zebra: Add link_nsid to zebra interface

Create VRF and interfaces:

    ip netns add vrf1
    ip link add veth1 index 100 type veth
    ip link add link veth1 veth1.200 type vlan id 200
    ip link set veth1.200 netns vrf1
    ip -n vrf1 link add veth2 index 100 type veth

After reloading zebra, "show interface veth1.200" shows wrong parent
interface:

    test# show interface veth1.200
    Interface veth1.200 is down
      ...
      Parent interface: veth2

This is because veth1.200 and veth1 are in different netns, and veth2
happens to have the same ifindex as veth1, in the same netns of
veth1.200.
When looking for parent, link-ifindex 100 should be looked up within
link-netns, rather than that of the child interface.

Add link_nsid to zebra interface, so that the <link_nsid, link_ifindex>
pair can uniquely identify the link interface.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>

1 files changed, 15 insertions, 8 deletions

diff --git a/zebra/interface.c b/zebra/interface.c
index 1ba5e972f8..02715ef384 100644
--- a/zebra/interface.c
+++ b/zebra/interface.c
@@ -137,6 +137,8 @@ static int if_zebra_new_hook(struct interface *ifp)
 	zebra_if->multicast = IF_ZEBRA_DATA_UNSPEC;
 	zebra_if->shutdown = IF_ZEBRA_DATA_OFF;
 
+	zebra_if->link_nsid = NS_UNKNOWN;
+
 	zebra_if_nhg_dependents_init(zebra_if);
 
 	zebra_ptm_if_init(zebra_if);
@@ -305,6 +307,14 @@ struct interface *if_lookup_by_name_per_ns(struct zebra_ns *ns,
 	return NULL;
 }
 
+struct interface *if_lookup_by_index_per_nsid(ns_id_t ns_id, uint32_t ifindex)
+{
+	struct zebra_ns *zns;
+
+	zns = zebra_ns_lookup(ns_id);
+	return zns ? if_lookup_by_index_per_ns(zns, ifindex) : NULL;
+}
+
 const char *ifindex2ifname_per_ns(struct zebra_ns *zns, unsigned int ifindex)
 {
 	struct interface *ifp;
@@ -991,7 +1001,6 @@ void if_up(struct interface *ifp, bool install_connected)
 {
 	struct zebra_if *zif;
 	struct interface *link_if;
-	struct zebra_vrf *zvrf = ifp->vrf->info;
 
 	zif = ifp->info;
 	zif->up_count++;
@@ -1024,8 +1033,7 @@ void if_up(struct interface *ifp, bool install_connected)
 		link_if = ifp;
 		zebra_vxlan_svi_up(ifp, link_if);
 	} else if (IS_ZEBRA_IF_VLAN(ifp)) {
-		link_if = if_lookup_by_index_per_ns(zvrf->zns,
-						    zif->link_ifindex);
+		link_if = zif->link;
 		if (link_if)
 			zebra_vxlan_svi_up(ifp, link_if);
 	} else if (IS_ZEBRA_IF_MACVLAN(ifp)) {
@@ -1049,7 +1057,6 @@ void if_down(struct interface *ifp)
 {
 	struct zebra_if *zif;
 	struct interface *link_if;
-	struct zebra_vrf *zvrf = ifp->vrf->info;
 
 	zif = ifp->info;
 	zif->down_count++;
@@ -1068,8 +1075,7 @@ void if_down(struct interface *ifp)
 		link_if = ifp;
 		zebra_vxlan_svi_down(ifp, link_if);
 	} else if (IS_ZEBRA_IF_VLAN(ifp)) {
-		link_if = if_lookup_by_index_per_ns(zvrf->zns,
-						    zif->link_ifindex);
+		link_if = zif->link;
 		if (link_if)
 			zebra_vxlan_svi_down(ifp, link_if);
 	} else if (IS_ZEBRA_IF_MACVLAN(ifp)) {
@@ -1109,6 +1115,7 @@ void zebra_if_update_link(struct interface *ifp, ifindex_t link_ifindex,
 	if (IS_ZEBRA_IF_VETH(ifp))
 		return;
 	zif = (struct zebra_if *)ifp->info;
+	zif->link_nsid = ns_id;
 	zif->link_ifindex = link_ifindex;
 	zif->link = if_lookup_by_index_per_ns(zebra_ns_lookup(ns_id),
 					      link_ifindex);
@@ -1145,8 +1152,8 @@ void zebra_if_update_all_links(struct zebra_ns *zns)
 
 		/* update SVI linkages */
 		if ((zif->link_ifindex != IFINDEX_INTERNAL) && !zif->link) {
-			zif->link = if_lookup_by_index_per_ns(
-				zns, zif->link_ifindex);
+			zif->link = if_lookup_by_index_per_nsid(
+				zif->link_nsid, zif->link_ifindex);
 			if (IS_ZEBRA_DEBUG_KERNEL)
 				zlog_debug("interface %s/%d's lower fixup to %s/%d",
 						ifp->name, ifp->ifindex,