Implement support for the Configuration Sequence Number TLV.

The Configuration Sequence Number optional TLV is documented in RFC 5036,
pages 53 and 54.

Fixes IxANVL LDP test 23.10.

5 files changed, 23 insertions, 7 deletions

diff --git a/usr.sbin/ldpd/hello.c b/usr.sbin/ldpd/hello.c
index c8ae8d205b3..42278036f89 100644
--- a/usr.sbin/ldpd/hello.c
+++ b/usr.sbin/ldpd/hello.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: hello.c,v 1.48 2016/06/13 20:13:34 renato Exp $ */
+/*	$OpenBSD: hello.c,v 1.49 2016/06/13 23:01:37 renato Exp $ */
 
 /*
  * Copyright (c) 2013, 2016 Renato Westphal <renato@openbsd.org>
@@ -88,6 +88,7 @@ send_hello(enum hello_type type, struct iface_af *ia, struct tnbr *tnbr)
 	default:
 		fatalx("send_hello: unknown af");
 	}
+	size += sizeof(struct hello_prms_opt4_tlv);
 	if (ldp_is_dual_stack(leconf))
 		size += sizeof(struct hello_prms_opt4_tlv);
 
@@ -119,6 +120,9 @@ send_hello(enum hello_type type, struct iface_af *ia, struct tnbr *tnbr)
 		fatalx("send_hello: unknown af");
 	}
 
+	gen_opt4_hello_prms_tlv(buf, TLV_TYPE_CONFIG,
+	    htonl(global.conf_seqnum));
+
    	/*
 	 * RFC 7552 - Section 6.1.1:
 	 * "A Dual-stack LSR (i.e., an LSR supporting Dual-stack LDP for a peer)
@@ -145,7 +149,7 @@ recv_hello(struct in_addr lsr_id, struct ldp_msg *lm, int af,
 	int			 ds_tlv;
 	union ldpd_addr		 trans_addr;
 	uint32_t		 scope_id = 0;
-	uint32_t		 conf_number;
+	uint32_t		 conf_seqnum;
 	uint16_t		 trans_pref;
 	int			 r;
 	struct hello_source	 source;
@@ -178,7 +182,7 @@ recv_hello(struct in_addr lsr_id, struct ldp_msg *lm, int af,
 	len -= r;
 
 	r = tlv_decode_opt_hello_prms(buf, len, &tlvs_rcvd, af, &trans_addr,
-	    &conf_number, &trans_pref);
+	    &conf_seqnum, &trans_pref);
 	if (r == -1) {
 		log_debug("%s: lsr-id %s: failed to decode optional params",
 		    __func__, inet_ntoa(lsr_id));
@@ -353,6 +357,14 @@ recv_hello(struct in_addr lsr_id, struct ldp_msg *lm, int af,
 	    (trans_pref == DUAL_STACK_LDPOV6 && af != AF_INET6))))
 		nbr = nbr_new(lsr_id, af, ds_tlv, &trans_addr, scope_id);
 
+	/* update neighbor's configuration sequence number */
+	if (nbr && (tlvs_rcvd & F_HELLO_TLV_RCVD_CONF)) {
+		if (conf_seqnum > nbr->conf_seqnum &&
+		    nbr_pending_idtimer(nbr))
+			nbr_stop_idtimer(nbr);
+		nbr->conf_seqnum = conf_seqnum;
+	}
+
 	/* always update the holdtime to properly handle runtime changes */
 	switch (source.type) {
 	case HELLO_LINK:
diff --git a/usr.sbin/ldpd/ldpd.h b/usr.sbin/ldpd/ldpd.h
index b02eab3c013..3c59cc19783 100644
--- a/usr.sbin/ldpd/ldpd.h
+++ b/usr.sbin/ldpd/ldpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldpd.h,v 1.76 2016/05/23 19:20:55 renato Exp $ */
+/*	$OpenBSD: ldpd.h,v 1.77 2016/06/13 23:01:37 renato Exp $ */
 
 /*
  * Copyright (c) 2013, 2016 Renato Westphal <renato@openbsd.org>
@@ -396,6 +396,7 @@ struct ldpd_global {
 	time_t			 uptime;
 	struct ldpd_af_global	 ipv4;
 	struct ldpd_af_global	 ipv6;
+	uint32_t		 conf_seqnum;
 	int			 pfkeysock;
 	struct if_addr_head	 addr_list;
 	LIST_HEAD(, adj)	 adj_list;
diff --git a/usr.sbin/ldpd/ldpe.c b/usr.sbin/ldpd/ldpe.c
index 50b051d277f..51fe0b9b864 100644
--- a/usr.sbin/ldpd/ldpe.c
+++ b/usr.sbin/ldpd/ldpe.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldpe.c,v 1.65 2016/06/13 20:15:58 renato Exp $ */
+/*	$OpenBSD: ldpe.c,v 1.66 2016/06/13 23:01:37 renato Exp $ */
 
 /*
  * Copyright (c) 2013, 2016 Renato Westphal <renato@openbsd.org>
@@ -438,6 +438,7 @@ ldpe_dispatch_main(int fd, short event, void *bula)
 		case IMSG_RECONF_END:
 			merge_config(leconf, nconf);
 			nconf = NULL;
+			global.conf_seqnum++;
 			break;
 		case IMSG_CTL_KROUTE:
 		case IMSG_CTL_KROUTE_ADDR:
diff --git a/usr.sbin/ldpd/ldpe.h b/usr.sbin/ldpd/ldpe.h
index 62341870b52..dfdb19f3a99 100644
--- a/usr.sbin/ldpd/ldpe.h
+++ b/usr.sbin/ldpd/ldpe.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldpe.h,v 1.60 2016/06/13 20:19:40 renato Exp $ */
+/*	$OpenBSD: ldpe.h,v 1.61 2016/06/13 23:01:37 renato Exp $ */
 
 /*
  * Copyright (c) 2013, 2016 Renato Westphal <renato@openbsd.org>
@@ -89,6 +89,7 @@ struct nbr {
 	time_t			 uptime;
 	int			 fd;
 	int			 state;
+	uint32_t		 conf_seqnum;
 	int			 idtimer_cnt;
 	uint16_t		 keepalive;
 	uint16_t		 max_pdu_len;
diff --git a/usr.sbin/ldpd/neighbor.c b/usr.sbin/ldpd/neighbor.c
index 4b607c0ce3f..8f8cf4fe003 100644
--- a/usr.sbin/ldpd/neighbor.c
+++ b/usr.sbin/ldpd/neighbor.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: neighbor.c,v 1.73 2016/06/13 20:19:40 renato Exp $ */
+/*	$OpenBSD: neighbor.c,v 1.74 2016/06/13 23:01:37 renato Exp $ */
 
 /*
  * Copyright (c) 2013, 2016 Renato Westphal <renato@openbsd.org>
@@ -244,6 +244,7 @@ nbr_new(struct in_addr id, int af, int ds_tlv, union ldpd_addr *addr,
 	nbr->laddr = (ldp_af_conf_get(leconf, af))->trans_addr;
 	nbr->raddr = *addr;
 	nbr->raddr_scope = scope_id;
+	nbr->conf_seqnum = 0;
 
 	LIST_FOREACH(adj, &global.adj_list, global_entry) {
 		if (adj->lsr_id.s_addr == nbr->id.s_addr) {