PHP - Does A Math Captcha Work, If Not, Why Not?

why does this not display my hosting supports gd

Code: [Select]
<?php
session_start();
create_image();

function create_image()
{
$rand = md5(rand(0, 9999999));
$vaule = substr ($rand, 10, 8);

//widht and height is the width of the box
$width = 150;
$height = 30;

//the will be ther sixe of the box
$image = imagecreate($width, $height);

$black = imagecolorallocate($image, 0, 0, 0);
$white = imagecolorallocate($image, 255, 255, 255);
$grey = imagecolorallocate ($image, 132, 132, 132);
$blue = imagecolorallocate ($image, 138, 197, 255);

//the bg of the image
imagefill($image, 0, 0, $blue);

//imagetext
imagestring($image, 5, 15, 7, $vaule, $black);

//middle line and down line
imageline($image, 0, $height/2, $width, $height/2, $grey);
imageline($image, $width/2, 0, $width/2, $height, $grey);
//hor line
image($image, 0, 0, $width, $height, $grey);
image($image, 0, $height, $width, 0, $grey);


//desplay image
imagepng($image);
imagedestroy($image);

//start session
$_SESSION[captcha_key];
}

?>

I want to build a captcha from scratch, as I'm all about doing things myself, and I've proposed a nice idea on how I can achieve that, but I'm sort of lost...

What I want to do is write a script that will generate a random string of both letters and numbers, with the ability to set a limit on how many characters are generated.  Then, I want to store that string within a variable called "random_string".

Once the user types in that code, their input would get captured in a separate php file and stored within a variable like so:
$captcha_code = $_POST['catpcha_code'];

Then, I would write a code to see if the user's input matches the random character string from the html:
Code: [Select]
<?php
if ($random_string == $captcha_code) {
mail($to, $subject, $body);
} else {
echo ("The code you entered did not match the captcha. Please go back and try again.");
}
?>
Is this possible? I haven't yet tried it myself, because I don't know how to generate random strings of characters, but I was just wondering if perhaps I'm on the right track? Any suggestions or advice is appreciated =)

Hello everybody, I am new to these forums and registered due to my problems which has been annoying me all the evening... I've been googling for 3 hours and still haven't found a proper answer.

The situation is:

I started to use session in my page.
<?php
ini_set('session.use_cookies', 0);
ini_set('session.use_only_cookies', 0);
ini_set('session.name', 'sid');
ini_set('session.auto_start', 0);
ini_set('session.use_trans_sid', 1);
session_start();
?>
these lines are included in, let's say, my register.php file.
(please, don't recommend me cookies as i'm developing a site for mobiles)

And then, there is a form:
<?php
echo '<form action="register.php?sid='.session_id().'" method="POST">
Įveskite kodą:<br/>
<input class="input" type="text" name="captcha" maxlength="4"/><br/>
<img id="captcha" src="captcha.php?sid='.session_id().'" /><br/>
<input type="submit" name="submit" value="Registruotis" /><br/>
</form>';?>

although captcha is shown, when I submit the form and i have to check inputs I get this error:

Notice: Undefined index: randomnr2 in C:\Program Files\EasyPHP-5.3.3.1\www\new\register.php on line 144

Well, my captcha.php file:

<?php

   $randomnr = rand(1000, 9999);
   $_SESSION['randomnr2'] = $randomnr;
   
   $im = imagecreatetruecolor(100, 38);
 
   $white = imagecolorallocate($im, 255, 255, 255);
   $grey = imagecolorallocate($im, 150, 150, 150);
   $black = imagecolorallocate($im, 0, 0, 0);
 
   imagefilledrectangle($im, 0, 0, 200, 35, $black);

   //path to font - this is just an example you can use any font you like:
   
   $font = dirName(__FILE__).'/font/karate/Karate.ttf';

   imagettftext($im, 20, 4, 22, 30, $grey, $font, $randomnr);
 
   imagettftext($im, 20, 4, 15, 32, $white, $font, $randomnr);
    
   //prevent caching on client side:
   header("Expires: Wed, 1 Jan 1997 00:00:00 GMT");
   header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
   header("Cache-Control: no-store, no-cache, must-revalidate");
   header("Cache-Control: post-check=0, pre-check=0", false);
   header("Pragma: no-cache");
 
   header ("Content-type: image/gif");
   imagegif($im);
   imagedestroy($im);
?>


Any ideas? Thanks in advance.

hi ,frds i am getting trouble .
here is my problem
captcha is working fine in firefox 3.6.16
but not in IE6

help me frds.

