public ECDomainParameters(
ECCurve curve,
ECPoint g,
BigInteger n)
: this(curve, g, n, BigInteger.One)
{
}
public X9ECParameters(
ECCurve curve,
ECPoint g,
BigInteger n)
: this(curve, g, n, BigInteger.One, null)
{
}
public ECDomainParameters(
ECCurve curve,
ECPoint g,
BigInteger n,
BigInteger h)
: this(curve, g, n, h, null)
{
}
public static ECPoint ImportPoint(ECCurve c, ECPoint p)
{
ECCurve cp = p.Curve;
if (!c.Equals(cp))
throw new ArgumentException("Point must be on the same curve");
return c.ImportPoint(p);
}
public X9Curve(
X9FieldID fieldID,
Asn1Sequence seq)
{
if (fieldID == null)
throw new ArgumentNullException("fieldID");
if (seq == null)
throw new ArgumentNullException("seq");
this.fieldIdentifier = fieldID.Identifier;
if (fieldIdentifier.Equals(X9ObjectIdentifiers.PrimeField))
{
BigInteger q = ((DerInteger) fieldID.Parameters).Value;
X9FieldElement x9A = new X9FieldElement(q, (Asn1OctetString) seq[0]);
X9FieldElement x9B = new X9FieldElement(q, (Asn1OctetString) seq[1]);
curve = new FpCurve(q, x9A.Value.ToBigInteger(), x9B.Value.ToBigInteger());
}
else
{
if (fieldIdentifier.Equals(X9ObjectIdentifiers.CharacteristicTwoField))
{
// Characteristic two field
DerSequence parameters = (DerSequence)fieldID.Parameters;
int m = ((DerInteger)parameters[0]).Value.IntValue;
DerObjectIdentifier representation
= (DerObjectIdentifier)parameters[1];
int k1 = 0;
int k2 = 0;
int k3 = 0;
if (representation.Equals(X9ObjectIdentifiers.TPBasis))
{
// Trinomial basis representation
k1 = ((DerInteger)parameters[2]).Value.IntValue;
}
else
{
// Pentanomial basis representation
DerSequence pentanomial = (DerSequence) parameters[2];
k1 = ((DerInteger) pentanomial[0]).Value.IntValue;
k2 = ((DerInteger) pentanomial[1]).Value.IntValue;
k3 = ((DerInteger) pentanomial[2]).Value.IntValue;
}
X9FieldElement x9A = new X9FieldElement(m, k1, k2, k3, (Asn1OctetString)seq[0]);
X9FieldElement x9B = new X9FieldElement(m, k1, k2, k3, (Asn1OctetString)seq[1]);
// TODO Is it possible to get the order (n) and cofactor(h) too?
curve = new F2mCurve(m, k1, k2, k3, x9A.Value.ToBigInteger(), x9B.Value.ToBigInteger());
}
}
if (seq.Count == 3)
{
seed = ((DerBitString) seq[2]).GetBytes();
}
}
public X9ECParameters(
Asn1Sequence seq)
{
if (!(seq[0] is DerInteger)
|| !((DerInteger) seq[0]).Value.Equals(BigInteger.One))
{
throw new ArgumentException("bad version in X9ECParameters");
}
X9Curve x9c = null;
if (seq[2] is X9Curve)
{
x9c = (X9Curve) seq[2];
}
else
{
x9c = new X9Curve(
new X9FieldID(
(Asn1Sequence) seq[1]),
(Asn1Sequence) seq[2]);
}
this.curve = x9c.Curve;
if (seq[3] is X9ECPoint)
{
this.g = ((X9ECPoint) seq[3]).Point;
}
else
{
this.g = new X9ECPoint(curve, (Asn1OctetString) seq[3]).Point;
}
this.n = ((DerInteger) seq[4]).Value;
this.seed = x9c.GetSeed();
if (seq.Count == 6)
{
this.h = ((DerInteger) seq[5]).Value;
}
}
public ECDomainParameters(
ECCurve curve,
ECPoint g,
BigInteger n,
BigInteger h,
byte[] seed)
{
if (curve == null)
throw new ArgumentNullException("curve");
if (g == null)
throw new ArgumentNullException("g");
if (n == null)
throw new ArgumentNullException("n");
if (h == null)
throw new ArgumentNullException("h");
this.curve = curve;
this.g = g.Normalize();
this.n = n;
this.h = h;
this.seed = Arrays.Clone(seed);
}
public X9Curve(
ECCurve curve,
byte[] seed)
{
if (curve == null)
throw new ArgumentNullException("curve");
this.curve = curve;
this.seed = Arrays.Clone(seed);
if (ECAlgorithms.IsFpCurve(curve))
{
this.fieldIdentifier = X9ObjectIdentifiers.PrimeField;
}
else if (ECAlgorithms.IsF2mCurve(curve))
{
this.fieldIdentifier = X9ObjectIdentifiers.CharacteristicTwoField;
}
else
{
throw new ArgumentException("This type of ECCurve is not implemented");
}
}
internal F2mPoint(ECCurve curve, ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, bool withCompression)
: base(curve, x, y, zs, withCompression)
{
}
public F2mPoint(
ECCurve curve)
: this(curve, null, null)
{
}
/**
* @param curve base curve
* @param x x point
* @param y y point
* @param withCompression true if encode with point compression.
