Add GTP-U plugin. VPP-694

Basic GTP-U feature

Change-Id: I31226f890a92c5303ac06e112ed7820cae52d9bd
Signed-off-by: Hongjun Ni <hongjun.ni@intel.com>

1 files changed, 1128 insertions, 0 deletions

diff --git a/src/plugins/gtpu/gtpu.c b/src/plugins/gtpu/gtpu.c
new file mode 100644
index 00000000000..6a5c5a34aeb
--- /dev/null
+++ b/src/plugins/gtpu/gtpu.c
@@ -0,0 +1,1128 @@
+/*
+ *------------------------------------------------------------------
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *------------------------------------------------------------------
+ */
+#include <stdint.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <inttypes.h>
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/fib/fib_entry.h>
+#include <vnet/fib/fib_table.h>
+#include <vnet/mfib/mfib_table.h>
+#include <vnet/adj/adj_mcast.h>
+#include <vnet/dpo/dpo.h>
+#include <vnet/plugin/plugin.h>
+#include <vpp/app/version.h>
+#include <gtpu/gtpu.h>
+
+
+gtpu_main_t gtpu_main;
+
+static u8 *
+format_decap_next (u8 * s, va_list * args)
+{
+  u32 next_index = va_arg (*args, u32);
+
+  switch (next_index)
+    {
+    case GTPU_INPUT_NEXT_DROP:
+      return format (s, "drop");
+    case GTPU_INPUT_NEXT_L2_INPUT:
+      return format (s, "l2");
+    default:
+      return format (s, "index %d", next_index);
+    }
+  return s;
+}
+
+u8 *
+format_gtpu_tunnel (u8 * s, va_list * args)
+{
+  gtpu_tunnel_t *t = va_arg (*args, gtpu_tunnel_t *);
+  gtpu_main_t *ngm = &gtpu_main;
+
+  s = format (s, "[%d] src %U dst %U teid %d sw_if_index %d ",
+	      t - ngm->tunnels,
+	      format_ip46_address, &t->src, IP46_TYPE_ANY,
+	      format_ip46_address, &t->dst, IP46_TYPE_ANY,
+	      t->teid, t->sw_if_index);
+
+  if (ip46_address_is_multicast (&t->dst))
+    s = format (s, "mcast_sw_if_index %d ", t->mcast_sw_if_index);
+
+  s = format (s, "encap_fib_index %d fib_entry_index %d decap_next %U\n",
+	      t->encap_fib_index, t->fib_entry_index,
+	      format_decap_next, t->decap_next_index);
+  return s;
+}
+
+static u8 *
+format_gtpu_name (u8 * s, va_list * args)
+{
+  u32 dev_instance = va_arg (*args, u32);
+  return format (s, "gtpu_tunnel%d", dev_instance);
+}
+
+static uword
+dummy_interface_tx (vlib_main_t * vm,
+		    vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  clib_warning ("you shouldn't be here, leaking buffers...");
+  return frame->n_vectors;
+}
+
+static clib_error_t *
+gtpu_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
+{
+  u32 hw_flags = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) ?
+    VNET_HW_INTERFACE_FLAG_LINK_UP : 0;
+  vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);
+
+  return /* no error */ 0;
+}
+
+/* *INDENT-OFF* */
+VNET_DEVICE_CLASS (gtpu_device_class,static) = {
+  .name = "GTPU",
+  .format_device_name = format_gtpu_name,
+  .format_tx_trace = format_gtpu_encap_trace,
+  .tx_function = dummy_interface_tx,
+  .admin_up_down_function = gtpu_interface_admin_up_down,
+};
+/* *INDENT-ON* */
+
+static u8 *
+format_gtpu_header_with_length (u8 * s, va_list * args)
+{
+  u32 dev_instance = va_arg (*args, u32);
+  s = format (s, "unimplemented dev %u", dev_instance);
+  return s;
+}
+
+/* *INDENT-OFF* */
+VNET_HW_INTERFACE_CLASS (gtpu_hw_class) =
+{
+  .name = "GTPU",
+  .format_header = format_gtpu_header_with_length,
+  .build_rewrite = default_build_rewrite,
+};
+/* *INDENT-ON* */
+
+static void
+gtpu_tunnel_restack_dpo (gtpu_tunnel_t * t)
+{
+  dpo_id_t dpo = DPO_INVALID;
+  u32 encap_index = ip46_address_is_ip4 (&t->dst) ?
+    gtpu4_encap_node.index : gtpu6_encap_node.index;
+  fib_forward_chain_type_t forw_type = ip46_address_is_ip4 (&t->dst) ?
+    FIB_FORW_CHAIN_TYPE_UNICAST_IP4 : FIB_FORW_CHAIN_TYPE_UNICAST_IP6;
+
+  fib_entry_contribute_forwarding (t->fib_entry_index, forw_type, &dpo);
+  dpo_stack_from_node (encap_index, &t->next_dpo, &dpo);
+  dpo_reset (&dpo);
+}
+
+static gtpu_tunnel_t *
+gtpu_tunnel_from_fib_node (fib_node_t * node)
+{
+  return ((gtpu_tunnel_t *) (((char *) node) -
+			     STRUCT_OFFSET_OF (gtpu_tunnel_t, node)));
+}
+
+/**
+ * Function definition to backwalk a FIB node -
+ * Here we will restack the new dpo of GTPU DIP to encap node.
