Add support for draft-ietf-idr-shutdown

    BGP state = Idle, marked down with shutdown reason "goodbye, we are
    upgrading to openbsd 6.1", down for 00:00:17

developed by Peter van Dijk <peter.van.dijk@powerdns.com> and Job
Snijders <job@ntt.net>, thank you!

OK benno@

12 files changed, 170 insertions, 31 deletions

diff --git a/usr.sbin/bgpctl/bgpctl.8 b/usr.sbin/bgpctl/bgpctl.8
index 6c2bae6ab90..239f6d0ca09 100644
--- a/usr.sbin/bgpctl/bgpctl.8
+++ b/usr.sbin/bgpctl/bgpctl.8
@@ -1,4 +1,4 @@
-.\" $OpenBSD: bgpctl.8,v 1.71 2016/10/26 17:24:13 jmc Exp $
+.\" $OpenBSD: bgpctl.8,v 1.72 2017/01/13 18:59:12 phessler Exp $
 .\"
 .\" Copyright (c) 2003 Henning Brauer <henning@openbsd.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: October 26 2016 $
+.Dd $Mdocdate: January 13 2017 $
 .Dt BGPCTL 8
 .Os
 .Sh NAME
@@ -104,8 +104,16 @@ Destroy a previously cloned peer.
 The peer must be down before calling this function.
 .Ar peer
 may be the neighbor's address or description.
-.It Cm neighbor Ar peer Cm down
+.It Cm neighbor Ar peer Cm down Op Ar reason
 Take the BGP session to the specified neighbor down.
+If a
+.Ar reason
+is provided, the
+.Ar reason
+is sent as Administrative Shutdown Communication to the neighbor.
+The
+.Ar reason
+cannot exceed 128 octets.
 .Ar peer
 may be the neighbor's address or description.
 .It Cm neighbor Ar peer Cm refresh
diff --git a/usr.sbin/bgpctl/bgpctl.c b/usr.sbin/bgpctl/bgpctl.c
index 91e2cbc70d2..eb14bfe73ef 100644
--- a/usr.sbin/bgpctl/bgpctl.c
+++ b/usr.sbin/bgpctl/bgpctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpctl.c,v 1.190 2016/10/14 16:05:35 phessler Exp $ */
+/*	$OpenBSD: bgpctl.c,v 1.191 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2003 Henning Brauer <henning@openbsd.org>
@@ -162,6 +162,7 @@ main(int argc, char *argv[])
 
 	memcpy(&neighbor.addr, &res->peeraddr, sizeof(neighbor.addr));
 	strlcpy(neighbor.descr, res->peerdesc, sizeof(neighbor.descr));
+	strlcpy(neighbor.shutcomm, res->shutcomm, sizeof(neighbor.shutcomm));
 
 	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
 		err(1, "control_init: socket");
@@ -722,6 +723,13 @@ show_neighbor_msg(struct imsg *imsg, enum neighbor_views nv)
 		    inet_ntoa(ina));
 		printf("%s\n", print_auth_method(p->auth.method));
 		printf("  BGP state = %s", statenames[p->state]);
+		if (p->conf.down) {
+			printf(", marked down");
+			if (*(p->conf.shutcomm)) {
+				printf(" with shutdown reason \"%s\"",
+				    log_shutcomm(p->conf.shutcomm));
+			}
+		}
 		if (p->stats.last_updown != 0)
 			printf(", %s for %s",
 			    p->state == STATE_ESTABLISHED ? "up" : "down",
@@ -756,6 +764,10 @@ show_neighbor_msg(struct imsg *imsg, enum neighbor_views nv)
 			break;
 		print_neighbor_msgstats(p);
 		printf("\n");
+		if (*(p->stats.last_shutcomm)) {
+			printf("  Last received shutdown reason: \"%s\"\n",
+			    log_shutcomm(p->stats.last_shutcomm));
+		}
 		if (p->state == STATE_IDLE) {
 			static const char	*errstr;
 
diff --git a/usr.sbin/bgpctl/parser.c b/usr.sbin/bgpctl/parser.c
index 4b65785a0a6..f93881d2cee 100644
--- a/usr.sbin/bgpctl/parser.c
+++ b/usr.sbin/bgpctl/parser.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parser.c,v 1.74 2016/10/14 16:05:35 phessler Exp $ */
+/*	$OpenBSD: parser.c,v 1.75 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -45,6 +45,7 @@ enum token_type {
 	PREFIX,
 	PEERDESC,
 	RIBNAME,
+	SHUTDOWN_COMMUNICATION,
 	COMMUNITY,
 	LARGE_COMMUNITY,
 	LOCALPREF,
@@ -245,9 +246,15 @@ static const struct token t_neighbor[] = {
 	{ ENDTOKEN,	"",		NONE,		NULL}
 };
 
+static const struct token t_nei_mod_shutc[] = {
+	{ NOTOKEN,	"",		NONE,		NULL},
+	{ SHUTDOWN_COMMUNICATION, "",	NONE,		NULL},
+	{ ENDTOKEN,	"",		NONE,		NULL}
+};
+
 static const struct token t_neighbor_modifiers[] = {
 	{ KEYWORD,	"up",		NEIGHBOR_UP,		NULL},
-	{ KEYWORD,	"down",		NEIGHBOR_DOWN,		NULL},
+	{ KEYWORD,	"down",		NEIGHBOR_DOWN,		t_nei_mod_shutc},
 	{ KEYWORD,	"clear",	NEIGHBOR_CLEAR,		NULL},
 	{ KEYWORD,	"refresh",	NEIGHBOR_RREFRESH,	NULL},
 	{ KEYWORD,	"destroy",	NEIGHBOR_DESTROY,	NULL},
@@ -571,6 +578,16 @@ match_token(int *argc, char **argv[], const struct token table[])
 				t = &table[i];
 			}
 			break;
+		case SHUTDOWN_COMMUNICATION:
+			if (!match && word != NULL && wordlen > 0) {
+				if (strlcpy(res.shutcomm, word,
+				    sizeof(res.shutcomm)) >=
+				    sizeof(res.shutcomm))
+					errx(1, "shutdown reason too long");
+				match++;
+				t = &table[i];
+			}
+			break;
 		case COMMUNITY:
 			if (word != NULL && wordlen > 0 &&
 			    parse_community(word, &res)) {
@@ -694,6 +711,9 @@ show_valid_args(const struct token table[])
 		case RIBNAME:
 			fprintf(stderr, "  <rib name>\n");
 			break;
+		case SHUTDOWN_COMMUNICATION:
+			fprintf(stderr, "  <shutdown reason>\n");
+			break;
 		case COMMUNITY:
 			fprintf(stderr, "  <community>\n");
 			break;
diff --git a/usr.sbin/bgpctl/parser.h b/usr.sbin/bgpctl/parser.h
index cc66a04a4fc..33dfb94c1b0 100644
--- a/usr.sbin/bgpctl/parser.h
+++ b/usr.sbin/bgpctl/parser.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parser.h,v 1.28 2016/10/14 16:05:35 phessler Exp $ */
+/*	$OpenBSD: parser.h,v 1.29 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -66,6 +66,7 @@ struct parse_result {
 	struct filter_largecommunity  large_community;
 	char			 peerdesc[PEER_DESCR_LEN];
 	char			 rib[PEER_DESCR_LEN];
+	char			 shutcomm[SHUT_COMM_LEN];
 	char			*irr_outdir;
 	int			 flags;
 	u_int			 rtableid;
diff --git a/usr.sbin/bgpd/bgpd.8 b/usr.sbin/bgpd/bgpd.8
index 9d78dab8293..a6668f5a312 100644
--- a/usr.sbin/bgpd/bgpd.8
+++ b/usr.sbin/bgpd/bgpd.8
@@ -1,4 +1,4 @@
-.\" $OpenBSD: bgpd.8,v 1.50 2016/11/10 10:01:33 phessler Exp $
+.\" $OpenBSD: bgpd.8,v 1.51 2017/01/13 18:59:12 phessler Exp $
 .\"
 .\" Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: November 10 2016 $
+.Dd $Mdocdate: January 13 2017 $
 .Dt BGPD 8
 .Os
 .Sh NAME
@@ -238,17 +238,6 @@ control socket
 .Re
 .Pp
 .Rs
-.%A J. Snijders
-.%A J. Heitz
-.%A K. Patel
-.%A I. Bagdonas
-.%A A. Simpson
-.%D September 2016
-.%R draft-ietf-idr-large-community
-.%T Large BGP Communities Attribute
-.Re
-.Pp
-.Rs
 .%A A. Heffernan
 .%D August 1998
 .%R RFC 2385
@@ -381,6 +370,26 @@ control socket
 .%R RFC 6608
 .%T Subcodes for BGP Finite State Machine Error
 .Re
+.Pp
+.Rs
+.%A J. Snijders
+.%A J. Heitz
+.%A K. Patel
+.%A I. Bagdonas
+.%A N. Hilliard
+.%D January 2017
+.%R draft-ietf-idr-large-community
+.%T BGP Large Communities Attribute
+.Re
+.Pp
+.Rs
+.%A J. Snijders
+.%A J. Heitz
+.%A J. Scudder
+.%D January 2017
+.%R draft-ietf-idr-shutdown
+.%T BGP Administrative Shutdown Communication
+.Re
 .Sh HISTORY
 The
 .Nm
diff --git a/usr.sbin/bgpd/bgpd.conf.5 b/usr.sbin/bgpd/bgpd.conf.5
index e982eeeb083..312cf85b5c7 100644
--- a/usr.sbin/bgpd/bgpd.conf.5
+++ b/usr.sbin/bgpd/bgpd.conf.5
@@ -1,4 +1,4 @@
-.\" $OpenBSD: bgpd.conf.5,v 1.151 2016/10/30 16:50:22 phessler Exp $
+.\" $OpenBSD: bgpd.conf.5,v 1.152 2017/01/13 18:59:12 phessler Exp $
 .\"
 .\" Copyright (c) 2004 Claudio Jeker <claudio@openbsd.org>
 .\" Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -16,7 +16,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: October 30 2016 $
+.Dd $Mdocdate: January 13 2017 $
 .Dt BGPD.CONF 5
 .Os
 .Sh NAME
@@ -737,9 +737,18 @@ The description is used when logging neighbor events, in status
 reports, for specifying neighbors, etc., but has no further meaning to
 .Xr bgpd 8 .
 .Pp
-.It Ic down
+.It Ic down Op Ar reason
 Do not start the session when bgpd comes up but stay in
 .Em IDLE .
+If the session is cleared at runtime, after a
+.Ic down
+.Ar reason
+was configured at runtime, the
+.Ar reason
+is sent as Administrative Shutdown Communication.
+The
+.Ar reason
+cannot exceed 128 octets.
 .Pp
 .It Xo
 .Ic dump
diff --git a/usr.sbin/bgpd/bgpd.h b/usr.sbin/bgpd/bgpd.h
index 87dd2d891b2..b105f3f48c9 100644
--- a/usr.sbin/bgpd/bgpd.h
+++ b/usr.sbin/bgpd/bgpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpd.h,v 1.297 2016/10/14 16:05:35 phessler Exp $ */
+/*	$OpenBSD: bgpd.h,v 1.298 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -40,6 +40,7 @@
 #define	CONFFILE			"/etc/bgpd.conf"
 #define	BGPD_USER			"_bgpd"
 #define	PEER_DESCR_LEN			32
+#define	SHUT_COMM_LEN			129
 #define	PFTABLE_LEN			32
 #define	TCP_MD5_KEY_LEN			80
 #define	IPSEC_ENC_KEY_LEN		32
@@ -299,6 +300,7 @@ struct peer_config {
 	struct capabilities	 capabilities;
 	char			 group[PEER_DESCR_LEN];
 	char			 descr[PEER_DESCR_LEN];
+	char			 shutcomm[SHUT_COMM_LEN];
 	char			 rib[PEER_DESCR_LEN];
 	char			 if_depend[IFNAMSIZ];
 	char			 demote_group[IFNAMSIZ];
@@ -586,6 +588,7 @@ struct ctl_show_nexthop {
 struct ctl_neighbor {
 	struct bgpd_addr	addr;
 	char			descr[PEER_DESCR_LEN];
+	char			shutcomm[SHUT_COMM_LEN];
 	int			show_timers;
 };
 
@@ -1084,6 +1087,7 @@ const char	*log_sockaddr(struct sockaddr *);
 const char	*log_as(u_int32_t);
 const char	*log_rd(u_int64_t);
 const char	*log_ext_subtype(u_int8_t);
+const char	*log_shutcomm(const char *);
 int		 aspath_snprint(char *, size_t, void *, u_int16_t);
 int		 aspath_asprint(char **, void *, u_int16_t);
 size_t		 aspath_strlen(void *, u_int16_t);
diff --git a/usr.sbin/bgpd/control.c b/usr.sbin/bgpd/control.c
index 903892ca606..63f41ae8072 100644
--- a/usr.sbin/bgpd/control.c
+++ b/usr.sbin/bgpd/control.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: control.c,v 1.84 2017/01/08 23:04:42 krw Exp $ */
+/*	$OpenBSD: control.c,v 1.85 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -340,9 +340,15 @@ control_dispatch_msg(struct pollfd *pfd, u_int *ctl_cnt)
 				switch (imsg.hdr.type) {
 				case IMSG_CTL_NEIGHBOR_UP:
 					bgp_fsm(p, EVNT_START);
+					p->conf.down = 0;
+					p->conf.shutcomm[0] = '\0';
 					control_result(c, CTL_RES_OK);
 					break;
 				case IMSG_CTL_NEIGHBOR_DOWN:
+					p->conf.down = 1;
+					strlcpy(p->conf.shutcomm,
+					    neighbor->shutcomm,
+					    sizeof(neighbor->shutcomm));
 					session_stop(p, ERR_CEASE_ADMIN_DOWN);
 					control_result(c, CTL_RES_OK);
 					break;
diff --git a/usr.sbin/bgpd/parse.y b/usr.sbin/bgpd/parse.y
index 06d614b9f57..16b0fc87a4c 100644
--- a/usr.sbin/bgpd/parse.y
+++ b/usr.sbin/bgpd/parse.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.y,v 1.293 2017/01/05 13:53:09 krw Exp $ */
+/*	$OpenBSD: parse.y,v 1.294 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -1052,9 +1052,20 @@ peeropts	: REMOTEAS as4number	{
 		| PASSIVE		{
 			curpeer->conf.passive = 1;
 		}
-		| DOWN		{
+		| DOWN			{
 			curpeer->conf.down = 1;
 		}
+		| DOWN STRING		{
+			curpeer->conf.down = 1;
+			if (strlcpy(curpeer->conf.shutcomm, $2,
+				sizeof(curpeer->conf.shutcomm)) >=
+				sizeof(curpeer->conf.shutcomm)) {
+				    yyerror("shutdown reason too long");
+				    free($2);
+				    YYERROR;
+			}
+			free($2);
+		}
 		| RIB STRING	{
 			if (!find_rib($2)) {
 				yyerror("rib \"%s\" does not exist.", $2);
diff --git a/usr.sbin/bgpd/session.c b/usr.sbin/bgpd/session.c
index 02f6a15012e..b710d27c135 100644
--- a/usr.sbin/bgpd/session.c
+++ b/usr.sbin/bgpd/session.c
@@ -1,7 +1,8 @@
-/*	$OpenBSD: session.c,v 1.356 2016/12/19 07:19:55 claudio Exp $ */
+/*	$OpenBSD: session.c,v 1.357 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2003, 2004, 2005 Henning Brauer <henning@openbsd.org>
+ * Copyright (c) 2017 Peter van Dijk <peter.van.dijk@powerdns.com>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -571,6 +572,9 @@ session_main(int debug, int verbose)
 
 	while ((p = peers) != NULL) {
 		peers = p->next;
+		strlcpy(p->conf.shutcomm,
+		    "bgpd shutting down",
+		    sizeof(p->conf.shutcomm));
 		session_stop(p, ERR_CEASE_ADMIN_DOWN);
 		pfkey_remove(p);
 		free(p);
@@ -2221,6 +2225,7 @@ parse_notification(struct peer *peer)
 	u_int8_t	 subcode;
 	u_int8_t	 capa_code;
 	u_int8_t	 capa_len;
+	u_int8_t	 shutcomm_len;
 	u_int8_t	 i;
 
 	/* just log */
@@ -2315,6 +2320,31 @@ parse_notification(struct peer *peer)
 		return (1);
 	}
 
+	if (errcode == ERR_CEASE && subcode == ERR_CEASE_ADMIN_DOWN) {
+		if (datalen >= sizeof(shutcomm_len)) {
+			memcpy(&shutcomm_len, p, sizeof(shutcomm_len));
+			p += sizeof(shutcomm_len);
+			datalen -= sizeof(shutcomm_len);
+			if(datalen < shutcomm_len) {
+			    log_peer_warnx(&peer->conf,
+				"received truncated shutdown reason");
+			    return (0);
+			}
+			if (shutcomm_len > (SHUT_COMM_LEN-1)) {
+			    log_peer_warnx(&peer->conf,
+				"received overly long shutdown reason");
+			    return (0);
+			}
+			memcpy(peer->stats.last_shutcomm, p, shutcomm_len);
+			peer->stats.last_shutcomm[shutcomm_len] = '\0';
+			log_peer_warnx(&peer->conf,
+			    "received shutdown reason: \"%s\"",
+			    log_shutcomm(peer->stats.last_shutcomm));
+			p += shutcomm_len;
+			datalen -= shutcomm_len;
+		}
+	}
+
 	return (0);
 }
 
@@ -3195,11 +3225,29 @@ session_demote(struct peer *p, int level)
 void
 session_stop(struct peer *peer, u_int8_t subcode)
 {
+	char data[SHUT_COMM_LEN];
+	uint8_t datalen;
+	uint8_t shutcomm_len;
+	char *communication;
+
+	datalen = 0;
+
+	communication = peer->conf.shutcomm;
+
+	if (subcode == ERR_CEASE_ADMIN_DOWN && communication &&
+	    *communication) {
+		shutcomm_len = strlen(communication);
+		if(shutcomm_len < SHUT_COMM_LEN) {
+			data[0] = shutcomm_len;
+			datalen = shutcomm_len + sizeof(data[0]);
+			memcpy(data + 1, communication, shutcomm_len);
+		}
+	}
 	switch (peer->state) {
 	case STATE_OPENSENT:
 	case STATE_OPENCONFIRM:
 	case STATE_ESTABLISHED:
-		session_notification(peer, ERR_CEASE, subcode, NULL, 0);
+		session_notification(peer, ERR_CEASE, subcode, data, datalen);
 		break;
 	default:
 		/* session not open, no need to send notification */
diff --git a/usr.sbin/bgpd/session.h b/usr.sbin/bgpd/session.h
index bd11ac4efe4..863d0535178 100644
--- a/usr.sbin/bgpd/session.h
+++ b/usr.sbin/bgpd/session.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: session.h,v 1.121 2015/10/25 18:49:01 claudio Exp $ */
+/*	$OpenBSD: session.h,v 1.122 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -168,6 +168,7 @@ struct peer_stats {
 	u_int32_t		 prefix_cnt;
 	u_int8_t		 last_sent_errcode;
 	u_int8_t		 last_sent_suberr;
+	char			 last_shutcomm[SHUT_COMM_LEN];
 };
 
 enum Timer {
diff --git a/usr.sbin/bgpd/util.c b/usr.sbin/bgpd/util.c
index 39ad7f1b538..a660f38a393 100644
--- a/usr.sbin/bgpd/util.c
+++ b/usr.sbin/bgpd/util.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: util.c,v 1.21 2016/06/03 17:36:37 benno Exp $ */
+/*	$OpenBSD: util.c,v 1.22 2017/01/13 18:59:12 phessler Exp $ */
 
 /*
  * Copyright (c) 2006 Claudio Jeker <claudio@openbsd.org>
@@ -24,6 +24,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <vis.h>
 
 #include "bgpd.h"
 #include "rde.h"
@@ -159,6 +160,15 @@ log_ext_subtype(u_int8_t subtype)
 }
 
 const char *
+log_shutcomm(const char *communication) {
+	static char buf[(SHUT_COMM_LEN - 1) * 4 + 1];
+
+	strnvis(buf, communication, sizeof(buf), VIS_NL | VIS_OCTAL);
+
+	return buf;
+}
+
+const char *
 aspath_delim(u_int8_t seg_type, int closing)
 {
 	static char db[8];