The 'SSL torrent' feature is not standardized. I.e. there are no BEP (BitTorrent Enhancement Proposals) associated with it, so we do not greatly encourage its usage as it will only work with libtorrent clients and derivatives. It will not work with other torrent clients that do not support the libtorrent specific implementation.
This PR aims to provide minimal support for those who need SSL torrents. Furthermore, it is intended that there will be no UI support (nor indication) of adding/creating SSL torrents.
* Prerequisites:
I omit the instructions of creating those files as the intended audience (experts & advanced users) should have no problem with it. All files are as follow:
1. Root (torrent publisher) certificate
2. Root private key
3. A .torrent file created with root certificate
5. Peer certificate (signed by the root certificate)
6. Peer private key
7. Diffie-Hellman parameters file
All files are stored in .pem format.
* Enable SSL torrent protocol in qbt
There are 2 hidden keys to put in qbt config file, under `[BitTorrent]` section:
1. `Session\SSL\Enabled`: set it to `true`.
2. `Session\SSL\Port`: set it to some unused port or omit the key entirely to let qbt pick one for you.
* Add an SSL torrent to qbt
The only way of adding an SSL torrent is via WebAPI. The `/api/v2/torrents/add` endpoint will support 3 additional parameters. You must provide them for an SSL torrent.
1. `ssl_certificate`: Contents of the peer certificate file (in PEM format).
2. `ssl_private_key`: Contents of the peer private key file.
3. `ssl_dh_params`: Contents of the Diffie-Hellman parameters file.
* Change the SSL parameters to a torrent
In case you provided wrong SSL parameters when adding a torrent, there is a new endpoint `/api/v2/torrents/setSSLParameters` that you can update the SSL parameters. The parameters (`ssl_*`) are the same as `/api/v2/torrents/add` endpoint.
* Query the SSL parameters of a torrent
There is a new endpoint `/api/v2/torrents/SSLParameters` that you can query the SSL parameters of a torrent.
References:
* https://www.libtorrent.org/manual-ref.html#ssl-torrents
* https://blog.libtorrent.org/2012/01/bittorrent-over-ssl/
PR #20338.
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Co-authored-by: Radu Carpa <radu.carpa@cern.ch>
