Ping response in a VRF context uses correct FIB for response

Change-Id: I3b626a1fb9d74ebc609ded14c16c5e3d5a1655ab
Signed-off-by: Neale Ranns <nranns@cisco.com>

4 files changed, 92 insertions, 11 deletions

diff --git a/test/test_mpls.py b/test/test_mpls.py
index e6a1e8c57d0..24fc4129ecd 100644
--- a/test/test_mpls.py
+++ b/test/test_mpls.py
@@ -8,7 +8,7 @@ from vpp_ip_route import IpRoute, RoutePath, MplsRoute, MplsIpBind
 
 from scapy.packet import Raw
 from scapy.layers.l2 import Ether
-from scapy.layers.inet import IP, UDP
+from scapy.layers.inet import IP, UDP, ICMP
 from scapy.layers.inet6 import IPv6
 from scapy.contrib.mpls import MPLS
 from util import ppp
@@ -46,7 +46,7 @@ class TestMPLS(VppTestCase):
         super(TestMPLS, self).tearDown()
 
     # the default of 64 matches the IP packet TTL default
-    def create_stream_labelled_ip4(self, src_if, mpls_labels, mpls_ttl=255):
+    def create_stream_labelled_ip4(self, src_if, mpls_labels, mpls_ttl=255, ping=0, ip_itf=None):
         pkts = []
         for i in range(0, 257):
             info = self.create_packet_info(src_if.sw_if_index,
@@ -59,9 +59,15 @@ class TestMPLS(VppTestCase):
                     p = p / MPLS(label=mpls_labels[ii], ttl=mpls_ttl, s=1)
                 else:
                     p = p / MPLS(label=mpls_labels[ii], ttl=mpls_ttl, s=0)
-            p = (p / IP(src=src_if.remote_ip4, dst=src_if.remote_ip4) /
-                 UDP(sport=1234, dport=1234) /
-                 Raw(payload))
+            if not ping:
+                p = (p / IP(src=src_if.local_ip4, dst=src_if.remote_ip4) / 
+                     UDP(sport=1234, dport=1234) /
+                     Raw(payload))
+            else:
+                p = (p / IP(src=ip_itf.remote_ip4,
+                            dst=ip_itf.local_ip4) /
+                     ICMP())
+
             info.data = p.copy()
             pkts.append(p)
         return pkts
@@ -104,7 +110,7 @@ class TestMPLS(VppTestCase):
                     capture.remove(p)
         return capture
 
-    def verify_capture_ip4(self, src_if, capture, sent):
+    def verify_capture_ip4(self, src_if, capture, sent, ping_resp=0):
         try:
             capture = self.verify_filter(capture, sent)
 
@@ -121,10 +127,14 @@ class TestMPLS(VppTestCase):
                 tx_ip = tx[IP]
                 rx_ip = rx[IP]
 
-                self.assertEqual(rx_ip.src, tx_ip.src)
-                self.assertEqual(rx_ip.dst, tx_ip.dst)
-                # IP processing post pop has decremented the TTL
-                self.assertEqual(rx_ip.ttl + 1, tx_ip.ttl)
+                if not ping_resp:
+                    self.assertEqual(rx_ip.src, tx_ip.src)
+                    self.assertEqual(rx_ip.dst, tx_ip.dst)
+                    # IP processing post pop has decremented the TTL
+                    self.assertEqual(rx_ip.ttl + 1, tx_ip.ttl)
+                else:
+                    self.assertEqual(rx_ip.src, tx_ip.dst)
+                    self.assertEqual(rx_ip.dst, tx_ip.src)
 
         except:
             raise
@@ -692,6 +702,59 @@ class TestMPLS(VppTestCase):
         rx = self.pg1.get_capture()
         self.verify_capture_ip6(self.pg0, rx, tx)
 
+    def test_deag(self):
+        """ MPLS Deagg """
+
+        #
+        # A de-agg route - next-hop lookup in default table
+        #
+        route_34_eos = MplsRoute(self, 34, 1,
+                                  [RoutePath("0.0.0.0",
+                                             0xffffffff,
+                                             nh_table_id=0)])
+        route_34_eos.add_vpp_config()
+
+        #
+        # ping an interface in the default table
+        # PG0 is in the default table
+        #
+        self.vapi.cli("clear trace")
+        tx = self.create_stream_labelled_ip4(self.pg0, [34], ping=1,
+                                             ip_itf=self.pg0)
+        self.pg0.add_stream(tx)
+
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        rx = self.pg0.get_capture()
+        self.verify_capture_ip4(self.pg0, rx, tx, ping_resp=1)
+
+        #
+        # A de-agg route - next-hop lookup in non-default table
+        #
+        route_35_eos = MplsRoute(self, 35, 1,
+                                  [RoutePath("0.0.0.0",
+                                             0xffffffff,
+                                             nh_table_id=1)])
+        route_35_eos.add_vpp_config()
+
+        #
+        # ping an interface in the non-default table
+        # PG0 is in the default table. packet arrive labelled in the
+        # default table and egress unlabelled in the non-default
+        #
+        self.vapi.cli("clear trace")
+        tx = self.create_stream_labelled_ip4(self.pg0, [35], ping=1, ip_itf=self.pg1)
+        self.pg0.add_stream(tx)
+
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        rx = self.pg1.get_capture()
+        self.verify_capture_ip4(self.pg1, rx, tx, ping_resp=1)
+
+        route_35_eos.remove_vpp_config()
+        route_34_eos.remove_vpp_config()
 
