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Oloron
December 21st, 2003, 07:45
hey VB reversers i know u are out there
just a little keygen-me here i wrote to test a person's abilities in reversing VB and dealing with obfuscation. its not overly difficult but it should be half challenging imho
sonkite
February 13th, 2004, 16:37
Quote:
[Originally Posted by Oloron]hey VB reversers i know u are out there
just a little keygen-me here i wrote to test a person's abilities in reversing VB and dealing with obfuscation. its not overly difficult but it should be half challenging imho


pcode sux, but here is a valid serial

name: sonkite
code: 756B6863617766222820
evlncrn8
February 13th, 2004, 19:20
Quote:
[Originally Posted by sonkite]pcode sux, but here is a valid serial

name: sonkite
code: 756B6863617766222820


heh neat.. hi sonkite
ZaiRoN
February 13th, 2004, 19:55
Hi sonkite,
Quote:
pcode sux
pcode... this is not pcode
Btw, your combination is not correct, and it's valid for your computer only. iirc, the name/serial protection routine is based over some specific values taken from the machine. Have you sniffed the right serial for your name?

ZaiRoN
sonkite
February 14th, 2004, 10:24
Yeah it was not pcode, here is what i got so far:

take lpTotalNumberOfBytes from C:\ (static?) using GetDiskFreeSpaceExA
in my case 81929000h (2173865984.0) put into fpu and add it with 4294967296.0 (static?) == 6468833280.0

then

20h ' ' xor 6 == 26h
73h 's' xor 6 == 75h

20h ' ' xor 4 == 24h
6Fh 'o' xor 4 == 6Bh

20h ' ' xor 6 == 26h
6Fh 'n' xor 6 == 68h

20h ' ' xor 8 == 28h
6Bh 'k' xor 8 == 63h

20h ' ' xor 8 == 28h
69h 'i' xor 8 == 61h

20h ' ' xor 3 == 23h
74h 't' xor 3 == 77h

20h ' ' xor 3 == 23h
65 'e' xor 3 == 66h

20h ' ' xor 2 == 22h
20h ' ' xor 8 == 28h
20h ' ' xor 0 == 20h

which equals = 75 6B 68 63 61 77 66 & 26 24 26 28 28 23 23 22 28 20

compare entered serial against 756B6863617766 222820
Foreigner
February 14th, 2004, 19:43
Hi people,
I am new to Visual Basic, can you help me?
I am not able to find all the informations sonkite gave us; in particular, how did you find the value 4294967296 and where did you find the call to GetDiskFreeSpaceExa? I am using Ollydbg without success... any hint!?!

f.
sonkite
February 15th, 2004, 07:10
Quote:
[Originally Posted by Foreigner]Hi people,
I am new to Visual Basic, can you help me?
I am not able to find all the informations sonkite gave us; in particular, how did you find the value 4294967296 and where did you find the call to GetDiskFreeSpaceExa? I am using Ollydbg without success... any hint!?!

f.


If you follow this call (at startup of crackme):

0043C539 CALL DWORD PTR [EDX+38]
.....
73577C78 CALL DWORD PTR [7358977C] ; GetDiskFreeSpaceExA
.....
735743A1 FILD QWORD PTR [ESP+4]
735743A5 POP ESI
735743A6 FSTP QWORD PTR [ESP]
735743A9 FLD QWORD PTR [ESP]
735743AC FMUL QWORD PTR [73587830]
735743B2 MOV DWORD PTR [ESP],EAX
735743B5 MOV DWORD PTR [ESP+4],EDX
735743B9 FILD QWORD PTR [ESP]
735743BC XOR EAX,EAX
735743BE FSTP QWORD PTR [ESP]
735743C1 FADD QWORD PTR [ESP]
735743C4 FSTP QWORD PTR [ECX+8]

There it calculates the values.