magnet links not working with socks5 proxy servers

[sdfgdhj]

I'm using qBitorrent with a socks5 proxy server. Magnet links stopped working a few days ago. It only works if you download the torrent instead of the magnet link.

[Peter]

Magnet links should not work with SOCKS5 at all.
Because magnet links work like this:
- it contains the metadata
- and you download the .torrent from other peers

But since SOCKS5 renders you passive, magnet links should not have worked like ever with it.

[sdfgdhj]

Thanks for the explanation. I've been using qBittorrent successfully with magnet links and SOCKS5 for 10+ years so I was confused when it suddenly stopped working last week.

[Peter]

Maybe your SOCKS5 proxy was not enabled/was not working ever?
Honestly, it can happen and it's impossible to safeguard against.
With VPN (using specific interfaces like OpenVPN), you can bind against your VPN interface, there is no such thing with SOCKS5.

[bob2306]

sdfgdhj wrote:
> Thanks for the explanation. I've been using qBittorrent successfully with
> magnet links and SOCKS5 for 10+ years so I was confused when it suddenly
> stopped working last week.

That explanation wasn't right, you don't need incoming connections for this to work.

If nothing else has changed on your side I suggest you take it up with the proxy provider.

[Peter]

bob2306 wrote:
> That explanation wasn't right, you don't need incoming connections for this to work.

How else would you have direct connections without incoming connections? Oo

[LilTroy]

If the SOCKS5 protocol is fully supported by the client and the proxy server then there's no reason why magnet links wouldn't work. Inbound connections, which I don't believe are necessary here, have always existed in SOCKS since version 4. Instead of acting purely as a forward proxy, which is the default behavior, it also allows for reverse proxying. For TCP connections this is done via the 'BIND' method. For UDP, which only SOCKS5 supports, it's done via 'UDP Associate'. The latter is more useful for torrenting. qBittorrent supports it or at least it did last I checked. However, I also know that its native SOCKS5 client implementation has had many bugs filed against it in the past. I don't know how well it works today since I'm a VPN user.

[bob2306]

Peter wrote:
> bob2306 wrote:
> > That explanation wasn't right, you don't need incoming connections for this to
> work.
>
> How else would you have direct connections without incoming connections? Oo

The same as most things do, by using the connection bidirectionally.