bgpd, zebra: Use next hop tracking for connected routes too

Allow next hop tracking to work with connected routes
And cleanup obsolete code in bgp_scan and bgp_import.

Signed-off-by: Dinesh Dutt <ddutt@cumulusnetworks.com>
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Edits: Paul Jakma <paul.jakma@hpe.com> Rebase re-ordering conflicts with
       NHT route-map, potential errors.

bgpd/bgp_fsm.c

@@ -42,6 +42,7 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 #include "bgpd/bgp_route.h"
 #include "bgpd/bgp_dump.h"
 #include "bgpd/bgp_open.h"
+#include "bgpd/bgp_nht.h"
 #ifdef HAVE_SNMP
 #include "bgpd/bgp_snmp.h"
 #endif /* HAVE_SNMP */
@@ -675,6 +676,7 @@ int
 bgp_start (struct peer *peer)
 {
   int status;
+  int connected = 0;
 
   if (BGP_PEER_START_SUPPRESSED (peer))
     {
@@ -713,6 +715,12 @@ bgp_start (struct peer *peer)
       return 0;
     }
 
+  /* Register to be notified on peer up */
+  if ((peer->ttl == 1) || (peer->gtsm_hops == 1))
+    connected = 1;
+
+  bgp_find_or_add_nexthop(family2afi(peer->su.sa.sa_family), NULL, peer,
+			  connected);
   status = bgp_connect (peer);
 
   switch (status)
@@ -939,6 +947,45 @@ bgp_ignore (struct peer *peer)
   return 0;
 }
 
+void
+bgp_fsm_nht_update(struct peer *peer, int valid)
+{
+  int ret = 0;
+
+  if (!peer)
+    return;
+
+  switch (peer->status)
+    {
+    case Idle:
+      if (valid)
+	BGP_EVENT_ADD(peer, BGP_Start);
+      break;
+    case Connect:
+      ret = bgp_connect_check(peer, 0);
+      if (!ret && valid)
+	{
+	  BGP_TIMER_OFF(peer->t_connect);
+	  BGP_EVENT_ADD(peer, ConnectRetry_timer_expired);
+	}
+      break;
+    case Active:
+      if (valid)
+	{
+	  BGP_TIMER_OFF(peer->t_connect);
+	  BGP_EVENT_ADD(peer, ConnectRetry_timer_expired);
+	}
+    case OpenSent:
+    case OpenConfirm:
+    case Established:
+    case Clearing:
+    case Deleted:
+    default:
+      break;
+    }
+}
+
+
 /* Finite State Machine structure */
 static const struct {
   int (*func) (struct peer *);

bgpd/bgp_fsm.h

@@ -72,6 +72,7 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
   } while (0)
 
 /* Prototypes. */
+extern void bgp_fsm_nht_update(struct peer *, int valid);
 extern int bgp_event (struct thread *);
 extern int bgp_stop (struct peer *peer);
 extern void bgp_timer_set (struct peer *);

bgpd/bgp_main.c

@@ -230,7 +230,6 @@ bgp_exit (int status)
   struct listnode *node, *nnode;
   int *socket;
   struct interface *ifp;
-  extern struct zclient *zlookup;
 
   /* it only makes sense for this to be called on a clean exit */
   assert (status == 0);
@@ -292,9 +291,6 @@ bgp_exit (int status)
   /* reverse bgp_route_map_init/route_map_init */
   route_map_finish ();
 
-  /* reverse bgp_scan_init */
-  bgp_scan_finish ();
-
   /* reverse access_list_init */
   access_list_add_hook (NULL);
   access_list_delete_hook (NULL);
@@ -319,13 +315,14 @@ bgp_exit (int status)
   bgp_address_destroy();
   bgp_scan_destroy();
   bgp_zebra_destroy();
-  if (zlookup)
-    zclient_free (zlookup);
   if (bgp_nexthop_buf)
     stream_free (bgp_nexthop_buf);
   if (bgp_ifindices_buf)
     stream_free (bgp_ifindices_buf);
 
+  /* reverse bgp_scan_init */
+  bgp_scan_finish ();
+
   /* reverse bgp_master_init */
   if (bm->master)
     thread_master_free (bm->master);

bgpd/bgp_nexthop.h

@@ -25,9 +25,6 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 #include "queue.h"
 #include "prefix.h"
 
-#define BGP_SCAN_INTERVAL_DEFAULT   60
-#define BGP_IMPORT_INTERVAL_DEFAULT 15
-
 #define NEXTHOP_FAMILY(nexthop_len) ( \
   ((nexthop_len) ==  4 ||             \
    (nexthop_len) == 12 ? AF_INET :    \
@@ -40,15 +37,6 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 /* BGP nexthop cache value structure. */
 struct bgp_nexthop_cache
 {
-  /* This nexthop exists in IGP. */
-  u_char valid;
-
-  /* Nexthop is changed. */
-  u_char changed;
-
-  /* Nexthop is changed. */
-  u_char metricchanged;
-
   /* IGP route's metric. */
   u_int32_t metric;
 
