#!/usr/bin/env python3
#
# Copyright (C) 2024 VyOS maintainers and contributors
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 or later as
# published by the Free Software Foundation.
#
# 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, see <http://www.gnu.org/licenses/>.

# T4982: Retain prior default TLS version (v1.0) when upgrading installations with existing openconnect configurations

import sys

from vyos.configtree import ConfigTree

if len(sys.argv) < 2:
    print("Must specify file name!")
    sys.exit(1)

file_name = sys.argv[1]

with open(file_name, 'r') as f:
    config_file = f.read()


config = ConfigTree(config_file)
cfg_base = ['vpn', 'openconnect']

# bail out early if service is unconfigured
if not config.exists(cfg_base):
    sys.exit(0)

# new default is TLS 1.2 - set explicit old default value of TLS 1.0 for upgraded configurations to keep compatibility
tls_min_path = cfg_base + ['tls-version-min']
if not config.exists(tls_min_path):
    config.set(tls_min_path, value='1.0')

try:
    with open(file_name, 'w') as f:
        f.write(config.to_string())
except OSError as e:
    print("Failed to save the modified config: {}".format(e))
    sys.exit(1)