public PublicKey(string hex)
{
byte[] data = StrUtils.HexToBytes(hex);
CompressedRistretto compressed = new CompressedRistretto(data);
this.Key = compressed.Decompress();
}
public KeyPair(RNGCryptoServiceProvider rng)
{
byte[] b = new byte[64];
rng.GetBytes(b);
this.PrivateKey = Scalar.FromBytesModOrderWide(b);
this.PublicKey = Constants.RISTRETTO_GENERATOR.Multiply(this.PrivateKey);
}
static Scalar HashMessage(RistrettoElement point, byte[] data)
{
try
{
using var sha = SHA512.Create();
sha.Initialize();
var combined = point.Compress().ToByteArray().Concat(data).ToArray();
byte[] hashed = sha.ComputeHash(combined);
return(Scalar.FromBytesModOrderWide(hashed));
}
catch (Exception e)
{
Console.WriteLine(e.StackTrace);
}
return(null);
}
/// <summary>
/// checks that a signature is valid for a set of public keys and messages
/// </summary>
/// <param name="publicKeys"></param>
/// <param name="messages"></param>
/// <returns></returns>
public Either <Error, Void> Verify(IList <RistrettoElement> publicKeys, IList <byte[]> messages)
{
if (!(publicKeys.Count() == messages.Count() && publicKeys.Count() == this.Parameters.Count()))
{
return(new Either <Error, Void>(new InvalidFormat()));
}
RistrettoElement zP = Constants.RISTRETTO_GENERATOR.Multiply(this.Z);
RistrettoElement eiXi = RistrettoElement.IDENTITY;
for (int i = 0; i < publicKeys.Count(); i++)
{
Scalar e = HashMessage(publicKeys[i], messages[i]);
eiXi = eiXi.Add(publicKeys[i].Multiply(e));
}
RistrettoElement diAi = RistrettoElement.IDENTITY;
foreach (RistrettoElement item in Parameters)
{
List <RistrettoElement> ristrettoElements = new List <RistrettoElement> {
item
};
Scalar d = HashPoints(ristrettoElements);
diAi = diAi.Add(item.Multiply(d));
}
RistrettoElement res = zP.Add(eiXi).Subtract(diAi);
if (res.Equals(RistrettoElement.IDENTITY))
{
return(new Right(null));
}
else
{
return(new InvalidSignature());
}
}
public PublicKey(byte[] data)
{
CompressedRistretto compressed = new CompressedRistretto(data);
this.Key = compressed.Decompress();
}
public PublicKey(RistrettoElement publicKey)
{
this.Key = publicKey;
}
public KeyPair(byte[] b)
{
this.PrivateKey = Scalar.FromBytesModOrderWide(b);
this.PublicKey = Constants.RISTRETTO_GENERATOR.Multiply(this.PrivateKey);
}
public KeyPair(string hex)
{
byte[] b = StrUtils.HexToBytes(hex);
this.PrivateKey = Scalar.FromBytesModOrder(b);
this.PublicKey = Constants.RISTRETTO_GENERATOR.Multiply(this.PrivateKey);
}