@@ -58,26 +46,28 @@ struct bgp_nexthop_cache
   time_t last_update;
   u_int16_t flags;
 
-#define BGP_NEXTHOP_VALID (1 << 0)
-#define BGP_NEXTHOP_REGISTERED (1 << 1)
+#define BGP_NEXTHOP_VALID             (1 << 0)
+#define BGP_NEXTHOP_REGISTERED        (1 << 1)
+#define BGP_NEXTHOP_CONNECTED         (1 << 2)
+#define BGP_NEXTHOP_PEER_NOTIFIED     (1 << 3)
 
   u_int16_t change_flags;
 
-#define BGP_NEXTHOP_CHANGED (1 << 0)
-#define BGP_NEXTHOP_METRIC_CHANGED (1 << 1)
+#define BGP_NEXTHOP_CHANGED           (1 << 0)
+#define BGP_NEXTHOP_METRIC_CHANGED    (1 << 1)
+#define BGP_NEXTHOP_CONNECTED_CHANGED (1 << 2)
 
   struct bgp_node *node;
+  void *nht_info;		/* In BGP, peer session */
   LIST_HEAD(path_list, bgp_info) paths;
   unsigned int path_count;
 };
 
-extern void bgp_scan_init (void);
-extern void bgp_scan_finish (void);
 extern int bgp_nexthop_lookup (afi_t, struct peer *peer, struct bgp_info *,
 			int *, int *);
 extern void bgp_connected_add (struct connected *c);
 extern void bgp_connected_delete (struct connected *c);
-extern int bgp_multiaccess_check_v4 (struct in_addr, char *);
+extern int bgp_multiaccess_check_v4 (struct in_addr, struct peer *);
 extern int bgp_config_write_scan_time (struct vty *);
 extern int bgp_nexthop_onlink (afi_t, struct attr *);
 extern int bgp_nexthop_self (struct attr *);
@@ -89,4 +79,6 @@ extern void bnc_free(struct bgp_nexthop_cache *bnc);
 extern void bnc_nexthop_free(struct bgp_nexthop_cache *bnc);
 extern char *bnc_str(struct bgp_nexthop_cache *bnc, char *buf, int size);
 
+extern void bgp_scan_init (void);
+extern void bgp_scan_vty_init (void);
 #endif /* _QUAGGA_BGP_NEXTHOP_H */

bgpd/bgp_nht.c

@@ -39,6 +39,7 @@
 #include "bgpd/bgp_nexthop.h"
 #include "bgpd/bgp_debug.h"
 #include "bgpd/bgp_nht.h"
+#include "bgpd/bgp_fsm.h"
 
 extern struct zclient *zclient;
 extern struct bgp_table *bgp_nexthop_cache_table[AFI_MAX];
@@ -51,19 +52,15 @@ static void path_nh_map(struct bgp_info *path, struct bgp_nexthop_cache *bnc,
 			int keep);
 
 int
-bgp_find_nexthop (struct bgp_info *path, int *changed, int *metricchanged)
+bgp_find_nexthop (struct bgp_info *path, int connected)
 {
   struct bgp_nexthop_cache *bnc = path->nexthop;
 
   if (!bnc)
     return 0;
 
-  if (changed)
-    *changed = CHECK_FLAG(bnc->change_flags, BGP_NEXTHOP_CHANGED);
-
-  if (metricchanged)
-    *metricchanged = CHECK_FLAG(bnc->change_flags,
-				BGP_NEXTHOP_METRIC_CHANGED);
+  if (connected && !(CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED)))
+    return 0;
 
   return (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID));
 }
@@ -78,7 +75,7 @@ bgp_unlink_nexthop (struct bgp_info *path)
 
   path_nh_map(path, NULL, 0);
 
-  if (LIST_EMPTY(&(bnc->paths)))
+  if (LIST_EMPTY(&(bnc->paths)) && !bnc->nht_info)
     {
       if (BGP_DEBUG(nht, NHT))
 	{
@@ -94,15 +91,34 @@ bgp_unlink_nexthop (struct bgp_info *path)
 }
 
 int
-bgp_find_or_add_nexthop (afi_t afi, struct bgp_info *ri, int *changed,
-			 int *metricchanged)
+bgp_find_or_add_nexthop (afi_t afi, struct bgp_info *ri, struct peer *peer,
+			 int connected)
 {
   struct bgp_node *rn;
   struct bgp_nexthop_cache *bnc;
   struct prefix p;
 
