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#!/usr/bin/env python3

import unittest

from framework import VppTestCase, VppTestRunner, running_extended_tests
from vpp_ip import DpoProto
from vpp_ip_route import VppIpRoute, VppRoutePath, \
    VppMplsTable, VppIpMRoute, VppMRoutePath, VppIpTable, \
    MPLS_LABEL_INVALID, \
    VppMplsLabel, FibPathProto, FibPathType
from vpp_bier import BIER_HDR_PAYLOAD, VppBierImp, VppBierDispEntry, \
    VppBierDispTable, VppBierTable, VppBierTableID, VppBierRoute
from vpp_udp_encap import VppUdpEncap
from vpp_papi import VppEnum

import scapy.compat
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 scapy.contrib.bier import BIER, BIERLength, BIFT

NUM_PKTS = 67


class TestBFIB(VppTestCase):
    """ BIER FIB Test Case """

    def test_bfib(self):
        """ BFIB Unit Tests """
        error = self.vapi.cli("test bier")

        if error:
            self.logger.critical(error)
        self.assertNotIn("Failed", error)


class TestBier(VppTestCase):
    """ BIER Test Case """

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

        # create 2 pg interfaces
        self.create_pg_interfaces(range(3))

        # create the default MPLS table
        self.tables = []
        tbl = VppMplsTable(self, 0)
        tbl.add_vpp_config()
        self.tables.append(tbl)

        tbl = VppIpTable(self, 10)
        tbl.add_vpp_config()
        self.tables.append(tbl)

        # setup both interfaces
        for i in self.pg_interfaces:
            if i == self.pg2:
                i.set_table_ip4(10)
            i.admin_up()
            i.config_ip4()
            i.resolve_arp()
            i.enable_mpls()

    def tearDown(self):
        for i in self.pg_interfaces:
            i.disable_mpls()
            i.unconfig_ip4()
            i.set_table_ip4(0)
            i.admin_down()
        super(TestBier, self).tearDown()

    def bier_midpoint(self, hdr_len_id, n_bytes, max_bp):
        """BIER midpoint"""

        #
        # Add a BIER table for sub-domain 0, set 0, and BSL 256
        #
        bti = VppBierTableID(0, 0, hdr_len_id)
        bt = VppBierTable(self, bti, 77)
        bt.add_vpp_config()

        #
        # A packet with no bits set gets dropped
        #
        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
             MPLS(label=77, ttl=255) /
             BIER(length=hdr_len_id) /
             IPv6(src=self.pg0.remote_ip6, dst=self.pg0.remote_ip6) /
             UDP(sport=1234, dport=1234) /
             Raw())
        pkts = [p]

        self.send_and_assert_no_replies(self.pg0, pkts,
                                        "Empty Bit-String")

        #
        # Add a BIER route for each bit-position in the table via a different
        # next-hop. Testing whether the BIER walk and replicate forwarding
        # function works for all bit posisitons.
        #
        nh_routes = []
        bier_routes = []
        for i in range(1, max_bp+1):
            nh = "10.0.%d.%d" % (i / 255, i % 255)
            nh_routes.append(
                VppIpRoute(self, nh, 32,
                           [VppRoutePath(self.pg1.remote_ip4,
                                         self.pg1.sw_if_index,
                                         labels=[VppMplsLabel(2000+i)])]))
            nh_routes[-1].add_vpp_config()

            bier_routes.append(
                VppBierRoute(self, bti, i,
                             [VppRoutePath(nh, 0xffffffff,
                                           labels=[VppMplsLabel(100+i)])]))
            bier_routes[-1].add_vpp_config()

        #
        # A packet with all bits set gets replicated once for each bit
        #
        pkt_sizes = [64, 1400]

        for pkt_size in pkt_sizes:
            p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
                 MPLS(label=77, ttl=255) /
                 BIER(length=hdr_len_id,
                      BitString=scapy.compat.chb(255)*n_bytes) /
                 IPv6(src=self.pg0.remote_ip6, dst=self.pg0.remote_ip6) /
                 UDP(sport=1234, dport=1234) /
                 Raw(scapy.compat.chb(5) * pkt_size))
            pkts = p

            self.pg0.add_stream(pkts)
            self.pg_enable_capture(self.pg_interfaces)
            self.pg_start()

            rx = self.pg1.get_capture(max_bp)

