ip-neighbor: Handle local MAC address change for incomplete adjacencies

Type: fix

When the local MAC address of an interface changes the rewrite strings
of all adjacency types need to be updated - this patch fixes the missing
case of incomplete adjacencies.
I moved the update of all adj types into the adj module, since if the
complete adjs were done by the ip-neighbour module and incomplete ones
by adj module, that would mean two walks of the adj DB, as it is not
possible to walk only a specific type.
UT is updated to include the missing case.

Signed-off-by: Neale Ranns <neale@graphiant.com>
Signed-off-by: Ivan Shvedunov <ivan4th@gmail.com>
Change-Id: I36af94976c645bdd0d4d3bc0093b24d7d077e9d7

6 files changed, 80 insertions, 44 deletions

diff --git a/src/vnet/adj/adj_glean.c b/src/vnet/adj/adj_glean.c
index 8df104bd19d..e8ca043662f 100644
--- a/src/vnet/adj/adj_glean.c
+++ b/src/vnet/adj/adj_glean.c
@@ -187,12 +187,6 @@ adj_glean_update_rewrite_walk (adj_index_t ai,
 }
 
 void
-adj_glean_update_rewrite_itf (u32 sw_if_index)
-{
-    adj_glean_walk (sw_if_index, adj_glean_update_rewrite_walk, NULL);
-}
-
-void
 adj_glean_walk (u32 sw_if_index,
                 adj_walk_cb_t cb,
                 void *data)
@@ -425,6 +419,16 @@ adj_glean_interface_delete (vnet_main_t * vnm,
 
 VNET_SW_INTERFACE_ADD_DEL_FUNCTION(adj_glean_interface_delete);
 
+/**
+ * Callback function invoked when an interface's MAC Address changes
+ */
+static void
+adj_glean_ethernet_change_mac (ethernet_main_t * em,
+                             u32 sw_if_index, uword opaque)
+{
+    adj_glean_walk (sw_if_index, adj_glean_update_rewrite_walk, NULL);
+}
+
 u8*
 format_adj_glean (u8* s, va_list *ap)
 {
@@ -509,4 +513,10 @@ void
 adj_glean_module_init (void)
 {
     dpo_register(DPO_ADJACENCY_GLEAN, &adj_glean_dpo_vft, glean_nodes);
+
+    ethernet_address_change_ctx_t ctx = {
+        .function = adj_glean_ethernet_change_mac,
+        .function_opaque = 0,
+    };
+    vec_add1 (ethernet_main.address_change_callbacks, ctx);
 }
diff --git a/src/vnet/adj/adj_glean.h b/src/vnet/adj/adj_glean.h
index a06b9e81616..9e25fd9c919 100644
--- a/src/vnet/adj/adj_glean.h
+++ b/src/vnet/adj/adj_glean.h
@@ -67,7 +67,6 @@ extern adj_index_t adj_glean_get(fib_protocol_t proto,
  * glean behaviour on an adjacency liked to a connected prefix.
  */
 extern void adj_glean_update_rewrite(adj_index_t adj_index);
-extern void adj_glean_update_rewrite_itf(u32 sw_if_index);
 
 /**
  * Return the source address from the glean
diff --git a/src/vnet/adj/adj_nbr.c b/src/vnet/adj/adj_nbr.c
index 3344d6e47cc..8524c6c83ae 100644
--- a/src/vnet/adj/adj_nbr.c
+++ b/src/vnet/adj/adj_nbr.c
@@ -910,13 +910,40 @@ adj_nbr_interface_add_del (vnet_main_t * vnm,
     }
 
     return (NULL);
-   
 }
 
 VNET_SW_INTERFACE_ADD_DEL_FUNCTION(adj_nbr_interface_add_del);
 
