Refactor and convert `Linearizer` to async. This makes a `Linearizer`
cancellation bug easier to fix.
Also refactor to use an async context manager, which eliminates an
unlikely footgun where code that doesn't immediately use the context
manager could forget to release the lock.
Signed-off-by: Sean Quah <seanq@element.io>
Since the object it returns is a ReplicationCommandHandler.
This is clean-up from adding support to Redis where the command handler
was added as an additional layer of abstraction from the TCP protocol.
...and various code supporting it.
The /spaces endpoint was from an old version of MSC2946 and included
both a Client-Server and Server-Server API. Note that the unstable
/hierarchy endpoint (from the final version of MSC2946) is not yet
removed.
Before this fix, a legitimate 404 from a federation endpoint (e.g. due
to an unknown room) would be treated as an unknown endpoint. This
could cause unnecessary federation traffic.
This is an endpoint that we have server-side support for, but no client-side support. It's going to be useful for resyncing partial-stated rooms, so let's introduce it.
* Make `get_auth_chain_ids` return a Set
It has a set internally, and a set is often useful where it gets used, so let's
avoid converting to an intermediate list.
* Minor refactors in `on_send_join_request`
A little bit of non-functional groundwork
* Implement MSC3706: partial state in /send_join response
The idea here is to set the parent span for incoming federation requests to the
*outgoing* span on the other end. That means that you can see (most of) the
full end-to-end flow when you have a process that includes federation requests.
However, in order not to lose information, we still want a link to the
`incoming-federation-request` span from the servlet, so we have to create
another span to do exactly that.
* Fix losing incoming EDUs if debug logging enabled
Fixes#11889. Homeservers should only be affected if the
`synapse.8631_debug` logger was enabled for DEBUG mode.
I am not sure if this merits a bugfix release: I think the logging can
be disabled in config if anyone is affected? But it is still pretty bad.
Debug for #8631.
I'm having a hard time tracking down what's going wrong in that issue.
In the reported example, I could see server A sending federation traffic
to server B and all was well. Yet B reports out-of-sync device updates
from A.
I couldn't see what was _in_ the events being sent from A to B. So I
have added some crude logging to track
- when we have updates to send to a remote HS
- the edus we actually accumulate to send
- when a federation transaction includes a device list update edu
- when such an EDU is received
This is a bit of a sledgehammer.
I've never found this terribly useful. I think it was added in the early days
of Synapse, without much thought as to what would actually be useful to log,
and has just been cargo-culted ever since.
Rather, it tends to clutter up debug logs with useless information.
* `_auth_and_persist_outliers`: mark persisted events as outliers
Mark any events that get persisted via `_auth_and_persist_outliers` as, well,
outliers.
Currently this will be a no-op as everything will already be flagged as an
outlier, but I'm going to change that.
* `process_remote_join`: stop flagging as outlier
The events are now flagged as outliers later on, by `_auth_and_persist_outliers`.
* `send_join`: remove `outlier=True`
The events created here are returned in the result of `send_join` to
`FederationHandler.do_invite_join`. From there they are passed into
`FederationEventHandler.process_remote_join`, which passes them to
`_auth_and_persist_outliers`... which sets the `outlier` flag.
* `get_event_auth`: remove `outlier=True`
stop flagging the events returned by `get_event_auth` as outliers. This method
is only called by `_get_remote_auth_chain_for_event`, which passes the results
into `_auth_and_persist_outliers`, which will flag them as outliers.
* `_get_remote_auth_chain_for_event`: remove `outlier=True`
we pass all the events into `_auth_and_persist_outliers`, which will now flag
the events as outliers.
* `_check_sigs_and_hash_and_fetch`: remove unused `outlier` parameter
This param is now never set to True, so we can remove it.
* `_check_sigs_and_hash_and_fetch_one`: remove unused `outlier` param
This is no longer set anywhere, so we can remove it.
* `get_pdu`: remove unused `outlier` parameter
... and chase it down into `get_pdu_from_destination_raw`.
* `event_from_pdu_json`: remove redundant `outlier` param
This is never set to `True`, so can be removed.
* changelog
* update docstring
Events returned by `backfill` should not be flagged as outliers.
