[Maria-discuss] Key lengths for file_key_management plugin

I've asked directly in the documentation page, but maybe someone will know answer here: https://mariadb.com/kb/en/mariadb/data-at-rest-encryption/#comment_2346 In that article it is said that 128, 192 or 256-bit keys are supported, but later AES_CTR and AES_CBC modes talk only about 128bit keys. What piece of information am I missing? Honza