test/test_map.py

#!/usr/bin/env python3

import ipaddress
import unittest

from framework import VppTestCase, VppTestRunner
from vpp_ip import DpoProto
from vpp_ip_route import VppIpRoute, VppRoutePath
from util import fragment_rfc791, fragment_rfc8200

import scapy.compat
from scapy.layers.l2 import Ether
from scapy.packet import Raw
from scapy.layers.inet import IP, UDP, ICMP, TCP
from scapy.layers.inet6 import (
    IPv6,
    ICMPv6TimeExceeded,
    IPv6ExtHdrFragment,
    ICMPv6EchoRequest,
    ICMPv6DestUnreach,
)


class TestMAP(VppTestCase):
    """MAP Test Case"""

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

    @classmethod
    def tearDownClass(cls):
        super(TestMAP, cls).tearDownClass()

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

        # create 2 pg interfaces
        self.create_pg_interfaces(range(4))

        # pg0 is 'inside' IPv4
        self.pg0.admin_up()
        self.pg0.config_ip4()
        self.pg0.resolve_arp()
        self.pg0.generate_remote_hosts(2)
        self.pg0.configure_ipv4_neighbors()

        # pg1 is 'outside' IPv6
        self.pg1.admin_up()
        self.pg1.config_ip6()
        self.pg1.generate_remote_hosts(4)
        self.pg1.configure_ipv6_neighbors()

    def tearDown(self):
        super(TestMAP, self).tearDown()
        for i in self.pg_interfaces:
            i.unconfig_ip4()
            i.unconfig_ip6()
            i.admin_down()

    def send_and_assert_encapped(self, packets, ip6_src, ip6_dst, dmac=None):
        if not dmac:
            dmac = self.pg1.remote_mac

        self.pg0.add_stream(packets)

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

        capture = self.pg1.get_capture(len(packets))
        for rx, tx in zip(capture, packets):
            self.assertEqual(rx[Ether].dst, dmac)
            self.assertEqual(rx[IP].src, tx[IP].src)
            self.assertEqual(rx[IPv6].src, ip6_src)
            self.assertEqual(rx[IPv6].dst, ip6_dst)

    def send_and_assert_encapped_one(self, packet, ip6_src, ip6_dst, dmac=None):
        return self.send_and_assert_encapped([packet], ip6_src, ip6_dst, dmac)

    def test_api_map_domain_dump(self):
        map_dst = "2001::/64"
        map_src = "3000::1/128"
        client_pfx = "192.168.0.0/16"
        tag = "MAP-E tag."
        index = self.vapi.map_add_domain(
            ip4_prefix=client_pfx, ip6_prefix=map_dst, ip6_src=map_src, tag=tag
        ).index
        rv = self.vapi.map_domain_dump()

        # restore the state early so as to not impact subsequent tests.
        # If an assert fails, we will not get the chance to do it at the end.
        self.vapi.map_del_domain(index=index)

        self.assertGreater(len(rv), 0, "Expected output from 'map_domain_dump'")

        # typedefs are returned as ipaddress objects.
        # wrap results in str() ugh! to avoid the need to call unicode.
        self.assertEqual(str(rv[0].ip4_prefix), client_pfx)
        self.assertEqual(str(rv[0].ip6_prefix), map_dst)
        self.assertEqual(str(rv[0].ip6_src), map_src)

        self.assertEqual(rv[0].tag, tag, "output produced incorrect tag value.")

    def create_domains(self, ip4_pfx_str, ip6_pfx_str, ip6_src_str):
        ip4_pfx = ipaddress.ip_network(ip4_pfx_str)
        ip6_dst = ipaddress.ip_network(ip6_pfx_str)
        mod = ip4_pfx.num_addresses / 1024
        indicies = []
        for i in range(ip4_pfx.num_addresses):
            rv = self.vapi.map_add_domain(
                ip6_prefix=ip6_pfx_str,
                ip4_prefix=str(ip4_pfx[i]) + "/32",
                ip6_src=ip6_src_str,
            )
            indicies.append(rv.index)
        return indicies

    def test_api_map_domains_get(self):
        # Create a bunch of domains
        no_domains = 4096  # This must be large enough to ensure VPP suspends
        domains = self.create_domains("130.67.0.0/20", "2001::/32", "2001::1/128")
        self.assertEqual(len(domains), no_domains)

        d = []
        cursor = 0

        # Invalid cursor
        rv, details = self.vapi.map_domains_get(cursor=no_domains + 10)
        self.assertEqual(rv.retval, -7)

