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[1.7.x] Dropped fix_IE_for_vary/attach.

This is a security fix. Disclosure following shortly.
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aaugustin authored and apollo13 committed May 14, 2014
1 parent 50f228a commit 7fef18ba9e5a8b47bc24b5bb259c8bf3d3879f2a
Showing with 2 additions and 106 deletions.
  1. +0 −2 django/core/handlers/
  2. +2 −3 django/http/
  3. +0 −55 django/http/
  4. +0 −46 tests/utils_tests/
@@ -23,8 +23,6 @@ class BaseHandler(object):
response_fixes = [

def __init__(self):
@@ -6,8 +6,7 @@
HttpResponseNotModified, HttpResponseBadRequest, HttpResponseForbidden,
HttpResponseNotFound, HttpResponseNotAllowed, HttpResponseGone,
HttpResponseServerError, Http404, BadHeaderError, JsonResponse)
from django.http.utils import (fix_location_header,
conditional_content_removal, fix_IE_for_attach, fix_IE_for_vary)
from django.http.utils import fix_location_header, conditional_content_removal

__all__ = [
'SimpleCookie', 'parse_cookie', 'HttpRequest', 'QueryDict',
@@ -17,5 +16,5 @@
'HttpResponseBadRequest', 'HttpResponseForbidden', 'HttpResponseNotFound',
'HttpResponseNotAllowed', 'HttpResponseGone', 'HttpResponseServerError',
'Http404', 'BadHeaderError', 'fix_location_header', 'JsonResponse',
'conditional_content_removal', 'fix_IE_for_attach', 'fix_IE_for_vary',
@@ -39,58 +39,3 @@ def conditional_content_removal(request, response):
response.content = b''
return response

def fix_IE_for_attach(request, response):
This function will prevent Django from serving a Content-Disposition header
while expecting the browser to cache it (only when the browser is IE). This
leads to IE not allowing the client to download.
useragent = request.META.get('HTTP_USER_AGENT', '').upper()
if 'MSIE' not in useragent and 'CHROMEFRAME' not in useragent:
return response

offending_headers = ('no-cache', 'no-store')
if response.has_header('Content-Disposition'):
del response['Pragma']
except KeyError:
if response.has_header('Cache-Control'):
cache_control_values = [value.strip() for value in
if value.strip().lower() not in offending_headers]

if not len(cache_control_values):
del response['Cache-Control']
response['Cache-Control'] = ', '.join(cache_control_values)

return response

def fix_IE_for_vary(request, response):
This function will fix the bug reported at
by clearing the Vary header whenever the mime-type is not safe
enough for Internet Explorer to handle. Poor thing.
useragent = request.META.get('HTTP_USER_AGENT', '').upper()
if 'MSIE' not in useragent and 'CHROMEFRAME' not in useragent:
return response

# These mime-types that are decreed "Vary-safe" for IE:
safe_mime_types = ('text/html', 'text/plain', 'text/sgml')

# The first part of the Content-Type field will be the MIME type,
# everything after ';', such as character-set, can be ignored.
mime_type = response.get('Content-Type', '').partition(';')[0]
if mime_type not in safe_mime_types:
del response['Vary']
except KeyError:

return response
@@ -2,8 +2,6 @@
import sys
import unittest

from django.http import HttpResponse, utils
from django.test import RequestFactory
from django.utils.datastructures import MultiValueDict
from django.utils import http
from django.utils import six
@@ -67,50 +65,6 @@ def test_urlencode(self):
self.assertTrue(result in acceptable_results)

def test_fix_IE_for_vary(self):
Regression for #16632.
`fix_IE_for_vary` shouldn't crash when there's no Content-Type header.

# functions to generate responses
def response_with_unsafe_content_type():
r = HttpResponse(content_type="text/unsafe")
r['Vary'] = 'Cookie'
return r

def no_content_response_with_unsafe_content_type():
# 'Content-Type' always defaulted, so delete it
r = response_with_unsafe_content_type()
del r['Content-Type']
return r

# request with & without IE user agent
rf = RequestFactory()
request = rf.get('/')
ie_request = rf.get('/', HTTP_USER_AGENT='MSIE')

# not IE, unsafe_content_type
response = response_with_unsafe_content_type()
utils.fix_IE_for_vary(request, response)
self.assertTrue('Vary' in response)

# IE, unsafe_content_type
response = response_with_unsafe_content_type()
utils.fix_IE_for_vary(ie_request, response)
self.assertFalse('Vary' in response)

# not IE, no_content
response = no_content_response_with_unsafe_content_type()
utils.fix_IE_for_vary(request, response)
self.assertTrue('Vary' in response)

# IE, no_content
response = no_content_response_with_unsafe_content_type()
utils.fix_IE_for_vary(ie_request, response)
self.assertFalse('Vary' in response)

def test_base36(self):
# reciprocity works
for n in [0, 1, 1000, 1000000]:

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