rework bgpd's handling of listening sockets. instead of one for each

supported address familiy, keep a tailq of an arbitary number of them.
the new struct listen_addr contains the sockaddr and the fd.
this fixes quite some nasty behaviour which was a consequence of the previous
model.
looks right deraadt@, and discussed with claudio

8 files changed, 295 insertions, 106 deletions

diff --git a/usr.sbin/bgpd/bgpd.c b/usr.sbin/bgpd/bgpd.c
index 6cd92f39e83..bce647303fc 100644
--- a/usr.sbin/bgpd/bgpd.c
+++ b/usr.sbin/bgpd/bgpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpd.c,v 1.94 2004/05/21 11:48:56 claudio Exp $ */
+/*	$OpenBSD: bgpd.c,v 1.95 2004/06/06 17:38:10 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -100,6 +100,7 @@ main(int argc, char *argv[])
 	struct network		*net;
 	struct filter_rule	*r;
 	struct mrt		*(mrt[POLL_MAX]), *m;
+	struct listen_addr	*la;
 	struct pollfd		 pfd[POLL_MAX];
 	pid_t			 io_pid = 0, rde_pid = 0, pid;
 	char			*conffile;
@@ -228,6 +229,11 @@ main(int argc, char *argv[])
 		free(r);
 	}
 
+	while ((la = TAILQ_FIRST(conf.listen_addrs)) != NULL) {
+		TAILQ_REMOVE(conf.listen_addrs, la, entry);
+		free(la);
+	}
+
 	while (quit == 0) {
 		pfd[PFD_PIPE_SESSION].fd = ibuf_se.fd;
 		pfd[PFD_PIPE_SESSION].events = POLLIN;
@@ -368,6 +374,7 @@ reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_head *mrt_l,
 	struct network		*n;
 	struct peer		*p;
 	struct filter_rule	*r;
+	struct listen_addr	*la;
 
 	if (parse_config(conffile, conf, mrt_l, peer_l, &net_l, rules_l)) {
 		log_warnx("config file %s has errors, not reloading",
@@ -399,6 +406,16 @@ reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_head *mrt_l,
 		TAILQ_REMOVE(rules_l, r, entries);
 		free(r);
 	}
+	while ((la = TAILQ_FIRST(conf->listen_addrs)) != NULL) {
+		if (imsg_compose(&ibuf_se, IMSG_RECONF_LISTENER, 0,
+		    la, sizeof(struct listen_addr)) == -1)
+			return (-1);
+		TAILQ_REMOVE(conf->listen_addrs, la, entry);
+		free(la);
+	}
+	free(conf->listen_addrs);
+	conf->listen_addrs = NULL;
+
 	if (imsg_compose(&ibuf_se, IMSG_RECONF_DONE, 0, NULL, 0) == -1 ||
 	    imsg_compose(&ibuf_rde, IMSG_RECONF_DONE, 0, NULL, 0) == -1)
 		return (-1);
diff --git a/usr.sbin/bgpd/bgpd.h b/usr.sbin/bgpd/bgpd.h
index 9ddd92d22c8..967c45d1de2 100644
--- a/usr.sbin/bgpd/bgpd.h
+++ b/usr.sbin/bgpd/bgpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpd.h,v 1.125 2004/05/21 15:36:40 claudio Exp $ */
+/*	$OpenBSD: bgpd.h,v 1.126 2004/06/06 17:38:10 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -108,17 +108,28 @@ struct bgpd_addr {
 #define addr32	ba.addr32
 };
 
+#define DEFAULT_LISTENER	0x01
+
+struct listen_addr {
+	TAILQ_ENTRY(listen_addr)	 entry;
+	struct sockaddr_storage		 sa;
+	int				 fd;
+	enum reconf_action		 reconf;
+	u_int8_t			 flags;
+};
+
+TAILQ_HEAD(listen_addrs, listen_addr);
+
 struct bgpd_config {
-	int			 opts;
-	u_int16_t		 as;
-	u_int32_t		 bgpid;
-	u_int32_t		 clusterid;
-	u_int16_t		 holdtime;
-	u_int16_t		 min_holdtime;
-	int			 flags;
-	int			 log;
-	struct sockaddr_in	 listen_addr;
-	struct sockaddr_in6	 listen6_addr;
+	int					 opts;
+	u_int16_t				 as;
+	u_int32_t				 bgpid;
+	u_int32_t				 clusterid;
+	u_int16_t				 holdtime;
+	u_int16_t				 min_holdtime;
+	int					 flags;
+	int					 log;
+	struct listen_addrs			*listen_addrs;
 };
 
 struct buf_read {
@@ -239,6 +250,7 @@ enum imsg_type {
 	IMSG_RECONF_CONF,
 	IMSG_RECONF_PEER,
 	IMSG_RECONF_FILTER,
+	IMSG_RECONF_LISTENER,
 	IMSG_RECONF_DONE,
 	IMSG_UPDATE,
 	IMSG_UPDATE_ERR,
diff --git a/usr.sbin/bgpd/config.c b/usr.sbin/bgpd/config.c
index 56f801ca75f..151f1f515a7 100644
--- a/usr.sbin/bgpd/config.c
+++ b/usr.sbin/bgpd/config.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: config.c,v 1.37 2004/05/21 15:36:40 claudio Exp $ */
+/*	$OpenBSD: config.c,v 1.38 2004/06/06 17:38:10 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -37,10 +37,11 @@ int		host_v6(const char *, struct bgpd_addr *);
 
 int
 merge_config(struct bgpd_config *xconf, struct bgpd_config *conf,
-    struct peer *peer_l)
+    struct peer *peer_l, struct listen_addrs *listen_addrs)
 {
-	struct peer	*p;
-	int		 errs = 0;
+	struct peer				*p;
+	struct listen_addr			*la;
+	int					 errs = 0;
 
 	/* preserve cmd line opts */
 	conf->opts = xconf->opts;
@@ -75,8 +76,18 @@ merge_config(struct bgpd_config *xconf, struct bgpd_config *conf,
 		}
 	}
 
+	if (xconf->listen_addrs != NULL) {
+		while ((la = TAILQ_FIRST(xconf->listen_addrs)) != NULL) {
+			TAILQ_REMOVE(xconf->listen_addrs, la, entry);
+			free(la);
+		}
+		free(xconf->listen_addrs);
+	}
+
 	memcpy(xconf, conf, sizeof(struct bgpd_config));
 
+	xconf->listen_addrs = listen_addrs;
+
 	return (errs);
 }
 
diff --git a/usr.sbin/bgpd/parse.y b/usr.sbin/bgpd/parse.y
index 6e645c94512..846b0bb6ff1 100644
--- a/usr.sbin/bgpd/parse.y
+++ b/usr.sbin/bgpd/parse.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.y,v 1.112 2004/05/21 15:36:40 claudio Exp $ */
+/*	$OpenBSD: parse.y,v 1.113 2004/06/06 17:38:10 henning Exp $ */
 
 /*
  * Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -45,6 +45,7 @@ static struct peer		*peer_l, *peer_l_old;
 static struct peer		*curpeer;
 static struct peer		*curgroup;
 static struct filter_head	*filter_l;
+static struct listen_addrs	*listen_addrs;
 static FILE			*fin = NULL;
 static int			 lineno = 1;
 static int			 errors = 0;
@@ -226,20 +227,37 @@ conf_main	: AS asnumber		{
 			conf->min_holdtime = $3;
 		}
 		| LISTEN ON address	{
+			struct listen_addr	*la;
+			struct sockaddr_in	*in;
+			struct sockaddr_in6	*in6;
+
+			if ((la = calloc(1, sizeof(struct listen_addr))) ==
+			    NULL)
+				fatal("parse conf_main listen on calloc");
+
+			la->fd = -1;
+			la->sa.ss_family = $3.af;
 			switch ($3.af) {
 			case AF_INET:
-				conf->listen_addr.sin_addr.s_addr =
-				    $3.v4.s_addr;
+				la->sa.ss_len = sizeof(struct sockaddr_in);
+				in = (struct sockaddr_in *)&la->sa;
+				in->sin_addr.s_addr = $3.v4.s_addr;
+				in->sin_port = htons(BGP_PORT);
 				break;
 			case AF_INET6:
-				memcpy(&conf->listen6_addr.sin6_addr, &$3.v6,
-				    sizeof(conf->listen6_addr.sin6_addr));
+				la->sa.ss_len = sizeof(struct sockaddr_in6);
+				in6 = (struct sockaddr_in6 *)&la->sa;
+				memcpy(&in6->sin6_addr, &$3.v6,
+				    sizeof(in6->sin6_addr));
+				in6->sin6_port = htons(BGP_PORT);
 				break;
 			default:
 				yyerror("king bula does not like family %u",
 				    $3.af);
 				YYERROR;
 			}
+
+			TAILQ_INSERT_TAIL(listen_addrs, la, entry);
 		}
 		| FIBUPDATE yesno		{
 			if ($2 == 0)
@@ -1279,9 +1297,12 @@ parse_config(char *filename, struct bgpd_config *xconf,
 		fatal(NULL);
 	if ((mrtconf = calloc(1, sizeof(struct mrt_head))) == NULL)
 		fatal(NULL);
+	if ((listen_addrs = calloc(1, sizeof(struct listen_addrs))) == NULL)
+		fatal(NULL);
 	LIST_INIT(mrtconf);
 	netconf = nc;
 	TAILQ_INIT(netconf);
+	TAILQ_INIT(listen_addrs);
 
 	peer_l = NULL;
 	peer_l_old = *xpeers;
@@ -1293,16 +1314,6 @@ parse_config(char *filename, struct bgpd_config *xconf,
 	filter_l = xfilter_l;
 	TAILQ_INIT(filter_l);
 
-	conf->listen_addr.sin_len = sizeof(conf->listen_addr);
-	conf->listen_addr.sin_family = AF_INET;
-	conf->listen_addr.sin_addr.s_addr = INADDR_ANY;
-	conf->listen_addr.sin_port = htons(BGP_PORT);
-
-	bzero(&conf->listen6_addr, sizeof(conf->listen6_addr));
-	conf->listen6_addr.sin6_len = sizeof(conf->listen6_addr);
-	conf->listen6_addr.sin6_family = AF_INET6;
-	conf->listen6_addr.sin6_port = htons(BGP_PORT);
-
 	if ((fin = fopen(filename, "r")) == NULL) {
 		warn("%s", filename);
 		free(conf);
@@ -1336,7 +1347,7 @@ parse_config(char *filename, struct bgpd_config *xconf,
 		}
 	}
 
-	errors += merge_config(xconf, conf, peer_l);
+	errors += merge_config(xconf, conf, peer_l, listen_addrs);
 	errors += mrt_mergeconfig(xmconf, mrtconf);
 	*xpeers = peer_l;
 
diff --git a/usr.sbin/bgpd/printconf.c b/usr.sbin/bgpd/printconf.c
index dbe220be40b..6d7bcb86f38 100644
--- a/usr.sbin/bgpd/printconf.c
+++ b/usr.sbin/bgpd/printconf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: printconf.c,v 1.20 2004/05/08 19:17:20 henning Exp $	*/
+/*	$OpenBSD: printconf.c,v 1.21 2004/06/06 17:38:10 henning Exp $	*/
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -88,8 +88,8 @@ print_set(struct filter_set *set)
 void
 print_mainconf(struct bgpd_config *conf)
 {
-	struct in_addr	ina;
-	struct in6_addr	ina6;
+	struct in_addr		 ina;
+	struct listen_addr	*la;
 
 	printf("AS %u\n", conf->as);
 	ina.s_addr = conf->bgpid;
@@ -110,13 +110,9 @@ print_mainconf(struct bgpd_config *conf)
 	if (conf->log & BGPD_LOG_UPDATES)
 		printf("log updates\n");
 
-	if (conf->listen_addr.sin_addr.s_addr != INADDR_ANY)
-		printf("listen on %s\n", inet_ntoa(conf->listen_addr.sin_addr));
-
-	bzero(&ina6, sizeof(ina6));
-	if (bcmp(&ina6, &conf->listen6_addr.sin6_addr, sizeof(ina6)))
+	TAILQ_FOREACH(la, conf->listen_addrs, entry)
 		printf("listen on %s\n",
-		    log_sockaddr((struct sockaddr *)&conf->listen6_addr));
+		    log_sockaddr((struct sockaddr *)&la->sa));
 }
 
 void
diff --git a/usr.sbin/bgpd/rde.c b/usr.sbin/bgpd/rde.c
index 87f3c8f6fae..6b183441ff1 100644
--- a/usr.sbin/bgpd/rde.c
+++ b/usr.sbin/bgpd/rde.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde.c,v 1.115 2004/05/21 15:36:40 claudio Exp $ */
+/*	$OpenBSD: rde.c,v 1.116 2004/06/06 17:38:10 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -104,11 +104,12 @@ rde_main(struct bgpd_config *config, struct network_head *net_l,
     struct filter_head *rules, struct mrt_head *mrt_l,
     int pipe_m2r[2], int pipe_s2r[2])
 {
-	pid_t		 pid;
-	struct passwd	*pw;
-	struct mrt	*m;
-	struct pollfd	 pfd[2];
-	int		 nfds;
+	pid_t			 pid;
+	struct passwd		*pw;
+	struct mrt		*m;
+	struct listen_addr	*la;
+	struct pollfd		 pfd[2];
+	int			 nfds;
 
 	switch (pid = fork()) {
 	case -1:
@@ -150,11 +151,16 @@ rde_main(struct bgpd_config *config, struct network_head *net_l,
 	imsg_init(&ibuf_se, pipe_s2r[1]);
 	imsg_init(&ibuf_main, pipe_m2r[1]);
 
-	/* main mrt list is not used in the SE */
+	/* main mrt list and listener list are not used in the SE */
 	while ((m = LIST_FIRST(mrt_l)) != NULL) {
 		LIST_REMOVE(m, list);
 		free(m);
 	}
+	while ((la = TAILQ_FIRST(config->listen_addrs)) != NULL) {
+		TAILQ_REMOVE(config->listen_addrs, la, entry);
+		free(la);
+	}
+	free(config->listen_addrs);
 
 	pt_init();
 	path_init(pathhashsize);
diff --git a/usr.sbin/bgpd/session.c b/usr.sbin/bgpd/session.c
index 603d68c27ac..9d581aedee6 100644
--- a/usr.sbin/bgpd/session.c
+++ b/usr.sbin/bgpd/session.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: session.c,v 1.172 2004/05/28 18:39:09 henning Exp $ */
+/*	$OpenBSD: session.c,v 1.173 2004/06/06 17:38:10 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -44,15 +44,13 @@
 #include "mrt.h"
 #include "session.h"
 
-#define	PFD_LISTEN	0
-#define	PFD_LISTEN6	1
-#define PFD_PIPE_MAIN	2
-#define PFD_PIPE_ROUTE	3
-#define	PFD_SOCK_CTL	4
-#define PFD_PEERS_START	5
+#define PFD_PIPE_MAIN		0
+#define PFD_PIPE_ROUTE		1
+#define	PFD_SOCK_CTL		2
+#define PFD_LISTENERS_START	3
 
 void	session_sighdlr(int);
-int	setup_listener(struct sockaddr *);
+int	setup_listeners(void);
 void	init_conf(struct bgpd_config *);
 void	init_peer(struct peer *);
 int	timer_due(time_t);
@@ -81,6 +79,7 @@ void	session_dispatch_imsg(struct imsgbuf *, int);
 void	session_up(struct peer *);
 void	session_down(struct peer *);
 
+int			 la_cmp(struct listen_addr *, struct listen_addr *);
 struct peer		*getpeerbyip(struct sockaddr *);
 int			 session_match_mask(struct peer *, struct sockaddr *);
 struct peer		*getpeerbyid(u_int32_t);
@@ -91,8 +90,6 @@ struct bgpd_sysdep	 sysdep;
 struct peer		*npeers;
 volatile sig_atomic_t	 session_quit = 0;
 int			 pending_reconf = 0;
-int			 sock = -1;
-int			 sock6 = -1;
 int			 csock = -1;
 struct imsgbuf		 ibuf_rde;
 struct imsgbuf		 ibuf_main;
@@ -111,41 +108,77 @@ session_sighdlr(int sig)
 }
 
 int
-setup_listener(struct sockaddr *sa)
+setup_listeners(void)
 {
-	int	fd, opt;
+	int			 opt;
+	struct listen_addr	*la;
+
+	if (TAILQ_EMPTY(conf->listen_addrs)) {
+		if ((la = calloc(1, sizeof(struct listen_addr))) == NULL)
+			fatal("setup_listeners calloc");
+		la->fd = -1;
+		la->flags = DEFAULT_LISTENER;
+		la->sa.ss_len = sizeof(struct sockaddr_in);
+		((struct sockaddr_in *)&la->sa)->sin_family = AF_INET;
+		((struct sockaddr_in *)&la->sa)->sin_addr.s_addr =
+		    htonl(INADDR_ANY);
+		((struct sockaddr_in *)&la->sa)->sin_port = htons(BGP_PORT);
+		TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry);
+
+		if ((la = calloc(1, sizeof(struct listen_addr))) == NULL)
+			fatal("setup_listeners calloc");
+		la->fd = -1;
+		la->flags = DEFAULT_LISTENER;
+		la->sa.ss_len = sizeof(struct sockaddr_in6);
+		((struct sockaddr_in6 *)&la->sa)->sin6_family = AF_INET6;
+		((struct sockaddr_in6 *)&la->sa)->sin6_port = htons(BGP_PORT);
+		TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry);
+	}
+
+	TAILQ_FOREACH(la, conf->listen_addrs, entry) {
+		la->reconf = RECONF_NONE;
+
+		if (la->fd != -1)
+			continue;
 
-	if (sa->sa_family != AF_INET && sa->sa_family != AF_INET6)
-		fatal("king bula sez: unknown address family");
+		if ((la->fd = socket(la->sa.ss_family, SOCK_STREAM,
+		    IPPROTO_TCP)) == -1)
+			fatal("socket");
 
-	if ((fd = socket(sa->sa_family, SOCK_STREAM, IPPROTO_TCP)) == -1) {
-		log_warn("error setting up %s listener",
-		    sa->sa_family == AF_INET ? "IPv4" : "IPv6");
-		return (fd);
-	}
+		opt = 1;
+		if (setsockopt(la->fd, IPPROTO_TCP, TCP_MD5SIG,
+		    &opt, sizeof(opt)) == -1) {
+			if (errno == ENOPROTOOPT) {	/* system w/o md5sig */
+				log_warnx("md5sig not available, disabling");
+				sysdep.no_md5sig = 1;
+			} else
+				fatal("setsockopt TCP_MD5SIG");
+		}
 
-	opt = 1;
-	if (setsockopt(fd, IPPROTO_TCP, TCP_MD5SIG, &opt, sizeof(opt)) == -1) {
-		if (errno == ENOPROTOOPT) {	/* system w/o md5sig support */
-			log_warnx("md5 signatures not available, disabling");
-			sysdep.no_md5sig = 1;
-		} else
-			fatal("setsockopt TCP_MD5SIG");
-	}
+		if (bind(la->fd, (struct sockaddr *)&la->sa, la->sa.ss_len) ==
+		    -1) {
+			if (errno == EACCES) {
+				log_warnx("can't establish listener on %s",
+				    log_sockaddr((struct sockaddr *)&la->sa));
+				close(la->fd);
+				la->fd = -1;
+				return (-1);
+			} else
+				fatal("bind");
+		}
 
-	if (bind(fd, sa, sa->sa_len)) {
-		close(fd);
-		fatal("bind");
-	}
+		session_socket_blockmode(la->fd, BM_NONBLOCK);
 
-	session_socket_blockmode(fd, BM_NONBLOCK);
+		if (listen(la->fd, MAX_BACKLOG)) {
+			close(la->fd);
+			fatal("listen");
+		}
 
-	if (listen(fd, MAX_BACKLOG)) {
-		close(fd);
-		fatal("listen");
+		log_info("listening on %s",
+		    log_sockaddr((struct sockaddr *)&la->sa));
 	}
 
-	return (fd);
+	return (0);
 }
 
 int
@@ -153,7 +186,7 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
     struct network_head *net_l, struct filter_head *rules,
     struct mrt_head *m_l, int pipe_m2s[2], int pipe_s2r[2])
 {
-	int			 nfds, i, j, timeout, idx_peers;
+	int			 nfds, i, j, timeout, idx_peers, idx_listeners;
 	pid_t			 pid;
 	time_t			 nextaction;
 	struct passwd		*pw;
@@ -164,6 +197,7 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 	struct filter_rule	*r;
 	struct pollfd		 pfd[OPEN_MAX];
 	struct ctl_conn		*ctl_conn;
+	struct listen_addr	*la;
 	short			 events;
 
 	conf = config;
@@ -193,8 +227,7 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 	setproctitle("session engine");
 	bgpd_process = PROC_SE;
 
-	sock = setup_listener((struct sockaddr *)&conf->listen_addr);
-	sock6 = setup_listener((struct sockaddr *)&conf->listen6_addr);
+	setup_listeners();
 
 	if (pfkey_init(&sysdep) == -1)
 		fatalx("pfkey setup failed");
@@ -240,10 +273,6 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 
 	while (session_quit == 0) {
 		bzero(&pfd, sizeof(pfd));
-		pfd[PFD_LISTEN].fd = sock;
-		pfd[PFD_LISTEN].events = POLLIN;
-		pfd[PFD_LISTEN6].fd = sock6;
-		pfd[PFD_LISTEN6].events = POLLIN;
 		pfd[PFD_PIPE_MAIN].fd = ibuf_main.fd;
 		pfd[PFD_PIPE_MAIN].events = POLLIN;
 		if (ibuf_main.w.queued > 0)
@@ -256,7 +285,15 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 		pfd[PFD_SOCK_CTL].events = POLLIN;
 
 		nextaction = time(NULL) + 240;	/* loop every 240s at least */
-		i = PFD_PEERS_START;
+		i = PFD_LISTENERS_START;
+
+		TAILQ_FOREACH(la, conf->listen_addrs, entry) {
+			pfd[i].fd = la->fd;
+			pfd[i].events = POLLIN;
+			i++;
+		}
+
+		idx_listeners = i;
 
 		last = NULL;
 		for (p = peers; p != NULL; p = next) {
@@ -353,16 +390,6 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 			if (errno != EINTR)
 				fatal("poll error");
 
-		if (nfds > 0 && pfd[PFD_LISTEN].revents & POLLIN) {
-			nfds--;
-			session_accept(sock);
-		}
-
-		if (nfds > 0 && pfd[PFD_LISTEN6].revents & POLLIN) {
-			nfds--;
-			session_accept(sock6);
-		}
-
 		if (nfds > 0 && pfd[PFD_PIPE_MAIN].revents & POLLOUT)
 			if (msgbuf_write(&ibuf_main.w) < 0)
 				fatal("pipe write error");
@@ -386,7 +413,14 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 			control_accept(csock);
 		}
 
-		for (j = PFD_PEERS_START; nfds > 0 && j < idx_peers; j++)
+		for (j = PFD_LISTENERS_START; nfds > 0 && j < idx_listeners;
+		    j++)
+			if (pfd[j].revents & POLLIN) {
+				nfds--;
+				session_accept(pfd[j].fd);
+			}
+
+		for (; nfds > 0 && j < idx_peers; j++)
 			nfds -= session_dispatch_msg(&pfd[j], peer_l[j]);
 
 		for (; nfds > 0 && j < i; j++)
@@ -405,6 +439,12 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 		free(mrt);
 	}
 
+	while ((la = TAILQ_FIRST(conf->listen_addrs)) != NULL) {
+		TAILQ_REMOVE(conf->listen_addrs, la, entry);
+		free(la);
+	}
+	free(conf->listen_addrs);
+
 	msgbuf_write(&ibuf_rde.w);
 	msgbuf_clear(&ibuf_rde.w);
 	msgbuf_write(&ibuf_main.w);
@@ -1914,6 +1954,7 @@ session_dispatch_imsg(struct imsgbuf *ibuf, int idx)
 	struct mrt_config	*mrt;
 	struct peer_config	*pconf;
 	struct peer		*p, *next;
+	struct listen_addr	*la, *nla;
 	u_char			*data;
 	enum reconf_action	 reconf;
 	int			 n;
@@ -1940,6 +1981,10 @@ session_dispatch_imsg(struct imsgbuf *ibuf, int idx)
 			    NULL)
 				fatal(NULL);
 			memcpy(nconf, imsg.data, sizeof(struct bgpd_config));
+			if ((nconf->listen_addrs = calloc(1,
+			    sizeof(struct listen_addrs))) == NULL)
+				fatal(NULL);
+			TAILQ_INIT(nconf->listen_addrs);
 			npeers = NULL;
 			init_conf(nconf);
 			pending_reconf = 1;
@@ -1963,6 +2008,29 @@ session_dispatch_imsg(struct imsgbuf *ibuf, int idx)
 			memcpy(&p->conf, pconf, sizeof(struct peer_config));
 			p->conf.reconf_action = reconf;
 			break;
+		case IMSG_RECONF_LISTENER:
+			if (idx != PFD_PIPE_MAIN)
+				fatalx("reconf request not from parent");
+			nla = imsg.data;
+			TAILQ_FOREACH(la, conf->listen_addrs, entry) {
+				if (!la_cmp(la, nla))
+					break;
+			}
+
+			if (la == NULL) {
+				la = calloc(1, sizeof(struct listen_addr));
+				if (la == NULL)
+					fatal(NULL);
+				memcpy(&la->sa, &nla->sa, sizeof(la->sa));
+				la->fd = nla->fd;
+				la->flags = nla->flags;
+				la->reconf = RECONF_REINIT;
+				TAILQ_INSERT_TAIL(nconf->listen_addrs, la,
+				    entry);
+			} else {
+				la->reconf = RECONF_KEEP;
+			}
+			break;
 		case IMSG_RECONF_DONE:
 			if (idx != PFD_PIPE_MAIN)
 				fatalx("reconf request not from parent");
@@ -1972,17 +2040,50 @@ session_dispatch_imsg(struct imsgbuf *ibuf, int idx)
 			conf->holdtime = nconf->holdtime;
 			conf->bgpid = nconf->bgpid;
 			conf->min_holdtime = nconf->min_holdtime;
+
 			/* add new peers */
 			for (p = npeers; p != NULL; p = next) {
 				next = p->next;
 				p->next = peers;
 				peers = p;
 			}
-			/* find peers to be deleted */
+			/* find ones to be deleted */
 			for (p = peers; p != NULL; p = p->next)
 				if (p->conf.reconf_action == RECONF_NONE &&
 				    !p->conf.cloned)
 					p->conf.reconf_action = RECONF_DELETE;
+
+			/* if there are no new listeners, keep default ones */
+			if (TAILQ_EMPTY(nconf->listen_addrs))
+				TAILQ_FOREACH(la, conf->listen_addrs, entry)
+					if (la->flags & DEFAULT_LISTENER)
+						la->reconf = RECONF_KEEP;
+
+			/* delete old listeners */
+			for (la = TAILQ_FIRST(conf->listen_addrs); la != NULL;
+			    la = nla) {
+				nla = TAILQ_NEXT(la, entry);
+				if (la->reconf == RECONF_NONE) {
+					log_info("not listening on %s any more",
+					    log_sockaddr(
+					    (struct sockaddr *)&la->sa));
+					TAILQ_REMOVE(conf->listen_addrs, la,
+					    entry);
+					close(la->fd);
+					free(la);
+				}
+			}
+
+			/* add new listeners */
+			while ((la = TAILQ_FIRST(nconf->listen_addrs)) !=
+			    NULL) {
+				TAILQ_REMOVE(nconf->listen_addrs, la, entry);
+				TAILQ_INSERT_TAIL(conf->listen_addrs, la,
+				    entry);
+			}
+
+			setup_listeners();
+			free(nconf->listen_addrs);
 			free(nconf);
 			nconf = NULL;
 			pending_reconf = 0;
@@ -2068,6 +2169,41 @@ session_dispatch_imsg(struct imsgbuf *ibuf, int idx)
 	}
 }
 
