Php code to add a fixed image (Captcha Kind) for form

Avoiding spam, ensuring human filled the form

[silverbytes]

I need to add a simple image with something like "2+2=" in order to humans filling my form type in a text field "4". I don't want a captcha but I need something similar easy to add to my form.

My php form page has something like this:

<form action="formokinsc.php" method="post" target="okinsc" onSubmit="YY_checkform('inscripcion','nombre','#q','0','Field \'nombre\' is not valid.','email','#S','2','Field \'email\' is not valid.','telefono','#q','0','Field \'telefono\' is not valid.','comonosencontro','#q','1','Field \'comonosencontro\' is not valid.');return document.MM_returnValue" value=Inscribirme>

My "Ok" page has something like this:

<?
//mime
foreach ( $_POST as $key => $value ) {
$postVars .= $value;
}

if(eregi("MIME-Version:",$postVars)) {
die('Your message containts the words
"MIME-Version:" this is considerd as spam!');
}

$sploited = 0;
foreach($_POST as $key=>$value){
if(preg_match("!bcc:.+@!" , $value , $sploit_matches)){
$sploited = 1;
}
}

// If the form has been exploited, return a 404
if($sploited){

header("HTTP/1.0 404 Not Found");
echo "<h1>404 - Not Found</h1>";
exit();

}
else{

//PROCESS VALID FORM DATA HERE

$formulario = "Title";
$emailreceptor = "[e-mail]";

$receptor .= "E-mail: $email\n";
$receptor .= "\n";

$receptor .= "name: $nombre\n";
$receptor .= "\n";

$receptor .= "Suscribir al newsletter: $suscribiranewsletter\n";
$receptor .= "\n";

$receptor .= "----------Información Remota----------\n";
$receptor .= "$HTTP_USER_AGENT\n";
$receptor .= "$REMOTE_ADDR\n";

mail("$emailreceptor", "$formulario", $receptor, "From: $email");

}
?>

May anybody suggestme some code line for my form page, and my ok page?

[dreamcatcher]

Hi silverbytes,

Firstly, generate two random numbers and store them in hidden vars:

<?php
$one = rand [uk.php.net](1,99);
$two = rand [uk.php.net](11,55);
?>

<input type="hidden" name="one" value="<?php echo $one;?>">
<input type="hidden" name="two" value="<?php echo $two;?>">

Then add a third field asking for user input:

<?php echo $one;?>+<?php echo $two;?> =<br />
<input type="text" name="sum">

Then when you process:

if ($_POST['one']+$_POST['two']!=$_POST['sum'])
{
//error
}

Hope that helps.

dc

[silverbytes]

I forgot to tell that my page with the form is .htm
is it possible to use that code on a .htm file?

Do I understand correctly if I assume all that code goes in form page and the final part on ok page: if ($_POST['one']+$_POST['two']!=$_POST['sum'])
{
//error
}

[dreamcatcher]

You`ve got a couple of options. You can point your form action to a .php page, where you can do your processing or use .htaccess to parse your .htm page as a .php page.

dc

[silverbytes]

Actually my page form points to formokinsc.php

If I put that code in my form page (.htm page)

<?php
$one = rand(1,99);
$two = rand(11,55);
?>

<input type="hidden" name="one" value="<?php echo $one;?>">
<input type="hidden" name="two" value="<?php echo $two;?>">

Then add a third field asking for user input:

<?php echo $one;?>+<?php echo $two;?> =<br />
<input type="text" name="sum">

And this in formokinsc.php

if ($_POST['one']+$_POST['two']!=$_POST['sum'])
{
//error
}

Would work?

I guess there isn't any tag to insert a piece of php code into an html page. Do I assume right?

What code should I add to .htaccess in order to parse my form.htm page as form.php page?

[dreamcatcher]

Yep, that should work ok. Just do the appropriate action if the sum isn`t correct. Give it a try and see what happens.

To parse your form.htm as form.php, add the following to your .htaccess file:

AddType application/x-httpd-php .php .htm

That should be fine assuming your server supports .htaccess

dc

[silverbytes]

Adding the code to the htm page does not produce results (it's not showing the random number) I guess the htm page doesn't "understand" the php code having a .htm extension.

I don't know if is there something like <script language="JavaScript" type="text/JavaScript"></script> but for php scripts...

[silverbytes]

Ok I changed the random for a fixed value and that part works, but the form doesn't indicate any error if you don't put the code and shows the success page.

So added this to the ok php page:

if ($_POST['one']+$_POST['two']!=$_POST['sum'])
{
//error
header("HTTP/1.0 404 Not Found");
echo "<h1>Error</h1>";
}

But that's the ok page, so what I'm saying is "error" but showind the success page... that's bad

How do I stop the ok page to show if they don't put the right security code?