Support kube-proxy data plane

This plugin provides kube-proxy data plane on user space,
which is used to replace linux kernal's kube-proxy based on iptables.
The idea is largely inspired from VPP LB plugin.

Currently, kube-proxy plugin supports three service types:
1) Cluster IP plus Port: support any protocols, including TCP, UDP.
2) Node IP plus Node Port: currently only support UDP.
3) External Load Balancer.

Please refer to kp_plugin_doc.md for details.

Change-Id: I36690e417dd26ad5ec1bd77c7ea4b8100416cac6
Signed-off-by: Hongjun Ni <hongjun.ni@intel.com>
diff --git a/test/test_kubeproxy.py b/test/test_kubeproxy.py
new file mode 100644
index 0000000..418e03a
--- /dev/null
+++ b/test/test_kubeproxy.py
@@ -0,0 +1,203 @@
+import socket
+import unittest
+
+from scapy.layers.inet import IP, UDP
+from scapy.layers.inet6 import IPv6
+from scapy.layers.l2 import Ether
+from scapy.packet import Raw
+
+from framework import VppTestCase, running_extended_tests
+from util import ppp
+
+""" TestKP is a subclass of VPPTestCase classes.
+
+ TestKP class defines Four NAT test case for:
+  - IP4 to IP4 NAT
+  - IP4 to IP6 NAT
+  - IP6 to IP4 NAT
+  - IP6 to IP6 NAT
+
+"""
+
+
+class TestKP(VppTestCase):
+    """ Kube-proxy Test Case """
+
+    @classmethod
+    def setUpClass(cls):
+        super(TestKP, cls).setUpClass()
+        cls.pods = range(5)
+        cls.packets = range(5)
+
+        try:
+            cls.create_pg_interfaces(range(2))
+            cls.interfaces = list(cls.pg_interfaces)
+
+            for i in cls.interfaces:
+                i.admin_up()
+                i.config_ip4()
+                i.config_ip6()
+                i.disable_ipv6_ra()
+                i.resolve_arp()
+                i.resolve_ndp()
+            dst4 = socket.inet_pton(socket.AF_INET, "10.0.0.0")
+            dst6 = socket.inet_pton(socket.AF_INET6, "2002::")
+            cls.vapi.ip_add_del_route(dst4, 24, cls.pg1.remote_ip4n)
+            cls.vapi.ip_add_del_route(dst6, 16, cls.pg1.remote_ip6n, is_ipv6=1)
+        except Exception:
+            super(TestKP, cls).tearDownClass()
+            raise
+
+    def tearDown(self):
+        super(TestKP, self).tearDown()
+        if not self.vpp_dead:
+            self.logger.info(self.vapi.cli("show ku vip verbose"))
+
+    def getIPv4Flow(self, id):
+        return (IP(dst="90.0.%u.%u" % (id / 255, id % 255),
+                   src="40.0.%u.%u" % (id / 255, id % 255)) /
+                UDP(sport=10000 + id, dport=3306))
+
+    def getIPv6Flow(self, id):
+        return (IPv6(dst="2001::%u" % (id), src="fd00:f00d:ffff::%u" % (id)) /
+                UDP(sport=10000 + id, dport=3306))
+
+    def generatePackets(self, src_if, isv4):
+        self.reset_packet_infos()
+        pkts = []
+        for pktid in self.packets:
+            info = self.create_packet_info(src_if, self.pg1)
+            payload = self.info_to_payload(info)
+            ip = self.getIPv4Flow(pktid) if isv4 else self.getIPv6Flow(pktid)
+            packet = (Ether(dst=src_if.local_mac, src=src_if.remote_mac) /
+                      ip /
+                      Raw(payload))
+            self.extend_packet(packet, 128)
+            info.data = packet.copy()
+            pkts.append(packet)
+        return pkts
+
+    def checkInner(self, udp):
+        self.assertEqual(udp.dport, 3307)
+
+    def checkCapture(self, nat4, isv4):
+        self.pg0.assert_nothing_captured()
+        out = self.pg1.get_capture(len(self.packets))
+
+        load = [0] * len(self.pods)
+        self.info = None
+        for p in out:
+            try:
+                podid = 0
+                udp = None
+                if nat4:
+                    ip = p[IP]
+                    podid = int(ip.dst.split(".")[3])
+                    self.assertEqual(ip.version, 4)
+                    self.assertEqual(ip.flags, 0)
+                    self.assertEqual(ip.dst, "10.0.0.%u" % podid)
+                    self.assertEqual(ip.proto, 17)
+                    self.assertEqual(len(ip.options), 0)
+                    self.assertGreaterEqual(ip.ttl, 63)
+                    udp = p[UDP]
+                else:
+                    ip = p[IPv6]
+                    podid = ip.dst.split(":")
+                    podid = podid[len(podid) - 1]
+                    podid = 0 if podid == "" else int(podid)
+                    self.assertEqual(ip.version, 6)
+                    self.assertEqual(ip.tc, 0)
+                    self.assertEqual(ip.fl, 0)
+                    self.assertEqual(
+                        socket.inet_pton(socket.AF_INET6, ip.dst),
+                        socket.inet_pton(socket.AF_INET6, "2002::%u" % podid)
+                    )
+                    self.assertEqual(ip.nh, 17)
+                    self.assertGreaterEqual(ip.hlim, 63)
+                    udp = UDP(str(p[IPv6].payload))
+                    # self.assertEqual(len(ip.options), 0)
+                self.checkInner(udp)
+                load[podid] += 1
+            except:
+                self.logger.error(ppp("Unexpected or invalid packet:", p))
+                raise
+
+        # This is just to roughly check that the balancing algorithm
+        # is not completly biased.
+        for podid in self.pods:
+            if load[podid] < len(self.packets) / (len(self.pods) * 2):
+                self.log(
+                    "Pod isn't balanced: load[%d] = %d" % (podid, load[podid]))
+                raise Exception("Kube-proxy algorithm is biased")
+
+    def test_kp_ip4_nat4(self):
+        """ Kube-proxy NAT44 """
+        try:
+            self.vapi.cli("ku vip 90.0.0.0/8 port 3306 target_port 3307 nat4")
+            for podid in self.pods:
+                self.vapi.cli("ku pod 90.0.0.0/8 10.0.0.%u" % (podid))
+
+            self.pg0.add_stream(self.generatePackets(self.pg0, isv4=True))
+            self.pg_enable_capture(self.pg_interfaces)
+            self.pg_start()
+            self.checkCapture(nat4=True, isv4=True)
+
+        finally:
+            for podid in self.pods:
+                self.vapi.cli("ku pod 90.0.0.0/8 10.0.0.%u del" % (podid))
+            self.vapi.cli("ku vip 90.0.0.0/8 nat4 del")
+
+    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
+    def test_kp_ip6_nat4(self):
+        """ Kube-proxy NAT64 """
+
+        try:
+            self.vapi.cli("ku vip 90.0.0.0/8 port 3306 target_port 3307 nat4")
+            for podid in self.pods:
+                self.vapi.cli("ku pod 2001::/16 10.0.0.%u" % (podid))
+
+            self.pg0.add_stream(self.generatePackets(self.pg0, isv4=False))
+            self.pg_enable_capture(self.pg_interfaces)
+            self.pg_start()
+
+            self.checkCapture(nat4=True, isv4=False)
+        finally:
+            for podid in self.pods:
+                self.vapi.cli("ku pod 2001::/16 10.0.0.%u del" % (podid))
+            self.vapi.cli("ku vip 2001::/16 nat4 del")
+
+    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
+    def test_kp_ip4_nat6(self):
+        """ Kube-proxy NAT46 """
+        try:
+            self.vapi.cli("ku vip 90.0.0.0/8 port 3306 target_port 3307 nat6")
+            for podid in self.pods:
+                self.vapi.cli("ku pod 90.0.0.0/8 2002::%u" % (podid))
+
+            self.pg0.add_stream(self.generatePackets(self.pg0, isv4=True))
+            self.pg_enable_capture(self.pg_interfaces)
+            self.pg_start()
+
+            self.checkCapture(nat4=False, isv4=True)
+        finally:
+            for podid in self.pods:
+                self.vapi.cli("ku pod 90.0.0.0/8 2002::%u" % (podid))
+            self.vapi.cli("ku vip 90.0.0.0/8 nat6 del")
+
+    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
+    def test_kp_ip6_nat6(self):
+        """ Kube-proxy NAT66 """
+        try:
+            self.vapi.cli("ku vip 90.0.0.0/8 port 3306 target_port 3307 nat6")
+            for podid in self.pods:
+                self.vapi.cli("ku pod 2001::/16 2002::%u" % (podid))
+
+            self.pg0.add_stream(self.generatePackets(self.pg0, isv4=False))
+            self.pg_enable_capture(self.pg_interfaces)
+            self.pg_start()
+
+            self.checkCapture(nat4=False, isv4=False)
+        finally:
+            for podid in self.pods:
+                self.vapi.cli("ku pod 2001::/16 2002::%u del" % (podid))
+            self.vapi.cli("ku vip 2001::/16 nat6 del")