Vastly improved OSPF reconfiguration.

Now it can handle a change in iface pattern structure.
It can add, remove and reconfigure interfaces, vlinks and areas.

12 files changed, 690 insertions, 528 deletions

diff --git a/proto/ospf/config.Y b/proto/ospf/config.Y
index 321bd8d4..f3a87d66 100644
--- a/proto/ospf/config.Y
+++ b/proto/ospf/config.Y
@@ -22,8 +22,13 @@ static struct ospf_stubnet_config *this_stubnet;
 
 #ifdef OSPFv2
 static void
-finish_iface_config(struct ospf_iface_patt *ip)
+ospf_iface_finish(void)
 {
+  struct ospf_iface_patt *ip = OSPF_PATT;
+
+  if (ip->deadint == 0)
+    ip->deadint = ip->deadc * ip->helloint;
+
   ip->passwords = get_passwords();
 
   if ((ip->autype == OSPF_AUTH_CRYPT) && (ip->helloint < 5))
@@ -36,13 +41,57 @@ finish_iface_config(struct ospf_iface_patt *ip)
 
 #ifdef OSPFv3
 static void
-finish_iface_config(struct ospf_iface_patt *ip)
+ospf_iface_finish(void)
 {
+  struct ospf_iface_patt *ip = OSPF_PATT;
+
+  if (ip->deadint == 0)
+    ip->deadint = ip->deadc * ip->helloint;
+
   if ((ip->autype != OSPF_AUTH_NONE) || (get_passwords() != NULL))
     cf_error("Authentication not supported in OSPFv3");
 }
 #endif
 
+static void
+ospf_area_finish(void)
+{
+  if ((this_area->areaid == 0) && (this_area->stub != 0))
+    cf_error( "Backbone area cannot be stub");
+}
+
+static void
+ospf_proto_finish(void)
+{
+  struct ospf_config *cf = OSPF_CFG;
+
+  if (EMPTY_LIST(cf->area_list))
+    cf_error( "No configured areas in OSPF");
+
+  int areano = 0;
+  int backbone = 0;
+  struct ospf_area_config *ac;
+  WALK_LIST(ac, cf->area_list)
+  {
+    areano++;
+    if (ac->areaid == 0)
+     backbone = 1;
+  }
+  cf->abr = areano > 1;
+
+  if (cf->abr && !backbone)
+  {
+    struct ospf_area_config *ac = cfg_allocz(sizeof(struct ospf_area_config));
+    add_head(&cf->area_list, NODE ac);
+    init_list(&ac->patt_list);
+    init_list(&ac->net_list);
+    init_list(&ac->stubnet_list);
+  }
+
+  if (!cf->abr && !EMPTY_LIST(cf->vlink_list))
+    cf_error( "No configured areas in OSPF");
+}
+
 CF_DECLS
 
 CF_KEYWORDS(OSPF, AREA, OSPF_METRIC1, OSPF_METRIC2, OSPF_TAG, OSPF_ROUTER_ID)
@@ -58,12 +107,13 @@ CF_KEYWORDS(WAIT, DELAY, LSADB, ECMP, LIMIT, WEIGHT)
 
 CF_GRAMMAR
 
-CF_ADDTO(proto, ospf_proto '}')
+CF_ADDTO(proto, ospf_proto '}' { ospf_proto_finish(); } )
 
 ospf_proto_start: proto_start OSPF {
      this_proto = proto_config_new(&proto_ospf, sizeof(struct ospf_config));
      this_proto->preference = DEF_PREF_OSPF;
      init_list(&OSPF_CFG->area_list);
+     init_list(&OSPF_CFG->vlink_list);
      OSPF_CFG->rfc1583 = DEFAULT_RFC1583;
      OSPF_CFG->tick = DEFAULT_OSPFTICK;
   }
@@ -80,22 +130,21 @@ ospf_proto_item:
  | ECMP bool { OSPF_CFG->ecmp = $2 ? DEFAULT_ECMP_LIMIT : 0; }
  | ECMP bool LIMIT expr { OSPF_CFG->ecmp = $2 ? $4 : 0; if ($4 < 0) cf_error("ECMP limit cannot be negative"); }
  | TICK expr { OSPF_CFG->tick = $2; if($2<=0) cf_error("Tick must be greater than zero"); }
- | ospf_area '}'
+ | ospf_area
  ;
 
-ospf_area_start: AREA idval '{' {
+ospf_area_start: AREA idval {
   this_area = cfg_allocz(sizeof(struct ospf_area_config));
   add_tail(&OSPF_CFG->area_list, NODE this_area);
   this_area->areaid = $2;
   this_area->stub = 0;
   init_list(&this_area->patt_list);
-  init_list(&this_area->vlink_list);
   init_list(&this_area->net_list);
   init_list(&this_area->stubnet_list);
  }
  ;
 
-ospf_area: ospf_area_start ospf_area_opts
+ospf_area: ospf_area_start '{' ospf_area_opts '}' { ospf_area_finish(); }
  ;
 
 ospf_area_opts:
@@ -138,7 +187,7 @@ ospf_stubnet_item:
  ;
 
 ospf_vlink:
-   ospf_vlink_start '{' ospf_vlink_opts '}' { finish_iface_config(OSPF_PATT); }
+   ospf_vlink_start '{' ospf_vlink_opts '}' { ospf_iface_finish(); }
  | ospf_vlink_start
  ;
 
@@ -152,7 +201,7 @@ ospf_vlink_item:
  | RETRANSMIT expr { OSPF_PATT->rxmtint = $2 ; if ($2<=0) cf_error("Retransmit int must be greater than zero"); }
  | TRANSMIT DELAY expr { OSPF_PATT->inftransdelay = $3 ; if (($3<=0) || ($3>65535)) cf_error("Transmit delay must be in range 1-65535"); }
  | WAIT expr { OSPF_PATT->waitint = $2 ; }
- | DEAD expr { OSPF_PATT->dead = $2 ; if ($2<=1) cf_error("Dead interval must be greater than one"); }
+ | DEAD expr { OSPF_PATT->deadint = $2 ; if ($2<=1) cf_error("Dead interval must be greater than one"); }
  | DEAD COUNT expr { OSPF_PATT->deadc = $3 ; if ($3<=1) cf_error("Dead count must be greater than one"); }
  | AUTHENTICATION NONE { OSPF_PATT->autype = OSPF_AUTH_NONE ; }
  | AUTHENTICATION SIMPLE { OSPF_PATT->autype = OSPF_AUTH_SIMPLE ; }
@@ -164,15 +213,16 @@ ospf_vlink_start: VIRTUAL LINK idval
  {
   if (this_area->areaid == 0) cf_error("Virtual link cannot be in backbone");
   this_ipatt = cfg_allocz(sizeof(struct ospf_iface_patt));
-  add_tail(&this_area->vlink_list, NODE this_ipatt);
+  add_tail(&OSPF_CFG->vlink_list, NODE this_ipatt);
   init_list(&this_ipatt->ipn_list);
+  OSPF_PATT->voa = this_area->areaid;
   OSPF_PATT->vid = $3;
   OSPF_PATT->helloint = HELLOINT_D;
   OSPF_PATT->rxmtint = RXMTINT_D;
   OSPF_PATT->inftransdelay = INFTRANSDELAY_D;
   OSPF_PATT->waitint = WAIT_DMH*HELLOINT_D;
   OSPF_PATT->deadc = DEADC_D;
-  OSPF_PATT->dead = 0;
+  OSPF_PATT->deadint = 0;
   OSPF_PATT->type = OSPF_IT_VLINK;
   init_list(&OSPF_PATT->nbma_list);
   OSPF_PATT->autype = OSPF_AUTH_NONE;
@@ -185,10 +235,8 @@ ospf_iface_item:
  | HELLO expr { OSPF_PATT->helloint = $2 ; if (($2<=0) || ($2>65535)) cf_error("Hello interval must be in range 1-65535"); }
  | POLL expr { OSPF_PATT->pollint = $2 ; if ($2<=0) cf_error("Poll int must be greater than zero"); }
  | RETRANSMIT expr { OSPF_PATT->rxmtint = $2 ; if ($2<=0) cf_error("Retransmit int must be greater than zero"); }
- | TRANSMIT DELAY expr { OSPF_PATT->inftransdelay = $3 ; if (($3<=0) || ($3>65535)) cf_error("Transmit delay must be in range 1-65535"); }
- | PRIORITY expr { OSPF_PATT->priority = $2 ; if (($2<0) || ($2>255)) cf_error("Priority must be in range 0-255"); }
  | WAIT expr { OSPF_PATT->waitint = $2 ; }
- | DEAD expr { OSPF_PATT->dead = $2 ; if ($2<=1) cf_error("Dead interval must be greater than one"); }
+ | DEAD expr { OSPF_PATT->deadint = $2 ; if ($2<=1) cf_error("Dead interval must be greater than one"); }
  | DEAD COUNT expr { OSPF_PATT->deadc = $3 ; if ($3<=1) cf_error("Dead count must be greater than one"); }
  | TYPE BROADCAST { OSPF_PATT->type = OSPF_IT_BCAST ; }
  | TYPE BCAST { OSPF_PATT->type = OSPF_IT_BCAST ; }
@@ -198,6 +246,8 @@ ospf_iface_item:
  | TYPE PTP { OSPF_PATT->type = OSPF_IT_PTP ; }
  | TYPE POINTOMULTIPOINT { OSPF_PATT->type = OSPF_IT_PTMP ; }
  | TYPE PTMP { OSPF_PATT->type = OSPF_IT_PTMP ; }
+ | TRANSMIT DELAY expr { OSPF_PATT->inftransdelay = $3 ; if (($3<=0) || ($3>65535)) cf_error("Transmit delay must be in range 1-65535"); }
+ | PRIORITY expr { OSPF_PATT->priority = $2 ; if (($2<0) || ($2>255)) cf_error("Priority must be in range 0-255"); }
  | STRICT NONBROADCAST bool { OSPF_PATT->strictnbma = $3 ; }
  | STUB bool { OSPF_PATT->stub = $2 ; }
  | CHECK LINK bool { OSPF_PATT->check_link = $3; }
@@ -281,7 +331,7 @@ ospf_iface_start:
   OSPF_PATT->priority = PRIORITY_D;
   OSPF_PATT->waitint = WAIT_DMH*HELLOINT_D;
   OSPF_PATT->deadc = DEADC_D;
-  OSPF_PATT->dead = 0;
+  OSPF_PATT->deadint = 0;
   OSPF_PATT->type = OSPF_IT_UNDEF;
   init_list(&OSPF_PATT->nbma_list);
   OSPF_PATT->autype = OSPF_AUTH_NONE;
@@ -300,7 +350,7 @@ ospf_iface_opt_list:
  ;
 
