Extended Embargo feature to support site access restriction and ip network

cms/envs/common.py

@@ -88,6 +88,9 @@ FEATURES = {
     # Toggles embargo functionality
     'EMBARGO': False,
 
+    # Toggle embargo site functionality
+    'EMBARGO_SITE': False,
+
     # Turn on/off Microsites feature
     'USE_MICROSITES': False,
 

common/djangoapps/embargo/forms.py

@@ -7,7 +7,7 @@ from django import forms
 from embargo.models import EmbargoedCourse, EmbargoedState, IPFilter
 from embargo.fixtures.country_codes import COUNTRY_CODES
 
-import socket
+import ipaddr
 
 from xmodule.modulestore.django import modulestore
 
@@ -76,21 +76,12 @@ class IPFilterForm(forms.ModelForm):  # pylint: disable=incomplete-protocol
     class Meta:  # pylint: disable=missing-docstring
         model = IPFilter
 
-    def _is_valid_ipv4(self, address):
-        """Whether or not address is a valid ipv4 address"""
+    def _is_valid_ip(self, address):
+        """Whether or not address is a valid ipv4 address or ipv6 address"""
         try:
-            # Is this an ipv4 address?
-            socket.inet_pton(socket.AF_INET, address)
-        except socket.error:
-            return False
-        return True
-
-    def _is_valid_ipv6(self, address):
-        """Whether or not address is a valid ipv6 address"""
-        try:
-            # Is this an ipv6 address?
-            socket.inet_pton(socket.AF_INET6, address)
-        except socket.error:
+            # Is this an valid ip address?
+            ipaddr.IPNetwork(address)
+        except ValueError:
             return False
         return True
 
@@ -105,7 +96,7 @@ class IPFilterForm(forms.ModelForm):  # pylint: disable=incomplete-protocol
         error_addresses = []
         for addr in addresses.split(','):
             address = addr.strip()
-            if not (self._is_valid_ipv4(address) or self._is_valid_ipv6(address)):
+            if not self._is_valid_ip(address):
                 error_addresses.append(address)
         if error_addresses:
             msg = 'Invalid IP Address(es): {0}'.format(error_addresses)

common/djangoapps/embargo/middleware.py

-"""
-Middleware for embargoing courses.
+"""Middleware for embargoing site and courses.
 
 IMPORTANT NOTE: This code WILL NOT WORK if you have a misconfigured proxy
 server.  If you are configuring embargo functionality, or if you are
 experiencing mysterious problems with embargoing, please check that your
 reverse proxy is setting any of the well known client IP address headers (ex.,
 HTTP_X_FORWARDED_FOR).
+
+This middleware allows you to:
+
+* Embargoing courses (access restriction by courses)
+* Embargoing site (access restriction of the main site)
+
+Embargo can restrict by states and whitelist/blacklist (IP Addresses
+(ie. 10.0.0.0) or Networks (ie. 10.0.0.0/24)).
+
+Usage:
+
+# Enable the middleware in your settings
+
+# To enable Embargoing by courses, add:
+FEATURES['EMBARGO'] = True # blocked ip will be redirected to /embargo
+
+# To enable Embargoing site:
+FEATURES['EMBARGO_SITE'] = True
+
+# With EMBARGO_SITE, you can define an external to redirect with:
+EMBARGO_SITE_REDIRECT_URL = 'https://www.edx.org/'
+
+# if EMBARGO_SITE_REDIRECT_URL is missing, a HttpResponseForbidden is returned.
+
 """
 import logging
 import pygeoip
@@ -13,6 +36,7 @@ import pygeoip
 from django.core.exceptions import MiddlewareNotUsed
 from django.conf import settings
 from django.shortcuts import redirect
+from django.http import HttpResponseRedirect, HttpResponseForbidden
 from ipware.ip import get_ip
 from util.request import course_id_from_url
 