            for rxp in rx:
                #
                # The packets are not required to be sent in bit-position order
                # when we setup the routes above we used the bit-position to
                # construct the out-label. so use that here to determine the BP
                #
                olabel = rxp[MPLS]
                bp = olabel.label - 2000

                blabel = olabel[MPLS].payload
                self.assertEqual(blabel.label, 100+bp)
                self.assertEqual(blabel.ttl, 254)

                bier_hdr = blabel[MPLS].payload

                self.assertEqual(bier_hdr.id, 5)
                self.assertEqual(bier_hdr.version, 0)
                self.assertEqual(bier_hdr.length, hdr_len_id)
                self.assertEqual(bier_hdr.entropy, 0)
                self.assertEqual(bier_hdr.OAM, 0)
                self.assertEqual(bier_hdr.RSV, 0)
                self.assertEqual(bier_hdr.DSCP, 0)
                self.assertEqual(bier_hdr.Proto, 5)

                # The bit-string should consist only of the BP given by i.
                byte_array = [b'\0'] * (n_bytes)
                byte_val = scapy.compat.chb(1 << (bp - 1) % 8)
                byte_pos = n_bytes - (((bp - 1) // 8) + 1)
                byte_array[byte_pos] = byte_val
                bitstring = b''.join(byte_array)

                self.assertEqual(len(bitstring), len(bier_hdr.BitString))
                self.assertEqual(bitstring, bier_hdr.BitString)

        #
        # cleanup. not strictly necessary, but it's much quicker this way
        # because the bier_fib_dump and ip_fib_dump will be empty when the
        # auto-cleanup kicks in
        #
        for br in bier_routes:
            br.remove_vpp_config()
        for nhr in nh_routes:
            nhr.remove_vpp_config()

    @unittest.skipUnless(running_extended_tests, "part of extended tests")
    def test_bier_midpoint_1024(self):
        """BIER midpoint BSL:1024"""
        self.bier_midpoint(BIERLength.BIER_LEN_1024, 128, 1024)

    @unittest.skipUnless(running_extended_tests, "part of extended tests")
    def test_bier_midpoint_512(self):
        """BIER midpoint BSL:512"""
        self.bier_midpoint(BIERLength.BIER_LEN_512, 64, 512)

    @unittest.skipUnless(running_extended_tests, "part of extended tests")
    def test_bier_midpoint_256(self):
        """BIER midpoint BSL:256"""
        self.bier_midpoint(BIERLength.BIER_LEN_256, 32, 256)

    @unittest.skipUnless(running_extended_tests, "part of extended tests")
    def test_bier_midpoint_128(self):
        """BIER midpoint BSL:128"""
        self.bier_midpoint(BIERLength.BIER_LEN_128, 16, 128)

    def test_bier_midpoint_64(self):
        """BIER midpoint BSL:64"""
        self.bier_midpoint(BIERLength.BIER_LEN_64, 8, 64)

    def test_bier_load_balance(self):
        """BIER load-balance"""

        #
        # Add a BIER table for sub-domain 0, set 0, and BSL 256
        #
        bti = VppBierTableID(0, 0, BIERLength.BIER_LEN_64)
        bt = VppBierTable(self, bti, 77)
        bt.add_vpp_config()

        #
        # packets with varying entropy
        #
        pkts = []
        for ii in range(257):
            pkts.append((Ether(dst=self.pg0.local_mac,
                               src=self.pg0.remote_mac) /
                         MPLS(label=77, ttl=255) /
                         BIER(length=BIERLength.BIER_LEN_64,
                              entropy=ii,
                              BitString=scapy.compat.chb(255)*16) /
                         IPv6(src=self.pg0.remote_ip6,
                              dst=self.pg0.remote_ip6) /
                         UDP(sport=1234, dport=1234) /
                         Raw()))

        #
        # 4 next hops
        #
        nhs = [{'ip': "10.0.0.1", 'label': 201},
               {'ip': "10.0.0.2", 'label': 202},
               {'ip': "10.0.0.3", 'label': 203},
               {'ip': "10.0.0.4", 'label': 204}]

        for nh in nhs:
            ipr = VppIpRoute(
                self, nh['ip'], 32,
                [VppRoutePath(self.pg1.remote_ip4,
                              self.pg1.sw_if_index,
                              labels=[VppMplsLabel(nh['label'])])])
            ipr.add_vpp_config()

        bier_route = VppBierRoute(
            self, bti, 1,
            [VppRoutePath(nhs[0]['ip'], 0xffffffff,
                          labels=[VppMplsLabel(101)]),
             VppRoutePath(nhs[1]['ip'], 0xffffffff,
                          labels=[VppMplsLabel(101)])])
        bier_route.add_vpp_config()

        rx = self.send_and_expect(self.pg0, pkts, self.pg1)