-  if (make_prefix(afi, ri, &p) < 0)
-    return 1;
+  if (ri)
+    {
+      if (make_prefix(afi, ri, &p) < 0)
+	return 1;
+    }
+  else if (peer)
+    {
+      if (afi == AFI_IP)
+	{
+	  p.family = AF_INET;
+	  p.prefixlen = IPV4_MAX_BITLEN;
+	  p.u.prefix4 = peer->su.sin.sin_addr;
+	}
+      else if (afi == AFI_IP6)
+	{
+	  p.family = AF_INET6;
+	  p.prefixlen = IPV6_MAX_BITLEN;
+	  p.u.prefix6 = peer->su.sin6.sin6_addr;
+	}
+    }
+
   rn = bgp_node_get (bgp_nexthop_cache_table[afi], &p);
 
   if (!rn->info)
@@ -111,23 +127,27 @@ bgp_find_or_add_nexthop (afi_t afi, struct bgp_info *ri, int *changed,
       rn->info = bnc;
       bnc->node = rn;
       bgp_lock_node(rn);
-      register_nexthop(bnc);
+      if (connected)
+	SET_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED);
     }
+
   bnc = rn->info;
   bgp_unlock_node (rn);
-  path_nh_map(ri, bnc, 1);
 
-  if (changed)
-    *changed = CHECK_FLAG(bnc->change_flags, BGP_NEXTHOP_CHANGED);
+  if (!CHECK_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED))
+    register_nexthop(bnc);
 
-  if (metricchanged)
-    *metricchanged = CHECK_FLAG(bnc->change_flags,
-				BGP_NEXTHOP_METRIC_CHANGED);
+  if (ri)
+    {
+      path_nh_map(ri, bnc, 1);
 
-  if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID) && bnc->metric)
-    (bgp_info_extra_get(ri))->igpmetric = bnc->metric;
-  else if (ri->extra)
-    ri->extra->igpmetric = 0;
+      if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID) && bnc->metric)
+	(bgp_info_extra_get(ri))->igpmetric = bnc->metric;
+      else if (ri->extra)
+	ri->extra->igpmetric = 0;
+    }
+  else if (peer)
+    bnc->nht_info = (void *)peer;
 
   return (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID));
 }
@@ -269,6 +289,7 @@ bgp_parse_nexthop_update (void)
   else
     {
       bnc->flags &= ~BGP_NEXTHOP_VALID;
+      UNSET_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED);
       bnc_nexthop_free(bnc);
       bnc->nexthop = NULL;
     }
@@ -326,12 +347,21 @@ sendmsg_nexthop (struct bgp_nexthop_cache *bnc, int command)
 
   /* Check socket. */
   if (!zclient || zclient->sock < 0)
-    return;
+    {
+      zlog_debug("%s: Can't send NH register, Zebra client not established",
+		 __FUNCTION__);
+      return;
+    }
 
   p = &(bnc->node->p);
   s = zclient->obuf;
   stream_reset (s);
   zclient_create_header (s, command, VRF_DEFAULT);
+  if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED))
+    stream_putc(s, 1);
+  else
+    stream_putc(s, 0);
+
   stream_putw(s, PREFIX_FAMILY(p));
   stream_putc(s, p->prefixlen);
   switch (PREFIX_FAMILY(p))
@@ -339,11 +369,9 @@ sendmsg_nexthop (struct bgp_nexthop_cache *bnc, int command)
     case AF_INET:
       stream_put_in_addr (s, &p->u.prefix4);
       break;
-#ifdef HAVE_IPV6
     case AF_INET6:
       stream_put(s, &(p->u.prefix6), 16);
       break;
-#endif
     default:
       break;
     }
@@ -353,6 +381,11 @@ sendmsg_nexthop (struct bgp_nexthop_cache *bnc, int command)
   /* TBD: handle the failure */
   if (ret < 0)
     zlog_warn("sendmsg_nexthop: zclient_send_message() failed");
+
+  if (command == ZEBRA_NEXTHOP_REGISTER)
+    SET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
+  else if (command == ZEBRA_NEXTHOP_UNREGISTER)
+    UNSET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
   return;
 }
 
@@ -371,7 +404,6 @@ register_nexthop (struct bgp_nexthop_cache *bnc)
   if (bnc->flags & BGP_NEXTHOP_REGISTERED)
     return;
   sendmsg_nexthop(bnc, ZEBRA_NEXTHOP_REGISTER);
-  SET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
 }
 
 /**
@@ -389,7 +421,6 @@ unregister_nexthop (struct bgp_nexthop_cache *bnc)
     return;
 
   sendmsg_nexthop(bnc, ZEBRA_NEXTHOP_UNREGISTER);
-  UNSET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
 }
 
 /**
@@ -406,6 +437,7 @@ evaluate_paths (struct bgp_nexthop_cache *bnc)
   struct bgp_info *path;
   struct bgp *bgp = bgp_get_default();
   int afi;
+  struct peer *peer = (struct peer *)bnc->nht_info;
 
   LIST_FOREACH(path, &(bnc->paths), nh_thread)
     {
@@ -448,6 +480,15 @@ evaluate_paths (struct bgp_nexthop_cache *bnc)
 
       bgp_process(bgp, rn, afi, SAFI_UNICAST);
     }
+
+  if (peer && !CHECK_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED))
+    {
+      if (BGP_DEBUG(nht, NHT))
+	zlog_debug("%s: Updating peer (%s) status with NHT", __FUNCTION__, peer->host);
+      bgp_fsm_nht_update(peer, CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID));
+      SET_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED);
+    }
+
   RESET_FLAG(bnc->change_flags);
 }
 

bgpd/bgp_nht.h

@@ -31,12 +31,9 @@ extern void bgp_parse_nexthop_update(void);
  * bgp_find_nexthop() - lookup the nexthop cache table for the bnc object
  * ARGUMENTS:
  *   p - path for which the nexthop object is being looked up
- *   c - output variable that stores whether the nexthop object has changed
- *        since last time.
- *   m - output variable that stores whether the nexthop metric has changed
- *        since last time.
+ *   connected - True if NH MUST be a connected route
  */
-extern int bgp_find_nexthop(struct bgp_info *p, int *c, int *m);
+extern int bgp_find_nexthop(struct bgp_info *p, int connected);
 
 /**
  * bgp_find_or_add_nexthop() - lookup the nexthop cache table for the bnc
@@ -45,12 +42,11 @@ extern int bgp_find_nexthop(struct bgp_info *p, int *c, int *m);
  * ARGUMENTS:
  *   a - afi: AFI_IP or AF_IP6
  *   p - path for which the nexthop object is being looked up
- *   c - output variable that stores whether the nexthop object has changed
- *        since last time.
- *   m - output variable that stores whether the nexthop metric has changed
- *        since last time.
+ *   peer - The BGP peer associated with this NHT
+ *   connected - True if NH MUST be a connected route
  */
-extern int bgp_find_or_add_nexthop(afi_t a, struct bgp_info *p, int *c, int *m);
+extern int bgp_find_or_add_nexthop(afi_t a, struct bgp_info *p,
+				   struct peer *peer, int connected);
 
 /**
  * bgp_unlink_nexthop() - Unlink the nexthop object from the path structure.

bgpd/bgp_packet.c

@@ -103,8 +103,8 @@ bgp_packet_delete (struct peer *peer)
 }
 
 /* Check file descriptor whether connect is established. */
-static void
-bgp_connect_check (struct peer *peer)
+int
+bgp_connect_check (struct peer *peer, int change_state)
 {
   int status;
   socklen_t slen;
@@ -123,20 +123,23 @@ bgp_connect_check (struct peer *peer)
     {
       zlog (peer->log, LOG_INFO, "can't get sockopt for nonblocking connect");
       BGP_EVENT_ADD (peer, TCP_fatal_error);
-      return;
+      return -1;
     }      
 
   /* When status is 0 then TCP connection is established. */
   if (status == 0)
     {
       BGP_EVENT_ADD (peer, TCP_connection_open);
+      return 1;
     }
   else
     {
       if (BGP_DEBUG (events, EVENTS))
 	  plog_debug (peer->log, "%s [Event] Connect failed (%s)",
 		     peer->host, safe_strerror (errno));
-      BGP_EVENT_ADD (peer, TCP_connection_open_failed);
+      if (change_state)
+	BGP_EVENT_ADD (peer, TCP_connection_open_failed);
+      return 0;
     }
 }
 
@@ -715,7 +718,7 @@ bgp_write (struct thread *thread)
   /* For non-blocking IO check. */
   if (peer->status == Connect)
     {
-      bgp_connect_check (peer);
+      bgp_connect_check (peer, 1);
       return 0;
     }
 
@@ -2492,7 +2495,7 @@ bgp_read (struct thread *thread)
   /* For non-blocking IO check. */
   if (peer->status == Connect)
     {
-      bgp_connect_check (peer);
+      bgp_connect_check (peer, 1);
       goto done;
     }
   else

bgpd/bgp_packet.h

@@ -40,6 +40,7 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 /* Packet send and receive function prototypes. */
 extern int bgp_read (struct thread *);
 extern int bgp_write (struct thread *);
+extern int bgp_connect_check (struct peer *, int change_state);
 
 extern void bgp_keepalive_send (struct peer *);
 extern void bgp_open_send (struct peer *);

bgpd/bgp_route.c

@@ -55,7 +55,7 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 #include "bgpd/bgp_zebra.h"
 #include "bgpd/bgp_vty.h"
 #include "bgpd/bgp_mpath.h"
-#include "bgpd/bgp_nht.c"
+#include "bgpd/bgp_nht.h"
 
 /* Extern from bgp_dump.c */
 extern const char *bgp_origin_str[];
@@ -998,7 +998,7 @@ bgp_announce_check (struct bgp_info *ri, struct peer *peer, struct prefix *p,
 	   || (NEXTHOP_IS_V6 &&
                IN6_IS_ADDR_UNSPECIFIED(&attr->extra->mp_nexthop_global))
 	   || (peer->sort == BGP_PEER_EBGP
-	       && bgp_multiaccess_check_v4 (attr->nexthop, peer->host) == 0))
+               && (bgp_multiaccess_check_v4 (attr->nexthop, peer) == 0)))
     {
       /* Set IPv4 nexthop. */
       if (NEXTHOP_IS_V4)
@@ -2129,6 +2129,7 @@ bgp_update_main (struct peer *peer, struct prefix *p, struct attr *attr,
   struct bgp_info *new;
   const char *reason;
   char buf[SU_ADDRSTRLEN];
+  int connected = 0;
 
   memset (&new_attr, 0, sizeof(struct attr));
   memset (&new_extra, 0, sizeof(struct attr_extra));
@@ -2209,17 +2210,6 @@ bgp_update_main (struct peer *peer, struct prefix *p, struct attr *attr,
   /* IPv4 unicast next hop check.  */
   if (afi == AFI_IP && safi == SAFI_UNICAST)
     {
-      /* If the peer is EBGP and nexthop is not on connected route,
-	 discard it.  */
-      if (peer->sort == BGP_PEER_EBGP && peer->ttl == 1
-	  && ! bgp_nexthop_onlink (afi, &new_attr)
-	  && ! CHECK_FLAG (peer->flags, PEER_FLAG_DISABLE_CONNECTED_CHECK))
-	{
-	  reason = "non-connected next-hop;";
-	  bgp_attr_flush (&new_attr);
-	  goto filtered;
-	}
-
       /* Next hop must not be 0.0.0.0 nor Class D/E address. Next hop
 	 must not be my own address.  */
       if (new_attr.nexthop.s_addr == 0
@@ -2347,20 +2337,29 @@ bgp_update_main (struct peer *peer, struct prefix *p, struct attr *attr,
 	}
 
       /* Nexthop reachability check. */
-      if ((afi == AFI_IP || afi == AFI_IP6)
-	  && safi == SAFI_UNICAST 
-	  && (peer->sort == BGP_PEER_IBGP
-              || peer->sort == BGP_PEER_CONFED
-	      || (peer->sort == BGP_PEER_EBGP && peer->ttl != 1)
-	      || CHECK_FLAG (peer->flags, PEER_FLAG_DISABLE_CONNECTED_CHECK)))
+      if ((afi == AFI_IP || afi == AFI_IP6) && safi == SAFI_UNICAST)
 	{
-	  if (bgp_find_or_add_nexthop (afi, ri, NULL, NULL))
+	  if (peer->sort == BGP_PEER_EBGP && peer->ttl == 1 &&
+	      ! CHECK_FLAG (peer->flags, PEER_FLAG_DISABLE_CONNECTED_CHECK))
+	    connected = 1;
+	  else
+	    connected = 0;
+
+	  if (bgp_find_or_add_nexthop (afi, ri, NULL, connected))
 	    bgp_info_set_flag (rn, ri, BGP_INFO_VALID);
 	  else
-	    bgp_info_unset_flag (rn, ri, BGP_INFO_VALID);
+	    {
+	      if (BGP_DEBUG(nht, NHT))
+		{
+		  char buf1[INET6_ADDRSTRLEN];
+		  inet_ntop(AF_INET, (const void *)&attr_new->nexthop, buf1, INET6_ADDRSTRLEN);
+		  zlog_debug("%s(%s): NH unresolved", __FUNCTION__, buf1);
+		}
+	      bgp_info_unset_flag (rn, ri, BGP_INFO_VALID);
+	    }
 	}
       else
-        bgp_info_set_flag (rn, ri, BGP_INFO_VALID);
+	bgp_info_set_flag (rn, ri, BGP_INFO_VALID);
 
       bgp_attr_flush (&new_attr);
 
@@ -2390,17 +2389,26 @@ bgp_update_main (struct peer *peer, struct prefix *p, struct attr *attr,
     memcpy ((bgp_info_extra_get (new))->tag, tag, 3);
 
   /* Nexthop reachability check. */
-  if ((afi == AFI_IP || afi == AFI_IP6)
-      && safi == SAFI_UNICAST
-      && (peer->sort == BGP_PEER_IBGP
-          || peer->sort == BGP_PEER_CONFED
-	  || (peer->sort == BGP_PEER_EBGP && peer->ttl != 1)
-	  || CHECK_FLAG (peer->flags, PEER_FLAG_DISABLE_CONNECTED_CHECK)))
-    {
-      if (bgp_find_or_add_nexthop (afi, new, NULL, NULL))
+  if ((afi == AFI_IP || afi == AFI_IP6) && safi == SAFI_UNICAST)
+    {
+      if (peer->sort == BGP_PEER_EBGP && peer->ttl == 1 &&
+	  ! CHECK_FLAG (peer->flags, PEER_FLAG_DISABLE_CONNECTED_CHECK))
+	connected = 1;
+      else
+	connected = 0;
+
+      if (bgp_find_or_add_nexthop (afi, new, NULL, connected))
 	bgp_info_set_flag (rn, new, BGP_INFO_VALID);
       else
-        bgp_info_unset_flag (rn, new, BGP_INFO_VALID);
+	{
+	  if (BGP_DEBUG(nht, NHT))
+	    {
+	      char buf1[INET6_ADDRSTRLEN];
+	      inet_ntop(AF_INET, (const void *)&attr_new->nexthop, buf1, INET6_ADDRSTRLEN);
+	      zlog_debug("%s(%s): NH unresolved", __FUNCTION__, buf1);
+	    }
+	  bgp_info_unset_flag (rn, new, BGP_INFO_VALID);
+	}
     }
   else
     bgp_info_set_flag (rn, new, BGP_INFO_VALID);
@@ -3532,6 +3540,23 @@ bgp_static_update_rsclient (struct peer *rsclient, struct prefix *p,
           ri->attr = attr_new;
           ri->uptime = bgp_clock ();
 
+	  /* Nexthop reachability check. */
+	  if (bgp_flag_check (bgp, BGP_FLAG_IMPORT_CHECK))
+	    {
+	      if (bgp_find_or_add_nexthop (afi, ri, NULL, 0))
+		bgp_info_set_flag (rn, ri, BGP_INFO_VALID);
+	      else
+		{
+		  if (BGP_DEBUG(nht, NHT))
+		    {
+		      char buf1[INET6_ADDRSTRLEN];
+		      inet_ntop(AF_INET, (const void *)&attr_new->nexthop,
+				buf1, INET6_ADDRSTRLEN);
+		      zlog_debug("%s(%s): NH unresolved", __FUNCTION__, buf1);
+		    }
+		  bgp_info_unset_flag (rn, ri, BGP_INFO_VALID);
+		}
+	    }
           /* Process change. */
           bgp_process (bgp, rn, afi, safi);
           bgp_unlock_node (rn);
@@ -3544,7 +3569,25 @@ bgp_static_update_rsclient (struct peer *rsclient, struct prefix *p,
   /* Make new BGP info. */
   new = info_make(ZEBRA_ROUTE_BGP, BGP_ROUTE_STATIC, bgp->peer_self,
 		  attr_new, rn);
-  SET_FLAG (new->flags, BGP_INFO_VALID);
+  /* Nexthop reachability check. */
+  if (bgp_flag_check (bgp, BGP_FLAG_IMPORT_CHECK))
+    {
+      if (bgp_find_or_add_nexthop (afi, new, NULL, 0))
+	bgp_info_set_flag (rn, new, BGP_INFO_VALID);
+      else
+	{
+	  if (BGP_DEBUG(nht, NHT))
+	    {
+	      char buf1[INET6_ADDRSTRLEN];
+	      inet_ntop(AF_INET, (const void *)&attr_new->nexthop,
+			buf1, INET6_ADDRSTRLEN);
+	      zlog_debug("%s(%s): NH unresolved", __FUNCTION__, buf1);
+	    }
+	  bgp_info_unset_flag (rn, new, BGP_INFO_VALID);
+	}
+    }
+  else
+    bgp_info_set_flag (rn, new, BGP_INFO_VALID);
 
   /* Register new BGP information. */
   bgp_info_add (rn, new);
@@ -3562,7 +3605,7 @@ bgp_static_update_rsclient (struct peer *rsclient, struct prefix *p,
 
 static void
 bgp_static_update_main (struct bgp *bgp, struct prefix *p,
-		   struct bgp_static *bgp_static, afi_t afi, safi_t safi)
+			struct bgp_static *bgp_static, afi_t afi, safi_t safi)
 {
   struct bgp_node *rn;
   struct bgp_info *ri;
@@ -3646,6 +3689,23 @@ bgp_static_update_main (struct bgp *bgp, struct prefix *p,
 	  ri->attr = attr_new;
 	  ri->uptime = bgp_clock ();
 
+	  /* Nexthop reachability check. */
+	  if (bgp_flag_check (bgp, BGP_FLAG_IMPORT_CHECK))
+	    {
+	      if (bgp_find_or_add_nexthop (afi, ri, NULL, 0))
+		bgp_info_set_flag (rn, ri, BGP_INFO_VALID);
+	      else
+		{
+		  if (BGP_DEBUG(nht, NHT))
+		    {
+		      char buf1[INET6_ADDRSTRLEN];
+		      inet_ntop(AF_INET, (const void *)&attr_new->nexthop,
+				buf1, INET6_ADDRSTRLEN);
+		      zlog_debug("%s(%s): NH unresolved", __FUNCTION__, buf1);
+		    }
+		  bgp_info_unset_flag (rn, ri, BGP_INFO_VALID);
+		}
+	    }
 	  /* Process change. */
 	  bgp_aggregate_increment (bgp, p, ri, afi, safi);
 	  bgp_process (bgp, rn, afi, safi);
@@ -3659,7 +3719,25 @@ bgp_static_update_main (struct bgp *bgp, struct prefix *p,
   /* Make new BGP info. */
   new = info_make(ZEBRA_ROUTE_BGP, BGP_ROUTE_STATIC, bgp->peer_self, attr_new,
 		  rn);
-  SET_FLAG (new->flags, BGP_INFO_VALID);
+  /* Nexthop reachability check. */
+  if (bgp_flag_check (bgp, BGP_FLAG_IMPORT_CHECK))
+    {
+      if (bgp_find_or_add_nexthop (afi, new, NULL, 0))
+	bgp_info_set_flag (rn, new, BGP_INFO_VALID);
+      else
+	{
+	  if (BGP_DEBUG(nht, NHT))
+	    {
+	      char buf1[INET6_ADDRSTRLEN];
+	      inet_ntop(AF_INET, (const void *)&attr_new->nexthop, buf1,
+			INET6_ADDRSTRLEN);
+	      zlog_debug("%s(%s): NH unresolved", __FUNCTION__, buf1);
+	    }
+	  bgp_info_unset_flag (rn, new, BGP_INFO_VALID);
+	}
+    }
+  else
+    bgp_info_set_flag (rn, new, BGP_INFO_VALID);
 
   /* Aggregate address increment. */
   bgp_aggregate_increment (bgp, p, new, afi, safi);
@@ -3720,6 +3798,7 @@ bgp_static_withdraw (struct bgp *bgp, struct prefix *p, afi_t afi,
   if (ri)
     {
       bgp_aggregate_decrement (bgp, p, ri, afi, safi);
+      bgp_unlink_nexthop(ri);
       bgp_info_delete (rn, ri);
       bgp_process (bgp, rn, afi, safi);
     }
@@ -3978,17 +4057,12 @@ bgp_static_set (struct vty *vty, struct bgp *bgp, const char *ip_str,
       rn->info = bgp_static;
     }
 
-  /* If BGP scan is not enabled, we should install this route here.  */
-  if (! bgp_flag_check (bgp, BGP_FLAG_IMPORT_CHECK))
-    {
-      bgp_static->valid = 1;
-
-      if (need_update)
-	bgp_static_withdraw (bgp, &p, afi, safi);
+  bgp_static->valid = 1;
+  if (need_update)
+    bgp_static_withdraw (bgp, &p, afi, safi);
 
-      if (! bgp_static->backdoor)
-	bgp_static_update (bgp, &p, bgp_static, afi, safi);
-    }
+  if (! bgp_static->backdoor)
+    bgp_static_update (bgp, &p, bgp_static, afi, safi);
 
   return CMD_SUCCESS;
 }

bgpd/bgpd.c

@@ -61,6 +61,7 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 #include "bgpd/bgp_network.h"
 #include "bgpd/bgp_vty.h"
 #include "bgpd/bgp_mpath.h"
+#include "bgpd/bgp_nht.h"
 #ifdef HAVE_SNMP
 #include "bgpd/bgp_snmp.h"
 #endif /* HAVE_SNMP */
@@ -4564,24 +4565,33 @@ peer_maximum_prefix_set (struct peer *peer, afi_t afi, safi_t safi,
   else
     UNSET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_MAX_PREFIX_WARNING);
 
-  if (! CHECK_FLAG (peer->sflags, PEER_STATUS_GROUP))
-    return 0;
-
-  group = peer->group;
-  for (ALL_LIST_ELEMENTS (group->peer, node, nnode, peer))
+  if (CHECK_FLAG (peer->sflags, PEER_STATUS_GROUP))
     {
-      if (! peer->af_group[afi][safi])
-	continue;
+      group = peer->group;
+      for (ALL_LIST_ELEMENTS (group->peer, node, nnode, peer))
+	{
+	  if (! peer->af_group[afi][safi])
+	    continue;
 
-      SET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_MAX_PREFIX);
-      peer->pmax[afi][safi] = max;
-      peer->pmax_threshold[afi][safi] = threshold;
-      peer->pmax_restart[afi][safi] = restart;
-      if (warning)
-	SET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_MAX_PREFIX_WARNING);
-      else
-	UNSET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_MAX_PREFIX_WARNING);
+	  SET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_MAX_PREFIX);
+	  peer->pmax[afi][safi] = max;
+	  peer->pmax_threshold[afi][safi] = threshold;
+	  peer->pmax_restart[afi][safi] = restart;
+	  if (warning)
+	    SET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_MAX_PREFIX_WARNING);
+	  else
+	    UNSET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_MAX_PREFIX_WARNING);
+
+	  if ((peer->status == Established) && (peer->afc[afi][safi]))
+	    bgp_maximum_prefix_overflow (peer, afi, safi, 1);
+	}
+    }
+  else
+    {
+      if ((peer->status == Established) && (peer->afc[afi][safi]))
+	bgp_maximum_prefix_overflow (peer, afi, safi, 1);
     }
+
   return 0;
 }
 
@@ -5572,9 +5582,6 @@ bgp_config_write (struct vty *vty)
       if (bgp_flag_check (bgp, BGP_FLAG_IMPORT_CHECK))
 	vty_out (vty, " bgp network import-check%s", VTY_NEWLINE);
 
-      /* BGP scan interval. */
-      bgp_config_write_scan_time (vty);
-
       /* BGP flag dampening. */
       if (CHECK_FLAG (bgp->af_flags[AFI_IP][SAFI_UNICAST],
 	  BGP_CONFIG_DAMPENING))
@@ -5660,12 +5667,16 @@ bgp_master_init (void)
 void
 bgp_init (void)
 {
-  /* BGP VTY commands installation.  */
-  bgp_vty_init ();
+
+  /* allocates some vital data structures used by peer commands in vty_init */
+  bgp_scan_init ();
 
   /* Init zebra. */
   bgp_zebra_init (bm->master);
 
+  /* BGP VTY commands installation.  */
+  bgp_vty_init ();
+
   /* BGP inits. */
   bgp_attr_init ();
   bgp_debug_init ();
@@ -5673,7 +5684,7 @@ bgp_init (void)
   bgp_route_init ();
   bgp_route_map_init ();
   bgp_address_init ();
-  bgp_scan_init ();
+  bgp_scan_vty_init();
   bgp_mplsvpn_init ();
   bgp_encap_init ();
 

bgpd/bgpd.h

@@ -997,4 +997,5 @@ extern int peer_clear_soft (struct peer *, afi_t, safi_t, enum bgp_clear_type);
 extern int peer_ttl_security_hops_set (struct peer *, int);
 extern int peer_ttl_security_hops_unset (struct peer *);
 
+extern void bgp_scan_finish (void);
 #endif /* _QUAGGA_BGPD_H */

zebra/zebra_rnh.c

@@ -212,7 +212,8 @@ zebra_evaluate_rnh_table (vrf_id_t vrfid, int family)
     {
       if (!nrn->info)
 	  continue;
-
+      
+      rnh = nrn->info;
       prn = route_node_match(ptable, &nrn->p);
       if (!prn)
 	rib = NULL;
@@ -223,11 +224,18 @@ zebra_evaluate_rnh_table (vrf_id_t vrfid, int family)
 	      if (CHECK_FLAG (rib->status, RIB_ENTRY_REMOVED))
 		continue;
 	      if (CHECK_FLAG (rib->flags, ZEBRA_FLAG_SELECTED))
-		break;
+		{
+		  if (CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED))
+		    {
+		      if (rib->type == ZEBRA_ROUTE_CONNECT)
+			break;
+		    }
+		  else
+		    break;
+		}
 	    }
 	}
 
-      rnh = nrn->info;
       if (compare_state(rib, rnh->state))
 	{
 	  if (IS_ZEBRA_DEBUG_NHT)
@@ -598,7 +606,9 @@ print_rnh (struct route_node *rn, struct vty *vty)
 	print_nh(nexthop, vty);
     }
   else
-    vty_out(vty, " unresolved%s", VTY_NEWLINE);
+    vty_out(vty, " unresolved%s%s",
+	    CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED) ? "(Connected)" : "",
+	    VTY_NEWLINE);
 
   vty_out(vty, " Client list:");
   for (ALL_LIST_ELEMENTS_RO(rnh->client_list, node, client))

zebra/zebra_rnh.h

@@ -30,6 +30,7 @@
 struct rnh
 {
   u_char flags;
+#define ZEBRA_NHT_CONNECTED  	0x1
   struct rib *state;
   struct list *client_list;
   struct route_node *node;

zebra/zserv.c

@@ -748,6 +748,7 @@ zserv_nexthop_register (struct zserv *client, int sock, u_short length, vrf_id_t
   struct stream *s;
   struct prefix p;
   u_short l = 0;
+  u_char connected;
 
   if (IS_ZEBRA_DEBUG_NHT)
     zlog_debug("nexthop_register msg from client %s: length=%d\n",
@@ -757,14 +758,19 @@ zserv_nexthop_register (struct zserv *client, int sock, u_short length, vrf_id_t
 
   while (l < length)
     {
+      connected = stream_getc(s);
       p.family = stream_getw(s);
       p.prefixlen = stream_getc(s);
-      l += 3;
+      l += 4;
       stream_get(&p.u.prefix, s, PSIZE(p.prefixlen));
       l += PSIZE(p.prefixlen);
       rnh = zebra_add_rnh(&p, 0);
 
       client->nh_reg_time = quagga_time(NULL);
+      
+      if (connected)
+	SET_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED);
+
       zebra_add_rnh_client(rnh, client, vrf_id);
     }
   zebra_evaluate_rnh_table(0, AF_INET);
@@ -789,9 +795,10 @@ zserv_nexthop_unregister (struct zserv *client, int sock, u_short length)
 
   while (l < length)
     {
+      (void)stream_getc(s);
       p.family = stream_getw(s);
       p.prefixlen = stream_getc(s);
-      l += 3;
+      l += 4;
       stream_get(&p.u.prefix, s, PSIZE(p.prefixlen));
       l += PSIZE(p.prefixlen);
       rnh = zebra_lookup_rnh(&p, 0);