fib: MPLS EOS chains built for attached prefixes should link to a lookup DPO

Type: fix

Presently a local label associated with an attached or connected prefix will link to the glean. This is a problem since it will never use the adj-fibs that are installed for that attached prefix. Instead link the local label to a lookup in the table in which the attached link is bound.

Signed-off-by: Neale Ranns <neale@graphiant.com>
Change-Id: Iad49fb6168b9ba47216a9a52bd262363b49c3c43
diff --git a/test/test_mpls.py b/test/test_mpls.py
index 2b959e4..34645a9 100644
--- a/test/test_mpls.py
+++ b/test/test_mpls.py
@@ -1563,6 +1563,33 @@
                                           VppMplsLabel(32),
                                           VppMplsLabel(99)])
 
+    def test_attached(self):
+        """ Attach Routes with Local Label """
+
+        #
+        # test that if a local label is associated with an attached/connected
+        # prefix, that we can reach hosts in the prefix.
+        #
+        binding = VppMplsIpBind(self, 44,
+                                self.pg0._local_ip4_subnet,
+                                self.pg0.local_ip4_prefix_len)
+        binding.add_vpp_config()
+
+        tx = (Ether(src=self.pg1.remote_mac,
+                    dst=self.pg1.local_mac) /
+              MPLS(label=44, ttl=64) /
+              IP(src=self.pg0.remote_ip4, dst=self.pg0.remote_ip4) /
+              UDP(sport=1234, dport=1234) /
+              Raw(b'\xa5' * 100))
+        rxs = self.send_and_expect(self.pg0, [tx], self.pg0)
+        for rx in rxs:
+            # if there's an ARP then the label is linked to the glean
+            # which is wrong.
+            self.assertFalse(rx.haslayer(ARP))
+            # it should be unicasted to the host
+            self.assertEqual(rx[Ether].dst, self.pg0.remote_mac)
+            self.assertEqual(rx[IP].dst, self.pg0.remote_ip4)
+
 
 class TestMPLSDisabled(VppTestCase):
     """ MPLS disabled """