From 4dea4883e6c50d75f215a6b9bcbd95273f57c72d Mon Sep 17 00:00:00 2001
From: Florian Apolloner <florian@apolloner.eu>
Date: Mon, 30 Jul 2012 22:03:46 +0200
Subject: [PATCH] [1.3.x] Fixed a security issue in http redirects. Disclosure
 and new release forthcoming.

Backport of 4129201c3e0fa057c198bdefcb34686a23b4a93c from master.
---
 django/http/__init__.py                     | 25 ++++++++++++---------
 tests/regressiontests/httpwrappers/tests.py | 19 ++++++++++++++--
 2 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/django/http/__init__.py b/django/http/__init__.py
index 07e5a46797..74113b080a 100644
--- a/django/http/__init__.py
+++ b/django/http/__init__.py
@@ -4,7 +4,7 @@ import re
 import time
 from pprint import pformat
 from urllib import urlencode, quote
-from urlparse import urljoin
+from urlparse import urljoin, urlparse
 try:
     from cStringIO import StringIO
 except ImportError:
@@ -117,6 +117,7 @@ class CompatCookie(SimpleCookie):
         warnings.warn("CompatCookie is deprecated, use django.http.SimpleCookie instead.",
                       PendingDeprecationWarning)
 
+from django.core.exceptions import SuspiciousOperation
 from django.utils.datastructures import MultiValueDict, ImmutableList
 from django.utils.encoding import smart_str, iri_to_uri, force_unicode
 from django.utils.http import cookie_date
@@ -635,20 +636,22 @@ class HttpResponse(object):
             raise Exception("This %s instance cannot tell its position" % self.__class__)
         return sum([len(chunk) for chunk in self._container])
 
-class HttpResponseRedirect(HttpResponse):
+class HttpResponseRedirectBase(HttpResponse):
+    allowed_schemes = ['http', 'https', 'ftp']
+
+    def __init__(self, redirect_to):
+        super(HttpResponseRedirectBase, self).__init__()
+        parsed = urlparse(redirect_to)
+        if parsed.scheme and parsed.scheme not in self.allowed_schemes:
+            raise SuspiciousOperation("Unsafe redirect to URL with scheme '%s'" % parsed.scheme)
+        self['Location'] = iri_to_uri(redirect_to)
+
+class HttpResponseRedirect(HttpResponseRedirectBase):
     status_code = 302
 
-    def __init__(self, redirect_to):
-        super(HttpResponseRedirect, self).__init__()
-        self['Location'] = iri_to_uri(redirect_to)
-
-class HttpResponsePermanentRedirect(HttpResponse):
+class HttpResponsePermanentRedirect(HttpResponseRedirectBase):
     status_code = 301
 
-    def __init__(self, redirect_to):
-        super(HttpResponsePermanentRedirect, self).__init__()
-        self['Location'] = iri_to_uri(redirect_to)
-
 class HttpResponseNotModified(HttpResponse):
     status_code = 304
 
diff --git a/tests/regressiontests/httpwrappers/tests.py b/tests/regressiontests/httpwrappers/tests.py
index 6aabfe655e..9a9b73edee 100644
--- a/tests/regressiontests/httpwrappers/tests.py
+++ b/tests/regressiontests/httpwrappers/tests.py
@@ -1,8 +1,11 @@
 import copy
 import pickle
 
-from django.http import (QueryDict, HttpResponse, SimpleCookie, BadHeaderError,
-        parse_cookie)
+from django.core.exceptions import SuspiciousOperation
+from django.http import (QueryDict, HttpResponse, HttpResponseRedirect,
+                         HttpResponsePermanentRedirect,
+                         SimpleCookie, BadHeaderError,
+                         parse_cookie)
 from django.utils import unittest
 
 class QueryDictTests(unittest.TestCase):
@@ -243,6 +246,18 @@ class HttpResponseTests(unittest.TestCase):
         self.assertRaises(BadHeaderError, r.__setitem__, 'test\rstr', 'test')
         self.assertRaises(BadHeaderError, r.__setitem__, 'test\nstr', 'test')
 
+    def test_unsafe_redirects(self):
+        bad_urls = [
+            'data:text/html,<script>window.alert("xss")</script>',
+            'mailto:test@example.com',
+            'file:///etc/passwd',
+        ]
+        for url in bad_urls:
+            self.assertRaises(SuspiciousOperation,
+                              HttpResponseRedirect, url)
+            self.assertRaises(SuspiciousOperation,
+                              HttpResponsePermanentRedirect, url)
+
 class CookieTests(unittest.TestCase):
     def test_encode(self):
         """