ldpd: implement RFC 5919 (LDP End-of-LIB)

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

9 files changed, 192 insertions, 43 deletions

diff --git a/ldpd/init.c b/ldpd/init.c
index 13104b4ee..bc3a69edc 100644
--- a/ldpd/init.c
+++ b/ldpd/init.c
@@ -26,6 +26,7 @@
 static int	gen_init_prms_tlv(struct ibuf *, struct nbr *);
 static int	gen_cap_dynamic_tlv(struct ibuf *);
 static int	gen_cap_twcard_tlv(struct ibuf *, int);
+static int	gen_cap_unotif_tlv(struct ibuf *, int);
 
 void
 send_init(struct nbr *nbr)
@@ -37,7 +38,7 @@ send_init(struct nbr *nbr)
 	debug_msg_send("initialization: lsr-id %s", inet_ntoa(nbr->id));
 
 	size = LDP_HDR_SIZE + LDP_MSG_SIZE + SESS_PRMS_SIZE +
-	    CAP_TLV_DYNAMIC_SIZE + CAP_TLV_TWCARD_SIZE;
+	    CAP_TLV_DYNAMIC_SIZE + CAP_TLV_TWCARD_SIZE + CAP_TLV_UNOTIF_SIZE;
 	if ((buf = ibuf_open(size)) == NULL)
 		fatal(__func__);
 
@@ -47,6 +48,7 @@ send_init(struct nbr *nbr)
 	err |= gen_init_prms_tlv(buf, nbr);
 	err |= gen_cap_dynamic_tlv(buf);
 	err |= gen_cap_twcard_tlv(buf, 1);
+	err |= gen_cap_unotif_tlv(buf, 1);
 	if (err) {
 		ibuf_free(buf);
 		return;
@@ -167,6 +169,26 @@ recv_init(struct nbr *nbr, char *buf, uint16_t len)
 			log_debug("%s: lsr-id %s announced the Typed Wildcard "
 			    "FEC capability", __func__, inet_ntoa(nbr->id));
 			break;
+		case TLV_TYPE_UNOTIF_CAP:
+			if (tlv_len != CAP_TLV_UNOTIF_LEN) {
+				session_shutdown(nbr, S_BAD_TLV_LEN, msg.id,
+				    msg.type);
+				return (-1);
+			}
+
+			if (caps_rcvd & F_CAP_TLV_RCVD_UNOTIF) {
+				session_shutdown(nbr, S_BAD_TLV_VAL, msg.id,
+				    msg.type);
+				return (-1);
+			}
+			caps_rcvd |= F_CAP_TLV_RCVD_UNOTIF;
+
+			nbr->flags |= F_NBR_CAP_UNOTIF;
+
+			log_debug("%s: lsr-id %s announced the Unrecognized "
+			    "Notification capability", __func__,
+			    inet_ntoa(nbr->id));
+			break;
 		default:
 			if (!(ntohs(tlv.type) & UNKNOWN_FLAG))
 				send_notification_rtlvs(nbr, S_UNSSUPORTDCAP,
@@ -217,6 +239,9 @@ send_capability(struct nbr *nbr, uint16_t capability, int enable)
 	case TLV_TYPE_TWCARD_CAP:
 		err |= gen_cap_twcard_tlv(buf, enable);
 		break;
+	case TLV_TYPE_UNOTIF_CAP:
+		err |= gen_cap_unotif_tlv(buf, enable);
+		break;
 	case TLV_TYPE_DYNAMIC_CAP:
 		/*
 		 * RFC 5561 - Section 9:
@@ -299,6 +324,32 @@ recv_capability(struct nbr *nbr, char *buf, uint16_t len)
 			    "capability", __func__, inet_ntoa(nbr->id),
 			    (enable) ? "announced" : "withdrew");
 			break;
+		case TLV_TYPE_UNOTIF_CAP:
+			if (tlv_len != CAP_TLV_UNOTIF_LEN) {
+				session_shutdown(nbr, S_BAD_TLV_LEN, msg.id,
+				    msg.type);
+				return (-1);
+			}
+
+			if (caps_rcvd & F_CAP_TLV_RCVD_UNOTIF) {
+				session_shutdown(nbr, S_BAD_TLV_VAL, msg.id,
+				    msg.type);
+				return (-1);
+			}
+			caps_rcvd |= F_CAP_TLV_RCVD_UNOTIF;
+
+			memcpy(&reserved, buf, sizeof(reserved));
+			enable = reserved & STATE_BIT;
+			if (enable)
+				nbr->flags |= F_NBR_CAP_UNOTIF;
+			else
+				nbr->flags &= ~F_NBR_CAP_UNOTIF;
+
+			log_debug("%s: lsr-id %s %s the Unrecognized "
+			    "Notification capability", __func__,
+			    inet_ntoa(nbr->id), (enable) ? "announced" :
+			    "withdrew");
+			break;
 		case TLV_TYPE_DYNAMIC_CAP:
 			/*
 		 	 * RFC 5561 - Section 9:
@@ -371,3 +422,17 @@ gen_cap_twcard_tlv(struct ibuf *buf, int enable)
 
