# Copyright 2023-2024 VyOS maintainers and contributors <maintainers@vyos.io>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this library.  If not, see <http://www.gnu.org/licenses/>.

# Removes outdated ciphers (DES and Blowfish) from OpenVPN configs

from vyos.configtree import ConfigTree

def migrate(config: ConfigTree) -> None:
    if not config.exists(['interfaces', 'openvpn']):
        # Nothing to do
        return

    ovpn_intfs = config.list_nodes(['interfaces', 'openvpn'])
    for	i in ovpn_intfs:
        # Remove DES and Blowfish from 'encryption cipher'
        cipher_path = ['interfaces', 'openvpn', i, 'encryption', 'cipher']
        if config.exists(cipher_path):
            cipher = config.return_value(cipher_path)
            if cipher in ['des', 'bf128', 'bf256']:
                config.delete(cipher_path)

        ncp_cipher_path = ['interfaces', 'openvpn', i, 'encryption', 'ncp-ciphers']
        if config.exists(ncp_cipher_path):
            ncp_ciphers = config.return_values(['interfaces', 'openvpn', i, 'encryption', 'ncp-ciphers'])
            if 'des' in ncp_ciphers:
                config.delete_value(['interfaces', 'openvpn', i, 'encryption', 'ncp-ciphers'], 'des')

        # Clean up the encryption subtree if the migration procedure left it empty
        if config.exists(['interfaces', 'openvpn', i, 'encryption']) and \
           (config.list_nodes(['interfaces', 'openvpn', i, 'encryption']) == []):
            config.delete(['interfaces', 'openvpn', i, 'encryption'])