DRM Shoots Itself in the Foot, episode... oh, many

[David Koontz]

There are pdf viewers and pdf image and text extraction tools for
various platforms that allow you to extract content despite the
document Security Methods specification of Document Restrictions. 
Failing that you could always do screen grabs and Optical Character
Recognition.

DRM failing because they let people actually see their super-Sekrets.

Saw a fun one recently, watermarks whose text becomes opaque after
printing once.  Gee, you make the file ugo-w, or should you start
looking out for signs of a root kit?

D.



--- Peter Gutmann <pgut001 at cs.auckland.ac.nz> wrote:

> Lets say you've been tasked with implementing a DRM system.  So you
> go to the
> Digital Content Protection LLC site and download the HDCP spec, which
> contains
> all the test vectors, sample keys, and whatnot, that you need for
> HDCP.
> 
> However, since it's from Digital Content Protection LLC, the docs are
> DRM'd
> (PDF-protected from copying).  So you can eyeball the key tables and
> test
> vectors that you need to implement the DRM, you just can't use them.
> 
> DRM, helping prevent... DRM.
> 
> Peter.
> 
> ---------------------------------------------------------------------
> The Cryptography Mailing List
> Unsubscribe by sending "unsubscribe cryptography" to
> majordomo at metzdowd.com
> 

---------------------------------------------------------------------
The Cryptography Mailing List
Unsubscribe by sending "unsubscribe cryptography" to majordomo at metzdowd.com