 	return (ibuf_add(buf, &cap, CAP_TLV_TWCARD_SIZE));
 }
+
+static int
+gen_cap_unotif_tlv(struct ibuf *buf, int enable)
+{
+	struct capability_tlv	cap;
+
+	memset(&cap, 0, sizeof(cap));
+	cap.type = htons(TLV_TYPE_UNOTIF_CAP);
+	cap.length = htons(CAP_TLV_UNOTIF_LEN);
+	if (enable)
+		cap.reserved = STATE_BIT;
+
+	return (ibuf_add(buf, &cap, CAP_TLV_UNOTIF_SIZE));
+}
diff --git a/ldpd/labelmapping.c b/ldpd/labelmapping.c
index 55b890ac7..75acfd7d5 100644
--- a/ldpd/labelmapping.c
+++ b/ldpd/labelmapping.c
@@ -72,36 +72,8 @@ send_labelmessage(struct nbr *nbr, uint16_t type, struct mapping_head *mh)
 		}
 
 		/* calculate size */
-		msg_size = LDP_MSG_SIZE + TLV_HDR_SIZE;
-		switch (me->map.type) {
-		case MAP_TYPE_WILDCARD:
-			msg_size += FEC_ELM_WCARD_LEN;
-			break;
-		case MAP_TYPE_PREFIX:
-			msg_size += FEC_ELM_PREFIX_MIN_LEN +
-			    PREFIX_SIZE(me->map.fec.prefix.prefixlen);
-			break;
-		case MAP_TYPE_PWID:
-			msg_size += FEC_PWID_ELM_MIN_LEN;
-			if (me->map.flags & F_MAP_PW_ID)
-				msg_size += PW_STATUS_TLV_LEN;
-			if (me->map.flags & F_MAP_PW_IFMTU)
-				msg_size += FEC_SUBTLV_IFMTU_SIZE;
-	    		if (me->map.flags & F_MAP_PW_STATUS)
-				msg_size += PW_STATUS_TLV_SIZE;
-			break;
-		case MAP_TYPE_TYPED_WCARD:
-			msg_size += FEC_ELM_TWCARD_MIN_LEN;
-			switch (me->map.fec.twcard.type) {
-			case MAP_TYPE_PREFIX:
-			case MAP_TYPE_PWID:
-				msg_size += sizeof(uint16_t);
-				break;
-			default:
-				fatalx("send_labelmessage: unexpected fec type");
-			}
-			break;
-		}
+		msg_size = LDP_MSG_SIZE;
+		msg_size += len_fec_tlv(&me->map);
 		if (me->map.label != NO_LABEL)
 			msg_size += LABEL_TLV_SIZE;
 		if (me->map.flags & F_MAP_REQ_ID)
@@ -548,6 +520,46 @@ gen_pw_status_tlv(struct ibuf *buf, uint32_t status)
 	return (ibuf_add(buf, &st, sizeof(st)));
 }
 