Fixes:
```
AssertionError: null
File "synapse/handlers/federation.py", line 313, in try_backfill
dom, room_id, limit=100, extremities=extremities
File "synapse/handlers/federation_event.py", line 517, in backfill
await self._process_pulled_events(dest, events, backfilled=True)
File "synapse/handlers/federation_event.py", line 642, in _process_pulled_events
await self._process_pulled_event(origin, ev, backfilled=backfilled)
File "synapse/handlers/federation_event.py", line 669, in _process_pulled_event
assert not event.internal_metadata.is_outlier()
```
See https://sentry.matrix.org/sentry/synapse-matrixorg/issues/231992Fixes#8894.
* remove `start_active_span_from_request`
Instead, pull out a separate function, `span_context_from_request`, to extract
the parent span, which we can then pass into `start_active_span` as
normal. This seems to be clearer all round.
* Remove redundant tags from `incoming-federation-request`
These are all wrapped up inside a parent span generated in AsyncResource, so
there's no point duplicating all the tags that are set there.
* Leave request spans open until the request completes
It may take some time for the response to be encoded into JSON, and that JSON
to be streamed back to the client, and really we want that inside the top-level
span, so let's hand responsibility for closure to the SynapseRequest.
* opentracing logs for HTTP request events
* changelog
MSC3030: https://github.com/matrix-org/matrix-doc/pull/3030
Client API endpoint. This will also go and fetch from the federation API endpoint if unable to find an event locally or we found an extremity with possibly a closer event we don't know about.
```
GET /_matrix/client/unstable/org.matrix.msc3030/rooms/<roomID>/timestamp_to_event?ts=<timestamp>&dir=<direction>
{
"event_id": ...
"origin_server_ts": ...
}
```
Federation API endpoint:
```
GET /_matrix/federation/unstable/org.matrix.msc3030/timestamp_to_event/<roomID>?ts=<timestamp>&dir=<direction>
{
"event_id": ...
"origin_server_ts": ...
}
```
Co-authored-by: Erik Johnston <erik@matrix.org>
* Make lock better handle process being killed
If the process gets killed and restarted (so that it didn't have a
chance to drop its locks gracefully) then there may still be locks in
the DB that are for the same instance that haven't yet timed out but are
safe to delete.
We handle this case by a) checking if the current instance already has
taken out the lock, and b) if not then ignoring locks that are for the
same instance.
* Periodically check for old staged events
This is to protect against other instances dying and their locks timing
out.
This fixes a "Event not signed by authorising server" error when
transition room member from join -> join, e.g. when updating a
display name or avatar URL for restricted rooms.
* Factor more stuff out of `_get_events_and_persist`
It turns out that the event-sorting algorithm in `_get_events_and_persist` is
also useful in other circumstances. Here we move the current
`_auth_and_persist_fetched_events` to `_auth_and_persist_fetched_events_inner`,
and then factor the sorting part out to `_auth_and_persist_fetched_events`.
* `_get_remote_auth_chain_for_event`: remove redundant `outlier` assignment
`get_event_auth` returns events with the outlier flag already set, so this is
redundant (though we need to update a test where `get_event_auth` is mocked).
* `_get_remote_auth_chain_for_event`: move existing-event tests earlier
Move a couple of tests outside the loop. This is a bit inefficient for now, but
a future commit will make it better. It should be functionally identical.
* `_get_remote_auth_chain_for_event`: use `_auth_and_persist_fetched_events`
We can use the same codepath for persisting the events fetched as part of an
auth chain as for those fetched individually by `_get_events_and_persist` for
building the state at a backwards extremity.
* `_get_remote_auth_chain_for_event`: use a dict for efficiency
`_auth_and_persist_fetched_events` sorts the events itself, so we no longer
need to care about maintaining the ordering from `get_event_auth` (and no
longer need to sort by depth in `get_event_auth`).
That means that we can use a map, making it easier to filter out events we
already have, etc.
* changelog
* `_auth_and_persist_fetched_events`: improve docstring
Here we split on_receive_pdu into two functions (on_receive_pdu and process_pulled_event), rather than having both cases in the same method. There's a tiny bit of overlap, but not that much.
If the new /hierarchy API does not exist on all destinations,
fallback to querying the /spaces API and translating the results.
This is a backwards compatibility hack since not all of the
federated homeservers will update at the same time.
* Include outlier status in `str(event)`
In places where we log event objects, knowing whether or not you're dealing
with an outlier is super useful.
* Remove duplicated logging in get_missing_events
When we process events received from get_missing_events, we log them twice
(once in `_get_missing_events_for_pdu`, and once in `on_receive_pdu`). Reduce
the duplication by removing the logging in `on_receive_pdu`, and ensuring the
call sites do sensible logging.
