Many changes in (mainly) kernel syncers.

- BSD kernel syncer is now self-conscious and can learn alien routes
- important bugfix in BSD kernel syncer (crash after protocol restart)
- many minor changes and bugfixes in kernel syncers and neighbor cache
- direct protocol does not generate host and link local routes
- min_scope check is removed, all routes have SCOPE_UNIVERSE by default
- also fixes some remaining compiler warnings

nest/iface.h

@@ -97,6 +97,7 @@ typedef struct neighbor {
 } neighbor;
 
 #define NEF_STICKY 1
+#define NEF_ONLINK 2
 
 neighbor *neigh_find(struct proto *, ip_addr *, unsigned flags);
 neighbor *neigh_find2(struct proto *p, ip_addr *a, struct iface *ifa, unsigned flags);

nest/neighbor.c

@@ -112,12 +112,12 @@ neighbor *
 neigh_find2(struct proto *p, ip_addr *a, struct iface *ifa, unsigned flags)
 {
   neighbor *n;
-  int class, scope = SCOPE_HOST;
+  int class, scope = -1;       ;
   unsigned int h = neigh_hash(p, a);
   struct iface *i;
 
   WALK_LIST(n, neigh_hash_table[h])	/* Search the cache */
-    if (n->proto == p && ipa_equal(*a, n->addr))
+    if (n->proto == p && ipa_equal(*a, n->addr) && (!ifa || (ifa == n->iface)))
       return n;
 
   class = ipa_classify(*a);
@@ -129,7 +129,12 @@ neigh_find2(struct proto *p, ip_addr *a, struct iface *ifa, unsigned flags)
     return NULL;			/* Bad scope or a somecast */
 
   if (ifa)
-    scope = if_connected(a, ifa);
+    {
+      scope = if_connected(a, ifa);
+
+      if ((scope < 0) && (flags & NEF_ONLINK))
+	scope = class & IADDR_SCOPE_MASK;
+    }
   else
     WALK_LIST(i, iface_list)
       if ((scope = if_connected(a, i)) >= 0)
@@ -138,22 +143,28 @@ neigh_find2(struct proto *p, ip_addr *a, struct iface *ifa, unsigned flags)
 	  break;
 	}
 
-  if (!ifa && !(flags & NEF_STICKY))
+  /* scope < 0 means i don't know neighbor */
+  /* scope >= 0 implies ifa != NULL */
+
+  if ((scope < 0) && !(flags & NEF_STICKY))
     return NULL;
 
   n = sl_alloc(neigh_slab);
   n->addr = *a;
-  n->iface = ifa;
-  if (ifa)
+  if (scope >= 0)
     {
       add_tail(&neigh_hash_table[h], &n->n);
       add_tail(&ifa->neighbors, &n->if_n);
     }
   else
     {
+      /* sticky flag does not work for link-local neighbors;
+	 fortunately, we don't use this combination */
       add_tail(&sticky_neigh_list, &n->n);
+      ifa = NULL;
       scope = 0;
     }
+  n->iface = ifa;
   n->proto = p;
   n->data = NULL;
   n->aux = 0;

nest/proto.c

@@ -113,7 +113,6 @@ proto_new(struct proto_config *c, unsigned size)
   p->table = c->table->table;
   p->in_filter = c->in_filter;
   p->out_filter = c->out_filter;
-  p->min_scope = SCOPE_SITE;
   p->hash_key = random_u32();
   c->proto = p;
   return p;

nest/protocol.h

@@ -130,7 +130,6 @@ struct proto {
   u32 debug;				/* Debugging flags */
   u32 mrtdump;				/* MRTDump flags */
   unsigned preference;			/* Default route preference */
-  int min_scope;			/* Minimal route scope accepted */
   unsigned accept_ra_types;		/* Which types of route announcements are accepted (RA_OPTIMAL or RA_ANY) */
   unsigned disabled;			/* Manually disabled */
   unsigned proto_state;			/* Protocol state machine (see below) */

nest/rt-dev.c

@@ -33,6 +33,10 @@ dev_ifa_notify(struct proto *p, unsigned c, struct ifa *ad)
       !iface_patt_find(&P->iface_list, ad->iface))
     /* Empty list is automagically treated as "*" */
     return;
+
+  if (ad->scope <= SCOPE_LINK)
+    return;
+
   if (c & IF_CHANGE_DOWN)
     {
       net *n;
@@ -56,7 +60,7 @@ dev_ifa_notify(struct proto *p, unsigned c, struct ifa *ad)
       bzero(&A, sizeof(A));
       A.proto = p;
       A.source = RTS_DEVICE;
-      A.scope = ad->scope;
+      A.scope = SCOPE_UNIVERSE;
       A.cast = RTC_UNICAST;
       A.dest = RTD_DEVICE;
       A.iface = ad->iface;
@@ -76,7 +80,6 @@ dev_init(struct proto_config *c)
   struct proto *p = proto_new(c, sizeof(struct proto));
 