+uint16_t
+len_fec_tlv(struct map *map)
+{
+	uint16_t	 len = TLV_HDR_SIZE;
+
+	switch (map->type) {
+	case MAP_TYPE_WILDCARD:
+		len += FEC_ELM_WCARD_LEN;
+		break;
+	case MAP_TYPE_PREFIX:
+		len += FEC_ELM_PREFIX_MIN_LEN +
+		    PREFIX_SIZE(map->fec.prefix.prefixlen);
+		break;
+	case MAP_TYPE_PWID:
+		len += FEC_PWID_ELM_MIN_LEN;
+		if (map->flags & F_MAP_PW_ID)
+			len += PW_STATUS_TLV_LEN;
+		if (map->flags & F_MAP_PW_IFMTU)
+			len += FEC_SUBTLV_IFMTU_SIZE;
+    		if (map->flags & F_MAP_PW_STATUS)
+			len += PW_STATUS_TLV_SIZE;
+		break;
+	case MAP_TYPE_TYPED_WCARD:
+		len += FEC_ELM_TWCARD_MIN_LEN;
+		switch (map->fec.twcard.type) {
+		case MAP_TYPE_PREFIX:
+		case MAP_TYPE_PWID:
+			len += sizeof(uint16_t);
+			break;
+		default:
+			fatalx("len_fec_tlv: unexpected fec type");
+		}
+		break;
+	default:
+		fatalx("len_fec_tlv: unexpected fec type");
+	}
+
+	return (len);
+}
+
 int
 gen_fec_tlv(struct ibuf *buf, struct map *map)
 {
diff --git a/ldpd/lde.c b/ldpd/lde.c
index 2392dbf6d..e64f18dfc 100644
--- a/ldpd/lde.c
+++ b/ldpd/lde.c
@@ -319,6 +319,13 @@ lde_dispatch_imsg(struct thread *thread)
 			case S_PW_STATUS:
 				l2vpn_recv_pw_status(ln, &nm);
 				break;
+			case S_ENDOFLIB:
+				/*
+				 * Do nothing for now. Should be useful in
+				 * the future when we implement LDP-IGP
+				 * Synchronization (RFC 5443) and Graceful
+				 * Restart (RFC 3478).
+				 */
 			default:
 				break;
 			}
@@ -1099,6 +1106,38 @@ lde_send_notification(struct lde_nbr *ln, uint32_t status_code, uint32_t msg_id,
 	    &nm, sizeof(nm));
 }
 
+void
+lde_send_notification_eol_prefix(struct lde_nbr *ln, int af)
+{
+	struct notify_msg nm;
+
+	memset(&nm, 0, sizeof(nm));
+	nm.status_code = S_ENDOFLIB;
+	nm.fec.type = MAP_TYPE_TYPED_WCARD;
+	nm.fec.fec.twcard.type = MAP_TYPE_PREFIX;
+	nm.fec.fec.twcard.u.prefix_af = af;
+	nm.flags |= F_NOTIF_FEC;
+
+	lde_imsg_compose_ldpe(IMSG_NOTIFICATION_SEND, ln->peerid, 0,
+	    &nm, sizeof(nm));
+}
+
+void
+lde_send_notification_eol_pwid(struct lde_nbr *ln, uint16_t pw_type)
+{
+	struct notify_msg nm;
+
+	memset(&nm, 0, sizeof(nm));
+	nm.status_code = S_ENDOFLIB;
+	nm.fec.type = MAP_TYPE_TYPED_WCARD;
+	nm.fec.fec.twcard.type = MAP_TYPE_PWID;
+	nm.fec.fec.twcard.u.pw_type = pw_type;
+	nm.flags |= F_NOTIF_FEC;
+
+	lde_imsg_compose_ldpe(IMSG_NOTIFICATION_SEND, ln->peerid, 0,
+	    &nm, sizeof(nm));
+}
+
 static __inline int
 lde_nbr_compare(struct lde_nbr *a, struct lde_nbr *b)
 {
@@ -1116,6 +1155,7 @@ lde_nbr_new(uint32_t peerid, struct lde_nbr *new)
 	ln->id = new->id;
 	ln->v4_enabled = new->v4_enabled;
 	ln->v6_enabled = new->v6_enabled;
+	ln->flags = new->flags;
 	ln->peerid = peerid;
 	fec_init(&ln->recv_map);
 	fec_init(&ln->sent_map);
diff --git a/ldpd/lde.h b/ldpd/lde.h
index b3af1bbaa..a2b51dad3 100644
--- a/ldpd/lde.h
+++ b/ldpd/lde.h
@@ -90,6 +90,7 @@ struct lde_nbr {
 	struct in_addr		 id;
 	int			 v4_enabled;	/* announce/process v4 msgs */
 	int			 v6_enabled;	/* announce/process v6 msgs */
+	int			 flags;		/* capabilities */
 	struct fec_tree		 recv_req;
 	struct fec_tree		 sent_req;
 	struct fec_tree		 recv_map;
@@ -155,6 +156,8 @@ void		 lde_send_labelrelease(struct lde_nbr *, struct fec_node *,
 		    struct map *, uint32_t);
 void		 lde_send_notification(struct lde_nbr *, uint32_t, uint32_t,
 		    uint16_t);
+void		 lde_send_notification_eol_prefix(struct lde_nbr *, int);
+void		 lde_send_notification_eol_pwid(struct lde_nbr *, uint16_t);
 struct lde_nbr	*lde_nbr_find_by_lsrid(struct in_addr);
 struct lde_nbr	*lde_nbr_find_by_addr(int, union ldpd_addr *);
 struct lde_map	*lde_map_add(struct lde_nbr *, struct fec_node *, int);
diff --git a/ldpd/ldp.h b/ldpd/ldp.h
index ffdadf8be..0a42ab407 100644
--- a/ldpd/ldp.h
+++ b/ldpd/ldp.h
@@ -101,6 +101,8 @@
 #define TLV_TYPE_DYNAMIC_CAP	0x8506
 /* RFC 5918 */
 #define TLV_TYPE_TWCARD_CAP	0x850B
+/* RFC 5919 */
+#define TLV_TYPE_UNOTIF_CAP	0x8603
 /* RFC 7552 */
 #define TLV_TYPE_DUALSTACK	0x8701
 
@@ -204,6 +206,8 @@ struct hello_prms_opt16_tlv {
 #define S_WITHDRAW_MTHD	0x0000002B
 /* RFC 5561 */
 #define	S_UNSSUPORTDCAP	0x0000002E
+/* RFC 5919 */
+#define	S_ENDOFLIB	0x0000002F
 /* RFC 7552 */
 #define	S_TRANS_MISMTCH	0x80000032
 #define	S_DS_NONCMPLNCE	0x80000033
@@ -244,6 +248,7 @@ struct capability_tlv {
 
 #define F_CAP_TLV_RCVD_DYNAMIC	0x01
 #define F_CAP_TLV_RCVD_TWCARD	0x02
+#define F_CAP_TLV_RCVD_UNOTIF	0x04
 
 #define CAP_TLV_DYNAMIC_SIZE	5
 #define CAP_TLV_DYNAMIC_LEN	1
@@ -251,6 +256,9 @@ struct capability_tlv {
 #define CAP_TLV_TWCARD_SIZE	5
 #define CAP_TLV_TWCARD_LEN	1
 
+#define CAP_TLV_UNOTIF_SIZE	5
+#define CAP_TLV_UNOTIF_LEN	1
+
 #define	AF_IPV4			0x1
 #define	AF_IPV6			0x2
 
diff --git a/ldpd/ldpe.h b/ldpd/ldpe.h
index 24512989d..2bd0568d6 100644
--- a/ldpd/ldpe.h
+++ b/ldpd/ldpe.h
@@ -113,6 +113,7 @@ struct nbr {
 #define F_NBR_GTSM_NEGOTIATED	 0x01
 #define F_NBR_CAP_DYNAMIC	 0x02
 #define F_NBR_CAP_TWCARD	 0x04
+#define F_NBR_CAP_UNOTIF	 0x08
 