* log in `on_receive_pdu` when we already have the event
* Log which prev_events we are missing
* changelog
Instead of wrapping the JSON into an object, this creates concrete
instances for Transaction and Edu. This allows for improved type
hints and simplified code.
If the federation client receives an M_UNABLE_TO_AUTHORISE_JOIN or
M_UNABLE_TO_GRANT_JOIN response it will attempt another server
before giving up completely.
Improves type hints for:
* parse_{boolean,integer}
* parse_{boolean,integer}_from_args
* parse_json_{value,object}_from_request
And fixes any incorrect calls that resulted from unknown types.
This is to help with performance, where trying to connect to thousands
of hosts at once can consume a lot of CPU (due to TLS etc).
Co-authored-by: Brendan Abolivier <babolivier@matrix.org>
Fixes#9490
This will break a couple of SyTest that are expecting failures to be added to the response of a federation /send, which obviously doesn't happen now that things are asynchronous.
Two drawbacks:
Currently there is no logic to handle any events left in the staging area after restart, and so they'll only be handled on the next incoming event in that room. That can be fixed separately.
We now only process one event per room at a time. This can be fixed up further down the line.
The idea here is to stop people sending things that aren't joins/leaves/knocks through these endpoints: previously you could send anything you liked through them. I wasn't able to find any security holes from doing so, but it doesn't sound like a good thing.
* Room version 7 for knocking.
* Stable prefixes and endpoints (both client and federation) for knocking.
* Removes the experimental configuration flag.
==============================
Bugfixes
--------
- Fix a bug introduced in v1.35.0rc1 when calling the spaces summary API via a GET request. ([\#10079](https://github.com/matrix-org/synapse/issues/10079))
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Merge tag 'v1.35.0rc2' into develop
Synapse 1.35.0rc2 (2021-05-27)
==============================
Bugfixes
--------
- Fix a bug introduced in v1.35.0rc1 when calling the spaces summary API via a GET request. ([\#10079](https://github.com/matrix-org/synapse/issues/10079))
Also add support for giving a callback to generate the JSON object to
verify. This should reduce memory usage, as we no longer have the event
in memory in dict form (which has a large memory footprint) for extend
periods of time.
Instead of parsing the full response to `/send_join` into Python objects (which can be huge for large rooms) and *then* parsing that into events, we instead use ijson to stream parse the response directly into `EventBase` objects.
Per changes in MSC2946, the C-S and S-S APIs for spaces summary
should use GET requests.
Until this is stable, the POST endpoints still exist.
This does not switch federation requests to use the GET version yet
since it is newly added and already deployed servers might not support
it. When switching to the stable endpoint we should switch to GET
requests.
This ensures that something like an auth error (403) will be
returned to the requester instead of attempting to try more
servers, which will likely result in the same error, and then
passing back a generic 400 error.
This basically speeds up federation by "squeezing" each individual dual database call (to destinations and destination_rooms), which previously happened per every event, into one call for an entire batch (100 max).
Signed-off-by: Jonathan de Jong <jonathan@automatia.nl>
Part of #9744
Removes all redundant `# -*- coding: utf-8 -*-` lines from files, as python 3 automatically reads source code as utf-8 now.
`Signed-off-by: Jonathan de Jong <jonathan@automatia.nl>`
We pull all destinations requiring catchup from the DB in batches.
However, if all those destinations get filtered out (due to the
federation sender being sharded), then the `last_processed` destination
doesn't get updated, and we keep requesting the same set repeatedly.
At the moment, if you'd like to share presence between local or remote users, those users must be sharing a room together. This isn't always the most convenient or useful situation though.
This PR adds a module to Synapse that will allow deployments to set up extra logic on where presence updates should be routed. The module must implement two methods, `get_users_for_states` and `get_interested_users`. These methods are given presence updates or user IDs and must return information that Synapse will use to grant passing presence updates around.
A method is additionally added to `ModuleApi` which allows triggering a set of users to receive the current, online presence information for all users they are considered interested in. This is the equivalent of that user receiving presence information during an initial sync.
The goal of this module is to be fairly generic and useful for a variety of applications, with hard requirements being:
* Sending state for a specific set or all known users to a defined set of local and remote users.
* The ability to trigger an initial sync for specific users, so they receive all current state.
This should fix a class of bug where we forget to check if e.g. the appservice shouldn't be ratelimited.
We also check the `ratelimit_override` table to check if the user has ratelimiting disabled. That table is really only meant to override the event sender ratelimiting, so we don't use any values from it (as they might not make sense for different rate limits), but we do infer that if ratelimiting is disabled for the user we should disabled all ratelimits.
