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Reading a Pointer Value? [C++]
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lurc
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PostPosted: Thu Feb 28, 2008 6:37 pm    Post subject: Reading a Pointer Value? [C++] Reply with quote
I want to be able to read a pointer value.
So in asm it would be like

DWORD dReturn;
_asm {
mov esi,[PointerAddy]
mov esi,[esi]
mov edx,[PointerOffset]
mov ebx,[esi+edx]
mov [dReturn],ebx
}

but im sure thats wrong, cuz the game crash's...

i also wanna try using ReadProcessMemory for it

ReadProcessMemory( hMaple, (LPVOID)&PointerAddy, (LPVOID)&dReturn, sizeof(PointerAddy), NULL );
DWORD AddOffset = dReturn + PointerOffset;
ReadProcessMemory( hMaple, (LPVOID)&AddOffset, (LPVOID)&Value, sizeof(AddOffset), NULL );

but this definintly doesnt give me the value.. or maybe i just got the wrong pointers Razz

help is appreciated.
-Lurc
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atom0s
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PostPosted: Thu Feb 28, 2008 6:49 pm    Post subject: Reply with quote
From what I can see, you are using the addresses incorrectly, you are trying to pass the address of the storage variable and not its value. Instead, write:

Code:
ReadProcessMemory( hMaple, (BYTE*)PointerAddy, &dReturn, sizeof(DWORD), NULL );
DWORD AddOffset = dReturn + PointerOffset;
ReadProcessMemory( hMaple, (BYTE*)AddOffset, &Value, sizeof(AddOffset), NULL );


I also suggest not dumping the end result into something you are using already. Instead make a new variable to hold that value.
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Flyte
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PostPosted: Thu Feb 28, 2008 6:51 pm    Post subject: Re: Reading a Pointer Value? [C++] Reply with quote
Code:
#define ReadPtrVal(x,y,z) *((z *) (x + y))

int val = ReadPtrVal(pointer, offset, int);


Or do you mean multi-level pointers?

Note: Injected dll.
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atom0s
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PostPosted: Thu Feb 28, 2008 6:54 pm    Post subject: Re: Reading a Pointer Value? [C++] Reply with quote
Flyte wrote:
Code:
#define ReadPtrVal(x,y,z) *((z *) (x + y))

int val = ReadPtrVal(pointer, offset, int);


Or do you mean multi-level pointers?

Note: Injected dll.


Based on what he asked, (using RPM) I figured it was from a stand alone trainer type thing.
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lurc
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PostPosted: Thu Feb 28, 2008 6:57 pm    Post subject: Reply with quote
Here's my code.
Trying to read the Channel Pointer

Code:
void ReadChannel()
{
   DWORD Address, Read, Value;
   TCHAR Writeto[MAX_PATH];
   HANDLE hMaple = GetCurrentProcess();

   if ( !hMaple ) { MessageBox( hWnd, L"Unable to get handle", szError, MB_OK | MB_ICONERROR ); return; }

   ReadProcessMemory( hMaple, (BYTE*)0x00850468, &Address, sizeof(DWORD), NULL );
   Read = Address + 0x20C4;
   ReadProcessMemory( hMaple, (BYTE*)Read, &Value, sizeof(Read), NULL );

   _itot_s( Value, Writeto, 15, 10 );
   SetDlgItemText( hWnd, ID_STATIC1, Writeto );
}


I get a value of 13009xxxx <-- something like that.
So im guessing my pointers wrong, or im going about doing this wrong...


Edit: wo, missed 2 posts... lmao
its an injected dll Razz
thats why i tried inline asm first... but since using RPM works fine in ms i just decided to try it too
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Flyte
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PostPosted: Thu Feb 28, 2008 7:04 pm    Post subject: Reply with quote
Ok, ReadProcessMemory isn't needed in an injected dll, you can do manual reads.

