I had the loop device created using the gentoo 2.6 kernel and whatever loop and crypto modules are in the default gentoo 2.6 kernel. I didn't do any aditional compilation for loop-AES as far as I can remember (it was a while ago that I set it up). I created the loop device with a script that basically executed the command:
losetup -e aes-cbc-128 -p0 /dev/loop0 /dev/sdb1 < /etc/backup/aes.key
Where the aes.key file has a random alpanumeric string of 60 characters. It then mounts the /dev/loop0 device to the mount point with:
mount -t ext2 /dev/loop0 /mnt/backup
I backed up the script and key before reinstalling the system and put them back on the new system, but when I run the script it creates the /dev/loop0 with the same options sucessfully but fails to mount as it recons the ext2 fs isn't there or is corrupt. It is behaving as if the key is wrong but it is not.
The /dev/sdb1 device is a USB external disk. I have several of these devices with encrypted info on them, fortunatly, none of which is critical. One of the drives does have some stuff which I would like to recover to save having to set up again. As an experement I tried running mke2fs /dev/loop0 on one of the non important drives and it reinitialises the ext2 partition, which then sets up and mounts fine.
My main query is what would be difference between the way the gentoo 2.6 kernel and the SuSe 2.6 kernel handle the Crypto loop devices. I tried both the Cryptoloop that is in the standard SuSe kernel and I also compiled a custom Kernel without the loop device and compiled the loop-aes loop device that I downloaded from sourceforge. Both gave the same results of a sucessful execution of the losetup command but with an unreadable ext2 FS. I have checked the key is correct and it is, but the results are as if it was wrong. The only thing I can think of is that there is some difference between the two systems in the way the keys are handled, or there is some sort of seeding that I am unaware of.
Any help or suggestions would be greatfully acepted.
- Linux-crypto: cryptography in and on the Linux system Archive: http://mail.nl.linux.org/linux-crypto/
