public PublicKey(ECPoint point)
{
this.IsCompressedPoint = point.IsCompressed;
this.point = point;
this.PublicKeyBytes = point.GetEncoded();
if (validatePoint() == false) throw new ArgumentException("Not a valid public key");
}
protected ECPublicBcpgKey(
DerObjectIdentifier oid,
ECPoint point)
{
this.point = new BigInteger(1, point.GetEncoded());
this.oid = oid;
}
/// <summary>
/// Computes the public key from the private key.
/// </summary>
protected override byte[] ComputePublicKey()
{
var ps = Org.BouncyCastle.Asn1.Sec.SecNamedCurves.GetByName("secp256k1");
Org.BouncyCastle.Math.EC.ECPoint point = ps.G;
Org.BouncyCastle.Math.BigInteger Db = new Org.BouncyCastle.Math.BigInteger(1, _privKey);
Org.BouncyCastle.Math.EC.ECPoint dd = point.Multiply(Db);
if (IsCompressedPoint)
{
dd = ps.Curve.CreatePoint(dd.X.ToBigInteger(), dd.Y.ToBigInteger(), true);
return(dd.GetEncoded());
}
else
{
byte[] pubaddr = new byte[65];
byte[] Y = dd.Y.ToBigInteger().ToByteArray();
Array.Copy(Y, 0, pubaddr, 64 - Y.Length + 1, Y.Length);
byte[] X = dd.X.ToBigInteger().ToByteArray();
Array.Copy(X, 0, pubaddr, 32 - X.Length + 1, X.Length);
pubaddr[0] = 4;
return(pubaddr);
}
}
/**
* @param privateKey hex string without 0x
* @return
*/
public static string GetPublicKeyFromPrivateKey(string privateKey, bool compressed)
{
BigInteger bigInteger = new BigInteger(privateKey, 16);
ECPoint point = GetPublicPointFromPrivate(bigInteger);
return(ByteUtil.ByteArrayToHexString(point.GetEncoded(compressed)));
}
public static byte GetRecoveryId(byte[] sigR, byte[] sigS, byte[] message, byte[] publicKey)
{
//ECNamedCurveParameterSpec spec = ECNamedCurveTable.getParameterSpec("secp256k1");
X9ECParameters spec = ECNamedCurveTable.GetByName("secp256k1");
BigInteger pointN = spec.N;
for (int recoveryId = 0; recoveryId < 2; recoveryId++)
{
try
{
BigInteger pointX = new BigInteger(1, sigR);
byte[] compEnc =
X9IntegerConverter.IntegerToBytes(pointX, 1 + X9IntegerConverter.GetByteLength(spec.Curve));
compEnc[0] = (byte)((recoveryId & 1) == 1 ? 0x03 : 0x02);
ECPoint pointR = spec.Curve.DecodePoint(compEnc);
if (!pointR.Multiply(pointN).IsInfinity)
{
continue;
}
BigInteger pointE = new BigInteger(1, message);
BigInteger pointEInv = BigInteger.Zero.Subtract(pointE).Mod(pointN);
BigInteger pointRInv = new BigInteger(1, sigR).ModInverse(pointN);
BigInteger srInv = pointRInv.Multiply(new BigInteger(1, sigS)).Mod(pointN);
BigInteger pointEInvRInv = pointRInv.Multiply(pointEInv).Mod(pointN);
ECPoint pointQ = ECAlgorithms.SumOfTwoMultiplies(spec.G, pointEInvRInv, pointR, srInv);
byte[] pointQBytes = pointQ.GetEncoded(false);
bool matchedKeys = true;
for (int j = 0; j < publicKey.Length; j++)
{
if (pointQBytes[j] != publicKey[j])
{
matchedKeys = false;
break;
}
}
if (!matchedKeys)
{
continue;
}
return((byte)(0xFF & recoveryId));
}
catch (Exception e)
{
continue;
Console.WriteLine(" Failed: GET recoveryID");
}
}
return((byte)0xFF);
}
public static ECPoint CleanPoint(ECCurve c, ECPoint p)
{
ECCurve cp = p.Curve;
if (!c.Equals(cp))
{
throw new ArgumentException("Point must be on the same curve", "p");
}
return(c.DecodePoint(p.GetEncoded(false)));
}
//public static bool VerifySignature(AsymmetricKeyParameter pubKey, string signature, string msg)
//{
// try
// {
// byte[] msgBytes = Encoding.UTF8.GetBytes(msg);
// byte[] sigBytes = Convert.FromBase64String(signature);
// ISigner signer = SignerUtilities.GetSigner("SHA384withECDSA");
// signer.Init(false, pubKey);
// signer.BlockUpdate(msgBytes, 0, msgBytes.Length);
// return signer.VerifySignature(sigBytes);
// }
// catch (Exception exc)
// {
// Console.WriteLine("Verification failed with the error: " + exc.ToString());
// return false;
// }
//}
/// <summary>
/// NOT WORKING cause of SHA 256
/// </summary>
/// <param name="pubK"></param>
/// <returns></returns>
//public static AsymmetricKeyParameter GetPublicKeyObjectRepresentation(string pubK)
//{
// //byte[] recoveredPublic = Convert.FromBase64String(pubK);
// byte[] recoveredPublic = Base58Encoding.Decode(pubK);
// var publicKey = PublicKeyFactory.CreateKey(recoveredPublic);
// return publicKey;
//}
//public static string GetPublicKeyStringRepresentation(AsymmetricKeyParameter pubK)
//{
// SubjectPublicKeyInfo subjectPublicKeyInfo = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(pubK);
// byte[] serializedPublicBytes = subjectPublicKeyInfo.ToAsn1Object().GetDerEncoded();
// var base64 = Convert.ToBase64String(serializedPublicBytes);
// var sha256 = ComputeSha256HashB(base64);
// var result = Base58Encoding.Encode(sha256);
// return result;
//}
/// <summary>
/// Not gonna be used
/// </summary>
/// <param name="priK"></param>
/// <returns></returns>
//public static string GetPrivateKeyStringRepresentation(AsymmetricKeyParameter priK)
//{
// PrivateKeyInfo privateKeyInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(priK);
// byte[] serializedPrivateBytes = privateKeyInfo.ToAsn1Object().GetDerEncoded();
// //var result = Convert.ToBase64String(serializedPrivateBytes);
// var result = Base58Encoding.Encode(serializedPrivateBytes);
// return result;
//}
//private static string ComputeSha256Hash(string rawData)
//{
// // Create a SHA256
// using (SHA256 sha256Hash = SHA256.Create())
// {
// // ComputeHash - returns byte array
// byte[] bytes = sha256Hash.ComputeHash(Encoding.UTF8.GetBytes(rawData));
// // Convert byte array to a string
// StringBuilder builder = new StringBuilder();
// for (int i = 0; i < bytes.Length; i++)
// {
// builder.Append(bytes[i].ToString("x2"));
// }
// return builder.ToString();
// }
//}
/**
* Converts a private key into its corresponding public key.
