Image verification

[ted_chou12]

Hello, I don't understand why this code doesnt work:

<?php session_start();
//send img to header as jpg file
header('Content-type: image/jpeg');

//generate random string:
$alphanum = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
$string = substr(str_shuffle($alphanum), 0, 5);

//store in session (md5)
$_SESSION['imgverify'] = md5($string);

//create image from existing bgs
$bgno = rand(1, 4);
$image = imagecreatefromjpeg("images/background$bgno.jpg");

//white bg, black text
$bgcolor = imagecolorallocate($image, 255, 255, 255);
$textcolor = imagecolorallocate($image, 0, 0, 0);

//producing image (img, font, x, y, text, color)
imagestring($image, 5, 7, 8, $string, $textcolor);

imagejpeg($image);
imagedestroy($image);?>

and

<?php session_start();
//image verification passed?
if ($_SESSION['imgverify'] != md5($imgverify))
{echo $imgverify_failed; $invalid = true;}?>
<label>Image Verification</label>
<img id="image" src="imgverify.php" onclick="reloadImg();" />

But the $_SESSION['imgverify'] is not md5 encoded in the second page, I have no idea what's wrong, ???

Thanks,

Ted

[redarrow]

md5($imgverify) << where this defined mate.

[ted_chou12]

md5($imgverify); is defined from an form submission above these codes,

$imgverify = $_POST['imgverify'];

Ted

[ted_chou12]

bump...

[thebadbad]

Does $_SESSION['imgverify'] contain anything at all, at the second page? First thing to check.

[ted_chou12]

Yes, it has something, it's the uncoded string from the first page, but when i output the variable in the first page, the string is md5 coded ??? i have no clue why it's like this

[ted_chou12]

I found where the problem is, but i still have no clue why it is:

//on the second page, where the submission of image verify code is:
if (isset($_POST['submit'])){
$name = $_POST['name'];
$email = $_POST['email'];
$tname = $_POST['tname'];
$temail = $_POST['temail'];
$message = $_POST['message'];
$imgverify = $_POST['imgverify'];//after here the $_SESSION['imgverify'] suddenly turns to non md5 coded, but before this line $_SESSION['imgverify'] is fine.

I think this is a bug that ive found, i spent hours trying to look for this error, is so annoying...

[thebadbad]

Not that I'm sure it would matter, but do you have register_globals turned on?