zebra: Layer-2 interface handling

Define interface types of interest and recognize the types. Store layer-2
information (VLAN Id, VNI etc.) for interfaces, process bridge interfaces
and map bridge members to bridge. Display all the additional information
to user (through "show interface").

Note: Only implemented for the netlink interface.

Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Reviewed-by:   Donald Sharp <sharpd@cumulusnetworks.com>

1 files changed, 238 insertions, 0 deletions

diff --git a/zebra/zebra_l2.c b/zebra/zebra_l2.c
new file mode 100644
index 000000000..5dd83baed
--- /dev/null
+++ b/zebra/zebra_l2.c
@@ -0,0 +1,238 @@
+/*
+ * Zebra Layer-2 interface handling code
+ * Copyright (C) 2016, 2017 Cumulus Networks, Inc.
+ *
+ * This file is part of FRR.
+ *
+ * FRR is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * FRR is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with FRR; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <zebra.h>
+
+#include "if.h"
+#include "prefix.h"
+#include "table.h"
+#include "memory.h"
+#include "log.h"
+#include "linklist.h"
+#include "stream.h"
+#include "hash.h"
+#include "jhash.h"
+
+#include "zebra/rib.h"
+#include "zebra/rt.h"
+#include "zebra/zebra_ns.h"
+#include "zebra/zserv.h"
+#include "zebra/debug.h"
+#include "zebra/interface.h"
+#include "zebra/zebra_memory.h"
+#include "zebra/zebra_vrf.h"
+#include "zebra/rt_netlink.h"
+#include "zebra/zebra_l2.h"
+
+/* definitions */
+
+/* static function declarations */
+
+/* Private functions */
+static void
+map_slaves_to_bridge (struct interface *br_if, int link)
+{
+  struct vrf *vrf;
+  struct listnode *node;
+  struct interface *ifp;
+
+  RB_FOREACH (vrf, vrf_name_head, &vrfs_by_name)
+    {
+      for (ALL_LIST_ELEMENTS_RO (vrf->iflist, node, ifp))
+        {
+          struct zebra_if *zif;
+          struct zebra_l2info_brslave *br_slave;
+
+          if (ifp->ifindex == IFINDEX_INTERNAL ||
+              !ifp->info)
+            continue;
+          if (!IS_ZEBRA_IF_BRIDGE_SLAVE (ifp))
+            continue;
+
+          /* NOTE: This assumes 'zebra_l2info_brslave' is the first field
+           * for any L2 interface.
+           */
+          zif = (struct zebra_if *) ifp->info;
+          br_slave = &zif->brslave_info;
+
+          if (link)
+            {
+              if (br_slave->bridge_ifindex == br_if->ifindex)
+                br_slave->br_if = br_if;
+            }
+          else
+            {
+              if (br_slave->br_if == br_if)
+                br_slave->br_if = NULL;
+            }
+        }
+    }
+}
+
+/* Public functions */
+void
+zebra_l2_map_slave_to_bridge (struct zebra_l2info_brslave *br_slave)
+{
+  struct interface *br_if;
+
+  /* TODO: Handle change of master */
+  br_if = if_lookup_by_index_per_ns (zebra_ns_lookup (NS_DEFAULT),
+                                     br_slave->bridge_ifindex);
+  if (br_if)
+    br_slave->br_if = br_if;
+}
+
+void
+zebra_l2_unmap_slave_from_bridge (struct zebra_l2info_brslave *br_slave)
+{
+  br_slave->br_if = NULL;
+}
+
+/*
+ * Handle Bridge interface add or update. Update relevant info,
+ * map slaves (if any) to the bridge.
+ */
+void
+zebra_l2_bridge_add_update (struct interface *ifp,
+                            struct zebra_l2info_bridge *bridge_info,
+                            int add)
+{
+  struct zebra_if *zif;
+
+  zif = ifp->info;
+  assert(zif);
+
+  /* Copy over the L2 information. */
+  memcpy (&zif->l2info.br, bridge_info, sizeof (*bridge_info));
+
+  /* Link all slaves to this bridge */
+  map_slaves_to_bridge (ifp, 1);
+}
+
+/*
+ * Handle Bridge interface delete.
+ */
+void
+zebra_l2_bridge_del (struct interface *ifp)
+{
+  /* Unlink all slaves to this bridge */
+  map_slaves_to_bridge (ifp, 0);
+}
+
+/*
+ * Update L2 info for a VLAN interface. Only relevant parameter is the
+ * VLAN Id and this cannot change.
+ */
+void
+zebra_l2_vlanif_update (struct interface *ifp,
+                        struct zebra_l2info_vlan *vlan_info)
+{
+  struct zebra_if *zif;
+
+  zif = ifp->info;
+  assert(zif);
+
+  /* Copy over the L2 information. */
+  memcpy (&zif->l2info.vl, vlan_info, sizeof (*vlan_info));
+}
+
+/*
+ * Update L2 info for a VxLAN interface. This is called upon interface
+ * addition as well as update. Upon add, need to invoke the VNI create
+ * function. Upon update, the params of interest are the local tunnel
+ * IP and VLAN mapping, but the latter is handled separately.
+ */
+void
+zebra_l2_vxlanif_add_update (struct interface *ifp,
+                             struct zebra_l2info_vxlan *vxlan_info,
+                             int add)
+{
+  struct zebra_if *zif;
+  struct in_addr old_vtep_ip;
+
+  zif = ifp->info;
+  assert(zif);
+
+  if (add)
+    {
+      memcpy (&zif->l2info.vxl, vxlan_info, sizeof (*vxlan_info));
+      return;
+    }
+
+  old_vtep_ip = zif->l2info.vxl.vtep_ip;
+  if (IPV4_ADDR_SAME(&old_vtep_ip, &vxlan_info->vtep_ip))
+    return;
+
+  zif->l2info.vxl.vtep_ip = vxlan_info->vtep_ip;
+}
+
+/*
+ * Handle change to VLAN to VNI mapping.
+ */
+void
+zebra_l2_vxlanif_update_access_vlan (struct interface *ifp,
+                                     vlanid_t access_vlan)
+{
+  struct zebra_if *zif;
+
+  zif = ifp->info;
+  assert(zif);
+
+  zif->l2info.vxl.access_vlan = access_vlan;
+}
+
+/*
+ * Handle VxLAN interface delete.
+ */
+void
+zebra_l2_vxlanif_del (struct interface *ifp)
+{
+  /* No action currently. */
+}
+
+/*
+ * Map or unmap interface from bridge.
+ * NOTE: It is currently assumped that an interface has to be unmapped
+ * from a bridge before it can be mapped to another bridge.
+ */
+void
+zebra_l2if_update_bridge_slave (struct interface *ifp,
+                                ifindex_t bridge_ifindex)
+{
+  struct zebra_if *zif;
+  ifindex_t old_bridge_ifindex;
+
+  zif = ifp->info;
+  assert(zif);
+
+  old_bridge_ifindex = zif->brslave_info.bridge_ifindex;
+  if (old_bridge_ifindex == bridge_ifindex)
+    return;
+
+  zif->brslave_info.bridge_ifindex = bridge_ifindex;
+
+  /* Set up or remove link with master */
+  if (bridge_ifindex != IFINDEX_INTERNAL)
+    zebra_l2_map_slave_to_bridge (&zif->brslave_info);
+  else if (old_bridge_ifindex != IFINDEX_INTERNAL)
+    zebra_l2_unmap_slave_from_bridge (&zif->brslave_info);
+}