/// <summary>
/// GetKeys provides an enumerator over all of the keys that are stored in the key storage
/// provider. This overload of GetKeys allows you to enumerate over only the user keys in the KSP
/// or only the machine keys. It also allows you to return only keys that are usable with a
/// specified algorithm.
/// </summary>
/// <param name="provider">CngProvider to enumerate the keys of</param>
/// <param name="openOptions">options to use when opening the CNG keys</param>
/// <param name="algorithm">algorithm that the returned keys should support</param>
/// <exception cref="ArgumentNullException">if <paramref name="algorithm" /> is null</exception>
public static IEnumerable <CngKey> GetKeys(this CngProvider provider,
CngKeyOpenOptions openOptions,
CngAlgorithm algorithm)
{
if (algorithm == null)
{
throw new ArgumentNullException("algorithm");
}
return(from key in provider.GetKeys(openOptions)
where key.Algorithm == algorithm
select key);
}
