Upstream patch for bug 1300274.

Fixed in Havana 2013.2.4, Icehouse 2014.1

From e364ba5b12de8e4c11bd80bcca903f9615dcfc2e Mon Sep 17 00:00:00 2001
From: Florent Flament <[email protected]>
Date: Tue, 1 Apr 2014 12:48:22 +0000
Subject: Sanitizes authentication methods received in requests.

When a user authenticates against Identity V3 API, he can specify
multiple authentication methods. This patch removes duplicates, which
could have been used to achieve DoS attacks.

Closes-Bug: 1300274
(cherry picked from commit ef868ad92c00e23a4a5e9eb71e3e0bf5ae2fff0c)
Cherry-pick from https://review.openstack.org/#/c/84425/

Change-Id: I6e60324309baa094a5e54b012fb0fc528fea72ab

--- keystone-2013.1.4/keystone/auth/controllers.py.orig	2014-04-10 14:46:27.890585026 -0600
+++ keystone-2013.1.4/keystone/auth/controllers.py	2014-04-10 14:47:53.783687911 -0600
@@ -228,7 +228,13 @@
         :returns: list of auth method names
 
         """
-        return self.auth['identity']['methods']
+        # Sanitizes methods received in request's body
+        # Filters out duplicates, while keeping elements' order.
+        method_names = []
+        for method in self.auth['identity']['methods']:
+            if method not in method_names:
+                method_names.append(method)
+        return method_names
 
     def get_method_data(self, method):
         """ Get the auth method payload.
--- keystone-2013.1.4/tests/test_v3_auth.py.orig	2014-04-10 14:50:45.929495618 -0600
+++ keystone-2013.1.4/tests/test_v3_auth.py	2014-04-10 14:50:48.764440233 -0600
@@ -83,6 +83,17 @@
                           None,
                           auth_data)
 
+    def test_get_method_names_duplicates(self):
+        auth_data = self.build_authentication_request(
+            token='test',
+            user_id='test',
+            password='test')['auth']
+        auth_data['identity']['methods'] = ['password', 'token',
+                                            'password', 'password']
+        context = None
+        auth_info = auth.controllers.AuthInfo(context, auth_data)
+        self.assertEqual(auth_info.get_method_names(),
+                         ['password', 'token'])
 
 class TestTokenAPIs(test_v3.RestfulTestCase):
     def setUp(self):