November 20, 2017

Archives for 2005

Is DRM Good for You?

Randy Picker, a principled DRM (copy protection) advocate, had an interesting comment on one of my prior posts about the Sony incident. Here’s the core of it:

Assume for now that you are right that DRM leads to spyware; all that means is that we need to figure out whether we should or shouldn’t favor active protection/supervision environments.

That gets us to the central point: namely the fact that consumers don’t want it doesn’t tell us anything about whether it is in the joint interests of consumers and producers. I spent the morning writing my exam and then will have to grade it after the students take it (no grad student graders for law profs). By far and away the worst part of the job, and I certainly don’t want it as part of the job, but that doesn’t mean that it isn’t jointly sensible.

Putting that point slightly differently, consumers may gain more from a DRM world than they would from whatever alternative world emerges without DRM; those subject to restrictions rarely want them but restrictions are frequently welfare maximizing; the fact that one party would like to get rid of the restrictions tells me little (nothing, probably) about whether the restriction is in the joint interest of the parties to the transaction.

It’s true in principle that an arrangement can be unwanted but ultimately good for those on whom it is imposed; but I don’t think that observation matters much in the specific case of CD DRM.

To understand why, let’s look at a case where a similar argument has traditionally worked: copyright. Copyright can be understood as an agreement among all of us that we will not infringe. Even though each of us individually would prefer to use works without paying, we understand that if we all refrain from infringing this increases incentives for authors, leading to the creation of more works we can enjoy. By making and keeping this copyright deal with each other, we come out ahead. (That’s the theory anyway. We all know what happens when the lobbyists show up, but work with me here, okay?)

One of the practical problems with this kind of deal is that each individual can gain by defecting from the deal – in the case of copyright, by infringing at will. If enough people defect, the deal could collapse. This danger is especially acute when it’s technologically easy to defect. Some people argue that this is happening to the copyright deal.

Anyway, what Randy is suggesting is that there might be a similar deal in which we all agree to accept some kind of DRM in order to boost incentives for authors and thereby cause the creation of more works than would otherwise exist. I think that if we weigh the costs and benefits, that would be a bad deal. And I’m especially sure it’s a bad deal for CD DRM. Let me explain why.

First, it turns out to be easy technologically to defect from the CD-DRM deal. Experience with the copyright deal teaches us that when it’s easy to defect, many people will, whether we like it or not.

Second, the costs of the CD-DRM deal seem much clearer than the benefits. Allowing spyware-DRM on our computers will open loopholes in our anti-spyware defenses that will foster more spyware infections. And as we have seen already, spyware-DRM will itself expose us to security risks. That’s the cost side. On the benefit side, we have only the dubious premise that CD-DRM might boost record sales. The costs are more certain, and larger.

The best argument against the CD-DRM deal, though, is that it is inferior to the copyright deal. If we’re going to make and keep a deal of this general type, the copyright deal is the one to pick. Compared to the copyright deal, the CD-DRM deal is a loser: costs are higher, benefits are the same at best, and the deal is just as easy to defect from. If we can’t keep the copyright deal, then we won’t be able to keep the CD-DRM deal either. But more to the point, we shouldn’t make the CD-DRM deal in the first place.

I’ve looked here at the specific case of DRM for CDs, but I think the same argument holds for other types of DRM as well. Leaving aside the mythical side-effect-free DRM systems and perfectly just legal regimes that some DRM advocates dream about, and looking instead at DRM systems and legal rules that could actually exist and how they would work in practice – as I am sure Randy and other principled DRM advocates would want us to do – the available DRM deals look lousy. Certainly they look worse than the original copyright deal.

Now I’m not arguing here that the current copyright deal is perfect or even close to perfect. The copyright deal is under stress and we need to keep thinking about how we might improve it or how we might renegotiate it to work better in the digital world. I’m not certain what the best deal would look like, but I’m pretty sure that it won’t try to lock in any kind of DRM.

G-Men Called on W-Hats for WMVD

[Despite our recent focus on the SonyBMG CD flap, our mandate here at Freedom to Tinker covers infotech and policy generally. So I hope any Sonymaniacs in the audience will forgive me for posting about something else today. (If you need a Sony fix, Bruce Hayden can help.) Regularly scheduled Sony-related programming will resume next week.]

There’s a fascinating story going around about the intersection between virtual worlds and real-life law enforcement. (I have written twice before about this topic.) It started in a virtual world called Second Life, which has 70,000 or so members. There’s a group of in-world characters calling themselves the W-Hats. Stories in the Second Life Herald – a foulmouthed but apparently somewhat trusted virtual newspaper about Second Life – depict the W-Hats as a gang of racist thugs. (The rest of the story I tell here is based on the Herald’s reporting.)