+ */
+static fib_node_back_walk_rc_t
+gtpu_tunnel_back_walk (fib_node_t * node, fib_node_back_walk_ctx_t * ctx)
+{
+  gtpu_tunnel_restack_dpo (gtpu_tunnel_from_fib_node (node));
+  return (FIB_NODE_BACK_WALK_CONTINUE);
+}
+
+/**
+ * Function definition to get a FIB node from its index
+ */
+static fib_node_t *
+gtpu_tunnel_fib_node_get (fib_node_index_t index)
+{
+  gtpu_tunnel_t *t;
+  gtpu_main_t *gtm = &gtpu_main;
+
+  t = pool_elt_at_index (gtm->tunnels, index);
+
+  return (&t->node);
+}
+
+/**
+ * Function definition to inform the FIB node that its last lock has gone.
+ */
+static void
+gtpu_tunnel_last_lock_gone (fib_node_t * node)
+{
+  /*
+   * The GTPU tunnel is a root of the graph. As such
+   * it never has children and thus is never locked.
+   */
+  ASSERT (0);
+}
+
+/*
+ * Virtual function table registered by GTPU tunnels
+ * for participation in the FIB object graph.
+ */
+const static fib_node_vft_t gtpu_vft = {
+  .fnv_get = gtpu_tunnel_fib_node_get,
+  .fnv_last_lock = gtpu_tunnel_last_lock_gone,
+  .fnv_back_walk = gtpu_tunnel_back_walk,
+};
+
+
+#define foreach_copy_field                      \
+_(teid)                                          \
+_(mcast_sw_if_index)                            \
+_(encap_fib_index)                              \
+_(decap_next_index)                             \
+_(src)                                          \
+_(dst)
+
+static void
+ip_udp_gtpu_rewrite (gtpu_tunnel_t * t, bool is_ip6)
+{
+  union
+  {
+    ip4_gtpu_header_t *h4;
+    ip6_gtpu_header_t *h6;
+    u8 *rw;
+  } r =
+  {
+  .rw = 0};
+  int len = is_ip6 ? sizeof *r.h6 : sizeof *r.h4;
+
+  vec_validate_aligned (r.rw, len - 1, CLIB_CACHE_LINE_BYTES);
+
+  udp_header_t *udp;
+  gtpu_header_t *gtpu;
+  /* Fixed portion of the (outer) ip header */
+  if (!is_ip6)
+    {
+      ip4_header_t *ip = &r.h4->ip4;
+      udp = &r.h4->udp;
+      gtpu = &r.h4->gtpu;
+      ip->ip_version_and_header_length = 0x45;
+      ip->ttl = 254;
+      ip->protocol = IP_PROTOCOL_UDP;
+
+      ip->src_address = t->src.ip4;
+      ip->dst_address = t->dst.ip4;
+
+      /* we fix up the ip4 header length and checksum after-the-fact */
+      ip->checksum = ip4_header_checksum (ip);
+    }
+  else
+    {
+      ip6_header_t *ip = &r.h6->ip6;
+      udp = &r.h6->udp;
+      gtpu = &r.h6->gtpu;
+      ip->ip_version_traffic_class_and_flow_label =
+	clib_host_to_net_u32 (6 << 28);
+      ip->hop_limit = 255;
+      ip->protocol = IP_PROTOCOL_UDP;
+
+      ip->src_address = t->src.ip6;
+      ip->dst_address = t->dst.ip6;
+    }
+
+  /* UDP header, randomize src port on something, maybe? */
+  udp->src_port = clib_host_to_net_u16 (2152);
+  udp->dst_port = clib_host_to_net_u16 (UDP_DST_PORT_GTPU);
+
+  /* GTPU header */
+  gtpu->ver_flags = GTPU_V1_VER | GTPU_PT_GTP;
+  gtpu->type = GTPU_TYPE_GTPU;
+  gtpu->teid = clib_host_to_net_u32 (t->teid);
+
+  t->rewrite = r.rw;
+  /* Now only support 8-byte gtpu header. TBD */
+  _vec_len (t->rewrite) = sizeof (ip4_gtpu_header_t) - 4;
+
+  return;
+}
+
+static bool
+gtpu_decap_next_is_valid (gtpu_main_t * gtm, u32 is_ip6, u32 decap_next_index)
+{
+  vlib_main_t *vm = gtm->vlib_main;
+  u32 input_idx = (!is_ip6) ? gtpu4_input_node.index : gtpu6_input_node.index;
+  vlib_node_runtime_t *r = vlib_node_get_runtime (vm, input_idx);
+
+  return decap_next_index < r->n_next_nodes;
+}
+
+static void
+hash_set_key_copy (uword ** h, void *key, uword v)
+{
+  size_t ksz = hash_header (*h)->user;
+  void *copy = clib_mem_alloc (ksz);
+  clib_memcpy (copy, key, ksz);
+  hash_set_mem (*h, copy, v);
+}
+
+static void
+hash_unset_key_free (uword ** h, void *key)
+{
+  hash_pair_t *hp = hash_get_pair_mem (*h, key);
+  ASSERT (hp);
+  key = uword_to_pointer (hp->key, void *);
+  hash_unset_mem (*h, key);
+  clib_mem_free (key);
+}
+
+static uword
+vtep_addr_ref (ip46_address_t * ip)
+{
+  uword *vtep = ip46_address_is_ip4 (ip) ?
