Phil H wrote:
Thanks Matthias for your help (and Jari for the
clarification). However I'm still having problems.
I make a device-backed aes256-encrypted loop, where
the device is a floppy, format the loop device with
vfat, then deallocate the loop. Then I put the
following in /etc/fstab:
/dev/fd0 /home/dsl/crypt1 vfat
defaults,rw,noatime,encryption=aes256,noauto,user 0 0
(I've also tried using 'users' plus the guid etc
settings as for the fstab entries for my hard drives).
I'd always set uid/gid, to be sure.
(Personally i always use an automounter(autofs), here you have to provide the UID/GID as the mount-command is always issued from the automount-daemon in root-context.
Unfortunatly you can't use an automounter if you have to provide a password(*))
BUT when I try to mount as an ordinary user I get:
"mount: only root can do that"
I'd guess your mount-command misses the SUID-Bit.
ls -la /bin/mount
-rwsr-xr-x 1 root root 84888 Mar 23 12:58 /bin/mount
The fourth Character from the beginning must be an "s", without SUID-Bit there would be an "x".
Also mount must belong to root.
chown root.root /bin/mount
chmod 4755 /bin/mount
sudo mount works, but the mount directory has
root-only access permissions.
At this point you hadn't provided uid( & gid).
With sudo mount is called under the root account, so the "inherited" uid & gid are the ones from root.
This is why I has the wrong notions in my initial post
- I'd tried this before.
What is going wrong?
I'd say:
A mixture of subtle differences in your distro paired with a little bit of missing experience. :-)
PS: I'm using a knoppix-based distro
May only be relevant for the "doesn't ship with SUID-bit-set-for-mount"-part. AFAIR there are Distros with a bit more restrictive security regarding SUID programs. Maybe this is one if them.
*:
There are ways to cicumvent this, but that is no point here. :-)
--
Real Programmers consider "what you see is what you get" to be just as
bad a concept in Text Editors as it is in women. No, the Real Programmer
wants a "you asked for it, you got it" text editor -- complicated,
cryptic, powerful, unforgiving, dangerous.
-
Linux-crypto: cryptography in and on the Linux system
Archive: http://mail.nl.linux.org/linux-crypto/
