Nest: Add command to request graceful restart

When 'graceful down' command is entered, protocols are shut down
with regard to graceful restart. Namely Kernel protocol does
not remove routes and BGP protocol does not send notification,
just closes the connection.

1 files changed, 19 insertions, 4 deletions

diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c
index 470c6ff5..cfc31ed0 100644
--- a/proto/bgp/bgp.c
+++ b/proto/bgp/bgp.c
@@ -422,7 +422,7 @@ bgp_update_startup_delay(struct bgp_proto *p)
 }
 
 static void
-bgp_graceful_close_conn(struct bgp_conn *conn, uint subcode, byte *data, uint len)
+bgp_graceful_close_conn(struct bgp_conn *conn, int subcode, byte *data, uint len)
 {
   switch (conn->state)
   {
@@ -438,7 +438,13 @@ bgp_graceful_close_conn(struct bgp_conn *conn, uint subcode, byte *data, uint le
   case BS_OPENSENT:
   case BS_OPENCONFIRM:
   case BS_ESTABLISHED:
-    bgp_error(conn, 6, subcode, data, len);
+    if (subcode < 0)
+    {
+      bgp_conn_enter_close_state(conn);
+      bgp_schedule_packet(conn, NULL, PKT_SCHEDULE_CLOSE);
+    }
+    else
+      bgp_error(conn, 6, subcode, data, len);
     return;
 
   default:
@@ -501,7 +507,7 @@ bgp_spawn(struct bgp_proto *pp, ip_addr remote_ip)
 }
 
 void
-bgp_stop(struct bgp_proto *p, uint subcode, byte *data, uint len)
+bgp_stop(struct bgp_proto *p, int subcode, byte *data, uint len)
 {
   proto_notify_state(&p->p, PS_STOP);
   bgp_graceful_close_conn(&p->outgoing_conn, subcode, data, len);
@@ -1555,7 +1561,7 @@ static int
 bgp_shutdown(struct proto *P)
 {
   struct bgp_proto *p = (struct bgp_proto *) P;
-  uint subcode = 0;
+  int subcode = 0;
 
   char *message = NULL;
   byte *data = NULL;
@@ -1576,6 +1582,7 @@ bgp_shutdown(struct proto *P)
 
   case PDC_CMD_DISABLE:
   case PDC_CMD_SHUTDOWN:
+  shutdown:
     subcode = 2; // Errcode 6, 2 - administrative shutdown
     message = P->message;
     break;
@@ -1585,6 +1592,14 @@ bgp_shutdown(struct proto *P)
     message = P->message;
     break;
 
+  case PDC_CMD_GR_DOWN:
+    if ((p->cf->gr_mode != BGP_GR_ABLE) &&
+	(p->cf->llgr_mode != BGP_LLGR_ABLE))
+      goto shutdown;
+
+    subcode = -1; // Do not send NOTIFICATION, just close the connection
+    break;
+
   case PDC_RX_LIMIT_HIT:
   case PDC_IN_LIMIT_HIT:
     subcode = 1; // Errcode 6, 1 - max number of prefixes reached