+    hash_get (gtpu_main.vtep4, ip->ip4.as_u32) :
+    hash_get_mem (gtpu_main.vtep6, &ip->ip6);
+  if (vtep)
+    return ++(*vtep);
+  ip46_address_is_ip4 (ip) ?
+    hash_set (gtpu_main.vtep4, ip->ip4.as_u32, 1) :
+    hash_set_key_copy (&gtpu_main.vtep6, &ip->ip6, 1);
+  return 1;
+}
+
+static uword
+vtep_addr_unref (ip46_address_t * ip)
+{
+  uword *vtep = ip46_address_is_ip4 (ip) ?
+    hash_get (gtpu_main.vtep4, ip->ip4.as_u32) :
+    hash_get_mem (gtpu_main.vtep6, &ip->ip6);
+  ASSERT (vtep);
+  if (--(*vtep) != 0)
+    return *vtep;
+  ip46_address_is_ip4 (ip) ?
+    hash_unset (gtpu_main.vtep4, ip->ip4.as_u32) :
+    hash_unset_key_free (&gtpu_main.vtep6, &ip->ip6);
+  return 0;
+}
+
+typedef CLIB_PACKED (union
+		     {
+		     struct
+		     {
+		     fib_node_index_t mfib_entry_index;
+		     adj_index_t mcast_adj_index;
+		     }; u64 as_u64;
+		     }) mcast_shared_t;
+
+static inline mcast_shared_t
+mcast_shared_get (ip46_address_t * ip)
+{
+  ASSERT (ip46_address_is_multicast (ip));
+  uword *p = hash_get_mem (gtpu_main.mcast_shared, ip);
+  ASSERT (p);
+  return (mcast_shared_t)
+  {
+  .as_u64 = *p};
+}
+
+static inline void
+mcast_shared_add (ip46_address_t * dst, fib_node_index_t mfei, adj_index_t ai)
+{
+  mcast_shared_t new_ep = {
+    .mcast_adj_index = ai,
+    .mfib_entry_index = mfei,
+  };
+
+  hash_set_key_copy (&gtpu_main.mcast_shared, dst, new_ep.as_u64);
+}
+
+static inline void
+mcast_shared_remove (ip46_address_t * dst)
+{
+  mcast_shared_t ep = mcast_shared_get (dst);
+
+  adj_unlock (ep.mcast_adj_index);
+  mfib_table_entry_delete_index (ep.mfib_entry_index, MFIB_SOURCE_GTPU);
+
+  hash_unset_key_free (&gtpu_main.mcast_shared, dst);
+}
+
+static inline fib_protocol_t
+fib_ip_proto (bool is_ip6)
+{
+  return (is_ip6) ? FIB_PROTOCOL_IP6 : FIB_PROTOCOL_IP4;
+}
+
+int vnet_gtpu_add_del_tunnel
+  (vnet_gtpu_add_del_tunnel_args_t * a, u32 * sw_if_indexp)
+{
+  gtpu_main_t *gtm = &gtpu_main;
+  gtpu_tunnel_t *t = 0;
+  vnet_main_t *vnm = gtm->vnet_main;
+  uword *p;
+  u32 hw_if_index = ~0;
+  u32 sw_if_index = ~0;
+  gtpu4_tunnel_key_t key4;
+  gtpu6_tunnel_key_t key6;
+  u32 is_ip6 = a->is_ip6;
+
+  if (!is_ip6)
+    {
+      key4.src = a->dst.ip4.as_u32;	/* decap src in key is encap dst in config */
+      key4.teid = clib_host_to_net_u32 (a->teid);
+      p = hash_get (gtm->gtpu4_tunnel_by_key, key4.as_u64);
+    }
+  else
+    {
+      key6.src = a->dst.ip6;
+      key6.teid = clib_host_to_net_u32 (a->teid);
+      p = hash_get_mem (gtm->gtpu6_tunnel_by_key, &key6);
+    }
+
+  if (a->is_add)
+    {
+      l2input_main_t *l2im = &l2input_main;
+
+      /* adding a tunnel: tunnel must not already exist */
+      if (p)
+	return VNET_API_ERROR_TUNNEL_EXIST;
+
+      /*if not set explicitly, default to l2 */
+      if (a->decap_next_index == ~0)
+	a->decap_next_index = GTPU_INPUT_NEXT_L2_INPUT;
+      if (!gtpu_decap_next_is_valid (gtm, is_ip6, a->decap_next_index))
+	return VNET_API_ERROR_INVALID_DECAP_NEXT;
+
+      pool_get_aligned (gtm->tunnels, t, CLIB_CACHE_LINE_BYTES);
+      memset (t, 0, sizeof (*t));
+
+      /* copy from arg structure */
+#define _(x) t->x = a->x;
+      foreach_copy_field;
+#undef _
+
+      ip_udp_gtpu_rewrite (t, is_ip6);
+
+      /* copy the key */
+      if (is_ip6)
+	hash_set_key_copy (&gtm->gtpu6_tunnel_by_key, &key6,
+			   t - gtm->tunnels);
+      else
+	hash_set (gtm->gtpu4_tunnel_by_key, key4.as_u64, t - gtm->tunnels);
+
+      vnet_hw_interface_t *hi;
+      if (vec_len (gtm->free_gtpu_tunnel_hw_if_indices) > 0)
+	{
+	  vnet_interface_main_t *im = &vnm->interface_main;
+	  hw_if_index = gtm->free_gtpu_tunnel_hw_if_indices
+	    [vec_len (gtm->free_gtpu_tunnel_hw_if_indices) - 1];
+	  _vec_len (gtm->free_gtpu_tunnel_hw_if_indices) -= 1;
+
+	  hi = vnet_get_hw_interface (vnm, hw_if_index);
