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Old 01-25-2010, 02:40 AM
kingbowser kingbowser is offline
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Join Date: Jan 2010
Posts: 1
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Hi, I'm an Italian user. I came here redirected by rongchaua. I have a program (mind workstation) of which I would like to find the serial number for my computer, but I'm a n00b in this sector.
From which I could understand the executable is obfuscated with Xenocode, while some DLLs are packed with Armadillo.

With PEtools I dumped the files while running, so I got an EXE in which strings and procedures are encrypted (Xenocode). I couldn't manage to deobfuscate it with the rongchaua and libx tools. Can you help me?

As I mostly design harware (electronic engineer) I'm not so trained in programming/hacking/cracking

Thank you for your time and support
[and sorry for my Engrish lol]

I know I shouldn't make double posts ...

[Then why do it ?!?!?!. Just use the Edit button]

...but I extracted with LordPE and Reflector something useful: Xenocode postbuild (2008 or 2009 I don't know) string decryption algorithm

Here it is (in C#)

Code:
public static string decrypt(string enc_string, int key)
{
    char[] chArray;
    ushort num3;
    bool flag;
    ushort num = (ushort) key;
    if ((((uint) flag) - num3) >= 0)
    {
        flag = ((uint) key) > uint.MaxValue;
        if (flag)
        {
            goto Label_00EA;
        }
        chArray = new char[enc_string.Length / 4];
    }
    else if ((num | 1) != 0)
    {
        goto Label_0091;
    }
    int index = 0;
    goto Label_00F4;

Label_007A:
    if (!flag)
    {
        index++;
        goto Label_00F4;
    }

Label_0083:
    do
    {
        num3 = (ushort) (num3 - num);
        chArray[index] = (char) num3;
        num = (ushort) (num + 0x6fd);
    }
    while ((((uint) flag) + ((uint) key)) < 0);
    goto Label_012A;

Label_0091:
    num3 = (ushort) ((((enc_string[4 * index] - 'a') + ((enc_string[(4 * index) + 1] - 0x61) << 4)) + ((enc_string[(4 * index) + 2] - 0x61) << 8)) + ((enc_string[(4 * index) + 3] - 0x61) << 12));
    if (((uint) index) > uint.MaxValue)
    {
        goto Label_012A;
    }
    if ((num + num) <= uint.MaxValue)
    {
        goto Label_0083;
    }
    goto Label_007A;

Label_00EA:
    return new string(chArray);

Label_00F4:
    if (index < (enc_string.Length / 4))
    {
        goto Label_0091;
    }
    goto Label_00EA;

Label_012A:
    flag = (((uint) key) + ((uint) key)) > uint.MaxValue;
    goto Label_007A;
}
Now I'm going to clean it from garbage code and rewrite it in a little "string decrypter" program. Bye

Last edited by Git : 01-25-2010 at 08:07 AM.
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