public async Task WriteChecksAndEmbeddedDataAsync()
{
OutData.Position = 0;
await OutData.WriteAsync(BitConverter.GetBytes(MagicNumber), 0, 4);
await OutData.WriteAsync(BitConverter.GetBytes(DataVersionNumber), 0, 2);
await OutData.WriteAsync(BitConverter.GetBytes(MinCompatibleDataVersionNumber), 0, 2);
await OutData.WriteAsync(IV, 0, 16);
await OutData.WriteAsync(Salt, 0, 32);
var kcv = KeyCheckValueValidator.GenerateKeyCheckValue(Key);
OutData.Write(kcv, 0, 19);
long currentPosition = OutData.Position;
var mac = MessageAuthenticationCodeValidator.CalculateMessageAuthenticationCode(Key, OutData, HeaderSize);
Debug.Assert(currentPosition == OutData.Position, "Stream position is changed after generating MAC");
await OutData.WriteAsync(mac, 0, 48);
OutData.Position = 0;
}
public void AlteredKeyCheckValueIsNotValid()
{
byte[] key = CryptoRandom.NextBytesStatic(32);
byte[] kcv = KeyCheckValueValidator.GenerateKeyCheckValue(key);
if (key[0] > 120)
{
key[0]--;
}
else
{
key[0]++;
}
bool exceptionWasThrown = false;
try
{
KeyCheckValueValidator.ValidateKeyCheckValue(key, kcv);
}
catch (KeyCheckValueValidationException)
{
exceptionWasThrown = true;
}
Assert.True(exceptionWasThrown, "Validation of KCV should have failed, but it didn't");
}
public void UnalteredKeyCheckValueIsValid()
{
byte[] key = CryptoRandom.NextBytesStatic(32);
byte[] kcv = KeyCheckValueValidator.GenerateKeyCheckValue(key);
bool exceptionWasThrown = false;
try
{
KeyCheckValueValidator.ValidateKeyCheckValue(key, kcv);
}
catch (KeyCheckValueValidationException)
{
exceptionWasThrown = true;
}
Assert.False(exceptionWasThrown, "Validation of KCV has failed");
}
public void KeyCheckValidIs19BytesLong()
{
byte[] key = CryptoRandom.NextBytesStatic(32);
byte[] kcv = KeyCheckValueValidator.GenerateKeyCheckValue(key);
Assert.True(kcv.Length == 19, "KCV is not 19 bytes long");
}