Check change in unnumbered setting before updating IP enabled state

Change-Id: I6424a083ec889961ba4d0cd1df8348f20436be14
Signed-off-by: Neale Ranns <nranns@cisco.com>

2 files changed, 23 insertions, 6 deletions

diff --git a/src/vnet/interface_api.c b/src/vnet/interface_api.c
index 44798c8b33b..39c062714bf 100644
--- a/src/vnet/interface_api.c
+++ b/src/vnet/interface_api.c
@@ -433,6 +433,7 @@ static void vl_api_sw_interface_set_unnumbered_t_handler
   vnet_main_t *vnm = vnet_get_main ();
   u32 sw_if_index = ntohl (mp->sw_if_index);
   u32 unnumbered_sw_if_index = ntohl (mp->unnumbered_sw_if_index);
+  u32 was_unnum;
 
   /*
    * The API message field names are backwards from
@@ -454,6 +455,7 @@ static void vl_api_sw_interface_set_unnumbered_t_handler
 
   vnet_sw_interface_t *si =
     vnet_get_sw_interface (vnm, unnumbered_sw_if_index);
+  was_unnum = (si->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED);
 
   if (mp->is_add)
     {
@@ -480,8 +482,12 @@ static void vl_api_sw_interface_set_unnumbered_t_handler
       ip6_main.lookup_main.if_address_pool_index_by_sw_if_index
 	[unnumbered_sw_if_index] = ~0;
     }
-  ip4_sw_interface_enable_disable (unnumbered_sw_if_index, mp->is_add);
-  ip6_sw_interface_enable_disable (unnumbered_sw_if_index, mp->is_add);
+
+  if (was_unnum != (si->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED))
+    {
+      ip4_sw_interface_enable_disable (unnumbered_sw_if_index, mp->is_add);
+      ip6_sw_interface_enable_disable (unnumbered_sw_if_index, mp->is_add);
+    }
 
 done:
   REPLY_MACRO (VL_API_SW_INTERFACE_SET_UNNUMBERED_REPLY);
diff --git a/src/vnet/interface_cli.c b/src/vnet/interface_cli.c
index ec8530da299..c1566551669 100644
--- a/src/vnet/interface_cli.c
+++ b/src/vnet/interface_cli.c
@@ -844,6 +844,7 @@ set_unnumbered (vlib_main_t * vm,
   vnet_sw_interface_t *si;
   int is_set = 0;
   int is_del = 0;
+  u32 was_unnum;
 
   if (unformat (input, "%U use %U",
 		unformat_vnet_sw_interface, vnm, &unnumbered_sw_if_index,
@@ -858,12 +859,13 @@ set_unnumbered (vlib_main_t * vm,
 			      format_unformat_error, input);
 
   si = vnet_get_sw_interface (vnm, unnumbered_sw_if_index);
+  was_unnum = (si->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED);
+
   if (is_del)
     {
       si->flags &= ~(VNET_SW_INTERFACE_FLAG_UNNUMBERED);
       si->unnumbered_sw_if_index = (u32) ~ 0;
-      ip4_sw_interface_enable_disable (unnumbered_sw_if_index, 0);
-      ip6_sw_interface_enable_disable (unnumbered_sw_if_index, 0);
+
       ip4_main.lookup_main.if_address_pool_index_by_sw_if_index
 	[unnumbered_sw_if_index] = ~0;
       ip6_main.lookup_main.if_address_pool_index_by_sw_if_index
@@ -873,8 +875,7 @@ set_unnumbered (vlib_main_t * vm,
     {
       si->flags |= VNET_SW_INTERFACE_FLAG_UNNUMBERED;
       si->unnumbered_sw_if_index = inherit_from_sw_if_index;
-      ip4_sw_interface_enable_disable (unnumbered_sw_if_index, 1);
-      ip6_sw_interface_enable_disable (unnumbered_sw_if_index, 1);
+
       ip4_main.lookup_main.if_address_pool_index_by_sw_if_index
 	[unnumbered_sw_if_index] =
 	ip4_main.lookup_main.if_address_pool_index_by_sw_if_index
@@ -884,6 +885,16 @@ set_unnumbered (vlib_main_t * vm,
 	ip6_main.lookup_main.if_address_pool_index_by_sw_if_index
 	[inherit_from_sw_if_index];
     }
+  else
+    {
+      return (0);
+    }
+
+  if (was_unnum != (si->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED))
+    {
+      ip4_sw_interface_enable_disable (unnumbered_sw_if_index, !is_del);
+      ip6_sw_interface_enable_disable (unnumbered_sw_if_index, !is_del);
+    }
 
   return 0;
 }