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.

6 files changed, 178 insertions, 8 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);
+}
diff --git a/lib/bfd.h b/lib/bfd.h
index f0051d93a..0b5743b91 100644
--- a/lib/bfd.h
+++ b/lib/bfd.h
@@ -24,6 +24,8 @@
 #ifndef _ZEBRA_BFD_H
 #define _ZEBRA_BFD_H
 
+#include "lib/json.h"
+
 #define BFD_CMD_DETECT_MULT_RANGE "<2-255> "
 #define BFD_CMD_MIN_RX_RANGE "<50-60000> "
 #define BFD_CMD_MIN_TX_RANGE "<50-60000>"
@@ -41,12 +43,18 @@
 #define BFD_FLAG_PARAM_CFG (1 << 0) /* parameters have been configured */
 #define BFD_FLAG_BFD_REG   (1 << 1) /* Peer registered with BFD */
 
+#define BFD_STATUS_UNKNOWN (1 << 0) /* BFD session status never received */
+#define BFD_STATUS_DOWN    (1 << 1) /* BFD session status is down */
+#define BFD_STATUS_UP      (1 << 2) /* BFD session status is up */
+
 struct bfd_info
 {
   u_int16_t flags;
   u_int8_t  detect_mult;
   u_int32_t desired_min_tx;
   u_int32_t required_min_rx;
+  time_t    last_update;
+  u_int8_t  status;
 };
 
 extern struct bfd_info *
@@ -72,6 +80,18 @@ extern const char *
 bfd_get_command_dbg_str(int command);
 
 extern 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);
+
+const char *
+bfd_get_status_str(int status);
+
+extern 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);
+
+extern 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);
 
 #endif /* _ZEBRA_BFD_H */
diff --git a/lib/log.c b/lib/log.c
index 64bd16458..1046f904d 100644
--- a/lib/log.c
+++ b/lib/log.c
@@ -836,7 +836,7 @@ static const struct zebra_desc_table command_types[] = {
   DESC_ENTRY   (ZEBRA_INTERFACE_NBR_ADDRESS_ADD),
   DESC_ENTRY   (ZEBRA_INTERFACE_NBR_ADDRESS_DELETE),
   DESC_ENTRY    (ZEBRA_IMPORT_CHECK_UPDATE),
-  DESC_ENTRY   (ZEBRA_INTERFACE_BFD_DEST_DOWN),
+  DESC_ENTRY   (ZEBRA_INTERFACE_BFD_DEST_UPDATE),
   DESC_ENTRY   (ZEBRA_BFD_DEST_REGISTER),
   DESC_ENTRY   (ZEBRA_BFD_DEST_DEREGISTER),
   DESC_ENTRY   (ZEBRA_BFD_DEST_UPDATE),
diff --git a/lib/zclient.c b/lib/zclient.c
index 39b6f8ec5..35b18cb95 100644
--- a/lib/zclient.c
+++ b/lib/zclient.c
@@ -1208,9 +1208,9 @@ zclient_read (struct thread *thread)
       if (zclient->interface_address_delete)
 	(*zclient->interface_address_delete) (command, zclient, length);
       break;
-    case ZEBRA_INTERFACE_BFD_DEST_DOWN:
-      if (zclient->interface_bfd_dest_down)
-	(*zclient->interface_bfd_dest_down) (command, zclient, length);
+    case ZEBRA_INTERFACE_BFD_DEST_UPDATE:
+      if (zclient->interface_bfd_dest_update)
+	(*zclient->interface_bfd_dest_update) (command, zclient, length);
       break;
     case ZEBRA_INTERFACE_NBR_ADDRESS_ADD:
       if (zclient->interface_nbr_address_add)
diff --git a/lib/zclient.h b/lib/zclient.h
index 26cae0434..6ed4fede4 100644
--- a/lib/zclient.h
+++ b/lib/zclient.h
@@ -85,7 +85,7 @@ struct zclient
   int (*interface_down) (int, struct zclient *, uint16_t);
   int (*interface_address_add) (int, struct zclient *, uint16_t);
   int (*interface_address_delete) (int, struct zclient *, uint16_t);
-  int (*interface_bfd_dest_down) (int, struct zclient *, uint16_t);
+  int (*interface_bfd_dest_update) (int, struct zclient *, uint16_t);
   int (*interface_nbr_address_add) (int, struct zclient *, uint16_t);
   int (*interface_nbr_address_delete) (int, struct zclient *, uint16_t);
   int (*ipv4_route_add) (int, struct zclient *, uint16_t);
diff --git a/lib/zebra.h b/lib/zebra.h
index 387cd6541..41de01ec2 100644
--- a/lib/zebra.h
+++ b/lib/zebra.h
@@ -429,7 +429,7 @@ struct in_pktinfo
 #define ZEBRA_NEXTHOP_UPDATE              26
 #define ZEBRA_INTERFACE_NBR_ADDRESS_ADD   27
 #define ZEBRA_INTERFACE_NBR_ADDRESS_DELETE 28
-#define ZEBRA_INTERFACE_BFD_DEST_DOWN    29
+#define ZEBRA_INTERFACE_BFD_DEST_UPDATE   29
 #define ZEBRA_IMPORT_ROUTE_REGISTER       30
 #define ZEBRA_IMPORT_ROUTE_UNREGISTER     31
 #define ZEBRA_IMPORT_CHECK_UPDATE         32