X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=test%2Ftest_ip4.py;h=ddfd21874901fe7aa1caa36ec78747b1f9dc32f3;hb=71275e3d1ed4b7a536b7ec8d13995743beccde6b;hp=d219ec9f98143617ad9227e3e1d7633f5f2ea769;hpb=7bb873a4cc068a6cc3c9d0e1d32987c5f8003904;p=vpp.git

diff --git a/test/test_ip4.py b/test/test_ip4.py
index d219ec9f981..ddfd2187490 100644
--- a/test/test_ip4.py
+++ b/test/test_ip4.py
@@ -1,15 +1,18 @@
 #!/usr/bin/env python
-
-import unittest
+import random
 import socket
+import unittest
 
 from framework import VppTestCase, VppTestRunner
 from vpp_sub_interface import VppSubInterface, VppDot1QSubint, VppDot1ADSubint
+from vpp_ip_route import VppIpRoute, VppRoutePath, VppIpMRoute, \
+    VppMRoutePath, MRouteItfFlags, MRouteEntryFlags, VppMplsIpBind
 
 from scapy.packet import Raw
-from scapy.layers.l2 import Ether, Dot1Q
-from scapy.layers.inet import IP, UDP
+from scapy.layers.l2 import Ether, Dot1Q, ARP
+from scapy.layers.inet import IP, UDP, ICMP, icmptypes, icmpcodes
 from util import ppp
+from scapy.contrib.mpls import MPLS
 
 
 class TestIPv4(VppTestCase):
@@ -108,8 +111,7 @@ class TestIPv4(VppTestCase):
         pkts = []
         for i in range(0, 257):
             dst_if = self.flows[src_if][i % 2]
-            info = self.create_packet_info(
-                src_if.sw_if_index, dst_if.sw_if_index)
+            info = self.create_packet_info(src_if, dst_if)
             payload = self.info_to_payload(info)
             p = (Ether(dst=src_if.local_mac, src=src_if.remote_mac) /
                  IP(src=src_if.remote_ip4, dst=dst_if.remote_ip4) /
@@ -149,8 +151,9 @@ class TestIPv4(VppTestCase):
                 payload_info = self.payload_to_info(str(packet[Raw]))
                 packet_index = payload_info.index
                 self.assertEqual(payload_info.dst, dst_sw_if_index)
-                self.logger.debug("Got packet on port %s: src=%u (id=%u)" %
-                                  (dst_if.name, payload_info.src, packet_index))
+                self.logger.debug(
+                    "Got packet on port %s: src=%u (id=%u)" %
+                    (dst_if.name, payload_info.src, packet_index))
                 next_info = self.get_next_packet_info_for_interface2(
                     payload_info.src, dst_sw_if_index,
                     last_info[payload_info.src])
@@ -201,5 +204,729 @@ class TestIPv4(VppTestCase):
             self.verify_capture(i, pkts)
 
 
+class TestIPv4FibCrud(VppTestCase):
+    """ FIB - add/update/delete - ip4 routes
+
+    Test scenario:
+        - add 1k,
+        - del 100,
+        - add new 1k,
+        - del 1.5k
+
+    ..note:: Python API is too slow to add many routes, needs replacement.
