public static (Hash, Signature) GetHashAndSignature(this Unpacker unpacker, int dataOffset, int dataSize)
{
var signatureKeyType = (KeyTypes)unpacker.UnpackByte();
unpacker.Position--;
var signatureSize = Signature.GetSignatureBytes(signatureKeyType);
unpacker.Unpack(out byte[] signatureData, signatureSize);
var position = unpacker.Position;
var signature = Signature.Restore(new ArraySegment <byte>(signatureData));
var partialStream = new PartialStream(unpacker.Stream, dataOffset, dataSize);
var signatureHash = Hash.Generate(signature.DataHashType, partialStream);
unpacker.Position = position;
return(signatureHash, signature);
}
public static (Hash, Signature) AddSignature(this Packer packer, Key signKey, int dataOffset, int dataSize)
{
if (!signKey.IsPrivate)
{
throw new ArgumentException("Key is not private", nameof(signKey));
}
var partialStream = new PartialStream(packer.Stream, dataOffset, dataSize);
var hash = Hash.Generate(Protocol.MessageHashType, partialStream);
var signature = Signature.Generate(signKey, hash);
var signature2 = Signature.Generate(signKey, hash);
if (signature != signature2)
{
throw new Exception("Invalid signature computation");
}
Pack(packer, signature);
return(hash, signature);
}