org.spongycastle.math.ec.ECCurve.getA()方法的使用及代码示例

x33g5p2x  于2022-01-19 转载在 其他  
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本文整理了Java中org.spongycastle.math.ec.ECCurve.getA()方法的一些代码示例，展示了ECCurve.getA()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。ECCurve.getA()方法的具体详情如下：
包路径：org.spongycastle.math.ec.ECCurve
类名称：ECCurve
方法名：getA

ECCurve.getA介绍

暂无

代码示例

代码示例来源：origin: com.madgag.spongycastle/core

protected static ECFieldElement[] getInitialZCoords(ECCurve curve)
{
  // Cope with null curve, most commonly used by implicitlyCa
  int coord = null == curve ? ECCurve.COORD_AFFINE : curve.getCoordinateSystem();
  switch (coord)
  {
  case ECCurve.COORD_AFFINE:
  case ECCurve.COORD_LAMBDA_AFFINE:
    return EMPTY_ZS;
  default:
    break;
  }
  ECFieldElement one = curve.fromBigInteger(ECConstants.ONE);
  switch (coord)
  {
  case ECCurve.COORD_HOMOGENEOUS:
  case ECCurve.COORD_JACOBIAN:
  case ECCurve.COORD_LAMBDA_PROJECTIVE:
    return new ECFieldElement[]{ one };
  case ECCurve.COORD_JACOBIAN_CHUDNOVSKY:
    return new ECFieldElement[]{ one, one, one };
  case ECCurve.COORD_JACOBIAN_MODIFIED:
    return new ECFieldElement[]{ one, curve.getA() };
  default:
    throw new IllegalArgumentException("unknown coordinate system");
  }
}

代码示例来源：origin: com.madgag/sc-light-jdk15on

/**
 * @param curve base curve
 * @param x x point
 * @param y y point
 * @param withCompression true if encode with point compression.
 */
public F2m(ECCurve curve, ECFieldElement x, ECFieldElement y, boolean withCompression)
{
  super(curve, x, y);
  if ((x != null && y == null) || (x == null && y != null))
  {
    throw new IllegalArgumentException("Exactly one of the field elements is null");
  }
  
  if (x != null)
  {
    // Check if x and y are elements of the same field
    ECFieldElement.F2m.checkFieldElements(this.x, this.y);
    // Check if x and a are elements of the same field
    if (curve != null)
    {
      ECFieldElement.F2m.checkFieldElements(this.x, this.curve.getA());
    }
  }
  
  this.withCompression = withCompression;
}

代码示例来源：origin: com.madgag.spongycastle/core

public boolean equals(ECCurve other)
{
  return this == other
    || (null != other
      && getField().equals(other.getField())
      && getA().toBigInteger().equals(other.getA().toBigInteger())
      && getB().toBigInteger().equals(other.getB().toBigInteger()));
}

代码示例来源：origin: com.madgag.spongycastle/core

public int hashCode() 
{
  return getField().hashCode()
    ^ Integers.rotateLeft(getA().toBigInteger().hashCode(), 8)
    ^ Integers.rotateLeft(getB().toBigInteger().hashCode(), 16);
}

代码示例来源：origin: com.madgag.spongycastle/core

public static void discoverEndomorphisms(X9ECParameters x9)
{
  if (x9 == null)
  {
    throw new NullPointerException("x9");
  }
  ECCurve c = x9.getCurve();
  if (ECAlgorithms.isFpCurve(c))
  {
    BigInteger characteristic = c.getField().getCharacteristic();
    if (c.getA().isZero() && characteristic.mod(ECConstants.THREE).equals(ECConstants.ONE))
    {
      System.out.println("Curve has a 'GLV Type B' endomorphism with these parameters:");
      printGLVTypeBParameters(x9);
    }
  }
}

代码示例来源：origin: com.madgag.spongycastle/core

private static void discoverEndomorphisms(String curveName)
{
  X9ECParameters x9 = ECNamedCurveTable.getByName(curveName);
  if (x9 == null)
  {
    System.err.println("Unknown curve: " + curveName);
    return;
  }
  ECCurve c = x9.getCurve();
  if (ECAlgorithms.isFpCurve(c))
  {
    BigInteger characteristic = c.getField().getCharacteristic();
    if (c.getA().isZero() && characteristic.mod(ECConstants.THREE).equals(ECConstants.ONE))
    {
      System.out.println("Curve '" + curveName + "' has a 'GLV Type B' endomorphism with these parameters:");
      printGLVTypeBParameters(x9);
    }
  }
}

