Don't use actions to check if service is running

- To check whether a service is running does not require root
  privileges.  This can directly be done from a module without any
  action.

- Since actions are allowed to be run using sudo, introducing
  unnecessary sub-commands increases attack surface.

- Simple functions calls are unnecessarily being converted to command
  line invocations and involve parsing response.

- There is a lot of repeated code because of this that can be
  eliminated.

- To generalize this, we need to make all non-root system operations
  directly from module instead of delegating to action commands.

actions/deluge

@@ -65,10 +65,6 @@ def parse_arguments():
     # Disable deluge-web site and stop deluge-web
     subparsers.add_parser('disable', help='Disable deluge-web site')
 
-    # Get whether deluge-web is running
-    subparsers.add_parser('is-running',
-                          help='Get whether deluge-web is running')
-
     return parser.parse_args()
 
 
@@ -94,11 +90,6 @@ def subcommand_disable(_):
     disable()
 
 
-def subcommand_is_running(_):
-    """Get whether deluge-web is running."""
-    print('yes' if action_utils.service_is_running('deluge-web') else 'no')
-
-
 def enable():
     """Start and enable deluge-web service."""
     action_utils.service_enable('deluge-web')

actions/mumble

@@ -45,10 +45,6 @@ def parse_arguments():
     # Disable service
     subparsers.add_parser('disable', help='Disable Mumble service')
 
-    # Get whether daemon is running
-    subparsers.add_parser('is-running',
-                          help='Get whether Mumble daemon is running')
-
     return parser.parse_args()
 
 
@@ -95,11 +91,6 @@ def set_service_enable(enable):
         file.writelines(lines)
 
 
-def subcommand_is_running(_):
-    """Get whether server is running."""
-    print('yes' if action_utils.service_is_running('mumble-server') else 'no')
-
-
 def main():
     """Parse arguments and perform all duties."""
     arguments = parse_arguments()

actions/pagekite

@@ -49,7 +49,6 @@ def parse_arguments():
     subparsers = parser.add_subparsers(dest='subcommand', help='Sub command')
 
     # Enable/disable the pagekite service
-    subparsers.add_parser('is-running', help='Get whether PakeKite is running')
     subparsers.add_parser('start-and-enable', help='Enable PageKite service')
     subparsers.add_parser('stop-and-disable', help='Disable PageKite service')
     subparsers.add_parser('restart', help='Restart PageKite service')
@@ -81,11 +80,6 @@ def parse_arguments():
     return parser.parse_args()
 
 
-def subcommand_is_running(_):
-    """Print whether pagekite is enabled (yes or no)"""
-    print('yes' if action_utils.service_is_running('pagekite') else 'no')
-
-
 def subcommand_restart(_):
     """Restart the pagekite service"""
     action_utils.service_restart('pagekite')

actions/privoxy

@@ -41,8 +41,6 @@ def parse_arguments():
                           help='Get whether Privoxy service is enabled')
     subparsers.add_parser('enable', help='Enable Privoxy service')
     subparsers.add_parser('disable', help='Disable Privoxy service')
-    subparsers.add_parser('is-running',
-                          help='Get whether Privoxy daemon is running')
 
     return parser.parse_args()
 
@@ -83,12 +81,6 @@ def subcommand_disable(_):
     action_utils.service_disable('privoxy')
 
 
-def subcommand_is_running(_):
-    """Get whether server is running."""
-    running = action_utils.service_is_running('privoxy')
-    print('yes' if running else 'no')
-
-
 def main():
     """Parse arguments and perform all duties."""
     arguments = parse_arguments()

actions/tor

@@ -34,9 +34,6 @@ def parse_arguments():
     parser = argparse.ArgumentParser()
     subparsers = parser.add_subparsers(dest='subcommand', help='Sub command')
 
-    # Get whether Tor is running
-    subparsers.add_parser('is-running', help='Get whether Tor is running')
-
     # Enable and start the service
     subparsers.add_parser('enable', help='Enable and start Tor service')
 
@@ -55,11 +52,6 @@ def parse_arguments():
     return parser.parse_args()
 
 
-def subcommand_is_running(_):
-    """Get whether Tor is running"""
-    print('yes' if action_utils.service_is_running('tor') else 'no')
-
-
 def subcommand_enable(_):
     """Enable and start the service."""
     action_utils.service_enable('tor')

actions/transmission

@@ -47,10 +47,6 @@ def parse_arguments():
     # Disable service
     subparsers.add_parser('disable', help='Disable Transmission service')
 
-    # Get whether daemon is running
-    subparsers.add_parser('is-running',
-                          help='Get whether Transmission daemon is running')
-
     # Merge given JSON configration with existing
     merge_configuration = subparsers.add_parser(
         'merge-configuration',
@@ -108,11 +104,6 @@ def set_service_enable(enable):
         file_handle.writelines(lines)
 
