Proxy ND (RFC4389 - or a sub-set thereof). This allows the 'emulation' of bridging. That is hosts in one sub-net reachable via differenet interfaces.

Introducate a new API command:
  ip6 nd proxy <host-address> <interface>

this indicates 2 things;
 1) that host <host-address> is reachable out of interface <interface>. VPP will thus install that route.
 2) NS requests sent to <host-address> will be responeded to (i.e. proxied).

Change-Id: I863f967fdb5097ab3b574769c70afdbfc8d5478a
Signed-off-by: Neale Ranns <nranns@cisco.com>

2 files changed, 282 insertions, 17 deletions

diff --git a/test/test_ip6.py b/test/test_ip6.py
index b8278329..070e2d7d 100644
--- a/test/test_ip6.py
+++ b/test/test_ip6.py
@@ -1,17 +1,20 @@
 #!/usr/bin/env python
 
 import unittest
-import socket
+from socket import AF_INET6
 
 from framework import VppTestCase, VppTestRunner
 from vpp_sub_interface import VppSubInterface, VppDot1QSubint
 from vpp_pg_interface import is_ipv6_misc
+from vpp_neighbor import find_nbr
 
 from scapy.packet import Raw
 from scapy.layers.l2 import Ether, Dot1Q
 from scapy.layers.inet6 import IPv6, UDP, ICMPv6ND_NS, ICMPv6ND_RS, \
     ICMPv6ND_RA, ICMPv6NDOptSrcLLAddr, getmacbyip6, ICMPv6MRD_Solicitation, \
-    ICMPv6NDOptMTU, ICMPv6NDOptSrcLLAddr, ICMPv6NDOptPrefixInfo
+    ICMPv6NDOptMTU, ICMPv6NDOptSrcLLAddr, ICMPv6NDOptPrefixInfo, \
+    ICMPv6ND_NA, ICMPv6NDOptDstLLAddr
+
 from util import ppp
 from scapy.utils6 import in6_getnsma, in6_getnsmac, in6_ptop, in6_islladdr, \
     in6_mactoifaceid, in6_ismaddr
@@ -24,7 +27,71 @@ def mk_ll_addr(mac):
     return addr
 
 
-class TestIPv6(VppTestCase):
+class TestIPv6ND(VppTestCase):
+    def validate_ra(self, intf, rx, dst_ip=None):
+        if not dst_ip:
+            dst_ip = intf.remote_ip6
+
+        # unicasted packets must come to the unicast mac
+        self.assertEqual(rx[Ether].dst, intf.remote_mac)
+
+        # and from the router's MAC
+        self.assertEqual(rx[Ether].src, intf.local_mac)
+
+        # the rx'd RA should be addressed to the sender's source
+        self.assertTrue(rx.haslayer(ICMPv6ND_RA))
+        self.assertEqual(in6_ptop(rx[IPv6].dst),
+                         in6_ptop(dst_ip))
+
+        # and come from the router's link local
+        self.assertTrue(in6_islladdr(rx[IPv6].src))
+        self.assertEqual(in6_ptop(rx[IPv6].src),
+                         in6_ptop(mk_ll_addr(intf.local_mac)))
+
+    def validate_na(self, intf, rx, dst_ip=None, tgt_ip=None):
+        if not dst_ip:
+            dst_ip = intf.remote_ip6
+        if not tgt_ip:
+            dst_ip = intf.local_ip6
+
+        # unicasted packets must come to the unicast mac
+        self.assertEqual(rx[Ether].dst, intf.remote_mac)
+
+        # and from the router's MAC
+        self.assertEqual(rx[Ether].src, intf.local_mac)
+
+        # the rx'd NA should be addressed to the sender's source
+        self.assertTrue(rx.haslayer(ICMPv6ND_NA))
+        self.assertEqual(in6_ptop(rx[IPv6].dst),
+                         in6_ptop(dst_ip))
+
+        # and come from the target address
+        self.assertEqual(in6_ptop(rx[IPv6].src), in6_ptop(tgt_ip))
+
+        # Dest link-layer options should have the router's MAC
+        dll = rx[ICMPv6NDOptDstLLAddr]
+        self.assertEqual(dll.lladdr, intf.local_mac)
+
+    def send_and_expect_ra(self, intf, pkts, remark, dst_ip=None,
+                           filter_out_fn=is_ipv6_misc):
+        intf.add_stream(pkts)
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = intf.get_capture(1, filter_out_fn=filter_out_fn)
+
+        self.assertEqual(len(rx), 1)
+        rx = rx[0]
+        self.validate_ra(intf, rx, dst_ip)
+
+    def send_and_assert_no_replies(self, intf, pkts, remark):
+        intf.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        intf.assert_nothing_captured(remark=remark)
+
+
+class TestIPv6(TestIPv6ND):
     """ IPv6 Test Case """
 