@@ -23,14 +47,16 @@ log = logging.getLogger(__name__)
 
 class EmbargoMiddleware(object):
     """
-    Middleware for embargoing courses
+    Middleware for embargoing site and courses
 
     This is configured by creating ``EmbargoedCourse``, ``EmbargoedState``, and
     optionally ``IPFilter`` rows in the database, using the django admin site.
     """
     def __init__(self):
+        self.site_enabled = settings.FEATURES.get('EMBARGO_SITE', False)
         # If embargoing is turned off, make this middleware do nothing
-        if not settings.FEATURES.get('EMBARGO', False):
+        if not settings.FEATURES.get('EMBARGO', False) and \
+           not self.site_enabled:
             raise MiddlewareNotUsed()
 
     def process_request(self, request):
@@ -41,21 +67,28 @@ class EmbargoMiddleware(object):
         course_id = course_id_from_url(url)
 
         # If they're trying to access a course that cares about embargoes
-        if EmbargoedCourse.is_embargoed(course_id):
+        if self.site_enabled or EmbargoedCourse.is_embargoed(course_id):
+            response = redirect('embargo')
+            # Set the proper response if site is enabled
+            if self.site_enabled:
+                redirect_url = getattr(settings, 'EMBARGO_SITE_REDIRECT_URL', None)
+                response = HttpResponseRedirect(redirect_url) if redirect_url \
+                           else HttpResponseForbidden('Access Denied')
+
             # If we're having performance issues, add caching here
             ip_addr = get_ip(request)
 
             # if blacklisted, immediately fail
             if ip_addr in IPFilter.current().blacklist_ips:
-                log.info("Embargo: Restricting IP address %s to course %s because IP is blacklisted.", ip_addr, course_id)
-                return redirect('embargo')
+                log.info("Embargo: Restricting IP address %s because IP is blacklisted.", ip_addr)
+                return response
 
             country_code_from_ip = pygeoip.GeoIP(settings.GEOIP_PATH).country_code_by_addr(ip_addr)
             is_embargoed = country_code_from_ip in EmbargoedState.current().embargoed_countries_list
             # Fail if country is embargoed and the ip address isn't explicitly whitelisted
             if is_embargoed and ip_addr not in IPFilter.current().whitelist_ips:
                 log.info(
-                    "Embargo: Restricting IP address %s to course %s because IP is from country %s.",
-                    ip_addr, course_id, country_code_from_ip
+                    "Embargo: Restricting IP address %s because IP is from country %s.",
+                    ip_addr, country_code_from_ip
                 )
-                return redirect('embargo')
+                return response

common/djangoapps/embargo/models.py

@@ -10,6 +10,9 @@ file and check it in at the same time as your model changes. To do that,
 2. ./manage.py lms schemamigration embargo --auto description_of_your_change
 3. Add the migration file created in edx-platform/common/djangoapps/embargo/migrations/
 """
+
+import ipaddr
+
 from django.db import models
 
 from config_models.models import ConfigurationModel
@@ -79,6 +82,30 @@ class IPFilter(ConfigurationModel):
         help_text="A comma-separated list of IP addresses that should fall under embargo restrictions."
     )
 
+    class IPFilterList(object):
+        """
+        Represent a list of IP addresses with support of networks.
+        """
+
+        def __init__(self, ips):
+            self.networks = [ipaddr.IPNetwork(ip) for ip in ips]
+
+        def __iter__(self):
+            for network in self.networks:
+                    yield network
+
+        def __contains__(self, ip):
+            try:
+                ip = ipaddr.IPAddress(ip)
+            except ValueError:
+                return False
+
+            for network in self.networks:
+                if network.Contains(ip):
+                    return True
+
+            return False
+
     @property
     def whitelist_ips(self):
         """
@@ -86,7 +113,7 @@ class IPFilter(ConfigurationModel):
         """
         if self.whitelist == '':
             return []
-        return [addr.strip() for addr in self.whitelist.split(',')]  # pylint: disable=no-member
+        return self.IPFilterList([addr.strip() for addr in self.whitelist.split(',')])  # pylint: disable=no-member
 