 RB_HEAD(nbr_id_head, nbr);
 RB_PROTOTYPE(nbr_id_head, nbr, id_tree, nbr_id_compare)
@@ -186,6 +187,7 @@ int	 recv_address(struct nbr *, char *, uint16_t);
 void	 send_labelmessage(struct nbr *, uint16_t, struct mapping_head *);
 int	 recv_labelmessage(struct nbr *, char *, uint16_t, uint16_t);
 int	 gen_pw_status_tlv(struct ibuf *, uint32_t);
+uint16_t len_fec_tlv(struct map *);
 int	 gen_fec_tlv(struct ibuf *, struct map *);
 int	 tlv_decode_fec_elm(struct nbr *, struct ldp_msg *, char *,
 	    uint16_t, struct map *);
diff --git a/ldpd/log.c b/ldpd/log.c
index 5ad8ca0ca..b30604db0 100644
--- a/ldpd/log.c
+++ b/ldpd/log.c
@@ -584,6 +584,8 @@ status_code_name(uint32_t status)
 		return ("Label Withdraw PW Status Method");
 	case S_UNSSUPORTDCAP:
 		return ("Unsupported Capability");
+	case S_ENDOFLIB:
+		return ("End-of-LIB");
 	case S_TRANS_MISMTCH:
 		return ("Transport Connection Mismatch");
 	case S_DS_NONCMPLNCE:
diff --git a/ldpd/neighbor.c b/ldpd/neighbor.c
index d24ceb122..077d47285 100644
--- a/ldpd/neighbor.c
+++ b/ldpd/neighbor.c
@@ -744,6 +744,7 @@ nbr_act_session_operational(struct nbr *nbr)
 	lde_nbr.id = nbr->id;
 	lde_nbr.v4_enabled = nbr->v4_enabled;
 	lde_nbr.v6_enabled = nbr->v6_enabled;
+	lde_nbr.flags = nbr->flags;
 	return (ldpe_imsg_compose_lde(IMSG_NEIGHBOR_UP, nbr->peerid, 0,
 	    &lde_nbr, sizeof(lde_nbr)));
 }
diff --git a/ldpd/notification.c b/ldpd/notification.c
index 69d4ab802..393994ed5 100644
--- a/ldpd/notification.c
+++ b/ldpd/notification.c
@@ -38,16 +38,8 @@ send_notification_full(struct tcp_conn *tcp, struct notify_msg *nm)
 	size = LDP_HDR_SIZE + LDP_MSG_SIZE + STATUS_SIZE;
 	if (nm->flags & F_NOTIF_PW_STATUS)
 		size += PW_STATUS_TLV_SIZE;
-	if (nm->flags & F_NOTIF_FEC) {
-		size += TLV_HDR_SIZE;
-		switch (nm->fec.type) {
-		case MAP_TYPE_PWID:
-			size += FEC_PWID_ELM_MIN_LEN;
-			if (nm->fec.flags & F_MAP_PW_ID)
-				size += sizeof(uint32_t);
-			break;
-		}
-	}
+	if (nm->flags & F_NOTIF_FEC)
+		size += len_fec_tlv(&nm->fec);
 	if (nm->flags & F_NOTIF_RETURNED_TLVS)
 		size += TLV_HDR_SIZE * 2 + nm->rtlvs.length;
 
@@ -204,7 +196,9 @@ recv_notification(struct nbr *nbr, char *buf, uint16_t len)
 		len -= tlv_len;
 	}
 
-	if (nm.status_code == S_PW_STATUS) {
+	/* sanity checks */
+	switch (nm.status_code) {
+	case S_PW_STATUS:
 		if (!(nm.flags & (F_NOTIF_PW_STATUS|F_NOTIF_FEC))) {
 			send_notification(nbr->tcp, S_MISS_MSG,
 			    msg.id, msg.type);
@@ -219,6 +213,21 @@ recv_notification(struct nbr *nbr, char *buf, uint16_t len)
 			    msg.id, msg.type);
 			return (-1);
 		}
+		break;
+	case S_ENDOFLIB:
+		if (!(nm.flags & F_NOTIF_FEC)) {
+			send_notification(nbr->tcp, S_MISS_MSG,
+			    msg.id, msg.type);
+			return (-1);
+		}
+		if (nm.fec.type != MAP_TYPE_TYPED_WCARD) {
+			send_notification(nbr->tcp, S_BAD_TLV_VAL,
+			    msg.id, msg.type);
+			return (-1);
+		}
+		break;
+	default:
+		break;
 	}
 
 	log_msg_notification(0, nbr, &nm);
@@ -231,9 +240,16 @@ recv_notification(struct nbr *nbr, char *buf, uint16_t len)
 		return (-1);
 	}
 
-	if (nm.status_code == S_PW_STATUS)
+	/* lde needs to know about a few notification messages */
+	switch (nm.status_code) {
+	case S_PW_STATUS:
+	case S_ENDOFLIB:
 		ldpe_imsg_compose_lde(IMSG_NOTIFICATION, nbr->peerid, 0,
 		    &nm, sizeof(nm));
+		break;
+	default:
+		break;
+	}
 
 	return (0);
 }