DoubleAddMultiplier.cs
611 Bytes
namespace Org.BouncyCastle.Math.EC.Multiplier
{
public class DoubleAddMultiplier
: AbstractECMultiplier
{
/**
* Joye's double-add algorithm.
*/
protected override ECPoint MultiplyPositive(ECPoint p, BigInteger k)
{
ECPoint[] R = new ECPoint[]{ p.Curve.Infinity, p };
int n = k.BitLength;
for (int i = 0; i < n; ++i)
{
int b = k.TestBit(i) ? 1 : 0;
int bp = 1 - b;
R[bp] = R[bp].TwicePlus(R[b]);
}
return R[0];
}
}
}