This patch changes BGP from only listening mode for BFD status updates to interactive mode of dynamically registering/deregistering BFD enabled peers with PTM/BFD through zebra. Peer is registered with BFD when it goes into established state and de-registers when it goes out of establish state.

This patch also adds BFD multihop support for BGP. Whether a peer is multi-hop or single hop is determined internally. All IGP peers are considered as multi-hop peers. EBGP peers are considered as single hop unless configured as multi-hop.

BGP BFD command enhancement to configure BFD parameters (detect multiplier, min rx and min tx).

router bgp <as-number>
  neighbor <name/ip-address> bfd <detect mult> <min rx> <min tx>

Signed-off-by: Radhika Mahankali <radhika@cumulusnetworks.com>
Reviewed-by:   Dinesh G Dutt <ddutt@cumulusnetworks.com>
Reviewed-by:   Vipin Kumar <vipin@cumulusnetworks.com>
Reviewed-by:   Kanna Rajagopal <kanna@cumulusnetworks.com>

1 files changed, 122 insertions, 0 deletions

diff --git a/zebra/zebra_ptm_redistribute.c b/zebra/zebra_ptm_redistribute.c
new file mode 100644
index 000000000..5d231de85
--- /dev/null
+++ b/zebra/zebra_ptm_redistribute.c
@@ -0,0 +1,122 @@
+/**
+ * @copyright Copyright (C) 2015 Cumulus Networks, Inc.
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <zebra.h>
+#include "prefix.h"
+#include "vty.h"
+#include "stream.h"
+#include "zebra/zserv.h"
+
+/* master zebra server structure */
+extern struct zebra_t zebrad;
+
+int
+zsend_interface_bfd_update (int cmd, struct zserv *client,
+                            struct interface *ifp, struct prefix *dp,
+                            struct prefix *sp)
+{
+  int blen;
+  struct stream *s;
+
+  /* Check this client need interface information. */
+  if (! client->ifinfo)
+    return 0;
+
+  s = client->obuf;
+  stream_reset (s);
+
+  zserv_create_header (s, cmd);
+  if (ifp)
+    stream_putl (s, ifp->ifindex);
+  else
+    stream_putl (s, 0);
+
+  /* BFD destination prefix information. */
+  stream_putc (s, dp->family);
+  blen = prefix_blen (dp);
+  stream_put (s, &dp->u.prefix, blen);
+  stream_putc (s, dp->prefixlen);
+
+  /* BFD source prefix information. */
+  stream_putc (s, sp->family);
+  blen = prefix_blen (sp);
+  stream_put (s, &sp->u.prefix, blen);
+  stream_putc (s, sp->prefixlen);
+
+  /* Write packet size. */
+  stream_putw_at (s, 0, stream_get_endp (s));
+
+  client->if_bfd_cnt++;
+  return zebra_server_send_message(client);
+}
+
+void
+zebra_interface_bfd_update (struct interface *ifp, struct prefix *dp,
+                            struct prefix *sp)
+{
+  struct listnode *node, *nnode;
+  struct zserv *client;
+
+  for (ALL_LIST_ELEMENTS (zebrad.client_list, node, nnode, client))
+    {
+      /* Supporting for OSPF and BGP */
+      if (client->proto != ZEBRA_ROUTE_OSPF && client->proto != ZEBRA_ROUTE_BGP)
+        continue;
+
+      /* Notify to the protocol daemons. */
+      zsend_interface_bfd_update (ZEBRA_INTERFACE_BFD_DEST_DOWN, client, ifp,
+                                    dp, sp);
+    }
+}
+
+int
+zsend_bfd_peer_replay (int cmd, struct zserv *client)
+{
+  struct stream *s;
+
+  s = client->obuf;
+  stream_reset (s);
+
+  zserv_create_header (s, cmd);
+
+  /* Write packet size. */
+  stream_putw_at (s, 0, stream_get_endp (s));
+
+  client->bfd_peer_replay_cnt++;
+  return zebra_server_send_message(client);
+}
+
+void
+zebra_bfd_peer_replay_req (void)
+{
+  struct listnode *node, *nnode;
+  struct zserv *client;
+
+  for (ALL_LIST_ELEMENTS (zebrad.client_list, node, nnode, client))
+    {
+      /* Supporting for BGP */
+      if (client->proto != ZEBRA_ROUTE_BGP)
+        continue;
+
+      /* Notify to the protocol daemons. */
+      zsend_bfd_peer_replay (ZEBRA_BFD_DEST_REPLAY, client);
+    }
+}