Reorganize source tree to use single autotools instance

Change-Id: I7b51f88292e057c6443b12224486f2d0c9f8ae23
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 719 insertions, 0 deletions

diff --git a/src/vnet/l2/l2_rw.c b/src/vnet/l2/l2_rw.c
new file mode 100644
index 00000000000..c54509d048b
--- /dev/null
+++ b/src/vnet/l2/l2_rw.c
@@ -0,0 +1,719 @@
+/*
+ * Copyright (c) 2015 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 <vlib/vlib.h>
+#include <vnet/l2/feat_bitmap.h>
+#include <vnet/l2/l2_rw.h>
+
+/**
+ * @file
+ * @brief Layer 2 Rewrite.
+ *
+ * Layer 2-Rewrite node uses classify tables to match packets. Then, using
+ * the provisioned mask and value, modfies the packet header.
+ */
+
+
+l2_rw_main_t l2_rw_main;
+
+vlib_node_registration_t l2_rw_node;
+
+typedef struct
+{
+  u32 sw_if_index;
+  u32 classify_table_index;
+  u32 rewrite_entry_index;
+} l2_rw_trace_t;
+
+static u8 *
+format_l2_rw_entry (u8 * s, va_list * args)
+{
+  l2_rw_entry_t *e = va_arg (*args, l2_rw_entry_t *);
+  l2_rw_main_t *rw = &l2_rw_main;
+  s = format (s, "%d -  mask:%U value:%U\n",
+	      e - rw->entries,
+	      format_hex_bytes, e->mask,
+	      e->rewrite_n_vectors * sizeof (u32x4), format_hex_bytes,
+	      e->value, e->rewrite_n_vectors * sizeof (u32x4));
+  s =
+    format (s, "      hits:%d skip_bytes:%d", e->hit_count,
+	    e->skip_n_vectors * sizeof (u32x4));
+  return s;
+}
+
+static u8 *
+format_l2_rw_config (u8 * s, va_list * args)
+{
+  l2_rw_config_t *c = va_arg (*args, l2_rw_config_t *);
+  return format (s, "table-index:%d miss-index:%d",
+		 c->table_index, c->miss_index);
+}
+
+/* packet trace format function */
+static u8 *
+format_l2_rw_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_rw_trace_t *t = va_arg (*args, l2_rw_trace_t *);
+  return format (s, "l2-rw: sw_if_index %d, table %d, entry %d",
+		 t->sw_if_index, t->classify_table_index,
+		 t->rewrite_entry_index);
+}
+
+always_inline l2_rw_config_t *
+l2_rw_get_config (u32 sw_if_index)
+{
+  l2_rw_main_t *rw = &l2_rw_main;
+  if (PREDICT_FALSE (!clib_bitmap_get (rw->configs_bitmap, sw_if_index)))
+    {
+      vec_validate (rw->configs, sw_if_index);
+      rw->configs[sw_if_index].table_index = ~0;
+      rw->configs[sw_if_index].miss_index = ~0;
+      rw->configs_bitmap =
+	clib_bitmap_set (rw->configs_bitmap, sw_if_index, 1);
+    }
+  return &rw->configs[sw_if_index];
+}
+
+static_always_inline void
+l2_rw_rewrite (l2_rw_entry_t * rwe, u8 * h)
+{
+  if (U32X4_ALIGNED (h))
+    {
+      u32x4 *d = ((u32x4 *) h) + rwe->skip_n_vectors;
+      switch (rwe->rewrite_n_vectors)
+	{
+	case 5:
+	  d[4] = (d[4] & ~rwe->mask[4]) | rwe->value[4];
+	  /* FALLTHROUGH */
+	case 4:
+	  d[3] = (d[3] & ~rwe->mask[3]) | rwe->value[3];
+	  /* FALLTHROUGH */
+	case 3:
+	  d[2] = (d[2] & ~rwe->mask[2]) | rwe->value[2];
+	  /* FALLTHROUGH */
+	case 2:
+	  d[1] = (d[1] & ~rwe->mask[1]) | rwe->value[1];
+	  /* FALLTHROUGH */
+	case 1:
+	  d[0] = (d[0] & ~rwe->mask[0]) | rwe->value[0];
+	  break;
+	default:
+	  abort ();
+	}
+    }
+  else
+    {
+      u64 *d = ((u64 *) h) + rwe->skip_n_vectors * 2;
+      switch (rwe->rewrite_n_vectors)
+	{
