Merge pull request #441 from bisdn/jogo_route_nnhs_fixes

nl_l3: fix nnhs handling a bit
bisdn · Jun 6, 2024 · dd3c2ff · dd3c2ff
2 parents dbdf8fe + 8e57584
commit dd3c2ff
Showing 1 changed file with 22 additions and 15 deletions.
diff --git a/src/netlink/nl_l3.cc b/src/netlink/nl_l3.cc
@@ -1849,22 +1849,23 @@ int nl_l3::add_l3_unicast_route(rtnl_route *r, bool update_route) {
         this, nh_params{net_params{rtnl_route_get_dst(r), nh.ifindex}, nh});
   }
 
-  switch (nnhs) {
-  case 0:
-    // Not yet determined next-hop, the rule must be installed to the switch
-    // pointing to controller and then updated after next-hop registration
-    rv = add_l3_unicast_route(rtnl_route_get_dst(r), 0, false, update_route,
-                              vrf_id);
-    break;
-  case 1:
-    // Single known next-hop
-    rv = add_l3_unicast_route(rtnl_route_get_dst(r), *l3_interfaces.begin(),
-                              false, update_route, vrf_id);
-    break;
-  default:
+  if (nnhs == 1) {
+    uint32_t route_dst_interface;
+
+    if (l3_interfaces.size() == 0) {
+      // Not yet resolved next-hop, or on-link route, the rule must be installed
+      // to the switch pointing to controller and then updated after neighbor
+      // registration.
+      route_dst_interface = 0;
+    } else {
+      // single, resolved nexthop
+      route_dst_interface = *l3_interfaces.begin(); /* resolved nexthop */
+    }
+    rv = add_l3_unicast_route(rtnl_route_get_dst(r), route_dst_interface, false,
+                              update_route, vrf_id);
+  } else {
     // create ecmp group
     rv = add_l3_ecmp_route(r, l3_interfaces, update_route);
-    break;
   }
 
   if (rv < 0) {
@@ -1926,13 +1927,19 @@ int nl_l3::del_l3_unicast_route(rtnl_route *r, bool keep_route) {
   int rv = 0;
   auto dst = rtnl_route_get_dst(r);
 
+  int nnhs = rtnl_route_get_nnexthops(r);
   uint16_t vrf_id = rtnl_route_get_table(r);
   // Routing table 254 id matches the main routing table on linux.
   // Adding a vrf with this id will collide with the main routing
   // table, but will enter the wrong info into the OFDPA tables
   if (vrf_id == MAIN_ROUTING_TABLE)
     vrf_id = 0;
 
+  if (nnhs == 0) {
+    LOG(WARNING) << __FUNCTION__ << ": no neighbours of route " << r;
+    return -ENOTSUP;
+  }
+
   if (rtnl_route_get_priority(r) > 0 &&
       rtnl_route_get_protocol(r) != RTPROT_KERNEL) {
     nl_route_query rq;
@@ -2017,7 +2024,7 @@ int nl_l3::del_l3_unicast_route(rtnl_route *r, bool keep_route) {
     return rv;
   }
 
-  if (neighs.size() > 1) {
+  if (nnhs > 1) {
     // get all l3 interfaces
     std::set<uint32_t> l3_interfaces; // all create l3 interface ids
     for (auto n : neighs) {