 
 static adj_walk_rc_t
+adj_nbr_ethernet_mac_change_one (adj_index_t ai,
+                                 void *arg)
+{
+    vnet_update_adjacency_for_sw_interface(vnet_get_main(),
+                                           adj_get_sw_if_index(ai),
+                                           ai);
+
+    return (ADJ_WALK_RC_CONTINUE);
+}
+
+/**
+ * Callback function invoked when an interface's MAC Address changes
+ */
+static void
+adj_nbr_ethernet_change_mac (ethernet_main_t * em,
+                             u32 sw_if_index, uword opaque)
+{
+    fib_protocol_t proto;
+
+    FOR_EACH_FIB_IP_PROTOCOL(proto)
+    {
+	adj_nbr_walk(sw_if_index, proto,
+		     adj_nbr_ethernet_mac_change_one,
+		     NULL);
+    }
+}
+
+static adj_walk_rc_t
 adj_nbr_show_one (adj_index_t ai,
 		  void *arg)
 {
@@ -1156,4 +1183,10 @@ adj_nbr_module_init (void)
     dpo_register(DPO_ADJACENCY_INCOMPLETE,
                  &adj_nbr_incompl_dpo_vft,
                  nbr_incomplete_nodes);
+
+    ethernet_address_change_ctx_t ctx = {
+        .function = adj_nbr_ethernet_change_mac,
+        .function_opaque = 0,
+    };
+    vec_add1 (ethernet_main.address_change_callbacks, ctx);
 }
diff --git a/src/vnet/ethernet/interface.c b/src/vnet/ethernet/interface.c
index f72b4930049..d287748c0e6 100644
--- a/src/vnet/ethernet/interface.c
+++ b/src/vnet/ethernet/interface.c
@@ -216,6 +216,7 @@ ethernet_update_adjacency (vnet_main_t * vnm, u32 sw_if_index, u32 ai)
 	  adj_glean_update_rewrite (ai);
 	  break;
 	case IP_LOOKUP_NEXT_ARP:
+	case IP_LOOKUP_NEXT_REWRITE:
 	  ip_neighbor_update (vnm, ai);
 	  break;
 	case IP_LOOKUP_NEXT_BCAST:
@@ -257,7 +258,6 @@ ethernet_update_adjacency (vnet_main_t * vnm, u32 sw_if_index, u32 ai)
 	case IP_LOOKUP_NEXT_DROP:
 	case IP_LOOKUP_NEXT_PUNT:
 	case IP_LOOKUP_NEXT_LOCAL:
-	case IP_LOOKUP_NEXT_REWRITE:
 	case IP_LOOKUP_NEXT_MCAST_MIDCHAIN:
 	case IP_LOOKUP_NEXT_MIDCHAIN:
 	case IP_LOOKUP_NEXT_ICMP_ERROR:
diff --git a/src/vnet/ip-neighbor/ip_neighbor.c b/src/vnet/ip-neighbor/ip_neighbor.c
index 8637e16fd8e..6c97356dd98 100644
--- a/src/vnet/ip-neighbor/ip_neighbor.c
+++ b/src/vnet/ip-neighbor/ip_neighbor.c
@@ -692,13 +692,18 @@ ip_neighbor_update (vnet_main_t * vnm, adj_index_t ai)
 	  ip_neighbor_probe (adj);
 	}
       break;
+    case IP_LOOKUP_NEXT_REWRITE:
+      /* Update of an existing rewrite adjacency happens e.g. when the
+       * interface's MAC address changes */
+      if (NULL != ipn)
+	ip_neighbor_mk_complete (ai, ipn);
+      break;
     case IP_LOOKUP_NEXT_GLEAN:
     case IP_LOOKUP_NEXT_BCAST:
     case IP_LOOKUP_NEXT_MCAST:
     case IP_LOOKUP_NEXT_DROP:
     case IP_LOOKUP_NEXT_PUNT:
     case IP_LOOKUP_NEXT_LOCAL:
-    case IP_LOOKUP_NEXT_REWRITE:
     case IP_LOOKUP_NEXT_MCAST_MIDCHAIN:
     case IP_LOOKUP_NEXT_MIDCHAIN:
     case IP_LOOKUP_NEXT_ICMP_ERROR:
@@ -1142,31 +1147,6 @@ ip6_neighbor_proxy_del (u32 sw_if_index, const ip6_address_t * addr)
   return -1;
 }
 
-static void
-ip_neighbor_ethernet_change_mac (ethernet_main_t * em,
-				 u32 sw_if_index, uword opaque)
-{
-  ip_neighbor_t *ipn;
-
-  IP_NEIGHBOR_DBG ("mac-change: %U",
-		   format_vnet_sw_if_index_name, vnet_get_main (),
-		   sw_if_index);
-
-  /* *INDENT-OFF* */
-  pool_foreach (ipn, ip_neighbor_pool)
-   {
-    if (ipn->ipn_key->ipnk_sw_if_index == sw_if_index)
-      adj_nbr_walk_nh (ipn->ipn_key->ipnk_sw_if_index,
-                       ip_address_family_to_fib_proto(ip_neighbor_get_af(ipn)),
-                       &ip_addr_46(&ipn->ipn_key->ipnk_ip),
-                       ip_neighbor_mk_complete_walk,
-                       ipn);
-  }
-  /* *INDENT-ON* */
-
-  adj_glean_update_rewrite_itf (sw_if_index);
-}
-
 void
 ip_neighbor_populate (ip_address_family_t af, u32 sw_if_index)
 {
@@ -1806,14 +1786,6 @@ ip_neighbor_init (vlib_main_t * vm)
     };
     vec_add1 (ip6_main.table_bind_callbacks, cb);
   }
-  {
-    ethernet_address_change_ctx_t ctx = {
-      .function = ip_neighbor_ethernet_change_mac,
-      .function_opaque = 0,
-    };
-    vec_add1 (ethernet_main.address_change_callbacks, ctx);
-  }
-
   ipn_logger = vlib_log_register_class ("ip", "neighbor");
 
   ip_address_family_t af;
diff --git a/test/test_neighbor.py b/test/test_neighbor.py
index b33a70b2a3c..e893085cfdc 100644
--- a/test/test_neighbor.py
+++ b/test/test_neighbor.py
@@ -1372,7 +1372,7 @@ class ARPTestCase(VppTestCase):
 
     def test_arp_incomplete(self):
         """ ARP Incomplete"""
-        self.pg1.generate_remote_hosts(3)
+        self.pg1.generate_remote_hosts(4)
 
         p0 = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
               IP(src=self.pg0.remote_ip4,
@@ -1384,6 +1384,11 @@ class ARPTestCase(VppTestCase):
                  dst=self.pg1.remote_hosts[2].ip4) /
               UDP(sport=1234, dport=1234) /
               Raw())
+        p2 = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
+              IP(src=self.pg0.remote_ip4,
+                 dst="1.1.1.1") /
+              UDP(sport=1234, dport=1234) /
+              Raw())
 
         #
         # a packet to an unresolved destination generates an ARP request
@@ -1405,6 +1410,18 @@ class ARPTestCase(VppTestCase):
         static_arp.add_vpp_config()
 
         #
+        # add a route through remote host 3 hence we get an incomplete
+        #
+        VppIpRoute(self, "1.1.1.1", 32,
+                   [VppRoutePath(self.pg1.remote_hosts[3].ip4,
+                                 self.pg1.sw_if_index)]).add_vpp_config()
+        rx = self.send_and_expect(self.pg0, [p2], self.pg1)
+        self.verify_arp_req(rx[0],
+                            self.pg1.local_mac,
+                            self.pg1.local_ip4,
+                            self.pg1._remote_hosts[3].ip4)
+
+        #
         # change the interface's MAC
         #
         self.vapi.sw_interface_set_mac_address(self.pg1.sw_if_index,
@@ -1418,6 +1435,11 @@ class ARPTestCase(VppTestCase):
                             "00:00:00:33:33:33",
                             self.pg1.local_ip4,
                             self.pg1._remote_hosts[2].ip4)
+        rx = self.send_and_expect(self.pg0, [p2], self.pg1)
+        self.verify_arp_req(rx[0],
+                            "00:00:00:33:33:33",
+                            self.pg1.local_ip4,
+                            self.pg1._remote_hosts[3].ip4)
 
         #
         # packets to the resolved host also have the new source mac