/// <summary>
/// Computes the client response containing the client's public key and
/// evidence.
/// </summary>
/// <param name="challenge">The challenge containing the protocol elements
/// received from the server in response to the initial client
/// response.</param>
/// <returns>An array of bytes containing the client's challenge
/// response.</returns>
/// <exception cref="SaslException">Thrown if the server specified any
/// mandatory options which are not supported.</exception>
private byte[] ComputeFinalResponse(byte[] challenge)
{
ServerMessage1 m = ServerMessage1.Deserialize(challenge);
// We don't support integrity protection or confidentiality.
if (!String.IsNullOrEmpty(m.Options["mandatory"]))
{
throw new SaslException("Mandatory options are not supported.");
}
// Set up the message digest algorithm.
var mda = SelectHashAlgorithm(m.Options["mda"]);
HashAlgorithm = Activator.CreateInstance(mda.Item2) as HashAlgorithm;
// Compute public and private key.
PublicKey = Helper.ComputeClientPublicKey(m.Generator,
m.SafePrimeModulus, PrivateKey);
// Compute the shared key and client evidence.
SharedKey = Helper.ComputeSharedKey(m.Salt, Username, Password,
PublicKey, m.PublicKey, PrivateKey, m.Generator, m.SafePrimeModulus,
HashAlgorithm);
ClientProof = Helper.ComputeClientProof(m.SafePrimeModulus,
m.Generator, Username, m.Salt, PublicKey, m.PublicKey, SharedKey,
AuthId, m.RawOptions, HashAlgorithm);
ClientMessage2 response = new ClientMessage2(PublicKey, ClientProof);
// Let the server know which hash algorithm we are using.
response.Options["mda"] = mda.Item1;
// Remember the raw options string because we'll need it again
// when verifying the server signature.
Options = response.BuildOptionsString();
return(response.Serialize());
}
public void SerializeClientSecondMessage()
{
BigInteger key = BigInteger.Parse(clientPublicKey,
NumberStyles.HexNumber);
Mpi _publicKey = new Mpi(key);
ClientMessage2 m = new ClientMessage2(_publicKey, clientProof);
m.InitialVector = clientInitialVector;
foreach (KeyValuePair <string, string> p in clientOptions)
{
m.Options.Add(p.Key, p.Value);
}
byte[] serialized = m.Serialize();
Assert.IsTrue(serialized.SequenceEqual(expectedClientMessage2));
}
