OSPF: Reject duplicate DBDES packets after dead interval

Master may free last DBDES packet immediately. Slave must wait dead
interval before freeing last DBDES packet and then reject duplicate
DBDES packets with SeqNumberMismatch.

diff --git a/proto/ospf/dbdes.c b/proto/ospf/dbdes.c
index 4d3bbe8c257451a58e30913f197aa8457931edbf..a1559782a2bb00629d3d771200919502dcf588b1 100644 (file)
--- a/proto/ospf/dbdes.c
+++ b/proto/ospf/dbdes.c
@@ -238,6 +238,14 @@ ospf_rxmt_dbdes(struct ospf_proto *p, struct ospf_neighbor *n)
   ospf_do_send_dbdes(p, n);
 }
 
+void
+ospf_reset_ldd(struct ospf_proto *p UNUSED, struct ospf_neighbor *n)
+{
+  mb_free(n->ldd_buffer);
+  n->ldd_buffer = NULL;
+  n->ldd_bsize = 0;
+}
+
 static int
 ospf_process_dbdes(struct ospf_proto *p, struct ospf_packet *pkt, struct ospf_neighbor *n)
 {
@@ -434,6 +442,7 @@ ospf_receive_dbdes(struct ospf_packet *pkt, struct ospf_iface *ifa,
       if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
       {
        tm_stop(n->dbdes_timer);
+       ospf_reset_ldd(p, n);
        ospf_neigh_sm(n, INM_EXDONE);
        break;
       }
@@ -457,7 +466,11 @@ ospf_receive_dbdes(struct ospf_packet *pkt, struct ospf_iface *ifa,
       ospf_send_dbdes(p, n);
 
       if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
+      {
+       /* Use dbdes timer to postpone freeing of Last DBDES packet buffer */
+       tm_start(n->dbdes_timer, n->ifa->deadint S);
        ospf_neigh_sm(n, INM_EXDONE);
+      }
     }
     break;
 

diff --git a/proto/ospf/neighbor.c b/proto/ospf/neighbor.c
index 54d643c65e550f9b87254627a988d4c0175cc928..c143b1306fa94a16cc0ef4828f777c42f3e70f1b 100644 (file)
--- a/proto/ospf/neighbor.c
+++ b/proto/ospf/neighbor.c
@@ -608,6 +608,12 @@ dbdes_timer_hook(timer *t)
 
   if ((n->state == NEIGHBOR_EXCHANGE) && (n->myimms & DBDES_MS))
     ospf_rxmt_dbdes(p, n);
+
+  if ((n->state > NEIGHBOR_LOADING) && !(n->myimms & DBDES_MS))
+  {
+    ospf_reset_ldd(p, n);
+    tm_stop(n->dbdes_timer);
+  }
 }
 
 static void

diff --git a/proto/ospf/ospf.h b/proto/ospf/ospf.h
index 23289ccd503c88c4f4d73abfaa9705eeb240b320..d3f12738907d6815c87be7c04a1a620300360543 100644 (file)
--- a/proto/ospf/ospf.h
+++ b/proto/ospf/ospf.h
@@ -1041,6 +1041,7 @@ uint ospf_hello3_options(struct ospf_packet *pkt);
 /* dbdes.c */
 void ospf_send_dbdes(struct ospf_proto *p, struct ospf_neighbor *n);
 void ospf_rxmt_dbdes(struct ospf_proto *p, struct ospf_neighbor *n);
+void ospf_reset_ldd(struct ospf_proto *p, struct ospf_neighbor *n);
 void ospf_receive_dbdes(struct ospf_packet *pkt, struct ospf_iface *ifa, struct ospf_neighbor *n);
 uint ospf_dbdes3_options(struct ospf_packet *pkt);