 if __name__ == '__main__':
     unittest.main(testRunner=VppTestRunner)
diff --git a/test/vpp_ip_route.py b/test/vpp_ip_route.py
index 1dc8c1abb0f..75f400f1dc0 100644
--- a/test/vpp_ip_route.py
+++ b/test/vpp_ip_route.py
@@ -102,7 +102,8 @@ class MplsRoute:
                                                next_hop_out_label_stack=path.nh_labels,
                                                next_hop_n_out_labels=len(
                                                    path.nh_labels),
-                                               next_hop_via_label=path.nh_via_label)
+                                               next_hop_via_label=path.nh_via_label,
+                                               next_hop_table_id=path.nh_table_id)
 
     def remove_vpp_config(self):
         for path in self.paths:
diff --git a/vnet/vnet/dpo/lookup_dpo.c b/vnet/vnet/dpo/lookup_dpo.c
index e5043663960..96fedd27ce9 100644
--- a/vnet/vnet/dpo/lookup_dpo.c
+++ b/vnet/vnet/dpo/lookup_dpo.c
@@ -385,6 +385,9 @@ lookup_dpo_ip4_inline (vlib_main_t * vm,
 	    lb0 = load_balance_get(lbi0);
 	    lb1 = load_balance_get(lbi1);
 
+            vnet_buffer(b0)->sw_if_index[VLIB_TX] = fib_index0;
+            vnet_buffer(b1)->sw_if_index[VLIB_TX] = fib_index1;
+
 	    /* Use flow hash to compute multipath adjacency. */
 	    hash_c0 = vnet_buffer (b0)->ip.flow_hash = 0;
 	    hash_c1 = vnet_buffer (b1)->ip.flow_hash = 0;
@@ -500,6 +503,8 @@ lookup_dpo_ip4_inline (vlib_main_t * vm,
 	    ip4_src_fib_lookup_one (fib_index0, input_addr, &lbi0);
 	    lb0 = load_balance_get(lbi0);
 
+            vnet_buffer(b0)->sw_if_index[VLIB_TX] = fib_index0;
+
 	    /* Use flow hash to compute multipath adjacency. */
 	    hash_c0 = vnet_buffer (b0)->ip.flow_hash = 0;
 
@@ -722,6 +727,9 @@ lookup_dpo_ip6_inline (vlib_main_t * vm,
 	    lb0 = load_balance_get(lbi0);
 	    lb1 = load_balance_get(lbi1);
 
+            vnet_buffer(b0)->sw_if_index[VLIB_TX] = fib_index0;
+            vnet_buffer(b1)->sw_if_index[VLIB_TX] = fib_index1;
+
 	    /* Use flow hash to compute multipath adjacency. */
 	    hash_c0 = vnet_buffer (b0)->ip.flow_hash = 0;
 	    hash_c1 = vnet_buffer (b1)->ip.flow_hash = 0;
@@ -837,6 +845,8 @@ lookup_dpo_ip6_inline (vlib_main_t * vm,
 					       input_addr0);
 	    lb0 = load_balance_get(lbi0);
 
+            vnet_buffer(b0)->sw_if_index[VLIB_TX] = fib_index0;
+
 	    /* Use flow hash to compute multipath adjacency. */
 	    hash_c0 = vnet_buffer (b0)->ip.flow_hash = 0;
 
diff --git a/vnet/vnet/ip/ip4_forward.c b/vnet/vnet/ip/ip4_forward.c
index 6a9e066027c..6e91b9e91e1 100644
--- a/vnet/vnet/ip/ip4_forward.c
+++ b/vnet/vnet/ip/ip4_forward.c
@@ -1500,8 +1500,13 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
 
 	  fib_index0 = vec_elt (im->fib_index_by_sw_if_index,
 				vnet_buffer (p0)->sw_if_index[VLIB_RX]);
+	  fib_index0 = (vnet_buffer (p0)->sw_if_index[VLIB_TX] == (u32) ~ 0) ?
+	    fib_index0 : vnet_buffer (p0)->sw_if_index[VLIB_TX];
+
 	  fib_index1 = vec_elt (im->fib_index_by_sw_if_index,
 				vnet_buffer (p1)->sw_if_index[VLIB_RX]);
+	  fib_index1 = (vnet_buffer (p1)->sw_if_index[VLIB_TX] == (u32) ~ 0) ?
+	    fib_index1 : vnet_buffer (p1)->sw_if_index[VLIB_TX];
 
 	  mtrie0 = &ip4_fib_get (fib_index0)->mtrie;
 	  mtrie1 = &ip4_fib_get (fib_index1)->mtrie;
@@ -1721,6 +1726,8 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
 
 	  fib_index0 = vec_elt (im->fib_index_by_sw_if_index,
 				vnet_buffer (p0)->sw_if_index[VLIB_RX]);
+	  fib_index0 = (vnet_buffer (p0)->sw_if_index[VLIB_TX] == (u32) ~ 0) ?
+	    fib_index0 : vnet_buffer (p0)->sw_if_index[VLIB_TX];
 
 	  mtrie0 = &ip4_fib_get (fib_index0)->mtrie;