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immediate operand not allowed?

Started by hesho28, October 05, 2013, 09:41:58 AM

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hesho28

Hello,

i have an address 00400030 which have an array of bytes. I want to copy that array of bytes to another address (4 Bytes).

Without using ReadProcessMemory , i used:

LOCAL ex:DWORD

mov [00400030h],eax
mov ex,[eax]


But i always get this error:
HelloWorldx.asm(73) : error A2001: immediate operand not allowed
HelloWorldx.asm(74) : error A2070: invalid instruction operands

I use RadAsm Editor.

Thanks in advance.

dedndave

why are you trying to write to a fixed address ?
if it's in one of the program sections, put a label on it

KeepingRealBusy

The (74) error can be corrected by:


mov DWORD PTR ex,eax


Dave.

hutch--

What you are after is easy enough to do, I would be interested in why you want to read data from 30h after the DOS header.


IF 0  ; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤
                      Build this template with "CONSOLE ASSEMBLE AND LINK"
ENDIF ; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    include \masm32\include\masm32rt.inc

    .code

start:
   
; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    call main
    inkey
    exit

; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

main proc

    LOCAL var:DWORD

    mov eax, 00400030h      ; load the address into EAX
    mov eax, [eax]          ; dereference it to get the data at that address
    mov var, eax            ; copy 4 bytes into local variable

    print hex$(var),13,10   ; display it at the console

    ret

main endp

; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

end start

qWord

Quote from: hesho28 on October 05, 2013, 09:41:58 AMHelloWorldx.asm(73) : error A2001: immediate operand not allowed
Addressing through immediate  values requires to specify the segment:
mov DS:[00400030h],eax
MREAL macros - when you need floating point arithmetic while assembling!

hutch--

Like this ?


    mov eax, DS:00400030h
    mov var, eax            ; copy 4 bytes into local variable

jj2007

It's all the same:
   nop
   mov ds:[403000h], eax
   mov ds:403000h, eax
   mov eax, ds:00400030h
   mov eax, ds:[00400030h]
   nop
   mov eax, 00400030h  ; no ds:
   nop

00401009       ³.  90                  nop
0040100A       ³.  A3 00304000         mov [403000], eax
0040100F       ³.  A3 00304000         mov [403000], eax
00401014       ³.  A1 30004000         mov eax, [400030]
00401019       ³.  A1 30004000         mov eax, [400030]
0040101E       ³.  90                  nop
0040101F       ³.  B8 30004000         mov eax, offset 00400030
00401024       ³.  90                  nop


Poor hesho28 has officially 5 posts, but four of them have been mercilessly deleted :eusa_naughty:

hutch--

 :biggrin:

The real problem is he will not tell us what he is doing wanting to read from the DOS/PE header. Since I will willingly turn in anyone who thinks I will cover them for illegal postings to the NSA, Mossad, KGB or whoever wants the data, perhaps our friend could come clean as to what he is doing, otherwise he may hit 5 out of 5 and the chance to find a venue better suited to his requirement.

dedndave

i was told not to help someone until they explain themselves
i guess that doesn't apply to everyone   :redface:

the first thing i noticed was that he had made 4 previous posts, all of which went to the garbage bin