Welcome to this reversers tutorial, As this is my first tutorial and I'am not english at all, you'll see that this essay will be poorly written.
You should have softice already installed on your computer, Window$ 3.11 or worse.
Start Timeslice and you will see a nag screen which asks you to register.
So if the author of this program wants us to register why not.
But We will using hwnd timeslic, with hwnd timeslic we'll see the handle of the edit boxes
So lets set a breakpoint on the first edit box bmsg (handle) wm_gettext
Softice wil break four times
After the fourth time push F11 three times and you will here.
2C48 call USER.GETWINDOWTEXTLENGTH
2C4D mov si, ax
2C4F push word ptr [bp-02]
2C52 push ax
2C53 push word ptr [bp+08]
2C56 push word ptr [bp+06]
2C59 call 0001.1B98
2C5E push dx
2C5F push ax
2C60 lea ax, [si+01]
2C63 push ax
2C64 call USER.GETWINDOWTEXT
2C69 jmp 2C7B ;you're here
Disable the breakpoint bd*
step to the code with F10 till you come
to the next section of code
688B push es
688C push cx
688D push ss
688E push word ptr [bp-0C]
6891 call 0001.1712 ;important call
6896 call 0004.6694 ;important call
689B add sp, 000E ;Stack correction
689E mov es, [bp+08]
68A1 push word ptr es:[si+2A] ;Offset Your
Code (OFC)
68A5 push word ptr es:[si+28] ;Adress Your
Code (AFC)
68A9 push word ptr [bp-1A] ;Offset Correct
Code (OCO)
68AC push word ptr [bp-1C] ; Adress Correct
Code>(ACC)
68AF call USER.LSTRCMP ; *** Compare BOTH
serial no's..
68B4 or ax, ax
68B6 je 68BB
68B8 jmp 696E
*** If you do D OFC:AFC you see the code
your entered in my case 12341234
and if you do a D OCO:ACC you see the
correct code in my case 01805882
Till next time lownoise '98
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