Is it possible to write compare script with lua ?

[Blackrosemmt]

Hi guys

Is it possible to write compare script with lua ?
I need to add 2 offsets then comparing them to value 0 as the below example.

Code: Select all

newmem:
push edx
mov edx,[esi+ec]     //first offset ec
cmp [edx+11c],0	  //second offset 11c
pop edx

jne originalcode

//mov [esi+28],eax
jg game.exe+1861D6
jmp exit

originalcode:

mov [esi+28],eax
jg game.exe+1861D6

[GreenHouse]

Hi guys

Is it possible to write compare script with lua ?
I need to add 2 offsets then comparing them to value 0 as the below example.

Well, yes it is possible to write a compare, but it depends on what you're trying to do. That question is way too broad.
But a compare like that one from ASM to LUA, would be something like this, in a simple way:

Code: Select all

if readInteger(readInteger(Address1)+0x11C) == 0x0
   then print('Something is done here) 
else
   print ('Something else is done here') 
end

But if you're planning to run LUA mid ASM, you can't. LUA will always run first.

[LeFiXER]

...
But if you're planning to run LUA mid ASM, you can't. LUA will always run first.

With the latest version of CE you can now run in-line Lua code via {$LUACODE}.

Code: Select all

newmem:
push edx
mov edx,[esi+ec]	//first offset ec
cmp [edx+11c],0		//second offset 11c
{$luacode r1=esi r2=edx}
printf("esi = %X\nedx = %X\nesi+ec = %X\nedx+11c = %X", r1,r2,r1+0xEC,r2+0x11C)
{$asm}
pop edx

jne originalcode

//mov [esi+28],eax
jg game.exe+1861D6
jmp exit

originalcode:

Not exactly what you need but will give you an idea of how in-line Lua can be used which happens to print the values held in the registers defined at the point of execution, along with some offsets added.

[GreenHouse]

With the latest version of CE you can now run in-line Lua code via {$LUACODE}.

That's nice, I didn't know about that. I'll check that out later to see what can be done with it.

[LeFiXER]

Sadly, it's not really documented but yeah it's neat for sure.

[Blackrosemmt]

With the latest version of CE you can now run in-line Lua code via {$LUACODE}.

Thanks @LeFiXER for the reply. I wanted to write all script in Lua because the games sometimes crash using push pop in ASM becasue of invalid pointers, so I need to give it a try in Lua to see if game will still crash or not.
can you please help me writing it in Lua according to these information :

"game.exe"+18610E //Base address
EC // first offset
11C // second offset
then compare 11C to 0

jne originalcode // jump if not equal to originalcode
mov eax,[esi+28] // if equal then make this injection


I saw in another posts that they are writing pointer and offset scripts something like
[[[game.exe+offset0]+offset1]+offset2]
but I didnt find for compare in Lua.

[LeFiXER]

I saw in another posts that they are writing pointer and offset scripts something like
[[[game.exe+offset0]+offset1]+offset2]
but I didnt find for compare in Lua.

You're welcome, although it's not difficult to use a reputable search engine to answer your query. Nevertheless,

Code: Select all

local base = getAddressSafe('game.exe+18610E')
local pointer = getAddressSafe('[[[' .. base .. ']+EC]+11C')

if readInteger(pointer) == 0 then
  -- The value held in pointer = 0

The function readInteger may differ based on the value type you're reading.