 ospf_iface:
-  ospf_iface_start iface_patt_list ospf_iface_opt_list { finish_iface_config(OSPF_PATT); }
+  ospf_iface_start iface_patt_list ospf_iface_opt_list { ospf_iface_finish(); }
  ;
 
 opttext:
diff --git a/proto/ospf/hello.c b/proto/ospf/hello.c
index 47b84a4d..76c95c4f 100644
--- a/proto/ospf/hello.c
+++ b/proto/ospf/hello.c
@@ -88,7 +88,7 @@ ospf_hello_receive(struct ospf_packet *ps_i, struct ospf_iface *ifa,
 #else /* OSPFv3 */
   tmp = ntohs(ps->deadint);
 #endif
-  if (tmp != ifa->dead)
+  if (tmp != ifa->deadint)
   {
     log(L_ERR "%s%I - dead interval mismatch (%d)", beg, faddr, tmp);
     return;
@@ -217,13 +217,13 @@ ospf_hello_receive(struct ospf_packet *ps_i, struct ospf_iface *ifa,
   if (ifa->type == OSPF_IT_NBMA)
   {
     if ((ifa->priority == 0) && (n->priority > 0))
-      ospf_hello_send(NULL, 0, n);
+      ospf_hello_send(NULL, OHS_HELLO, n);
   }
   ospf_neigh_sm(n, INM_HELLOREC);
 }
 
 void
-ospf_hello_send(timer *timer, int poll, struct ospf_neighbor *dirn)
+ospf_hello_send(timer *timer, int kind, struct ospf_neighbor *dirn)
 {
   struct ospf_iface *ifa;
   struct ospf_hello_packet *pkt;
@@ -231,7 +231,6 @@ ospf_hello_send(timer *timer, int poll, struct ospf_neighbor *dirn)
   struct proto *p;
   struct ospf_neighbor *neigh, *n1;
   u16 length;
-  u32 *pp;
   int i;
   struct nbma_node *nb;
 
@@ -276,27 +275,31 @@ ospf_hello_send(timer *timer, int poll, struct ospf_neighbor *dirn)
   pkt->options = ifa->oa->options;
 
 #ifdef OSPFv2
-  pkt->deadint = htonl(ifa->dead);
+  pkt->deadint = htonl(ifa->deadint);
   pkt->dr = htonl(ipa_to_u32(ifa->drip));
   pkt->bdr = htonl(ipa_to_u32(ifa->bdrip));
 #else /* OSPFv3 */
-  pkt->deadint = htons(ifa->dead);
+  pkt->deadint = htons(ifa->deadint);
   pkt->dr = htonl(ifa->drid);
   pkt->bdr = htonl(ifa->bdrid);
 #endif
 
   /* Fill all neighbors */
   i = 0;
-  pp = (u32 *) (((u8 *) pkt) + sizeof(struct ospf_hello_packet));
-  WALK_LIST(neigh, ifa->neigh_list)
+
+  if (kind != OHS_SHUTDOWN)
   {
-    if ((i+1) * sizeof(u32) + sizeof(struct ospf_hello_packet) > ospf_pkt_bufsize(ifa))
+    u32 *pp = (u32 *) (((u8 *) pkt) + sizeof(struct ospf_hello_packet));
+    WALK_LIST(neigh, ifa->neigh_list)
     {
-      OSPF_TRACE(D_PACKETS, "Too many neighbors on the interface!");
-      break;
+      if ((i+1) * sizeof(u32) + sizeof(struct ospf_hello_packet) > ospf_pkt_bufsize(ifa))
+      {
+	log(L_WARN "%s: Too many neighbors on interface %s", p->name, ifa->iface->name);
+	break;
+      }
+      *(pp + i) = htonl(neigh->rid);
+      i++;
     }
-    *(pp + i) = htonl(neigh->rid);
-    i++;
   }
 
   length = sizeof(struct ospf_hello_packet) + i * sizeof(u32);
@@ -319,7 +322,7 @@ ospf_hello_send(timer *timer, int poll, struct ospf_neighbor *dirn)
     int to_all = ifa->state > OSPF_IS_DROTHER;
     int me_elig = ifa->priority > 0;
  
-    if (poll)			/* Poll timer */
+    if (kind == OHS_POLL)	/* Poll timer */
     {
       WALK_LIST(nb, ifa->nbma_list)
 	if (!nb->found && (to_all || (me_elig && nb->eligible)))
diff --git a/proto/ospf/hello.h b/proto/ospf/hello.h
index 5d73c09e..3675c052 100644
--- a/proto/ospf/hello.h
+++ b/proto/ospf/hello.h
@@ -12,6 +12,10 @@
 
 void ospf_hello_receive(struct ospf_packet *ps_i, struct ospf_iface *ifa,
 			struct ospf_neighbor *n, ip_addr faddr);
-void ospf_hello_send(timer *timer, int poll, struct ospf_neighbor *dirn);
+void ospf_hello_send(timer *timer, int kind, struct ospf_neighbor *dirn);
+
+#define OHS_HELLO    0
+#define OHS_POLL     1
+#define OHS_SHUTDOWN 2
 
 #endif /* _BIRD_OSPF_HELLO_H_ */
diff --git a/proto/ospf/iface.c b/proto/ospf/iface.c
index e7c9e72d..faee634a 100644
--- a/proto/ospf/iface.c
+++ b/proto/ospf/iface.c
@@ -21,13 +21,13 @@ char *ospf_it[] = { "broadcast", "nbma", "ptp", "ptmp", "virtual link" };
 static void
 poll_timer_hook(timer * timer)
 {
-  ospf_hello_send(timer, 1, NULL);
+  ospf_hello_send(timer, OHS_POLL, NULL);
 }
 
 static void
 hello_timer_hook(timer * timer)
 {
-  ospf_hello_send(timer, 0, NULL);
+  ospf_hello_send(timer, OHS_HELLO, NULL);
 }
 
 static void
@@ -40,6 +40,8 @@ wait_timer_hook(timer * timer)
   ospf_iface_sm(ifa, ISM_WAITF);
 }
 
+static void ospf_iface_change_mtu(struct proto_ospf *po, struct ospf_iface *ifa);
+
 u32
 rxbufsize(struct ospf_iface *ifa)
 {
@@ -163,7 +165,13 @@ ospf_iface_down(struct ospf_iface *ifa)
 
   if (ifa->type != OSPF_IT_VLINK)
   {
-    OSPF_TRACE(D_EVENTS, "Removing interface %s", ifa->iface->name);
+#ifdef OSPFv2
+    OSPF_TRACE(D_EVENTS, "Removing interface %s (%I/%d) from area %R",
+	       ifa->iface->name, ifa->addr->prefix, ifa->addr->pxlen, ifa->oa->areaid);
+#else
+    OSPF_TRACE(D_EVENTS, "Removing interface %s (IID %d) from area %R",
+	       ifa->iface->name, ifa->instance_id, ifa->oa->areaid);
+#endif
 
     /* First of all kill all the related vlinks */
     WALK_LIST(iff, po->iface_list)
@@ -207,14 +215,25 @@ ospf_iface_down(struct ospf_iface *ifa)
 }
 
 
-static void
+void
 ospf_iface_remove(struct ospf_iface *ifa)
 {
+  struct proto *p = &ifa->oa->po->proto;
+  if (ifa->type == OSPF_IT_VLINK)
+    OSPF_TRACE(D_EVENTS, "Removing vlink to %R via area %R", ifa->vid, ifa->voa->areaid);
+
   ospf_iface_sm(ifa, ISM_DOWN);
   rem_node(NODE ifa);
   rfree(ifa->pool);
 }
 
