if we can't find a sqrt we haven't got a point on the
// curve - run!
//
if (beta == null)
{
throw new RuntimeException("Invalid point compression");
}
if (beta.testBitZero() != (yTilde == 1))
{
// Use the other root
beta = beta.negate();
}
return new SecP224K1Point(this, x, beta, true);
}
public ECPoint getInfinity()
{
return infinity;
}
}
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