Merge pull request #2559 from matrix-org/erikj/group_id_validation

Add config to enable group creation

3 files changed, 46 insertions, 3 deletions

diff --git a/synapse/config/groups.py b/synapse/config/groups.py
new file mode 100644
index 0000000000..997fa2881f
--- /dev/null
+++ b/synapse/config/groups.py
@@ -0,0 +1,32 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector 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 ._base import Config
+
+
+class GroupsConfig(Config):
+    def read_config(self, config):
+        self.enable_group_creation = config.get("enable_group_creation", False)
+        self.group_creation_prefix = config.get("group_creation_prefix", "")
+
+    def default_config(self, **kwargs):
+        return """\
+        # Whether to allow non server admins to create groups on this server
+        enable_group_creation: false
+
+        # If enabled, non server admins can only create groups with local parts
+        # starting with this prefix
+        # group_creation_prefix: "unofficial/"
+        """
diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py
index 3f9d9d5f8b..05e242aef6 100644
--- a/synapse/config/homeserver.py
+++ b/synapse/config/homeserver.py
@@ -35,6 +35,7 @@ from .emailconfig import EmailConfig
 from .workers import WorkerConfig
 from .push import PushConfig
 from .spam_checker import SpamCheckerConfig
+from .groups import GroupsConfig
 
 
 class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
@@ -43,7 +44,7 @@ class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
                        AppServiceConfig, KeyConfig, SAML2Config, CasConfig,
                        JWTConfig, PasswordConfig, EmailConfig,
                        WorkerConfig, PasswordAuthProviderConfig, PushConfig,
-                       SpamCheckerConfig,):
+                       SpamCheckerConfig, GroupsConfig,):
     pass
 
 
diff --git a/synapse/groups/groups_server.py b/synapse/groups/groups_server.py
index e9b44c0971..fc4edb7f04 100644
--- a/synapse/groups/groups_server.py
+++ b/synapse/groups/groups_server.py
@@ -704,10 +704,20 @@ class GroupsServerHandler(object):
         if group:
             raise SynapseError(400, "Group already exists")
 
-        # TODO: Add config to enforce that only server admins can create rooms
         is_admin = yield self.auth.is_server_admin(UserID.from_string(user_id))
         if not is_admin:
-            raise SynapseError(403, "Only server admin can create group on this server")
+            if not self.hs.config.enable_group_creation:
+                raise SynapseError(
+                    403, "Only server admin can create group on this server",
+                )
+            localpart = GroupID.from_string(group_id).localpart
+            if not localpart.startswith(self.hs.config.group_creation_prefix):
+                raise SynapseError(
+                    400,
+                    "Can only create groups with prefix %r on this server" % (
+                        self.hs.config.group_creation_prefix,
+                    ),
+                )
 
         profile = content.get("profile", {})
         name = profile.get("name")