        # Delete a domain in the middle of walk
        rv, details = self.vapi.map_domains_get(cursor=0)
        self.assertEqual(rv.retval, -165)
        self.vapi.map_del_domain(index=rv.cursor)
        domains.remove(rv.cursor)

        # Continue at point of deleted cursor
        rv, details = self.vapi.map_domains_get(cursor=rv.cursor)
        self.assertIn(rv.retval, [0, -165])

        d = list(self.vapi.vpp.details_iter(self.vapi.map_domains_get))
        self.assertEqual(len(d), no_domains - 1)

        # Clean up
        for i in domains:
            self.vapi.map_del_domain(index=i)

    def test_map_e_udp(self):
        """MAP-E UDP"""

        #
        # Add a route to the MAP-BR
        #
        map_br_pfx = "2001::"
        map_br_pfx_len = 32
        map_route = VppIpRoute(
            self,
            map_br_pfx,
            map_br_pfx_len,
            [VppRoutePath(self.pg1.remote_ip6, self.pg1.sw_if_index)],
        )
        map_route.add_vpp_config()

        #
        # Add a domain that maps from pg0 to pg1
        #
        map_dst = "2001::/32"
        map_src = "3000::1/128"
        client_pfx = "192.168.0.0/16"
        map_translated_addr = "2001:0:101:7000:0:c0a8:101:7"
        tag = "MAP-E tag."
        self.vapi.map_add_domain(
            ip4_prefix=client_pfx,
            ip6_prefix=map_dst,
            ip6_src=map_src,
            ea_bits_len=20,
            psid_offset=4,
            psid_length=4,
            tag=tag,
        )

        self.vapi.map_param_set_security_check(enable=1, fragments=1)

        # Enable MAP on interface.
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg0.sw_if_index, is_translation=0
        )

        # Ensure MAP doesn't steal all packets!
        v4 = (
            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
            / IP(src=self.pg0.remote_ip4, dst=self.pg0.remote_ip4)
            / UDP(sport=20000, dport=10000)
            / Raw(b"\xa5" * 100)
        )
        rx = self.send_and_expect(self.pg0, v4 * 4, self.pg0)
        v4_reply = v4[1]
        v4_reply.ttl -= 1
        for p in rx:
            self.validate(p[1], v4_reply)

        #
        # Fire in a v4 packet that will be encapped to the BR
        #
        v4 = (
            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
            / IP(src=self.pg0.remote_ip4, dst="192.168.1.1")
            / UDP(sport=20000, dport=10000)
            / Raw(b"\xa5" * 100)
        )

        self.send_and_assert_encapped(v4 * 4, "3000::1", map_translated_addr)

        #
        # Verify reordered fragments are able to pass as well
        #
        v4 = (
            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
            / IP(id=1, src=self.pg0.remote_ip4, dst="192.168.1.1")
            / UDP(sport=20000, dport=10000)
            / Raw(b"\xa5" * 1000)
        )

        frags = fragment_rfc791(v4, 400)
        frags.reverse()

        self.send_and_assert_encapped(frags, "3000::1", map_translated_addr)

        # Enable MAP on interface.
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg1.sw_if_index, is_translation=0
        )

        # Ensure MAP doesn't steal all packets
        v6 = (
            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
            / IPv6(src=self.pg1.remote_ip6, dst=self.pg1.remote_ip6)
            / UDP(sport=20000, dport=10000)
            / Raw(b"\xa5" * 100)
        )
        rx = self.send_and_expect(self.pg1, v6 * 1, self.pg1)
        v6_reply = v6[1]
        v6_reply.hlim -= 1
        for p in rx:
            self.validate(p[1], v6_reply)

        #
        # Fire in a V6 encapped packet.
        # expect a decapped packet on the inside ip4 link
        #
        p = (
            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
            / IPv6(dst="3000::1", src=map_translated_addr)
            / IP(dst=self.pg0.remote_ip4, src="192.168.1.1")
            / UDP(sport=10000, dport=20000)
            / Raw(b"\xa5" * 100)
        )

        self.pg1.add_stream(p)

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

        rx = self.pg0.get_capture(1)
        rx = rx[0]

        self.assertFalse(rx.haslayer(IPv6))
        self.assertEqual(rx[IP].src, p[IP].src)
        self.assertEqual(rx[IP].dst, p[IP].dst)

        #
        # Verify encapped reordered fragments pass as well
        #
        p = (
            IP(id=1, dst=self.pg0.remote_ip4, src="192.168.1.1")
            / UDP(sport=10000, dport=20000)
            / Raw(b"\xa5" * 1500)
        )
        frags = fragment_rfc791(p, 400)
        frags.reverse()

        stream = (
            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
            / IPv6(dst="3000::1", src=map_translated_addr)
            / x
            for x in frags
        )

        self.pg1.add_stream(stream)

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

        rx = self.pg0.get_capture(len(frags))

        for r in rx:
            self.assertFalse(r.haslayer(IPv6))
            self.assertEqual(r[IP].src, p[IP].src)
            self.assertEqual(r[IP].dst, p[IP].dst)

        # Verify that fragments pass even if ipv6 layer is fragmented
        stream = (IPv6(dst="3000::1", src=map_translated_addr) / x for x in frags)

        v6_stream = [
            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) / x
            for i in range(len(frags))
            for x in fragment_rfc8200(
                IPv6(dst="3000::1", src=map_translated_addr) / frags[i], i, 200
            )
        ]

        self.pg1.add_stream(v6_stream)

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

        rx = self.pg0.get_capture(len(frags))

        for r in rx:
            self.assertFalse(r.haslayer(IPv6))
            self.assertEqual(r[IP].src, p[IP].src)
            self.assertEqual(r[IP].dst, p[IP].dst)

        #
        # Pre-resolve. No API for this!!
        #
        self.vapi.ppcli("map params pre-resolve ip6-nh 4001::1")

        self.send_and_assert_no_replies(self.pg0, v4, "resolved via default route")

        #
        # Add a route to 4001::1. Expect the encapped traffic to be
        # sent via that routes next-hop
        #
        pre_res_route = VppIpRoute(
            self,
            "4001::1",
            128,
            [VppRoutePath(self.pg1.remote_hosts[2].ip6, self.pg1.sw_if_index)],
        )
        pre_res_route.add_vpp_config()

        self.send_and_assert_encapped_one(
            v4, "3000::1", map_translated_addr, dmac=self.pg1.remote_hosts[2].mac
        )

        #
        # change the route to the pre-solved next-hop
        #
        pre_res_route.modify(
            [VppRoutePath(self.pg1.remote_hosts[3].ip6, self.pg1.sw_if_index)]
        )
        pre_res_route.add_vpp_config()

        self.send_and_assert_encapped_one(
            v4, "3000::1", map_translated_addr, dmac=self.pg1.remote_hosts[3].mac
        )

        #
        # cleanup. The test infra's object registry will ensure
        # the route is really gone and thus that the unresolve worked.
        #
        pre_res_route.remove_vpp_config()
        self.vapi.ppcli("map params pre-resolve del ip6-nh 4001::1")

    def test_map_e_inner_frag(self):
        """MAP-E Inner fragmentation"""

        #
        # Add a route to the MAP-BR
        #
        map_br_pfx = "2001::"
        map_br_pfx_len = 32
        map_route = VppIpRoute(
            self,
            map_br_pfx,
            map_br_pfx_len,
            [VppRoutePath(self.pg1.remote_ip6, self.pg1.sw_if_index)],
        )
        map_route.add_vpp_config()

        #
        # Add a domain that maps from pg0 to pg1
        #
        map_dst = "2001::/32"
        map_src = "3000::1/128"
        client_pfx = "192.168.0.0/16"
        map_translated_addr = "2001:0:101:7000:0:c0a8:101:7"
        tag = "MAP-E tag."
        self.vapi.map_add_domain(
            ip4_prefix=client_pfx,
            ip6_prefix=map_dst,
            ip6_src=map_src,
            ea_bits_len=20,
            psid_offset=4,
            psid_length=4,
            mtu=1000,
            tag=tag,
        )

        # Enable MAP on interface.
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg0.sw_if_index, is_translation=0
        )

        # Enable inner fragmentation
        self.vapi.map_param_set_fragmentation(inner=1)

        v4 = (
            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
            / IP(src=self.pg0.remote_ip4, dst="192.168.1.1")
            / UDP(sport=20000, dport=10000)
            / Raw(b"\xa5" * 1300)
        )

        self.pg_send(self.pg0, v4 * 1)
        rx = self.pg1.get_capture(2)

        # 1000-sizeof(ip6_header_t) = 960.
        frags = fragment_rfc791(v4[1], 960)
        frags[0].id = 0
        frags[1].id = 0
        frags[0].ttl -= 1
        frags[1].ttl -= 1
        frags[0].chksum = 0
        frags[1].chksum = 0

        v6_reply1 = IPv6(src="3000::1", dst=map_translated_addr, hlim=63) / frags[0]
        v6_reply2 = IPv6(src="3000::1", dst=map_translated_addr, hlim=63) / frags[1]
        rx[0][1].fl = 0
        rx[1][1].fl = 0
        rx[0][1][IP].id = 0
        rx[1][1][IP].id = 0
        rx[0][1][IP].chksum = 0
        rx[1][1][IP].chksum = 0

        self.validate(rx[0][1], v6_reply1)
        self.validate(rx[1][1], v6_reply2)

    def test_map_e_tcp_mss(self):
        """MAP-E TCP MSS"""

        #
        # Add a route to the MAP-BR
        #
        map_br_pfx = "2001::"
        map_br_pfx_len = 32
        map_route = VppIpRoute(
            self,
            map_br_pfx,
            map_br_pfx_len,
            [VppRoutePath(self.pg1.remote_ip6, self.pg1.sw_if_index)],
        )
        map_route.add_vpp_config()

        #
        # Add a domain that maps from pg0 to pg1
        #
        map_dst = "2001::/32"
        map_src = "3000::1/128"
        client_pfx = "192.168.0.0/16"
        map_translated_addr = "2001:0:101:5000:0:c0a8:101:5"
        tag = "MAP-E TCP tag."
        self.vapi.map_add_domain(
            ip4_prefix=client_pfx,
            ip6_prefix=map_dst,
            ip6_src=map_src,
            ea_bits_len=20,
            psid_offset=4,
            psid_length=4,
            tag=tag,
        )

        # Enable MAP on pg0 interface.
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg0.sw_if_index, is_translation=0
        )

        # Enable MAP on pg1 interface.
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg1.sw_if_index, is_translation=0
        )

        # TCP MSS clamping
        mss_clamp = 1300
        self.vapi.map_param_set_tcp(mss_clamp)

        #
        # Send a v4 packet that will be encapped.
        #
        p_ether = Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
        p_ip4 = IP(src=self.pg0.remote_ip4, dst="192.168.1.1")
        p_tcp = TCP(sport=20000, dport=30000, flags="S", options=[("MSS", 1455)])
        p4 = p_ether / p_ip4 / p_tcp

        self.pg1.add_stream(p4)
        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        rx = self.pg1.get_capture(1)
        rx = rx[0]

        self.assertTrue(rx.haslayer(IPv6))
        self.assertEqual(rx[IP].src, p4[IP].src)
        self.assertEqual(rx[IP].dst, p4[IP].dst)
        self.assertEqual(rx[IPv6].src, "3000::1")
        self.assertEqual(rx[TCP].options, TCP(options=[("MSS", mss_clamp)]).options)

    def validate(self, rx, expected):
        self.assertEqual(rx, expected.__class__(scapy.compat.raw(expected)))

    def validate_frag6(self, p6_frag, p_ip6_expected):
        self.assertFalse(p6_frag.haslayer(IP))
        self.assertTrue(p6_frag.haslayer(IPv6))
        self.assertTrue(p6_frag.haslayer(IPv6ExtHdrFragment))
        self.assertEqual(p6_frag[IPv6].src, p_ip6_expected.src)
        self.assertEqual(p6_frag[IPv6].dst, p_ip6_expected.dst)

    def validate_frag_payload_len6(self, rx, proto, payload_len_expected):
        payload_total = 0
        for p in rx:
            payload_total += p[IPv6].plen

        # First fragment has proto
        payload_total -= len(proto())

        # Every fragment has IPv6 fragment header
        payload_total -= len(IPv6ExtHdrFragment()) * len(rx)

        self.assertEqual(payload_total, payload_len_expected)

    def validate_frag4(self, p4_frag, p_ip4_expected):
        self.assertFalse(p4_frag.haslayer(IPv6))
        self.assertTrue(p4_frag.haslayer(IP))
        self.assertTrue(p4_frag[IP].frag != 0 or p4_frag[IP].flags.MF)
        self.assertEqual(p4_frag[IP].src, p_ip4_expected.src)
        self.assertEqual(p4_frag[IP].dst, p_ip4_expected.dst)

    def validate_frag_payload_len4(self, rx, proto, payload_len_expected):
        payload_total = 0
        for p in rx:
            payload_total += len(p[IP].payload)

        # First fragment has proto
        payload_total -= len(proto())

        self.assertEqual(payload_total, payload_len_expected)

    def payload(self, len):
        return "x" * len

    def test_map_t(self):
        """MAP-T"""

        #
        # Add a domain that maps from pg0 to pg1
        #
        map_dst = "2001:db8::/32"
        map_src = "1234:5678:90ab:cdef::/64"
        ip4_pfx = "192.168.0.0/24"
        tag = "MAP-T Tag."

        self.vapi.map_add_domain(
            ip6_prefix=map_dst,
            ip4_prefix=ip4_pfx,
            ip6_src=map_src,
            ea_bits_len=16,
            psid_offset=6,
            psid_length=4,
            mtu=1500,
            tag=tag,
        )

        # Enable MAP-T on interfaces.
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg0.sw_if_index, is_translation=1
        )
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg1.sw_if_index, is_translation=1
        )

        # Ensure MAP doesn't steal all packets!
        v4 = (
            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
            / IP(src=self.pg0.remote_ip4, dst=self.pg0.remote_ip4)
            / UDP(sport=20000, dport=10000)
            / Raw(b"\xa5" * 100)
        )
        rx = self.send_and_expect(self.pg0, v4 * 1, self.pg0)
        v4_reply = v4[1]
        v4_reply.ttl -= 1
        for p in rx:
            self.validate(p[1], v4_reply)
        # Ensure MAP doesn't steal all packets
        v6 = (
            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
            / IPv6(src=self.pg1.remote_ip6, dst=self.pg1.remote_ip6)
            / UDP(sport=20000, dport=10000)
            / Raw(b"\xa5" * 100)
        )
        rx = self.send_and_expect(self.pg1, v6 * 1, self.pg1)
        v6_reply = v6[1]
        v6_reply.hlim -= 1
        for p in rx:
            self.validate(p[1], v6_reply)

        map_route = VppIpRoute(
            self,
            "2001:db8::",
            32,
            [
                VppRoutePath(
                    self.pg1.remote_ip6,
                    self.pg1.sw_if_index,
                    proto=DpoProto.DPO_PROTO_IP6,
                )
            ],
        )
        map_route.add_vpp_config()

        #
        # Send a v4 packet that will be translated
        #
        p_ether = Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
        p_ip4 = IP(src=self.pg0.remote_ip4, dst="192.168.0.1")
        payload = TCP(sport=0xABCD, dport=0xABCD)

        p4 = p_ether / p_ip4 / payload
        p6_translated = (
            IPv6(src="1234:5678:90ab:cdef:ac:1001:200:0", dst="2001:db8:1f0::c0a8:1:f")
            / payload
        )
        p6_translated.hlim -= 1
        rx = self.send_and_expect(self.pg0, p4 * 1, self.pg1)
        for p in rx:
            self.validate(p[1], p6_translated)

        # Send back an IPv6 packet that will be "untranslated"
        p_ether6 = Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
        p_ip6 = IPv6(
            src="2001:db8:1f0::c0a8:1:f", dst="1234:5678:90ab:cdef:ac:1001:200:0"
        )
        p6 = p_ether6 / p_ip6 / payload
        p4_translated = IP(src="192.168.0.1", dst=self.pg0.remote_ip4) / payload
        p4_translated.id = 0
        p4_translated.ttl -= 1
        rx = self.send_and_expect(self.pg1, p6 * 1, self.pg0)
        for p in rx:
            self.validate(p[1], p4_translated)

        # IPv4 TTL=0
        ip4_ttl_expired = IP(src=self.pg0.remote_ip4, dst="192.168.0.1", ttl=0)
        p4 = p_ether / ip4_ttl_expired / payload

        icmp4_reply = (
            IP(id=0, ttl=254, src=self.pg0.local_ip4, dst=self.pg0.remote_ip4)
            / ICMP(type="time-exceeded", code="ttl-zero-during-transit")
            / IP(src=self.pg0.remote_ip4, dst="192.168.0.1", ttl=0)
            / payload
        )
        rx = self.send_and_expect(self.pg0, p4 * 1, self.pg0)
        for p in rx:
            self.validate(p[1], icmp4_reply)

        # IPv4 TTL=1
        ip4_ttl_expired = IP(src=self.pg0.remote_ip4, dst="192.168.0.1", ttl=1)
        p4 = p_ether / ip4_ttl_expired / payload

        icmp4_reply = (
            IP(id=0, ttl=254, src=self.pg0.local_ip4, dst=self.pg0.remote_ip4)
            / ICMP(type="time-exceeded", code="ttl-zero-during-transit")
            / IP(src=self.pg0.remote_ip4, dst="192.168.0.1", ttl=1)
            / payload
        )
        rx = self.send_and_expect(self.pg0, p4 * 1, self.pg0)
        for p in rx:
            self.validate(p[1], icmp4_reply)

        # IPv6 Hop limit at BR
        ip6_hlim_expired = IPv6(
            hlim=1,
            src="2001:db8:1ab::c0a8:1:ab",
            dst="1234:5678:90ab:cdef:ac:1001:200:0",
        )
        p6 = p_ether6 / ip6_hlim_expired / payload

        icmp6_reply = (
            IPv6(hlim=255, src=self.pg1.local_ip6, dst="2001:db8:1ab::c0a8:1:ab")
            / ICMPv6TimeExceeded(code=0)
            / IPv6(
                src="2001:db8:1ab::c0a8:1:ab",
                dst="1234:5678:90ab:cdef:ac:1001:200:0",
                hlim=1,
            )
            / payload
        )
        rx = self.send_and_expect(self.pg1, p6 * 1, self.pg1)
        for p in rx:
            self.validate(p[1], icmp6_reply)

        # IPv6 Hop limit beyond BR
        ip6_hlim_expired = IPv6(
            hlim=0,
            src="2001:db8:1ab::c0a8:1:ab",
            dst="1234:5678:90ab:cdef:ac:1001:200:0",
        )
        p6 = p_ether6 / ip6_hlim_expired / payload

        icmp6_reply = (
            IPv6(hlim=255, src=self.pg1.local_ip6, dst="2001:db8:1ab::c0a8:1:ab")
            / ICMPv6TimeExceeded(code=0)
            / IPv6(
                src="2001:db8:1ab::c0a8:1:ab",
                dst="1234:5678:90ab:cdef:ac:1001:200:0",
                hlim=0,
            )
            / payload
        )
        rx = self.send_and_expect(self.pg1, p6 * 1, self.pg1)
        for p in rx:
            self.validate(p[1], icmp6_reply)

        # IPv4 Well-known port
        p_ip4 = IP(src=self.pg0.remote_ip4, dst="192.168.0.1")
        payload = UDP(sport=200, dport=200)
        p4 = p_ether / p_ip4 / payload
        self.send_and_assert_no_replies(self.pg0, p4 * 1)

        # IPv6 Well-known port
        payload = UDP(sport=200, dport=200)
        p6 = p_ether6 / p_ip6 / payload
        self.send_and_assert_no_replies(self.pg1, p6 * 1)

        # UDP packet fragmentation
        payload_len = 1453
        payload = UDP(sport=40000, dport=4000) / self.payload(payload_len)
        p4 = p_ether / p_ip4 / payload
        self.pg_enable_capture()
        self.pg0.add_stream(p4)
        self.pg_start()
        rx = self.pg1.get_capture(2)

        p_ip6_translated = IPv6(
            src="1234:5678:90ab:cdef:ac:1001:200:0", dst="2001:db8:1e0::c0a8:1:e"
        )
        for p in rx:
            self.validate_frag6(p, p_ip6_translated)

        self.validate_frag_payload_len6(rx, UDP, payload_len)

        # UDP packet fragmentation send fragments
        payload_len = 1453
        payload = UDP(sport=40000, dport=4000) / self.payload(payload_len)
        p4 = p_ether / p_ip4 / payload
        frags = fragment_rfc791(p4, fragsize=1000)
        self.pg_enable_capture()
        self.pg0.add_stream(frags)
        self.pg_start()
        rx = self.pg1.get_capture(2)

        for p in rx:
            self.validate_frag6(p, p_ip6_translated)

        self.validate_frag_payload_len6(rx, UDP, payload_len)

        # Send back an fragmented IPv6 UDP packet that will be "untranslated"
        payload = UDP(sport=4000, dport=40000) / self.payload(payload_len)
        p_ether6 = Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
        p_ip6 = IPv6(
            src="2001:db8:1e0::c0a8:1:e", dst="1234:5678:90ab:cdef:ac:1001:200:0"
        )
        p6 = p_ether6 / p_ip6 / payload
        frags6 = fragment_rfc8200(p6, identification=0xDCBA, fragsize=1000)

        p_ip4_translated = IP(src="192.168.0.1", dst=self.pg0.remote_ip4)
        p4_translated = p_ip4_translated / payload
        p4_translated.id = 0
        p4_translated.ttl -= 1

        self.pg_enable_capture()
        self.pg1.add_stream(frags6)
        self.pg_start()
        rx = self.pg0.get_capture(2)

        for p in rx:
            self.validate_frag4(p, p4_translated)

        self.validate_frag_payload_len4(rx, UDP, payload_len)

        # ICMP packet fragmentation
        payload = ICMP(id=6529) / self.payload(payload_len)
        p4 = p_ether / p_ip4 / payload
        self.pg_enable_capture()
        self.pg0.add_stream(p4)
        self.pg_start()
        rx = self.pg1.get_capture(2)

        p_ip6_translated = IPv6(
            src="1234:5678:90ab:cdef:ac:1001:200:0", dst="2001:db8:160::c0a8:1:6"
        )
        for p in rx:
            self.validate_frag6(p, p_ip6_translated)

        self.validate_frag_payload_len6(rx, ICMPv6EchoRequest, payload_len)

        # ICMP packet fragmentation send fragments
        payload = ICMP(id=6529) / self.payload(payload_len)
        p4 = p_ether / p_ip4 / payload
        frags = fragment_rfc791(p4, fragsize=1000)
        self.pg_enable_capture()
        self.pg0.add_stream(frags)
        self.pg_start()
        rx = self.pg1.get_capture(2)

        for p in rx:
            self.validate_frag6(p, p_ip6_translated)

        self.validate_frag_payload_len6(rx, ICMPv6EchoRequest, payload_len)

        # TCP MSS clamping
        self.vapi.map_param_set_tcp(1300)

        #
        # Send a v4 TCP SYN packet that will be translated and MSS clamped
        #
        p_ether = Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
        p_ip4 = IP(src=self.pg0.remote_ip4, dst="192.168.0.1")
        payload = TCP(sport=0xABCD, dport=0xABCD, flags="S", options=[("MSS", 1460)])

        p4 = p_ether / p_ip4 / payload
        p6_translated = (
            IPv6(src="1234:5678:90ab:cdef:ac:1001:200:0", dst="2001:db8:1f0::c0a8:1:f")
            / payload
        )
        p6_translated.hlim -= 1
        p6_translated[TCP].options = [("MSS", 1300)]
        rx = self.send_and_expect(self.pg0, p4 * 1, self.pg1)
        for p in rx:
            self.validate(p[1], p6_translated)

        # Send back an IPv6 packet that will be "untranslated"
        p_ether6 = Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
        p_ip6 = IPv6(
            src="2001:db8:1f0::c0a8:1:f", dst="1234:5678:90ab:cdef:ac:1001:200:0"
        )
        p6 = p_ether6 / p_ip6 / payload
        p4_translated = IP(src="192.168.0.1", dst=self.pg0.remote_ip4) / payload
        p4_translated.id = 0
        p4_translated.ttl -= 1
        p4_translated[TCP].options = [("MSS", 1300)]
        rx = self.send_and_expect(self.pg1, p6 * 1, self.pg0)
        for p in rx:
            self.validate(p[1], p4_translated)

        # TCP MSS clamping cleanup
        self.vapi.map_param_set_tcp(0)

        # Enable icmp6 param to get back ICMPv6 unreachable messages in case
        # of security check fails
        self.vapi.map_param_set_icmp6(enable_unreachable=1)

        # Send back an IPv6 packet that will be droppped due to security
        # check fail
        p_ether6 = Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
        p_ip6_sec_check_fail = IPv6(
            src="2001:db8:1fe::c0a8:1:f", dst="1234:5678:90ab:cdef:ac:1001:200:0"
        )
        payload = TCP(sport=0xABCD, dport=0xABCD)
        p6 = p_ether6 / p_ip6_sec_check_fail / payload

        self.pg_send(self.pg1, p6 * 1)
        self.pg0.get_capture(0, timeout=1)
        rx = self.pg1.get_capture(1)

        icmp6_reply = (
            IPv6(hlim=255, src=self.pg1.local_ip6, dst="2001:db8:1fe::c0a8:1:f")
            / ICMPv6DestUnreach(code=5)
            / p_ip6_sec_check_fail
            / payload
        )

        for p in rx:
            self.validate(p[1], icmp6_reply)

        # ICMPv6 unreachable messages cleanup
        self.vapi.map_param_set_icmp6(enable_unreachable=0)

    def test_map_t_ip6_psid(self):
        """MAP-T v6->v4 PSID validation"""

        #
        # Add a domain that maps from pg0 to pg1
        #
        map_dst = "2001:db8::/32"
        map_src = "1234:5678:90ab:cdef::/64"
        ip4_pfx = "192.168.0.0/24"
        tag = "MAP-T Test Domain"

        self.vapi.map_add_domain(
            ip6_prefix=map_dst,
            ip4_prefix=ip4_pfx,
            ip6_src=map_src,
            ea_bits_len=16,
            psid_offset=6,
            psid_length=4,
            mtu=1500,
            tag=tag,
        )