 
-def subcommand_is_running(_):
-    """Get whether Transmission is running."""
-    print('yes' if action_utils.service_is_running('transmission-daemon') else 'no')
-
-
 def subcommand_merge_configuration(arguments):
     """Merge given JSON configuration with existing configuration."""
     configuration = arguments.configuration

plinth/action_utils.py

@@ -23,7 +23,10 @@ import subprocess
 
 
 def service_is_running(servicename):
-    """Evaluates whether a service is currently running. Returns boolean"""
+    """Return whether a service is currently running.
+
+    Does not need to run as root.
+    """
     try:
         subprocess.check_output(['systemctl', 'status', servicename])
         return True

plinth/modules/deluge/views.py

@@ -25,6 +25,7 @@ from gettext import gettext as _
 
 from .forms import DelugeForm
 from plinth import actions
+from plinth import action_utils
 from plinth import package
 from plinth.modules import deluge
 
@@ -57,11 +58,8 @@ def get_status():
     output = actions.run('deluge', ['get-enabled'])
     enabled = (output.strip() == 'yes')
 
-    output = actions.run('deluge', ['is-running'])
-    is_running = (output.strip() == 'yes')
-
     status = {'enabled': enabled,
-              'is_running': is_running}
+              'is_running': action_utils.service_is_running('deluge-web')}
 
     return status
 

plinth/modules/mumble/views.py

@@ -26,6 +26,7 @@ import logging
 
 from .forms import MumbleForm
 from plinth import actions
+from plinth import action_utils
 from plinth import package
 from plinth.modules import mumble
 
@@ -65,11 +66,8 @@ def get_status():
     output = actions.run('mumble', ['get-enabled'])
     enabled = (output.strip() == 'yes')
 
-    output = actions.superuser_run('mumble', ['is-running'])
-    is_running = (output.strip() == 'yes')
-
     status = {'enabled': enabled,
-              'is_running': is_running}
+              'is_running': action_utils.service_is_running('mumble')}
 
     return status
 

plinth/modules/pagekite/utils.py

@@ -21,6 +21,7 @@ import logging
 import os
 
 from plinth import actions
+from plinth import action_utils
 
 LOGGER = logging.getLogger(__name__)
 
@@ -91,8 +92,7 @@ def get_pagekite_config():
 
     # PageKite service enabled/disabled
     # This assumes that if pagekite is running it's also enabled as a service
-    output = run(['is-running'])
+    status['enabled'] = action_utils.service_is_running('pagekite')
-    status['enabled'] = (output.split()[0] == 'yes')
 
     # PageKite kite details
     status.update(get_kite_details())

plinth/modules/privoxy/views.py

@@ -26,6 +26,7 @@ import logging
 
 from .forms import PrivoxyForm
 from plinth import actions
+from plinth import action_utils
 from plinth import package
 from plinth.modules import privoxy
 
@@ -65,11 +66,8 @@ def get_status():
     output = actions.run('privoxy', ['get-enabled'])
     enabled = (output.strip() == 'yes')
 
-    output = actions.superuser_run('privoxy', ['is-running'])
-    is_running = (output.strip() == 'yes')
-
     status = {'enabled': enabled,
-              'is_running': is_running}
+              'is_running': action_utils.service_is_running('privoxy')}
 
     return status
 

plinth/modules/tor/tor.py

@@ -25,6 +25,7 @@ from django.template.response import TemplateResponse
 from gettext import gettext as _
 
 from plinth import actions
+from plinth import action_utils
 from plinth import cfg
 from plinth import package
 
@@ -71,8 +72,6 @@ def index(request):
 
 def get_status():
     """Return the current status"""
-    is_running = actions.superuser_run('tor', ['is-running']).strip() == 'yes'
-
     output = actions.superuser_run('tor-get-ports')
     port_info = output.split('\n')
     ports = {}
@@ -99,7 +98,7 @@ def get_status():
         hs_hostname = hs_info[0]
         hs_ports = hs_info[1]
 
-    return {'is_running': is_running,
+    return {'is_running': action_utils.service_is_running('tor'),
             'ports': ports,
             'hs_enabled': hs_enabled,
             'hs_hostname': hs_hostname,

plinth/modules/transmission/views.py

@@ -28,6 +28,7 @@ import socket
 
 from .forms import TransmissionForm
 from plinth import actions
+from plinth import action_utils
 from plinth import package
 from plinth.modules import transmission
 
@@ -69,15 +70,12 @@ def get_status():
     output = actions.run('transmission', ['get-enabled'])
     enabled = (output.strip() == 'yes')
 
-    output = actions.superuser_run('transmission', ['is-running'])
-    is_running = (output.strip() == 'yes')
-
     configuration = open(TRANSMISSION_CONFIG, 'r').read()
     status = json.loads(configuration)
     status = {key.translate(str.maketrans({'-': '_'})): value
               for key, value in status.items()}
     status['enabled'] = enabled
-    status['is_running'] = is_running
+    status['is_running'] = action_utils.service_is_running('transmission-daemon')
     status['hostname'] = socket.gethostname()
 
     return status