Translate matching packets using NAT (VPP-1069)
[vpp.git] / test / test_nat.py
index 37e1b1e..aeeb5aa 100644 (file)
@@ -3,15 +3,19 @@
 import socket
 import unittest
 import struct
+import StringIO
+import random
 
 from framework import VppTestCase, VppTestRunner, running_extended_tests
+from vpp_ip_route import VppIpRoute, VppRoutePath, DpoProto
 from scapy.layers.inet import IP, TCP, UDP, ICMP
 from scapy.layers.inet import IPerror, TCPerror, UDPerror, ICMPerror
 from scapy.layers.inet6 import IPv6, ICMPv6EchoRequest, ICMPv6EchoReply
-from scapy.layers.inet6 import ICMPv6DestUnreach, IPerror6
+from scapy.layers.inet6 import ICMPv6DestUnreach, IPerror6, IPv6ExtHdrFragment
 from scapy.layers.l2 import Ether, ARP, GRE
 from scapy.data import IP_PROTOS
-from scapy.packet import bind_layers
+from scapy.packet import bind_layers, Raw
+from scapy.all import fragment6
 from util import ppp
 from ipfix import IPFIX, Set, Template, Data, IPFIXDecoder
 from time import sleep
@@ -238,33 +242,44 @@ class MethodHolder(VppTestCase):
 
         return pkts
 
-    def create_stream_out(self, out_if, dst_ip=None, ttl=64):
+    def create_stream_out(self, out_if, dst_ip=None, ttl=64,
+                          use_inside_ports=False):
         """
         Create packet stream for outside network
 
         :param out_if: Outside interface
         :param dst_ip: Destination IP address (Default use global NAT address)
         :param ttl: TTL of generated packets
+        :param use_inside_ports: Use inside NAT ports as destination ports
+               instead of outside ports
         """
         if dst_ip is None:
             dst_ip = self.nat_addr
+        if not use_inside_ports:
+            tcp_port = self.tcp_port_out
+            udp_port = self.udp_port_out
+            icmp_id = self.icmp_id_out
+        else:
+            tcp_port = self.tcp_port_in
+            udp_port = self.udp_port_in
+            icmp_id = self.icmp_id_in
         pkts = []
         # TCP
         p = (Ether(dst=out_if.local_mac, src=out_if.remote_mac) /
              IP(src=out_if.remote_ip4, dst=dst_ip, ttl=ttl) /
-             TCP(dport=self.tcp_port_out, sport=20))
+             TCP(dport=tcp_port, sport=20))
         pkts.append(p)
 
         # UDP
         p = (Ether(dst=out_if.local_mac, src=out_if.remote_mac) /
              IP(src=out_if.remote_ip4, dst=dst_ip, ttl=ttl) /
-             UDP(dport=self.udp_port_out, sport=20))
+             UDP(dport=udp_port, sport=20))
         pkts.append(p)
 
         # ICMP
         p = (Ether(dst=out_if.local_mac, src=out_if.remote_mac) /
              IP(src=out_if.remote_ip4, dst=dst_ip, ttl=ttl) /
-             ICMP(id=self.icmp_id_out, type='echo-reply'))
+             ICMP(id=icmp_id, type='echo-reply'))
         pkts.append(p)
 
         return pkts
@@ -463,6 +478,121 @@ class MethodHolder(VppTestCase):
                                       "(inside network):", packet))
                 raise
 