+void
+ospf_iface_shutdown(struct ospf_iface *ifa)
+{
+  if (ifa->state > OSPF_IS_DOWN)
+    ospf_hello_send(ifa->hello_timer, OHS_SHUTDOWN, NULL);
+}
+
 /**
  * ospf_iface_chstate - handle changes of interface state
  * @ifa: OSPF interface
@@ -357,7 +376,7 @@ ospf_iface_sm(struct ospf_iface *ifa, int event)
 }
 
 static u8
-ospf_iface_classify(struct iface *ifa, struct ifa *addr)
+ospf_iface_classify_int(struct iface *ifa, struct ifa *addr)
 {
   if (ipa_nonzero(addr->opposite))
     return (ifa->flags & IF_MULTICAST) ? OSPF_IT_PTP :  OSPF_IT_PTMP;
@@ -372,6 +391,13 @@ ospf_iface_classify(struct iface *ifa, struct ifa *addr)
   return OSPF_IT_PTP;
 }
 
+static inline u8
+ospf_iface_classify(u8 type, struct ifa *addr)
+{
+  return (type != OSPF_IT_UNDEF) ? type : ospf_iface_classify_int(addr->iface, addr);
+}
+
+
 struct ospf_iface *
 ospf_iface_find(struct proto_ospf *p, struct iface *what)
 {
@@ -401,23 +427,69 @@ ospf_iface_add(struct object_lock *lock)
   ospf_iface_sm(ifa, (ifa->check_link && !(ifa->iface->flags & IF_LINK_UP)) ? ISM_LOOP : ISM_UP);
 }
 
+static inline void
+add_nbma_node(struct ospf_iface *ifa, struct nbma_node *src, int found)
+{
+  struct nbma_node *n = mb_alloc(ifa->pool, sizeof(struct nbma_node));
+  add_tail(&ifa->nbma_list, NODE n);
+  n->ip = src->ip;
+  n->eligible = src->eligible;
+  n->found = found;
+}
+
+static int
+ospf_iface_stubby(struct ospf_iface_patt *ip, struct ifa *addr)
+{
+  if (! addr)
+    return 0;
+
+  /*
+   * We cannot properly support multiple OSPF ifaces on real iface
+   * with multiple prefixes, therefore we force OSPF ifaces with
+   * non-primary IP prefixes to be stub.
+   */
+#if defined(OSPFv2) && !defined(CONFIG_MC_PROPER_SRC)
+  if (! (addr->flags & IA_PRIMARY))
+    return 1;
+#endif
+
+  /* a loopback/dummy address */
+  if ((addr->pxlen == MAX_PREFIX_LENGTH) && ipa_zero(addr->opposite))
+    return 1;
+
+  return ip->stub;
+}
+
 void
-ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr,
-	       struct ospf_area_config *ac, struct ospf_iface_patt *ip)
+ospf_iface_new(struct ospf_area *oa, struct ifa *addr, struct ospf_iface_patt *ip)
 {
-  struct proto *p = &po->proto;
-  struct pool *pool = rp_new(p->pool, "OSPF Interface");
+  struct proto *p = &oa->po->proto;
+  struct iface *iface = addr ? addr->iface : NULL;
+  struct pool *pool;
+
   struct ospf_iface *ifa;
-  struct nbma_node *nbma, *nb;
+  struct nbma_node *nb;
   struct object_lock *lock;
-  struct ospf_area *oa;
 
-  if (ip->type != OSPF_IT_VLINK)
-    OSPF_TRACE(D_EVENTS, "Adding interface %s", iface->name);
+  if (ip->type == OSPF_IT_VLINK)
+    OSPF_TRACE(D_EVENTS, "Adding vlink to %R via area %R", ip->vid, ip->voa);
+  else
+  {
+#ifdef OSPFv2
+    OSPF_TRACE(D_EVENTS, "Adding interface %s (%I/%d) to area %R",
+	       iface->name, addr->prefix, addr->pxlen, oa->areaid);
+#else
+    OSPF_TRACE(D_EVENTS, "Adding interface %s (IID %d) to area %R",
+	       iface->name, ip->instance_id, oa->areaid);
+#endif
+  }
 
+  pool = rp_new(p->pool, "OSPF Interface");
   ifa = mb_allocz(pool, sizeof(struct ospf_iface));
   ifa->iface = iface;
   ifa->addr = addr;
+  ifa->oa = oa;
+  ifa->cf = ip;
   ifa->pool = pool;
 
   ifa->cost = ip->cost;
@@ -428,7 +500,7 @@ ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr,
   ifa->pollint = ip->pollint;
   ifa->strictnbma = ip->strictnbma;
   ifa->waitint = ip->waitint;
-  ifa->dead = (ip->dead == 0) ? ip->deadc * ifa->helloint : ip->dead;
+  ifa->deadint = ip->deadint;
   ifa->stub = ospf_iface_stubby(ip, addr);
   ifa->ioprob = OSPF_I_OK;
   ifa->rxbuf = ip->rxbuf;
@@ -444,14 +516,7 @@ ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr,
   ifa->instance_id = ip->instance_id;
 #endif
 
-  if (ip->type == OSPF_IT_UNDEF)
-    ifa->type = ospf_iface_classify(iface, addr);
-  else
-    ifa->type = ip->type;
-
-  /* a loopback/dummy address */
-  if ((addr->pxlen == MAX_PREFIX_LENGTH) && ipa_zero(addr->opposite))
-    ifa->stub = 1;
+  ifa->type = ospf_iface_classify(ip->type, addr);
 
   /* Check validity of interface type */
   int old_type = ifa->type;
@@ -479,16 +544,8 @@ ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr,
   init_list(&ifa->nbma_list);
 
   WALK_LIST(nb, ip->nbma_list)
-  {
-    if (!ipa_in_net(nb->ip, addr->prefix, addr->pxlen))
-      continue;
-
-    nbma = mb_alloc(pool, sizeof(struct nbma_node));
-    nbma->ip = nb->ip;
-    nbma->eligible = nb->eligible;
-    nbma->found = 0;
-    add_tail(&ifa->nbma_list, NODE nbma);
-  }
+    if (ipa_in_net(nb->ip, addr->prefix, addr->pxlen))
+      add_nbma_node(ifa, nb, 0);
 
   DBG("%s: Installing hello timer. (%u)\n", p->name, ifa->helloint);
   ifa->hello_timer = tm_new(pool);
@@ -518,26 +575,11 @@ ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr,
   }
 
   ifa->state = OSPF_IS_DOWN;
-  add_tail(&po->iface_list, NODE ifa);
-
-  ifa->oa = NULL;
-  WALK_LIST(oa, po->area_list)
-  {
-    if (oa->areaid == ac->areaid)
-    {
-      ifa->oa = oa;
-      break;
-    }
-  }
-
-  if (!ifa->oa)
-    bug("Cannot add any area to accepted Interface");
-  else
+  add_tail(&oa->po->iface_list, NODE ifa);
 
   if (ifa->type == OSPF_IT_VLINK)
   {
-    ifa->oa = po->backbone;
-    ifa->voa = oa;
+    ifa->voa = ospf_find_area(oa->po, ip->voa);
     ifa->vid = ip->vid;
     return;			/* Don't lock, don't add sockets */
   }
@@ -564,14 +606,209 @@ ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr,
   olock_acquire(lock);
 }
 
