Enable changing the router-id via config reload.

Now ldpd can start without a router-id, since it can be set later. Since
a router-id of 0.0.0.0 is invalid, interfaces and targeted-neighbors
will check for a valid router-id in order to be activated.

When the router-id is changed, all the neighborships are reset.

6 files changed, 49 insertions, 18 deletions

diff --git a/usr.sbin/ldpd/adjacency.c b/usr.sbin/ldpd/adjacency.c
index 505acfb8d5d..3596315fd74 100644
--- a/usr.sbin/ldpd/adjacency.c
+++ b/usr.sbin/ldpd/adjacency.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: adjacency.c,v 1.16 2016/05/23 18:33:56 renato Exp $ */
+/*	$OpenBSD: adjacency.c,v 1.17 2016/05/23 18:41:59 renato Exp $ */
 
 /*
  * Copyright (c) 2009 Michele Marchetto <michele@openbsd.org>
@@ -213,15 +213,20 @@ tnbr_check(struct tnbr *tnbr)
 void
 tnbr_update(struct tnbr *tnbr)
 {
-	int			 socket_ok;
+	int			 socket_ok, rtr_id_ok;
 
 	if (global.ldp_edisc_socket != -1)
 		socket_ok = 1;
 	else
 		socket_ok = 0;
 
+	if (leconf->rtr_id.s_addr != INADDR_ANY)
+		rtr_id_ok = 1;
+	else
+		rtr_id_ok = 0;
+
 	if (tnbr->state == TNBR_STA_DOWN) {
-		if (!socket_ok)
+		if (!socket_ok || !rtr_id_ok)
 			return;
 
 		tnbr->state = TNBR_STA_ACTIVE;
@@ -230,7 +235,7 @@ tnbr_update(struct tnbr *tnbr)
 		evtimer_set(&tnbr->hello_timer, tnbr_hello_timer, tnbr);
 		tnbr_start_hello_timer(tnbr);
 	} else if (tnbr->state == TNBR_STA_ACTIVE) {
-		if (socket_ok)
+		if (socket_ok && rtr_id_ok)
 			return;
 
 		tnbr->state = TNBR_STA_DOWN;
diff --git a/usr.sbin/ldpd/interface.c b/usr.sbin/ldpd/interface.c
index 9d26b1b12dc..22a5ea17f84 100644
--- a/usr.sbin/ldpd/interface.c
+++ b/usr.sbin/ldpd/interface.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: interface.c,v 1.39 2016/05/23 18:40:15 renato Exp $ */
+/*	$OpenBSD: interface.c,v 1.40 2016/05/23 18:41:59 renato Exp $ */
 
 /*
  * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
@@ -239,7 +239,7 @@ if_reset(struct iface *iface)
 int
 if_update(struct iface *iface)
 {
-	int			 link_ok, addr_ok = 0, socket_ok;
+	int			 link_ok, addr_ok = 0, socket_ok, rtr_id_ok;
 	int			 ret;
 
 	link_ok = (iface->flags & IFF_UP) &&
@@ -252,15 +252,20 @@ if_update(struct iface *iface)
 	else
 		socket_ok = 0;
 
+	if (leconf->rtr_id.s_addr != INADDR_ANY)
+		rtr_id_ok = 1;
+	else
+		rtr_id_ok = 0;
+
 	if (iface->state == IF_STA_DOWN) {
-		if (!link_ok || !addr_ok || !socket_ok)
+		if (!link_ok || !addr_ok || !socket_ok || !rtr_id_ok)
 			return (0);
 
 
 		iface->state = IF_STA_ACTIVE;
 		ret = if_start(iface);
 	} else {
-		if (link_ok && addr_ok && socket_ok)
+		if (link_ok && addr_ok && socket_ok && rtr_id_ok)
 			return (0);
 
 		iface->state = IF_STA_DOWN;
diff --git a/usr.sbin/ldpd/ldpd.c b/usr.sbin/ldpd/ldpd.c
index 935257ad8d2..29d66ed65f3 100644
--- a/usr.sbin/ldpd/ldpd.c
+++ b/usr.sbin/ldpd/ldpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldpd.c,v 1.41 2016/05/23 18:40:15 renato Exp $ */
+/*	$OpenBSD: ldpd.c,v 1.42 2016/05/23 18:41:59 renato Exp $ */
 
 /*
  * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
@@ -667,7 +667,19 @@ merge_global(struct ldpd_conf *conf, struct ldpd_conf *xconf)
 	struct nbr_params	*nbrp;
 	int			 egress_label_changed = 0;
 
-	/* change of rtr_id needs a restart */
+	/* change of router-id requires resetting all neighborships */
+	if (conf->rtr_id.s_addr != xconf->rtr_id.s_addr) {
+		if (ldpd_process == PROC_LDP_ENGINE) {
+			ldpe_reset_nbrs();
+			if (conf->rtr_id.s_addr == INADDR_ANY ||
+			    xconf->rtr_id.s_addr == INADDR_ANY) {
+				if_update_all();
+				tnbr_update_all();
+			}
+		}
+		conf->rtr_id = xconf->rtr_id;
+	}
+
 	if (conf->keepalive != xconf->keepalive) {
 		conf->keepalive = xconf->keepalive;
 		if (ldpd_process == PROC_LDP_ENGINE)
diff --git a/usr.sbin/ldpd/ldpe.c b/usr.sbin/ldpd/ldpe.c
index 623632d828c..55ebe250fbc 100644
--- a/usr.sbin/ldpd/ldpe.c
+++ b/usr.sbin/ldpd/ldpe.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldpe.c,v 1.54 2016/05/23 18:40:15 renato Exp $ */
+/*	$OpenBSD: ldpe.c,v 1.55 2016/05/23 18:41:59 renato Exp $ */
 
 /*
  * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
@@ -624,6 +624,15 @@ ldpe_close_sockets(void)
 }
 
 void
+ldpe_reset_nbrs(void)
+{
+	struct nbr		*nbr;
+
+	RB_FOREACH(nbr, nbr_id_head, &nbrs_by_id)
+		session_shutdown(nbr, S_SHUTDOWN, 0, 0);
+}
+
+void
 ldpe_remove_dynamic_tnbrs(void)
 {
 	struct tnbr		*tnbr, *safe;
diff --git a/usr.sbin/ldpd/ldpe.h b/usr.sbin/ldpd/ldpe.h
index ac8a04631ff..d56d2477ddb 100644
--- a/usr.sbin/ldpd/ldpe.h
+++ b/usr.sbin/ldpd/ldpe.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldpe.h,v 1.49 2016/05/23 18:40:15 renato Exp $ */
+/*	$OpenBSD: ldpe.h,v 1.50 2016/05/23 18:41:59 renato Exp $ */
 
 /*
  * Copyright (c) 2004, 2005, 2008 Esben Norby <norby@openbsd.org>
@@ -163,6 +163,7 @@ void		 ldpe_dispatch_lde(int, short, void *);
 void		 ldpe_dispatch_pfkey(int, short, void *);
 void		 ldpe_setup_sockets(int, int, int);
 void		 ldpe_close_sockets(void);
+void		 ldpe_reset_nbrs(void);
 void		 ldpe_remove_dynamic_tnbrs(void);
 void		 ldpe_stop_init_backoff(void);
 void		 ldpe_iface_ctl(struct ctl_conn *, unsigned int);
diff --git a/usr.sbin/ldpd/parse.y b/usr.sbin/ldpd/parse.y
index fbaa1e679b9..cdfcb77c45d 100644
--- a/usr.sbin/ldpd/parse.y
+++ b/usr.sbin/ldpd/parse.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.y,v 1.47 2016/05/23 18:36:55 renato Exp $ */
+/*	$OpenBSD: parse.y,v 1.48 2016/05/23 18:41:59 renato Exp $ */
 
 /*
  * Copyright (c) 2004, 2005, 2008 Esben Norby <norby@openbsd.org>
@@ -1330,8 +1330,10 @@ get_rtr_id(void)
 
 	localnet = htonl(INADDR_LOOPBACK & IN_CLASSA_NET);
 
-	if (getifaddrs(&ifap) == -1)
-		fatal("getifaddrs");
+	if (getifaddrs(&ifap) == -1) {
+		log_warn("getifaddrs");
+		return (0);
+	}
 
 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 		if (strncmp(ifa->ifa_name, "carp", 4) == 0)
@@ -1346,9 +1348,6 @@ get_rtr_id(void)
 	}
 	freeifaddrs(ifap);
 
-	if (ip == 0)
-		fatal("router-id is 0.0.0.0");
-
 	return (ip);
 }