private void CalculateProofs()
{
var hash = Hash.Sha1();
var password = _saslprep.Run(Password);
var saltedPassword = hash.ComputeHash(
_encoding.GetBytes(password),
_serverFirstMessage.Salt.Value,
_serverFirstMessage.Iterations.Value);
var clientKey = hash.ComputeHash(_encoding.GetBytes("Client Key"), saltedPassword);
var serverKey = hash.ComputeHash(_encoding.GetBytes("Server Key"), saltedPassword);
var storedKey = hash.ComputeHash(clientKey);
var authMessage =
$"{_clientFirstMessage.BareMessage},{_serverResponse},{_clientFinalMessage.MessageWithoutProof}";
Logger.Log(LogLevel.Debug, $"Auth message: {authMessage}");
var auth = _encoding.GetBytes(authMessage);
var signature = hash.ComputeHash(auth, storedKey);
_serverSignature = new List <byte>(hash.ComputeHash(auth, serverKey));
var proof = clientKey.ExclusiveOr(signature);
_clientFinalMessage.SetProof(proof);
}
public void Authenticate()
{
var clientFirstMessage = new ClientFirstMessage(_username, _nonce);
Send(clientFirstMessage.Message);
var serverFirstMessage = ServerFirstMessage.ParseResponse(Receive());
var hashedPassword = Hash.ComputeHash(Encoding.UTF8.GetBytes(_password), serverFirstMessage.Salt.Value,
serverFirstMessage.Iterations.Value);
var clientKey = Hash.ComputeHash(Encoding.UTF8.GetBytes("Client Key"), hashedPassword);
var serverKey = Hash.ComputeHash(Encoding.UTF8.GetBytes("Server Key"), hashedPassword);
var storedKey = Hash.ComputeHash(clientKey);
var clientFinalMessage = new ClientFinalMessage(clientFirstMessage, serverFirstMessage);
var authMessage =
$"{clientFirstMessage.BareMessage},{serverFirstMessage},{clientFinalMessage.MessageWithoutProof}";
var clientSignature = Hash.ComputeHash(Encoding.UTF8.GetBytes(authMessage), storedKey);
var serverSignature = Hash.ComputeHash(Encoding.UTF8.GetBytes(authMessage), serverKey);
var clientProof = clientKey.ExclusiveOr(clientSignature);
clientFinalMessage.SetProof(clientProof);
Send(clientFinalMessage.Message);
var serverFinalMessage = ServerFinalMessage.ParseResponse(Receive());
if (!serverFinalMessage.ServerSignature.Equals(serverSignature))
{
throw new InvalidOperationException();
}
}
public void When_ProofIsSetAsString_PropertiesShouldBeValid()
{
var clientFirst = new ClientFirstMessage("user", "nonce");
var serverFirst = new ServerFirstMessage(4096, "nonce", "salt");
var message = new ClientFinalMessage(clientFirst, serverFirst);
message.SetProof("bf45fcbf7073d93d022466c94321745fe1c8e13b");
message.Channel.Value.ShouldBe("biws");
message.Nonce.Value.ShouldBe("nonce");
message.Proof?.ToString().ShouldBe("p=bf45fcbf7073d93d022466c94321745fe1c8e13b");
message.Message.ShouldBe("c=biws,r=nonce,p=bf45fcbf7073d93d022466c94321745fe1c8e13b");
message.MessageWithoutProof.ShouldBe("c=biws,r=nonce");
}
