so far, bgpd was hardcoded to use rtable 0 for nexthop verification.

instead, use the rtable bgpd was started in (route -T <n> exec / rc.d
daemon_rtable) for nexthop verification and as default Adj-RIB-In and
Loc-RIB. This allows multiple bgpds in different rdomains on the same
machine - bgp router virtualization if you like buzzwords.
initial version written under contract more than a year ago, it took us
a while to wrap our brains around the bgpd <-> rdomain interactions -
1) RIBs, 2) nexthop verification and 3) tcp sockets.
ok & input phessler claudio benno

5 files changed, 37 insertions, 20 deletions

diff --git a/usr.sbin/bgpd/bgpd.c b/usr.sbin/bgpd/bgpd.c
index ede5967246a..110f699f0c7 100644
--- a/usr.sbin/bgpd/bgpd.c
+++ b/usr.sbin/bgpd/bgpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpd.c,v 1.188 2017/01/24 04:22:42 benno Exp $ */
+/*	$OpenBSD: bgpd.c,v 1.189 2017/05/28 15:16:33 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -603,8 +603,8 @@ dispatch_imsg(struct imsgbuf *ibuf, int idx, struct bgpd_config *conf)
 			else if (imsg.hdr.len != IMSG_HEADER_SIZE +
 			    sizeof(struct bgpd_addr))
 				log_warnx("wrong imsg len");
-			else if (kr_nexthop_add(imsg.hdr.peerid, imsg.data) ==
-			    -1)
+			else if (kr_nexthop_add(imsg.hdr.peerid, imsg.data,
+			    conf) == -1)
 				rv = -1;
 			break;
 		case IMSG_NEXTHOP_REMOVE:
@@ -614,7 +614,8 @@ dispatch_imsg(struct imsgbuf *ibuf, int idx, struct bgpd_config *conf)
 			    sizeof(struct bgpd_addr))
 				log_warnx("wrong imsg len");
 			else
-				kr_nexthop_delete(imsg.hdr.peerid, imsg.data);
+				kr_nexthop_delete(imsg.hdr.peerid, imsg.data,
+				    conf);
 			break;
 		case IMSG_PFTABLE_ADD:
 			if (idx != PFD_PIPE_ROUTE)
diff --git a/usr.sbin/bgpd/bgpd.h b/usr.sbin/bgpd/bgpd.h
index 8f1cd1e123b..3bb4602e6a4 100644
--- a/usr.sbin/bgpd/bgpd.h
+++ b/usr.sbin/bgpd/bgpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpd.h,v 1.305 2017/05/28 12:21:36 claudio Exp $ */
+/*	$OpenBSD: bgpd.h,v 1.306 2017/05/28 15:16:33 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -220,6 +220,7 @@ struct bgpd_config {
 	char					*rcsock;
 	int					 flags;
 	int					 log;
+	u_int					 default_tableid;
 	u_int32_t				 bgpid;
 	u_int32_t				 clusterid;
 	u_int32_t				 as;
@@ -1011,8 +1012,10 @@ void		 kr_fib_decouple(u_int, u_int8_t);
 void		 kr_fib_decouple_all(u_int8_t);
 void		 kr_fib_update_prio_all(u_int8_t);
 int		 kr_dispatch_msg(void);
-int		 kr_nexthop_add(u_int32_t, struct bgpd_addr *);
-void		 kr_nexthop_delete(u_int32_t, struct bgpd_addr *);
+int		 kr_nexthop_add(u_int32_t, struct bgpd_addr *,
+		    struct bgpd_config *);
+void		 kr_nexthop_delete(u_int32_t, struct bgpd_addr *,
+		    struct bgpd_config *);
 void		 kr_show_route(struct imsg *);
 void		 kr_ifinfo(char *);
 int		 kr_net_reload(u_int, struct network_head *);
diff --git a/usr.sbin/bgpd/config.c b/usr.sbin/bgpd/config.c
index adbfaf380ee..8d0f34e2653 100644
--- a/usr.sbin/bgpd/config.c
+++ b/usr.sbin/bgpd/config.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: config.c,v 1.65 2017/01/24 04:22:42 benno Exp $ */
+/*	$OpenBSD: config.c,v 1.66 2017/05/28 15:16:33 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004, 2005 Henning Brauer <henning@openbsd.org>
@@ -52,6 +52,7 @@ new_config(void)
 	conf->min_holdtime = MIN_HOLDTIME;
 	conf->bgpid = get_bgpid();
 	conf->fib_priority = RTP_BGP;
+	conf->default_tableid = getrtable();
 
 	if ((conf->csock = strdup(SOCKET_NAME)) == NULL)
 		fatal(NULL);
diff --git a/usr.sbin/bgpd/kroute.c b/usr.sbin/bgpd/kroute.c
index 36926dd2fd5..138f7684a2d 100644
--- a/usr.sbin/bgpd/kroute.c
+++ b/usr.sbin/bgpd/kroute.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kroute.c,v 1.212 2017/03/28 05:04:09 claudio Exp $ */
+/*	$OpenBSD: kroute.c,v 1.213 2017/05/28 15:16:33 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -875,11 +875,14 @@ kr_dispatch_msg(void)
 }
 
 int
-kr_nexthop_add(u_int rtableid, struct bgpd_addr *addr)
+kr_nexthop_add(u_int rtableid, struct bgpd_addr *addr, struct bgpd_config *conf)
 {
 	struct ktable		*kt;
 	struct knexthop_node	*h;
 
+	if (rtableid == 0)
+		rtableid = conf->default_tableid;
+
 	if ((kt = ktable_get(rtableid)) == NULL) {
 		log_warnx("kr_nexthop_add: non-existent rtableid %d", rtableid);
 		return (0);
@@ -902,11 +905,15 @@ kr_nexthop_add(u_int rtableid, struct bgpd_addr *addr)
 }
 
 void
-kr_nexthop_delete(u_int rtableid, struct bgpd_addr *addr)
+kr_nexthop_delete(u_int rtableid, struct bgpd_addr *addr,
+    struct bgpd_config *conf)
 {
 	struct ktable		*kt;
 	struct knexthop_node	*kn;
 
+	if (rtableid == 0)
+		rtableid = conf->default_tableid;
+
 	if ((kt = ktable_get(rtableid)) == NULL) {
 		log_warnx("kr_nexthop_delete: non-existent rtableid %d",
 		    rtableid);
diff --git a/usr.sbin/bgpd/parse.y b/usr.sbin/bgpd/parse.y
index ad567092cc1..44a9df6597a 100644
--- a/usr.sbin/bgpd/parse.y
+++ b/usr.sbin/bgpd/parse.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.y,v 1.305 2017/05/27 18:12:23 phessler Exp $ */
+/*	$OpenBSD: parse.y,v 1.306 2017/05/28 15:16:33 henning Exp $ */
 
 /*
  * Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -454,7 +454,7 @@ conf_main	: AS as4number		{
 				conf->flags &= ~BGPD_FLAG_NO_EVALUATE;
 		}
 		| RDE RIB STRING {
-			if (add_rib($3, 0, F_RIB_NOFIB)) {
+			if (add_rib($3, conf->default_tableid, F_RIB_NOFIB)) {
 				free($3);
 				YYERROR;
 			}
@@ -466,7 +466,8 @@ conf_main	: AS as4number		{
 				yyerror("bad rde rib definition");
 				YYERROR;
 			}
-			if (add_rib($3, 0, F_RIB_NOFIB | F_RIB_NOEVALUATE)) {
+			if (add_rib($3, conf->default_tableid,
+			    F_RIB_NOFIB | F_RIB_NOEVALUATE)) {
 				free($3);
 				YYERROR;
 			}
@@ -2823,8 +2824,9 @@ parse_config(char *filename, struct bgpd_config *xconf, struct peer **xpeers)
 
 	netconf = &conf->networks;
 
-	add_rib("Adj-RIB-In", 0, F_RIB_NOFIB | F_RIB_NOEVALUATE);
-	add_rib("Loc-RIB", 0, F_RIB_LOCAL);
+	add_rib("Adj-RIB-In", conf->default_tableid,
+	    F_RIB_NOFIB | F_RIB_NOEVALUATE);
+	add_rib("Loc-RIB", conf->default_tableid, F_RIB_LOCAL);
 
 	if ((file = pushfile(filename, 1)) == NULL) {
 		free(conf);
@@ -3373,7 +3375,7 @@ int
 add_rib(char *name, u_int rtableid, u_int16_t flags)
 {
 	struct rde_rib	*rr;
-	u_int		 rdom;
+	u_int		 rdom, default_rdom;
 
 	if ((rr = find_rib(name)) == NULL) {
 		if ((rr = calloc(1, sizeof(*rr))) == NULL) {
@@ -3394,9 +3396,12 @@ add_rib(char *name, u_int rtableid, u_int16_t flags)
 			free(rr);
 			return (-1);
 		}
-		if (rdom != 0) {
-			yyerror("rtable %u does not belong to rdomain 0",
-			    rtableid);
+		if (ktable_exists(conf->default_tableid, &default_rdom) != 1)
+			fatal("default rtable %u does not exist",
+			    conf->default_tableid);
+		if (rdom != default_rdom) {
+			log_warnx("rtable %u does not belong to rdomain %u",
+			    rtableid, default_rdom);
 			free(rr);
 			return (-1);
 		}