help me to remove dll protection

burndeep · 2013-09-15T12:19:02.000Z

hi everyone , please help me to remove the protection login a dll. i've a dll but it just can work in one id (protected) and i want use it with another id . any suggestion?

Is there an error message?

At some point in the dll code it comes down to a compare instruction, and a jump. If you reverse the jump instruction (that is, replace it with it's opposite: jump-greater-equal's opposite would be jump-less-than for example, jne's opposite would be je) it will allow the dll only when the ID is invalid : D

Trouble is actually finding the location of that one instruction. I'm not good at it. Chances are it's 5-20 lines above where the error message is shown. worse case it's a few functions calls before. Find it then use a hex editor to change the instruction.

Is one way, I think.

-------------------

Code:

''Pseudo-syntax, not exact instructions..

If  IsHardwareIdValid() == True Then
''Let the code run
''here
Else
ErrorMessage()
End If

in asm:

mov eax, IsHardwareIdValid()
cmp eax, 0
jg validID
''else, falls through to error message
ErrorMessage()
exit()
:validID
...good code..


^^change jg to jle (or jz maybe?). Then it will jump to the "good code" when the ID is invalid : D
-reversing the logic of the original if statement/control structure.

help me to remove dll protection

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