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Trezz
12-03-02, 11:46
Hi,

I'm a newbie and have a problem with a surfer who is getting his giggles from submitting invalid e-mail addy's to my email form. Once the email is submitted the surfer is taken to a d/l page. The d/l page is written in php, so even though you can bookmark the d/l page, if you return without submitting an email addy, it returns an error. So one must gain access via the e-mail form page.

Problem is this joker is taking up to 10 - 15 d/l of the file each day ( 260KB) work that out over a month & it turns into a major pain in the butt.

To stop this I have tried detering this surfer with a echo of his IP addy
on the d/l page & have given notice of this action under the e-mail
form, however after a few days, its started again.

Is there any way I can incorporate an e-mail syntax check - via the submitted domain's smtp mailserver, to see if this is a valid email addy?
emails being submitted are like : wdgwndge@verio.net & so on.

I have searched high & low,although I have found a couple for ASP have been unable to find for php. Any assistance on this is greatly appreciated, thank you :)


// define some settings
$to = "xxxxx@xxxxx.com" ;
$from = "xxxxx@xxxxx.com";


// make sure everything is filled in
if (!strlen($_POST["email"]))
die("You did not enter your e-mail!");


// construct the body
$body = "Name: $_POST[email]\n\n ";

// send the email
mail($to, $_POST["subject"], $body, "From: $to");

bcyde
12-27-02, 12:44
Sorry but I don't know if what you're asking for is possible. I could see some potential problems with trying to generate a spam list with a utility that just does a brute force search for email addresses.

Some things you may want to try:
-If the user has a static IP you may want to block check the IP, of course this is pretty easy to get around depending on how sophisticated he/she is.

-Have you tried contacting his/her ISP, maybe if you complain enough you can get them to warn or even remove service for this guy.

-Incorporate some type of email authentication scheme where a unique ID/email pair is created when someone signs up which is sent to the email and before downloading this must be confirmed by following a link, entering it in a form, etc.

Hope some of this helps.
-b