Re: [dm-devel] [PATCH] dm-crypt: disable block encryption with arc4

[Milan Broz <mbroz redhat com>]

On 01/25/2010 07:29 PM, Mikulas Patocka wrote:
> Hi
> 
> When using arc4 to encrypt a block device, the resulting device is 
> unreliable. It reads garbage. That's because arc4 is a stream cipher, if 
> you write something, it advances its state and if you attempt to decrypt 
> the same sector, it uses new state that is different.
> 
> This patch disables the use of arc4 on block devices.

arc4 again. it is simply not a block cipher:-)

This should be solved inside cryptoAPI and not blacklist it in dm-crypt,
see that thread
http://article.gmane.org/gmane.linux.kernel.cryptoapi/3441

Milan