public void TestExchange()
{
var a = new KeyExchanger();
var b = new KeyExchanger();
var aKey = a.KeyFromToken(b.Token);
var bKey = b.KeyFromToken(a.Token);
CollectionAssert.AreEqual(aKey, bKey);
}
/// <summary>
/// Protects an insecure connection.
/// </summary>
/// <param name="initiator">Set to <see langword="true"/> if a client,
/// <see langword="false"/> if a server.</param>
public static async Task <ProtectedMessenger> Protect(SocketMessenger socketMessenger, bool initiator)
{
// Perform a key exchange.
var exchanger = new KeyExchanger();
var sent = socketMessenger.Send(exchanger.Token);
var token = await socketMessenger.Receive().ConfigureAwait(false);
if (token.IsError)
{
throw new Exception(token.Error.GetType().ToString());
}
var key = exchanger.KeyFromToken(token.Value);
var result = await sent;
if (result.IsError)
{
throw new Exception(result.Error.GetType().ToString());
}
// Send test data.
var protectedMessenger = new ProtectedMessenger(socketMessenger, key, initiator);
byte[] myValues = SecureRandomGenerator.GetBytes(32);
var a = protectedMessenger.Send(myValues);
// Echo bytes back.
var integrityChallenge = await protectedMessenger.Receive().ConfigureAwait(false);
var b = protectedMessenger.Send(integrityChallenge);
await Task.WhenAll(a, b).ConfigureAwait(false);
// Check integrity of test data.
var integrityCheck = await protectedMessenger.Receive();
if (!Enumerable.SequenceEqual <byte>(myValues, integrityCheck))
{
throw new Exception("Could not verify connection!");
}
// Return protected messenger, as the connection has been validated.
return(protectedMessenger);
}
