File python-3.4-CVE-2016-1000110-fix.patch of Package python3.3539

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File python-3.4-CVE-2016-1000110-fix.patch of Package python3.3539

# HG changeset patch
# User Senthil Kumaran <senthil@uthcode.com>
# Date 1469946874 25200
# Node ID 3c19023c9fec5a615c25598468b44fade89049ce
# Parent  17ec4d58c04634cd7d8cdd36d259be7c60bc8a61# Parent  95b09ccc8a3eda0a1c9e61b366e31be443f7a34c
[merge from 3.3] Prevent HTTPoxy attack (CVE-2016-1000110)

Ignore the HTTP_PROXY variable when REQUEST_METHOD environment is set, which
indicates that the script is in CGI mode.

Issue #27568 Reported and patch contributed by Rémi Rampin.

Index: Python-3.4.5/Doc/howto/urllib2.rst
===================================================================
--- Python-3.4.5.orig/Doc/howto/urllib2.rst
+++ Python-3.4.5/Doc/howto/urllib2.rst
@@ -538,6 +538,11 @@ setting up a `Basic Authentication`_ han
     through a proxy.  However, this can be enabled by extending urllib.request as
     shown in the recipe [#]_.
 
+.. note::
+
+   `HTTP_PROXY`` will be ignored if a variable ``REQUEST_METHOD`` is set; see
+   the documentation on :func:`~urllib.request.getproxies`.
+
 
 Sockets and Layers
 ==================
Index: Python-3.4.5/Doc/library/urllib.request.rst
===================================================================
--- Python-3.4.5.orig/Doc/library/urllib.request.rst
+++ Python-3.4.5/Doc/library/urllib.request.rst
@@ -168,6 +168,14 @@ The :mod:`urllib.request` module defines
    If both lowercase and uppercase environment variables exist (and disagree),
    lowercase is preferred.
 
+   .. note::
+
+      If the environment variable ``REQUEST_METHOD`` is set, which usually
+      indicates your script is running in a CGI environment, the environment
+      variable ``HTTP_PROXY`` (uppercase ``_PROXY``) will be ignored. This is
+      because that variable can be injected by a client using the "Proxy:" HTTP
+      header. If you need to use an HTTP proxy in a CGI environment use
+      ``ProxyHandler`` explicitly.
 
 The following classes are provided:
 
@@ -270,6 +278,11 @@ The following classes are provided:
 
    To disable autodetected proxy pass an empty dictionary.
 
+   .. note::
+
+      ``HTTP_PROXY`` will be ignored if a variable ``REQUEST_METHOD`` is set;
+      see the documentation on :func:`~urllib.request.getproxies`.
+
 
 .. class:: HTTPPasswordMgr()
 
Index: Python-3.4.5/Lib/test/test_urllib.py
===================================================================
--- Python-3.4.5.orig/Lib/test/test_urllib.py
+++ Python-3.4.5/Lib/test/test_urllib.py
@@ -224,6 +224,18 @@ class ProxyTests(unittest.TestCase):
         self.assertTrue(urllib.request.proxy_bypass_environment('anotherdomain.com:8888'))
         self.assertTrue(urllib.request.proxy_bypass_environment('newdomain.com:1234'))
 
+    def test_proxy_cgi_ignore(self):
+        try:
+            self.env.set('HTTP_PROXY', 'http://somewhere:3128')
+            proxies = urllib.request.getproxies_environment()
+            self.assertEqual('http://somewhere:3128', proxies['http'])
+            self.env.set('REQUEST_METHOD', 'GET')
+            proxies = urllib.request.getproxies_environment()
+            self.assertNotIn('http', proxies)
+        finally:
+            self.env.unset('REQUEST_METHOD')
+            self.env.unset('HTTP_PROXY')
+
 
 class ProxyTests_withOrderedEnv(unittest.TestCase):
 
@@ -260,6 +272,7 @@ class ProxyTests_withOrderedEnv(unittest
         proxies = urllib.request.getproxies_environment()
         self.assertEqual('http://somewhere:3128', proxies['http'])
 
+
 class urlopen_HttpTests(unittest.TestCase, FakeHTTPMixin, FakeFTPMixin):
     """Test urlopen() opening a fake http connection."""
 
Index: Python-3.4.5/Lib/urllib/request.py
===================================================================
--- Python-3.4.5.orig/Lib/urllib/request.py
+++ Python-3.4.5/Lib/urllib/request.py
@@ -2339,6 +2339,12 @@ def getproxies_environment():
         name = name.lower()
         if value and name[-6:] == '_proxy':
             proxies[name[:-6]] = value
+    # CVE-2016-1000110 - If we are running as CGI script, forget HTTP_PROXY
+    # (non-all-lowercase) as it may be set from the web server by a "Proxy:"
+    # header from the client
+    # If "proxy" is lowercase, it will still be used thanks to the next block
+    if 'REQUEST_METHOD' in os.environ:
+        proxies.pop('http', None)
     for name, value in os.environ.items():
         if name[-6:] == '_proxy':
             name = name.lower()
Index: Python-3.4.5/Misc/NEWS
===================================================================
--- Python-3.4.5.orig/Misc/NEWS
+++ Python-3.4.5/Misc/NEWS
@@ -7,6 +7,10 @@ What's New in Python 3.4.5?
 
 Release date: 2016-06-26
 
+- Issue #27568: Prevent HTTPoxy attack (CVE-2016-1000110). Ignore the
+  HTTP_PROXY variable when REQUEST_METHOD environment is set, which indicates
+  that the script is in CGI mode.
+
 Tests
 -----

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