Java ECFieldFp类代码示例

import java.security.spec.ECFieldFp; //导入依赖的package包/类
private void decodeTest()
{
    EllipticCurve curve = new EllipticCurve(
            new ECFieldFp(new BigInteger("6277101735386680763835789423207666416083908700390324961279")), // q
            new BigInteger("fffffffffffffffffffffffffffffffefffffffffffffffc", 16), // a
            new BigInteger("64210519e59c80e70fa7e9ab72243049feb8deecc146b9b1", 16)); // b

    ECPoint p = ECPointUtil.decodePoint(curve, Hex.decode("03188da80eb03090f67cbf20eb43a18800f4ff0afd82ff1012"));

    if (!p.getAffineX().equals(new BigInteger("188da80eb03090f67cbf20eb43a18800f4ff0afd82ff1012", 16)))
    {
        fail("x uncompressed incorrectly");
    }

    if (!p.getAffineY().equals(new BigInteger("7192b95ffc8da78631011ed6b24cdd573f977a11e794811", 16)))
    {
        fail("y uncompressed incorrectly");
    }
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
public static ECParameterSpec encodeECParameterSpec(EllipticCurveParameters params) {

        // Field
        final BigInteger pInt = new BigInteger(1, params.getP());
        final ECField field = new ECFieldFp(pInt);

        final BigInteger aInt = new BigInteger(1, params.getA());
        final BigInteger bInt = new BigInteger(1, params.getB());
        final EllipticCurve curve = new EllipticCurve(field, aInt, bInt);

        // Fixed Point G
        final BigInteger xInt = new BigInteger(1, params.getX());
        final BigInteger yInt = new BigInteger(1, params.getY());
        final ECPoint g = new ECPoint(xInt, yInt);

        // Order N
        final BigInteger nInt = new BigInteger(1, params.getN());

        return new ECParameterSpec(curve, g, nInt, params.getH());
    }
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
private static BigInteger[] addPointsA(BigInteger[] P1, BigInteger[] P2,
    ECParameterSpec params) {
  final BigInteger p = ((ECFieldFp) params.getCurve().getField()).getP();

  if (P2[0] == null || P2[1] == null) return P1;

  if (P1[0] == null || P1[1] == null) return P2;

  BigInteger d = (P2[1].subtract(P1[1])).multiply((P2[0].subtract(P1[0]))
      .modInverse(p));
  BigInteger[] R = new BigInteger[2];
  R[0] = d.pow(2).subtract(P1[0]).subtract(P2[0]).mod(p);
  R[1] = d.multiply(P1[0].subtract(R[0])).subtract(P1[1]).mod(p);

  return R;
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
private static ECCurve convertCurve(
    EllipticCurve ec)
{
    ECField field = ec.getField();
    BigInteger a = ec.getA();
    BigInteger b = ec.getB();

    if (field instanceof ECFieldFp)
    {
        return new ECCurve.Fp(((ECFieldFp)field).getP(), a, b);
    }
    else
    {
        throw new IllegalStateException("not implemented yet!!!");
    }
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
public static ECCurve convertCurve(
    EllipticCurve ec)
{
    ECField field = ec.getField();
    BigInteger a = ec.getA();
    BigInteger b = ec.getB();

    if (field instanceof ECFieldFp)
    {
        return new ECCurve.Fp(((ECFieldFp)field).getP(), a, b);
    }
    else
    {
        ECFieldF2m fieldF2m = (ECFieldF2m)field;
        int m = fieldF2m.getM();
        int ks[] = ECUtil.convertMidTerms(fieldF2m.getMidTermsOfReductionPolynomial());
        return new ECCurve.F2m(m, ks[0], ks[1], ks[2], a, b); 
    }
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
public static String getCurveName(ECParameterSpec spec)
    throws InvalidAlgorithmParameterException
{
    int curve_id;

    /* Ecc object doesn't need to be initialied before call */
    if (!(spec.getCurve().getField() instanceof ECFieldFp)) {
        throw new InvalidAlgorithmParameterException(
            "Currently only ECFieldFp fields supported");
    }
    ECFieldFp field = (ECFieldFp)spec.getCurve().getField();
    EllipticCurve curve = spec.getCurve();

    curve_id = wc_ecc_get_curve_id_from_params(
                field.getFieldSize(),
                field.getP().toByteArray(),
                curve.getA().toByteArray(),
                curve.getB().toByteArray(),
                spec.getOrder().toByteArray(),
                spec.getGenerator().getAffineX().toByteArray(),
                spec.getGenerator().getAffineY().toByteArray(),
                spec.getCofactor());

