From f2ec2be821b49ad565bdb92e44eabe9510cf5455 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timo=20K=C3=B6sters?= <timo@koesters.xyz>
Date: Wed, 3 Mar 2021 21:41:26 +0100
Subject: [PATCH] fix: don't always query aliases of appservices

only do so if the alias matches the regex in the registration file
---
 src/client_server/alias.rs | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/src/client_server/alias.rs b/src/client_server/alias.rs
index b8c16d96..0a8ad08d 100644
--- a/src/client_server/alias.rs
+++ b/src/client_server/alias.rs
@@ -1,5 +1,6 @@
 use super::State;
 use crate::{ConduitResult, Database, Error, Ruma};
+use regex::Regex;
 use ruma::{
     api::{
         appservice,
@@ -86,15 +87,23 @@ pub async fn get_alias_helper(
         Some(r) => room_id = Some(r),
         None => {
             for (_id, registration) in db.appservice.iter_all().filter_map(|r| r.ok()) {
-                if db
-                    .sending
-                    .send_appservice_request(
-                        &db.globals,
-                        registration,
-                        appservice::query::query_room_alias::v1::Request { room_alias },
-                    )
-                    .await
-                    .is_ok()
+                let aliases = registration
+                    .get("namespaces")
+                    .and_then(|ns| ns.get("aliases"))
+                    .and_then(|users| users.get("regex"))
+                    .and_then(|regex| regex.as_str())
+                    .and_then(|regex| Regex::new(regex).ok());
+
+                if aliases.map_or(false, |aliases| aliases.is_match(room_alias.as_str()))
+                    && db
+                        .sending
+                        .send_appservice_request(
+                            &db.globals,
+                            registration,
+                            appservice::query::query_room_alias::v1::Request { room_alias },
+                        )
+                        .await
+                        .is_ok()
                 {
                     room_id = Some(db.rooms.id_from_alias(&room_alias)?.ok_or_else(|| {
                         Error::bad_config("Appservice lied to us. Room does not exist.")