149 lines
5.2 KiB
Python
149 lines
5.2 KiB
Python
# Copyright (c) 2012 OpenStack Foundation
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
|
|
# implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
'''
|
|
Created on February 27, 2012
|
|
|
|
A filter that disallows any paths that contain defined forbidden characters or
|
|
that exceed a defined length.
|
|
|
|
Place early in the proxy-server pipeline after the left-most occurrence of the
|
|
``proxy-logging`` middleware (if present) and before the final
|
|
``proxy-logging`` middleware (if present) or the ``proxy-serer`` app itself,
|
|
e.g.::
|
|
|
|
[pipeline:main]
|
|
pipeline = catch_errors healthcheck proxy-logging name_check cache \
|
|
ratelimit tempauth sos proxy-logging proxy-server
|
|
|
|
[filter:name_check]
|
|
use = egg:swift#name_check
|
|
forbidden_chars = '"`<>
|
|
maximum_length = 255
|
|
|
|
There are default settings for forbidden_chars (FORBIDDEN_CHARS) and
|
|
maximum_length (MAX_LENGTH)
|
|
|
|
The filter returns HTTPBadRequest if path is invalid.
|
|
|
|
@author: eamonn-otoole
|
|
'''
|
|
|
|
import re
|
|
from swift.common.utils import get_logger, register_swift_info
|
|
|
|
from swift.common.swob import Request, HTTPBadRequest
|
|
|
|
|
|
FORBIDDEN_CHARS = "\'\"`<>"
|
|
MAX_LENGTH = 255
|
|
FORBIDDEN_REGEXP = r"/\./|/\.\./|/\.$|/\.\.$"
|
|
|
|
|
|
class NameCheckMiddleware(object):
|
|
|
|
def __init__(self, app, conf):
|
|
self.app = app
|
|
self.conf = conf
|
|
self.forbidden_chars = self.conf.get('forbidden_chars',
|
|
FORBIDDEN_CHARS)
|
|
self.maximum_length = int(self.conf.get('maximum_length', MAX_LENGTH))
|
|
self.forbidden_regexp = self.conf.get('forbidden_regexp',
|
|
FORBIDDEN_REGEXP)
|
|
if self.forbidden_regexp:
|
|
self.forbidden_regexp_compiled = re.compile(self.forbidden_regexp)
|
|
else:
|
|
self.forbidden_regexp_compiled = None
|
|
self.logger = get_logger(self.conf, log_route='name_check')
|
|
|
|
self.register_info()
|
|
|
|
def register_info(self):
|
|
register_swift_info('name_check',
|
|
forbidden_chars=self.forbidden_chars,
|
|
maximum_length=self.maximum_length,
|
|
forbidden_regexp=self.forbidden_regexp
|
|
)
|
|
|
|
def check_character(self, req):
|
|
'''
|
|
Checks req.path for any forbidden characters
|
|
Returns True if there are any forbidden characters
|
|
Returns False if there aren't any forbidden characters
|
|
'''
|
|
self.logger.debug("name_check: path %s" % req.path)
|
|
self.logger.debug("name_check: self.forbidden_chars %s" %
|
|
self.forbidden_chars)
|
|
|
|
return any((c in req.path_info) for c in self.forbidden_chars)
|
|
|
|
def check_length(self, req):
|
|
'''
|
|
Checks that req.path doesn't exceed the defined maximum length
|
|
Returns True if the length exceeds the maximum
|
|
Returns False if the length is <= the maximum
|
|
'''
|
|
length = len(req.path_info)
|
|
return length > self.maximum_length
|
|
|
|
def check_regexp(self, req):
|
|
'''
|
|
Checks that req.path doesn't contain a substring matching regexps.
|
|
Returns True if there are any forbidden substring
|
|
Returns False if there aren't any forbidden substring
|
|
'''
|
|
if self.forbidden_regexp_compiled is None:
|
|
return False
|
|
|
|
self.logger.debug("name_check: path %s" % req.path)
|
|
self.logger.debug("name_check: self.forbidden_regexp %s" %
|
|
self.forbidden_regexp)
|
|
|
|
match = self.forbidden_regexp_compiled.search(req.path_info)
|
|
return (match is not None)
|
|
|
|
def __call__(self, env, start_response):
|
|
req = Request(env)
|
|
|
|
if self.check_character(req):
|
|
return HTTPBadRequest(
|
|
request=req,
|
|
body=("Object/Container/Account name contains forbidden "
|
|
"chars from %s"
|
|
% self.forbidden_chars))(env, start_response)
|
|
elif self.check_length(req):
|
|
return HTTPBadRequest(
|
|
request=req,
|
|
body=("Object/Container/Account name longer than the "
|
|
"allowed maximum "
|
|
"%s" % self.maximum_length))(env, start_response)
|
|
elif self.check_regexp(req):
|
|
return HTTPBadRequest(
|
|
request=req,
|
|
body=("Object/Container/Account name contains a forbidden "
|
|
"substring from regular expression %s"
|
|
% self.forbidden_regexp))(env, start_response)
|
|
else:
|
|
# Pass on to downstream WSGI component
|
|
return self.app(env, start_response)
|
|
|
|
|
|
def filter_factory(global_conf, **local_conf):
|
|
conf = global_conf.copy()
|
|
conf.update(local_conf)
|
|
|
|
def name_check_filter(app):
|
|
return NameCheckMiddleware(app, conf)
|
|
return name_check_filter
|