Even better nexthop delete behaviour. Do not delete nexthop if they are used

by filter sets or if the nexthop is currently looked up. With this the
"nexthop_update: non-existent nexthop" warning should be history. OK henning@

3 files changed, 33 insertions, 15 deletions

diff --git a/usr.sbin/bgpd/rde.h b/usr.sbin/bgpd/rde.h
index bb3c0e9d6ce..f3cdb01a0ba 100644
--- a/usr.sbin/bgpd/rde.h
+++ b/usr.sbin/bgpd/rde.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde.h,v 1.94 2006/05/28 22:07:54 claudio Exp $ */
+/*	$OpenBSD: rde.h,v 1.95 2006/05/28 23:24:15 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Claudio Jeker <claudio@openbsd.org> and
@@ -335,6 +335,7 @@ void		 nexthop_modify(struct rde_aspath *, struct bgpd_addr *,
 		     enum action_types, sa_family_t);
 void		 nexthop_link(struct rde_aspath *);
 void		 nexthop_unlink(struct rde_aspath *);
+int		 nexthop_delete(struct nexthop *);
 void		 nexthop_update(struct kroute_nexthop *);
 struct nexthop	*nexthop_get(struct bgpd_addr *);
 int		 nexthop_compare(struct nexthop *, struct nexthop *);
diff --git a/usr.sbin/bgpd/rde_filter.c b/usr.sbin/bgpd/rde_filter.c
index 12eaa717876..97d4b992a32 100644
--- a/usr.sbin/bgpd/rde_filter.c
+++ b/usr.sbin/bgpd/rde_filter.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde_filter.c,v 1.49 2006/05/28 22:07:54 claudio Exp $ */
+/*	$OpenBSD: rde_filter.c,v 1.50 2006/05/28 23:24:15 claudio Exp $ */
 
 /*
  * Copyright (c) 2004 Claudio Jeker <claudio@openbsd.org>
@@ -439,13 +439,8 @@ filterset_free(struct filter_set_head *sh)
 		else if (s->type == ACTION_SET_NEXTHOP &&
 		    bgpd_process == PROC_RDE) {
 			nh = nexthop_get(&s->action.nexthop);
-			if (--nh->refcnt <= 0 && LIST_EMPTY(&nh->path_h)) {
-				LIST_REMOVE(nh, nexthop_l);
-				rde_send_nexthop(&nh->exit_nexthop, 0);
-
-				rdemem.nexthop_cnt--;
-				free(nh);
-			}
+			--nh->refcnt;
+			(void)nexthop_delete(nh);
 		}
 		free(s);
 	}
diff --git a/usr.sbin/bgpd/rde_rib.c b/usr.sbin/bgpd/rde_rib.c
index a566c0288ad..30dc4256c1b 100644
--- a/usr.sbin/bgpd/rde_rib.c
+++ b/usr.sbin/bgpd/rde_rib.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde_rib.c,v 1.86 2006/05/28 22:07:54 claudio Exp $ */
+/*	$OpenBSD: rde_rib.c,v 1.87 2006/05/28 23:24:15 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Claudio Jeker <claudio@openbsd.org>
@@ -801,10 +801,18 @@ void
 nexthop_shutdown(void)
 {
 	u_int32_t		 i;
-
-	for (i = 0; i <= nexthoptable.nexthop_hashmask; i++)
+	struct nexthop		*nh, *nnh;
+
+	for (i = 0; i <= nexthoptable.nexthop_hashmask; i++) {
+		for(nh = LIST_FIRST(&nexthoptable.nexthop_hashtbl[i]);
+		    nh != NULL; nh = nnh) {
+			nnh = LIST_NEXT(nh, nexthop_l);
+			nh->state = NEXTHOP_UNREACH;
+			(void)nexthop_delete(nh);
+		}
 		if (!LIST_EMPTY(&nexthoptable.nexthop_hashtbl[i]))
 			log_warnx("nexthop_shutdown: non-free table");
+	}
 
 	free(nexthoptable.nexthop_hashtbl);
 }
@@ -817,7 +825,8 @@ nexthop_update(struct kroute_nexthop *msg)
 
 	nh = nexthop_lookup(&msg->nexthop);
 	if (nh == NULL) {
-		log_warnx("nexthop_update: non-existent nexthop");
+		log_warnx("nexthop_update: non-existent nexthop %s",
+		    log_addr(&msg->nexthop));
 		return;
 	}
 
@@ -826,6 +835,10 @@ nexthop_update(struct kroute_nexthop *msg)
 	else
 		nh->state = NEXTHOP_UNREACH;
 
+	if (nexthop_delete(nh))
+		/* nexthop no longer used */
+		return;
+
 	if (msg->connected) {
 		nh->flags |= NEXTHOP_CONNECTED;
 		memcpy(&nh->true_nexthop, &nh->exit_nexthop,
@@ -918,8 +931,15 @@ nexthop_unlink(struct rde_aspath *asp)
 	nh = asp->nexthop;
 	asp->nexthop = NULL;
 
-	if (nh->refcnt > 0)
-		return;
+	(void)nexthop_delete(nh);
+}
+
+int
+nexthop_delete(struct nexthop *nh)
+{
+	/* either pinned or in a state where it may not be deleted */
+	if (nh->refcnt > 0 || nh->state == NEXTHOP_LOOKUP)
+		return (0);
 
 	if (LIST_EMPTY(&nh->path_h)) {
 		LIST_REMOVE(nh, nexthop_l);
@@ -927,7 +947,9 @@ nexthop_unlink(struct rde_aspath *asp)
 
 		rdemem.nexthop_cnt--;
 		free(nh);
+		return (1);
 	}
+	return (0);
 }
 
 struct nexthop *