Hi All
Can anyone give me any pointers to an encrypted file system for QNX4, e.g. a
special version of (or addition to) Fsys? In short, I want to make a
tamper-proof boot floppy that requires a key to be able to mount and use the
file system. Any ideas would be highly appreciated.
Roelof van Wyk
Previously, news.eu.concert.net wrote in comp.os.qnx:
Can anyone give me any pointers to an encrypted file system for QNX4, e.g. a
special version of (or addition to) Fsys? In short, I want to make a
tamper-proof boot floppy that requires a key to be able to mount and use the
file system. Any ideas would be highly appreciated.
There is more than one way to do this, but here is one that I’ve played
with.
Run BlkFsys with an attached name different from Fsys.
Start the Fsys.floppy driver pointing to BlkFsys. This
will allow you to access sectors on the floppy drive, but
not a file system.
Now, write a QNX disk driver as follows. Instead of writing
code to access hardware, instead open the /dev/fd0 device that
Blkfsys has created for you. Fsys will then create a new block I/O
device which you could call /dev/efd0.
Now, within your driver you can put encrypt/decrypt code.
It can be based on a key, and can also use information such
as the specific block being encrypted. Note that a simple
XOR’ing of a pattern is not very strong as any ZERO sectors
will make this apparent.
Mitchell Schoenbrun --------- maschoen@pobox.com