searxng/searx/botdetection/http_user_agent.py
Markus Heiser b8c7c2c9aa [mod] botdetection - improve ip_limit and link_token methods
- counting requests in LONG_WINDOW and BURST_WINDOW is not needed when the
  request is validated by the link_token method [1]

- renew a ping-key on validation [2], this is needed for infinite scrolling,
  where no new token (CSS) is loaded. / this does not fix the BURST_MAX issue in
  the vanilla limiter

- normalize the counter names of the ip_limit method to 'ip_limit.*'

- just integrate the ip_limit method straight forward in the limiter plugin /
  non intermediate code --> ip_limit now returns None or a werkzeug.Response
  object that can be passed by the plugin to the flask application / non
  intermediate code that returns a tuple

[1] https://github.com/searxng/searxng/pull/2357#issuecomment-1566113277
[2] https://github.com/searxng/searxng/pull/2357#discussion_r1208542206
[3] https://github.com/searxng/searxng/pull/2357#issuecomment-1566125979

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
2023-06-01 14:38:53 +02:00

58 lines
1.8 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-or-later
# lint: pylint
"""
Method ``http_user_agent``
--------------------------
The ``http_user_agent`` method evaluates a request as the request of a bot if
the User-Agent_ header is unset or matches the regular expression
:py:obj:`USER_AGENT`.
.. _User-Agent:
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/User-Agent
"""
# pylint: disable=unused-argument
from typing import Optional
import re
import flask
import werkzeug
from searx.tools import config
from ._helpers import too_many_requests
USER_AGENT = (
r'('
+ r'unknown'
+ r'|[Cc][Uu][Rr][Ll]|[wW]get|Scrapy|splash|JavaFX|FeedFetcher|python-requests|Go-http-client|Java|Jakarta|okhttp'
+ r'|HttpClient|Jersey|Python|libwww-perl|Ruby|SynHttpClient|UniversalFeedParser|Googlebot|GoogleImageProxy'
+ r'|bingbot|Baiduspider|yacybot|YandexMobileBot|YandexBot|Yahoo! Slurp|MJ12bot|AhrefsBot|archive.org_bot|msnbot'
+ r'|MJ12bot|SeznamBot|linkdexbot|Netvibes|SMTBot|zgrab|James BOT|Sogou|Abonti|Pixray|Spinn3r|SemrushBot|Exabot'
+ r'|ZmEu|BLEXBot|bitlybot'
# unmaintained Farside instances
+ r'|'
+ re.escape(r'Mozilla/5.0 (compatible; Farside/0.1.0; +https://farside.link)')
# other bots and client to block
+ '|.*PetalBot.*'
+ r')'
)
"""Regular expression that matches to User-Agent_ from known *bots*"""
_regexp = None
def regexp_user_agent():
global _regexp # pylint: disable=global-statement
if not _regexp:
_regexp = re.compile(USER_AGENT)
return _regexp
def filter_request(request: flask.Request, cfg: config.Config) -> Optional[werkzeug.Response]:
user_agent = request.headers.get('User-Agent', 'unknown')
if regexp_user_agent().match(user_agent):
return too_many_requests(request, f"bot detected, HTTP header User-Agent: {user_agent}")
return None