+int
+ospf_iface_reconfigure(struct ospf_iface *ifa, struct ospf_iface_patt *new)
+{
+  struct proto *p = &ifa->oa->po->proto;
+  struct nbma_node *nb, *nbx;
+  char *ifname = (ifa->type != OSPF_IT_VLINK) ? ifa->iface->name : "vlink";
+
+  /* Type could be changed in ospf_iface_new(),
+     but if config values are same then also results are same */
+  int old_type = ospf_iface_classify(ifa->cf->type, ifa->addr);
+  int new_type = ospf_iface_classify(new->type, ifa->addr);
+  if (old_type != new_type)
+    return 0;
+
+  int new_stub = ospf_iface_stubby(new, ifa->addr);
+  if (ifa->stub != new_stub)
+    return 0;
+
+  ifa->cf = new;
+  ifa->marked = 0;
+
+
+  /* HELLO TIMER */
+  if (ifa->helloint != new->helloint)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing hello interval on interface %s from %d to %d",
+	       ifname, ifa->helloint, new->helloint);
+
+    ifa->helloint = new->helloint;
+    ifa->hello_timer->recurrent = ifa->helloint;
+    tm_start(ifa->hello_timer, ifa->helloint);
+  }
+
+  /* RXMT TIMER */
+  if (ifa->rxmtint != new->rxmtint)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing retransmit interval on interface %s from %d to %d",
+	       ifname, ifa->rxmtint, new->rxmtint);
+
+    ifa->rxmtint = new->rxmtint;
+  }
+
+  /* POLL TIMER */
+  if (ifa->pollint != new->pollint)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing poll interval on interface %s from %d to %d",
+	       ifname, ifa->pollint, new->pollint);
+
+    ifa->pollint = new->helloint;
+    ifa->poll_timer->recurrent = ifa->pollint;
+    tm_start(ifa->poll_timer, ifa->pollint);
+  }
+
+  /* WAIT TIMER */
+  if (ifa->waitint != new->waitint)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing wait interval on interface %s from %d to %d",
+	       ifname, ifa->waitint, new->waitint);
+
+    ifa->waitint = new->waitint;
+    if (ifa->wait_timer->expires != 0)
+      tm_start(ifa->wait_timer, ifa->waitint);
+  }
+
+  /* DEAD TIMER */
+  if (ifa->deadint != new->deadint)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing dead interval on interface %s from %d to %d",
+	       ifname, ifa->deadint, new->deadint);
+    ifa->deadint = new->deadint;
+  }
+
+  /* INFTRANS */
+  if (ifa->inftransdelay != new->inftransdelay)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing transmit delay on interface %s from %d to %d",
+		     ifname, ifa->inftransdelay, new->inftransdelay);
+    ifa->inftransdelay = new->inftransdelay;
+  }
+
+#ifdef OSPFv2	
+  /* AUTHENTICATION */
+  if (ifa->autype != new->autype)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing authentication type on interface %s", ifname);
+    ifa->autype = new->autype;
+  }
+
+  /* Update passwords */
+  ifa->passwords = new->passwords;
+#endif
+
+  /* Remaining options are just for proper interfaces */
+  if (ifa->type == OSPF_IT_VLINK)
+    return 1;
+
+
+  /* COST */
+  if (ifa->cost != new->cost)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing cost on interface %s from %d to %d",
+	       ifname, ifa->cost, new->cost);
+
+    ifa->cost = new->cost;
+  }
+
+  /* PRIORITY */
+  if (ifa->priority != new->priority)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing priority on interface %s from %d to %d",
+	       ifname, ifa->priority, new->priority);
+    ifa->priority = new->priority;
+  }
+
+  /* STRICT NBMA */
+  if (ifa->strictnbma != new->strictnbma)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing NBMA strictness on interface %s", ifname);
+    ifa->strictnbma = new->strictnbma;
+  }
+
+  /* NBMA LIST - remove or update old */
+  WALK_LIST_DELSAFE(nb, nbx, ifa->nbma_list)
+  {
+    struct nbma_node *nb2 = find_nbma_node_in(&new->nbma_list, nb->ip);
+    if (nb2)
+    {
+      if (nb->eligible != nb2->eligible)
+      {
+	OSPF_TRACE(D_EVENTS, "Changing eligibility of neighbor %I on interface %s",
+		   nb->ip, ifname);
+	nb->eligible = nb2->eligible;
+      }
+    }
+    else
+    {
+      OSPF_TRACE(D_EVENTS, "Removing NBMA neighbor %I on interface %s",
+		       nb->ip, ifname);
+      rem_node(NODE nb);
+      mb_free(nb);
+    }
+  }
+
+  /* NBMA LIST - add new */
+  WALK_LIST(nb, new->nbma_list)
+  {
+    if (!ipa_in_net(nb->ip, ifa->addr->prefix, ifa->addr->pxlen))
+      continue;
+
+    if (! find_nbma_node(ifa, nb->ip))
+    {
+      OSPF_TRACE(D_EVENTS, "Adding NBMA neighbor %I on interface %s",
+		 nb->ip, ifname);
+      add_nbma_node(ifa, nb, !!find_neigh_by_ip(ifa, nb->ip));
+    }
+  }
+
+  /* RX BUFF */
+  if (ifa->rxbuf != new->rxbuf)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing rxbuf interface %s from %d to %d",
+	       ifname, ifa->rxbuf, new->rxbuf);
+    ifa->rxbuf = new->rxbuf;
+    ospf_iface_change_mtu(ifa->oa->po, ifa);
+  }
+
+  /* LINK */
+  if (ifa->check_link != new->check_link)
+  {
+    OSPF_TRACE(D_EVENTS, "%s link check on interface %s",
+	       new->check_link ? "Enabling" : "Disabling", ifname);
+    ifa->check_link = new->check_link;
+
+    if (!(ifa->iface->flags & IF_LINK_UP))
+      ospf_iface_sm(ifa, ifa->check_link ? ISM_LOOP : ISM_UNLOOP);
+  }
+
+  /* ECMP weight */
+  if (ifa->ecmp_weight != new->ecmp_weight)
+  {
+    OSPF_TRACE(D_EVENTS, "Changing ECMP weight of interface %s from %d to %d",
+	       ifname, (int)ifa->ecmp_weight + 1, (int)new->ecmp_weight + 1);
+    ifa->ecmp_weight = new->ecmp_weight;
+  }
+
+  /* instance_id is not updated - it is part of key */
+
+  return 1;
+}
+
 
 #ifdef OSPFv2
 
+static inline struct ospf_iface_patt *
+ospf_iface_patt_find(struct ospf_area_config *ac, struct ifa *a)
+{
+  return (struct ospf_iface_patt *) iface_patt_find(&ac->patt_list, a->iface, a);
+}
+
 void
 ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a)
 {
   struct proto_ospf *po = (struct proto_ospf *) p;
-  struct ospf_config *cf = (struct ospf_config *) (p->cf);
 
   if (a->flags & IA_SECONDARY)
     return;
@@ -583,16 +820,14 @@ ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a)
   if (flags & IF_CHANGE_UP)
   {
     int done = 0;
-    struct ospf_area_config *ac;
-    WALK_LIST(ac, cf->area_list)
+    struct ospf_area *oa;
+    WALK_LIST(oa, po->area_list)
     {
-      struct ospf_iface_patt *ip = (struct ospf_iface_patt *)
-	iface_patt_find(&ac->patt_list, a->iface, a);
-
-      if (ip)
+      struct ospf_iface_patt *ip;
+      if (ip = ospf_iface_patt_find(oa->ac, a))
       {
 	if (!done)
-	  ospf_iface_new(po, a->iface, a, ac, ip);
+	  ospf_iface_new(oa, a, ip);
 	done++;
       }
     }
@@ -613,23 +848,72 @@ ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a)
   }
 }
 
-#else /* OSPFv3 */
+static struct ospf_iface *
+ospf_iface_find_by_key(struct ospf_area *oa, struct ifa *a)
+{
+  struct ospf_iface *ifa;
+  WALK_LIST(ifa, oa->po->iface_list)
+    if ((ifa->addr == a) && (ifa->oa == oa) && (ifa->type != OSPF_IT_VLINK))
+      return ifa;
+
+  return NULL;
+}
 
-static inline int iflag_test(u32 *a, u8 i)
+void
+ospf_ifaces_reconfigure(struct ospf_area *oa, struct ospf_area_config *nac)
 {
-  return a[i / 32] & (1u << (i % 32));
+  struct ospf_iface_patt *ip;
+  struct iface *iface;
+  struct ifa *a;
+
+  WALK_LIST(iface, iface_list)
+    WALK_LIST(a, iface->addrs)
+    {
+      if (a->flags & IA_SECONDARY)
+	continue;
+
+      if (a->scope <= SCOPE_LINK)
+	continue;
+
+      if (ip = ospf_iface_patt_find(oa->ac, a))
+      {
+	/* Main inner loop */
+	struct ospf_iface *ifa = ospf_iface_find_by_key(oa, a);
+	if (ifa)
+	{
+	  if (ospf_iface_reconfigure(ifa, ip))
+	    continue;
+
+	  /* Hard restart */
+	  ospf_iface_shutdown(ifa);
+	  ospf_iface_remove(ifa);
+	}
+	
+	ospf_iface_new(oa, a, ip);
+      }
+    }
 }
 
-static inline void iflag_set(u32 *a, u8 i)
+
+#else /* OSPFv3 */
+
+struct ospf_iface_patt *
+ospf_iface_patt_find(struct ospf_area_config *ac, struct iface *iface, int iid)
 {
-  a[i / 32] |= (1u << (i % 32));
+  struct ospf_iface_patt *pt, *res = NULL;
+
+  WALK_LIST(pt, ac->patt_list)
+    if ((pt->instance_id >= iid) && (iface_patt_match(&pt->i, iface, NULL)) &&
+	(!res || (pt->instance_id < res->instance_id)))
+      res = pt;
+
+  return res;
 }
 
 void
 ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a)
 {
   struct proto_ospf *po = (struct proto_ospf *) p;
-  struct ospf_config *cf = (struct ospf_config *) (p->cf);
 
   if (a->flags & IA_SECONDARY)
     return;
@@ -643,40 +927,26 @@ ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a)
   {
     if (flags & IF_CHANGE_UP)
     {
-      u32 found_all[8] = {};
-      struct ospf_area_config *ac;
+      int done0 = 0;
+      struct ospf_area *oa;
 
-      WALK_LIST(ac, cf->area_list)
+      WALK_LIST(oa, po->area_list)
       {
-	u32 found_new[8] = {};
-	struct iface_patt *pt;
+	int iid = 0;
 
-	WALK_LIST(pt, ac->patt_list)
+	struct ospf_iface_patt *ip;
+	while (ip = ospf_iface_patt_find(oa->ac, a->iface, iid))
 	{
-	  if (iface_patt_match(pt, a->iface, a))
-	  {
-	    struct ospf_iface_patt *ipt = (struct ospf_iface_patt *) pt;
-
-	    /* If true, we already assigned that IID and we skip
-	       this to implement first-match behavior */
-	    if (iflag_test(found_new, ipt->instance_id))
-	      continue;
-
-	    /* If true, we already assigned that in a different area,
-	       we log collision */
-	    if (iflag_test(found_all, ipt->instance_id))
-	    {
-	      log(L_WARN "%s: Interface %s (IID %d) matches for multiple areas",
-		  p->name,  a->iface->name, ipt->instance_id);
-	      continue;
-	    }
-
-	    iflag_set(found_all, ipt->instance_id);
-	    iflag_set(found_new, ipt->instance_id);
-	    ospf_iface_new(po, a->iface, a, ac, ipt);
-	  }
+	  ospf_iface_new(oa, a, ip);
+	  if (ip->instance_id == 0)
+	    done0++;
+	  iid = ip->instance_id + 1;
 	}
       }
+
+      if (done0 > 1)
+	log(L_WARN "%s: Interface %s matches for multiple areas",
+	    p->name,  a->iface->name);
     }
 
     if (flags & IF_CHANGE_DOWN)
@@ -706,15 +976,64 @@ ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a)
   }
 }
 