+	case 5:
+	  d[8] =
+	    (d[8] & ~(((u64 *) rwe->mask)[8])) | (((u64 *) rwe->value)[8]);
+	  d[9] =
+	    (d[9] & ~(((u64 *) rwe->mask)[9])) | (((u64 *) rwe->value)[9]);
+	  /* FALLTHROUGH */
+	case 4:
+	  d[6] =
+	    (d[6] & ~(((u64 *) rwe->mask)[6])) | (((u64 *) rwe->value)[6]);
+	  d[7] =
+	    (d[7] & ~(((u64 *) rwe->mask)[7])) | (((u64 *) rwe->value)[7]);
+	  /* FALLTHROUGH */
+	case 3:
+	  d[4] =
+	    (d[4] & ~(((u64 *) rwe->mask)[4])) | (((u64 *) rwe->value)[4]);
+	  d[5] =
+	    (d[5] & ~(((u64 *) rwe->mask)[5])) | (((u64 *) rwe->value)[5]);
+	  /* FALLTHROUGH */
+	case 2:
+	  d[2] =
+	    (d[2] & ~(((u64 *) rwe->mask)[2])) | (((u64 *) rwe->value)[2]);
+	  d[3] =
+	    (d[3] & ~(((u64 *) rwe->mask)[3])) | (((u64 *) rwe->value)[3]);
+	  /* FALLTHROUGH */
+	case 1:
+	  d[0] =
+	    (d[0] & ~(((u64 *) rwe->mask)[0])) | (((u64 *) rwe->value)[0]);
+	  d[1] =
+	    (d[1] & ~(((u64 *) rwe->mask)[1])) | (((u64 *) rwe->value)[1]);
+	  break;
+	default:
+	  abort ();
+	}
+    }
+}
+
+static uword
+l2_rw_node_fn (vlib_main_t * vm,
+	       vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  l2_rw_main_t *rw = &l2_rw_main;
+  u32 n_left_from, *from, *to_next, next_index;
+  vnet_classify_main_t *vcm = &vnet_classify_main;
+  f64 now = vlib_time_now (vlib_get_main ());
+  u32 prefetch_size = 0;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;	/* number of packets to process */
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      /* get space to enqueue frame to graph node "next_index" */
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      while (n_left_from >= 4 && n_left_to_next >= 2)
+	{
+	  u32 bi0, next0, sw_if_index0, feature_bitmap0, rwe_index0;
+	  u32 bi1, next1, sw_if_index1, feature_bitmap1, rwe_index1;
+	  vlib_buffer_t *b0, *b1;
+	  ethernet_header_t *h0, *h1;
+	  l2_rw_config_t *config0, *config1;
+	  u64 hash0, hash1;
+	  vnet_classify_table_t *t0, *t1;
+	  vnet_classify_entry_t *e0, *e1;
+	  l2_rw_entry_t *rwe0, *rwe1;
+
+	  {
+	    vlib_buffer_t *p2, *p3;
+	    p2 = vlib_get_buffer (vm, from[2]);
+	    p3 = vlib_get_buffer (vm, from[3]);
+
+	    vlib_prefetch_buffer_header (p2, LOAD);
+	    vlib_prefetch_buffer_header (p3, LOAD);
+	    CLIB_PREFETCH (vlib_buffer_get_current (p2), prefetch_size, LOAD);
+	    CLIB_PREFETCH (vlib_buffer_get_current (p3), prefetch_size, LOAD);
+	  }
+
+	  bi0 = from[0];
+	  bi1 = from[1];
+	  to_next[0] = bi0;
+	  to_next[1] = bi1;
+	  from += 2;
+	  to_next += 2;
+	  n_left_from -= 2;
+	  n_left_to_next -= 2;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+	  h0 = vlib_buffer_get_current (b0);
+	  h1 = vlib_buffer_get_current (b1);
+
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+	  sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
+	  config0 = l2_rw_get_config (sw_if_index0);	/*TODO: check sw_if_index0 value */
+	  config1 = l2_rw_get_config (sw_if_index1);	/*TODO: check sw_if_index0 value */
+	  t0 = pool_elt_at_index (vcm->tables, config0->table_index);
+	  t1 = pool_elt_at_index (vcm->tables, config1->table_index);
+	  prefetch_size =
+	    (t1->skip_n_vectors + t1->match_n_vectors) * sizeof (u32x4);
+
