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 e74baa823dece0844c620879ca4f3feb6bf8ff42..3c22850871ce3da378f41585ccceb9ad05e82a1c 100644 (file)
--- a/proto/ospf/dbdes.c
+++ b/proto/ospf/dbdes.c
@@ -235,6 +235,14 @@ 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)
 {
@@ -433,6 +441,7 @@ 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;
       }
@@ -456,7 +465,11 @@ 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 9239894ecbc687474315468bc8ec3470dde9ddb9..6d2f1fb2e401a745bade894165ee43b3a4359c53 100644 (file)
--- a/proto/ospf/neighbor.c
+++ b/proto/ospf/neighbor.c
@@ -610,6 +610,12 @@ 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 35fd667221d6bd143cc7825fdf2810ee23b99ca9..6a20300e523f9be2c270526d0611e8dca3589d6d 100644 (file)
--- a/proto/ospf/ospf.h
+++ b/proto/ospf/ospf.h
@@ -989,6 +989,7 @@ void ospf_receive_hello(struct ospf_packet *pkt, struct ospf_iface *ifa, struct
 /* 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);
 
 /* lsreq.c */