Fixes a set of bugs introduced by 00b77144c1,
where we replaced explicit `RoomVersionId` matches with `version < V11`
comparisons. The `Ord` impl on `RoomVersionId` does not work like that,
and is in fact a lexicographic string comparison[1]. The most visible
effect of these bugs is that incoming redaction events would sometimes
be ignored.
Instead of reverting to the explicit matches, which were quite verbose,
I implemented a `RoomVersion` struct that has flags for each property
that we care about. This is similar to the approach used by ruma[2] and
synapse[3].
[1]: 7cfa3be0c6/crates/ruma-common/src/identifiers/room_version_id.rs (L136)
[2]: 7cfa3be0c6/crates/ruma-state-res/src/room_version.rs
[3]: c856ae4724/synapse/api/room_versions.py
It's possible for a server to have multiple associated public keys. This can happen when a Matrix server is set up on a particular domain, its key is lost, and the server continues running on the domain. Now there will be two keys associated to the domain. The old logic wouldn't fetch the new key if we already had the old key cached. The new logic will fetch any keys we don't have that we need, rather than just fetching one key per server.
Previous behavior was causing us to error out of the entire
state_cache::update_membership function when it saw an invalid m.direct,
making it impossible for affected users to join upgraded rooms. This bug
is especially bad if an affected user attempts to upgrade a room,
because we will fail to create their join event in the new room, leaving
both rooms permanently bricked.
The new behavior should never prevent users from joining a room based on
the contents of their account data, and should migrate the `m.direct`
event in a reasonable way even if it is partially corrupted by the
element bug.
This also fixes a bug where the previous implementation will
unintentionally remove any keys that aren't part of the expected
m.direct schema. I don't know of any cases where this came up in
practice.
Fixes: #46
The implementation inside each function is unchanged from the original.
I intend to clean up and fix bugs in later commits, so the diff will be
more clear.
This is supported on conduwuit, and I liked it because it's faster for
me to type than tab-completing the bot user, and because it makes it a
little easier to copy-paste admin commands.
This isn't exploitable in any way, it just meant that the bot could
receive and run commands from users who were already in the admin room
despite the bot not being in the room, which also means the bot would be
unable to send response messages.
Now, the bot will simply ignore admin room messages if the bot isn't in
the admin room.
Previously, we only fetched keys once, only requesting them again if we have any missing, allowing for ancient keys to be used to sign PDUs and transactions
Now we refresh keys that either have or are about to expire, preventing attacks that make use of leaked private keys of a homeserver
We also ensure that when validating PDUs or transactions, that they are valid at the origin_server_ts or time of us receiving the transaction respectfully
As to not break event authorization for old rooms, we need to keep old keys around
We move verify_keys which we no longer see in direct requests to the origin to old_verify_keys
We keep old_verify_keys indefinitely as mentioned above, as to not break event authorization (at least until a future MSC addresses this)
Original patch by Matthias. Benjamin just rebased it onto grapevine and
fixed clippy/rustc warnings.
Co-authored-by: Benjamin Lee <benjamin@computer.surgery>