(I can notice it is injected because of: HANDLE hMaple = GetCurrentProcess(); )
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lurc
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PostPosted: Thu Feb 28, 2008 7:09 pm    Post subject: Reply with quote
Alright i tried your method

Code:
void ReadChannel()
{
   DWORD Value = ReadPtrVal( 0x00850468, 0x20C4, DWORD );
   
   TCHAR Writeto[MAX_PATH];

   _itot_s( Value, Writeto, 15, 10 );
   SetDlgItemText( hWnd, ID_STATIC1, Writeto );
}


i got a number like 9779784

so its my pointer.... thats definintly wrong... anyone got the correct channel pointer?

the one i got: Pointer: 0x00850468, Offset: 0x20C4

using these

Channel Pointer - A1 ? ? ? ? 8B 80 ? ? ? ? 89 85 ? ? ? ? 33 C0
Channel Offset - 8B 80 ? ? ? ? 89 85 ? ? ? ? 33 C0 89 45 ?
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Flyte
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PostPosted: Thu Feb 28, 2008 7:14 pm    Post subject: Reply with quote
Is this a multi-level pointer? I don't play maple, so I don't know much about this "channel pointer".
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lurc
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PostPosted: Thu Feb 28, 2008 7:17 pm    Post subject: Reply with quote
lmao, i dont play it either, but i dont think its a mutlilevel pointer.

heres a pic of the pointer and offset?

memview.png
 Description:
 Filesize:  55.02 KB
 Viewed:  7542 Time(s)

memview.png

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Last edited by lurc on Fri Feb 29, 2008 9:36 am; edited 1 time in total
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Flyte
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PostPosted: Thu Feb 28, 2008 7:24 pm    Post subject: Reply with quote
Code:
value  = *((int *) (*((unsigned long *) 0x00850468) + 0x204C))


That's assuming the channel is actually stored in int form.

Edit: Small error with the offset value.

Last edited by Flyte on Thu Feb 28, 2008 8:18 pm; edited 2 times in total
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lurc
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PostPosted: Thu Feb 28, 2008 7:29 pm    Post subject: Reply with quote
Now im getting randomly generated numbers..
every couple seconds it changes value.
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Flyte
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PostPosted: Thu Feb 28, 2008 8:20 pm    Post subject: Reply with quote
lurc wrote:
Now im getting randomly generated numbers..
every couple seconds it changes value.


I accidentally used a messed up offset value, fixed now.
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lurc
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PostPosted: Thu Feb 28, 2008 8:29 pm    Post subject: Reply with quote
Woot! it works! thanks Flyte Smile
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samuri25404
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PostPosted: Thu Feb 28, 2008 8:40 pm    Post subject: Reply with quote
I'm thinking the asm in the first post was wrong, but then again, your pointer might also be wrong.

Code:

_asm {
mov esi,[PointerAddy]
mov esi,[esi]
mov edx,[PointerOffset]
mov ebx,[esi+edx]
mov [dReturn],ebx
}


Shouldn't it be

Code:

mov esi,[Pointer]
mov edx,[Offset]
lea ebx, [esi+edx]
mov [dReturn],ebx


I might be wrong about this, but I also might not.
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Flyte
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PostPosted: Thu Feb 28, 2008 9:15 pm    Post subject: Reply with quote
samuri25404 wrote:
I'm thinking the asm in the first post was wrong, but then again, your pointer might also be wrong.

Code:

_asm {
mov esi,[PointerAddy]
mov esi,[esi]
mov edx,[PointerOffset]
mov ebx,[esi+edx]
mov [dReturn],ebx
}


Shouldn't it be

Code:

mov esi,[Pointer]
mov edx,[Offset]
lea ebx, [esi+edx]
mov [dReturn],ebx


I might be wrong about this, but I also might not.


He said he got it to work, so the pointer was fine, it was just the way he was implementing it.

Also:
Code:
mov     eax, dword [0x00850468]
mov     ax, word [eax+0x204C]
mov     word [channel], ax

channel dw ?
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