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A History of Copy Protection
GamerGirll1138 writes to tell us Next-gen has an amusing walk down memory lane with their history of copy protection. There have been some crazy schemes over the years to ensure that you paid for your software, everything from super-secret decoder rings to ridiculous document checks. "With bandwidth expanding and more and more games publishers exploring digital distribution, there's little doubt that we're entering a new phase in the history of copy protection and those who would defeat it. What's more, the demand for games as a chosen form of entertainment has never been higher. All this considered, it's impossible to believe that the cat-and-mouse game of piracy and copy protection will not reach new levels of intensity, with new technologies deployed on each side, and that some of them will surely create new hurdles for even those who simply wish to purchase and play the newest games. Ah, for the heady days of the code wheel."
http://www.next-gen.biz/index2.php?option=com_content&task=view&id=10800&Itemid=2&pop=1&page=1
An extremely useless article even by slashdot standards, but I remember two copy protection schemes that sucked even more:
Lenslock - used by a few 80s home computer games. I'm fairly certain it might have been a UK-only thing. It was horrible. You had to fold this crappy bit of plastic a certain way and hold it over a part of the screen. If you were lucky, and your TV wasn't too large or too small, you might be able to make out the decoded letters which you had to type in.
And then one we used at work: Parallel port dongles. I used to work in electronic CAD and all the software used this, the result being you needed 5 or more dongles all plugged in at the same time to do any useful work. In the end we got someone in the workshop build a kind of "dongle motherboard" where you could plug in multiple dongles more conveniently than having them hang out the back of the machine, and more importantly pull them out to swap between machines.
Happy days ... No, actually sucky days. I'm glad I use almost completely free software now.
Rich.
libguestfs - tools for accessing and modifying virtual machine disk images
I remember in the 1980s when game vendors started burning bad sectors into Atari 400/800 floppies on which they distributed their products. Their game's loader SW would try to read those sectors and abort if they weren't unreadable, thinking that pirates couldn't replicate them with just diskdup SW.
;) one bit (gotcha again >:P), but lots of honest people couldn't back up their games (which were sensitive to all kinds of transient EM, like paperclip collector magnets on desktops), and the vendors spent valuable time and money on worthless copy protection.
The Atari 810 floppy drive (the highest density storage available, like a 1TB HD is now, and the only game in town other than ridiculous tape drives, except for the extremely rare and stratospherically expensive 5MB Corvus HD) had a little potentiometer in its circuitboard controlling timing of the eletromagnetic signal waveform sent to the write head, that could be turned out of calibration to deliberately write a bad sector. So pirates would map the original's bad sector list, then copy the good sectors, then detune the pot, then write to the list of bad sectors - ruining them, then retune the pot and boot the copy.
Sure, that's pretty complex, voids the floppy warranty, and intimidates a lot of potential pirates. So instead, some people just stuck a disklabel to the edge of the target floppy, left the label sticking out of the drive, and grabbed that tab to jiggle the floppy while writing to each of the bad sectors - ruining them. Presto!
Besides, the pro pirates had the same mass floppy duplicators with the same programmable "write bad sector" circuitry that the original game vendors had, so the large, commercial pirates weren't fazed (pun intended
In fact, beating the copy protection was often more fun than the game. So around the world people were working to beat it, even if they never played the game again, but gave copies to friends just to show how ubergeek they were.
This cat & mouse game is in fact the exact model for all SW copy protection. It's become only a worse value waste for the SW producers, especially in content. They should use their only advantage, their earlier possession of the SW/content, to make big bucks at the first release, just like Hollywood does for movie premiere big weekends. Then let the pirates do their distribution work for free, and charge for support, customization, and subscriptions to upgrades. And build brands to sell their future releases.
Because "Don't Copy That Floppy" has been a losing battle, long before people would say "what's a floppy?"
--
make install -not war
Here's an example. I bought Maple 6 around five years ago. The retail box had a penguin on it, and advertised that it works on Linux. Cool. $140. No problem. So I get home, install it, and find out I have to get a license from Maple to run it. I go to the website, and later find out that the license is for Windows only. So I call Maplesoft, repeatedly, and after about a week I finally get a response. Pretty frustrating, but hey, in the grand scheme of things, a week is not a long time.
Several months later, after swapping a bad CDROM drive and upgrading RAM, the license key no longer works. So I call Maplesoft, again, and go through the same stupid hassle. The tech FINALLY gave me a machine-agnostic license after all the other crap she tried didn't work. If I had known, I would have asked for one in the first place.
Adding insult to injury, I had some outrageous charges on my phone bills because I didn't realize calling Canada carried "international calling" surcharges.
In the end, I didn't find Maple as useful as I expected. So the moral: I'll be more careful about spending money on proprietary software in the future.
That was the ProLok disk. It had a spot on it that had been heated with a laser, enough to fuse some of the oxide. The result was a small amount of disk space that could be read but not altered. The copy-check consisted of writing all zeroes to that area; verifying all zeroes; writing all ones; and verifying all ones. A disk with the laser spot would always produce at least one compare error.
The routine was hidden inside a really lame obfuscation scheme. It would read a section of encrypted code from the disk, XOR it byte by byte with a byte selected from a table, and store it in RAM. Then it would select another byte from the table and do the XOR again. And again, thirty or forty times. Each cycle would begin by altering the single-step and breakpoint interrupt vectors to point to an exit instruction.
If you went to the trouble of tracing your way down through all that, you were rewarded with a delicious irony: the ProLok disk was, itself, a copyright infringement. In order to do the write/read checks they had to insert hooks into the BIOS -- but that was not so easy in the small-RAM days when the BIOS executed directly from ROM instead of being shadowed out into RAM. Vault had to make its own BIOS, and did it by (drum roll) copying IBM's (rimshot). And they made an absurdly lame attempt to cover it up: they took some 800 bytes of the IBM Fixed Disk BIOS, added their hooks, then went through it and interchanged logical-shift-left and arithmetic-shift-left instructions wherever the MSB and carry were guaranteed to be zero (meaning both instructions did the same thing). So, disassemblies of the two BIOSes would look a LITTLE different...
Oh, the crack? A two-byte change on the disk, probably a back door they forgot to remove. Compuserve was the central clearinghouse for cracks in those days, and picked it up within a week.
AFAIK Vault's only client was Ashton-Tate, who used it on dBase III. The president of Vault was a guy with a law-enforcement background and a SWAT team mentality who fancied himself a mighty crime fighter, and when he was embarrassed by the quick crack, he boasted they were developing ProLok Plus, which would punish crackers by physically damaging the machine. Business customers were enraged, Ashton-Tate dumped Vault (which was expensive because they owned a one-third interest in it), and Vault was no more.
rj