BGP: implement Adj-RIB-Out

The patch implements optional internal export table to a channel and
hooks it to BGP so it can be used as Adj-RIB-Out. When enabled, all
exported (post-filtered) routes are stored there. An export table can be
examined using e.g. 'show route export table bgp1.ipv4'.

1 files changed, 26 insertions, 0 deletions

diff --git a/nest/proto.c b/nest/proto.c
index 18cf214b..54955bdd 100644
--- a/nest/proto.c
+++ b/nest/proto.c
@@ -317,6 +317,13 @@ channel_reset_import(struct channel *c)
   rt_prune_sync(c->in_table, 1);
 }
 
+static void
+channel_reset_export(struct channel *c)
+{
+  /* Just free the routes */
+  rt_prune_sync(c->out_table, 1);
+}
+
 /* Called by protocol to activate in_table */
 void
 channel_setup_in_table(struct channel *c)
@@ -331,6 +338,18 @@ channel_setup_in_table(struct channel *c)
   c->reload_event = ev_new_init(c->proto->pool, channel_reload_loop, c);
 }
 
+/* Called by protocol to activate out_table */
+void
+channel_setup_out_table(struct channel *c)
+{
+  struct rtable_config *cf = mb_allocz(c->proto->pool, sizeof(struct rtable_config));
+  cf->name = "export";
+  cf->addr_type = c->net_type;
+
+  c->out_table = mb_allocz(c->proto->pool, sizeof(struct rtable));
+  rt_setup(c->proto->pool, c->out_table, cf);
+}
+
 
 static void
 channel_do_start(struct channel *c)
@@ -376,6 +395,7 @@ channel_do_down(struct channel *c)
 
   c->in_table = NULL;
   c->reload_event = NULL;
+  c->out_table = NULL;
 
   CALL(c->channel->cleanup, c);
 
@@ -411,6 +431,9 @@ channel_set_state(struct channel *c, uint state)
     if (c->in_table && (cs == CS_UP))
       channel_reset_import(c);
 
+    if (c->out_table && (cs == CS_UP))
+      channel_reset_export(c);
+
     break;
 
   case CS_UP:
@@ -433,6 +456,9 @@ channel_set_state(struct channel *c, uint state)
     if (c->in_table && (cs == CS_UP))
       channel_reset_import(c);
 
+    if (c->out_table && (cs == CS_UP))
+      channel_reset_export(c);
+
     channel_do_flush(c);
     break;