Kernel Level File Integrity Checker report #8

[Efstratios Karatzas]

During week #8:

* clean up the codebase

* midterm eval

* checksums are now produced in kernel land during VOP_READ() and checked
against the ones from .pefs.checksum. If they don't match, we deny reading
access to that vnode.

Next tasks on the TODO list:

* research/implement signing .pefs.checksum and verifying that signature
during `/sbin/pefs verify` as well as during VFS_MOUNT().

* require that immutable flags are set for all files that require integrity
checking. this should be checked both by /sbin/pefs and in kernel when a
vnode is looked up in index tables to see if it requires integrity
checking. Also, add an option to `/sbin/pefs addchecksum` to set immutable
flags for all files in input list, in case they are not already set.

-- 

Efstratios "GPF" Karatzas