*/
public F2mPoint(
ECCurve curve,
ECFieldElement x,
ECFieldElement y,
bool withCompression)
: base(curve, x, y, withCompression)
{
if ((x == null) != (y == null))
{
throw new ArgumentException("Exactly one of the field elements is null");
}
if (x != null)
{
// Check if x and y are elements of the same field
F2mFieldElement.CheckFieldElements(x, y);
// Check if x and a are elements of the same field
if (curve != null)
{
F2mFieldElement.CheckFieldElements(x, curve.A);
}
}
}
/**
* @param curve base curve
* @param x x point
* @param y y point
*/
public F2mPoint(
ECCurve curve,
ECFieldElement x,
ECFieldElement y)
: this(curve, x, y, false)
{
}
protected internal ECPointBase(ECCurve curve, ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, bool withCompression)
: base(curve, x, y, zs, withCompression)
{
}
protected static ECFieldElement[] GetInitialZCoords(ECCurve curve)
{
// Cope with null curve, most commonly used by implicitlyCa
int coord = null == curve ? ECCurve.COORD_AFFINE : curve.CoordinateSystem;
switch (coord)
{
case ECCurve.COORD_AFFINE:
case ECCurve.COORD_LAMBDA_AFFINE:
return EMPTY_ZS;
default:
break;
}
ECFieldElement one = curve.FromBigInteger(BigInteger.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.A };
default:
throw new ArgumentException("unknown coordinate system");
}
}
protected ECPoint(ECCurve curve, ECFieldElement x, ECFieldElement y, bool withCompression)
: this(curve, x, y, GetInitialZCoords(curve), withCompression)
{
}
internal Config(ECCurve outer, int coord, ECEndomorphism endomorphism, ECMultiplier multiplier)
{
this.outer = outer;
this.coord = coord;
this.endomorphism = endomorphism;
this.multiplier = multiplier;
}
private static ECCurve ConfigureCurve(ECCurve curve)
{
return curve;
}
public static bool IsF2mCurve(ECCurve c)
{
IFiniteField field = c.Field;
return field.Dimension > 1 && field.Characteristic.Equals(BigInteger.Two)
&& field is IPolynomialExtensionField;
}
public static int GetByteLength(ECCurve c)
{
return (c.FieldSize + 7) / 8;
}
public X9Curve(
ECCurve curve)
: this(curve, null)
{
}
public X9ECParameters(
ECCurve curve,
ECPoint g,
BigInteger n,
BigInteger h,
byte[] seed)
{
this.curve = curve;
this.g = g.Normalize();
this.n = n;
this.h = h;
this.seed = seed;
if (ECAlgorithms.IsFpCurve(curve))
{
this.fieldID = new X9FieldID(curve.Field.Characteristic);
}
else if (ECAlgorithms.IsF2mCurve(curve))
{
IPolynomialExtensionField field = (IPolynomialExtensionField)curve.Field;
int[] exponents = field.MinimalPolynomial.GetExponentsPresent();
if (exponents.Length == 3)
{
this.fieldID = new X9FieldID(exponents[2], exponents[1]);
}
else if (exponents.Length == 5)
{
this.fieldID = new X9FieldID(exponents[4], exponents[1], exponents[2], exponents[3]);
}
else
{
throw new ArgumentException("Only trinomial and pentomial curves are supported");
}
}
else
{
throw new ArgumentException("'curve' is of an unsupported type");
}
}
/**
* Create a point that encodes with or without point compression.
*
* @param curve the curve to use
* @param x affine x co-ordinate
* @param y affine y co-ordinate
* @param withCompression if true encode with point compression
*/
public FpPoint(ECCurve curve, ECFieldElement x, ECFieldElement y, bool withCompression)
: base(curve, x, y, withCompression)
{
if ((x == null) != (y == null))
throw new ArgumentException("Exactly one of the field elements is null");
}
protected AbstractF2mPoint(ECCurve curve, ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, bool withCompression)
: base(curve, x, y, zs, withCompression)
{
}
public static bool IsFpCurve(ECCurve c)
{
return c.Field.Dimension == 1;
}
internal ECPoint(ECCurve curve, ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, bool withCompression)
{
this.m_curve = curve;
this.m_x = x;
this.m_y = y;
this.m_zs = zs;
this.m_withCompression = withCompression;
}
private static ECCurve ConfigureCurveGlv(ECCurve c, GlvTypeBParameters p)
{
return c.Configure().SetEndomorphism(new GlvTypeBEndomorphism(c, p)).Create();
}
public virtual bool Equals(ECCurve other)
{
if (this == other)
return true;
if (null == other)
return false;
return Field.Equals(other.Field)
&& A.ToBigInteger().Equals(other.A.ToBigInteger())
&& B.ToBigInteger().Equals(other.B.ToBigInteger());
}