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Defeating a 40-year-old copy protection dongle

dmitrybrant.com

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Re: Defeating a 40-year-old copy protection dongle

#61

Post by ryandrake »

GuB-42 wrote: post #31
catlikesshrimp wrote: post #9

Why wasn't (isn't) this more widely used? It was clearly more effective than a cdkey. I know there is cost associated with the hardware, but surely the costumer can cough 15 more dollars. The only reason I can think of is wanting as wide adoption before max revenue as possible. But then, this has never been too popular, not even for games!

Having to put a physical device on your parallel port at the back of the computer is kind of annoying, especially if every software you use has one. More common for games was to use the media itself for copy protection, using a variety of tricks to make copy more difficult. Other techniques involve printing some keys you have to enter using colors that don't render well in photocopies, or have you look at words a cer…

Makes me sad how many person-years of effort have been wasted over the years on futile dongle-engineering, copy-protection and DRM. They're pretty much all cracked. And the industry keeps insisting on trying!

Re: Defeating a 40-year-old copy protection dongle

#63

Post by zabzonk »

I think I remember hacking some of the copy-protection out of a version of Tetris using the Borland debugger. I definitely patched mouse support into a Chris Crawford "Battle of the Bulge" game using it (for my rather tricky platform). That was a good debugger, and probably the last one I have used much - prefer logging/printing for stuff I write myself.

I remember my Dragon 32 (6809, Color Computer clone) had a dongle you plugged into the joystick port to protect a really crap game - Jumping Knights? I never tried to defeat it.

Re: Defeating a 40-year-old copy protection dongle

#64

Post by antonvs »

foresto wrote: post #49
antonvs wrote: post #36

Earlier quoted context omitted.

> Many a crack back in the day was even more simple still, we'd just find and alter the right JE or JNE into a JMP and we're off to the races. I did that with dBASE III, which used ProLok "laser protection" from Vault Corporation - a signature burned onto the diskette with a laser. Back then, I found it amazing that Ashton-Tate actually spent money to contract with a copy protection company for something that could b…

> I was able to replicate that protection mechanism just by scratching a diskette with a pin. How did you figure out where to scratch it? Was the laser mark visible on the original disk, or did you have to read the code and orient based on the diskette's index hole?

I described two different scenarios: defeating the protection, and replicating it, e.g. to protect your own software without paying Vault for their "laser" protection.

Defeating the protection didn't involve knowing anything about the laser mark - as the comment I replied to described, it just involved changing a conditional jump to an unconditional one.

Replicating the protection involved causing minor damage on the diskette - the details don't really matter, laser, pin scratch, whatever - then formatting the disk, and registering the pattern of bad sectors created by the damage. A normal copy of the disk didn't replicate those bad sectors exactly, which made it possible to detect that the original disk was not present.

Re: Defeating a 40-year-old copy protection dongle

#65

Post by antonvs »

anyfoo wrote: post #56
antonvs wrote: post #36

Earlier quoted context omitted.

> Many a crack back in the day was even more simple still, we'd just find and alter the right JE or JNE into a JMP and we're off to the races. I did that with dBASE III, which used ProLok "laser protection" from Vault Corporation - a signature burned onto the diskette with a laser. Back then, I found it amazing that Ashton-Tate actually spent money to contract with a copy protection company for something that could b…

Was ist ever confirmed that it was in fact a laser? I wanted to make a trivia question out of this ProLok protection, because “lasers for copy protection” sounds just weird enough to potentially be a nonsense answer without context, but I couldn’t confirm that the holes were indeed made with lasers, and not with other means.

Good question. I don't know the answer, but I'm quite certain that it didn't really matter what mechanism was used to mark a diskette. Any damage would be equally strong as a way to detect copying.

Re: Defeating a 40-year-old copy protection dongle

#66

Post by charcircuit »

>The only evidence for the existence of this company is this record of them exhibiting their wares at SIGGRAPH conferences in the early 1990s, as well as several patents issued to them, relating to software protection.

There is also their webpage for ordering PC RPG II. The company address is a residential house.

https://web.archive.org/web/20010802153755/http://home.netco...

Re: Defeating a 40-year-old copy protection dongle

#67

Post by hinkley »

ruleryak wrote: post #7

Many a crack back in the day was even more simple still, we'd just find and alter the right JE or JNE into a JMP and we're off to the races. As the author found, the tough part is just finding and interpreting where and how the protection was implemented. If throwing the exe in a hex editor gave you access to String Data References (not always the case, but more common than not) then you'd just fail the check you wer…

There's a lot of things going on that lead to this.

One, the developers spend more time running this code than we do, and they have to get the program working before we can even use it. So any parts of the program that are hostile to the developers risks killing the entire project. Obfuscating the copy protection can hit a point where it makes bug fixing difficult.

Two, lack of training. If you, me, and Steve each have a bag of tricks we all use to crack games, whichever one of us figures it out gets bragging rights but the game remains cracked. Meanwhile Developer Dan has to be aware of all the tricks in all of our bags together if he wants to keep the three of us out. Only there's not three of us, there's 300. Or today, probably more like 30,000.

Three, lack of motivation, which is itself several different situations. There's a certain amount of passive aggression you can put into a feature you don't even really want to work on. You can lean into any of the other explanations to defend why your code didn't protect from cracking all that much, but it's a checkbox that's trying to prove a negative, and nobody is going to give you any credit for getting it to work right in the same way they give you credit for fixing that corner glitch that the QA people keep bitching about. Or getting that particle animation to work that makes the AOE spells look badass.

Re: Defeating a 40-year-old copy protection dongle

#68

Post by dpb001 »

ok123456 wrote: post #12
catlikesshrimp wrote: post #9

Why wasn't (isn't) this more widely used? It was clearly more effective than a cdkey. I know there is cost associated with the hardware, but surely the costumer can cough 15 more dollars. The only reason I can think of is wanting as wide adoption before max revenue as possible. But then, this has never been too popular, not even for games!

It was widely used in engineering software because the license cost was equivalent to a large fraction of an engineer's salary. Anyone who used AutoCAD back in the 90s can remember. When parallel ports were discontinued, they migrated to USB and network license servers.

A company I worked for in the mid-80’s used a PC based CAD package with this kind of copy protection. IIRC the cost of the software was about $5K, and engineers using it probably made around 50K/yr. This level of expense required a lengthy capex justification approval process. There was a category of users who didn’t need the software full time and since the software was tied to the dongle it was common to have the package installed on multiple workstations and borrow the dongle when needed.

The nature of our business was such that there was a lot of logic analyzers and signal tracing equipment in the lab and the dongle was reverse engineered and cloned after a couple of “where’d my dongle go” incidents.

Re: Defeating a 40-year-old copy protection dongle

#70

Post by charcircuit »

SecretDreams wrote: post #48
charcircuit wrote: post #43

Earlier quoted context omitted.

If a user gets ongoing value from software it makes sense for them to be willing to pay ongoing for that value. What users need is that the value they get from a product is more than the money they are trading for it. A one off license would be the result of a race to the bottom due to competition.

If I get ongoing value from my fully paid off car, should I keep paying the OEM? How about my house or my bike or my shoes? My toilet (huge ROI on this one)? My fridge?? Why do we feel that software gets to impose this ridiculous SaaS model? The only real answer is "because they can", not because it's helping anyone. Reality is that many modern software developments have plenty in common with designing a toilet. You…

I think it would be fair to keep paying for a car, house, bike, shoes, toilet, and fridge. If I'm still using such great products, why not reward the creators of them. But as a consumer I am also price conscious so if a competitor can offer an equivalent product for cheaper I will go with them.
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