Re: loopback DES encryption not working (2.2pre4, util-linux-2.9f)

Alexander Kjeldaas (astor@guardian.no)
Thu, 7 Jan 1999 20:16:25 +0100


On Thu, Jan 07, 1999 at 12:14:50AM +0100, Tobias Richter wrote:
> with linux 2.2.0pre4 and the losetup that comes with util-linux-2.9f
> I get:
>
> [root@cave /]# /sbin/losetup -e DES /dev/loop0 /file
> Password:
> Init (up to 16 hex digits):
> ioctl: LOOP_SET_STATUS: Invalid argument
>
> XOR 'encryption' works. What's wrong here?
>
> By the way is there a version of losetup that supports those other
> encryption methods like Twofish, Blowfish, IDEA and such?
>

There isn't any crypto code in the vanilla kernel yet. You have to
apply the international kernel patch available at:

ftp://ftp.kerneli.org/pub/linux/kerneli/v2.1/ [the patch-int-* files]

Select 'General encryption support' under block devices and the
ciphers you want to use under the 'Crypto options' menu. This
"general" loop device module supports blowfish, des, dfc, idea, mars,
rc6, and serpent encryption (using the crypto library). In addition,
there are two additional loop device modules that support twofish and
cast-128 (untested).

To use these other ciphers, losetup must be patched. There is a patch
in linux/Documentation/crypto for util-linux-2.9e that you can use for
this purpose.

For other ciphers than DES, losetup expects a password phrase which is
hashed using RIPEMD-160 instead of a hex string.

astor

-- 
 Alexander Kjeldaas, Guardian Networks AS, Trondheim, Norway
 http://www.guardian.no/

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/