Reorganize source tree to use single autotools instance

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

6 files changed, 946 insertions, 0 deletions

diff --git a/src/vnet/hdlc/error.def b/src/vnet/hdlc/error.def
new file mode 100644
index 00000000000..16e001bbcfa
--- /dev/null
+++ b/src/vnet/hdlc/error.def
@@ -0,0 +1,42 @@
+/*
+ * 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.
+ */
+/*
+ * hdlc_error.def: hdlc errors
+ *
+ * Copyright (c) 2008 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+hdlc_error (NONE, "no error")
+hdlc_error (UNKNOWN_PROTOCOL, "unknown hdlc protocol")
+hdlc_error (UNKNOWN_ADDRESS_CONTROL, "address, control != 0x0f00")
diff --git a/src/vnet/hdlc/hdlc.c b/src/vnet/hdlc/hdlc.c
new file mode 100644
index 00000000000..174085ac519
--- /dev/null
+++ b/src/vnet/hdlc/hdlc.c
@@ -0,0 +1,249 @@
+/*
+ * 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.
+ */
+/*
+ * hdlc.c: hdlc
+ *
+ * Copyright (c) 2010 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <vnet/vnet.h>
+#include <vnet/hdlc/hdlc.h>
+
+/* Global main structure. */
+hdlc_main_t hdlc_main;
+
+u8 * format_hdlc_protocol (u8 * s, va_list * args)
+{
+  hdlc_protocol_t p = va_arg (*args, u32);
+  hdlc_main_t * pm = &hdlc_main;
+  hdlc_protocol_info_t * pi = hdlc_get_protocol_info (pm, p);
+
+  if (pi)
+    s = format (s, "%s", pi->name);
+  else
+    s = format (s, "0x%04x", p);
+
+  return s;
+}
+
+u8 * format_hdlc_header_with_length (u8 * s, va_list * args)
+{
+  hdlc_main_t * pm = &hdlc_main;
+  hdlc_header_t * h = va_arg (*args, hdlc_header_t *);
+  u32 max_header_bytes = va_arg (*args, u32);
+  hdlc_protocol_t p = clib_net_to_host_u16 (h->protocol);
+  uword indent, header_bytes;
+
+  header_bytes = sizeof (h[0]);
+  if (max_header_bytes != 0 && header_bytes > max_header_bytes)
+    return format (s, "hdlc header truncated");
+
+  indent = format_get_indent (s);
+
+  s = format (s, "HDLC %U", format_hdlc_protocol, p);
+
+  if (h->address != 0xff)
+    s = format (s, ", address 0x%02x", h->address);
+  if (h->control != 0x03)
+    s = format (s, ", control 0x%02x", h->control);
+
+  if (max_header_bytes != 0 && header_bytes > max_header_bytes)
+    {
+      hdlc_protocol_info_t * pi = hdlc_get_protocol_info (pm, p);
+      vlib_node_t * node = vlib_get_node (pm->vlib_main, pi->node_index);
+      if (node->format_buffer)
+	s = format (s, "\n%U%U",
+		    format_white_space, indent,
+		    node->format_buffer, (void *) (h + 1),
+		    max_header_bytes - header_bytes);
+    }
+
+  return s;
+}
+
+u8 * format_hdlc_header (u8 * s, va_list * args)
+{
+  hdlc_header_t * h = va_arg (*args, hdlc_header_t *);
+  return format (s, "%U", format_hdlc_header_with_length, h, 0);
+}
+
+/* Returns hdlc protocol as an int in host byte order. */
+uword
+unformat_hdlc_protocol_host_byte_order (unformat_input_t * input,
+				       va_list * args)
+{
+  u16 * result = va_arg (*args, u16 *);
+  hdlc_main_t * pm = &hdlc_main;
+  int p, i;
+
+  /* Numeric type. */
+  if (unformat (input, "0x%x", &p)
+      || unformat (input, "%d", &p))
+    {
+      if (p >= (1 << 16))
+	return 0;
+      *result = p;
+      return 1;
+    }
+
+  /* Named type. */
+  if (unformat_user (input, unformat_vlib_number_by_name,