+    """
+
+    def config_fib_many_to_one(self, start_dest_addr, next_hop_addr, count):
+        """
+
+        :param start_dest_addr:
+        :param next_hop_addr:
+        :param count:
+        :return list: added ips with 32 prefix
+        """
+        added_ips = []
+        dest_addr = int(socket.inet_pton(socket.AF_INET,
+                                         start_dest_addr).encode('hex'),
+                        16)
+        dest_addr_len = 32
+        n_next_hop_addr = socket.inet_pton(socket.AF_INET, next_hop_addr)
+        for _ in range(count):
+            n_dest_addr = '{:08x}'.format(dest_addr).decode('hex')
+            self.vapi.ip_add_del_route(n_dest_addr, dest_addr_len,
+                                       n_next_hop_addr)
+            added_ips.append(socket.inet_ntoa(n_dest_addr))
+            dest_addr += 1
+        return added_ips
+
+    def unconfig_fib_many_to_one(self, start_dest_addr, next_hop_addr, count):
+
+        removed_ips = []
+        dest_addr = int(socket.inet_pton(socket.AF_INET,
+                                         start_dest_addr).encode('hex'),
+                        16)
+        dest_addr_len = 32
+        n_next_hop_addr = socket.inet_pton(socket.AF_INET, next_hop_addr)
+        for _ in range(count):
+            n_dest_addr = '{:08x}'.format(dest_addr).decode('hex')
+            self.vapi.ip_add_del_route(n_dest_addr, dest_addr_len,
+                                       n_next_hop_addr, is_add=0)
+            removed_ips.append(socket.inet_ntoa(n_dest_addr))
+            dest_addr += 1
+        return removed_ips
+
+    def create_stream(self, src_if, dst_if, dst_ips, count):
+        pkts = []
+
+        for _ in range(count):
+            dst_addr = random.choice(dst_ips)
+            info = self.create_packet_info(src_if, dst_if)
+            payload = self.info_to_payload(info)
+            p = (Ether(dst=src_if.local_mac, src=src_if.remote_mac) /
+                 IP(src=src_if.remote_ip4, dst=dst_addr) /
+                 UDP(sport=1234, dport=1234) /
+                 Raw(payload))
+            info.data = p.copy()
+            self.extend_packet(p, random.choice(self.pg_if_packet_sizes))
+            pkts.append(p)
+
+        return pkts
+
+    def _find_ip_match(self, find_in, pkt):
+        for p in find_in:
+            if self.payload_to_info(str(p[Raw])) == \
+                    self.payload_to_info(str(pkt[Raw])):
+                if p[IP].src != pkt[IP].src:
+                    break
+                if p[IP].dst != pkt[IP].dst:
+                    break
+                if p[UDP].sport != pkt[UDP].sport:
+                    break
+                if p[UDP].dport != pkt[UDP].dport:
+                    break
+                return p
+        return None
+
+    @staticmethod
+    def _match_route_detail(route_detail, ip, address_length=32, table_id=0):
+        if route_detail.address == socket.inet_pton(socket.AF_INET, ip):
+            if route_detail.table_id != table_id:
+                return False
+            elif route_detail.address_length != address_length:
+                return False
+            else:
+                return True
+        else:
+            return False
+
+    def verify_capture(self, dst_interface, received_pkts, expected_pkts):
+        self.assertEqual(len(received_pkts), len(expected_pkts))
+        to_verify = list(expected_pkts)
+        for p in received_pkts:
+            self.assertEqual(p.src, dst_interface.local_mac)
+            self.assertEqual(p.dst, dst_interface.remote_mac)
+            x = self._find_ip_match(to_verify, p)
+            to_verify.remove(x)
+        self.assertListEqual(to_verify, [])
+
+    def verify_route_dump(self, fib_dump, ips):
+
+        def _ip_in_route_dump(ip, fib_dump):
+            return next((route for route in fib_dump
+                         if self._match_route_detail(route, ip)),
+                        False)
+
+        for ip in ips:
+            self.assertTrue(_ip_in_route_dump(ip, fib_dump),
+                            'IP {} is not in fib dump.'.format(ip))
+
+    def verify_not_in_route_dump(self, fib_dump, ips):
+
+        def _ip_in_route_dump(ip, fib_dump):
+            return next((route for route in fib_dump
+                         if self._match_route_detail(route, ip)),
+                        False)
+
+        for ip in ips:
+            self.assertFalse(_ip_in_route_dump(ip, fib_dump),
+                             'IP {} is in fib dump.'.format(ip))
+
+    @classmethod
+    def setUpClass(cls):
+        """
+        #. Create and initialize 3 pg interfaces.
+        #. initialize class attributes configured_routes and deleted_routes
+           to store information between tests.
+        """
+        super(TestIPv4FibCrud, cls).setUpClass()
+
+        try:
+            # create 3 pg interfaces
+            cls.create_pg_interfaces(range(3))
+
+            cls.interfaces = list(cls.pg_interfaces)
+
+            # setup all interfaces
+            for i in cls.interfaces:
+                i.admin_up()
+                i.config_ip4()
+                i.resolve_arp()
+
+            cls.configured_routes = []
+            cls.deleted_routes = []
+            cls.pg_if_packet_sizes = [64, 512, 1518, 9018]
+
+        except Exception:
+            super(TestIPv4FibCrud, cls).tearDownClass()
+            raise
+
+    def setUp(self):
+        super(TestIPv4FibCrud, self).setUp()
+        self.reset_packet_infos()
+
+    def test_1_add_routes(self):
+        """ Add 1k routes
+
+        - add 100 routes check with traffic script.