-#endif
+static struct ospf_iface *
+ospf_iface_find_by_key(struct ospf_area *oa, struct ifa *a, int iid)
+{
+  struct ospf_iface *ifa;
+  WALK_LIST(ifa, oa->po->iface_list)
+    if ((ifa->addr == a) && (ifa->oa == oa) && (ifa->instance_id == iid) && (ifa->type != OSPF_IT_VLINK))
+      return ifa;
+
+  return NULL;
+}
 
 void
+ospf_ifaces_reconfigure(struct ospf_area *oa, struct ospf_area_config *nac)
+{
+  struct ospf_iface_patt *ip;
+  struct iface *iface;
+  struct ifa *a;
+
+  WALK_LIST(iface, iface_list)
+    WALK_LIST(a, iface->addrs)
+    {
+      if (a->flags & IA_SECONDARY)
+	continue;
+
+      if (a->scope != SCOPE_LINK)
+	continue;
+
+      int iid = 0;
+      while (ip = ospf_iface_patt_find(nac, iface, iid))
+      {
+	iid = ip->instance_id + 1;
+
+	/* Main inner loop */
+	struct ospf_iface *ifa = ospf_iface_find_by_key(oa, a, ip->instance_id);
+	if (ifa)
+	{
+	  if (ospf_iface_reconfigure(ifa, ip))
+	    continue;
+
+	  /* Hard restart */
+	  ospf_iface_shutdown(ifa);
+	  ospf_iface_remove(ifa);
+	}
+
+	ospf_iface_new(oa, a, ip);
+      }
+    }
+}
+
+#endif
+
+static void
 ospf_iface_change_mtu(struct proto_ospf *po, struct ospf_iface *ifa)
 {
   struct proto *p = &po->proto;
   struct ospf_packet *op;
   struct ospf_neighbor *n;
-  OSPF_TRACE(D_EVENTS, "Changing MTU on interface %s.", ifa->iface->name);
+  OSPF_TRACE(D_EVENTS, "Changing MTU on interface %s", ifa->iface->name);
 
   if (ifa->sk)
   {
@@ -755,11 +1074,13 @@ void
 ospf_if_notify(struct proto *p, unsigned flags, struct iface *iface)
 {
   struct proto_ospf *po = (struct proto_ospf *) p;
-    
+
+  /*
   if (iface->flags & IF_IGNORE)
     return;
+  */
 
-  /* Going up means that there are no such ifaces yet */ 
+  /* Going up means that there are no such ifaces yet */
   if (flags & IF_CHANGE_UP)
     return;
 
@@ -817,7 +1138,7 @@ ospf_iface_info(struct ospf_iface *ifa)
     cli_msg(-1015, "\tPoll timer: %u", ifa->pollint);
   }
   cli_msg(-1015, "\tWait timer: %u", ifa->waitint);
-  cli_msg(-1015, "\tDead timer: %u", ifa->dead);
+  cli_msg(-1015, "\tDead timer: %u", ifa->deadint);
   cli_msg(-1015, "\tRetransmit timer: %u", ifa->rxmtint);
   if ((ifa->type == OSPF_IT_BCAST) || (ifa->type == OSPF_IT_NBMA))
   {
@@ -828,9 +1149,3 @@ ospf_iface_info(struct ospf_iface *ifa)
   }
 }
 
-void
-ospf_iface_shutdown(struct ospf_iface *ifa)
-{
-  init_list(&ifa->neigh_list);
-  hello_timer_hook(ifa->hello_timer);
-}
diff --git a/proto/ospf/iface.h b/proto/ospf/iface.h
index f9631eb3..3f887728 100644
--- a/proto/ospf/iface.h
+++ b/proto/ospf/iface.h
@@ -16,10 +16,11 @@ struct ospf_iface *ospf_iface_find(struct proto_ospf *p, struct iface *what);
 void ospf_if_notify(struct proto *p, unsigned flags, struct iface *iface);
 void ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a);
 void ospf_iface_info(struct ospf_iface *ifa);
+void ospf_iface_new(struct ospf_area *oa, struct ifa *addr, struct ospf_iface_patt *ip);
+void ospf_iface_remove(struct ospf_iface *ifa);
 void ospf_iface_shutdown(struct ospf_iface *ifa);
-void ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr, struct ospf_area_config *ac, struct ospf_iface_patt *ip);
-void ospf_iface_change_mtu(struct proto_ospf *po, struct ospf_iface *ifa);
-void ospf_set_rxbuf_size(struct ospf_iface *ifa, u32 rxbuf);
+int ospf_iface_reconfigure(struct ospf_iface *ifa, struct ospf_iface_patt *new);
+void ospf_ifaces_reconfigure(struct ospf_area *oa, struct ospf_area_config *nac);
 
 struct nbma_node *find_nbma_node_in(list *nnl, ip_addr ip);
 
@@ -27,5 +28,4 @@ static inline struct nbma_node *
 find_nbma_node(struct ospf_iface *ifa, ip_addr ip)
 { return find_nbma_node_in(&ifa->nbma_list, ip); }
 
-
 #endif /* _BIRD_OSPF_IFACE_H_ */
diff --git a/proto/ospf/lsalib.c b/proto/ospf/lsalib.c
index 2f52fe9a..224c345e 100644
--- a/proto/ospf/lsalib.c
+++ b/proto/ospf/lsalib.c
@@ -23,6 +23,18 @@ flush_lsa(struct top_hash_entry *en, struct proto_ospf *po)
   ospf_hash_delete(po->gr, en);
 }
 
+void
+ospf_flush_area(struct proto_ospf *po, u32 areaid)
+{
+  struct top_hash_entry *en, *nxt;
+
+  WALK_SLIST_DELSAFE(en, nxt, po->lsal)
+  {
+    if ((LSA_SCOPE(&en->lsa) == LSA_SCOPE_AREA) && (en->domain == areaid))
+      flush_lsa(en, po);
+  }
+}
+
 /**
  * ospf_age
  * @po: ospf protocol
diff --git a/proto/ospf/lsalib.h b/proto/ospf/lsalib.h
index 8a949d86..0b556ec5 100644
--- a/proto/ospf/lsalib.h
+++ b/proto/ospf/lsalib.h
@@ -36,5 +36,7 @@ int lsa_validate(struct ospf_lsa_header *lsa, void *body);
 struct top_hash_entry * lsa_install_new(struct proto_ospf *po, struct ospf_lsa_header *lsa, u32 domain, void *body);
 void ospf_age(struct proto_ospf *po);
 void flush_lsa(struct top_hash_entry *en, struct proto_ospf *po);
+void ospf_flush_area(struct proto_ospf *po, u32 areaid);
+
 
 #endif /* _BIRD_OSPF_LSALIB_H_ */
diff --git a/proto/ospf/neighbor.c b/proto/ospf/neighbor.c
index 98c9de50..642365b3 100644
--- a/proto/ospf/neighbor.c
+++ b/proto/ospf/neighbor.c
@@ -349,7 +349,7 @@ ospf_neigh_sm(struct ospf_neighbor *n, int event)
     case NEIGHBOR_DOWN:
       neigh_chstate(n, NEIGHBOR_INIT);
     default:
-      tm_start(n->inactim, n->ifa->dead);	/* Restart inactivity timer */
+      tm_start(n->inactim, n->ifa->deadint);	/* Restart inactivity timer */
       break;
     }
     break;
@@ -548,16 +548,6 @@ find_neigh_by_ip(struct ospf_iface *ifa, ip_addr ip)
   return NULL;
 }
 
-struct ospf_area *
-ospf_find_area(struct proto_ospf *po, u32 aid)
-{
-  struct ospf_area *oa;
-  WALK_LIST(oa, po->area_list)
-    if (((struct ospf_area *) oa)->areaid == aid)
-      return oa;
-  return NULL;
-}
-
 /* Neighbor is inactive for a long time. Remove it. */
 static void
 neighbor_timer_hook(timer * timer)
diff --git a/proto/ospf/neighbor.h b/proto/ospf/neighbor.h
index dcaa12df..f593faed 100644
--- a/proto/ospf/neighbor.h
+++ b/proto/ospf/neighbor.h
@@ -15,7 +15,6 @@ void ospf_neigh_sm(struct ospf_neighbor *n, int event);
 void bdr_election(struct ospf_iface *ifa);
 struct ospf_neighbor *find_neigh(struct ospf_iface *ifa, u32 rid);
 struct ospf_neighbor *find_neigh_by_ip(struct ospf_iface *ifa, ip_addr ip);
-struct ospf_area *ospf_find_area(struct proto_ospf *po, u32 aid);
 void ospf_neigh_remove(struct ospf_neighbor *n);
 void ospf_sh_neigh_info(struct ospf_neighbor *n);
 
diff --git a/proto/ospf/ospf.c b/proto/ospf/ospf.c
index e10a405c..ce913f7b 100644
--- a/proto/ospf/ospf.c
+++ b/proto/ospf/ospf.c
@@ -122,27 +122,95 @@ static void
 add_area_nets(struct ospf_area *oa, struct ospf_area_config *ac)
 {
     struct proto_ospf *po = oa->po;
-    struct proto *p = &po->proto;
-    struct area_net_config *anet;
-    struct area_net *antmp;
+    struct area_net_config *anc;
+    struct area_net *an;
 
