tor: Add option to use upstream bridges

actions/tor

@@ -63,6 +63,16 @@ def parse_arguments():
     configure.add_argument('--apt-transport-tor',
                            choices=['enable', 'disable'],
                            help='Configure package download over Tor')
+    configure.add_argument('--use-upstream-bridges',
+                           choices=['enable', 'disable'],
+                           help='Configure use of upstream bridges')
+
+    upstream = subparsers.add_parser(
+        'set-upstream-bridges', help='Set list of upstream bridges')
+    upstream.add_argument('--bridges',
+                          help='List of upstream bridges to use')
+
+    subparsers.add_parser('restart', help='Restart Tor')
 
     return parser.parse_args()
 
@@ -137,6 +147,11 @@ def subcommand_configure(arguments):
     if arguments.service == 'disable':
         _disable()
 
+    restart = arguments.service is None and \
+              arguments.hidden_service is None and \
+              arguments.relay is None and arguments.bridge_relay is None
+    _use_upstream_bridges(arguments.use_upstream_bridges, restart=restart)
+
     restart = arguments.service is None and arguments.hidden_service is None
     _enable_relay(arguments.relay, arguments.bridge_relay, restart=restart)
 
@@ -155,15 +170,50 @@ def subcommand_configure(arguments):
         _disable_apt_transport_tor()
 
 
+def subcommand_set_upstream_bridges(arguments):
+    """Set list of upstream bridges."""
+    aug = augeas_load()
+
+    aug.remove(TOR_CONFIG + '/Bridge')
+    if arguments.bridges:
+        bridges = arguments.bridges.split('\n')
+        for bridge in bridges:
+            if bridge.strip():
+                aug.set(TOR_CONFIG + '/Bridge[last() + 1]', bridge.strip())
+
+    aug.save()
+
+
+def subcommand_restart(_):
+    """Restart Tor."""
+    if is_enabled() and is_running():
+        action_utils.service_restart('tor')
+
+
 def get_status():
     """Return dict with Tor status."""
     aug = augeas_load()
-    return {'relay_enabled': _is_relay_enabled(aug),
+    return {'use_upstream_bridges': _are_upstream_bridges_enabled(aug),
+            'upstream_bridges': _get_upstream_bridges(aug),
+            'relay_enabled': _is_relay_enabled(aug),
             'bridge_relay_enabled': _is_bridge_relay_enabled(aug),
             'ports': _get_ports(),
             'hidden_service': _get_hidden_service(aug)}
 
 
+def _are_upstream_bridges_enabled(aug):
+    """Return whether upstream bridges are being used."""
+    use_bridges = aug.get(TOR_CONFIG + '/UseBridges')
+    return use_bridges == '1'
+
+
+def _get_upstream_bridges(aug):
+    """Return upstream bridges separated by newlines."""
+    matches = aug.match(TOR_CONFIG + '/Bridge')
+    bridges = [aug.get(match) for match in matches]
+    return '\n'.join(bridges)
+
+
 def _is_relay_enabled(aug):
     """Return whether a relay is enabled."""
     orport = aug.get(TOR_CONFIG + '/ORPort')
@@ -262,6 +312,26 @@ def _disable():
     action_utils.service_disable('tor@plinth')
 
 
+def _use_upstream_bridges(use_upstream_bridges=None, restart=True, aug=None):
+    """Enable use of upstream bridges."""
+    if use_upstream_bridges is None:
+        return
+
+    if not aug:
+        aug = augeas_load()
+
+    if use_upstream_bridges == 'enable':
+        aug.set(TOR_CONFIG + '/UseBridges', '1')
+    elif use_upstream_bridges == 'disable':
+        aug.set(TOR_CONFIG + '/UseBridges', '0')
+
+    aug.save()
+
+    if restart:
+        if is_enabled() and is_running():
+            action_utils.service_restart('tor')
+
+
 def _enable_relay(relay=None, bridge=None, restart=True, aug=None):
     """Enable Tor bridge relay."""
     if relay is None and bridge is None:

plinth/modules/tor/forms.py

@@ -20,6 +20,7 @@ Forms for configuring Tor.
 """
 
 from django import forms
+from django.forms import widgets
 from django.utils.translation import ugettext_lazy as _
 
 from plinth import cfg
@@ -62,3 +63,18 @@ class TorForm(forms.Form):  # pylint: disable=W0232
                     'network for installations and upgrades. This adds a '
                     'degree of privacy and security during software '
                     'downloads.'))
+    use_upstream_bridges = forms.BooleanField(
+        label=_('Use upstream bridges to connect to Tor network'),
+        required=False,
+        help_text=_('When enabled, the bridges configured below will be used '
+                    'to connect to the Tor network. This will disable relay '
+                    'modes. Use this option only if you cannot connect to '
+                    'the Tor network directly.'))
+    upstream_bridges = forms.CharField(
+        widget=widgets.Textarea,
+        label=_('Upstream bridges'),
+        required=False,
+        help_text=_('If you need to use a bridge to connect to Tor network, '
+                    'you can get some bridges from '
+                    'https://bridges.torproject.org/ and paste the bridge '
+                    'information here.'))

plinth/modules/tor/templates/tor.html

@@ -151,6 +151,20 @@
                 $('#id_tor-bridge_relay_enabled').prop('checked', false);
             }
         }).change();
+
+        $('#id_tor-use_upstream_bridges').change(function() {
+            if ($('#id_tor-use_upstream_bridges').prop('checked')) {
+                $('#id_tor-upstream_bridges').show('slow');
+                $('label[for="id_tor-upstream_bridges"]').show('slow');
+                $('label[for="id_tor-upstream_bridges"]').parent().show('slow');
+                $('#id_tor-relay_enabled').prop('checked', false);
+                $('#id_tor-bridge_relay_enabled').prop('checked', false);
+            } else {
+                $('#id_tor-upstream_bridges').hide('slow');
+                $('label[for="id_tor-upstream_bridges"]').hide('slow');
+                $('label[for="id_tor-upstream_bridges"]').parent().hide('slow');
+            }
+        }).change();
     })(jQuery);
   // @license-end
   </script>

plinth/modules/tor/utils.py

@@ -64,6 +64,8 @@ def get_status():
 
     return {'enabled': is_enabled(),
             'is_running': is_running(),
+            'use_upstream_bridges': status['use_upstream_bridges'],
+            'upstream_bridges': status['upstream_bridges'],
             'relay_enabled': status['relay_enabled'],
             'bridge_relay_enabled': status['bridge_relay_enabled'],
             'ports': ports,

plinth/modules/tor/views.py

@@ -74,6 +74,15 @@ def __apply_changes(request, old_status, new_status):
         # Already running a configuration task
         return
 
+    needs_restart = False
+
+    if old_status['upstream_bridges'] != new_status['upstream_bridges']:
+        if new_status['enabled'] and new_status['use_upstream_bridges']:
+            actions.superuser_run(
+                'tor', ['set-upstream-bridges', '--bridges',
+                        new_status['upstream_bridges']])
+            needs_restart = True
+
     arguments = []
 
     if old_status['enabled'] != new_status['enabled']:
@@ -102,11 +111,22 @@ def __apply_changes(request, old_status, new_status):
             arg_value = 'enable'
         arguments.extend(['--apt-transport-tor', arg_value])
 
+    if old_status['use_upstream_bridges'] != \
+       new_status['use_upstream_bridges']:
+        arg_value = 'disable'
+        if new_status['enabled'] and new_status['use_upstream_bridges']:
+            arg_value = 'enable'
+        arguments.extend(['--use-upstream-bridges', arg_value])
+
     if arguments:
         config_process = actions.superuser_run(
             'tor', ['configure'] + arguments, async=True)
     else:
-        messages.info(request, _('Setting unchanged'))
+        if needs_restart:
+            config_process = actions.superuser_run(
+                'tor', ['restart'], async=True)
+        else:
+            messages.info(request, _('Setting unchanged'))
 
 
 def _collect_config_result(request):