From: Claudio Jeker <cjeker@diehard.n-r-g.com>
Subject: bgpd: remove nhflags and dmetric for adj-rib-out
To: tech@openbsd.org
Date: Thu, 20 Nov 2025 14:50:54 +0100

In the Adj-RIB-Out dmetric has no meaning (by default there is only one
path). Also nhflags are not needed any more since the nexthop selection
happens right before addition to the Adj-RIB-Out in up_prep_adjout().

-- 
:wq Claudio

? obj
Index: rde.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde.c,v
diff -u -p -r1.668 rde.c
--- rde.c	20 Nov 2025 13:46:22 -0000	1.668
+++ rde.c	20 Nov 2025 13:47:46 -0000
@@ -2994,7 +2994,6 @@ rde_dump_adjout_as(struct prefix_adjout 
 	rib.prefixlen = p->pt->prefixlen;
 	rib.origin = asp->origin;
 	/* roa and aspa vstate skipped, they don't matter in adj-rib-out */
-	rib.dmetric = p->dmetric;
 	rib.flags = 0;
 	rib.flags |= F_PREF_ELIGIBLE;
 	if (!peer->conf.ebgp)
Index: rde.h
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde.h,v
diff -u -p -r1.323 rde.h
--- rde.h	20 Nov 2025 13:46:22 -0000	1.323
+++ rde.h	20 Nov 2025 13:47:46 -0000
@@ -314,8 +314,6 @@ struct prefix_adjout {
 	uint32_t			 path_id_tx;
 	uint8_t			 	 flags;
 	uint8_t				 validation_state;
-	uint8_t				 nhflags;
-	int8_t				 dmetric;	/* decision metric */
 };
 #define	PREFIX_ADJOUT_FLAG_WITHDRAW	0x01	/* enqueued on withdraw queue */
 #define	PREFIX_ADJOUT_FLAG_UPDATE	0x02	/* enqueued on update queue */
@@ -770,12 +768,6 @@ static inline struct nexthop *
 prefix_adjout_nexthop(struct prefix_adjout *p)
 {
 	return (p->nexthop);
-}
-
-static inline uint8_t
-prefix_adjout_nhflags(struct prefix_adjout *p)
-{
-	return (p->nhflags & NEXTHOP_MASK);
 }
 
 /* rde_update.c */
Index: rde_adjout.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde_adjout.c,v
diff -u -p -r1.5 rde_adjout.c
--- rde_adjout.c	20 Nov 2025 13:46:22 -0000	1.5
+++ rde_adjout.c	20 Nov 2025 13:47:46 -0000
@@ -63,7 +63,7 @@ prefix_is_dead(struct prefix_adjout *p)
 static void	 prefix_adjout_link(struct prefix_adjout *, struct pt_entry *,
 		    struct rde_peer *, uint32_t, uint32_t,
 		    struct rde_aspath *, struct rde_community *,
-		    struct nexthop *, uint8_t, uint8_t);
+		    struct nexthop *, uint8_t);
 static void	 prefix_adjout_unlink(struct prefix_adjout *);
 
 static struct prefix_adjout	*prefix_adjout_alloc(void);
@@ -101,8 +101,6 @@ prefix_cmp(struct prefix_adjout *a, stru
 		return (a->communities > b->communities ? 1 : -1);
 	if (a->nexthop != b->nexthop)
 		return (a->nexthop > b->nexthop ? 1 : -1);
-	if (a->nhflags != b->nhflags)
-		return (a->nhflags > b->nhflags ? 1 : -1);
 	return prefix_index_cmp(a, b);
 }
 
@@ -249,7 +247,6 @@ prefix_adjout_update(struct prefix_adjou
 		 * paths.
 		 */
 		if (p->path_id_tx == path_id_tx &&
-		    prefix_adjout_nhflags(p) == state->nhflags &&
 		    prefix_adjout_nexthop(p) == state->nexthop &&
 		    communities_equal(&state->communities,
 		    prefix_adjout_communities(p)) &&
@@ -296,7 +293,7 @@ prefix_adjout_update(struct prefix_adjou
 	}
 
 	prefix_adjout_link(p, p->pt, peer, 0, p->path_id_tx, asp, comm,
-	    state->nexthop, state->nhflags, state->vstate);
+	    state->nexthop, state->vstate);
 	peer->stats.prefix_out_cnt++;
 
 	if (p->flags & PREFIX_ADJOUT_FLAG_MASK)
@@ -572,7 +569,7 @@ static void
 prefix_adjout_link(struct prefix_adjout *p, struct pt_entry *pt,
     struct rde_peer *peer, uint32_t path_id, uint32_t path_id_tx,
     struct rde_aspath *asp, struct rde_community *comm,
-    struct nexthop *nexthop, uint8_t nhflags, uint8_t vstate)
+    struct nexthop *nexthop, uint8_t vstate)
 {
 	p->aspath = path_ref(asp);
 	p->communities = communities_ref(comm);
@@ -582,9 +579,6 @@ prefix_adjout_link(struct prefix_adjout 
 	p->path_id_tx = path_id_tx;
 	p->validation_state = vstate;
 	p->nexthop = nexthop_ref(nexthop);
-	p->nhflags = nhflags;
-	/* All nexthops are valid in Adj-RIB-Out */
-	p->nhflags |= NEXTHOP_VALID;
 	p->lastchange = getmonotime();
 }
 
@@ -598,7 +592,6 @@ prefix_adjout_unlink(struct prefix_adjou
 	/* remove nexthop ref ... */
 	nexthop_unref(p->nexthop);
 	p->nexthop = NULL;
-	p->nhflags = 0;
 	/* ... communities ... */
 	communities_unref(p->communities);
 	p->communities = NULL;
Index: rde_update.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde_update.c,v
diff -u -p -r1.182 rde_update.c
--- rde_update.c	20 Nov 2025 13:46:22 -0000	1.182
+++ rde_update.c	20 Nov 2025 13:47:46 -0000
@@ -855,7 +855,6 @@ up_dump_prefix(struct ibuf *buf, struct 
 		    np->aspath != p->aspath ||
 		    np->communities != p->communities ||
 		    np->nexthop != p->nexthop ||
-		    np->nhflags != p->nhflags ||
 		    (np->flags & PREFIX_ADJOUT_FLAG_EOR))
 			done = 1;