代码示例来源：origin: com.madgag.spongycastle/prov

public static EllipticCurve convertCurve(
  ECCurve curve, 
  byte[]  seed)
{
  ECField field = convertField(curve.getField());
  BigInteger a = curve.getA().toBigInteger(), b = curve.getB().toBigInteger();
  // TODO: the Sun EC implementation doesn't currently handle the seed properly
  // so at the moment it's set to null. Should probably look at making this configurable
  return new EllipticCurve(field, a, b, null);
}

代码示例来源：origin: com.madgag.spongycastle/prov

private static EllipticCurve convertCurve(
  ECCurve  curve,
  byte[]   seed)
{
  ECField field = convertField(curve.getField());
  BigInteger a = curve.getA().toBigInteger(), b = curve.getB().toBigInteger();
  return new EllipticCurve(field, a, b, seed);
}

代码示例来源：origin: com.madgag.spongycastle/bcpkix-jdk15on

private static EllipticCurve convertCurve(
  ECCurve curve)
{
  ECField field = convertField(curve.getField());
  BigInteger a = curve.getA().toBigInteger(), b = curve.getB().toBigInteger();
  // TODO: the Sun EC implementation doesn't currently handle the seed properly
  // so at the moment it's set to null. Should probably look at making this configurable
  return new EllipticCurve(field, a, b, null);
}

代码示例来源：origin: com.madgag.spongycastle/pkix

private static EllipticCurve convertCurve(
  ECCurve curve)
{
  ECField field = convertField(curve.getField());
  BigInteger a = curve.getA().toBigInteger(), b = curve.getB().toBigInteger();
  // TODO: the Sun EC implementation doesn't currently handle the seed properly
  // so at the moment it's set to null. Should probably look at making this configurable
  return new EllipticCurve(field, a, b, null);
}

代码示例来源：origin: com.madgag.spongycastle/core

protected Curve25519FieldElement calculateJacobianModifiedW(Curve25519FieldElement Z, int[] ZSquared)
{
  Curve25519FieldElement a4 = (Curve25519FieldElement)this.getCurve().getA();
  if (Z.isOne())
  {
    return a4;
  }
  Curve25519FieldElement W = new Curve25519FieldElement();
  if (ZSquared == null)
  {
    ZSquared = W.x;
    Curve25519Field.square(Z.x, ZSquared);
  }
  Curve25519Field.square(ZSquared, W.x);
  Curve25519Field.multiply(W.x, a4.x, W.x);
  return W;
}

代码示例来源：origin: es.gob.afirma.jmulticard/jmulticard

private static BigInteger computeAffineY(final BigInteger affineX, final ECParameterSpec params) {
  final ECCurve bcCurve = toSpongyCastleECCurve(params);
  final ECFieldElement a = bcCurve.getA();
  final ECFieldElement b = bcCurve.getB();
  final ECFieldElement x = bcCurve.fromBigInteger(affineX);
  final ECFieldElement y = x.multiply(x).add(a).multiply(x).add(b).sqrt();
  return y.toBigInteger();
}

代码示例来源：origin: com.madgag/scprov-jdk15on

public static EllipticCurve convertCurve(
  ECCurve curve, 
  byte[]  seed)
{
  // TODO: the Sun EC implementation doesn't currently handle the seed properly
  // so at the moment it's set to null. Should probably look at making this configurable
  if (curve instanceof ECCurve.Fp)
  {
    return new EllipticCurve(new ECFieldFp(((ECCurve.Fp)curve).getQ()), curve.getA().toBigInteger(), curve.getB().toBigInteger(), null);
  }
  else
  {
    ECCurve.F2m curveF2m = (ECCurve.F2m)curve;
    int ks[];
    
    if (curveF2m.isTrinomial())
    {
      ks = new int[] { curveF2m.getK1() };
      
      return new EllipticCurve(new ECFieldF2m(curveF2m.getM(), ks), curve.getA().toBigInteger(), curve.getB().toBigInteger(), null);
    }
    else
    {
      ks = new int[] { curveF2m.getK3(), curveF2m.getK2(), curveF2m.getK1() };
      
      return new EllipticCurve(new ECFieldF2m(curveF2m.getM(), ks), curve.getA().toBigInteger(), curve.getB().toBigInteger(), null);
    } 
  }
}

