#!/usr/bin/env python3
#
# Copyright (C) 2021 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/>.

# This is a Python hook script which is invoked whenever a PPPoE session goes
# "ip-up". It will call into our vyos.ifconfig library and will then execute
# common tasks for the PPPoE interface. The reason we have to "hook" this is
# that we can not create a pppoeX interface in advance in linux and then connect
# pppd to this already existing interface.

from sys import argv
from sys import exit

from syslog import syslog
from syslog import openlog
from syslog import LOG_PID
from syslog import LOG_INFO

from vyos.configquery import ConfigTreeQuery
from vyos.ifconfig import PPPoEIf
from vyos.util import read_file

# When the ppp link comes up, this script is called with the following
# parameters
#       $1      the interface name used by pppd (e.g. ppp3)
#       $2      the tty device name
#       $3      the tty device speed
#       $4      the local IP address for the interface
#       $5      the remote IP address
#       $6      the parameter specified by the 'ipparam' option to pppd

if (len(argv) < 7):
    exit(1)

interface = argv[6]
dialer_pid = read_file(f'/var/run/{interface}.pid')

openlog(ident=f'pppd[{dialer_pid}]', facility=LOG_INFO)
syslog('executing ' + argv[0])

conf = ConfigTreeQuery()
pppoe = conf.get_config_dict(['interfaces', 'pppoe', argv[6]],
                             get_first_key=True, key_mangling=('-', '_'))
pppoe['ifname'] = argv[6]

p = PPPoEIf(pppoe['ifname'])
p.update(pppoe)