public void Should_return_empty_array_if_size_is_zero()
{
var generator = new Salsa20RandomGenerator(_key);
var output = generator.GetRandomBytes(0);
Assert.Equal(0U, output.Length);
}
public void Should_generate_random_bytes()
{
var generator = new Salsa20RandomGenerator(_key);
var output = generator.GetRandomBytes(32);
Assert.Equal(
"PgWWBZItJSLD8I7lZSjIFXXId8R743waCzmYYrAKDUo=",
CryptographicBuffer.EncodeToBase64String(output));
}
public void Should_generate_different_bytes_after_each_request()
{
var generator = new Salsa20RandomGenerator(_key);
var first32 = generator.GetRandomBytes(32);
var second32 = generator.GetRandomBytes(32);
Assert.False(CryptographicBuffer
.Compare(first32, second32));
}
public void Should_generate_same_bytes_if_same_key()
{
var generator = new Salsa20RandomGenerator(_key);
var first32 = generator.GetRandomBytes(32);
var generator2 = new Salsa20RandomGenerator(_key);
var second32 = generator2.GetRandomBytes(32);
Assert.True(CryptographicBuffer
.Compare(first32, second32));
}
private static void Decrypt(FileHeaders headers, XDocument doc)
{
var protectedStrings = doc.Descendants("Entry")
.SelectMany(x => x.Elements("String"))
.Select(x => x.Element("Value"))
.Where(x =>
{
var protect = x.Attribute("Protected");
return(protect != null && (bool)protect);
});
IRandomGenerator generator;
switch (headers.RandomAlgorithm)
{
case CrsAlgorithm.ArcFourVariant:
generator = new Rc4RandomGenerator(
headers.ProtectedStreamKey);
break;
default:
generator = new Salsa20RandomGenerator(
headers.ProtectedStreamKey);
break;
}
foreach (var protectedString in protectedStrings)
{
var encrypted = Convert.FromBase64String(
protectedString.Value);
var length = encrypted.Length;
var padding = generator.GetRandomBytes(length);
for (var i = 0U; i < length; i++)
{
encrypted[i] ^= padding.GetByte(i);
}
protectedString.Value = Encoding.UTF8
.GetString(encrypted, 0, length);
}
}