Can anyone please take a quick glance at this form the captcha messages are not appearing correctly. The message keeps getting sent.

Thank You

Code: [Select]
<?php
  if(($_SESSION['security_code'] != $_POST['security_code']) || (empty($_SESSION['security_code'])) ){


$to       = "info@*******.com"; // change to your email address
$name     = htmlentities ($_POST['name']);
$email    = htmlentities ($_POST['email']);
$phone    = htmlentities ($_POST['phone']);
$msg      = htmlentities ($_POST['msg']);
$d        = date('l dS \of F Y h:i:s A');
$sub      = "form to mail";
$headers  = "From: $name <$email>\n";  
$headers .= "Content-Type: text/plain; charset=iso-8859-1\n";
$mes      = "phone: ".$phone."\n";
$mes     .= "Message: ".$msg."\n";
$mes     .= "Name: ".$name."\n";
$mes     .= 'Email: '.$email."\n";
$mes     .= 'Date & Time: '.$d;
{
     mail($to, $sub, $mes, $headers);
 
}
echo "<p>&nbsp;</p><p>&nbsp;</p><p>&nbsp;</p><br />CAPTCHA CODE does not match! <p>&nbsp;</p><p>&nbsp;</p><a href='javascript:javascript:history.go(-1)'>Click here to go back to previous page</a>";
  }
  else 
  echo "THANK YOU";
  

?>

This is my first captcha script...it has 2 files, check.php and insert.php
It works fine but I would like to hear your opinion what can I do to make it better? Is there any way that I can add random images ?
Here is insert.php
Code: [Select]
<html>
<body>
<form action="check.php" method="post">
<img src="captcha.jpg"/>
Insert captcha: <input type="text" name="cap"/>
<input type="submit" value="submit"/>
</form>
</body>
</html>

here is check.php
Code: [Select]
<html>
<body>
<?php
$cap= "flirc";
if ($_POST["cap"]==$cap) echo "Captcha is right!";
else echo " Captcha is wrong! ";
?>
</body>
</html>It is pretty basic, I know
You can see it in action here

Hi,

I really need to add a captcha to this PHP process form?

How do I go about doing this?

Code: [Select]
<?php

// Define some constants

define( "RECIPIENT_NAME", "John Smith" );

define( "RECIPIENT_EMAIL", "john@example.com" );

define( "EMAIL_SUBJECT", "Visitor Message" );

// Read the form values

$success = false;

$senderName = isset( $_POST['senderName'] ) ? preg_replace( "/[^\.\-\' a-zA-Z0-9]/", "", $_POST['senderName'] ) : "";

$senderEmail = isset( $_POST['senderEmail'] ) ? preg_replace( "/[^\.\-\_\@a-zA-Z0-9]/", "", $_POST['senderEmail'] ) : "";

$message = isset( $_POST['message'] ) ? preg_replace( "/(From:|To:|BCC:|CC:|Subject:|Content-Type:)/", "", $_POST['message'] ) : "";

// If all values exist, send the email

if ( $senderName && $senderEmail && $message ) {

  $recipient = RECIPIENT_NAME . " <" . RECIPIENT_EMAIL . ">";

  $headers = "From: " . $senderName . " <" . $senderEmail . ">";

  $success = mail( $recipient, EMAIL_SUBJECT, $message, $headers );

}

// Return an appropriate response to the browser

if ( isset($_GET["ajax"]) ) {

  echo $success ? "success" : "error";

} else {

?>

<html>

  <head>

    <title>Thanks!</title>

  </head>

  <body>

  <?php if ( $success ) echo "<p>Thanks for sending your message! We'll get back to you shortly.</p>" ?>

  <?php if ( !$success ) echo "<p>There was a problem sending your message. Please try again.</p>" ?>

  <p>Click your browser's Back button to return to the page.</p>

  </body>

</html>

<?php

}

?>
??

