#!/usr/bin/env python3

import unittest

from scapy.layers.l2 import Ether
from scapy.layers.inet6 import IPv6

from framework import VppTestCase


class TestL2tp(VppTestCase):
    """ L2TP Test Case """

    @classmethod
    def setUpClass(cls):
        super(TestL2tp, cls).setUpClass()

        cls.create_pg_interfaces(range(1))
        cls.pg0.admin_up()
        cls.pg0.config_ip6()

    def test_l2tp_decap_local(self):
        """ L2TP don't accept packets unless configured """

        pkt = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
               IPv6(src=self.pg0.remote_ip6, dst=self.pg0.local_ip6, nh=115))

        self.pg0.add_stream(pkt)
        self.pg_start()

        # l2tp should not accept packets
        err = self.statistics.get_counter(
            '/err/l2tp-decap-local/l2tpv3 session not found')[0]
        self.assertEqual(err, 0)
        err_count = err

        self.vapi.l2tpv3_create_tunnel(client_address=self.pg0.local_ip6,
                                       our_address=self.pg0.remote_ip6)

        self.pg0.add_stream(pkt)
        self.pg_start()

        # l2tp accepts packets
        err = self.statistics.get_counter(
            '/err/l2tp-decap-local/l2tpv3 session not found')[0]
        self.assertEqual(err, 1)
        err_count = err