Initialise user displayname from SAML2 data (#4272)

When we register a new user from SAML2 data, initialise their displayname
correctly.

6 files changed, 39 insertions, 15 deletions

diff --git a/changelog.d/4272.feature b/changelog.d/4272.feature
new file mode 100644
index 0000000000..7a8f286957
--- /dev/null
+++ b/changelog.d/4272.feature
@@ -0,0 +1 @@
+SAML2 authentication: Initialise user display name from SAML2 data
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index 0f87c4610e..ba39e67f6f 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -126,6 +126,7 @@ class RegistrationHandler(BaseHandler):
         make_guest=False,
         admin=False,
         threepid=None,
+        default_display_name=None,
     ):
         """Registers a new client on the server.
 
@@ -140,6 +141,8 @@ class RegistrationHandler(BaseHandler):
               since it offers no means of associating a device_id with the
               access_token. Instead you should call auth_handler.issue_access_token
               after registration.
+            default_display_name (unicode|None): if set, the new user's displayname
+              will be set to this. Defaults to 'localpart'.
         Returns:
             A tuple of (user_id, access_token).
         Raises:
@@ -169,6 +172,13 @@ class RegistrationHandler(BaseHandler):
             user = UserID(localpart, self.hs.hostname)
             user_id = user.to_string()
 
+            if was_guest:
+                # If the user was a guest then they already have a profile
+                default_display_name = None
+
+            elif default_display_name is None:
+                default_display_name = localpart
+
             token = None
             if generate_token:
                 token = self.macaroon_gen.generate_access_token(user_id)
@@ -178,10 +188,7 @@ class RegistrationHandler(BaseHandler):
                 password_hash=password_hash,
                 was_guest=was_guest,
                 make_guest=make_guest,
-                create_profile_with_localpart=(
-                    # If the user was a guest then they already have a profile
-                    None if was_guest else user.localpart
-                ),
+                create_profile_with_displayname=default_display_name,
                 admin=admin,
             )
 
@@ -203,13 +210,15 @@ class RegistrationHandler(BaseHandler):
                 yield self.check_user_id_not_appservice_exclusive(user_id)
                 if generate_token:
                     token = self.macaroon_gen.generate_access_token(user_id)
+                if default_display_name is None:
+                    default_display_name = localpart
                 try:
                     yield self.store.register(
                         user_id=user_id,
                         token=token,
                         password_hash=password_hash,
                         make_guest=make_guest,
-                        create_profile_with_localpart=user.localpart,
+                        create_profile_with_displayname=default_display_name,
                     )
                 except SynapseError:
                     # if user id is taken, just generate another
@@ -300,7 +309,7 @@ class RegistrationHandler(BaseHandler):
             user_id=user_id,
             password_hash="",
             appservice_id=service_id,
-            create_profile_with_localpart=user.localpart,
+            create_profile_with_displayname=user.localpart,
         )
         defer.returnValue(user_id)
 
@@ -478,7 +487,7 @@ class RegistrationHandler(BaseHandler):
                 user_id=user_id,
                 token=token,
                 password_hash=password_hash,
-                create_profile_with_localpart=user.localpart,
+                create_profile_with_displayname=user.localpart,
             )
         else:
             yield self._auth_handler.delete_access_tokens_for_user(user_id)
diff --git a/synapse/rest/client/v1/login.py b/synapse/rest/client/v1/login.py
index b7c5b58b01..e9d3032498 100644
--- a/synapse/rest/client/v1/login.py
+++ b/synapse/rest/client/v1/login.py
@@ -451,6 +451,7 @@ class SSOAuthHandler(object):
     @defer.inlineCallbacks
     def on_successful_auth(
         self, username, request, client_redirect_url,
+        user_display_name=None,
     ):
         """Called once the user has successfully authenticated with the SSO.
 
@@ -467,6 +468,9 @@ class SSOAuthHandler(object):
             client_redirect_url (unicode): the redirect_url the client gave us when
                 it first started the process.
 
