public override string Undo(string command)
{
if (command.TryConvertTo(out DefineRsaWorkingKeyRequest dwkRequest))
{
this.requestedRSAParameters = new RSAParameters()
{
Modulus = dwkRequest.Modulus.Value,
Exponent = dwkRequest.Exponent.Value
};
var rsaProvider = new RSACryptoServiceProvider(RSA_KEY_LENGTH);
this.detouredRSAParameters = rsaProvider.ExportParameters(true);
dwkRequest.Modulus.Value = this.detouredRSAParameters.Modulus;
dwkRequest.Exponent.Value = this.detouredRSAParameters.Exponent;
return(dwkRequest.ToString());
}
else if (command.TryConvertTo(out DefineRsaWorkingKeyResponse dwkResponse))
{
var privateRsaParameters = new RsaPrivateCrtKeyParameters(
new BigInteger(1, this.detouredRSAParameters.Modulus), new BigInteger(1, this.detouredRSAParameters.Exponent),
new BigInteger(1, this.detouredRSAParameters.D), new BigInteger(1, this.detouredRSAParameters.P),
new BigInteger(1, this.detouredRSAParameters.Q), new BigInteger(1, this.detouredRSAParameters.DP),
new BigInteger(1, this.detouredRSAParameters.DQ), new BigInteger(1, this.detouredRSAParameters.InverseQ)
);
var rsaEngine = new RsaEngine();
rsaEngine.Init(false, privateRsaParameters);
var processedBlock = rsaEngine.ProcessBlock(dwkResponse.Cryptogram.Value, 0, dwkResponse.Cryptogram.Value.Length);
var decryptedRsaCryptogram = new DecryptedRsaCryptogram();
decryptedRsaCryptogram.Init(new StringReader(Encoding.ASCII.GetString(processedBlock)));
this.WorkingKey = decryptedRsaCryptogram.WorkingKey.Value;
var publicRsaParameters = new RsaKeyParameters(false,
new BigInteger(1, this.requestedRSAParameters.Modulus), new BigInteger(1, this.requestedRSAParameters.Exponent)
);
rsaEngine.Init(true, publicRsaParameters);
var unprocessedBlock = Encoding.ASCII.GetBytes(decryptedRsaCryptogram.ToString());
dwkResponse.Cryptogram.Value = rsaEngine.ProcessBlock(unprocessedBlock, 0, unprocessedBlock.Length);
return(dwkResponse.ToString());
}
return(base.Undo(command));
}
public override BaseResponse Handle(string command)
{
if (command.TryConvertTo(out DefineRsaWorkingKeyRequest dwkRequest) == false)
{
return(null);
}
var decryptedRsaCryptogram = new DecryptedRsaCryptogram();
decryptedRsaCryptogram.SequentialNumber.Value = random.Next(0, 999999999);
this.WorkingKey = random.ByteArray(16);
decryptedRsaCryptogram.WorkingKey.Value = this.WorkingKey;
var rsaEngine = new RsaEngine();
rsaEngine.Init(true,
new RsaKeyParameters(false, new BigInteger(1, dwkRequest.Modulus.Value), new BigInteger(1, dwkRequest.Exponent.Value))
);
var unprocessedBlock = Encoding.ASCII.GetBytes(decryptedRsaCryptogram.ToString());
return(new DefineRsaWorkingKeyResponse(rsaEngine.ProcessBlock(unprocessedBlock, 0, unprocessedBlock.Length)));
}