diff --git a/docs/src/searx.botdetection.rst b/docs/src/searx.botdetection.rst index 04cb81dfd..1c3e12dad 100644 --- a/docs/src/searx.botdetection.rst +++ b/docs/src/searx.botdetection.rst @@ -53,6 +53,9 @@ Probe HTTP headers .. automodule:: searx.botdetection.http_user_agent :members: +.. automodule:: searx.botdetection.sec_fetch + :members: + .. _botdetection config: Config diff --git a/searx/botdetection/_helpers.py b/searx/botdetection/_helpers.py index 5387fe5cc..f3e20bca8 100644 --- a/searx/botdetection/_helpers.py +++ b/searx/botdetection/_helpers.py @@ -31,6 +31,9 @@ def dump_request(request: flask.Request): + " || Content-Length: %s" % request.headers.get('Content-Length') + " || Connection: %s" % request.headers.get('Connection') + " || User-Agent: %s" % request.headers.get('User-Agent') + + " || Sec-Fetch-Site: %s" % request.headers.get('Sec-Fetch-Site') + + " || Sec-Fetch-Mode: %s" % request.headers.get('Sec-Fetch-Mode') + + " || Sec-Fetch-Dest: %s" % request.headers.get('Sec-Fetch-Dest') ) diff --git a/searx/botdetection/http_sec_fetch.py b/searx/botdetection/http_sec_fetch.py new file mode 100644 index 000000000..9ece38540 --- /dev/null +++ b/searx/botdetection/http_sec_fetch.py @@ -0,0 +1,59 @@ +# SPDX-License-Identifier: AGPL-3.0-or-later +""" +Method ``http_sec_fetch`` +------------------------- + +The ``http_sec_fetch`` method protect resources from web attacks with `Fetch +Metadata`_. A request is filtered out in case of: + +- http header Sec-Fetch-Mode_ is invalid +- http header Sec-Fetch-Dest_ is invalid + +.. _Fetch Metadata: + https://developer.mozilla.org/en-US/docs/Glossary/Fetch_metadata_request_header + +.. Sec-Fetch-Dest: + https://developer.mozilla.org/en-US/docs/Web/API/Request/destination + +.. Sec-Fetch-Mode: + https://developer.mozilla.org/en-US/docs/Web/API/Request/mode + + +""" +# pylint: disable=unused-argument + +from __future__ import annotations +from ipaddress import ( + IPv4Network, + IPv6Network, +) + +import flask +import werkzeug + +from . import config +from ._helpers import logger + + +def filter_request( + network: IPv4Network | IPv6Network, + request: flask.Request, + cfg: config.Config, +) -> werkzeug.Response | None: + + val = request.headers.get("Sec-Fetch-Mode", "") + if val != "navigate": + logger.debug("invalid Sec-Fetch-Mode '%s'", val) + return flask.redirect(flask.url_for('index'), code=302) + + val = request.headers.get("Sec-Fetch-Site", "") + if val not in ('same-origin', 'same-site', 'none'): + logger.debug("invalid Sec-Fetch-Site '%s'", val) + flask.redirect(flask.url_for('index'), code=302) + + val = request.headers.get("Sec-Fetch-Dest", "") + if val != "document": + logger.debug("invalid Sec-Fetch-Dest '%s'", val) + flask.redirect(flask.url_for('index'), code=302) + + return None diff --git a/searx/limiter.py b/searx/limiter.py index 6c1c8894b..073ee0e93 100644 --- a/searx/limiter.py +++ b/searx/limiter.py @@ -111,6 +111,7 @@ from searx.botdetection import ( http_accept_encoding, http_accept_language, http_user_agent, + http_sec_fetch, ip_limit, ip_lists, get_network, @@ -178,16 +179,17 @@ def filter_request(request: flask.Request) -> werkzeug.Response | None: logger.error("BLOCK %s: matched BLOCKLIST - %s", network.compressed, msg) return flask.make_response(('IP is on BLOCKLIST - %s' % msg, 429)) - # methods applied on / + # methods applied on all requests for func in [ http_user_agent, ]: val = func.filter_request(network, request, cfg) if val is not None: + logger.debug(f"NOT OK ({func.__name__}): {network}: %s", dump_request(flask.request)) return val - # methods applied on /search + # methods applied on /search requests if request.path == '/search': @@ -196,12 +198,15 @@ def filter_request(request: flask.Request) -> werkzeug.Response | None: http_accept_encoding, http_accept_language, http_user_agent, + http_sec_fetch, ip_limit, ]: val = func.filter_request(network, request, cfg) if val is not None: + logger.debug(f"NOT OK ({func.__name__}): {network}: %s", dump_request(flask.request)) return val - logger.debug(f"OK {network}: %s", dump_request(flask.request)) + logger.debug(f"OK: {network}: %s", dump_request(flask.request)) + return None