+    def create_stream_frag(self, src_if, dst, sport, dport, data):
+        """
+        Create fragmented packet stream
+
+        :param src_if: Source interface
+        :param dst: Destination IPv4 address
+        :param sport: Source TCP port
+        :param dport: Destination TCP port
+        :param data: Payload data
+        :returns: Fragmets
+        """
+        id = random.randint(0, 65535)
+        p = (IP(src=src_if.remote_ip4, dst=dst) /
+             TCP(sport=sport, dport=dport) /
+             Raw(data))
+        p = p.__class__(str(p))
+        chksum = p['TCP'].chksum
+        pkts = []
+        p = (Ether(src=src_if.remote_mac, dst=src_if.local_mac) /
+             IP(src=src_if.remote_ip4, dst=dst, flags="MF", frag=0, id=id) /
+             TCP(sport=sport, dport=dport, chksum=chksum) /
+             Raw(data[0:4]))
+        pkts.append(p)
+        p = (Ether(src=src_if.remote_mac, dst=src_if.local_mac) /
+             IP(src=src_if.remote_ip4, dst=dst, flags="MF", frag=3, id=id,
+                proto=IP_PROTOS.tcp) /
+             Raw(data[4:20]))
+        pkts.append(p)
+        p = (Ether(src=src_if.remote_mac, dst=src_if.local_mac) /
+             IP(src=src_if.remote_ip4, dst=dst, frag=5, proto=IP_PROTOS.tcp,
+                id=id) /
+             Raw(data[20:]))
+        pkts.append(p)
+        return pkts
+
+    def create_stream_frag_ip6(self, src_if, dst, sport, dport, data,
+                               pref=None, plen=0, frag_size=128):
+        """
+        Create fragmented packet stream
+
+        :param src_if: Source interface
+        :param dst: Destination IPv4 address
+        :param sport: Source TCP port
+        :param dport: Destination TCP port
+        :param data: Payload data
+        :param pref: NAT64 prefix
+        :param plen: NAT64 prefix length
+        :param fragsize: size of fragments
+        :returns: Fragmets
+        """
+        if pref is None:
+            dst_ip6 = ''.join(['64:ff9b::', dst])
+        else:
+            dst_ip6 = self.compose_ip6(dst, pref, plen)
+
+        p = (Ether(dst=src_if.local_mac, src=src_if.remote_mac) /
+             IPv6(src=src_if.remote_ip6, dst=dst_ip6) /
+             IPv6ExtHdrFragment(id=random.randint(0, 65535)) /
+             TCP(sport=sport, dport=dport) /
+             Raw(data))
+
+        return fragment6(p, frag_size)
+
+    def reass_frags_and_verify(self, frags, src, dst):
+        """
+        Reassemble and verify fragmented packet
+
+        :param frags: Captured fragments
+        :param src: Source IPv4 address to verify
+        :param dst: Destination IPv4 address to verify
+
+        :returns: Reassembled IPv4 packet
+        """
+        buffer = StringIO.StringIO()
+        for p in frags:
+            self.assertEqual(p[IP].src, src)
+            self.assertEqual(p[IP].dst, dst)
+            self.check_ip_checksum(p)
+            buffer.seek(p[IP].frag * 8)
+            buffer.write(p[IP].payload)
+        ip = frags[0].getlayer(IP)
+        ip = IP(src=frags[0][IP].src, dst=frags[0][IP].dst,
+                proto=frags[0][IP].proto)
+        if ip.proto == IP_PROTOS.tcp:
+            p = (ip / TCP(buffer.getvalue()))
+            self.check_tcp_checksum(p)
+        elif ip.proto == IP_PROTOS.udp:
+            p = (ip / UDP(buffer.getvalue()))
+        return p
+
+    def reass_frags_and_verify_ip6(self, frags, src, dst):
+        """
+        Reassemble and verify fragmented packet
+
+        :param frags: Captured fragments
+        :param src: Source IPv6 address to verify
+        :param dst: Destination IPv6 address to verify
+
+        :returns: Reassembled IPv6 packet
+        """
+        buffer = StringIO.StringIO()
+        for p in frags:
+            self.assertEqual(p[IPv6].src, src)
+            self.assertEqual(p[IPv6].dst, dst)
+            buffer.seek(p[IPv6ExtHdrFragment].offset * 8)
+            buffer.write(p[IPv6ExtHdrFragment].payload)
+        ip = IPv6(src=frags[0][IPv6].src, dst=frags[0][IPv6].dst,
+                  nh=frags[0][IPv6ExtHdrFragment].nh)
+        if ip.nh == IP_PROTOS.tcp:
+            p = (ip / TCP(buffer.getvalue()))
+            self.check_tcp_checksum(p)
+        elif ip.nh == IP_PROTOS.udp:
+            p = (ip / UDP(buffer.getvalue()))
+        return p
+
     def verify_ipfix_nat44_ses(self, data):
         """
         Verify IPFIX NAT44 session create/delete event
@@ -535,6 +665,7 @@ class TestNAT44(MethodHolder):
             cls.icmp_id_in = 6305
             cls.icmp_id_out = 6305
             cls.nat_addr = '10.0.0.3'
+            cls.nat_addr_n = socket.inet_pton(socket.AF_INET, cls.nat_addr)
             cls.ipfix_src_port = 4739
             cls.ipfix_domain_id = 1
 
@@ -618,7 +749,9 @@ class TestNAT44(MethodHolder):
 
         interfaces = self.vapi.nat44_interface_addr_dump()
         for intf in interfaces:
-            self.vapi.nat44_add_interface_addr(intf.sw_if_index, is_add=0)
+            self.vapi.nat44_add_interface_addr(intf.sw_if_index,
+                                               twice_nat=intf.twice_nat,
+                                               is_add=0)
 
         self.vapi.nat_ipfix(enable=0, src_port=self.ipfix_src_port,
                             domain_id=self.ipfix_domain_id)
@@ -651,6 +784,7 @@ class TestNAT44(MethodHolder):
                 addr_only=sm.addr_only,
                 vrf_id=sm.vrf_id,
                 protocol=sm.protocol,
+                twice_nat=sm.twice_nat,
                 is_add=0)
 
         lb_static_mappings = self.vapi.nat44_lb_static_mapping_dump()
@@ -659,21 +793,37 @@ class TestNAT44(MethodHolder):
                 lb_sm.external_addr,
                 lb_sm.external_port,
                 lb_sm.protocol,
-                lb_sm.vrf_id,
+                vrf_id=lb_sm.vrf_id,
+                twice_nat=lb_sm.twice_nat,
                 is_add=0,
                 local_num=0,
                 locals=[])
 
+        identity_mappings = self.vapi.nat44_identity_mapping_dump()
+        for id_m in identity_mappings:
+            self.vapi.nat44_add_del_identity_mapping(
+                addr_only=id_m.addr_only,
+                ip=id_m.ip_address,
+                port=id_m.port,
+                sw_if_index=id_m.sw_if_index,
+                vrf_id=id_m.vrf_id,
+                protocol=id_m.protocol,
+                is_add=0)
+
         adresses = self.vapi.nat44_address_dump()
         for addr in adresses:
             self.vapi.nat44_add_del_address_range(addr.ip_address,
                                                   addr.ip_address,
+                                                  twice_nat=addr.twice_nat,
                                                   is_add=0)
 
+        self.vapi.nat_set_reass()
+        self.vapi.nat_set_reass(is_ip6=1)
+
     def nat44_add_static_mapping(self, local_ip, external_ip='0.0.0.0',
                                  local_port=0, external_port=0, vrf_id=0,
                                  is_add=1, external_sw_if_index=0xFFFFFFFF,
-                                 proto=0):
+                                 proto=0, twice_nat=0):
         """
         Add/delete NAT44 static mapping
 
@@ -685,6 +835,7 @@ class TestNAT44(MethodHolder):
         :param is_add: 1 if add, 0 if delete (Default add)
         :param external_sw_if_index: External interface instead of IP address
         :param proto: IP protocol (Mandatory if port specified)
+        :param twice_nat: 1 if translate external host address and port
         """
         addr_only = 1
         if local_port and external_port:
@@ -700,18 +851,21 @@ class TestNAT44(MethodHolder):
             addr_only,
             vrf_id,
             proto,
+            twice_nat,
             is_add)
 
