immediate operand not allowed?

[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:

Code Select Expand

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:

Code Select Expand


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.

Code Select Expand


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]

HelloWorldx.asm(73) : error A2001: immediate operand not allowed

Addressing through immediate  values requires to specify the segment:

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mov DS:[00400030h],eax

[hutch--]

Like this ?

Code Select Expand


    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

[hutch--]

 

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