Decompose the standard algorithm name into sub-elements.
Disabled key algorithms are applied to all certificates, including the root CAs.
"RSA keySize < 2048, DSA keySize < 2048, EC keySize < 224"
Disabled signature algorithms are applied to signed certificates in a certificate chain, not including CA certs.
"MD2, MD4, MD5"
Returns the keySize of the given key, or None if no key exists.