     @classmethod
@@ -112,7 +179,7 @@ class TestIPv6(VppTestCase):
         n_int = len(self.interfaces)
         percent = 0
         counter = 0.0
-        dest_addr = socket.inet_pton(socket.AF_INET6, "fd02::1")
+        dest_addr = inet_pton(AF_INET6, "fd02::1")
         dest_addr_len = 128
         for i in self.interfaces:
             next_hop_address = i.local_ip6n
@@ -225,12 +292,6 @@ class TestIPv6(VppTestCase):
             pkts = i.parent.get_capture()
             self.verify_capture(i, pkts)
 
-    def send_and_assert_no_replies(self, intf, pkts, remark):
-        intf.add_stream(pkts)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
-        intf.assert_nothing_captured(remark=remark)
-
     def test_ns(self):
         """ IPv6 Neighbour Solicitation Exceptions
 
@@ -243,8 +304,8 @@ class TestIPv6(VppTestCase):
         #
         # An NS from a non link source address
         #
-        nsma = in6_getnsma(inet_pton(socket.AF_INET6, self.pg0.local_ip6))
-        d = inet_ntop(socket.AF_INET6, nsma)
+        nsma = in6_getnsma(inet_pton(AF_INET6, self.pg0.local_ip6))
+        d = inet_ntop(AF_INET6, nsma)
 
         p = (Ether(dst=in6_getnsmac(nsma)) /
              IPv6(dst=d, src="2002::2") /
@@ -261,8 +322,8 @@ class TestIPv6(VppTestCase):
         # not a member of FAILS
         #
         if 0:
-            nsma = in6_getnsma(inet_pton(socket.AF_INET6, "fd::ffff"))
-            d = inet_ntop(socket.AF_INET6, nsma)
+            nsma = in6_getnsma(inet_pton(AF_INET6, "fd::ffff"))
+            d = inet_ntop(AF_INET6, nsma)
 
             p = (Ether(dst=in6_getnsmac(nsma)) /
                  IPv6(dst=d, src=self.pg0.remote_ip6) /
@@ -277,8 +338,8 @@ class TestIPv6(VppTestCase):
         #
         # An NS whose target address is one the router does not own
         #
-        nsma = in6_getnsma(inet_pton(socket.AF_INET6, self.pg0.local_ip6))
-        d = inet_ntop(socket.AF_INET6, nsma)
+        nsma = in6_getnsma(inet_pton(AF_INET6, self.pg0.local_ip6))
+        d = inet_ntop(AF_INET6, nsma)
 
         p = (Ether(dst=in6_getnsmac(nsma)) /
              IPv6(dst=d, src=self.pg0.remote_ip6) /
@@ -418,7 +479,7 @@ class TestIPv6(VppTestCase):
         # Send the RS multicast
         #
         self.pg0.ip6_ra_config(send_unicast=1)
-        dmac = in6_getnsmac(inet_pton(socket.AF_INET6, "ff02::2"))
+        dmac = in6_getnsmac(inet_pton(AF_INET6, "ff02::2"))
         ll = mk_ll_addr(self.pg0.remote_mac)
         p = (Ether(dst=dmac, src=self.pg0.remote_mac) /
              IPv6(dst="ff02::2", src=ll) /
@@ -629,5 +690,203 @@ class TestIPv6(VppTestCase):
         #
         self.pg0.ip6_ra_config(no=1, suppress=1, send_unicast=0)
 
+
+class IPv6NDProxyTest(TestIPv6ND):
+    """ IPv6 ND ProxyTest Case """
+
+    def setUp(self):
+        super(IPv6NDProxyTest, self).setUp()
+
+        # create 3 pg interfaces
+        self.create_pg_interfaces(range(3))
+
+        # pg0 is the master interface, with the configured subnet
+        self.pg0.admin_up()
+        self.pg0.config_ip6()
+        self.pg0.resolve_ndp()
+
+        self.pg1.ip6_enable()
+        self.pg2.ip6_enable()
+
+    def tearDown(self):
+        super(IPv6NDProxyTest, self).tearDown()
+
+    def test_nd_proxy(self):
+        """ IPv6 Proxy ND """
+
+        #
+        # Generate some hosts in the subnet that we are proxying
+        #
+        self.pg0.generate_remote_hosts(8)
+
+        nsma = in6_getnsma(inet_pton(AF_INET6, self.pg0.local_ip6))
+        d = inet_ntop(AF_INET6, nsma)
+
+        #
+        # Send an NS for one of those remote hosts on one of the proxy links
+        # expect no response since it's from an address that is not
+        # on the link that has the prefix configured
+        #
+        ns_pg1 = (Ether(dst=in6_getnsmac(nsma), src=self.pg1.remote_mac) /
+                  IPv6(dst=d, src=self.pg0._remote_hosts[2].ip6) /
+                  ICMPv6ND_NS(tgt=self.pg0.local_ip6) /
+                  ICMPv6NDOptSrcLLAddr(lladdr=self.pg0._remote_hosts[2].mac))
+
+        self.send_and_assert_no_replies(self.pg1, ns_pg1, "Off link NS")
+
+        #
+        # Add proxy support for the host
+        #
+        self.vapi.ip6_nd_proxy(
+            inet_pton(AF_INET6, self.pg0._remote_hosts[2].ip6),
+            self.pg1.sw_if_index)
+
+        #
+        # try that NS again. this time we expect an NA back
+        #
+        self.pg1.add_stream(ns_pg1)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg1.get_capture(1)
+
+        self.validate_na(self.pg1, rx[0],
+                         dst_ip=self.pg0._remote_hosts[2].ip6,
+                         tgt_ip=self.pg0.local_ip6)
+
+        #
+        # ... and that we have an entry in the ND cache
+        #
+        self.assertTrue(find_nbr(self,
+                                 self.pg1.sw_if_index,
+                                 self.pg0._remote_hosts[2].ip6,
+                                 inet=AF_INET6))
+
+        #
+        # ... and we can route traffic to it
+        #
+        t = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
+             IPv6(dst=self.pg0._remote_hosts[2].ip6,
+                  src=self.pg0.remote_ip6) /
+             UDP(sport=10000, dport=20000) /
+             Raw('\xa5' * 100))
+
+        self.pg0.add_stream(t)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg1.get_capture(1)
+        rx = rx[0]
+
+        self.assertEqual(rx[Ether].dst, self.pg0._remote_hosts[2].mac)
+        self.assertEqual(rx[Ether].src, self.pg1.local_mac)
+
+        self.assertEqual(rx[IPv6].src, t[IPv6].src)
+        self.assertEqual(rx[IPv6].dst, t[IPv6].dst)
+
+        #
+        # Test we proxy for the host on the main interface
+        #
+        ns_pg0 = (Ether(dst=in6_getnsmac(nsma), src=self.pg0.remote_mac) /
+                  IPv6(dst=d, src=self.pg0.remote_ip6) /
+                  ICMPv6ND_NS(tgt=self.pg0._remote_hosts[2].ip6) /
+                  ICMPv6NDOptSrcLLAddr(lladdr=self.pg0.remote_mac))
+
+        self.pg0.add_stream(ns_pg0)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg0.get_capture(1)
+
+        self.validate_na(self.pg0, rx[0],
+                         tgt_ip=self.pg0._remote_hosts[2].ip6,
+                         dst_ip=self.pg0.remote_ip6)
+
+        #
+        # Setup and resolve proxy for another host on another interface
+        #
+        ns_pg2 = (Ether(dst=in6_getnsmac(nsma), src=self.pg2.remote_mac) /
