text: #!/usr/bin/env python
  
  import socket
  import unittest
  from framework import VppTestCase, VppTestRunner
  from template_bd import BridgeDomain
  
  from scapy.layers.l2 import Ether
  from scapy.layers.inet6 import IPv6, UDP
  from scapy.layers.vxlan import VXLAN
  from scapy.utils import atol
  
  
  class TestVxlan6(BridgeDomain, VppTestCase):
      """ VXLAN over IPv6 Test Case """
  
      def __init__(self, *args):
          BridgeDomain.__init__(self)
          VppTestCase.__init__(self, *args)
  
      def encapsulate(self, pkt, vni):
          """
          Encapsulate the original payload frame by adding VXLAN header with its
          UDP, IP and Ethernet fields
          """
          return (Ether(src=self.pg0.remote_mac, dst=self.pg0.local_mac) /
                  IPv6(src=self.pg0.remote_ip6, dst=self.pg0.local_ip6) /
                  UDP(sport=self.dport, dport=self.dport, chksum=0) /
                  VXLAN(vni=vni, flags=self.flags) /
                  pkt)
  
      @classmethod
      def ip_range(cls, s, e):
          """ range of remote ip's """
          tmp = cls.pg0.remote_ip6.rsplit(':', 1)[0]
          return ("%s:%x" % (tmp, i) for i in range(s, e))
  
      def encap_mcast(self, pkt, src_ip, src_mac, vni):
          """
          Encapsulate the original payload frame by adding VXLAN header with its
          UDP, IP and Ethernet fields
          """
          return (Ether(src=src_mac, dst=self.mcast_mac) /
                  IPv6(src=src_ip, dst=self.mcast_ip6) /
                  UDP(sport=self.dport, dport=self.dport, chksum=0) /
                  VXLAN(vni=vni, flags=self.flags) /
                  pkt)
  
      def decapsulate(self, pkt):
          """
          Decapsulate the original payload frame by removing VXLAN header
          """
          # check if is set I flag
          self.assertEqual(pkt[VXLAN].flags, int('0x8', 16))
          return pkt[VXLAN].payload
  
      # Method for checking VXLAN encapsulation.
      #
      def check_encapsulation(self, pkt, vni, local_only=False, mcast_pkt=False):
          # TODO: add error messages
          # Verify source MAC is VPP_MAC and destination MAC is MY_MAC resolved
          #  by VPP using ARP.
          self.assertEqual(pkt[Ether].src, self.pg0.local_mac)
          if not local_only:
              if not mcast_pkt:
                  self.assertEqual(pkt[Ether].dst, self.pg0.remote_mac)
              else:
                  self.assertEqual(pkt[Ether].dst, type(self).mcast_mac)
          # Verify VXLAN tunnel source IP is VPP_IP and destination IP is MY_IP.
          self.assertEqual(pkt[IPv6].src, self.pg0.local_ip6)
          if not local_only:
              if not mcast_pkt:
                  self.assertEqual(pkt[IPv6].dst, self.pg0.remote_ip6)
              else:
                  self.assertEqual(pkt[IPv6].dst, type(self).mcast_ip6)
          # Verify UDP destination port is VXLAN 4789, source UDP port could be
          #  arbitrary.
          self.assertEqual(pkt[UDP].dport, type(self).dport)
          # TODO: checksum check
          # Verify VNI
          self.assertEqual(pkt[VXLAN].vni, vni)
  
      @classmethod
      def create_vxlan_flood_test_bd(cls, vni, n_ucast_tunnels):
          # Create 10 ucast vxlan tunnels under bd
          start = 10
          end = start + n_ucast_tunnels
          next_hop = cls.pg0.remote_ip6n
          for dest_ip6 in cls.ip_range(start, end):
              dest_ip6n = socket.inet_pton(socket.AF_INET6, dest_ip6)
              # add host route so dest ip will not be resolved
              cls.vapi.ip_add_del_route(dst_address=dest_ip6n,
                                        dst_address_length=128,
                                        next_hop_address=next_hop, is_ipv6=1)
              r = cls.vapi.vxlan_add_del_tunnel(src_address=cls.pg0.local_ip6n,
                                                dst_address=dest_ip6n, is_ipv6=1,
                                                vni=vni)
              cls.vapi.sw_interface_set_l2_bridge(rx_sw_if_index=r.sw_if_index,
                                                  bd_id=vni)
  
