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authorPaul "LeoNerd" Evans <paul@matrix.org>2015-04-27 17:09:25 +0100
committerPaul "LeoNerd" Evans <paul@matrix.org>2015-04-27 17:09:25 +0100
commit38432d8c253fda453cd645491f46ef37714c4f7c (patch)
tree76d9f0dee077b01038a939f611fbcb4b89aea496
parentAlso remember to check 'invite' level for changes (diff)
parentMerge pull request #132 from matrix-org/observer_and_locks (diff)
downloadsynapse-38432d8c253fda453cd645491f46ef37714c4f7c.tar.xz
Merge branch 'develop' into invite_power_level
Diffstat (limited to '')
-rw-r--r--README.rst17
-rw-r--r--UPGRADE.rst34
-rw-r--r--docs/metrics-howto.rst50
-rw-r--r--synapse/api/auth.py48
-rw-r--r--synapse/api/errors.py4
-rw-r--r--synapse/config/registration.py1
-rw-r--r--synapse/crypto/keyring.py20
-rw-r--r--synapse/handlers/presence.py51
-rw-r--r--synapse/push/baserules.py56
-rw-r--r--synapse/push/rulekinds.py14
-rw-r--r--synapse/python_dependencies.py14
-rw-r--r--synapse/rest/media/v1/base_resource.py4
-rw-r--r--synapse/rest/media/v1/identicon_resource.py14
-rw-r--r--synapse/storage/schema/delta/14/upgrade_appservice_db.py14
-rw-r--r--synapse/storage/schema/delta/14/v14.sql14
-rw-r--r--synapse/util/async.py19
-rw-r--r--tests/handlers/test_presence.py65
17 files changed, 366 insertions, 73 deletions
diff --git a/README.rst b/README.rst
index 14ef6c5acf..714ad6443d 100644
--- a/README.rst
+++ b/README.rst
@@ -86,7 +86,7 @@ Homeserver Installation
 =======================
 
 System requirements:
-- POSIX-compliant system (tested on Linux & OSX)
+- POSIX-compliant system (tested on Linux & OS X)
 - Python 2.7
 
 Synapse is written in python but some of the libraries is uses are written in
@@ -128,6 +128,15 @@ To set up your homeserver, run (in your virtualenv, as before)::
 
 Substituting your host and domain name as appropriate.
 
+This will generate you a config file that you can then customise, but it will
+also generate a set of keys for you. These keys will allow your Home Server to
+identify itself to other Home Servers, so don't lose or delete them. It would be
+wise to back them up somewhere safe. If, for whatever reason, you do need to
+change your Home Server's keys, you may find that other Home Servers have the
+old key cached. If you update the signing key, you should change the name of the
+key in the <server name>.signing.key file (the second word, which by default is
+, 'auto') to something different.
+
 By default, registration of new users is disabled. You can either enable
 registration in the config by specifying ``enable_registration: true``
 (it is then recommended to also set up CAPTCHA), or
@@ -367,10 +376,6 @@ SRV record, as that is the name other machines will expect it to have::
 You may additionally want to pass one or more "-v" options, in order to
 increase the verbosity of logging output; at least for initial testing.
 
-For the initial alpha release, the homeserver is not speaking TLS for
-either client-server or server-server traffic for ease of debugging. We have
-also not spent any time yet getting the homeserver to run behind loadbalancers.
-
 Running a Demo Federation of Homeservers
 ----------------------------------------
 
@@ -433,7 +438,7 @@ track 3PID logins and publish end-user public keys.
 
