Getting a User's IP Via PHP

[mattyd]

Hello,

I am wanting to collect the IP address of anyone that visits my site and submits a form (Saving it to my DB).

I have been researching this and have found the following:

`

<?php

    if (getenv('HTTP_X_FORWARDED_FOR')) {
        $pipaddress = getenv('HTTP_X_FORWARDED_FOR');
        $ipaddress = getenv('REMOTE_ADDR');
echo "Your Proxy IP address is : ".$pipaddress. "(via $ipaddress)" ;
    } else {
        $ipaddress = getenv('REMOTE_ADDR');
        echo "Your IP address is : $ipaddress";
    }
?>

`

Of couse, I would modify this code to allow it to post to my DB, not echo it for the User.

Is this a sound method or are there other methods?

Is there anything else in particular that I should be aware of?

Thank you,
Matthew

[JorgeM]

Yes, i'd use those two variables. THere are more if you want to try to collect other info..

http://php.net/manual/en/reserved.variables.server.php

im not really php developer, more like a php noob, but this is how i basically collect the same info in asp.net

[jj.dcruz]

The simplest way to get the visitor’s/client’s IP address is using the $_SERVER['REMOTE_ADDR'] or $_SERVER['REMOTE_HOST'] variables.

However, sometimes this does not return the correct IP address of the visitor, so we can use some other server variables to get the IP address.

The below both functions are equivalent with the difference only in how and from where the values are retrieved.

getenv() is used to get the value of an environment variable in PHP.

// Function to get the client IP address
function get_client_ip() {
    $ipaddress = '';
    if (getenv('HTTP_CLIENT_IP'))
        $ipaddress = getenv('HTTP_CLIENT_IP');
    else if(getenv('HTTP_X_FORWARDED_FOR'))
        $ipaddress = getenv('HTTP_X_FORWARDED_FOR');
    else if(getenv('HTTP_X_FORWARDED'))
        $ipaddress = getenv('HTTP_X_FORWARDED');
    else if(getenv('HTTP_FORWARDED_FOR'))
        $ipaddress = getenv('HTTP_FORWARDED_FOR');
    else if(getenv('HTTP_FORWARDED'))
       $ipaddress = getenv('HTTP_FORWARDED');
    else if(getenv('REMOTE_ADDR'))
        $ipaddress = getenv('REMOTE_ADDR');
    else
        $ipaddress = 'UNKNOWN';
    return $ipaddress;
}

$_SERVER is an array that contains server variables created by the web server.

// Function to get the client IP address
function get_client_ip() {
    $ipaddress = '';
    if ($_SERVER['HTTP_CLIENT_IP'])
        $ipaddress = $_SERVER['HTTP_CLIENT_IP'];
    else if($_SERVER['HTTP_X_FORWARDED_FOR'])
        $ipaddress = $_SERVER['HTTP_X_FORWARDED_FOR'];
    else if($_SERVER['HTTP_X_FORWARDED'])
        $ipaddress = $_SERVER['HTTP_X_FORWARDED'];
    else if($_SERVER['HTTP_FORWARDED_FOR'])
        $ipaddress = $_SERVER['HTTP_FORWARDED_FOR'];
    else if($_SERVER['HTTP_FORWARDED'])
        $ipaddress = $_SERVER['HTTP_FORWARDED'];
    else if($_SERVER['REMOTE_ADDR'])
        $ipaddress = $_SERVER['REMOTE_ADDR'];
    else
        $ipaddress = 'UNKNOWN';
    return $ipaddress;
}

note that this function can also lead you very wrong. in particular, HTTP_X_FORWARDED_FOR can be anything a client chooses to set, whereas REMOTE_ADDR is considerably harder to fake, if client wants to get the actual response