Merge tag 'v1.39.0rc3' into develop

Synapse 1.39.0rc3 (2021-07-28)
==============================

Bugfixes
--------

- Fix a bug introduced in Synapse 1.38 which caused an exception at startup when SAML authentication was enabled. ([\#10477](https://github.com/matrix-org/synapse/issues/10477))
- Fix a long-standing bug where Synapse would not inform clients that a device had exhausted its one-time-key pool, potentially causing problems decrypting events. ([\#10485](https://github.com/matrix-org/synapse/issues/10485))
- Fix reporting old R30 stats as R30v2 stats. Introduced in v1.39.0rc1. ([\#10486](https://github.com/matrix-org/synapse/issues/10486))

Internal Changes
----------------

- Fix an error which prevented the Github Actions workflow to build the docker images from running. ([\#10461](https://github.com/matrix-org/synapse/issues/10461))
- Fix release script to correctly version debian changelog when doing RCs. ([\#10465](https://github.com/matrix-org/synapse/issues/10465))

6 files changed, 22 insertions, 5 deletions

diff --git a/synapse/__init__.py b/synapse/__init__.py
index 01d6bf17f0..c9a445c8fe 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -47,7 +47,7 @@ try:
 except ImportError:
     pass
 
-__version__ = "1.39.0rc2"
+__version__ = "1.39.0rc3"
 
 if bool(os.environ.get("SYNAPSE_TEST_PATCH_LOG_CONTEXTS", False)):
     # We import here so that we don't have to install a bunch of deps when
diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index 56e7233b9e..a40d6d7961 100644
--- a/synapse/api/constants.py
+++ b/synapse/api/constants.py
@@ -128,6 +128,14 @@ class ToDeviceEventTypes:
     RoomKeyRequest = "m.room_key_request"
 
 
+class DeviceKeyAlgorithms:
+    """Spec'd algorithms for the generation of per-device keys"""
+
+    ED25519 = "ed25519"
+    CURVE25519 = "curve25519"
+    SIGNED_CURVE25519 = "signed_curve25519"
+
+
 class EduTypes:
     Presence = "m.presence"
 
diff --git a/synapse/app/phone_stats_home.py b/synapse/app/phone_stats_home.py
index 96defac1d2..86ad7337a9 100644
--- a/synapse/app/phone_stats_home.py
+++ b/synapse/app/phone_stats_home.py
@@ -109,7 +109,7 @@ async def phone_stats_home(hs, stats, stats_process=_stats_process):
     for name, count in r30_results.items():
         stats["r30_users_" + name] = count
 
-    r30v2_results = await store.count_r30_users()
+    r30v2_results = await store.count_r30v2_users()
     for name, count in r30v2_results.items():
         stats["r30v2_users_" + name] = count
 
diff --git a/synapse/handlers/_base.py b/synapse/handlers/_base.py
index 525f3d39b1..6a05a65305 100644
--- a/synapse/handlers/_base.py
+++ b/synapse/handlers/_base.py
@@ -15,8 +15,6 @@
 import logging
 from typing import TYPE_CHECKING, Optional
 
-import synapse.state
-import synapse.storage
 import synapse.types
 from synapse.api.constants import EventTypes, Membership
 from synapse.api.ratelimiting import Ratelimiter
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index 150a4f291e..f30bfcc93c 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -1093,6 +1093,10 @@ class SyncHandler:
         one_time_key_counts: JsonDict = {}
         unused_fallback_key_types: List[str] = []
         if device_id:
+            # TODO: We should have a way to let clients differentiate between the states of:
+            #   * no change in OTK count since the provided since token
+            #   * the server has zero OTKs left for this device
+            #  Spec issue: https://github.com/matrix-org/matrix-doc/issues/3298
             one_time_key_counts = await self.store.count_e2e_one_time_keys(
                 user_id, device_id
             )
diff --git a/synapse/storage/databases/main/end_to_end_keys.py b/synapse/storage/databases/main/end_to_end_keys.py
index 78ae68ec68..1edc96042b 100644
--- a/synapse/storage/databases/main/end_to_end_keys.py
+++ b/synapse/storage/databases/main/end_to_end_keys.py
@@ -21,6 +21,7 @@ from canonicaljson import encode_canonical_json
 
 from twisted.enterprise.adbapi import Connection
 
+from synapse.api.constants import DeviceKeyAlgorithms
 from synapse.logging.opentracing import log_kv, set_tag, trace
 from synapse.storage._base import SQLBaseStore, db_to_json
 from synapse.storage.database import DatabasePool, make_in_list_sql_clause
@@ -381,9 +382,15 @@ class EndToEndKeyWorkerStore(EndToEndKeyBackgroundStore):
                 " GROUP BY algorithm"
             )
             txn.execute(sql, (user_id, device_id))
-            result = {}
+
+            # Initially set the key count to 0. This ensures that the client will always
+            # receive *some count*, even if it's 0.
+            result = {DeviceKeyAlgorithms.SIGNED_CURVE25519: 0}
+
+            # Override entries with the count of any keys we pulled from the database
             for algorithm, key_count in txn:
                 result[algorithm] = key_count
+
             return result
 
         return await self.db_pool.runInteraction(