      @classmethod
      def add_mcast_tunnels_load(cls):
          cls.add_del_mcast_tunnels_load(is_add=1)
  
      @classmethod
      def del_mcast_tunnels_load(cls):
          cls.add_del_mcast_tunnels_load(is_add=0)
  
      # Class method to start the VXLAN test case.
      #  Overrides setUpClass method in VppTestCase class.
      #  Python try..except statement is used to ensure that the tear down of
      #  the class will be executed even if exception is raised.
      #  @param cls The class pointer.
      @classmethod
      def setUpClass(cls):
          super(TestVxlan6, cls).setUpClass()
  
          try:
              cls.dport = 4789
              cls.flags = 0x8
  
              # Create 2 pg interfaces.
              cls.create_pg_interfaces(range(4))
              for pg in cls.pg_interfaces:
                  pg.admin_up()
  
              # Configure IPv4 addresses on VPP pg0.
              cls.pg0.config_ip6()
  
              # Resolve MAC address for VPP's IP address on pg0.
              cls.pg0.resolve_ndp()
  
              cls.mcast_ip6 = 'ff0e::1'
              cls.mcast_ip6n = socket.inet_pton(socket.AF_INET6, cls.mcast_ip6)
              cls.mcast_mac = "33:33:00:00:00:%02x" % (1)
  
              # Create VXLAN VTEP on VPP pg0, and put vxlan_tunnel0 and pg1
              #  into BD.
              cls.single_tunnel_bd = 1
              r = cls.vapi.vxlan_add_del_tunnel(src_address=cls.pg0.local_ip6n,
                                                dst_address=cls.pg0.remote_ip6n,
                                                is_ipv6=1,
                                                vni=cls.single_tunnel_bd)
              cls.vapi.sw_interface_set_l2_bridge(rx_sw_if_index=r.sw_if_index,
                                                  bd_id=cls.single_tunnel_bd)
              cls.vapi.sw_interface_set_l2_bridge(
                  rx_sw_if_index=cls.pg1.sw_if_index, bd_id=cls.single_tunnel_bd)
  
              # Setup vni 2 to test multicast flooding
              cls.n_ucast_tunnels = 10
              cls.mcast_flood_bd = 2
              cls.create_vxlan_flood_test_bd(cls.mcast_flood_bd,
                                             cls.n_ucast_tunnels)
              r = cls.vapi.vxlan_add_del_tunnel(src_address=cls.pg0.local_ip6n,
                                                dst_address=cls.mcast_ip6n,
                                                mcast_sw_if_index=1, is_ipv6=1,
                                                vni=cls.mcast_flood_bd)
              cls.vapi.sw_interface_set_l2_bridge(rx_sw_if_index=r.sw_if_index,
                                                  bd_id=cls.mcast_flood_bd)
              cls.vapi.sw_interface_set_l2_bridge(
                  rx_sw_if_index=cls.pg2.sw_if_index, bd_id=cls.mcast_flood_bd)
  
              # Setup vni 3 to test unicast flooding
              cls.ucast_flood_bd = 3
              cls.create_vxlan_flood_test_bd(cls.ucast_flood_bd,
                                             cls.n_ucast_tunnels)
              cls.vapi.sw_interface_set_l2_bridge(
                  rx_sw_if_index=cls.pg3.sw_if_index, bd_id=cls.ucast_flood_bd)
          except Exception:
              super(TestVxlan6, cls).tearDownClass()
              raise
  
      @classmethod
      def tearDownClass(cls):
          super(TestVxlan6, cls).tearDownClass()
  
      # Method to define VPP actions before tear down of the test case.
      #  Overrides tearDown method in VppTestCase class.
      #  @param self The object pointer.
      def tearDown(self):
          super(TestVxlan6, self).tearDown()
  
      def show_commands_at_teardown(self):
          self.logger.info(self.vapi.cli("show bridge-domain 1 detail"))
          self.logger.info(self.vapi.cli("show bridge-domain 2 detail"))
          self.logger.info(self.vapi.cli("show bridge-domain 3 detail"))
          self.logger.info(self.vapi.cli("show vxlan tunnel"))
  
  
  if __name__ == '__main__':
      unittest.main(testRunner=VppTestRunner)
  