+	  hi->dev_instance = t - gtm->tunnels;
+	  hi->hw_instance = hi->dev_instance;
+
+	  /* clear old stats of freed tunnel before reuse */
+	  sw_if_index = hi->sw_if_index;
+	  vnet_interface_counter_lock (im);
+	  vlib_zero_combined_counter
+	    (&im->combined_sw_if_counters[VNET_INTERFACE_COUNTER_TX],
+	     sw_if_index);
+	  vlib_zero_combined_counter (&im->combined_sw_if_counters
+				      [VNET_INTERFACE_COUNTER_RX],
+				      sw_if_index);
+	  vlib_zero_simple_counter (&im->sw_if_counters
+				    [VNET_INTERFACE_COUNTER_DROP],
+				    sw_if_index);
+	  vnet_interface_counter_unlock (im);
+	}
+      else
+	{
+	  hw_if_index = vnet_register_interface
+	    (vnm, gtpu_device_class.index, t - gtm->tunnels,
+	     gtpu_hw_class.index, t - gtm->tunnels);
+	  hi = vnet_get_hw_interface (vnm, hw_if_index);
+	}
+
+      t->hw_if_index = hw_if_index;
+      t->sw_if_index = sw_if_index = hi->sw_if_index;
+
+      vec_validate_init_empty (gtm->tunnel_index_by_sw_if_index, sw_if_index,
+			       ~0);
+      gtm->tunnel_index_by_sw_if_index[sw_if_index] = t - gtm->tunnels;
+
+      /* setup l2 input config with l2 feature and bd 0 to drop packet */
+      vec_validate (l2im->configs, sw_if_index);
+      l2im->configs[sw_if_index].feature_bitmap = L2INPUT_FEAT_DROP;
+      l2im->configs[sw_if_index].bd_index = 0;
+
+      vnet_sw_interface_t *si = vnet_get_sw_interface (vnm, sw_if_index);
+      si->flags &= ~VNET_SW_INTERFACE_FLAG_HIDDEN;
+      vnet_sw_interface_set_flags (vnm, sw_if_index,
+				   VNET_SW_INTERFACE_FLAG_ADMIN_UP);
+
+      fib_node_init (&t->node, gtm->fib_node_type);
+      fib_prefix_t tun_dst_pfx;
+      u32 encap_index = !is_ip6 ?
+	gtpu4_encap_node.index : gtpu6_encap_node.index;
+      vnet_flood_class_t flood_class = VNET_FLOOD_CLASS_TUNNEL_NORMAL;
+
+      fib_prefix_from_ip46_addr (&t->dst, &tun_dst_pfx);
+      if (!ip46_address_is_multicast (&t->dst))
+	{
+	  /* Unicast tunnel -
+	   * source the FIB entry for the tunnel's destination
+	   * and become a child thereof. The tunnel will then get poked
+	   * when the forwarding for the entry updates, and the tunnel can
+	   * re-stack accordingly
+	   */
+	  vtep_addr_ref (&t->src);
+	  t->fib_entry_index = fib_table_entry_special_add
+	    (t->encap_fib_index, &tun_dst_pfx, FIB_SOURCE_RR,
+	     FIB_ENTRY_FLAG_NONE);
+	  t->sibling_index = fib_entry_child_add
+	    (t->fib_entry_index, gtm->fib_node_type, t - gtm->tunnels);
+	  gtpu_tunnel_restack_dpo (t);
+	}
+      else
+	{
+	  /* Multicast tunnel -
+	   * as the same mcast group can be used for mutiple mcast tunnels
+	   * with different VNIs, create the output fib adjecency only if
+	   * it does not already exist
+	   */
+	  fib_protocol_t fp = fib_ip_proto (is_ip6);
+
+	  if (vtep_addr_ref (&t->dst) == 1)
+	    {
+	      fib_node_index_t mfei;
+	      adj_index_t ai;
+	      fib_route_path_t path = {
+		.frp_proto = fp,
+		.frp_addr = zero_addr,
+		.frp_sw_if_index = 0xffffffff,
+		.frp_fib_index = ~0,
+		.frp_weight = 0,
+		.frp_flags = FIB_ROUTE_PATH_LOCAL,
+	      };
+	      const mfib_prefix_t mpfx = {
+		.fp_proto = fp,
+		.fp_len = (is_ip6 ? 128 : 32),
+		.fp_grp_addr = tun_dst_pfx.fp_addr,
+	      };
+
+	      /*
+	       * Setup the (*,G) to receive traffic on the mcast group
+	       *  - the forwarding interface is for-us
+	       *  - the accepting interface is that from the API
+	       */
+	      mfib_table_entry_path_update (t->encap_fib_index,
+					    &mpfx,
+					    MFIB_SOURCE_GTPU,
+					    &path, MFIB_ITF_FLAG_FORWARD);
+
+	      path.frp_sw_if_index = a->mcast_sw_if_index;
+	      path.frp_flags = FIB_ROUTE_PATH_FLAG_NONE;
+	      mfei = mfib_table_entry_path_update (t->encap_fib_index,
+						   &mpfx,
+						   MFIB_SOURCE_GTPU,
+						   &path,