   p->ifa_notify = dev_ifa_notify;
-  p->min_scope = SCOPE_HOST;
   return p;
 }
 

nest/rt-table.c

@@ -158,7 +158,7 @@ rte_trace_out(unsigned int flag, struct proto *p, rte *e, char *msg)
 }
 
 static inline void
-do_rte_announce(struct announce_hook *a, int type UNUSED, net *net, rte *new, rte *old, ea_list *tmpa, int class, int refeed)
+do_rte_announce(struct announce_hook *a, int type UNUSED, net *net, rte *new, rte *old, ea_list *tmpa, int refeed)
 {
   struct proto *p = a->proto;
   struct filter *filter = p->out_filter;
@@ -183,13 +183,7 @@ do_rte_announce(struct announce_hook *a, int type UNUSED, net *net, rte *new, rt
       stats->exp_updates_received++;
 
       char *drop_reason = NULL;
-      if ((class & IADDR_SCOPE_MASK) < p->min_scope)
-	{
-	  stats->exp_updates_rejected++;
-	  drop_reason = "out of scope";
-	  fast_exit_hack = 1;
-	}
-      else if ((ok = p->import_control ? p->import_control(p, &new, &tmpa, rte_update_pool) : 0) < 0)
+      if ((ok = p->import_control ? p->import_control(p, &new, &tmpa, rte_update_pool) : 0) < 0)
 	{
 	  stats->exp_updates_rejected++;
 	  drop_reason = "rejected by protocol";
@@ -332,7 +326,6 @@ static void
 rte_announce(rtable *tab, unsigned type, net *net, rte *new, rte *old, ea_list *tmpa)
 {
   struct announce_hook *a;
-  int class = ipa_classify(net->n.prefix);
 
   if (type == RA_OPTIMAL)
     {
@@ -346,7 +339,7 @@ rte_announce(rtable *tab, unsigned type, net *net, rte *new, rte *old, ea_list *
     {
       ASSERT(a->proto->core_state == FS_HAPPY || a->proto->core_state == FS_FEEDING);
       if (a->proto->accept_ra_types == type)
-	do_rte_announce(a, type, net, new, old, tmpa, class, 0);
+	do_rte_announce(a, type, net, new, old, tmpa, 0);
     }
 }
 
@@ -362,33 +355,15 @@ rte_validate(rte *e)
 	  n->n.prefix, n->n.pxlen, e->sender->name);
       return 0;
     }
-  if (n->n.pxlen)
+
+  c = ipa_classify_net(n->n.prefix);
+  if ((c < 0) || !(c & IADDR_HOST) || ((c & IADDR_SCOPE_MASK) <= SCOPE_LINK))
     {
-      c = ipa_classify(n->n.prefix);
-      if (c < 0 || !(c & IADDR_HOST))
-	{
-	  if (!ipa_nonzero(n->n.prefix))
-	    {
-	      /* Various default routes */
-#ifdef IPV6
-	      if (n->n.pxlen == 96)
-#else
-	      if (n->n.pxlen <= 1)
-#endif
-		return 1;
-	    }
-	  log(L_WARN "Ignoring bogus route %I/%d received via %s",
-	      n->n.prefix, n->n.pxlen, e->sender->name);
-	  return 0;
-	}
-      if ((c & IADDR_SCOPE_MASK) < e->sender->min_scope)
-	{
-	  log(L_WARN "Ignoring %s scope route %I/%d received from %I via %s",
-	      ip_scope_text(c & IADDR_SCOPE_MASK),
-	      n->n.prefix, n->n.pxlen, e->attrs->from, e->sender->name);
-	  return 0;
-	}
+      log(L_WARN "Ignoring bogus route %I/%d received via %s",
+	  n->n.prefix, n->n.pxlen, e->sender->name);
+      return 0;
     }
+
   return 1;
 }
 
@@ -1018,7 +993,7 @@ do_feed_baby(struct proto *p, int type, struct announce_hook *h, net *n, rte *e)
 
   rte_update_lock();
   tmpa = q->make_tmp_attrs ? q->make_tmp_attrs(e, rte_update_pool) : NULL;
-  do_rte_announce(h, type, n, e, p->refeeding ? e : NULL, tmpa, ipa_classify(n->n.prefix), p->refeeding);
+  do_rte_announce(h, type, n, e, p->refeeding ? e : NULL, tmpa, p->refeeding);
   rte_update_unlock();
 }
 
@@ -1190,11 +1165,8 @@ rt_show_net(struct cli *c, net *n, struct rt_show_data *d)
       if (p2 && p2 != p0) ok = 0;
       if (ok && d->export_mode)
 	{
-	  int class = ipa_classify(n->n.prefix);
 	  int ic;
-	  if ((class & IADDR_SCOPE_MASK) < p1->min_scope)
-	    ok = 0;
-	  else if ((ic = p1->import_control ? p1->import_control(p1, &e, &tmpa, rte_update_pool) : 0) < 0)
+	  if ((ic = p1->import_control ? p1->import_control(p1, &e, &tmpa, rte_update_pool) : 0) < 0)
 	    ok = 0;
 	  else if (!ic && d->export_mode > 1)
 	    {