+        """
+        # config 1M FIB entries
+        self.configured_routes.extend(self.config_fib_many_to_one(
+            "10.0.0.0", self.pg0.remote_ip4, 100))
+
+        fib_dump = self.vapi.ip_fib_dump()
+        self.verify_route_dump(fib_dump, self.configured_routes)
+
+        self.stream_1 = self.create_stream(
+            self.pg1, self.pg0, self.configured_routes, 100)
+        self.stream_2 = self.create_stream(
+            self.pg2, self.pg0, self.configured_routes, 100)
+        self.pg1.add_stream(self.stream_1)
+        self.pg2.add_stream(self.stream_2)
+
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        pkts = self.pg0.get_capture(len(self.stream_1) + len(self.stream_2))
+        self.verify_capture(self.pg0, pkts, self.stream_1 + self.stream_2)
+
+    def test_2_del_routes(self):
+        """ Delete 100 routes
+
+        - delete 10 routes check with traffic script.
+        """
+        self.deleted_routes.extend(self.unconfig_fib_many_to_one(
+            "10.0.0.10", self.pg0.remote_ip4, 10))
+        for x in self.deleted_routes:
+            self.configured_routes.remove(x)
+
+        fib_dump = self.vapi.ip_fib_dump()
+        self.verify_route_dump(fib_dump, self.configured_routes)
+
+        self.stream_1 = self.create_stream(
+            self.pg1, self.pg0, self.configured_routes, 100)
+        self.stream_2 = self.create_stream(
+            self.pg2, self.pg0, self.configured_routes, 100)
+        self.stream_3 = self.create_stream(
+            self.pg1, self.pg0, self.deleted_routes, 100)
+        self.stream_4 = self.create_stream(
+            self.pg2, self.pg0, self.deleted_routes, 100)
+        self.pg1.add_stream(self.stream_1 + self.stream_3)
+        self.pg2.add_stream(self.stream_2 + self.stream_4)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        pkts = self.pg0.get_capture(len(self.stream_1) + len(self.stream_2))
+        self.verify_capture(self.pg0, pkts, self.stream_1 + self.stream_2)
+
+    def test_3_add_new_routes(self):
+        """ Add 1k routes
+
+        - re-add 5 routes check with traffic script.
+        - add 100 routes check with traffic script.
+        """
+        tmp = self.config_fib_many_to_one(
+            "10.0.0.10", self.pg0.remote_ip4, 5)
+        self.configured_routes.extend(tmp)
+        for x in tmp:
+            self.deleted_routes.remove(x)
+
+        self.configured_routes.extend(self.config_fib_many_to_one(
+            "10.0.1.0", self.pg0.remote_ip4, 100))
+
+        fib_dump = self.vapi.ip_fib_dump()
+        self.verify_route_dump(fib_dump, self.configured_routes)
+
+        self.stream_1 = self.create_stream(
+            self.pg1, self.pg0, self.configured_routes, 300)
+        self.stream_2 = self.create_stream(
+            self.pg2, self.pg0, self.configured_routes, 300)
+        self.stream_3 = self.create_stream(
+            self.pg1, self.pg0, self.deleted_routes, 100)
+        self.stream_4 = self.create_stream(
+            self.pg2, self.pg0, self.deleted_routes, 100)
+
+        self.pg1.add_stream(self.stream_1 + self.stream_3)
+        self.pg2.add_stream(self.stream_2 + self.stream_4)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        pkts = self.pg0.get_capture(len(self.stream_1) + len(self.stream_2))
+        self.verify_capture(self.pg0, pkts, self.stream_1 + self.stream_2)
+
+    def test_4_del_routes(self):
+        """ Delete 1.5k routes
+
+        - delete 5 routes check with traffic script.
+        - add 100 routes check with traffic script.
+        """
+        self.deleted_routes.extend(self.unconfig_fib_many_to_one(
+            "10.0.0.0", self.pg0.remote_ip4, 15))
+        self.deleted_routes.extend(self.unconfig_fib_many_to_one(
+            "10.0.0.20", self.pg0.remote_ip4, 85))
+        self.deleted_routes.extend(self.unconfig_fib_many_to_one(
+            "10.0.1.0", self.pg0.remote_ip4, 100))
+        fib_dump = self.vapi.ip_fib_dump()
+        self.verify_not_in_route_dump(fib_dump, self.deleted_routes)
+
+
+class TestIPNull(VppTestCase):
+    """ IPv4 routes via NULL """
+
+    def setUp(self):
+        super(TestIPNull, self).setUp()
+
+        # create 2 pg interfaces
+        self.create_pg_interfaces(range(1))
+
+        for i in self.pg_interfaces:
+            i.admin_up()
+            i.config_ip4()
+            i.resolve_arp()
+
+    def tearDown(self):
+        super(TestIPNull, self).tearDown()
+        for i in self.pg_interfaces:
+            i.unconfig_ip4()
+            i.admin_down()
+
+    def test_ip_null(self):
+        """ IP NULL route """
+
+        #
+        # A route via IP NULL that will reply with ICMP unreachables
+        #
+        ip_unreach = VppIpRoute(self, "10.0.0.1", 32, [], is_unreach=1)
+        ip_unreach.add_vpp_config()
+
+        p_unreach = (Ether(src=self.pg0.remote_mac,
+                           dst=self.pg0.local_mac) /
+                     IP(src=self.pg0.remote_ip4, dst="10.0.0.1") /
+                     UDP(sport=1234, dport=1234) /
+                     Raw('\xa5' * 100))
+
+        self.pg0.add_stream(p_unreach)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        rx = self.pg0.get_capture(1)
+        rx = rx[0]
+        icmp = rx[ICMP]
+
+        self.assertEqual(icmptypes[icmp.type], "dest-unreach")
+        self.assertEqual(icmpcodes[icmp.type][icmp.code], "host-unreachable")
+        self.assertEqual(icmp.src, self.pg0.remote_ip4)
+        self.assertEqual(icmp.dst, "10.0.0.1")
+
+        #
+        # ICMP replies are rate limited. so sit and spin.
+        #
+        self.sleep(1)
+
+        #
+        # A route via IP NULL that will reply with ICMP prohibited
+        #
+        ip_prohibit = VppIpRoute(self, "10.0.0.2", 32, [], is_prohibit=1)
+        ip_prohibit.add_vpp_config()
+
+        p_prohibit = (Ether(src=self.pg0.remote_mac,
+                            dst=self.pg0.local_mac) /
+                      IP(src=self.pg0.remote_ip4, dst="10.0.0.2") /
+                      UDP(sport=1234, dport=1234) /
+                      Raw('\xa5' * 100))
+
+        self.pg0.add_stream(p_prohibit)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        rx = self.pg0.get_capture(1)
+
+        rx = rx[0]
+        icmp = rx[ICMP]
+
+        self.assertEqual(icmptypes[icmp.type], "dest-unreach")
+        self.assertEqual(icmpcodes[icmp.type][icmp.code], "host-prohibited")
+        self.assertEqual(icmp.src, self.pg0.remote_ip4)
+        self.assertEqual(icmp.dst, "10.0.0.2")
+
+
+class TestIPDisabled(VppTestCase):
+    """ IPv4 disabled """
+
+    def setUp(self):
+        super(TestIPDisabled, self).setUp()
+
+        # create 2 pg interfaces
+        self.create_pg_interfaces(range(2))
+
+        # PG0 is IP enalbed
+        self.pg0.admin_up()
+        self.pg0.config_ip4()
+        self.pg0.resolve_arp()
+
+        # PG 1 is not IP enabled
+        self.pg1.admin_up()
+
+    def tearDown(self):
+        super(TestIPDisabled, self).tearDown()
+        for i in self.pg_interfaces:
+            i.unconfig_ip4()
+            i.admin_down()
+
+    def send_and_assert_no_replies(self, intf, pkts, remark):
+        intf.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        for i in self.pg_interfaces:
+            i.get_capture(0)
+            i.assert_nothing_captured(remark=remark)
+
+    def test_ip_disabled(self):
+        """ IP Disabled """
+
+        #
+        # An (S,G).
+        # one accepting interface, pg0, 2 forwarding interfaces
+        #
+        route_232_1_1_1 = VppIpMRoute(
+            self,
+            "0.0.0.0",
+            "232.1.1.1", 32,
+            MRouteEntryFlags.MFIB_ENTRY_FLAG_NONE,
+            [VppMRoutePath(self.pg1.sw_if_index,
+                           MRouteItfFlags.MFIB_ITF_FLAG_ACCEPT),
+             VppMRoutePath(self.pg0.sw_if_index,
+                           MRouteItfFlags.MFIB_ITF_FLAG_FORWARD)])
+        route_232_1_1_1.add_vpp_config()
+
+        pu = (Ether(src=self.pg1.remote_mac,
+                    dst=self.pg1.local_mac) /
+              IP(src="10.10.10.10", dst=self.pg0.remote_ip4) /
+              UDP(sport=1234, dport=1234) /
+              Raw('\xa5' * 100))
+        pm = (Ether(src=self.pg1.remote_mac,
+                    dst=self.pg1.local_mac) /
+              IP(src="10.10.10.10", dst="232.1.1.1") /
+              UDP(sport=1234, dport=1234) /
+              Raw('\xa5' * 100))
+
+        #
+        # PG1 does not forward IP traffic
+        #
+        self.send_and_assert_no_replies(self.pg1, pu, "IP disabled")
+        self.send_and_assert_no_replies(self.pg1, pm, "IP disabled")
+
+        #
+        # IP enable PG1
+        #
+        self.pg1.config_ip4()
+
+        #
+        # Now we get packets through
+        #
+        self.pg1.add_stream(pu)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg0.get_capture(1)
+
+        self.pg1.add_stream(pm)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg0.get_capture(1)
+
+        #
+        # Disable PG1
+        #
+        self.pg1.unconfig_ip4()
+
+        #
+        # PG1 does not forward IP traffic
+        #
+        self.send_and_assert_no_replies(self.pg1, pu, "IP disabled")
+        self.send_and_assert_no_replies(self.pg1, pm, "IP disabled")
+
+
+class TestIPSubNets(VppTestCase):
+    """ IPv4 Subnets """
+
+    def setUp(self):
+        super(TestIPSubNets, self).setUp()
+
+        # create a 2 pg interfaces
+        self.create_pg_interfaces(range(2))
+
+        # pg0 we will use to experiemnt
+        self.pg0.admin_up()
+
+        # pg1 is setup normally
+        self.pg1.admin_up()
+        self.pg1.config_ip4()
+        self.pg1.resolve_arp()
+
+    def tearDown(self):
+        super(TestIPSubNets, self).tearDown()
+        for i in self.pg_interfaces:
+            i.admin_down()
+
+    def send_and_assert_no_replies(self, intf, pkts, remark):
+        intf.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        for i in self.pg_interfaces:
+            i.get_capture(0)
+            i.assert_nothing_captured(remark=remark)
+
+    def test_ip_sub_nets(self):
+        """ IP Sub Nets """
+
+        #
+        # Configure a covering route to forward so we know
+        # when we are dropping
+        #
+        cover_route = VppIpRoute(self, "10.0.0.0", 8,
+                                 [VppRoutePath(self.pg1.remote_ip4,
+                                               self.pg1.sw_if_index)])
+        cover_route.add_vpp_config()
+
+        p = (Ether(src=self.pg1.remote_mac,
+                   dst=self.pg1.local_mac) /
+             IP(dst="10.10.10.10", src=self.pg0.local_ip4) /
+             UDP(sport=1234, dport=1234) /
+             Raw('\xa5' * 100))
+
+        self.pg1.add_stream(p)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg1.get_capture(1)
+
+        #
+        # Configure some non-/24 subnets on an IP interface
+        #
+        ip_addr_n = socket.inet_pton(socket.AF_INET, "10.10.10.10")
+
+        self.vapi.sw_interface_add_del_address(self.pg0.sw_if_index,
+                                               ip_addr_n,
+                                               16)
+
+        pn = (Ether(src=self.pg1.remote_mac,
+                    dst=self.pg1.local_mac) /
+              IP(dst="10.10.0.0", src=self.pg0.local_ip4) /
+              UDP(sport=1234, dport=1234) /
+              Raw('\xa5' * 100))
+        pb = (Ether(src=self.pg1.remote_mac,
+                    dst=self.pg1.local_mac) /
+              IP(dst="10.10.255.255", src=self.pg0.local_ip4) /
+              UDP(sport=1234, dport=1234) /
+              Raw('\xa5' * 100))
+
+        self.send_and_assert_no_replies(self.pg1, pn, "IP Network address")
+        self.send_and_assert_no_replies(self.pg1, pb, "IP Broadcast address")
+
+        # remove the sub-net and we are forwarding via the cover again
+        self.vapi.sw_interface_add_del_address(self.pg0.sw_if_index,
+                                               ip_addr_n,
+                                               16,
+                                               is_add=0)
+        self.pg1.add_stream(pn)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg1.get_capture(1)
+        self.pg1.add_stream(pb)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg1.get_capture(1)
+
+        #
+        # A /31 is a special case where the 'other-side' is an attached host
+        # packets to that peer generate ARP requests
+        #
+        ip_addr_n = socket.inet_pton(socket.AF_INET, "10.10.10.10")
+
+        self.vapi.sw_interface_add_del_address(self.pg0.sw_if_index,
+                                               ip_addr_n,
+                                               31)
+
+        pn = (Ether(src=self.pg1.remote_mac,
+                    dst=self.pg1.local_mac) /
+              IP(dst="10.10.10.11", src=self.pg0.local_ip4) /
+              UDP(sport=1234, dport=1234) /
+              Raw('\xa5' * 100))
+
+        self.pg1.add_stream(pn)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg0.get_capture(1)
+        rx[ARP]
+
+        # remove the sub-net and we are forwarding via the cover again
+        self.vapi.sw_interface_add_del_address(self.pg0.sw_if_index,
+                                               ip_addr_n,
+                                               31,
+                                               is_add=0)
+        self.pg1.add_stream(pn)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg1.get_capture(1)
+
+
+class TestIPLoadBalance(VppTestCase):
+    """ IPv4 Load-Balancing """
+
+    def setUp(self):
+        super(TestIPLoadBalance, self).setUp()
+
+        self.create_pg_interfaces(range(5))
+
+        for i in self.pg_interfaces:
+            i.admin_up()
+            i.config_ip4()
+            i.resolve_arp()
+            i.enable_mpls()
+
+    def tearDown(self):
+        super(TestIPLoadBalance, self).tearDown()
+        for i in self.pg_interfaces:
+            i.disable_mpls()
+            i.unconfig_ip4()
+            i.admin_down()
+
+    def send_and_expect_load_balancing(self, input, pkts, outputs):
+        input.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        for oo in outputs:
+            rx = oo._get_capture(1)
+            self.assertNotEqual(0, len(rx))
+
+    def test_ip_load_balance(self):
+        """ IP Load-Balancing """
+
+        #
+        # An array of packets that differ only in the destination port
+        #
+        port_ip_pkts = []
+        port_mpls_pkts = []
+
+        #
+        # An array of packets that differ only in the source address
+        #
+        src_ip_pkts = []
+        src_mpls_pkts = []
+
+        for ii in range(65):
+            port_ip_hdr = (IP(dst="10.0.0.1", src="20.0.0.1") /
+                           UDP(sport=1234, dport=1234 + ii) /
+                           Raw('\xa5' * 100))
+            port_ip_pkts.append((Ether(src=self.pg0.remote_mac,
+                                       dst=self.pg0.local_mac) /
+                                 port_ip_hdr))
+            port_mpls_pkts.append((Ether(src=self.pg0.remote_mac,
+                                         dst=self.pg0.local_mac) /
+                                   MPLS(label=66, ttl=2) /
+                                   port_ip_hdr))
+
+            src_ip_hdr = (IP(dst="10.0.0.1", src="20.0.0.%d" % ii) /
+                          UDP(sport=1234, dport=1234) /
+                          Raw('\xa5' * 100))
+            src_ip_pkts.append((Ether(src=self.pg0.remote_mac,
+                                      dst=self.pg0.local_mac) /
+                                src_ip_hdr))
+            src_mpls_pkts.append((Ether(src=self.pg0.remote_mac,
+                                        dst=self.pg0.local_mac) /
+                                  MPLS(label=66, ttl=2) /
+                                  src_ip_hdr))
+
+        route_10_0_0_1 = VppIpRoute(self, "10.0.0.1", 32,
+                                    [VppRoutePath(self.pg1.remote_ip4,
+                                                  self.pg1.sw_if_index),
+                                     VppRoutePath(self.pg2.remote_ip4,
+                                                  self.pg2.sw_if_index)])
+        route_10_0_0_1.add_vpp_config()
+
+        binding = VppMplsIpBind(self, 66, "10.0.0.1", 32)
+        binding.add_vpp_config()
+
+        #
+        # inject the packet on pg0 - expect load-balancing across the 2 paths
+        #  - since the default hash config is to use IP src,dst and port
+        #    src,dst
+        # We are not going to ensure equal amounts of packets across each link,
+        # since the hash algorithm is statistical and therefore this can never
+        # be guaranteed. But wuth 64 different packets we do expect some
+        # balancing. So instead just ensure there is traffic on each link.