+						   MFIB_ITF_FLAG_ACCEPT);
+
+	      /*
+	       * Create the mcast adjacency to send traffic to the group
+	       */
+	      ai = adj_mcast_add_or_lock (fp,
+					  fib_proto_to_link (fp),
+					  a->mcast_sw_if_index);
+
+	      /*
+	       * create a new end-point
+	       */
+	      mcast_shared_add (&t->dst, mfei, ai);
+	    }
+
+	  dpo_id_t dpo = DPO_INVALID;
+	  mcast_shared_t ep = mcast_shared_get (&t->dst);
+
+	  /* Stack shared mcast dst mac addr rewrite on encap */
+	  dpo_set (&dpo, DPO_ADJACENCY_MCAST,
+		   fib_proto_to_dpo (fp), ep.mcast_adj_index);
+
+	  dpo_stack_from_node (encap_index, &t->next_dpo, &dpo);
+
+	  dpo_reset (&dpo);
+	  flood_class = VNET_FLOOD_CLASS_TUNNEL_MASTER;
+	}
+
+      /* Set gtpu tunnel output node */
+      hi->output_node_index = encap_index;
+
+      vnet_get_sw_interface (vnet_get_main (), sw_if_index)->flood_class =
+	flood_class;
+    }
+  else
+    {
+      /* deleting a tunnel: tunnel must exist */
+      if (!p)
+	return VNET_API_ERROR_NO_SUCH_ENTRY;
+
+      t = pool_elt_at_index (gtm->tunnels, p[0]);
+      sw_if_index = t->sw_if_index;
+
+      vnet_sw_interface_set_flags (vnm, t->sw_if_index, 0 /* down */ );
+      vnet_sw_interface_t *si = vnet_get_sw_interface (vnm, t->sw_if_index);
+      si->flags |= VNET_SW_INTERFACE_FLAG_HIDDEN;
+
+      /* make sure tunnel is removed from l2 bd or xconnect */
+      set_int_l2_mode (gtm->vlib_main, vnm, MODE_L3, t->sw_if_index, 0, 0, 0,
+		       0);
+      vec_add1 (gtm->free_gtpu_tunnel_hw_if_indices, t->hw_if_index);
+
+      gtm->tunnel_index_by_sw_if_index[t->sw_if_index] = ~0;
+
+      if (!is_ip6)
+	hash_unset (gtm->gtpu4_tunnel_by_key, key4.as_u64);
+      else
+	hash_unset_key_free (&gtm->gtpu6_tunnel_by_key, &key6);
+
+      if (!ip46_address_is_multicast (&t->dst))
+	{
+	  vtep_addr_unref (&t->src);
+	  fib_entry_child_remove (t->fib_entry_index, t->sibling_index);
+	  fib_table_entry_delete_index (t->fib_entry_index, FIB_SOURCE_RR);
+	}
+      else if (vtep_addr_unref (&t->dst) == 0)
+	{
+	  mcast_shared_remove (&t->dst);
+	}
+
+      fib_node_deinit (&t->node);
+      vec_free (t->rewrite);
+      pool_put (gtm->tunnels, t);
+    }
+
+  if (sw_if_indexp)
+    *sw_if_indexp = sw_if_index;
+
+  return 0;
+}
+
+static uword
+get_decap_next_for_node (u32 node_index, u32 ipv4_set)
+{
+  gtpu_main_t *gtm = &gtpu_main;
+  vlib_main_t *vm = gtm->vlib_main;
+  uword input_node = (ipv4_set) ? gtpu4_input_node.index :
+    gtpu6_input_node.index;
+
+  return vlib_node_add_next (vm, input_node, node_index);
+}
+
+static uword
+unformat_decap_next (unformat_input_t * input, va_list * args)
+{
+  u32 *result = va_arg (*args, u32 *);
+  u32 ipv4_set = va_arg (*args, int);
+  gtpu_main_t *gtm = &gtpu_main;
+  vlib_main_t *vm = gtm->vlib_main;
+  u32 node_index;
+  u32 tmp;
+
+  if (unformat (input, "l2"))
+    *result = GTPU_INPUT_NEXT_L2_INPUT;
+  else if (unformat (input, "node %U", unformat_vlib_node, vm, &node_index))
+    *result = get_decap_next_for_node (node_index, ipv4_set);
+  else if (unformat (input, "%d", &tmp))
+    *result = tmp;
+  else
+    return 0;
+  return 1;
+}
+
+static clib_error_t *
+gtpu_add_del_tunnel_command_fn (vlib_main_t * vm,
+				unformat_input_t * input,
+				vlib_cli_command_t * cmd)
+{
+  unformat_input_t _line_input, *line_input = &_line_input;
+  ip46_address_t src, dst;
+  u8 is_add = 1;
+  u8 src_set = 0;
+  u8 dst_set = 0;
+  u8 grp_set = 0;
+  u8 ipv4_set = 0;
+  u8 ipv6_set = 0;
+  u32 encap_fib_index = 0;
+  u32 mcast_sw_if_index = ~0;
+  u32 decap_next_index = GTPU_INPUT_NEXT_L2_INPUT;
+  u32 teid = 0;
+  u32 tmp;
+  int rv;
+  vnet_gtpu_add_del_tunnel_args_t _a, *a = &_a;
+  u32 tunnel_sw_if_index;
+  clib_error_t *error = NULL;
+
+  /* Cant "universally zero init" (={0}) due to GCC bug 53119 */
