/// <summary>
/// Check if the master key of the specified generation is correct.
/// </summary>
/// <param name="s">The <see cref="KeySet"/> to test.</param>
/// <param name="generation">The generation to test.</param>
/// <returns><see langword="true"/> if the key is correct.</returns>
private static bool TestKeyGeneration(KeySet s, int generation)
{
ReadOnlySpan <AesKey> keyVectors = MasterKeyVectors(s);
// Decrypt the vector chain until we get Master Key 0
AesKey key = s.MasterKeys[generation];
for (int i = generation; i > 0; i--)
{
Aes.DecryptEcb128(keyVectors[i], key, key);
}
// Decrypt the zeros with Master Key 0
Aes.DecryptEcb128(keyVectors[0], key, key);
// If we don't get zeros, MasterKeys[generation] is incorrect
return(key.IsZeros());
}