        #
        # we should have recieved a packet from each neighbor
        #
        for nh in nhs[:2]:
            self.assertTrue(sum(p[MPLS].label == nh['label'] for p in rx))

        #
        # add the other paths
        #
        bier_route.update_paths(
            [VppRoutePath(nhs[0]['ip'], 0xffffffff,
                          labels=[VppMplsLabel(101)]),
             VppRoutePath(nhs[1]['ip'], 0xffffffff,
                          labels=[VppMplsLabel(101)]),
             VppRoutePath(nhs[2]['ip'], 0xffffffff,
                          labels=[VppMplsLabel(101)]),
             VppRoutePath(nhs[3]['ip'], 0xffffffff,
                          labels=[VppMplsLabel(101)])])

        rx = self.send_and_expect(self.pg0, pkts, self.pg1)

        for nh in nhs:
            self.assertTrue(sum(p[MPLS].label == nh['label'] for p in rx))

        #
        # remove first two paths
        #
        bier_route.remove_path(VppRoutePath(nhs[0]['ip'], 0xffffffff,
                                            labels=[VppMplsLabel(101)]))
        bier_route.remove_path(VppRoutePath(nhs[1]['ip'], 0xffffffff,
                                            labels=[VppMplsLabel(101)]))

        rx = self.send_and_expect(self.pg0, pkts, self.pg1)
        for nh in nhs[2:]:
            self.assertTrue(sum(p[MPLS].label == nh['label'] for p in rx))

        #
        # remove the last of the paths, deleteing the entry
        #
        bier_route.remove_all_paths()

        self.send_and_assert_no_replies(self.pg0, pkts)

    def test_bier_head(self):
        """BIER head"""

        MRouteItfFlags = VppEnum.vl_api_mfib_itf_flags_t
        MRouteEntryFlags = VppEnum.vl_api_mfib_entry_flags_t

        #
        # Add a BIER table for sub-domain 0, set 0, and BSL 256
        #
        bti = VppBierTableID(0, 0, BIERLength.BIER_LEN_256)
        bt = VppBierTable(self, bti, 77)
        bt.add_vpp_config()

        #
        # 2 bit positions via two next hops
        #
        nh1 = "10.0.0.1"
        nh2 = "10.0.0.2"
        ip_route_1 = VppIpRoute(self, nh1, 32,
                                [VppRoutePath(self.pg1.remote_ip4,
                                              self.pg1.sw_if_index,
                                              labels=[VppMplsLabel(2001)])])
        ip_route_2 = VppIpRoute(self, nh2, 32,
                                [VppRoutePath(self.pg1.remote_ip4,
                                              self.pg1.sw_if_index,
                                              labels=[VppMplsLabel(2002)])])
        ip_route_1.add_vpp_config()
        ip_route_2.add_vpp_config()

        bier_route_1 = VppBierRoute(self, bti, 1,
                                    [VppRoutePath(nh1, 0xffffffff,
                                                  labels=[VppMplsLabel(101)])])
        bier_route_2 = VppBierRoute(self, bti, 2,
                                    [VppRoutePath(nh2, 0xffffffff,
                                                  labels=[VppMplsLabel(102)])])
        bier_route_1.add_vpp_config()
        bier_route_2.add_vpp_config()

        #
        # An imposition object with both bit-positions set
        #
        bi = VppBierImp(self, bti, 333, scapy.compat.chb(0x3) * 32)
        bi.add_vpp_config()

        #
        # Add a multicast route that will forward into the BIER doamin
        #
        route_ing_232_1_1_1 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.1", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            paths=[VppMRoutePath(self.pg0.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_ACCEPT),
                   VppMRoutePath(0xffffffff,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD,
                                 proto=FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                 type=FibPathType.FIB_PATH_TYPE_BIER_IMP,
                                 bier_imp=bi.bi_index)])
        route_ing_232_1_1_1.add_vpp_config()

        #
        # inject an IP packet. We expect it to be BIER encapped and
        # replicated.
        #
        p = (Ether(dst=self.pg0.local_mac,
                   src=self.pg0.remote_mac) /
             IP(src="1.1.1.1", dst="232.1.1.1") /
             UDP(sport=1234, dport=1234))

        self.pg0.add_stream([p])
        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg1.get_capture(2)

        #
        # Encap Stack is; eth, MPLS, MPLS, BIER
        #
        igp_mpls = rx[0][MPLS]
        self.assertEqual(igp_mpls.label, 2001)
        self.assertEqual(igp_mpls.ttl, 64)
        self.assertEqual(igp_mpls.s, 0)
        bier_mpls = igp_mpls[MPLS].payload
        self.assertEqual(bier_mpls.label, 101)
        self.assertEqual(bier_mpls.ttl, 64)
        self.assertEqual(bier_mpls.s, 1)
        self.assertEqual(rx[0][BIER].length, 2)

        igp_mpls = rx[1][MPLS]
        self.assertEqual(igp_mpls.label, 2002)
        self.assertEqual(igp_mpls.ttl, 64)
        self.assertEqual(igp_mpls.s, 0)
        bier_mpls = igp_mpls[MPLS].payload
        self.assertEqual(bier_mpls.label, 102)
        self.assertEqual(bier_mpls.ttl, 64)
        self.assertEqual(bier_mpls.s, 1)
        self.assertEqual(rx[0][BIER].length, 2)

    def test_bier_tail(self):
        """BIER Tail"""

        MRouteItfFlags = VppEnum.vl_api_mfib_itf_flags_t
        MRouteEntryFlags = VppEnum.vl_api_mfib_entry_flags_t

        #
        # Add a BIER table for sub-domain 0, set 0, and BSL 256
        #
        bti = VppBierTableID(0, 0, BIERLength.BIER_LEN_256)
        bt = VppBierTable(self, bti, 77)
        bt.add_vpp_config()

        #
        # disposition table
        #
        bdt = VppBierDispTable(self, 8)
        bdt.add_vpp_config()

        #
        # BIER route in table that's for-us
        #
        bier_route_1 = VppBierRoute(
            self, bti, 1,
            [VppRoutePath("0.0.0.0",
                          0xffffffff,
                          proto=FibPathProto.FIB_PATH_NH_PROTO_BIER,
                          nh_table_id=8)])
        bier_route_1.add_vpp_config()

        #
        # An entry in the disposition table
        #
        bier_de_1 = VppBierDispEntry(self, bdt.id, 99,
                                     BIER_HDR_PAYLOAD.BIER_HDR_PROTO_IPV4,
                                     FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                     "0.0.0.0", 0, rpf_id=8192)
        bier_de_1.add_vpp_config()

        #
        # A multicast route to forward post BIER disposition
        #
        route_eg_232_1_1_1 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.1", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            paths=[VppMRoutePath(self.pg1.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD)])
        route_eg_232_1_1_1.add_vpp_config()
        route_eg_232_1_1_1.update_rpf_id(8192)

        #
        # A packet with all bits set gets spat out to BP:1
        #
        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
             MPLS(label=77, ttl=255) /
             BIER(length=BIERLength.BIER_LEN_256,
                  BitString=scapy.compat.chb(255)*32,
                  BFRID=99) /
             IP(src="1.1.1.1", dst="232.1.1.1") /
             UDP(sport=1234, dport=1234) /
             Raw())

        self.send_and_expect(self.pg0, [p], self.pg1)

        #
        # A packet that does not match the Disposition entry gets dropped
        #
        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
             MPLS(label=77, ttl=255) /
             BIER(length=BIERLength.BIER_LEN_256,
                  BitString=scapy.compat.chb(255)*32,
                  BFRID=77) /
             IP(src="1.1.1.1", dst="232.1.1.1") /
             UDP(sport=1234, dport=1234) /
             Raw())
        self.send_and_assert_no_replies(self.pg0, p*2,
                                        "no matching disposition entry")

        #
        # Add the default route to the disposition table
        #
        bier_de_2 = VppBierDispEntry(self, bdt.id, 0,
                                     BIER_HDR_PAYLOAD.BIER_HDR_PROTO_IPV4,
                                     FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                     "0.0.0.0", 0, rpf_id=8192)
        bier_de_2.add_vpp_config()

        #
        # now the previous packet is forwarded
        #
        self.send_and_expect(self.pg0, [p], self.pg1)

        #
        # A multicast route to forward post BIER disposition that needs
        # a check against sending back into the BIER core
        #
        bi = VppBierImp(self, bti, 333, scapy.compat.chb(0x3) * 32)
        bi.add_vpp_config()

        route_eg_232_1_1_2 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.2", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            paths=[VppMRoutePath(0xffffffff,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD,
                                 proto=DpoProto.DPO_PROTO_BIER,
                                 type=FibPathType.FIB_PATH_TYPE_BIER_IMP,
                                 bier_imp=bi.bi_index),
                   VppMRoutePath(self.pg1.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD)])
        route_eg_232_1_1_2.add_vpp_config()
        route_eg_232_1_1_2.update_rpf_id(8192)

        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
             MPLS(label=77, ttl=255) /
             BIER(length=BIERLength.BIER_LEN_256,
                  BitString=scapy.compat.chb(255)*32,
                  BFRID=77) /
             IP(src="1.1.1.1", dst="232.1.1.2") /
             UDP(sport=1234, dport=1234) /
             Raw())
        self.send_and_expect(self.pg0, [p], self.pg1)

    def bier_e2e(self, hdr_len_id, n_bytes, max_bp):
        """ BIER end-to-end"""

        MRouteItfFlags = VppEnum.vl_api_mfib_itf_flags_t
        MRouteEntryFlags = VppEnum.vl_api_mfib_entry_flags_t

        #
        # Add a BIER table for sub-domain 0, set 0, and BSL 256
        #
        bti = VppBierTableID(0, 0, hdr_len_id)
        bt = VppBierTable(self, bti, 77)
        bt.add_vpp_config()

        lowest = [b'\0'] * (n_bytes)
        lowest[-1] = scapy.compat.chb(1)
        highest = [b'\0'] * (n_bytes)
        highest[0] = scapy.compat.chb(128)

        #
        # Impostion Sets bit strings
        #
        bi_low = VppBierImp(self, bti, 333, lowest)
        bi_low.add_vpp_config()
        bi_high = VppBierImp(self, bti, 334, highest)
        bi_high.add_vpp_config()

        #
        # Add a multicast route that will forward into the BIER doamin
        #
        route_ing_232_1_1_1 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.1", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            paths=[VppMRoutePath(self.pg0.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_ACCEPT),
                   VppMRoutePath(0xffffffff,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD,
                                 proto=FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                 type=FibPathType.FIB_PATH_TYPE_BIER_IMP,
                                 bier_imp=bi_low.bi_index)])
        route_ing_232_1_1_1.add_vpp_config()
        route_ing_232_1_1_2 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.2", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            paths=[VppMRoutePath(self.pg0.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_ACCEPT),
                   VppMRoutePath(0xffffffff,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD,
                                 proto=FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                 type=FibPathType.FIB_PATH_TYPE_BIER_IMP,
                                 bier_imp=bi_high.bi_index)])
        route_ing_232_1_1_2.add_vpp_config()

        #
        # disposition table 8
        #
        bdt = VppBierDispTable(self, 8)
        bdt.add_vpp_config()

        #
        # BIER routes in table that are for-us, resolving through
        # disp table 8.
        #
        bier_route_1 = VppBierRoute(
            self, bti, 1,
            [VppRoutePath("0.0.0.0",
                          0xffffffff,
                          proto=FibPathProto.FIB_PATH_NH_PROTO_BIER,
                          nh_table_id=8)])
        bier_route_1.add_vpp_config()
        bier_route_max = VppBierRoute(
            self, bti, max_bp,
            [VppRoutePath("0.0.0.0",
                          0xffffffff,
                          proto=FibPathProto.FIB_PATH_NH_PROTO_BIER,
                          nh_table_id=8)])
        bier_route_max.add_vpp_config()

        #
        # An entry in the disposition table for sender 333
        #  lookup in VRF 10
        #
        bier_de_1 = VppBierDispEntry(self, bdt.id, 333,
                                     BIER_HDR_PAYLOAD.BIER_HDR_PROTO_IPV4,
                                     FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                     "0.0.0.0", 10, rpf_id=8192)
        bier_de_1.add_vpp_config()
        bier_de_1 = VppBierDispEntry(self, bdt.id, 334,
                                     BIER_HDR_PAYLOAD.BIER_HDR_PROTO_IPV4,
                                     FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                     "0.0.0.0", 10, rpf_id=8193)
        bier_de_1.add_vpp_config()

        #
        # Add a multicast routes that will forward the traffic
        # post-disposition
        #
        route_eg_232_1_1_1 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.1", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            table_id=10,
            paths=[VppMRoutePath(self.pg1.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD)])
        route_eg_232_1_1_1.add_vpp_config()
        route_eg_232_1_1_1.update_rpf_id(8192)
        route_eg_232_1_1_2 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.2", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            table_id=10,
            paths=[VppMRoutePath(self.pg1.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD)])
        route_eg_232_1_1_2.add_vpp_config()
        route_eg_232_1_1_2.update_rpf_id(8193)

        #
        # inject a packet in VRF-0. We expect it to be BIER encapped,
        # replicated, then hit the disposition and be forwarded
        # out of VRF 10, i.e. on pg1
        #
        p = (Ether(dst=self.pg0.local_mac,
                   src=self.pg0.remote_mac) /
             IP(src="1.1.1.1", dst="232.1.1.1") /
             UDP(sport=1234, dport=1234) /
             Raw(scapy.compat.chb(5) * 32))

        rx = self.send_and_expect(self.pg0, p*NUM_PKTS, self.pg1)

        self.assertEqual(rx[0][IP].src, "1.1.1.1")
        self.assertEqual(rx[0][IP].dst, "232.1.1.1")

        p = (Ether(dst=self.pg0.local_mac,
                   src=self.pg0.remote_mac) /
             IP(src="1.1.1.1", dst="232.1.1.2") /
             UDP(sport=1234, dport=1234) /
             Raw(scapy.compat.chb(5) * 512))

        rx = self.send_and_expect(self.pg0, p*NUM_PKTS, self.pg1)
        self.assertEqual(rx[0][IP].src, "1.1.1.1")
        self.assertEqual(rx[0][IP].dst, "232.1.1.2")

    @unittest.skipUnless(running_extended_tests, "part of extended tests")
    def test_bier_e2e_1024(self):
        """ BIER end-to-end BSL:1024"""
        self.bier_e2e(BIERLength.BIER_LEN_1024, 128, 1024)

    @unittest.skipUnless(running_extended_tests, "part of extended tests")
    def test_bier_e2e_512(self):
        """ BIER end-to-end BSL:512"""
        self.bier_e2e(BIERLength.BIER_LEN_512, 64, 512)

    @unittest.skipUnless(running_extended_tests, "part of extended tests")
    def test_bier_e2e_256(self):
        """ BIER end-to-end BSL:256"""
        self.bier_e2e(BIERLength.BIER_LEN_256, 32, 256)

    @unittest.skipUnless(running_extended_tests, "part of extended tests")
    def test_bier_e2e_128(self):
        """ BIER end-to-end BSL:128"""
        self.bier_e2e(BIERLength.BIER_LEN_128, 16, 128)

    def test_bier_e2e_64(self):
        """ BIER end-to-end BSL:64"""
        self.bier_e2e(BIERLength.BIER_LEN_64, 8, 64)

    def test_bier_head_o_udp(self):
        """BIER head over UDP"""

        MRouteItfFlags = VppEnum.vl_api_mfib_itf_flags_t
        MRouteEntryFlags = VppEnum.vl_api_mfib_entry_flags_t

        #
        # Add a BIER table for sub-domain 1, set 0, and BSL 256
        #
        bti = VppBierTableID(1, 0, BIERLength.BIER_LEN_256)
        bt = VppBierTable(self, bti, 77)
        bt.add_vpp_config()

        #
        # 1 bit positions via 1 next hops
        #
        nh1 = "10.0.0.1"
        ip_route = VppIpRoute(self, nh1, 32,
                              [VppRoutePath(self.pg1.remote_ip4,
                                            self.pg1.sw_if_index,
                                            labels=[VppMplsLabel(2001)])])
        ip_route.add_vpp_config()

        udp_encap = VppUdpEncap(self,
                                self.pg0.local_ip4,
                                nh1,
                                330, 8138)
        udp_encap.add_vpp_config()

        bier_route = VppBierRoute(
            self, bti, 1,
            [VppRoutePath("0.0.0.0",
                          0xFFFFFFFF,
                          type=FibPathType.FIB_PATH_TYPE_UDP_ENCAP,
                          next_hop_id=udp_encap.id)])
        bier_route.add_vpp_config()

