public byte[] GeneratePassword(int passwordLength, PasswordRequirement fallbackChars, params PasswordRequirement[] reqs)
{
var indexProvider = _cryptoRandom;
var password = new byte[passwordLength];
var indexes = Enumerable.Range(0, passwordLength).ToList();
for (var i = 0; i < passwordLength; i++)
{
var indexPointer = indexProvider.Next(0, indexes.Count);
var index = indexes[indexPointer];
indexes.RemoveAt(indexPointer);
var actual = reqs.Sum(z => z.Required - z.Used);
var fallback = true;
foreach (var req in reqs)
{
var result = Rand(req.Used, req.Required, (passwordLength - i) - actual - req.Required - req.Used);
if (result)
{
var value = req.RandomValue();
password[index] = Encoding.UTF8.GetBytes(new[] { value }, 0, 1)[0];
req.Used++;
fallback = false;
break;
}
}
if (fallback)
password[index] = (byte)fallbackChars.RandomValue();
}
return password;
}
public byte[] GeneratePassword(PasswordSettings settings)
{
var fallback = new PasswordRequirement(0, AlphaChars);
var password = GeneratePassword(settings.Length, fallback,
new PasswordRequirement(settings.MinimumNonAlphaChars, settings.MaximumNonAlphaChars, settings.IsUsKeyboard ? UsKeyboardNonAlphas : NonAlphas),
new PasswordRequirement(settings.MinimumUpperCase, settings.MaximumUpperCase, UpperAlphaChars),
new PasswordRequirement(settings.MinimumDigits, settings.MaximumDigits, DigitChars)
);
return password;
}