        # Enable MAP-T on interfaces.
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg0.sw_if_index, is_translation=1
        )
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg1.sw_if_index, is_translation=1
        )

        map_route = VppIpRoute(
            self,
            "2001:db8::",
            32,
            [
                VppRoutePath(
                    self.pg1.remote_ip6,
                    self.pg1.sw_if_index,
                    proto=DpoProto.DPO_PROTO_IP6,
                )
            ],
        )
        map_route.add_vpp_config()

        p_ether6 = Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
        p_ip6 = IPv6(
            src="2001:db8:1f0::c0a8:1:f", dst="1234:5678:90ab:cdef:ac:1001:200:0"
        )

        # Send good IPv6 source port, ensure translated IPv4 received
        payload = TCP(sport=0xABCD, dport=80)
        p6 = p_ether6 / p_ip6 / payload
        p4_translated = IP(src="192.168.0.1", dst=self.pg0.remote_ip4) / payload
        p4_translated.id = 0
        p4_translated.ttl -= 1
        rx = self.send_and_expect(self.pg1, p6 * 1, self.pg0)
        for p in rx:
            self.validate(p[1], p4_translated)

        # Send bad IPv6 source port, ensure translated IPv4 not received
        payload = TCP(sport=0xDCBA, dport=80)
        p6 = p_ether6 / p_ip6 / payload
        self.send_and_assert_no_replies(self.pg1, p6 * 1)

    def test_map_t_pre_resolve(self):
        """MAP-T pre-resolve"""

        # Add a domain that maps from pg0 to pg1
        map_dst = "2001:db8::/32"
        map_src = "1234:5678:90ab:cdef::/64"
        ip4_pfx = "192.168.0.0/24"
        tag = "MAP-T Test Domain."

        self.vapi.map_add_domain(
            ip6_prefix=map_dst,
            ip4_prefix=ip4_pfx,
            ip6_src=map_src,
            ea_bits_len=16,
            psid_offset=6,
            psid_length=4,
            mtu=1500,
            tag=tag,
        )

        # Enable MAP-T on interfaces.
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg0.sw_if_index, is_translation=1
        )
        self.vapi.map_if_enable_disable(
            is_enable=1, sw_if_index=self.pg1.sw_if_index, is_translation=1
        )

        # Enable pre-resolve option
        self.vapi.map_param_add_del_pre_resolve(
            ip4_nh_address="10.1.2.3", ip6_nh_address="4001::1", is_add=1
        )

        # Add a route to 4001::1 and expect the translated traffic to be
        # sent via that route next-hop.
        pre_res_route6 = VppIpRoute(
            self,
            "4001::1",
            128,
            [VppRoutePath(self.pg1.remote_hosts[2].ip6, self.pg1.sw_if_index)],
        )
        pre_res_route6.add_vpp_config()

        # Add a route to 10.1.2.3 and expect the "untranslated" traffic to be
        # sent via that route next-hop.
        pre_res_route4 = VppIpRoute(
            self,
            "10.1.2.3",
            32,
            [VppRoutePath(self.pg0.remote_hosts[1].ip4, self.pg0.sw_if_index)],
        )
        pre_res_route4.add_vpp_config()

        # Send an IPv4 packet that will be translated
        p_ether = Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
        p_ip4 = IP(src=self.pg0.remote_ip4, dst="192.168.0.1")
        payload = TCP(sport=0xABCD, dport=0xABCD)
        p4 = p_ether / p_ip4 / payload

        p6_translated = (
            IPv6(src="1234:5678:90ab:cdef:ac:1001:200:0", dst="2001:db8:1f0::c0a8:1:f")
            / payload
        )
        p6_translated.hlim -= 1

        rx = self.send_and_expect(self.pg0, p4 * 1, self.pg1)
        for p in rx:
            self.assertEqual(p[Ether].dst, self.pg1.remote_hosts[2].mac)
            self.validate(p[1], p6_translated)

        # Send back an IPv6 packet that will be "untranslated"
        p_ether6 = Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
        p_ip6 = IPv6(
            src="2001:db8:1f0::c0a8:1:f", dst="1234:5678:90ab:cdef:ac:1001:200:0"
        )
        p6 = p_ether6 / p_ip6 / payload

        p4_translated = IP(src="192.168.0.1", dst=self.pg0.remote_ip4) / payload
        p4_translated.id = 0
        p4_translated.ttl -= 1

        rx = self.send_and_expect(self.pg1, p6 * 1, self.pg0)
        for p in rx:
            self.assertEqual(p[Ether].dst, self.pg0.remote_hosts[1].mac)
            self.validate(p[1], p4_translated)

        # Cleanup pre-resolve option
        self.vapi.map_param_add_del_pre_resolve(
            ip4_nh_address="10.1.2.3", ip6_nh_address="4001::1", is_add=0
        )


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