+	  hash0 = vnet_classify_hash_packet (t0, (u8 *) h0);
+	  hash1 = vnet_classify_hash_packet (t1, (u8 *) h1);
+	  e0 = vnet_classify_find_entry (t0, (u8 *) h0, hash0, now);
+	  e1 = vnet_classify_find_entry (t1, (u8 *) h1, hash1, now);
+
+	  while (!e0 && (t0->next_table_index != ~0))
+	    {
+	      t0 = pool_elt_at_index (vcm->tables, t0->next_table_index);
+	      hash0 = vnet_classify_hash_packet (t0, (u8 *) h0);
+	      e0 = vnet_classify_find_entry (t0, (u8 *) h0, hash0, now);
+	    }
+
+	  while (!e1 && (t1->next_table_index != ~0))
+	    {
+	      t1 = pool_elt_at_index (vcm->tables, t1->next_table_index);
+	      hash1 = vnet_classify_hash_packet (t1, (u8 *) h1);
+	      e1 = vnet_classify_find_entry (t1, (u8 *) h1, hash1, now);
+	    }
+
+	  rwe_index0 = e0 ? e0->opaque_index : config0->miss_index;
+	  rwe_index1 = e1 ? e1->opaque_index : config1->miss_index;
+
+	  if (rwe_index0 != ~0)
+	    {
+	      rwe0 = pool_elt_at_index (rw->entries, rwe_index0);
+	      l2_rw_rewrite (rwe0, (u8 *) h0);
+	    }
+	  if (rwe_index1 != ~0)
+	    {
+	      rwe1 = pool_elt_at_index (rw->entries, rwe_index1);
+	      l2_rw_rewrite (rwe1, (u8 *) h1);
+	    }
+
+	  if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      l2_rw_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->sw_if_index = sw_if_index0;
+	      t->classify_table_index = config0->table_index;
+	      t->rewrite_entry_index = rwe_index0;
+	    }
+
+	  if (PREDICT_FALSE ((b1->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      l2_rw_trace_t *t = vlib_add_trace (vm, node, b1, sizeof (*t));
+	      t->sw_if_index = sw_if_index1;
+	      t->classify_table_index = config1->table_index;
+	      t->rewrite_entry_index = rwe_index1;
+	    }
+
+	  /* Update feature bitmap and get next feature index */
+	  feature_bitmap0 =
+	    vnet_buffer (b0)->l2.feature_bitmap & ~L2INPUT_FEAT_RW;
+	  feature_bitmap1 =
+	    vnet_buffer (b1)->l2.feature_bitmap & ~L2INPUT_FEAT_RW;
+	  vnet_buffer (b0)->l2.feature_bitmap = feature_bitmap0;
+	  vnet_buffer (b1)->l2.feature_bitmap = feature_bitmap1;
+	  next0 = feat_bitmap_get_next_node_index (rw->feat_next_node_index,
+						   feature_bitmap0);
+	  next1 = feat_bitmap_get_next_node_index (rw->feat_next_node_index,
+						   feature_bitmap1);
+
+	  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)
+	{
+	  u32 bi0, next0, sw_if_index0, feature_bitmap0, rwe_index0;
+	  vlib_buffer_t *b0;
+	  ethernet_header_t *h0;
+	  l2_rw_config_t *config0;
+	  u64 hash0;
+	  vnet_classify_table_t *t0;
+	  vnet_classify_entry_t *e0;
+	  l2_rw_entry_t *rwe0;
+
+	  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);
+	  h0 = vlib_buffer_get_current (b0);
+
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+	  config0 = l2_rw_get_config (sw_if_index0);	/*TODO: check sw_if_index0 value */
+	  t0 = pool_elt_at_index (vcm->tables, config0->table_index);
+
+	  hash0 = vnet_classify_hash_packet (t0, (u8 *) h0);
+	  e0 = vnet_classify_find_entry (t0, (u8 *) h0, hash0, now);
+
+	  while (!e0 && (t0->next_table_index != ~0))
+	    {
+	      t0 = pool_elt_at_index (vcm->tables, t0->next_table_index);
+	      hash0 = vnet_classify_hash_packet (t0, (u8 *) h0);
+	      e0 = vnet_classify_find_entry (t0, (u8 *) h0, hash0, now);
+	    }
+
+	  rwe_index0 = e0 ? e0->opaque_index : config0->miss_index;
+
+	  if (rwe_index0 != ~0)
+	    {
+	      rwe0 = pool_elt_at_index (rw->entries, rwe_index0);
+	      l2_rw_rewrite (rwe0, (u8 *) h0);
+	    }
+
+	  if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      l2_rw_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->sw_if_index = sw_if_index0;
+	      t->classify_table_index = config0->table_index;
+	      t->rewrite_entry_index = rwe_index0;
+	    }
+
+	  /* Update feature bitmap and get next feature index */
+	  feature_bitmap0 =
+	    vnet_buffer (b0)->l2.feature_bitmap & ~L2INPUT_FEAT_RW;
+	  vnet_buffer (b0)->l2.feature_bitmap = feature_bitmap0;
+	  next0 = feat_bitmap_get_next_node_index (rw->feat_next_node_index,
+						   feature_bitmap0);
+
+	  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);
+    }
+
+  return frame->n_vectors;
+}
+
+int
+l2_rw_mod_entry (u32 * index,
+		 u8 * mask, u8 * value, u32 len, u32 skip, u8 is_del)
+{
+  l2_rw_main_t *rw = &l2_rw_main;
+  l2_rw_entry_t *e = 0;
+  if (*index != ~0)
+    {
+      if (pool_is_free_index (rw->entries, *index))
+	{
+	  return -1;
+	}
+      e = pool_elt_at_index (rw->entries, *index);
+    }
+  else
+    {
+      pool_get (rw->entries, e);
+      *index = e - rw->entries;
+    }
+
+  if (!e)
+    return -1;
+
+  if (is_del)
+    {
+      pool_put (rw->entries, e);
+      return 0;
+    }
+
+  e->skip_n_vectors = skip / sizeof (u32x4);
+  skip -= e->skip_n_vectors * sizeof (u32x4);
+  e->rewrite_n_vectors = (skip + len - 1) / sizeof (u32x4) + 1;
+  vec_alloc_aligned (e->mask, e->rewrite_n_vectors, sizeof (u32x4));
+  memset (e->mask, 0, e->rewrite_n_vectors * sizeof (u32x4));
+  vec_alloc_aligned (e->value, e->rewrite_n_vectors, sizeof (u32x4));
+  memset (e->value, 0, e->rewrite_n_vectors * sizeof (u32x4));
+
+  clib_memcpy (((u8 *) e->value) + skip, value, len);
+  clib_memcpy (((u8 *) e->mask) + skip, mask, len);
+
+  int i;
+  for (i = 0; i < e->rewrite_n_vectors; i++)
+    {
+      e->value[i] &= e->mask[i];
+    }
+
+  return 0;
+}
+
+static clib_error_t *
+l2_rw_entry_cli_fn (vlib_main_t * vm,
+		    unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  u32 index = ~0;
+  u8 *mask = 0;
+  u8 *value = 0;
+  u32 skip = 0;
+  u8 del = 0;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "index %d", &index))
+	;
+      else if (unformat (input, "mask %U", unformat_hex_string, &mask))
+	;
+      else if (unformat (input, "value %U", unformat_hex_string, &value))
+	;
+      else if (unformat (input, "skip %d", &skip))
+	;
+      else if (unformat (input, "del"))
+	del = 1;
+      else
+	break;
+    }
+
+  if (!mask || !value)
+    return clib_error_return (0, "Unspecified mask or value");
+
+  if (vec_len (mask) != vec_len (value))
+    return clib_error_return (0, "Mask and value lengths must be identical");
+
+  int ret;
+  if ((ret =
+       l2_rw_mod_entry (&index, mask, value, vec_len (mask), skip, del)))
+    return clib_error_return (0, "Could not add entry");
+
+  return 0;
+}
+
+/*?
+ * Layer 2-Rewrite node uses classify tables to match packets. Then, using
+ * the provisioned mask and value, modfies the packet header.
+ *
+ * @cliexpar
+ * @todo This is incomplete. This needs a detailed description and a
+ * practical example.
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_rw_entry_cli, static) = {
+  .path = "l2 rewrite entry",
+  .short_help =
+  "l2 rewrite entry [index <index>] [mask <hex-mask>] [value <hex-value>] [skip <n_bytes>] [del]",
+  .function = l2_rw_entry_cli_fn,
+};
+/* *INDENT-ON* */
+
+int
+l2_rw_interface_set_table (u32 sw_if_index, u32 table_index, u32 miss_index)
+{
+  l2_rw_config_t *c = l2_rw_get_config (sw_if_index);
+  l2_rw_main_t *rw = &l2_rw_main;
+
+  c->table_index = table_index;
+  c->miss_index = miss_index;
+  u32 feature_bitmap = (table_index == ~0) ? 0 : L2INPUT_FEAT_RW;
+
+  l2input_intf_bitmap_enable (sw_if_index, L2INPUT_FEAT_RW, feature_bitmap);
+
+  if (c->table_index == ~0)
+    clib_bitmap_set (rw->configs_bitmap, sw_if_index, 0);
+
+  return 0;
+}
+
+static clib_error_t *
+l2_rw_interface_cli_fn (vlib_main_t * vm,
+			unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  u32 table_index = ~0;
+  u32 sw_if_index = ~0;
+  u32 miss_index = ~0;
+
+  if (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      unformat (input, "%U", unformat_vnet_sw_interface, vnm, &sw_if_index);
+    }
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "table %d", &table_index))
+	;
+      else if (unformat (input, "miss-index %d", &miss_index))
+	;
+      else
+	break;
+    }
+
+  if (sw_if_index == ~0)
+    return clib_error_return (0,
+			      "You must specify an interface 'iface <interface>'",
+			      format_unformat_error, input);
+  int ret;
+  if ((ret =
+       l2_rw_interface_set_table (sw_if_index, table_index, miss_index)))
+    return clib_error_return (0, "l2_rw_interface_set_table returned %d",
+			      ret);
+
+  return 0;
+}
+
+/*?
+ * Layer 2-Rewrite node uses classify tables to match packets. Then, using
+ * the provisioned mask and value, modfies the packet header.
+ *
+ * @cliexpar
+ * @todo This is incomplete. This needs a detailed description and a
+ * practical example.
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_rw_interface_cli, static) = {
+  .path = "set interface l2 rewrite",
+  .short_help =
+  "set interface l2 rewrite <interface> [table <table index>] [miss-index <entry-index>]",
+  .function = l2_rw_interface_cli_fn,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+l2_rw_show_interfaces_cli_fn (vlib_main_t * vm,
+			      unformat_input_t * input,
+			      vlib_cli_command_t * cmd)
+{
+  l2_rw_main_t *rw = &l2_rw_main;
+  if (clib_bitmap_count_set_bits (rw->configs_bitmap) == 0)
+    vlib_cli_output (vm, "No interface is currently using l2 rewrite\n");
+
+  uword i;
+  /* *INDENT-OFF* */
+  clib_bitmap_foreach(i, rw->configs_bitmap, {
+      vlib_cli_output (vm, "sw_if_index:%d %U\n", i, format_l2_rw_config, &rw->configs[i]);
+  });
+  /* *INDENT-ON* */
+  return 0;
+}
+
+/*?
+ * Layer 2-Rewrite node uses classify tables to match packets. Then, using
+ * the provisioned mask and value, modfies the packet header.
+ *
+ * @cliexpar
+ * @todo This is incomplete. This needs a detailed description and a
+ * practical example.
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_rw_show_interfaces_cli, static) = {
+  .path = "show l2 rewrite interfaces",
+  .short_help =
+  "show l2 rewrite interfaces",
+  .function = l2_rw_show_interfaces_cli_fn,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+l2_rw_show_entries_cli_fn (vlib_main_t * vm,
+			   unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  l2_rw_main_t *rw = &l2_rw_main;
+  l2_rw_entry_t *e;
+  if (pool_elts (rw->entries) == 0)
+    vlib_cli_output (vm, "No entries\n");
+
+  /* *INDENT-OFF* */
+  pool_foreach(e, rw->entries, {
+    vlib_cli_output (vm, "%U\n", format_l2_rw_entry, e);
+  });
+  /* *INDENT-ON* */
+  return 0;
+}
+
+/*?
+ * Layer 2-Rewrite node uses classify tables to match packets. Then, using
+ * the provisioned mask and value, modfies the packet header.
+ *
+ * @cliexpar
+ * @todo This is incomplete. This needs a detailed description and a
+ * practical example.
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_rw_show_entries_cli, static) = {
+  .path = "show l2 rewrite entries",
+  .short_help =
+  "show l2 rewrite entries",
+  .function = l2_rw_show_entries_cli_fn,
+};
+/* *INDENT-ON* */
+
+int
+l2_rw_enable_disable (u32 bridge_domain, u8 disable)
+{
+  u32 mask = L2INPUT_FEAT_RW;
+  l2input_set_bridge_features (bridge_domain, mask, disable ? 0 : mask);
+  return 0;
+}
+
+static clib_error_t *
+l2_rw_set_cli_fn (vlib_main_t * vm,
+		  unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  u32 bridge_domain;
+  u8 disable = 0;
+
+  if (unformat_check_input (input) == UNFORMAT_END_OF_INPUT ||
+      !unformat (input, "%d", &bridge_domain))
+    {
+      return clib_error_return (0, "You must specify a bridge domain");
+    }
+
+  if (unformat_check_input (input) != UNFORMAT_END_OF_INPUT &&
+      unformat (input, "disable"))
+    {
+      disable = 1;
+    }
+
+  if (l2_rw_enable_disable (bridge_domain, disable))
+    return clib_error_return (0, "Could not enable or disable rewrite");
+
+  return 0;
+}
+
+/*?
+ * Layer 2-Rewrite node uses classify tables to match packets. Then, using
+ * the provisioned mask and value, modfies the packet header.
+ *
+ * @cliexpar
+ * @todo This is incomplete. This needs a detailed description and a
+ * practical example.
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_rw_set_cli, static) = {
+  .path = "set bridge-domain rewrite",
+  .short_help =
+  "set bridge-domain rewrite <bridge-domain> [disable]",
+  .function = l2_rw_set_cli_fn,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+l2_rw_init (vlib_main_t * vm)
+{
+  l2_rw_main_t *rw = &l2_rw_main;
+  rw->configs = 0;
+  rw->entries = 0;
+  clib_bitmap_alloc (rw->configs_bitmap, 1);
+  feat_bitmap_init_next_nodes (vm,
+			       l2_rw_node.index,
+			       L2INPUT_N_FEAT,
+			       l2input_get_feat_names (),
+			       rw->feat_next_node_index);
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (l2_rw_init);
+
+enum
+{
+  L2_RW_NEXT_DROP,
+  L2_RW_N_NEXT,
+};
+
+#define foreach_l2_rw_error               \
+_(UNKNOWN, "Unknown error")
+
+typedef enum
+{
+#define _(sym,str) L2_RW_ERROR_##sym,
+  foreach_l2_rw_error
+#undef _
+    L2_RW_N_ERROR,
+} l2_rw_error_t;
+
+static char *l2_rw_error_strings[] = {
+#define _(sym,string) string,
+  foreach_l2_rw_error
+#undef _
+};
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (l2_rw_node) = {
+  .function = l2_rw_node_fn,
+  .name = "l2-rw",
+  .vector_size = sizeof (u32),
+  .format_trace = format_l2_rw_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN(l2_rw_error_strings),
+  .error_strings = l2_rw_error_strings,
+  .runtime_data_bytes = 0,
+  .n_next_nodes = L2_RW_N_NEXT,
+  .next_nodes = { [L2_RW_NEXT_DROP]  = "error-drop"},
+};
+/* *INDENT-ON* */
+
+VLIB_NODE_FUNCTION_MULTIARCH (l2_rw_node, l2_rw_node_fn)
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */