ip: use IPv6 flowlabel in flow hash computation
[vpp.git] / test / test_ip4.py
index a043be8..a428db3 100644 (file)
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 import binascii
 import random
 import socket
@@ -13,15 +13,16 @@ from six import moves
 
 from framework import VppTestCase, VppTestRunner
 from util import ppp
-from vpp_ip import VppIpPrefix
 from vpp_ip_route import VppIpRoute, VppRoutePath, VppIpMRoute, \
-    VppMRoutePath, MRouteItfFlags, MRouteEntryFlags, VppMplsIpBind, \
+    VppMRoutePath, VppMplsIpBind, \
     VppMplsTable, VppIpTable, FibPathType, find_route, \
-    VppIpInterfaceAddress
-from vpp_ip import VppIpAddress
+    VppIpInterfaceAddress, find_route_in_dump, find_mroute_in_dump
+from vpp_ip import VppIpPuntPolicer, VppIpPuntRedirect
 from vpp_sub_interface import VppSubInterface, VppDot1QSubint, VppDot1ADSubint
 from vpp_papi import VppEnum
 from vpp_neighbor import VppNeighbor
+from vpp_lo_interface import VppLoInterface
+from vpp_policer import VppPolicer
 
 NUM_PKTS = 67
 
@@ -90,7 +91,7 @@ class TestIPv4(VppTestCase):
         super(TestIPv4, self).tearDown()
 
     def show_commands_at_teardown(self):
-        self.logger.info(self.vapi.cli("show ip arp"))
+        self.logger.info(self.vapi.cli("show ip4 neighbors"))
         # info(self.vapi.cli("show ip fib"))  # many entries
 
     def modify_packet(self, src_if, packet_size, pkt):
@@ -214,6 +215,80 @@ class TestIPv4(VppTestCase):
             self.verify_capture(i, pkts)
 
 
+class TestIPv4RouteLookup(VppTestCase):
+    """ IPv4 Route Lookup Test Case """
+    routes = []
+
+    def route_lookup(self, prefix, exact):
+        return self.vapi.api(self.vapi.papi.ip_route_lookup,
+                             {
+                                 'table_id': 0,
+                                 'exact': exact,
+                                 'prefix': prefix,
+                             })
+
+    @classmethod
+    def setUpClass(cls):
+        super(TestIPv4RouteLookup, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(TestIPv4RouteLookup, cls).tearDownClass()
+
+    def setUp(self):
+        super(TestIPv4RouteLookup, self).setUp()
+
+        drop_nh = VppRoutePath("127.0.0.1", 0xffffffff,
+                               type=FibPathType.FIB_PATH_TYPE_DROP)
+
+        # Add 3 routes
+        r = VppIpRoute(self, "1.1.0.0", 16, [drop_nh])
+        r.add_vpp_config()
+        self.routes.append(r)
+
+        r = VppIpRoute(self, "1.1.1.0", 24, [drop_nh])
+        r.add_vpp_config()
+        self.routes.append(r)
+
+        r = VppIpRoute(self, "1.1.1.1", 32, [drop_nh])
+        r.add_vpp_config()
+        self.routes.append(r)
+
+    def tearDown(self):
+        # Remove the routes we added
+        for r in self.routes:
+            r.remove_vpp_config()
+
+        super(TestIPv4RouteLookup, self).tearDown()
+
+    def test_exact_match(self):
+        # Verify we find the host route
+        prefix = "1.1.1.1/32"
+        result = self.route_lookup(prefix, True)
+        assert (prefix == str(result.route.prefix))
+
+        # Verify we find a middle prefix route
+        prefix = "1.1.1.0/24"
+        result = self.route_lookup(prefix, True)
+        assert (prefix == str(result.route.prefix))
+
+        # Verify we do not find an available LPM.
+        with self.vapi.assert_negative_api_retval():
+            self.route_lookup("1.1.1.2/32", True)
+
+    def test_longest_prefix_match(self):
+        # verify we find lpm
+        lpm_prefix = "1.1.1.0/24"
+        result = self.route_lookup("1.1.1.2/32", False)
+        assert (lpm_prefix == str(result.route.prefix))
+
+        # Verify we find the exact when not requested
+        result = self.route_lookup(lpm_prefix, False)
+        assert (lpm_prefix == str(result.route.prefix))
+
+        # Can't seem to delete the default route so no negative LPM test.
+
+
 class TestIPv4IfAddrRoute(VppTestCase):
     """ IPv4 Interface Addr Route Test Case """
 
@@ -258,11 +333,9 @@ class TestIPv4IfAddrRoute(VppTestCase):
         """
 
         # create two addresses, verify route not present
-        if_addr1 = VppIpInterfaceAddress(self, self.pg0,
-                                         VppIpAddress("10.10.10.10"), 24)
-        if_addr2 = VppIpInterfaceAddress(self, self.pg0,
-                                         VppIpAddress("10.10.10.20"), 24)
-        self.assertFalse(if_addr1.query_vpp_config())  # 10.10.10.0/24
+        if_addr1 = VppIpInterfaceAddress(self, self.pg0, "10.10.10.10", 24)
+        if_addr2 = VppIpInterfaceAddress(self, self.pg0, "10.10.10.20", 24)
+        self.assertFalse(if_addr1.query_vpp_config())  # 10.10.10.10/24
         self.assertFalse(find_route(self, "10.10.10.10", 32))
         self.assertFalse(find_route(self, "10.10.10.20", 32))
         self.assertFalse(find_route(self, "10.10.10.255", 32))
@@ -270,7 +343,7 @@ class TestIPv4IfAddrRoute(VppTestCase):
 
         # configure first address, verify route present
         if_addr1.add_vpp_config()
-        self.assertTrue(if_addr1.query_vpp_config())  # 10.10.10.0/24
+        self.assertTrue(if_addr1.query_vpp_config())  # 10.10.10.10/24
         self.assertTrue(find_route(self, "10.10.10.10", 32))
         self.assertFalse(find_route(self, "10.10.10.20", 32))
         self.assertTrue(find_route(self, "10.10.10.255", 32))
@@ -279,7 +352,8 @@ class TestIPv4IfAddrRoute(VppTestCase):
         # configure second address, delete first, verify route not removed
         if_addr2.add_vpp_config()
         if_addr1.remove_vpp_config()
-        self.assertTrue(if_addr1.query_vpp_config())  # 10.10.10.0/24
+        self.assertFalse(if_addr1.query_vpp_config())  # 10.10.10.10/24
+        self.assertTrue(if_addr2.query_vpp_config())  # 10.10.10.20/24
         self.assertFalse(find_route(self, "10.10.10.10", 32))
         self.assertTrue(find_route(self, "10.10.10.20", 32))
         self.assertTrue(find_route(self, "10.10.10.255", 32))
@@ -287,7 +361,7 @@ class TestIPv4IfAddrRoute(VppTestCase):
 
         # delete second address, verify route removed
         if_addr2.remove_vpp_config()
-        self.assertFalse(if_addr1.query_vpp_config())  # 10.10.10.0/24
+        self.assertFalse(if_addr2.query_vpp_config())  # 10.10.10.20/24
         self.assertFalse(find_route(self, "10.10.10.10", 32))
         self.assertFalse(find_route(self, "10.10.10.20", 32))
         self.assertFalse(find_route(self, "10.10.10.255", 32))
@@ -338,6 +412,24 @@ class TestIPv4IfAddrRoute(VppTestCase):
         fib4_dump = self.vapi.ip_route_dump(0)
         self.assertTrue(lo_if.is_ip4_entry_in_fib_dump(fib4_dump))
 
+    def test_ipv4_ifaddr_del(self):
+        """ Delete an interface address that does not exist """
+
+        loopbacks = self.create_loopback_interfaces(1)
+        lo = self.lo_interfaces[0]
+
+        lo.config_ip4()
+        lo.admin_up()
+
+        #
+        # try and remove pg0's subnet from lo
+        #
+        with self.vapi.assert_negative_api_retval():
+            self.vapi.sw_interface_add_del_address(
+                sw_if_index=lo.sw_if_index,
+                prefix=self.pg0.local_ip4_prefix,
+                is_add=0)
+
 
 class TestICMPEcho(VppTestCase):
     """ ICMP Echo Test Case """
@@ -451,11 +543,11 @@ class TestIPv4FibCrud(VppTestCase):
         pkts = []
 
         for _ in range(count):
-            dst_addr = random.choice(routes).prefix.address
+            dst_addr = random.choice(routes).prefix.network_address
             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) /
+                 IP(src=src_if.remote_ip4, dst=str(dst_addr)) /
                  UDP(sport=1234, dport=1234) /
                  Raw(payload))
             info.data = p.copy()
@@ -491,11 +583,15 @@ class TestIPv4FibCrud(VppTestCase):
 
     def verify_route_dump(self, routes):
         for r in routes:
-            self.assertTrue(find_route(self, r.prefix.address, r.prefix.len))
+            self.assertTrue(find_route(self,
+                                       r.prefix.network_address,
+                                       r.prefix.prefixlen))
 
     def verify_not_in_route_dump(self, routes):
         for r in routes:
-            self.assertFalse(find_route(self, r.prefix.address, r.prefix.len))
+            self.assertFalse(find_route(self,
+                                        r.prefix.network_address,
+                                        r.prefix.prefixlen))
 
     @classmethod
     def setUpClass(cls):
@@ -801,6 +897,9 @@ class TestIPDisabled(VppTestCase):
     def test_ip_disabled(self):
         """ IP Disabled """
 
+        MRouteItfFlags = VppEnum.vl_api_mfib_itf_flags_t
+        MRouteEntryFlags = VppEnum.vl_api_mfib_entry_flags_t
+
         #
         # An (S,G).
         # one accepting interface, pg0, 2 forwarding interfaces
@@ -809,11 +908,11 @@ class TestIPDisabled(VppTestCase):
             self,
             "0.0.0.0",
             "232.1.1.1", 32,
-            MRouteEntryFlags.MFIB_ENTRY_FLAG_NONE,
+            MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
             [VppMRoutePath(self.pg1.sw_if_index,
-                           MRouteItfFlags.MFIB_ITF_FLAG_ACCEPT),
+                           MRouteItfFlags.MFIB_API_ITF_FLAG_ACCEPT),
              VppMRoutePath(self.pg0.sw_if_index,
-                           MRouteItfFlags.MFIB_ITF_FLAG_FORWARD)])
+                           MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD)])
         route_232_1_1_1.add_vpp_config()
 
         pu = (Ether(src=self.pg1.remote_mac,
@@ -923,7 +1022,7 @@ class TestIPSubNets(VppTestCase):
 
         self.vapi.sw_interface_add_del_address(
             sw_if_index=self.pg0.sw_if_index,
-            prefix=VppIpPrefix("10.10.10.10", 16).encode())
+            prefix="10.10.10.10/16")
 
         pn = (Ether(src=self.pg1.remote_mac,
                     dst=self.pg1.local_mac) /
@@ -942,7 +1041,8 @@ class TestIPSubNets(VppTestCase):
         # remove the sub-net and we are forwarding via the cover again
         self.vapi.sw_interface_add_del_address(
             sw_if_index=self.pg0.sw_if_index,
-            prefix=VppIpPrefix("10.10.10.10", 16).encode(), is_add=0)
+            prefix="10.10.10.10/16",
+            is_add=0)
 
         self.pg1.add_stream(pn)
         self.pg_enable_capture(self.pg_interfaces)
@@ -961,7 +1061,7 @@ class TestIPSubNets(VppTestCase):
 
         self.vapi.sw_interface_add_del_address(
             sw_if_index=self.pg0.sw_if_index,
-            prefix=VppIpPrefix("10.10.10.10", 31).encode())
+            prefix="10.10.10.10/31")
 
         pn = (Ether(src=self.pg1.remote_mac,
                     dst=self.pg1.local_mac) /
@@ -978,7 +1078,7 @@ class TestIPSubNets(VppTestCase):
         # remove the sub-net and we are forwarding via the cover again
         self.vapi.sw_interface_add_del_address(
             sw_if_index=self.pg0.sw_if_index,
-            prefix=VppIpPrefix("10.10.10.10", 31).encode(), is_add=0)
+            prefix="10.10.10.10/31", is_add=0)
 
         self.pg1.add_stream(pn)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1038,6 +1138,9 @@ class TestIPLoadBalance(VppTestCase):
     def test_ip_load_balance(self):
         """ IP Load-Balancing """
 
+        fhc = VppEnum.vl_api_ip_flow_hash_config_t
+        af = VppEnum.vl_api_address_family_t
+
         #
         # An array of packets that differ only in the destination port
         #
@@ -1106,7 +1209,12 @@ class TestIPLoadBalance(VppTestCase):
         #  - now only the stream with differing source address will
         #    load-balance
         #
-        self.vapi.set_ip_flow_hash(vrf_id=0, src=1, dst=1, sport=0, dport=0)
+        self.vapi.set_ip_flow_hash_v2(
+            af=af.ADDRESS_IP4,
+            table_id=0,
+            flow_hash_config=(fhc.IP_API_FLOW_HASH_SRC_IP |
+                              fhc.IP_API_FLOW_HASH_DST_IP |
+                              fhc.IP_API_FLOW_HASH_PROTO))
 
         self.send_and_expect_load_balancing(self.pg0, src_ip_pkts,
                                             [self.pg1, self.pg2])
@@ -1118,7 +1226,8 @@ class TestIPLoadBalance(VppTestCase):
         #
         # change the flow hash config back to defaults
         #
-        self.vapi.set_ip_flow_hash(vrf_id=0, src=1, dst=1, sport=1, dport=1)
+        self.vapi.set_ip_flow_hash(vrf_id=0, src=1, dst=1,
+                                   proto=1, sport=1, dport=1)
 
         #
         # Recursive prefixes
@@ -1378,18 +1487,19 @@ class TestIPPunt(VppTestCase):
         # Configure a punt redirect via pg1.
         #
         nh_addr = self.pg1.remote_ip4
-        self.vapi.ip_punt_redirect(self.pg0.sw_if_index,
-                                   self.pg1.sw_if_index,
-                                   nh_addr)
+        ip_punt_redirect = VppIpPuntRedirect(self, self.pg0.sw_if_index,
+                                             self.pg1.sw_if_index, nh_addr)
+        ip_punt_redirect.add_vpp_config()
 
         self.send_and_expect(self.pg0, pkts, self.pg1)
 
         #
         # add a policer
         #
-        policer = self.vapi.policer_add_del(b"ip4-punt", 400, 0, 10, 0,
-                                            rate_type=1)
-        self.vapi.ip_punt_police(policer.policer_index)
+        policer = VppPolicer(self, "ip4-punt", 400, 0, 10, 0, rate_type=1)
+        policer.add_vpp_config()
+        ip_punt_policer = VppIpPuntPolicer(self, policer.policer_index)
+        ip_punt_policer.add_vpp_config()
 
         self.vapi.cli("clear trace")
         self.pg0.add_stream(pkts)
@@ -1407,33 +1517,25 @@ class TestIPPunt(VppTestCase):
         #
         # remove the policer. back to full rx
         #
-        self.vapi.ip_punt_police(policer.policer_index, is_add=0)
-        self.vapi.policer_add_del(b"ip4-punt", 400, 0, 10, 0,
-                                  rate_type=1, is_add=0)
+        ip_punt_policer.remove_vpp_config()
+        policer.remove_vpp_config()
         self.send_and_expect(self.pg0, pkts, self.pg1)
 
