Lineage 2 dat files decoder. Author: Hint aka Ilya

l2datdec.php

<?php

/** 
 * L2 file decoder (4 october 2011). 
 * @author Hint aka Ilya 
 */

function decode($filename, $original = true) 
{ 
  $file = @file_get_contents($filename); 
  if (!$file) return false; 
  if (strlen($file) < 28 + 128) return false; 
  $head = mb_convert_encoding(substr($file, 0, 28), 'UTF-8', 'UTF-16LE'); 
  if ($head != 'Lineage2Ver413') return false; 
   
  $blocks = intval((strlen($file) - 28) / 128); 
  if ($blocks < 1) return false; 
   
  $size = $blocks * 128; 

  $file = substr($file, 28, $size); 
   
  if ($original) 
  { 
    $s = base64_decode('l985hHLd9zfvCgzRfo0XLw/vFmGjiorh1ugpvBxuTDz8GSkt2p75AXXkbnOUoYhQtkF9A75u6idNPtHd5bXXvecswKC3HQNghlVjOIF5OgLJpn2e8rRet8CNS+MpCDzkUOaPeGe2dJMU1AUR0JvFdEVRuqhqidw4Ej3BZo/XLYM='); 
    $key = gmp_init('0x' . bin2hex($s)); 
    $exp = gmp_init('0x35'); 
  } 
  else 
  { 
    $s = base64_decode('dbTW3lwBZUQGihrPElhp9D0uCfxVuLHiiVVtr5uHV2NVk0RiiLNlPaHOkch7saXBjxYyNJXFXX1ywIkKg/ab/R/ZQ06xwC8+Rnnt+kMwkxkHASnCZ8hWBNh7tluuIF3jcHrx0hCIgau1Z8Oz0GmuZ8OkxqOqk9JkE9TGYJSuIDk='); 
    $key = gmp_init('0x' . bin2hex($s)); 
    $exp = gmp_init('0x1d'); 
  } 
   
  $data = ''; 
  for ($i = 0; $i < $blocks; ++$i) 
  { 
    $block = substr($file, $i * 128, 128); 
    $res = gmp_powm('0x' . bin2hex($block), $exp, $key); 
    if (!is_resource($res)) return false; 
    $hex = gmp_strval($res, 16); 
    if (strlen($hex) != 250) return false; 
    $s = pack('H*' , $hex); 
     
    $size = ord($s[0]); 
    if ($size > strlen($s) - 1) return false; 
     
    if ($size != 0x7c) 
    { 
      $p = strlen($s) - $size; 
      while ($p > 2 && $s[$p - 1] != "\0") --$p; 
      $s = substr($s, $p, $size); 
    } 
    else 
    { 
      $s = substr($s, -$size); 
    }     
    $data .= $s; 
  } 

  $a = unpack('L', $data); 
  if (!is_array($a) || !isset($a[1])) return false; 
   
  $size = intval($a[1]); 
  $data = substr($data, 4); 
  $result = gzuncompress($data); 
  if (strlen($result) != $size) return false; 
   
  return $result; 
}

// $s = decode('/Users/Stmol/Downloads/armorgrp.dat', true); 
// if ($s === false) die('Error!');
// file_put_contents('dec-l2.ini', $s);