    return wc_ecc_get_curve_name_from_id(curve_id);
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
private static ECParameterSpec mapNonceGMWithECDH(final BigInteger nonceS,
		                                          final ECPoint sharedSecretPointH,
		                                          final ECParameterSpec params) {
	// D~ = (p, a, b, G~, n, h) where G~ = [s]G + H
	final ECPoint generator = params.getGenerator();
	final EllipticCurve curve = params.getCurve();
	final BigInteger a = curve.getA();
	final BigInteger b = curve.getB();
	final ECFieldFp field = (ECFieldFp)curve.getField();
	final BigInteger p = field.getP();
	final BigInteger order = params.getOrder();
	final int cofactor = params.getCofactor();
	final ECPoint ephemeralGenerator = add(multiply(nonceS, generator, params), sharedSecretPointH, params);
	if (!toBouncyCastleECPoint(ephemeralGenerator, params).isValid()) {
		LOGGER.warning("Se ha generado un punto invalido"); //$NON-NLS-1$
	}
	return new ECParameterSpec(new EllipticCurve(new ECFieldFp(p), a, b), ephemeralGenerator, order, cofactor);
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
private static ECParameterSpec mapNonceGMWithECDH(final BigInteger nonceS,
		                                          final ECPoint sharedSecretPointH,
		                                          final ECParameterSpec params) {
	// D~ = (p, a, b, G~, n, h) where G~ = [s]G + H
	final ECPoint generator = params.getGenerator();
	final EllipticCurve curve = params.getCurve();
	final BigInteger a = curve.getA();
	final BigInteger b = curve.getB();
	final ECFieldFp field = (ECFieldFp)curve.getField();
	final BigInteger p = field.getP();
	final BigInteger order = params.getOrder();
	final int cofactor = params.getCofactor();
	final ECPoint ephemeralGenerator = add(multiply(nonceS, generator, params), sharedSecretPointH, params);
	if (!toSpongyCastleECPoint(ephemeralGenerator, params).isValid()) {
		LOGGER.warning("Se ha generado un punto invalido"); //$NON-NLS-1$
	}
	return new ECParameterSpec(new EllipticCurve(new ECFieldFp(p), a, b), ephemeralGenerator, order, cofactor);
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
public static ECParameterSpec CfcaCurve() {
	// 素数P
	BigInteger p = new BigInteger("FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFF", 16);

	// 基于素数P的有限域
	ECFieldFp gfp = new ECFieldFp(p);

	// 在有限域上的椭圆曲线y2 = x3 + ax + b
	EllipticCurve ellipticCurve = new EllipticCurve(gfp,
			new BigInteger("FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFC", 16),
			new BigInteger("28E9FA9E9D9F5E344D5A9E4BCF6509A7F39789F515AB8F92DDBCBD414D940E93", 16));

	// 基点G
	ECPoint G = new ECPoint(new BigInteger("32C4AE2C1F1981195F9904466A39C9948FE30BBFF2660BE1715A4589334C74C7", 16),
			new BigInteger("BC3736A2F4F6779C59BDCEE36B692153D0A9877CC62A474002DF32E52139F0A0", 16));

	// G的阶
	BigInteger n = new BigInteger("FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFF7203DF6B21C6052B53BBF40939D54123", 16);

	// 设置基点
	ECParameterSpec ecParameterSpec = new ECParameterSpec(ellipticCurve, G, n, 1);
	return ecParameterSpec;
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
ECParameterSpec getECParameterSpec() {
    final String curveName = NativeCrypto.EC_GROUP_get_curve_name(groupCtx);

    final byte[][] curveParams = NativeCrypto.EC_GROUP_get_curve(groupCtx);
    final BigInteger p = new BigInteger(curveParams[0]);
    final BigInteger a = new BigInteger(curveParams[1]);
    final BigInteger b = new BigInteger(curveParams[2]);

    final ECField field = new ECFieldFp(p);

    final EllipticCurve curve = new EllipticCurve(field, a, b);

    final OpenSSLECPointContext generatorCtx = new OpenSSLECPointContext(this,
            new NativeRef.EC_POINT(NativeCrypto.EC_GROUP_get_generator(groupCtx)));
    final ECPoint generator = generatorCtx.getECPoint();

    final BigInteger order = new BigInteger(NativeCrypto.EC_GROUP_get_order(groupCtx));
    final BigInteger cofactor = new BigInteger(NativeCrypto.EC_GROUP_get_cofactor(groupCtx));

    ECParameterSpec spec = new ECParameterSpec(curve, generator, order, cofactor.intValue());
    Platform.setCurveName(spec, curveName);
    return spec;
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
/**
 * Returns this key as ECPublicKeySpec or null if the key cannot be represented as
 * ECPublicKeySpec. The later happens for example if the order of cofactor are not positive.
 */
public ECPublicKeySpec getSpec() {
  try {
    ECFieldFp fp = new ECFieldFp(p);
    EllipticCurve curve = new EllipticCurve(fp, a, b);
    ECPoint g = new ECPoint(gx, gy);
    // ECParameterSpec requires that the cofactor h is specified.
    if (h == null) {
      return null;
    }
    ECParameterSpec params = new ECParameterSpec(curve, g, n, h);
    ECPoint pubPoint = new ECPoint(pubx, puby);
    ECPublicKeySpec pub = new ECPublicKeySpec(pubPoint, params);
    return pub;
  } catch (Exception ex) {
    System.out.println(comment + " throws " + ex.toString());
    return null;
  }
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
public static ECParameterSpec getNistCurveSpec(
    String decimalP, String decimalN, String hexB, String hexGX, String hexGY) {
  final BigInteger p = new BigInteger(decimalP);
  final BigInteger n = new BigInteger(decimalN);
  final BigInteger three = new BigInteger("3");
  final BigInteger a = p.subtract(three);
  final BigInteger b = new BigInteger(hexB, 16);
  final BigInteger gx = new BigInteger(hexGX, 16);
  final BigInteger gy = new BigInteger(hexGY, 16);
  final int h = 1;
  ECFieldFp fp = new ECFieldFp(p);
  java.security.spec.EllipticCurve curveSpec = new java.security.spec.EllipticCurve(fp, a, b);
  ECPoint g = new ECPoint(gx, gy);
  ECParameterSpec ecSpec = new ECParameterSpec(curveSpec, g, n, h);
  return ecSpec;
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
public static ECParameterSpec getBrainpoolP256r1Params() {
  BigInteger p =
      new BigInteger("A9FB57DBA1EEA9BC3E660A909D838D726E3BF623D52620282013481D1F6E5377", 16);
  BigInteger a =
      new BigInteger("7D5A0975FC2C3057EEF67530417AFFE7FB8055C126DC5C6CE94A4B44F330B5D9", 16);
  BigInteger b =
      new BigInteger("26DC5C6CE94A4B44F330B5D9BBD77CBF958416295CF7E1CE6BCCDC18FF8C07B6", 16);
  BigInteger x =
      new BigInteger("8BD2AEB9CB7E57CB2C4B482FFC81B7AFB9DE27E1E3BD23C23A4453BD9ACE3262", 16);
  BigInteger y =
      new BigInteger("547EF835C3DAC4FD97F8461A14611DC9C27745132DED8E545C1D54C72F046997", 16);
  BigInteger n =
      new BigInteger("A9FB57DBA1EEA9BC3E660A909D838D718C397AA3B561A6F7901E0E82974856A7", 16);
  final int h = 1;
  ECFieldFp fp = new ECFieldFp(p);
  EllipticCurve curve = new EllipticCurve(fp, a, b);
  ECPoint g = new ECPoint(x, y);
  return new ECParameterSpec(curve, g, n, h);
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
/**
 * Decompress a point
 *
 * @param x The x-coordinate of the point
 * @param bit0 true if the least significant bit of y is set.
 * @param ecParams contains the curve of the point. This must be over a prime order field.
 */
public static ECPoint getPoint(BigInteger x, boolean bit0, ECParameterSpec ecParams)
    throws GeneralSecurityException {
  EllipticCurve ec = ecParams.getCurve();
  ECField field = ec.getField();
  if (!(field instanceof ECFieldFp)) {
    throw new GeneralSecurityException("Only curves over prime order fields are supported");
  }
  BigInteger p = ((java.security.spec.ECFieldFp) field).getP();
  if (x.compareTo(BigInteger.ZERO) == -1 || x.compareTo(p) != -1) {
    throw new GeneralSecurityException("x is out of range");
  }
  // Compute rhs == x^3 + a x + b (mod p)
  BigInteger rhs = x.multiply(x).add(ec.getA()).multiply(x).add(ec.getB()).mod(p);
  BigInteger y = modSqrt(rhs, p);
  if (bit0 != y.testBit(0)) {
    y = p.subtract(y).mod(p);
  }
  return new ECPoint(x, y);
}
 

import java.security.spec.ECFieldFp; //导入依赖的package包/类
private static ECCurve convertCurve(
    EllipticCurve ec, BigInteger order, int coFactor)
{
    ECField field = ec.getField();
    BigInteger a = ec.getA();
    BigInteger b = ec.getB();

    if (field instanceof ECFieldFp)
    {
        return new ECCurve.Fp(((ECFieldFp)field).getP(), a, b, order, BigInteger.valueOf(coFactor));
    }
    else
    {
        throw new IllegalStateException("not implemented yet!!!");
    }
}