amctrl.prx's PGD (BB) MAC and cipher functions, for kernel modules that
import them: the firmware's POPS manager checks and decrypts a store PS1
game's disc image with them. libkirk's amctrl.c reimplements the module, and
its MAC_KEY and CIPHER_KEY have the layout of the contexts the callers keep in
their own memory, so those are used in place. 6.60 NIDs.