How do you detect a VPN or Proxy connection? [closed]

Answer 1

At IPinfo we offer a privacy detection API, which will let you know if a connection is coming from a VPN, an anonymous proxy, a tor exit node, or a hosting provider (which could be used to tunnel traffic). Here's an example:

$ curl ipinfo.io/43.241.71.120/privacy?token=$TOKEN
{
    "vpn": true,
    "proxy": false,
    "tor": false,
    "hosting": true
}

If you wanted to block connections to your site from VPNs then you could make an API request to get this information, and reply with an error if it's detected as a VPN. In PHP that would look something like this:

$ip = $_SERVER['REMOTE_ADDR'];
$url = "http://ipinfo.io/{$ip}/privacy?token={$IPINFO_API_TOKEN}";
$details = json_decode(file_get_contents($url));
// Just block VPNs
if($details->vpn) { 
    return echo "VPN Access Blocked!";
}

// Or we could block all the other types of private / anonymous connections...
if($details->vpn || $details->proxy || $details->tor || $details->hosting) { 
    return echo "Access Blocked!";
}