Route destination field merged with nexthop attribute; splitting flowspec validation result out.

As there is either a nexthop or another destination specification
(or othing in case of ROAs and Flowspec), it may be merged together.
This code is somehow quirky and should be replaced in future by better
implementation of nexthop.

Also flowspec validation result has its own attribute now as it doesn't
have anything to do with route nexthop.

1 files changed, 41 insertions, 37 deletions

diff --git a/sysdep/linux/netlink.c b/sysdep/linux/netlink.c
index fdfd4885..40f6212e 100644
--- a/sysdep/linux/netlink.c
+++ b/sysdep/linux/netlink.c
@@ -1407,11 +1407,16 @@ HASH_DEFINE_REHASH_FN(RTH, struct krt_proto)
 int
 krt_capable(rte *e)
 {
-  rta *a = e->attrs;
+  eattr *ea = ea_find(e->attrs->eattrs, &ea_gen_nexthop);
+  if (!ea)
+    return 0;
+
+  struct nexthop_adata *nhad = (void *) ea->u.ptr;
+  if (NEXTHOP_IS_REACHABLE(nhad))
+    return 1;
 
-  switch (a->dest)
+  switch (nhad->dest)
   {
-    case RTD_UNICAST:
     case RTD_BLACKHOLE:
     case RTD_UNREACHABLE:
     case RTD_PROHIBIT:
@@ -1591,7 +1596,7 @@ nl_add_rte(struct krt_proto *p, rte *e)
   eattr *nhea = ea_find(a->eattrs, &ea_gen_nexthop);
   struct nexthop_adata *nhad = nhea ? (struct nexthop_adata *) nhea->u.ptr : NULL;
 
-  if (krt_ecmp6(p) && nhad && !NEXTHOP_ONE(nhad))
+  if (krt_ecmp6(p) && nhad && NEXTHOP_IS_REACHABLE(nhad) && !NEXTHOP_ONE(nhad))
   {
     uint cnt = 0;
     NEXTHOP_WALK(nh, nhad)
@@ -1616,7 +1621,8 @@ nl_add_rte(struct krt_proto *p, rte *e)
     return err;
   }
 
-  return nl_send_route(p, e, NL_OP_ADD, a->dest, nhad);
+  return nl_send_route(p, e, NL_OP_ADD,
+      NEXTHOP_IS_REACHABLE(nhad) ? RTD_UNICAST : nhad->dest, nhad);
 }
 
 static inline int
@@ -1638,7 +1644,8 @@ nl_replace_rte(struct krt_proto *p, rte *e)
   rta *a = e->attrs;
   eattr *nhea = ea_find(a->eattrs, &ea_gen_nexthop);
   struct nexthop_adata *nhad = nhea ? (struct nexthop_adata *) nhea->u.ptr : NULL;
-  return nl_send_route(p, e, NL_OP_REPLACE, a->dest, nhad);
+  return nl_send_route(p, e, NL_OP_REPLACE,
+      NEXTHOP_IS_REACHABLE(nhad) ? RTD_UNICAST : nhad->dest, nhad);
 }
 
 
@@ -1901,8 +1908,6 @@ nl_parse_route(struct nl_parse_state *s, struct nlmsghdr *h)
   switch (i->rtm_type)
     {
     case RTN_UNICAST:
-      ra->dest = RTD_UNICAST;
-
       if (a[RTA_MULTIPATH])
         {
 	  struct nexthop_adata *nh = nl_parse_multipath(s, p, n, a[RTA_MULTIPATH], i->rtm_family, krt_src);
@@ -1953,15 +1958,40 @@ nl_parse_route(struct nl_parse_state *s, struct nlmsghdr *h)
 	    }
 	}
 
+#ifdef HAVE_MPLS_KERNEL
+      if ((i->rtm_family == AF_MPLS) && a[RTA_NEWDST] && !a[RTA_MULTIPATH])
+	nhad.nh.labels = rta_get_mpls(a[RTA_NEWDST], nhad.nh.label);
+
+      if (a[RTA_ENCAP] && a[RTA_ENCAP_TYPE] && !a[RTA_MULTIPATH])
+	{
+	  switch (rta_get_u16(a[RTA_ENCAP_TYPE]))
+	    {
+	      case LWTUNNEL_ENCAP_MPLS:
+		{
+		  struct rtattr *enca[BIRD_RTA_MAX];
+		  nl_attr_len = RTA_PAYLOAD(a[RTA_ENCAP]);
+		  nl_parse_attrs(RTA_DATA(a[RTA_ENCAP]), encap_mpls_want, enca, sizeof(enca));
+		  nhad.nh.labels = rta_get_mpls(enca[RTA_DST], nhad.nh.label);
+		  break;
+		}
+	      default:
+		SKIP("unknown encapsulation method %d\n", rta_get_u16(a[RTA_ENCAP_TYPE]));
+		break;
+	    }
+	}
+#endif
+
+      /* Finalize the nexthop */
+      nhad.ad.length = (void *) NEXTHOP_NEXT(&nhad.nh) - (void *) nhad.ad.data;
       break;
     case RTN_BLACKHOLE:
-      ra->dest = RTD_BLACKHOLE;
+      nhad.nhad = NEXTHOP_DEST_LITERAL(RTD_BLACKHOLE);
       break;
     case RTN_UNREACHABLE:
-      ra->dest = RTD_UNREACHABLE;
+      nhad.nhad = NEXTHOP_DEST_LITERAL(RTD_UNREACHABLE);
       break;
     case RTN_PROHIBIT:
-      ra->dest = RTD_PROHIBIT;
+      nhad.nhad = NEXTHOP_DEST_LITERAL(RTD_PROHIBIT);
       break;
     /* FIXME: What about RTN_THROW? */
     default:
@@ -1969,32 +1999,6 @@ nl_parse_route(struct nl_parse_state *s, struct nlmsghdr *h)
       return;
     }
 
-#ifdef HAVE_MPLS_KERNEL
-  if ((i->rtm_family == AF_MPLS) && a[RTA_NEWDST] && !a[RTA_MULTIPATH])
-    nhad.nh.labels = rta_get_mpls(a[RTA_NEWDST], nhad.nh.label);
-
-  if (a[RTA_ENCAP] && a[RTA_ENCAP_TYPE] && !a[RTA_MULTIPATH])
-    {
-      switch (rta_get_u16(a[RTA_ENCAP_TYPE]))
-	{
-	  case LWTUNNEL_ENCAP_MPLS:
-	    {
-	      struct rtattr *enca[BIRD_RTA_MAX];
-	      nl_attr_len = RTA_PAYLOAD(a[RTA_ENCAP]);
-	      nl_parse_attrs(RTA_DATA(a[RTA_ENCAP]), encap_mpls_want, enca, sizeof(enca));
-	      nhad.nh.labels = rta_get_mpls(enca[RTA_DST], nhad.nh.label);
-	      break;
-	    }
-	  default:
-	    SKIP("unknown encapsulation method %d\n", rta_get_u16(a[RTA_ENCAP_TYPE]));
-	    break;
-	}
-    }
-#endif
-
-  /* Finalize the nexthop */
-  nhad.ad.length = (void *) NEXTHOP_NEXT(&nhad.nh) - (void *) nhad.ad.data;
-
   if (i->rtm_scope != def_scope)
     ea_set_attr(&ra->eattrs,
 	EA_LITERAL_EMBEDDED(&ea_krt_scope, 0, i->rtm_scope));