Implement middleware for admin views

- Add AdminMiddleware to deny non admin users
- Add decorator to mark views as "non admin"

plinth/__main__.py

@@ -234,6 +234,7 @@ def configure_django():
             'django.contrib.auth.middleware.AuthenticationMiddleware',
             'django.contrib.messages.middleware.MessageMiddleware',
             'django.middleware.clickjacking.XFrameOptionsMiddleware',
+            'plinth.middleware.AdminMiddleware',
             'stronghold.middleware.LoginRequiredMiddleware',
             'plinth.modules.first_boot.middleware.FirstBootMiddleware',
             'plinth.middleware.SetupMiddleware',

plinth/middleware.py

@@ -16,16 +16,19 @@
 #
 
 """
-Django middleware to show pre-setup message and setup progress.
+Common Django middleware.
 """
 
 from django import urls
 from django.conf import settings
 from django.contrib import messages
 from django.contrib.auth.decorators import login_required
+from django.core.exceptions import PermissionDenied
 from django.utils.translation import ugettext_lazy as _
 import logging
 
+from stronghold.utils import is_view_func_public
+
 import plinth
 from plinth.package import PackageException
 from . import views
@@ -35,7 +38,9 @@ logger = logging.getLogger(__name__)
 
 
 class SetupMiddleware(object):
-    """Show setup page or progress if setup is neccessary or running."""
+    """
+    Django middleware to show pre-setup message and setup progress.
+    """
 
     @staticmethod
     def process_view(request, view_func, view_args, view_kwargs):
@@ -86,3 +91,17 @@ class SetupMiddleware(object):
         # Only allow logged-in users to access any setup page
         view = login_required(views.SetupView.as_view())
         return view(request, setup_helper=module.setup_helper)
+
+
+class AdminMiddleware(object):
+    """
+    Django middleware for authenticating requests for admin areas
+    """
+
+    @staticmethod
+    def process_view(request, view_func, view_args, view_kwargs):
+        if is_view_func_public(view_func) or hasattr(view_func, 'IS_NON_ADMIN'):
+            return
+
+        if not request.user.groups.filter(name='admin').exists():
+            raise PermissionDenied

plinth/modules/users/urls.py

@@ -37,9 +37,9 @@ urlpatterns = [
     url(r'^sys/users/(?P<slug>[\w.@+-]+)/change_password/$',
         views.UserChangePassword.as_view(), name='change_password'),
     # Add Django's login/logout urls
-    url(r'^accounts/login/$', auth_views.login,
+    url(r'^accounts/login/$', public(auth_views.login),
         {'template_name': 'login.html'}, name='login'),
-    url(r'^accounts/logout/$', auth_views.logout,
+    url(r'^accounts/logout/$', public(auth_views.logout),
         {'next_page': reverse_lazy('index')}, name='logout'),
     url(r'^users/firstboot/$', public(views.FirstBootView.as_view()),
         name='firstboot'),

plinth/tests/test_middleware.py

@@ -22,12 +22,14 @@ Test module for Plinth's custom middleware.
 from unittest.mock import Mock, patch
 
 from django.contrib.auth.models import AnonymousUser, User
+from django.core.exceptions import PermissionDenied
 from django.http import HttpResponse
 from django.test import TestCase
 from django.test.client import RequestFactory
+from stronghold.decorators import public
 
 from plinth import cfg
-from plinth.middleware import SetupMiddleware
+from plinth.middleware import SetupMiddleware, AdminMiddleware
 
 
 class TestSetupMiddleware(TestCase):
@@ -131,3 +133,93 @@ class TestSetupMiddleware(TestCase):
         self.assertIsNone(response)
         assert messages_success.called
         module.setup_helper.collect_result.assert_called_once_with()
+
+
+class TestAdminMiddleware(TestCase):
+    """Test cases for admin middleware."""
+    @classmethod
+    def setUpClass(cls):
+        """Setup all the test cases."""
+        super(TestAdminMiddleware, cls).setUpClass()
+
+        cfg.read()
+
+    def setUp(self):
+        """Setup each test case before execution."""
+        super(TestAdminMiddleware, self).setUp()
+
+        self.middleware = AdminMiddleware()
+
+    @patch('django.contrib.messages.success')
+    @patch('plinth.module_loader.loaded_modules')
+    @patch('django.urls.resolve')
+    @patch('django.urls.reverse', return_value='users:login')
+    def test_that_admin_view_is_denied_for_usual_user(self, reverse, resolve, loaded_modules, messages_success):
+        """Test that normal user is denied for an admin view"""
+
+        self.kwargs = {
+            'view_func': HttpResponse,
+            'view_args': [],
+            'view_kwargs': {},
+        }
+
+        resolve.return_value.namespaces = ['mockapp']
+        loaded_modules.__getitem__.return_value = Mock()
+
+        request = RequestFactory().get('/plinth/mockapp')
+        request.user = Mock()
+        exists_fn = Mock()
+        exists_fn.exists = Mock(return_value=False)
+        request.user.groups.filter.return_value = exists_fn
+
+        self.assertRaises(PermissionDenied, self.middleware.process_view, request, **self.kwargs)
+
+    @patch('django.contrib.messages.success')
+    @patch('plinth.module_loader.loaded_modules')
+    @patch('django.urls.resolve')
+    @patch('django.urls.reverse', return_value='users:login')
+    def test_that_admin_view_is_allowed_for_admin_user(self, reverse, resolve, loaded_modules, messages_success):
+        """Test that admin user is allowed for an admin view"""
+
+        self.kwargs = {
+            'view_func': HttpResponse,
+            'view_args': [],
+            'view_kwargs': {},
+        }
+
+        resolve.return_value.namespaces = ['mockapp']
+        loaded_modules.__getitem__.return_value = Mock()
+
+        request = RequestFactory().get('/plinth/mockapp')
+        request.user = Mock()
+        exists_fn = Mock()
+        exists_fn.exists = Mock(return_value=True)
+        request.user.groups.filter.return_value = exists_fn
+
+        response = self.middleware.process_view(request, **self.kwargs)
+        self.assertIsNone(response)
+
+    @patch('django.contrib.messages.success')
+    @patch('plinth.module_loader.loaded_modules')
+    @patch('django.urls.resolve')
+    @patch('django.urls.reverse', return_value='users:login')
+    def test_that_public_view_is_allowed_for_normal_user(self, reverse, resolve, loaded_modules, messages_success):
+        """Test that normal user is allowed for an public view"""
+
+        self.kwargs = {
+            'view_func': public(HttpResponse),
+            'view_args': [],
+            'view_kwargs': {},
+        }
+
+        resolve.return_value.namespaces = ['mockapp']
+        loaded_modules.__getitem__.return_value = Mock()
+
+        request = RequestFactory().get('/plinth/mockapp')
+        request.user = Mock()
+        exists_fn = Mock()
+        exists_fn.exists = Mock(return_value=False)
+        request.user.groups.filter.return_value = exists_fn
+
+        response = self.middleware.process_view(request, **self.kwargs)
+        self.assertIsNone(response)

plinth/utils.py

@@ -16,7 +16,7 @@
 #
 
 """
-Miscelleneous utility method.
+Miscellaneous utility methods.
 """
 
 import importlib
@@ -44,3 +44,10 @@ def _format_lazy(string, *args, **kwargs):
 
 
 format_lazy = lazy(_format_lazy, str)
+
+
+def non_admin_view(func):
+    """Decorator to mark a view as non admin."""
+
+    setattr(func, "IS_NON_ADMIN", True)
+    return func