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Anonymouse web proxy can be detected using "HTTP_X_FORWARDED_FOR" with other similar tags including some array using ports definitions though it is not 100% efficient. But I have heard that "Elite Proxy Server" cannot be detected at all. Is it true ? or is there any loophole in it, so that some code using PHP can be used to detect Elite Proxy server. Does anyone can give tips about it? Anyone tried using some PHP code to detect it? Or is there any special software that can be uploaded in our server. Please help. Thanks

Thank you for you timely response in explaining me the drawback of using cookie as the basis for blocking login attempts. Your suggestion of using IP address to do this is correct. But can you give some tips as to how to go about it with some php codes? thanks

The index.php is used to login to my admin panel to create forms myself. But this admin login needs brute-force protection. So I decided to limit the number of login attempts to 3. I tried the code below but could not get it work The Code I tried is: (Login limit code) if($login_incorrect){ if(isset($_COOKIE['login'])){ if($_COOKIE['login'] < 3){ $attempts = $_COOKIE['login'] + 1; setcookie('login', $attempts, time()+60*10); //set the cookie for 10 minutes with the number of attempts stored } else{ echo 'You are banned for 10 minutes. Try again later'; } } else{ setcookie('login', 1, time()+60*10); //set the cookie for 10 minutes with the initial value of 1 } } The above code or similar code needs to be inserted in the index.php. Please see the index.php code below: if(!empty($_SESSION['logged_in']) && $_SESSION['logged_in'] == true){ header("Location: http{$ssl_suffix}://".$_SERVER['HTTP_HOST'].get_dirname($_SERVER['PHP_SELF'])."/manage_form.php"); exit; } if(!empty($_POST['submit'])){ $username = trim($_POST['admin_username']); $password = trim($_POST['admin_password']); if(($username != ADMIN_USER) || ($password != ADMIN_PASSWORD)){ $_SESSION['AP_LOGIN_ERROR'] = 'Please enter the correct user and password!'; }else{ $_SESSION['logged_in'] = true; if(!empty($_SESSION['prev_referer'])){ $next_page = $_SESSION['prev_referer']; unset($_SESSION['prev_referer']); header("Location: http{$ssl_suffix}://".$_SERVER['HTTP_HOST'].$next_page); exit; }else{ header("Location: http{$ssl_suffix}://".$_SERVER['HTTP_HOST'].get_dirname($_SERVER['PHP_SELF'])."/manage_form.php"); exit; } } } if(!empty($_GET['from'])){ $_SESSION['prev_referer'] = base64_decode($_GET['from']); } $hide_nav = true; ?>] I don't know where to insert the " login limit code" in the index.php Also it seems that the "login limit code" definitions doesn't match with definitions of the code in the index.php. I am stuck up at this point not knowing how to alter the "Login limit code" and insert it in appropriate place in the index.php. Please read both the codes above and help me implement it to work. Expecting someone to solve it. Thanks

Thank you for giving the above code. Can we use SMTP in the contact form processor instead of normal mail to () function. If you could read the full mail processor code i mentioned above, you can easily help me insert SMTP. Please do the needful. Thank you.

How to set Return-Path header in my above posted code? Can you just post the code here please? If using SMTP in the PHP will fix junk folder problem? If so, what SMTP Code must be inseted in the above form? Thank you.

This the PHP code that send mail: $where_form_is="http://".$_SERVER['SERVER_NAME'].strrev(strstr(strrev($_SERVER['PHP_SELF']),"/")); session_start(); // FIELD VALIDATION . . . if( validEmail($e_mail) == true ) { // address ok } else { // address bad } if( ($_SESSION['security_code']==$_POST['security_code']) && (!empty($_POST['security_code'])) ) { $from_email = $_POST['field_3'];$headers = 'From: ' . $from_email . "\r\n". 'Reply-To:'.$from_email; if(isset($_POST['url']) && $_POST['url'] == '') if(isset($_POST['fax']) && $_POST['fax'] == '') // then send the form to your email mail("test@testmail.com","Form submission","Form data: Date: ".date('l dS \of F Y h:i:s A')." Form Submitted from User IP : " . $_POST['ip'] . " Name: " . $_POST['field_1'] . " Website URL: " . $_POST['field_2'] . " Email: " . $_POST['field_3'] . " Phone: " . $_POST['field_4'] . " Fax: " . $_POST['field_5'] . " Country: " . $_POST['field_6'] . " Place/City: " . $_POST['field_7'] . " Subject: " . $_POST['field_8'] . " Message: " . $_POST['field_9'] . " ","$headers"); header("Location:http://www.test.com/folder/thankyou"); exit(); } else { echo "Invalid Captcha String."; } Please Help. Thank you. How to incorporate SPF DNS in this form?

I have a contact form that is processed by PHP and send email. The email php processor has the following code: $from_email = $_POST['field_2'];$headers = 'From: ' . $from_email . "\r\n". 'Reply-To:'.$from_email; mail("test@testmail.com", "Subject", "body of message"); All mails land up mostly in junk folder only. How do we make it to land up in Inbox. Please help to fix it. Thank you.