*/
public static byte[] GetPublicKey(byte[] privateKey)
{
try
{
//ECNamedCurveParameterSpec spec = ECNamedCurveTable.getParameterSpec("secp256k1");
X9ECParameters spec = ECNamedCurveTable.GetByName("secp256k1");
ECPoint pointQ = spec.G.Multiply(new BigInteger(1, privateKey));
return(pointQ.GetEncoded(false));
}
catch (Exception e)
{
Console.WriteLine(" Failed: GET public key");
return(new byte[0]);
}
}
/**
* Recover the public key that corresponds to the private key, which signed this message.
*/
public static byte[] RecoverPublicKey(byte[] sigR, byte[] sigS, byte[] sigV, byte[] message)
{
//ECNamedCurveParameterSpec spec = ECNamedCurveTable.getParameterSpec("secp256k1");
X9ECParameters spec = ECNamedCurveTable.GetByName("secp256k1");
BigInteger pointN = spec.N;
try
{
BigInteger pointX = new BigInteger(1, sigR);
byte[] compEnc =
X9IntegerConverter.IntegerToBytes(pointX, 1 + X9IntegerConverter.GetByteLength(spec.Curve));
compEnc[0] = (byte)((sigV[0] & 1) == 1 ? 0x03 : 0x02);
ECPoint pointR = spec.Curve.DecodePoint(compEnc);
if (!pointR.Multiply(pointN).IsInfinity)
{
return(new byte[0]);
}
BigInteger pointE = new BigInteger(1, message);
BigInteger pointEInv = BigInteger.Zero.Subtract(pointE).Mod(pointN);
BigInteger pointRInv = new BigInteger(1, sigR).ModInverse(pointN);
BigInteger srInv = pointRInv.Multiply(new BigInteger(1, sigS)).Mod(pointN);
BigInteger pointEInvRInv = pointRInv.Multiply(pointEInv).Mod(pointN);
ECPoint pointQ = ECAlgorithms.SumOfTwoMultiplies(spec.G, pointEInvRInv, pointR, srInv);
byte[] pointQBytes = pointQ.GetEncoded(false);
return(pointQBytes);
}
catch (Exception e)
{
}
return(new byte[0]);
}
public X9ECPoint(ECPoint p, bool compressed)
{
this.p = p.Normalize();
this.encoding = new DerOctetString(p.GetEncoded(compressed));
}
/**
* Test encoding with and without point compression.
*
* @param p
* The point to be encoded and decoded.
*/
private void ImplTestEncoding(ECPoint p)
{
// Not Point Compression
byte[] unCompBarr = p.GetEncoded(false);
ECPoint decUnComp = p.Curve.DecodePoint(unCompBarr);
AssertPointsEqual("Error decoding uncompressed point", p, decUnComp);
// Point compression
byte[] compBarr = p.GetEncoded(true);
ECPoint decComp = p.Curve.DecodePoint(compBarr);
AssertPointsEqual("Error decoding compressed point", p, decComp);
}
static byte[] ExternalizeKey (ECPoint q)
{
// TODO Add support for compressed encoding and SPF extension
/*
* RFC 4492 5.7. ...an elliptic curve point in uncompressed or compressed format.
* Here, the format MUST conform to what the server has requested through a
* Supported Point Formats Extension if this extension was used, and MUST be
* uncompressed if this extension was not used.
*/
return q.GetEncoded ();
}
public K256VerifyingKey(ECPoint pub)
{
PubKey = pub;
PubKeyBytes = pub.GetEncoded(true);
SetVerifier(pub);
}
public static byte[] SerializeECPoint(byte[] ecPointFormats, ECPoint point)
{
ECCurve curve = point.Curve;
/*
* RFC 4492 5.7. ...an elliptic curve point in uncompressed or compressed format. Here, the
* format MUST conform to what the server has requested through a Supported Point Formats
* Extension if this extension was used, and MUST be uncompressed if this extension was not
* used.
*/
bool compressed = false;
if (ECAlgorithms.IsFpCurve(curve))
{
compressed = IsCompressionPreferred(ecPointFormats, ECPointFormat.ansiX962_compressed_prime);
}
else if (ECAlgorithms.IsF2mCurve(curve))
{
compressed = IsCompressionPreferred(ecPointFormats, ECPointFormat.ansiX962_compressed_char2);
}
return point.GetEncoded(compressed);
}
