test/test_mpls.py

#!/usr/bin/env python

import unittest
import socket

from framework import VppTestCase, VppTestRunner
from vpp_sub_interface import VppSubInterface, VppDot1QSubint, VppDot1ADSubint
from vpp_ip_route import IpRoute, RoutePath, MplsRoute, MplsIpBind

from scapy.packet import Raw
from scapy.layers.l2 import Ether
from scapy.layers.inet import IP, UDP
from scapy.layers.inet6 import IPv6
from scapy.contrib.mpls import MPLS
from util import ppp



class TestMPLS(VppTestCase):
    """ MPLS Test Case """

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

    def setUp(self):
        super(TestMPLS, self).setUp()

        # create 2 pg interfaces
        self.create_pg_interfaces(range(2))

        # setup both interfaces
        # assign them different tables.
        table_id = 0

        for i in self.pg_interfaces:
            i.admin_up()
            i.set_table_ip4(table_id)
            i.set_table_ip6(table_id)
            i.config_ip4()
            i.resolve_arp()
            i.config_ip6()
            i.resolve_ndp()
            i.enable_mpls()
            table_id += 1

    def tearDown(self):
        super(TestMPLS, self).tearDown()

    # the default of 64 matches the IP packet TTL default
    def create_stream_labelled_ip4(self, src_if, mpls_labels, mpls_ttl=255):
        pkts = []
        for i in range(0, 257):
            info = self.create_packet_info(src_if.sw_if_index,
                                           src_if.sw_if_index)
            payload = self.info_to_payload(info)
            p = Ether(dst=src_if.local_mac, src=src_if.remote_mac)

            for ii in range(len(mpls_labels)):
                if ii == len(mpls_labels) - 1:
                    p = p / MPLS(label=mpls_labels[ii], ttl=mpls_ttl, s=1)
                else:
                    p = p / MPLS(label=mpls_labels[ii], ttl=mpls_ttl, s=0)
            p = (p / IP(src=src_if.remote_ip4, dst=src_if.remote_ip4) /
                 UDP(sport=1234, dport=1234) /
                 Raw(payload))
            info.data = p.copy()
            pkts.append(p)
        return pkts

    def create_stream_ip4(self, src_if, dst_ip):
        pkts = []
        for i in range(0, 257):
            info = self.create_packet_info(src_if.sw_if_index,
                                           src_if.sw_if_index)
            payload = self.info_to_payload(info)
            p = (Ether(dst=src_if.local_mac, src=src_if.remote_mac) /
                 IP(src=src_if.remote_ip4, dst=dst_ip) /
                 UDP(sport=1234, dport=1234) /
                 Raw(payload))
            info.data = p.copy()
            pkts.append(p)
        return pkts

    def create_stream_labelled_ip6(self, src_if, mpls_label, mpls_ttl):
        pkts = []
        for i in range(0, 257):
            info = self.create_packet_info(src_if.sw_if_index,
                                           src_if.sw_if_index)
            payload = self.info_to_payload(info)
            p = (Ether(dst=src_if.local_mac, src=src_if.remote_mac) /
                 MPLS(label=mpls_label, ttl=mpls_ttl) /
                 IPv6(src=src_if.remote_ip6, dst=src_if.remote_ip6) /
                 UDP(sport=1234, dport=1234) /
                 Raw(payload))
            info.data = p.copy()
            pkts.append(p)
        return pkts

    def verify_filter(self, capture, sent):
        if not len(capture) == len(sent):
            # filter out any IPv6 RAs from the captur
            for p in capture:
                if (p.haslayer(IPv6)):
                    capture.remove(p)
        return capture

    def verify_capture_ip4(self, src_if, capture, sent):
        try:
            capture = self.verify_filter(capture, sent)

            self.assertEqual(len(capture), len(sent))

            for i in range(len(capture)):
                tx = sent[i]
                rx = capture[i]

                # the rx'd packet has the MPLS label popped
                eth = rx[Ether]
                self.assertEqual(eth.type, 0x800)

                tx_ip = tx[IP]
                rx_ip = rx[IP]

                self.assertEqual(rx_ip.src, tx_ip.src)
                self.assertEqual(rx_ip.dst, tx_ip.dst)
                # IP processing post pop has decremented the TTL
                self.assertEqual(rx_ip.ttl + 1, tx_ip.ttl)

        except:
            raise

    def verify_mpls_stack(self, rx, mpls_labels, ttl=255, num=0):
        # the rx'd packet has the MPLS label popped
        eth = rx[Ether]
        self.assertEqual(eth.type, 0x8847)

        rx_mpls = rx[MPLS]

