This proposed upstream patch addresses CVE-2014-0006 and is tracked

under Launchpad bug 1265665. Although it's been addressed in 1.12.0,

the patch below is still not yet released for 1.10.0.

commit b2c61375b3255486adb2900922a894dc7dad3c6d

Author: Samuel Merritt <[email protected]>

Date:   Thu Jan 16 13:44:23 2014 +0100

    Use constant time comparison in tempURL

    Use constant time comparison when evaluating tempURL to avoid timing

    attacks (CVE-2014-0006). This is the havana backport of the master

    patch.

    Fixes bug 1265665

    Change-Id: I11e4ad83cc4077e52adf54a0bd0f9749294b2a48

diff --git a/swift/common/middleware/tempurl.py b/swift/common/middleware/tempurl.py

index ffc1431..ae2f4a1 100644

--- a/swift/common/middleware/tempurl.py

+++ b/swift/common/middleware/tempurl.py

@@ -98,7 +98,7 @@ from urlparse import parse_qs

 from swift.proxy.controllers.base import get_account_info

 from swift.common.swob import HeaderKeyDict

-from swift.common.utils import split_path

+from swift.common.utils import split_path, streq_const_time

 #: Default headers to remove from incoming requests. Simply a whitespace

@@ -267,17 +267,20 @@ class TempURL(object):

         if not keys:

             return self._invalid(env, start_response)

         if env['REQUEST_METHOD'] == 'HEAD':

-            hmac_vals = self._get_hmacs(env, temp_url_expires, keys,

-                                        request_method='GET')

-            if temp_url_sig not in hmac_vals:

-                hmac_vals = self._get_hmacs(env, temp_url_expires, keys,

-                                            request_method='PUT')

-                if temp_url_sig not in hmac_vals:

-                    return self._invalid(env, start_response)

+            hmac_vals = (self._get_hmacs(env, temp_url_expires, keys,

+                                         request_method='GET') +

+                         self._get_hmacs(env, temp_url_expires, keys,

+                                         request_method='PUT'))

         else:

             hmac_vals = self._get_hmacs(env, temp_url_expires, keys)

-            if temp_url_sig not in hmac_vals:

-                return self._invalid(env, start_response)

+

+        # While it's true that any() will short-circuit, this doesn't affect

+        # the timing-attack resistance since the only way this will

+        # short-circuit is when a valid signature is passed in.

+        is_valid_hmac = any(streq_const_time(temp_url_sig, h)

+                            for h in hmac_vals)

+        if not is_valid_hmac:

+            return self._invalid(env, start_response)

         self._clean_incoming_headers(env)

         env['swift.authorize'] = lambda req: None

         env['swift.authorize_override'] = True