Support of BFD status in Quagga

Ticket:CM-6802, CM-6952
Reviewed By: Donald, Kanna
Testing Done:

Double commit of b76943235e09472ec174edcf7204fc82d27fe966 from br2.5. But, manually resolved all the compilation errors. Also, modified the shows to support the json format which was not supported in br2.5.

CM-6802 – Currently, BFD session status can be monitored only through ptmctl. There is no way to check the BFD status of a peer/neighbor through Quagga. Debugging becomes easier if BFD status is shown in Quagga too. BFD status is relevant when it is shown against the BGP peer/OSPF neighbor. For, this following code changes have been done:
   - Only down messages from PTM were being propagated from Zebra daemon to clients (bgpd, ospfd and ospf6d). Now, both up and down messages are redistributed to the clients from zebra. BFD status field has been added to the messaging. Handling of BFD session up messages has been added to the client code. BGP/OSPF neighbor is brought down only if the old BFD session status is ‘Up’ to handle extra/initial down messages.
   - BFD status and last update timestamp fields have been added to the common BFD info structure. Also, common show functions for showing BFD information have been added to BFD lib.
   - Modified the BGP neighbor show functions to call common BFD lib functions.
   - For ospf and ospf6, BFD information was maintained only at interface level. To show BFD status per neighbor, BFD information has been added at neighbor level too. “show ip ospf interface”, “show ip ospf neighbor detail”, “show ipv6 ospf6 interface” and “show ipv6 ospf6 neighbor detail” output have been modified to show BFD information.

CM-6952 - IBGP peers were always assumed to be multi-hop since there was no easy way to determine whether an IBGP peer was single hop or multihop unlike EBGP. But, this is causing problem with IBGP link local peers since BFD doesn't allow multihop BFD session with link local IP addresses. Link local peers were discovered when the interface peering was enabled. Interface peering is always singlehop. So, added checks to treat all interface based peers as single hop irrespective of whether the peer is IBGP or EBGP.

1 files changed, 151 insertions, 1 deletions

diff --git a/lib/bfd.c b/lib/bfd.c
index 862a95dac..613c71487 100644
--- a/lib/bfd.c
+++ b/lib/bfd.c
@@ -44,6 +44,8 @@ bfd_info_create(void)
   bfd_info = XCALLOC (MTYPE_BFD_INFO, sizeof (struct bfd_info));
   assert(bfd_info);
 
+  bfd_info->status = BFD_STATUS_UNKNOWN;
+  bfd_info->last_update = 0;
   return bfd_info;
 }
 
@@ -247,7 +249,8 @@ bfd_get_command_dbg_str(int command)
  *                     went down from the message sent from Zebra to clients.
  */
 struct interface *
-bfd_get_peer_info (struct stream *s, struct prefix *dp, struct prefix *sp)
+bfd_get_peer_info (struct stream *s, struct prefix *dp, struct prefix *sp,
+                    int *status)
 {
   unsigned int ifindex;
   struct interface *ifp = NULL;
@@ -275,6 +278,9 @@ bfd_get_peer_info (struct stream *s, struct prefix *dp, struct prefix *sp)
   stream_get (&dp->u.prefix, s, plen);
   dp->prefixlen = stream_getc (s);
 