-    fib_init(&oa->net_fib, p->pool, sizeof(struct area_net), 0, ospf_area_initfib);
+    fib_init(&oa->net_fib, po->proto.pool, sizeof(struct area_net), 0, ospf_area_initfib);
 
-    WALK_LIST(anet, ac->net_list)
+    WALK_LIST(anc, ac->net_list)
     {
-      antmp = (struct area_net *) fib_get(&oa->net_fib, &anet->px.addr, anet->px.len);
-      antmp->hidden = anet->hidden;
+      an = (struct area_net *) fib_get(&oa->net_fib, &anc->px.addr, anc->px.len);
+      an->hidden = an->hidden;
     }
 }
 
+static void
+ospf_area_add(struct proto_ospf *po, struct ospf_area_config *ac, int reconf)
+{
+  struct proto *p = &po->proto;
+  struct ospf_area *oa;
+
+  OSPF_TRACE(D_EVENTS, "Adding area %R", ac->areaid);
+
+  oa = mb_allocz(p->pool, sizeof(struct ospf_area));
+  add_tail(&po->area_list, NODE oa);
+  po->areano++;
+
+  oa->ac = ac;
+  oa->stub = ac->stub;
+  oa->areaid = ac->areaid;
+  oa->rt = NULL;
+  oa->po = po;
+  fib_init(&oa->rtr, p->pool, sizeof(ort), 0, ospf_rt_initort);
+  add_area_nets(oa, ac);
+
+  if (oa->areaid == 0)
+    po->backbone = oa;
+
+#ifdef OSPFv2
+  oa->options = (oa->stub ? 0 : OPT_E);
+#else /* OSPFv3 */
+  oa->options = OPT_R | (oa->stub ? 0 : OPT_E) | OPT_V6;
+#endif
+
+  if (reconf)
+    ospf_ifaces_reconfigure(oa, ac);
+}
+
+static void
+ospf_area_remove(struct ospf_area *oa)
+{
+  struct proto *p = &oa->po->proto;
+  OSPF_TRACE(D_EVENTS, "Removing area %R", oa->areaid);
+
+  /* We suppose that interfaces are already removed */
+  ospf_flush_area(oa->po, oa->areaid);
+ 
+  fib_free(&oa->rtr);
+  fib_free(&oa->net_fib);
+
+  oa->po->areano--;
+  rem_node(NODE oa);
+  mb_free(oa);
+}
+
+
+struct ospf_area *
+ospf_find_area(struct proto_ospf *po, u32 aid)
+{
+  struct ospf_area *oa;
+  WALK_LIST(oa, po->area_list)
+    if (((struct ospf_area *) oa)->areaid == aid)
+      return oa;
+  return NULL;
+}
+
+static struct ospf_iface *
+ospf_find_vlink(struct proto_ospf *po, u32 voa, u32 vid)
+{
+  struct ospf_iface *ifa;
+  WALK_LIST(ifa, po->iface_list) 
+    if ((ifa->type == OSPF_IT_VLINK) && (ifa->voa->areaid == voa) && (ifa->vid == vid))
+      return ifa;
+  return NULL;
+}
+
 static int
 ospf_start(struct proto *p)
 {
   struct proto_ospf *po = (struct proto_ospf *) p;
   struct ospf_config *c = (struct ospf_config *) (p->cf);
   struct ospf_area_config *ac;
-  struct ospf_area *oa;
-  int vlinks = 0;
 
   po->router_id = proto_get_router_id(p->cf);
   po->rfc1583 = c->rfc1583;
@@ -165,68 +233,14 @@ ospf_start(struct proto *p)
   po->areano = 0;
   po->gr = ospf_top_new(p->pool);
   s_init_list(&(po->lsal));
-  if (EMPTY_LIST(c->area_list))
-  {
-    log(L_ERR "Cannot start, no OSPF areas configured!");
-    return PS_DOWN;
-  }
 
   WALK_LIST(ac, c->area_list)
-  {
-    oa = mb_allocz(p->pool, sizeof(struct ospf_area));
-    add_tail(&po->area_list, NODE oa);
-    po->areano++;
-    oa->ac = ac;
-    oa->stub = ac->stub;
-    oa->areaid = ac->areaid;
-    oa->rt = NULL;
-    oa->po = po;
-    add_area_nets(oa, ac);
-    fib_init(&oa->rtr, p->pool, sizeof(ort), 0, ospf_rt_initort);
-
-    if (oa->areaid == 0)
-    {
-      po->backbone = oa;
-      if (oa->stub) log(L_ERR "Backbone cannot be stub. Ignoring!");
-      oa->stub = 0;
-    }
+    ospf_area_add(po, ac, 0);
 
-    if (!EMPTY_LIST(ac->vlink_list))
-      vlinks = 1;
-
-#ifdef OSPFv2
-    oa->options = (oa->stub ? 0 : OPT_E);
-#else /* OSPFv3 */
-    oa->options = OPT_R | (oa->stub ? 0 : OPT_E) | OPT_V6;
-#endif
-  }
-
-  /* ABR is always in the backbone */
-  if (((po->areano > 1) || vlinks) && !po->backbone)
-  {
-    oa = mb_allocz(p->pool, sizeof(struct ospf_area));
-    add_tail(&po->area_list, NODE oa);
-    po->areano++;
-    oa->ac = NULL;
-    oa->stub = 0;
-    oa->areaid = 0;
-    oa->rt = NULL;
-    oa->po = po;
-    fib_init(&oa->net_fib, p->pool, sizeof(struct area_net), 0, ospf_area_initfib);
-    fib_init(&oa->rtr, p->pool, sizeof(ort), 0, ospf_rt_initort);
-    po->backbone = oa;
-#ifdef OSPFv2
-    oa->options = OPT_E;
-#else /* OSPFv3 */
-    oa->options = OPT_R | OPT_E | OPT_V6;
-#endif
-  }
-
-  /* Add all virtual links as interfaces */
-  struct ospf_iface_patt *ipatt;
-  WALK_LIST(ac, c->area_list)
-    WALK_LIST(ipatt, ac->vlink_list)
-    ospf_iface_new(po, NULL, NULL, ac, ipatt);
+  /* Add all virtual links */
+  struct ospf_iface_patt *ic;
+  WALK_LIST(ic, c->vlink_list)
+    ospf_iface_new(po->backbone, NULL, ic);
 
   return PS_UP;
 }
@@ -513,8 +527,7 @@ ospf_shutdown(struct proto *p)
 
   /* And send to all my neighbors 1WAY */
   WALK_LIST(ifa, po->iface_list)
-    if (ifa->state > OSPF_IS_DOWN)
-      ospf_iface_shutdown(ifa);
+    ospf_iface_shutdown(ifa);
 
   /* Cleanup locked rta entries */
   FIB_WALK(&po->rtf, nftmp)
@@ -622,10 +635,22 @@ ospf_get_attr(eattr * a, byte * buf, int buflen UNUSED)
   }
 }
 
-static int
-ospf_patt_compare(struct ospf_iface_patt *a, struct ospf_iface_patt *b)
+static void
+ospf_area_reconfigure(struct ospf_area *oa, struct ospf_area_config *nac)
 {
-  return (a->type == b->type);
+  oa->ac = nac;
+  oa->stub = nac->stub;
+
+  ospf_ifaces_reconfigure(oa, nac);
+
+  /* Handle net_list */
+  fib_free(&oa->net_fib);
+  add_area_nets(oa, nac);
+
+  /* No need to handle stubnet_list */
+
+  oa->marked = 0;
+  schedule_rt_lsa(oa);
 }
 
 /**
@@ -641,296 +666,70 @@ ospf_patt_compare(struct ospf_iface_patt *a, struct ospf_iface_patt *b)
 static int
 ospf_reconfigure(struct proto *p, struct proto_config *c)
 {
+  struct proto_ospf *po = (struct proto_ospf *) p;
   struct ospf_config *old = (struct ospf_config *) (p->cf);
   struct ospf_config *new = (struct ospf_config *) c;
-  struct ospf_area_config *oldac, *newac;
-  struct proto_ospf *po = (struct proto_ospf *) p;
-  struct ospf_iface_patt *oldip, *newip;
-  struct ospf_iface *ifa;
-  struct nbma_node *nb1, *nb2, *nbnx;
-  struct ospf_area *oa = NULL;
-  int olddead, newdead;
-  
+  struct ospf_area_config *nac;
+  struct ospf_area *oa, *oax;
+  struct ospf_iface *ifa, *ifx;
+  struct ospf_iface_patt *ip;
+
   if (po->rfc1583 != new->rfc1583)
     return 0;
 
-  schedule_rtcalc(po);
+  if (old->abr != new->abr)
+    return 0;
 
-  po->tick = new->tick;
   po->ecmp = new->ecmp;
+  po->tick = new->tick;
   po->disp_timer->recurrent = po->tick;
   tm_start(po->disp_timer, 1);
 
