Not only reset the connection when a fatal error is received (or sent)

but also reset the cache and start totally fresh. The RFC is exceptionally
vague about error handling but in most cases the cache state is enough
off after an error that a fresh restart makes most sense.
With and OK job@

1 files changed, 28 insertions, 16 deletions

diff --git a/usr.sbin/bgpd/rtr_proto.c b/usr.sbin/bgpd/rtr_proto.c
index 5ffe3a7dc03..1187cdb6ba6 100644
--- a/usr.sbin/bgpd/rtr_proto.c
+++ b/usr.sbin/bgpd/rtr_proto.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtr_proto.c,v 1.9 2023/01/31 14:38:43 job Exp $ */
+/*	$OpenBSD: rtr_proto.c,v 1.10 2023/01/31 17:14:27 claudio Exp $ */
 
 /*
  * Copyright (c) 2020 Claudio Jeker <claudio@openbsd.org>
@@ -83,7 +83,7 @@ struct rtr_endofdata {
 enum rtr_event {
 	RTR_EVNT_START,
 	RTR_EVNT_CON_OPEN,
-	RTR_EVNT_CON_CLOSED,
+	RTR_EVNT_CON_CLOSE,
 	RTR_EVNT_TIMER_REFRESH,
 	RTR_EVNT_TIMER_RETRY,
 	RTR_EVNT_TIMER_EXPIRE,
@@ -93,6 +93,7 @@ enum rtr_event {
 	RTR_EVNT_END_OF_DATA,
 	RTR_EVNT_CACHE_RESET,
 	RTR_EVNT_NO_DATA,
+	RTR_EVNT_RESET_AND_CLOSE,
 };
 
 static const char *rtr_eventnames[] = {
@@ -107,7 +108,8 @@ static const char *rtr_eventnames[] = {
 	"cache response received",
 	"end of data received",
 	"cache reset received",
-	"no data"
+	"no data",
+	"connection closed with reset",
 };
 
 enum rtr_state {
@@ -645,7 +647,7 @@ rtr_parse_error(struct rtr_session *rs, uint8_t *buf, size_t len)
 	if (len < pdu_len + sizeof(pdu_len)) {
 		log_warnx("rtr %s: received %s: bad encapsulated pdu len: %u "
 		    "byte", log_rtr(rs), log_rtr_type(ERROR_REPORT), pdu_len);
-		rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+		rtr_fsm(rs, RTR_EVNT_RESET_AND_CLOSE);
 		return -1;
 	}
 
@@ -659,7 +661,7 @@ rtr_parse_error(struct rtr_session *rs, uint8_t *buf, size_t len)
 	if (len < msg_len + sizeof(msg_len)) {
 		log_warnx("rtr %s: received %s: bad msg len: %u byte",
 		    log_rtr(rs), log_rtr_type(ERROR_REPORT), msg_len);
-		rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+		rtr_fsm(rs, RTR_EVNT_RESET_AND_CLOSE);
 		return -1;
 	}
 
@@ -674,7 +676,7 @@ rtr_parse_error(struct rtr_session *rs, uint8_t *buf, size_t len)
 	if (errcode == NO_DATA_AVAILABLE) {
 		rtr_fsm(rs, RTR_EVNT_NO_DATA);
 	} else {
-		rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+		rtr_fsm(rs, RTR_EVNT_RESET_AND_CLOSE);
 		rs->last_recv_error = errcode;
 		if (str)
 			strlcpy(rs->last_recv_msg, str,
@@ -788,7 +790,16 @@ rtr_fsm(struct rtr_session *rs, enum rtr_event event)
 	enum rtr_state prev_state = rs->state;
 
 	switch (event) {
-	case RTR_EVNT_CON_CLOSED:
+	case RTR_EVNT_RESET_AND_CLOSE:
+		rs->state = RTR_STATE_ERROR;
+		/* FALLTHROUGH */
+	case RTR_EVNT_CON_CLOSE:
+		if (rs->state == RTR_STATE_ERROR) {
+			/* reset session */
+			rs->session_id = -1;
+			free_roatree(&rs->roa_set);
+			rtr_recalc();
+		}
 		if (rs->state != RTR_STATE_CLOSED) {
 			/* flush buffers */
 			msgbuf_clear(&rs->w);
@@ -805,7 +816,7 @@ rtr_fsm(struct rtr_session *rs, enum rtr_event event)
 	case RTR_EVNT_TIMER_RETRY:
 		switch (rs->state) {
 		case RTR_STATE_ERROR:
-			rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+			rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 			return;
 		case RTR_STATE_CLOSED:
 			timer_set(&rs->timers, Timer_Rtr_Retry, rs->retry);
@@ -851,6 +862,7 @@ rtr_fsm(struct rtr_session *rs, enum rtr_event event)
 		/* reset session and retry after a quick wait */
 		rs->session_id = -1;
 		free_roatree(&rs->roa_set);
+		rtr_recalc();
 		timer_set(&rs->timers, Timer_Rtr_Retry,
 		    arc4random_uniform(10));
 		break;
@@ -883,12 +895,12 @@ rtr_dispatch_msg(struct pollfd *pfd, struct rtr_session *rs)
 
 	if (pfd->revents & POLLHUP) {
 		log_warnx("rtr %s: Connection closed, hangup", log_rtr(rs));
-		rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+		rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 		return;
 	}
 	if (pfd->revents & (POLLERR|POLLNVAL)) {
 		log_warnx("rtr %s: Connection closed, error", log_rtr(rs));
-		rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+		rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 		return;
 	}
 	if (pfd->revents & POLLOUT && rs->w.queued) {
@@ -898,24 +910,24 @@ rtr_dispatch_msg(struct pollfd *pfd, struct rtr_session *rs)
 				    log_rtr(rs));
 			else if (error == -1)
 				log_warn("rtr %s: write error", log_rtr(rs));
-			rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+			rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 			return;
 		}
 		if (rs->w.queued == 0 && rs->state == RTR_STATE_ERROR)
-			rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+			rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 	}
 	if (pfd->revents & POLLIN) {
 		if ((n = read(rs->fd, rs->r.buf + rs->r.wpos,
 		    sizeof(rs->r.buf) - rs->r.wpos)) == -1) {
 			if (errno != EINTR && errno != EAGAIN) {
 				log_warn("rtr %s: read error", log_rtr(rs));
-				rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+				rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 			}
 			return;
 		}
 		if (n == 0) {
 			log_warnx("rtr %s: Connection closed", log_rtr(rs));
-			rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+			rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 			return;
 		}
 		rs->r.wpos += n;
@@ -1066,7 +1078,7 @@ rtr_free(struct rtr_session *rs)
 	if (rs == NULL)
 		return;
 
-	rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+	rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 	timer_remove_all(&rs->timers);
 	free_roatree(&rs->roa_set);
 	free(rs);
@@ -1077,7 +1089,7 @@ rtr_open(struct rtr_session *rs, int fd)
 {
 	if (rs->state != RTR_STATE_CLOSED) {
 		log_warnx("rtr %s: bad session state", log_rtr(rs));
-		rtr_fsm(rs, RTR_EVNT_CON_CLOSED);
+		rtr_fsm(rs, RTR_EVNT_CON_CLOSE);
 	}
 
 	log_debug("rtr %s: connection opened", log_rtr(rs));