+  /* Get BFD status. */
+  *status = stream_getl (s);
+
   if (sp)
     {
       sp->family = stream_getc (s);
@@ -285,3 +291,147 @@ bfd_get_peer_info (struct stream *s, struct prefix *dp, struct prefix *sp)
     }
   return ifp;
 }
+
+/*
+ * bfd_get_status_str - Convert BFD status to a display string.
+ */
+const char *
+bfd_get_status_str(int status)
+{
+  switch (status)
+  {
+    case BFD_STATUS_DOWN:
+      return "Down";
+    case BFD_STATUS_UP:
+      return "Up";
+    case BFD_STATUS_UNKNOWN:
+    default:
+      return "Unknown";
+  }
+}
+
+/*
+ * bfd_last_update - Calculate the last BFD update time and convert it
+ *                   into a dd:hh:mm:ss display format.
+ */
+static void
+bfd_last_update (time_t last_update, char *buf, size_t len)
+{
+  time_t curr;
+  time_t diff;
+  struct tm *tm;
+  struct timeval tv;
+
+  /* If no BFD satatus update has ever been received, print `never'. */
+  if (last_update == 0)
+    {
+      snprintf (buf, len, "never");
+      return;
+    }
+
+  /* Get current time. */
+  quagga_gettime(QUAGGA_CLK_MONOTONIC, &tv);
+  curr = tv.tv_sec;
+  diff = curr - last_update;
+  tm = gmtime (&diff);
+
+  snprintf (buf, len, "%d:%02d:%02d:%02d",
+            tm->tm_yday, tm->tm_hour, tm->tm_min, tm->tm_sec);
+}
+
+/*
+ * bfd_show_param - Show the BFD parameter information.
+ */
+void
+bfd_show_param(struct vty *vty, struct bfd_info *bfd_info, int bfd_tag,
+                int extra_space, u_char use_json, json_object *json_obj)
+{
+  json_object *json_bfd = NULL;
+
+  if (!bfd_info)
+    return;
+
+  if (use_json)
+    {
+      if (bfd_tag)
+        json_bfd = json_object_new_object();
+      else
+        json_bfd = json_obj;
+
+      json_object_int_add(json_bfd, "detectMultiplier", bfd_info->detect_mult);
+      json_object_int_add(json_bfd, "rxMinInterval", bfd_info->required_min_rx);
+      json_object_int_add(json_bfd, "txMinInterval", bfd_info->desired_min_tx);
+      if (bfd_tag)
+        json_object_object_add(json_obj, "peerBfdInfo", json_bfd);
+    }
+  else
+    {
+      vty_out (vty, "  %s%sDetect Mul: %d, Min Rx interval: %d,"
+                " Min Tx interval: %d%s",
+                    (extra_space) ? "  ": "", (bfd_tag) ? "BFD: " : "  ",
+                    bfd_info->detect_mult, bfd_info->required_min_rx,
+                    bfd_info->desired_min_tx, VTY_NEWLINE);
+    }
+}
+
+/*
+ * bfd_show_status - Show the BFD status information.
+ */
+static void
+bfd_show_status(struct vty *vty, struct bfd_info *bfd_info, int bfd_tag,
+                int extra_space, u_char use_json, json_object *json_bfd)
+{
+  char time_buf[32];
+
+  if (!bfd_info)
+    return;
+
+  bfd_last_update(bfd_info->last_update, time_buf, 32);
+  if (use_json)
+    {
+      json_object_string_add(json_bfd, "status",
+                              bfd_get_status_str(bfd_info->status));
+      json_object_string_add(json_bfd, "lastUpdate", time_buf);
+    }
+  else
+    {
+      vty_out (vty, "  %s%sStatus: %s, Last update: %s%s",
+                  (extra_space) ? "  ": "", (bfd_tag) ? "BFD: " : "  ",
+                  bfd_get_status_str(bfd_info->status), time_buf, VTY_NEWLINE);
+    }
+}
+
+/*
+ * bfd_show_info - Show the BFD information.
+ */
+void
+bfd_show_info(struct vty *vty, struct bfd_info *bfd_info, int multihop,
+              int extra_space, u_char use_json, json_object *json_obj)
+{
+  json_object *json_bfd = NULL;
+
+  if (!bfd_info)
+    return;
+
+  if (use_json)
+    {
+      json_bfd = json_object_new_object();
+      if (multihop)
+        json_object_string_add(json_bfd, "type", "multi hop");
+      else
+        json_object_string_add(json_bfd, "type", "single hop");
+    }
+  else
+    {
+      vty_out (vty, "  %sBFD: Type: %s%s", (extra_space) ? "  " : "",
+              (multihop) ? "multi hop" : "single hop", VTY_NEWLINE);
+    }
+
+  bfd_show_param(vty, bfd_info, 0, extra_space, use_json, json_bfd);
+  bfd_show_status(vty, bfd_info, 0, extra_space, use_json, json_bfd);
+
+  if (use_json)
+    json_object_object_add(json_obj, "peerBfdInfo", json_bfd);
+  else
+    vty_out (vty, "%s", VTY_NEWLINE);
+}