        #
        # An 2 imposition objects with all bit-positions set
        # only use the second, but creating 2 tests with a non-zero
        # value index in the route add
        #
        bi = VppBierImp(self, bti, 333, scapy.compat.chb(0xff) * 32)
        bi.add_vpp_config()
        bi2 = VppBierImp(self, bti, 334, scapy.compat.chb(0xff) * 32)
        bi2.add_vpp_config()

        #
        # Add a multicast route that will forward into the BIER doamin
        #
        route_ing_232_1_1_1 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.1", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            paths=[VppMRoutePath(self.pg0.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_ACCEPT),
                   VppMRoutePath(0xffffffff,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD,
                                 proto=FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                 type=FibPathType.FIB_PATH_TYPE_BIER_IMP,
                                 bier_imp=bi2.bi_index)])
        route_ing_232_1_1_1.add_vpp_config()

        #
        # inject a packet an IP. We expect it to be BIER and UDP encapped,
        #
        p = (Ether(dst=self.pg0.local_mac,
                   src=self.pg0.remote_mac) /
             IP(src="1.1.1.1", dst="232.1.1.1") /
             UDP(sport=1234, dport=1234))

        self.pg0.add_stream([p])
        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg1.get_capture(1)

        #
        # Encap Stack is, eth, IP, UDP, BIFT, BIER
        #
        self.assertEqual(rx[0][IP].src, self.pg0.local_ip4)
        self.assertEqual(rx[0][IP].dst, nh1)
        self.assertEqual(rx[0][UDP].sport, 330)
        self.assertEqual(rx[0][UDP].dport, 8138)
        self.assertEqual(rx[0][BIFT].bsl, BIERLength.BIER_LEN_256)
        self.assertEqual(rx[0][BIFT].sd, 1)
        self.assertEqual(rx[0][BIFT].set, 0)
        self.assertEqual(rx[0][BIFT].ttl, 64)
        self.assertEqual(rx[0][BIER].length, 2)

    def test_bier_tail_o_udp(self):
        """BIER Tail over UDP"""

        MRouteItfFlags = VppEnum.vl_api_mfib_itf_flags_t
        MRouteEntryFlags = VppEnum.vl_api_mfib_entry_flags_t

        #
        # Add a BIER table for sub-domain 0, set 0, and BSL 256
        #
        bti = VppBierTableID(1, 0, BIERLength.BIER_LEN_256)
        bt = VppBierTable(self, bti, MPLS_LABEL_INVALID)
        bt.add_vpp_config()

        #
        # disposition table
        #
        bdt = VppBierDispTable(self, 8)
        bdt.add_vpp_config()

        #
        # BIER route in table that's for-us
        #
        bier_route_1 = VppBierRoute(
            self, bti, 1,
            [VppRoutePath("0.0.0.0",
                          0xffffffff,
                          proto=FibPathProto.FIB_PATH_NH_PROTO_BIER,
                          nh_table_id=8)])
        bier_route_1.add_vpp_config()

        #
        # An entry in the disposition table
        #
        bier_de_1 = VppBierDispEntry(self, bdt.id, 99,
                                     BIER_HDR_PAYLOAD.BIER_HDR_PROTO_IPV4,
                                     FibPathProto.FIB_PATH_NH_PROTO_BIER,
                                     "0.0.0.0", 0, rpf_id=8192)
        bier_de_1.add_vpp_config()

        #
        # A multicast route to forward post BIER disposition
        #
        route_eg_232_1_1_1 = VppIpMRoute(
            self,
            "0.0.0.0",
            "232.1.1.1", 32,
            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
            paths=[VppMRoutePath(self.pg1.sw_if_index,
                                 MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD)])
        route_eg_232_1_1_1.add_vpp_config()
        route_eg_232_1_1_1.update_rpf_id(8192)

        #
        # A packet with all bits set gets spat out to BP:1
        #
        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
             IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4) /
             UDP(sport=333, dport=8138) /
             BIFT(sd=1, set=0, bsl=2, ttl=255) /
             BIER(length=BIERLength.BIER_LEN_256,
                  BitString=scapy.compat.chb(255)*32,
                  BFRID=99) /
             IP(src="1.1.1.1", dst="232.1.1.1") /
             UDP(sport=1234, dport=1234) /
             Raw())

        rx = self.send_and_expect(self.pg0, [p], self.pg1)


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