public static void EnsureKmsProvidersAreValid(IReadOnlyDictionary<string, IReadOnlyDictionary<string, object>> kmsProviders)
{
    foreach (var kmsProvider in kmsProviders)
    {
        foreach (var option in Ensure.IsNotNull(kmsProvider.Value, nameof(kmsProvider)))
        {
            var optionValue = Ensure.IsNotNull(option.Value, "kmsProviderOption");
            var isValid = optionValue is byte[] || optionValue is string;
            if (!isValid)
            {
                throw new ArgumentException($"Invalid kms provider option type: {optionValue.GetType().Name}.");
            }
        }
    }
}