L2 Emulation

L2 Emulation is a feautre that is applied to L2 ports to 'extract'
IP packets from the L2 path and inject them into the L3 path (i.e.
into the appropriate ip[4|6]_input node).
L3 routes in the table_id for that interface should then be configured
as DVR routes, therefore the forwarded packet has the L2 header
preserved and togehter the L3 routed system behaves like an L2 bridge.

Change-Id: I8effd7e2f4c67ee277b73c7bc79aa3e5a3e34d03
Signed-off-by: Neale Ranns <nranns@cisco.com>

6 files changed, 771 insertions, 0 deletions

diff --git a/src/plugins/l2e/l2e.api b/src/plugins/l2e/l2e.api
new file mode 100644
index 00000000000..172ed48a22b
--- /dev/null
+++ b/src/plugins/l2e/l2e.api
@@ -0,0 +1,38 @@
+/* Hey Emacs use -*- mode: C -*- */
+/*
+ * 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.
+ */
+
+vl_api_version 1.0.0
+
+/** \brief L2 emulation at L3
+    @param client_index - opaque cookie to identify the sender
+    @param context - sender context, to match reply w/ request
+    @param sw_if_index - interface the operation is applied to
+    @param enable - Turn the service on or off
+*/
+autoreply define l2_emulation
+{
+  u32 client_index;
+  u32 context;
+  u32 sw_if_index;
+  u32 ip_table_id;
+  u8  enable;
+};
+
+/*
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/l2e/l2e.c b/src/plugins/l2e/l2e.c
new file mode 100644
index 00000000000..633d1f92838
--- /dev/null
+++ b/src/plugins/l2e/l2e.c
@@ -0,0 +1,485 @@
+/*
+ * l2_emulation.h : Extract L3 packets from the L2 input and feed
+ *                   them into the L3 path.
+ *
+ * Copyright (c) 2013 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 <plugins/l2e/l2e.h>
+#include <vnet/l2/l2_input.h>
+
+/**
+ * Grouping of global data for the L2 emulation feature
+ */
+typedef struct l2_emulation_main_t_
+{
+  /**
+   * Next nodes for L2 output features
+   */
+  u32 l2_input_feat_next[32];
+} l2_emulation_main_t;
+
+static l2_emulation_main_t l2_emulation_main;
+
+/**
+ * Per-interface L2 configuration
+ */
+typedef struct l2_emulation_t_
+{
+  /**
+   * Enabled or Disabled.
+   *  this is required since one L3 protocl can be enabled, but others not
+   */
+  u8 enabled;
+} l2_emulation_t;
+
+/**
+ * A zero'd out struct we can use in the vec_validate
+ */
+static const l2_emulation_t ezero = { };
+
+/**
+ * Per-interface vector of emulation configs
+ */
+l2_emulation_t *l2_emulations;
+
+void
+l2_emulation_enable (u32 sw_if_index)
+{
+  vec_validate_init_empty (l2_emulations, sw_if_index, ezero);
+
+  l2_emulation_t *l23e = &l2_emulations[sw_if_index];
+
+  l23e->enabled = 1;
+
+  /*
+   * L3 enable the interface - using IP unnumbered from the control
+   * plane may not be possible since there may be no BVI interface
+   * to which to unnumber
+   */
+  ip4_sw_interface_enable_disable (sw_if_index, 1);
+  ip6_sw_interface_enable_disable (sw_if_index, 1);
+
+  l2input_intf_bitmap_enable (sw_if_index, L2INPUT_FEAT_L2_EMULATION, 1);
+}
+
+
+void
+l2_emulation_disable (u32 sw_if_index)
+{
+  if (vec_len (l2_emulations) >= sw_if_index)
+    {
+      l2_emulation_t *l23e = &l2_emulations[sw_if_index];
+      memset (l23e, 0, sizeof (*l23e));
+
+      l2input_intf_bitmap_enable (sw_if_index, L2INPUT_FEAT_L2_EMULATION, 0);
+      ip4_sw_interface_enable_disable (sw_if_index, 0);
+      ip6_sw_interface_enable_disable (sw_if_index, 0);
+    }
+}
+
+static clib_error_t *
+l2_emulation_interface_add_del (vnet_main_t * vnm,
+				u32 sw_if_index, u32 is_add)
+{
+  if (is_add)
+    {
+      vec_validate_init_empty (l2_emulations, sw_if_index, ezero);
+    }
+
+  return (NULL);
+}
+
+VNET_SW_INTERFACE_ADD_DEL_FUNCTION (l2_emulation_interface_add_del);
+
+static clib_error_t *
+l2_emulation_cli (vlib_main_t * vm,
+		  unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  u32 sw_if_index = ~0;
+  u8 enable = 1;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "%U", unformat_vnet_sw_interface,
+		    vnm, &sw_if_index))
+	;
+      else if (unformat (input, "enable"))
+	enable = 1;
+      else if (unformat (input, "disable"))
+	enable = 0;
+      else
+	break;
+    }
+
+  if (~0 == sw_if_index)
+    return clib_error_return (0, "interface must be specified");
+
+  if (enable)
+    l2_emulation_enable (sw_if_index);
+  else
+    l2_emulation_disable (sw_if_index);
+
+  return (NULL);
+}
+
+/*?
+ * Configure l2 emualtion.
+ *  When the interface is in L2 mode, configure the extraction of L3
+ *  packets out of the L2 path and into the L3 path.
+ *
+ * @cliexpar
+ * @cliexstart{set interface l2 input l2-emulation <interface-name> [disable]
+ * @cliexend
+ ?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_emulation_cli_node, static) = {
+  .path = "set interface l2 l2-emulation",
+  .short_help =
+  "set interface l2 l2-emulation <interface-name> [disable|enable]\n",
+  .function = l2_emulation_cli,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+l2_emulation_show (vlib_main_t * vm,
+		   unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  l2_emulation_t *l23e;
+  u32 sw_if_index;
+
+  vec_foreach_index (sw_if_index, l2_emulations)
+  {
+    l23e = &l2_emulations[sw_if_index];
+    if (l23e->enabled)
+      {
+	vlib_cli_output (vm, "%U\n",
+			 format_vnet_sw_if_index_name, vnm, sw_if_index);
+      }
+  }
+  return (NULL);
+}
+
+/*?
+ * Show l2 emulation.
+ *  When the interface is in L2 mode, configure the extraction of L3
+ *  packets out of the L2 path and into the L3 path.
+ *
+ * @cliexpar
+ * @cliexstart{show interface l2 l2-emulation
+ * @cliexend
+ ?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_emulation_show_node, static) = {
+  .path = "show interface l2 l2-emulation",
+  .short_help = "show interface l2 l2-emulation\n",
+  .function = l2_emulation_show,
+};
+/* *INDENT-ON* */
+
+#define foreach_l2_emulation                    \
+  _(IP4, "Extract IPv4")                        \
+  _(IP6, "Extract IPv6")
+
+typedef enum
+{
+#define _(sym,str) L2_EMULATION_ERROR_##sym,
+  foreach_l2_emulation
+#undef _
+    L2_EMULATION_N_ERROR,
+} l2_emulation_error_t;
+
+static char *l2_emulation_error_strings[] = {
+#define _(sym,string) string,
+  foreach_l2_emulation
+#undef _
+};
+
+typedef enum
+{
+#define _(sym,str) L2_EMULATION_NEXT_##sym,
+  foreach_l2_emulation
+#undef _
+    L2_EMULATION_N_NEXT,
+} l2_emulation_next_t;
+
+/**
+ * per-packet trace data
+ */
+typedef struct l2_emulation_trace_t_
+{
+  /* per-pkt trace data */
+  u8 extracted;
+} l2_emulation_trace_t;
+
+static uword
+l2_emulation_node_fn (vlib_main_t * vm,
+		      vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  l2_emulation_main_t *em = &l2_emulation_main;
+  u32 n_left_from, *from, *to_next;
+  l2_emulation_next_t next_index;
+  u32 ip4_hits = 0;
+  u32 ip6_hits = 0;
+
+  next_index = 0;
+  n_left_from = frame->n_vectors;
+  from = vlib_frame_vector_args (frame);
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+      while (n_left_from >= 4 && n_left_to_next >= 2)
+	{
+	  vlib_buffer_t *b0, *b1;
+	  u32 sw_if_index0, sw_if_index1;
+	  u16 ether_type0, ether_type1;
+	  u32 next0 = ~0, next1 = ~0;
+	  u8 l2_len0, l2_len1;
+	  u32 bi0, bi1;
+	  u8 *h0, *h1;
+
+	  bi0 = to_next[0] = from[0];
+	  bi1 = to_next[1] = from[1];
+
+	  from += 2;
+	  n_left_from -= 2;
+	  to_next += 2;
+	  n_left_to_next -= 2;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+	  l2_len0 = vnet_buffer (b0)->l2.l2_len;
+	  l2_len1 = vnet_buffer (b1)->l2.l2_len;
+
+	  h0 = vlib_buffer_get_current (b0);
+	  h1 = vlib_buffer_get_current (b1);
+
+	  ether_type0 = clib_net_to_host_u16 (*(u16 *) (h0 + l2_len0 - 2));
+	  ether_type1 = clib_net_to_host_u16 (*(u16 *) (h1 + l2_len1 - 2));
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+	  sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
+
+	  /*
+	   * only extract unicast
+	   */
+	  if (PREDICT_TRUE (!(h0[0] & 0x1)))
+	    {
+	      switch (ether_type0)
+		{
+		case ETHERNET_TYPE_IP4:
+		  ASSERT (l2_emulations[sw_if_index0].enabled);
+		  ++ip4_hits;
+		  next0 = L2_EMULATION_NEXT_IP4;
+		  vlib_buffer_advance (b0, l2_len0);
+		  break;
+		case ETHERNET_TYPE_IP6:
+		  ASSERT (l2_emulations[sw_if_index0].enabled);
+		  ++ip6_hits;
+		  next0 = L2_EMULATION_NEXT_IP6;
+		  vlib_buffer_advance (b0, l2_len0);
+		default:
+		  break;
+		}
+	    }
+	  if (PREDICT_TRUE (!(h1[0] & 0x1)))
+	    {
+	      switch (ether_type1)
+		{
+		case ETHERNET_TYPE_IP4:
+		  ASSERT (l2_emulations[sw_if_index1].enabled);
+		  ++ip4_hits;
+		  next1 = L2_EMULATION_NEXT_IP4;
+		  vlib_buffer_advance (b1, l2_len1);
+		  break;
+		case ETHERNET_TYPE_IP6:
+		  ASSERT (l2_emulations[sw_if_index1].enabled);
+		  ++ip6_hits;
+		  next1 = L2_EMULATION_NEXT_IP6;
+		  vlib_buffer_advance (b1, l2_len1);
+		default:
+		  break;
+		}
+	    }
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
+			     && (b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      l2_emulation_trace_t *t =
+		vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->extracted = (next0 != ~0);
+	    }
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
+			     && (b1->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      l2_emulation_trace_t *t =
+		vlib_add_trace (vm, node, b1, sizeof (*t));
+	      t->extracted = (next1 != ~0);
+	    }
+
+	  /* Determine the next node and remove ourself from bitmap */
+	  if (PREDICT_TRUE (next0 == ~0))
+	    next0 = vnet_l2_feature_next (b0, em->l2_input_feat_next,
+					  L2INPUT_FEAT_L2_EMULATION);
+
+	  /* Determine the next node and remove ourself from bitmap */
+	  if (PREDICT_TRUE (next1 == ~0))
+	    next1 = vnet_l2_feature_next (b1, em->l2_input_feat_next,
+					  L2INPUT_FEAT_L2_EMULATION);
+
+	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
+					   to_next, n_left_to_next,
+					   bi0, bi1, next0, next1);
+	}
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  vlib_buffer_t *b0;
+	  u32 sw_if_index0;
+	  u16 ether_type0;
+	  u32 next0 = ~0;
+	  u8 l2_len0;
+	  u32 bi0;
+	  u8 *h0;
+
+	  bi0 = from[0];
+	  to_next[0] = bi0;
+	  from += 1;
+	  to_next += 1;
+	  n_left_from -= 1;
+	  n_left_to_next -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  l2_len0 = vnet_buffer (b0)->l2.l2_len;
+
+	  h0 = vlib_buffer_get_current (b0);
+	  ether_type0 = clib_net_to_host_u16 (*(u16 *) (h0 + l2_len0 - 2));
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+
+	  /*
+	   * only extract unicast
+	   */
+	  if (PREDICT_TRUE (!(h0[0] & 0x1)))
+	    {
+	      switch (ether_type0)
+		{
+		case ETHERNET_TYPE_IP4:
+		  ASSERT (l2_emulations[sw_if_index0].enabled);
+		  ++ip4_hits;
+		  next0 = L2_EMULATION_NEXT_IP4;
+		  vlib_buffer_advance (b0, l2_len0);
+		  break;
+		case ETHERNET_TYPE_IP6:
+		  ASSERT (l2_emulations[sw_if_index0].enabled);
+		  ++ip6_hits;
+		  next0 = L2_EMULATION_NEXT_IP6;
+		  vlib_buffer_advance (b0, l2_len0);
+		default:
+		  break;
+		}
+	    }
+
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
+			     && (b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      l2_emulation_trace_t *t =
+		vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->extracted = (next0 != ~0);
+	    }
+
+	  /* Determine the next node and remove ourself from bitmap */
+	  if (PREDICT_TRUE (next0 == ~0))
+	    next0 = vnet_l2_feature_next (b0, em->l2_input_feat_next,
+					  L2INPUT_FEAT_L2_EMULATION);
+
+	  /* verify speculative enqueue, maybe switch current next frame */
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+					   to_next, n_left_to_next,
+					   bi0, next0);
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  vlib_node_increment_counter (vm, node->node_index,
+			       L2_EMULATION_ERROR_IP4, ip4_hits);
+  vlib_node_increment_counter (vm, node->node_index,
+			       L2_EMULATION_ERROR_IP6, ip6_hits);
+
+  return frame->n_vectors;
+}
+
+/* packet trace format function */
+static u8 *
+format_l2_emulation_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  l2_emulation_trace_t *t = va_arg (*args, l2_emulation_trace_t *);
+
+  s = format (s, "l2-emulation: %s", (t->extracted ? "yes" : "no"));
+
+  return s;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (l2_emulation_node) = {
+  .function = l2_emulation_node_fn,
+  .name = "l2-emulation",
+  .vector_size = sizeof (u32),
+  .format_trace = format_l2_emulation_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+
+  .n_errors = ARRAY_LEN(l2_emulation_error_strings),
+  .error_strings = l2_emulation_error_strings,
+
+  .n_next_nodes = L2_EMULATION_N_NEXT,
+
+  /* edit / add dispositions here */
+  .next_nodes = {
+    [L2_EMULATION_NEXT_IP4] = "ip4-input",
+    [L2_EMULATION_NEXT_IP6] = "ip6-input",
+  },
+};
+/* *INDENT-ON* */
+
+VLIB_NODE_FUNCTION_MULTIARCH (l2_emulation_node, l2_emulation_node_fn);
+
+
+static clib_error_t *
+l2_emulation_init (vlib_main_t * vm)
+{
+  l2_emulation_main_t *em = &l2_emulation_main;
+
+  /* Initialize the feature next-node indexes */
+  feat_bitmap_init_next_nodes (vm,
+			       l2_emulation_node.index,
+			       L2INPUT_N_FEAT,
+			       l2input_get_feat_names (),
+			       em->l2_input_feat_next);
+
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (l2_emulation_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/l2e/l2e.h b/src/plugins/l2e/l2e.h
new file mode 100644
index 00000000000..954950149f9
--- /dev/null
+++ b/src/plugins/l2e/l2e.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2013 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.
+ */
+
+#ifndef included_vnet_l2_emulation_h
+#define included_vnet_l2_emulation_h
+
+#include <vlib/vlib.h>
+#include <vnet/vnet.h>
+
+/**
+ * L2 Emulation is a feautre that is applied to L2 ports to 'extract'
+ * IP packets from the L2 path and inject them into the L3 path (i.e.
+ * into the appropriate ip[4|6]_input node).
+ * L3 routes in the table_id for that interface should then be configured
+ * as DVR routes, therefore the forwarded packet has the L2 header
+ * preserved and togehter the L3 routed system behaves like an L2 bridge.
+ */
+extern void l2_emulation_enable (u32 sw_if_index);
+extern void l2_emulation_disable (u32 sw_if_index);
+
+#endif
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/l2e/l2e_all_api_h.h b/src/plugins/l2e/l2e_all_api_h.h
new file mode 100644
index 00000000000..44fad6bf64e
--- /dev/null
+++ b/src/plugins/l2e/l2e_all_api_h.h
@@ -0,0 +1,17 @@
+/*
+ * 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 the generated file, see BUILT_SOURCES in Makefile.am */
+#include <l2e/l2e.api.h>
+
diff --git a/src/plugins/l2e/l2e_api.c b/src/plugins/l2e/l2e_api.c
new file mode 100644
index 00000000000..470427e8952
--- /dev/null
+++ b/src/plugins/l2e/l2e_api.c
@@ -0,0 +1,162 @@
+/*
+ *------------------------------------------------------------------
+ * l2e_api.c - layer 2 emulation api
+ *
+ * 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 <vnet/vnet.h>
+#include <vnet/plugin/plugin.h>
+
+#include <vnet/interface.h>
+#include <vnet/api_errno.h>
+#include <vpp/app/version.h>
+
+#include <l2e/l2e.h>
+
+#include <vlibapi/api.h>
+#include <vlibmemory/api.h>
+
+/* define message IDs */
+#include <l2e/l2e_msg_enum.h>
+
+#define vl_typedefs		/* define message structures */
+#include <l2e/l2e_all_api_h.h>
+#undef vl_typedefs
+
+#define vl_endianfun		/* define message structures */