+            user_display_name (unicode|None): if set, and we have to register a new user,
+                we will set their displayname to this.
+
         Returns:
             Deferred[none]: Completes once we have handled the request.
         """
@@ -478,6 +482,7 @@ class SSOAuthHandler(object):
                 yield self._registration_handler.register(
                     localpart=localpart,
                     generate_token=False,
+                    default_display_name=user_display_name,
                 )
             )
 
diff --git a/synapse/rest/saml2/response_resource.py b/synapse/rest/saml2/response_resource.py
index ad2ed157b5..69fb77b322 100644
--- a/synapse/rest/saml2/response_resource.py
+++ b/synapse/rest/saml2/response_resource.py
@@ -66,6 +66,9 @@ class SAML2ResponseResource(Resource):
             raise CodeMessageException(400, "uid not in SAML2 response")
 
         username = saml2_auth.ava["uid"][0]
+
+        displayName = saml2_auth.ava.get("displayName", [None])[0]
         return self._sso_auth_handler.on_successful_auth(
             username, request, relay_state,
+            user_display_name=displayName,
         )
diff --git a/synapse/storage/registration.py b/synapse/storage/registration.py
index 80d76bf9d7..3d55441e33 100644
--- a/synapse/storage/registration.py
+++ b/synapse/storage/registration.py
@@ -22,6 +22,7 @@ from twisted.internet import defer
 from synapse.api.errors import Codes, StoreError
 from synapse.storage import background_updates
 from synapse.storage._base import SQLBaseStore
+from synapse.types import UserID
 from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
 
 
@@ -167,7 +168,7 @@ class RegistrationStore(RegistrationWorkerStore,
 
     def register(self, user_id, token=None, password_hash=None,
                  was_guest=False, make_guest=False, appservice_id=None,
-                 create_profile_with_localpart=None, admin=False):
+                 create_profile_with_displayname=None, admin=False):
         """Attempts to register an account.
 
         Args:
@@ -181,8 +182,8 @@ class RegistrationStore(RegistrationWorkerStore,
             make_guest (boolean): True if the the new user should be guest,
                 false to add a regular user account.
             appservice_id (str): The ID of the appservice registering the user.
-            create_profile_with_localpart (str): Optionally create a profile for
-                the given localpart.
+            create_profile_with_displayname (unicode): Optionally create a profile for
+                the user, setting their displayname to the given value
         Raises:
             StoreError if the user_id could not be registered.
         """
@@ -195,7 +196,7 @@ class RegistrationStore(RegistrationWorkerStore,
             was_guest,
             make_guest,
             appservice_id,
-            create_profile_with_localpart,
+            create_profile_with_displayname,
             admin
         )
 
@@ -208,9 +209,11 @@ class RegistrationStore(RegistrationWorkerStore,
         was_guest,
         make_guest,
         appservice_id,
-        create_profile_with_localpart,
+        create_profile_with_displayname,
         admin,
     ):
+        user_id_obj = UserID.from_string(user_id)
+
         now = int(self.clock.time())
 
         next_id = self._access_tokens_id_gen.get_next()
@@ -273,12 +276,15 @@ class RegistrationStore(RegistrationWorkerStore,
                 (next_id, user_id, token,)
             )
 
-        if create_profile_with_localpart:
+        if create_profile_with_displayname:
             # set a default displayname serverside to avoid ugly race
             # between auto-joins and clients trying to set displaynames
+            #
+            # *obviously* the 'profiles' table uses localpart for user_id
+            # while everything else uses the full mxid.
             txn.execute(
                 "INSERT INTO profiles(user_id, displayname) VALUES (?,?)",
-                (create_profile_with_localpart, create_profile_with_localpart)
+                (user_id_obj.localpart, create_profile_with_displayname)
             )
 
         self._invalidate_cache_and_stream(
diff --git a/tests/storage/test_monthly_active_users.py b/tests/storage/test_monthly_active_users.py
index 8664bc3d54..9618d57463 100644
--- a/tests/storage/test_monthly_active_users.py
+++ b/tests/storage/test_monthly_active_users.py
@@ -149,7 +149,7 @@ class MonthlyActiveUsersTestCase(HomeserverTestCase):
 
     def test_populate_monthly_users_is_guest(self):
         # Test that guest users are not added to mau list
-        user_id = "user_id"
+        user_id = "@user_id:host"
         self.store.register(
             user_id=user_id, token="123", password_hash=None, make_guest=True
         )