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I've got an encrypted drive, which I mount under Ubuntu (12.04) like:

# modprobe cryptoloop
# losetup -e AES128 /dev/loop0 /dev/sda5
# mount /dev/loop0 /mnt

But with a recent Debian install (6.0.6 Squeeze), this fails with:

# modprobe cryptoloop
FATAL: Module cryptoloop not found.
# losetup -e AES128 /dev/loop0 /dev/sda5
ioctl: LOOP_SET_STATUS: Invalid argument, requested cipher or key length (128 bits) not supported by kernel

Any ideas what I'm supposed to do instead?


This webpage

Implies that I should be able to do it using cryptsetup instead:

# cryptsetup create -c aes hola /dev/sda5
Enter passphrase: 

and that bit seems to work, but the drive won't then mount:

# mount /dev/mapper/hola /mnt
mount: you must specify the filesystem type

# mount -t ext4 /dev/mapper/hola /mnt
mount: wrong fs type, bad option, bad superblock on /dev/dm-0,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so
share|improve this question

FATAL: Module cryptoloop not found. is the problem.

You need to recompile the kernel with cryptoloop module support enabled. See this HOWTO for instructions on how to do this.

share|improve this answer
Thanks! I'm told that I should be able to do it with cryptsetup instead, but if that doesn't work I'll try the recompile. That's not something I've ever done before. Do those instructions work well on debian? – John Lawrence Aspden Dec 16 '12 at 19:52
No problem. Yes it will work fine, the kernel compile is generic and not distro-dependent, but you should ensure you load the current config beforehand so you keep the current settings/modules etc. If it's your first re-compile, I would install the new kernel image separately (in grub) so you can revert back in case anything unexpected happens. – Munkeh Dec 16 '12 at 19:57
Sweet, thanks. I feel brave... – John Lawrence Aspden Dec 16 '12 at 19:58
No need to feel scared, re-compiling the kernel is fairly straight forward as long as you carefully follow up to date instructions that are relevant to what you're trying to do. Just be sure you don't rush into anything. – John Hunt Aug 11 '14 at 9:00

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