zebra: use link scope for interface routes

In linux, 'scope' is a hint of distance of the IP. And this is
evident from the fact that only lower scope can be used as recursive
via lookup result. This changes all interface routes scope to link
so kernel will allow regular routes to use it as via. Then we do
not need to use the 'onlink' attribute.

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c
index 4625cea..6e22d63 100644
--- a/zebra/rt_netlink.c
+++ b/zebra/rt_netlink.c
@@ -1638,7 +1638,7 @@
   req.r.rtm_table = rib->table;
   req.r.rtm_dst_len = p->prefixlen;
   req.r.rtm_protocol = RTPROT_ZEBRA;
-  req.r.rtm_scope = RT_SCOPE_UNIVERSE;
+  req.r.rtm_scope = RT_SCOPE_LINK;
 
   if ((rib->flags & ZEBRA_FLAG_BLACKHOLE) || (rib->flags & ZEBRA_FLAG_REJECT))
     discard = 1;
@@ -1706,6 +1706,10 @@
       if (cmd == RTM_DELROUTE && !CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB))
         continue;
 
+      if (nexthop->type != NEXTHOP_TYPE_IFINDEX &&
+          nexthop->type != NEXTHOP_TYPE_IFNAME)
+        req.r.rtm_scope = RT_SCOPE_UNIVERSE;
+
       nexthop_num++;
     }
 
diff --git a/zebra/zebra_rib.c b/zebra/zebra_rib.c
index 7cce13f..9264087 100644
--- a/zebra/zebra_rib.c
+++ b/zebra/zebra_rib.c
@@ -439,26 +439,17 @@
 			  {
 			    resolved_hop->type = newhop->type;
 			    resolved_hop->gate.ipv4 = newhop->gate.ipv4;
-
-			    if (newhop->ifindex)
-			      {
-				resolved_hop->type = NEXTHOP_TYPE_IPV4_IFINDEX;
-				resolved_hop->ifindex = newhop->ifindex;
-			      }
+			    resolved_hop->ifindex = newhop->ifindex;
 			  }
 
-			/* If the resolving route is an interface route,
-			 * it means the gateway we are looking up is connected
-			 * to that interface. (The actual network is _not_ onlink).
-			 * Therefore, the resolved route should have the original
-			 * gateway as nexthop as it is directly connected.
-			 *
-			 * On Linux, we have to set the onlink netlink flag because
-			 * otherwise, the kernel won't accept the route. */
+			/* If the resolving route is an interface route, it
+			 * means the gateway we are looking up is connected
+			 * to that interface. Therefore, the resolved route
+			 * should have the original gateway as nexthop as it
+			 * is directly connected. */
 			if (newhop->type == NEXTHOP_TYPE_IFINDEX
 			    || newhop->type == NEXTHOP_TYPE_IFNAME)
 			  {
-			    resolved_hop->flags |= NEXTHOP_FLAG_ONLINK;
 			    resolved_hop->type = NEXTHOP_TYPE_IPV4_IFINDEX;
 			    resolved_hop->gate.ipv4 = nexthop->gate.ipv4;
 			    resolved_hop->ifindex = newhop->ifindex;