IP route local and connected

allow routes that are local and connected to be added via the API.
this emulates the addition of a second address in the same subnet
added to an interface.

Change-Id: Ib18a08c26956be9a07b3360664210c8cf6734c84
Signed-off-by: Neale Ranns <nranns@cisco.com>
(cherry picked from commit 7425f9289bdc17d330044b0df0fc31cdeeca626b)

4 files changed, 51 insertions, 7 deletions

diff --git a/src/vnet/ethernet/arp.c b/src/vnet/ethernet/arp.c
index 13b718d4c62..e6e3a515b97 100644
--- a/src/vnet/ethernet/arp.c
+++ b/src/vnet/ethernet/arp.c
@@ -894,6 +894,7 @@ typedef enum
   _ (gratuitous_arp, "ARP probe or announcement dropped") \
   _ (interface_no_table, "Interface is not mapped to an IP table") \
   _ (interface_not_ip_enabled, "Interface is not IP enabled") \
+  _ (unnumbered_mismatch, "RX interface is unnumbered to different subnet") \
 
 typedef enum
 {
@@ -1258,7 +1259,10 @@ arp_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
 	      if (is_unnum0)
 		{
 		  if (!arp_unnumbered (p0, sw_if_index0, conn_sw_if_index0))
-		    goto drop2;
+		    {
+		      error0 = ETHERNET_ARP_ERROR_unnumbered_mismatch;
+		      goto drop2;
+		    }
 		}
 	    }
 
diff --git a/src/vnet/ip/ip_api.c b/src/vnet/ip/ip_api.c
index 42ce883c234..b9fa001553f 100644
--- a/src/vnet/ip/ip_api.c
+++ b/src/vnet/ip/ip_api.c
@@ -808,7 +808,13 @@ add_del_route_t_handler (u8 is_multipath,
       path.frp_eos = MPLS_NON_EOS;
     }
   if (is_local)
-    path_flags |= FIB_ROUTE_PATH_LOCAL;
+    {
+      path_flags |= FIB_ROUTE_PATH_LOCAL;
+      if (~0 != next_hop_sw_if_index)
+	{
+	  entry_flags |= (FIB_ENTRY_FLAG_CONNECTED | FIB_ENTRY_FLAG_LOCAL);
+	}
+    }
   if (is_dvr)
     path_flags |= FIB_ROUTE_PATH_DVR;
   if (is_resolve_host)
@@ -838,7 +844,8 @@ add_del_route_t_handler (u8 is_multipath,
 
   stats_dslock_with_hint (1 /* release hint */ , 2 /* tag */ );
 
-  if (is_drop || is_local || is_classify || is_unreach || is_prohibit)
+  if (is_drop || (is_local && (~0 == next_hop_sw_if_index)) ||
+      is_classify || is_unreach || is_prohibit)
     {
       /*
        * special route types that link directly to the adj
diff --git a/test/test_neighbor.py b/test/test_neighbor.py
index d551c94584a..47f002cd91a 100644
--- a/test/test_neighbor.py
+++ b/test/test_neighbor.py
@@ -1380,6 +1380,40 @@ class ARPTestCase(VppTestCase):
         #
         self.assertLess(len(rx), 64)
 
+    def test_arp_forus(self):
+        """ ARP for for-us """
+
+        #
+        # Test that VPP responds with ARP requests to addresses that
+        # are connected and local routes.
+        # Use one of the 'remote' addresses in the subnet as a local address
+        # The intention of this route is that it then acts like a secondardy
+        # address added to an interface
+        #
+        self.pg0.generate_remote_hosts(2)
+
+        forus = VppIpRoute(self, self.pg0.remote_hosts[1].ip4, 32,
+                           [VppRoutePath(self.pg0.remote_hosts[1].ip4,
+                                         self.pg0.sw_if_index)],
+                           is_local=1)
+        forus.add_vpp_config()
+
+        p = (Ether(dst="ff:ff:ff:ff:ff:ff",
+                   src=self.pg0.remote_mac) /
+             ARP(op="who-has",
+                 hwdst=self.pg0.local_mac,
+                 hwsrc=self.pg0.remote_mac,
+                 pdst=self.pg0.remote_hosts[1].ip4,
+                 psrc=self.pg0.remote_ip4))
+
+        rx = self.send_and_expect(self.pg0, [p], self.pg0)
+
+        self.verify_arp_resp(rx[0],
+                             self.pg0.local_mac,
+                             self.pg0.remote_mac,
+                             self.pg0.remote_hosts[1].ip4,
+                             self.pg0.remote_ip4)
+
 
 class NeighborStatsTestCase(VppTestCase):
     """ ARP Test Case """
diff --git a/test/vpp_ip_route.py b/test/vpp_ip_route.py
index 5a6598eb012..d024f10c5e7 100644
--- a/test/vpp_ip_route.py
+++ b/test/vpp_ip_route.py
@@ -391,8 +391,7 @@ class VppIpRoute(VppObject):
         self.is_prohibit = is_prohibit
 
     def add_vpp_config(self):
-        if self.is_local or self.is_unreach or \
-           self.is_prohibit or self.is_drop:
+        if self.is_unreach or self.is_prohibit or self.is_drop:
             r = self._test.vapi.ip_add_del_route(
                 self.dest_addr,
                 self.dest_addr_len,
@@ -421,6 +420,7 @@ class VppIpRoute(VppObject):
                     next_hop_id=path.next_hop_id,
                     is_ipv6=self.is_ip6,
                     is_dvr=path.is_dvr,
+                    is_local=self.is_local,
                     is_resolve_host=path.is_resolve_host,
                     is_resolve_attached=path.is_resolve_attached,
                     is_source_lookup=path.is_source_lookup,
@@ -430,8 +430,7 @@ class VppIpRoute(VppObject):
         self._test.registry.register(self, self._test.logger)
 
     def remove_vpp_config(self):
-        if self.is_local or self.is_unreach or \
-           self.is_prohibit or self.is_drop:
+        if self.is_unreach or self.is_prohibit or self.is_drop:
             self._test.vapi.ip_add_del_route(
                 self.dest_addr,
                 self.dest_addr_len,