Logika Assembly 32 bit (Bahasa Rakitan)

[mywisdom]

Logika Assembly 32 bit (Bahasa Rakitan)

lagi bikin b0tn3t buat prolonged/permanent dns attack eh tangan gue gatel mao nyambi
maenan dulu ah biar gak puyeng (deface and ddos is common attacks, we
don't play it anymore, we'are goin to play with prolonged / possible permanent dns attack soon)

logika and

Code:

;contoh rutin utama:
mov eax,23h
mov ebx,23h
and eax,ebx

logika ini mengharuskan kondisi keduanya terpenuhi jika ya maka true(1)
jika tidak maka false (0).
contoh kode asm 32 bit dengan logika and:

Code:

global _start
_start:
mov eax,23h
mov ebx,23h
and eax,ebx

assemble dan linker:

Code:

root@mywisdom-Vostro1310:/home/mywisdom/asm# nasm -f elf and.asm -g
root@mywisdom-Vostro1310:/home/mywisdom/asm# ld -o and and.o

Ok sekarang kita analisis hasil statemen di atas dg gdb:

Code:

root@mywisdom-Vostro1310:/home/mywisdom/asm# gdb -q and
Reading symbols from /home/mywisdom/asm/and...done.
(gdb) run
Starting program: /home/mywisdom/asm/and

Program received signal SIGSEGV, Segmentation fault.
0x0804806c in ?? ()
(gdb) i r
eax            0x23    35
ecx            0x0    0
edx            0x0    0
ebx            0x23    35
esp            0xbffff480    0xbffff480
ebp            0x0    0x0
esi            0x0    0
edi            0x0    0
eip            0x804806c    0x804806c
eflags         0x210202    [ IF RF ID ]
cs             0x73    115
ss             0x7b    123
ds             0x7b    123
es             0x7b    123
fs             0x0    0
gs             0x0    0
(gdb)

terlihat hasil logika and pada register eax:
eax ----- 0x23 / 23h

berikut ini cara kerja logika and tadi:
mov eax,23 --- register eax diisi 23
mov ebx,23 --- register ebx diisi 23

23 dikonvert ke biner adalah: 00100011

berikut ini logika and :

Code:

------------
0 and 0 -> 0
1 and 0 -> 0
1 and 1 -> 1
-------------

jadi:

Code:

00100011
00100011
_____________ (and)
00100011  = 23h

Logika or
rutin utama:

Code:

;contoh rutin utama:
mov eax,50h
mov ebx,20h
or eax,ebx

logika ini gak musti kondisi keduanya terpenuhi dia udah bisa true (1)

contoh kode asm 32 bit dengan logika or:

Code:

global _start
_start:
mov eax,50h
mov ebx,20h
or eax,ebx

assemble dan linker:

Code:

root@mywisdom-Vostro1310:/home/mywisdom/asm# nasm -f elf or.asm
root@mywisdom-Vostro1310:/home/mywisdom/asm# ld -o or or.o

analisis hasil dengan gdb:

Code:

root@mywisdom-Vostro1310:/home/mywisdom/asm# gdb -q or
Reading symbols from /home/mywisdom/asm/or...(no debugging symbols found)...done.
(gdb) r
Starting program: /home/mywisdom/asm/or

Program received signal SIGSEGV, Segmentation fault.
0x0804806c in ?? ()
(gdb) i r
eax            0x70    112
ecx            0x0    0
edx            0x0    0
ebx            0x20    32
esp            0xbffff480    0xbffff480
ebp            0x0    0x0
esi            0x0    0
edi            0x0    0
eip            0x804806c    0x804806c
eflags         0x210202    [ IF RF ID ]
cs             0x73    115
ss             0x7b    123
ds             0x7b    123
es             0x7b    123
fs             0x0    0
gs             0x0    0
(gdb)

eax menjadi berisi 0x70 yg merupakan hasil or dg ebx

perhatikan rutin simple ini:
mov eax,50h ----> register eax diisi 50 hex
mov ebx,20h ----> register ebx diisi 20 hex
or eax,ebx ----> lakukan logika or untuk reg eax dan ebx

itunganya gini:

0x50 = 01010000 -> dalam bilangan biner
0x20 = 00100000

logika dimulai:

Code:

01010000
00100000
_________(or)
01110000          ----------->>>> 0x70

keterangan logikanya:

0 or 0 = 0
1 or 0 = 1
1 or 1`= 1

Logika XOR (Exclusive Or)
xor ==exclusive or , ini semua logika sama dengan or tapi bedanya klo 2
kondisi true dia malah jadi false. check tis out:


contoh potongan xor:

Code:

global _start
_start:
mov eax,1h
mov ebx,2 h
xor eax,ebx

oke simpan dg nama xor.asm lalu assemble dan linker

Code:

nasm -f elf xor.asm -g
ld -o xor xor.o

gdb:

Code:

root@mywisdom-Vostro1310:/home/mywisdom/asm# gdb -q xor
Reading symbols from /home/mywisdom/asm/xor...(no debugging symbols found)...done.
(gdb) r
Starting program: /home/mywisdom/asm/xor

Program received signal SIGSEGV, Segmentation fault.
0x0804806c in ?? ()
(gdb) i r
eax            0x3    3
ecx            0x0    0
edx            0x0    0
ebx            0x2    2
esp            0xbffff480    0xbffff480
ebp            0x0    0x0
esi            0x0    0
edi            0x0    0
eip            0x804806c    0x804806c
eflags         0x210206    [ PF IF RF ID ]
cs             0x73    115
ss             0x7b    123
ds             0x7b    123
es             0x7b    123
fs             0x0    0
gs             0x0    0
(gdb)

hasil xor terlihat pada register eax yg menjadi 0x3 / 3 hexa .

Code:

1  = 00000001
2  = 00000010
       ---------(xor)  
        00000011 == 0x3

nih klo buat yg xor:

Code:

1 xor 1 equ 0
1 xor 0 equ 1
0 xor 0 equ 0

.

[ndutz.newbie]

kayak pake cheat engine ya om dom???

[mywisdom]

(08-06-2010 12:54 AM)ndutz.newbie Wrote:  kayak pake cheat engine ya om dom???

xxixi bukan bro beda ni koding asmnya, cheat engine kita edit alamat2 memori yg bergerak

[ndutz.newbie]

(08-06-2010 12:56 AM)mywisdom Wrote:  

(08-06-2010 12:54 AM)ndutz.newbie Wrote:  kayak pake cheat engine ya om dom???

xxixi bukan bro beda ni koding asmnya, cheat engine kita edit alamat2 memori yg bergerak

wah begitu ya..oke om dom saatnya ane mencoba thanx ya atas tuts nya

[mywisdom]

sama 2 bro moga 2 bermanfaat bro, btw yg posting di forum asm ma c sepi euy

[ian182]

sip deh om dom .tambahin lagi dong tutorialnya .belajar lagi ah

[zer03s]

blajar,blajar,blajar

[putri sitasari]

huff, akhirna qu slesai jg bacana, hihii ma'acih iyahhh

[android2009]

om dom aku mau tanya nih
processorku kan AMD
kira-kira beda gak kodingnya?

[mywisdom]

xor:
sama aja logikanya bro

sh-3.2# cat xor.asm
bits 64
global _start
_start:
mov rax,1
mov rbx,2
xor rax,rbx
sh-3.2#
sh-3.2# gdb -q xor2
Reading symbols from /var/adm/xor2...(no debugging symbols found)...done.
(gdb) run
Starting program: /var/adm/xor2

Program received signal SIGSEGV, Segmentation fault.
0x000000000040008c in ?? ()
(gdb) i r
rax 0x3 3


and

sh-3.2# gdb -q and
Reading symbols from /var/adm/and...(no debugging symbols found)...done.
(gdb) run
Starting program: /var/adm/and

Program received signal SIGSEGV, Segmentation fault.
0x0000000000400091 in ?? ()
(gdb) i r
rax 0x17 23

sh-3.2# cat and.asm
bits 64
global _start
_start:
mov rax,23
mov rbx,23
and rax,rbx
sh-3.2#