ERP5Type/patches: use the first entry of HTTP_X_FORWARDED_FOR as the source IP address.

This functionality is enabled only if 'trusted-proxies' configuration
value is ('0.0.0.0',) by putting the following in zope.conf :

trusted-proxy 0.0.0.0

product/ERP5Type/patches/HTTPRequest.py

 # -*- coding: utf-8 -*-
 
-from ZPublisher.HTTPRequest import HTTPRequest
+from ZPublisher.HTTPRequest import HTTPRequest, sane_environment
+import ZPublisher.HTTPRequest
 import sys
 import weakref
 import thread
 
 HTTPRequest__init__ = HTTPRequest.__init__
-def __init__(self, *args, **kw):
-  HTTPRequest__init__(self, *args, **kw)
+def __init__(self, stdin, environ, response, clean=0):
+  if ZPublisher.HTTPRequest.trusted_proxies == ('0.0.0.0',): # Magic value to enable this functionality
+    # Frontend-facing proxy is responsible for sanitising
+    # HTTP_X_FORWARDED_FOR, and only trusted accesses should bypass
+    # that proxy. So trust first entry.
+    forwarded_for = (
+      sane_environment(environ)
+      if not clean else
+      environ
+    ).get('HTTP_X_FORWARDED_FOR', '').split(',', 1)[0].strip()
+  else:
+    forwarded_for = None
+
+  HTTPRequest__init__(self, stdin=stdin, environ=environ, response=response, clean=clean)
 
   import erp5.component
   erp5.component.ref_manager.add_request(self)
 
+  if forwarded_for:
+    self._client_addr = forwarded_for
+
 HTTPRequest.__init__ = __init__

product/ERP5Type/patches/http_server.py

@@ -21,23 +21,23 @@
 
 
 from ZServer.medusa.http_server import http_request
-from ZPublisher.HTTPRequest import trusted_proxies
+import ZPublisher.HTTPRequest
 import string
 import base64
 import time
 from urllib import quote
 
 def log (self, bytes):
-    # The purpose of this patch is to emit original IP addresses in Z2.log
-    # even when a reverse proxy is used. A similar thing is implemented
-    # in the ZPublisher, but not in the ZServer.
+    addr = self.channel.addr[0]
+    # Frontend-facing proxy is responsible for sanitising
+    # HTTP_X_FORWARDED_FOR, and only trusted accesses should bypass
+    # that proxy. So trust first entry.
     #
     # <patch>
-    addr = self.channel.addr[0]
-    if trusted_proxies and addr in trusted_proxies:
-        original_addr = self.get_header('x-forwarded-for')
-        if original_addr:
-            addr = original_addr.split(', ')[0]
+    if ZPublisher.HTTPRequest.trusted_proxies == ('0.0.0.0',): # Magic value to enable this functionality
+      forwarded_for = (self.get_header('x-forwarded-for') or '').split(',', 1)[0].strip()
+      if forwarded_for:
+        addr = forwarded_for
     # </patch>
 
     user_agent=self.get_header('user-agent')

product/ERP5Type/tests/testERP5Type.py

@@ -33,6 +33,8 @@ except ImportError: # BBB: ZODB < 4
 import unittest
 import sys
 import mock
+import os
+import requests
 
 import transaction
 from random import randint
@@ -53,6 +55,7 @@ from AccessControl.ZopeGuards import guarded_getattr, guarded_hasattr
 from Products.ERP5Type.tests.utils import createZODBPythonScript
 from Products.ERP5Type.tests.utils import removeZODBPythonScript
 from Products.ERP5Type import Permissions
+from Products.ERP5Type.tests.runUnitTest import log_directory
 
 class PropertySheetTestCase(ERP5TypeTestCase):
   """Base test case class for property sheets tests.
@@ -3317,6 +3320,79 @@ return [
           '<Organisation at /%s/organisation_module/organisation_id>' % self.portal.getId(),
           repr(document))
 
+    def test_request_with_x_forwarded_for(self):
+      script_container = self.portal.portal_skins.custom
+      script_id = 'ERP5Site_getClientAddr'
+      createZODBPythonScript(script_container, script_id, '', 'return context.REQUEST.getClientAddr()')
+      self.commit()
+      z2_log_path = os.path.join(log_directory, 'Z2.log')
+      import ZPublisher.HTTPRequest
+
+      # test without configuration
+      ZPublisher.HTTPRequest.trusted_proxies = []
+      response = requests.get(
+        '%s/%s' % (self.portal.absolute_url(), script_id),
+        headers={'X-Forwarded-For': '1.2.3.4'},
+      )
+      self.assertNotEqual(response.text, '1.2.3.4')
+      f = open(z2_log_path, 'rb')
+      f.seek(-256, os.SEEK_END) # Assumes last line is not longer than 256 chars (it should be about 130)
+      last_line = f.readlines()[-1]
+      f.close()
+      self.assertFalse(last_line.startswith('1.2.3.4 - '), last_line)
+      response = requests.get(
+        '%s/%s' % (self.portal.absolute_url(), script_id),
+        headers={'X-Forwarded-For': '1.2.3.4, 5.6.7.8'},
+      )
+      self.assertNotEqual(response.text, '1.2.3.4')
+      self.assertNotEqual(response.text, '5.6.7.8')
+      f = open(z2_log_path, 'rb')
+      f.seek(-256, os.SEEK_END)
+      last_line = f.readlines()[-1]
+      f.close()
+      self.assertFalse(last_line.startswith('1.2.3.4 - '), last_line)
+      self.assertFalse(last_line.startswith('5.6.7.8 - '), last_line)
+      response = requests.get(
+        '%s/%s' % (self.portal.absolute_url(), script_id),
+      )
+      self.assertNotEqual(response.text, '1.2.3.4')
+      f = open(z2_log_path, 'rb')
+      f.seek(-256, os.SEEK_END)
+      last_line = f.readlines()[-1]
+      f.close()
+      self.assertFalse(last_line.startswith('1.2.3.4 - '), last_line)
+
+      # test with configuration
+      ZPublisher.HTTPRequest.trusted_proxies = ('0.0.0.0',)
+      response = requests.get(
+        '%s/%s' % (self.portal.absolute_url(), script_id),
+        headers={'X-Forwarded-For': '1.2.3.4'},
+      )
+      self.assertEqual(response.text, '1.2.3.4')
+      f = open(z2_log_path, 'rb')
+      f.seek(-256, os.SEEK_END)
+      last_line = f.readlines()[-1]
+      f.close()
+      self.assertTrue(last_line.startswith('1.2.3.4 - '), last_line)
+      response = requests.get(
+        '%s/%s' % (self.portal.absolute_url(), script_id),
+        headers={'X-Forwarded-For': '1.2.3.4, 5.6.7.8'},
+      )
+      self.assertEqual(response.text, '1.2.3.4')
+      f = open(z2_log_path, 'rb')
+      f.seek(-256, os.SEEK_END)
+      last_line = f.readlines()[-1]
+      f.close()
+      self.assertTrue(last_line.startswith('1.2.3.4 - '), last_line)
+      response = requests.get(
+        '%s/%s' % (self.portal.absolute_url(), script_id),
+      )
+      self.assertNotEqual(response.text, '1.2.3.4')
+      f = open(z2_log_path, 'rb')
+      f.seek(-256, os.SEEK_END)
+      last_line = f.readlines()[-1]
+      f.close()
+      self.assertFalse(last_line.startswith('1.2.3.4 - '), last_line)
 
 class TestAccessControl(ERP5TypeTestCase):
   # Isolate test in a dedicaced class in order not to break other tests