Merge pull request #2561 from matrix-org/rav/id_checking

Updates to ID checking

3 files changed, 47 insertions, 33 deletions

diff --git a/synapse/groups/groups_server.py b/synapse/groups/groups_server.py
index fc4edb7f04..23beb3187e 100644
--- a/synapse/groups/groups_server.py
+++ b/synapse/groups/groups_server.py
@@ -13,14 +13,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from twisted.internet import defer
+import logging
 
 from synapse.api.errors import SynapseError
-from synapse.types import UserID, get_domain_from_id, RoomID, GroupID
-
-
-import logging
-import urllib
+from synapse.types import GroupID, RoomID, UserID, get_domain_from_id
+from twisted.internet import defer
 
 logger = logging.getLogger(__name__)
 
@@ -698,9 +695,11 @@ class GroupsServerHandler(object):
     def create_group(self, group_id, user_id, content):
         group = yield self.check_group_is_ours(group_id)
 
-        _validate_group_id(group_id)
-
         logger.info("Attempting to create group with ID: %r", group_id)
+
+        # parsing the id into a GroupID validates it.
+        group_id_obj = GroupID.from_string(group_id)
+
         if group:
             raise SynapseError(400, "Group already exists")
 
@@ -710,7 +709,7 @@ class GroupsServerHandler(object):
                 raise SynapseError(
                     403, "Only server admin can create group on this server",
                 )
-            localpart = GroupID.from_string(group_id).localpart
+            localpart = group_id_obj.localpart
             if not localpart.startswith(self.hs.config.group_creation_prefix):
                 raise SynapseError(
                     400,
@@ -786,18 +785,3 @@ def _parse_visibility_from_contents(content):
         is_public = True
 
     return is_public
-
-
-def _validate_group_id(group_id):
-    """Validates the group ID is valid for creation on this home server
-    """
-    localpart = GroupID.from_string(group_id).localpart
-
-    if localpart.lower() != localpart:
-        raise SynapseError(400, "Group ID must be lower case")
-
-    if urllib.quote(localpart.encode('utf-8')) != localpart:
-        raise SynapseError(
-            400,
-            "Group ID can only contain characters a-z, 0-9, or '_-./'",
-        )
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index 560fb36254..52aa9964d9 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -15,7 +15,6 @@
 
 """Contains functions for registering clients."""
 import logging
-import urllib
 
 from twisted.internet import defer
 
@@ -23,6 +22,7 @@ from synapse.api.errors import (
     AuthError, Codes, SynapseError, RegistrationError, InvalidCaptchaError
 )
 from synapse.http.client import CaptchaServerHttpClient
+from synapse import types
 from synapse.types import UserID
 from synapse.util.async import run_on_reactor
 from ._base import BaseHandler
@@ -46,12 +46,10 @@ class RegistrationHandler(BaseHandler):
     @defer.inlineCallbacks
     def check_username(self, localpart, guest_access_token=None,
                        assigned_user_id=None):
-        yield run_on_reactor()
-
-        if urllib.quote(localpart.encode('utf-8')) != localpart:
+        if types.contains_invalid_mxid_characters(localpart):
             raise SynapseError(
                 400,
-                "User ID can only contain characters a-z, 0-9, or '_-./'",
+                "User ID can only contain characters a-z, 0-9, or '=_-./'",
                 Codes.INVALID_USERNAME
             )
 
@@ -81,7 +79,7 @@ class RegistrationHandler(BaseHandler):
                     "A different user ID has already been registered for this session",
                 )
 
-        yield self.check_user_id_not_appservice_exclusive(user_id)
+        self.check_user_id_not_appservice_exclusive(user_id)
 
         users = yield self.store.get_users_by_id_case_insensitive(user_id)
         if users:
@@ -254,11 +252,10 @@ class RegistrationHandler(BaseHandler):
         """
         Registers email_id as SAML2 Based Auth.
         """
-        if urllib.quote(localpart) != localpart:
+        if types.contains_invalid_mxid_characters(localpart):
             raise SynapseError(
                 400,
-                "User ID must only contain characters which do not"
-                " require URL encoding."
+                "User ID can only contain characters a-z, 0-9, or '=_-./'",
             )
         user = UserID(localpart, self.hs.hostname)
         user_id = user.to_string()
diff --git a/synapse/types.py b/synapse/types.py
index 1aa426fcbb..1eeda0b72f 100644
--- a/synapse/types.py
+++ b/synapse/types.py
@@ -12,6 +12,7 @@
 # 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 string
 
 from synapse.api.errors import SynapseError
 
@@ -156,6 +157,38 @@ class GroupID(DomainSpecificString):
     """Structure representing a group ID."""
     SIGIL = "+"
 
+    @classmethod
+    def from_string(cls, s):
+        group_id = super(GroupID, cls).from_string(s)
+        if not group_id.localpart:
+            raise SynapseError(
+                400,
+                "Group ID cannot be empty",
+            )
+
+        if contains_invalid_mxid_characters(group_id.localpart):
+            raise SynapseError(
+                400,
+                "Group ID can only contain characters a-z, 0-9, or '=_-./'",
+            )
+
+        return group_id
+
+
+mxid_localpart_allowed_characters = set("_-./=" + string.ascii_lowercase + string.digits)
+
+
+def contains_invalid_mxid_characters(localpart):
+    """Check for characters not allowed in an mxid or groupid localpart
+
+    Args:
+        localpart (basestring): the localpart to be checked
+
+    Returns:
+        bool: True if there are any naughty characters
+    """
+    return any(c not in mxid_localpart_allowed_characters for c in localpart)
+
 
 class StreamToken(
     namedtuple("Token", (