core-agent-linux/misc/qvm-features-request

#!/usr/bin/python3
# vim: fileencoding=utf-8

#
# The Qubes OS Project, https://www.qubes-os.org/
#
# Copyright (C) 2010-2016  Joanna Rutkowska <joanna@invisiblethingslab.com>
# Copyright (C)      2016  Wojtek Porczyk <woju@invisiblethingslab.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#

import argparse
import os
import subprocess
import sys

import qubesdb


def is_active(service):
    status = subprocess.call(["systemctl", "is-active", "--quiet", service])
    return status == 0


class FeatureRequestAction(argparse.Action):
    '''Action for argument parser that stores a property.'''
    # pylint: disable=redefined-builtin,too-few-public-methods
    def __init__(self,
            option_strings,
            dest='features',
            metavar='NAME=VALUE',
            required=False,
            help='request a feature with the value'):
        super(FeatureRequestAction, self).__init__(option_strings, dest=dest,
            metavar=metavar, nargs='*', required=required, default={},
            help=help)

    def __call__(self, parser, namespace, values, option_string=None):
        for request in values:
            try:
                feature, value = request.split('=', 1)
            except ValueError:
                parser.error(
                    'invalid feature request token: {!r}'.format(request))

            getattr(namespace, self.dest)[feature] = value


parser = argparse.ArgumentParser(
    description='submit a feature request to the dom0')

parser.add_argument('--commit',
    action='store_true', default=False,
    help='actually send the request (without it, only make entries in qubesdb)')

parser.add_argument('features',
    action=FeatureRequestAction)


def main(args=None):
    args = parser.parse_args(args)
    if not is_active("qubes-qrexec-agent"):
        return
    qdb = qubesdb.QubesDB()
    for feature, value in args.features.items():
        qdb.write('/features-request/' + feature, value)

    if args.commit:
        devnull = os.open(os.devnull, os.O_RDWR)
        subprocess.check_call(
            ['qrexec-client-vm', 'dom0', 'qubes.FeaturesRequest'],
            stdin=devnull, stdout=devnull)

if __name__ == '__main__':
    sys.exit(main())