VPLS signaling support.

This patch introduces full support for pseudowire signaling in ldpd(8),
including Control Word and Status TLV negotiation.

As of now it's not possible to configure a VPWS, but the signaling is
the same. In the future, when VPWS support is available in the kernel,
ldpd(8) can be extended to support VPWS with only a few modifications.

Limitations:
* No support for FEC 129, only FEC 128 (more widely deployed);
* No support for group withdraws (not widely deployed);
* No support for MAC withdraws (not widely deployed).

Related RFCs:
* RFC 3916: Requirements for Pseudo-Wire Emulation Edge-to-Edge (PWE3)
* RFC 3985: Pseudo Wire Emulation Edge-to-Edge (PWE3) Architecture
* RFC 4385: Pseudowire Emulation Edge-to-Edge (PWE3) Control Word for
  Use over an MPLS PSN
* RFC 4446: IANA Allocations for Pseudowire Edge to Edge Emulation (PWE3)
* RFC 4447: Pseudowire Setup and Maintenance Using the Label Distribution
  Protocol (LDP)
* RFC 4448: Encapsulation Methods for Transport of Ethernet over MPLS
  Networks
* RFC 4905: Encapsulation Methods for Transport of Layer 2 Frames over
  MPLS Networks
* RFC 4906: Transport of Layer 2 Frames Over MPLS

ok claudio@

1 files changed, 124 insertions, 87 deletions

diff --git a/usr.sbin/ldpd/lde_lib.c b/usr.sbin/ldpd/lde_lib.c
index b21c1d92477..d95da676cf7 100644
--- a/usr.sbin/ldpd/lde_lib.c
+++ b/usr.sbin/ldpd/lde_lib.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lde_lib.c,v 1.39 2015/07/21 04:48:42 renato Exp $ */
+/*	$OpenBSD: lde_lib.c,v 1.40 2015/07/21 04:52:29 renato Exp $ */
 
 /*
  * Copyright (c) 2009 Michele Marchetto <michele@openbsd.org>
@@ -41,8 +41,7 @@
 static int fec_compare(struct fec *, struct fec *);
 
 void		 fec_free(void *);
-struct fec_node	*fec_add(struct in_addr, u_int8_t);
-struct fec_nh	*fec_nh_find(struct fec_node *, struct in_addr);
+struct fec_node	*fec_add(struct fec *fec);
 struct fec_nh	*fec_nh_add(struct fec_node *, struct in_addr);
 void		 fec_nh_del(struct fec_nh *);
 int		 lde_nbr_is_nexthop(struct fec_node *, struct lde_nbr *);
@@ -66,27 +65,45 @@ fec_init(struct fec_tree *fh)
 static int
 fec_compare(struct fec *a, struct fec *b)
 {
-	if (ntohl(a->prefix.s_addr) < ntohl(b->prefix.s_addr))
+	if (a->type < b->type)
 		return (-1);
-	if (ntohl(a->prefix.s_addr) > ntohl(b->prefix.s_addr))
+	if (a->type > b->type)
 		return (1);
-	if (a->prefixlen < b->prefixlen)
-		return (-1);
-	if (a->prefixlen > b->prefixlen)
-		return (1);
-
-	return (0);
-}
 
-struct fec *
-fec_find_prefix(struct fec_tree *fh, in_addr_t prefix, u_int8_t prefixlen)
-{
-	struct fec	 s;
-
-	s.prefix.s_addr = prefix;
-	s.prefixlen = prefixlen;
+	switch (a->type) {
+	case FEC_TYPE_IPV4:
+		if (ntohl(a->u.ipv4.prefix.s_addr) <
+		    ntohl(b->u.ipv4.prefix.s_addr))
+			return (-1);
+		if (ntohl(a->u.ipv4.prefix.s_addr) >
+		    ntohl(b->u.ipv4.prefix.s_addr))
+			return (1);
+		if (a->u.ipv4.prefixlen < b->u.ipv4.prefixlen)
+			return (-1);
+		if (a->u.ipv4.prefixlen > b->u.ipv4.prefixlen)
+			return (1);
+		return (0);
+		break;
+	case FEC_TYPE_PWID:
+		if (a->u.pwid.type < b->u.pwid.type)
+			return (-1);
+		if (a->u.pwid.type > b->u.pwid.type)
+			return (1);
+		if (a->u.pwid.pwid < b->u.pwid.pwid)
+			return (-1);
+		if (a->u.pwid.pwid > b->u.pwid.pwid)
+			return (1);
+		if (ntohl(a->u.pwid.nexthop.s_addr) <
+		    ntohl(b->u.pwid.nexthop.s_addr))
+			return (-1);
+		if (ntohl(a->u.pwid.nexthop.s_addr) >
+		    ntohl(b->u.pwid.nexthop.s_addr))
+			return (1);
+		return (0);
+		break;
+	}
 