+int
+la_cmp(struct listen_addr *a, struct listen_addr *b)
+{
+	struct sockaddr_in	*in_a, *in_b;
+	struct sockaddr_in6	*in6_a, *in6_b;
+
+	if (a->sa.ss_family != b->sa.ss_family)
+		return (1);
+
+	switch (a->sa.ss_family) {
+	case AF_INET:
+		in_a = (struct sockaddr_in *)&a->sa;
+		in_b = (struct sockaddr_in *)&b->sa;
+		if (in_a->sin_addr.s_addr != in_b->sin_addr.s_addr)
+			return (1);
+		if (in_a->sin_port != in_b->sin_port)
+			return (1);
+		break;
+	case AF_INET6:
+		in6_a = (struct sockaddr_in6 *)&a->sa;
+		in6_b = (struct sockaddr_in6 *)&b->sa;
+		if (bcmp(&in6_a->sin6_addr, &in6_b->sin6_addr,
+		    sizeof(struct in6_addr)))
+			return (1);
+		if (in6_a->sin6_port != in6_b->sin6_port)
+			return (1);
+		break;
+	default:
+		fatal("king bula sez: unknown address family");
+		/* not reached */
+	}
+
+	return (0);
+}
+
 struct peer *
 getpeerbyaddr(struct bgpd_addr *addr)
 {
diff --git a/usr.sbin/bgpd/session.h b/usr.sbin/bgpd/session.h
index 23232ab3731..ce140a7a23a 100644
--- a/usr.sbin/bgpd/session.h
+++ b/usr.sbin/bgpd/session.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: session.h,v 1.53 2004/05/28 18:39:09 henning Exp $ */
+/*	$OpenBSD: session.h,v 1.54 2004/06/06 17:38:10 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -207,7 +207,7 @@ int	 parse_config(char *, struct bgpd_config *, struct mrt_head *,
 
 /* config.c */
 int	 merge_config(struct bgpd_config *, struct bgpd_config *,
-	    struct peer *);
+	    struct peer *, struct listen_addrs *);
 
 /* rde.c */
 int	 rde_main(struct bgpd_config *, struct network_head *,