From: Claudio Jeker <cjeker@diehard.n-r-g.com>
Subject: bgpd: various little cleanup and prep steps
To: tech@openbsd.org
Date: Tue, 16 Dec 2025 11:49:46 +0100

Cleanup a few things:

- use for loops in rde_dump_ctx_new() instead of a while loop.
- in insert_community() use sizeof(*new) instead of sizeof(struct ...)
- add a struct pt_entry *pte argument to adjout_prefix_next() and
  adjout_prefix_withdraw()
- extend the prefix / pt API with pt_first, pt_next and pt_get_next.
  The first to functions can be used to build iterators and pt_get_next
  is like pt_get but uses RB_NFIND instead of RB_FIND and therefor finds
  the next matching address. This will be needed to implement the new
  adj-rib-out which hangs of pt_entry structs.

I will split up this diff before commit.
This is from a much bigger diff that I try to split up into more managable
chunks.
-- 
:wq Claudio


Index: rde.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde.c,v
diff -u -p -r1.675 rde.c
--- rde.c	12 Dec 2025 21:42:58 -0000	1.675
+++ rde.c	16 Dec 2025 10:25:36 -0000
@@ -3256,13 +3256,13 @@ rde_dump_ctx_new(struct ctl_show_rib_req
 						if (pte == NULL)
 							continue;
 						/* dump all matching paths */
-						p = adjout_prefix_first(peer,
-						    pte);
-						while (p != NULL) {
+						for (p = adjout_prefix_first(
+						    peer, pte);
+						    p != NULL;
+						    p = adjout_prefix_next(
+						    peer, pte, p)) {
 							rde_dump_adjout_upcall(
 							    peer, pte, p, ctx);
-							p = adjout_prefix_next(
-							    peer, p);
 						}
 					}
 					continue;
@@ -3276,10 +3276,11 @@ rde_dump_ctx_new(struct ctl_show_rib_req
 					continue;
 
 				/* dump all matching paths */
-				p = adjout_prefix_first(peer, pte);
-				while (p != NULL) {
-					rde_dump_adjout_upcall(peer, pte, p, ctx);
-					p = adjout_prefix_next(peer, p);
+				for (p = adjout_prefix_first(peer, pte);
+				    p != NULL;
+				    p = adjout_prefix_next(peer, pte, p)) {
+					rde_dump_adjout_upcall(peer, pte, p,
+					    ctx);
 				}
 			} while ((peer = peer_match(&req->neighbor,
 			    peer->conf.id)));
@@ -3545,7 +3546,7 @@ static void
 rde_up_flush_upcall(struct rde_peer *peer, struct pt_entry *pte,
     struct adjout_prefix *p, void *ptr)
 {
-	adjout_prefix_withdraw(peer, p);
+	adjout_prefix_withdraw(peer, pte, p);
 }
 
 int
Index: rde.h
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde.h,v
diff -u -p -r1.333 rde.h
--- rde.h	15 Dec 2025 12:16:19 -0000	1.333
+++ rde.h	16 Dec 2025 10:28:38 -0000
@@ -558,9 +558,12 @@ void	 pt_getaddr(struct pt_entry *, stru
 int	 pt_getflowspec(struct pt_entry *, uint8_t **);
 struct pt_entry	*pt_fill(struct bgpd_addr *, int);
 struct pt_entry	*pt_get(struct bgpd_addr *, int);
-struct pt_entry *pt_add(struct bgpd_addr *, int);
+struct pt_entry	*pt_get_next(struct bgpd_addr *, int);
+struct pt_entry	*pt_add(struct bgpd_addr *, int);
 struct pt_entry	*pt_get_flow(struct flowspec *);
 struct pt_entry	*pt_add_flow(struct flowspec *);
+struct pt_entry	*pt_first(uint8_t);
+struct pt_entry	*pt_next(struct pt_entry *);
 void	 pt_remove(struct pt_entry *);
 struct pt_entry	*pt_lookup(struct bgpd_addr *);
 int	 pt_prefix_cmp(const struct pt_entry *, const struct pt_entry *);
@@ -738,12 +741,12 @@ struct adjout_prefix	*adjout_prefix_get(
 struct adjout_prefix	*adjout_prefix_first(struct rde_peer *,
 			    struct pt_entry *);
 struct adjout_prefix	*adjout_prefix_next(struct rde_peer *,
-			    struct adjout_prefix *);
+			    struct pt_entry *, struct adjout_prefix *);
 
 void		 prefix_add_eor(struct rde_peer *, uint8_t);
 void		 adjout_prefix_update(struct adjout_prefix *, struct rde_peer *,
 		    struct filterstate *, struct pt_entry *, uint32_t);
-void		 adjout_prefix_withdraw(struct rde_peer *,
+void		 adjout_prefix_withdraw(struct rde_peer *, struct pt_entry *,
 		    struct adjout_prefix *);
 void		 adjout_prefix_destroy(struct rde_peer *,
 		    struct adjout_prefix *);
Index: rde_adjout.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde_adjout.c,v
diff -u -p -r1.13 rde_adjout.c
--- rde_adjout.c	15 Dec 2025 12:16:19 -0000	1.13
+++ rde_adjout.c	16 Dec 2025 10:30:28 -0000
@@ -480,7 +480,8 @@ adjout_prefix_first(struct rde_peer *pee
  * Return next prefix after a lookup that is actually an update.
  */
 struct adjout_prefix *
-adjout_prefix_next(struct rde_peer *peer, struct adjout_prefix *p)
+adjout_prefix_next(struct rde_peer *peer, struct pt_entry *pte,
+    struct adjout_prefix *p)
 {
 	struct adjout_prefix *np;
 
@@ -553,10 +554,11 @@ adjout_prefix_update(struct adjout_prefi
  * the prefix in the RIB linked to the peer withdraw list.
  */
 void
-adjout_prefix_withdraw(struct rde_peer *peer, struct adjout_prefix *p)
+adjout_prefix_withdraw(struct rde_peer *peer, struct pt_entry *pte,
+    struct adjout_prefix *p)
 {
 	if (peer_is_up(peer))
-		pend_prefix_add(peer, NULL, p->pt, p->path_id_tx);
+		pend_prefix_add(peer, NULL, pte, p->path_id_tx);
 
 	adjout_prefix_destroy(peer, p);
 }
Index: rde_community.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde_community.c,v
diff -u -p -r1.19 rde_community.c
--- rde_community.c	13 Nov 2025 15:52:47 -0000	1.19
+++ rde_community.c	16 Dec 2025 10:25:36 -0000
@@ -228,9 +228,9 @@ insert_community(struct rde_community *c
 		int newsize = comm->size + 8;
 
 		if ((new = reallocarray(comm->communities, newsize,
-		    sizeof(struct community))) == NULL)
+		    sizeof(*new))) == NULL)
 			fatal(__func__);
-		memset(&new[comm->size], 0, sizeof(struct community) * 8);
+		memset(&new[comm->size], 0, sizeof(*new) * 8);
 		comm->communities = new;
 		comm->size = newsize;
 	}
Index: rde_prefix.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde_prefix.c,v
diff -u -p -r1.58 rde_prefix.c
--- rde_prefix.c	27 Feb 2025 14:03:32 -0000	1.58
+++ rde_prefix.c	16 Dec 2025 10:25:36 -0000
@@ -329,6 +329,15 @@ pt_get(struct bgpd_addr *prefix, int pre
 }
 
 struct pt_entry *
+pt_get_next(struct bgpd_addr *prefix, int prefixlen)
+{
+	struct pt_entry	*pte;
+
+	pte = pt_fill(prefix, prefixlen);
+	return RB_NFIND(pt_tree, &pttable, pte);
+}
+
+struct pt_entry *
 pt_add(struct bgpd_addr *prefix, int prefixlen)
 {
 	struct pt_entry		*p = NULL;
@@ -382,6 +391,25 @@ pt_add_flow(struct flowspec *f)
 		fatalx("pt_add: insert failed");
 
 	return (p);
+}
+
+struct pt_entry *
+pt_first(uint8_t aid)
+{
+	struct pt_entry	*pte;
+	struct bgpd_addr addr = { .aid = aid };
+
+	if (aid == AID_UNSPEC)
+		return RB_MIN(pt_tree, &pttable);
+
+	pte = pt_fill(&addr, 0);
+	return RB_NFIND(pt_tree, &pttable, pte);
+}
+
+struct pt_entry *
+pt_next(struct pt_entry *pte)
+{
+	return RB_NEXT(pt_tree, &pttable, pte);
 }
 
 void
Index: rde_update.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde_update.c,v
diff -u -p -r1.190 rde_update.c
--- rde_update.c	15 Dec 2025 12:16:19 -0000	1.190
+++ rde_update.c	16 Dec 2025 10:25:36 -0000
@@ -244,7 +244,7 @@ up_generate_updates(struct rde_peer *pee
 done:
 	/* withdraw prefix */
 	if (p != NULL)
-		adjout_prefix_withdraw(peer, p);
+		adjout_prefix_withdraw(peer, re->prefix, p);
 }
 
 /*
@@ -266,7 +266,7 @@ up_generate_addpath(struct rde_peer *pee
 
 	/* collect all current paths */
 	head = adjout_prefix_first(peer, re->prefix);
-	for (p = head; p != NULL; p = adjout_prefix_next(peer, p)) {
+	for (p = head; p != NULL; p = adjout_prefix_next(peer, re->prefix, p)) {
 		addpath_prefix_list[pidx++] = p->path_id_tx;
 		if (pidx >= nitems(addpath_prefix_list))
 			fatalx("too many addpath paths to select from");
@@ -347,7 +347,7 @@ up_generate_addpath(struct rde_peer *pee
 			p = adjout_prefix_get(peer, addpath_prefix_list[i],
 			    re->prefix);
 			if (p != NULL)
-				adjout_prefix_withdraw(peer, p);
+				adjout_prefix_withdraw(peer, re->prefix, p);
 		}
 	}
 }
@@ -397,7 +397,7 @@ up_generate_addpath_all(struct rde_peer 
 		/* withdraw old path */
 		p = adjout_prefix_get(peer, old_pathid_tx, re->prefix);
 		if (p != NULL)
-			adjout_prefix_withdraw(peer, p);
+			adjout_prefix_withdraw(peer, re->prefix, p);
 	}
 }