-  oldac = HEAD(old->area_list);
-  newac = HEAD(new->area_list);
+  /* Mark all areas and ifaces */
+  WALK_LIST(oa, po->area_list)
+    oa->marked = 1;
 
-  /* I should get it in the same order */
+  WALK_LIST(ifa, po->iface_list)
+    ifa->marked = 1;
 
-  while (((NODE(oldac))->next != NULL) && ((NODE(newac))->next != NULL))
+  /* Add and update areas */
+  WALK_LIST(nac, new->area_list)
   {
-    if (oldac->areaid != newac->areaid)
-      return 0;
-
-    WALK_LIST(oa, po->area_list)
-      if (oa->areaid == newac->areaid)
-        break;
-
-    if (!oa)
-      return 0;
-
-    oa->ac = newac;
-    oa->stub = newac->stub;
-    if (newac->stub && (oa->areaid == 0)) oa->stub = 0;
-
-    /* Check stubnet_list */
-    struct ospf_stubnet_config *oldsn = HEAD(oldac->stubnet_list);
-    struct ospf_stubnet_config *newsn = HEAD(newac->stubnet_list);
-
-    while (((NODE(oldsn))->next != NULL) && ((NODE(newsn))->next != NULL))
-      {
-	if (!ipa_equal(oldsn->px.addr, newsn->px.addr) ||
-	    (oldsn->px.len != newsn->px.len) ||
-	    (oldsn->hidden != newsn->hidden) ||
-	    (oldsn->summary != newsn->summary) ||
-	    (oldsn->cost != newsn->cost))
-	  break;
-
-	oldsn = (struct ospf_stubnet_config *)(NODE(oldsn))->next;
-	newsn = (struct ospf_stubnet_config *)(NODE(newsn))->next;
-      }
-
-    /* If there is no change, both pointers should be NULL */
-    if (((NODE(oldsn))->next) != ((NODE(newsn))->next))
-      schedule_rt_lsa(oa);
-
-    /* Change net_list */
-    fib_free(&oa->net_fib);
-    add_area_nets(oa, newac);
+    oa = ospf_find_area(po, nac->areaid);
+    if (oa)
+      ospf_area_reconfigure(oa, nac);
+    else
+      ospf_area_add(po, nac, 1);
+  }
 
-    if (!iface_patts_equal(&oldac->patt_list, &newac->patt_list,
-			   (void *) ospf_patt_compare))
-      return 0;
+  /* Add and update vlinks */
+  WALK_LIST(ip, new->vlink_list)
+  {
+    ifa = ospf_find_vlink(po, ip->voa, ip->vid);
+    if (ifa)
+      ospf_iface_reconfigure(ifa, ip);
+    else
+      ospf_iface_new(po->backbone, NULL, ip);
+  }
 
-    WALK_LIST(ifa, po->iface_list)
+  /* Delete remaining ifaces and areas */
+  WALK_LIST_DELSAFE(ifa, ifx, po->iface_list)
+    if (ifa->marked)
     {
-      /* FIXME: better handling of vlinks */
-      if (ifa->iface == NULL)
-        continue;
-
-      /* FIXME: better matching of interface_id in OSPFv3 */
-      if (oldip = (struct ospf_iface_patt *)
-	  iface_patt_find(&oldac->patt_list, ifa->iface, ifa->addr))
-      {
-	/* Now reconfigure interface */
-	if (!(newip = (struct ospf_iface_patt *)
-	      iface_patt_find(&newac->patt_list, ifa->iface, ifa->addr)))
-	  return 0;
-
-	/* HELLO TIMER */
-	if (oldip->helloint != newip->helloint)
-	{
-	  ifa->helloint = newip->helloint;
-	  ifa->hello_timer->recurrent = ifa->helloint;
-	  tm_start(ifa->hello_timer, ifa->helloint);
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing hello interval on interface %s from %d to %d",
-		     ifa->iface->name, oldip->helloint, newip->helloint);
-	}
-
-	/* POLL TIMER */
-	if ((oldip->pollint != newip->pollint) && ifa->poll_timer)
-	{
-	  ifa->pollint = newip->helloint;
-	  ifa->poll_timer->recurrent = ifa->pollint;
-	  tm_start(ifa->poll_timer, ifa->pollint);
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing poll interval on interface %s from %d to %d",
-		     ifa->iface->name, oldip->pollint, newip->pollint);
-	}
-
-	/* COST */
-	if (oldip->cost != newip->cost)
-	{
-	  ifa->cost = newip->cost;
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing cost interface %s from %d to %d",
-		     ifa->iface->name, oldip->cost, newip->cost);
-	  schedule_rt_lsa(ifa->oa);
-	}
-
-	/* RX BUFF */
-	if (oldip->rxbuf != newip->rxbuf)
-	{
-	  ifa->rxbuf = newip->rxbuf;
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing rxbuf interface %s from %d to %d",
-		     ifa->iface->name, oldip->rxbuf, newip->rxbuf);
-	  ospf_iface_change_mtu(po, ifa);
-	}
-
-	/* LINK */
-	if (oldip->check_link != newip->check_link)
-	{
-	  ifa->check_link = newip->check_link;
-
-	  if (!(ifa->iface->flags & IF_LINK_UP))
-	    ospf_iface_sm(ifa, ifa->check_link ? ISM_LOOP : ISM_UNLOOP);
-	}
-
-	/* ECMP weight */
-	if (oldip->ecmp_weight != newip->ecmp_weight)
-	{
-	  ifa->ecmp_weight = newip->ecmp_weight;
-	  OSPF_TRACE(D_EVENTS, "Changing ECMP weight of interface %s from %d to %d",
-		     ifa->iface->name, (int)oldip->ecmp_weight + 1, (int)newip->ecmp_weight + 1);
-	}
-
-	/* strict nbma */
-	if ((oldip->strictnbma == 0) && (newip->strictnbma != 0))
-	{
-	  ifa->strictnbma = newip->strictnbma;
-	  OSPF_TRACE(D_EVENTS,
-		     "Interface %s is now strict NBMA.", ifa->iface->name);
-	}
-	if ((oldip->strictnbma != 0) && (newip->strictnbma == 0))
-	{
-	  ifa->strictnbma = newip->strictnbma;
-	  OSPF_TRACE(D_EVENTS,
-		     "Interface %s is no longer strict NBMA.",
-		     ifa->iface->name);
-	}
-
-	/* stub */
-	int old_stub = ospf_iface_stubby(oldip, ifa->addr);
-	int new_stub = ospf_iface_stubby(newip, ifa->addr);
-	if (!old_stub && new_stub)
-	{
-	  ifa->stub = 1;
-	  OSPF_TRACE(D_EVENTS, "Interface %s is now stub.", ifa->iface->name);
-	}
-	if (old_stub && !new_stub && (ifa->ioprob == OSPF_I_OK))
-	{
-	  ifa->stub = 0;
-	  OSPF_TRACE(D_EVENTS, "Interface %s is no longer stub.", ifa->iface->name);
-	}
-
-#ifdef OSPFv2	
-	/* AUTHENTICATION */
-	if (oldip->autype != newip->autype)
-	{
-	  ifa->autype = newip->autype;
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing authentication type on interface %s",
-		     ifa->iface->name);
-	}
-        /* Add *passwords */
-	ifa->passwords = newip->passwords;
-#endif
-
-	/* priority */
-	if (oldip->priority != newip->priority)
-	{
-	  ifa->priority = newip->priority;
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing priority on interface %s from %d to %d",
-		     ifa->iface->name, oldip->priority, newip->priority);
-	}
-
-	/* RXMT */
-	if (oldip->rxmtint != newip->rxmtint)
-	{
-	  ifa->rxmtint = newip->rxmtint;
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing retransmit interval on interface %s from %d to %d",
-		     ifa->iface->name, oldip->rxmtint, newip->rxmtint);
-	}
-
-	/* WAIT */
-	if ((oldip->waitint != newip->waitint) && ifa->wait_timer)
-	{
-	  ifa->waitint = newip->waitint;
-	  if (ifa->wait_timer->expires != 0)
-	    tm_start(ifa->wait_timer, ifa->waitint);
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing wait interval on interface %s from %d to %d",
-		     ifa->iface->name, oldip->waitint, newip->waitint);
-	}
-
-	/* INFTRANS */
-	if (oldip->inftransdelay != newip->inftransdelay)
-	{
-	  ifa->inftransdelay = newip->inftransdelay;
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing transmit delay on interface %s from %d to %d",
-		     ifa->iface->name, oldip->inftransdelay,
-		     newip->inftransdelay);
-	}
-
-	/* DEAD */
-	olddead = (oldip->dead == 0) ? oldip->deadc * oldip->helloint : oldip->dead;
-	newdead = (newip->dead == 0) ? newip->deadc * newip->helloint : newip->dead;
-	if (olddead != newdead)
-	{
-	  ifa->dead = newdead;
-	  OSPF_TRACE(D_EVENTS,
-		     "Changing dead interval on interface %s from %d to %d",
-		     ifa->iface->name, olddead, newdead);
-	}
-
-	/* NBMA LIST */
-	/* First remove old */
-	WALK_LIST_DELSAFE(nb1, nbnx, ifa->nbma_list)
-	{
-	  nb2 = find_nbma_node_in(&newip->nbma_list, nb1->ip);
-	  if (nb2)
-	  {
-	    if (nb1->eligible != nb2->eligible)
-	    {
-	      nb1->eligible = nb2->eligible;
-	      OSPF_TRACE(D_EVENTS, "Changing neighbor eligibility %I on interface %s",
-			 nb1->ip, ifa->iface->name);
-	    }
-	  }
-	  else
-	  {
-	    OSPF_TRACE(D_EVENTS,
-		       "Removing NBMA neighbor %I on interface %s",
-		       nb1->ip, ifa->iface->name);
-	    rem_node(NODE nb1);
-	    mb_free(nb1);
-	  }
-	}
-	/* And then add new */
-	WALK_LIST(nb2, newip->nbma_list)
-	{
-	  if (!ipa_in_net(nb2->ip, ifa->addr->prefix, ifa->addr->pxlen))
-	    continue;
-
-	  if (find_nbma_node(ifa, nb2->ip) == NULL)
-	  {
-	    nb1 = mb_alloc(ifa->pool, sizeof(struct nbma_node));
-	    nb1->ip = nb2->ip;
-	    nb1->eligible = nb2->eligible;
-	    nb1->found = !!find_neigh_by_ip(ifa, nb1->ip);
-	    add_tail(&ifa->nbma_list, NODE nb1);
-	    OSPF_TRACE(D_EVENTS,
-		       "Adding NBMA neighbor %I on interface %s",
-		       nb1->ip, ifa->iface->name);
-	  }
-	}
-      }
+      ospf_iface_shutdown(ifa);
+      ospf_iface_remove(ifa);
     }
 
