Use constant time comparison in tempURL

Use constant time comparison when evaluating tempURL to avoid timing
attacks (CVE-2014-0006). This is the grizzly backport of the master
patch.

Fixes bug 1265665

Change-Id: I11e4ad83cc4077e52adf54a0bd0f9749294b2a48
This commit is contained in:
Samuel Merritt 2014-01-16 13:45:52 +01:00 committed by Thierry Carrez
parent 1f4ec235cd
commit c0eed792a2
1 changed files with 4 additions and 3 deletions

View File

@ -98,6 +98,7 @@ from urlparse import parse_qs
from swift.common.wsgi import make_pre_authed_env
from swift.common.http import HTTP_UNAUTHORIZED
from swift.common.utils import streq_const_time
#: Default headers to remove from incoming requests. Simply a whitespace
@ -248,14 +249,14 @@ class TempURL(object):
if env['REQUEST_METHOD'] == 'HEAD':
hmac_val = self._get_hmac(env, temp_url_expires, key,
request_method='GET')
if temp_url_sig != hmac_val:
if not streq_const_time(temp_url_sig, hmac_val):
hmac_val = self._get_hmac(env, temp_url_expires, key,
request_method='PUT')
if temp_url_sig != hmac_val:
if not streq_const_time(temp_url_sig, hmac_val):
return self._invalid(env, start_response)
else:
hmac_val = self._get_hmac(env, temp_url_expires, key)
if temp_url_sig != hmac_val:
if not streq_const_time(temp_url_sig, hmac_val):
return self._invalid(env, start_response)
self._clean_incoming_headers(env)
env['swift.authorize'] = lambda req: None