CentOS docs - Sep 2006 - Encrypted partition short howto

I've written a short howto on creating and mounting an encrypted 
filesystem using dm-crypt. The doc currently lives on our internal 
wiki (Trac) at work, but I'd love to rewrite and post for a general 
readership. I suppose the proposed URL would be something like

  http://wiki.centos.org/TipsAndTricks/EncryptedFilesystem

-- 
Paul Heinlein <> heinlein at madboa.com <> www.madboa.com

Paul Heinlein wrote:
> I've written a short howto on creating and mounting an encrypted 
> filesystem using dm-crypt. The doc currently lives on our internal 
> wiki (Trac) at work, but I'd love to rewrite and post for a general 
> readership. I suppose the proposed URL would be something like
> 
>   http://wiki.centos.org/TipsAndTricks/EncryptedFilesystem
Assuming that your username on the wiki is PaulHeinlein, that page is
now all yours to fool around with.

Thanks,

Ralph
-- 
Ralph Angenendt......ra at br-online.de | .."Text processing has made it
possible
Bayerischer Rundfunk...80300 M?nchen | ....to right-justify any idea, even one
Programmbereich.Bayern 3, Jugend und | .which cannot be justified on any other
Multimedia.........Tl:089.5900.16023 | ..........grounds." -- J. Finnegan,
USC
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
URL:
<http://lists.centos.org/pipermail/centos-docs/attachments/20060907/016284f9/attachment.sig>

Paul Heinlein wrote:
> I've written a short howto on creating and mounting an encrypted 
> filesystem using dm-crypt. The doc currently lives on our internal 
> wiki (Trac) at work, but I'd love to rewrite and post for a general 
> readership. I suppose the proposed URL would be something like
> 
>   http://wiki.centos.org/TipsAndTricks/EncryptedFilesystem
> 
go ahead, send us a draft here :)

btw, i've used your svn + trac guide ! { it could use some fluffing up
though... }

-- 
Karanbir Singh : http://www.karan.org/ : 2522219 at icq

(Sorry for top-posting, I have just added myself to the list.)

Hi Paul,
> I've written a short howto on creating and mounting an encrypted 
> filesystem using dm-crypt.
Thanks for the HOWTO. Some (fairly trivial) suggestions for improvement:

- Although cryptsetup is in base, it would be nice to mention what
  packages are involved.
- Using a partition as physical storage is such a common use case,
  that it seems useful to me to describe this explicitly.
- The HOWTO describes writing zeros to the file that will hold the 
  encrypted file system, and how to use this file afterwards
  without any further measures to obscure the virtual device.
  This is bad, because an attacker can easily determine what parts
  of the raw file contain data blocks, and what parts contain no data.
  It is much better to set up the encrypted device first, and write
  zeros to the encryped device (i.e. /dev/mapper/secretfs). This will
  look like random data in the raw file or partition, making it
  virtually impossible to grab data blocks for further analysis.
- The following line is fairly useless without any further
  parameters: "tune2fs /dev/mapper/secretfs"
- A wishlist item: encrypted CDs. Very handy for having secured
  backup copies.

-- Daniel