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I
used original disk IPF
#199 (2 disks)
- X-Copy, Action Replay and DevPac (or AsmOne)
- resourcer/debugger (AR, Mega-Mon...)
- Sector
Trasher/Silents or Sectorizator
/ Exe2Boot
(see ToolDisks)
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Try
the IPF disks. Non-Dos game, No passwords required.
First of all, make a copy of the first disk and
boot it. The copy stop at the start and stay on
a black screen. |
A
quick scan of the disk with X-Copy show you an error
on track 1. Seems to be a disk based protection.
Take a look at the bootblock (sector 0 track 0) :
Bingo, it's a CopyLock ^^
The CopyLock is an encrypted trace-mode code. The files
(datas and programs) are encrypted with the Copylock
Keydisk computed by the copylock code.
More information and tools about CopyLock here.
Now, there are several ways to find and crack a copylock,
depending of the difficulty of the copylock (number
of keys, levels of encryption, PDOS format...). Here
is a very simple one.
By disassembling the boot :
I loaded and disassembled the starter program (11 sectors
from block 24):
I found the copylock routine by searching pea and/or
illegal instructions. or follow the program.
moveq
#0,d0
mobeq #1,d1
lea $110.w,a3
pea getvalue(pc) ; copylock : patch here
move.l (sp)+,$10
illegal
getvalue: ... |
the
keydisk is saved at $110.
just after copylock, the starter load main program at
$804 and decode it with the key before start it :
move.l
$110.w,d0 ; the copylock key
lea $804.w,a0
move.w #$e80,d7
.decrypt:
move.l (a0),d1
eor.l d0,d1
move.l d1,(a0)+
rol.l #1,d0
dbf d7,.decrypt
jmp
$804.w ; start main |
To
find the key value in this case, you don't need to remove
TMV and decode the copylock routine.
Reboot, and with AR, stop when the Ruff picture appear.
Take a look at the address $110 in memory : m 110
here
is the copylock code : $BED7B57D
now
we have to patch the copylock code with the good key
directly in the starter program or from the boot after
loading and before start it.
patch
after lea $110.w,a3 :
move.l
#$BED7B57D,d0
move.l d0,(a3) ; put good key at 110
rts ; no more copylock test |
You
can directly modify the code under AR and rewrite
the prog on the copy disk :
rt 2 1 70000 ; read the prog in memory
f 48 7a ; search for pea ### (copylock)
a 70b7c ; type the new code here
wt 2 1 70000 ; write the new cracked program
Watch the video of this method here on Youtube
or crack it from the bootblock with the patch :
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loader:
; see below
...
lea patch(pc),a0
lea $77c(a3),a1 ; here is the copylock routine
to patch
moveq #size-1,d7
.copy:
move.b (a0)+,(a1)+
dbf d7,.copy
; original code
movea.l 8.l,a5
jmp (a3) ; start
patch:
move.l #$BED7B57D,d0
move.l d0,(a3) ; put good key at 110
rts
size=*-patch
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we
have just enough place in the boot to put a trainer
(and even a little "textro" or other tiny
code).
Reboot,
test, and enjoy. Seems to work
Test the second disk to verify if another copylock exist.
If you have doubt about another copylock in main "crypted"
program, put a breakpoint with AR at $804 to take a
look at the decrypted code. Seems to be nothing more
for this game.
we can see that the prog load a "directory"
file with the informations of all the files of the game
(sector position, len, num disk...) : great ;)
tested
with the trainer by Gradius/Anthrox
The game work perfectly :
2008
(c) Heavy/VrS!/Cyb
Download
:
- Cracked
disk 1 + trainer (right mouse button at boot)
- sources of the
original boot, patched boot and trainer in boot
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..=
Cracking Tuto : simple copylock =.. 