+		     pm->protocol_info_by_name, &i))
+    {
+      hdlc_protocol_info_t * pi = vec_elt_at_index (pm->protocol_infos, i);
+      *result = pi->protocol;
+      return 1;
+    }
+
+  return 0;
+}
+
+uword
+unformat_hdlc_protocol_net_byte_order (unformat_input_t * input,
+				      va_list * args)
+{
+  u16 * result = va_arg (*args, u16 *);
+  if (! unformat_user (input, unformat_hdlc_protocol_host_byte_order, result))
+    return 0;
+  *result = clib_host_to_net_u16 ((u16) *result);
+  return 1;
+}
+
+uword
+unformat_hdlc_header (unformat_input_t * input, va_list * args)
+{
+  u8 ** result = va_arg (*args, u8 **);
+  hdlc_header_t _h, * h = &_h;
+  u16 p;
+
+  if (! unformat (input, "%U",
+		  unformat_hdlc_protocol_host_byte_order, &p))
+    return 0;
+
+  h->address = 0xff;
+  h->control = 0x03;
+  h->protocol = clib_host_to_net_u16 (p);
+
+  /* Add header to result. */
+  {
+    void * p;
+    u32 n_bytes = sizeof (h[0]);
+
+    vec_add2 (*result, p, n_bytes);
+    clib_memcpy (p, h, n_bytes);
+  }
+  
+  return 1;
+}
+
+static u8*
+hdlc_build_rewrite (vnet_main_t * vnm,
+		    u32 sw_if_index,
+		    vnet_link_t link_type,
+		    const void *dst_address)
+{
+  hdlc_header_t * h;
+  u8* rewrite = NULL;
+  hdlc_protocol_t protocol;
+
+  switch (link_type) {
+#define _(a,b) case VNET_LINK_##a: protocol = HDLC_PROTOCOL_##b; break
+    _ (IP4, ip4);
+    _ (IP6, ip6);
+    _ (MPLS, mpls_unicast);
+#undef _
+  default:
+      return (NULL);
+  }
+
+  vec_validate(rewrite, sizeof(*h)-1);
+  h = (hdlc_header_t *)rewrite;
+  h->address = 0x0f;
+  h->control = 0x00;
+  h->protocol = clib_host_to_net_u16 (protocol);
+		     
+  return (rewrite);
+}
+
+VNET_HW_INTERFACE_CLASS (hdlc_hw_interface_class) = {
+  .name = "HDLC",
+  .format_header = format_hdlc_header_with_length,
+  .unformat_header = unformat_hdlc_header,
+  .build_rewrite = hdlc_build_rewrite,
+  .flags = VNET_HW_INTERFACE_CLASS_FLAG_P2P,
+};
+
+static void add_protocol (hdlc_main_t * pm,
+			  hdlc_protocol_t protocol,
+			  char * protocol_name)
+{
+  hdlc_protocol_info_t * pi;
+  u32 i;
+
+  vec_add2 (pm->protocol_infos, pi, 1);
+  i = pi - pm->protocol_infos;
+
+  pi->name = protocol_name;
+  pi->protocol = protocol;
+  pi->next_index = pi->node_index = ~0;
+
+  hash_set (pm->protocol_info_by_protocol, protocol, i);
+  hash_set_mem (pm->protocol_info_by_name, pi->name, i);
+}
+
+static clib_error_t * hdlc_init (vlib_main_t * vm)
+{
+  hdlc_main_t * pm = &hdlc_main;
+
+  memset (pm, 0, sizeof (pm[0]));
+  pm->vlib_main = vm;
+
+  pm->protocol_info_by_name = hash_create_string (0, sizeof (uword));
+  pm->protocol_info_by_protocol = hash_create (0, sizeof (uword));
+
+#define _(n,s) add_protocol (pm, HDLC_PROTOCOL_##s, #s);
+  foreach_hdlc_protocol
+#undef _
+
+  return vlib_call_init_function (vm, hdlc_input_init);
+}
+
+VLIB_INIT_FUNCTION (hdlc_init);
+
+hdlc_main_t * hdlc_get_main (vlib_main_t * vm)
+{
+  vlib_call_init_function (vm, hdlc_init);
+  return &hdlc_main;
+}
+
diff --git a/src/vnet/hdlc/hdlc.h b/src/vnet/hdlc/hdlc.h
new file mode 100644
index 00000000000..73b15c2fac7
--- /dev/null
+++ b/src/vnet/hdlc/hdlc.h
@@ -0,0 +1,127 @@
+/*
+ * 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.
+ */
+/*
+ * hdlc.h: types/functions for hdlc.
+ *
+ * Copyright (c) 2008 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef included_hdlc_h
+#define included_hdlc_h
+
+#include <vnet/vnet.h>
+#include <vnet/hdlc/packet.h>
+#include <vnet/pg/pg.h>
+
+extern vnet_hw_interface_class_t hdlc_hw_interface_class;
+
+typedef enum {
+#define hdlc_error(n,s) HDLC_ERROR_##n,
+#include <vnet/hdlc/error.def>
+#undef hdlc_error
+  HDLC_N_ERROR,
+} hdlc_error_t;
+
+typedef struct {
+  /* Name (a c string). */
+  char * name;
+
+  /* HDLC protocol type in host byte order. */
+  hdlc_protocol_t protocol;
+
+  /* Node which handles this type. */
+  u32 node_index;
+
+  /* Next index for this type. */
+  u32 next_index;
+} hdlc_protocol_info_t;
+
+typedef struct {
+  vlib_main_t * vlib_main;
+
+  hdlc_protocol_info_t * protocol_infos;
+
+  /* Hash tables mapping name/protocol to protocol info index. */
+  uword * protocol_info_by_name, * protocol_info_by_protocol;
+} hdlc_main_t;
+
+always_inline hdlc_protocol_info_t *
+hdlc_get_protocol_info (hdlc_main_t * em, hdlc_protocol_t protocol)
+{
+  uword * p = hash_get (em->protocol_info_by_protocol, protocol);
+  return p ? vec_elt_at_index (em->protocol_infos, p[0]) : 0;
+}
+
+extern hdlc_main_t hdlc_main;
+
+/* Register given node index to take input for given hdlc type. */
+void
+hdlc_register_input_type (vlib_main_t * vm,
+			 hdlc_protocol_t protocol,
+			 u32 node_index);
+
+void hdlc_set_adjacency (vnet_rewrite_header_t * rw,
+			uword max_data_bytes,
+			hdlc_protocol_t protocol);
+
+format_function_t format_hdlc_protocol;
+format_function_t format_hdlc_header;
+format_function_t format_hdlc_header_with_length;
+
+/* Parse hdlc protocol as 0xXXXX or protocol name.
+   In either host or network byte order. */
+unformat_function_t unformat_hdlc_protocol_host_byte_order;
+unformat_function_t unformat_hdlc_protocol_net_byte_order;
+
+/* Parse hdlc header. */
+unformat_function_t unformat_hdlc_header;
+unformat_function_t unformat_pg_hdlc_header;
+
+always_inline void
+hdlc_setup_node (vlib_main_t * vm, u32 node_index)
+{
+  vlib_node_t * n = vlib_get_node (vm, node_index);
+  pg_node_t * pn = pg_get_node (node_index);
+
+  n->format_buffer = format_hdlc_header_with_length;
+  n->unformat_buffer = unformat_hdlc_header;
+  pn->unformat_edit = unformat_pg_hdlc_header;
+}
+
+void
+hdlc_register_input_protocol (vlib_main_t * vm,
+			     hdlc_protocol_t protocol,
+			     u32 node_index);
+
+#endif /* included_hdlc_h */
diff --git a/src/vnet/hdlc/node.c b/src/vnet/hdlc/node.c
new file mode 100644
index 00000000000..4fe0296aca1
--- /dev/null
+++ b/src/vnet/hdlc/node.c
@@ -0,0 +1,351 @@
+/*
+ * 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.
+ */
+/*
+ * hdlc_node.c: hdlc packet processing
+ *
+ * Copyright (c) 2010 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <vlib/vlib.h>
+#include <vnet/pg/pg.h>
+#include <vnet/hdlc/hdlc.h>
+#include <vppinfra/sparse_vec.h>
+
+#define foreach_hdlc_input_next			\
+  _ (PUNT, "error-punt")			\
+  _ (DROP, "error-drop")
+
+typedef enum {
+#define _(s,n) HDLC_INPUT_NEXT_##s,
+  foreach_hdlc_input_next
+#undef _
+  HDLC_INPUT_N_NEXT,
+} hdlc_input_next_t;
+
+typedef struct {
+  u8 packet_data[32];
+} hdlc_input_trace_t;
+
+static u8 * format_hdlc_input_trace (u8 * s, va_list * va)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
+  hdlc_input_trace_t * t = va_arg (*va, hdlc_input_trace_t *);
+
+  s = format (s, "%U", format_hdlc_header, t->packet_data);
+
+  return s;
+}
+
+typedef struct {
+  /* Sparse vector mapping hdlc protocol in network byte order
+     to next index. */
+  u16 * next_by_protocol;
+
+  u32 * sparse_index_by_next_index;
+} hdlc_input_runtime_t;
+
+static uword
+hdlc_input (vlib_main_t * vm,
+	   vlib_node_runtime_t * node,
+	   vlib_frame_t * from_frame)
+{
+  hdlc_input_runtime_t * rt = (void *) node->runtime_data;
+  u32 n_left_from, next_index, i_next, * from, * to_next;
+
+  from = vlib_frame_vector_args (from_frame);
+  n_left_from = from_frame->n_vectors;
+
+  if (node->flags & VLIB_NODE_FLAG_TRACE)
+    vlib_trace_frame_buffers_only (vm, node,
+				   from,
+				   n_left_from,
+				   sizeof (from[0]),
+				   sizeof (hdlc_input_trace_t));
+
+  next_index = node->cached_next_index;
+  i_next = vec_elt (rt->sparse_index_by_next_index, next_index);
+
+  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)
+	{
+	  u32 bi0, bi1;
+	  vlib_buffer_t * b0, * b1;
+	  hdlc_header_t * h0, * h1;
+	  u32 i0, i1, len0, len1, protocol0, protocol1, enqueue_code;
+
+	  /* Prefetch next iteration. */
+	  {
+	    vlib_buffer_t * b2, * b3;
+
+	    b2 = vlib_get_buffer (vm, from[2]);
+	    b3 = vlib_get_buffer (vm, from[3]);
+
+	    vlib_prefetch_buffer_header (b2, LOAD);
+	    vlib_prefetch_buffer_header (b3, LOAD);
+
+	    CLIB_PREFETCH (b2->data, sizeof (h0[0]), LOAD);
+	    CLIB_PREFETCH (b3->data, sizeof (h1[0]), LOAD);
+	  }
+
+	  bi0 = from[0];
+	  bi1 = from[1];
+	  to_next[0] = bi0;
+	  to_next[1] = bi1;
+	  from += 2;
+	  to_next += 2;
+	  n_left_to_next -= 2;
+	  n_left_from -= 2;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+
+	  h0 = (void *) (b0->data + b0->current_data);
+	  h1 = (void *) (b1->data + b1->current_data);
+
+	  protocol0 = h0->protocol;
+	  protocol1 = h1->protocol;
+
+	  /* Add padding bytes for OSI protocols. */
+	  len0 = sizeof (h0[0]);
+	  len1 = sizeof (h1[0]);
+	  
+	  len0 += protocol0 == clib_host_to_net_u16 (HDLC_PROTOCOL_osi);
+	  len1 += protocol1 == clib_host_to_net_u16 (HDLC_PROTOCOL_osi);
+
+	  b0->current_data += len0;
+	  b1->current_data += len1;
+
+	  b0->current_length -= len0;
+	  b1->current_length -= len1;
+
+	  /* Index sparse array with network byte order. */
+	  sparse_vec_index2 (rt->next_by_protocol, protocol0, protocol1, &i0, &i1);
+
+	  b0->error = node->errors[i0 == SPARSE_VEC_INVALID_INDEX ? HDLC_ERROR_UNKNOWN_PROTOCOL : HDLC_ERROR_NONE];
+	  b1->error = node->errors[i1 == SPARSE_VEC_INVALID_INDEX ? HDLC_ERROR_UNKNOWN_PROTOCOL : HDLC_ERROR_NONE];
+
+	  enqueue_code = (i0 != i_next) + 2*(i1 != i_next);
+
+	  if (PREDICT_FALSE (enqueue_code != 0))
+	    {
+	      switch (enqueue_code)
+		{
+		case 1:
+		  /* A B A */
+		  to_next[-2] = bi1;
+		  to_next -= 1;
+		  n_left_to_next += 1;
+		  vlib_set_next_frame_buffer (vm, node, vec_elt (rt->next_by_protocol, i0), bi0);
+		  break;
+
+		case 2:
+		  /* A A B */
+		  to_next -= 1;
+		  n_left_to_next += 1;
+		  vlib_set_next_frame_buffer (vm, node, vec_elt (rt->next_by_protocol, i1), bi1);
+		  break;
+
+		case 3:
+		  /* A B B or A B C */
+		  to_next -= 2;
+		  n_left_to_next += 2;
+		  vlib_set_next_frame_buffer (vm, node, vec_elt (rt->next_by_protocol, i0), bi0);
+		  vlib_set_next_frame_buffer (vm, node, vec_elt (rt->next_by_protocol, i1), bi1);
+		  if (i0 == i1)
+		    {
+		      vlib_put_next_frame (vm, node, next_index,
+					   n_left_to_next);
+		      i_next = i1;
+		      next_index = vec_elt (rt->next_by_protocol, i_next);
+		      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+		    }
+		}
+	    }
+	}
+    
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 bi0;
+	  vlib_buffer_t * b0;
+	  hdlc_header_t * h0;
+	  u32 i0, len0, protocol0;
+
+	  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 = (void *) (b0->data + b0->current_data);
+
+	  protocol0 = h0->protocol;
+
+	  /* Add padding bytes for OSI protocols. */
+	  len0 = sizeof (h0[0]);
+	  len0 += protocol0 == clib_host_to_net_u16 (HDLC_PROTOCOL_osi);
+
+	  b0->current_data += len0;
+	  b0->current_length -= len0;
+
+	  i0 = sparse_vec_index (rt->next_by_protocol, protocol0);
+
+	  b0->error = node->errors[i0 == SPARSE_VEC_INVALID_INDEX ? HDLC_ERROR_UNKNOWN_PROTOCOL : HDLC_ERROR_NONE];
+	  
+	  /* Sent packet to wrong next? */
+	  if (PREDICT_FALSE (i0 != i_next))
+	    {
+	      /* Return old frame; remove incorrectly enqueued packet. */
+	      vlib_put_next_frame (vm, node, next_index, n_left_to_next + 1);
+
+	      /* Send to correct next. */
+	      i_next = i0;
+	      next_index = vec_elt (rt->next_by_protocol, i_next);
+	      vlib_get_next_frame (vm, node, next_index,
+				   to_next, n_left_to_next);
+
+	      to_next[0] = bi0;
+	      to_next += 1;
+	      n_left_to_next -= 1;
+	    }
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return from_frame->n_vectors;
+}
+
+static char * hdlc_error_strings[] = {
+#define hdlc_error(n,s) s,
+#include "error.def"
+#undef hdlc_error
+};
+
+VLIB_REGISTER_NODE (hdlc_input_node) = {
+  .function = hdlc_input,
+  .name = "hdlc-input",
+  /* Takes a vector of packets. */
+  .vector_size = sizeof (u32),
+
+  .runtime_data_bytes = sizeof (hdlc_input_runtime_t),
+
+  .n_errors = HDLC_N_ERROR,
+  .error_strings = hdlc_error_strings,
+
+  .n_next_nodes = HDLC_INPUT_N_NEXT,
+  .next_nodes = {
+#define _(s,n) [HDLC_INPUT_NEXT_##s] = n,
+    foreach_hdlc_input_next
+#undef _
+  },
+
+  .format_buffer = format_hdlc_header_with_length,
+  .format_trace = format_hdlc_input_trace,
+  .unformat_buffer = unformat_hdlc_header,
+};
+
+static clib_error_t * hdlc_input_init (vlib_main_t * vm)
+{
+  hdlc_input_runtime_t * rt;
+
+  {
+    clib_error_t * error = vlib_call_init_function (vm, hdlc_init);
+    if (error)
+      clib_error_report (error);
+  }
+
+  hdlc_setup_node (vm, hdlc_input_node.index);
+
+  rt = vlib_node_get_runtime_data (vm, hdlc_input_node.index);
+
+  rt->next_by_protocol = sparse_vec_new
+    (/* elt bytes */ sizeof (rt->next_by_protocol[0]),
+     /* bits in index */ BITS (((hdlc_header_t *) 0)->protocol));
+
+  vec_validate (rt->sparse_index_by_next_index, HDLC_INPUT_NEXT_DROP);
+  vec_validate (rt->sparse_index_by_next_index, HDLC_INPUT_NEXT_PUNT);
+  rt->sparse_index_by_next_index[HDLC_INPUT_NEXT_DROP]
+    = SPARSE_VEC_INVALID_INDEX;
+  rt->sparse_index_by_next_index[HDLC_INPUT_NEXT_PUNT]
+    = SPARSE_VEC_INVALID_INDEX;
+
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (hdlc_input_init);
+
+void
+hdlc_register_input_protocol (vlib_main_t * vm,
+			     hdlc_protocol_t protocol,
+			     u32 node_index)
+{
+  hdlc_main_t * em = &hdlc_main;
+  hdlc_protocol_info_t * pi;
+  hdlc_input_runtime_t * rt;
+  u16 * n;
+  u32 i;
+
+  {
+    clib_error_t * error = vlib_call_init_function (vm, hdlc_input_init);
+    if (error)
+      clib_error_report (error);
+  }
+
+  pi = hdlc_get_protocol_info (em, protocol);
+  pi->node_index = node_index;
+  pi->next_index = vlib_node_add_next (vm, 
+				       hdlc_input_node.index,
+				       node_index);
+
+  /* Setup hdlc protocol -> next index sparse vector mapping. */
+  rt = vlib_node_get_runtime_data (vm, hdlc_input_node.index);
+  n = sparse_vec_validate (rt->next_by_protocol, clib_host_to_net_u16 (protocol));
+  n[0] = pi->next_index;
+
+  /* Rebuild next index -> sparse index inverse mapping when sparse vector
+     is updated. */
+  vec_validate (rt->sparse_index_by_next_index, pi->next_index);
+  for (i = 1; i < vec_len (rt->next_by_protocol); i++)
+    rt->sparse_index_by_next_index[rt->next_by_protocol[i]] = i;
+}
diff --git a/src/vnet/hdlc/packet.h b/src/vnet/hdlc/packet.h
new file mode 100644
index 00000000000..45e5496fbc8
--- /dev/null
+++ b/src/vnet/hdlc/packet.h
@@ -0,0 +1,72 @@
+/*
+ * 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.
+ */
+#ifndef included_vnet_hdlc_packet_h
+#define included_vnet_hdlc_packet_h
+
+/*
+ * HDLC packet format
+ *
+ * Copyright (c) 2009 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#define foreach_hdlc_protocol			\
+  _ (0x0800, ip4)				\
+  _ (0x2000, cdp)				\
+  _ (0x8035, slarp)				\
+  _ (0x8847, mpls_unicast)			\
+  _ (0x8848, mpls_multicast)			\
+  _ (0x86dd, ip6)				\
+  _ (0xfefe, osi)
+
+typedef enum {
+#define _(n,f) HDLC_PROTOCOL_##f = n,
+  foreach_hdlc_protocol
+#undef _
+} hdlc_protocol_t;
+
+typedef struct {
+  /* Set to 0x0f for unicast; 0x8f for broadcast. */
+  u8 address;
+
+  /* Always zero. */
+  u8 control;
+
+  /* Layer 3 protocol for this packet. */
+  u16 protocol;
+
+  /* Layer 3 payload. */
+  u8 payload[0];
+} hdlc_header_t;
+
+#endif /* included_vnet_hdlc_packet_h */
diff --git a/src/vnet/hdlc/pg.c b/src/vnet/hdlc/pg.c
new file mode 100644
index 00000000000..b8e67022b08
--- /dev/null
+++ b/src/vnet/hdlc/pg.c
@@ -0,0 +1,105 @@
+/*
+ * 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.
+ */
+/*
+ * hdlc_pg.c: packet generator hdlc interface
+ *
+ * Copyright (c) 2008 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <vlib/vlib.h>
+#include <vnet/pg/pg.h>
+#include <vnet/hdlc/hdlc.h>
+
+typedef struct {
+  pg_edit_t address;
+  pg_edit_t control;
+  pg_edit_t protocol;
+} pg_hdlc_header_t;
+
+static inline void
+pg_hdlc_header_init (pg_hdlc_header_t * e)
+{
+  pg_edit_init (&e->address, hdlc_header_t, address);
+  pg_edit_init (&e->control, hdlc_header_t, control);
+  pg_edit_init (&e->protocol, hdlc_header_t, protocol);
+}
+
+uword
+unformat_pg_hdlc_header (unformat_input_t * input, va_list * args)
+{
+  pg_stream_t * s = va_arg (*args, pg_stream_t *);
+  pg_hdlc_header_t * h;
+  u32 group_index, error;
+  
+  h = pg_create_edit_group (s, sizeof (h[0]), sizeof (hdlc_header_t),
+			    &group_index);
+  pg_hdlc_header_init (h);
+
+  pg_edit_set_fixed (&h->address, 0x0f);
+  pg_edit_set_fixed (&h->control, 0x00);
+
+  error = 1;
+  if (! unformat (input, "%U",
+		  unformat_pg_edit,
+		    unformat_hdlc_protocol_net_byte_order, &h->protocol))
+    goto done;
+
+  {
+    hdlc_main_t * pm = &hdlc_main;
+    hdlc_protocol_info_t * pi = 0;
+    pg_node_t * pg_node = 0;
+
+    if (h->protocol.type == PG_EDIT_FIXED)
+      {
+	u16 t = *(u16 *) h->protocol.values[PG_EDIT_LO];
+	pi = hdlc_get_protocol_info (pm, clib_net_to_host_u16 (t));
+	if (pi && pi->node_index != ~0)
+	  pg_node = pg_get_node (pi->node_index);
+      }
+
+    if (pg_node && pg_node->unformat_edit
+	&& unformat_user (input, pg_node->unformat_edit, s))
+      ;
+
+    else if (! unformat_user (input, unformat_pg_payload, s))
+      goto done;
+  }
+
+  error = 0;
+ done:
+  if (error)
+    pg_free_edit_group (s);
+  return error == 0;
+}
+