Simplify evaluation process. Instead of checking the reachability of a prefix

at many different places do it once. This simplifies the logic and makes it
easier to extend it for upcomming Adj-RIB-In addition. OK Henning.

3 files changed, 19 insertions, 24 deletions

diff --git a/usr.sbin/bgpd/rde.c b/usr.sbin/bgpd/rde.c
index 00498b8765b..3d42f8b1407 100644
--- a/usr.sbin/bgpd/rde.c
+++ b/usr.sbin/bgpd/rde.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde.c,v 1.191 2006/01/12 14:05:13 claudio Exp $ */
+/*	$OpenBSD: rde.c,v 1.192 2006/01/13 13:04:33 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -1550,19 +1550,14 @@ rde_send_kroute(struct prefix *new, struct prefix *old)
 	enum imsg_type		 type;
 
 	/*
-	 * If old is != NULL we know it was active and should be removed.
-	 * On the other hand new may be UNREACH and then we should not
-	 * generate an update.
+	 * Make sure that self announce prefixes are not commited to the
+	 * FIB. If both prefixes are unreachable no update is needed.
 	 */
 	if ((old == NULL || old->aspath->flags & F_PREFIX_ANNOUNCED) &&
-	    (new == NULL || new->aspath->nexthop == NULL ||
-	    new->aspath->nexthop->state != NEXTHOP_REACH ||
-	    new->aspath->flags & F_PREFIX_ANNOUNCED))
+	    (new == NULL || new->aspath->flags & F_PREFIX_ANNOUNCED))
 		return;
 
-	if (new == NULL || new->aspath->nexthop == NULL ||
-	    new->aspath->nexthop->state != NEXTHOP_REACH ||
-	    new->aspath->flags & F_PREFIX_ANNOUNCED) {
+	if (new == NULL || new->aspath->flags & F_PREFIX_ANNOUNCED) {
 		type = IMSG_KROUTE_DELETE;
 		p = old;
 	} else {
@@ -1747,11 +1742,10 @@ rde_generate_updates(struct prefix *new, struct prefix *old)
 
 	/*
 	 * If old is != NULL we know it was active and should be removed.
-	 * On the other hand new may be UNREACH and then we should not
+	 * If new is != NULL we know it is reachable and then we should 
 	 * generate an update.
 	 */
-	if (old == NULL && (new == NULL || (new->aspath->nexthop != NULL &&
-	    new->aspath->nexthop->state != NEXTHOP_REACH)))
+	if (old == NULL && new == NULL)
 		return;
 
 	LIST_FOREACH(peer, &peerlist, peer_l) {
diff --git a/usr.sbin/bgpd/rde_decide.c b/usr.sbin/bgpd/rde_decide.c
index a50b09717f4..e4895538c07 100644
--- a/usr.sbin/bgpd/rde_decide.c
+++ b/usr.sbin/bgpd/rde_decide.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde_decide.c,v 1.44 2006/01/04 12:50:31 claudio Exp $ */
+/*	$OpenBSD: rde_decide.c,v 1.45 2006/01/13 13:04:33 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Claudio Jeker <claudio@openbsd.org>
@@ -230,7 +230,13 @@ prefix_evaluate(struct prefix *p, struct pt_entry *pte)
 				}
 		}
 	}
+
 	xp = LIST_FIRST(&pte->prefix_h);
+	if (xp == NULL || (xp->aspath->nexthop != NULL &&
+	    xp->aspath->nexthop->state != NEXTHOP_REACH))
+		/* xp is ineligible */
+		xp = NULL;
+
 	if (pte->active != xp) {
 		/* need to generate an update */
 		if (pte->active != NULL)
@@ -246,12 +252,8 @@ prefix_evaluate(struct prefix *p, struct pt_entry *pte)
 		rde_generate_updates(xp, pte->active);
 		rde_send_kroute(xp, pte->active);
 
-		if (xp == NULL || (xp->aspath->nexthop != NULL &&
-		    xp->aspath->nexthop->state != NEXTHOP_REACH))
-			pte->active = NULL;
-		else {
-			pte->active = xp;
-			pte->active->aspath->active_cnt++;
-		}
+		pte->active = xp;
+		if (xp != NULL)
+			xp->aspath->active_cnt++;
 	}
 }
diff --git a/usr.sbin/bgpd/rde_update.c b/usr.sbin/bgpd/rde_update.c
index 9593430bd64..f78d33762da 100644
--- a/usr.sbin/bgpd/rde_update.c
+++ b/usr.sbin/bgpd/rde_update.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde_update.c,v 1.48 2006/01/12 14:05:13 claudio Exp $ */
+/*	$OpenBSD: rde_update.c,v 1.49 2006/01/13 13:04:33 claudio Exp $ */
 
 /*
  * Copyright (c) 2004 Claudio Jeker <claudio@openbsd.org>
@@ -406,8 +406,7 @@ up_generate_updates(struct filter_head *rules, struct rde_peer *peer,
 	if (peer->state != PEER_UP)
 		return;
 
-	if (new == NULL || (new->aspath->nexthop != NULL &&
-	    new->aspath->nexthop->state != NEXTHOP_REACH)) {
+	if (new == NULL) {
 		if (up_test_update(peer, old) != 1)
 			return;