Netgate SG-1000 microFirewall

Author Topic: Need to block PSIPhon app  (Read 1405 times)

0 Members and 1 Guest are viewing this topic.

Offline myhome

  • Newbie
  • *
  • Posts: 5
  • Karma: +0/-0
    • View Profile
Need to block PSIPhon app
« on: September 18, 2015, 05:23:35 am »
I have tried

  - Forced users to use my DNS server
  - Created rules to block VPN, IPSEC, PPTP, SSH and L2TP

Any suggestions !!

Offline KOM

  • Hero Member
  • *****
  • Posts: 5609
  • Karma: +688/-23
    • View Profile
Re: Need to block PSIPhon app
« Reply #1 on: September 18, 2015, 09:01:27 am »
To block an application, you need to determine at least one of the following:

1) the server(s) the app talks to
2) the port(s) the app uses to talk

This app appears to use common web ports, so blocking that way isn't practical.  Next you try to see where this app tries to talk to and block all of those destination IPs.  You can't do it based on domain names because it most likely resolves to one of many different IP addresses, and DNS resolution doesn't happen in realtime for every domain requested.  SO you're left playing whack-a-mole with IP addresses.

A better way would be to have a clear usage policy, and suspend any users caught breaking the policy.  Users can always find a way around filters.

Offline ahmed.bayoumi

  • Newbie
  • *
  • Posts: 3
  • Karma: +0/-0
    • View Profile
Re: Need to block PSIPhon app
« Reply #2 on: March 21, 2017, 04:15:01 am »
you have to block DNS port 53
this worked for me if you are blocking 80 and 443 as well
https://doc.pfsense.org/index.php/Blocking_DNS_queries_to_external_resolvers 

Offline MR-NT

  • Newbie
  • *
  • Posts: 23
  • Karma: +0/-1
    • View Profile
Re: Need to block PSIPhon app
« Reply #3 on: January 28, 2018, 05:53:34 am »
Can you support us of how to you do it because i try what are you say but it didnt work