        for ii in range(len(mpls_labels)):
            self.assertEqual(rx_mpls.label, mpls_labels[ii])
            self.assertEqual(rx_mpls.cos, 0)
            if ii == num:
                self.assertEqual(rx_mpls.ttl, ttl)
            else:
                self.assertEqual(rx_mpls.ttl, 255)

            if ii == len(mpls_labels) - 1:
                self.assertEqual(rx_mpls.s, 1)
            else:
                # not end of stack
                self.assertEqual(rx_mpls.s, 0)
                # pop the label to expose the next
                rx_mpls = rx_mpls[MPLS].payload

    def verify_capture_labelled_ip4(self, src_if, capture, sent,
                                    mpls_labels):
        try:
            capture = self.verify_filter(capture, sent)

            self.assertEqual(len(capture), len(sent))

            for i in range(len(capture)):
                tx = sent[i]
                rx = capture[i]
                tx_ip = tx[IP]
                rx_ip = rx[IP]

                # the MPLS TTL is copied from the IP
                self.verify_mpls_stack(
                    rx, mpls_labels, rx_ip.ttl, len(mpls_labels) - 1)

                self.assertEqual(rx_ip.src, tx_ip.src)
                self.assertEqual(rx_ip.dst, tx_ip.dst)
                # IP processing post pop has decremented the TTL
                self.assertEqual(rx_ip.ttl + 1, tx_ip.ttl)

        except:
            raise

    def verify_capture_tunneled_ip4(self, src_if, capture, sent, mpls_labels):
        try:
            capture = self.verify_filter(capture, sent)

            self.assertEqual(len(capture), len(sent))

            for i in range(len(capture)):
                tx = sent[i]
                rx = capture[i]
                tx_ip = tx[IP]
                rx_ip = rx[IP]

                # the MPLS TTL is 255 since it enters a new tunnel
                self.verify_mpls_stack(
                    rx, mpls_labels, 255, len(mpls_labels) - 1)

                self.assertEqual(rx_ip.src, tx_ip.src)
                self.assertEqual(rx_ip.dst, tx_ip.dst)
                # IP processing post pop has decremented the TTL
                self.assertEqual(rx_ip.ttl + 1, tx_ip.ttl)

        except:
            raise

    def verify_capture_labelled(self, src_if, capture, sent,
                                mpls_labels, ttl=254, num=0):
        try:
            capture = self.verify_filter(capture, sent)

            self.assertEqual(len(capture), len(sent))

            for i in range(len(capture)):
                rx = capture[i]
                self.verify_mpls_stack(rx, mpls_labels, ttl, num)
        except:
            raise

    def verify_capture_ip6(self, src_if, capture, sent):
        try:
            self.assertEqual(len(capture), len(sent))

            for i in range(len(capture)):
                tx = sent[i]
                rx = capture[i]

                # the rx'd packet has the MPLS label popped
                eth = rx[Ether]
                self.assertEqual(eth.type, 0x86DD)

                tx_ip = tx[IPv6]
                rx_ip = rx[IPv6]

                self.assertEqual(rx_ip.src, tx_ip.src)
                self.assertEqual(rx_ip.dst, tx_ip.dst)
                # IP processing post pop has decremented the TTL
                self.assertEqual(rx_ip.hlim + 1, tx_ip.hlim)

        except:
            raise

    def test_swap(self):
        """ MPLS label swap tests """

        #
        # A simple MPLS xconnect - eos label in label out
        #
        route_32_eos = MplsRoute(self, 32, 1,
                                 [RoutePath(self.pg0.remote_ip4,
                                            self.pg0.sw_if_index,
                                            labels=[33])])
        route_32_eos.add_vpp_config()

        #
        # a stream that matches the route for 10.0.0.1
        # PG0 is in the default table
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [32])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled_ip4(self.pg0, rx, tx, [33])

        #
        # A simple MPLS xconnect - non-eos label in label out
        #
        route_32_neos = MplsRoute(self, 32, 0,
                                  [RoutePath(self.pg0.remote_ip4,
                                             self.pg0.sw_if_index,
                                             labels=[33])])
        route_32_neos.add_vpp_config()

        #
        # a stream that matches the route for 10.0.0.1
        # PG0 is in the default table
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [32, 99])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled(self.pg0, rx, tx, [33, 99])

        #
        # An MPLS xconnect - EOS label in IP out
        #
        route_33_eos = MplsRoute(self, 33, 1,
                                 [RoutePath(self.pg0.remote_ip4,
                                            self.pg0.sw_if_index,
                                            labels=[])])
        route_33_eos.add_vpp_config()