Thanks in advance!

Code: [Select]
<?php
/* 
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
$width=120;
$height=60;
$image=  imagecreate($width, $height);
$txt=substr(md5(rand()),0,8);

$white=  imagecolorallocate($image, 255, 255, 255);
$black=  imagecolorallocate($image, 0, 0, 0);
$red=  imagecolorallocate($image, 255, 0, 0);
$new=  imagecolorallocate($image, 128, 128, 255);

//imagefilledrectangle($image, 10, 10, 110, 50, $white);
imagefilledrectangle($image, 20, 20, $width-20, $height-20, $new);

imagestring($image, 40, 27, 22, $txt, $black);
header("content-type:image/jpeg");
imagejpeg($image);
imagedestroy($image);
?>

Hi,

I need help in my code. I have written a CAPTCHA code, but it is not appearing when I test run in my website. My code is below, could anyone highlight to me my error? Any problems to those that were highlighted in red? Thanks

<?php
  session_start();

  // Set some important CAPTCHA constants
  define('CAPTCHA_NUMCHARS', 6);  // number of characters in pass-phrase
  define('CAPTCHA_WIDTH', 100);   // width of image
  define('CAPTCHA_HEIGHT', 25);   // height of image

  // Generate the random pass-phrase
  $pass_phrase = "";
  for ($i = 0; $i < CAPTCHA_NUMCHARS; $i++) {
    $pass_phrase .= chr(rand(97, 122)); //chr(), convert a number to its ASCII character equivalent
  }

  // Store the encrypted pass-phrase in a session variable
  $_SESSION['pass_phrase'] = SHA($pass_phrase);

  // Create the image
  $img = imagecreatetruecolor(CAPTCHA_WIDTH, CAPTCHA_HEIGHT);

  // Set a white background with black text and gray graphics
  $bg_color = imagecolorallocate($img, 255, 255, 255);     // white
  $text_color = imagecolorallocate($img, 0, 0, 0);         // black
  $graphic_color = imagecolorallocate($img, 64, 64, 64);   // dark gray

  // Fill the background
  imagefilledrectangle($img, 0, 0, CAPTCHA_WIDTH, CAPTCHA_HEIGHT, $bg_color);

  // Draw some random lines
  for ($i = 0; $i < 5; $i++) {
    imageline($img, 0, rand() % CAPTCHA_HEIGHT, CAPTCHA_WIDTH, rand() % CAPTCHA_HEIGHT, $graphic_color);
  }

  // Sprinkle in some random dots
  for ($i = 0; $i < 50; $i++) {
    imagesetpixel($img, rand() % CAPTCHA_WIDTH, rand() % CAPTCHA_HEIGHT, $graphic_color);
  }

  // Draw the pass-phrase string
  imagettftext($img, 18, 0, 5, CAPTCHA_HEIGHT - 5, $text_color, 'Courier New Bold.ttf', $pass_phrase);

  // Output the image as a PNG using a header
  header("Content-type: image/png");
  imagepng($img);

  // Clean up
  imagedestroy($img);
?>

I wrote a small PHP with SQLite script which stores the IP with counter, it works fine with one problem, If I enter the correct password 4th time the counter becomes 4 and I get the error to enter my captcha. All the other times, 1-3 and 5 and above count it just works fine. What am I doing wrong with the logic.   Attaching the zip file with code.   https://drive.google...dit?usp=sharing

Hi I have a script below which I have put together from a couple of other scripts which simply adds an email address to a database for a newsletter and sends an email to the owner and to the user it then shows a success page.
The script checks that the email is valid and there is also a captcha.
The script works in that it only send out the emails if the captcha etc is entered correctly but the email is being added to the database regardless of whether the capture is correct or not. I was proud of myself for getting this far but would love some instruction on what I have missed and how to stop the email adding to the database unless it has passed the captcha.

Below you will see the script. The commented out sections are parts of the old script I don't use.


<?php

  require('includes/application_top.php');

  require(DIR_WS_LANGUAGES . $language . '/' . FILENAME_TESTING);

  $error = false;
  if (isset($HTTP_GET_VARS['action']) && ($HTTP_GET_VARS['action'] == 'send')) {
    //$name = tep_db_prepare_input($HTTP_POST_VARS['name']);
    $email_address = tep_db_prepare_input($HTTP_POST_VARS['email']);
    //$enquiry = tep_db_prepare_input($HTTP_POST_VARS['enquiry']);

    if (tep_validate_email($email_address) == false) {
      $error = true;
      $messageStack->add('testing', ENTRY_EMAIL_ADDRESS_CHECK_ERROR);
    }

//CAPTHCA CODE start
  require(DIR_WS_FUNCTIONS . 'capcha_code.php');

    $code_query = tep_db_query("select code from capcha_code where oscsid = '" . tep_session_id($HTTP_GET_VARS[tep_session_name()]) . "'");
    $code_array = tep_db_fetch_array($code_query);
    $code = $code_array['code'];

    tep_db_query("DELETE FROM " . TABLE_CAPCTHA_CODE . " WHERE oscsid='" . $vvcode_oscsid . "'"); //remove the visual verify code associated with this session to clean database and ensure new results

    $user_entered_code = $HTTP_POST_VARS['capcha_code'];
    if (!(strcasecmp($user_entered_code, $code) == 0)) {    //make the check case insensitive
        $error = true;
        $messageStack->add('testing', CAPCTHA_CODE_ENTRY_ERROR);
    }
//CAPTHCA CODE stop
 /* testing sign up start */

      if (isset($HTTP_POST_VARS['testing_sign_up']))
      {

        $testing_query = tep_db_query("select testing_id_number from " . 
          TABLE_TESTING_SIGN_UP . 
          " where testing_email_address = '" . 
          tep_db_input($email_address) . "'");

        if(tep_db_num_rows($testing_query) == 0)
        {
          $sql_data_array = array('testing_email_address' => $email_address,
                                  'testing_firstname' => "",
                                  'testing_lastname' => "");
          tep_db_perform(TABLE_TESTING_SIGN_UP, $sql_data_array);
        }
      }
      
/* testing sign up end */

    if ($error == false) {
         tep_mail(STORE_OWNER, STORE_OWNER_EMAIL_ADDRESS, EMAIL_SUBJECT, $email_address,STORE_OWNER_EMAIL_ADDRESS);
tep_mail(MESSAGE_TEXT, $email_address, CUSTOMER_SUBJECT, NUMBER_ONE, STORE_OWNER_EMAIL_ADDRESS);
         tep_redirect(tep_href_link(FILENAME_TESTING, 'action=success'));
    }
  }

  $breadcrumb->add(NAVBAR_TITLE, tep_href_link(FILENAME_TESTING));
?>
<!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN">
<html <?php echo HTML_PARAMS; ?>>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=<?php echo CHARSET; ?>">
<title><?php echo TITLE; ?></title>
<base href="<?php echo (($request_type == 'SSL') ? HTTPS_SERVER : HTTP_SERVER) . DIR_WS_CATALOG; ?>">
<link rel="stylesheet" type="text/css" href="stylesheet.css">
</head>
<body marginwidth="0" marginheight="0" topmargin="0" bottommargin="0" leftmargin="0" rightmargin="0">
<!-- header //-->
<?php require(DIR_WS_INCLUDES . 'header.php'); ?>
<!-- header_eof //-->

<!-- body //-->
<table border="0" width="100%" cellspacing="3" cellpadding="3">
  <tr>
    <td width="<?php echo BOX_WIDTH; ?>" valign="top"><table border="0" width="<?php echo BOX_WIDTH; ?>" cellspacing="0" cellpadding="2">
<!-- left_navigation //--> <?php require(DIR_WS_INCLUDES . 'column_left.php'); ?> 
<!-- left_navigation_eof //--> </table></td><!-- body_text //--> <td width="100%" valign="top"><?php echo tep_draw_form('testing', tep_href_link(FILENAME_TESTING, 'action=send')); ?><table border="0" width="100%" cellspacing="0" cellpadding="0"> 
<tr> <td><table border="0" width="100%" cellspacing="0" cellpadding="0"> <tr> 
<td class="pageHeading"><?php echo HEADING_TITLE; ?></td><td class="pageHeading" align="right"><?php echo tep_image(DIR_WS_IMAGES . 'table_background_contact_us.gif', HEADING_TITLE, HEADING_IMAGE_WIDTH, HEADING_IMAGE_HEIGHT); ?></td></tr>

</table>
</td></tr><td class="main"><?php echo INFORMATION_TEXT; ?></td>
<tr> 
<td><?php echo tep_draw_separator('pixel_trans.gif', '100%', '10'); ?></td></tr> 
<?php
  if ($messageStack->size('testing') > 0) {
?>
      <tr>
        <td><?php echo $messageStack->output('testing'); ?></td>
      </tr>
      <tr>
        <td><?php echo tep_draw_separator('pixel_trans.gif', '100%', '10'); ?></td>
      </tr>
<?php
  }

  if (isset($HTTP_GET_VARS['action']) && ($HTTP_GET_VARS['action'] == 'success')) {
?>
      <tr>
        <td class="main" align="left"><?php echo tep_image(DIR_WS_IMAGES . 'clever.gif', HEADING_TITLE, '0', '0', 'align="left"') . TEXT_COMPLETE; ?></td>
      </tr>
      <tr>
        <td><?php echo tep_draw_separator('pixel_trans.gif', '100%', '10'); ?></td>
      </tr>
      <tr>
        <td><table border="0" width="100%" cellspacing="1" cellpadding="2" class="infoBox">
          <tr class="infoBoxContents">
            <td><table border="0" width="100%" cellspacing="0" cellpadding="2">
              <tr>
                <td width="10"><?php echo tep_draw_separator('pixel_trans.gif', '10', '1'); ?></td>
                <td align="right"><?php echo '<a href="' . tep_href_link(FILENAME_DEFAULT) . '">' . tep_image_button('button_continue.gif', IMAGE_BUTTON_CONTINUE) . '</a>'; ?></td>
                <td width="10"><?php echo tep_draw_separator('pixel_trans.gif', '10', '1'); ?></td>
              </tr>
            </table></td>
          </tr>
        </table></td>
      </tr>
<?php
  } else {
?>
      <tr>
        <td><table border="0" width="100%" cellspacing="1" cellpadding="2" class="infoBox">
          <tr class="infoBoxContents">
            <td><table border="0" width="100%" cellspacing="0" cellpadding="2" >
              <!--<tr>
                <td class="main"><?php echo ENTRY_NAME; ?></td>
              </tr>
              <tr>
                <td class="main"><?php echo tep_draw_input_field('name'); ?></td>
              </tr>//-->
<tr><td class="main"><?php echo INSTRUCTIONS_TEXT; ?></td></tr>
 
              <tr>
                <td class="main"><?php echo ENTRY_EMAIL; ?>
             
               <?php echo tep_draw_input_field('email'); ?></td>
              </tr>


      <tr>
        <td><?php echo tep_draw_separator('pixel_trans.gif', '100%', '10'); ?></td>
      </tr>
              <!--<tr>
                <td class="main"><?php echo ENTRY_ENQUIRY; ?></td>
              </tr>
              <tr>
                
<td><?php echo tep_draw_textarea_field('enquiry', 'soft',
50, 15, $infotext);
?></td>
              </tr>//-->
<!-- CAPTHCA CODE-- START-->
      <tr>
        <td class="main"><?php echo CAPCTHA_CODE_CATEGORY; ?></td>
      </tr>
      <tr>
        <td><table border="0" width="100%" cellspacing="1" cellpadding="2" class="infoBox">
          <tr class="infoBoxContents">
            <td><table border="0" cellspacing="2" cellpadding="2">

              <tr>
                <td class="main"><?php echo CAPCTHA_CODE_TEXT_INSTRUCTIONS; ?></td>
                
                <td class="main">
                  <?php
              // ----- begin garbage collection --------
    tep_db_query("DELETE FROM " . TABLE_CAPCTHA_CODE . " WHERE dt < DATE_SUB(NOW(), INTERVAL 5 HOUR)");
// ----- end garbage collection --------

                      //can replace the following loop with $capcha_code = substr(str_shuffle (CAPCTHA_CODE_CHARACTER_POOL), 0, rand(3,4)); if you have PHP 4.3
                    $capcha_code = "";
                    for ($i = 1; $i <= rand(3,4); $i++){
                          $capcha_code = $capcha_code . substr(CAPCTHA_CODE_CHARACTER_POOL, rand(0, strlen(CAPCTHA_CODE_CHARACTER_POOL)-1), 1);
                     }
                     $vvcode_oscsid = tep_session_id($HTTP_GET_VARS[tep_session_name()]);
                     tep_db_query("DELETE FROM " . TABLE_CAPCTHA_CODE . " WHERE oscsid='" . $vvcode_oscsid . "'");
                     $sql_data_array = array('oscsid' => $vvcode_oscsid, 'code' => $capcha_code);
                     tep_db_perform(TABLE_CAPCTHA_CODE, $sql_data_array);
                     $capcha_code = "";
                     echo('<img src="' . FILENAME_CAPCTHA_CODE_DISPLAY . '?vvc=' . $vvcode_oscsid . '"');
                  ?>
                </td>
                <td class="main"><?php echo CAPCTHA_CODE_BOX_IDENTIFIER; ?></td>
<td class="main"><?php echo tep_draw_input_field('capcha_code'); ?></td>

              </tr>
            </table></td>
          </tr>
        </table></td>
      </tr>

<!-- testing sign up start//-->  
<TD WIDTH="100%"> 
<tr> <td class="main" align="right"><?php echo ENTRY_TESTING_SIGN_UP; ?> 
<?php echo tep_draw_checkbox_field('testing_sign_up', '1', true); ?>&nbsp;&nbsp;&nbsp;</td></tr> 
<!--testing sign up end //-->

<!-- CAPTHCA CODE-- STOP -->
                <td width="10"><?php echo tep_draw_separator('pixel_trans.gif', '10', '1'); ?></td> 
            </table></td>
          </tr>
        </table></td>
      </tr>
      <tr>
        <td><?php echo tep_draw_separator('pixel_trans.gif', '100%', '10'); ?></td>
      </tr>
      <tr>
        <td><table border="0" width="100%" cellspacing="1" cellpadding="2" class="infoBox">
          <tr class="infoBoxContents">
            <td><table border="0" width="100%" cellspacing="0" cellpadding="2">
              <tr>
                <td width="10"><?php echo tep_draw_separator('pixel_trans.gif', '10', '1'); ?></td>
                <td align="right"><?php echo tep_image_submit('button_continue.gif', IMAGE_BUTTON_CONTINUE); ?></td> 

                <td width="10"><?php echo tep_draw_separator('pixel_trans.gif', '10', '1'); ?></td>
              </tr>
            </table></td>
          </tr>
        </table></td>
      </tr>
<?php
  }
?>
    </table></form></td>
<!-- body_text_eof //-->
    <td width="<?php echo BOX_WIDTH; ?>" valign="top"><table border="0" width="<?php echo BOX_WIDTH; ?>" cellspacing="0" cellpadding="2">
<!-- right_navigation //-->
<?php require(DIR_WS_INCLUDES . 'column_right.php'); ?>
<!-- right_navigation_eof //-->
    </table></td>
  </tr>
</table>
<!-- body_eof //-->

<!-- footer //-->
<?php require(DIR_WS_INCLUDES . 'footer.php'); ?>
<!-- footer_eof //-->
<br>
</body>
</html>
<?php require(DIR_WS_INCLUDES . 'application_bottom.php'); ?>

I'm trying to login to a vBulletin forum using a captcha login. I am, however, not able to download the captcha image.

This is the result I get when I try to get the captcha:



So how do I get the captcha image?

This is my current login code:

Code: [Select]
<?php
$user='username';
$pass='password';
$md5Pass = md5($pass);
$data = "do=login&vb_login_md5password=$md5Pass&vb_login_md5password_utf=$md5Pass&vb_login_username=$user&cookieuser=1";

$ch = curl_init();

curl_setopt ($ch, CURLOPT_URL, "http://www.****.com/login.php?do=login");
curl_setopt ($ch, CURLOPT_USERAGENT, "Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)");
curl_setopt ($ch, CURLOPT_TIMEOUT, '10');
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch,CURLOPT_POSTFIELDS,$data);
curl_setopt($ch, CURLOPT_COOKIEJAR, "cookie.txt");
curl_setopt($ch, CURLOPT_COOKIEFILE, "cookie.txt");
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);

$store = curl_exec ($ch);
curl_close($ch);
echo $store;
?>

Maybe the site looks for a cookie and only shows the captcha if it finds the cookie file?

Ideally just one word authentication and pretty simple, but effective.
 
Preferebly one that does not use Sessions because then the user is unable to press the back button to go back to the original page after submitting the form... I know I could just put a text link there but not all users would click that link...

hi
i was wondering if anyone had any idea how i can add code A  to code b below? code a is my captcha code and code b is my contact form code thanks..

CODE A CAPTCHA:
Code: [Select]
<?php
if(isset($_POST["captcha"]))
if($_SESSION["captcha"]==$_POST["captcha"])
{
echo 'CAPTHCA is valid; proceed the message';
}
else
{
echo 'CAPTHCA is not valid; ignore submission';
}
?>
CODE B CONTACT FORM:
Code: [Select]
<?
$mailto = "me@blah.com";
$cc = "";
$bcc = "";
$subject = "Email subject";
$vname = "blah blah";
$email = $_POST['email'];
function validateEmail($email)
{
if(eregi('^[a-zA-Z0-9._-]+@[a-zA-Z0-9-]+\.[a-zA-Z]{2,4}(\.[a-zA-Z]{2,3})?(\.[a-zA-Z]{2,3})?$', $email))
return true;
else
return false;
}
if(strlen($_POST['name']) < 1  || strlen($_POST['message']) < 1 || validateEmail($email) == FALSE)
{
$emailerror = 'Error:';
if(empty($_POST['name']))
{
$emailerror .= '<li>Enter name</li>';
}
if(validateEmail($email) == FALSE)
{
$emailerror .= '<li>Enter valid email</li>';
}
if(empty($_POST['message']))
{
$emailerror .= '<li>Enter message</li>';
}
}
else
{
$emailerror .= "Your email has been sent successfully";
$timestamp = date("F j, Y, g:ia");
$messageproper ="\n\n" .
"Name: " .
ucwords($_POST['name']) .
"\n" .
"Email: " .
ucwords($email) .
"\n" .
"Comments: " .
$_POST['message'] .
"\n" .
"\n\n" ;
$messageproper = trim(stripslashes($messageproper));
mail($mailto, $subject, $messageproper, "From: \"$vname\" <".$_POST['e_mail'].">\nReply-To: \"".ucwords($_POST['first_name'])."\" <".$_POST['e_mail'].">\nX-Mailer: PHP/" . phpversion() );
}
?>

How effective is Captcha anymore?

How does using Captcha compare to using a Challenge Question like "2 + 3 = ??"

I am creating a form on my website where users can e-mail me their comments - although my e-mail is hidden - and I don't want this to become a spam-magnet?!   


Debbie