+#include <l2e/l2e_all_api_h.h>
+#undef vl_endianfun
+
+/* instantiate all the print functions we know about */
+#define vl_print(handle, ...) vlib_cli_output (handle, __VA_ARGS__)
+#define vl_printfun
+#include <l2e/l2e_all_api_h.h>
+#undef vl_printfun
+
+/* Get the API version number */
+#define vl_api_version(n,v) static u32 api_version=(v);
+#include <acl/acl_all_api_h.h>
+#undef vl_api_version
+
+#include <vlibapi/api_helper_macros.h>
+
+#define foreach_l2e_api_msg                                 \
+_(L2_EMULATION, l2_emulation)
+
+/**
+ * L2 Emulation Main
+ */
+typedef struct l2_emulation_main_t_
+{
+  u16 msg_id_base;
+} l2_emulation_main_t;
+
+static l2_emulation_main_t l2_emulation_main;
+
+#define L2E_MSG_BASE l2_emulation_main.msg_id_base
+
+static void
+vl_api_l2_emulation_t_handler (vl_api_l2_emulation_t * mp)
+{
+  vl_api_l2_emulation_reply_t *rmp;
+  int rv = 0;
+
+  VALIDATE_SW_IF_INDEX (mp);
+
+  u32 sw_if_index = ntohl (mp->sw_if_index);
+
+  if (mp->enable)
+    l2_emulation_enable (sw_if_index);
+  else
+    l2_emulation_disable (sw_if_index);
+
+  BAD_SW_IF_INDEX_LABEL;
+
+  REPLY_MACRO (VL_API_L2_EMULATION_REPLY + L2E_MSG_BASE);
+}
+
+/*
+ * l2_api_hookup
+ * Add vpe's API message handlers to the table.
+ * vlib has alread mapped shared memory and
+ * added the client registration handlers.
+ * See .../vlib-api/vlibmemory/memclnt_vlib.c:memclnt_process()
+ */
+#define vl_msg_name_crc_list
+#include <l2e/l2e_all_api_h.h>
+#undef vl_msg_name_crc_list
+
+static void
+setup_message_id_table (api_main_t * am)
+{
+#define _(id,n,crc)                                     \
+  vl_msg_api_add_msg_name_crc (am, #n "_" #crc, id + L2E_MSG_BASE);
+  foreach_vl_msg_name_crc_l2e;
+#undef _
+}
+
+static void
+l2e_api_hookup (vlib_main_t * vm)
+{
+#define _(N,n)                                                  \
+    vl_msg_api_set_handlers(VL_API_##N + L2E_MSG_BASE,          \
+                            #n,                                 \
+                            vl_api_##n##_t_handler,             \
+                            vl_noop_handler,                    \
+                            vl_api_##n##_t_endian,              \
+                            vl_api_##n##_t_print,               \
+                            sizeof(vl_api_##n##_t), 1);
+  foreach_l2e_api_msg;
+#undef _
+}
+
+static clib_error_t *
+l2e_init (vlib_main_t * vm)
+{
+  api_main_t *am = &api_main;
+  l2_emulation_main_t *l2em = &l2_emulation_main;
+  u8 *name = format (0, "l2e_%08x%c", api_version, 0);
+
+  /* Ask for a correctly-sized block of API message decode slots */
+  l2em->msg_id_base = vl_msg_api_get_msg_ids ((char *) name,
+					      VL_MSG_FIRST_AVAILABLE);
+
+  l2e_api_hookup (vm);
+
+  /* Add our API messages to the global name_crc hash table */
+  setup_message_id_table (am);
+
+  vec_free (name);
+  return (NULL);
+}
+
+VLIB_API_INIT_FUNCTION (l2e_init);
+
+/* *INDENT-OFF* */
+VLIB_PLUGIN_REGISTER () = {
+    .version = VPP_BUILD_VER,
+    .description = "L2 Emulation",
+};
+/* *INDENT-ON* */
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/l2e/l2e_msg_enum.h b/src/plugins/l2e/l2e_msg_enum.h
new file mode 100644
index 00000000000..85c8328c703
--- /dev/null
+++ b/src/plugins/l2e/l2e_msg_enum.h
@@ -0,0 +1,28 @@
+/*
+ * 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.
+ */
+#ifndef included_l2e_msg_enum_h
+#define included_l2e_msg_enum_h
+
+#include <vppinfra/byte_order.h>
+
+#define vl_msg_id(n,h) n,
+typedef enum {
+#include <l2e/l2e_all_api_h.h>
+    /* We'll want to know how many messages IDs we need... */
+    VL_MSG_FIRST_AVAILABLE,
+} vl_msg_id_t;
+#undef vl_msg_id
+
+#endif