        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [33])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_ip4(self.pg0, rx, tx)

        #
        # An MPLS xconnect - non-EOS label in IP out - an invalid configuration
        # so this traffic should be dropped.
        #
        route_33_neos = MplsRoute(self, 33, 0,
                                  [RoutePath(self.pg0.remote_ip4,
                                             self.pg0.sw_if_index,
                                             labels=[])])
        route_33_neos.add_vpp_config()

        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [33, 99])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        try:
            self.assertEqual(0, len(rx))
        except:
            error("MPLS non-EOS packets popped and forwarded")
            error(packet.show())
            raise

        #
        # A recursive EOS x-connect, which resolves through another x-connect
        #
        route_34_eos = MplsRoute(self, 34, 1,
                                 [RoutePath("0.0.0.0",
                                            0xffffffff,
                                            nh_via_label=32,
                                            labels=[44, 45])])
        route_34_eos.add_vpp_config()

        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [34])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled_ip4(self.pg0, rx, tx, [33, 44, 45])

        #
        # A recursive non-EOS x-connect, which resolves through another x-connect
        #
        route_34_neos = MplsRoute(self, 34, 0,
                                  [RoutePath("0.0.0.0",
                                             0xffffffff,
                                             nh_via_label=32,
                                             labels=[44, 46])])
        route_34_neos.add_vpp_config()

        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [34, 99])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        # it's the 2nd (counting from 0) lael in the stack that is swapped
        self.verify_capture_labelled(self.pg0, rx, tx, [33, 44, 46, 99], num=2)

        #
        # an recursive IP route that resolves through the recursive non-eos x-connect
        #
        ip_10_0_0_1 = IpRoute(self, "10.0.0.1", 32,
                              [RoutePath("0.0.0.0",
                                         0xffffffff,
                                         nh_via_label=34,
                                         labels=[55])])
        ip_10_0_0_1.add_vpp_config()

        self.vapi.cli("clear trace")
        tx = self.create_stream_ip4(self.pg0, "10.0.0.1")
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled_ip4(self.pg0, rx, tx, [33, 44, 46, 55])

        ip_10_0_0_1.remove_vpp_config()
        route_34_neos.remove_vpp_config()
        route_34_eos.remove_vpp_config()
        route_33_neos.remove_vpp_config()
        route_33_eos.remove_vpp_config()
        route_32_neos.remove_vpp_config()
        route_32_eos.remove_vpp_config()

    def test_bind(self):
        """ MPLS Local Label Binding test """

        #
        # Add a non-recursive route with a single out label
        #
        route_10_0_0_1 = IpRoute(self, "10.0.0.1", 32,
                                 [RoutePath(self.pg0.remote_ip4,
                                            self.pg0.sw_if_index,
                                            labels=[45])])
        route_10_0_0_1.add_vpp_config()

        # bind a local label to the route
        binding = MplsIpBind(self, 44, "10.0.0.1", 32)
        binding.add_vpp_config()

        # non-EOS stream
        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [44, 99])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled(self.pg0, rx, tx, [45, 99])

        # EOS stream
        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [44])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled(self.pg0, rx, tx, [45])

        # IP stream
        self.vapi.cli("clear trace")
        tx = self.create_stream_ip4(self.pg0, "10.0.0.1")
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled_ip4(self.pg0, rx, tx, [45])

        #
        # cleanup
        #
        binding.remove_vpp_config()
        route_10_0_0_1.remove_vpp_config()

    def test_imposition(self):
        """ MPLS label imposition test """

        #
        # Add a non-recursive route with a single out label
        #
        route_10_0_0_1 = IpRoute(self, "10.0.0.1", 32,
                                 [RoutePath(self.pg0.remote_ip4,
                                            self.pg0.sw_if_index,
                                            labels=[32])])
        route_10_0_0_1.add_vpp_config()

        #
        # a stream that matches the route for 10.0.0.1
        # PG0 is in the default table
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_ip4(self.pg0, "10.0.0.1")
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled_ip4(self.pg0, rx, tx, [32])

        #
        # Add a non-recursive route with a 3 out labels
        #
        route_10_0_0_2 = IpRoute(self, "10.0.0.2", 32,
                                 [RoutePath(self.pg0.remote_ip4,
                                            self.pg0.sw_if_index,
                                            labels=[32, 33, 34])])
        route_10_0_0_2.add_vpp_config()

        #
        # a stream that matches the route for 10.0.0.1
        # PG0 is in the default table
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_ip4(self.pg0, "10.0.0.2")
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled_ip4(self.pg0, rx, tx, [32, 33, 34])

