Behaviour of restricted rooms with no valid conditions is not clear

[Kladki]

Link to problem area:

https://spec.matrix.org/v1.10/client-server-api/#restricted-rooms

Issue:

Currently, the spec states that:

If the room is restricted but no valid conditions are presented then the room is effectively invite only.

The problem here is that there seems to be multiple interpretations of this, those being:

• Taking this literally, using the exact rules of invite join rule when this is the case
• Taking this as a figure of speech, as for the most the room should act as if it was invite, since servers shouldn't ever authorize joins

The key difference between these two cases is that with the latter, a join can still be authorized via join_authorised_via_users_server, despite the fact that servers shouldn't be doing this. With the former, such a join wouldn't be authorized.

So which interpretation does the spec intend to abide by?

[clokep]

Taking this as a figure of speech, as for the most the room should act as if it was invite, since servers shouldn't ever authorize joins

It is not literal, it is meant to explain in normal words what happens if you fail to define any conditions.

The key difference between these two cases is that with the latter, a join can still be authorized via join_authorised_via_users_server, despite the fact that servers shouldn't be doing this. With the former, such a join wouldn't be authorized.

I don't think this was really considered, but I think the logic still holds up -- the user in join_authorised_via_users_server could have issued an invite so I don't think there's an "auth leak" of any sort. Shout if I'm wrong though!

[Kladki]

It is not literal, it is meant to explain in normal words what happens if you fail to define any conditions.

As I thought. I will try adjust the wording, since there was some confusion caused by this.