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NFG Forums => X68000 Software => Topic started by: eidis on July 10, 2014, 06:07:48 AM

Title: Major release: Bomber Man. Cracked by Eidis cracking group.
Post by: eidis on July 10, 2014, 06:07:48 AM
 Ladies and Gentlemen,

Today marks another milestone. The protection of this awesome game has finally been defeated and now we can finally enjoy it from HDD.

I would like to dedicate this release to Caius and Lydux ! Thanks guys ! You both made it happen ;)

Bomber Man
http://nfggames.com/x68000/Games/ProjectUnsubst/BomberMan.Lzh (http://nfggames.com/x68000/Games/ProjectUnsubst/BomberMan.Lzh)

Here is the procedure which was used:

Offset #DE
Change 67F2 to 4E71

Offset #100
Change 66D0 to 4E71

Keep the scene alive !
Eidis
Title: Re: Major release: Bomber Man. Cracked by Eidis cracking group.
Post by: caius on July 10, 2014, 07:49:04 AM
Ah, thanks for your dedication but this is a good one from you, Eidis!Awesome job!I presume you patched with two NOP instructions the floppy media checks in the main executable 'BM.X'?Did you use the XM6 debugger to discover this?As I said, this game required a whatever floppy inserted in order to boot into game.
Title: Re: Major release: Bomber Man. Cracked by Eidis cracking group.
Post by: eidis on July 10, 2014, 05:16:17 PM
 Hi Caius !

That is correct. 4E71 (NOP) is your friend ;)

I used the almighty XM6 Pro-68k by M.I.J.E.T.  because of its massive debugging arsenal. Knowing memory map helps a lot.

Memory Map
http://gamesx.com/wiki/doku.php?id=x68000:memory_map (http://gamesx.com/wiki/doku.php?id=x68000:memory_map)

Lydux is like a prophet. The things he says at first might seem not understandable. But the time will come. And when it comes, they are of immense value.

Keep the scene alive !
Eidis

P.S. Who wants to join the Eidis cracking group ?
Title: Re: Major release: Bomber Man. Cracked by Eidis cracking group.
Post by: caius on July 10, 2014, 05:45:27 PM
So, did you disassembled the main executable "BM.X", changed the two values and reassembled it or patched it directly with an HEX editor (I can see the two NOP instructions opening it with an editor)?Did you patch memory locations of FDC or IOSC?
Title: Re: Major release: Bomber Man. Cracked by Eidis cracking group.
Post by: eidis on July 11, 2014, 01:39:00 AM
 Hi Caius !

I ran the game from HDD and waited for the place where it stalled because no floppy disk was inserted. Then I used "Break" and started looking for something out of the ordinary, which was almost everything because of my lack of experience :D There were some interesting jumps to IPL which went in seemingly endless loop so I took care of them in the debugger.

After that I wrote down the unchanged bytes, their nearest bytes and opened BM.X in HxD Hexeditor. The written down values were easily found and replaced with 4E71 and the game worked. Beginners luck, I suppose.

Keep the scene alive !
Eidis