 It's currently early days for identity servers as Matrix is not yet using 3PIDs
 as the primary means of identity and E2E encryption is not complete. As such,
-we are running a single identity server (http://matrix.org:8090) at the current
+we are running a single identity server (https://matrix.org) at the current
 time.
 
 
diff --git a/UPGRADE.rst b/UPGRADE.rst
index 87dd6e04a8..ab327a8136 100644
--- a/UPGRADE.rst
+++ b/UPGRADE.rst
@@ -1,3 +1,37 @@
+Upgrading to v0.x.x
+===================
+
+Application services have had a breaking API change in this version.
+
+They can no longer register themselves with a home server using the AS HTTP API. This
+decision was made because a compromised application service with free reign to register
+any regex in effect grants full read/write access to the home server if a regex of ``.*``
+is used. An attack where a compromised AS re-registers itself with ``.*`` was deemed too
+big of a security risk to ignore, and so the ability to register with the HS remotely has
+been removed.
+
+It has been replaced by specifying a list of application service registrations in
+``homeserver.yaml``::
+
+  app_service_config_files: ["registration-01.yaml", "registration-02.yaml"]
+  
+Where ``registration-01.yaml`` looks like::
+
+  url: <String>  # e.g. "https://my.application.service.com"
+  as_token: <String>
+  hs_token: <String>
+  sender_localpart: <String>  # This is a new field which denotes the user_id localpart when using the AS token
+  namespaces:
+    users:
+      - exclusive: <Boolean>
+        regex: <String>  # e.g. "@prefix_.*"
+    aliases:
+      - exclusive: <Boolean>
+        regex: <String>
+    rooms:
+      - exclusive: <Boolean>
+        regex: <String>
+
 Upgrading to v0.8.0
 ===================
 
diff --git a/docs/metrics-howto.rst b/docs/metrics-howto.rst
new file mode 100644
index 0000000000..c1f5ae2174
--- /dev/null
+++ b/docs/metrics-howto.rst
@@ -0,0 +1,50 @@
+How to monitor Synapse metrics using Prometheus
+===============================================
+
+1: Install prometheus:
+  Follow instructions at http://prometheus.io/docs/introduction/install/
+
+2: Enable synapse metrics:
+  Simply setting a (local) port number will enable it. Pick a port.
+  prometheus itself defaults to 9090, so starting just above that for
+  locally monitored services seems reasonable. E.g. 9092:
+
+  Add to homeserver.yaml
+
+    metrics_port: 9092
+
+  Restart synapse
+
+3: Check out synapse-prometheus-config
+  https://github.com/matrix-org/synapse-prometheus-config
+
+4: Add ``synapse.html`` and ``synapse.rules``
+  The ``.html`` file needs to appear in prometheus's ``consoles`` directory,
+  and the ``.rules`` file needs to be invoked somewhere in the main config
+  file. A symlink to each from the git checkout into the prometheus directory
+  might be easiest to ensure ``git pull`` keeps it updated.
+
+5: Add a prometheus target for synapse
+  This is easiest if prometheus runs on the same machine as synapse, as it can
+  then just use localhost::
+
+    global: {
+      rule_file: "synapse.rules"
+    }
+
+    job: {
+      name: "synapse"
+
+      target_group: {
+        target: "http://localhost:9092/"
+      }
+    }
+
+6: Start prometheus::
+
+   ./prometheus -config.file=prometheus.conf
+
+7: Wait a few seconds for it to start and perform the first scrape,
+   then visit the console:
+
+    http://server-where-prometheus-runs:9090/consoles/synapse.html
diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index d8b7614791..935dffbabe 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -183,17 +183,7 @@ class Auth(object):
         else:
             join_rule = JoinRules.INVITE
 
-        user_level = self._get_power_level_from_event_state(
-            event,
-            event.user_id,
-            auth_events,
-        )
-
-        # TODO(paul): There's an awful lot of int()-casting in this code;
-        #   surely we should be squashing strings to integers at a higher
-        #   level, maybe when we insert?
-        if user_level is not None:
-            user_level = int(user_level)
+        user_level = self._get_user_power_level(event.user_id, auth_events)
 
         # FIXME (erikj): What should we do here as the default?
         ban_level = self._get_named_level(auth_events, "ban", 50)
@@ -281,23 +271,26 @@ class Auth(object):
         key = (EventTypes.PowerLevels, "", )
         return auth_events.get(key)
 
-    def _get_power_level_from_event_state(self, event, user_id, auth_events):
+    def _get_user_power_level(self, user_id, auth_events):
         power_level_event = self._get_power_level_event(auth_events)
-        level = None
 
         if power_level_event:
             level = power_level_event.content.get("users", {}).get(user_id)
             if not level:
                 level = power_level_event.content.get("users_default", 0)
+
+            if level is None:
+                return 0
+            else:
+                return int(level)
         else:
             key = (EventTypes.Create, "", )
             create_event = auth_events.get(key)
             if (create_event is not None and
                     create_event.content["creator"] == user_id):
                 return 100
-
-        return level
-
+            else:
+                return 0
 
     def _get_named_level(self, auth_events, name, default):
         power_level_event = self._get_power_level_event(auth_events)
@@ -504,16 +497,7 @@ class Auth(object):
         else:
             send_level = 0
 
-        user_level = self._get_power_level_from_event_state(
-            event,
-            event.user_id,
-            auth_events,
-        )
-
-        if user_level:
-            user_level = int(user_level)
-        else:
-            user_level = 0
+        user_level = self._get_user_power_level(event.user_id, auth_events)
 
         if user_level < send_level:
             raise AuthError(
@@ -545,11 +529,7 @@ class Auth(object):
         return True
 
     def _check_redaction(self, event, auth_events):
-        user_level = self._get_power_level_from_event_state(
-            event,
-            event.user_id,
-            auth_events,
-        )
+        user_level = self._get_user_power_level(event.user_id, auth_events)
 
         redact_level = self._get_named_level(auth_events, "redact", 50)
 
@@ -579,11 +559,7 @@ class Auth(object):
         if not current_state:
             return
 
-        user_level = self._get_power_level_from_event_state(
-            event,
-            event.user_id,
-            auth_events,
-        )
+        user_level = self._get_user_power_level(event.user_id, auth_events)
 
         # Check other levels:
         levels_to_check = [
diff --git a/synapse/api/errors.py b/synapse/api/errors.py
index eddd889778..72d2bd5b4c 100644
--- a/synapse/api/errors.py
+++ b/synapse/api/errors.py
@@ -35,8 +35,8 @@ class Codes(object):
     LIMIT_EXCEEDED = "M_LIMIT_EXCEEDED"
     CAPTCHA_NEEDED = "M_CAPTCHA_NEEDED"
     CAPTCHA_INVALID = "M_CAPTCHA_INVALID"
-    MISSING_PARAM = "M_MISSING_PARAM",
-    TOO_LARGE = "M_TOO_LARGE",
+    MISSING_PARAM = "M_MISSING_PARAM"
+    TOO_LARGE = "M_TOO_LARGE"
     EXCLUSIVE = "M_EXCLUSIVE"
 
 
diff --git a/synapse/config/registration.py b/synapse/config/registration.py
index d5c8f4bf7b..f412a72f59 100644
--- a/synapse/config/registration.py
+++ b/synapse/config/registration.py
@@ -53,6 +53,7 @@ class RegistrationConfig(Config):
 
     @classmethod
     def generate_config(cls, args, config_dir_path):
+        super(RegistrationConfig, cls).generate_config(args, config_dir_path)
         if args.enable_registration is None:
             args.enable_registration = False
 
diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py
index f4db7b8a05..2b4faee4c1 100644
--- a/synapse/crypto/keyring.py
+++ b/synapse/crypto/keyring.py
@@ -24,6 +24,8 @@ from synapse.api.errors import SynapseError, Codes
 
 from synapse.util.retryutils import get_retry_limiter
 
+from synapse.util.async import create_observer
+
 from OpenSSL import crypto
 
 import logging
@@ -38,6 +40,8 @@ class Keyring(object):
         self.clock = hs.get_clock()
         self.hs = hs
 
+        self.key_downloads = {}
+
     @defer.inlineCallbacks
     def verify_json_for_server(self, server_name, json_object):
         logger.debug("Verifying for %s", server_name)
@@ -97,6 +101,22 @@ class Keyring(object):
             defer.returnValue(cached[0])
             return
 
+        download = self.key_downloads.get(server_name)
+
+        if download is None:
+            download = self._get_server_verify_key_impl(server_name, key_ids)
+            self.key_downloads[server_name] = download
+
+            @download.addBoth
+            def callback(ret):
+                del self.key_downloads[server_name]
+                return ret
+
+        r = yield create_observer(download)
+        defer.returnValue(r)
+
+    @defer.inlineCallbacks
+    def _get_server_verify_key_impl(self, server_name, key_ids):
         # Try to fetch the key from the remote server.
 
         limiter = yield get_retry_limiter(
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index bbc7a0f200..571eacd343 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -36,6 +36,9 @@ metrics = synapse.metrics.get_metrics_for(__name__)
 # Don't bother bumping "last active" time if it differs by less than 60 seconds
 LAST_ACTIVE_GRANULARITY = 60*1000
 
+# Keep no more than this number of offline serial revisions
+MAX_OFFLINE_SERIALS = 1000
+
 
 # TODO(paul): Maybe there's one of these I can steal from somewhere
 def partition(l, func):
@@ -135,6 +138,9 @@ class PresenceHandler(BaseHandler):
         self._remote_sendmap = {}
         # map remote users to sets of local users who're interested in them
         self._remote_recvmap = {}
+        # list of (serial, set of(userids)) tuples, ordered by serial, latest
+        # first
+        self._remote_offline_serials = []
 
         # map any user to a UserPresenceCache
         self._user_cachemap = {}
@@ -714,8 +720,24 @@ class PresenceHandler(BaseHandler):
                 statuscache=statuscache,
             )
 
+            user_id = user.to_string()
+
             if state["presence"] == PresenceState.OFFLINE:
+                self._remote_offline_serials.insert(
+                    0,
+                    (self._user_cachemap_latest_serial, set([user_id]))
+                )
+                while len(self._remote_offline_serials) > MAX_OFFLINE_SERIALS:
+                    self._remote_offline_serials.pop()  # remove the oldest
                 del self._user_cachemap[user]
+            else:
+                # Remove the user from remote_offline_serials now that they're
+                # no longer offline
+                for idx, elem in enumerate(self._remote_offline_serials):
+                    (_, user_ids) = elem
+                    user_ids.discard(user_id)
+                    if not user_ids:
+                        self._remote_offline_serials.pop(idx)
 
         for poll in content.get("poll", []):
             user = UserID.from_string(poll)
@@ -836,6 +858,8 @@ class PresenceEventSource(object):
 
         presence = self.hs.get_handlers().presence_handler
         cachemap = presence._user_cachemap
+        clock = self.clock
+        latest_serial = None
 
         updates = []
         # TODO(paul): use a DeferredList ? How to limit concurrency.
@@ -845,18 +869,31 @@ class PresenceEventSource(object):
             if cached.serial <= from_key:
                 continue
 
-            if (yield self.is_visible(observer_user, observed_user)):
-                updates.append((observed_user, cached))
+            if not (yield self.is_visible(observer_user, observed_user)):
+                continue
+
+            if latest_serial is None or cached.serial > latest_serial:
+                latest_serial = cached.serial
+            updates.append(cached.make_event(user=observed_user, clock=clock))
 
         # TODO(paul): limit
 
-        if updates:
-            clock = self.clock
+        for serial, user_ids in presence._remote_offline_serials:
+            if serial < from_key:
+                break
 
-            latest_serial = max([x[1].serial for x in updates])
-            data = [x[1].make_event(user=x[0], clock=clock) for x in updates]
+            for u in user_ids:
+                updates.append({
+                    "type": "m.presence",
+                    "content": {"user_id": u, "presence": PresenceState.OFFLINE},
+                })
+        # TODO(paul): For the v2 API we want to tell the client their from_key
+        #   is too old if we fell off the end of the _remote_offline_serials
+        #   list, and get them to invalidate+resync. In v1 we have no such
+        #   concept so this is a best-effort result.
 
-            defer.returnValue((data, latest_serial))
+        if updates:
+            defer.returnValue((updates, latest_serial))
         else:
             defer.returnValue(([], presence._user_cachemap_latest_serial))
 
diff --git a/synapse/push/baserules.py b/synapse/push/baserules.py
index 60fd35fbfb..f3d1cf5c5f 100644
--- a/synapse/push/baserules.py
+++ b/synapse/push/baserules.py
@@ -1,3 +1,17 @@
+# Copyright 2015 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 from synapse.push.rulekinds import PRIORITY_CLASS_MAP, PRIORITY_CLASS_INVERSE_MAP
 
 
@@ -112,7 +126,25 @@ def make_base_prepend_override_rules():
 def make_base_append_override_rules():
     return [
         {
-            'rule_id': 'global/override/.m.rule.call',
+            'rule_id': 'global/override/.m.rule.suppress_notices',
+            'conditions': [
+                {
+                    'kind': 'event_match',
+                    'key': 'content.msgtype',
+                    'pattern': 'm.notice',
+                }
+            ],
+            'actions': [
+                'dont_notify',
+            ]
+        }
+    ]
+
+
+def make_base_append_underride_rules(user):
+    return [
+        {
+            'rule_id': 'global/underride/.m.rule.call',
             'conditions': [
                 {
                     'kind': 'event_match',
@@ -132,19 +164,6 @@ def make_base_append_override_rules():
             ]
         },
         {
-            'rule_id': 'global/override/.m.rule.suppress_notices',
-            'conditions': [
-                {
-                    'kind': 'event_match',
-                    'key': 'content.msgtype',
-                    'pattern': 'm.notice',
-                }
-            ],
-            'actions': [
-                'dont_notify',
-            ]
-        },
-        {
             'rule_id': 'global/override/.m.rule.contains_display_name',
             'conditions': [
                 {
@@ -162,7 +181,7 @@ def make_base_append_override_rules():
             ]
         },
         {
-            'rule_id': 'global/override/.m.rule.room_one_to_one',
+            'rule_id': 'global/underride/.m.rule.room_one_to_one',
             'conditions': [
                 {
                     'kind': 'room_member_count',
@@ -179,12 +198,7 @@ def make_base_append_override_rules():
                     'value': False
                 }
             ]
-        }
-    ]
-
-
-def make_base_append_underride_rules(user):
-    return [
+        },
         {
             'rule_id': 'global/underride/.m.rule.invite_for_me',
             'conditions': [
diff --git a/synapse/push/rulekinds.py b/synapse/push/rulekinds.py
index 660aa4e10e..4c591aa638 100644
--- a/synapse/push/rulekinds.py
+++ b/synapse/push/rulekinds.py
@@ -1,3 +1,17 @@
+# Copyright 2015 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 PRIORITY_CLASS_MAP = {
     'underride': 1,
     'sender': 2,
diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py
index ee72f774b3..8b457419cf 100644
--- a/synapse/python_dependencies.py
+++ b/synapse/python_dependencies.py
@@ -1,3 +1,17 @@
+# Copyright 2015 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import logging
 from distutils.version import LooseVersion
 
diff --git a/synapse/rest/media/v1/base_resource.py b/synapse/rest/media/v1/base_resource.py
index edd4f78024..08c8d75af4 100644
--- a/synapse/rest/media/v1/base_resource.py
+++ b/synapse/rest/media/v1/base_resource.py
@@ -25,6 +25,8 @@ from twisted.internet import defer
 from twisted.web.resource import Resource
 from twisted.protocols.basic import FileSender
 
+from synapse.util.async import create_observer
+
 import os
 
 import logging
@@ -87,7 +89,7 @@ class BaseMediaResource(Resource):
             def callback(media_info):
                 del self.downloads[key]
                 return media_info
-        return download
+        return create_observer(download)
 
