fix(crypto): Store session ID in EncryptionInfo, and use it to redecrypt items even if they are not UTDs.

Author: andybalaam

crates/matrix-sdk-base/src/event_cache/store/integration_tests.rs

@@ -51,6 +51,7 @@ pub fn make_test_event(room_id: &RoomId, content: &str) -> TimelineEvent {
             sender_claimed_keys: Default::default(),
         },
         verification_state: VerificationState::Verified,
+        session_id: "mysessionid9".to_owned(),
     };
 
     let event = EventFactory::new()

crates/matrix-sdk-common/src/deserialized_responses.rs

@@ -302,6 +302,9 @@ pub struct EncryptionInfo {
     /// Callers that persist this should mark the state as dirty when a device
     /// change is received down the sync.
     pub verification_state: VerificationState,
+    /// The Megolm session ID that was used to encrypt this event.
+    #[serde(default)]
+    pub session_id: String,
 }
 
 /// Represents a matrix room event that has been returned from `/sync`,
@@ -541,10 +544,13 @@ impl TimelineEventKind {
         }
     }
 
-    /// The Megolm session ID that was used to send this event, if it is a UTD.
+    /// The Megolm session ID that was used to send this event, if it was
+    /// encrypted.
     pub fn session_id(&self) -> Option<String> {
         match self {
-            TimelineEventKind::Decrypted(_decrypted_room_event) => None,
+            TimelineEventKind::Decrypted(decrypted_room_event) => {
+                Some(decrypted_room_event.encryption_info.session_id.clone())
+            }
             TimelineEventKind::UnableToDecrypt { utd_info, .. } => utd_info.session_id.clone(),
             TimelineEventKind::PlainText { .. } => None,
         }
@@ -1051,6 +1057,7 @@ mod tests {
                         sender_claimed_keys: Default::default(),
                     },
                     verification_state: VerificationState::Verified,
+                    session_id: "xyz".to_owned(),
                 },
                 unsigned_encryption_info: Some(BTreeMap::from([(
                     UnsignedEventLocation::RelationsReplace,
@@ -1089,6 +1096,7 @@ mod tests {
                                 }
                             },
                             "verification_state": "Verified",
+                            "session_id": "xyz",
                         },
                         "unsigned_encryption_info": {
                             "RelationsReplace": {"UnableToDecrypt": {
@@ -1137,6 +1145,7 @@ mod tests {
             event.encryption_info().unwrap().algorithm_info,
             AlgorithmInfo::MegolmV1AesSha2 { .. }
         );
+        assert_eq!(event.encryption_info().unwrap().session_id, "");
 
         // Test that the previous format, with an undecryptable unsigned event, can also
         // be deserialized.
@@ -1363,6 +1372,7 @@ mod tests {
                 sender_claimed_keys: Default::default(),
             },
             verification_state: VerificationState::Verified,
+            session_id: "mysessionid76".to_owned(),
         };
 
         with_settings!({sort_maps =>true}, {
@@ -1392,6 +1402,7 @@ mod tests {
                         ]),
                     },
                     verification_state: VerificationState::Verified,
+                    session_id: "mysessionid112".to_owned(),
                 },
                 unsigned_encryption_info: Some(BTreeMap::from([(
                     UnsignedEventLocation::RelationsThreadLatestEvent,

crates/matrix-sdk-common/src/snapshots/matrix_sdk_common__deserialized_responses__tests__snapshot_test_encryption_info.snap

@@ -11,5 +11,6 @@ expression: info
       "sender_claimed_keys": {}
     }
   },
-  "verification_state": "Verified"
+  "verification_state": "Verified",
+  "session_id": "mysessionid76"
 }

crates/matrix-sdk-common/src/snapshots/matrix_sdk_common__deserialized_responses__tests__snapshot_test_sync_timeline_event.snap

@@ -17,6 +17,7 @@ expression: "serde_json::to_value(&room_event).unwrap()"
         },
         "sender": "@sender:example.com",
         "sender_device": "ABCDEFGHIJ",
+        "session_id": "mysessionid112",
         "verification_state": "Verified"
       },
       "event": {

crates/matrix-sdk-crypto/src/machine/mod.rs

@@ -1678,6 +1678,7 @@ impl OlmMachine {
                     .collect(),
             },
             verification_state,
+            session_id: session.session_id().to_owned(),
         })
     }
 

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

@@ -66,7 +66,7 @@ pub(in crate::timeline) struct RemoteEventTimelineItem {
     /// Where we got this event from: A sync response or pagination.
     pub origin: RemoteEventOrigin,
 
-    /// The megolm session ID used to send this event, if it is UTD.
+    /// The megolm session ID used to send this event, if it was encrypted.
     pub session_id: Option<String>,
 }
 

crates/matrix-sdk-ui/src/timeline/tests/edit.rs

@@ -176,6 +176,7 @@ async fn test_edit_updates_encryption_info() {
             sender_claimed_keys: BTreeMap::new(),
         },
         verification_state: VerificationState::Verified,
+        session_id: "mysessionid6333".to_owned(),
     };
 
     let original_event: TimelineEvent = DecryptedRoomEvent {