+  memset (&src, 0, sizeof src);
+  memset (&dst, 0, sizeof dst);
+
+  /* Get a line of input. */
+  if (!unformat_user (input, unformat_line_input, line_input))
+    return 0;
+
+  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (line_input, "del"))
+	{
+	  is_add = 0;
+	}
+      else if (unformat (line_input, "src %U",
+			 unformat_ip4_address, &src.ip4))
+	{
+	  src_set = 1;
+	  ipv4_set = 1;
+	}
+      else if (unformat (line_input, "dst %U",
+			 unformat_ip4_address, &dst.ip4))
+	{
+	  dst_set = 1;
+	  ipv4_set = 1;
+	}
+      else if (unformat (line_input, "src %U",
+			 unformat_ip6_address, &src.ip6))
+	{
+	  src_set = 1;
+	  ipv6_set = 1;
+	}
+      else if (unformat (line_input, "dst %U",
+			 unformat_ip6_address, &dst.ip6))
+	{
+	  dst_set = 1;
+	  ipv6_set = 1;
+	}
+      else if (unformat (line_input, "group %U %U",
+			 unformat_ip4_address, &dst.ip4,
+			 unformat_vnet_sw_interface,
+			 vnet_get_main (), &mcast_sw_if_index))
+	{
+	  grp_set = dst_set = 1;
+	  ipv4_set = 1;
+	}
+      else if (unformat (line_input, "group %U %U",
+			 unformat_ip6_address, &dst.ip6,
+			 unformat_vnet_sw_interface,
+			 vnet_get_main (), &mcast_sw_if_index))
+	{
+	  grp_set = dst_set = 1;
+	  ipv6_set = 1;
+	}
+      else if (unformat (line_input, "encap-vrf-id %d", &tmp))
+	{
+	  encap_fib_index = fib_table_find (fib_ip_proto (ipv6_set), tmp);
+	  if (encap_fib_index == ~0)
+	    {
+	      error =
+		clib_error_return (0, "nonexistent encap-vrf-id %d", tmp);
+	      goto done;
+	    }
+	}
+      else if (unformat (line_input, "decap-next %U", unformat_decap_next,
+			 &decap_next_index, ipv4_set))
+	;
+      else if (unformat (line_input, "teid %d", &teid))
+	;
+      else
+	{
+	  error = clib_error_return (0, "parse error: '%U'",
+				     format_unformat_error, line_input);
+	  goto done;
+	}
+    }
+
+  if (src_set == 0)
+    {
+      error = clib_error_return (0, "tunnel src address not specified");
+      goto done;
+    }
+
+  if (dst_set == 0)
+    {
+      error = clib_error_return (0, "tunnel dst address not specified");
+      goto done;
+    }
+
+  if (grp_set && !ip46_address_is_multicast (&dst))
+    {
+      error = clib_error_return (0, "tunnel group address not multicast");
+      goto done;
+    }
+
+  if (grp_set == 0 && ip46_address_is_multicast (&dst))
+    {
+      error = clib_error_return (0, "dst address must be unicast");
+      goto done;
+    }
+
+  if (grp_set && mcast_sw_if_index == ~0)
+    {
+      error = clib_error_return (0, "tunnel nonexistent multicast device");
+      goto done;
+    }
+
+  if (ipv4_set && ipv6_set)
+    {
+      error = clib_error_return (0, "both IPv4 and IPv6 addresses specified");
+      goto done;
+    }
+
+  if (ip46_address_cmp (&src, &dst) == 0)
+    {
+      error = clib_error_return (0, "src and dst addresses are identical");
+      goto done;
+    }
+
+  if (decap_next_index == ~0)
+    {
+      error = clib_error_return (0, "next node not found");
+      goto done;
+    }
+
+  memset (a, 0, sizeof (*a));
+
+  a->is_add = is_add;
+  a->is_ip6 = ipv6_set;
+
+#define _(x) a->x = x;
+  foreach_copy_field;
+#undef _
+
+  rv = vnet_gtpu_add_del_tunnel (a, &tunnel_sw_if_index);
+
+  switch (rv)
+    {
+    case 0:
+      if (is_add)
+	vlib_cli_output (vm, "%U\n", format_vnet_sw_if_index_name,
+			 vnet_get_main (), tunnel_sw_if_index);
+      break;
+
+    case VNET_API_ERROR_TUNNEL_EXIST:
+      error = clib_error_return (0, "tunnel already exists...");
+      goto done;
+
+    case VNET_API_ERROR_NO_SUCH_ENTRY:
+      error = clib_error_return (0, "tunnel does not exist...");
+      goto done;
+
+    default:
+      error = clib_error_return
+	(0, "vnet_gtpu_add_del_tunnel returned %d", rv);
+      goto done;
+    }
+
+done:
+  unformat_free (line_input);
+
+  return error;
+}
+
+/*?
+ * Add or delete a GTPU Tunnel.
+ *
+ * GTPU provides the features needed to allow L2 bridge domains (BDs)
+ * to span multiple servers. This is done by building an L2 overlay on
+ * top of an L3 network underlay using GTPU tunnels.
+ *
+ * This makes it possible for servers to be co-located in the same data
+ * center or be separated geographically as long as they are reachable
+ * through the underlay L3 network.
+ *
+ * You can refer to this kind of L2 overlay bridge domain as a GTPU
+ * (Virtual eXtensible VLAN) segment.
+ *
+ * @cliexpar
+ * Example of how to create a GTPU Tunnel:
+ * @cliexcmd{create gtpu tunnel src 10.0.3.1 dst 10.0.3.3 teid 13 encap-vrf-id 7}
+ * Example of how to delete a GTPU Tunnel:
+ * @cliexcmd{create gtpu tunnel src 10.0.3.1 dst 10.0.3.3 teid 13 del}
+ ?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (create_gtpu_tunnel_command, static) = {
+  .path = "create gtpu tunnel",
+  .short_help =
+  "create gtpu tunnel src <local-vtep-addr>"
+  " {dst <remote-vtep-addr>|group <mcast-vtep-addr> <intf-name>} teid <nn>"
+  " [encap-vrf-id <nn>] [decap-next [l2|node <name>]] [del]",
+  .function = gtpu_add_del_tunnel_command_fn,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+show_gtpu_tunnel_command_fn (vlib_main_t * vm,
+			     unformat_input_t * input,
+			     vlib_cli_command_t * cmd)
+{
+  gtpu_main_t *gtm = &gtpu_main;
+  gtpu_tunnel_t *t;
+
+  if (pool_elts (gtm->tunnels) == 0)
+    vlib_cli_output (vm, "No gtpu tunnels configured...");
+
+  pool_foreach (t, gtm->tunnels, (
+				   {
+				   vlib_cli_output (vm, "%U",
+						    format_gtpu_tunnel, t);
+				   }
+		));
+
+  return 0;
+}
+
+/*?
+ * Display all the GTPU Tunnel entries.
+ *
+ * @cliexpar
+ * Example of how to display the GTPU Tunnel entries:
+ * @cliexstart{show gtpu tunnel}
+ * [0] src 10.0.3.1 dst 10.0.3.3 teid 13 encap_fib_index 0 sw_if_index 5 decap_next l2
+ * @cliexend
+ ?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (show_gtpu_tunnel_command, static) = {
+    .path = "show gtpu tunnel",
+    .short_help = "show gtpu tunnel",
+    .function = show_gtpu_tunnel_command_fn,
+};
+/* *INDENT-ON* */
+
+void
+vnet_int_gtpu_bypass_mode (u32 sw_if_index, u8 is_ip6, u8 is_enable)
+{
+  if (is_ip6)
+    vnet_feature_enable_disable ("ip6-unicast", "ip6-gtpu-bypass",
+				 sw_if_index, is_enable, 0, 0);
+  else
+    vnet_feature_enable_disable ("ip4-unicast", "ip4-gtpu-bypass",
+				 sw_if_index, is_enable, 0, 0);
+}
+
+static clib_error_t *
+set_ip_gtpu_bypass (u32 is_ip6,
+		    unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  unformat_input_t _line_input, *line_input = &_line_input;
+  vnet_main_t *vnm = vnet_get_main ();
+  clib_error_t *error = 0;
+  u32 sw_if_index, is_enable;
+
+  sw_if_index = ~0;
+  is_enable = 1;
+
+  if (!unformat_user (input, unformat_line_input, line_input))
+    return 0;
+
+  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat_user
+	  (line_input, unformat_vnet_sw_interface, vnm, &sw_if_index))
+	;
+      else if (unformat (line_input, "del"))
+	is_enable = 0;
+      else
+	{
+	  error = unformat_parse_error (line_input);
+	  goto done;
+	}
+    }
+
+  if (~0 == sw_if_index)
+    {
+      error = clib_error_return (0, "unknown interface `%U'",
+				 format_unformat_error, line_input);
+      goto done;
+    }
+
+  vnet_int_gtpu_bypass_mode (sw_if_index, is_ip6, is_enable);
+
+done:
+  unformat_free (line_input);
+
+  return error;
+}
+
+static clib_error_t *
+set_ip4_gtpu_bypass (vlib_main_t * vm,
+		     unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  return set_ip_gtpu_bypass (0, input, cmd);
+}
+
+/*?
+ * This command adds the 'ip4-gtpu-bypass' graph node for a given interface.
+ * By adding the IPv4 gtpu-bypass graph node to an interface, the node checks
+ *  for and validate input gtpu packet and bypass ip4-lookup, ip4-local,
+ * ip4-udp-lookup nodes to speedup gtpu packet forwarding. This node will
+ * cause extra overhead to for non-gtpu packets which is kept at a minimum.