     @defer.inlineCallbacks
     def _get_remote_media_impl(self, server_name, media_id):
diff --git a/synapse/rest/media/v1/identicon_resource.py b/synapse/rest/media/v1/identicon_resource.py
index 912856386a..603859d5d4 100644
--- a/synapse/rest/media/v1/identicon_resource.py
+++ b/synapse/rest/media/v1/identicon_resource.py
@@ -1,3 +1,17 @@
+# Copyright 2015 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 from pydenticon import Generator
 from twisted.web.resource import Resource
 
diff --git a/synapse/storage/schema/delta/14/upgrade_appservice_db.py b/synapse/storage/schema/delta/14/upgrade_appservice_db.py
index 847b1c5b89..9f3a4dd4c5 100644
--- a/synapse/storage/schema/delta/14/upgrade_appservice_db.py
+++ b/synapse/storage/schema/delta/14/upgrade_appservice_db.py
@@ -1,3 +1,17 @@
+# Copyright 2015 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import json
 import logging
 
diff --git a/synapse/storage/schema/delta/14/v14.sql b/synapse/storage/schema/delta/14/v14.sql
index 0212726448..1d09ad7a15 100644
--- a/synapse/storage/schema/delta/14/v14.sql
+++ b/synapse/storage/schema/delta/14/v14.sql
@@ -1,3 +1,17 @@
+/* Copyright 2015 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 CREATE TABLE IF NOT EXISTS push_rules_enable (
   id INTEGER PRIMARY KEY AUTOINCREMENT,
   user_name TEXT NOT NULL,
diff --git a/synapse/util/async.py b/synapse/util/async.py
index c4fe5d522f..d8febdb90c 100644
--- a/synapse/util/async.py
+++ b/synapse/util/async.py
@@ -32,3 +32,22 @@ def run_on_reactor():
     iteration of the main loop
     """
     return sleep(0)
+
+
+def create_observer(deferred):
+    """Creates a deferred that observes the result or failure of the given
+     deferred *without* affecting the given deferred.
+    """
+    d = defer.Deferred()
+
+    def callback(r):
+        d.callback(r)
+        return r
+
+    def errback(f):
+        d.errback(f)
+        return f
+
+    deferred.addCallbacks(callback, errback)
+
+    return d
diff --git a/tests/handlers/test_presence.py b/tests/handlers/test_presence.py
index 04eba4289e..9f5580c096 100644
--- a/tests/handlers/test_presence.py
+++ b/tests/handlers/test_presence.py
@@ -879,6 +879,71 @@ class PresencePushTestCase(MockedDatastorePresenceTestCase):
         )
 
     @defer.inlineCallbacks
+    def test_recv_remote_offline(self):
+        """ Various tests relating to SYN-261 """
+        potato_set = self.handler._remote_recvmap.setdefault(self.u_potato,
+                set())
+        potato_set.add(self.u_apple)
+
+        self.room_members = [self.u_banana, self.u_potato]
+
+        self.assertEquals(self.event_source.get_current_key(), 0)
+
+        yield self.mock_federation_resource.trigger("PUT",
+            "/_matrix/federation/v1/send/1000000/",
+            _make_edu_json("elsewhere", "m.presence",
+                content={
+                    "push": [
+                        {"user_id": "@potato:remote",
+                         "presence": "offline"},
+                    ],
+                }
+            )
+        )
+
+        self.assertEquals(self.event_source.get_current_key(), 1)
+
+        (events, _) = yield self.event_source.get_new_events_for_user(
+            self.u_apple, 0, None
+        )
+        self.assertEquals(events,
+            [
+                {"type": "m.presence",
+                 "content": {
+                     "user_id": "@potato:remote",
+                     "presence": OFFLINE,
+                }}
+            ]
+        )
+
+        yield self.mock_federation_resource.trigger("PUT",
+            "/_matrix/federation/v1/send/1000001/",
+            _make_edu_json("elsewhere", "m.presence",
+                content={
+                    "push": [
+                        {"user_id": "@potato:remote",
+                         "presence": "online"},
+                    ],
+                }
+            )
+        )
+
+        self.assertEquals(self.event_source.get_current_key(), 2)
+
+        (events, _) = yield self.event_source.get_new_events_for_user(
+            self.u_apple, 0, None
+        )
+        self.assertEquals(events,
+            [
+                {"type": "m.presence",
+                 "content": {
+                     "user_id": "@potato:remote",
+                     "presence": ONLINE,
+                }}
+            ]
+        )
+
+    @defer.inlineCallbacks
     def test_join_room_local(self):
         self.room_members = [self.u_apple, self.u_banana]