Manual ownership transfers between two federated instances diverged because
`dm_channels.ownerHomeInstance` was stored as a BARE host (`orbit.ddns.net`)
for federated owners — via `transferGroupDmOwnership` copying `users.homeInstance`
verbatim — while `sourceInstance` always arrives as a full URL on the wire.
`processOwnershipTransferEvent` and `processMemberRemoveEvent` then compared the
two with strict equality and rejected legitimate inbound events as
`unauthorized_source`, keeping ownership permanently divergent across peers.
Live DB inspection on the two test instances confirmed both rows (nova + orbit)
had a BARE `owner_home_instance`, matching the bug report exactly.
Three compounding fixes:
1. Receiver authority checks now compare via `normalizeOriginForCompare` so
legacy bare-vs-full rows accept legitimate transfers (and kicks).
2. New `canonicalizeHomeInstance` helper in `federationAuth.ts`; every write
site that persists `ownerHomeInstance` (`transferGroupDmOwnership`, group DM
creation, lazy federation in member-add, `processMemberAddEvent` bootstrap,
`processOwnershipTransferEvent` receiver storage) routes through it. Full URL
is the canonical storage form, matching how `sourceInstance` arrives.
3. `dm_owner_updated` WS event extended with optional `newOwnerHomeUserId` and
`newOwnerHomeInstance` fields. Client `updateDmOwner` writes them when
present and leaves existing values untouched otherwise (legacy-server safe).
Without this, `getOwnerInstanceForDm` returned the previous owner's home
after a successful WS broadcast, routing the next owner-only op to the wrong
instance.
Coverage: new `federation.ownershipTransfer.test.ts` (7 receiver tests including
the headline bare-vs-full regression and the dedup replay guard); new bare-vs-full
case in `federation.kick.test.ts`; two new client-side cases in
`groupDm.ownerRouting.test.ts` covering both the extended-payload write path and
the legacy-server passthrough. Tests: 1053 server + 364 web, all green.
Specs updated: `dm-system.md` historical bugs + frontend handler table + WS
state-change events table; `federation.md` `ownership_transfer` receiver flow;
`websocket.md` event-fields table.
Jannis Braun
3c7bb02901