Derminating script with this.

Discussion in 'PHP' started by nugis, Jan 25, 2009.

0
  1. #1
    Since my upload script has no extension check, i came up with an idea.
    Basically to block php file uploading.
    Lines in red were added, but the script always commits suicide saying
    "pede raisk". Even with jpg, png etc. files.

    
<?php
session_start();
include ('dbc.php');
if((!empty($_FILES["uploaded_file"])) && ($_FILES['uploaded_file']['error'] == 0)) {
  $filename = str_replace(array('Ö', 'Ä', 'Ü', 'Õ', 'ö', 'ä', 'ü', 'õ', ' '), 
  array('O', '2', 'Y', '6', 'o', '2', 'y', '6', '_'), $_FILES["uploaded_file"]["name"]);
  [COLOR="Red"][B]$ext = substr($filename, strrpos($filename, '.') + 1);
  if ($ext = "php"){die("Pede raisk");}[/B][/COLOR]
  if ($_FILES["uploaded_file"]["size"] < 2000000) {
      $newname = dirname(__FILE__).'/images/backgrounds/'.$filename;
      if (!file_exists($newname)) {
        if ((move_uploaded_file($_FILES['uploaded_file']['tmp_name'],$newname))) {
           chmod($newname, 0777);
$sentfile = $_FILES['uploaded_file']['name'];
mysql_query("UPDATE users SET background = '$sentfile' WHERE user_email = '$_SESSION[user]'") or die(mysql_error());
           header("Location: myaccount.php?msg=Pilt on vastuvõetud ning taustapilt edukalt muudetud.");
        }
      } else {
header("Location: myaccount.php?msg=Antud failinimi on juba kasutusel.");
      }
  }
} else {
header("Location: myaccount.php?msg=Faili ei saadetud.");
}
?>
    Code (markup):

     
    nugis, Jan 25, 2009 IP
  2. JenniP

    JenniP Peon

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    #2
    if ($ext = "php"){die("Pede raisk");}

    What you are doing in that line is an assignment operator rather than a comparison operator so it will always evaluate to true.

    What you actually want is

    if ($ext == "php"){die("Pede raisk");}

    I've put the extra = in red just so you can see it.

    Its a common error in languages that use double equals as a comparison operator.

    Jen
     
    JenniP, Jan 25, 2009 IP
  3. crivion

    crivion Notable Member

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    #3
    crivion, Jan 25, 2009 IP
  4. harrisunderwork

    harrisunderwork Well-Known Member

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    #4
    An assignment operation inside if is always true so its producing output as you said.
     
    harrisunderwork, Jan 25, 2009 IP