Web Content Filtering concerning specific URLs

Kurt Slesvig

Window 10 firewall manage IP addresses only.

I need it to block any outbound call with certain URL strings in either:

1) path example: /sys/loius.php

search 2) variable name or 3) variable content example: ?qweit= ... &...=paris

But how in C# programming can all internet calls be trapped and controlled?

3 Replies

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Mageshwaran R6y ago
Hi ,
please refer this link:
https://docs.microsoft.com/en-us/windows/security/threat-protection/microsoft-defender-atp/web-content-filtering
Kurt Slesvig6y ago
But MessageBox.Show("Site Blocked"); intends to block site, and that will not do. The IP address is still useful; so if windows firewall API can only block IPs, it's insufficient.

It has to run as a windows service and filter internet calls, checking each URL to redirect certain eh.. mistakes.
Sachin Singh6y ago
You should use windows Firewall API , however you can always block sites by writing it in hosts
Uri uri = new Uri("http://www.yoursite.com/sys/loius.php");
if (uri.Host.ToLower().EndsWith("yoursite.com"))
{
    // Do something
}

if(uri.AbsolutePath=="/sys/loius.php")
{
String path = @"C:\Windows\System32\drivers\etc\hosts";
        StreamWriter sw = new StreamWriter(path, true);
        String sitetoblock = "\n 127.0.0.1"+uri.Host;
        sw.Write(sitetoblock);
        sw.Close();
        MessageBox.Show("Site Blocked");
}
if (uri.PathAndQuery=="/Sys/loius.php/?qweit= ... &...=paris")
{
String path = @"C:\Windows\System32\drivers\etc\hosts";
        StreamWriter sw = new StreamWriter(path, true);
        String sitetoblock = "\n 127.0.0.1"+uri.Host;
        sw.Write(sitetoblock);
        sw.Close();
        MessageBox.Show("Site Blocked");
}