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How to pass a value from LUA script to CE script

 
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Pirulito
Newbie cheater
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Joined: 13 May 2017
Posts: 13
PostPosted: Sun Mar 04, 2018 8:07 pm    Post subject: How to pass a value from LUA script to CE script Reply with quote
Please, why is this CE script not working?

Code:

define(address,"GameProcess.exe"+54762B)
define(bytes,8D 4D 08 C6 45 FC 02)

[ENABLE]

assert(address,bytes)
alloc(newmem,$10)
alloc(result,$4)
registersymbol(result)

label(code)
label(return)

{$lua}
if syntaxcheck then return end
   autoAssemble(string.format("result:\ndb CA CA CA CA"))
{$asm}

newmem:

code:
  lea ecx,[ebp+08]
  mov byte ptr [ebp-04],02
  jmp return

address:
  jmp newmem
  nop
  nop
return:

[DISABLE]

address:
  db bytes
  // lea ecx,[ebp+08]
  // mov byte ptr [ebp-04],02

unregistersymbol(result)
dealloc(result)
dealloc(newmem)


All I want (this is a test, for me to learn how to pass a value from the LUA script to the CE script) is that the LUA script write the following in the CE script:

Code:

result:
  db CA CA CA CA


but it does not work. When I go to the injected code in the game, I do not see the bytes CA CA CA CA in the address defined by "result". I see the address "result" but not the bytes that I expected to be there.

How to fix it?
Thank you.
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FreeER
Grandmaster Cheater Supreme
Reputation: 53

Joined: 09 Aug 2013
Posts: 1091
PostPosted: Sun Mar 04, 2018 8:56 pm    Post subject: Reply with quote
lua code like that is run before the script is actually enabled, so "result" doesn't exist.
For something like this you can just use "return ..." instead of "AutoAssemble(...)", which will cause the returned string to be inserted as assembly code in place of the lua block, eg.

Code:
<?xml version="1.0" encoding="utf-8"?>
<CheatTable>
  <CheatEntries>
    <CheatEntry>
      <ID>0</ID>
      <Description>"Auto Assemble script"</Description>
      <LastState Activated="1"/>
      <VariableType>Auto Assembler Script</VariableType>
      <AssemblerScript>[enable]
alloc(result,4)
registersymbol(result)

{$lua}-- doesn't do anything we don't want to happen during a syntax check so let it run
return string.format("result:\ndb CA CA CA CA")
{$asm}
[disable]
unregistersymbol(result)
dealloc(result)
</AssemblerScript>
      <CheatEntries>
        <CheatEntry>
          <ID>1</ID>
          <Description>"No description"</Description>
          <LastState Value="CA CA CA CA" RealAddress="051B0000"/>
          <ShowAsHex>1</ShowAsHex>
          <VariableType>Array of byte</VariableType>
          <ByteLength>4</ByteLength>
          <Address>result</Address>
        </CheatEntry>
      </CheatEntries>
    </CheatEntry>
  </CheatEntries>
</CheatTable>


I've used that a few times when I needed a lot of nops or 0 bytes etc. and didn't want to type/copy+paste them out.

Alternatively (if you really wanted to implement it as AutoAssemble) you'd need a separate script with the lua code in it that's run after the first which creates and registers result, or to use a lua timer as a delay to essentially automate the above, or look into the lua template which actually allows lua code to be called from inside the script (probably slow though, haven't really every tried to use it, however the other methods run it just once when the script is enabled, though the timer could be setup to keep looping and run after it detects a change in memory it's not exactly the same).

Oh, I think you can also do this:
Code:
<?xml version="1.0" encoding="utf-8"?>
<CheatTable>
  <CheatEntries>
    <CheatEntry>
      <ID>2</ID>
      <Description>"Auto Assemble script"</Description>
      <LastState Activated="1"/>
      <VariableType>Auto Assembler Script</VariableType>
      <AssemblerScript>[enable]
alloc(result,4)
registersymbol(result)

{$lua}
value = 0xCACACACA
{$asm}
result:
 dd $value
[disable]
unregistersymbol(result)
dealloc(result)
</AssemblerScript>
      <CheatEntries>
        <CheatEntry>
          <ID>3</ID>
          <Description>"No description"</Description>
          <LastState Value="CA CA CA CA" RealAddress="051A0000"/>
          <ShowAsHex>1</ShowAsHex>
          <VariableType>Array of byte</VariableType>
          <ByteLength>4</ByteLength>
          <Address>result</Address>
        </CheatEntry>
      </CheatEntries>
    </CheatEntry>
  </CheatEntries>
</CheatTable>


might only be implemented for 4 byte values though...
_________________
https://github.com/FreeER/ has a few CE related repos
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Pirulito
Newbie cheater
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Joined: 13 May 2017
Posts: 13
PostPosted: Tue Mar 06, 2018 5:05 pm    Post subject: Reply with quote
Thank you, FreeER. Your suggestion to use return solved my problem. I had many lines to write to the script so I concatenated the lines and used return on the final big string and it worked perfectly. Smile
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