How to block all connections from Europe on a TCPListener

Question

Is there a simple way using a TCPListener in C# to block all incoming connections from the European continent? I need to do the following in order to decide whether or not to block a connection:

1. Determine client's location (if in Europe, proceed to step 2, otherwise, bypass the security check)
2. Read authentication token from client (session ID). If session ID indicates that the customer is a citizen of a non-European country, authorize the connection. Otherwise, close the NetworkStream immediately.

Answer 1

You could try polling using a C# GeoIP locator and doing a DNSBL list for your application (though I assume you're already doing such by asking this question).

Answer 2

You can check on an online database to check where the connection is comming from. Zack has given an link to MaxMind's IP locator.