plaintext into into an encrypted image and back into plaintext by
doing rump I/O on /dev/cgd. There is one test to check that giving
the same password for both encryption and decryption produces the
same plaintext and another to check that giving a different passwords
does not produce the same plaintext.
This could be fairly easily extended to test all feature of cgd
(hint hint). For example, now cgd.conf is included in cvs, but
the only reason for that is that without further hacking cgdconfig
uses /dev/random quality random to generate the salt for a
pkcsetcetc_kdf2 cgconfig -g, and making an automated test block on
the entropy pool is just not good form. Details are everything.