

iBooks DRM has been cracked. - AndrewDucker
http://www.the-digital-reader.com/2012/02/23/ibooks-drm-has-been-hacked/

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DarkShikari
_I’ve always thought that DRM only remained unbroken so long as no hacker was
interested in breaking it_

This has always been true; why break the weak DRM on a low-quality 'Netflix'
stream when you can do an HDTV rip or even a Blu-ray rip?

But the instant you create exclusive content that everyone wants on such a
service, the DRM will be broken faster than you can say "DMCA".

The downside of this is it lets companies delude themselves (and others) into
thinking that their DRM is "secure", when in reality it is simply that nobody
cares about them.

~~~
jonny_eh
Now that Netflix has original exclusive content, can we look forward to
someone hacking the Netflix stream?

~~~
haakon
I've been told there are torrents of exclusive Netflix content.

~~~
daeken
Are they decrypted from the stream or screencapped and transcoded? If it's the
latter, then that's trivial and doesn't require breaking anything, it just
causes a good bit of degradation.

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tzs
There's one thing about cracking DRM that has me puzzled. Consider DRM on
music, for instance. Suppose we have a 4 minute song, stored as an MP3 with
DRM.

The ideal crack results in a 4 minute audio file, without DRM, that is the
same audio quality as the input MP3, and is about the same size.

If we didn't care about size, there would be an easy way to crack the DRM.
Just play back to music and capture the digital audio stream, and store that
as a WAV file, or compress it with a lossless compressor. That preserves the
audio quality, but the file is bigger.

If we are willing to give up some audio quality, we can do the above, but use
an MP3 encoder. That should get is back down to near the original size, but
the decoding and re-encoding as MP3 will cause some audio degradation.

Let's think about the MP3 format in an abstract way for a moment. Consider the
set of all possible 4 minute audio streams. Define a given stream as being
"perfectly representable" as an MP3 of bit rate B if there exists an MP3
encoding at a rate of B that decodes perfectly to that stream.

A general purpose MP3 encoder takes an input stream, and produces an MP3 file
that decodes to a perfectly representable stream that is close to the input
stream--ideally only differing in ways that people can't hear.

So here's the question--if the input stream to an MP3 encoder is perfectly
representable, why is the output usually a file that decodes to a _different_
perfectly representable stream?

It seems to me it should be possible to design an MP3 encoder with the
property that under the operation of encoding followed by decoding, the
perfectly representable streams are fixed points. I'll call such an encoder
"representation preserving".

With such an encoder, removing DRM from an MP3 file consists simply of playing
it back using whatever is normally used to play files with that DRM system,
capturing the digital output stream, and then re-encoding with a
representation preserving MP3 encoder. The result will by a DRM-free MP3 with
exactly the same quality as the MP3 you started with, and compressed to about
the same file size.

~~~
Peaker
The mathematical term you're looking for is Idempotence [1].

I'm speculating that the difficulty of such a feat depends on how many free
variables an encoder has to choose from.

For example, in the case of a compressor, there are probably quite a few
arbitrary choices that can be made at the compressor side that make little
difference to compression quality in general -- but may make reproducing the
exact same result difficult. The search-space might be very large.

I'll also speculate, though, that even if perfect reproduction is not
possible, a compressor that's designed to work on the digital output of a
decompressor of the same algorithm can probably be designed to do a better job
on that particular example.

[1] <http://en.wikipedia.org/wiki/Idempotence>

------
kristofferR
Offical site (requires TOR to be installed):
<http://tag3ulp55xczs3pn.onion/cgi-bin/ssi/index.shtml>

Webified link (doesn't require TOR): <http://tag3ulp55xczs3pn.onion.to/cgi-
bin/ssi/index.shtml>

~~~
Karunamon
Holy crap! I thought Requiem hadn't been updated in years!

Thanks for the links.

*edit

The onion site seems to have a heck of a time serving files. I've been trying
for an hour and have yet to get a valid zip. Some kind soul is seeding out a
torrent of all three archives (windows, mac, and source)

Try this:

magnet:?xt=urn:btih:a8f71c6c1b773a2f43850e4dae9189165a7ba0aa&dn=requiem-3.3.4&tr=udp%3A%2F%2Ftracker.openbittorrent.com%3A80%2Fannounce&tr=http%3A%2F%2Ftracker.istole.it%2Fannounce

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krig
I can confirm that yes, it has been cracked. Happily it is (as far as I know)
not yet illegal for me to remove DRM protection from books I've purchased,
although I'm sure that will change soon.

~~~
rmc
I think in the USA, the DMCA has made it illegal to break the copy protection
on copyrighted work?

It may or may not be against the iBook EULA, which might make you in breech of
contract, or make you guilty of using a computer system without agreement.

~~~
krig
I am not in the USA, but yes, I think you are correct about the DMCA.

Unfortunately, after looking into things it seems that the law in Sweden also
prohibits breaking DRM. There is a provision that if I am unable to otherwise
use the content, I am allowed to break the copy protection. However, the law
also prohibits making and spreading software that is capable of breaking copy
protection, so that sort of contradicts that escape route (since they can just
say that the illegal act was figuring out how to break the copy protection,
not the actual breakage).

In swedish, from the swedish government:
<http://www.sweden.gov.se/content/1/c6/05/07/29/96c6bfb1.pdf>

It's a sad state of affairs. :(

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jonny_eh
Great, now I honestly feel safe about buying from the iBookstore!

This can only lead to an increase in sales.

Did they not learn anything from the music industry? Sales have only gone up
since they scrapped DRM! (citation needed)

~~~
SoftwareMaven
I'm interested to see if this will be true for books as well. Taken in a
continuum of attention required, you start with music, then to movies,and
finally to books. As a result my ability to consume books is one to two orders
of magnitude lower than music. That seems like it could impact the economics
of discover-then-purchase that music "piracy"/"free marketing" has wrought.

Regardless, I think it will _always_ be good for the long tail authors.

~~~
vibrunazo
According to best-selling author Paulo Coelho, piracy's free marketing has
increased his sales: [http://thenextweb.com/2008/12/09/author-paulo-coelho-
support...](http://thenextweb.com/2008/12/09/author-paulo-coelho-supports-
piracy-share-to-get-revenue/)

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Vexenon
Surprised that websites are barely picking up on this, since the solution has
been out for roughly two weeks now. Requiem works great and it takes a matter
of seconds to complete, regardless of whether you're removing DRM from a book
or TV show.

Glad to see Brahms finally getting some much-deserved recognition.

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easp
Nice. My hope is that the market for eBooks (and Video) end up going the way
of digitally distributed music and ends up DRM free.

