Commit Graph

9 Commits

Author SHA1 Message Date
Eric Eastwood
40bb37eb27
Stop getting missing prev_events after we already know their signature is invalid (#13816)
While https://github.com/matrix-org/synapse/pull/13635 stops us from doing the slow thing after we've already done it once, this PR stops us from doing one of the slow things in the first place.

Related to
 - https://github.com/matrix-org/synapse/issues/13622
    - https://github.com/matrix-org/synapse/pull/13635
 - https://github.com/matrix-org/synapse/issues/13676

Part of https://github.com/matrix-org/synapse/issues/13356

Follow-up to https://github.com/matrix-org/synapse/pull/13815 which tracks event signature failures.

With this PR, we avoid the call to the costly `_get_state_ids_after_missing_prev_event` because the signature failure will count as an attempt before and we filter events based on the backoff before calling `_get_state_ids_after_missing_prev_event` now.

For example, this will save us 156s out of the 185s total that this `matrix.org` `/messages` request. If you want to see the full Jaeger trace of this, you can drag and drop this `trace.json` into your own Jaeger, https://gist.github.com/MadLittleMods/4b12d0d0afe88c2f65ffcc907306b761

To explain this exact scenario around `/messages` -> backfill, we call `/backfill` and first check the signatures of the 100 events. We see bad signature for `$luA4l7QHhf_jadH3mI-AyFqho0U2Q-IXXUbGSMq6h6M` and `$zuOn2Rd2vsC7SUia3Hp3r6JSkSFKcc5j3QTTqW_0jDw` (both member events). Then we process the 98 events remaining that have valid signatures but one of the events references `$luA4l7QHhf_jadH3mI-AyFqho0U2Q-IXXUbGSMq6h6M` as a `prev_event`. So we have to do the whole `_get_state_ids_after_missing_prev_event` rigmarole which pulls in those same events which fail again because the signatures are still invalid.

 - `backfill`
    - `outgoing-federation-request` `/backfill`
    - `_check_sigs_and_hash_and_fetch`
       - `_check_sigs_and_hash_and_fetch_one` for each event received over backfill
          -  `$luA4l7QHhf_jadH3mI-AyFqho0U2Q-IXXUbGSMq6h6M` fails with `Signature on retrieved event was invalid.`: `unable to verify signature for sender domain xxx: 401: Failed to find any key to satisfy: _FetchKeyRequest(...)`
          -  `$zuOn2Rd2vsC7SUia3Hp3r6JSkSFKcc5j3QTTqW_0jDw` fails with `Signature on retrieved event was invalid.`: `unable to verify signature for sender domain xxx: 401: Failed to find any key to satisfy: _FetchKeyRequest(...)`
   - `_process_pulled_events`
      - `_process_pulled_event` for each validated event
         -  Event `$Q0iMdqtz3IJYfZQU2Xk2WjB5NDF8Gg8cFSYYyKQgKJ0` references `$luA4l7QHhf_jadH3mI-AyFqho0U2Q-IXXUbGSMq6h6M` as a `prev_event` which is missing so we try to get it
            - `_get_state_ids_after_missing_prev_event`
               - `outgoing-federation-request` `/state_ids`
               -  `get_pdu` for `$luA4l7QHhf_jadH3mI-AyFqho0U2Q-IXXUbGSMq6h6M` which fails the signature check again
               -  `get_pdu` for `$zuOn2Rd2vsC7SUia3Hp3r6JSkSFKcc5j3QTTqW_0jDw` which fails the signature check
2022-10-15 00:36:49 -05:00
Sean Quah
b73cbb8215
Avoid putting rejected events in room state (#13723)
Signed-off-by: Sean Quah <seanq@matrix.org>
2022-09-16 12:45:04 +01:00
Eric Eastwood
957e3d74fc
Keep track when we try and fail to process a pulled event (#13589)
We can follow-up this PR with:

 1. Only try to backfill from an event if we haven't tried recently -> https://github.com/matrix-org/synapse/issues/13622
 1. When we decide to backfill that event again, process it in the background so it doesn't block and make `/messages` slow when we know it will probably fail again -> https://github.com/matrix-org/synapse/issues/13623
 1. Generally track failures everywhere we try and fail to pull an event over federation -> https://github.com/matrix-org/synapse/issues/13700

Fix https://github.com/matrix-org/synapse/issues/13621

Part of https://github.com/matrix-org/synapse/issues/13356

Mentioned in [internal doc](https://docs.google.com/document/d/1lvUoVfYUiy6UaHB6Rb4HicjaJAU40-APue9Q4vzuW3c/edit#bookmark=id.qv7cj51sv9i5)
2022-09-14 13:57:50 -05:00
David Robertson
52a0c8f2f7
Rename test case method to add_hashes_and_signatures_from_other_server (#13255) 2022-07-12 18:46:32 +00:00
Richard van der Hoff
d4b1c0d800
Fix inconsistencies in event validation (#13088) 2022-06-17 16:30:59 +01:00
Erik Johnston
888a29f412
Wait for lazy join to complete when getting current state (#12872) 2022-06-01 16:02:53 +01:00
Erik Johnston
1e453053cb
Rename storage classes (#12913) 2022-05-31 12:17:50 +00:00
Erik Johnston
c72d26c1e1
Refactor EventContext (#12689)
Refactor how the `EventContext` class works, with the intention of reducing the amount of state we fetch from the DB during event processing.

The idea here is to get rid of the cached `current_state_ids` and `prev_state_ids` that live in the `EventContext`, and instead defer straight to the database (and its caching). 

One change that may have a noticeable effect is that we now no longer prefill the `get_current_state_ids` cache on a state change. However, that query is relatively light, since its just a case of reading a table from the DB (unlike fetching state at an event which is more heavyweight). For deployments with workers this cache isn't even used.


Part of #12684
2022-05-10 19:43:13 +00:00
Richard van der Hoff
9b43df1f7b
Optimise _get_state_after_missing_prev_event: use /state (#12040)
If we're missing most of the events in the room state, then we may as well call the /state endpoint, instead of individually requesting each and every event.
2022-04-01 12:53:42 +01:00