Add support for enabling encryption by default

mautrix_telegram/matrix.py

@@ -20,7 +20,8 @@ from mautrix.types import (Event, EventType, RoomID, UserID, EventID, ReceiptEve
                            ReceiptEventContent, PresenceEvent, PresenceState, TypingEvent,
                            MessageEvent, StateEvent, RedactionEvent, RoomNameStateEventContent,
                            RoomAvatarStateEventContent, RoomTopicStateEventContent,
-                           MemberStateEventContent, EncryptedEvent)
+                           MemberStateEventContent, EncryptedEvent, TextMessageEventContent,
+                           MessageType)
 from mautrix.errors import MatrixError
 
 from . import user as u, portal as po, puppet as pu, commands as com
@@ -38,7 +39,7 @@ except ImportError:
     EVENT_TIME = None
 
 try:
-    from .e2ee import EncryptionManager
+    from mautrix.bridge.e2ee import EncryptionManager
 except ImportError:
     EncryptionManager = None
 
@@ -57,10 +58,15 @@ class MatrixHandler(BaseMatrixHandler):
                                             command_processor=com.CommandProcessor(context))
         self.e2ee = None
         if self.config["bridge.encryption.allow"]:
-            if EncryptionManager:
-                self.e2ee = EncryptionManager(context)
+            if not EncryptionManager:
+                self.log.error("Encryption enabled in config, but dependencies not installed.")
+            elif not self.config["bridge.login_shared_secret"]:
+                self.log.warning("Encryption enabled in config, but login_shared_secret not set.")
             else:
-                self.log.warning("Encryption enabled in config, but dependencies not installed.")
+                self.e2ee = EncryptionManager(
+                    bot_mxid=self.az.bot_mxid,
+                    login_shared_secret=self.config["bridge.login_shared_secret"],
+                    homeserver_address=self.config["homeserver.address"], loop=context.loop)
         self.bot = context.bot
         self.previously_typing = {}
 
@@ -121,14 +127,50 @@ class MatrixHandler(BaseMatrixHandler):
                 except MatrixError:
                     pass
             portal.mxid = room_id
+            e2be_ok = None
+            if self.config["bridge.encryption.default"] and self.e2ee:
+                e2be_ok = await self._enable_dm_encryption(portal)
             portal.save()
             inviter.register_portal(portal)
-            await intent.send_notice(room_id, "Portal to private chat created.")
+            if e2be_ok is True:
+                evt_type, content = await self.e2ee.encrypt(
+                    room_id, EventType.ROOM_MESSAGE,
+                    TextMessageEventContent(msgtype=MessageType.NOTICE,
+                                            body="Portal to private chat created and end-to-bridge"
+                                                 " encryption enabled."))
+                await intent.send_message_event(room_id, evt_type, content)
+            else:
+                message = "Portal to private chat created."
+                if e2be_ok is False:
+                    message += "\n\nWarning: Failed to enable end-to-bridge encryption"
+                await intent.send_notice(room_id, message)
         else:
             await intent.join_room(room_id)
             await intent.send_notice(room_id, "This puppet will remain inactive until a "
                                               "Telegram chat is created for this room.")
 
+    async def _enable_dm_encryption(self, portal: po.Portal) -> bool:
+        try:
+            await portal.main_intent.invite_user(portal.mxid, self.az.bot_mxid)
+            await self.az.intent.join_room_by_id(portal.mxid)
+            await portal.main_intent.send_state_event(portal.mxid, EventType.ROOM_ENCRYPTION, {
+                "algorithm": "m.megolm.v1.aes-sha2"
+            })
+            # TODO feed info about room to matrix-nio
+        except Exception:
+            self.log.warning(f"Failed to enable end-to-bridge encryption in {portal.mxid}",
+                             exc_info=True)
+            return False
+
+        try:
+            puppet = pu.Puppet.get(portal.tgid)
+            await portal.main_intent.set_room_name(portal.mxid, puppet.displayname)
+        except Exception:
+            self.log.warning(f"Failed to set room name for {portal.mxid}", exc_info=True)
+
+        portal.encrypted = True
+        return True
+
     async def send_welcome_message(self, room_id: RoomID, inviter: 'u.User') -> None:
         try:
             is_management = len(await self.az.intent.get_room_members(room_id)) == 2
@@ -173,7 +215,7 @@ class MatrixHandler(BaseMatrixHandler):
                                                "messages for unauthenticated users.")
             return
 
-        self.log.debug(f"{user} joined {room_id}")
+        self.log.debug(f"{user.mxid} joined {room_id}")
         if await user.is_logged_in() or portal.has_bot:
             await portal.join_matrix(user, event_id)