+ *
+ * @cliexpar
+ * @parblock
+ * Example of graph node before ip4-gtpu-bypass is enabled:
+ * @cliexstart{show vlib graph ip4-gtpu-bypass}
+ *            Name                      Next                    Previous
+ * ip4-gtpu-bypass                error-drop [0]
+ *                                gtpu4-input [1]
+ *                                 ip4-lookup [2]
+ * @cliexend
+ *
+ * Example of how to enable ip4-gtpu-bypass on an interface:
+ * @cliexcmd{set interface ip gtpu-bypass GigabitEthernet2/0/0}
+ *
+ * Example of graph node after ip4-gtpu-bypass is enabled:
+ * @cliexstart{show vlib graph ip4-gtpu-bypass}
+ *            Name                      Next                    Previous
+ * ip4-gtpu-bypass                error-drop [0]               ip4-input
+ *                                gtpu4-input [1]        ip4-input-no-checksum
+ *                                 ip4-lookup [2]
+ * @cliexend
+ *
+ * Example of how to display the feature enabed on an interface:
+ * @cliexstart{show ip interface features GigabitEthernet2/0/0}
+ * IP feature paths configured on GigabitEthernet2/0/0...
+ * ...
+ * ipv4 unicast:
+ *   ip4-gtpu-bypass
+ *   ip4-lookup
+ * ...
+ * @cliexend
+ *
+ * Example of how to disable ip4-gtpu-bypass on an interface:
+ * @cliexcmd{set interface ip gtpu-bypass GigabitEthernet2/0/0 del}
+ * @endparblock
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (set_interface_ip_gtpu_bypass_command, static) = {
+  .path = "set interface ip gtpu-bypass",
+  .function = set_ip4_gtpu_bypass,
+  .short_help = "set interface ip gtpu-bypass <interface> [del]",
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+set_ip6_gtpu_bypass (vlib_main_t * vm,
+		     unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  return set_ip_gtpu_bypass (1, input, cmd);
+}
+
+/*?
+ * This command adds the 'ip6-gtpu-bypass' graph node for a given interface.
+ * By adding the IPv6 gtpu-bypass graph node to an interface, the node checks
+ *  for and validate input gtpu packet and bypass ip6-lookup, ip6-local,
+ * ip6-udp-lookup nodes to speedup gtpu packet forwarding. This node will
+ * cause extra overhead to for non-gtpu packets which is kept at a minimum.
+ *
+ * @cliexpar
+ * @parblock
+ * Example of graph node before ip6-gtpu-bypass is enabled:
+ * @cliexstart{show vlib graph ip6-gtpu-bypass}
+ *            Name                      Next                    Previous
+ * ip6-gtpu-bypass                error-drop [0]
+ *                                gtpu6-input [1]
+ *                                 ip6-lookup [2]
+ * @cliexend
+ *
+ * Example of how to enable ip6-gtpu-bypass on an interface:
+ * @cliexcmd{set interface ip6 gtpu-bypass GigabitEthernet2/0/0}
+ *
+ * Example of graph node after ip6-gtpu-bypass is enabled:
+ * @cliexstart{show vlib graph ip6-gtpu-bypass}
+ *            Name                      Next                    Previous
+ * ip6-gtpu-bypass                error-drop [0]               ip6-input
+ *                                gtpu6-input [1]        ip4-input-no-checksum
+ *                                 ip6-lookup [2]
+ * @cliexend
+ *
+ * Example of how to display the feature enabed on an interface:
+ * @cliexstart{show ip interface features GigabitEthernet2/0/0}
+ * IP feature paths configured on GigabitEthernet2/0/0...
+ * ...
+ * ipv6 unicast:
+ *   ip6-gtpu-bypass
+ *   ip6-lookup
+ * ...
+ * @cliexend
+ *
+ * Example of how to disable ip6-gtpu-bypass on an interface:
+ * @cliexcmd{set interface ip6 gtpu-bypass GigabitEthernet2/0/0 del}
+ * @endparblock
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (set_interface_ip6_gtpu_bypass_command, static) = {
+  .path = "set interface ip6 gtpu-bypass",
+  .function = set_ip6_gtpu_bypass,
+  .short_help = "set interface ip gtpu-bypass <interface> [del]",
+};
+/* *INDENT-ON* */
+
+clib_error_t *
+gtpu_init (vlib_main_t * vm)
+{
+  gtpu_main_t *gtm = &gtpu_main;
+
+  gtm->vnet_main = vnet_get_main ();
+  gtm->vlib_main = vm;
+
+  /* initialize the ip6 hash */
+  gtm->gtpu6_tunnel_by_key = hash_create_mem (0,
+					      sizeof (gtpu6_tunnel_key_t),
+					      sizeof (uword));
+  gtm->vtep6 = hash_create_mem (0, sizeof (ip6_address_t), sizeof (uword));
+  gtm->mcast_shared = hash_create_mem (0,
+				       sizeof (ip46_address_t),
+				       sizeof (mcast_shared_t));
+
+  udp_register_dst_port (vm, UDP_DST_PORT_GTPU,
+			 gtpu4_input_node.index, /* is_ip4 */ 1);
+  udp_register_dst_port (vm, UDP_DST_PORT_GTPU6,
+			 gtpu6_input_node.index, /* is_ip4 */ 0);
+
+  gtm->fib_node_type = fib_node_register_new_type (&gtpu_vft);
+
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (gtpu_init);
+
+/* *INDENT-OFF* */
+VLIB_PLUGIN_REGISTER () = {
+    .version = VPP_BUILD_VER,
+    .description = "GTPv1-U",
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */