Loopback FS?

[robophilosopher]

This is for the UNIXy of you out there...

I'm wondering if there's a way to mount a loopback filesystem under OS X... Specifically, I created a Knoppix encrypted home directory, which is AES-128 encrypted. To mount it under linux on an intel box, I would do something like this:
losetup -e aes -k 128 /dev/loop0 /dev/sda2
<type password>
mount /dev/loop0 /mnt/mystuff

losetup isn't a command under OS X, and my good buddy Google doesn't seem too promising. Do you guys have the inside scoop?

[cyberman]

If you just want to encrypt your home directory, there's FileVault. Open up the Accounts pane in System Preferences, and click security. (Basically, it replaces you home dir with an encrypted disk image and mounts the image where your home dir should be when you login)
I wouldn't recommend it, though, last time I read about it, there were still bugs, some of them causing data loss (things could have changed, however).


You can also make encrypted disk image using disk utility.


I'm pretty sure there isn't a loopback fs driver in OS X ):.

FreeBSD has a user space cryptographic file system implemented as a nfs server (according to them). You might be able to port it.
freebsd ports description:
http://www.freebsd.org/cgi/url.cgi?ports/security/cfs/pkg-descr
download of the freebsd port:
http://cvsweb.freebsd.org/ports/security/cfs/cfs.tar.gz?tarball=1

original author's page:
http://www.crypto.com/software/

[darkcaste]

Hey robophilosopher,

There's a BSD command called hdiutil which can be used to mount disk images:
hdiutil attach -readonly cdimage.iso

Btw, I know you asked months back, but I just spent hours on google trying to mount a cd image, by looking for lofs and losetup... hopefully this saves someone else some time. :)