4 ms·

very impressive write-up, sir! i'm not super-proud of it, but i got started in programming by breaking the copy protection of dos games. i ran the game on my c

very impressive write-up, sir! i'm not super-proud of it, but i got started in programming by breaking the copy protection of dos games. i ran the game on my color monitor and borland's turbo debugger on the monochrome one, and single-stepped my way through the code until i had figured it out. then i'd use the norton utilities to find a particular code string in the executable on disk, and patch it with my NOP'ed out version. twenty years later and i still have the byte patterns of many 8086 machine language instructions memorized. this would have just been harmless fun, except i posted my cracks on the BBSes of the day. well, i was young.

deleted 17y ago
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noonespecial 17y ago
Wow. Nostalgia so strong I got vertigo. I now humbly submit to HN a picture of myself circa 1989, doing exactly this to the game "Spacewar". http://www.jonandkarrie.com/images/prints_028-2.jpg http://www.jonandkarrie.com/images/prints_028-2.jpg I know why you might want to post the fruits of your labors to BBS's. When I tried to boast of my accomplishments to friends of the day, I couldn't get them past "you can have two monitors on the same computer and they both go!?"
- allenbrunson 17y ago
  heh! i had that exact same (cracked) game! it didn't hold my interest for very long, though. i could always tell the difference between the companies that rolled their own weak-ass protection schemes in-house, and the ones who ponied up for the good stuff, like softguard. the simplest game i ever broke, before i even owned turbo debugger, was the dos version of rampage. all i had to do was NOP out three calls to INT 10h, the bios direct disk interrupt, and it wasn't able to 'see' the corrupted sectors on its copy-protected floppy anymore. in the mildly difficult range was this flight simulator i cracked for a friend. i found the protection function that i wanted to NOP out and wrote down the sequence of bytes that needed to be changed. but when i searched the executable with norton, those bytes weren't found! further exploration revealed that the programmers had applied some weak XOR-style "encryption" to the copy protection routine i was trying to get rid of. i had to write a little utility in C to break that one. i tried to break several of the sierra games, like king's quest. but they were using their own in-house interpreter, so trying to crack it with an 8086 assembler was approaching the problem at the wrong level of abstraction. i couldn't do it. i never did manage to get any of the softguard games, either. they were doing really wicked things like using the INT 1 and INT 3 interrupt vectors as scratch space. they knew perfectly well that people like me needed those interrupts to be intact for our debuggers to work. i tried redirecting the first 100 calls to a different area of memory, but they were really fiendishly thorough. i gave up. bet you've got some good stories, too. hint hint.
  - noonespecial 17y ago
    Most of my pc exploits involved searching for days to find just the right place to set 1 equal to 1, doing it and declaring victory. I spent a huge amount of time on my Amiga tweaking disk copy algos to foil those rotten floppies that had tiny holes physically burned or punched into the medium. After you got the damn thing to copy, then you had to hunt through the executable to find out what behavior the program expected from the disk drive when it encountered the hole and put in a jump to skip this. I remember my 13 year old self exclaiming "they use the drive error as the key?! That's just diabolical!"
- johnyzee 17y ago
  Great picture. Is that the backside of an Amiga 500 on the bottom shelf to the right? [Edit] You already answered that. I had a 1200 bps modem for that rig around the same time and would sit around on BBS'es for hours.
  - noonespecial 17y ago
    Ohh, good eye! The monitor on my left was my Amiga monitor as well. My 1200 baud hayes is standing on edge between that monitor and my main pc monitor. Those were good times. Damn I feel old.
- NateLawson 17y ago
  I see you had a C64C on the lower right shelf. Perhaps you moved to the PC too quickly? :)
  - noonespecial 17y ago
    Damn, you're completely right. I thought that was my amiga500 but on a closer look, its the c64 I got when I was 10. I lost my original in a fire when I was 9 and got a -C as a replacement. Shortly after, I got the amiga and seldom looked back. I didn't move to pc too quickly, I moved to amiga. Apologies to johnyzee, there is an A500 around there somewhere, but Nate's right. Look at the round 488 connectors in the middle. Thats a 64-c alright. I was trying for the life of me to figure out why my a500 would have been down there on that cart looking so disused.

deleted 17y ago

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noonespecial 17y ago

Wow. Nostalgia so strong I got vertigo. I now humbly submit to HN a picture of myself circa 1989, doing exactly this to the game "Spacewar". http://www.jonandkarrie.com/images/prints_028-2.jpg http://www.jonandkarrie.com/images/prints_028-2.jpg I know why you might want to post the fruits of your labors to BBS's. When I tried to boast of my accomplishments to friends of the day, I couldn't get them past "you can have two monitors on the same computer and they both go!?"

allenbrunson 17y ago
heh! i had that exact same (cracked) game! it didn't hold my interest for very long, though. i could always tell the difference between the companies that rolled their own weak-ass protection schemes in-house, and the ones who ponied up for the good stuff, like softguard. the simplest game i ever broke, before i even owned turbo debugger, was the dos version of rampage. all i had to do was NOP out three calls to INT 10h, the bios direct disk interrupt, and it wasn't able to 'see' the corrupted sectors on its copy-protected floppy anymore. in the mildly difficult range was this flight simulator i cracked for a friend. i found the protection function that i wanted to NOP out and wrote down the sequence of bytes that needed to be changed. but when i searched the executable with norton, those bytes weren't found! further exploration revealed that the programmers had applied some weak XOR-style "encryption" to the copy protection routine i was trying to get rid of. i had to write a little utility in C to break that one. i tried to break several of the sierra games, like king's quest. but they were using their own in-house interpreter, so trying to crack it with an 8086 assembler was approaching the problem at the wrong level of abstraction. i couldn't do it. i never did manage to get any of the softguard games, either. they were doing really wicked things like using the INT 1 and INT 3 interrupt vectors as scratch space. they knew perfectly well that people like me needed those interrupts to be intact for our debuggers to work. i tried redirecting the first 100 calls to a different area of memory, but they were really fiendishly thorough. i gave up. bet you've got some good stories, too. hint hint.
- noonespecial 17y ago
  Most of my pc exploits involved searching for days to find just the right place to set 1 equal to 1, doing it and declaring victory. I spent a huge amount of time on my Amiga tweaking disk copy algos to foil those rotten floppies that had tiny holes physically burned or punched into the medium. After you got the damn thing to copy, then you had to hunt through the executable to find out what behavior the program expected from the disk drive when it encountered the hole and put in a jump to skip this. I remember my 13 year old self exclaiming "they use the drive error as the key?! That's just diabolical!"
johnyzee 17y ago
Great picture. Is that the backside of an Amiga 500 on the bottom shelf to the right? [Edit] You already answered that. I had a 1200 bps modem for that rig around the same time and would sit around on BBS'es for hours.
- noonespecial 17y ago
  Ohh, good eye! The monitor on my left was my Amiga monitor as well. My 1200 baud hayes is standing on edge between that monitor and my main pc monitor. Those were good times. Damn I feel old.
NateLawson 17y ago
I see you had a C64C on the lower right shelf. Perhaps you moved to the PC too quickly? :)
- noonespecial 17y ago
  Damn, you're completely right. I thought that was my amiga500 but on a closer look, its the c64 I got when I was 10. I lost my original in a fire when I was 9 and got a -C as a replacement. Shortly after, I got the amiga and seldom looked back. I didn't move to pc too quickly, I moved to amiga. Apologies to johnyzee, there is an A500 around there somewhere, but Nate's right. Look at the round 488 connectors in the middle. Thats a 64-c alright. I was trying for the life of me to figure out why my a500 would have been down there on that cart looking so disused.