Virgil was there two years ago when Dmitri Sklyarov was arrested and led away in handcuffs at Def Con 9. He's not in handcuffs now, but in speaking to me, he had to stop and think about everything he said, and every third answer was "I really shouldn't talk about that."

The DMCA is largely to thank for that. Section 1201 states that no one "shall circumvent a technological measure that effectively controls access to a work," and that no one "shall... offer to the public... any technology" to do so. Blackboard Inc., whose card system is called the Blackboard Transaction System and known to end users under various names, uses a network of card readers and a central server, and they communicate over RS-485 and Internet Protocol -- using, or so they apparently claim, measures that effectively control access.

For the record, none of what I learned about the Blackboard technology was from him or Acidus after the restraining order was sent. I spoke to other people, who have not been served with a restraining order. Google has a less enlightening mirror of the slide titles from this weekend's PowerPoint presentation and a more enlightening mirror of Acidus's "CampusWide FAQ" from last July. And, most enlightening of all, this mirror has an updated version with details on what they figured out how to do and what their talk was going to be about (click "CampusWide" for the text description, the PowerPoint slides, and Acidus's timeline of the last year).

At many schools, Blackboard's system is the ID: you swipe your card for your meal plan at the cafeteria, to get into your dorm, maybe even to get your final exam.

A swipe at a vending machine will get you a soda -- a money transaction from your campus debit account. When you use a swipe to do laundry and make copies, money has to be involved. Blackboard even notes that they can set up a merchant network on- and off-campus: "a cashless, safe, and secure way to transact on and around campus while offering parents the assurance that their funds will be spent within a university-approved network." (Emphasis added. Maybe readers who go to schools that use such a system can expand on how that system is used.)

The kicker, of course, is that this network is not very secure, or at least Blackboard doesn't think it's as secure as... well, as lawyers. One anonymous Slashdot submitter wrote that: "The authentication system is so weak that [Virgil and Acidus] have been able to create a drop in replacement for the CampusWide network debit card readers used on coke machines on campus."

Virgil couldn't provide me any details about what he had learned about the system. Based on the mirrors, it looks like a man-in-the-middle replay attack -- which is a pretty simple attack, repeating messages sniffed over the RS-485 protocol, or even over IP -- can have effects like convincing a Coke machine to dispense free product. Or, it's claimed, the attacker can create a temporary card, with no name attached, and free money in its account. Hmmmmm.

Or, more ominously, someone else's identification might be sniffed, and then replayed from a security terminal. If a thief gained entrance to a building by sending the message "open the door, my name is John Doe," the real John Doe might be sorely inconvenienced the next morning.

So, if you're a student at a school that uses Blackboard, do you feel more secure now that the DMCA has tried to stop you from learning about its security flaws?

If you're a parent putting money into a Blackboard-based debit account, do you feel more confident of its safety now that this information is ostensibly hidden?

This card system has been installed on many campuses and its roots go back almost twenty years. My guess is that replacing the card-reading hardware would be necessary to improve the security of these devices. Obviously, Blackboard would be hard-pressed to replace thousands of hardware devices at all its locations, even if they'd started in late 2001 when Acidus claims he called to tell them of the flaws he'd found (and "was blown off").

So, assuming that's not possible -- is the DMCA a viable tool to ensure security?

P.S. Virgil tells me that he has a good lawyer. They are scheduled to argue on Thursday that the restraining order not be made permanent. Slashdot will keep you apprised of what happens in our Slashback stories... stay tuned.

P.P.S. Update: 04/15 02:30 GMT by J : Now online are the restraining order, which just lists the six things that Acidus and Virgil are not to do, and the more detailed Complaint. Now that these are available, as Declan McCullagh points out, it turns out the DMCA was only in the lawyers' threatening letter and not considered as part of the Complaint itself. I'm not sure why it would be included in the letter -- some of the language of the Georgia Computer Systems Protection Act is similar, and who knows, Section 1201 might be mentioned later on, as this case progresses. Maybe the lawyers are just keeping their options open. Meanwhile, I love this part of the Complaint:

"Mr. Hoffman openly acknowledges on his website that 'I am a hacker.' His website then defends the process of hacking. See Exhibit B."