ldpd: implement support for PWid group wildcards

This was missing from our original RFC 4447 VPLS implementation. Now
ldpd understands group wildcards as mandated by the RFC, but we still
don't send them ourselves. I can't see any case in which sending a group
wildcard would be useful, but nonetheless this patch provides a function
called lde_send_labelwithdraw_pwid_wcard() which is ready to be used in
the future anytime we feel like it might be useful.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

1 files changed, 46 insertions, 10 deletions

diff --git a/ldpd/lde_lib.c b/ldpd/lde_lib.c
index 02730189a..c37a9e966 100644
--- a/ldpd/lde_lib.c
+++ b/ldpd/lde_lib.c
@@ -374,7 +374,8 @@ lde_kernel_update(struct fec *fec)
 	}
 
 	if (LIST_EMPTY(&fn->nexthops)) {
-		lde_send_labelwithdraw_all(fn, NO_LABEL);
+		RB_FOREACH(ln, nbr_tree, &lde_nbrs)
+			lde_send_labelwithdraw(ln, fn, NULL, NULL);
 		fn->local_label = NO_LABEL;
 		fn->data = NULL;
 	} else {
@@ -478,7 +479,7 @@ lde_check_mapping(struct map *map, struct lde_nbr *ln)
 		/* LMp.10 */
 		if (me->map.label != map->label && lre == NULL) {
 			/* LMp.10a */
-			lde_send_labelrelease(ln, fn, me->map.label);
+			lde_send_labelrelease(ln, fn, NULL, me->map.label);
 
 			/*
 			 * Can not use lde_nbr_find_by_addr() because there's
@@ -612,9 +613,12 @@ lde_check_release(struct map *map, struct lde_nbr *ln)
 	struct lde_wdraw	*lw;
 	struct lde_map		*me;
 
-	/* TODO group wildcard */
-	if (map->type == MAP_TYPE_PWID && !(map->flags & F_MAP_PW_ID))
+	/* wildcard label release */
+	if (map->type == MAP_TYPE_WILDCARD ||
+	    (map->type == MAP_TYPE_PWID && !(map->flags & F_MAP_PW_ID))) {
+		lde_check_release_wcard(map, ln);
 		return;
+	}
 
 	lde_map2fec(map, ln->id, &fec);
 	fn = (struct fec_node *)fec_find(&ft, &fec);
@@ -650,6 +654,11 @@ lde_check_release_wcard(struct map *map, struct lde_nbr *ln)
 
 	RB_FOREACH(f, fec_tree, &ft) {
 		fn = (struct fec_node *)f;
+		me = (struct lde_map *)fec_find(&ln->sent_map, &fn->fec);
+
+		/* LRl.1: does FEC match a known FEC? */
+		if (lde_wildcard_apply(map, &fn->fec, me) == 0)
+			continue;
 
 		/* LRl.3: first check if we have a pending withdraw running */
 		lw = (struct lde_wdraw *)fec_find(&ln->sent_wdraw, &fn->fec);
@@ -659,7 +668,6 @@ lde_check_release_wcard(struct map *map, struct lde_nbr *ln)
 		}
 
 		/* LRl.6: check sent map list and remove it if available */
-		me = (struct lde_map *)fec_find(&ln->sent_map, &fn->fec);
 		if (me &&
 		    (map->label == NO_LABEL || map->label == me->map.label))
 			lde_map_del(ln, me, 1);
@@ -680,9 +688,12 @@ lde_check_withdraw(struct map *map, struct lde_nbr *ln)
 	struct lde_map		*me;
 	struct l2vpn_pw		*pw;
 
-	/* TODO group wildcard */
-	if (map->type == MAP_TYPE_PWID && !(map->flags & F_MAP_PW_ID))
+	/* wildcard label withdraw */
+	if (map->type == MAP_TYPE_WILDCARD ||
+	    (map->type == MAP_TYPE_PWID && !(map->flags & F_MAP_PW_ID))) {
+		lde_check_withdraw_wcard(map, ln);
 		return;
+	}
 
 	lde_map2fec(map, ln->id, &fec);
 	fn = (struct fec_node *)fec_find(&ft, &fec);
@@ -713,7 +724,7 @@ lde_check_withdraw(struct map *map, struct lde_nbr *ln)
 	}
 
 	/* LWd.2: send label release */
-	lde_send_labelrelease(ln, fn, map->label);
+	lde_send_labelrelease(ln, fn, NULL, map->label);
 
 	/* LWd.3: check previously received label mapping */
 	me = (struct lde_map *)fec_find(&ln->recv_map, &fn->fec);
@@ -731,10 +742,14 @@ lde_check_withdraw_wcard(struct map *map, struct lde_nbr *ln)
 	struct lde_map	*me;
 
 	/* LWd.2: send label release */
-	lde_send_labelrelease(ln, NULL, map->label);
+	lde_send_labelrelease(ln, NULL, map, map->label);
 
 	RB_FOREACH(f, fec_tree, &ft) {
 		fn = (struct fec_node *)f;
+		me = (struct lde_map *)fec_find(&ln->recv_map, &fn->fec);
+
+		if (lde_wildcard_apply(map, &fn->fec, me) == 0)
+			continue;
 
 		/* LWd.1: remove label from forwarding/switching use */
 		LIST_FOREACH(fnh, &fn->nexthops, entry) {
@@ -761,7 +776,6 @@ lde_check_withdraw_wcard(struct map *map, struct lde_nbr *ln)
 		}
 
 		/* LWd.3: check previously received label mapping */
-		me = (struct lde_map *)fec_find(&ln->recv_map, &fn->fec);
 		if (me && (map->label == NO_LABEL ||
 		    map->label == me->map.label))
 			/*
@@ -772,6 +786,28 @@ lde_check_withdraw_wcard(struct map *map, struct lde_nbr *ln)
 	}
 }
 
+int
+lde_wildcard_apply(struct map *wcard, struct fec *fec, struct lde_map *me)
+{
+	switch (wcard->type) {
+	case MAP_TYPE_WILDCARD:
+		/* full wildcard */
+		return (1);
+	case MAP_TYPE_PWID:
+		/* RFC4447 pw-id group wildcard */
+		if (fec->type != FEC_TYPE_PWID)
+			return (0);
+		if (fec->u.pwid.type != wcard->fec.pwid.type)
+			return (0);
+		if (me == NULL || (me->map.fec.pwid.group_id !=
+		    wcard->fec.pwid.group_id))
+			return (0);
+		return (1);
+	default:
+		fatalx("lde_wildcard_apply: unexpected fec type");
+	}
+}
+
 /* gabage collector timer: timer to remove dead entries from the LIB */
 
 /* ARGSUSED */