81–90 of 135 posts
Very clever and great article! But it sounds pretty easy to write a cracker for it: Just rewrite the machine code to jump over the check. Or did I miss anything? Edit: Guess it depends on the details and amount of "obfuscation" that he mentions.
Slightly off-topic, but since when were floppies referred to as "disc", as opposed to "disk"? I thought it was from Diskette? Is it a language / region thing? Optical discs were "disc", but at least growing up in the UK in the 80s/90s with DOS/Windows, I'm pretty certain I remember them always being "disk" for floppies? Am I misremembering?
I've kinda wondered if the "c" spelling comes from "discus", i.e. https://en.wikipedia.org/wiki/Discus_throw I have absolutely no evidence for or against this though.
Who recalls the provenance of this old legend about the fellow who challenged his pal to decode a certain floppy? It was a bog-standard DOS boot disk (IIRC) that he could put in his machine and boot normally. But his pal put it in his computer and... nothing doing, no boot. Analysis of the floppy availed not. The challenge went unmet. What did our hero do to make the floppy? .esrever ni nups evird eht os ytiralop eti…
My favorite copy protection was on some games I had (I want to say they were Microprose games? But I could be wrong) where they would cut the hole in the disk just slightly bigger, and then take advantage of the fact that in DOS you could talk directly to the hardware to convince the read head to go just a little too far. Then it could read the magic 41st track to load the game, but no disk copy program could copy it…
My favorite one is the spiral tracks on the Apple II, which were possible because all phases of the stepper motor were directly accessible on the controller, so you could move the stepper motor in quarter tracks. Impossible to copy unless you reproduce the head movements at the right time.
Earlier quoted context omitted.
Nah. I remember those days. Programs that could read/write/discover more tracks than the standard amount were widely available.
There was a similar situation with CDs where you could overprovision data that existed past the technical limit of useable range. I think that's was utilized in NINs Year Zero ARG experiment.
Earlier quoted context omitted.
My favorite one is the spiral tracks on the Apple II, which were possible because all phases of the stepper motor were directly accessible on the controller, so you could move the stepper motor in quarter tracks. Impossible to copy unless you reproduce the head movements at the right time.
Interesting! How did it not also affect reads, though?
I'm curious what tricks people use nowadays for software copy protection? Are dongles still a thing? Have people given up on the idea of software protection? (SaaS is probably the best kind of protection if you don't take it too literally)
I'm curious what tricks people use nowadays for software copy protection? Are dongles still a thing? Have people given up on the idea of software protection? (SaaS is probably the best kind of protection if you don't take it too literally)
Back in the 1980's I think there were a lot of interesting schemes. The solution was to just get an updated version of copy2pc or copywrite and they would have a fix. But I remember a few schemes that were interesting workarounds. One was the hole in the disk, one was a laser-burned dot on the disk. I recall with the hole in the disk - the software would try to read and if it succeeded it was a copy. The second one w…
I played the modern version (Leisure Suit Larry Reloaded) a bit but couldn't complete the age verification because it relied on the American history and pop culture too much. Had to shamefully google the answers.