     @property
     def blacklist_ips(self):
@@ -95,4 +122,4 @@ class IPFilter(ConfigurationModel):
         """
         if self.blacklist == '':
             return []
-        return [addr.strip() for addr in self.blacklist.split(',')]  # pylint: disable=no-member
+        return self.IPFilterList([addr.strip() for addr in self.blacklist.split(',')])  # pylint: disable=no-member

common/djangoapps/embargo/tests/test_forms.py

@@ -156,8 +156,8 @@ class IPFilterFormTest(TestCase):
         # should be able to do both ipv4 and ipv6
         # spacing should not matter
         form_data = {
-            'whitelist': '127.0.0.1, 2003:dead:beef:4dad:23:46:bb:101',
-            'blacklist': '  18.244.1.5  ,  2002:c0a8:101::42, 18.36.22.1'
+            'whitelist': '127.0.0.1, 2003:dead:beef:4dad:23:46:bb:101, 1.1.0.1/32, 1.0.0.0/24',
+            'blacklist': '  18.244.1.5  ,  2002:c0a8:101::42, 18.36.22.1, 1.0.0.0/16'
         }
         form = IPFilterForm(data=form_data)
         self.assertTrue(form.is_valid())
@@ -169,6 +169,20 @@ class IPFilterFormTest(TestCase):
         for addr in '18.244.1.5, 2002:c0a8:101::42, 18.36.22.1'.split(','):
             self.assertIn(addr.strip(), blacklist)
 
+        # Network tests
+        # ips not in whitelist network
+        for addr in '1.1.0.2, 1.0.1.0'.split(','):
+            self.assertNotIn(addr.strip(), whitelist)
+        # ips in whitelist network
+        for addr in '1.1.0.1, 1.0.0.100'.split(','):
+            self.assertIn(addr.strip(), whitelist)
+        # ips not in blacklist network
+        for addr in '2.0.0.0, 1.1.0.0'.split(','):
+            self.assertNotIn(addr.strip(), blacklist)
+        # ips in blacklist network
+        for addr in '1.0.100.0, 1.0.0.10'.split(','):
+            self.assertIn(addr.strip(), blacklist)
+
         # Test clearing by adding an empty list is OK too
         form_data = {
             'whitelist': '',
@@ -183,15 +197,15 @@ class IPFilterFormTest(TestCase):
     def test_add_invalid_ips(self):
         # test adding invalid ip addresses
         form_data = {
-            'whitelist': '.0.0.1, :dead:beef:::',
-            'blacklist': '  18.244.*  ,  999999:c0a8:101::42'
+            'whitelist': '.0.0.1, :dead:beef:::, 1.0.0.0/55',
+            'blacklist': '  18.244.*  ,  999999:c0a8:101::42, 1.0.0.0/'
         }
         form = IPFilterForm(data=form_data)
         self.assertFalse(form.is_valid())
 
-        wmsg = "Invalid IP Address(es): [u'.0.0.1', u':dead:beef:::'] Please fix the error(s) and try again."
+        wmsg = "Invalid IP Address(es): [u'.0.0.1', u':dead:beef:::', u'1.0.0.0/55'] Please fix the error(s) and try again."
         self.assertEquals(wmsg, form._errors['whitelist'][0])  # pylint: disable=protected-access
-        bmsg = "Invalid IP Address(es): [u'18.244.*', u'999999:c0a8:101::42'] Please fix the error(s) and try again."
+        bmsg = "Invalid IP Address(es): [u'18.244.*', u'999999:c0a8:101::42', u'1.0.0.0/'] Please fix the error(s) and try again."
         self.assertEquals(bmsg, form._errors['blacklist'][0])  # pylint: disable=protected-access
 
         with self.assertRaisesRegexp(ValueError, "The IPFilter could not be created because the data didn't validate."):

common/djangoapps/embargo/tests/test_middleware.py

@@ -130,6 +130,62 @@ class EmbargoMiddlewareTests(TestCase):
         self.assertEqual(response.status_code, 200)
 
     @unittest.skipUnless(settings.ROOT_URLCONF == 'lms.urls', 'Test only valid in lms')
+    def test_ip_network_exceptions(self):
+        # Explicitly whitelist/blacklist some IP networks
+        IPFilter(
+            whitelist='1.0.0.1/24',
+            blacklist='5.0.0.0/16,1.1.0.0/24',
+            changed_by=self.user,
+            enabled=True
+        ).save()
+
+        # Accessing an embargoed page from a blocked IP that's been whitelisted with a network
+        # should succeed
+        response = self.client.get(self.embargoed_page, HTTP_X_FORWARDED_FOR='1.0.0.0', REMOTE_ADDR='1.0.0.0')
+        self.assertEqual(response.status_code, 200)
+
+        # Accessing a regular course from a blocked IP that's been whitelisted with a network
+        # should succeed
+        response = self.client.get(self.regular_page, HTTP_X_FORWARDED_FOR='1.0.0.0', REMOTE_ADDR='1.0.0.0')
+        self.assertEqual(response.status_code, 200)
+
+        # Accessing an embargoed course from non-embargoed IP that's been blacklisted with a network
+        #  should cause a redirect
+        response = self.client.get(self.embargoed_page, HTTP_X_FORWARDED_FOR='5.0.0.100', REMOTE_ADDR='5.0.0.100')
+        self.assertEqual(response.status_code, 302)
+        # Following the redirect should give us the embargo page
+        response = self.client.get(
+            self.embargoed_page,
+            HTTP_X_FORWARDED_FOR='5.0.0.0',
+            REMOTE_ADDR='1.0.0.0',
+            follow=True
+        )
+        self.assertIn(self.embargo_text, response.content)
+
+        # Accessing an embargoed course from non-embargoed IP that's been blaclisted with a network
+        # should cause a redirect
+        response = self.client.get(self.embargoed_page, HTTP_X_FORWARDED_FOR='1.1.0.1', REMOTE_ADDR='1.1.0.1')
+        self.assertEqual(response.status_code, 302)
+        # Following the redirect should give us the embargo page
+        response = self.client.get(
+            self.embargoed_page,
+            HTTP_X_FORWARDED_FOR='1.1.0.0',
+            REMOTE_ADDR='1.1.0.0',
+            follow=True
+        )
+        self.assertIn(self.embargo_text, response.content)
+
+        # Accessing an embargoed from a blocked IP that's not blacklisted by the network rule.
+        # should succeed
+        response = self.client.get(self.embargoed_page, HTTP_X_FORWARDED_FOR='1.1.1.0', REMOTE_ADDR='1.1.1.0')
+        self.assertEqual(response.status_code, 200)
+
+        # Accessing a regular course from a non-embargoed IP that's been blacklisted
+        # should succeed
+        response = self.client.get(self.regular_page, HTTP_X_FORWARDED_FOR='5.0.0.0', REMOTE_ADDR='5.0.0.0')
+        self.assertEqual(response.status_code, 200)
+
+    @unittest.skipUnless(settings.ROOT_URLCONF == 'lms.urls', 'Test only valid in lms')
     @mock.patch.dict(settings.FEATURES, {'EMBARGO': False})
     def test_countries_embargo_off(self):
         # When the middleware is turned off, all requests should go through
@@ -157,3 +213,25 @@ class EmbargoMiddlewareTests(TestCase):
         # Accessing a regular course from a non-embargoed IP that's been blacklisted should succeed
         response = self.client.get(self.regular_page, HTTP_X_FORWARDED_FOR='5.0.0.0', REMOTE_ADDR='5.0.0.0')
         self.assertEqual(response.status_code, 200)
+
+    @unittest.skipUnless(settings.ROOT_URLCONF == 'lms.urls', 'Test only valid in lms')
+    @mock.patch.dict(settings.FEATURES, {'EMBARGO': False, 'EMBARGO_SITE': True})
+    def test_embargo_off_embargo_site_on(self):
+        # When the middleware is turned on with SITE, main site access should be restricted
+        # Accessing a regular page from a blocked IP is denied.
+        response = self.client.get(self.regular_page, HTTP_X_FORWARDED_FOR='1.0.0.0', REMOTE_ADDR='1.0.0.0')
+        self.assertEqual(response.status_code, 403)
+
+        # Accessing a regular page from a non blocked IP should succeed
+        response = self.client.get(self.regular_page, HTTP_X_FORWARDED_FOR='5.0.0.0', REMOTE_ADDR='5.0.0.0')
+        self.assertEqual(response.status_code, 200)
+
+    @unittest.skipUnless(settings.ROOT_URLCONF == 'lms.urls', 'Test only valid in lms')
+    @mock.patch.dict(settings.FEATURES, {'EMBARGO': False, 'EMBARGO_SITE': True})
+    @override_settings(EMBARGO_SITE_REDIRECT_URL='https://www.edx.org/')
+    def test_embargo_off_embargo_site_on_with_redirect_url(self):
+        # When the middleware is turned on with EMBARGO_SITE, main site access
+        # should be restricted. Accessing a regular page from a blocked IP is
+        # denied, and redirected to EMBARGO_SITE_REDIRECT_URL rather than returning a 403.
+        response = self.client.get(self.regular_page, HTTP_X_FORWARDED_FOR='1.0.0.0', REMOTE_ADDR='1.0.0.0')
+        self.assertEqual(response.status_code, 302)