         #
         # remove the redirect. expect full drop.
         #
-        self.vapi.ip_punt_redirect(self.pg0.sw_if_index,
-                                   self.pg1.sw_if_index,
-                                   nh_addr,
-                                   is_add=0)
+        ip_punt_redirect.remove_vpp_config()
         self.send_and_assert_no_replies(self.pg0, pkts,
                                         "IP no punt config")
 
         #
         # Add a redirect that is not input port selective
         #
-        self.vapi.ip_punt_redirect(0xffffffff,
-                                   self.pg1.sw_if_index,
-                                   nh_addr)
+        ip_punt_redirect = VppIpPuntRedirect(self, 0xffffffff,
+                                             self.pg1.sw_if_index, nh_addr)
+        ip_punt_redirect.add_vpp_config()
         self.send_and_expect(self.pg0, pkts, self.pg1)
-
-        self.vapi.ip_punt_redirect(0xffffffff,
-                                   self.pg1.sw_if_index,
-                                   nh_addr,
-                                   is_add=0)
+        ip_punt_redirect.remove_vpp_config()
 
     def test_ip_punt_dump(self):
         """ IP4 punt redirect dump"""
@@ -1442,22 +1544,22 @@ class TestIPPunt(VppTestCase):
         # Configure a punt redirects
         #
         nh_address = self.pg3.remote_ip4
-        self.vapi.ip_punt_redirect(self.pg0.sw_if_index,
-                                   self.pg3.sw_if_index,
-                                   nh_address)
-        self.vapi.ip_punt_redirect(self.pg1.sw_if_index,
-                                   self.pg3.sw_if_index,
-                                   nh_address)
-        self.vapi.ip_punt_redirect(self.pg2.sw_if_index,
-                                   self.pg3.sw_if_index,
-                                   '0.0.0.0')
+        ipr_03 = VppIpPuntRedirect(self, self.pg0.sw_if_index,
+                                   self.pg3.sw_if_index, nh_address)
+        ipr_13 = VppIpPuntRedirect(self, self.pg1.sw_if_index,
+                                   self.pg3.sw_if_index, nh_address)
+        ipr_23 = VppIpPuntRedirect(self, self.pg2.sw_if_index,
+                                   self.pg3.sw_if_index, "0.0.0.0")
+        ipr_03.add_vpp_config()
+        ipr_13.add_vpp_config()
+        ipr_23.add_vpp_config()
 
         #
         # Dump pg0 punt redirects
         #
-        punts = self.vapi.ip_punt_redirect_dump(self.pg0.sw_if_index)
-        for p in punts:
-            self.assertEqual(p.punt.rx_sw_if_index, self.pg0.sw_if_index)
+        self.assertTrue(ipr_03.query_vpp_config())
+        self.assertTrue(ipr_13.query_vpp_config())
+        self.assertTrue(ipr_23.query_vpp_config())
 
         #
         # Dump punt redirects for all interfaces
@@ -1959,5 +2061,366 @@ class TestIPv4Frag(VppTestCase):
         self.assert_equal(payload, saved_payload, "payload")
 
 
+class TestIPReplace(VppTestCase):
+    """ IPv4 Table Replace """
+
+    @classmethod
+    def setUpClass(cls):
+        super(TestIPReplace, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(TestIPReplace, cls).tearDownClass()
+
+    def setUp(self):
+        super(TestIPReplace, self).setUp()
+
+        self.create_pg_interfaces(range(4))
+
+        table_id = 1
+        self.tables = []
+
+        for i in self.pg_interfaces:
+            i.admin_up()
+            i.config_ip4()
+            i.resolve_arp()
+            i.generate_remote_hosts(2)
+            self.tables.append(VppIpTable(self, table_id).add_vpp_config())
+            table_id += 1
+
+    def tearDown(self):
+        super(TestIPReplace, self).tearDown()
+        for i in self.pg_interfaces:
+            i.admin_down()
+            i.unconfig_ip4()
+
+    def test_replace(self):
+        """ IP Table Replace """
+
+        MRouteItfFlags = VppEnum.vl_api_mfib_itf_flags_t
+        MRouteEntryFlags = VppEnum.vl_api_mfib_entry_flags_t
+        N_ROUTES = 20
+        links = [self.pg0, self.pg1, self.pg2, self.pg3]
+        routes = [[], [], [], []]
+
+        # load up the tables with some routes
+        for ii, t in enumerate(self.tables):
+            for jj in range(N_ROUTES):
+                uni = VppIpRoute(
+                    self, "10.0.0.%d" % jj, 32,
+                    [VppRoutePath(links[ii].remote_hosts[0].ip4,
+                                  links[ii].sw_if_index),
+                     VppRoutePath(links[ii].remote_hosts[1].ip4,
+                                  links[ii].sw_if_index)],
+                    table_id=t.table_id).add_vpp_config()
+                multi = VppIpMRoute(
+                    self, "0.0.0.0",
+                    "239.0.0.%d" % jj, 32,
+                    MRouteEntryFlags.MFIB_API_ENTRY_FLAG_NONE,
+                    [VppMRoutePath(self.pg0.sw_if_index,
+                                   MRouteItfFlags.MFIB_API_ITF_FLAG_ACCEPT),
+                     VppMRoutePath(self.pg1.sw_if_index,
+                                   MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD),
+                     VppMRoutePath(self.pg2.sw_if_index,
+                                   MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD),
+                     VppMRoutePath(self.pg3.sw_if_index,
+                                   MRouteItfFlags.MFIB_API_ITF_FLAG_FORWARD)],
+                    table_id=t.table_id).add_vpp_config()
+                routes[ii].append({'uni': uni,
+                                   'multi': multi})
+
+        #
+        # replace the tables a few times
+        #
+        for kk in range(3):
+            # replace_begin each table
+            for t in self.tables:
+                t.replace_begin()
+
+            # all the routes are still there
+            for ii, t in enumerate(self.tables):
+                dump = t.dump()
+                mdump = t.mdump()
+                for r in routes[ii]:
+                    self.assertTrue(find_route_in_dump(dump, r['uni'], t))
+                    self.assertTrue(find_mroute_in_dump(mdump, r['multi'], t))
+
+            # redownload the even numbered routes
+            for ii, t in enumerate(self.tables):
+                for jj in range(0, N_ROUTES, 2):
+                    routes[ii][jj]['uni'].add_vpp_config()
+                    routes[ii][jj]['multi'].add_vpp_config()
+
+            # signal each table replace_end
+            for t in self.tables:
+                t.replace_end()
+
+            # we should find the even routes, but not the odd
+            for ii, t in enumerate(self.tables):
+                dump = t.dump()
+                mdump = t.mdump()
+                for jj in range(0, N_ROUTES, 2):
+                    self.assertTrue(find_route_in_dump(
+                        dump, routes[ii][jj]['uni'], t))
+                    self.assertTrue(find_mroute_in_dump(
+                        mdump, routes[ii][jj]['multi'], t))
+                for jj in range(1, N_ROUTES - 1, 2):
+                    self.assertFalse(find_route_in_dump(
+                        dump, routes[ii][jj]['uni'], t))
+                    self.assertFalse(find_mroute_in_dump(
+                        mdump, routes[ii][jj]['multi'], t))
+
+            # reload all the routes
+            for ii, t in enumerate(self.tables):
+                for r in routes[ii]:
+                    r['uni'].add_vpp_config()
+                    r['multi'].add_vpp_config()
+
+            # all the routes are still there
+            for ii, t in enumerate(self.tables):
+                dump = t.dump()
+                mdump = t.mdump()
+                for r in routes[ii]:
+                    self.assertTrue(find_route_in_dump(dump, r['uni'], t))
+                    self.assertTrue(find_mroute_in_dump(mdump, r['multi'], t))
+
+        #
+        # finally flush the tables for good measure
+        #
+        for t in self.tables:
+            t.flush()
+            self.assertEqual(len(t.dump()), 5)
+            self.assertEqual(len(t.mdump()), 3)
+
+
+class TestIPCover(VppTestCase):
+    """ IPv4 Table Cover """
+
+    @classmethod
+    def setUpClass(cls):
+        super(TestIPCover, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(TestIPCover, cls).tearDownClass()
+
+    def setUp(self):
+        super(TestIPCover, self).setUp()
+
+        self.create_pg_interfaces(range(4))
+
+        table_id = 1
+        self.tables = []
+
+        for i in self.pg_interfaces:
+            i.admin_up()
+            i.config_ip4()
+            i.resolve_arp()
+            i.generate_remote_hosts(2)
+            self.tables.append(VppIpTable(self, table_id).add_vpp_config())
+            table_id += 1
+
+    def tearDown(self):
+        super(TestIPCover, self).tearDown()
+        for i in self.pg_interfaces:
+            i.admin_down()
+            i.unconfig_ip4()
+
+    def test_cover(self):
+        """ IP Table Cover """
+
+        # add a loop back with a /32 prefix
+        lo = VppLoInterface(self)
+        lo.admin_up()
+        a = VppIpInterfaceAddress(self, lo, "127.0.0.1", 32).add_vpp_config()
+
+        # add a neighbour that matches the loopback's /32
+        nbr = VppNeighbor(self,
+                          lo.sw_if_index,
+                          lo.remote_mac,
+                          "127.0.0.1").add_vpp_config()
+
+        # add the default route which will be the cover for /32
+        r = VppIpRoute(self, "0.0.0.0", 0,
+                       [VppRoutePath("127.0.0.1",
+                                     lo.sw_if_index)],
+                       register=False).add_vpp_config()
+
+        # add/remove/add a longer mask cover
+        r8 = VppIpRoute(self, "127.0.0.0", 8,
+                        [VppRoutePath("127.0.0.1",
+                                      lo.sw_if_index)]).add_vpp_config()
+        r8.remove_vpp_config()
+        r8.add_vpp_config()
+        r8.remove_vpp_config()
+
+        # remove the default route
+        r.remove_vpp_config()
+
+        # remove the interface prefix
+        a.remove_vpp_config()
+
+
+class TestIP4Replace(VppTestCase):
+    """ IPv4 Interface Address Replace """
+
+    @classmethod
+    def setUpClass(cls):
+        super(TestIP4Replace, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(TestIP4Replace, cls).tearDownClass()
+
+    def setUp(self):
+        super(TestIP4Replace, self).setUp()
+
+        self.create_pg_interfaces(range(4))
+
+        for i in self.pg_interfaces:
+            i.admin_up()
+
+    def tearDown(self):
+        super(TestIP4Replace, self).tearDown()
+        for i in self.pg_interfaces:
+            i.admin_down()
+
+    def get_n_pfxs(self, intf):
+        return len(self.vapi.ip_address_dump(intf.sw_if_index))
+
+    def test_replace(self):
+        """ IP interface address replace """
+
+        intf_pfxs = [[], [], [], []]
+
+        # add prefixes to each of the interfaces
+        for i in range(len(self.pg_interfaces)):
+            intf = self.pg_interfaces[i]
+
+            # 172.16.x.1/24
+            addr = "172.16.%d.1" % intf.sw_if_index
+            a = VppIpInterfaceAddress(self, intf, addr, 24).add_vpp_config()
+            intf_pfxs[i].append(a)
+
+            # 172.16.x.2/24 - a different address in the same subnet as above
+            addr = "172.16.%d.2" % intf.sw_if_index
+            a = VppIpInterfaceAddress(self, intf, addr, 24).add_vpp_config()
+            intf_pfxs[i].append(a)
+
+            # 172.15.x.2/24 - a different address and subnet
+            addr = "172.15.%d.2" % intf.sw_if_index
+            a = VppIpInterfaceAddress(self, intf, addr, 24).add_vpp_config()
+            intf_pfxs[i].append(a)
+
+        # a dump should n_address in it
+        for intf in self.pg_interfaces:
+            self.assertEqual(self.get_n_pfxs(intf), 3)
+
+        #
+        # remove all the address thru a replace
+        #
+        self.vapi.sw_interface_address_replace_begin()
+        self.vapi.sw_interface_address_replace_end()
+        for intf in self.pg_interfaces:
+            self.assertEqual(self.get_n_pfxs(intf), 0)
+
+        #
+        # add all the interface addresses back
+        #
+        for p in intf_pfxs:
+            for v in p:
+                v.add_vpp_config()
+        for intf in self.pg_interfaces:
+            self.assertEqual(self.get_n_pfxs(intf), 3)
+
+        #
+        # replace again, but this time update/re-add the address on the first
+        # two interfaces
+        #
+        self.vapi.sw_interface_address_replace_begin()
+
+        for p in intf_pfxs[:2]:
+            for v in p:
+                v.add_vpp_config()
+
+        self.vapi.sw_interface_address_replace_end()
+
+        # on the first two the address still exist,
+        # on the other two they do not
+        for intf in self.pg_interfaces[:2]:
+            self.assertEqual(self.get_n_pfxs(intf), 3)
+        for p in intf_pfxs[:2]:
+            for v in p:
+                self.assertTrue(v.query_vpp_config())
+        for intf in self.pg_interfaces[2:]:
+            self.assertEqual(self.get_n_pfxs(intf), 0)
+
+        #
+        # add all the interface addresses back on the last two
+        #
+        for p in intf_pfxs[2:]:
+            for v in p:
+                v.add_vpp_config()
+        for intf in self.pg_interfaces:
+            self.assertEqual(self.get_n_pfxs(intf), 3)
+
+        #
+        # replace again, this time add different prefixes on all the interfaces
+        #
+        self.vapi.sw_interface_address_replace_begin()
+
+        pfxs = []
+        for intf in self.pg_interfaces:
+            # 172.18.x.1/24
+            addr = "172.18.%d.1" % intf.sw_if_index
+            pfxs.append(VppIpInterfaceAddress(self, intf, addr,
+                                              24).add_vpp_config())
+
+        self.vapi.sw_interface_address_replace_end()
+
+        # only .18 should exist on each interface
+        for intf in self.pg_interfaces:
+            self.assertEqual(self.get_n_pfxs(intf), 1)
+        for pfx in pfxs:
+            self.assertTrue(pfx.query_vpp_config())
+
+        #
+        # remove everything
+        #
+        self.vapi.sw_interface_address_replace_begin()
+        self.vapi.sw_interface_address_replace_end()
+        for intf in self.pg_interfaces:
+            self.assertEqual(self.get_n_pfxs(intf), 0)
+
+        #
+        # add prefixes to each interface. post-begin add the prefix from
+        # interface X onto interface Y. this would normally be an error
+        # since it would generate a 'duplicate address' warning. but in
+        # this case, since what is newly downloaded is sane, it's ok
+        #
+        for intf in self.pg_interfaces:
+            # 172.18.x.1/24
+            addr = "172.18.%d.1" % intf.sw_if_index
+            VppIpInterfaceAddress(self, intf, addr, 24).add_vpp_config()
+
+        self.vapi.sw_interface_address_replace_begin()
+
+        pfxs = []
+        for intf in self.pg_interfaces:
+            # 172.18.x.1/24
+            addr = "172.18.%d.1" % (intf.sw_if_index + 1)
+            pfxs.append(VppIpInterfaceAddress(self, intf,
+                                              addr, 24).add_vpp_config())
+
+        self.vapi.sw_interface_address_replace_end()
+
+        self.logger.info(self.vapi.cli("sh int addr"))
+
+        for intf in self.pg_interfaces:
+            self.assertEqual(self.get_n_pfxs(intf), 1)
+        for pfx in pfxs:
+            self.assertTrue(pfx.query_vpp_config())
+
+
 if __name__ == '__main__':
     unittest.main(testRunner=VppTestRunner)