        #
        # add a recursive path, with ouput label, via the 1 label route
        #
        route_11_0_0_1 = IpRoute(self, "11.0.0.1", 32,
                                 [RoutePath("10.0.0.1",
                                            0xffffffff,
                                            labels=[44])])
        route_11_0_0_1.add_vpp_config()

        #
        # a stream that matches the route for 11.0.0.1, should pick up
        # the label stack for 11.0.0.1 and 10.0.0.1
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_ip4(self.pg0, "11.0.0.1")
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled_ip4(self.pg0, rx, tx, [32, 44])

        #
        # add a recursive path, with 2 labels, via the 3 label route
        #
        route_11_0_0_2 = IpRoute(self, "11.0.0.2", 32,
                                 [RoutePath("10.0.0.2",
                                            0xffffffff,
                                            labels=[44, 45])])
        route_11_0_0_2.add_vpp_config()

        #
        # a stream that matches the route for 11.0.0.1, should pick up
        # the label stack for 11.0.0.1 and 10.0.0.1
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_ip4(self.pg0, "11.0.0.2")
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_labelled_ip4(
            self.pg0, rx, tx, [32, 33, 34, 44, 45])

        #
        # cleanup
        #
        route_11_0_0_2.remove_vpp_config()
        route_11_0_0_1.remove_vpp_config()
        route_10_0_0_2.remove_vpp_config()
        route_10_0_0_1.remove_vpp_config()

    def test_tunnel(self):
        """ MPLS Tunnel Tests """

        #
        # Create a tunnel with a single out label
        #
        nh_addr = socket.inet_pton(socket.AF_INET, self.pg0.remote_ip4)

        reply = self.vapi.mpls_tunnel_add_del(0xffffffff,  # don't know the if index yet
                                              1,  # IPv4 next-hop
                                              nh_addr,
                                              self.pg0.sw_if_index,
                                              0,  # next-hop-table-id
                                              1,  # next-hop-weight
                                              2,  # num-out-labels,
                                              [44, 46])
        self.vapi.sw_interface_set_flags(reply.sw_if_index, admin_up_down=1)

        #
        # add an unlabelled route through the new tunnel
        #
        dest_addr = socket.inet_pton(socket.AF_INET, "10.0.0.3")
        nh_addr = socket.inet_pton(socket.AF_INET, "0.0.0.0")
        dest_addr_len = 32

        self.vapi.ip_add_del_route(dest_addr,
                                   dest_addr_len,
                                   nh_addr,  # all zeros next-hop - tunnel is p2p
                                   reply.sw_if_index,  # sw_if_index of the new tunnel
                                   0,  # table-id
                                   0,  # next-hop-table-id
                                   1,  # next-hop-weight
                                   0,  # num-out-labels,
                                   [])  # out-label

        self.vapi.cli("clear trace")
        tx = self.create_stream_ip4(self.pg0, "10.0.0.3")
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_tunneled_ip4(self.pg0, rx, tx, [44, 46])

    def test_v4_exp_null(self):
        """ MPLS V4 Explicit NULL test """

        #
        # The first test case has an MPLS TTL of 0
        # all packet should be dropped
        #
        tx = self.create_stream_labelled_ip4(self.pg0, [0], 0)
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()

        try:
            self.assertEqual(0, len(rx))
        except:
            self.logger.error("MPLS TTL=0 packets forwarded")
            self.logger.error(ppp("", rx))
            raise

        #
        # a stream with a non-zero MPLS TTL
        # PG0 is in the default table
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg0, [0])
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_ip4(self.pg0, rx, tx)

        #
        # a stream with a non-zero MPLS TTL
        # PG1 is in table 1
        # we are ensuring the post-pop lookup occurs in the VRF table
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip4(self.pg1, [0])
        self.pg1.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg1.get_capture()
        self.verify_capture_ip4(self.pg0, rx, tx)

    def test_v6_exp_null(self):
        """ MPLS V6 Explicit NULL test """

        #
        # a stream with a non-zero MPLS TTL
        # PG0 is in the default table
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip6(self.pg0, 2, 2)
        self.pg0.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg0.get_capture()
        self.verify_capture_ip6(self.pg0, rx, tx)

        #
        # a stream with a non-zero MPLS TTL
        # PG1 is in table 1
        # we are ensuring the post-pop lookup occurs in the VRF table
        #
        self.vapi.cli("clear trace")
        tx = self.create_stream_labelled_ip6(self.pg1, 2, 2)
        self.pg1.add_stream(tx)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg1.get_capture()
        self.verify_capture_ip6(self.pg0, rx, tx)


if __name__ == '__main__':
    unittest.main(testRunner=VppTestRunner)