One of the cool things about Second Life is that players can create new kinds of objects, by writing small programs in a special scripting language to describe how the objects should behave, and then launching objects into the world.

Things got really out of hand when the W-Hats created a doomsday device. It looked like a harmless little orb, but it was programmed to make copies of itself, repeatedly. The single object split into two. Then each of those split, and there were four. Then eight, and sixteen, and so on to infinity.

Okay, not exactly to infinity but to billions of copies (after thirty-some generations of splitting), at which point the servers running Second Life crashed, and the whole virtual world was knocked off-line. The W-Hats had created a Weapon of Mass Virtual Destruction (WMVD).

The WMVD was detonated more than once, and on at least one occasion Linden Lab, the company that runs Second Life, contained the damage by taking parts of the world offline as a kind of virtual firebreak.

Last week at an in-world holiday party, Philip Linden, the character played by Linden Lab CEO Philip Rosedale, mentioned that the company had called the FBI about the attacks and had turned over the names of some players. Others at the party reportedly praised the action. But was this justified? Should the FBI get involved in this mess?

It seems to me that they should. A WMVD of this sort is just a fancy denial of service attack, and a deliberate denial of service attack against a large network service looks to me like a crime. It’s possible that the first attack wasn’t meant to crash Second Life – though even if not deliberate it was certainly reckless – but subsequent attacks could only have been intended to cause a crash.

There is some indication that Linden Lab may have banned at least one player temporarily because of the attacks, but there is a limit to the effectiveness of in-world punishment. As James Grimmelmann has argued, the worst punishment available in-world is exile from the world – try to impose a stronger penalty on someone and he will simply exile himself by leaving the virtual world permanently. Real-world punishments can be worse than exile and so stronger deterrence is available in the real world. When stronger deterrence is needed, real-world punishment may be the only option.

Some have argued that players shouldn’t be punished for doing things that the world’s coding allows them to do. But that seems to me to be the wrong rule. For one thing, that’s not how things work in the real world, where you can commit all manner of crimes without violating the laws of physics. And it’s just wrong to think that the virtual world can be coded in a way that allows everything good but prevents everything bad. Any virtual world (if I may be forgiven for that phrase) that is complicated enough to be interesting will probably enable some undesired behavior.

It will sometimes be necessary, then, to appeal to real-world law enforcement to handle bad acts in virtual worlds. In general, there are lots of caveats here – for example, in some worlds, in-world fraud or murder is considered just part of the game; and world-builders shouldn’t run to the FBI over minor problems. But the particular case before us seems like an easy one: the FBI should investigate and, at the very least, use its power to intimidate the perpetrators into behaving better.

Make Your Own Copy-Protected CD with Passive Protection

Here’s a great gift idea just in time for the holidays: Make your friends and relatives their very own copy-protected CDs using the same industrial-grade passive protection technology built into XCP and Macrovision discs.

Passive protection exploits subtle differences between the way computers read CDs and the way ordinary CD players do. By changing the layout of data on the CD, it’s sometimes possible to confuse computers without affecting ordinary players — or so the theory goes. In practice, the distinction between computers and CD players is less precise. Older generations of CD copy protection, which relied entirely on passive protection, proved easy to copy in some computers and impossible to play on some CD players. For these reasons, copy protection vendors now use active protection — special software designed to block copying.

Discs with XCP or Macrovision protection employ active protection in conjunction with a milder form of passive protection. You can create your own CD with exactly the same passive protection by following a straightforward five-step procedure. I’ll describe the procedure here, and then explain why it works.

What you’ll need:

  • A computer running a recent version of Windows (instructions are Windows-specific; perhaps someone will write instructions for MacOS or Linux)
  • Nero, a popular CD burning application
  • CloneCD, an advanced disc duplication utility
  • Two blank recordable CDs

Step 1: Burn a regular audio CD

Start Nero Burning ROM and create a new Audio CD project. [View] Add the audio tracks that you want to include on your copy-protected disc. [View] When you’re ready to record, click the Burn button on the toolbar. In the Burn tab, make sure “Finalize disc” is unchecked. [View] Insert a blank CD and click Burn. Be careful not to infringe any copyrights! For loads of great music that you can copy legally, visit Creative Commons.

Step 2: Add a data session to the CD

Start another Nero compilation, this time selecting the “CD-ROM ISO” project type. In the Multisession tab, make sure “Start Multisession disc” is selected; and in the ISO tab, make sure Data Mode is set to “Mode 2 / XA”. [View] Add any files that you want to be accessible when the CD is used in a computer. You might include “bonus” content, such as album art and lyrics. [View] For a more professional effect, consider adding the installer for your favorite spyware application and creating an Autorun.inf file so it starts automatically. When you’re finished, click the Burn toolbar button. Insert the audio CD you created in Step 1, and click Burn. [View] Nero should warn you that the disc you’ve inserted is not empty; click Yes to add your data files as a second session. [View]

At this point, you’ve created a CD that contains both audio tracks and data files. The data files you put on the CD should be visible in Windows Explorer (in My Computer, right click the CD icon and click Open) and the audio tracks should be rippable with your favorite audio player. To add passive copy protection, you’ll need to modify the layout of the data on the disc so that the audio tracks are more difficult to access.

Step 3: Rip the CD as a CloneCD image file

Make sure the CD you just created is still in the drive and start CloneCD. Click the “Read to Image File” button. Select your drive and click Next. Choose “Multimedia Audio CD” and click Next. [View] Select an easy to find location for the image file and click OK to begin ripping.

Step 4: Modify the image file to add passive protection

The CloneCD image you created in step 3 actually consists of three files with names ending in .CCD, .IMG, and .SUB. The .CCD file describes the layout of the tracks and sessions on the CD. You’ll edit this file to add the passive protection.

Start Windows Notepad and open the .CCD file. Modifying the file by hand would be tedious, so I’ve created an online application to help. Copy the entire contents of the file to the clipboard and paste it into this form, then click Upload. Copy the output from the web page and paste it back into Notepad, replacing the original file contents. [View] Save the file and exit Notepad.

Step 5: Burn the modified image to create a copy-protected CD

Insert a blank CD and start CloneCD again. Click the “Write From Image File” button. Select the image file you modified in step 4 and click next. Select your CD recorder and click Next. Select “Multimedia Audio CD” and click OK to begin burning. [View]

That’s it! You’ve created your very own copy-protected CD.

Now it’s time to test your disc. If everything worked, the files from the data session will be visible from My Computer, but the audio tracks will not appear in Windows Media Player, iTunes, and most other mainstream music players. The CD should play correctly in standalone CD players.

How it works. To see how this form of passive protection works, you can examine the layout of the CD you created. Start Nero and select Disc Info from the Recorder menu. You should see something like this:

(The exact number of tracks you see will depend on how many songs you included.)

Notice that the tracks are grouped into two sessions — essentially two independent CDs burned onto the same disc. Unprotected CDs that combine audio and data files contain audio tracks in the first session and a single data track in the second. The only difference in the passive protected CD you just created is that the second session contains two tracks instead of one.

You added the extra track (shown in yellow) when you edited the disc image in step 4. This simple change makes the audio tracks invisible to most music player applications. It’s not clear why this works, but the most likely explanation is that the behavior is a quirk in the way the Windows CD audio driver handles discs with multiple sessions.

For an added layer of protection, the extraneous track you added to the disc is only 31 frames long. (A frame is 1/75 of a second.) The CD standard requires that tracks be at least 150 frames long. This non-compliant track length will cause errors if you attempt to duplicate the disc with many CD drives and copying applications.

Caveat emptor. Yes, your copy-protected CD is “industrial strength” — XCP and Macrovision employ exactly the same passive protection — but even the pros have their limitations. There are many well-known method for defeating this kind of passive protection, such as:

  • Enhanced software – Advanced CD ripping programs avoid the Windows CD audio driver altogether and communicate directly with the CD drive. Thus, programs such as EAC are able to rip the tracks without any difficulty. – Better CD copying applications, including Nero, support a recording mode called Disc-at-Once/96; this lets them create an exact duplicate of the protected disc even though the last track has an illegal length.
  • Other operating systems – The discs can be ripped with standard software on Macs and on Linux systems. These platforms don’t suffer from the limitation that causes ripping problems on Windows.
  • Magic markers – The famous magic marker trick involves carefully drawing around the outer edge of the CD. This blocks out the second session, allowing the disc to be ripped and copied just like an unprotected CD.

And of course, at any time Microsoft could fix the Windows quirk that is the basis for this technique, rendering it completely ineffective.

Despite these limitations, who wouldn’t enjoy finding a homemade copy-protected CD in their stocking? They’re a great way to spread holiday cheer while preventing anyone else from spreading it further.