I understood that your code has nothing to do with Captcha. It would validate the form well and help processing securely. Your help is really great for me. I will be implementing your code soon. Shall I clarify my doubts with you if there is any difficulty in implementing the same? And there won't be any need to use Captacha also as you said. But I asked you about it because, when there is an acute necessity to implement Captcha we can do it only for those who send repeated mails. I also need to use another separate form that sends data to MYSQL database instead of Email. So I thought of taking addtional precautions. Could you please help me out to protect MYSQL Databse from hackers. I inserted mysql_real_escape_string in PHP. But not sure about it. Is there any other thing or code that I have to do protect remote injection or hijack attacks in MYSQL. Because earlier I had a form with Captcha(now removed due to attacks) that would send data to MYSQL . One day someone deleted all the data from the database. There is no log that gives any details. How to protect against such attacks? How to automatically create log in a text file about all the activites, information such as browser details, IP Address, Date, Time stamps etc...of clients who use the form? Please help. Thank you.

That's really good news that there is no spam in 4 years of using a form with your code. Now I feel confident and relieved. Thanks a lot. May I ask you one additional step about Captcha? Captcha is a burden to a genuine user and also for people with visual and hearing problems. That is, Captcha must not be on the form when the user sends mail only once. In case of succesive attempts to send mail by the same user, Captcha should appear on the form from the second attempt onwards. I think this can be done by storing a unique ID in a hidden field or something similar and check if the form was already submitted. We cannot rely on IP address as everyone knows, the user may have Dynamic IP address or switches through a web proxy. I don't how to implement it. Can I use the code I mentioned above (generating Unique Token ID, I dont know if the code is correct), but how to modify it. Any idea please? Since you have very good exposure to PHP you can help me. Thanks again.

Thank you for an excellent code you mentioned to prevent Spam and validate Email address with MX records and DNS look up. Really worth and nice for sharing such a great code. It is really useful. Please tell me if those codes you mentioned must be inserted after the "session Start" function but before "Mail to" function tag in mail processor.php As we say Captcha box will also little bit help. But how to prevent someone from accessing the mail processor php with remote injection and manipulating techniques and defeat captcha itself and use the form from a remote location? After inserting your code will it be simply impossible for a spammer to use the form from remote location? Thanks again. Please help.

Thank you for your suggestion and link to captcha. But I have added captcha to the form already. But still worried about spoofing a form by a spammer. Will captcha prevent Spoofing? I feel it can be defeated by a spammer who manages to manipulate the saved form after viewing the source code. Am i missing anything here? please tell me.

The form sends Email just to me with user input data. The form has "Your Email field" the user has to input. There is no CC option in any of the forms. But I tried to strip out extra charaters in the email field to avoid remote injection of Bcc cc headers and relay email spam. I am not sure about this form about spoofing attack. The html form action tag goes to process.php. Since the user can notice this PHP file from the address bar he now knows the location of the action script, he can directly call this PHP from anywhere after manipulating the html form. Please help. Thank You.

I am very much concerned about preventing 'spoofed contact web form submissions'. I have a code that may prevent multiple form submissions. This is the code in form.php( actually it is form.html changed extension as php): /*** begin the session ***/ session_start(); /*** create the form token ***/ $form_token = uniqid(); /*** add the form token to the session ***/ $_SESSION['form_token'] = $form_token; Now we have to process it with mail processor.php as below:session_start(); /*** check all expected variables are set ***/ if(!isset($_POST['first_name'], $_POST['form_token'], $_SESSION ['form_token'])) { $message = 'Invalid Submission'; } /*** check the form tokens match ***/ elseif($_POST['form_token'] != $_SESSION['form_token']) { $message = 'Access denied'; } My doubt is this kind of generating unique token or unique Session ID will also prevent fake or spoofed form submission? After reading about spoofed contact forms in google links that, hackers could save a copy of " html form page source" and manipulate it, even spoofing 'HTTP_Referer Header' also, I am very much worried. Since my knowledge in PHP is very limited, please help me. I don't know if the above code will protect my Contact Form. I searched this topic in the forum and could not find any solution. Please tell me how to exactly protect contact forms against such attacks. Thank you.

Thank you for helping me to get Host name and to block known proxies

Thanks a lot in making me into the right concept about this topic "Web Proxy" and now I am very much clear from your explanation. What I meant "Future" is, if there is any loop hole to track the Real IP behind a web proxy it would be nice. But now its clear that, it is impossible as explained by you. But please help me to check the proxy's host name to block them or treat them less if required as you said. What code has to be inserted to check the host name. Can you please post it here? Thanks again.

Thank you for your answer. But in future there we should find some solution to get the real IP.

I have a working Contact form in PHP that sends IP address of the visitor along with the user filled data via email. The "form.php" has this code: $ip = ($_SERVER['X_FORWARDED_FOR']) ? $_SERVER ['X_FORWARDED_FOR'] : $_SERVER['REMOTE_ADDR'];The "form.php" calls "processor.php" on submit. But the above code only shows the Proxy IP address. I myself tested it by using free proxy server (proxy4free dot com) and the form result showed only the Proxy IP address. How to get the real or source IP address. Since I don't know PHP etc... I am in need of help from this forum. I am receiving several mails that are suspicious. I have CAPTCHA also in my form. Please help me. Thank you.