代码示例来源：origin: com.madgag/scprov-jdk15on

private static EllipticCurve convertCurve(
  ECCurve  curve,
  byte[]   seed)
{
  if (curve instanceof ECCurve.Fp)
  {
    return new EllipticCurve(new ECFieldFp(((ECCurve.Fp)curve).getQ()), curve.getA().toBigInteger(), curve.getB().toBigInteger(), seed);
  }
  else
  {
    ECCurve.F2m curveF2m = (ECCurve.F2m)curve;
    int ks[];
    
    if (curveF2m.isTrinomial())
    {
      ks = new int[] { curveF2m.getK1() };
      
      return new EllipticCurve(new ECFieldF2m(curveF2m.getM(), ks), curve.getA().toBigInteger(), curve.getB().toBigInteger(), seed);
    }
    else
    {
      ks = new int[] { curveF2m.getK3(), curveF2m.getK2(), curveF2m.getK1() };
      return new EllipticCurve(new ECFieldF2m(curveF2m.getM(), ks), curve.getA().toBigInteger(), curve.getB().toBigInteger(), seed);
    } 
  }
}

代码示例来源：origin: com.madgag.spongycastle/prov

public static String generateKeyFingerprint(ECPoint publicPoint, org.spongycastle.jce.spec.ECParameterSpec spec)
  {
    ECCurve curve = spec.getCurve();
    ECPoint g = spec.getG();

    if (curve != null)
    {
      return new Fingerprint(Arrays.concatenate(publicPoint.getEncoded(false), curve.getA().getEncoded(), curve.getB().getEncoded(), g.getEncoded(false))).toString();
    }

    return new Fingerprint(publicPoint.getEncoded(false)).toString();
  }
}

代码示例来源：origin: com.madgag/sc-light-jdk15on

public ECPoint twice()
{
  if (this.isInfinity()) 
  {
    // Twice identity element (point at infinity) is identity
    return this;
  }
  if (this.x.toBigInteger().signum() == 0) 
  {
    // if x1 == 0, then (x1, y1) == (x1, x1 + y1)
    // and hence this = -this and thus 2(x1, y1) == infinity
    return this.curve.getInfinity();
  }
  ECFieldElement.F2m lambda
    = (ECFieldElement.F2m)this.x.add(this.y.divide(this.x));
  ECFieldElement.F2m x3
    = (ECFieldElement.F2m)lambda.square().add(lambda).
      add(this.curve.getA());
  ECFieldElement ONE = this.curve.fromBigInteger(ECConstants.ONE);
  ECFieldElement.F2m y3
    = (ECFieldElement.F2m)this.x.square().add(
      x3.multiply(lambda.add(ONE)));
  return new ECPoint.F2m(this.curve, x3, y3, withCompression);
}

代码示例来源：origin: com.madgag.spongycastle/core

v.add(new X9FieldElement(curve.getA()).toASN1Primitive());
v.add(new X9FieldElement(curve.getB()).toASN1Primitive());
v.add(new X9FieldElement(curve.getA()).toASN1Primitive());
v.add(new X9FieldElement(curve.getB()).toASN1Primitive());

代码示例来源：origin: com.madgag.spongycastle/core

protected ECFieldElement calculateJacobianModifiedW(ECFieldElement Z, ECFieldElement ZSquared)
{
  ECFieldElement a4 = this.getCurve().getA();
  if (a4.isZero() || Z.isOne())
  {
    return a4;
  }
  if (ZSquared == null)
  {
    ZSquared = Z.square();
  }
  ECFieldElement W = ZSquared.square();
  ECFieldElement a4Neg = a4.negate();
  if (a4Neg.bitLength() < a4.bitLength())
  {
    W = W.multiply(a4Neg).negate();
  }
  else
  {
    W = W.multiply(a4);
  }
  return W;
}

代码示例来源：origin: com.madgag.spongycastle/core

private byte[] getZ(Digest digest)
{
  addUserID(digest, userID);
  addFieldElement(digest, ecParams.getCurve().getA());
  addFieldElement(digest, ecParams.getCurve().getB());
  addFieldElement(digest, ecParams.getG().getAffineXCoord());
  addFieldElement(digest, ecParams.getG().getAffineYCoord());
  addFieldElement(digest, pubPoint.getAffineXCoord());
  addFieldElement(digest, pubPoint.getAffineYCoord());
  byte[] rv = new byte[digest.getDigestSize()];
  digest.doFinal(rv, 0);
  return rv;
}

代码示例来源：origin: com.madgag.spongycastle/core

private byte[] getZ(Digest digest, byte[] userID, ECPoint pubPoint)
{
  addUserID(digest, userID);
  addFieldElement(digest, ecParams.getCurve().getA());
  addFieldElement(digest, ecParams.getCurve().getB());
  addFieldElement(digest, ecParams.getG().getAffineXCoord());
  addFieldElement(digest, ecParams.getG().getAffineYCoord());
  addFieldElement(digest, pubPoint.getAffineXCoord());
  addFieldElement(digest, pubPoint.getAffineYCoord());
  byte[] rv = new byte[digest.getDigestSize()];
  digest.doFinal(rv, 0);
  return rv;
}

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