fix(crypto): Redecrypt non-UTD messages to remove no-longer-relevant warning shields #4644

andybalaam · 2025-02-07T14:16:21Z

I'm sorry it's a big change. I've tried to break it into decent commits, and I did a couple of preparatory PRs to make it less painful, but it's still a bit to get your head around.

The basic idea is that when a session is updated and we call retry_event_decryption, we don't only look at UTDs any more - now we also look at decrypted events, and re-request their EncryptionInfo, in case it has improved.

codecov · 2025-02-07T14:32:38Z

Codecov Report

Attention: Patch coverage is 85.22727% with 13 lines in your changes missing coverage. Please review.

Project coverage is 85.83%. Comparing base (9de6d28) to head (414f03d).

Files with missing lines	Patch %	Lines
...rates/matrix-sdk-ui/src/timeline/controller/mod.rs	85.18%	4 Missing ⚠️
crates/matrix-sdk/src/room/mod.rs	0.00%	4 Missing ⚠️
crates/matrix-sdk-ui/src/timeline/event_handler.rs	89.47%	2 Missing ⚠️
crates/matrix-sdk-ui/src/timeline/traits.rs	0.00%	2 Missing ⚠️
...tes/matrix-sdk-ui/src/timeline/controller/state.rs	95.23%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4644      +/-   ##
==========================================
+ Coverage   85.82%   85.83%   +0.01%     
==========================================
  Files         292      292              
  Lines       33761    33830      +69     
==========================================
+ Hits        28974    29037      +63     
- Misses       4787     4793       +6

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

…eItem

…imelineItem ... meaning we attempt to redecrypt them even if they are not UTDs. The redecryption doesn't actually work - that will be fixed in the next commit.

…etry decryption In later commits, we will make this cleverer, so it can calculate which non-UTD events need updating too.

Future commits will add code to try non-UTDs too, in another function.

…-UTDs Fixes element-hq/element-meta#2697

andybalaam · 2025-02-14T12:16:15Z

I swapped the Rust team reviewer to @bnjbvr since I know he has questions about including session ID in the timeline item.

richvdh

seems generally good to me. A few comments.

richvdh · 2025-02-14T13:45:12Z

crates/matrix-sdk-ui/src/timeline/traits.rs

@@ -121,6 +123,12 @@ pub(super) trait RoomDataProvider:
    ) -> impl Future<Output = Result<(), super::Error>> + SendOutsideWasm + 'a;

    fn room_info(&self) -> Subscriber<RoomInfo>;
+
+    fn get_encryption_info(


it might be "obvious" but this could use a doc-comment?

richvdh · 2025-02-14T13:46:37Z

crates/matrix-sdk-ui/src/timeline/controller/state_transaction.rs

@@ -441,6 +443,14 @@ impl<'a> TimelineStateTransaction<'a> {
        }
    }

+    pub(super) fn replace(


doc-comment?

richvdh · 2025-02-14T13:56:03Z

crates/matrix-sdk-ui/src/timeline/event_handler.rs

@@ -368,6 +368,7 @@ impl<'a, 'o> TimelineEventHandler<'a, 'o> {
        mut self,
        date_divider_adjuster: &mut DateDividerAdjuster,
        event_kind: TimelineEventKind,
+        session_id: Option<String>,


generally: I think we need a better name, or better documentation, or both, for things called session_id. It's very unclear to a casual reader what it is supposed to be.

richvdh · 2025-02-14T13:58:07Z

crates/matrix-sdk-ui/src/timeline/event_item/mod.rs

+        // In the timeline, this is used to find events that need re-decrypting but in
+        // the message preview it is not used.
+        let session_id = None;


this seems to be baking in a bit of an assumption: is there no way we can get the session id here, to guard against future changes?

If not, we should document RemoteEventTimelineItem.session_id to note that it is not always populated.

richvdh · 2025-02-14T13:58:56Z

crates/matrix-sdk-ui/src/timeline/event_item/remote.rs

+
+    /// The megolm session ID used to send this event, if it is UTD.
+    pub session_id: Option<String>,


This doesn't feel right here -- in particular the fact that it overlaps with encryption_info.

Maybe we want to replace encryption_info with an enum field. But it sounds like Benji might have bigger plans anyway.

richvdh · 2025-02-14T14:14:47Z

crates/matrix-sdk-ui/src/timeline/controller/mod.rs

+    /// `state` is the [`TimelineState`] state of the timeline.
+    /// `retry_indices` contains the indices of events to try within the
+    /// `state.items` `should_retry` checks that a session is included in
+    /// the list of updated sessions. `decryptor` does the actual work of
+    /// decrypting events.