-	return (fec_find(fh, &s));
+	return (-1);
 }
 
 struct fec *
@@ -107,8 +124,7 @@ int
 fec_remove(struct fec_tree *fh, struct fec *f)
 {
 	if (RB_REMOVE(fec_tree, fh, f) == NULL) {
-		log_warnx("fec_remove failed for %s/%u",
-		    inet_ntoa(f->prefix), f->prefixlen);
+		log_warnx("fec_remove failed for %s", log_fec(f));
 		return (-1);
 	}
 	return (0);
@@ -148,13 +164,15 @@ rt_dump(pid_t pid)
 
 	RB_FOREACH(f, fec_tree, &ft) {
 		fn = (struct fec_node *)f;
+		if (fn->fec.type != FEC_TYPE_IPV4)
+			continue;
+
 		if (fn->local_label == NO_LABEL &&
 		    LIST_EMPTY(&fn->downstream))
 			continue;
 
-		rtctl.prefix = fn->fec.prefix;
-		rtctl.prefixlen = fn->fec.prefixlen;
-		rtctl.flags = fn->flags;
+		rtctl.prefix = fn->fec.u.ipv4.prefix;
+		rtctl.prefixlen = fn->fec.u.ipv4.prefixlen;
 		rtctl.local_label = fn->local_label;
 
 		LIST_FOREACH(me, &fn->downstream, entry) {
@@ -188,7 +206,7 @@ fec_snap(struct lde_nbr *ln)
 		if (fn->local_label == NO_LABEL)
 			continue;
 
-		lde_send_labelmapping(ln, fn);
+		lde_send_labelmapping(ln, fn, 0);
 		count++;
 	}
 	if (count > 0)
@@ -205,11 +223,11 @@ fec_free(void *arg)
 	while ((fnh = LIST_FIRST(&fn->nexthops)))
 		fec_nh_del(fnh);
 	if (!LIST_EMPTY(&fn->downstream))
-		log_warnx("fec_free: fec %s/%u downstream list not empty",
-		    inet_ntoa(fn->fec.prefix), fn->fec.prefixlen);
+		log_warnx("fec_free: fec %s downstream list not empty",
+		    log_fec(&fn->fec));
 	if (!LIST_EMPTY(&fn->upstream))
-		log_warnx("fec_free: fec %s/%u upstream list not empty",
-		    inet_ntoa(fn->fec.prefix), fn->fec.prefixlen);
+		log_warnx("fec_free: fec %s upstream list not empty",
+		    log_fec(&fn->fec));
 
 	free(fn);
 }
@@ -221,7 +239,7 @@ fec_tree_clear(void)
 }
 
 struct fec_node *
-fec_add(struct in_addr prefix, u_int8_t prefixlen)
+fec_add(struct fec *fec)
 {
 	struct fec_node	*fn;
 
@@ -229,16 +247,15 @@ fec_add(struct in_addr prefix, u_int8_t prefixlen)
 	if (fn == NULL)
 		fatal("fec_add");
 
-	fn->fec.prefix.s_addr = prefix.s_addr;
-	fn->fec.prefixlen = prefixlen;
+	memcpy(&fn->fec, fec, sizeof(fn->fec));
 	fn->local_label = NO_LABEL;
 	LIST_INIT(&fn->upstream);
 	LIST_INIT(&fn->downstream);
 	LIST_INIT(&fn->nexthops);
 
 	if (fec_insert(&ft, &fn->fec))
-		log_warnx("failed to add %s/%u to ft tree",
-		    inet_ntoa(fn->fec.prefix), fn->fec.prefixlen);
+		log_warnx("failed to add %s to ft tree",
+		    log_fec(&fn->fec));
 
 	return (fn);
 }
@@ -278,35 +295,33 @@ fec_nh_del(struct fec_nh *fnh)
 }
 
 void
-lde_kernel_insert(struct kroute *kr)
+lde_kernel_insert(struct fec *fec, struct in_addr nexthop, int connected,
+    void *data)
 {
 	struct fec_node		*fn;
 	struct fec_nh		*fnh;
 	struct lde_map		*me;
 	struct lde_nbr		*ln;
-	char			 buf[16];
 
-	log_debug("kernel add route %s/%u nexthop %s",
-	    inet_ntoa(kr->prefix), kr->prefixlen,
-	    inet_ntop(AF_INET, &kr->nexthop, buf, sizeof(buf)));
+	log_debug("lde add fec %s nexthop %s",
+	    log_fec(fec), inet_ntoa(nexthop));
 
-	fn = (struct fec_node *)fec_find_prefix(&ft, kr->prefix.s_addr,
-	    kr->prefixlen);
+	fn = (struct fec_node *)fec_find(&ft, fec);
 	if (fn == NULL)
-		fn = fec_add(kr->prefix, kr->prefixlen);
+		fn = fec_add(fec);
 
-	if (fec_nh_find(fn, kr->nexthop) != NULL)
+	if (fec_nh_find(fn, nexthop) != NULL)
 		return;
 
 	if (LIST_EMPTY(&fn->nexthops)) {
 		if (fn->local_label == NO_LABEL) {
-			if (kr->flags & F_CONNECTED)
+			if (connected)
 				fn->local_label = MPLS_LABEL_IMPLNULL;
 			else
 				fn->local_label = lde_assign_label();
 		} else {
 			/* Handle local label changes */
-			if ((kr->flags & F_CONNECTED) &&
+			if (connected &&
 			    fn->local_label != MPLS_LABEL_IMPLNULL) {
 				/* explicit withdraw of the previous label */
 				RB_FOREACH(ln, nbr_tree, &lde_nbrs)
@@ -314,7 +329,7 @@ lde_kernel_insert(struct kroute *kr)
 				fn->local_label = MPLS_LABEL_IMPLNULL;
 			}
 
-			if (!(kr->flags & F_CONNECTED) &&
+			if (!connected &&
 			    fn->local_label == MPLS_LABEL_IMPLNULL) {
 				/* explicit withdraw of the previous label */
 				RB_FOREACH(ln, nbr_tree, &lde_nbrs)
@@ -324,16 +339,13 @@ lde_kernel_insert(struct kroute *kr)
 		}
 
 		/* FEC.1: perform lsr label distribution procedure */
-		RB_FOREACH(ln, nbr_tree, &lde_nbrs) {
-			lde_send_labelmapping(ln, fn);
-			lde_imsg_compose_ldpe(IMSG_MAPPING_ADD_END,
-			    ln->peerid, 0, NULL, 0);
-		}
+		RB_FOREACH(ln, nbr_tree, &lde_nbrs)
+			lde_send_labelmapping(ln, fn, 1);
 	}
 
-	fnh = fec_nh_add(fn, kr->nexthop);
+	fnh = fec_nh_add(fn, nexthop);
+	fnh->data = data;
 	lde_send_change_klabel(fn, fnh);
-
 	ln = lde_find_address(fnh->nexthop);
 	if (ln) {
 		/* FEC.2  */
@@ -345,28 +357,26 @@ lde_kernel_insert(struct kroute *kr)
 }
 
 void
-lde_kernel_remove(struct kroute *kr)
+lde_kernel_remove(struct fec *fec, struct in_addr nexthop)
 {
 	struct fec_node		*fn;
 	struct fec_nh		*fnh;
 	struct lde_nbr		*ln;
-	char			 buf[16];
 
-	log_debug("kernel remove route %s/%u nexthop %s",
-	    inet_ntoa(kr->prefix), kr->prefixlen,
-	    inet_ntop(AF_INET, &kr->nexthop, buf, sizeof(buf)));
+	log_debug("lde remove fec %s nexthop %s",
+	    log_fec(fec), inet_ntoa(nexthop));
 
-	fn = (struct fec_node *)fec_find_prefix(&ft, kr->prefix.s_addr,
-	    kr->prefixlen);
+	fn = (struct fec_node *)fec_find(&ft, fec);
 	if (fn == NULL)
 		/* route lost */
 		return;
 
-	fnh = fec_nh_find(fn, kr->nexthop);
+	fnh = fec_nh_find(fn, nexthop);
 	if (fnh == NULL)
 		/* route lost */
 		return;
 
+	lde_send_delete_klabel(fn, fnh);
 	fec_nh_del(fnh);
 	if (LIST_EMPTY(&fn->nexthops))
 		RB_FOREACH(ln, nbr_tree, &lde_nbrs)
@@ -376,17 +386,19 @@ lde_kernel_remove(struct kroute *kr)
 void
 lde_check_mapping(struct map *map, struct lde_nbr *ln)
 {
+	struct fec		 fec;
 	struct fec_node		*fn;
 	struct fec_nh		*fnh;
 	struct lde_req		*lre;
 	struct lde_nbr_address	*addr;
 	struct lde_map		*me;
+	struct l2vpn_pw		*pw;
 	int			 msgsource = 0;
 
-	fn = (struct fec_node *)fec_find_prefix(&ft, map->prefix.s_addr,
-	    map->prefixlen);
+	lde_map2fec(map, ln->id, &fec);
+	fn = (struct fec_node *)fec_find(&ft, &fec);
 	if (fn == NULL)
-		fn = fec_add(map->prefix, map->prefixlen);
+		fn = fec_add(&fec);
 
 	/* LMp.1: first check if we have a pending request running */
 	lre = (struct lde_req *)fec_find(&ln->sent_req, &fn->fec);
@@ -394,6 +406,10 @@ lde_check_mapping(struct map *map, struct lde_nbr *ln)
 		/* LMp.2: delete record of outstanding label request */
 		lde_req_del(ln, lre, 1);
 
+	/* RFC 4447 control word and status tlv negotiation */
+	if (map->type == FEC_PWID && l2vpn_pw_negotiate(ln, fn, map))
+		return;
+
 	/*
 	 * LMp.3 - LMp.8: Loop detection LMp.3 - unecessary for frame-mode
 	 * mpls networks
@@ -422,27 +438,38 @@ lde_check_mapping(struct map *map, struct lde_nbr *ln)
 	 * support multipath
 	 */
 	LIST_FOREACH(fnh, &fn->nexthops, entry) {
-		if (lde_address_find(ln, &fnh->nexthop)) {
-			msgsource = 1;
+		if (lde_address_find(ln, &fnh->nexthop) == NULL)
+			continue;
 
-			/* LMp.15: install FEC in FIB */
-			fnh->remote_label = map->label;
+		msgsource = 1;
+
+		/* LMp.15: install FEC in FIB */
+		fnh->remote_label = map->label;
+		switch (map->type) {
+		case FEC_PREFIX:
 			lde_send_change_klabel(fn, fnh);
+			break;
+		case FEC_PWID:
+			pw = (struct l2vpn_pw *) fnh->data;
+			pw->remote_group = map->fec.pwid.group_id;
+			if (map->flags & F_MAP_PW_IFMTU)
+				pw->remote_mtu = map->fec.pwid.ifmtu;
+			if (map->flags & F_MAP_PW_STATUS)
+				pw->remote_status = map->pw_status;
+			if (l2vpn_pw_ok(pw, fnh))
+				lde_send_change_klabel(fn, fnh);
+			break;
 		}
 	}
-	if (msgsource == 0) {
-		/* LMp.13: perform lsr label release procedure */
-		if (me == NULL)
-			me = lde_map_add(ln, fn, 0);
-		memcpy(&me->map, map, sizeof(*map));
-		return;
-	}
-
-	/* LMp.16: Record the mapping from this peer */
+	/* LMp.13 & LMp.16: Record the mapping from this peer */
 	if (me == NULL)
 		me = lde_map_add(ln, fn, 0);
 	memcpy(&me->map, map, sizeof(*map));
 
+	if (msgsource == 0)
+		/* LMp.13: just return since we use liberal lbl retention */
+		return;
+
 	/*
 	 * LMp.17 - LMp.27 are unnecessary since we don't need to implement
 	 * loop detection. LMp.28 - LMp.30 are unnecessary because we are
@@ -453,6 +480,7 @@ lde_check_mapping(struct map *map, struct lde_nbr *ln)
 void
 lde_check_request(struct map *map, struct lde_nbr *ln)
 {
+	struct fec	 fec;
 	struct lde_req	*lre;
 	struct fec_node	*fn;
 	struct fec_nh	*fnh;
@@ -460,8 +488,8 @@ lde_check_request(struct map *map, struct lde_nbr *ln)
 	/* TODO LRq.1: loop detection */
 
 	/* LRq.2: is there a next hop for fec? */
-	fn = (struct fec_node *)fec_find_prefix(&ft, map->prefix.s_addr,
-	    map->prefixlen);
+	lde_map2fec(map, ln->id, &fec);
+	fn = (struct fec_node *)fec_find(&ft, &fec);
 	if (fn == NULL || LIST_EMPTY(&fn->nexthops)) {
 		lde_send_notification(ln->peerid, S_NO_ROUTE, map->messageid,
 		    MSG_TYPE_LABELREQUEST);
@@ -489,8 +517,7 @@ lde_check_request(struct map *map, struct lde_nbr *ln)
 		lre->msgid = map->messageid;
 
 	/* LRq.9: perform LSR label distribution */
-	lde_send_labelmapping(ln, fn);
-	lde_imsg_compose_ldpe(IMSG_MAPPING_ADD_END, ln->peerid, 0, NULL, 0);
+	lde_send_labelmapping(ln, fn, 1);
 
 	/*
 	 * LRq.10: do nothing (Request Never) since we use liberal
@@ -502,12 +529,17 @@ lde_check_request(struct map *map, struct lde_nbr *ln)
 void
 lde_check_release(struct map *map, struct lde_nbr *ln)
 {
+	struct fec		 fec;
 	struct fec_node		*fn;
 	struct lde_wdraw	*lw;
 	struct lde_map		*me;
 
-	fn = (struct fec_node *)fec_find_prefix(&ft, map->prefix.s_addr,
-	    map->prefixlen);
+	/* TODO group wildcard */
+	if (!(map->flags & F_MAP_PW_ID))
+		return;
+
+	lde_map2fec(map, ln->id, &fec);
+	fn = (struct fec_node *)fec_find(&ft, &fec);
 	/* LRl.1: does FEC match a known FEC? */
 	if (fn == NULL)
 		return;
@@ -567,14 +599,19 @@ lde_check_release_wcard(struct map *map, struct lde_nbr *ln)
 void
 lde_check_withdraw(struct map *map, struct lde_nbr *ln)
 {
+	struct fec	 fec;
 	struct fec_node	*fn;
 	struct fec_nh	*fnh;
 	struct lde_map	*me;
 
-	fn = (struct fec_node *)fec_find_prefix(&ft, map->prefix.s_addr,
-	    map->prefixlen);
+	/* TODO group wildcard */
+	if (!(map->flags & F_MAP_PW_ID))
+		return;
+
+	lde_map2fec(map, ln->id, &fec);
+	fn = (struct fec_node *)fec_find(&ft, &fec);
 	if (fn == NULL)
-		fn = fec_add(map->prefix, map->prefixlen);
+		fn = fec_add(&fec);
 
 	/* LWd.1: remove label from forwarding/switching use */
 	LIST_FOREACH(fnh, &fn->nexthops, entry) {