Fixes#9663
Builds on the work done in #9643 to add a federation API for space summaries.
There's a bit of refactoring of the existing client-server code first, to avoid too much duplication.
Currently federation catchup will send the last *local* event that we
failed to send to the remote. This can cause issues for large rooms
where lots of servers have sent events while the remote server was down,
as when it comes back up again it'll be flooded with events from various
points in the DAG.
Instead, let's make it so that all the servers send the most recent
events, even if its not theirs. The remote should deduplicate the
events, so there shouldn't be much overhead in doing this.
Alternatively, the servers could only send local events if they were
also extremities and hope that the other server will send the event
over, but that is a bit risky.
Federation catch up mode is very inefficient if the number of events
that the remote server has missed is small, since handling gaps can be
very expensive, c.f. #9492.
Instead of going into catch up mode whenever we see an error, we instead
do so only if we've backed off from trying the remote for more than an
hour (the assumption being that in such a case it is more than a
transient failure).
This PR attempts to eliminate unnecessary presence sending work when your local server joins a room, or when a remote server joins a room your server is participating in by processing state deltas in chunks rather than individually.
---
When your server joins a room for the first time, it requests the historical state as well. This chunk of new state is passed to the presence handler which, after filtering that state down to only membership joins, will send presence updates to homeservers for each join processed.
It turns out that we were being a bit naive and processing each event individually, and sending out presence updates for every one of those joins. Even if many different joins were users on the same server (hello IRC bridges), we'd send presence to that same homeserver for every remote user join we saw.
This PR attempts to deduplicate all of that by processing the entire batch of state deltas at once, instead of only doing each join individually. We process the joins and note down which servers need which presence:
* If it was a local user join, send that user's latest presence to all servers in the room
* If it was a remote user join, send the presence for all local users in the room to that homeserver
We deduplicate by inserting all of those pending updates into a dictionary of the form:
```
{
server_name1: {presence_update1, ...},
server_name2: {presence_update1, presence_update2, ...}
}
```
Only after building this dict do we then start sending out presence updates.
Add off-by-default configuration settings to:
- disable putting an invitee's profile info in invite events
- disable profile lookup via federation
Signed-off-by: Andrew Ferrazzutti <fair@miscworks.net>
- Update black version to the latest
- Run black auto formatting over the codebase
- Run autoformatting according to [`docs/code_style.md
`](80d6dc9783/docs/code_style.md)
- Update `code_style.md` docs around installing black to use the correct version
Replaces the `federation_ip_range_blacklist` configuration setting with an
`ip_range_blacklist` setting with wider scope. It now applies to:
* Federation
* Identity servers
* Push notifications
* Checking key validitity for third-party invite events
The old `federation_ip_range_blacklist` setting is still honored if present, but
with reduced scope (it only applies to federation and identity servers).
* Consistently use room_id from federation request body
Some federation APIs have a redundant `room_id` path param (see
https://github.com/matrix-org/matrix-doc/issues/2330). We should make sure we
consistently use either the path param or the body param, and the body param is
easier.
* Kill off some references to "context"
Once upon a time, "rooms" were known as "contexts". I think this kills of the
last references to "contexts".
We do it this way round so that only the "owner" can delete the access token (i.e. `/logout/all` by the "owner" also deletes that token, but `/logout/all` by the "target user" doesn't).
A future PR will add an API for creating such a token.
When the target user and authenticated entity are different the `Processed request` log line will be logged with a: `{@admin:server as @bob:server} ...`. I'm not convinced by that format (especially since it adds spaces in there, making it harder to use `cut -d ' '` to chop off the start of log lines). Suggestions welcome.
* Fix outbound federaion with multiple event persisters.
We incorrectly notified federation senders that the minimum persisted
stream position had advanced when we got an `RDATA` from an event
persister.
Notifying of federation senders already correctly happens in the
notifier, so we just delete the offending line.
* Change some interfaces to use RoomStreamToken.
By enforcing use of `RoomStreamTokens` we make it less likely that
people pass in random ints that they got from somewhere random.
There's no need for it to be in the dict as well as the events table. Instead,
we store it in a separate attribute in the EventInternalMetadata object, and
populate that on load.
This means that we can rely on it being correctly populated for any event which
has been persited to the database.
==============================
In addition to the below, Synapse 1.20.0rc5 also includes the bug fix that was included in 1.19.3.
Features
--------
- Add flags to the `/versions` endpoint for whether new rooms default to using E2EE. ([\#8343](https://github.com/matrix-org/synapse/issues/8343))
Bugfixes
--------
- Fix rate limiting of federation `/send` requests. ([\#8342](https://github.com/matrix-org/synapse/issues/8342))
- Fix a longstanding bug where back pagination over federation could get stuck if it failed to handle a received event. ([\#8349](https://github.com/matrix-org/synapse/issues/8349))
Internal Changes
----------------
- Blacklist [MSC2753](https://github.com/matrix-org/matrix-doc/pull/2753) SyTests until it is implemented. ([\#8285](https://github.com/matrix-org/synapse/issues/8285))
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Merge tag 'v1.20.0rc5' into develop
Synapse 1.20.0rc5 (2020-09-18)
==============================
In addition to the below, Synapse 1.20.0rc5 also includes the bug fix that was included in 1.19.3.
Features
--------
- Add flags to the `/versions` endpoint for whether new rooms default to using E2EE. ([\#8343](https://github.com/matrix-org/synapse/issues/8343))
Bugfixes
--------
- Fix rate limiting of federation `/send` requests. ([\#8342](https://github.com/matrix-org/synapse/issues/8342))
- Fix a longstanding bug where back pagination over federation could get stuck if it failed to handle a received event. ([\#8349](https://github.com/matrix-org/synapse/issues/8349))
Internal Changes
----------------
- Blacklist [MSC2753](https://github.com/matrix-org/matrix-doc/pull/2753) SyTests until it is implemented. ([\#8285](https://github.com/matrix-org/synapse/issues/8285))
Synapse 1.19.3 (2020-09-18)
===========================
Bugfixes
--------
- Partially mitigate bug where newly joined servers couldn't get past
events in a room when there is a malformed event.
([\#8350](https://github.com/matrix-org/synapse/issues/8350))
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Merge tag 'v1.19.3' into release-v1.20.0
1.19.3
Synapse 1.19.3 (2020-09-18)
===========================
Bugfixes
--------
- Partially mitigate bug where newly joined servers couldn't get past
events in a room when there is a malformed event.
([\#8350](https://github.com/matrix-org/synapse/issues/8350))
Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>
Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>
* Fix _set_destination_retry_timings
This came about because the code assumed that retry_interval
could not be NULL — which has been challenged by catch-up.
This is a bit of a hack, as `_check_sigs_and_hash_and_fetch` is intended
for attempting to pull an event from the database/(re)pull it from the
server that originally sent the event if checking the signature of the
event fails.
During backfill we *know* that we won't have the event in our database,
however it is still useful to be able to query the original sending
server as the server we're backfilling from may be acting maliciously.
The main benefit and reason for this change however is that
`_check_sigs_and_hash_and_fetch` will drop an event during backfill if
it cannot be successfully validated, whereas the current code will
simply fail the backfill request - resulting in the client's /messages
request silently being dropped.
This is a quick patch to fix backfilling rooms that contain malformed
events. A better implementation in planned in future.
If we send out an event which refers to `prev_events` which other servers in
the federation are missing, then (after a round or two of backfill attempts),
they will end up asking us for `/state_ids` at a particular point in the DAG.
As per https://github.com/matrix-org/synapse/issues/7893, this is quite
expensive, and we tend to see lots of very similar requests around the same
time.
We can therefore handle this much more efficiently by using a cache, which (a)
ensures that if we see the same request from multiple servers (or even the same
server, multiple times), then they share the result, and (b) any other servers
that miss the initial excitement can also benefit from the work.
[It's interesting to note that `/state` has a cache for exactly this
reason. `/state` is now essentially unused and replaced with `/state_ids`, but
evidently when we replaced it we forgot to add a cache to the new endpoint.]
For inbound federation requests, if a given remote server makes too many
requests at once, we start stacking them up rather than processing them
immediatedly.
However, that means that there is a fair chance that the requesting server will
disconnect before we start processing the request. In that case, if it was a
read-only request (ie, a GET request), there is absolutely no point in
building a response (and some requests are quite expensive to handle).
Even in the case of a POST request, one of two things will happen:
* Most likely, the requesting server will retry the request and we'll get the
information anyway.
* Even if it doesn't, the requesting server has to assume that we didn't get
the memo, and act accordingly.
In short, we're better off aborting the request at this point rather than
ploughing on with what might be a quite expensive request.
It was correct at the time of our friend Jorik writing it (checking
git blame), but the world has moved now and it is no longer a
generator.
Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>
