markus reichelt | 6 Oct 22:06 2010

September 2010 Review

Well, I'm going to give it some more months. Let's see where this
goes. (Needless to say, feel free to chime in, anything linux crypto
related is welcome. Just go for it.)

 - loop-AES-v3.4b file/swap crypto package was released on 2010-09-23:
   http://www.spinics.net/lists/crypto/msg04992.html

   quoting its release log:
    - Worked around block layer interface breakage on linux-2.6.36-rc
      kernels.
    - Added workaround for device open/close reference count race.
      This race caused random loop-AES "make tests" failures with
      "ioctl: LOOP_CLR_FD: Device or resource busy" error message.
      The workaround is in util-linux patch (new mount/umount/losetup/
      swapon binaries). Thanks to Julien Moutinho for reporting/testing
      this problem. 

 - Version 0.4.2 of loop-AES FAQ was released on 2010-10-06:
   #43 added, #17 adapted, #33 adapted to loop-AES-v3.4b, new patches added
   - FAQ 43: make tests fails: Device busy
     - solution given via release of loop-AES-v3.4b
   - FAQ 33: Why does loop-AES still ask for a password instead of a
     passphrase?
     - new patches for loop-AES-v3.4b
   - FAQ 17: Which distros include loop-AES?
     - Gentoo [version unclear - contributed info, thanks]

Better late than never - Vidalia - August 2010 catch-up:

 - Vidalia 0.2.10 released on Aug 26 2010
(Continue reading)

netguru | 7 Oct 21:34 2010
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SSE2 optimizations for Serpent in XTS mode.

Hello everyone,

Recently i was looking at libbotan's changelog, and i found that using
SSE2 parallell processing for serpent was quite a speed improvement.

Same  in  the neat little DiskCryptor program, wich uses the same kind
of optimization for serpent in XTS mode.

There  is  no  point in using SSE2 in CBC and other modes wich require
sequential  processing, but in XTS's (and a few other modes) case this
really makes a big difference.

Is  there anyone capable and or willing to implement this in the linux
kernel  ?  Maybe  in  the  form of a patch or a module ? Dont have the
sources  from  the  diskcryptor implementation, but libbotan does sure
have one as well.

Regards...

-
Linux-crypto:  cryptography in and on the Linux system
Archive:       http://mail.nl.linux.org/linux-crypto/

Lars Reimann | 20 Oct 16:14 2010
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Re: Huge Problem with cryptoloop and AES: Lost Password

Hi,

I just wanted to shortly ask, if there have any tools emerged since my
initial post, which could help me on the recovery on my lost password
for losetup:

losetup -e AES256 -C 500 /dev/loop0 /dev/md2

The proposed way was to use brute force and try to compute passwords and
check if they result in (03 ... 00) (ext2 zero sectors).

Any hints / refs to snippets would be helpful!

I am currently on AMD64.

greetings,
l.r.

On 18.11.2006 13:52, Jari Ruusu wrote:
> Lars Reimann wrote:
>> I stored my 20 character passwords on my palm device only (i know by now
>> that this was stupid!). However, that one chrashed and apparently all data
>> was lost, including passwords. However, i may remember certain details of
>> the password, for example which characters I used not, and how the
>> password ends.
> This won't help you now, but one way to handle lost/forgotten passphrases is
> to use gpg encrypted key files where all key files are encrypted using both
> employer's "recovery" public key and user's public key. Employer's
> "recovery" public key can be distributed to everyone, and copies of private
> keys physically locked in a safe. That way employer can recover user's data
(Continue reading)

Jari Ruusu | 21 Oct 15:53 2010
Picon
Picon

Re: Huge Problem with cryptoloop and AES: Lost Password

Lars Reimann wrote:
> I just wanted to shortly ask, if there have any tools emerged since my
> initial post, which could help me on the recovery on my lost password
> for losetup:
> 
> losetup -e AES256 -C 500 /dev/loop0 /dev/md2
> 
> The proposed way was to use brute force and try to compute passwords and
> check if they result in (03 ... 00) (ext2 zero sectors).
> 
> Any hints / refs to snippets would be helpful!

In private email, another person asked almost same question. Below is what I
wrote to him/her. It is a script that reads possible passwords from a file,
one password per line. Quote:

I would do this scripting using aespipe, which is available from
http://loop-aes.sourceforge.net/ . For many file systems, such as ext2,
ext3, reiserfs, and possibly others, the file system's fourth 512 byte
plaintext sector is all zero bytes. This known plaintext can be used to
determine if the passphrase is correct. Additional bonus is that you don't
have to mess with original file system when trying to brute force the
passphrase.

# echo "1234567890 1234567890 5" | losetup -p 0 -v -C 3 -e AES256 /dev/loop0 /dev/fd0
# mkfs -t ext2 -q /dev/loop0
# losetup -d /dev/loop0
# chmod u+x brute.sh
# cat brute.sh 
#/bin/bash
(Continue reading)

markus reichelt | 24 Oct 08:17 2010

Re: Huge Problem with cryptoloop and AES: Lost Password

* Lars Reimann <mail <at> lars-reimann.de> wrote:

> Any hints / refs to snippets would be helpful!

...

This is so annoying, the mailinglist ate a post once again.
At least the archive has it:
http://mail.nl.linux.org/linux-crypto/2010-10/msg00003.html

Also, there's the usenet group gmane.linux.cryptography, check
http://dir.gmane.org/gmane.linux.cryptography

--

-- 
left blank, right bald
loop-AES FAQ: http://mareichelt.de/pub/texts.loop-aes.php#faq

Gmane