Copy Protection

Diese Mail schrieb ich an die CdeB-Mailingliste als Antwort auf Chris' Man-on-the-Line Mail vom 9. Dezember 2004.

Ursprünglich wollte ich den Text als Brief an Ferryman Productions schicken, aber dann kam dieses „MotL“ wie eine Steilvorlage, und ich änderte mein Vorhaben und postete ihn auf die Mailingliste. Meine Intention war (und ist) nicht, eine Kopieranleitung zu geben (wie das geht, kann sowieso jeder rausfinden, der es rausfinden will), sondern zu zeigen, wie einfach der Kopierschutz überwunden werden kann und wie sinnlos er schon allein deshalb ist.

Veränderungen zu meinem dortigen Original: Zitate von Chris de Burgh sind kursiv gesetzt statt zeilenweise mit davorgesetzten >-Zeichen übernommen; minimale Veränderung des Linktextes zur CCC-Seite.


Hi Chris,

I heard you're reading the list :-)

I am not aware of the depth of the technology involved in copy protection

Well … I am. :-)

I was really happy when Alex Schestag gave me the „The Road To Freedom“ CD as a gift. As I usually do it with all other audio CDs, I put it into the DVD drive of my computer and listened to it. Only later I read from the back side of the CD case that this shouldn't be possible because the copy protection should prevent it. It seems that it didn't …

I became curious and wanted to find out whether (and if so) the copy protection works. Don't get me wrong, I'm not a cracker! I have even never made a copy of an audio CD before! Nevertheless I was able to make a copy of the original CD without any effort, any special devices or manipulations of the original CD. If you're interested, I can send it to you or put the songs in .wav, .mp3 or OggVorbis format to a password protected folder on my webspace.

I want to tell you how this is possible.

To understand my explanations, I first have to say that I use the operating system Debian GNU/Linux (and not Microsoft Windows). My PC is a Pentium III with 500 MHz, 320 MB RAM, a hard disk, a DVD drive (IDE), and an older CD burner (4x IDE). I listen to audio CDs via headphones connected directly to the DVD drive using the command line CD player software cdcd.

Here is, step by step, what I did:

  1. I put the original CD into the DVD drive and a CD-recordable into the burner.
  2. Then I used the console program cdda2wav to copy the tracks to my hard disk in the following way: cdda2wav -v255 -D0,0,0 -B -Owav (-v255 = print verbose information about the running process on highest level; D0,0,0 specifies my DVD drive as source device; -B copies each track into a separate file; -Owav specifies the file type for the output). To my surprise all tracks were copied to my hard disk without any trouble.
  3. After that I took a look at the files on the disk. For each track I found the *.wav file and an *.inf file. Additionally, I found the files audio.cddb and audio.cdindex. I opened the file audio_01.inf to see over it. It contains the following lines:
#created by cdda2wav 1.10_linux_2.4.18_i686_i686 11/20/04 12:21:01
#
CDINDEX_DISCID= 'TaVoAZvRjFl_1hcWPVPsBrQfIRQ-'
CDDB_DISCID=    0xa612a00c
MCN=
ISRC=           GB-GRM-04-00001
#
Albumtitle=     'COPYXA'
Tracktitle=     'Track 01'
Tracknumber=    1
Trackstart=     0
# track length in sectors (1/75 seconds each), rest samples
Tracklength=    17060, 0
Pre-emphasis=   no
Channels=       2
Copy_permitted= no
Endianess=      little
# index list
Index=          0
Index0=         -1

I guess the line „Copy_permitted= no“ shall be the „copy protection“ … So, if the player or copy software you use executes this command, it will not play or copy the CD, and if not, there will be no copy protection at all. I hope you did not have to pay too much for that „technology“.

By the way, it would have been nice if you had inserted the real album title and the track titles into these files. :-)

  1. The next step was to burn these files on the CD-R. I used the same command line program I normally use for burning data CDs, but with different parameters: cdrecord -v dev=0,1,0 -dao -useinfo *.wav (-v = print out info­mation about the process verbosely; dev=0,1,0 = specifies my burner as target; -dao = disk at once mode; -useinfo = use *.inf files to overwrite audio options; *.wav = source files). This process also passed through within about 12 minutes without any trouble.
  2. At last I took the original CD out of the DVD drive and put the just burned CD into it. It wasn't quite a surprise that the player software was able to play it completely and in the same quality as the original CD.

Conclusion: The copy protection you use on this album does not work, because it depends on the ability of the used software to execute one special command in the *.inf file of each track.

The shiny ring on the data side of the CD either seems to be just a mere windowdressing or another useless try to make the disk unreadable to CD/DVD drives or player software. The player program cdcd is not able to recognize the end of the last track immediately; it stops only about two minutes later. This could be an effect of this ring, but I'm not sure. cdda2wav didn't seem to notice this at all, for it found the correct end of the last track. When I play the copy with cdcd, it stops immediately after the last track.

Again, I want to make clear that I am not a cracker. I only wanted to prove that this copy protection does not work. I do respect the work and the right of any artist to earn money with it, and although I really don't belong to those who are called rich I'll carry on buying the albums I'd like to listen to like I always did.

from earlier answers on Man On (the) Line about downloading and so on, I'm very much against it. It's piracy and it's theft. But copyright protection in effect means exactly that you can't copy off a disc, as I understand it. To be honest, anything that protects the artist in a way they like to make the music, and what it costs them to make the music, I'm very much a supporter of.

OK, let me drop a few lines about copy protection in general; in my opinion this is the wrong way to save the rights of artists because of the following reasons:

If copy protection works, customers will not even able to make a private copy for daily use to save the original (what is basically allowed) or to play it on drives or players that cannot play the original CD. – If it doesn't work, like in this case, nothing is won at all.

In any case customers have to pay more for a protected than for a non protected CD. So they have to pay additionally for being restricted!

In Germany customers have to pay a fee on each CD/DVD-recordable and each CD/DVD-player and -burner to the GEMA. With that fee they buy the right to make private copies of CDs/DVDs they had paid for. Doesn't this money reach the artists?

This GEMA wants people who copy music to be seen on the same level as criminals like child abusers or violent nazis. Do you agree to that?

By the way: In 1997, the price for an audio CD in Germany usually was between DM 12 and 20. Now it is between 15 and 25 Euro (DM 30 to 50). In the same time the income of people didn't grow much or even went down, and there are more and more people without a job (unfortunately I am one of them). Taking these facts into account I find it understand­able that people copy music instead of buying it (although, as I mentioned before, I'm not one of those).

Of course it is unfair to criticise without making constructive suggestions. In an article dated March, 30th, 2004 the German Chaos Computer Club e. V. stated:

Peer to peer networks have been proven as a perfect way of distribution - only a reasonable paying system is missing. The music industry missed the train to the internet. The listeners have found their own ways in up to date technics to satisfy their wishes. In the same time the music industry continued taking care about their own benefice. But a lot of listeners are willing to pay the artists for their work. Therefore new ways must be found to let them get a fair payment.

(partly translation).

I think the labels should better search for such new ways of distributing their music instead of trying to restrict their customers.

Besides, I can assure you that the professional pirates don't care about all these efforts of the music industry and keep on cracking and copying anyway.

Greets, Sabine