Manual:WrapOldPasswords.php

Details
wrapOldPasswords.php file is a maint-scripts>Special:MyLanguage/Manual:Maintenance scripts|maintenance script to wrap all passwords of a certain type in a specified layered type that wraps around the old type.

If necessary, the old MD5 hashing can be restored by changing   to 'B'.

wrapOldPasswords.php can wrap all passwords in pbkdf2-legacyA or pbkdf2-legacyB (or the hashing algorithm of your choice) if you don't want to wait for your users to log in.