+        #
+        self.send_and_expect_load_balancing(self.pg0, port_ip_pkts,
+                                            [self.pg1, self.pg2])
+        self.send_and_expect_load_balancing(self.pg0, src_ip_pkts,
+                                            [self.pg1, self.pg2])
+        self.send_and_expect_load_balancing(self.pg0, port_mpls_pkts,
+                                            [self.pg1, self.pg2])
+        self.send_and_expect_load_balancing(self.pg0, src_mpls_pkts,
+                                            [self.pg1, self.pg2])
+
+        #
+        # change the flow hash config so it's only IP src,dst
+        #  - now only the stream with differing source address will
+        #    load-balance
+        #
+        self.vapi.set_ip_flow_hash(0, src=1, dst=1, sport=0, dport=0)
+
+        self.send_and_expect_load_balancing(self.pg0, src_ip_pkts,
+                                            [self.pg1, self.pg2])
+        self.send_and_expect_load_balancing(self.pg0, src_mpls_pkts,
+                                            [self.pg1, self.pg2])
+
+        self.pg0.add_stream(port_ip_pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        rx = self.pg2.get_capture(len(port_ip_pkts))
+
+        #
+        # change the flow hash config back to defaults
+        #
+        self.vapi.set_ip_flow_hash(0, src=1, dst=1, sport=1, dport=1)
+
+        #
+        # Recursive prefixes
+        #  - testing that 2 stages of load-balancing occurs and there is no
+        #    polarisation (i.e. only 2 of 4 paths are used)
+        #
+        port_pkts = []
+        src_pkts = []
+
+        for ii in range(257):
+            port_pkts.append((Ether(src=self.pg0.remote_mac,
+                                    dst=self.pg0.local_mac) /
+                              IP(dst="1.1.1.1", src="20.0.0.1") /
+                              UDP(sport=1234, dport=1234 + ii) /
+                              Raw('\xa5' * 100)))
+            src_pkts.append((Ether(src=self.pg0.remote_mac,
+                                   dst=self.pg0.local_mac) /
+                             IP(dst="1.1.1.1", src="20.0.0.%d" % ii) /
+                             UDP(sport=1234, dport=1234) /
+                             Raw('\xa5' * 100)))
+
+        route_10_0_0_2 = VppIpRoute(self, "10.0.0.2", 32,
+                                    [VppRoutePath(self.pg3.remote_ip4,
+                                                  self.pg3.sw_if_index),
+                                     VppRoutePath(self.pg4.remote_ip4,
+                                                  self.pg4.sw_if_index)])
+        route_10_0_0_2.add_vpp_config()
+
+        route_1_1_1_1 = VppIpRoute(self, "1.1.1.1", 32,
+                                   [VppRoutePath("10.0.0.2", 0xffffffff),
+                                    VppRoutePath("10.0.0.1", 0xffffffff)])
+        route_1_1_1_1.add_vpp_config()
+
+        #
+        # inject the packet on pg0 - expect load-balancing across all 4 paths
+        #
+        self.vapi.cli("clear trace")
+        self.send_and_expect_load_balancing(self.pg0, port_pkts,
+                                            [self.pg1, self.pg2,
+                                             self.pg3, self.pg4])
+        self.send_and_expect_load_balancing(self.pg0, src_pkts,
+                                            [self.pg1, self.pg2,
+                                             self.pg3, self.pg4])
+
 if __name__ == '__main__':
     unittest.main(testRunner=VppTestRunner)