+                  IPv6(dst=d, src=self.pg0._remote_hosts[3].ip6) /
+                  ICMPv6ND_NS(tgt=self.pg0.local_ip6) /
+                  ICMPv6NDOptSrcLLAddr(lladdr=self.pg0._remote_hosts[2].mac))
+
+        self.vapi.ip6_nd_proxy(
+            inet_pton(AF_INET6, self.pg0._remote_hosts[3].ip6),
+            self.pg2.sw_if_index)
+
+        self.pg2.add_stream(ns_pg2)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg2.get_capture(1)
+
+        self.validate_na(self.pg2, rx[0],
+                         dst_ip=self.pg0._remote_hosts[3].ip6,
+                         tgt_ip=self.pg0.local_ip6)
+
+        self.assertTrue(find_nbr(self,
+                                 self.pg2.sw_if_index,
+                                 self.pg0._remote_hosts[3].ip6,
+                                 inet=AF_INET6))
+
+        #
+        # hosts can communicate. pg2->pg1
+        #
+        t2 = (Ether(dst=self.pg2.local_mac,
+                    src=self.pg0.remote_hosts[3].mac) /
+              IPv6(dst=self.pg0._remote_hosts[2].ip6,
+                   src=self.pg0._remote_hosts[3].ip6) /
+              UDP(sport=10000, dport=20000) /
+              Raw('\xa5' * 100))
+
+        self.pg2.add_stream(t2)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg1.get_capture(1)
+        rx = rx[0]
+
+        self.assertEqual(rx[Ether].dst, self.pg0._remote_hosts[2].mac)
+        self.assertEqual(rx[Ether].src, self.pg1.local_mac)
+
+        self.assertEqual(rx[IPv6].src, t2[IPv6].src)
+        self.assertEqual(rx[IPv6].dst, t2[IPv6].dst)
+
+        #
+        # remove the proxy configs
+        #
+        self.vapi.ip6_nd_proxy(
+            inet_pton(AF_INET6, self.pg0._remote_hosts[2].ip6),
+            self.pg1.sw_if_index,
+            is_del=1)
+        self.vapi.ip6_nd_proxy(
+            inet_pton(AF_INET6, self.pg0._remote_hosts[3].ip6),
+            self.pg2.sw_if_index,
+            is_del=1)
+
+        self.assertFalse(find_nbr(self,
+                                  self.pg2.sw_if_index,
+                                  self.pg0._remote_hosts[3].ip6,
+                                  inet=AF_INET6))
+        self.assertFalse(find_nbr(self,
+                                  self.pg1.sw_if_index,
+                                  self.pg0._remote_hosts[2].ip6,
+                                  inet=AF_INET6))
+
+        #
+        # no longer proxy-ing...
+        #
+        self.send_and_assert_no_replies(self.pg0, ns_pg0, "Proxy unconfigured")
+        self.send_and_assert_no_replies(self.pg1, ns_pg1, "Proxy unconfigured")
+        self.send_and_assert_no_replies(self.pg2, ns_pg2, "Proxy unconfigured")
+
+        #
+        # no longer forwarding. traffic generates NS out of the glean/main
+        # interface
+        #
+        self.pg2.add_stream(t2)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        rx = self.pg0.get_capture(1)
+
+        self.assertTrue(rx[0].haslayer(ICMPv6ND_NS))
+
+
 if __name__ == '__main__':
     unittest.main(testRunner=VppTestRunner)
diff --git a/test/vpp_papi_provider.py b/test/vpp_papi_provider.py
index b9c4d0c1..f04537bf 100644
--- a/test/vpp_papi_provider.py
+++ b/test/vpp_papi_provider.py
@@ -276,6 +276,12 @@ class VppPapiProvider(object):
                         {'sw_if_index': sw_if_index,
                          'suppress': suppress})
 
+    def ip6_nd_proxy(self, address, sw_if_index, is_del=0):
+        return self.api(self.papi.ip6nd_proxy_add_del,
+                        {'address': address,
+                         'sw_if_index': sw_if_index,
+                         'is_del': is_del})
+
     def ip6_sw_interface_ra_config(self, sw_if_index,
                                    no,
                                    suppress,