crypto: use new withheldcode when we encounter unshareable sessions

Author: richvdh

crates/matrix-sdk-crypto/CHANGELOG.md

@@ -8,6 +8,9 @@ All notable changes to this project will be documented in this file.
 
 ### Features
 
+- Use new withheld code in key bundles for sessions not marked as
+  `shared_history`.
+  ([#5807](https://github.com/matrix-org/matrix-rust-sdk/pull/5807)
 - Improve 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

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

@@ -1600,7 +1600,7 @@ impl Store {
             } else {
                 bundle.withheld.push(RoomKeyWithheldContent::new(
                     session.algorithm().to_owned(),
-                    WithheldCode::Unauthorised,
+                    WithheldCode::HistoryNotShared,
                     session.room_id().to_owned(),
                     session.session_id().to_owned(),
                     session.sender_key().to_owned(),
@@ -2154,11 +2154,11 @@ mod tests {
             RoomKeyWithheldEntry {
                 #[cfg(not(feature = "experimental-algorithms"))]
                 content: RoomKeyWithheldContent::MegolmV1AesSha2(
-                    MegolmV1AesSha2WithheldContent::Unauthorised(_)
+                    MegolmV1AesSha2WithheldContent::HistoryNotShared(_)
                 ),
                 #[cfg(feature = "experimental-algorithms")]
                 content: RoomKeyWithheldContent::MegolmV2AesSha2(
-                    MegolmV1AesSha2WithheldContent::Unauthorised(_)
+                    MegolmV1AesSha2WithheldContent::HistoryNotShared(_)
                 ),
                 ..
             }

crates/matrix-sdk-crypto/src/store/snapshots/matrix_sdk_crypto__store__tests__build_room_key_bundle.snap

@@ -28,9 +28,9 @@ expression: bundle
   "withheld": [
     {
       "algorithm": "[algorithm]",
-      "code": "m.unauthorised",
+      "code": "io.element.msc4268.history_not_shared",
       "from_device": "BOB",
-      "reason": "You are not authorised to read the message.",
+      "reason": "The sender disabled sharing encrypted history.",
       "room_id": "!room1:localhost",
       "sender_key": "[alice curve key]",
       "session_id": "lpRzTgD3Nook/Wk62Fm9ECWGnKYZgeCwO1Y+uuPJz/I"