Fixes several problems in OSPF vlink implementation.

proto/ospf/config.Y

@@ -164,7 +164,6 @@ ospf_vlink_start: VIRTUAL LINK idval
   add_tail(&this_area->vlink_list, NODE this_ipatt);
   init_list(&this_ipatt->ipn_list);
   OSPF_PATT->vid = $3;
-  OSPF_PATT->cost = COST_D;
   OSPF_PATT->helloint = HELLOINT_D;
   OSPF_PATT->rxmtint = RXMTINT_D;
   OSPF_PATT->inftransdelay = INFTRANSDELAY_D;

proto/ospf/iface.c

@@ -260,6 +260,7 @@ ospf_iface_down(struct ospf_iface *ifa)
     ifa->iface = NULL;
     ifa->addr = NULL;
     ifa->sk = NULL;
+    ifa->cost = 0;
     ifa->vip = IPA_NONE;
     return;
   }
@@ -445,27 +446,6 @@ ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr,
 
 #ifdef OSPFv3
   ifa->instance_id = ip->instance_id;
-
-  /*
-  addr = NULL;
-  if (ifa->type != OSPF_IT_VLINK)
-    {
-      struct ifa *a;
-      WALK_LIST(a, iface->addrs)
-	if (a->scope == SCOPE_LINK)
-	  {
-	    addr = a;
-	    break;
-	  }
-
-      if (!addr)
-      {
-	log(L_ERR "%s: Missing link-local address on interface %s, declaring as stub", p->name,  iface->name);
-	ifa->ioprob = OSPF_I_LL;
-	ifa->stub = 1;
-      }
-    }
-  */
 #endif
 
   if (ip->type == OSPF_IT_UNDEF)

proto/ospf/rt.h

@@ -18,21 +18,30 @@ typedef struct orta
 {
   int type;
   u32 options;
-  /* router-LSA style options (for ORT_ROUTER), with V,E,B bits.
+  /*
-     In OSPFv2, ASBRs from another areas (that we know from rt-summary-lsa),
+   * For ORT_ROUTER routes, options field are router-LSA style
-     have just ORTA_ASBR in options, their real options are unknown */
+   * options, with V,E,B bits. In OSPFv2, ASBRs from another areas
+   * (that we know from rt-summary-lsa) have just ORTA_ASBR in
+   * options, their real options are unknown.
+   */
 #define ORTA_ASBR OPT_RT_E
 #define ORTA_ABR  OPT_RT_B
-  struct ospf_area *oa;
+  /*
+   * For ORT_NET routes, the field is almost unused with one
+   * exception: ORTA_PREF for external routes means that the route is
+   * preferred in AS external route selection according to 16.4.1. -
+   * it is intra-area path using non-backbone area. In other words,
+   * the forwarding address (or ASBR if forwarding address is zero) is
+   * intra-area (type == RTS_OSPF) and its area is not a backbone.
+   */
+#define ORTA_PREF 0x80000000
   u32 metric1;
   u32 metric2;
-  ip_addr nh;			/* Next hop */
-  struct ospf_iface *ifa;	/* Outgoing interface */
-  struct top_hash_entry *ar;	/* Advertising router (or ABR) */
   u32 tag;
   u32 rid;			/* Router ID of real advertising router */
-  /* For ext-LSA from different area, 'ar' is a type 1 LSA of ABR.
+  struct ospf_area *oa;
-     Router ID of real advertising router is stored in 'rid'. */
+  struct ospf_iface *ifa;	/* Outgoing interface */
+  ip_addr nh;			/* Next hop */
 }
 orta;
 
@@ -41,7 +50,6 @@ typedef struct ort
   struct fib_node fn;
   orta n;
   orta o;
-  struct ort *efn;		/* For RFC1583 */
 }
 ort;
 

proto/ospf/topology.c

@@ -1114,6 +1114,8 @@ originate_prefix_rt_lsa_body(struct ospf_area *oa, u16 *length)
   struct proto_ospf *po = oa->po;
   struct ospf_iface *ifa;
   struct ospf_lsa_prefix *lp;
+  struct ifa *vlink_addr = NULL;
+  int host_addr = 0;
   int net_lsa;
   int i = 0;
   u8 flags;
@@ -1139,10 +1141,15 @@ originate_prefix_rt_lsa_body(struct ospf_area *oa, u16 *length)
     struct ifa *a;
     WALK_LIST(a, ifa->iface->addrs)
       {
-	if (((a->pxlen < MAX_PREFIX_LENGTH) && net_lsa) ||
+	if ((a->flags & IA_SECONDARY) ||
-	    (a->flags & IA_SECONDARY) ||
 	    (a->flags & IA_UNNUMBERED) ||
-	    (a->scope <= SCOPE_LINK) ||
+	    (a->scope <= SCOPE_LINK))
+	  continue;
+
+	if (!vlink_addr)
+	  vlink_addr = a;
+
+	if (((a->pxlen < MAX_PREFIX_LENGTH) && net_lsa) ||
 	    configured_stubnet(oa, a))
 	  continue;
 
@@ -1150,10 +1157,20 @@ originate_prefix_rt_lsa_body(struct ospf_area *oa, u16 *length)
 	put_ipv6_prefix(lsab_alloc(po, IPV6_PREFIX_SPACE(a->pxlen)),
 			a->ip, a->pxlen, flags, ifa->cost);
 	i++;
+
+	if (flags & OPT_PX_LA)
+	  host_addr = 1;
       }
   }
 
-  /* FIXME Handle vlinks? see RFC5340, page 38 */
+  /* If there are some configured vlinks, add some global address,
+     which will be used as a vlink endpoint. */
+  if (!EMPTY_LIST(oa->ac->vlink_list) && !host_addr && vlink_addr)
+  {
+    put_ipv6_prefix(lsab_alloc(po, IPV6_PREFIX_SPACE(MAX_PREFIX_LENGTH)),
+		    vlink_addr->ip, MAX_PREFIX_LENGTH, OPT_PX_LA, 0);
+    i++;
+  }
 
   struct ospf_stubnet_config *sn;
   WALK_LIST(sn, oa->ac->stubnet_list)
@@ -1227,6 +1244,7 @@ prefix_advance(u32 *buf)
   return buf + IPV6_PREFIX_WORDS(pxl);
 }
 
+/* FIXME eliminate items wit LA bit set? see 4.4.3.9 */
 static void
 add_prefix(struct proto_ospf *po, u32 *px, int offset, int *pxc)
 {

proto/ospf/topology.h

@@ -21,7 +21,7 @@ struct top_hash_entry
   void *lsa_body;
   bird_clock_t inst_t;		/* Time of installation into DB */
   ip_addr nh;			/* Next hop */
-  ip_addr lb;			/* Link back */
+  ip_addr lb;			/* In OSPFv2, link back address. In OSPFv3, any global address in the area useful for vlinks */
   struct ospf_iface *nhi;	/* Next hop interface */
 #ifdef OSPFv3
   u32 lb_id;			/* Interface ID of link back iface (for bcast or NBMA networks) */