/// <summary>
/// Creates a round 1 (zero-knowledge proof) DTO to send to the partner participant.
/// </summary>
public ECJpakeRound1 CreateRound1ToSend()
{
Contract.Requires(ProtocolState < State.Round1Created, "Round 1 payload already created.");
BigInteger x1 = BigInteger.CreateRandomInRange(BigInteger.One, _domain.N.Subtract(BigInteger.One),
EntropySupply);
_x2 = BigInteger.CreateRandomInRange(BigInteger.One, _domain.N.Subtract(BigInteger.One), EntropySupply);
_gx1 = BasePointMultiplier.Multiply(_domain.G, x1);
_gx2 = BasePointMultiplier.Multiply(_domain.G, _x2);
ECPoint V1, V2;
BigInteger r1, r2;
CreateZeroKnowledgeProof(_domain.G, x1, _gx1, ParticipantId, out V1, out r1);
CreateZeroKnowledgeProof(_domain.G, _x2, _gx2, ParticipantId, out V2, out r2);
var dto = new ECJpakeRound1 {
ParticipantId = ParticipantId,
GX1 = _gx1.GetEncoded(),
X1V = V1.GetEncoded(),
X1R = r1.ToByteArray(),
GX2 = _gx2.GetEncoded(),
X2V = V2.GetEncoded(),
X2R = r2.ToByteArray()
};
ProtocolState = State.Round1Created;
return(dto);
}