| 22 May 2025 |
 Zhaofeng Li |
the ACLs have to be enforced by everyone
but now there's no built-in "block together"-like mechanism, right?
| 07:08:19 |
|  ayyz12 joined the room. | 07:08:31 |
| Zhaofeng Li | (I imagine the personal homeservers being the most difficult to get on board with such things) | 07:09:38 |
| Zhaofeng Li | *
the ACLs have to be enforced by everyone
but now there's no built-in "block together"-like mechanism, right? welp, I actually thought it was something like homeserver-level ACLs that block federation entirely
| 07:13:51 |
 f0x | In reply to @uep:matrix.org
image cache storage is of course an entirely separate problem and there's no garbage collection there there is? https://element-hq.github.io/synapse/latest/admin_api/media_admin_api.html#purge-remote-media-api | 07:14:22 |
 Cat | Turning off federation wholesale at room creation is also a thing. | 07:14:55 |
| Cat | But yes you can also enable allow list federation on a room level via ACL. | 07:15:09 |
| Zhaofeng Li | yeah, but it's not really practical | 07:15:42 |
| Zhaofeng Li | I know about the room-level homeserver ACLs, but they seem to me to be less effective than real homeserver bans | 07:16:41 |
| f0x | In reply to @zhaofeng:zhaofeng.li
I know about the room-level homeserver ACLs, but they seem to me to be less effective than real homeserver bans what would be the difference? | 07:18:26 |
| Cat | Matrix doesnt have de federation of that nature and it wont work due to how the protocol works. | 07:19:10 |
 Gnuxie 💜🐝 | In reply to @f0x:pixie.town
what would be the difference? the difference would be huge | 07:19:23 |
| Gnuxie 💜🐝 | lemme get you a link | 07:19:32 |
| Gnuxie 💜🐝 | @f0x:pixie.town https://github.com/matrix-org/matrix-spec-proposals/pull/4124 | 07:20:36 |
| Zhaofeng Li | I was thinking of activitypub/mastodon-style bans - you don't need to add the blocklist to each room and just ignore anything with a sender from the blocked homeservers | 07:21:07 |
| Zhaofeng Li | (i.e., blocked applied by homeserver admins, not room admins) | 07:21:27 |
| Zhaofeng Li | * (i.e., blocks applied by homeserver admins, not room admins) | 07:22:57 |
| f0x | In reply to @zhaofeng:zhaofeng.li
I was thinking of activitypub/mastodon-style bans - you don't need to add the blocklist to each room and just ignore anything with a sender from the blocked homeservers I think the best you could do is automatically setting server-acl (ish) things on all rooms your users have permission to. There's a fundamental difference with ActivityPub in how a block needs to affect other users/servers: AP servers are free to not send events to arbitrary other servers, and hide/drop events from blocked servers, but this approach doesn't work well in a shared chatroom, especially when it needs server cooperation to arrive at a shared room state | 07:28:59 |
| f0x | In reply to @gnu_ponut:matrix.org
@f0x:pixie.town https://github.com/matrix-org/matrix-spec-proposals/pull/4124 right, that's less about homeserver bans though, and rather a mechanism to allow for pre-screening? | 07:31:14 |
| Gnuxie 💜🐝 | In reply to @f0x:pixie.town
right, that's less about homeserver bans though, and rather a mechanism to allow for pre-screening? it's both | 07:31:36 |
| f0x |
We will embed m.server.knock_rule in m.room.create if it someone raises
small error 'it someone'
| 07:31:37 |
| Gnuxie 💜🐝 | oki | 07:32:19 |
| f0x | In reply to @gnu_ponut:matrix.org
it's both ah yeah, by making it explicit which servers are allowed to interact with the room | 07:34:24 |
| Zhaofeng Li |
this approach doesn't work well in a shared chatroom, especially when it needs server cooperation to arrive at a shared room state
It's ugly theoretically (homeservers may never converge to the same state), but in practice it may not be that bad?
| 07:39:02 |
| Zhaofeng Li | right now servers are already missing events naturally and having different views of the room state | 07:39:25 |
|  embr joined the room. | 07:40:26 |
 emily | that results in really bad things though | 07:40:39 |
| emily | silent netsplits that make us replace rooms | 07:40:53 |
|  cryptix joined the room. | 07:59:37 |
 uep | In reply to @f0x:pixie.town
there is? https://element-hq.github.io/synapse/latest/admin_api/media_admin_api.html#purge-remote-media-api yes, that's a purge of all remote media, not a garbage collection of media no longer referenced because the events have been redacted. Still works (assuming you weren't hosting the spammer), but: requires action on each server, and is an overly-blunt instrument. | 08:00:50 |
