FIB Interpose Source

The interpose source allows the source/provider to insert/interpose
a DPO in the forwarding chain of the FIB entry ahead of the forwarding
provided by the next best source. For example if the API source (i.e
the 'control plane') has provided an adjacency for forwarding, then
an interpose source (e.g. a monitoring service) couold interpose a
replicatte DPO to copy the traffic to another location AND forward
using the API's adjacency.
To use the interose feature an existing source (i.e FIB_SOURCE_PLUGIN_HI)
cn specifiy as a flag FIB_ENTRY_FLAG_INTERPOSE and provide a DPO to
interpose. One might also consider using interpose in conjunction with
FIB_ENTRY_FLAG_COVER_INHERIT to ensure the interpose object affects
all prefixes in the sub-tree.

Change-Id: I8b2737b985f8f7c08123406d0491881def347b52
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 18 insertions, 17 deletions

diff --git a/src/vnet/fib/fib_entry_src_interface.c b/src/vnet/fib/fib_entry_src_interface.c
index f79be72c45a..4ce4f14ab4e 100644
--- a/src/vnet/fib/fib_entry_src_interface.c
+++ b/src/vnet/fib/fib_entry_src_interface.c
@@ -27,8 +27,8 @@
 static void
 fib_entry_src_interface_init (fib_entry_src_t *src)
 {
-    src->interface.fesi_cover = FIB_NODE_INDEX_INVALID;
-    src->interface.fesi_sibling = FIB_NODE_INDEX_INVALID;
+    src->u.interface.fesi_cover = FIB_NODE_INDEX_INVALID;
+    src->u.interface.fesi_sibling = FIB_NODE_INDEX_INVALID;
 }
 
 static void
@@ -74,7 +74,7 @@ fib_entry_src_interface_path_swap (fib_entry_src_t *src,
         {
             /*
              * the connected prefix will link to a glean on a non-p2p
-             * interface.
+             * u.interface.
              */
             adj->sub_type.glean.receive_addr = entry->fe_prefix.fp_addr;
         }
@@ -98,15 +98,15 @@ fib_entry_src_interface_activate (fib_entry_src_t *src,
 	 * during an attached export of the cover, this local prefix is
 	 * also exported
 	 */
-	src->interface.fesi_cover =
+	src->u.interface.fesi_cover =
 	    fib_table_get_less_specific(fib_entry->fe_fib_index,
 					&fib_entry->fe_prefix);
 
-	ASSERT(FIB_NODE_INDEX_INVALID != src->interface.fesi_cover);
+	ASSERT(FIB_NODE_INDEX_INVALID != src->u.interface.fesi_cover);
 
-	cover = fib_entry_get(src->interface.fesi_cover);
+	cover = fib_entry_get(src->u.interface.fesi_cover);
 
-	src->interface.fesi_sibling =
+	src->u.interface.fesi_sibling =
 	    fib_entry_cover_track(cover, fib_entry_get_index(fib_entry));
     }
 
@@ -127,13 +127,13 @@ fib_entry_src_interface_deactivate (fib_entry_src_t *src,
     /*
      * remove the depednecy on the covering entry
      */
-    if (FIB_NODE_INDEX_INVALID != src->interface.fesi_cover)
+    if (FIB_NODE_INDEX_INVALID != src->u.interface.fesi_cover)
     {
-	cover = fib_entry_get(src->interface.fesi_cover);
+	cover = fib_entry_get(src->u.interface.fesi_cover);
 
-	fib_entry_cover_untrack(cover, src->interface.fesi_sibling);
+	fib_entry_cover_untrack(cover, src->u.interface.fesi_sibling);
 
-	src->interface.fesi_cover = FIB_NODE_INDEX_INVALID;
+	src->u.interface.fesi_cover = FIB_NODE_INDEX_INVALID;
     }
 }
 
@@ -146,7 +146,7 @@ fib_entry_src_interface_cover_change (fib_entry_src_t *src,
 	.bw_reason = FIB_NODE_BW_REASON_FLAG_NONE,
     };
 
-    if (FIB_NODE_INDEX_INVALID == src->interface.fesi_cover)
+    if (FIB_NODE_INDEX_INVALID == src->u.interface.fesi_cover)
     {
 	/*
 	 * not tracking the cover. surprised we got poked?
@@ -159,8 +159,9 @@ fib_entry_src_interface_cover_change (fib_entry_src_t *src,
      * entry inserted benaeth it. That does not necessarily mean that this
      * entry is covered by the new prefix. check that
      */
-    if (src->rr.fesr_cover != fib_table_get_less_specific(fib_entry->fe_fib_index,
-							  &fib_entry->fe_prefix))
+    if (src->u.interface.fesi_cover !=
+        fib_table_get_less_specific(fib_entry->fe_fib_index,
+                                    &fib_entry->fe_prefix))
     {
 	fib_entry_src_interface_deactivate(src, fib_entry);
 	fib_entry_src_interface_activate(src, fib_entry);
@@ -177,9 +178,9 @@ fib_entry_src_interface_installed (fib_entry_src_t *src,
      */
     fib_entry_t *cover;
 
-    if (FIB_NODE_INDEX_INVALID != src->interface.fesi_cover)
+    if (FIB_NODE_INDEX_INVALID != src->u.interface.fesi_cover)
     {
-	cover = fib_entry_get(src->interface.fesi_cover);
+	cover = fib_entry_get(src->u.interface.fesi_cover);
 
 	fib_attached_export_covered_added(cover,
 					  fib_entry_get_index(fib_entry));
@@ -190,7 +191,7 @@ static u8*
 fib_entry_src_interface_format (fib_entry_src_t *src,
 				u8* s)
 {
-    return (format(s, " cover:%d", src->interface.fesi_cover));
+    return (format(s, " cover:%d", src->u.interface.fesi_cover));
 }
 
 const static fib_entry_src_vft_t interface_src_vft = {