I think there is a sort of informal convention of setting out parameter documentation as a markdown list.

richvdh · 2025-02-14T14:23:01Z

crates/matrix-sdk-ui/src/timeline/controller/mod.rs

+    let mut retry_decryption_indices = Vec::new();
+    let mut retry_info_indices = Vec::new();


I don't have a strong opinion here, but in the past I've been asked to use partition_map for this sort of thing.

We could write this as a filter followed by a partition_map?

richvdh · 2025-02-14T14:24:03Z

crates/matrix-sdk-ui/src/timeline/controller/mod.rs

-        // Retry decrypting
-        self.retry_event_decryption_by_index(state, retry_indices, should_retry, decryptor).await;
+        // Retry decrypting UTDs
+        let state = self.state.clone().write_owned().await;


feels like this state.clone() should happen inside retry_event_decryption_by_index

richvdh · 2025-02-14T14:25:42Z

crates/matrix-sdk-ui/src/timeline/controller/state.rs

@@ -225,6 +228,45 @@ impl TimelineState {
        txn.commit();
    }

+    /// Try to fetch [`EncryptionInfo`] for the events with the supplied
+    /// indices, and update them where we succeed.
+    pub(super) async fn retry_event_encryption_info<P: RoomDataProvider>(


I have to say that having this here but retry_event_decryption_by_index in the other place feels rather asymmetric. Is there a reason they need to be different?

andybalaam changed the title ~~refactor(crypto): Store the session ID of a UTD in RemoteEventTimelineItem~~ fix(crypto): Redecrypt non-UTD messages to remove no-longer-relevant warning shields Feb 7, 2025

andybalaam force-pushed the andybalaam/redecrypt-non-utds branch from 9a19fcf to 9cbfbfb Compare February 7, 2025 14:17

andybalaam force-pushed the andybalaam/redecrypt-non-utds branch 3 times, most recently from 741aa40 to d83e187 Compare February 14, 2025 11:45

andybalaam added 7 commits February 14, 2025 11:59

tool(ui): Allow getting encryption info via a Room instance

aa64150

tool(ui): Provide a replace method for TimelineStateTransaction

8d0fd62

refactor(crypto): Store the session ID of a UTD in RemoteEventTimelin…

45ddbf1

…eItem

refactor(crypto): Store session ID in EncryptionInfo and provide to T…

5cc10ba

…imelineItem ... meaning we attempt to redecrypt them even if they are not UTDs. The redecryption doesn't actually work - that will be fixed in the next commit.

refactor(timeline): Extract a function to calculate which events to r…

dca6881

…etry decryption In later commits, we will make this cleverer, so it can calculate which non-UTD events need updating too.

refactor(timeline): Extract a function for retrying decryption

ff1dde9

Future commits will add code to try non-UTDs too, in another function.

fix(crypto): When a session updates, re-fetch encryption info for non…

414f03d

…-UTDs Fixes element-hq/element-meta#2697

andybalaam force-pushed the andybalaam/redecrypt-non-utds branch from d83e187 to 414f03d Compare February 14, 2025 11:59

andybalaam marked this pull request as ready for review February 14, 2025 12:11

andybalaam requested review from a team as code owners February 14, 2025 12:11

andybalaam requested review from stefanceriu, richvdh and bnjbvr and removed request for a team and stefanceriu February 14, 2025 12:11

richvdh reviewed Feb 14, 2025

View reviewed changes

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

fix(crypto): Redecrypt non-UTD messages to remove no-longer-relevant warning shields #4644

fix(crypto): Redecrypt non-UTD messages to remove no-longer-relevant warning shields #4644

andybalaam commented Feb 7, 2025 •

edited

Loading

codecov bot commented Feb 7, 2025 •

edited

Loading

andybalaam commented Feb 14, 2025

richvdh left a comment

richvdh Feb 14, 2025

richvdh Feb 14, 2025

richvdh Feb 14, 2025

richvdh Feb 14, 2025

richvdh Feb 14, 2025

richvdh Feb 14, 2025

richvdh Feb 14, 2025

richvdh Feb 14, 2025

richvdh Feb 14, 2025


		/// The megolm session ID used to send this event, if it is UTD.
		pub session_id: Option<String>,

		let mut retry_decryption_indices = Vec::new();
		let mut retry_info_indices = Vec::new();

fix(crypto): Redecrypt non-UTD messages to remove no-longer-relevant warning shields #4644

Are you sure you want to change the base?

fix(crypto): Redecrypt non-UTD messages to remove no-longer-relevant warning shields #4644

Conversation

andybalaam commented Feb 7, 2025 • edited Loading

codecov bot commented Feb 7, 2025 • edited Loading

Codecov Report

andybalaam commented Feb 14, 2025

richvdh left a comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

andybalaam commented Feb 7, 2025 •

edited

Loading

codecov bot commented Feb 7, 2025 •

edited

Loading