zebra: fix recursive-routes via ifindex routes
Signed-off-by: Christian Franke <chris@opensourcerouting.org>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/zebra/zebra_rib.c b/zebra/zebra_rib.c
index 301e0cc..3106523 100644
--- a/zebra/zebra_rib.c
+++ b/zebra/zebra_rib.c
@@ -500,16 +500,37 @@
resolved_hop = XCALLOC(MTYPE_NEXTHOP, sizeof (struct nexthop));
SET_FLAG (resolved_hop->flags, NEXTHOP_FLAG_ACTIVE);
+ /* If the resolving route specifies a gateway, use it */
+ if (newhop->type == NEXTHOP_TYPE_IPV4
+ || newhop->type == NEXTHOP_TYPE_IPV4_IFINDEX
+ || newhop->type == NEXTHOP_TYPE_IPV4_IFNAME)
+ {
+ resolved_hop->type = newhop->type;
+ resolved_hop->gate.ipv4 = newhop->gate.ipv4;
- resolved_hop->type = newhop->type;
- if (newhop->type == NEXTHOP_TYPE_IPV4 ||
- newhop->type == NEXTHOP_TYPE_IPV4_IFINDEX)
- resolved_hop->gate.ipv4 = newhop->gate.ipv4;
+ if (newhop->ifindex)
+ {
+ resolved_hop->type = NEXTHOP_TYPE_IPV4_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 (newhop->type == NEXTHOP_TYPE_IFINDEX
- || newhop->type == NEXTHOP_TYPE_IFNAME
- || newhop->type == NEXTHOP_TYPE_IPV4_IFINDEX)
- resolved_hop->ifindex = newhop->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;
+ }
_nexthop_add(&nexthop->resolved, resolved_hop);
}
@@ -622,18 +643,30 @@
resolved_hop = XCALLOC(MTYPE_NEXTHOP, sizeof (struct nexthop));
SET_FLAG (resolved_hop->flags, NEXTHOP_FLAG_ACTIVE);
-
- resolved_hop->type = newhop->type;
+ /* See nexthop_active_ipv4 for a description how the
+ * resolved nexthop is constructed. */
if (newhop->type == NEXTHOP_TYPE_IPV6
|| newhop->type == NEXTHOP_TYPE_IPV6_IFINDEX
|| newhop->type == NEXTHOP_TYPE_IPV6_IFNAME)
- resolved_hop->gate.ipv6 = newhop->gate.ipv6;
+ {
+ resolved_hop->type = newhop->type;
+ resolved_hop->gate.ipv6 = newhop->gate.ipv6;
+
+ if (newhop->ifindex)
+ {
+ resolved_hop->type = NEXTHOP_TYPE_IPV6_IFINDEX;
+ resolved_hop->ifindex = newhop->ifindex;
+ }
+ }
if (newhop->type == NEXTHOP_TYPE_IFINDEX
- || newhop->type == NEXTHOP_TYPE_IFNAME
- || newhop->type == NEXTHOP_TYPE_IPV6_IFINDEX
- || newhop->type == NEXTHOP_TYPE_IPV6_IFNAME)
- resolved_hop->ifindex = newhop->ifindex;
+ || newhop->type == NEXTHOP_TYPE_IFNAME)
+ {
+ resolved_hop->flags |= NEXTHOP_FLAG_ONLINK;
+ resolved_hop->type = NEXTHOP_TYPE_IPV6_IFINDEX;
+ resolved_hop->gate.ipv6 = nexthop->gate.ipv6;
+ resolved_hop->ifindex = newhop->ifindex;
+ }
_nexthop_add(&nexthop->resolved, resolved_hop);
}