-    def nat44_add_address(self, ip, is_add=1, vrf_id=0xFFFFFFFF):
+    def nat44_add_address(self, ip, is_add=1, vrf_id=0xFFFFFFFF, twice_nat=0):
         """
         Add/delete NAT44 address
 
         :param ip: IP address
         :param is_add: 1 if add, 0 if delete (Default add)
+        :param twice_nat: twice NAT address for extenal hosts
         """
         nat_addr = socket.inet_pton(socket.AF_INET, ip)
         self.vapi.nat44_add_del_address_range(nat_addr, nat_addr, is_add,
-                                              vrf_id=vrf_id)
+                                              vrf_id=vrf_id,
+                                              twice_nat=twice_nat)
 
     def test_dynamic(self):
         """ NAT44 dynamic translation test """
@@ -902,6 +1056,66 @@ class TestNAT44(MethodHolder):
         self.verify_capture_out(capture, same_port=True, packet_num=1)
         self.assert_equal(capture[0][IP].proto, IP_PROTOS.icmp)
 
+    def test_forwarding(self):
+        """ NAT44 forwarding test """
+
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+        self.vapi.nat44_forwarding_enable_disable(1)
+
+        real_ip = self.pg0.remote_ip4n
+        alias_ip = self.nat_addr_n
+        self.vapi.nat44_add_del_static_mapping(local_ip=real_ip,
+                                               external_ip=alias_ip)
+
+        try:
+            # in2out - static mapping match
+
+            pkts = self.create_stream_out(self.pg1)
+            self.pg1.add_stream(pkts)
+            self.pg_enable_capture(self.pg_interfaces)
+            self.pg_start()
+            capture = self.pg0.get_capture(len(pkts))
+            self.verify_capture_in(capture, self.pg0)
+
+            pkts = self.create_stream_in(self.pg0, self.pg1)
+            self.pg0.add_stream(pkts)
+            self.pg_enable_capture(self.pg_interfaces)
+            self.pg_start()
+            capture = self.pg1.get_capture(len(pkts))
+            self.verify_capture_out(capture, same_port=True)
+
+            # in2out - no static mapping match
+
+            host0 = self.pg0.remote_hosts[0]
+            self.pg0.remote_hosts[0] = self.pg0.remote_hosts[1]
+            try:
+                pkts = self.create_stream_out(self.pg1,
+                                              dst_ip=self.pg0.remote_ip4,
+                                              use_inside_ports=True)
+                self.pg1.add_stream(pkts)
+                self.pg_enable_capture(self.pg_interfaces)
+                self.pg_start()
+                capture = self.pg0.get_capture(len(pkts))
+                self.verify_capture_in(capture, self.pg0)
+
+                pkts = self.create_stream_in(self.pg0, self.pg1)
+                self.pg0.add_stream(pkts)
+                self.pg_enable_capture(self.pg_interfaces)
+                self.pg_start()
+                capture = self.pg1.get_capture(len(pkts))
+                self.verify_capture_out(capture, nat_ip=self.pg0.remote_ip4,
+                                        same_port=True)
+            finally:
+                self.pg0.remote_hosts[0] = host0
+
+        finally:
+            self.vapi.nat44_forwarding_enable_disable(0)
+            self.vapi.nat44_add_del_static_mapping(local_ip=real_ip,
+                                                   external_ip=alias_ip,
+                                                   is_add=0)
+
     def test_static_in(self):
         """ 1:1 NAT initialized from inside network """
 
@@ -1068,6 +1282,35 @@ class TestNAT44(MethodHolder):
         self.pg_start()
         self.pg3.assert_nothing_captured()
 
+    def test_identity_nat(self):
+        """ Identity NAT """
+
+        self.vapi.nat44_add_del_identity_mapping(ip=self.pg0.remote_ip4n)
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+
+        p = (Ether(src=self.pg1.remote_mac, dst=self.pg1.local_mac) /
+             IP(src=self.pg1.remote_ip4, dst=self.pg0.remote_ip4) /
+             TCP(sport=12345, dport=56789))
+        self.pg1.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg0.get_capture(1)
+        p = capture[0]
+        try:
+            ip = p[IP]
+            tcp = p[TCP]
+            self.assertEqual(ip.dst, self.pg0.remote_ip4)
+            self.assertEqual(ip.src, self.pg1.remote_ip4)
+            self.assertEqual(tcp.dport, 56789)
+            self.assertEqual(tcp.sport, 12345)
+            self.check_tcp_checksum(p)
+            self.check_ip_checksum(p)
+        except:
+            self.logger.error(ppp("Unexpected or invalid packet:", p))
+            raise
+
     def test_static_lb(self):
         """ NAT44 local service load balancing """
         external_addr_n = socket.inet_pton(socket.AF_INET, self.nat_addr)
@@ -1663,6 +1906,38 @@ class TestNAT44(MethodHolder):
         static_mappings = self.vapi.nat44_static_mapping_dump()
         self.assertEqual(0, len(static_mappings))
 
+    def test_interface_addr_identity_nat(self):
+        """ Identity NAT with addresses from interface """
+
+        port = 53053
+        self.vapi.nat44_add_interface_addr(self.pg7.sw_if_index)
+        self.vapi.nat44_add_del_identity_mapping(
+            sw_if_index=self.pg7.sw_if_index,
+            port=port,
+            protocol=IP_PROTOS.tcp,
+            addr_only=0)
+
+        # identity mappings with external interface
+        identity_mappings = self.vapi.nat44_identity_mapping_dump()
+        self.assertEqual(1, len(identity_mappings))
+        self.assertEqual(self.pg7.sw_if_index,
+                         identity_mappings[0].sw_if_index)
+
+        # configure interface address and check identity mappings
+        self.pg7.config_ip4()
+        identity_mappings = self.vapi.nat44_identity_mapping_dump()
+        self.assertEqual(1, len(identity_mappings))
+        self.assertEqual(identity_mappings[0].ip_address,
+                         self.pg7.local_ip4n)
+        self.assertEqual(0xFFFFFFFF, identity_mappings[0].sw_if_index)
+        self.assertEqual(port, identity_mappings[0].port)
+        self.assertEqual(IP_PROTOS.tcp, identity_mappings[0].protocol)
+
+        # remove interface address and check identity mappings
+        self.pg7.unconfig_ip4()
+        identity_mappings = self.vapi.nat44_identity_mapping_dump()
+        self.assertEqual(0, len(identity_mappings))
+
     def test_ipfix_nat44_sess(self):
         """ IPFIX logging NAT44 session created/delted """
         self.ipfix_domain_id = 10
@@ -1862,7 +2137,7 @@ class TestNAT44(MethodHolder):
         nat_ip2 = "10.0.0.11"
 
         self.nat44_add_address(nat_ip1)
-        self.nat44_add_address(nat_ip2)
+        self.nat44_add_address(nat_ip2, vrf_id=99)
         self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
         self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index)
         self.vapi.nat44_interface_add_del_feature(self.pg2.sw_if_index,
@@ -2479,10 +2754,354 @@ class TestNAT44(MethodHolder):
         sessions = self.vapi.nat44_user_session_dump(self.pg0.remote_ip4n, 0)
         self.assertEqual(nsessions - len(sessions), 2)
 
+    def test_set_get_reass(self):
+        """ NAT44 set/get virtual fragmentation reassembly """
+        reas_cfg1 = self.vapi.nat_get_reass()
+
+        self.vapi.nat_set_reass(timeout=reas_cfg1.ip4_timeout + 5,
+                                max_reass=reas_cfg1.ip4_max_reass * 2,
+                                max_frag=reas_cfg1.ip4_max_frag * 2)
+
+        reas_cfg2 = self.vapi.nat_get_reass()
+
+        self.assertEqual(reas_cfg1.ip4_timeout + 5, reas_cfg2.ip4_timeout)
+        self.assertEqual(reas_cfg1.ip4_max_reass * 2, reas_cfg2.ip4_max_reass)
+        self.assertEqual(reas_cfg1.ip4_max_frag * 2, reas_cfg2.ip4_max_frag)
+
+        self.vapi.nat_set_reass(drop_frag=1)
+        self.assertTrue(self.vapi.nat_get_reass().ip4_drop_frag)
+
+    def test_frag_in_order(self):
+        """ NAT44 translate fragments arriving in order """
+        self.nat44_add_address(self.nat_addr)
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+
+        data = "A" * 4 + "B" * 16 + "C" * 3
+        self.tcp_port_in = random.randint(1025, 65535)
+
+        reass = self.vapi.nat_reass_dump()
+        reass_n_start = len(reass)
+
+        # in2out
+        pkts = self.create_stream_frag(self.pg0,
+                                       self.pg1.remote_ip4,
+                                       self.tcp_port_in,
+                                       20,
+                                       data)
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg1.get_capture(len(pkts))
+        p = self.reass_frags_and_verify(frags,
+                                        self.nat_addr,
+                                        self.pg1.remote_ip4)
+        self.assertEqual(p[TCP].dport, 20)
+        self.assertNotEqual(p[TCP].sport, self.tcp_port_in)
+        self.tcp_port_out = p[TCP].sport
+        self.assertEqual(data, p[Raw].load)
+
+        # out2in
+        pkts = self.create_stream_frag(self.pg1,
+                                       self.nat_addr,
+                                       20,
+                                       self.tcp_port_out,
+                                       data)
+        self.pg1.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg0.get_capture(len(pkts))
+        p = self.reass_frags_and_verify(frags,
+                                        self.pg1.remote_ip4,
+                                        self.pg0.remote_ip4)
+        self.assertEqual(p[TCP].sport, 20)
+        self.assertEqual(p[TCP].dport, self.tcp_port_in)
+        self.assertEqual(data, p[Raw].load)
+
+        reass = self.vapi.nat_reass_dump()
+        reass_n_end = len(reass)
+
+        self.assertEqual(reass_n_end - reass_n_start, 2)
+
+    def test_reass_hairpinning(self):
+        """ NAT44 fragments hairpinning """
+        host = self.pg0.remote_hosts[0]
+        server = self.pg0.remote_hosts[1]
+        host_in_port = random.randint(1025, 65535)
+        host_out_port = 0
+        server_in_port = random.randint(1025, 65535)
+        server_out_port = random.randint(1025, 65535)
+        data = "A" * 4 + "B" * 16 + "C" * 3
+
+        self.nat44_add_address(self.nat_addr)
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+        # add static mapping for server
+        self.nat44_add_static_mapping(server.ip4, self.nat_addr,
+                                      server_in_port, server_out_port,
+                                      proto=IP_PROTOS.tcp)
+
+        # send packet from host to server
+        pkts = self.create_stream_frag(self.pg0,
+                                       self.nat_addr,
+                                       host_in_port,
+                                       server_out_port,
+                                       data)
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg0.get_capture(len(pkts))
+        p = self.reass_frags_and_verify(frags,
+                                        self.nat_addr,
+                                        server.ip4)
+        self.assertNotEqual(p[TCP].sport, host_in_port)
+        self.assertEqual(p[TCP].dport, server_in_port)
+        self.assertEqual(data, p[Raw].load)
+
+    def test_frag_out_of_order(self):
+        """ NAT44 translate fragments arriving out of order """
+        self.nat44_add_address(self.nat_addr)
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+
+        data = "A" * 4 + "B" * 16 + "C" * 3
+        random.randint(1025, 65535)
+
+        # in2out
+        pkts = self.create_stream_frag(self.pg0,
+                                       self.pg1.remote_ip4,
+                                       self.tcp_port_in,
+                                       20,
+                                       data)
+        pkts.reverse()
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg1.get_capture(len(pkts))
+        p = self.reass_frags_and_verify(frags,
+                                        self.nat_addr,
+                                        self.pg1.remote_ip4)
+        self.assertEqual(p[TCP].dport, 20)
+        self.assertNotEqual(p[TCP].sport, self.tcp_port_in)
+        self.tcp_port_out = p[TCP].sport
+        self.assertEqual(data, p[Raw].load)
+
+        # out2in
+        pkts = self.create_stream_frag(self.pg1,
+                                       self.nat_addr,
+                                       20,
+                                       self.tcp_port_out,
+                                       data)
+        pkts.reverse()
+        self.pg1.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg0.get_capture(len(pkts))
+        p = self.reass_frags_and_verify(frags,
+                                        self.pg1.remote_ip4,
+                                        self.pg0.remote_ip4)
+        self.assertEqual(p[TCP].sport, 20)
+        self.assertEqual(p[TCP].dport, self.tcp_port_in)
+        self.assertEqual(data, p[Raw].load)
+
+    def test_port_restricted(self):
+        """ Port restricted NAT44 (MAP-E CE) """
+        self.nat44_add_address(self.nat_addr)
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+        self.vapi.cli("nat addr-port-assignment-alg map-e psid 10 "
+                      "psid-offset 6 psid-len 6")
+
+        p = (Ether(src=self.pg0.remote_mac, dst=self.pg0.local_mac) /
+             IP(src=self.pg0.remote_ip4, dst=self.pg1.remote_ip4) /
+             TCP(sport=4567, dport=22))
+        self.pg0.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg1.get_capture(1)
+        p = capture[0]
+        try:
+            ip = p[IP]
+            tcp = p[TCP]
+            self.assertEqual(ip.dst, self.pg1.remote_ip4)
+            self.assertEqual(ip.src, self.nat_addr)
+            self.assertEqual(tcp.dport, 22)
+            self.assertNotEqual(tcp.sport, 4567)
+            self.assertEqual((tcp.sport >> 6) & 63, 10)
+            self.check_tcp_checksum(p)
+            self.check_ip_checksum(p)
+        except:
+            self.logger.error(ppp("Unexpected or invalid packet:", p))
+            raise
+
+    def test_twice_nat(self):
+        """ Twice NAT44 """
+        twice_nat_addr = '10.0.1.3'
+        port_in = 8080
+        port_out = 80
+        eh_port_out = 4567
+        eh_port_in = 0
+        self.nat44_add_address(self.nat_addr)
+        self.nat44_add_address(twice_nat_addr, twice_nat=1)
+        self.nat44_add_static_mapping(self.pg0.remote_ip4, self.nat_addr,
+                                      port_in, port_out, proto=IP_PROTOS.tcp,
+                                      twice_nat=1)
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+
+        p = (Ether(src=self.pg1.remote_mac, dst=self.pg1.local_mac) /
+             IP(src=self.pg1.remote_ip4, dst=self.nat_addr) /
+             TCP(sport=eh_port_out, dport=port_out))
+        self.pg1.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg0.get_capture(1)
+        p = capture[0]
+        try:
+            ip = p[IP]
+            tcp = p[TCP]
+            self.assertEqual(ip.dst, self.pg0.remote_ip4)
+            self.assertEqual(ip.src, twice_nat_addr)
+            self.assertEqual(tcp.dport, port_in)
+            self.assertNotEqual(tcp.sport, eh_port_out)
+            eh_port_in = tcp.sport
+            self.check_tcp_checksum(p)
+            self.check_ip_checksum(p)
+        except:
+            self.logger.error(ppp("Unexpected or invalid packet:", p))
+            raise
+
+        p = (Ether(src=self.pg0.remote_mac, dst=self.pg0.local_mac) /
+             IP(src=self.pg0.remote_ip4, dst=twice_nat_addr) /
+             TCP(sport=port_in, dport=eh_port_in))
+        self.pg0.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg1.get_capture(1)
+        p = capture[0]
+        try:
+            ip = p[IP]
+            tcp = p[TCP]
+            self.assertEqual(ip.dst, self.pg1.remote_ip4)
+            self.assertEqual(ip.src, self.nat_addr)
+            self.assertEqual(tcp.dport, eh_port_out)
+            self.assertEqual(tcp.sport, port_out)
+            self.check_tcp_checksum(p)
+            self.check_ip_checksum(p)
+        except:
+            self.logger.error(ppp("Unexpected or invalid packet:", p))
+            raise
+
+    def test_twice_nat_lb(self):
+        """ Twice NAT44 local service load balancing """
+        external_addr_n = socket.inet_pton(socket.AF_INET, self.nat_addr)
+        twice_nat_addr = '10.0.1.3'
+        local_port = 8080
+        external_port = 80
+        eh_port_out = 4567
+        eh_port_in = 0
+        server1 = self.pg0.remote_hosts[0]
+        server2 = self.pg0.remote_hosts[1]
+
+        locals = [{'addr': server1.ip4n,
+                   'port': local_port,
+                   'probability': 50},
+                  {'addr': server2.ip4n,
+                   'port': local_port,
+                   'probability': 50}]
+
+        self.nat44_add_address(self.nat_addr)
+        self.nat44_add_address(twice_nat_addr, twice_nat=1)
+
+        self.vapi.nat44_add_del_lb_static_mapping(external_addr_n,
+                                                  external_port,
+                                                  IP_PROTOS.tcp,
+                                                  twice_nat=1,
+                                                  local_num=len(locals),
+                                                  locals=locals)
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+
+        p = (Ether(src=self.pg1.remote_mac, dst=self.pg1.local_mac) /
+             IP(src=self.pg1.remote_ip4, dst=self.nat_addr) /
+             TCP(sport=eh_port_out, dport=external_port))
+        self.pg1.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg0.get_capture(1)
+        p = capture[0]
+        server = None
+        try:
+            ip = p[IP]
+            tcp = p[TCP]
+            self.assertEqual(ip.src, twice_nat_addr)
+            self.assertIn(ip.dst, [server1.ip4, server2.ip4])
+            if ip.dst == server1.ip4:
+                server = server1
+            else:
+                server = server2
+            self.assertNotEqual(tcp.sport, eh_port_out)
+            eh_port_in = tcp.sport
+            self.assertEqual(tcp.dport, local_port)
+            self.check_tcp_checksum(p)
+            self.check_ip_checksum(p)
+        except:
+            self.logger.error(ppp("Unexpected or invalid packet:", p))
+            raise
+
+        p = (Ether(src=server.mac, dst=self.pg0.local_mac) /
+             IP(src=server.ip4, dst=twice_nat_addr) /
+             TCP(sport=local_port, dport=eh_port_in))
+        self.pg0.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg1.get_capture(1)
+        p = capture[0]
+        try:
+            ip = p[IP]
+            tcp = p[TCP]
+            self.assertEqual(ip.src, self.nat_addr)
+            self.assertEqual(ip.dst, self.pg1.remote_ip4)
+            self.assertEqual(tcp.sport, external_port)
+            self.assertEqual(tcp.dport, eh_port_out)
+            self.check_tcp_checksum(p)
+            self.check_ip_checksum(p)
+        except:
+            self.logger.error(ppp("Unexpected or invalid packet:", p))
+            raise
+
+    def test_twice_nat_interface_addr(self):
+        """ Acquire twice NAT44 addresses from interface """
+        self.vapi.nat44_add_interface_addr(self.pg7.sw_if_index, twice_nat=1)
+
+        # no address in NAT pool
+        adresses = self.vapi.nat44_address_dump()
+        self.assertEqual(0, len(adresses))
+
+        # configure interface address and check NAT address pool
+        self.pg7.config_ip4()
+        adresses = self.vapi.nat44_address_dump()
+        self.assertEqual(1, len(adresses))
+        self.assertEqual(adresses[0].ip_address[0:4], self.pg7.local_ip4n)
+        self.assertEqual(adresses[0].twice_nat, 1)
+
+        # remove interface address and check NAT address pool
+        self.pg7.unconfig_ip4()
+        adresses = self.vapi.nat44_address_dump()
+        self.assertEqual(0, len(adresses))
+
     def tearDown(self):
         super(TestNAT44, self).tearDown()
         if not self.vpp_dead:
             self.logger.info(self.vapi.cli("show nat44 verbose"))
+            self.logger.info(self.vapi.cli("show nat virtual-reassembly"))
+            self.vapi.cli("nat addr-port-assignment-alg default")
             self.clear_nat44()
 
 
@@ -3150,7 +3769,7 @@ class TestNAT64(MethodHolder):
             cls.vrf1_nat_addr_n = socket.inet_pton(socket.AF_INET,
                                                    cls.vrf1_nat_addr)
 
-            cls.create_pg_interfaces(range(4))
+            cls.create_pg_interfaces(range(5))
             cls.ip6_interfaces = list(cls.pg_interfaces[0:1])
             cls.ip6_interfaces.append(cls.pg_interfaces[2])
             cls.ip4_interfaces = list(cls.pg_interfaces[1:2])
@@ -3927,6 +4546,157 @@ class TestNAT64(MethodHolder):
             self.logger.error(ppp("Unexpected or invalid packet:", p))
             raise
 
+    def test_frag_in_order(self):
+        """ NAT64 translate fragments arriving in order """
+        self.tcp_port_in = random.randint(1025, 65535)
+
+        self.vapi.nat64_add_del_pool_addr_range(self.nat_addr_n,
+                                                self.nat_addr_n)
+        self.vapi.nat64_add_del_interface(self.pg0.sw_if_index)
+        self.vapi.nat64_add_del_interface(self.pg1.sw_if_index, is_inside=0)
+
+        reass = self.vapi.nat_reass_dump()
+        reass_n_start = len(reass)
+
+        # in2out
+        data = 'a' * 200
+        pkts = self.create_stream_frag_ip6(self.pg0, self.pg1.remote_ip4,
+                                           self.tcp_port_in, 20, data)
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg1.get_capture(len(pkts))
+        p = self.reass_frags_and_verify(frags,
+                                        self.nat_addr,
+                                        self.pg1.remote_ip4)
+        self.assertEqual(p[TCP].dport, 20)
+        self.assertNotEqual(p[TCP].sport, self.tcp_port_in)
+        self.tcp_port_out = p[TCP].sport
+        self.assertEqual(data, p[Raw].load)
+
+        # out2in
+        data = "A" * 4 + "b" * 16 + "C" * 3
+        pkts = self.create_stream_frag(self.pg1,
+                                       self.nat_addr,
+                                       20,
+                                       self.tcp_port_out,
+                                       data)
+        self.pg1.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg0.get_capture(len(pkts))
+        src = self.compose_ip6(self.pg1.remote_ip4, '64:ff9b::', 96)
+        p = self.reass_frags_and_verify_ip6(frags, src, self.pg0.remote_ip6)
+        self.assertEqual(p[TCP].sport, 20)
+        self.assertEqual(p[TCP].dport, self.tcp_port_in)
+        self.assertEqual(data, p[Raw].load)
+
+        reass = self.vapi.nat_reass_dump()
+        reass_n_end = len(reass)
+
+        self.assertEqual(reass_n_end - reass_n_start, 2)
+
+    def test_reass_hairpinning(self):
+        """ NAT64 fragments hairpinning """
+        data = 'a' * 200
+        client = self.pg0.remote_hosts[0]
+        server = self.pg0.remote_hosts[1]
+        server_in_port = random.randint(1025, 65535)
+        server_out_port = random.randint(1025, 65535)
+        client_in_port = random.randint(1025, 65535)
+        ip = IPv6(src=''.join(['64:ff9b::', self.nat_addr]))
+        nat_addr_ip6 = ip.src
+
+        self.vapi.nat64_add_del_pool_addr_range(self.nat_addr_n,
+                                                self.nat_addr_n)
+        self.vapi.nat64_add_del_interface(self.pg0.sw_if_index)
+        self.vapi.nat64_add_del_interface(self.pg1.sw_if_index, is_inside=0)
+
+        # add static BIB entry for server
+        self.vapi.nat64_add_del_static_bib(server.ip6n,
+                                           self.nat_addr_n,
+                                           server_in_port,
+                                           server_out_port,
+                                           IP_PROTOS.tcp)
+
+        # send packet from host to server
+        pkts = self.create_stream_frag_ip6(self.pg0,
+                                           self.nat_addr,
+                                           client_in_port,
+                                           server_out_port,
+                                           data)
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg0.get_capture(len(pkts))
+        p = self.reass_frags_and_verify_ip6(frags, nat_addr_ip6, server.ip6)
+        self.assertNotEqual(p[TCP].sport, client_in_port)
+        self.assertEqual(p[TCP].dport, server_in_port)
+        self.assertEqual(data, p[Raw].load)
+
+    def test_frag_out_of_order(self):
+        """ NAT64 translate fragments arriving out of order """
+        self.tcp_port_in = random.randint(1025, 65535)
+
+        self.vapi.nat64_add_del_pool_addr_range(self.nat_addr_n,
+                                                self.nat_addr_n)
+        self.vapi.nat64_add_del_interface(self.pg0.sw_if_index)
+        self.vapi.nat64_add_del_interface(self.pg1.sw_if_index, is_inside=0)
+
+        # in2out
+        data = 'a' * 200
+        pkts = self.create_stream_frag_ip6(self.pg0, self.pg1.remote_ip4,
+                                           self.tcp_port_in, 20, data)
+        pkts.reverse()
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg1.get_capture(len(pkts))
+        p = self.reass_frags_and_verify(frags,
+                                        self.nat_addr,
+                                        self.pg1.remote_ip4)
+        self.assertEqual(p[TCP].dport, 20)
+        self.assertNotEqual(p[TCP].sport, self.tcp_port_in)
+        self.tcp_port_out = p[TCP].sport
+        self.assertEqual(data, p[Raw].load)
+
+        # out2in
+        data = "A" * 4 + "B" * 16 + "C" * 3
+        pkts = self.create_stream_frag(self.pg1,
+                                       self.nat_addr,
+                                       20,
+                                       self.tcp_port_out,
+                                       data)
+        pkts.reverse()
+        self.pg1.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        frags = self.pg0.get_capture(len(pkts))
+        src = self.compose_ip6(self.pg1.remote_ip4, '64:ff9b::', 96)
+        p = self.reass_frags_and_verify_ip6(frags, src, self.pg0.remote_ip6)
+        self.assertEqual(p[TCP].sport, 20)
+        self.assertEqual(p[TCP].dport, self.tcp_port_in)
+        self.assertEqual(data, p[Raw].load)
+
+    def test_interface_addr(self):
+        """ Acquire NAT64 pool addresses from interface """
+        self.vapi.nat64_add_interface_addr(self.pg4.sw_if_index)
+
+        # no address in NAT64 pool
+        adresses = self.vapi.nat44_address_dump()
+        self.assertEqual(0, len(adresses))
+
+        # configure interface address and check NAT64 address pool
+        self.pg4.config_ip4()
+        addresses = self.vapi.nat64_pool_addr_dump()
+        self.assertEqual(len(addresses), 1)
+        self.assertEqual(addresses[0].address, self.pg4.local_ip4n)
+
+        # remove interface address and check NAT64 address pool
+        self.pg4.unconfig_ip4()
+        addresses = self.vapi.nat64_pool_addr_dump()
+        self.assertEqual(0, len(adresses))
+
     def nat64_get_ses_num(self):
         """
         Return number of active NAT64 sessions.
@@ -4005,7 +4775,169 @@ class TestNAT64(MethodHolder):
             self.logger.info(self.vapi.cli("show nat64 prefix"))
             self.logger.info(self.vapi.cli("show nat64 bib all"))
             self.logger.info(self.vapi.cli("show nat64 session table all"))
+            self.logger.info(self.vapi.cli("show nat virtual-reassembly"))
             self.clear_nat64()
 
+
+class TestDSlite(MethodHolder):
+    """ DS-Lite Test Cases """
+
+    @classmethod
+    def setUpClass(cls):
+        super(TestDSlite, cls).setUpClass()
+
+        try:
+            cls.nat_addr = '10.0.0.3'
+            cls.nat_addr_n = socket.inet_pton(socket.AF_INET, cls.nat_addr)
+
+            cls.create_pg_interfaces(range(2))
+            cls.pg0.admin_up()
+            cls.pg0.config_ip4()
+            cls.pg0.resolve_arp()
+            cls.pg1.admin_up()
+            cls.pg1.config_ip6()
+            cls.pg1.generate_remote_hosts(2)
+            cls.pg1.configure_ipv6_neighbors()
+
+        except Exception:
+            super(TestDSlite, cls).tearDownClass()
+            raise
+
+    def test_dslite(self):
+        """ Test DS-Lite """
+        self.vapi.dslite_add_del_pool_addr_range(self.nat_addr_n,
+                                                 self.nat_addr_n)
+        aftr_ip4 = '192.0.0.1'
+        aftr_ip4_n = socket.inet_pton(socket.AF_INET, aftr_ip4)
+        aftr_ip6 = '2001:db8:85a3::8a2e:370:1'
+        aftr_ip6_n = socket.inet_pton(socket.AF_INET6, aftr_ip6)
+        self.vapi.dslite_set_aftr_addr(aftr_ip6_n, aftr_ip4_n)
+
+        # UDP
+        p = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
+             IPv6(dst=aftr_ip6, src=self.pg1.remote_hosts[0].ip6) /
+             IP(dst=self.pg0.remote_ip4, src='192.168.1.1') /
+             UDP(sport=20000, dport=10000))
+        self.pg1.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg0.get_capture(1)
+        capture = capture[0]
+        self.assertFalse(capture.haslayer(IPv6))
+        self.assertEqual(capture[IP].src, self.nat_addr)
+        self.assertEqual(capture[IP].dst, self.pg0.remote_ip4)
+        self.assertNotEqual(capture[UDP].sport, 20000)
+        self.assertEqual(capture[UDP].dport, 10000)
+        self.check_ip_checksum(capture)
+        out_port = capture[UDP].sport
+
+        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
+             IP(dst=self.nat_addr, src=self.pg0.remote_ip4) /
+             UDP(sport=10000, dport=out_port))
+        self.pg0.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg1.get_capture(1)
+        capture = capture[0]
+        self.assertEqual(capture[IPv6].src, aftr_ip6)
+        self.assertEqual(capture[IPv6].dst, self.pg1.remote_hosts[0].ip6)
+        self.assertEqual(capture[IP].src, self.pg0.remote_ip4)
+        self.assertEqual(capture[IP].dst, '192.168.1.1')
+        self.assertEqual(capture[UDP].sport, 10000)
+        self.assertEqual(capture[UDP].dport, 20000)
+        self.check_ip_checksum(capture)
+
+        # TCP
+        p = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
+             IPv6(dst=aftr_ip6, src=self.pg1.remote_hosts[1].ip6) /
+             IP(dst=self.pg0.remote_ip4, src='192.168.1.1') /
+             TCP(sport=20001, dport=10001))
+        self.pg1.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg0.get_capture(1)
+        capture = capture[0]
+        self.assertFalse(capture.haslayer(IPv6))
+        self.assertEqual(capture[IP].src, self.nat_addr)
+        self.assertEqual(capture[IP].dst, self.pg0.remote_ip4)
+        self.assertNotEqual(capture[TCP].sport, 20001)
+        self.assertEqual(capture[TCP].dport, 10001)
+        self.check_ip_checksum(capture)
+        self.check_tcp_checksum(capture)
+        out_port = capture[TCP].sport
+
+        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
+             IP(dst=self.nat_addr, src=self.pg0.remote_ip4) /
+             TCP(sport=10001, dport=out_port))
+        self.pg0.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg1.get_capture(1)
+        capture = capture[0]
+        self.assertEqual(capture[IPv6].src, aftr_ip6)
+        self.assertEqual(capture[IPv6].dst, self.pg1.remote_hosts[1].ip6)
+        self.assertEqual(capture[IP].src, self.pg0.remote_ip4)
+        self.assertEqual(capture[IP].dst, '192.168.1.1')
+        self.assertEqual(capture[TCP].sport, 10001)
+        self.assertEqual(capture[TCP].dport, 20001)
+        self.check_ip_checksum(capture)
+        self.check_tcp_checksum(capture)
+
+        # ICMP
+        p = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
+             IPv6(dst=aftr_ip6, src=self.pg1.remote_hosts[1].ip6) /
+             IP(dst=self.pg0.remote_ip4, src='192.168.1.1') /
+             ICMP(id=4000, type='echo-request'))
+        self.pg1.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg0.get_capture(1)
+        capture = capture[0]
+        self.assertFalse(capture.haslayer(IPv6))
+        self.assertEqual(capture[IP].src, self.nat_addr)
+        self.assertEqual(capture[IP].dst, self.pg0.remote_ip4)
+        self.assertNotEqual(capture[ICMP].id, 4000)
+        self.check_ip_checksum(capture)
+        self.check_icmp_checksum(capture)
+        out_id = capture[ICMP].id
+
+        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
+             IP(dst=self.nat_addr, src=self.pg0.remote_ip4) /
+             ICMP(id=out_id, type='echo-reply'))
+        self.pg0.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg1.get_capture(1)
+        capture = capture[0]
+        self.assertEqual(capture[IPv6].src, aftr_ip6)
+        self.assertEqual(capture[IPv6].dst, self.pg1.remote_hosts[1].ip6)
+        self.assertEqual(capture[IP].src, self.pg0.remote_ip4)
+        self.assertEqual(capture[IP].dst, '192.168.1.1')
+        self.assertEqual(capture[ICMP].id, 4000)
+        self.check_ip_checksum(capture)
+        self.check_icmp_checksum(capture)
+
+        # ping DS-Lite AFTR tunnel endpoint address
+        p = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
+             IPv6(src=self.pg1.remote_hosts[1].ip6, dst=aftr_ip6) /
+             ICMPv6EchoRequest())
+        self.pg1.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg1.get_capture(1)
+        self.assertEqual(1, len(capture))
+        capture = capture[0]
+        self.assertEqual(capture[IPv6].src, aftr_ip6)
+        self.assertEqual(capture[IPv6].dst, self.pg1.remote_hosts[1].ip6)
+        self.assertTrue(capture.haslayer(ICMPv6EchoReply))
+
+    def tearDown(self):
+        super(TestDSlite, self).tearDown()
+        if not self.vpp_dead:
+            self.logger.info(self.vapi.cli("show dslite pool"))
+            self.logger.info(
+                self.vapi.cli("show dslite aftr-tunnel-endpoint-address"))
+            self.logger.info(self.vapi.cli("show dslite sessions"))
+
 if __name__ == '__main__':
     unittest.main(testRunner=VppTestRunner)