public static void Main(string[] args)
{
TimeSpan validityDuration;
int passwordDigits;
string secret;
if (args.Length < 3)
{
Console.WriteLine("usage: shared_secret password_validity_duration_seconds password_length");
return;
}
else
{
secret = args[0];
// Note: not validated.
validityDuration = TimeSpan.FromSeconds(int.Parse(args[1]));
passwordDigits = int.Parse(args[2]);
}
var key = Encoding.UTF8.GetBytes(secret);
bool isExiting = false;
Console.CancelKeyPress += (s, e) => isExiting = true;
Console.Clear();
while (!isExiting)
{
Console.Write("Password to test: ");
var codeToTest = Console.ReadLine().Trim();
var code = Topt.GetCode(key, DateTime.UtcNow, validityDuration, passwordDigits);
Console.WriteLine((code == codeToTest) ? "✅ Valid " : "⛔ ️ Incorrect Password");
Console.WriteLine(code);
}
}
public void MoreThanThirtySecondDifferent()
{
var time = DateTime.Today;
var code1 = Topt.GetCode(sharedKey, time, validity, digits);
var code2 = Topt.GetCode(sharedKey, time + validity, validity, digits);
Assert.That(code1, Is.Not.EqualTo(code2));
}
public void WithinThirtySecondSameCode()
{
var time = DateTime.Today;
var code1 = Topt.GetCode(sharedKey, time, validity, digits);
var code2 = Topt.GetCode(sharedKey, time + validity - TimeSpan.FromMilliseconds(1), validity, digits);
Assert.That(code1, Is.EqualTo(code2));
}
public void SameTimeGeneratesSameCode()
{
var now = DateTime.UtcNow;
var code1 = Topt.GetCode(sharedKey, now, validity, digits);
var code2 = Topt.GetCode(sharedKey, now, validity, digits);
Assert.That(code1, Is.EqualTo(code2));
}
public void ShorterValidityDifferent()
{
var shorterValidity = TimeSpan.FromSeconds(5);
var time = DateTime.Today;
var code1 = Topt.GetCode(sharedKey, time, validity, digits);
var code2 = Topt.GetCode(sharedKey, time + shorterValidity, shorterValidity, digits);
Assert.That(code1, Is.Not.EqualTo(code2));
}
public void DigitsControlsLength()
{
var time = DateTime.Today;
var code1 = Topt.GetCode(sharedKey, time, validity, digits);
var code2 = Topt.GetCode(sharedKey, time, validity, digits + 1);
var code3 = Topt.GetCode(sharedKey, time, validity, digits + 2);
Assert.That(code1.Length, Is.EqualTo(digits));
Assert.That(code2.Length, Is.EqualTo(digits + 1));
Assert.That(code3.Length, Is.EqualTo(digits + 2));
}
public void SameTimeDifferentKey()
{
var time = DateTime.Today;
var code1 = Topt.GetCode(sharedKey, time, validity, digits);
var key = new byte[64];
rng.GetBytes(key);
var code2 = Topt.GetCode(key, time, validity, digits);
Assert.That(code1, Is.Not.EqualTo(code2));
}