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This is a collection of JAVA libraries that implement Unbound cryptographic classes for JAVA provider, PKCS11 wrapper, cryptoki, and advapi

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package com.unbound.common.crypto.ec;

import com.unbound.common.crypto.ec.math.UInt;

import java.math.BigInteger;
import java.security.spec.ECPoint;

public final class Point
{
  final Curve curve;
  final int[] x = new int[Curve.MAX_LEN];
  final int[] y = new int[Curve.MAX_LEN];
  final int[] z = new int[Curve.MAX_LEN];

  Point()
  {
    this.curve = null;
  }

  Point(Curve curve)
  {
    this.curve = curve;
  }

  public Point(Curve curve, BigInteger xx, BigInteger yy)
  {
    this.curve = curve;
    int[] x = curve.alloc(); UInt.fromBigInteger(curve.length, x, xx);
    int[] y = curve.alloc(); UInt.fromBigInteger(curve.length, y, yy);
    curve.init(this, x, y);
  }

  Point(Curve curve, int[] x, int[] y)
  {
    this.curve = curve;
    curve.init(this, x, y);
  }

  BigInteger getX()
  {
    int[] temp = curve.alloc();
    curve.getCoord(this, temp, null);
    return UInt.toBigInteger(curve.length, temp);
  }

  BigInteger getY()
  {
    int[] temp = curve.alloc();
    curve.getCoord(this, null, temp);
    return UInt.toBigInteger(curve.length, temp);
  }

  byte[] toOct()
  {
    int l = toOct(null, 0);
    byte[] out = new byte[l];
    toOct(out, 0);
    return out;
  }

  byte[] toCompressedOct()
  {
    int l = toCompressedOct(null, 0);
    byte[] out = new byte[l];
    toCompressedOct(out, 0);
    return out;
  }

  int toOct(byte[] out, int offset)
  {
    int bytes = curve.getBytes();
    if (out!=null) curve.toOct(this, out, offset);
    return 1 + bytes*2;
  }

  int toCompressedOct(byte[] out, int offset)
  {
    int bytes = curve.getBytes();
    if (out!=null) curve.toCompressedOct(this, out, offset);
    return 1 + bytes;
  }

  boolean isInfinity()
  {
    return 0 != UInt.isZero(curve.length, z);
  }

  boolean isOnCurve()
  {
    return curve.isOnCurve(this);
  }

  @Override
  public boolean equals(Object other)
  {
    if (this==other) return true;
    if (other==null) return false;
    if ((other instanceof Point))
    {
      return curve.equ(this, ((Point)other));
    }
    if (other instanceof ECPoint)
    {
      return curve.equ(this, (ECPoint)other);
    }
    return false;
  }

  public Point dbl()
  {
    Point r = new Point(curve);
    curve.dbl(r, this, null);
    return r;
  }

  public Point add(Point p)
  {
    Point r = new Point(curve);
    curve.add(r, this, p, null);
    return r;
  }

  public Point mul(BigInteger xx)
  {
    int[] x = curve.alloc();
    UInt.fromBigInteger(curve.length, x, xx);
    return mul(x);
  }

  Point mul(int[] x)
  {
    Point r = new Point(curve);
    curve.mul(r, this, x);
    return r;
  }

  static void copy(Point r, Point p)
  {
    System.arraycopy(p.x, 0, r.x, 0, Curve.MAX_LEN);
    System.arraycopy(p.y, 0, r.y, 0, Curve.MAX_LEN);
    System.arraycopy(p.z, 0, r.z, 0, Curve.MAX_LEN);
  }
}