[mod] limiter: trusted proxies (#4911)

Replaces `x_for` functionality with `trusted_proxies`. This allows defining
which IP / ranges to trust extracting the client IP address from X-Forwarded-For
and X-Real-IP headers.

We don't know if the proxy chain will give us the proper client
address (REMOTE_ADDR in the WSGI environment), so we rely on reading the headers
of the proxy before SearXNG (if there is one, in that case it must be added to
trusted_proxies) hoping it has done the proper checks. In case a proxy in the
chain does not check the client address correctly, integrity is compromised and
this should be fixed by whoever manages the proxy, not us.

Closes:

- https://github.com/searxng/searxng/issues/4940
- https://github.com/searxng/searxng/issues/4939
- https://github.com/searxng/searxng/issues/4907
- https://github.com/searxng/searxng/issues/3632
- https://github.com/searxng/searxng/issues/3191
- https://github.com/searxng/searxng/issues/1237

Related:

- https://github.com/searxng/searxng-docker/issues/386
- https://github.com/inetol-infrastructure/searxng-container/issues/81

1 files changed, 1 insertions, 3 deletions

diff --git a/searx/botdetection/http_sec_fetch.py b/searx/botdetection/http_sec_fetch.py
index f64ee4b2c..edead3bfa 100644
--- a/searx/botdetection/http_sec_fetch.py
+++ b/searx/botdetection/http_sec_fetch.py
@@ -32,8 +32,6 @@ import re
 import flask
 import werkzeug
 
-from searx.extended_types import SXNG_Request
-
 from . import config
 from ._helpers import logger
 
@@ -78,7 +76,7 @@ def is_browser_supported(user_agent: str) -> bool:
 
 def filter_request(
     network: IPv4Network | IPv6Network,
-    request: SXNG_Request,
+    request: flask.Request,
     cfg: config.Config,
 ) -> werkzeug.Response | None: