Several fixes in the Conditionally Received (CR) mode.

* If we fail to accept a packet when in the CR mode, do not ack it;
* Add missing ntohl() when storing the next multicast sequence tlv;
* The CR flag in the neighbor should be cleared out after use.

1 files changed, 17 insertions, 16 deletions

diff --git a/usr.sbin/eigrpd/packet.c b/usr.sbin/eigrpd/packet.c
index 78acc8f2e7c..58c7220f68e 100644
--- a/usr.sbin/eigrpd/packet.c
+++ b/usr.sbin/eigrpd/packet.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: packet.c,v 1.7 2016/01/15 12:29:29 renato Exp $ */
+/*	$OpenBSD: packet.c,v 1.8 2016/01/15 12:43:02 renato Exp $ */
 
 /*
  * Copyright (c) 2015 Renato Westphal <renato@openbsd.org>
@@ -248,20 +248,6 @@ recv_packet_nbr(struct nbr *nbr, struct eigrp_hdr *eigrp_hdr,
 	 */
 	nbr_start_timeout(nbr);
 
-	/* ack processing */
-	if (ack != 0)
-		rtp_process_ack(nbr, ack);
-	if (seq != 0) {
-		/* check for sequence wraparound */
-		if (nbr->recv_seq >= seq &&
-		   !(nbr->recv_seq == UINT32_MAX && seq == 1)) {
-			log_debug("%s: duplicate packet", __func__);
-			rtp_send_ack(nbr);
-			return (-1);
-		}
-		nbr->recv_seq = seq;
-	}
-
 	/* handle the sequence tlv */
 	if (eigrp_hdr->opcode == EIGRP_OPC_HELLO &&
 	    !TAILQ_EMPTY(seq_addr_list)) {
@@ -288,16 +274,31 @@ recv_packet_nbr(struct nbr *nbr, struct eigrp_hdr *eigrp_hdr,
 			}
 		}
 		if (tm)
-			nbr->next_mcast_seq = tm->seq;
+			nbr->next_mcast_seq = ntohl(tm->seq);
 	}
 
 	if ((ntohl(eigrp_hdr->flags) & EIGRP_HDR_FLAG_CR)) {
 		if (!(nbr->flags & F_EIGRP_NBR_CR_MODE))
 			return (-1);
+		nbr->flags &= ~F_EIGRP_NBR_CR_MODE;
 		if (ntohl(eigrp_hdr->seq_num) != nbr->next_mcast_seq)
 			return (-1);
 	}
 
+	/* ack processing */
+	if (ack != 0)
+		rtp_process_ack(nbr, ack);
+	if (seq != 0) {
+		/* check for sequence wraparound */
+		if (nbr->recv_seq >= seq &&
+		   !(nbr->recv_seq == UINT32_MAX && seq == 1)) {
+			log_debug("%s: duplicate packet", __func__);
+			rtp_send_ack(nbr);
+			return (-1);
+		}
+		nbr->recv_seq = seq;
+	}
+
 	return (0);
 }