krb5_keytab_entry

A keytab entry consists of

• a principal -- the identity of an actor we want to authenticate
• a keyblock -- encryption keys derived from the principal's password
• a key version number (kvno) -- a sequence number indicating which of the principal's historical passwords the keyblock was derived from.

You can think of a keytab as the set of identities one may take on as the holder of a particular password.

principal and keyblock return copies of underlying kerberos structures.