ospfd: Fix several problems with direct acknowledgments and improved delay acks.

   1. On P2MP interfaces, direct ack would include the same LSA multiple times
      multiple packets are processed before the OSPF interfae direct LSA
      acknowledgment event is processed. Now duplicates LSA in the same event
      are suppressed.
   2. On non-broadcast interfaces, direct acks for multiple neighbors would be
      unicast to the same neighbor due to the multiple OSPF LS Update packets
      being process prior to the OSPF interface direct ack event. Now, separate
      direct acks are unicast to the neighbors requiring them.
   3. The interface delayed acknowledgment timer runs would run continously
      (every second as long as the interace is up). Now, the timer is set
      when delayed acknowledgments are queued and all queued delayed
      acknowledges are sent when it fires.
   4. For non-broadcast interface delayed acknowledgments, the logic to send
      to multiple neighbors wasn't working because the list was emptied while
      building the packet for the first neighbor.

Signed-off-by: Acee Lindem <acee@lindem.com>

1 files changed, 30 insertions, 14 deletions

diff --git a/ospfd/ospf_interface.c b/ospfd/ospf_interface.c
index 803c36861..c4210eb70 100644
--- a/ospfd/ospf_interface.c
+++ b/ospfd/ospf_interface.c
@@ -186,10 +186,12 @@ static void ospf_if_default_variables(struct ospf_interface *oi)
 
 	oi->crypt_seqnum = 0;
 
-	/* This must be short, (less than RxmtInterval)
-	   - RFC 2328 Section 13.5 para 3.  Set to 1 second to avoid Acks being
-	     held back for too long - MAG */
-	oi->v_ls_ack = 1;
+	/*
+	 * The OSPF LS ACK Delay timer must be less than the LS Retransmision
+	 * timer. As per RFC 2328 Section 13.5 paragraph 3,  Set to 1 second
+	 * to avoid Acks being held back for too long
+	 */
+	oi->v_ls_ack_delayed = OSPF_ACK_DELAY_DEFAULT;
 }
 
 /* lookup oi for specified prefix/ifp */
@@ -272,9 +274,9 @@ struct ospf_interface *ospf_if_new(struct ospf *ospf, struct interface *ifp,
 	/* Initialize static neighbor list. */
 	oi->nbr_nbma = list_new();
 
-	/* Initialize Link State Acknowledgment list. */
-	oi->ls_ack = list_new();
-	oi->ls_ack_direct.ls_ack = list_new();
+	/* Initialize Link State Acknowledgment lists. */
+	ospf_lsa_list_init(&oi->ls_ack_delayed);
+	ospf_lsa_list_init(&oi->ls_ack_direct);
 
 	/* Set default values. */
 	ospf_if_default_variables(oi);
@@ -306,6 +308,22 @@ struct ospf_interface *ospf_if_new(struct ospf *ospf, struct interface *ifp,
 	return oi;
 }
 
+/*
+ * Cleanup Interface Ack List
+ */
+static void ospf_if_cleanup_ack_list(struct ospf_lsa_list_head *ls_ack_list)
+{
+	struct ospf_lsa_list_entry *ls_ack_list_entry;
+	struct ospf_lsa *lsa;
+
+	frr_each_safe (ospf_lsa_list, ls_ack_list, ls_ack_list_entry) {
+		lsa = ls_ack_list_entry->lsa;
+		ospf_lsa_list_del(ls_ack_list, ls_ack_list_entry);
+		XFREE(MTYPE_OSPF_LSA_LIST, ls_ack_list_entry);
+		ospf_lsa_unlock(&lsa);
+	}
+}
+
 /* Restore an interface to its pre UP state
    Used from ism_interface_down only */
 void ospf_if_cleanup(struct ospf_interface *oi)
@@ -314,7 +332,6 @@ void ospf_if_cleanup(struct ospf_interface *oi)
 	struct listnode *node, *nnode;
 	struct ospf_neighbor *nbr;
 	struct ospf_nbr_nbma *nbr_nbma;
-	struct ospf_lsa *lsa;
 
 	/* oi->nbrs and oi->nbr_nbma should be deleted on InterfaceDown event */
 	/* delete all static neighbors attached to this interface */
@@ -338,10 +355,9 @@ void ospf_if_cleanup(struct ospf_interface *oi)
 				OSPF_NSM_EVENT_EXECUTE(nbr, NSM_KillNbr);
 	}
 
-	/* Cleanup Link State Acknowlegdment list. */
-	for (ALL_LIST_ELEMENTS(oi->ls_ack, node, nnode, lsa))
-		ospf_lsa_unlock(&lsa); /* oi->ls_ack */
-	list_delete_all_node(oi->ls_ack);
+	/* Cleanup Link State Delayed Acknowlegdment list. */
+	ospf_if_cleanup_ack_list(&oi->ls_ack_delayed);
+	ospf_if_cleanup_ack_list(&oi->ls_ack_direct);
 
 	oi->crypt_seqnum = 0;
 
@@ -377,8 +393,8 @@ void ospf_if_free(struct ospf_interface *oi)
 	/* Free any lists that should be freed */
 	list_delete(&oi->nbr_nbma);
 
-	list_delete(&oi->ls_ack);
-	list_delete(&oi->ls_ack_direct.ls_ack);
+	ospf_if_cleanup_ack_list(&oi->ls_ack_delayed);
+	ospf_if_cleanup_ack_list(&oi->ls_ack_direct);
 
 	if (IS_DEBUG_OSPF_EVENT)
 		zlog_debug("%s: ospf interface %s vrf %s id %u deleted",