-    oldac = (struct ospf_area_config *)(NODE(oldac))->next;
-    newac = (struct ospf_area_config *)(NODE(newac))->next;
-  }
-
-  if (((NODE(oldac))->next) != ((NODE(newac))->next))
-    return 0;			/* One is not null */
+  WALK_LIST_DELSAFE(oa, oax, po->area_list)
+    if (oa->marked)
+      ospf_area_remove(oa);
 
-  return 1;			/* Everything OK :-) */
+  schedule_rtcalc(po);
+  
+  return 1;
 }
 
+
 void
 ospf_sh_neigh(struct proto *p, char *iff)
 {
diff --git a/proto/ospf/ospf.h b/proto/ospf/ospf.h
index 75ffb6de..74a8e316 100644
--- a/proto/ospf/ospf.h
+++ b/proto/ospf/ospf.h
@@ -81,9 +81,11 @@ struct ospf_config
 {
   struct proto_config c;
   unsigned tick;
-  int rfc1583;
+  byte rfc1583;
+  byte abr;
   int ecmp;
   list area_list;
+  list vlink_list;
 };
 
 struct nbma_node
@@ -121,11 +123,10 @@ struct ospf_area_config
 {
   node n;
   u32 areaid;
-  int stub;
+  u32 stub;
   list patt_list;
-  list vlink_list;
-  list net_list;
-  list stubnet_list;
+  list net_list;	      	/* List of aggregate networks for that area */
+  list stubnet_list;		/* List of stub networks added to Router LSA */
 };
 
 
@@ -167,6 +168,7 @@ struct ospf_iface
   struct iface *iface;		/* Nest's iface */
   struct ifa *addr;		/* IP prefix associated with that OSPF iface */
   struct ospf_area *oa;
+  struct ospf_iface_patt *cf;
   pool *pool;
   sock *sk;			/* IP socket (for DD ...) */
   list neigh_list;		/* List of neigbours */
@@ -174,7 +176,7 @@ struct ospf_iface
   u32 waitint;			/* number of sec before changing state from wait */
   u32 rxmtint;			/* number of seconds between LSA retransmissions */
   u32 pollint;			/* Poll interval */
-  u32 dead;			/* after "deadint" missing hellos is router dead */
+  u32 deadint;			/* after "deadint" missing hellos is router dead */
   u32 vid;			/* Id of peer of virtual link */
   ip_addr vip;			/* IP of peer of virtual link */
   struct ospf_iface *vifa;	/* OSPF iface which the vlink goes through */
@@ -252,8 +254,8 @@ struct ospf_iface
 #define OSPF_I_OK 0		/* Everything OK */
 #define OSPF_I_SK 1		/* Socket open failed */
 #define OSPF_I_LL 2		/* Missing link-local address (OSPFv3) */
-  // u8 sk_spf;			/* Socket is a member of SPFRouters group */
   u8 sk_dr; 			/* Socket is a member of DRouters group */
+  u8 marked;			/* Used in OSPF reconfigure */
   u16 rxbuf;			/* Buffer size */
   u8 check_link;		/* Whether iface link change is used */
   u8 ecmp_weight;		/* Weight used for ECMP */
@@ -715,14 +717,15 @@ struct ospf_area
   node n;
   u32 areaid;
   struct ospf_area_config *ac;	/* Related area config, might be NULL */
-  int origrt;			/* Rt lsa origination scheduled? */
   struct top_hash_entry *rt;	/* My own router LSA */
   struct top_hash_entry *pxr_lsa; /* Originated prefix LSA */
   list cand;			/* List of candidates for RT calc. */
   struct fib net_fib;		/* Networks to advertise or not */
-  unsigned stub;
-  int trcap;			/* Transit capability? */
+  u32 stub;			/* 0 or stub area cost */
   u32 options;			/* Optional features */
+  byte origrt;			/* Rt lsa origination scheduled? */
+  byte trcap;			/* Transit capability? */
+  byte marked;			/* Used in OSPF reconfigure */
   struct proto_ospf *po;
   struct fib rtr;		/* Routing tables for routers */
 };
@@ -753,18 +756,20 @@ struct proto_ospf
 struct ospf_iface_patt
 {
   struct iface_patt i;
+  u32 type;
+  u32 stub;
   u32 cost;
   u32 helloint;
   u32 rxmtint;
   u32 pollint;
-  u32 inftransdelay;
-  u32 priority;
   u32 waitint;
   u32 deadc;
-  u32 dead;
-  u32 type;
+  u32 deadint;
+  u32 inftransdelay;
+  u32 priority;
   u32 strictnbma;
-  u32 stub;
+  list nbma_list;
+  u32 voa;
   u32 vid;
   u16 rxbuf;
   u8 check_link;
@@ -772,9 +777,7 @@ struct ospf_iface_patt
 #define OSPF_RXBUF_NORMAL 0
 #define OSPF_RXBUF_LARGE 1
 #define OSPF_RXBUF_MINSIZE 256	/* Minimal allowed size */
-  list nbma_list;
-
-  u32 autype;			  /* Not really used in OSPFv3 */
+  u32 autype;			/* Not really used in OSPFv3 */
 #define OSPF_AUTH_NONE 0
 #define OSPF_AUTH_SIMPLE 1
 #define OSPF_AUTH_CRYPT 2
@@ -789,24 +792,6 @@ struct ospf_iface_patt
 #endif
 };
 
-#if defined(OSPFv2) && !defined(CONFIG_MC_PROPER_SRC)
-static inline int
-ospf_iface_stubby(struct ospf_iface_patt *ip, struct ifa *addr)
-{
-  /*
-   * We cannot properly support multiple OSPF ifaces on real iface
-   * with multiple prefixes, therefore we force OSPF ifaces with
-   * non-primary IP prefixes to be stub.
-   */
-  return ip->stub || !(addr->flags & IA_PRIMARY);
-}
-#else
-static inline int
-ospf_iface_stubby(struct ospf_iface_patt *ip, struct ifa *addr UNUSED)
-{
-  return ip->stub;
-}
-#endif
 
 int ospf_import_control(struct proto *p, rte **new, ea_list **attrs,
 			struct linpool *pool);
@@ -816,6 +801,8 @@ void schedule_rt_lsa(struct ospf_area *oa);
 void schedule_rtcalc(struct proto_ospf *po);
 void schedule_net_lsa(struct ospf_iface *ifa);
 
+struct ospf_area *ospf_find_area(struct proto_ospf *po, u32 aid);
+
 #ifdef OSPFv3
 void schedule_link_lsa(struct ospf_iface *ifa);
 #else
diff --git a/proto/ospf/topology.c b/proto/ospf/topology.c
index 9e693e13..1403e72e 100644
--- a/proto/ospf/topology.c
+++ b/proto/ospf/topology.c
@@ -1176,6 +1176,7 @@ static void *
 originate_prefix_rt_lsa_body(struct ospf_area *oa, u16 *length)
 {
   struct proto_ospf *po = oa->po;
+  struct ospf_config *cf = (struct ospf_config *) (po->proto.cf);
   struct ospf_iface *ifa;
   struct ospf_lsa_prefix *lp;
   struct ifa *vlink_addr = NULL;
@@ -1234,7 +1235,7 @@ originate_prefix_rt_lsa_body(struct ospf_area *oa, u16 *length)
 
   /* If there are some configured vlinks, add some global address,
      which will be used as a vlink endpoint. */
-  if (oa->ac && !EMPTY_LIST(oa->ac->vlink_list) && !host_addr && vlink_addr)
+  if (!EMPTY_LIST(cf->vlink_list) && !host_addr && vlink_addr)
   {
     lsa_put_prefix(po, vlink_addr->ip, MAX_PREFIX_LENGTH, 0);
     i++;