Don't include access tokens where the referenced device has vanished

Author: reivilibre

crates/syn2mas/src/synapse_reader/mod.rs

@@ -479,6 +479,12 @@ impl<'conn> SynapseReader<'conn> {
     /// Reads unrefreshable access tokens from the Synapse database.
     /// This does not include access tokens used for puppetting users, as those
     /// are not supported by MAS.
+    ///
+    /// This also excludes access tokens whose referenced device ID does not exist,
+    /// except for deviceless access tokens.
+    /// (It's unclear what mechanism led to these, but since Synapse has no
+    /// foreign key constraints and is not consistently atomic about this,
+    /// it should be no surprise really)
     pub fn read_unrefreshable_access_tokens(
         &mut self,
     ) -> impl Stream<Item = Result<SynapseAccessToken, Error>> + '_ {
@@ -487,7 +493,15 @@ impl<'conn> SynapseReader<'conn> {
             SELECT
               at0.user_id, at0.device_id, at0.token, at0.valid_until_ms, at0.last_validated
             FROM access_tokens at0
+            INNER JOIN devices USING (user_id, device_id)
             WHERE at0.puppets_user_id IS NULL AND at0.refresh_token_id IS NULL
+
+            UNION
+
+            SELECT
+              at0.user_id, at0.device_id, at0.token, at0.valid_until_ms, at0.last_validated
+            FROM access_tokens at0
+            WHERE at0.puppets_user_id IS NULL AND at0.refresh_token_id IS NULL AND at0.device_id IS NULL
             ",
         )
         .fetch(&mut *self.txn)
@@ -511,6 +525,7 @@ impl<'conn> SynapseReader<'conn> {
             SELECT
               rt0.user_id, rt0.device_id, at0.token AS access_token, rt0.token AS refresh_token, at0.valid_until_ms, at0.last_validated
             FROM refresh_tokens rt0
+            INNER JOIN devices USING (device_id)
             INNER JOIN access_tokens at0 ON at0.refresh_token_id = rt0.id AND at0.user_id = rt0.user_id AND at0.device_id = rt0.device_id
             LEFT JOIN access_tokens at1 ON at1.refresh_token_id = rt0.next_token_id
             WHERE NOT at1.used OR at1.used IS NULL