I'm a little confused here. The author compares S-Cache to 'sudo'. 'sudo' is a command that lets an unprivileged user run a privileged command. S-Cache lets a process access a secret without having to manage it. The process (in a sense) is not _privileged_ enough to see the secret but rather delegates this to S-Cache. The author (as far as I can tell) does not mention the shadow passwords file. Can you explain more?