How to block spam mails in inbox using php

Question

I have coded a contact us form and its process page for one of my client in php

When a user submits the form a mail is generated and its redirected to my clients inbox

Here im getting a terrible hundreds of unknown spam mails at the end of the day, i don't know where it is generating from,

Due to this our website is in danger from being added in blacklist on google and other search engines

Can anyone please give me a solution to block this spam mails and also please find the attachment for my php mail code

Below is my php code

<?php
if($_SERVER['REQUEST_METHOD'] == "POST")
{
$email = $_POST["email"];

$to = "test@myaddress.com";

$cname = htmlentities(ucfirst($_POST['name']));

$subject = "Subject Comes here";

$body= "Name : ";
$body.= $cname;

$body .= "\nE-mail : ";
$body .= htmlentities($_POST['email']);

$body.= "\nMessage : ";
$body.= htmlentities($_POST['message']);

    function is_valid_email($email)
    {
        return preg_match('#^[a-z0-9.!\#$%&\'*+-/=?^_`{|}~]+@([0-9.]+|([^\s]+\.+[a-z]{2,6}))$#si', $email);
    }

function contains_bad_str($str_to_test) {
  $bad_strings = array(
                "content-type:"
                ,"mime-version:"
                ,"multipart/mixed"
        ,"Content-Transfer-Encoding:"
                ,"bcc:"
        ,"cc:"
        ,"to:"
  );

  foreach($bad_strings as $bad_string) {
    if(eregi($bad_string, strtolower($str_to_test))) {
      header('Location: status.php?status=failed');
    }
  }
}

function contains_newlines($str_to_test) {
   if(preg_match("/(%0A|%0D|\\n+|\\r+)/i", $str_to_test) != 0) {
    header('Location: status.php?status=failed');
   }
} 

if (!is_valid_email($email)) {
  header('Location: status.php?status=failed');
}

contains_bad_str($email);
contains_bad_str($subject);
contains_bad_str(body);

contains_newlines($email);
contains_newlines($subject);

$headers = "From: $email";
mail($to, $subject, $body, $headers);
header('Location: status.php?status=success');
}
?>

possible duplicate of [Blocking comment spam without using captcha](http://stackoverflow.com/questions/1577918/blocking-comment-spam-without-using-captcha) — Jonathon Reinhart, Aug 01 '13 at 06:44
`find the attachment for my php mail code` where is the code?? — swapnesh, Aug 01 '13 at 06:50

score 1 · Answer 1 · edited May 23 '17 at 11:49

1

Or use a hidden field that should stay empty. Spambots have the habit of filling all the input fields.

More about this here: How to prevent robots from automatically filling up a form?

edited May 23 '17 at 11:49

Community

1
1

answered Aug 01 '13 at 06:46

user2626301

36
3

score 0 · Accepted Answer · answered Aug 01 '13 at 06:43

0

Use captchas to prevent spam bots from abusing your contact form and to ensure that only human beings can use it.

answered Aug 01 '13 at 06:43

ciruvan

5,143
1
26
32

How to block spam mails in inbox using php

2 Answers2