feat: Append withheld info from room key bundle to store.

crates/matrix-sdk-crypto/CHANGELOG.md

@@ -6,6 +6,16 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased] - ReleaseDate
 
+### Features
+
+- Improves feedback support for shared history when downloading room key bundles.
+  ([#5737](https://github.com/matrix-org/matrix-rust-sdk/pull/5737))
+  - Add `RoomKeyWithheldEntry` enum, wrapping either a received to-device `m.room_key.withheld` event or
+    its content, if derived from a downloaded room key bundle.
+  - `OlmMachine::receive_room_key_bundle` now appends withheld key information to the store.
+  - [**breaking**] `Changes::withheld_session_info` now stores a `RookKeyWithheldEntry` in each `room-id`-`session-id` entry.
+  - [**breaking**] `CryptoStore::get_withheld_info` now returns `Result<Option<RookKeyWithheldEntry>>`. This change also affects `MemoryStore`.
+
 ### Bug Fixes
 
 - Fix a bug introduced in 0.14.0 which meant that the serialization of the value returned by `OtherUserIdentity::verification_request_content` did not include a `msgtype` field.

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

@@ -1003,14 +1003,16 @@ impl OlmMachine {
 
         if let RoomKeyWithheldContent::MegolmV1AesSha2(
             MegolmV1AesSha2WithheldContent::BlackListed(c)
-            | MegolmV1AesSha2WithheldContent::Unverified(c),
+            | MegolmV1AesSha2WithheldContent::Unverified(c)
+            | MegolmV1AesSha2WithheldContent::Unauthorised(c)
+            | MegolmV1AesSha2WithheldContent::Unavailable(c),
         ) = &event.content
         {
             changes
                 .withheld_session_info
                 .entry(c.room_id.to_owned())
                 .or_default()
-                .insert(c.session_id.to_owned(), event.to_owned());
+                .insert(c.session_id.to_owned(), event.to_owned().into());
         }
     }
 

crates/matrix-sdk-crypto/src/store/integration_tests.rs

@@ -53,7 +53,8 @@ macro_rules! cryptostore_integration_tests {
                 store::{
                     types::{
                         BackupDecryptionKey, Changes, DehydratedDeviceKey, DeviceChanges,
-                        IdentityChanges, PendingChanges, StoredRoomKeyBundleData, RoomSettings,
+                        IdentityChanges, PendingChanges, StoredRoomKeyBundleData, RoomKeyWithheldEntry,
+                        RoomSettings
                     },
                     CryptoStore, GossipRequest,
                 },
@@ -1138,7 +1139,7 @@ macro_rules! cryptostore_integration_tests {
             async fn test_withheld_info_storage() {
                 let (account, store) = get_loaded_store("withheld_info_storage").await;
 
-                let mut info_list: BTreeMap<_, BTreeMap<_, _>> = BTreeMap::new();
+                let mut info_list: BTreeMap<_, BTreeMap<_, RoomKeyWithheldEntry>> = BTreeMap::new();
 
                 let user_id = account.user_id().to_owned();
                 let room_id = room_id!("!DwLygpkclUAfQNnfva:example.com");
@@ -1163,7 +1164,7 @@ macro_rules! cryptostore_integration_tests {
                 info_list
                     .entry(room_id.to_owned())
                     .or_default()
-                    .insert(session_id_1.to_owned(), event);
+                    .insert(session_id_1.to_owned(), event.into());
 
                 let content = RoomKeyWithheldContent::MegolmV1AesSha2(
                     MegolmV1AesSha2WithheldContent::BlackListed(
@@ -1183,7 +1184,7 @@ macro_rules! cryptostore_integration_tests {
                 info_list
                     .entry(room_id.to_owned())
                     .or_default()
-                    .insert(session_id_2.to_owned(), event);
+                    .insert(session_id_2.to_owned(), event.into());
 
                 let changes = Changes { withheld_session_info: info_list, ..Default::default() };
                 store.save_changes(changes).await.unwrap();

crates/matrix-sdk-crypto/src/store/memorystore.rs

@@ -45,7 +45,7 @@ use crate::{
         OutboundGroupSession, PickledAccount, PickledInboundGroupSession, PickledSession,
         PrivateCrossSigningIdentity, SenderDataType, StaticAccountData,
     },
-    types::events::room_key_withheld::RoomKeyWithheldEvent,
+    store::types::RoomKeyWithheldEntry,
 };
 
 fn encode_key_info(info: &SecretInfo) -> String {
@@ -97,7 +97,7 @@ pub struct MemoryStore {
     identities: StdRwLock<HashMap<OwnedUserId, String>>,
     outgoing_key_requests: StdRwLock<HashMap<OwnedTransactionId, GossipRequest>>,
     key_requests_by_info: StdRwLock<HashMap<String, OwnedTransactionId>>,
-    direct_withheld_info: StdRwLock<HashMap<OwnedRoomId, HashMap<String, RoomKeyWithheldEvent>>>,
+    direct_withheld_info: StdRwLock<HashMap<OwnedRoomId, HashMap<String, RoomKeyWithheldEntry>>>,
     custom_values: StdRwLock<HashMap<String, Vec<u8>>>,
     leases: StdRwLock<HashMap<String, (String, Instant)>>,
     secret_inbox: StdRwLock<HashMap<String, Vec<GossippedSecret>>>,
@@ -420,7 +420,7 @@ impl CryptoStore for MemoryStore {
         &self,
         room_id: &RoomId,
         session_id: &str,
-    ) -> Result<Option<RoomKeyWithheldEvent>> {
+    ) -> Result<Option<RoomKeyWithheldEntry>> {
         Ok(self
             .direct_withheld_info
             .read()
@@ -1272,11 +1272,10 @@ mod integration_tests {
         store::{
             types::{
                 BackupKeys, Changes, DehydratedDeviceKey, PendingChanges, RoomKeyCounts,
-                RoomSettings, StoredRoomKeyBundleData, TrackedUser,
+                RoomKeyWithheldEntry, RoomSettings, StoredRoomKeyBundleData, TrackedUser,
             },
             CryptoStore,
         },
-        types::events::room_key_withheld::RoomKeyWithheldEvent,
         Account, DeviceData, GossipRequest, GossippedSecret, SecretInfo, Session, UserIdentityData,
     };
 
@@ -1372,7 +1371,7 @@ mod integration_tests {
             &self,
             room_id: &RoomId,
             session_id: &str,
-        ) -> Result<Option<RoomKeyWithheldEvent>, Self::Error> {
+        ) -> Result<Option<RoomKeyWithheldEntry>, Self::Error> {
             self.0.get_withheld_info(room_id, session_id).await
         }