common/djangoapps/embargo/tests/test_models.py

@@ -78,3 +78,19 @@ class EmbargoModelsTest(TestCase):
         self.assertTrue(whitelist in cwhitelist)
         cblacklist = IPFilter.current().blacklist_ips
         self.assertTrue(blacklist in cblacklist)
+
+        # network tests
+        whitelist = '1.0.0.0/24'
+        blacklist = '1.1.0.0/16'
+
+        IPFilter(whitelist=whitelist, blacklist=blacklist).save()
+
+        cwhitelist = IPFilter.current().whitelist_ips
+        self.assertTrue('1.0.0.100' in cwhitelist)
+        self.assertTrue('1.0.0.10' in cwhitelist)
+        self.assertFalse('1.0.1.0' in cwhitelist)
+        cblacklist = IPFilter.current().blacklist_ips
+        self.assertTrue('1.1.0.0' in cblacklist)
+        self.assertTrue('1.1.0.1' in cblacklist)
+        self.assertTrue('1.1.1.0' in cblacklist)
+        self.assertFalse('1.2.0.0' in cblacklist)

lms/envs/common.py

@@ -228,6 +228,9 @@ FEATURES = {
     # Toggle embargo functionality
     'EMBARGO': False,
 
+    # Toggle embargo site functionality
+    'EMBARGO_SITE': False,
+
     # Whether the Wiki subsystem should be accessible via the direct /wiki/ paths. Setting this to True means
     # that people can submit content and modify the Wiki in any arbitrary manner. We're leaving this as True in the
     # defaults, so that we maintain current behavior

requirements/edx/base.txt

@@ -91,6 +91,9 @@ sphinx_rtd_theme==0.1.5
 Babel==1.3
 transifex-client==0.10
 
+# Ip network support for Embargo feature
+ipaddr==2.1.11
+
 # We've tried several times to update the debug toolbar to version 1.0.1,
 # and had problems each time, resulting in us rolling back to 0.9.4. Before
 # submitting another pull request to do this update, check the following: