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robotoid

Member

Registered: 2019-07-18

Posts: 15

[Solved] Torrent clients working despite firewall

Hello

I always install Networkmanager and Ufw on a fresh system, and then usually KTorrent as well. The other day I was trying out QBittorrent and Transmission and was surprised to see that they start downloading torrents without any added rules. Ufw status reads:

Status: active
Logging: on (low)
Default: deny (incoming), allow (outgoing), disabled (routed)
New profiles: skip

To                         Action      From
--                         ------      ----
6881/tcp (KTorrent)        ALLOW IN    Anywhere                  
4444/udp (KTorrent)        ALLOW IN    Anywhere                  
6881/tcp (KTorrent (v6))   ALLOW IN    Anywhere (v6)             
4444/udp (KTorrent (v6))   ALLOW IN    Anywhere (v6)

This occurs both on a laptop and in VMs. So I wonder why Ufw offers predefined rules for these programs if they just work anyway. Is this expected when using torrents (with DHT) or am I missing something with my firewall setup?

Cheers

Last edited by robotoid (2020-06-29 22:29:29)

jasonwryan

Anarchist

From: .nz

Registered: 2009-05-09

Posts: 30,426

Website

Re: [Solved] Torrent clients working despite firewall

vim /etc/ufw/applications.d/ufw-bittorent

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Registered Linux User #482438

robotoid

Member

Registered: 2019-07-18

Posts: 15

Re: [Solved] Torrent clients working despite firewall

Ok, I didn't know about the limitations of the status command. I can see from the wiki and the man page that the "known applications" are not just there for typing convenience but are in fact built-in rules, enabled by default.

Thanks